[Document Type] Specification
[Title of the Inventio~l] METHOD FOR MANUFACTURING PRESS-FORMED
PRODUCT, DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT,
MANDREL, AND PRESS-FORMED PRODUCT
[Technical Field of the Invention]
[0001]
The present invention relates to a method for manufacturing a press-formed
product, a device for manufacturing a press-formed product, a mandrel, and a
press-formed product.
Priority is claimed on Japanese Patent Application No. 2014-042144, filed on
March 4,2014, Japanese Patent Application No. 2014-057177, filed on March 19,2014,
and Japanese Patent Application No. 2014-209361, filed on October 10,2014, the
contents of which are incorporated herein by reference.
[Related Art]
[0002]
In automobiles, high rigidity of a vehicle body is required in order to secure
handling stability or the like while a decrease in weight of the vehicle body is required
to improve fuel consumption. Apress-formed product obtained by press-forming a
steel sheet is used in a portion of a skeleton member of the vehicle body. Decreasing
the thickness of the press-formed product is considered to decrease the weight of the
vehicle body. However, if the thickness decreases, rigidity decreases. Accordingly,
in order to decrease the weight of the press-formed product and increase the rigidity
thereof, increasing the thickness of a portion of the press-formed product is considered.
[0003]
For example, Patent Document 1 discloses a method for manufacturing a
vehicle component using a tailored blank material. In addition, a steel sheet
(reinforcing material) may be welded to the skeleton member of the vehicle body so as
to partially increase the thickness of the skeleton member,
[Citation List]
[Patent Document]
[0004]
[Patent Document 11 Japanese Unexanined Patent Application, First
Publication No. 2005-152975
[Disclosure of the Invention]
[Problen~sto be Solved by the In~rention]
[0005]
A tailored blank material is mauufactured by welding steel sheets having
tensile strength different from each other or stecl sheets having thicknesses different
from each other. However, in a case where the tailored blank material is press-formed,
stress is concentrated in a weld, and there is a concern that cracks or ruptures occur. In
addition, since a welding process is required, there is a concern that production
efficiency decreases.
[0006]
In addition, in a case where a steel sheet is welded to a skeleton member of a
vehicle body so as to partially increase the thickness, weight ofthe skeleton member
increases, and this case goes against a decrease in the weight of the vehicle. In
addition, in this case, similarly to the case of the tailored blank material, since a welding
process is required, there is a concern that production efficiency decreases.
[0007]
The present invention is made in consideration of the above-described
circumferences, and an object thereof is to provide a method for manufacturing a
press-formed product, a device for manufacturing a press-formed product, a mandrel,
and a press-formed product capable of simultaneously achieving a decrease in weight
and high rigidity without the need of welding.
[Means for Solving the Problem]
[OOOS]
In order to solve the problems, the present invention adopts the following.
(1) According to a first aspect of the present invention, a method for
manufacturing a press-formed product, includes: a first step of preparing a long material
having a bending portion; and a second step of decreasing curvature of the bending
portion while restricting both ends of the long material in a longitudinal direction.
(2) In the aspect according to (I), in the second step, the curvature may
decrease while the shortest distance between both ends of the long material is constantly
maintained.
(3) In the aspect according to (I), in the second step, the curvature may
decrease while the shortest distance between both ends ofthe long material decreases.
(4) In the aspect accordiug to any one of (I) to (3), in the second step, the
curvature may decrease while at least a concave side of the bending portion of the long
material is supported.
(5) In the aspect according to any one of (1) to (4), in the second step, the
curvature may decrease in stages.
(6) In the aspect according to any one of (I) to (5), planes including edges of
both ends of the long material may be parallel with each other.
[0009]
(7) According to a second aspect of thc present invention, a device for
manufacturing a press-formed product using a long material having a bending portion,
includes: a first press tool which includes a base portion, and a pair of restriction walls
which is provided on the base portion, comes into contact with both ends of the long
material in a longitudinal direction, and faces each other; and a second press tool which
includes a punch portion which presses a convex side of the bending portion of the long
material inserted into between the pair of restriction walls, in which the distance
between the pair of restriction walls is shorter than the entire length when the long
material linearly extends.
(8) In the aspect according to (7), the distance between the pair of restriction
walls may be the same as the shortest distance between both ends of the long material in
the longitudinal direction.
(9) In the aspect according to (7) or (8), each of the pair of restriction walls
may include a curve shaped guide surface which comes into contact with the end
portion of the long material in the longitudinal direction when the long material is
inserted between the restriction walls.
(10) In the aspect according to any one of (7) to (9), the device for
manufacturing a press-formed product may further include a blank bolder tool which is
disposed between the pair of restriction walls, and includes a support surface which
comes into contact with at least a concave side of the bending portion of the long
material.
(11) In the aspect according to (7), one of the pair of restriction walls may be
a fixing restriction wall which is fixed to the base portion, and the other of the pair of
restriction walls may be a pressurization restriction wall which approaches the fixing
restriction wall when the punch poi-tion moves while coming into contact with the
convex side of the bending portion of the long material.
(12) In the aspect according to (ll), at least one of the fixing restriction wall
and the pressurization restriction wall may include a workpiece receiving portion which
comes into contact with one end of the long material, and an elastic body which biascs
the workpiece receiving portion toward the one end of the long material.
(13) In the aspect according to (11) 01 (12), the device for manufacturing a
press-formed product may furthet include a blank holder tool which is disposed
between the fixing restriction wall and the pressurization restriction wall, and includes a
support surface which comes into contact with at least a concave side of the bending
portion of the long material.
[OOl 01
(14) According to a third aspect of the present invention, a mandrel which is
used in the device for manufacturing a press-formed product according to any one of (7)
to (13), includes: a plurality of division bodies which support the concave side of thc
long material; and a connection body which connects the division bodies, in which a
line shape of the division bodies is changed according to the shape of the bending
portion of the long material.
(1 5) In the aspect according to (14), each division body may include a
concave portion which accommodates the connection body when the division bodies are
arranged in a line, and an elastic body which is provided between a bottom surface of
the concave portion and an end portion of the connection body inserted into the concave
portion.
(16) In the aspect according to (14), the connection body may include a pair
of division connection bodies which is movable close to and away from each other
within a predetermined range, and an elastic body which is provided between the pair of
division connection bodies and biases the pair of division connection bodies in a
direction separated from each other.
[OOll]
(17) According to a fourth aspect of the present invention, a press-formed
product which is long in one direction, includes: a high cross-sectional area portion
which has the largest cross-sectional area when viewed in a cross section perpendicular
to a longitudinal direction; a low cross-sectional area portion which has a
cross-sectional area which is smaller than that of the high cross-sectional area portion;
and an intermediate portion which is provided between the high cross-sectional area
portion and the low cross-sectional ales portion, and in which a cross-sectional area
continuously changes along the longitudinal direction.
(1 8) In the aspect according to (17), a plurality of high cross-sectional area
portions may be provided in a plurality of locations along the longitudinal direction.
[Effects of the Invention]
[OO12]
According to the method for manufacturing a press-formed product described
in (I), since the curvature of the bending portion decreases while both ends of the long
material having the bending portion in the longitudinal direction are restricted, it is
possible to compress the long material in the longitudinal direction. That is, since the
compressed portion becomes a surplus, it is possible to increase a cross-sectional area of
the long material. Accordingly, it is possible to increase the rigidity of the long
material
Moreover, since the long material is compressed in the longitudinal direction, it
is possible to increase yield strength of the long material due to work hardening of the
long material.
In addition, since the cross-sectional area at the location corresponding to the
bending portion increases, by arbitrarily selecting the position of the bending portion of
the long material, it is possible to increase the cross-sectional area at a desired location.
[0013]
In the case of (2), since the curvature of the bending portion of the long
material decreases while the shortest distance between both ends of the long material is
constantly maintained, it is possible to further compress the long material in the
longitudinal direction. That is, since the surplus of the long material increases, it is
possible to further increase the cross-sectional area of the long material.
[0014]
In the case of (3), since the curvature of the bending portion of the long
material decreases while the shortest distance between both ends of the long material
decreases, it is possible to further compress the long material in the longitudinal
direction. That is, since the surplus of the long material increases, it is possible to
further increase the cross-sectional area of the long material.
[OOlS]
Moreover, in the case of (4), since the curvature of the bending portion of the
long material decreases while the concave side of the long material is supported, it is
possible to prevent buckling distortion of the long material.
[0016]
In the case of (S), since the curvature of the bending portion of the long
material decreases in stages, it is possible to gradually increase the cross-sectional area
of the long material. That is, since it is difficult to buckle the long material by the
increase in the cross-sectional area, it is possible to prevent the buckling distortion of
the long material when the curvature of the bending portion decreases to a
predetermined curvature.
[00 171
In the case of (6), since planes including edges of both ends of the long
material are parallel with each other, it is possible to equally apply a load to both ends
of the long material. Accordingly, it is possible to prevent the buckling distortion of
the long material.
[OO 1 81
According to the device for manufacturing a press-formed product described in
(7), since the device includes the second press tool which includes the punch portiol~
which presses the convex side of the bending portion of the long material inserted
between the pair of restriction walls, it is possible to decrease the curvature of the
bending portion of the long material. In addition, since the distance between the pair
of restriction walls is shorter than the entire length when the long material linearly
extends, it is possible to restrict the long material in the longitudinal direction when the
long material is pressed by the punch portion. Accordingly, it is possible to conlpress
the long material in the longitudinal direction. That is, since the compressed portion
becomes a surplus, it is possible to increase the cross-sectional area of the long material.
[00 191
In the case of (8), since the distance between the pair of restriction walls is the
same as the shortest distance between both ends of the long material in the longitudinal
direction, it is possible to further compress the long material in the longitudinal
direction. That is, since the surplus of the long material increases, it is possible to
further increase the cross-sectional area of the long material.
[0020]
In the case of (9), since each of the pair of restriction walls includes the guide
surface which comes into contact with the end portion of the long material in the
longitudinal direction when the long material is inserted between the restriction walls,
the long material is introduced into the portion between the pair of restriction walls.
Accordingly, since it is possible to reliably restrict the long material, it is possible to
prevent buckling distortion.
[0021]
In the case of (1 O), since the device for manufacturing a press-formed product
includes the blank holder tool which is disposed between the pair of restriction walls,
and includes the support surface which comes into contact with at least the concave side
of the bending portion of the long material, it is possible to prevent the buckling
distortion when the long material is compressed in the longitudinal direction.
200221
In the case of (1 I), since one of the pair of restriction walls is the fixing
restriction wall, and the other is the pressurization restriction wall which approaches the
fixing restriction wall when the punch portion moves while coming into contact with the
convex side of the bending portion ofthe long material, it is possible to further
compress the long material in the longitudinal dircction. Accordingly, it is possible to
further increase the cross-sectional area of the long material.
[0023]
In the case of (12), since at least one of thc fixing restriction wall and the
pressurization restriction wall includes the workpiece receiving portion which comes
into contact with one end of the long material, and the elastic body which biases the
workpiece receiving portion toward the one end of the long material, it is possible to
follow the distortion of both ends of the long material when the long material is
compressed in the longitudinal direction. That is, when the punch portion presses the
convex side of the bending portion of the long material, it is possible to restrict the
entire portion of both ends of the long material. Therefore, since it is possible to
equally apply a compressive force to the long material, it is possible to prevent the
buckling distortion when the long material is compressed.
[0024]
In the case of (13), since the device for manufacturing a press-formed product
further includes the blank holder tool which is disposed between the fixing restriction
wall and the pressurization restriction wall, and includes the support surface which
comes into contact with at least the concave side of the bending portion of the long
material, it is possible to prevent the buckling distortion when the long material is
compressed in the longitudinal direction.
[0025]
According to the mandrel described in (14), since the line shape of the division
bodies is changed according to the shape of the bending portion of the long material, the
plurality of division bodies which support the concave side of the long material can
follow the distortion of the long material. Accordingly, when the long material is
compressed in the longitudinal direction, it is possible to always support the long
material, and it is possible to prevent the buckling distortion when the long material is
compressed in the longitudinal direction.
[0026]
In the case of (1 5), since each division body includes the concave portion
which accommodates the connection body when the division bodies are arranged in a
line, and the elastic body which is provided between the bottom surface of the concave
portion and the end portion of the connection body inserted into the concave poi-tion, it
is possible to increase and decrease the entire length of the mandrel. Accordingly, it is
possible to allow the division bodies to come into contact with the approximately
entirety ofthe long material. Therefore, it is possible to prevent the buckling
distortion when the long material is compressed in the longitudinal direction.
loo271
In the case of (16), since each connection body includes the pair of division
connection bodies which is movable close to and away from each other, and the elastic
body which is provided between the pair of division connection bodies and biases the
pair of division connection bodies in a direction separated from each other, it is possible
to increase and decrease the entire length of the mandrel. Accordingly, it is possible to
allow the division bodies to come into contact with the approximately entirety of the
long material. Therefore, it is possible to prevent the buckling distortion when the
long material is compressed in the longitudinal direction.
[0028]
According to the press-formed product described in (17), since the
press-formed product includes the high cross-sectional area portion, it is possible to
increase rigidity of the press-formed product. Moreover, since the press-formed
product includes the low cross-sectional area portion, it is possible to decrease weight of
the press-formed product.
In addition, since the press-formed product includes the intermediate portion in
which the cross-sectional area continuously changes along the longitudinal direction, it
is possible to prevent stress from being concentrated in a boundary between the high
cross-sectional area portion and the low cross-sectional area portion.
[0029]
In the case of (IS), since the plurality of high cross-sectional area portions are
provided, it is possible to further increase the rigidity of the press-formed product.
[Brief Description of the Drawings]
[0030]
FIG. 1A is a perspective view showing an intermediate press-formed product
which is used in a device for manufacturing a press-formed product according to a first
embodiment of the present invention
FIG. 1B is a front view showing the inteimediate press-formed product.
FIG. 1C is a plan view showing the intermediate press-formed product.
FIG. 1D is a side view showing the intermediate press-formed product.
FIG. 2 is a perspective view showing the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 3A is a front view showing the device for manufacturing a press-forn~ed
product according to the first e~ubodimenot f the present invention.
FIG. 3B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 4A is a front view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a bottom dead centcr.
FIG. 4B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 5A is a perspective view showing a press-formed product according to the
first embodiment of the present invention.
FIG. 5B is a front view showing the press-formed product.
FIG. 5C is a side view showing the press-formed product.
FIG. 6A is a sectional view taken along line A-A of FIG. 5C.
FIG. 6B is a sectional view taken along line A-A of FIG. 5C.
FIG. 6C is a sectional view taken along line A-A of FIG. 5C.
FIG. 6D is a bottom view showing the press-formed product.
FIG. 6E is a bottom view showing the press-formed product.
FIG. 6F is a bottom view showing the press-formed product.
FIG. 7A is a perspective view showing a modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 7B is a front view showing the intermediate press-formed product.
FIG. 7C is a side view showing the intermediate press-formed product.
FIG. 8 is a front view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 9A is a view showing a modification example of the press-formed product
according to the first embodiment of the present invention.
FIG. 9B is a side view showing the modification example of the press-formed
product according to the first embodiment of the present invention.
FIG. 9C is a sectional view taken along line B-B of FIG. 9B.
FIG. 9D is a sectional view takcn along line B-B of FIG. 9B.
FIG. 9E is a sectional view taken along line B-B of FIG. 9B.
FIG. 9F is a bottom view showing the modification example of the
press-formed product according to the first embodiment ofthe present invention.
FIG. 9G is a bottom view showing the modification example of the
press-formed product according to the fxst embodiment of the prcsent invention.
FIG. 9H is a bottom view showing the modification example of the
press-formed product according to the first embodiment of the prcsent invention.
FIG. 10A is a perspective view showing another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 10B is a view showing the intermediate press-formed product, and is a
perspective view when viewed from a direction different from that of FIG. 1OA.
FIG. 10C is a front view showing the intermediate press-formed product.
FIG. llAis a front view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 11B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 12A is a front view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 12B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention, and is a view
showing the state where the upper press tool is lowered to the bottom dead center.
FIG. 13A is a front view showing still another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 13B is a plan view showing the intermediate press-formed product.
FIG. 13C is a perspective view showing the intermediate press-formed product.
FIG. 14 is a fiont view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 15A is a front view showing still another modification example of the
press-formed product according to the first embodiment of the present invention.
FIG. 15B is a side view showing still another modification example of the
press-formed product according to the first embodiment of the present invention.
FIG. 15C is a sectional view taken along line C-C of FIG 15B.
FIG. 15D is a sectional view taken along line C-C of FIG. 15B.
FIG. 15E is a sectional view takcn along line C-C of FIG. 15B.
FIG. 15F is a bottom view sl~owingst ill another modification example of the
press-foimed product according to thc first embodiment of the present invention.
FIG. 15G is a bottom view showing still another modification example of the
press-formed product according to the first embodiment of the present invention.
FIG. 15H is a bottom view showing still another modification example of the
press-formed product according to the first embodiment of the present invention.
FIG. 16A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first e~nbodimento f the present invention.
FIG. 16B is a side view showing the device for manufacturing a press-formed
product according to the first embodi~nenot f the present invention.
FIG. 17A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 17B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 18A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG 18B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 19A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 19B is a side view showing the device for manufacturing a press-fo~med
product according to the first embodiment of the present invention.
FIG. 20Ais a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 20B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 21A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodiment of the present invention.
FIG. 21 B is a side view showing the device for manufacturing a press-formed
product according lo the first embodi~nenot f the present invention.
FIG. 22A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-fo~medp roduct according to the first embodiment of the present invention.
FIG. 22B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 23A is a perspective view showing still another ~uodificatione xample of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the first embodime~lot f the present invention.
FIG. 23B is a side view showing the device for manufacturing a press-formed
product according to the first embodiment of the present invention.
FIG. 24A is a perspective view showing an intermediate press-formed product
which is used in a device for manufacturing a press-formed product according to a
second embodiment of the present invention.
FIG. 24B is a front view showing the intermediate press-formed product.
FIG. 25A is a perspective view showing the device for manufacturing a
press-formed product according to the second embodiment of the present invention.
FIG. 25B is a side view showing the device for manufactwing a press-formed
product according to the second embodiment of the present invention.
FIG. 26 is a front view showing the device for manufacturing a press-formed
product according to the second embodiment of the present invention.
FIG. 27A is a front view showing the device for manufacturing a press-formed
product according to the second embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a bottom dead center.
FIG. 27B is a side view showing the device for manufacturing a press-formed
product according to the second embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 28A is a perspective view showing a modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the second embodiment of the present invention.
FIG. 28B is a front view showing the intermediate press-formed product.
FIG. 28C is a side view showing the intermediate press-formed product.
FIG. 28D is a plan view showing the intermediate press-formed product.
FIG. 29 is a front view showing the device for manufacturing a press-formed
product according to the second embodiment of the present invention.
FIG. 30A is a front view showing a device for manufacturing a press-formed
product according to a third embodiment of the present invention.
FIG. 30B is a side view showing the device for manufacturing a prcss-fo~med
product according to the third embodiment of the present invention.
FIG. 3 1A is a front view showing the device for manufacturing a press-formed
product according to the third embodiment of the present invention, aid is a view
showing a state where an upper press tool is lowered to a bottom dead center.
FIG. 3 1B is a side view showing the device for manufacturing a press-formed
product according to the third embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 32A is a front vicw showing a blank holder pad.
FIG. 32B is a side view showing the blank holder pad.
FIG. 32C is a plan view showing the blank holder pad.
FIG. 33A is a perspective view showing a modification example of the
intermediate press-fonned product which is used in the device for manufacturi~lga
press-formed product according to the third embodiment of the present invention.
FIG. 33B is a front view showing the intermediate press-formed product.
FIG. 33C is a plan view showing the intermediate press-formed product.
FIG. 34A is a front view showing the device for manufacturing a press-formed
product according to the third embodiment of the present invention.
FIG. 34B is a front view showing the device for manufacturing a press-formed
product according to the third embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 35A is a perspective view showing another inodification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the third embodiment of the present invention.
FIG 35B is a front view showing the intermediate press-formed product.
FIG. 35C is a plan view showing the intermediate press-formed product.
FIG. 36 is a front view showing the device for manufacturing a press-formed
product according to the thhd embodiment of the present invention.
FIG. 37A is a front view showing a device for manufacturing a press-formed
product according to a fourth embodiment of the present invention.
FIG. 37B is a side view showing the device for manufacturing a press-formed
product according to the fourth embodinlent of the present invention.
FIG. 38 is a front view showing the device for manufacturing a press-formed
product according to the fourth embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a botton~d ead center.
FIG. 39A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the fourth embodiment of the prcsent invention.
FIG. 39B is a front view showing the intermediate press-formed product.
FIG. 39C is a plan view showing the intermediate press-foimed product.
FIG. 40A is a front view showing the device for manufacturing a press-formed
product according to the fourth embodiment of the present invention.
FIG. 40B is a side view showing the device for manufacturing a press-formed
product according to the fourth embodiment of the present invention.
FIG. 41 is a front view showing the device for manufacturing a press-folmed
product according to the fourth embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottoin dead center.
FIG. 42A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the fourth embodiment of the present invention.
FIG. 42B is a front view showing the intermediate press-formed product.
FIG. 42C is a plan view showing the intermediate press-formed product.
FIG. 43 is a front view showing a device for manufacturing a press-formed
product according to a fifth embodiment of the present invention.
FIG. 44 is a view showing a mandrel and an intermediate press-formed product
according to the fifth embodiment of the present invention.
FIG. 45 is a front schematic view showing the mandrel according to the fifth
embodiment of the present invention.
FIG. 46 is an enlarged front view showing the mandrel according to the fifth
embodiment of the present invention.
FIG. 47 is a perspective view showing a connection body of the mandrel
according to the fifth embodiment of the present invention.
FIG. 48 is a perspective view showing a modification example of the
connection body.
FIG. 49 is a front view showing the device for manufacturing a press-formed
product according to the fifth embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a bottom dead center.
FIG. 50 is a front view showing a device for manufacturing a press-formed
product according to a sixth embodiment of the present invention.
FIG. 5 1 is an enlarged front view showing a mandrel according to the sixth
embodiment of the present invention.
FIG. 52 is an enlarged front view showing a modification example of the
mandrel according to the sixth embodi~nenot f the present invention.
FIG. 53 is an enlarged front view showing another modification example of the
mandrel according to the sixth en~bodiinenot f the present invention.
FIG. 54 is a view for explaining an operation of the mandrel according to the
sixth embodiment of the present invention.
FIG. 55 is a view for explaining the operation of the mandrel according to the
sixth embodiment of the present invention.
FIG. 56 is a view for explaining the operation of the mandrel according to the
sixth embodiment of the present invention.
FIG. 57 is an enlaiged front view showing still another modification example of
the mandrel according to the sixth embodiment of the present invention.
FIG. 58 is a front view showing a connection body of the mandrel shown in FIG.
57.
FIG. 59 is a plan view showing a connection body of the mandrel shown in FIG.
57 which is different from the connection body shown in FIG. 58.
FIG. 60A is a perspective view showing an intermediate press-formed product
which is used in a device for manufacturing a press-formed product according to a
seventh embodiment of the present invention
FIG. 60B is a front view showing the intermediate press-formed product.
FIG. 60C is a plan view showing the intermediate press-formed product.
FIG. 61 is a front view showing the device for manufacturing a press-formed
product according to the seventh embodiment of the present invention.
FIG 62 is a side view showing the device for manufacturing a press-formed
product according to the seventh embodiment of the present invention.
FIG 63 is a side view showing the device for manufacturing a press-formed
product according to the seventh embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a bottom dead center.
FIG. 64A is a perspective view showing a modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the sixth embodiment of the present invention.
FIG. 64B is a front view showing the intermediate press-formed product.
FIG. 64C is a plan view showing the intermediate press-formed product.
FIG. 65 is a front view showing the device for manufacturing a press-formed
product according to the seventh embodiment of the present invention.
FIG. 66A is a perspective view showing another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the sqventh embodiment ofthe present invention.
FIG. 66B is a front view showing the intermediate press-formed product.
FIG. 66C is a plan view showing the intermediate press-formed product.
FIG. 67 is a front view showing the device for manufacturing a press-formed
product according to the seventh embodinlent of the present invention.
FIG. 68A is a perspective view showing still another modification example of
the intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the seventh embodiment of the present invention.
FIG. 68B is a front view showing the intermediate press-formed product.
FIG. 68C is a plan view showing the intermediate press-formed product.
FIG. 69 is a front view showing the device for manufactuling a press-formed
product according to the seventh embodiment of the present invention.
FIG. 70 is a perspective view showing a device for manufacturing a
press-formed product according to an eighth embodiment of the present invention.
FIG. 71A is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention.
FIG. 71B is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention, and is a view
showing a state where an upper press tool is lowered to a bottom dead center.
FIG. 71C is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 72A is a perspective view showing a modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the eighth embodiment of the present invention.
FIG 72B is a front view showing intermediate press-formed product.
FIG. 72C is a plan view showing intermediate press-formed product.
FIG. 73A is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention.
FIG. 73B is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention, and is a view
showing a state where the upper press tool is lowered to the bottom dead center.
FIG. 74A is a perspective view showing another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the eighth embodiment of the present invention.
FIG. 74B is a front view showing the intermediate press-formed product.
FIG. 74C is a plan view showing the intermediate press-formed product.
FIG 75A is a front view showing a modification example of the device for
manufacturing a press-formed product according to the eighth enlbodiment of the
present invention.
FIG. 75B is a view showing a state where the upper press tool is lowered to the
bottom dead center from the state shown in FIG. 75A.
FIG. 76 is a perspective vicw showing still another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the eighth embodiment of the present invention.
FIG. 77 is a front view showing the device for manufacturing a press-formed
product according to the eighth embodiment of the present invention.
FIG. 78 is a perspective view showing still another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the eighth embodiment of the present invention.
FIG. 79 is a perspective view showing still another modification example of the
intermediate press-formed product which is used in the device for manufacturing a
press-formed product according to the eighth embodiment of the present invention.
FIG. 80A is a front view showing a modification example of the device for
manufacturing a press-formed product according to the eighth embodiment of the
present invention.
FIG.80B is a front view showing the modification example of the device for
manufacturing a press-formed product according to the eighth embodiment of the
present invention, and a view showing a state where an upper press tool is lowered to a
bottom dead center.
FIG. 81 is a perspective view showing a device for manufacturing a
press-formed product according to a ninth embodiment of the present invention.
FIG. 82A is a longitudinal sectional view showing the device for manufacturing
a press-formed product according to the ninth embodiment of the present invention.
FIG. 82B is a longitudimal sectional view showing the device for manufacturing
a press-formed product according to the ninth embodiment of the present invention, and
is a view showing a state where an upper press tool is lowered.
FIG. 82C is a longitudinal sectional view showing the device for manufacturing
a press-formed product according to the ninth embodiment of the present invention, and
is a view showing a state where the upper press tool is lowered to a bottom dead center.
FIG. 83A is a view for explaining a method in which multiple times of
compression are applied to an intermediate press-formed product.
FIG. 83B is a view for explaining a method in which multiple times of
compression are applied to the intermediate press-fornled product.
FIG. 83C is a view for explaining a method in which multiple times of
compression are applied to the intermediate press-formed product.
[Embodiments of the Invention]
[0031] '
Hereinafter, embodiments of the present invention will be described in detail
with reference to the drawings. In addition, in the present specification and thc
drawings, the same reference numerals are assigned to the components having
substantially the same function as each other, and descriptions thereof are omitted.
[0032]
(First Embodiment)
FIG. 2 is a perspective view showing a device 1 for manufacturing a
press-formed product (hereinafter, simply referred to as a manufacturing device 1)
according to a first embodiment of the present invention. The manufacturing device 1
presses an intermediate press-formed product 5 1 so as to manufacture a press-formed
product 101 (refer to FIGS. 5A to 5C). Hereinafter, first, the intermediate
press-formed product 5 1 will be described.
[0033]
FIGS. lA to 1D are views showing the intermediate press-foimed product 5 1.
In addition, FIG. 1A is a perspective view, FIG. 1B is a front view, FIG. 1C is a plan
view, and FIG. 1D is a side view. As shown in FIG. lA to ID, the intermediate
press-formed product 51 is a steel (long material) which is long in one direction, and is
configured of a web portion 52, and a pair of vertical wall portions 53 which are
provided on both sides of the web portion 52 in a width direction and face each other.
The web portion 52 includes two linear portions 52a (flat portions) and a bending
portion 52b which is provided between the two linear portions 52a.
[0034]
The bending portion 52b of the web portion 52 is a portion which is provided
on the center portion of the web portion 52b in a longitudinal direction and is curved in
an arc shape. Here, in surfaces of the bending portion 52b, a surface (extension
surface) which is extended by bending is referred to as a convex side (extension side),
and the other surface (a surface (constriction surface) which is constricted by bending)
is referred to as a concave side (constriction side) (refer to FIG. IB). Hereinafter, thcse
are similarly applied to all drawings in the present specification.
[0035]
The pair of vertical wall portions 53 is provided on the convex side of the
bending portion 52b of the web portion 52. In addition, when the intermediate
press-formed product 5 1 is viewed fiom the front, the pair of vertical wall portions 53
extends so as to have a constant width between one end and the other end of the web
portion 52. A curvature of the center portion of the vertical wall portion 53 in the
longitudinal direction is the same as a curvature of the bending portion 52b of the web
portion 52.
[003 61
The intermediate press-formed product 5 1 is manufactured by press-forming a
steel sheet. For example, a rectangular steel sheet in a plan view is press-formed so as
to be straight steel having the web portion 52 and the pair of vertical wall portions 53,
and thereafter, the intermediate press-formed product 51 can be manufactured by
bending the steel. In addition, the intermediate press-formed product 5 1 may be
directly manufactured by press-forming the steel sheet without performing the bending.
[0037]
In addition, preferably, in the intermediate press-formed product 5 1, a
slenderness ratio h represented by the following Expression (1) is 100 or more.
h=Ll l r ... (1)
In Expression (I), L1 is the entire length of the intermediate press-formed
product (refer to FIG. IB), and r is a cross-sectional secondary radius which is
represented by the following Expression (2) using a cross-sectional secondary moment I
and a cross-sectional area A of the intermediate press-formed product 5 1.
r = (11~)".~. . (2)
Since the sle,ndemess ratio h is 100 or more, it is possible to easily perform the
bending when the intermediate press-formed product 51 is manufactured.
[0038]
As shown in FIG. lB, a shortest distance L between both ends (both edges) of
the intermediate press-formed product 5 1 in the longitudinal direction is shorter than the
entire length Ll of the intermediate press-formed product 5 1. Here, the entire length
L1 of the intermediate press-formed product 51 means the entire length of the curved
web portion 52. In addition, the shortest distance L means the shortest distance
between short sides 53a and 53b (both edges of vertical wall portion) of the vertical wall
portion 53.
[0039]
Next, the illanufacturing device 1 according to the present embodiment will be
described. As shown in FIG. 2, the manufacturing device 1 includes a lower press tool
10 (first press tool) and an upper press tool 20 (second press tool). Moreover, the
lower press tool 10 and the upper press tool 20 are installed on a press forming machine
(not shown). The press fornling machine may be a general press forming machine.
However, preferably, the press forming machine is a servo-type press forming machine
in which bottoin dead centers and lowering speeds of the press tools can be arbitrarily
adjusted.
[0040]
The lower press tool 10 includes a base portion 11, a pair of long-side walls 12
which is fixed to the base poi-tion 11 and faces each other, and a pair of short-side walls
13 (a pair of restriction walls) which is fixed to the base poition 11 and faces each other.
The upper press tool 20 includes a main body portion 21 and a punch portion 22 which
has a convex portion 23. Moreover, in the lower press tool 10, a groove portion 14 is
formed by the pair of long-side walls 12 and the pair of short-side walls 13.
[0041]
When the press-formed product 101 is manufactured, the intermediate
press-formed product 51 is disposed between the lower press tool 10 and the upper
press tool 20. In addition, by lowering the upper press tool 20, the intermediate
press-formed product 51 is pressed and pushed into the groove poi-tion 14.
[0042]
FIG. 3A is a longitudinal sectional view showing the manufacturing device 1,
and FIG. 3B is a cross sectional view showing the manufacturing device 1. As shown
in FIGS. 3A and 3B, wall surfaces 13a (side surfaces) of the pair of short-side walls 13
and wall surfaces 12a of the pair of the long-side walls 12 are perpendicular to an upper
surface 1 la of the base portion 11. In addition, a convex surface 13b (guide surface) is
provided on each of upper portions of the wall surfaces 13a.
[0043]
As shown in FIG. 3A, the groove portion 14 which is formed by the pair of
long-side walls 12 and the pair of short-side walls 13 has a length corresponding to the
shortest distance L (refer to FIG. 1B) between both ends of the intermediate
press-formed product 51. That is, the lenglh of the groove portion 14 (the distance
between the wall surfaces 13a of the pair of short-side walls 13) is the same as the
shortest distance L between both ends of the intermediate press-formed product 51.
[0044]
As shown in FIG. 3B, the groove portion 14 has a width corresponding to a gap
between the pair of vertical wall portions 53 of the intermediate press-formed product
51. That is, the width (the distance between the wall surfaces 12a of the pair of
long-side walls 12) of the groove portion 14 is the same as the width ofthe intermediate
press-fanned product 51. In addition, a depth of the groove portion 14 is the same as
the width of the vertical wall portion 53 of the intermediate press-fonned product 51.
[0045]
In addition, as shown in FIG. 3B, the convex portion 23 of the punch portion 22
includes a pair of side surfaces 23a which is provided on both sides in the width
direction, and a distal surface 23b which faces the groove portion 14. When the upper
press tool 20 lowers and the upper press tool 20 and the lower press tool 10 approach
each other, the convex portion 23 of the punch portion 22 enters the groove portion 14
of the lower press tool 10. In addition, the convex portion 23 may be integrated with
the punch portion 22, and may be separated from the punch portion 22.
[0046]
The length of the convex portion 23 is less than or equal to the shortest distance
L of the intermediate press-formed product 51, and the width (the distance between the
pair of side surfaces 23a) of the convex portion 23 is the same as the distance between
the inner surfaces of the pair of vertical wall portions 53 of the intermediate
press-formed product 5 1.
[0047]
Next, a method for manufacturing the press-formed product 101 by the
intermediate press-formed product 51 using the manufacturing device 1 will be
described. First, as shown in FIG. 3A, the intermediate press-formed product 51 is
disposed immediately on the groove portion 14 of the lower press tool 10. At this time,
the intermediate press-formed product 5 1 is disposed such that the convex side
(extension side, refer to FIG. 1B) of the bending portion 52b of the intermediate
press-formed product 5 1 faces the upper press tool 20. Accordingly, the convex
portion 23 of the punch portion 22 can come into contact with the convex side of the
bending portion 52b. In addition, in the state where the intermediate press-formed
product 51 is disposed in the manufacturing device 1, the short sides 53a and 53b of the
vertical wall portion 53 of the intermediate press-formed product 51 come into contact
with the convex surfaces 13b of the short-side walls 13.
[0048]
Subsequently, as shown in FIG. 4A and 4B, the upper press tool 20 lowers, and
the intermediate press-formed product 51 is press-formed. At this time, since the
convex portion 23 of the punch portion 22 presses the convex side ofthe bending
portion 52b of the intermediate press-formed product 51, the curvature of the bending
portion 52b decreases, and the intermediate press-formed product 51 linearly extends.
Were, as described above, since the distance between the pair of short-side walls 13 is
the same as the shortest distance L between both ends of the intermediate press-formed
product 5 1 in the longitudinal direction, both ends of the intermediate press-formed
product 5 1 in the longitudinal direction are restricted by the pair of shoit-side walls 13.
Accordingly, by lowering the upper press tool 20, compressive stress is applied to the
intermediate press-formed product 5 1 in the longitudinal direction. Simultaneously, by
decreasing the curvaturc of the bending portion 52b, inclination angles of the short sides
53a and 53b of the intermediate press-formed product 51 gradually become
perpendicular. In this way, the intermediate press-formed product 51 is pushed into the
groove portion 14 while the short sides 53a and 53b come into contact with the convex
surface 13b.
[0049]
In the press forming, since the distance between the wall surfaces 13a of the
pair of short-side walls 13 is the same as the shortest distance L between both ends of
the intermediate press-formed product 5 1 in the longitudinal direction and the convex
side of the bending portion 52b of the intermediate press-formed product 5 1 is pressed,
it is possible to decrease the curvature of the bending portion 52b of the intermediate
press-formed product 51 while restricting both ends of the intermediate press-formed
product 51 in the longitudinal direction. As a result, since the entire length L1 (refer to
FIG. 1B) of the web portion 52 of the intermediate press-formed product 51 is longer
than the shortest distance L between both ends of the intermediate press-formed product
51 in the longitudinal direction, compressive stress is applied to the web portion 52 and
the vertical wall portions 53 of the intermediate press-formed product 5 1 in the
longitudinal direction, and it is possible to compress the intermediate press-formed
product 51 in the longitudinal direction. That is, thicknesses (cross-sectional areas) of
the web portion 52 and the vertical wall portion 53 of the intermediate press-formed
product 5 1 can increase by the compression of the intermediate press-formed product
51.
[0050]
In addition, when compressive stress is applied to the intermediate
press-formed product 5 1, as shown in FIG. 4B, since the web poi-tion 52 of the
intermediate press-fo~medp roduct 51 is interposed between the upper surface l l a of the
base portion 11 of the lower press tool 10 and the distal surface 23b of the convex
portion 23 of the upper press tool 20, it is possible to prevent buckling distortion of the
web portion 52. Similarly, since the vertical wall portions 53 of the intermediate
press-formed product 5 1' are interposed between the wall surfaces 12a (refer to FIG. 3B)
of the pair of long-side walls 12 of the lower press tool 10 and the side surfaces 23a of
the convex portion 23 of the upper press tool 20, it is possible to prevent buckling
distortion of the vertical wall portions 53. In addition, since the shoi-t sides 53a and
53b of the intermediate press-formed product 51 are pushed into the groove portion 14
while coming into contact with the convex surfaces 13b of the short-side walls 13, it is
possible to prevent buckling distortion of the end portions of the intermediate
press-formed product 5 1 in the longitudinal direction. Accordingly, the buckling
distortion of the web portion 52 and the vertical wall portions 53 of the intermediate
press-formed product 51 is prevented, and it is possible to increase the thicknesses of
the web portion 52 and the vertical wall portions 53.
[OOS 11
According to the above-described press forming, the press-formed product 101
is manufactured from the intermediate press-formed product 51.
[0052]
FIGS. 5A to 5C are views showing the press-formed product 101 according to
the present embodiment. In addition, FIG. 5A is a perspective view, FIG. 5B is a front
view, and FIG. 5C is a side view. As described above, the press-formed product 101 is
obtained by allowing the curvature of the bending portion 52b of the intermediate
press-formed product 5 1 to be zero while constricting both ends of the intermediate
press-formed product 5 1. Accordingly, as shown in FIGS. 5A to 5C, the press-formed
product 101 has a straight shape, and the entire length L' of the press-formed product
101 is the same as the shortest distance L between both ends of the intermediate
press-formed product 51 in the longitudinal direction.
[0053]
FIGS. 6A to 6C are sectional views taken along line A-A of FIG. 5C, and are
views showing examples in which the thickness of the press-formed product 101
increases (the cross-sectional area increases). FIG. 6A shows a case where an upper
surface 102a of the web portion 102 of the press-formed product 101 is a flat surface
and a lower surface 102b is a rising surface due to the increase in the thickness. As
shown in FIG. 6A, the web portion 102 of the press-formed product 101 includes a thick
section 102c (high cross-sectional area portion) having the thickest thickness, a thin
section 102d (low cross-sectional area portion) having a thickness which is thinner than
that ofthe thick section 102c, and an intermediate portion 102e which is provided
between the thick section 102c and the thin section 102d and in which the thickness
continuously changes along the longitudinal direction. In addition, when the
press-formed product 101 is viewed from the cross section perpendicular to the
longitudinal direction, the thick section 102c is a portion having the largest
cross-sectional area, and the thin section 102d is a portion having the smallest
cross-sectional area.
[0054]
Here, the bending portion 52b of the intermediate press-formed product 51
becomes the thick section 102c of the press-fonned product 101, and the linear portion
52a of the intermediate press-formed product 51 becomes the thin section 102d. In the
intermediate press-formed product 51, since the length of the bending portion 52b is
shorter than that of the linear portion 52a (refer to FIG. 1B), the length of the thin
section 102d is longer than the length of the thick section 102c.
[0055]
FIG. 6B shows a case where the lower surface 102b of the web portion 102 is a
flat surface and the upper surface 102a is a rising surface due to the increase in the
thickness. In addition, FIG. 6C shows a case where the upper surface 10221 and the
lower surface 102h of the web portion 102 are rising surfaces due to the increases in the
thicknesses.
[0056]
In addition, FIGS. 6D to 6F are bottom views of the press-formed product 101,
and views showing examples in which the thicknesses increase (the cross-sectional
areas increase). FIG. 6D shows a case where an outer surface 103a of each of the
vertical wall portions 103 is a flat surface and an inner surface 103b is a rising surface
due to the increase in the thickness. As shown in FIG. 6D, the vertical wall portion
103 includes a thick section 103c (high cross-sectional area portion) having the thickest
thickness, a thin section 103d (low cross-sectional area portion) having a thickness
which is thinner than that of the thick section 103c, and an intermediate portion 103e
which is provided between the thick section 103c and the thin section 103d and in
which the thickness continuously changes along the longitudinal direction. In addition,
similarly to the web portion 102, the length of the thin section 103d ofthe vertical wall
portion 103 is longer than the length of the thick section 103c.
[0057]
FIG. 6E shows a case where the inner surface 103b of the vertical wall portions
103 is a flat surface and the outer surface 103a is a rising surface due to the increase in
the thickness. In addition, FIG. 6F shows a case where the outer surface 103a and the
inner surface 103b of the vertical wall portion 103 are rising surfaces due to the
increases in the thicknesses.
[005S]
As shown in FIGS. 6A to 6F, whether each surface of the web portion 102 and
the vertical wall portions 103 of the press-formed product 101 is a flat surface or a
rising surface due to the increase in the thickness is determined by the gap between the
goove portion 14 of the lower press tool 10 and the convex portion 23 of the upper
press tool 20, the bottom dead center of the upper press tool 20, or the like.
[0059]
As described above, since the thick section 102c or the thick section 103c is
provided on the web portion 102 and the vertical wall portions 103 of the press-for~ned
product 101, and the thickness of each of the web portion 102 and the vertical wall
portions 103 partially increases (the cross-sectional area partially increases when
viewed from the cross section perpendicular to the longitudinal direction), it is possible
to increase rigidity of the press-formed product 101. In addition, since the
press-formed product 101 is manufactured by compressing the intermediate
press-formed prodnct 51 in the longitudinal direction, it is possible to increase yield
strength of the press-formed product 101 by work hardening.
In addition, since the intermediate portion 102e is provided between the thick
section 102c and the thin section 102d, it is possible to prevent stress from being
concentrated in a boundary between the thick section 102c and the thin section 102d.
[0060]
In addition, the thickness of the thick section 102c of the press-formed product
101 is determined by the entire length, the thickness, the curvature, the material, or the
like of the intermediate press-formed product 51. Preferably, the thickness of the
press-formed product 101 is 105% or more of the thickness of the intermediate
press-formed product 5 1, and more preferably, is 11 0% or more of the thickness of the
intermediate press-formed product 5 1. In addition, an upper limit of the thickness of
the thick section 102c of the press-formed product 101 is not particularly limited.
However, the upper limit of the thickness of the thick section 102c may be 140% or less
of the thickness of the intermediate press-formed product 5 1, may be 135% or less
thereof, and may be 130% or less thereof.
[0061]
In addition, since the length of the thin section 102d is longer than the length of
the thick section 102c, it is possible to increase the rigidity of only a necessary portion,
and it is possible to decrease weight of the component. Similarly, since the length of
the thin section 103d is longer than the length of the thick section 103c, it is possible to
increase the rigidity of only a necessary portion, and it is possible to decrease the weight
of the component.
[0062]
For example, the pressiformed product 101 can be suitably used in an
automobile component such as center pillar reinforcement, a floor cross member, or
locker reinforcement.
[0063]
In the present embodiment, the case is described, in which the straight
press-formed product 101 is manufactured by allowing the curvature of the bending
portion 52b of the intcrmediate press-formed product 5 1 to be zero. However, the
present embodiment is not limited to this, and the press-formed product 101 may be
manufactured by decreasing the curvature of the bending portion 52b of the
intermediate press-formed product 51 to a predetermined curvature. That is, the
curvature of the bending portion 52b subjected to the press forming is not limited to
only zero, and may be any curvature as long as it is smaller than the curvature ofthe
bending portion 52b before the press forming.
[0064]
As described above, according to the present embodiment, the intermediate
press-formed product 51 having the bending portion 52b is prepared, the intermediate
press-formed product 51 is compressed along the longitudinal direction by decreasing
the culvature of the bending portion 52b of the intermediate press-formed product 51
while constantly maintaining the shortest distance between both ends of the
intermediate press-formed product 5 1 in the longitudinal direction, and the material
becomes a surplus by the compression. Accordingly, the thickness (cross-sectional
area) of a portion of the web portion 52 increases due to the surplus material.
Simultaneously, the thickness (cross-sectional area) of a portion of the vertical wall
portion 53 also increases. In this way, it is possible to manufacture the press-formed
product 101 which includes the web portion 102 and the vertical wall portions 103
having the increased thickness (increased cross-sectional area) without performing
welding, is lightweight, and has high rigidity.
[0065]
In addition, in the present embodiment, the case is described in which the
distance between the pair of short-side walls 13 of the manufacturing device 1 is the
same as the shortest distance L of the intermediate press-formed product 5 1. However,
the distance between the pair of short-side walls 13 of the manufacturing device 1 may
be any distance as long as it is smaller than the entire length L1 (the lcngth in a case
where the intermediate press-formed product 51 linearly extends) of the intermediate
press-formed product 5 1. In this case, since the intermediate press-formed product 5 1
can be compressed aloiig the longitudinal direction, it is possible to manufacture the
press-formed product 10 1 having the increase thickness without performing welding.
[0066]
[Modification Example of Press-formed Product]
In the present embodiment, the case is described in which the press-formed
product 101 is manufactured by the inteimediate press-formed product 51. Howevel;
it is possible to manufacture various press-formed products using other intermediate
press-formed products instead of the intermediate press-formed product 5 1. FIGS. 7A
to 7C are view showing an intermediate press-formed product 61. In addition, FIG. 7A
is a perspective view, FIG. 7B is a fiont view, and FIG. 7C is a side view. As shown in
FIGS. 7A to 7C, similarly to the intermediate press-formed product 51, the intermediate
press-formed product 61 includes a web portion 62 and a pair of vertical wall portions
63. Here, the web portion 62 of the intermediate press-formed product 61 is
configured of a bending portion 62b, and the entire web portion 62 has a curved shape.
[0067]
FIG. 8 is a view showing a state where the intermediate press-formed product
61 is disposed in the manufacturing device 1. Similarly to the case where the
press-formed product 101 is manufactured, it is possible to compress the intermediate
press-formed product 61 along the longitudinal direction by lowering the upper press
tool 20 of the manufacturing device 1. FIGS. 9A and 9B are view showing a
press-formed product 11 1 which is manufactured by the intermediate press-formed
product 61. In addition, FIGS. 9C to 9H show examples in which thicknesses of a web
portion 112 and vertical wall portions 113 of the press-formed product 11 1 increase.
[0068]
FIGS. 9C to 9E are sectional views taken along line B-B of FIG. 9B. In FIG.
9C, an upper surface 112a of the web portion 112 is a flat surface and a lower surface
112b is a rising surface due to the increase in the thickness. The web portion 112
includes a thick section 112c having the thickest thickness, a thin section 112d having a
thickness which is thinner than that of the thick section 112c, and an intermediate
poi-tion 112e which is provided between the thick section 112c and the thin section 112d
and in which the thickness continuously changes.
[0069]
FIG. 9D shows a case where the lower surface 112b of the web portion 112 is a
flat surface and the upper surface 112a is a rising surface due to the increase in the
thickness. In addition, FIG. 9E shows a case where the upper surface 112a and the
lower surfaces 112b of the web portion 112 are rising surfaces due to the increase in the
thicknesses.
[0070]
FIGS. 9F to 9H show bottom views of the press-formed product 11 1. In FIG.
9F, an outer surface 11 3a of each of the vertical wall pol-tions 113 is a flat surface, and
the inner surface 113b is a rising surface due to the increase in the thickness. The
vertical wall portion 113 includes a thick section 113c having the thickest thickness, a
thin section 113d having a thickness which is thinner than that of the thick section 113c,
and an intermediate portion 113e which is provided between the thick section 113c and
the thin section 113d and in which the thickness continuously changes.
[0071]
FIG. 9G shows a case where the inner surface 113b of each of the vertical wall
portion 113 is a flat surface and the outer surface 113a is a rising surface due to the
increase in the thickness. In addition, FIG. 9H shows a case where the inner surface
113b and the outer surface 113a of the vertical wall portion 113 are rising surfaces due
to the increases in the thicknesses.
[0072]
In addition, in the manufacturing device 1, an intermediate press-formed
product 7 1 shown in FIGS. 1 OA to 10C can be used. As shown in FIGS. 10A to 1 OC,
the inteimediate press-formed product 71 includes a web portion 72, a pair of vertical
wall portions 73 which is connected to both sides of the web portion 72 in the width
direction, and a flanged portion 74 which is connected to each of the pair of vertical
wall portions 73. In addition, the intermediate press-formed product 71 is different
from the intermediate press-formed product 51 (refer to FIGS. 1A to ID) in that the
flanged portions 74 are provided.
[0073]
FIGS. 1 lA and 11B are views showing a state where the intermediate
press-formed product 71 is disposed in the manufacturing device 1, and FIGS. 12A and
12B are views showing the upper press tool 20 of the manufacturing device 1 is lowered
to the bottom dead center. Similarly to the case where the press-formed product 101 is
manufactured, the intermediate press-formed product 71 can be compressed along the
longitudinal direction by lowering the upper press tool 20 of the manufacturing device 1.
In addition, as shown in FIG. 12B, the flanged portions 74 of the intermediate
press-formed product 71 are interposed between the punch portion 22 and the upper
surfaces of the long-side walls 12 so as to be restricted during the press forming.
Accordingly, it is possible to prevent wrinkles from occurring on the flanged portions
74.
[0074]
Moreover, in the manufacturing device 1, an intermediate press-formed product
8 1 shown in FIGS. 13A to 13C can be used. As shown in FIGS. 13A to 13C, the
intermediate press-formed product 81 includes a web poi-tion 82 and a pair of vertical
wall portions 83 which is connected to both sides of the web portion 82 in the width
direction. In addition, the intermediate press-forn~edp roduct 8 1 is different from the
intermediate press-formed product 51 (refer to FIGS. lA to ID) in that it includes three
linear portions 52a and two bending portions 52b.
[0075]
FIG. 14 shows a state where the intermediate press-formed product 81 is
disposed in the manufacturing device 1. By lowering the upper press tool 20 from the
state shown in FIG. 14, it is possible to compress the intermediate press-formed product
81 in the longitudinal direction. In addition, it is possible to manufacture a
press-formed product 13 1 which is shown in FIGS. 15A and 15B from thc intermediate
press-formed product 81. FIGS. 15C to 15H show examples in which thicknesses of a
web portion 132 and vertical wall portions 133 of the press-formed product 13 1
increase.
LO0761
FIGS. 15C to 15E are sectional views taken along line C-C of FIG. 15B. In
FIG. 15C, in a state where an upper surface 132a of the web portion 132 is a flat surface,
a lower surface 132h is a rising surface due to the increase in the thickness. The web
portion 132 includes a thick section 132c, a thin section 132d, and an intermediate
portion 132e which is provided between the thick section 132c and the thin section 132d
and in which the thickness continuously changes along the longitudinal direction. In
addition, thick sections 132c are provided at two locations, and thin sections 132d are
provided at three locations. In addition, the thick sections 132c are provided at the
positions corresponding to the bending portions 52b of the intermediate press-formed
product 8 1, and the thin sections 132d are provided at the positions corresponding to the
linear portions 52a of the intermediate press-formed product 81.
[0077]
FIG. 150 shows a case where the upper surface 132a is a rising surface due to
the increase in the thickness in a state where the lower surface 132b of the web portion
132 is a flat surface. In addition, FIG. 15E shows a case where the upper surface 132a
and the lower surfaces 132b of the web portion 132 are rising surfaces duc to the
increase in the thicknesses.
[0078]
FIGS. 15F to 15H show bottom views of the press-formed product 13 1. In
FIG. 15F, in a state where an outer surface 133a of each of the vertical wall portions 133
is a flat surface, an inner surface 133b is a rising surface due to the increase in the
thickness. In the vertical wall portion 133, a thick section 133c, a thin section 133d,
and an intermediate portion 133e which is provided between the thick section 133c and
the thin section 133d are provided. Thick sections 133c are provided at two locations,
and thin sections 133d are provided at three locations. The thick sections 133c are
provided at the positions corresponding to the bending portions 52b of the intermediate
press-formed product 81, and the thin sections 133d are provided at the positions
corresponding to the linear portions 52a of the intermediate press-formed product 81
[0079]
FIG. 15G shows a case where the outer surface 133a is a rising surface due to
the increase in the thickness in a state where the inner surface 133b of each of the
vertical wall portions 133 is a flat surface. FIG. 15H shows a case where the outer
surface 133a and the inner surface 133b of each of the vertical wall portions 133 are
rising surfaces due to the increases in the thicknesses.
[0080]
In addition, in the manufacturing device 1, as shown in FIGS. 16A and 16B, an
intermediate press-formed product 141 having a bending portion 141b and linear
portions 141a can be used. Moreover, the cross section of the intermediate
press-formed product 141 is solid and circular. In this case, by press-forming the
intermediate press-formed product 141 using the manufacturing device 1, it is possible
to manufacture a press-foimed product in which a cross-sectional area increases and the
cross section is solid and circular.
[0081]
In addition, as shown in FIGS. 17A and 17B, an intermediate press-formed
product 143 having a bending portion 143b and linear portions 143a can be used. In
addition, the cross section of the intermediate press-formed product 143 is solid and
rectangular. In this case, by press-forming the intermediate press-formed product 143
using the manufacturing device 1, it is possible to manufacture a press-formed product
in which a cross-sectional area increases and the cross section is solid and rectangular.
[0082]
Moreover, as shown in FIGS. 18A and 18B, an intermediate press-formed
product 145 having a bending portion 145b and linear portions 14% can be used. In
addition, the cross section of the intermediate press-formed product 145 is hollow and
circular. In this case, by press-forming the intermediate press-formed product 145
using the manufacturing device 1, it is possible to manufacture a press-formed product
in which a cross-sectional area increases and the cross section is hollow and circular.
[0083]
In addition, as shown in FIGS. 19A and 19B, an intermediate press-formed
product 147 having a bending portion 147b and Iinear portions 147a can be used. In
addition, the cross section of the intermediate press-fol.ined product 147 is hollow and
elliptical. In this case, by press-forming the intermediate press-fo~nled product 147
using the manufacturing device 1, it is possible to manufacture a press-formed product
in which a cross-sectional area increases and the cross section is hollow and elliptical.
[0084]
Moreover, as shown in FIGS. 20A and 20B, an intermediate press-formed
product 15 1 having a bending portion 15 1 b and linear portions 15 la can be used. In
addition, the cross section of the intermediate press-formed product 151 is solid and
rectangular. In surfaces of the bending portion 151b, one oftwo side surfaces
perpendicular to the width direction is a surface (extension surface) which is extended
by bending, and the other of two side surfaces is a surface (constriction surface) which
is constricted by bending. The intermediate press-formed product 151 is disposed in
the manufacturing device 1 such that the extension surface of the bending portion 15 1 b
faces the upper press tool 20. In this case, by press-forming the intermediate
press-formed product 15 1 using the manufacturing device 1, it is possible to
manufacture a press-formed product in which a cross-sectional area increases and the
cross section is solid and rectangular.
[0085]
In addition, as shown in FIGS. 21A and 21B, an intermediate press-formed
product 153 having a bending portion 153b and linear portions 153a can be used. In
addition, the cross section of the intermediate press-formed product 153 is solid and
rectangular. In surfaces of the bending portion 153b, one of two side surfaces
perpendicular to the width direction is a surface (extension surface) which is extended
by bending, and the other of two side surfaces is a surface (constriction surface) which
is constricted by bending. The intermediate press-formed product 51 is disposed in the
manufacturing device 1 such that the extension surface of the bending portion 153b
faces the upper press tool 20. In this case, by press-forming the intermediate
press-formed product 153 using the manufacturing device 1, it is possible to
manufacture a press-fanned product in which a cross-sectional area increases and the
cross section is solid and rectangular.
[0086]
In addition, as sho\vn in FIGS. 22A and 22B, an intermediate press-formed
product 155 which includes a bending portion 155b and linear portions 155a and has an
L-shaped cross section can bc used. In this case, by press-forming the intermediate
press-formed product 155 using the manufacturing device 1, it is possible to
ma~lufacturea press-fonned product in which a cross-sectional area increases and which
has a L-shaped cross section.
[O087]
In addition, as shown in FIGS. 23A and 23B, an intermediate press-formed
product 157 which includes a bending portion 157b and linear portions 157a and has a
Z-shaped cross section can be used. In this case, by press-forming the intermediate
press-formed product 157 using the manufacturing device 1, it is possible to
manufacture a press-formed product in which a cross-sectional area increases and which
has a Z-shaped cross section. At this time, in order to prevent buckling distortion
during press working, as shown in FIG 23B, preferably, one of the pair of long-side
walls 12 of the manufacturing device 1 is formed in an L shape.
[OOSS]
(Second Embodiment)
Next, a second embodiment of the present invention will be described.
[0OS9]
FIGS. 24A and 24B are views showing an intermediate press-formed product
251 which is used in the second embodiment. In addition, FIG. 24A is a perspective
view and FIG. 24B is a front view. As shown in FIGS. 24A and 24B, the intermediate
press-formed product 25 1 is steel (long material) which is long in one direction, and is
configured of a web portion 252, and a pair of vertical wall portions 253 which are
provided on both sides of the web portion 252 in a width direction. The web portion
252 includes two linear portions 252a and a bending portion 252b which is provided
between the two linear portions 252a. The bending portion 252b is a portion which is
provided on the center portion of the web portion 252 in a longitudinal direction and is
curved in an arc shape. In surfaces of the bending portion 252b, a surface which is
extended by bending is an extension surface, and the other surface (a surface which is
constricted by bending) is a constriction surfaced. The second embodiment is different
from the first embodiment in that the pair of vertical wall portions 253 is provided on
the constriction surface of the bending portion 252b. In addition, a short side 253a and
a short side 253b of each of ihe verlical wall pollions 253 of the intermediate
press-formed product 25 1 are parallel with each other. That is, planes including end
edges of both ends of the intermediate press-formed product 251 in the longitudinal
direction are parallel with each other.
[009O]
A steel sheet is prcss-formed, bending is performed on the steel sheet, and
thereaftel; the intermediate press-formed product 251 can be obtained by cutting both
ends of the vertical wall portions 253 of the intermediate press-for~nedp roduct 251 in
the longitudinal direction. In addition, before the steel sheet is press-formed, template
may be performed on the stcel sheet in advance.
[0091]
FIGS. 25A and 25B are views showing a device 200 for manufacturing a
press-forincd product (hereinafter, simply referred to as a manufacturing device 200)
according to the second embodiment. In addition, F1G. 25A is a perspective view, and
FIG. 25B is a side view. In the manufacturing device 1 according to the first
embodiment, the upper press tool 20 includes the punch portion 22 having the convex
portion 23, and the lower press tool 10 includes the pair of short-side walls 13 and the
pair of long-side walls 12. Meanwhile, in the manufacturing device 200 according to
the second embodiment, an upper press tool 220 includes a punch portion 222 which
has a concave portion 223, and a lower press tool 210 includes a convex portion 214
which is provided on the base portion 11 instead of the pair of long-side walls 12. In
addition, in the manufacturing device 200, the main body portion 21 (refer to FIG. 2) is
not shown.
[0092]
The width of the concave portion 223 of the punch portion 222 of the upper
press tool 220 is the same as the entire width of the intermediate press-formed product
251. The length of the concave portion 223 is the same as a distance between the pair
of short-side walls 13, and is the same as a distance (shortest distance) between both
ends of the intermediate press-formed product 25 1 in the longitudinal direction. The
depth of the concave portion 223 is a width of each of the vertical wall porlions 253 of
the intermediate press-formed product 25 1.
[0093]
The width of the convex portion 214 of the lower press tool 210 is the same as
a distance between inner surfaces of the pair of vertical wall portions 253 of the
intermediate press-formed product 251. The length of the convex poltion 214 is the
same as a distance between the pair of short-side walls 13, and is the same as the
distance L between both ends of the intermediate press-formed product 25 1 in the
longitudinal direction.
[0094]
FIG. 26 is a front view showing a state where the intermediate press-formed
product 25 1 is disposed in the manufacturing device 200. 111 addition, in FIG. 26, the
upper press tool 220 is shown in a longitudinal scctional view. As shown in FIG. 26,
the intermediate press-formed product 25 1 is disposed immediately on the convex
portion 214 such that the convex portion 214 of the lower press tool 210 is interposed
between the pair of vertical wall portions 253 of the intermediate press-formed product
251. At this time, since the distance between the pair of short-side walls 13 is the
same as the distance L between both ends of the intermediate press-formed product 251
in the longitudinal direction, both ends of the intermediate press-formed product 251 in
the longitudinal direction are restricted. In addition, as described above, since both
ends of the intermediate press-formed product 251 in the longitudinal direction are
parallel with each other, the intermediate press-formed product 25 1 can be disposed
such that both ends of the intermediate press-formed product 25 1 in the longitudinal
direction are parallel with the pair of short-side walls 13. Accordingly, it is possible to
equally apply a load to the intermediate press-formed product 251 when the
intermediate press-formed product 25 1 is press-formed, and as a result, it is possible to
prevent buckling distortion of the intermediate press-formed product 25 1.
[0095]
FIGS. 27A and 27B are views showing a state where the upper press tool 220 is
lowered to the bottom dead center. In addition, FIG. 27A is a front view, and FIG. 27B
is a side view. Similarly to the case of the first embodiment, by lowering the upper
press tool 220, the curvature of the bending portion 252b of the intermediate
press-formed product 25 1 decreases while both ends of the intermediate press-formed
product 25 1 in the longitudinal direction are restricted. As a result, it is possible to
compress the intermediate press-formed product 251 in the longitudinal direction, and
the thicknesses of the web portion 252 and the vertical wall portions 253 of the
intermediate press-formed product 25 1 increase.
[0096]
In the present embodiment, as shown in FIG. 27B, press forming is performed
such that the curvature of the bending portion 252b of the intermediate press-formed
product 251 decrease while the intermediate press-formed product 251 is interposed
between the concave portion 223 of the upper press tool 220 and the convex portion 214
of the lower press tool 210. Accordingly, when compressive stress is applied to the
intermediate press-formed product 25 1 in the longitudinal direction, since the web
portion 252 of the intermediate press-formed product 251 is interposed between a
bottoin surface 223a of the concave portion 223 of the upper press tool 220 and an
uppel surface 214a of the convex portion 214 of the lower press tool 210, it is possible
to prevent buckling distortion of the web portion 252. Similarly, since the vei-tical wall
portions 253 of the intermediate press-formed product 251 are interposed between side
surfaces 223b of the concave portion 223 of the upper press tool 220 and side surfaces
214b of the convex portion 214 of the lower press tool 210, it is possible to prevent
buckling distol-tion of the vertical wall portions 253.
[0097]
In addition, in the manufacturing device 200, an intermediate press-formed
product 261 shown in FIGS. 28A to 28D can be used. As shown in FIGS. 28A to 28D,
the intermediate press-formed product 261 includcs a web portion 262 and a pair of
vertical wall portions 263. Here, the web portion 262 of the intermediate press-formed
product 261 is configured of a bending portion 262b, and the entire web portion 262 has
a curved shape. In addition, sinlilarly to the intermediate press-formed product 251,
short sides 263a and 2631, of the vertical wall portions 263 of the intermediate
press-formed product 261 are parallel with each other.
[0098]
FIG. 29 is a view showing a state where the intermediate press-formed product
261 is disposed in the manufacturing device 200. Similarly to the intermediate press
251, the intermediate press-formed product 261 is compressed by lowering the upper
press tool 220 in the longitudinal direction, and the thicknesses of the web portion 262
and the vertical wall portions 263 increase.
[0099]
(Third Embodiment)
Next, a third embodiment of the present invention will be described.
[O 1001
FIG. 30A and 30B are views showing a device 300 for manufacturing a
press-formed product (hereinafter, simply referred to as a manufacturing device 300)
according to the third embodiment. The manufacturing device 300 according to the
present embodiment is different from the manufacturing device 1 according to the first
embodiment in that a blank holder pad 331 (blank holder tool) is provided.
[OlOl]
As shown in FIGS. 30A and 30B, the blank holder pad 33 1 is inserted into a
through hole 1 lb which is provided in the base portion 11 of the lower press tool 10.
The blank holder pad 33 1 can be freely lifted and lowered in accordance with the
movements of the upper press tool 20 and the lower press tool 10, and can be
acconlmodated in the through hole 11 b.
[O 1021
FIGS. 32A to 32C are views showing the blank holder pad 331. As shown in
FIGS. 32A to 32C, the blank holder pad 33 1 is configured of a main body portion 33 la
and a shaft portion 331b which is connected to thc main body portion 331a. The shaft
portion 331b is inserted into the through hole 1 lb which is provided in the lower press
tool 10.
[0103]
The main body portion 331a of the blank holder pad 33 1 includes an upper
surface 331c and side surfaces 33 Id. The upper surface 331c is a convex surface
which is provided on the apex portion of the main body portion 33 la and comes into
contact with the bending portion 52b of the web portion 52 of the intermediate
press-formed product 5 1. Each of the side surfaces 33 1 d is a flat surface which is a
side portion of the main body portion 33 la. In addition, the upper surface 331c has a
curvature which is smaller than the curvature of the bending portion 52b (refer to FIG.
1B) of the inte~mediatep ress-formed product 51. Accordingly, it is possible to prevent
buckling of the web portion 52 of the intermediate press-formed product 5 1.
[O 1041
As shown in FIGS. 30A and 30B, when the intermediate press-formed product
51 is press-formed using the manufacturing device 300, after both ends of the
intermediate press-formed product 5 1 come into contact with the convex surfaces 13b of
the lower press tool 10, the blank holder pad 33 1 is lifted toward the intermediate
press-formed product 51, and the blank holder pad 33 1 comes into contact with the
bending portion 52b of the web portion 52 of the intermediate press-formed product 51.
At this time, the blank holder pad 33 1 comes into contact with the concave side
(constriction surface) of the bending portion 52b of the intermediate press-formed
product 5 1. Thereafter, the upper press tool 20 lowers, and the convex portion 23 of
the upper press tool 20 comes into contact with the convex side (extension surface) of
the bending portion 52b of the web portion 52 of the intermediate press-formed product
51. In addition, by further lowering the upper press tool 20, as shown in FIGS. 3 1A
and 3 lB, the intermediate press-formed product 5 1 is compressed in the longitudinal
direction while the web portion 52 of the intermediate press-formed product 51 is held
by the blank holder pad 33 1 and the upper press tool 20. Moreover, as described
above, since the blank holder pad 331 can be freely lifted and lowered, the blank holder
pad 331 is lowered while being pressed by the upper press tool 20. Since the blank
holder pad 33 1 is lowered while being pressed by the upper press tool 20 in the state
where the blank holder pad 33 1 comes into contact with the web portion 52 ofthe
intermediate press-formed product 51, it is possible to prevent buclcling distortion of the
web portion 52 of the intermediate press-formed product 51.
[0105]
In addition, in the manufacturing device 300, instead of the inte~mediate
press-formed product 51, an intermediate press-formed product 351 shown in FIGS.
33A to 33C can be used. As shown in FIGS. 33A to 33C. the intermediate
press-formed product 351 includes a web portion 352, and a pair of vertical wall
portions 353 which is connected to both sides ofthe web portion 352 in the width
direction. In addition, the intermediate press-formed product 351 is different from the
intermediate press-formed product 251 (refer to FIGS. 24A and 24B) in that four linear
portions 252a, one bending portion 252b, and two bending portions 352c are provided.
Moreover, each of the bending portions 352c of the intermediate press-formed product
351 protrudes in a direction opposite to the direction in which the bending portion 252b
protrudes.
[0 1061
FIG. 34A is a view showing a state where the intermediate press-formed
product 351 is disposed in the manufacturing device 300. In addition, FIG. 34B is a
view showing a state where the upper press tool 20 of the manufacturing device 300 is
lowered to the bottom dead center. Similarly to the case where the intermediate
press-formed product 51 is press-formed using the manufacturing device 300, by
lowering the upper press tool 20, it is possible to compress the intermediate
press-formed product 35 1 in the longitudinal direction. At this time, the upper surface
33 1c of the blank holder pad 33 1 comes into contact with the bending portion 2521, of
the web portion 352 of the intermediate press-formed product 351, and the side surfaces
331d come into contact with the inner surfaces of the vertical wall portions 353 of the
intermediate press-formed product 351. Accordingly, it is possible to prevent buckling
distortion of the intermediate press-formed product 351.
[0107]
Moreover, in the manufacturing device 300, an intermediate press-formed
product 361 shown in FIGS. 35A to 35C can be used. The intermediate press-formed
product 361 includes a web portion 362 and a pair of vertical wall portions 363 which is
connected to both sides of the web portion 362 in the width direction. In addition, in
the intermediate press-formed product 361, the bending portion 252b of the
intermediate press-formed product 351 is positioned to be biased toward one end side.
That is, the intermediate press-formed product 361 is different from the intermediate
press-folmcd product 35 1 shown in FIGS. 33.4 to 33C with respect to the position of the
bending portion 252b.
[OlOX]
FIG. 36 is a view showing the intermediate press-folmed product 361 and the
manufacturing device 300. When the intermediate press-formed product 361 is
press-formed, the blank holder pad 33 1 is disposed such that the upper surface 33 1c of
the blank holder pad 33 1 coines into contact with the bending portion 252b of the
intermcdiate press-formed product 361. In this way, by disposing the blank holdcr pad
33 1, similarly to the intermediate press-formed product 351, it is possible to prevent
buckling distortion of the intermediate press-formed product 361.
[0 1091
(Fourth Embodiment)
Next, a fourth embodiment of the present invention will be described.
[OllO]
FIGS. 37A and 37B are views showing a device 400 for manufacturing a
press-formed product (hereinaftel; referred to as a manufacturing device 400) according
to the fourth embodiment. The third embodiment shows the case where the
manufacturing device 300 includes one blank holder pad 33 1. Meanwhile, as shown in
FIGS. 37A and 37B, the manufacturing device 400 according to the present
embodiment includes three blank holder pads 33 1.
[Olll]
FIG. 38 is a view showing a state where the intermediate press-formed product
51 is press-formed using the manufacturing device 400. As described above, since the
manufacturing device 400 includes three blank holder pads 33 1, it is possible to more
reliably prevent buckle of the web portion 52 and the vertical wall portions 53 of the
intermediate press-formed product 51. In addition, the number of the blank holder
pads 33 1 may be two, or four or more.
[0112]
In addition, in the manufacturing device 400, an intermediate press-formed
product 451 shown in FIGS. 39A to 39C can be used. The intermediate press-formed
product 451 includes a web portion 452 and a pair of vertical wall portions 453 which is
connected to both sides of the web portion 452 in the width direction. In addition, the
intermediate press-formed product 45 1 is different from the intermediate press-formed
product 251 (refer to FIGS. 24A and 24B) in that three linear portions 252a and two
bending portions 252b are provided.
[0113]
FIGS. 40A and 40B are view showing a state where the intermediate
press-formed product 451 is disposed in the manufacturing device 400. As shown in
FIGS. 40A and 40B, when the intermediate press-fornled product 451 is press-formed,
the blank holder pads 33 1 are disposed such that the upper surfaces 331c of the blank
holder pads 33 1 come into contact with the bending portions 252b of the intern~ediate
press-formed product 451. That is, two among three blank holder pads 33 1 are
disposed so as to come into contact with the bending portions 252b, and the remaining
one is disposed so as to come into contact with the linear portion 252a.
[0114]
FIG. 41 is a view showing a state where the intermediate press-formed product
45 1 is press-formed. As shown in FIG. 41, the web portion 452 of the intermediate
press-formed product 451 are interposed between the upper press tool 20 and the blank
holder pads 33 1, and the vertical wall portions 453 of the intermediate press-formed
product 451 are interposed between the lower press tool 10 and the blank holder pads
33 1. Accordingly, it is possible to prevent buckling distortion of the intermediate
press-formed product 45 1.
[0115]
Moreover, in the manufacturing device 400, an intermediate press-formed
product 461 shown in FIGS. 42A to 42C can be used. The intermediate press-formed
product 461 includes a web portion 462 and a pair of vertical wall portions 463 which is
connected to both sides of the web portion 462 in the width direction. In addition, the
intermediate press-formed product 461 is different from the intermediate press-formed
product 351 (refer to FIGS. 33A to 33C) in that five linear portions 252a and two
bending portions 252b are provided.
[0116]
(Fifth Embodiment)
Next, a fifth embodiment of the present invention will be described.
[0117]
FIG. 43 is a front view showing a device 500 for manufacturing a press-formed
product (hereinafter, simply referred to as a manufacturing device 500) according to the
fifth embodiment. As shown in FIG. 43, the manufacturing device 500 is different
from the manufacturing device 200 according to the second embodiment in that a
mandrel 510 which is positioned between the pair of short-side walls 13 is provided.
[0118]
FIG. 44 is a front view showing the mandrel 5 10 according to the present
embodiment and the intermediatc press-formed product 251. In addition, FIG. 45 is a
front schematic view showing the mandrel 510. As shown in FIGS. 44 and 45, the
mandrel 5 10 is configured of a plurality of division bodies 5 11 and connection bodies
520 which connect the division bodies 5 11. The plurality of division bodies 5 11 of the
mandrel 5 10 are inserted into a space which is surrounded by the web portion 252 and
the pair of vertical wall portions 253 of the intermediate press-formed product 25 1. At
this time, among the plurality of division bodies 5 11, a division body 51 1X which is
positioilcd at the center in the longitudinal direction comes into contact with the
concave side (constriction surface) of the bending portion 252b of the wcb portion 252
of the intermediate press-formed product 251. In addition, a shaft portion 51 5, which
is inserted into a through hole provided at the center of the convex portion 214 of the
lower press tool 210 in the longitudinal direction, is connected to the division body
511X (refer to FIG. 43). Accordingly, the mandrel 510 can be freely lifted and lowered
in accordance with the movement of the upper press tool 220.
[0119]
In addition, the entire length of the mandrel 5 10 is set so as to be less than or
equal to the distance L (refer to FIGS. 24A and 24B) between both ends of the
intermediate press-formed product 251 in the longitudinal direction. In other words,
the entire length of the mandrel 510 is set so as to be less than or equal to the distance
between the pair of short-side walls 13. The setting is realized so as to prevent
interference between the mandrel 5 10 and the pair of short-side walls 13 when the
division bodies 5 11 of the mandrel 5 10 are arranged in a line (refer to FIG. 49).
[O 1201
In addition, as shown in FIG. 45, each of the division bodies 51 1 includes an
upper surface 5 11b which comes into contact with the web portion 252 of the
intermediate press-formed product 25 1, and side surfaces 5 11 c which come into contact
with the vertical wall portions 253 of the intermediate press-formed product 251. The
upper surface 5 11 b of the division body 5 11 is a convex surface, and the side surface
5 11 c of the division body 51 1 is a flat surface.
[0121]
FIG. 46 is an enlarged front view showing the mandrel 510. As shown in FIG.
46, each of the division bodies 5 11 of the mandrel 51 0 includes concave portions 5 13
which are provided on end portions of the division body 51 1 in the longitudinal
direction and stoppers 5 14 which are provided on inner surfaces of the concave portions
5 13. In the concave portion 513, an engagement portion 522 of the connection body
520 connected to the adjacent division body 511 is inserted to the inside further relative
to the stopper 514. The stopper 514 is a protrusion which is provided in the concave
poition 5 13 of the division body 5 11, and regulates the movement of the engagement
portion 522 of the connection body 520.
[0122]
FIG. 47 is a perspective view showing the connection body 520. As shown in
FIG. 47, the connection body 520 is configured of a rod-shaped main body portion 521,
and the ball-shaped engagement portion 522 which is provided on each of both ends of
the main body portion 521 in the longitudinal direction.
[0123]
In addition, instead of the connection body 520 shown in FIG. 47, as shown in
Fig. 48, a connection body 525 may be used, which is configured of a plate-shaped
main body portion 526, and a colun~naer ngagement portion 527 which is provided on
each of both ends of the main body portion 526 in the longitudinal direction.
[0 1 241
According to this configuration, the plurality of division bodies 51 1 of the
mandrel 5 10 can approach each other or can be separated fiom each other. That is, as
shown in FIG. 43, the plurality of division bodies 51 1 can be arranged in an arc shape or
arranged linearly (in a line) along the shape of the intermediate press-formed product
251.
[0125]
FIG. 49 is a front view showing the manufacturing device 500, and is a view
showing a state where the upper press tool 220 is lowered to the bottoni dead center.
When the upper press tool 220 is lowered, the mandrel 5 10 is lowered while being
pressed by the upper press tool 220. Accordingly, since the state where the mandrel
510 comes into contact with the web portion 252 and the vertical wall portions 253 of
the intermediate press-formed product 25 1 is maintained while the mandrel 510 is
lowered while being pressed by the upper press tool 220, it is possible to prevent
buckling distortion of the web portion 252 and the vertical wall portions 253 during
processing.
In addition, in the mandrel 510, the shape of the arrangement of the division
bodies 5 11 is changed fiom an arc shape to a line shape (a positional relationship
between the division bodies is changed) in accordance with the distortion of the web
portion 252 of the intermediate press-formed product 251. Accordingly, while the
upper press tool 220 is lowered to the bottom dead center, it is possible to allow the
mandrel 5 10 to come into contact with the web portion 252 and the vertical wall
portions 253 of the intermediate press-formed product 251.
[0126]
In this way, in the manufacturing device 500, since the intermediate
press-formed product 25 1 is press-formed while the mandrel 5 10 comes into contact
with the web portion 252 and the vertical wall portions 253 of the intermediate
press-formed product 25 1, it is possible to reliably prevent buckling distortion of the
web portion 252 and the vertical wall portions 253.
[0 1271
(Sixth Embodiment)
Ncxt, a sixth embodiment of the present invention will be described.
[0128]
FIG. 50 is a front view showing a device 600 for manufacturing a press-formed
product (hereinafter, simply referred to as a manufacturing device 600) according to the
sixth embodiment. In the fifth embodiment, the manufacturing device 500 includes
the mandrel 510. However, in the present embodiment, the manufacturing device 600
includes a mandrel 610 instead of the mandrel 510. Here, it is necessary to set the
entire length of the mandrel 510 according to the fifth embodiment to be less than or
equal to the distance between the pair of short-side walls 13. Accordingly, when the
intermediate press-formed product 25 1 is press-formed, a portion of the web portion
252 and the vertical wall portions 253 of the intermediate press-formed product 25 1
does not come into contact with the mandrel 5 10. Meanwhile, as described below,
since the entire length of the mandrel 610 according to the present embodiment can
increase and decrease, the entireties of the web portion 252 and the vertical wall
portions 253 of the intermediate press-formed product 251 can always come into
contact with the mandrel 61 0.
[0129]
FIG 51 is an enlarged front view showing the mandrel 61 0. As shown in FIG
51, the mandrel 610 according to the present embodiment is different from the mandrel
5 10 according to the fifth embodiment in that a plurality of division bodies 61 1 include
slider bodies 616 and elastic bodies 617.
[0130]
As shown in FIG. 51, each of the division bodies 61 I of the mandrel 610 is
configured of concave portions 613 which are provided on end pol-tions of the division
body 61 1 in the longitudinal direction, plate-shaped slider bodies 616 which are
disposed inside the concave pol-tions 613, elastic bodies 617 which biases the slider
bodies 616 so as to be pushed out from the concave portions 613, and stoppers 514
which are provided on the inner surfaces of the concave portions 613.
[0131]
The slide body 616 is biased toward the stopper 5 14 side by the elastic body
617. In addition, the slide body 616 moves inside the concave portion 613 within a
range limited by the elastic body 617 in a state where end surfaces 61 6a of the slide
body 616 come into contact with the inner surfaces of the concave portion 613.
[0132]
One end of the elastic body 617 is connected to the slide body 616, and the
other end thereof is connected to a bottom surface 613a of the concave portion 613
For example, the elastic body 617 is a coil spring or aplate spring. In addition, the
engagement portion 522 of thc connection body 520 which is inserted into the concave
portion 613 is disposed between the slide body 61 6 and the stopper 5 14.
[0133]
In addition, as shown in FIG. 52, each of the division bodies 61 I of the mandrel
610 may further include a receiving portion 618 which is provided on the slide body
616 and has a receiving surface 618a which comes into contact with the engagement
portion 522 of the connection body 520. In this case, since the engagement portion
522 of the connection body 520 is held by the receiving portion 61 8 of the slide body
61 6, a smooth movement of the engagement portion 522 of the connection body 520 is
realized.
[0134]
In addition, as shown in FIG. 53, the shape of the slide body 616 of the mandrel
610 may be a U shape, and for example, two stoppers 514 may be provided in the
concave portion 613. In this case, a smooth movement of the slide body 616 can be
realized.
[0135]
Next, the movement of the mandrel 610 will be described. In a state where
compressive stress is not applied to portions between the adjacent division bodies 6 11
(refer to FIG. 50), as shown in FIG. 51, the length of the elastic body 617 is an initial
length. Accordingly, the engagement portion 522 of the connection body 520 is
positioned so as to be close to the stopper 514. Since the engagement portion 522 of
the connection body 520 is positioned so as to be close to the stopper 514, a range in
which the connection body 520 can be inclined is relatively wide. Accordingly, the
relative position of the adjacent division bodies 61 1 connected by the connectioii body
520 can be changed in an upward-downward direction.
[0136]
If the upper press tool 220 is lowered from the state shown in FIG. 50 and the
intermediate press-formed product 25 1 is pressed by the upper press tool 220,
compressive stress which allows the adjacent division bodies 611 to approach each
other is applied to the mandrel 61 0. At this time, the slide body 61 6 is pressed toward
the bottom surface 613a of the concave portion 613 by the engagement poltion 522 of
each of the connection bodies 520, and the elastic body 617 is compressed. Since the
elastic body 617 is compressed, the main body portion 521 of the connection body 520
enters the concave portion 613. Accordingly, the adjacent division bodies 61 1
approach each other.
101371
According to the above-described operation, the adjacent division bodies 61 1
approach each other via the connection body 520, the division bodies 61 1 are adjacent
to each other with a predetermined gap or come into contact with each other. In
addition, the plurality of division bodies 61 1 are arranged in a line. Accordingly, by
lowering the upper press tool 220, the entire length of the mandrel 61 0 decreases.
[0138]
Next, the operation of the mandrel 610 when the intermediate press-formed
product 251 is press-formed using the manufacturing device 600 will be described with
reference to FIGS. 54 to 56. FIGS. 54 to 56 are front schematic views showing the
division bodies 611 of the mandrel 610 and the connection bodies 520 which connect
the division bodies 611 adjacent to each other.
[0139]
As shown in FIG. 54, in a state before the upper press tool 220 of the
manufacturing device 600 is lowered, in the mandrel 610, the central division body
611X is positioned at a higher position than other division bodies 611 in accordance
with the shape of the web portion 252 of the intermediate press-formed product 251.
The heights of other division' bodies 61 1 decrease as the division bodies 61 1 are
separated from the division body 61 1X.
[0140]
In the state shown in FIG. 54, compressive stress is not applied to the mandrel
610. Accordingly, the elastic body 617 of each of the division bodies 61 1 is not
compressed, and the division bodies 611 adjacent each other are separated from each
other with a relatively wide gap.
[0141]
If the upper press tool 220 of the manufacturing device 600 is lowered and the
intermediate press-formed product 251 is pressed by the upper press tool 220, the
heights of the division bodies 61 1 approach the same height as each other in accordance
with the distortion of the web portion 252 of the intermediate press-foimed product 251
In addition, the division bodies 61 1 which are positioned on both ends of the mandrel
610 are restricted by the pair of shoi-t-side walls 13 which restricts both ends of the
intermediate press-formed product 25 1 in the longitudinal direction. If the uppcr press
tool 220 further lowers and the bending portion 2521, of the web portion 252 of the
intermediate press-formed product 251 extends, the heights of the division bodies 61 1
are ille same as each other. Simultaneously, compressive stress is applied to the
mandrel 610, the elastic body 617 is compressed so as to be constricted, and the gap
between the division bodies 61 1 decreases.
[0142]
The reason why the conlpressive stress is applied to the mandrel 6 10 is as
follows. That is, while the entire length ofthe intermediate press-formed product 25 1
is L1 in the state before the upper press tool 220 is lowered, in the state after the upper
press tool 220 is lowered, the entire length of the intermediate press-formed product 251
is compressed so as to be L by the upper press tool 220 and the pair of shoi-t-side walls
13. As a result, since compressive stress is also applied to the mandrel 610 disposed
along the web portion 252 of the intermediate press-formed product 251 by the upper
press tool 220 and the pair of short-side walls 13, the compressive stress is applied to
the mandrel 6 10.
[0143]
FIG. 55 shows an example of the mandrel 610 in a state where the upper press
tool 220 is lowered to the bottom dead center. In the mandrel 610 shown in FIG. 55,
the gaps between the division bodies 611 are the same as each other. In this way, in
order to allow the gaps between the division bodies 611 to be constant, a spring constant
of the elastic body 617, the length of the connection body 520, the depth of the concave
portion 613, or the like may be adjusted.
[0144]
In addition, FIG. 56 shows another example of the mandrel 610 in a state where
the upper press tool 220 is lowered to the bottom dead center. In the mandrel 610
shown in FIG. 56, the gaps between some division bodies 61 1 are narrower than the
gaps between other division bodies 61 1. Specifically, the gaps between the central
division body 61 1X and two division bodies 611 adjacent to the central division body
611X relatively decrease, and the gaps between other division bodies 61 1 relatively
increase. The central division body 61 1X and two division bodies 611 adjacent to the
central division body 611X are positioned in the vicinity of the bending portion 252b of
the web portion 252 of the intermediate press-formed product 251. In this way, in the
mandrel 610 shown in FIG. 56, the division bodies 611, which are positioned in the
vicinity of the bending portion 252b in which buckle easily occurs, approach each other
in the state where the upper press tool 220 is lowered to the bottom dead center.
101451
In order to allow the gaps between the division bodies 61 1 to be different from
each other, the spring constant of the elastic body 617, the length of the connection body
520, the depth of the concave portion 613, or the like may be adjusted. In the mandrel
610 shown in FIG. 56, for example, spring constants of the elastic bodies 617 of the
central division bodies 611X and the two division bodies 611 adjacent to the central
division bodies 611X may be smaller than the spring constants of other elastic bodies
617. In addition, the entire length of each of the connection bodies 520 which
connects the central division body 61 1X and two division bodies 61 1 adjacent to the
central division body 61 1X may be shorter than the entire length of each of other
connection bodies 520. Moreover, the depth of each of the concave portions 613 of the
central division body 611X and two division bodies 61 1 adjacent to the central division
body 61 1X may be shallower than the depth of each of other concave portions 613.
[0 1461
According to the present embodiment, the mandrel 610 in which the entire
length can increase and decrease is used, the mandrel 610 is inserted along the web
portion 252 of the intermediate press-formed product 251, and the intermediate
press-formed product 25 1 is press-formed while the entire length of the mandrel 61 0
decreases. Accordingly, it is possible to restrict the entire intermediate press-formed
product 251 by the mandrel 610, and it is possible to reliably prevent the buckling
distortion of the web portion 252 and the vertical wall portions 253.
[0147]
[Modification Example of Mandrel 6101
FIGS. 57 and 58 are views showing a modification example of the mandrel 610.
As shown in FIGS. 57 and 58, instead of the slide body 616, the elastic body 617, and
the connection body 520, a connection body 620 may be provided in the division body
611 of the mandrel 610.
[0148]
A main body portion 621 of the connection body 620 shown in FIGS. 57 and
58 is configured of two division main body portions 621a and 621b. The division
main body portions 621a and 621b are configured by dividing the main body portion
621 into two portions at the center in the longitudinal direction.
[0 1491
One end of each of the division main body portions 621a and 621b in the
longitudinal direction is connected to the engagement portion 522, and each of the
division main body portions 621a and 621b includes a notch portion 621c and a
protrusion portion 621d which is provided on the other end. The notch portion 621c
and the protrusion portion 621d are configured so as to be fitted to each other. In
addition, ihe elastic body 617 is provided on ihe distal end of the protrusion portion
621d of the division main body portion 621a, and a slide pin 621e is provided on the
distal end of the protrusion portion 621d of the division main body portion 621b. The
elastic body 617 is connected to the notch portion 621c of the division main body
portion 621b. Moreover, the slide pin 621e is inserted into an insertion hole (not
shown) which is provided in the notch portion 621c of the division main body portion
621a. Since the elastic body 617 is disposed between the division main body portions
621a and 621b, the division main body portions 621a and 621b are separated from each
other.
[0150]
According to this configuration, in the mandrel 610 shown in FIGS. 57 and 58,
when compressive stress is applied to the mandrel 61 0 along the longitudinal direction,
the elastic body 617 is compressed, the gap between the division main body portions
621a and 621b decreases, and it is possible to decrease the entire length of the
connection body 620. Accordingly, similarly the present embodiment, it is possible to
increase and decrease the entire length of the mandrel 610.
[0151]
In addition, instead of the connection body 620, a connection body 625 shown
in FIG. 59 may be used. FIG. 59 is a plan view showing the connection body 625.
The connection body 625 is configured by dividing the connection body 525 shown in
FIG. 48.
[0152]
A plate-shaped main body portion 626 of the connection body 625 shown in
FIG. 59 is configured of two division main body portions 627 and 628. The division
main body portions 627 and 628 are configured by dividing the main body portion 626
into two at approximately the center in the longitudinal direction.
101531
Aprotrusion portion 627a is provided at the center of one division main body
portion 627 in the width direction. In addition, a notch portion 628a is provided at the
center of the other division main body portion 628 in the width direction. Moreover,
the elastic body 617 is provided on the distal end of the protrusion portion 627a. The
elastic body 617 is connected to the notch portion 628a of the division main body
portion 628. In addition, slide pins 629 are provided on the end surface 627b on both
sides of the protrusion portion 627a of the division main body portion 627 in the width
direction. Each of the slide pins 629 is inserted into an insertion hole (not shown)
which is provided an end surface 628b of the division main body po~tion6 28. Since
the elastic body 617 is disposed between the division main body portions 627 and 628,
the division main body portions 627 and 628 are separated from each other.
[0154]
According to this configuration, similarly to the connection body 620, the
entire length of the connection body 625 can increase and decrease.
[0155]
(Seventh Embodiment)
Next, a seventh embodiment of the present invention will be described.
[0156]
FIGS. 61 and 62 are front views showing a device 700 for manufacturing a
press-formed product (hereinafter, simply referred to as a manufacturing device 700)
according to the seventh embodiment. The manufacturing device 700 according to the
present embodiment is configured ofthe manufacturing device 1 according to the first
embodiment, and the mandrel 610 according to the sixth embodiment.
[0157]
In the present embodiment, an intermediate press-formed product 761 shown in
FIGS. 60A to 60C are press-formed using the manufacturing device 700. As shown in
FIGS. 60A to 60C, the intermediate press-formed product 761 includes a web portion
762 and a pair of vertical wall portions 763. In addition, the intermediate press-formed
product 761 is different from the intermediate press-formed product 251 (refer to FIGS.
24A and 24B) in that three bending portions 252b and four linear portions 252a are
provided.
[0158]
FIG. 63 is a view showing a state where the intermediate press-formed product
761 is press-formed using the manufacturing device 700. In the present embodiment,
similarly to the sixth embodiment, since the mandrel 610 is changed in accordance with
the shape of the intermediate press-foimed product 761, it is possible to prevent
buckling distortion of the intermediate press-formed product 761.
[0159]
In addition, in the manufacturing device 700, an intermediate press-formed
product 771 shown in FIGS. 64A to 64C may be used. As shown in FIGS. 64A to 64C,
the intermediate press-formed product 771 includes a web portion 772 and a pair of
vertical wall portions 773. In addition, the intermcdiate press-formed product 771 is
different from the intermediate press-formed product 251 (refer to FIGS. 24A and 24B)
in that four bending pol-tions 252b and five linear portions 252a are provided. When
the intermediate press-formed product 771 is press-fornled by the manufacturing device
700, as shown in FIG. 65, the intermediate press-formed product 771 may be disposed
in the manufacturing device 700.
[0160]
In addition, in the manufacturing device 700, an intermediate press-formed
product 781 shown in FIGS. 66A to 66C may be used. As shown in FIGS. 66A to 66C,
the intermediate press-formed product 781 includes a web portion 782 and a pair of
vertical wall portions 783. The intermediate press-formed product 781 is different
from the intermediate press-formed product 35 1 (refer to FIGS. 33A to 33C) in that two
bending portions 252b, six linear portions 252a, and three bending portions 352c are
provided. When the intermediate press-formed product 781 is press-formed by the
manufacturing device 700, as shown in FIG 67, the intermediate press-formed product
781 may be disposed in the manufacturing device 700. In this case, preferably, the
shaft portions 5 15 are provided on the division bodies 61 1 of the mandrel 610 which
comes into contact with the bending portions 252b of the intermediate press-formed
product 781.
[0161]
In addition, in the manufacturing device 700, an intermediate press-fotmed
product 791 shown in FIGS. 68A to 68C may be used. As shown in FIGS. 68A to 68C,
the intermediate press-formed product 791 includes a web portion 792, a pair of vertical
wall portions 793, and flanged portions 794. The intermediate press-formed product
791 is different from the intermediate press-formed product 761 (refer to FIGS. 60A to
60C) in that the flanged portions 794 are provided. When the intermediate
press-formed product 791 is press-formed by the manufacturing device 700, as shown in
FIG. 69, the intermediate press-formed product 791 may be disposed in the
manufacturing device 700.
[0162]
(Eighth Embodiment)
Next, an eighth embodiment of the present invention will be described.
[0163]
FIG. 70 is a perspective view showing a device 800 for manufacturing a
press-formed product (hereinafter, simply referred to as a manufacturing device 800)
according to the eighth embodiment. In the first embodiment, the pair of short-side
walls 13 of the manufacturing device 1 are fixed to the base portion 11 (refer to FIG. 2)
Meanwhile, in the manufacturing device 800 according to the present embodiment, the
intermediate press-formed product 51 is press-fonned while a short-side wall 814
(pressurization restriction wall) which is provided on the base portion 11 approach a
short-side wall 813 (pressurization restriction wall) according to lowering of an upper
press tool 820.
[O 1641
FIG. 71A is a front view showing the manufacturing device 800, and is a view
showing a state before the upper press tool 820 is lowered. As shown in FIG. 71A, a
lower press tool 8 10 includes the base portion 11, the short-side wall 8 13 (fixing
restriction wall) which is fixed to the upper surface 1 la of the base portion 11, the
short-side wall 814 (pressurization restriction wall) which is provided on the upper
surface 1 la of the base portion 11 and moves on the base portion 11, a cam slider 81 5
which is coupled to the short-side wall 8 14, a support portion 8 16 which is fixed to the
base portion 11, a slide pin 81 7 which is connected to the cam slider 8 15 through the
support portion 816, and a return spring 818 which connects the support portion 816 and
the slide pin 8 17. An inclined slide surface 81 5a is provided on the cam slider 8 15.
In addition, the slide pin 817 is biased toward a direction, which is separated from the
short-side wall 814, by the return spring 818. The slide pin 817 can be inserted into
and extracted from the support portion 816 along the longitudinal direction. In
addition, the cam slider 8 15 which is fixed to the slide pin 81 7 slides along the
longitudinal direction of the slide pin 817.
[0165]
A concave portion 813% a plate-shaped workpiece receiving portion 813b, a
hinge 813c, and a spring member 813d (elastic body) are provided on the surface of the
short-side wall 813 facing the short-side wall 814. The workpiece receiving portion
813b is connected to the short-side wall 813 via the hinge 813c. Accordingly, the
workpiece receiving portion 813b is movable with respect to the short-side wall 813
with the hinge 813c as an axis.
[0166]
The workpiece receiving portion 8 13b is accommodated in the concave portion
8 13a in a case where the workpiece receiving portion 813b is closest to the short-side
wall 8 13. In addition, a spring member 8 13d is disposed between the workpiece
receiving portion 813b and the short-side wall 8 13. The spring member 8 13d biases
the workpiece receiving portion 813b toward the short-side wall 814.
[0 1 671
Similarly, a concave portion 814a, a plate-shaped workpiece receiving portion
814b, a hinge 814c, and a spring member 814d (elastic body) are provided on the
surface ofthe short-side wall 814 facing the short-side wall 813. The workpiece
receiving portion 814b is connected to the short-side wall 814 via the hinge 814c.
Accordingly, the workpiece receiving portion 8 14b is movable with respect to the
short-side wall 814 with the hinge 814c as an axis.
[0168]
The workpiecc receiving portion 814b is accon~modatedin the concave portion
814a in a case where the workpiece receiving portion 814b is closest to the short-side
wall 814. In addition, a spring member 814d is disposed between the workpiece
receiving portion 814b and the short-side wall 814. The spring member 814d biases
the workpiecc receiving portion 8 14b toward the short-side wall 8 13.
[O 1691
The upper press tool 820 is configured of the main body poi-tion 21, the punch
portion 22, the convex portion 23, and a cam driver 825 which is attached to the punch
portion 22. An inclined slide surface 825a is provided on the cam driver 825.
[0170]
In addition, when the cam driver 825 of the upper press tool 820 is lowered
toward the cam slider 8 15 of the lower press tool 810, the cam slider 8 15 and the cam
driver 825 are positioned such that the inclined surface 81 5a of the cam slider 8 15 and
the inclined surface 825a of the cam driver 825 come into contact with each other.
[0171]
Hereinafter, a method for manufacturing a press-formed product of the present
embodiment will be described. First, as shown in FIG. 71A, the intermediate
press-formed product 51 is disposed between the upper press tool 820 and the lower
press tool 810. At this time, the intermediate press-formed product 51 is disposed such
that the convex side (extension surface) of the bending portion 52b of the intermediate
press-formed product 51 faces the upper press tool 820. In addition, both ends of the
intermediate press-fonned product 5 1 in the longitudinal direction come into contact
with the workpiece receiving portions 8 13 b and 8 14b. The workpiece receiving
portions 81 3b and 814b are pressed by both ends of the intermediate press-formed
product 5 1 in the longitudinal direction by the spring members 8 13d and 8 14d. In this
way, both ends of the intermediate press-formed product 51 in the longitudinal direction
are restricted by the short-side walls 813 and 814.
[0172]
FIG. 71B is a view showing a state where the upper press tool 820 is lowered.
As shown in FIG. 71B, the cam driver 825 comes into contact with the cam slider 81 5
according to the lowering of the upper press tool 820. In addition, according to the
lowering of the cain driver 825, the cain slider 815 slides toward the short-side wall 813
against a spring force of the return spring 818. According to the sliding of the cam
slider 815, the short-side wall 814 slides toward the short-side wall 813.
[0 1731
If thc upper press tool 820 is fui-ther lowered, the short-side wall 814 slides, the
convex portion 23 of the upper press tool 820 comes into contact with the web portion
52 of the intermediate press-formed product 51, and the intermediate press-formed
product 51 is compressed in the longitudinal direction. 111 the present embodiment,
since the short-side wall 814 slides toward the short-side wall 813, the distance between
the short-sidc walls 813 and 814 decreases according to the lowering of the upper press
tool 820. Accordingly, it is possible to increase a compressive force in the longitudinal
direction which is applied to the intermediate press-folmed product 51.
[O 1741
In addition, as shown in FIG. 71C, the press forming ends when the upper press
tool 820 reaches the bottom dead center.
[0 1751
Here, if attention is focused on both ends of the intermediate press-formed
product 5 1 in the longitudinal direction, in a state before the press forming starts, as
shown in FIGS. 71A and 71B, both ends of the intermediate press-formed product 51 in
the longitudinal direction are inclined with respect to the upper surface 1 la of the base
portion 11. However, according to proceeding of the press forming, the inclination
angles of both ends of the intermediate press-formed product 5 1 in the longitudinal
direction becomes perpendicular with respect to the upper surface 1 la of the base
portion 11.
[0 1761
In this way, according to proceeding of the press fom~ingt,h e inclination angles
of both ends of the intermediate press-formed product 51 in the longitudinal direction
are changed. With respect to both ends of the intermediate press-formed product 51 in
the longitudinal direction, the plate-shaped workpiece receiving portions 813b and 814b
always press both ends of the intermediate press-formed product 51 in the longitudinal
direction by the spring members 813d and 814d. In this way, in the present
embodiment, the state where both ends of the intermediate press-formed product 51 in
the longitudinal direction are restricted by the workpiece receiving portions 813b and
8 14b is maintained.
[0177]
According to the present embodiment, since the intermediate press-formed
product 51 is press-formed such that the cui-vature of the bending portion 52b of the
intermediate press-formed product 51 decreases while the distance between the
short-side wall 813 and the short-side wall 814 decreases, it is possible to reliably apply
the compressive stress to the intermediate press-formed product 5 1 along the
longitudinal direction.
In addition, since the upper press tool 820 is lowered in the state where the
workpiece receiving portions 813b and 814b come into contact with both ends of the
intermediate press-formed product 51 in the longitudinal direction, it is possible to
equally apply a load to both ends of the intermediate press-formed product 51 in the
longitudinal direction, and it is possible to apply compressivc stress to both ends of the
intermediate press-formed product 5 1 without buckling both ends of the intermediate
press-formed product 5 1.
In addition, since an axial compressive force is easily released to extract the
press-formed product when the press tool is removed, it is possible to prevent the
formed product from protruding due to elastic recovery of the press-formed product.
[0178]
In addition, in the manufacturing device 800, an intermediate press-formed
product 861 shown in FIGS. 72A to 72C may be used. The intermediate press-formed
product 861 includes a web portion 862 and a pair of vertical wall portions 863.
Moreover, the intermediate press-formed product 861 is different from the intermediate
press-formed product 451 (refer to FIGS. 39A to 39C) in that short sides 863a and 863b
of the vertical wall portions 863 are not parallel with each other. As shown in FIG
73Aand 73B, by disposing the intermediate press-formed product 861 in the
manufacturing device 800 and lowering the upper press tool 820, it is possible to
compress the intermediate press-formed product 861 in the longitudinal direction.
[0179]
Moreover, in the manufacturing device 800, an intermediate press-formed
product 871 shown in FIGS. 74A to 74C may be used. The intermediate press-formed
product 871 includes a web portion 872 and a pair of vertical wall portions 873.
Moreover, the intermediate press-formed product 871 is different fiom the intermediate
press-foimed product 761 (refer to FIGS. 60A to 6OC) in that short sides 873a and 873b
of the vertical wall portions 873 are not parallel with each other. As shown in FIG.
75A and 75B, by disposing the intermediate press-formed product 871 in the
manufacturing device 800 and lowering the upper press tool 820, it is possible to
compress the intermediate press-formed product 871 in the longitudinal direction. In
addition, in this case, preferably, the blank holder pad 331 (refer to FIGS. 32A to 32C)
is disposed between the pair of vertical wall portions 873 ofthe intermediate
press-formed product 871.
[0180]
Moreover, in the manufacturing device 800, an intermediate press-formed
product 881 shown in FIG. 76 may be used. As shown in FIG. 76, the intermediate
press-formed product 881 is different from the intermediate press-formed product 251
(refer to FIGS. 24A and 24B) in that semicircular flanged portions 884 are providcd on
both ends in the longitudinal direction. In addition, the pair of flanged poi-tions 884 is
not parallel with each other. As shown in FIG. 77, by disposing the intermediate
press-formed product 881 in the manufacturing device 800 such that the flanged
poi-tions 884 of the intermediate press-formed product 881 come into contact with the
workpiece receiving portions 813a and 814b and lowering the upper press tool 820, it is
possible to compress the intermediate press-formed product 881 in the longitndinal
direction.
[0181]
Moreover, in the manufacturing device 800, an intermediate press-formed
product 886 shown in FIG. 78 may be used. The intermediate press-formed product
886 is different from the intermediate press-formed product 881 (refer to FIG. 76) in
that three quadrilateral flanged portions 887 are provided on each of both ends in the
longitudinal direction.
[0 1821
In addition, in the manufacturing device 800, an intermediate press-formed
product 888 shown in FIG. 79 may be used. The intermediate press-formed product
888 is different from the intermediate press-formed product 881 (refer to FIG. 76) in
that flanged portions 889 are provided on ends of the vertical wall portions 253 in the
width direction.
[0183]
Moreover, as shown in FIGS. 80A and SOB, in the manufacturing device 800,
the intermediate press-formed product 251 (refer to FIGS. 24A and 24B) can be used.
In this case, since both ends of the intermediate press-formed product 251 in the
longitudinal direction are parallel with each other, the workpiece receiving portions
813b and 814b, the concave portions 8 13a and 814a, and the spring members 813d and
814d may not be provided in the lower press tool 810.
[0184]
(Ninth Embodiment)
Next, a ninth embodiment of the present invention will be described.
[0185]
FIG. 81 is a schematic view showing a device 900 for manufacturing a
press-formed product (hereinafter, referred to as a manufacturing device 900) according
to the ninth embodiment. As shown in FIG. 81, the manufacturing device 900 is
different from the manufacturing device 800 according to the eighth embodiment in that
the punch portion 222 (refer to FIG. 25A) having the concave portion 223 and the
mandrel 61 0 (refer to FIG. 50) are provided.
[0186]
The manufacturing device 900 is used when an intermediate press-formed
product 951 is press-formed. Here, the intermediate press-formed product 951 has the
same configuration as that of the intermediate press-formed product 251 (refer to FIG.
24A) except that both ends in the longitudinal direction are not parallel with each other.
[0187]
FIGS. 82A to 82C are longitudinal sectional views showing the manufacturing
device 900. In addition, FIG. 82B is a view showing a middle state where an upper
press tool 920 lowers, and FIG. 82C is a view showing a state where the upper press tool
920 is lowered to the bottom dead center. First, as shown in FIG. 82A, the
intermediate press-formed product 951 is disposed in the manufacturing device 900
such that both ends of the intermediate press-formed product 951 in the longitudinal
direction come into contact with the working receiving portions 8 13b and 8 14b. At
this time, the mandrel 610 is inserted into a space which is surrounded by a web poi-tion
952 and a pair of vertical wall portions 953 of the intermediate press-formed product
951.
[0188]
Subsequently, as shown in FIGS. 82B and 82C, the upper press tool 920 is
lowered, and the intermediate press-formed product 951 is press-formed. At this time,
the web portion 952 and the pair of vertical wall portions 953 of the intermediate
press-formed product 95 1 are held by the concave portion 223 of the upper press tool
920 and the mandrel 610. Accordingly, it is possible to prevent buckling distortion
when the intermediate press-formed product 95 1 is compressed in the longitudinal
direction.
[0189]
As described above, in the present embodiment, the intermediate press-formed
product 95 1 is held by the mandrel 610 and the concave portion 223 of the upper press
tool 920, and the intermediate press-formed product 951 is conlpressed in the
longitudinal direction. Accordingly, with respect to the nlanufacturing device 800 of
the eighth embodiment, it is possible to reliably prevent buckling distortion of the
intermediate press-forn~edp roduct 95 1.
[0190]
Hereinbefore, embodiments of the present invention are described. However,
the embodiments are exemplified, and the scope of the present invention is not limited
to the embodiments. The embodiments can be modified to various aspects, and
various omissions, replacements, modifications can be applied within a scope which
does not depart from the gist of the present invention. If the embodiments or the
modifications are included in the scope or gist of the present invention, the
embodiments or the modifications are included in a range equivalent to the invention
disclosed in the claims.
[0191]
For example, in the embodiments the cases where the intermediate
press-formed product is formed by one-time stroke (the number of times of the lowering
of the upper press tool is one) are shown. However, the intermediate press-formed
product may be formed by a plurality of strokes (the number of times of the lowering of
the upper press tool is multiple). That is, as shown in FIGS. 83A to 83C, a curvature
m, of the intermediate press-formed product 51 may be brought into mk by a first stroke,
and the curvature mk of the intermediate press-formed product 5 1 may be brought into
m, by a second stroke.
[0192]
In addition, for example, in the embodiments, the cases where the intermediate
press-formed product includes the bending portion foimed by plastic deformation are
shown. However, instead of the intermediate press-formed product, a steel having a
bending portion (that is, a bending portion which is formed by elastic deformation)
which is formed by the own weight of the intermediate press-formed product may be
used.
101931
Moreover, for example, in the eighth embodiment, the case is shown, in which
the cam driver 825 of the upper press tool 820 comes into contact with the cam slider
815 of the lower press tool 810, and thus, the short-side wall 814 approaches the
short-side wall 13. However, a separate slide mechanism may be provided on the
lower press tool 810 so as to independently control the upper press tool 820 and the
lower press tool 8 10.
[O 1941
In addition, for example, the direction of the bending or a bending amount of
the bending in the intermediate press-formed product may be appropriately adjusted as
long as the intermediate press-formed product is bent toward the thickness direction of
the web portion. In addition, the intermediate press-formed product may be bent in an
arc shape, or may be bent in an elliptical arc shape.
[Industrial Applicability]
[0195]
According to the present invention, it is possible lo provide a method for
manufacturing the press-formed product, the device for lnanufacturiug the press-formed
product, the mandrel, and the press-formed product capable of simultaneously achieving
a decrease in weight and high rigidity without the need of welding.
[Brief Description of the Reference Symbols]
[O 1961
1: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT (FIRST
EMBODIMENT)
10: LOWER PRESS TOOL (FIRST PRESS TOOL)
11 : BASE PORTION
12: LONG-SIDE WALL
13: SHORT-SIDE WALL (RESTRICTION WALL)
14: GROOVE PORTION
20: UPPER PRESS TOOL (SECOND PRESS TOOL)
21: MAW BODY PORTION
22: PUNCH PORTION
23: CONVEX PORTION
5 1 : INTERMEDIATE PRESS-FORMED PRODUCT
52: WEB PORTION
52.4: LINEAR PORTION OF WEB PORTION
52B: BENDING PORTION OF WEB PORTION
53: VERTICAL WALL PORTION
53a, 53b: SHORT SIDE OF VERTICAL WALL PORTION
200: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(SECOND EMBODIMENT)
210: LOWER PRESS TOOL
214: CONVEX PORTION OF BASE PORTION
220: UPPER PRESS TOOL
222: PUNCH PORTION
223: CONCAVE PORTION
25 1 : INTERMEDIATE PRESS-FORMED PRODUCT
252: WEB PORTION
252a: LlNEAR PORTION OF WEB PORTION
252b: BENDING PORTION OF WEB PORTION
253: VERTICAL WALL PORTION
253a, 253 b: SHORT SIDE OF VERTICAL WALL PORTION
300: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(THIRD EMBODIMENT)
33 1 : BLANK HOLDER PAD (BLANK HOLDER TOOL)
400: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(FOURTH EMBODIMENT)
500: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(FIFTH EMBODIMENT)
510: MANDREL
5 11 : DIVISION BODY
520: CONNECTION BODY
600: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(SIXTH EMBODIMENT)
610: MANDREL
61 1: DIVISION BODY
6 13 : CONCAVE PORTION
616: SLIDE BODY
617: ELASTIC BODY
700: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(SEVENTH EMBODIMENT)
800: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(EIGHTH EMBODIMENT)
810: LOWER PRESS TOOL
813: SHORT-SIDE WALL (FIXING RESTRICTION WALL)
814: SHORT-SIDE WALL (PRESSURIZATION RESTRICTION WALL)
815: CAM SLIDER
8 16: SUPPORT PORTION
8 17: SLIDE PIN
81 8: RETURN SPRING
820: UPPER PRESS TOOL
825: CAM DRIVER
900: DEVICE FOR MANUFACTURING PRESS-FORMED PRODUCT
(NINTH EMBODIMENT)
920: UI'PER PRESS TOOL
[Document Type] CLAIMS
1. A method for manufacturing a press-formed product, comprising:
a first step of preparing a long material having a bending portion; and
a second step of decreasing curvature of the bending portion while restricting
both ends of the long material in a longitudinal direction.
2. The method for manufacturing a press-formed product according to claim 1,
wherein in the second step, the curvature decreases while the shortest distance
between both ends of the long material is constantly maintained.
3. The method for manufacturing a press-formed product according to claim 1,
wherein in the second step, the curvature decreases while the shortest distance
between both ends of the long material decreases.
4. The method for manufacturing a press-formed product according to any one of
claims 1 to 3,
wherein in the second step, the curvature decreases while at least a concave
side of the bending portion of the long material is supported.
5. The method for manufacturing a press-formed product according to any one of
claims 1 to 4,
wherein in the second step, the curvature decreases in stages.
6. The method for manufacturing a press-formed product according to any one of
claims 1 to 5,
wherein planes including edges of both ends of the long material are parallel
with each other.
7. A device for manufacturing a press-fonned product using a long material having a
bending portion, comprising:
a first press tool which includes a base portion, and a pair of restriction walls
which is provided on the base poi-tion, comes into contact with both ends ofthe long
material in a longitudinal direction, and faces each other; and
a second press tool which includes a punch portion which presses a convex side
of the bending portion of the long material inserted between the pair of restriction walls,
wherein a distance between the pair of restriction walls is shorter than the
entire length when the long material linearly extends.
8. The device for manufacturing a press-formed product according to claim 7,
wherein the distance between the pair of restriction walls is the same as the
shortest distance between both ends of the long material in the longitudinal direction.
9. The device for manufacturing a press-formed product according to claim 7 or 8,
wherein each of the pair of restriction walls includes a curve shaped guide
surface which comes into contact with the end portion of the long material in the
longitudinal direction when the long material is inserted between the restriction walls.
10. The device for manufacturing a press-formed product according to any one of
claims 7 to 9, further comprising:
a blank holder tool which is disposed between the pair of restriction walls, and
includes a support surface which comes into contact with at least a concave side of the
bending portion of the long material.
11. The device for manufacturing a press-formed product according to claim 7,
wherein one of the pair of restriction walls is a fixing restriction wall which is
fixed to the base portion, and
the other of the pair of restriction walls is a pressurization restriction wall
which approaches the fixing restriction wall when the punch portion moves while
coming into contact with the convex side of the bending portion of the long material.
12. The device for manufacturing a press-formed product according to claim 11,
wherein at least one of the fixing restriction wall and the pressurization
restriction wall includes:
a workpiece receiving portion which comes into contact with one end of the
long material; and
an elastic body which biases the workpiece receiving portion toward the one
end of the long material.
13. The device for manufacturing a press-formed product according to claim 11 or 12,
further comprising:
a blank holder tool which is disposed between the fixing restriction wall and
the pressurization restriction wall, and includes a support surface which comes into
contact with at least a concave side of the bending portioil of the long material.
14. A mandrel which is used in the device for manufacturing a press-formed product
according to any one of claims 7 to 13, comprising:
a plurality of division bodies which support the concave side of the long
material; and
a connection body which connects the division bodies,
wherein a line shape of the division bodies is changed according to the shape of
the bending portion of the long material.
15. A mandrel according to claim 14,
wherein each division body includes:
a concave portion which accoinmodates the connection body when the division
bodies are arranged in a line; and
an elastic body which is provided between a bottom surface of the concave
portion and an end portion of the connection body inserted into the concave portion.
16. The mandrel according to claim 14,
wherein the connection body includes:
a pair of division connection bodies which is movable close to and away from
each other within a predetermined range; and
an elastic body which is provided between the pair of division connection
bodies and biases the pair of division connection bodies in a direction separated from
each other.
17. A press-formed product which is long in one direction, comprising:
a high cross-sectional area portion which has the largest cross-sectional area
when viewed in a cross section perpendicular to a longitudinal direction;
a low cross-sectional area poi-tion which has a cross-sectional area which is
smaller than that of the high cross-sectional area portion; and
an intermediate portion which is provided between the high cross-sectional
area portion and the low cross-sectional area portion, and in which a cross-sectional area
continuously changes along the longitudiilal direction.
18. The press-formed product according to claim 17,
wherein a plurality of high cross-sectional area portions are provided in a
plurality of locatioils along the lollgitudi~ladl irection.