Technical Field
[0001]
The present invention relates to an end structure of a vehicle to prevent an
object from becoming wedged under a vehicle when the vehicle collides with the
10 object.
Background Art
[0002]
For example, in the event of head-on collision or rear end collision of a
15 passenger vehicle and a large vehicle such as a truck, due to a difference in
installation heights of strength members such as cross members provided in the
vehicles, the passenger vehicle may become wedged under the large vehicle.
Therefore, in the related art, an underrun protector is provided at the front part and
the rear part of the large vehicle in accordance with an installation height of a
20 strength member of the passenger vehicle. The undetTun protector is an exampfe of
an end structure of a vehicle. In addition, underrun protectors include a fi"ont
underrun protector (FUP) provided at the front of a vehicle and a rear underrun
protector (RUP) provided at the rear of a vehicle.
[0003]
25 It is necessary for such an undenun protector to prevent the passenger
. .
.. ,, ' .. 'vehicle fh)m becoming wedged under the large" vehiCle and to" 'exhibit a collision
energy absmption effect due to a cmshable zone provided at the fi:ont or rear part of
the passenger vehicle. Therefore, there is a higher demand for the underrun
protector to have load resistance performance to generate a reaction force by which
30 the passenger vehicle that collides with the large vehicle is cast aside rather than for
an effect of absorbing the collision energy generated when collision with the
PCT/JP2016/052924
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passenger vehicle occurs.
[0004]
For example, techniques related to underrun protectors are disclosed in
Patent Literature 1 to 3. Such underrun protectors have a structure in which a beam
5 that extends in a vehicle width direction is fastened to a vehicle body frame with a
bracket or a stay (support) therebetween.
[0005]
In addition, in the underrun protector disclosed in Patent Literature 4, a
reinforcing member is provided to bridge a frame attaclm1ent part attached to a
10 vehicle body frame and a beam attachment surface (a main body attachment part)
attached to a beam in a plan view. Thus, improvement of the load resistance
performance is attempted.
Citation List
15 Patent Literature
20
25
[0006]
Patent Literature 1:
Patent Literature 2:
Patent Literature 3:
Patent Literature 4:
Technical Problem
[0007]
JP 2005-88740A
JP 2005-225325A
JP 2005-225326A
JP 2004-243984A
Summary oflnvention
As a method of evaluating load resistance performance, there is a method in
whiCh, at an attachment position of a beam· in a stay or at a position lateral to the
attachment position in a vehicle width direction, when a load is applied to a collision
surface (a surface with which another vehicle collides) of the beam, a maximum load
that can be input is evaluated. The performance of an underrun protector as a
30 product depends on the superiority or inferiority of the load resistance performance.
Therefore, the development of an underrun protector in which a maximum input load
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at any collision position in a load resistance performance evaluation test is greater
than in the related mt is desirable.
[0008]
Therefore, the present invention has been made in view of the above
5 problems, and in view of the above circumstances, an object of the present invention
is to provide a novel and improved end structure of a vehicle through which it is
possible to improve load resistance performance in response to collision.
Solution to Problem
10 [0009]
In order to solve the above problem, according to an aspect of the present
invention, there is provided an end structure of a vehicle, including: a beam that
extends in a vehicle width direction; and a connecting stmcture that connects the
beam to a vehicle body frame. In a cross-sectional view perpendicular to the
15 vehicle width direction., the beam includes a first top surface pmi and a first bottom
surface part which face each other, a first side surface part that connects one ends of
the first top surface part and the first bottom surface part, and first flange parts that
m·e formed to protrude vertically outwardly at the other ends of the first top surface
pmi and the first bottom surface part. The beam is fixed to the connecting structure
20 by at least one of bonding of a protrusion that is provided in the connecting stmcture,
protrudes inside the beam, and is atTanged inside the beam to the first top surface
pmi and the first bottom surface pati and bonding of a beam attachment member
provided in the connecting stmcture to the first flange parts.
25
[0010]
In a case where the prottusion is provided .in the connecting stmcture, a
protruding side surface pmt which faces the first side surface part may be formed in
. the protrusion.
[0011]
In a case where the beam attachment member is provided in the connecting
30 structure and the beam attachment member is fixed to the first flange parts, in a
cross-sectional view perpendicular to the vehicle width direction, the beam
PCT/JP2016/052924
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attachment member may include a second top surface pmt and a second bottom
surface pmt which face each other, a second side surface pmt that connects one ends
of the second top surface pmt and the second bottom surface pmt, and second flange
pmts formed to protmde vettically outwardly at the other ends of the second top
5 surface part and the second bottom surface pmt. The first flange pmts and the
second flange pmts may be fixed.
[0012]
The second side surface pmt may be positioned on a vehicle interior side in
a vehicle longitudinal direction with respect to the first flange patts.
10 [0013]
In a case where the beam attachment member is provided in the cmmecting
structure and the beam attaclunent member is fixed to the first flange parts, a first
reinforcing member may be provided in a region of an opening part of the beam that
faces at least the connecting stmcture in the vehicle width direction, and a closed
15 cross section may be formed by the beam and the first reinforcing member in a crosssectional
view perpendicular to the vehicle width direction.
[0014]
In a cross-sectional view perpendicular to the vehicle width direction, the
first reinforcing member may include a first reinforcing member top surface part and
20 a first reinforcing member bottom smface part which face each other, and a first
reinforcing member side surface part that connects one ends of the first reinforcing
member top surface part and the first reinforcing member bottom surface part. The
first reinforcing member may be arranged inside the beam, the first top surface pmt
and the first reinforcing member top surface part inay be fixed, and the first bottom
25 surface pmt and the first reinforcing member bottom surface pmt may be fixed.
[0015]
In the first reinforcing member side surface pmt, a convex part that
protmdes to a vehicle interior side in a vehicle longitudinal direction with respect to
the first flange pmts may be formed.
30 [0016]
At least a pmt of the first reinforcing member side surface part may be in
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contact with the connecting stmcture.
[0017]
A second reinforcing member may be provided in a region of an opening
part of the beam that faces at least the beam attachment member. In a cross-
5 sectional view pe1pendicular to the vehicle width direction, the second reinforcing
member may include a second reinforcing member top surface pmt and a second
reinforcing member bottom surface pmt which face each other, a second reinforcing
member side surface pmt that cormects one ends of the second reinforcing member
top surface part and the second reinforcing member bottom surfuce pmt, and second
10 reinforcing member flange parts formed to protmde ve11ically outwardly at the other
ends of the second reinforcing member top surface part and the second reinforcing
member bottom surface pal1. The second reinforcing member may be ananged
inside the beam. The second reinforcing member flange parts may be fixed to the
frrst side surface part. The second reinforcing member side surface part may be in
15 contact with the bemn attachment member.
[0018]
In a case where the beam attachment member is provided in the connecting
stmcture and the beam attachment member is fixed to the frrst flange parts, the
cmmecting structure may further include a stmcture main body part that is provided
20 to extend in the vertical direction. The beam attachment member may include a
beam attachment surface to which the beam is attached and which includes a bent
portion that bends toward a vehicle interior side in a vehicle longitudinal direction at
an end on the outside in the vehicle width direction, and a main body connecting
surface which includes a surface perpendicular to the beam attachment surface in a
25 plan view and is attached to the structure main body part. At least one third
reinforcing member may be· additionally provided to bridge the structure main body
pmt and the beam attachment surface in a plan view.
[0019]
The bent portion may have a radius of curvature of 50 to 200 mm.
30 . [0020]
The third reinforcing member may be -provided such that a ratio LdL2 of a
5
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length L1 of the third reinforcing member in the vehicle longitudinal direction to a
length L2 of a surface of the structure main body part to which the third reinforcing
member is attached in the vehicle longitudinal direction is 0.8 or more.
[0021]
The structure main body pmt may have a U-shaped cross section in which
an opening pmt is provided in the vehicle width direction in a plan view, and a closed
cross section part whose horizontal cross section shape formed by the structure main
body pmt and the main body connecting surface is a closed cross section may be
further provided.
10 [0022]
In a case where a plurality of third reinforcing members are provided in the
vertical direction, inside the closed cross section part, a reinforcing plate arranged in
accordance with a position of a rear side tip, among tips of the third reinforcing
member, in the vehicle longitudinal direction may be provided. The reinforcing
15 plate may have a shape that extends to the rear side tip of the third reinforcing
member positioned on the uppermost side from the rear side tip of the third
reinforcing member positioned on the lowe1most side among the plurality of third
reinforcing members.
20
25
[0023]
A partition member may be provided to fill a space inside the closed cross
section pmt in a horizontal cross-sectional view of the closed cross section part, and
the partition member may be arranged in accordance with an installation height of at
least one of the third reinforcing members.
[0024]
The end structure of the vehicle may be an underrun protector.
[0025]
In order to solve the above problem, according to another aspect of the
present invention, there is provided an end structure of a vehicle, including: a beam
that extends in a vehicle width direction and a connecting structure that connects the
30 beam and a vehicle body fi-ame. The connecting structure includes a struchire main
body pmt that is provided to extend in a vertical direction, and a beam attaclunent
PCT/JP2016/052924
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member to which the beam is attached. The beam attachment member includes a
beam attachment surface to which the beam is attached and which includes a bent
portion that bends toward a vehicle interior side in a vehicle longitudinal direction at
an end on the outside in the vehicle width direction, and a main body connecting
5 sutface which includes a smface perpendicular to the beam attachment surface in a
plan view and is attached to the structure main body part. At least one reinforcing
member is additionally provided to bridge the structure main body patt and the beam
attachment surface in a plan view.
10 Advantageous Effects oflnvention
15
[0026]
As described above, according to the present invention, it is possible to
improve load resistance performance in response to collision.
Brief Description of Drawings
[0027]
[FIG. 1] FIG. 1 is a schematic view of an undenun protector according to an
embodiment of the present invention.
[FIG; 2] FIG. 2 is a diagram for describing load input positions according to a method
20 of evaluating load resistance performance of an undenun protector.
[FIG. 3] FIG. 3 is a cross-sectional view of an exemplary schematic configuration of
an undenun protector of the related art.
[FIG. 4] FIG. 4 is a perspective view of a schematic configuration of an undernm
protector according to a first embodiment of the present invention.
25 [FIG. 5] FIG. 5 is a cross-sectional view of the underrun protector according to the
first embodi1nent taken along the line V-V in FIG. 4.
[FIG. 6] FIG. 6 is a cross-sectional view of a schematic configuration of a first
. modified example of the unde1mn protector according to the first embodiment.
[FIG. 7] FIG. 7 is a cross-sectional view of a schematic configuration of a second
30 modified example ofthe undenun protector according to the first embodiment.
. [FIG. 8] FIG. 8 is a perspective view of a schematic configuration of an underrun
PCT/JP2016/052924
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protector according to a second embodiment of the present invention.
[FIG. 9] FIG. 9 is a cross-sectional view of the underrun protector according to the
second embodiment taken along the line IX-IX in FIG. 8.
[FIG. 1 0] FIG. 10 is a longitudinal cross-sectional view of the shape of a first
5 reinforcing member of the undenun protector according to the second embodiment.
[FIG. 11] FIG. 11 is a cross-sectional view of a schematic configuration of a first
modified example of the undenun protector according to the second embodiment.
[FIG. 12] FIG. 12 is a cross-sectional view of a schematic configuration of a second
modified example of the undenun protector according to the second embodiment.
10 [FIG. 13] FIG. 13 is a perspective view of a schematic configuration of a third
modified example of the underrun protector according to the second embodiment.
[FIG. 14] FIG. 14 is a cross-sectional view of the undenun protector according to the
second embodiment taken along the line XIV-XIV in FIG. 13.
[FIG. 15] FIG. 15 is a cross-sectional view of a schematic configuration of a fourth
15 modified example of the underrun protector according to the second embodiment.
[FIG. 16] FIG. 16 is a perspective view of a schematic configuration of a fifth
modified example of the underrun protector according to the second embodiment.
[FIG. 17] FIG. 17 is a cross-sectional view of the undenun protector according to the
- second embodiment taken along the line XVII-XVII in FIG. 16.
20 [FIG. 18] FIG. 18 is a cross-sectional view of a schematic configuration of a sixth
modified example of the undenun protector according to the second embodiment.
[FIG. 19] FIG. 19 is a cross-sectional view of an exemplary schematic configuration
of an undenun protector of the related art including a reinforcing member.
[FIG. 20] FIG. 20 is a perspective view of a schematic configuration of a seventh
25 modified example of the underrun protector according to the second embodiment.
[FIG. 21] FIG. 21 is a cross-sectional view of the undenun proteCtor according to the
second embodiment taken along the line XXI-XXI in FIG. 20.
[FIG. 22] FIG. 22 is a cross-sectional view of a schematic configuration of an eighth
modified example of the undemm protector according to the second embodiment.
30 [FIG. 23] FIG. 23 is a diagram showing an example of a state of deformation of the
-underrun protector wheu a load is input to the underrun protector of the related att.
PCT/JP2016/052924
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[FIG 24] FIG 24 is a perspective view of a schematic configuration of an undemm
protector according to a third embodiment of the present invention.
[FIG 25] FIG 25 is a cross-sectional view of the underrun protector according to the
third embodiment taken along the line XXV-XXV in FIG 24.
5 [FIG 26] FIG 26 is a diagram showing an example of a state of deformation of the
undenun protector when a load is input to the underrun protector according to the
third embodiment.
[FIG. 27] FIG. 27 is a perspective view of a schematic configuration of a first
modified example of the underrun protector according to the third embodiment.
10 [FIG 28] FIG 28 is a diagram showing an example of a state of deformation of the
undenun protector when a load is input to the undenun protector according to the
first modified example.
[FIG. 29] FIG 29 is a perspective view of a schematic configuration of a second
modified example of the undenun protector according to the third embodiment.
15 [FIG 30] FIG 30 is a diagram showing an example of a state of deformation of the
undenun protector when a load is input to the undenun protector according to the
second modified example.
[FIG 31] FIG 31 is a perspective view of a schematic configuration of a third
modified example of the undenun protector according to the third embodiment.
20 [FIG. 32] FIG. 32 is a perspective view of a schematic configuration of an undcrrun
protector according to a fourth embodiment of the present invention.
[FIG. 33] FIG. 33 is a cross-sectional view of the undenun protector according to the
fourth embodiment taken along the line XXXIII-XXXIII in FIG. 32.
[FIG 34] FIG. 34 is a cross-sectional view of the underrun protector according to the
25 fomih embodiment taken along the line XXXIV-XXXIV in FIG. 32.
[FIG. '35] FIG. 3:; is a diagram for describing a test method in which a load resistance
performance evaluation test is performed using an underrun protector according to
Experimental Example l.
[FIG. 36] FIG. 36 is a graph showing a relationship between an indentation amount of
30 an indenter and an input load in Example 1 and Comparative Example 1.
[FIG 37] FIG. 37 is a diagram for describing a test method in which a load resistance·
PCT/JP2016/052924
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performance evaluation test is performed using an undenun protector according to
Experimental Example 2.
[FIG. 38] FIG. 38 is a graph showing a relationship between an indentation amount of
an indenter and an input load in Example 2 and Comparative Example 1.
5 [FIG 39] FIG. 39 is a graph showing a relationship between an indentation amount of
an indenter and an input load in Example 7 and Comparative Example 3.
[FIG. 40] FIG. 40 is a graph showing a relationship of a ratio between a length Lt and
a length L2 in a vehicle longitudinal direction of a reinforcing member attachment
surface and a maximum load ratio with respect to an underrun protector of the related
10 att.
Description of Embodiments
[0028]
Hereinafter, (a) preferred embodiment(s) of the present invention will be
15 described in detail with reference to the appended drawings. In this specification
and the appended drawings, structural elements that have substantially the same
function and structure are denoted with the same reference numerals, and repeated
explanation of these structural elements is omitted.
20
[0029]
In addition, in this specification, for example, the "vehicle exterior side in a
vehicle longitudinal direction" refers to the "front side" when an end stmcture of the
vehicle is provided at the fi·ont of the vehicle and refers to the "rear side" when an
end stmcture of the vehicle is provided at the rear of the vehicle. The "vehicle
interior side in a vehicle longitudinal direction" refers to a side opposite to the
25 "vehicle exterior side in a vehicle longitudinal direction." In addition, in this
specificatiun, the expressions "horizontal" and "veftical" include not only precisely
"horizontaP and "ve1tical," but also include substantially horizontal and substantially
veitical. In addition, in this specification, the expression "perpendicular" includes
not only exactly perpendicular (90°) but also substantially perpendicular.
30 [0030]
<<1. Load resistance performance evaluation ofunderrun protector>>
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FIG. 1 is a schematic v1ew of an underrun protector according to an
embodiment of the present invention. As shown in FIG. 1, in a large vehicle VI, an
undenun protector 1 including a beam 2 and a connecting structure 3 is provided.
The underrun protector 1 according to the present embodiment is an example of an
5 end structure of a vehicle. The undernm protector 1 shown in FIG. 1 is provided at
a front lower pmt of the large vehicle VI and is attached to a vehicle body frame (not
shown) with the connecting structure 3 therebetween. The underrun protector I is
provided not only at the front but also the rear of the large vehicle V 1.
10
[0031]
As shown in FIG. I, in the large vehicle VI, a bumper 100 is generally
provided at the front or rear of the vehicle. However, the bumper 100 may be
provided at a position higher than a frame 200 of a passenger vehicle V2.
Therefore, when the large vehicle VI collides with the passenger vehicle V2, the
bumper 100 and the frame 200 do not collide from the fi'Ont, and the large vehicle VI
15 rides over the passenger vehicle V2. In this case, it is not possible for the fran~e 200
20
to absorb the impact energy received from the large vehicle V1, and the cabin of the
passenger vehicle V2 may be deformed. Therefore, it is difficult to ensure the
safety of passengers aboard the passenger vehicle V2.
[0032]
Meanwhile, as shown in FIG. 1, the underrun protector 1 is provided at
substantially the same height as the frame 200 of the passenger vehicle V2. In this
case, when the large vehicle V 1 collides with the passenger vehicle V2 in the vehicle
longitudinal direction, the underrun protector I collides with the frame 200.
Accordingly, the passenger vehicle V2 does not become wedged under the large
25 vehicle VI, and the fiame 200 can absorb the collision energy received from the
large vehicle VI. Therefore, it is possible tci ensure the safety of passengers aboard
the passenger vehicle V2.
[0033]
It is necessary for such an undenun protector to exhibit a mechanism for
30 absorbing collision energy of the passenger vehicle V2 while preventing the
passenger vehicle V2 fi·om becoming wedged under the large vehicle. · That is, there
PCT/JP2016/052924
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is a higher demand for the underrun protector 1 to have load resistance performance
to generate a reaction force by which the passenger vehicle V2 that collides with the
large vehicle VI is cast aside rather than for an effect of absorbing the collision
energy generated when collision with the passenger vehicle V2 occurs. The high
5 load resistance performance is necessary regardless of a collision position in a
vehicle width direction with respect to the beam 2 of the underrun protector I.
However, depending on a position at which a load is input to the beam 2, a
deformation mode occurring in the undenun protector 1 during collision is different.
Therefore, it is necessary to improve the load resistance performance according to a
10 plurality of deformation modes.
[0034]
FIG. 2 is a diagram for describing load input positions according to a
method of evaluating load resistance performance of an undenun protector.
Referring to FIG. 2, the method of evaluating load resistance performance of an
15 undenun protector (a load resistance performance evaluation method) is a method in
which a maximum input load obtained when a load F is input at a position PI at
which the beam 2 is attached to the connecting structure 3 attached to a vehicle body
frame 20 or a position P2 lateral to the attachment position P l in a vehicle width
direction W is evaluated.
20 [0035]
In order to obtain sufficient load resistance performance of the underrun
protector, as described above, it is necessary to respond to a deformation mode of the
beam 2 occurring when a load is input to each collision position. For example,
when the load F is applied to the attachment position PI, the cross section of the
25 beam 2 near the attachment position P l may collapse. · In order to prevent the cross
section of the beam 2 atthe attachment position P l from collapsing, it is necessary to
'_prevent out-of-plane deformation of the beam 2. Iri addition, when the load F is
applied to the position P2, the beam 2 may be deflected near the position P2. In
order to avoid deflection of the beam 2 near the position P2, it is necessary to prevent
30 the beam 2 from being bent.
[0036]
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That is, the performance of the underrun protector as a product is influenced
by the superiority or inferiority of the load resistance performance at the attachment
position PI and the position P2. Therefore, the undenun protector having favorable
load resistance performance is an underrun protector having a high maximum input
5 load at the attachment position P 1 and the position P2.
[0037]
Here, an exemplary configuration of an underrun protector of the related att
will be described. FIG. 3 is a cross-sectional view of an exemplary schematic
configuration of an underrun protector 50 of the related art. As shown in FIG 3, the
10 undenun protector 50 of the related art includes a beam 51 and a bracket 52. The
bracket 52 is attached to a vehicle fi·ame (not shown). The beam 51 is attached to
the bracket 52 so that it is at the vehicle exterior side in the vehicle longitudinal
direction.
15
[0038]
In the case of such a beam shape, when the load F is input to a beam
collision surface, the beam 51 may be deformed as indicated by dashed lines in FIG.
3. In this case, for example, at the position P1 in FIG. 2, the cross section of the
beam 51 may collapse. In addition, when such deformation occurs at the position
P2 in FIG. 2, near a fastening part between the beam 51 and the bracket 52, an anti-
20 collision surface of the beam 51 and the bracket 52 are deformed to be deflected to
the inside of the beam 51.
[0039]
When such deformation occurs, the deformation progresses as an input load
mcreases. Therefore, the cross section of the beam has a strength that is
25 significantly smaller than the inherent strength of the cross section of the beam.
That is, it is not possible for sufficient load rei.istance performance of the underrun
protector to be exhibited.
[0040]
Thus, the inventors conducted extensive studies and invented underrun
30 protectors described in the following embodiments as a Tesult. The underrun
·protector in the present embodiment can improve the load resistance performance at
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any collision position compared to the related art. Underrun protectors according to
embodiments will be described below.
[0041]
Here, while the undenun protector in the present embodiment is an example
5 of an end structure of a vehicle, the present invention is not limited thereto. For
example, a life guard device for preventing an object such as a passenger vehicle
fi·om becoming entangled with a railway vehicle is also an example of the end
structure of the vehicle according to the present invention. While the underrun
protector is described in the present embodiment, the end structure of the vehicle
10 according to the present invention can also be applied to other vehicles and selftravelling
machines. Examples of the other vehicles and self-travelling machines
include two-wheel vehicles, large vehicles such as buses and tractors, trailers,
railway vehicles, construction machines, mining machines, agricultural machines,
general machines, and ships. In addition, materials fotming members of the end
15 structure of the vehicle according to the present invention may be aluminum,
titanium, or stainless steel metal plates in addition to steel plates. In addition, a
material forming the members may be an alloy, a composite material including a
metal and a resin, carbon fibers, or the like.
[0042]
20 <<2. First embodiment>>
FIG. 4 is a perspective view of an exemplary schematic configuration of an
undenun protector 1 according to a first embodiment of the present invention. As
shown in FIG. 4, the underrun protector l according to the present embodiment
includes the beam 2 that extends in the vehicle width direction W and the connecting
25 structure 3 for connecting the beam 2 to the vehicle body frame 20. The connecting
structure 3 according to the'present embodiment is, for example, a stay 4. Here;· in
another embodiment, the connecting stmcture 3 may be a bracket attached to the stay.
The bracket is an example of a beam attachment member in another embodiment.
A pair of left and right connecting structures 3 are provided at least at the front or
30 rear of the vehicle. The beam 2 is provided to bridge the pair of left and right
. connecting structures 3. A material forming the-beam 2 is not limited to a steel
PCT/JP2016/052924
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material as described above and may include various metals, alloys, a composite
material including a metal and a resin, carbon fibers, or the like. Since the load
resistance performance is necessary for the beam 2, it is preferably formed of a high
strength material.
5 [0043]
A pair of stays 4 are formed to extend in a vertical direction V and include a
part formed in a U-shape in a plan view and a protrusion 6 that protrudes inside the
beam 2. In addition, the pair of stays 4 are arranged with·. an interval therebetween
so that opening surfaces 4a face each other inside in the vehicle width direction W.
10 On a part of each of the opening surfaces 4a of the pair of stays 4, a frame attachment
plate 5 is provided to cover an opening. The frame attachment plate 5 is welded to
the stay 4. A bolt hole 21 is formed in the frame attachment plate 5. The frame
attachment plate 5 is fastened to the vehicle body frame 20 through the bolt hole 21
using a bolt. Accordingly, the stay 4 is fixed to the vehicle body frame 20. Here,
15 in the present embodiment, the oonnecting structure 3 includes the stay 4 and the
frame attachment plate 5.
[0044]
FIG. 5 is a cross-sectional view of the undenun protector 1 ar;oording to the
present embodiment taken along the line V-V in FIG. 4. Here, in FIG. 5,
20 deformations of members when a load is input are indicated by dashed lines in the
Image. As shown in FIG. 5, in a cross-sectional view perpendicular to the vehicle
width direction W, the beam 2 according to the present embodiment includes a first
top surface part 2a and a first bottom surface part 2b which face each other and a first
side surface part 2c connecting one ends of the first top surface part 2a and the first
25 bottom surface part 2b. In the present embodiment, the first top surface pmt 2a and
the first bottom smface part 2b are provided to be horizontal. In addition; the first
side surface part 2c is formed to be perpendicular to the first top surface part 2a and
the first bottom surface pmt 2b and has a vettical surface. In addition, at the other
ends (one ends on the side in which the first side surface pmt 2c is not provided) of
30 the first top smface part 2a and the first bottom surface pmt 2b, a pair of first flange
parts 2d that protmde outward in the vertical direction V are provided. Specifically,
PCT/JP2016/052924
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the first flange parts 2d are formed to protrude upward in the vertical direction V at
the other end of the first top sutface part 2a and to protrude downward in the vertical
direction V on the first bottom surface part 2b. That is, the beam 2 according to the
present embodiment has a so-called hat shape in a cross-sectional view perpendicular
5 to the vehicle width direction W.
[0045]
That is, the beam 2 according to the present embodiment has a so-called hat
shape in a cross-sectional view perpendicular to the vehicle width direction W. In
addition, as shown in FIG. 5, bolt holes 8 are formed at central parts of the first top
10 surface patt 2a and the first bottom surface patt 2b in the beam 2.
[0046]
In addition, as shown in FIG. 4 and FIG. 5, the protmsion 6 of the stay 4
includes a protmding top surface part 6a that is formed to face the first top surface
patt 2a and a protmding bottom surface part 6b that is formed to fuce the first bottom
15 surface part 2b. In the present embodiment, the tip of the prottusion 6 is close to
the first side surface part 2c. In addition, the first top surface part 2a and the
protruding top surface part 6a are in contact with each other, and the first bottom
surface part 2b and the protruding bottom surface part 6b are in contact with each
other; In addition, bolt holes 7 are formed at central parts of the prottuding top
20 smface part 6a and the protmding bottom surface part 6b. The prottusion 6 is fixed
to the first top surface pmt 2a and the first bottom surface pmt 2b via the bolt hole 7
and the bolt hole 8 using a bolt 22. Accordingly, the beam 2 is attached to the
vehicle body frame 20 via the stay 4.
25
[0047]
The unde!Tun protector I according to the present embodiment is configured
as described above. In such a configuration, the protrusion 6 is arranged inside the
beam 2 having an open cross section and is fixed to the first top surface part 2a and
the first bottom surface part 2b. Accordingly, the load F applied due to collision is
transmitted from the first top surface patt 2a and the first bottom surface patt 2b to
30 the protrusion 6 in the in-plane direction as a shear force. Therefore, since the load
applied to the first side surface part 2c of the beam 2 is transmitted to the stay 4
PCT/JP2016/052924
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through the first top surface part 2a and the first bottom surface part 2b, a burden
applied to the first side surface part 2c is reduced. Therefore, it is possible to
prevent the progress of local deformation of the cross section of the beam 2 and
prevent the input load from being dispersed. As a result, the maximum load value
5 can be increased compared to the related mt in a load resistance performance
evaluation test, and it is possible to improve the load resistance performance of the
undenun protector. That is, it is possible to improve the load resistance
pe1formance with respect to the load input to a collision surface (surface on the
vehicle exterior side of a first side surface part 2c) of the beam 2 at the attachment
10 position PI on the beam 2 shown in FIG. 2.
[0048]
In addition, in the above embodiment, the beam 2 includes the pair of first
flange parts 2d. On the other hand, counter load input ends of the first top surface
part 2a and the first bottom surface pmt 2b near a load input point of the beam 2
15 roughly undergo tensile deformation. Therefore, when the beam 2 having no first
flange part 2d is made of a highly tensile material having high strength and low
ductility, since an end of at least one of the first top surface part 2a and the first
bottom surface pmt 2b may break, there is a possibility of a load resistance
·--performance improvement effect being degraded more than expected. Therefore,
20 when the first flange pmt 2d is formed in the beam 2, it is possible to prevent the end
from breaking.
[0049]
While the underrun protector I according to the present embodiment has
been described above, the present invention is not limited thereto. For example, the
25 shape of the stay 4 is not limited to the example described in the above embodiment.
For example, the tip of the protrusion 6 of the stay 4 is prefenibly close to the first
side surface pmt 2c of the beam 2 as described above. However, the position or the
shape of the tip of the protrusion 6 inside the beam 2 may be appropriately changed
according to the necessary load resistance performance, beam shape, and the like.
30 [0050]
(First modified example)
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FIG. 6 is a cross-sectional view of a schematic configuration of a first
modified example of the undenun protector 1 according to the present embodiment.
As shown in FIG. 6, a protmding side surface pati 6c connecting tips of the
protmding top surface part 6a and the protmding bottom surface part 6b may be
5 provided. In this case, the protruding side surface part 6c may be provided at a
position in contact with an inner side surface of the first side surface part 2c. In this
case, when a load is input, it is possible to prevent the deformation of the first side
surface part 2c and prevent out-of-plane deformation of the protmsion 6 (for example,
the out-of-plane deformation of the protmding top surface part 6a or the protmding
10 bottom surface part 6b). Therefore, it is possible to further improve the load
resistance performance.
[0051]
(Second modified example)
In addition, while the beam 2 includes the pair of first flange parts 2d in the
15 above embodiment, the first flange parts 2d may not be formed in the beam 2. FIG.
7 is a cross-sectional view of a schematic configuration of a second modified
example of the undermn protector 1 according to the present embodiment. In this
case, it is possible to prevent the deformation of the beam 2 to some extent, and it is
possible to improve the load resistance performance of the undenun protector.
20 However, as described above, when the beam 2 in which no first flange part 2d is
formed is made of a highly tensile material having high strength and low ductility,
since an end of at least one of the first top surface part 2a and the first bottom surface
pmi 2b may break, there is a possibility of a load resistance performance
improvement effect being degraded more than expected. Therefore, in order to
25 prevent the end from breaking as described above, the first flange part 2d is
pi'i:ferably formed in the first top surface pmi 2a and the fii"st bottom surface pmi 2b.
[0052]
In addition, while the first top surface part 2a and the protruding top surface
pmi 6a, and the first bottom surface part 2b and the protruding bottom surface part 6b
30 are fixed using the bolt 22 in the above embodiment, positions of the bolt hole 7 and
the bolt hole 8 .are not limited to the example described in the above embodiment.
i Lf1
PCT/JP2016/052924
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Depending on the shape of the beam 2 or the shape of the stay 4, both patis may be
fixed at other positions. Alternatively, both parts may be fixed by, for example,
welding, instead of fixing using a bolt. Howevet; when a bolt is used, since it is
easy to exchange only the damaged beam 2 alone, maintainability is improved.
5 [0053]
In addition, while the protrusion 6 is formed in contact with the first top
surface pati 2a and the first bottom surface pati 2b in the above embodiment, the
protrusion 6 and the first top surface pati 2a and the first bottom surface pati 2b may
not be in contact with each other. The protrusion 6 is fixed to the first top surface
10 · part 2a and the first bottom surface pati 2b. In addition, at1 insettion length of the
protrusion 6 from an opening part of the beam 2 to the inside of the beam 2 is not
particularly limited. For example, the tip of the protmsion 6 is not necessarily in
contact with the first side smface part 2c. However, when the insertion length of
the protmsion 6 is short, there is a possibility of out-of-pla11e deformation occurring
15 at at least one of the first top surface part 2a a11d the first bottom surface part 2b
when a load is input. Therefore, it is preferable that the insertion length of the
protrusion 6 be as long as possible.
[0054]
In addition, while the stay 4 is provided in contact with the first flange pali
20 2d of the beam 2 in the above embodiment, the stay 4 and the first flange part 2d do
not necessarily come in contact with each other. However, when the stay 4 and the
first fla11ge pati 2d are in contact with each other, a load is transmitted from the first
flange part 2d to the stay 4 when a load is input. Therefore, since the load
transmitted to the stay 4 is increased, it is possible to improve the load resistance
25 performance.
[0055]
In addition, while the stay 4 includes one pati in the above embodiment, it
may be an assembly including a plurality of parts. The stmcture of the stay 4 is not
particularly limited as long as the stay 4 fmms the protrusion 6 that can be arranged
30 inside the beam 2.
[0056]
il
~
"
5
PCT/JP2016/052924
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The underrun protector 1 according to the first embodiment of the present
invention has been described above.
[0057]
<<3. Second embodiment>>
Next, an underrun protector 1 according to a second embodiment of the
present invention will be described.
[0058]
FIG. 8 is a perspective view of a schematic configuration of the undenun
protector I according to the second embodiment of the present invention. Since
10 functions of the beam 2, the stay 4, the frame attachment plate 5, and the vehicle
body frame 20 which are basic components of the underrun protector 1 are the same
as those in the first embodiment of the present invention, description thereof will be
omitted. Here, unlike the first embodiment of the present invention, the stay 4
according to the present embodiment has no protrusion 6 and is formed to extend in
15 the vertical direction V.
[0059]
As shown in FIG. 8, L-shaped brackets 10 are provided on surfaces that face
the opening smfaces 4a of the pair of stays 4. The bracket I 0 includes a flat plate
stay attachment part 1 Oa and a flat plate beam attachment part 1 Ob perpendicular to
20 the stay attachment part 1 Oa. The stay attachment part 1 Oa is fixed on a side surface
of the stay 4. In addition, the beam attachment pmt 1 Ob is fixed in a direction in
which it comes in contact with a back surface (anti-collision surface) of the beam 2.
Here, in the present embodiment, the bracket 10 is an example of a beam attachment
member and is a pmt of the connecting structure 3.
25 [0060]
FIG. 9 is a cross-sectional view of the· underrun protector 1 according to the
present embodiment taken along the line IX-IX in FIG. 8. ·.As shown in FIG. 9, a
first reinforcing member 9 that covers the whole or a patt of the back surface of the
beam 2 is provided between the beam 2 and the bracket I 0. A closed cross section
30 is formed by the beam 2 and the first reinforcing member 9 in a cross-sectional view
perpendicular to the vehicle width direction W. In the example shown in FIG. 9, the
PCT/JP2016/052924
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first reinforcing member 9 is formed in a rectangular shape to extend in the vehicle
width direction W.
[0061]
In addition, as shown in FlG. 9, a bolt hole 11 is formed in the beam
5 attachment part lOb of the bracket 10. In addition, in the first reinforcing member 9,
a bolt hole 12 corresponding to a bolt diameter is formed to fix the first flange part
2d and the bracket 10. FIG. 10 is a longitudinal cross-sectional view of the shape of
the first reinforcing member of the underrun protector according to the present
embodiment. As shown in FIG. 10, the beam 2, the bracket 10, and the first
10 reinforcing member 9 are fastened using a bolt (not shown) via the bolt hole 12.
[0062]
The underrun protector 1 according to the present embodiment is configured
as described above. In such a configuration, the beam 2 has a hat shape, and the
beam 2 and the bracket 10 are fixed at the first flange part 2d that protmdes outward
15 in the vertical direction V. Therefore, when the load F is input, a moment M1 is
generated around a point C in the drawing such that the tip of the first flange part 2d
rotates to a collision surface side. In this case, the end of the first reinforcing
member 9 and the end of the bracket 10 fixed to the first flange part 2d are deformed
to rotate to the collision surface side.
20 [0063]
The moment M1 is a moment in a direction opposite to a moment M2 that is
applied so that the first reinforcing member 9 and the bracket 10 deflect to the inside
of the beam 2. Therefore, the moments cancel each other out and deflection of the
first reinforcing member 9 and the bracket 10 to the inside of the beam is prevented.
25 [0064]
Accordingly, it is possible to prevent local ddormation of the cross section
. of the beam 2 in contrast to in the related art in the vicinity of the position P2 lateral
to the attachment position of the beam 2 with respect to the input load. As a result,
the maximum load value can be increased compared to the related mt at the position
30 P2 in the load resistance perfmmance evaluation test. Therefore, it is possible to
improve- the load resistance performance of the undernm protector ..
PCT/JP2016/052924
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[0065]
While the underrun protector 1 according to the present embodiment has
been described above, the present invention is not limited thereto. For example, the
shapes of the bracket 10, the stay 4, and the first reinforcing member 9 are not
5 limited to the example described in the above embodiment. The shapes of these
members are appropriately changed depending on the shape of the vehicle body
frame 20, or the necessary performance of the undenun protector 1. For example,
while the flat plate first reinforcing member 9 is provided in contact with the first
flange patt 2d in the above embodiment, the first reinforcing member 9 may be
10 provided inside the beam 2 (for example, between the top surface patt 2a and the
bottom surface part 2b of the beam 2). That is, the first reinforcing member 9 is
provided at an opening part of the beam 2 so that a closed cross section is formed by
the beatn 2 and the first reinforcing member 9 in a cross-sectional view perpendicular
to the vehicle width direction W. Accordingly, it is possible to improve the load
15 resistance performance. Modified examples of the first reinforcing member 9 will
be described below.
[0066]
In addition, while the beam 2 and the bracket 10 m·e fixed using bolts 23 in
the above embodintent, the positions of the bolt holes provided in these members are
20 not limited to the example described in the above embodiment. In addition, both
parts may be fixed by welding, instead of fixing using a bolt. However, when a bolt
is used, since it is easy to exchange only the damaged beam 2 alone, maintainability
is improved.
[0067]
25 (First modified example)
In addition, while the first reinforcing member 9 is provided on the back
surface side (anti-collision surface side) of the beam 2 in the above embodiment, the
present invention is not limited thereto. For example, the first reinforcing member
9 may not be provided in the underrun protector I, and the beam 2 may be directly
30 attached to the bracket 10. FIG 11 is a cross-sectional view of a schematic
· configuration of a first modified example of the underrun protector 1 according to the
PCT/JP2016/052924
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present embodiment. As shown in FIG. 11, even if the beam 2 is directly attached
to the bracket 10, it is possible to prevent deflection of each member to the inside of
the beam 2 as in the above embodiment. Therefore, it is possible to improve the
load resistance performance of the undenun protector.
5 [0068]
(Second modified example)
In addition, while the beam 2 is attached to the bracket 10 in the first
modified example of the undenun protector according to the above embodiment, the
present invention is not limited thereto. For example, the bracket 10 may not be
10 provided in the undenun protector 1, and the beam 2 may be directly attached to the
stay 4. FIG. 12 is a cross-sectional view of a schematic configuration of a second
modified example of the undenun protector 1 according to the present embodiment.
Even if the beam 2 is directly attached to the stay 4, it is possible to prevent
deflection of each member to the inside of the beam 2 as in the above embodiment.
15 Therefore, it is possible to improve the load resistance performance of the underrun
protector
[0069]
In addition, regardless of the configuration (the bracket 10 or the stay 4) of
the connecting· structure 3 shown in the first modified example and the second
20 modified example, it is preferable that the beam 2 have a hat shape, and the beam 2
and the connecting structure 3 be fixed at the first flange part 2d. Thus, it is
possible to improve the load resistance performance of the underrun protector.
However, when the first reinforcing member 9 is additionally provided, it is possible
to further improve the load resistance performance. Therefore, the first reinforcing
25 member 9 is preferably provided in the undenun protector 1.
[0070]
(Third modified example)
In addition, in order to improve the load resistance performance more
effectively using the first reinforcing member 9, it is necessmy to further refine the
30 ·shape or arrangement of the first reinforcing member 9. For example, in the
· underrun protector 1 shown in FIG. 9, it is possible to prevent deformation to the
PCT/JP2016/052924
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inside of the beam in contrast to in the related mt. However, the first top surface
part 2a and the first bottom surface patt 2b may be easily deformed to the inside of
the cross section near the first flange patt 2d. Therefore, the inventors conducted
more extensive studies of the shape or arrangement of the first reinforcing member 9
5 and developed the underrun protector I to be described below.
[0071]
FIG. 13 and FIG. 14 are a perspective view of a schematic configuration of a
third modified example of the undenun protector I according to the present
embodiment and a cross-sectional view taken along the line XIV-XIV. As shown in
10 FIG. 14, the first reinforcing member 9 according to the present modified example
has a U-shaped cross section including a first reinforcing member top surface part 9a
and a first reinforcing member bottom surface part 9b which face each other, and a
first reinforcing member side surface part 9c connecting one ends of the first
reinforcing member top surface part 9a and the first reinforcing member bottom
15 surface part 9b in a cross-sectional view perpendicular to the vehicle width direction
w.
[0072]
In the first reinforcing member 9, the first reinforcing member top surface
part 9a and the first reinforcing member bottom surface part 9b, and the first top
20 surface pmt 2a and the first bottom surface part 2b are bonded respectively by, for
example, welding. In addition, a closed cross section is formed by the beam 2 and
the first reinforcing member 9. In addition, in the example shown in FIG. 13 and
FIG. 14, the first reinforcing member side surface patt 9c is arranged in contact with
the beam attachment part I Ob of the bracket 10. When the first reinforcing member
25 9 is ananged in this manner, it is possible to cause the action of inhibiting the
deformation of the first top surface' part 2a and the first bottom surface part2b to the
inside of the cross section near the first flange part 2d. Here, a method of fixing the
first reinforcing member top surface patt 9a and the first reinforcing member bottom
surface patt 9b, and the first top surface patt 2a and the first bottom surface patt 2b is
· 30 not limited to welding.
[0073]
PCT/JP2016/052924
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In addition, as shown in FIG. 14, the first reinforcing member 9 is preferably
arranged so that the first reinforcing member side surface pmt 9c is positioned on the
first flange patt 2d side. For example, in the first reinforcing member top surface
pmt 9a and the first reinforcing member bottom surface pmt 9b, ends on the side in
5 which the first reinforcing member side surface patt 9c is not provided are preferably
provided to be positioned on the vehicle exterior side in a vehicle longitudinal
direction L with respect to the first reinforcing member side surface pmt 9c.
Accordingly, a moment M3 for deforming the first reinforcing member side surface
part 9c to the inside of the cross section is generated and the action of the first
10 reinforcing member top surface part 9a and the first reinforcing member bottom
surface part 9b deforming to the outside of the cross section occurs. Therefore, it is
possible to fi.uther prevent defonnation to the inside of the cross section of the first
top surface part 2a and the first bottom smface part 2b. As a result, it is possible to
further improve the load resistance perfonnance.
15 [0074]
Here, the shape of the cross section of the first reinforcing member 9 is not
limited to the U-shape shown in FIG. 13 and FIG 14. That is, as long as the first
reinforcing member 9 includes the first reinforcing member top surface pmt 9a and
the-first reinforcing member bottom surface part 9b which· face each other and the
20 first reinforcing member side surface part 9c connecting one ends of the first
reinforcing member top surface pmt 9a and the first reinforcing member bottom
surface part 9b, and the first reinforcing member top surface part 9a and the first top
surface part 2a, and the first reinforcing member bottom surface part 9b and the first
bottom surface part 2b are fixed, it is possible to improve the load resistance
25 performance. For example, if a structure in which a recess (not shown) is provided
in the first reiliforeing memi.Jer side surface part 9c is used, the sarrie ·effect can be
obtained.
[0075]
(Fourth modified example)
30 In addition, the first reinforcing member side surface part 9c is preferably in
contact with the beam attachment patt 1 Ob of the bracket 10. Accordingly, it is
PCT/JP2016/052924
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possible to further prevent out-of-plane deformation of the first reinforcing member 9
and the beam attachment part 1 Ob. Therefore, it is possible to further improve the
load resistance performance. Here, when a part of the first reinforcing member side
surface part 9c is in contact with the beam attachment part 1 Ob, the effect of
5 preventing the out-of-plane deformation described above may occur. FIG. 15 is a
cross-sectional view of a schematic configuration of a fourth modified example of
the underrun protector 1 according to the present embodiment. As shown in FIG.
15, in the first reinforcing member 9, a first reinforcing member convex pmt 9d may
be further provided at the central patt of the first reinforcing member side surface
10 part 9c. When the first reinforcing member convex part 9d comes in contact with
the beam attachment part 1 Ob, it is possible to obtain the effect of preventing
out-of-plane defomtation of the first reinforcing member 9 and the beam attachment
part 1 Ob. In addition, in order to inhibit deformation of the first top surface part 2a
and the first bottom surface part 2b to the inside of the cross section near the first
15 flange part 2d, the first reinforcing member top surface part 9a and the ftrst
reinforcing member bottom smface part 9b are preferably arranged near the first
flange part 2d.
20
[0076]
- (Fifth modified exantple)
In addition, when a load is input to the beam 2 according to the present
embodiment shown in FIG. 9, the beam attachment part lOb may be deformed in a
wave shape. Accordingly, out-of-plane deformation is induced, which may serve as
a factor inhibiting load resistance performance improvement. Therefore, the
inventors conducted more extensive studies of the shape of the beam attachment part
25 1 Ob and developed the underrun protector 1 to be described below .
[0077] . . ,_-,.
FIG. 16 and FIG. 17 are a perspective view of a schematic configuration of a
fifth modified example of the underrun protector 1 according to the present
embodiment and a cross-sectional view taken along the line XVII-XVII. As shown
30 in FIG. 17, in the bracket 10 according to the present modified example, the shape of
the beam attachment part 1 Ob has substantially a hat shape in cross section in a crossI'
PCT/JP2016/052924
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sectional view perpendicular to the vehicle width direction W. In the example
shown in FIG. 16 and FIG. 17, the beam attachment pmt lOb includes a second top
surface part 1 Oc and a second bottom surface part 1 Od, and a second side surface pmt
1 Oe connecting one ends of the second top surface part 1 Oc and the second bottom
5 surface pmt lOd, and a pair of second flange parts !Of that are formed to protrude
outward in the vertical direction V at the other ends (one ends on the side in which
the second side surface pmt 1 Oe is not provided) of the second top surface part 1 Oc
and the second bottom surface part 1 Od. A second flange part 1 Of and the first
flange part 2d are fastened using, for example, bolts (not shown). Therefore, the
10 beam 2 and the bracket 1 0 are fixed. Here, the method of fixing the beam 2 and the
bracket 1 0 is not limited to the fastening using a bolt. In addition, while the second
top surface part 1 Oc and the second bottom surface part 1 Od are formed to be inclined
with respect to the horizontal plane in the example shown in FIG. 16 and FIG. 17, the
angle of inclination of the second top surface part 1 Oc and the second bottom surface
15 part lOd with respect to the horizontal plane is appropriately changed according to
the necessary load resistance performance and the surrounding margin.
[0078]
In the bracket 10, since the bemn attachment part lOb has substantially a
hat -shaped cross section, the rigidity in cross section and strength increase compared
20 to the flat plate beam attachment part. Therefore, it is possible to inhibit wavy
out-of-plane deformation in the bracket 10. In addition, as shown in FIG. 17, when
the moment M2 generated in the beam attachment pmt lOb and the moment M1
generated in the first flange part 2d are opposite to each other, the effect of inhibiting
mutual deformation can be obtained. .Accordingly, it is possible to improve the load
25 resistance performance.
[00?9]
In addition, when the beam attachment part 1 Ob has substantially a hatshaped
cross section, a second side surface part lOe is desirably positioned on the
vehicle interior side (the vehicle interior side in the vehicle longitudinal direction L
30 with respect to the first flange pmt 2d) relative to an open cross section of the beam 2
as shown in FIG. 17. When the beam attachment part lOb has such a shape, it is·
PCT/JP2016/052924
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possible to increase a cross-sectional area of the closed cross section formed by the
beam 2 and the bracket 10 in a cross-sectional view perpendicular to the vehicle
width direction W. Accordingly, since the bending rigidity and strength of the beam
2 increase, it is possible to improve the load resistance performance.
5 [0080]
In addition, when the beam attachment part 1 Ob has substantially a hatshaped
cross section, the stay attachment part 1 Oa and the beam attachment part 1 Ob
may be different members. However, in this case, the costs for assembling the stay
attachment part 1 Oa and the beam attachment part 1 Ob increase. Therefore, the stay
10 attachment part lOa and the beam attachment part 1 Ob are preferably formed as the
integral bracket 1 0.
[0081]
(Sixth modified example)
In addition, when the beam attachment part lOb has substantially a hat-
15 shaped cross section, the first reinforcing member 9 may be further provided inside
the beam 2. FIG. 18 is a cross-sectional view of a schematic configuration of a
sixth modified example of the underrun protector 1 according to the present
embodiment. As shown in FIG. 18, in the first reinforcing member side surface part
9c, the first reinforcing member convex part 9d that protrudes toward the second side
20 surface part 1 Oe (the vehicle interior side in the vehicle longitudinal direction L with
respect to the first flange part 2d) of the beam attachment part 1 Ob is preferably
provided. That is, the first reinforcing member 9 includes the first reinforcing
member top surface patt 9a and the first reinforcing member bottom surface part 9b
which face each other and the first reinforcing member side surface part 9c
25 connecting one ends of the first reinforcing member top surface part 9a and the first
•· ieii:J.forcing member bottom surface part 9b in a doss-sectional view perpendicular to
the vehicle. width direction W. A part of the first reinforcing member side surface
part 9c preferably protrudes to the second side surface part 1 Oe. In this form, it is
possible to increase a cross section of the closed cross section formed by the beam 2
30 and the first reinforcing member 9 in a cross-sectional view perpendicular to the
vehicle width direction W. Therefore, since the bending rigidity and strength of the
PCT/JP2016/052924
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beam 2 can increase, it is possible to improve the load resistance performance. In
addition, as described above, a patt of the first reinforcing member side surface patt
9c is more preferably in contact with the second side surface part 1 Oe. Thus, it is
possible to prevent out-of-plane deformation of the first reinforcing member 9 and
5 the beam attachment part lOb. In addition, in order to inhibit deformation of the
first top surface patt 2a and the first bottom surface part 2b to the inside of the cross
section near the first flange patt 2d, the first reinforcing member top surface patt 9a
and the first reinforcing member bottom surface patt 9b are preferably arranged near
the first flange part 2d.
10 [0082]
(Seventh modified example)
In an undenun protector 60 of the related art, a hat-shaped reinforcing
member 63 shown in FIG. 19 may be provided. The hat-shaped reinforcing member
63 includes a top surface part 63a and a bottom surface part 63b which face each
15 other, and is ananged to bridge a collision surface a11d a11 a11ti-collision surface of a
beam 61 having a rectangular cross section. Accordingly, reinforcement for
preventing deformation of the collision surface and the anti-collision surface is
performed.
20
[0083]
When the beam attachment part 1 Ob has substantially a hat-shaped cross
section, the reinforcing member shown in FIG. 19 may be provided inside a closed
cross section formed by the beam 2 and the beam attachment part 1 Ob.
[0084]
FIG. 20 and FIG. 21 are a perspective view of a schematic configuration of a
25 seventh modified example of the underrun protector 1 according to the present
eml.Jodiment and a .cross-sectional view taken along the llne XXI-XXI. As shown
in FIG. 21, a second reinforcing member 90 includes a se~,;ond reinforcing member
top surface part 90a and a second reinforcing member bottom surface part 90b which
face each othet; a second reinforcing member side surface part 90c connecting one
30 ends of the second reinforcing member top surface patt 90a and the second
reinforcing member bottom surface part 90b, and a pair of second reinforcing
PCT/JP20 16/052924
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member flange parts 90e that protmde outward in the vertical direction V formed at
the other ends (one ends on the side in which the second reinforcing member side
surface part 90c is not provided) of the second reinforcing member top surface part
90a and the second reinforcing member bottom surface part 90b in a cross-sectional
5 view perpendicular to the vehicle width direction W. The second reinforcing
member side surface part 90c of the second reinforcing member 90 is positioned on
the vehicle interior side (the vehicle interior side in the vehicle longitudinal direction
L with respect to the. first flange part 2d) relative to the open cross section of the
beam 2. In addition, the second reinforcing member flange part 90e and the first
10 side smface part 2c are fixed by, for example, welding. Here, a method of fixing
the second reinforcing member flange part 90e and the first side surface pmi 2c is not
limited to welding. In addition, while the second reinforcing member top surface
part 90a and the second reinforcing member bottom surface part 90b are formed to
be inclined with respect to the horizontal plane in the example shown in FIG 21, the
15 angle of inclination of the second reinforcing member top surface part 90a and the
second reinforcing member bottom surface part 90b with respect to the horizontal
plane is appropriately changed according to the necessary load resistance
performance, beam shape, and the like.
[0085]
20 When the second reinforcing member 90 is provided, reinforcement for
supporting the collision surface (the first side surface pali 2c) is possible.
Furthermore, since a cross-sectional area can increase in a cross-sectional view
perpendicular to the vehicle width direction W, the bending rigidity and strength of
the beam 2 can increase. Therefore, it is possible to reduce the weight and improve
25 the load resistance performance of the undenun protector 1. Here, in the example
shown in FIG. 21, the second reinforeihg rhember siue surface pa1t 90c of the second
reinforcing member 90 is arranged in contact with the second side surface part 1 Oe of
the beam attachment part 1 Ob, but both may not be completely in contact with each
other. That is, a gap may be provided between the second reinforcing member side
30 surface part 90c and the second side surface part 1 Oe in a range in which
reinforcement for supporting the collision surface is possible. However, as
PCT/JP2016/052924
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described above, in order to prevent out-of-plane deformation of the second
reinforcing member 90 and the beam attachment part 1 Ob, the second reinforcing
member side surface part 90c is preferably in contact with the second side surface
part lOe.
5 [0086]
In addition, when the first reinforcing member convex patt 9d shown in FIG.
18 is provided or when the second reinforcing member 90 having a hat -shaped cross
section shown in FIG. 21 is provided, it is necessary to avoid interference between
the stay 4 and the second reinforcing member 90. In order to avoid interference, in
10 the stay 4, a recess (not shown) for avoiding interference with the second reinforcing
member 90 may be provided or a notch (not shown) may be provided. In addition,
a recess formed of a member different from the stay 4 may be provided in the stay 4.
However, when the notch is provided, the strength of the stay 4 may decrease. In
addition, when a recess of the stay 4 is formed of a separate member, since it is
15 necessary to assemble the stay 4 and the recess, costs increase_ Therefore, when a
recess is provided in the stay 4, it is preferable that the stay 4 and the recess be
integrally formed.
[0087]
In addition, a protruding distance D2 of the first side surface part 2c in the
20 vehicle longitudinal direction L from the beam attachment surface 1 Ob in the form
(referred to as the present form) shown in FIG. 21 and a protruding distance D1 of the
beam 61 having a rectangular cross section in the vehicle longitudinal direction L
from a beam attachment surface 62 in the form (referred to as a form of the related
att) shown in FIG. 19 are the same. In this case, the present form has a larger cross-
25 sectional area of the closed cross section surrounded by the beam 2 and the beam
attachment surface 1 Ob than the form of the related art in a cross-sectional view
perpendicular to the vehicle width direction \V. That is, when the position of the
first side surface part 2c in the vehicle longitudinal direction L is restricted, it is
possible to increase a closed cross-sectional area surrounded by the beam 2 and the
30 beam attachment surface 1 Ob without inhibiting the restriction.
{0088)
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(Eighth modified example)
FIG. 22 is a cross-sectional view of a schematic configuration of an eighth
modified example of the underrun protector 1 according to the present embodiment.
Referring to FIG. 22, when the cross-sectional area of the closed cross section fotmed
5 by the beam 2 and the beam attachment surface 1 Ob is the same as the cross-sectional
area of the closed cross section formed by the beam 61 having a rectangular cross
section of the form of the related mi shown in FIG. 19, the protruding distance D2 of
the present form is shorter than the protruding distance D1 of the form of the related
art. That is, the size of the underrun protector is more compact than in the related
10 art while ensuring the load resistance performance. Therefore, it is possible to
reduce the weight and improve the degree of freedom of vehicle design.
[0089]
The underrun protector 1 according to the second embodiment of the present
invention has been described above.
15 [0090]
In the first embodiment and the second embodiment, the beam 2 has a hat
shape, and the beam 2 is fixed to the connecting structure 3 so that the first side
surface part 2c is positioned on the vehicle exterior side in the vehicle longitudinal
direction L. That is, the first side surface part 2c is a collision surface:
20 [0091]
In this case, for example, as shown in the first embodiment, the beam 2 may
be fixed to the connecting structure 3 by bonding of at least one of the first top
surface pmi 2a and the first bottom surfuce pmi 2b to the protrusion 6 that protrudes
inside the beam 2. In addition, for example, as shown in the second embodiment,
25 the beam 2 may be fixed to the connecting structure 3 by bonding of the first flange
part 2d and the connecting structure 3. ·· In addition, the beam 2 and the connecting
structure 3 may be fixed by bonding as in the first embodiment and the second
embodiment.
[0092]
30 · For example, in order to improve the load resistance of the attachment
. . position P 1 on the beam 2, the connecting structure· 3 may be arranged inside the
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beam 2 as in the first embodiment. Thus, it is possible to prevent the cross section
from collapsing at the above attachment position. In addition, in order to improve
the load resistance of the position P2 lateral to the attachment position of the beam 2
in the vehicle width direction W, the connecting structure 3 may be arranged in
5 contact with the first flange part 2d of the beam 2 as in the second embodiment.
Thus, it is possible to prevent deflection of the beam 2. In this manner, either or
both of the first embodiment and the second embodiment can be selected according
to the collision form in which improvement of the load resistance is desired. That is,
it is possible to desirably improve the load resistance performance of the undenun
10 protector 1.
[0093]
Here, the present invention is not limited to the example described in the
above embodiment. For example, while the first top surface part 2a and the first
bottom surface part 2b are in a horizontal state in the above embodiment, at least one
15 of the first top surface part 2a and the first bottom surface part 2b may not be in a
horizontal state. For example, according to the necessary load resistance
performance, the first top surface pmt 2a and the first bottom surface part 2b may be
provided in inclined states so that angles formed between the first side surface part
2c, and the first top surface part 2a and the first bottom surface part 2b are obtuse
20 angles. Also in this case, it is possible to improve the load resistance performance
compared to the underrun protector including a beam having a rectangular cross
section.
25
[0094]
<<4. Third embodiment>>
Next, an undenun protector 1 according to a third embodiment of the
present invention will be describeJ.
[0095]
FIG. 23 is a diagram showing an example of a state of deformation of an
undenun protector 71 of the related art when a load is input to the underrun protector
30 71. As shown in FIG. 23, the undenun protector 71 of the related art includes, for
example, a connecting stmcture 72 (for example, a stay and a bracket) attached to a
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vehicle frame, a beam 73 that extends in the vehicle width direction W and is
attached to a beam attachment surface of the connecting structure 72, and a
reinforcing member 7 4 that is provided to bridge the connecting structure 72 and the
beam 73. The load resistance performance is improved by providing the reinforcing
5 member 74.
[0096]
However, as shown in FIG. 23, when the beam attaclnnent surface of the
connecting structure 72 is formed in a flat plate, if the load F is input to the outside in
the vehicle width direction W relative to the attachment position of the beam 73, the
10 stress concentrates on the edge of the tip of the beam attaclnnent surface. Therefore,
the beam 73 is bent at the edge. In this case, since the cross section of the beam 73
may collapse, it is difficult for sufficient load resistance performance to be exhibited.
The inventors conducted extensive studies and developed the underrun protector 1
according to the present embodiment to be described below as a result.
15 [0097]
FIG 24 is a perspective view of a schematic configuration of the underrun
protector 1 according to the third embodiment of the present invention. As shown
in FIG. 24, the underrun protector 1 according to the present embodiment includes
the· beam 2 having a hat-shaped cross section that extends in the vehicle width
20 direction W and the connecting structure 3 for attaching the beam 2 to the vehicle
body frame 20. The beam 2 is fixed to the vehicle body frame 20 with the
connecting structure 3 therebetween. In the present embodiment, the connecting
structure 3 includes the stay 4 that is formed to extend in the ve1tical direction V, the
L-shaped bracket 10 provided between the beam 2 and the stay 4, and a third
25 reinforcing member 15. Here, while the beam 2 has a closed cross-sectional shape
alone in a cross-sectional VieW perpendicular to the vehicle width direction W in tlle
example shown in FIG. 24, the beam 2 may have a hat-shaped cross section.
[0098]
FIG 25 is a cross-sectional view of the underrun protector 1 according to
30 the present embodiment taken along the line XXV-XXV in FIG. 24. As shown in
FIG. 24 and FIG. 25, the stay 4 is formed in a U-shape in a plan view. An opening
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part of the stay 4 is provided to face the inside in the vehicle width direction W. A
patt of the opening part of the stay 4 is covered with the surface I Oa (corresponding
to the stay attachment sutface lOa) on the vehicle body frame side of the bracket 10.
The tip of the surface I Oa on the vehicle body frame side of the bracket I 0 is fixed
5 outside a side wall 4c of the stay 4 by, for example, welding. In addition, the
surface to which the beam 2 is attached (hereinafter referred to as a "beam
attachment surface I Ob") which is a surface perpendicular to the surface I Oa on the
vehicle body frame side of the bracket I 0 is fixed to a rear surface 4b of the stay 4 by,
for example, welding. Therefore, the bracket 10 is fixed to the stay 4, and a part
10 whose horizontal cross-sectional shape is a closed cross section (hereinafter referred
to as a "closed cross section part 3b") is formed by the surface lOa on the vehicle
body frame side of the bracket 10 and the stay 4. The bracket 10 may be fixed to
the side wall 4c of the stay 4. In this case, the closed cross section part 3b is not
fonned by the bracket 10 and the stay 4. However, when the closed cross section
15 part 3b is formed, it is possible to prevent deformation of the stay 4 due to a torsional
moment generated in the stay 4 in the event of collision. Therefore, as shown in
FIG. 25, the bracket 10 and the stay 4 are preferably provided so that the closed cross
section part 3b is formed.
20
[0099]
In addition, referring to FIG. 24, the frame attachment plate 5 to which the
vehicle body frame (not shown) is attached is provided in an upper part of the stay 4.
The frame attachment plate 5 is fixed to the stay 4 by, for example, welding. In
addition, the frame attachment plate 5 is fastened to the vehicle body frame using a
bolt. Therefore, the connecting structure 3 is fixed to the vehicle body fi·ame.
25 [0100]
Referring to PIG. 25, a bent p01tion 16 that bends reiinvard in the vehicle
longitudinal direction .L is provided at the tip of the beam attachment surface. 1 Ob of
the bracket 10 on the outside in the vehicle width direction W. The radius of
curvature in the plane of the bent p01tion 16 is preferably 50 to 200 mm. When the
30 radius of curvature is less than 50 mm, since the beam 2 is deformed at a small
curvature, it is difficult to reduce the stress concentrated on the beam 2, and it is
PCT/JP2016/052924
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difficult to obtain the effect of preventing the beam 2 from being deflected. On the
other hand, when the radius of curvature exceeds 200 mm, since the curvature is
large, it is difficult to obtain the effect of the bent p01tion 16, and the stress
concentrates on the beam 2 at the edge of the tip of the beam attachment surface 1 Ob
5 like in the case in which the bent portion 16 is not provided. Here, the beam
attachment surface lOb and the beam 2 are fastened using, for example, a bolt.
Therefore, the beam 2 is fixed to the connecting structure 3.
[0101]
The third reinforcing member 15 is provided to bridge the beam attachment
10 smface 1 Ob of the bracket 10 and the rear surface 4b of the stay 4. In the present
embodiment, the third reinforcing member 15 is a triangular plate member and is
welded to the rear surface 4b (hereinafter referred to as a "reinforcing member
attachment surface") of the stay 4 and the inner surface of the bracket 10. Two third
reinforcing members 15 are ananged along the vertical direction V. In addition, the
15 third reinforcing member 15 is formed to follow the bent portion 16 in the vicinity of
the tip of the beam attachment smface 1 Ob on the outside in the vehicle width
direction W. That is, the shape of the tip of the third reinforcing member 15 on the
outside in the vehicle width direction W has a radius of curvature comparable to a
radius of curvature R of the bent portion 16.
20 [0102]
The underrun protector 1 according to the present embodiment is configured
as described above. In such a configuration, as shown in FIG. 26, when a load is
input to the beam 2, the beam 2 is bent and deformed along a curved part of the bent
p01tion 16. Therefore, it is possible to avoid stress locally concentrating on the
25 beam 2 at the tip of the beam attachment surface lOb. Therefore, it is possible to
prevent the cro;s section of the beam 2 from co11apsing due to the bent beam 2
shown in FIG. ?J. As a result, it is possible for the inherent load resistance
performance of the undenun protector 1 to be sufficiently exhibited. Therefore, it is
possible to improve the load resistance performance compared to the underrun
30 protector of the related mt.
[0103]
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While the undemm protector I according to the present embodiment has
been described above, the present invention is not limited thereto. For example, the
shapes of the members of the c01mecting structure 3 connecting the beam 2 and the
vehicle body frame (not shown) are not limited to the examples described in the
5 above embodiment. More specifically, the stay 4 formed in a U-shape in a plan
view may be arranged so that an opening part thereof faces the outside in the vehicle
width direction W. In this case, a flat plate covering the opening pati of the stay 4
or the like may be additionally provided, and the third reinforcing member 15 may be
provided to bridge the beam attachment surface 1 Ob and the flat plate. Altematively,
10 the surface 1 Oa on the vehicle body frame side of the bracket I 0 may be welded in
accordance with the opening part of the stay 4 facing the outside in the vehicle width
direction W, and the third reinforcing member 15 may be provided to bridge the
surface 1 Oa on the vehicle body frame side of the bracket 10 and the beatn
attachment surface 1 Ob.
15 [0104]
In addition, instead of the stay 4, a plate member that extends in the vertical
direction V may be used. In this case, the surface 1 Oa on the frame attachment side
of the bracket 10 may he formed in a U-shape in a plan view, the surface 1 Oa on the
frame attachment side may be welded to the plate member, and the third reinforcing
20 member 15 may be provided to bridge the plate member and the beam attachment
smface 1 Ob.
[0105]
That is, the connecting structure 3 connecting the beam 2 and the vehicle
body frame (not shown) includes a structure main body part (for example, the stay 4)
25 that is provided to extend in the ve1iical direction V, a frame attachment part to which
'the vehick body frame is attached (for example, the.frame attacli>
Next, an undcnun protector 1 according to a fomih embodiment of the
· present invention will be described. The undenun protector I according to the
5
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present embodiment has a configuration in which characteristic components (a
protrusion and a reinforcing member) of the underrun protector 1 according to the
first embodiment to the third embodiment of the present invention are combined.
[0116]
FIG. 32 is a perspective view of a schematic configuration of the underrun
protector 1 according to the fourth embodiment of the present invention. FIG. 33 is
a cross-sectional view of the underrun protector 1 according to the present
embodiment taken along the line XXXIII-XXXIII shown in FIG. 32. FIG. 34 is a
cross-sectional view of the undenun protector 1 according to the present embodiment
10 taken along the line XXXIV-XXXIV shown in FIG. 32. Here, since functions of the
beam 2, the stay 4, the frame attachment plate 5, the bracket 10, the third reinforcing
member 15, and the vehicle body fi·ame 20 which are basic components of the
underrun protector 1 are the same as those in the first embodiment to the third
embodiment of the present invention, description thereof will be omitted.
15 [0117]
As shown in FIG. 32 and FIG. 33, the stay 4 according to the present
embodiment includes the protrusion 6. The protrusion 6 protrudes fi·om the opening
part of the beam 2 inside the beam 2 and is fixed to the first top smface part 2a and
the first bottom surface pal1 2b of the beam 2. Here, as shown in FIG. 33, a cross-
20 sectional shape in a cross-sectional view perpendicular to the vehicle width direction
W of the beam 2 according to the present embodiment may be a T shape unlike the
fust embodiment of the present invention. In such a shape, the stay 4 can be
arranged in contact with each of the first flange pmis 2d of the beam 2. Therefore,
the load transmitted fi·om the first flange pal1 2d to the stay 4 increases. Therefore,
25 the load resistance performance with respect to the load applied at the attachment
position PI on the beam 2 shown in FIG. 2 is improved.
[0118]
In addition, as shown in FIG. 32 and FIG. 34, the first reinforcing member 9
is provided in the opening pati of the beam 2 according to the present embodiment.
30 The first reinforcing member top surface pati 9a and the first reinforcing member
bottom surface part 9b of the first reinforcing member 9, and the first top surface pmi
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2a and the first bottom surface part 2b are bonded respectively by, for example,
welding. In addition, a closed cross section is formed by the beam 2 and the first
reinforcing member 9. Therefore, it is possible to futiher prevent deformation of
the first top surface part 2a and the first bottom surface pmi 2b to the inside of the
5 cross section. Therefore, the load resistance performance with respect to the load
applied to the position P2 lateral to the attachment position of the beam 2 in the
vehicle width direction W shown in FIG. 2 is improved.
[0119]
In addition, as shown in FIG. 32 and FIG. 34, the third reinforcing member
10 15 is provided to bridge the stay attachment surface I Oa and the beam attachment
surface 1 Ob of the bracket 10 according to the present embodiment. In addition, the
bent portion 16 that bends rearward in the vehicle longitudinal direction L is
provided at the tip of the beam attachment surface 1 Ob of the bracket 1 0 on the
outside in the vehicle width direction W. Therefore, when a load is applied at the
15 position P2 lateral to the attachment position of the bemn 2 in the vehicle width
direction W shown in FIG. 2, it is possible to avoid the stress locally concentrating on
the beam 2 at the tip of the beam attachment surface 1 Ob. Therefore, the load
resistance performance with respect to the load applied to the position P2 lateral to
the attachment position of the beam 2 in the vehicle width direction W shown in FIG.
20 2 is improved.
[0120]
The undenun protector 1 according to the present embodiment is configured
as described above. The undenun protector 1 according to the present embodiment
includes the protrusion 6 shown in the first embodiment of the present invention, the
25 first reinforcing member 9 shown in the second embodiment of the present invention,
and the bracket 10 '-and the tlnid reinforcing member 15 shown in- the third
embodiment of the present invention. Therefore, it is possible to improve the load
resistance performance with respect to a load applied at the attachment position P1
on the bemn 2 and a load applied at the position P2 lateral to the attachment position
30 P 1 in the vehicle width direction W shown in FIG. 2. That is, it is possible to
improve the overall load resistance performance of the undenun protector l.
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[0121]
Here, while the components according to the first embodiment to the third
embodiment of the present invention are included in the underrun protector 1 in the
above embodiment, the present invention is not limited thereto. For example, the
5 components in the first embodiment and the second embodiment of the present
invention may be incorporated into the underrun protector l. In addition, the
components shown in the first embodiment and the third embodiment of the present
invention may be incorporated into the underrun protector 1. In addition, the
components shown in the second embodiment and the third embodiment of the
10 present invention may be incorporated into the undenun protector 1. Futihermore,
various modified examples shown in the embodiments can be incorporated into the
undenun protector 1 according to another embodiment. The components shown in
each of the embodiments may be appropriately incorporated into the undenun
protector 1 as long as no structural interference occurs. When these components are
15 combined compositely, it is possible to improve the load resistance performance with
respect to a plurality of load input positions and it is possible to further increase the
improvement rate of the load resistance performance.
[0122]
The underrun protector I according to the fourth-embodiment of the present
20 invention has been described above.
[Examples]
[0123]
(Experimental Example 1)
A load resistance performance evaluation' test was performed using the
25 underrun protector according to the first embodiment of the present invention and an
underrun protector having . a structure of the related mi. The underrun protectur
having a structure of the related ati (Comparative Example 1) had a configuration in
which the protmsion of the stay was removed from the configuration shown in FIG. 4
and the beam had a rectangular cross section. In addition, the undenun protector
30 according to the first embodiment of the present invention was the underrun
protector having the configuration shown in FIG. 4 (Example 1 ). The beam was
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formed of a highly tensile steel with a tensile strength of780 MPa grade, and the stay
was formed of a thick material with a tensile strength of 540 MPa grade.
[0124]
In the load resistance perfmmance evaluation test, an indenter was provided
5 on a beam side surface part at the stay attachment position PI shown in FIG. 2 and a
load was input. FIG. 35 is a diagram for describing a test method in which the load
resistance performance evaluation test was performed using the undenun protector 1
according to Experimental Example 1. The underrun protector 1 shown in FIG. 35
was the undenun protector 1 according to Example 1. As shown in FIG. 35, an
10 indenter 101 was provided at the attachment position Pl on the beam 2 and a load F
was applied to the indenter 101. The load input position was the same in the
underrun protectors according to Example 1 and Comparative Example 1. Then, in
the load resistance performance evaluation test, the indentation amount of the
indenter and the input load were recorded. The load resistance performances of the
15 underrun protectors according to Example 1 and Comparative Example 1 were
evaluated on the basis of the records.
[0125]
FIG. 36 shows a relationship between the indentation amount of the indenter
and the input load in Example 1 and Comparative Example 1. Here, the "load
20 ratio" shown in FIG. 36 represents a ratio between the recorded input load and the
maximum input load obtained in the load resistance performance evaluation test for
Comparative Example 1.
[0126]
As shown in FIG. 36, in Comparative Example 1, the input load gradually
25 increased as the indentation amount of the indenter increased. In addition, in
Compai'ative Exan1ple 1, when the indenter was pushed in to some extent, the input
load was almost constant. On the other hand, in Example 1, in a stage in which the
indentation amount of the indenter was small, the increase in the input load was
significant. In addition, in Example 1, the input load gradually decreased thereafter.
30 [0127]
In the load resistance performance evaluation test, the maximum load ratio ·
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of the underrun protector according to Example 1 with respect to the undenun
protector according to Comparative Example 1 is shown in Table 1.
[0128]
[Table 1]
5 Table 1
Example 1
Comparative
Example 1
[0129]
Structure of underrun protector Maximum
Beam Protrusion load ratio
Hat -shaped cross section Provided 1.71
Rectangular cross section Not provided 1
As shown in Table 1, according to the underrun protector of Example 1, it
was possible to improve the load resistance performance by 70% or more with
respect to the underrun protector according to Comparative Example 1.
10 [0130]
As described above, according to the result of the present experimental
example, the underrun protector according to the first embodiment of the present
invention showed more favorable load resistance performance when a load was
applied at the attachment position of the beam than the underrun protector of the
15 related art.
[0131]
(Experimental Example 2)
Next, the load resistance performance evaluation test was petfonned using
the undenun protector according to the second embodiment of the present invention
20 and the underrun protector having a structure of the related mt. The underrun
protector having a structure of the related mt was the above underrun protector
according to ~omparative Example 1 and the und"rrun protectqr having the
-
configuration shown in FIG. 19 (Comparative Example 2) in which a second
reinforcing member was added to the undenun protector I according to Comparative
25 Example 1. In addition, the underrun protector according to the second
embodiment of the present invention was the undenun protector having the
configuration shown in FIG. ,g (Example 2), the undenun protector in which the first
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reinforcing member was removed fi·om the configuration shown in FIG. 8 (Example
3), the undenun protector having the configuration shown in FIG. 14 (Example 4),
the underrun protector having the configuration shown in FIG. 17 (Example 5), and
the undenun protector having the configuration shown in FIG. 22 (Example 6). The
5 beam was fotmed of a highly tensile steel with a tensile strength of 780 MPa grade.
The stay and the bracket were formed of a thick material with a tensile strength of
540 MPa grade. In addition, the first reinforcing member and the second
reinforcing member were formed of a thick material with a tensile strength of 780
MPagrade.
10 [0132]
In the load resistance performance evaluation test, an indenter was provided
on a beam side surface part at the position P2 lateral to the stay attacluuent position
in the vehicle width direction W shown in FIG. 2, and a load was input. FIG. 37 is a
diagram for describing a test method in which the load resistance performance
15 evaluation test was performed using the undernm protector I according to
Experimental Example 2. The undenun protector 1 shown in FIG. 37 was the
undenun protector 1 according to Example 2. As shown in FIG. 37, an indenter 102
was provided at the position P2 lateral to the attachment position PI on the beam 2 in
the vehicle width direction W, and a load F was applied to the indenter I 02. The
20 load input position was the same in the underrun protectors according to the
examples and the comparative examples. Then, in the load resistance performance
evaluation test, the indentation amount of the indenter and the input load were
recorded. The load resistance performances ofthe underrun protectors according to
the examples and the comparative examples were evaluated on the basis of the
25 records.
[0133]
FIG. 38 shows a relationship between the indentation amount of the indenter
and the input load in Example 2 and Comparative Example 1. Here, the "load
ratio" shown in FIG. 38 represents a ratio between the recorded input load and the
30 maximum input load obtained in the load resistance performance evaluation test for
Comparative Example I.
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[0134]
As shown in FIG. 38, in both Example 2 and Comparative Example I, as the
indenter was pushed in, the input load increased before the indentation amount
reached a certain amount. In addition, in Example 2 and Comparative Example I,
5 the input load gradually decreased thereafter. In this manner, the relationship
between the indentation amount of the indenter and the input load showed a similar
trend in Example 2 and Comparative Example I. On the other hand, the input
maximum load value was significantly larger in Example 2 than in Comparative
Example I.
10 [0135]
Next, the maximum load ratio and the weight ratio of the underTun
protectors according to Example 2, Example 3, Example 4, and Example 5 with
respect to the undernm protector according to Comparative Example I are shown in
Table 2.
15 [0136]
[Table 2]
Table 2
Structure of underrun protector
Shape of beam Provision of Maximum Weight
Beam attaclunent part reinforcing load ratio ratio
of bracket member/shape
Example2
Hat-shaped
Flat plate
Provided
cross section !flat plate 1.37 1.32
Example 3
Hat-shaped
Flat plate Not provided 1.05 0.92 cross section
Example4
Hat-shaped
Flat plate
Provided
2.03 1.32 cross section /U-shape
Example 5 Hat-shaped Hat-shaped
cross section cross section Not provided 1.16 0.92
Cowparative Rectangular --,,
Example I cross section
Flat plate Not provided I I
.
[0137]
As shown in Table 2, according to the underrun protector of Example 2, it
20 was possible to improve the load resistance performance by 30%. or more with
respect to the undenun protector according to Comparative Example I. In addition,
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according to the underrun protector of Example 3, it was possible to improve the load
resistance performance by 5% with respect to the undenun protector according to
Comparative Example 1. Fmthe1more, according to the underrun protector of
Example 3, it was possible to reduce the weight by about 10% with respect to the
5 undenun protector according to Comparative Example 1. That is, according to the
underrun protector of Example 3, it was possible to improve the load resistance
performance while reducing the weight with respect to the underrun protector of the
related art.
10
[0138]
On the other hand, according to the underrun protector of Example 4, it was
possible to improve the load resistance performance by 100% or more with respect to
the underrun protector according to Comparative Example 1. That is, the underrun
protector according to Example 4 had higher load resistance performance than the
underrun protector according to Example 2. Therefore, when the first reinforcing
15 member having a U-shaped cross section was provided inside the beam, it was
possible to improve the load resistance performance.
[0139]
On the other hand, according to the undernm protector of Example 5, it was
possible to improve the load resistance performance by 15% or more with respect to
20 the undenun protector according to Comparative Example l. Furthermore, the
undenun protector according to Example 5 can be reduced in weight by about 10%
with respect to the underrun protector according to Comparative Example 1. In
addition, the underrun protector according to Example 5 had almost the same weight
as the undenun protector according to Example 3. However, the undenun protector
25 according to Example 5 had higher load resistance performance than the underrun
protector according to Example 3. Accordingly, ii could be understood that, when
the shape of the beam attachment part of the bracket was a hat shape in cross section,
the load resistance performance was further improved.
30
[0140]
Next, the maximum load ratio and the weight ratio of the underrun protector
according to Example 6 with respect to the underrun protector according to
49/64
Comparative Example 2 are shown in Table 3.
[0141]
[Table 3]
Table 3
Stmcture of underrun protector
Shape of beam Shape of
Beam attachment reinforcing
part of bracket member
Example6
Hat-shaped Hat-shaped Hat-shaped
cross section cross section cross section
Comparative Rectangular
Flat plate
Hat-shaped
Example2 cross section cross section
5 [0142]
PCT/JP2016/052924
Maximum Weight
load ratio ratio
1.04 0.82
1 1
According to the undenun protector of Example 6, it was possible to
improve the load resistance performance by 4% with respect to the underrun
protector according to Comparative Example 2. Furthermore, according to the
underrun protector of Example 6, it was possible to t·educe the weight by about 20%
10 with respect to the underrun protector according to Comparative Example 2. That
is, when the second reinforcing member and the bracket had a hat-shaped cross
section, and were provided to support the beam and the side surface part of the
bracket, it was possible to improve the load resistance performance while reducing
the weight with respect to the underrun protector of the related att.
15 [0143]
As described above, according to the result of the present experimental
example, the undenun protector according to the second embodiment of the present
invention showed more favorable load resistance performance than the underrun
protector of the related att when a load was applied at a position lateral to the
20 attachment position of the beam in the vehicle, width direction W.
[0144]
(Experimental Example 3)
Next, the load resistance performance evaluation test was performed using
the underrun protector according to the third embodiment of the present invention
25 and the undenun. protector having a structure of the related art. The underrun
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protector according to the third embodiment of the present invention was the
underrun protector having the configuration shown in FIG. 24 (Example 7), and the
bent pmiion was provided at the tip of the beam attachment sutface on the outside in
the vehicle width direction W. On the other hand, the undenun protector having a
5 structure of the related ati was the underrun protector (Comparative Example 3) in
which the bent potiion at the tip of the beam attachment surface on the outside in the
vehicle width direction W was removed from the underrun protector shown in FIG.
24. The beam was formed of a highly tensile steel with a tensile strength of 780
MPa grade. The stay and the bracket were formed of a thick material with a tensile
10 strength of 540 MPa grade. In addition, a third reinforcing member provided to
bridge the structute main body part and the beam attachment surface in a plan view
was formed of a thick material with a tensile strength of 540 MPa grade. In
addition, the radius of curvature of the bent portion according to Example 9 was 100
mm, and LdLz was 0.6.
15 [0145]
In the load resistance performance evaluation test, in the same manner as in
Experimental Example 2, an indenter was provided on a beam side surface patt at the
position P2 lateral to the stay attachment position in the vehicle width direction W
shown in FIG. 2, and a load was input. The load input position was the same in the
20 undenun protectors according to the examples and the comparative examples.
Then, in the load resistance performance evaluation test, the indentation amount of
the indenter and the input load were recorded. The load resistance performances of
the undenun protectors according to the examples and the comparative examples
were evaluated on the basis of the records.
25 [0146]
FIG. 39 shows a relationship b<.:tween the indentation amount of the indenter
and the input load in Example 7 and Comparative Example 3. As shown in FIG. 39,
the maximum input load of the underrun protector according to Example 7 was larger
than the maximum input load of the underrun protector according to Comparative
30 Example 3. That is, when the bent portion was provided at the tip of the beam
attachment surface, it was possible to improve the load resistance performance of the
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underrun protector.
[0147]
(Experimental Example 4)
Next, in underrun protectors having different structures, an influence of a
5 difference in the structure on load resistance petformance was evaluated. Three
types of structure of the underrun protector were used in the present example, a
structure A in which the bent portion was provided at the tip of the beam attachment
surface on the outside in the vehicle width direction W, a structure B in which the
reinforcing plate shown in FIG. 27 was added to the structure A, and a structure C in
10 which the partition member shown in FIG. 31 was added to the structure A. Here,
the shape of the third reinforcing member was the same in the structures. In
addition, for the structure A, two lengths L1 of the third reinforcing member shown in
FIG. 2S in the vehicle longitudinal direction L were provided. In addition, for the
structures A to C, three radii of curvature of the bent portion were provided. In
15 Example 8 to Example 19, the load resistance performance evaluation test was
performed. Since test conditions were the same as those in Experimental Example
3, description thereof will be omitted.
[0148]
--Parameters of the structures of the underrun protectors according to
20 Example 8 to Example 19 and the maximum load ratio and the weight ratio of the
undenun protectors according to Example 8 to Example 19 with respect to the
underrun protector according to Comparative Example 3 are shown in Table 4.
[0149]
[Table 4]
25 Table 4
Example 8
Example 9
Example 10
Example 11
Example 12
Structu;e of undenun protector
Radius of Structure Ll/L2
curvature [mm]
so A 0.6
100 A 0.6
200 A 0.6
so B 0.6
100 B 0.6
Maximum
load ratio
1.02
1.02
1.02
!.OS
l.OS
·---
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Example 13 200 B 0.6 1.05
Example 14 50 c 0.6 1.09
Example 15 100 c 0.6 1.1
Example 16 200 c 0.6 1.13
Example 17 50 A 1 1.09
Example 18 100 A 1 1.11
Example 19 200 A 1 1.12
[0150]
As shown in Table 4, the structure B had higher load resistance perf01mance
than the structure A. In addition, the structury C had higher load resistance
performance than the structure B. That is, according to the present example, it
5 could be understood that, when the reinforcing plate was provided inside the closed
cross section part of the connecting structure in addition to the provision of the bent
portion at the tip of the beam attachment surface of the connecting structure, the load
resistance performance was improved. In addition, it could be understood that,
when the partition member was provided inside the closed cross section part of the
10 connecting structure instead of the reinforcing plate, the load resistance performance
was further improved. Here, it was considered that, when both the structure B and
the structure C were applied to the underrun protector, the load resistance
performance was further improved.
15
[0151]
In addition, as shown in Table 4, in the structure C, it could be understood
that the load resistance performance was further improved as the radius of curvature
of the bent portion increased. That is, when out -of-plane defommtion of the closed
cross section part due to the input load was effectively prevented as in the structure C,
it was possible to fu1ther improve the load resistance performance by increasing the
20 radius of curvature of the bent portion.
[0152]
In addition, as shown in Exan1ple 8 to Example 10 and Example 17 to
Example 19 in Table 4, it could be understood that, when the value of LdL2 was
large, the load resistance performance was improved as the radius of curvature of the
25 bent portion increased.
[0153]
i / .
.
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In order to additionally verify the effect of the length L1 of the third
reinforcing member in the vehicle longitudinal direction L, the impact resistance
performance evaluation test was performed while changing L,. FIG. 40 is a graph
showing a relationship between a ratio between the length L1 and the length L2 of the
5 reinforcing member attachment surface in the vehicle longitudinal direction L and
the maximum load ratio with respect to the undenun protector of the related att.
Here, the radius of curvature of the bent portion was 200 mm.
[0154]
As shown in FIG. 40, when Lt!L2 was 0.8 or more, the load resistance
10 performance was significantly improved. Therefore, the third reinforcing member
is preferably provided to satisfy LtfL2~0.8. Such findings were obtained by the
inventors for the first time.
[0155]
As described above, according to the results of Experimental Example 3 and
15 Experimental Example 4, the underrun protector according to the third embodiment
of the present invention showed more favorable load resistance performance than the
underrun protector of the related art when a load was applied at a position lateral to
the attachment position of the beam in the vehicle width direction W.
[0156]
20 (Experimental Example 5)
Next, the load resistance performance evaluation test was performed using
the undenun protector according to the fourth embodiment of the present invention
and the undenun protector having a structure of the related art. The underrun
protector having a structure of the related art was the above undenun protector
25 according to Comparative Example 1. In addition, the undenun protector according
to the fourth embodiment of the present invention was the underrun protectm' having
the configuration shown in FIG. 32 (Example 20). The beam was formed of a
highly tensile steel with a tensile strength of 780 MPa grade. The stay and the
bracket were formed of a thick material with a tensile strength of 540 MPa grade.
30 In addition, the first reinforcing member was formed of a thick material with a tensile
strength of 780 MPa grade. In addition, the third reinforcing member was formed
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of a thick material with a tensile strength of 540 MPa grade.
[0157]
In the load resistance performance evaluation test, in the same manner as in
Experimental Example 2 to Experimental Example 4, an indenter was provided on a
5 beam side surface part at the position P2 lateral to the stay attachment position in the
vehicle width direction W shown in FIG 2, and a load was input. The load input
position was the same in the underrun protectors according to Example 20 and
Comparative Example 1. Then, in the load resistance performance evaluation test,
the indentation amount of the indenter and the input load were recorded. The load
10 resistance performances of the underrun protectors according to Example 20 and
Comparative Example 1 were evaluated on the basis of the records. Here, the
underrun protector according to Example 20 had the same configuration as the
undetrun protector according to Example 1. That is, the load resistance
performance obtained when a load was input at the stay attachment position P1
15 shown in FIG 2 was considered to have the same result as the evaluation result in
Experimental Example 1. Therefore, the load resistance performance evaluation
test for the underrun protector according to the present example will not be described
here.
20
[0158]
The maximum load ratio of the underrun protector according to Example 20
with respect to the underrun protector according to Comparative Example 1 is shown
in Table 5.
[0159]
[Table 5]
25 Table 5
'Y f' Structure of undenun pro tecto!'
Provision of fust
Provision of Maximum
Beam Protmsion reinforcing
third
load ratio
reinforcing
member/shape
member
Hat-
Provided
Example 20 shaped · Provided
/U-shapc
Provided 2.37
cross
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section
Comparative
Rectangul
Not
Example 1
ar cross provided
Not provided Not provided 1
section
[0160]
According to the underrun protector according to Example 20, it was
possible to improve the load resistance performance by 130% or more with respect to
the undernm protector according to Comparative Example 1. Therefore, when the
5 first reinforcing member having a U-shaped cross section and the third reinforcing
member provided to bridge the beam attachment surface and the reinforcing member
attachment surface were applied to the underrun protector compositely, it was
possible to significantly improve the load resistance performance.
10
[0161]
As described above, according to the result of the present experimental
example, the underrun protector according to the fomih embodiment of the present
invention showed significantly favorable load resistance performance with respect to
the underrun protector of the related art when a load was applied at the position
lateral to the attachment position of the beam iu the vehicle width direction W.
15 [0162]
The preferred embodiment(s) of the present invention has/have been
described above with reference to the accompanying drawings, whilst the present
invention is not limited to the above examples. A person skilled in the art may find
various alterations and modifications within the scope of the appended claims, and it
20 should be understood that they will naturally come under the technical scope of the
present invention.

Claim 1
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CLAIMS
An end stmcture of a vehicle, comprising:
a beam that extends in a vehicle width direction; and
a connecting stmcture that connects the beam to a vehicle body fi·ame,
wherein, in a cross-sectional view perpendicular to the vehicle width
direction, the beam includes
a first top surface patt and a first bottom surface pmt which face each other,
a first side smface pati that connects one ends of the first top surface pmt
10 and the first bottom surface pati, and
first flange parts that are formed to protmde vetiically outwardly at the other
ends of the first top surface pati and the first bottom surface pati, and
the beam is fixed to the connecting stmcture by at least one of bonding of a
protmsion that is provided in the connecting stmcture, protrudes inside the beam, and
15 is arranged inside the beam to the first top surface pati and the first bottom surface
pati and bonding of a beam attachment member provided in the connecting stmcture to the first flange parts.Claim 2
The end structure of a vehicle according to claim 1,
wherein, in a case where the protmsion is provided 111 the connecting
stmcture, a protruding side surface part which faces the first side surface patt is
formed in the protrusion.
25 Claim 3
30
The end stmcture of a ''ehicle accot'Jing to claim 1,
wherein, in a case where the beam .attachment member is provided in the
c01mecting structure and the beam attachment member is fixed to the first flange
pmts,
in a cross-sectional view perpendicular to the vehicle width direction, the
beam attachment member includes a second top surface pmt and a second bottom surface part which face each
other,
a second side surface patt that connects one ends of the second top surface
pmt and the second bottom surface patt, and
second flange parts formed to protrude vertically outwardly at the other ends
of the second top surface part and the second bottom surface pmt, and
the first flange parts and the second flange parts are fixed.
Claim 4
The end structure of a vehicle according to claim 3,
wherein the second side smface patt is positioned on a vehicle interior side
in a vehicle longitudinal direction with respect to the first flange parts.
Claim 5
The end structure of a vehicle according to any one of claims 1 to 4,
wherein, in a case where the beam attachment member is provided in the
corutecting structure and the beam attachment member is fixed to the first flange
patts,
a first reinforcing member is provided in a region of an opening part of the
20 beam that faces at least the connecting structure in the vehicle width direction, and
25
30
a closed cross section is fonned by the beam and the first reinforcing
member in a cross-sectional view perpendicular to the vehicle width direction.surface part, and
the first reinforcing member is arranged inside the beam, the first top
surface part and the first reinforcing member top surface patt are fixed, and the first
bottom surface part and the first reinforcing member bottom surface pmt are fixed.
Claim 7
The end structure of a vehicle according to claim 6,
wherein, in the first reinforcing member side surface part, a convex pmt that
protrudes to a vehicle interior side in a vehicle longitudinal direction with respect to
10 the fiist flange pmts is formed.
Claim 8
The end structure of a vehicle according to claim 7,
wherein at least a part of the first reinforcing member side surface part is in
15 contact with the connecting structure.
Claim 9
The end structure of a vehicle according to claim 3 or 4,
· · wherein a second reinforcing member is provided in a region of an opening
20 part of the beam that faces at least the beam attachment member,
25
in a cross-sectional view perpendicular to the vehicle width direction, the
second reinforcing member includes
a second reinforcing member top surface part and a second reinforcing
member bottom surface part which face each other,
a second reinforcing member side surface part that cmmects one ends of the
second reinforcing· member tov surface pmt and the second reinforcing ·member
bottom surface patt, and
second reinforcing member flange parts formed to protrude vertically
outwardly at the other ends of the second reinforcing member top surface part and
30 the second reinforcing member bottom surface pmt,
the second reinforcing member is arranged inside the beam,
5
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the second reinforcing member flange parts are fixed to the first side surface
part, and
the second reinforcing member side smface pmt is in contact with the beam
attachment member.
Claim 10
The end structure of a vehicle according to any one of claims 1 to 9,
wherein, in a case where the beam attachment member is provided in the
connecting stmcture and the beam attachment member is fixed to the fn·st flange
10 parts,
the connecting structure further includes a structure main body part that is
provided to extend in the vertical direction,
the beam attachment member includes
a beam attachment surface to which the beam is attached and which
15 includes a bent portion that bends toward a vehicle interior side in a vehicle
longitudinal direction at an end on the outside in the vehicle width direction, and
20
25
a main body connecting smface which includes a surface perpendicular to
the beam attachment surface in a plan view and is attached to the structure main body
part, and
at least one third reinforcing member is additionally provided to bridge the
structure main body patt and the beam attachment surface in a plan view.
Claim 11
The end structure of a vehicle according to claim I 0,
wherein the bent portion has a radius of curvature of 50 to 200 mm.
Claim 12
The end structure of a vehicle according to claim I 0 or 11,
wherein the third reinforcing member is provided such that a ratio L1/L2 of a
30 length L1 of the third reinforcing member in the vehicle longitudinal direction to a
length L2 of a surface of the stmcture main body part to which the third reinforcing
5
10
15
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member is attached in the vehicle longitudinal direction is 0.8 or more.
Claim 13
The end structure of a vehicle according to any one of claims 10 to 12,
wherein the structure main body part has a U-shaped cross section in which
an opening part is provided in the vehicle width direction in a plan view, and
a closed cross section patt whose horizontal cross section shape formed by
the structure main body part and the main body connecting surface is a closed cross
section is further provided.
Claim 14
The end structure of a vehicle according to claim 13,
wherein, in a case where a plurality of third reinforcing members are
provided in the vertical direction,
inside the closed cross section part, a reinforcing plate arranged in
accordance with a position of a rear side tip, among tips of the third reinforcing
member, in the vehicle longitudinal direction is provided, and
the reinforcing plate has a shape that extends to the rear side tip of the third
reinforcing member positioned on the uppermost side from the rear side tip of the
20 third reinforcing member positioned on the lowermost side among the plurality of
25
third reinforcing members.
Claim 15
The end structure of a vehicle according to claim 13 or 14,
wherein a partition member is provided to fill a space inside the closed cross
section part in a horizont;li cross-sectional view of the closed cross section iJatt, and
the partition member is arranged in accordance with an installation height of
at least one of the third reinforcing members.
30 Claim 16
The end structure of a vehicle according to any one of claims 1 to 15,
5
10
15
20
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wherein the end structure of the vehicle is an underrun protector.
Claim 17
An end structure of a vehicle, comprising:
a beam that extends in a vehicle width direction and a connecting structure
that connects the beam and a vehicle body frame,
and
wherein the connecting structure includes
a structure main body part that is provided to extend in a vertical direction,
a beam attachment member to which the beam is attached,
the beam attachment member includes
a beam attachment surface to which the beam is attached and which
includes a bent portion that bends toward a vehicle interior side in a vehicle
longitudinal direction at an end on the outside in the vehicle width direction, and
a main body connecting surface which includes a surface perpendicular to
the beam attachment surface in a plan view and is attached to the structure main body
part, and
at least one reinforcing member is additionally provided to bridge the
structure main body part and the beam attachment surface in a plan view.