DESCRIPTION
TITLE OF INVENTION: BRAKE LINING FOR RAILWAY VEHICLE, AND
DISC BRAKE EQUIPPED WITH THE SAME
TECHNICAL FIELD
Eoooll
The present invention relates to a disc brake using a floating brake
caliper as a braking device for a railway vehicle, and particularly relates to
a brake lining for a railway vehicle pressed against a frictional surface of a
brake disc fixed to a wheel or an axle and to a disc brake for a railway
vehicle equipped with the brake lining.
BACKGROUND ART
[00021
Following speeding up and growing in size, a disc brake is
frequently used as a braking device for a land transportation vehicle such as
a railway vehicle, an automobile or a motorcycle. The disc brake is a
device that produces a braking force by friction derived from the sliding
contact between a brake disc (hereinafter, also simply "disc") and a brake
lining (hereinafter, also simply "lining"). In a case of the disc brake for the
railway vehicle, the braking force is generated by pressing the lining, by a
brake caliper (hereinafter, also simply "caliper"), against a frictional surface
of the disc which has been mounted and fixed to a wheel or an axle. In this
manner, the rotation of the wheel or the axle is slowed or stopped so that the
speed of the vehicle is controlled.
Eooo31
Normally, the friction member of the lining is gradually worn away
as a result of repetition of braking. However, if the friction member is
partially worn away, braking performance becomes unstable. Therefore, to
prevent the partial wear of the friction member, it is preferable that a
pressing load is uniformly applied to the entire regions of the friction
member during braking.
[0004]
Furthermore, during braking, temperatures of the frictional
surfaces of the lining and the disc increase by frictional heat. This
temperature increase tends to be more conspicuous in conditions in which a
braking load increases, to be specific, in conditions in which the traveling
speed of the vehicle is high or in which the vehicle weight is heavy. In the
actual traveling, it is desired to prevent thermal damages on the Lining and
the disc and to improve the durability of the lining and the disc. To this
end, it is necessary to make the contact between the lining and the disc as
uniform as possible and to reduce the frictional heat generated as a result of
the contact during braking.
[00051
The caliper includes caliper arms extending to stride over the disc
and the caliper arms hold linings, respectively. The calipers are mainly
classified into a floating type and an opposed type, depending on the
arrangement configuration of a drive source, for example, pistons or
diaphragms, for pressing the lining against the disc. In a case of the
floating type, the pressing drive source such as the pistons or diaphragms is
provided only on one of the caliper arms each holding the lining. In a case
of the opposed type, the pressing drive sources such as pistons or
diaphragms are provided on both caliper arms, respectively.
[0006]
For the railway vehicle, the disc brake using the floating caliper is
often used. The disc brake will be described while referring only to the disc
brake of the floating type.
[00071
FIG. 1 shows an example of a configuration of a conventional disc
brake for a railway vehicle, illustrating one side thereof on which the
pressing drive source is not provided. In the figure, FIG. l(a) is a plan
view in which a lining is viewed from a front surface side, FIG. l(b) is a plan
view in which the lining is viewed from a back surface side, FIG. l(c) is an
enlarged cross-sectional view taken along A-A of FIG. l(a), and FIG. l(d) is
a cross-sectional view in a state in which the lining shown in FIG. l(c) is
detached from a caliper arm.
[ooosl
A conventional lining (hereinafter, "conventional type lining") 12
shown in FIG. 1 is configured to include a friction member 3 that faces a
fkictional surface l a of a disc 1, a base plate 14 having a h e d thickness and
holding the fiction member 3 on a front surface 14a, and a guide plate 15
fixedly provided at the center of a back surface 14b of the base plate 14. In
FIG. 1, it is shown that a plurality of small-block-shaped friction members 3
are arranged, i.e., pairs of friction members 3 are arranged in a radial
direction of the disc 1 and seven friction members 3 are arranged in a
circumferential direction of the disc 1, that is, 14 friction members 3 are
arranged in all. The friction members 3 are attached to the base plate 14
by rivets 6, respectively. A spring member may be arranged between the
friction members 3 and the base plate 14.
[00091
The conventional type lining 12 is mounted to a lining holder
(hereinafter, also simply "holder") incorporated into each caliper arm, and
set in a state in which a frictional surface 3a of each friction member 3 faces
the frictional surface la of the disc 1 in parallel. As shown in FIGS. l(c) and l(d), on the side on which the pressing drive source such as pistons is
not provided (hereinafter, also "non-pressing-drive-source side"), a holder 8
is integrally incorporated into the caliper arm 7, and a concave portion 8b
that accommodates therein the guide plate 15 of the lining 12 is formed in
this holder 8. The guide plate 15 of the lining 12 is set in a state in which
upper and lower edges 15b and 15c of the guide plate 15 are engaged with
upper and lower edges 8d and 8e of the concave portion 8b of the holder 8, respectively while a back surface (a surface that is on a back surface side
relative to the lining) 15a closely contacts a bottom surface (a surface that is
on a front surface side relative to the lining) 8c of the,concave portion 8b of
the holder 8. Such strong coupling of the guide plate 15 with the concave
portion 8b of the holder 8 enables the non-pressing-drive-source side lining
12 to be strongly held to the holder 8 directly incorporated into the caliper
arm 7.
[00101
Meanwhile, on the side on which the pressing drive source is
provided (hereinafter, also "pressing-drive-source side"), a holder is
attached to the pressing drive source, and a concave portion similar to that
on the non-pressing-drive-source side is formed in this holder. Similarly to
the non-pressing-drive-source side, the strong coupling of the guide plate
with the concave portion of the holder enables the pressing-drive-source
side lining 12 to be strongly held to the holder incorporated into the caliper
arm via the pressing drive source.
[00111
In the conventional disc brake configured as described above,
during braking, on the pressing-drive-source side, the pressing drive source
is actuated, whereby a pressing force is loaded onto the lining 12 from the
pressing drive source and the lining 12 is pressed against the disc. On the
other hand, as shown in FIG. l(c), on the non-pressing-drive-source side, a
reaction force to the pressing force on the pressing-drive-source side is
applied to the caliper arm 7, and the caliper arm 7 slidably moves toward
the disc 1 (see a white arrow in FIG. l(c)) and the lining 12 is pressed
against the disc 1. At this time, on both the pressing-drive-source side and
the non-pressing-drive-source side, the pressing force loaded onto the lining
12 directly acts on the guide plate 15 of the lining 12 via the holder 8 of the
caliper arm 7. That is, the pressing force loaded onto the lining 12 does not
directly act on the base plate 14 of the lining 12 but intensively acts on the
guide plate 15 of the lining 12 because of a structure of a mounted portion of
the lining 12 to the caliper arm 7.
Loo 121
In the case of the disc brake using the floating caliper, on the
non-pressing-drive-source side, a phenomenon occurs that the caliper arm 7
is bent to open as the lining 12 is pressed against the disc 1 during braking.
Owing to this, the friction member 3 on the non-pressing-drive-source side
exhibits a tendency that a higher load acts on a region corresponding to an
outer circumferential side of the disc 1 (hereinafter, also "outer
circumferential-side region") than on a region corresponding to an inner
circumferential side of the disc 1 (hereinafter, also "inner
circumferential-side region"). This particularly accelerates the wear of the
outer circumferential-side region of the f'ction member 3 and the partial
wear of the friction member 3, and even probably accelerates the partial
wear of the disc 1.
[00131
To tackle these problems, various types of disc brakes with
improved structures have been proposed recently with views of making
uniform the pressure of the contact surfaces between the lining and the disc
during braking.
[00141
For example, each of Patent Literatures 1 and 2 discloses a disc
brake configured as follows. In anticipation that the caliper arm is bent to
open on the side on which pistons serving as the pressing drive force are not
provided during braking, the friction member is mounted-to the holder of
the caliper arm in a state in which the frictional surface of the friction
member is inclined at a predetermined angle with respect to the frictional
surface of the disc. In a case of Patent Literature 1, by changing the shape
of the holder without changing the structure of the lining, the frictional
surface of the friction member is inclined with respect to the frictional
surface of the disc. In a case of Patent Literature 2, by changing the
thickness of the friction member of the lining without changing the
structure of the holder, the frictional surface of the friction member is
inclined with respect to the frictional surface of the disc. According to such
a disc brake, during braking, the contacts of the friction member with the
disc starts from the inner circumferential-side region, and the frictional
surface of the friction member contacts the fi-ictional surface of the disc
substantially in a parallel state by the bending of the caliper arm to follow
the applied load. As a result, the surface pressure is made constant over
the entire regions of the friction member.
roo151
However, in the disc brakes described in Patent Literatures 1 and 2,
at the beginning of braking, the inner circumferential-side region of the
friction member contacts the disc but the outer circumferential-side region
thereof does not contact the disc. Owing to this, the partial wear of the
friction member still probably occurs.
CITATION LIST
PATENT LITERATURE
LOO 161
Patent Literature 1: Japanese Patent Application Publication No.
2008-281156
Patent Literature 2: Japanese Patent Application Publication No.
2008-267527
SUMMARY OF INVENTION
TECHNICAL PROBLEM
[00171
The present invention has been made in light of the
aforementioned problems, and an object of the present invention is to
provide a brake lining for a railway vehicle and a disc brake for a railway
vehicle equipped with this brake lining capable of contacting a fxction
member with a brake disc over entire regions from the beginning of braking
on a non-pressing-drive-source side of the 'disc brake using a floating brake
caliper, uniformly applying a pressing load onto the entire regions of the
friction member during braking, and eventually improving durability.
SOLUTION TO PROBLEM
[0018]
In order to achieve the above object, the gist of the present
invention lies in a brake lining for a railway vehicle shown in (I) below and
a disc brake for a railway vehicle shown in (11) below.
Loo 191
(I) A disc brake for a railway vehicle using a floating brake caliper,
the floating brake caliper including caliper arms each striding over a brake
disc fixed to a wheel or an axle of the railway vehicle; a brake lining held by
each of the caliper arms; and a pressing drive source provided only on one of
the caliper arms each holding the brake lining, characterized in that
the brake lining held by the caliper arm on a side on which the
pressing drive source is not provided, the brake lining comprises:
a friction member facing a frictional surface of the brake disc; a
base plate holding the friction member on a front surface; and a guide plate
fixedly provided at center of a back surface of the base plate, and
accommodated in a concave portion of the caliper arm,
on the side on which the pressing drive source is not provided, the
front surface of the base plate is in parallel to a frictional surface of the
friction member, a thickness of the base plate is larger on a side
corresponding to an inner circumferential side of the brake disc than on a
side corresponding to an outer circumferential side of the brake disc, and a
thickness of the guide plate is smaller than a depth of the concave portion of
the caliper arm, and
on the side on which the pressing drive source is not provided, in a
state in which the frictional surface of the friction member faces the
frictional surface of the brake disc in parallel, the guide plate is fitted, with
play, into the concave portion of the caliper arm. .
Lo0201
It is preferable that in the brake lining described in (I) above, the
back surface of the base plate is an inclined surface inclined with respect to
the front surface.
1002 11
It is preferable that in these brake linings, the thickness of the
base plate is larger on the side corresponding to the inner circumferential
side of the brake disc by 0.25 mm to 2.0 mm than on the side corresponding
to the outer circumferential side of the brake disc.
Lo0221
In these brake linings, in a state in which the guide plate is fitted,
with play, into the concave portion of the caliper arm, a cavity is present
between the back surface of the guide plate and the concave portion of the
holder and a cavity is present between the back surface of the base plate
and the caliper arm.
LO0231
(11) A disc brake for a railway vehicle characterized by including
the brake lining according to any one of claims 1 to 4.
ADVANTAGEOUS EFFECTS OF INVENTION
100241
In the brake lining and the disc brake for the railway vehicle
according to the present invention, since the frictional surface of each
friction member is arranged to face the frictional surface of the disc in
parallel on the non-pressing- drive-source side, the friction member can
contact the disc over the entire regions horn the beginning of braking.
Besides, the lining is movably attached to the caliper arm since the guide
plate is fitted, with play, into the concave portion of the caliper arm, and the
thickness of the guide plate is smaller than the depth of the concave portion
of the caliper arm. Therefore, during braking, on the
non-pressing-drive-source side, the base plate contacts the caliper arm in a
wide range to follow the bending of the caliper arm. The pressing force
loaded onto the lining thereby does not act on the guide plate but directly
acts on the base plate, and it is thereby possible to uniformly apply the
pressing load to the entire regions of the friction member. As a
consequence, it is possible to prevent the partial wear of the friction
members and improve the durability. ~
BRIEF DESCRIPTION OF DRAWINGS
Lo0251
FIG. 1 shows an example of a configuration of a conventional disc
brake for a railway vehicle, illustrating one side thereof on which the
pressing drive source is not provided;
FIG. 2 shows an example of a configuration of a disc brake for a
railway vehicle according to the present invention, illustrating one side
thereof on which the pressing drive source is not provided; and
FIG. 3 shows a modification of a configuration of the disc brake for
a railway vehicle according to the present invention, illustrating one side
thereof on which the pressing drive source is not provided.
DESCRIPTION OF EMBODIMENTS
[00261
Hereinafter, embodiments of a brake lining and a disc brake for a
railway vehicle according to the present invention will be described in
detail. '
Lo0271
, FIG. 2 shows an example of a configuration of a disc brake for a
railway vehicle according to the present invention, illustrating one side
thereof on which the pressing drive source is not provided. In the figure,
FIG. 2(a) is a cross-sectional view, and FIG. 2(b) is a cross-sectional view in
a state in which a lining shown in FIG. 2(a) is detached from a caliper arm.
Note that FIGS. 2(a) to 2(b) correspond to FIGS. l(c) and l(d), respectively.
As for a non-pressing-drive-source side of the disc brake according to the
present invention, a configuration in which the lining is viewed £rom a front
surface side is the same as that shown in FIG. l(a) and a configuration in
which the lining is viewed from a back surface side is the same as that
shown in FIG. l(b).
[00281
The disc brake according to the present invention includes a brake
disc 1, a brake lining, and a brake caliper to which this lining is mounted.
The disc 1, which is of a doughnut disc shape, is fixed to a wheel or an axle
(not shown) by bolts or the like, and strongly fastened thereto.
[00291
The caliper includes caliper arms extending to stride over the disc 1
and the caliper arms hold linings, respectively. Since the caliper used in
the present invention is a floating caliper, a pressing drive source such as
pistons is provided only on one caliper arm that is not shown in FIGS. 2(d
to 2(b) out of the caliper arms each holding the lining. The pressing drive
source is actuated by hydraulic pressure or air pressure.
[00301
On a pressing-drive-source side, a lining holder is attached to the
pressing drive source incorporated in the caliper arm, and this holder
strongly holds the same lining as the conventional type lining 12 shown in
FIG. 1 in.a similar manner as a conventional manner. On the other hand,
as shown in FIG. 2(a), on the non-pressing-drive-source side, the lining
holder 8 is integrally incorporated into the caliper arm 7 similarly to that
shown in FIG. 1. A concave portion 8b accommodating therein a guide
plate 5 of a brake lining 2 according to the present invention, to be described
later, is formed in this holder 8.
1003 11
As shown in FIG. 2, the lining 2 according to the present invention,
which is held by the caliper arm 7 on the non-pressing-drive-source side,
configured to include a friction member 3 that faces a frictional surface l a of
a disc 1, a base plate 4 holding the friction member 3 on a front surface 4a,
and the guide plate 5 fixedly provided at the center of a back surface 4b of
the base plate 4. In FIG. 2, it is shown that a plurality of
small-block-shaped friction members 3 are arranged similarly to FIG. 1.
[00321
Each of the friction members 3, which is made of a sintered copper
material, a resin-based material or the like, has a circular planar shape and
is attached to the base plate 4 by a rivet 6 inserted into a central portion of
the friction member 3. The planar shape of the friction member 3 is not
limited to the circular shape but may be a polygonal shape such as a
quadrangular shape or a hexagonal shape. A spring member may be
provided between the friction members 3 and the base plate 4 for elastically
supporting the friction members 3. As the spring member, a disc spring
can be applied or a plate spring or a coil spring can be also applied.
100331
The front surface 4a of the base plate 4 is in parallel to a frictional
surface 3a of the friction member 3. Furthermore, a thickness of the base
plate 4 is larger on a side corresponding to an inner circumferential side of
the disc 1 (which corresponds to a lower side in FIG. 2, hereinafter, also
simply "inner circumferential side") than on a side corresponding to an
outer circumferential side of the disc 1 (which corresponds to an upper side
in FIG. 2, hereinafter, also simply "outer circumferential side").
100341
From viewpoints of practicality, the back surface 4b of this base
plate 4 is preferably an inclined surface inclined with respect to the front
surface 4a thereof. It is also preferable that a difference between an outer
circumferential side thickness 4to and an inner circumferential side
thickness 4ti of the base plate 4 is within a range from 0.25 mm to 2.0 mm.
More preferably, the difference is from 0.5 mm to 1.0 mm. As described
later, when the difference between the outer circumferential side thickness
and the inner circumferential side thickness of the base plate 4 is smaller
than 0.25 mm, the heavier load tends to act on the outer circumferential
side region of the friction member 3 if the back surface 4b of the base plate 4
contacts the front surface 8a of the holder 8 to follow the bending of the
caliper arm 7 while the friction member 3 contacts the disc 1 during braking.
On the other hand, if the thickness difference exceeds 2.0 mm, a heavier
load conversely tends to act on the inner circumferential side region of the
friction member 3. Such a range of the thickness difference of the base
plate 4 corresponds to 0.1' to l.OO in terms of an inclination angle of the
back surface 4b with respect to the front surface 4a of the base plate 4.
[00351
A thickness 5t of the guide plate 5 is smaller than a depth of the
concave portion 8b of the holder 8 (caliper arm 7). That is, the thickness 5t
of the guide plate 5 is smaller than the thickness of the guide plate 15 of the
conventional type lining 12 shown in FIG. 1. FIG. 2 shows an aspect in
which the thickness 5t of the guide plate 5 is fixed and the back surface 5a
of the guide plate 5 is in parallel to the back surface 4b of the base plate 4.
However, as long as the thickness 5t of the guide plate 5 is smaller than the
depth of the concave portion 8b of the holder 8, the thickness 5t of the guide
plate 5 may be smaller on the inner circumferential side than on the outer
circumferential side so that the back surface 5a of the guide plate 5 can be
made in parallel to the front surface 4a of the base plate 4 as shown in, for
example, FIG. 3.
coo361
In the lining 2 configured as described above, on the
non-pressing-drive-source side, only upper and lower edges 5b and 5c of the
guide plate 5 are engaged with upper and lower edges 8d and 8e of the
concave portion 8b formed in the holder 8 of the caliper arm 7, respectively
in a state in which the frictional surface 3a of each friction member 3 faces
the frictional surface la of the disc 1 in parallel. That is, the guide plate 5
of the lining 2 on the non-pressing-drive-source side is fitted, with play, into
the concave portion 8b of the holder 8 and the lining 2 is thereby movably
attached to the caliper arm 7. In this fitted state with play, a cavity cl is
present between the back surface 5a of the guide plate 5 and the bottom
surface 8c of the concave portion 8b of the holder 8, and a cavity c2 is
present between the back surface 4b of the base plate 4 and the front
surface 8a of the holder 8 (caliper arm 7). The front surface 8a of the
holder 8 is in parallel to the frictional surface l a of the disc 1.
100371
In this way, the disc brake according to the present invention
includes the lining 2 according to the present invention and provided on the
caliper arm 7 on the non-pressing-drive-source side, and the conventional
type lining 12 provided on the caliper arm on the pressing-drive-source side.
During braking, on the pressing-drive-source side, the pressing drive source
is actuated, whereby a pressing force is loaded onto the lining 12 from the
pressing drive source and the lining 12 is pressed against the disc.
[00381
On the other hand, as shown in FIG. 2(a), on the
non-pressing-drive-source side, a reaction force to the pressing force on the
pressing-drive-source side is applied to the caliper arm 7, and the caliper
arm 7 slidably moves toward the disc 1 (see a white arrow in FIG. 2(a)) and
the lining 2 is pressed against the disc 1. At that time, since the frictional
surface 3a of each friction member 3 is arranged to face the frictional
surface la of the disc 1 in parallel, the friction member3 contacts the disc 1
over the entire regions from the i ~ ecrirc umferential side region to the
outer circumferential side region from the beginning of braking. Moreover,
as the friction member 3 is pressed against the disc 1, the reaction force to
the pressing force is applied to the caliper arm 7 and the caliper arm 7 is
bent to open. I
Following this, the cavity c2 between the back surface 4b of the
base plate 4 and the front surface 8a of the holder 8 is closed and the cavity
cl between the back surface 5a of the guide plate 5 and the bottom surface
8c of the concave portion 8b of the holder 8 is made narrower. This is
because the lining 2 is movably attached to the caliper arm 7 since the guide
plate 5 is fitted, with play, into the concave portion 8b of the holder 8, and
the thickness 5t of the guide plate 5 is smaller than the depth of the concave
portion 8b of the holder 8.
[00401
In this way, during braking, on the non-pressing-drive-source side,
the back surface 4b of the base plate 4 contracts the front surface 8a of the
holder 8 in a wide range in a state in which the back surface 5a of the guide
plate 5 does not contact the bottom surface 8c of the concave portion 8b of
the holder 8. Therefore, the pressing force loaded onto the lining 2 does not
act on the guide plate 5 of the lining 2 but directly acts on the base plate 4 of
the lining 2. It is thereby possible to uniformly apply the pressing load to
the entire regions of the friction member 3, that is, to ensure the constant
pressure performance during braking. As a consequence, and also because
of the contact of the friction member 3 with the disc 1 over the entire regions
fiom the beginning of braking as described above, it is possible to prevent
the partial wear of the friction member 3 and improve the durability.
EXAMPLES
[00411
To verrfy the advantageous effects of the present invention, the
following FEM analysis (finite element method analysis) was executed.
100421
[Outline of analysis]
The FEM analysis was executed to evaluate the constant pressure
performance of the fiiction member on the non-pressing-drive-source side
during braking. In the analysis, elastic bodies were used as models of the
caliper arm, the lining, and the disc, and a load corresponding to the
pressing force was applied to the caliper arm. The load acting on the
friction member at this time was evaluated. An analysis target was a disc
brake used for Shinkansen (high-speed railway vehicle).
[00431
[Execution conditions]
Table 1 shows a list of principal execution conditions for the FEM
analysis.
[00441
TABLE 1
100451
In the FEM analysis, the disc brake shown in FIG. 2 was adopted
and the analysis was executed for three aspects of Inventive Examples 1 to
3. In each case, the thickness of the base plate was set larger on the inner
circumferential side than on the outer circumferential side, and the
thickness difference changed among Inventive Examples 1 to 3, that is, the
thickness difference was 1.0 mm in Inventive Example 1, 0.75 mm in
Inventive Example 2, and 0.5 mm in Inventive Example 3. Furthermore,
in each case, the depth of the concave portion of the holder was 7.8 mm, the
thickness of the guide plate was smaller than the depth of the concave
portion of the holder, i.e., 7 mm, and the pressing load was made to directly
act on the base plate during braking.
100461
As common conditions to Inventive Examples 1 to 3, a longitudinal
Classification
Inventive
Example 1
Inventive
Example 2
Inventive
Example 3
Comparative
Example 1
Comparative
Example 2
Comparative
Example 3
Load acting
position
Base plate
Base plate
Base plate
Base plate
Guide plate
Guide plate
Base plate thickness [mm]
Outer
circumferen
tial side
4.0
4.0
4.25
4.5
4.5
4.0
Inner
circumferen
tial side
5.0
4.75
4.75
4.5
4.5
4.75
Thickness
difference
1.0
0.75
0.5
0
0
0.75
length of the base plate (length in the direction 'corresponding to a
circumferential direction of the disc) was 400 mm, and a widthwise length
(length in the direction corresponding to a radial direction of the disc) was
141 mm. For materials of the respective members constituting the lining,
the friction members were made of the sintered copper material and all the
other parts were made of a steel material. The number of the fiiction
members was 14 and the planar shape of each friction member was a
circular shape at a diameter of 45 mm. The disc spring was provided
between the friction members and the base plate as the spring member.
Each fiiction member was- fastened to the base plate by a rivet and the base
plate was fastened to the guide plate by a rivet. The disc was generally
disc-shaped at an inner diameter of 476 mm and an outer diameter of 724
mm.
100471
The FEM analysis was carried out while the pressing forces in -
three conditions of 8 kN, 10 kN, and 12 kN were applied.
[00481
For comparison purposes, the analysis was executed to three
aspects of Comparative Examples 1 to 3. In Comparative Example 1, the
pressing load was made to directly act on the base plate during braking
similarly to Inventive Examples 1 to 3, but the base plate thickness was
constant differently &om Inventive Examples 1 to 3. In Comparative
Example 2, in which the conventional disc brake was assumed, the base
plate thickness was constant and the pressing load was made to act on the
guide plate during braking. In Comparative Example 3, the base plate
thickness was thicker on the inner circumferential side than on the outer
circumferential side similarly to Inventive Examples 1 to 3, but the pressing
force was made to act on the guide plate during braking differently from
Inventive Examples 1 to 3.
[00491
[Evaluation method]
The object of the present invention is to ensure the constant
pressure performance of the friction members on the
non-pressing-drive-source side. Owing to this, as an index corresponding
to the object, a load acting on each of the friction members was extracted by
the FEM analysis, and a standard deviation of each load was calculated
from an extracted load value. If the standard deviation of the load was
smaller, it was evaluated that the constant pressure performance of the
friction member was higher.
[00501
[~esultl
Table 2 shows a result of the FEM analysis.
[00511
TABLE 2
Standard deviation [N] of load acting on fkiction member
Pressing force
Classification
Average of results
8 [kNl 10 [ k ~ l 12 [kNl
of three conditions
of left
Inventive
277.82
Example 1
186.92 111.22 191.98
Inventive
120.90
Example 2
69.67 121.68 104.08
Inventive
82.08
Example 3
175.27 274.73 177.36
Comparative
415.18
Example 1
513.97 610.96 513.36
Comparative
Example 2
375.58 465.91 554.82 465.44
Comparative
383.76
Example 3
464.80 553.49 467.35
, [00521
According to the result shown in Table 2, the standard deviation of
the load acting on the friction member was smaller in Inventive Examples 1
to 3 than in Comparative Examples 1 to 3, and the constant pressure
performance was improved by changing both of the thickness shape of the
base plate and the thickness shape of the guide plate.
INDUSTRLAL APPLICABILILTY
Lo0531
The brake lining and the disc brake for the railway vehicle
according to the present invention can be effectively used for any types of
railway vehicles and particularly useful for the high-speed railway vehicle
the travelling speed of which has a wide range from low speed to high speed.
REFERENCE SIGNS LIST
[00541
1: brake disc
la: frictional surface
2: brake lining
3: friction member
3a: frictional surface
4: base plate
4a: fkont surface
4b: back surface
4to: outer circumferential side thickness
4ti: inner circumferential side thickness
5: guide plate
5t :. thickness
5a: back surface
5b: upper edge
5c: lower edge
6: rivet
7: caliper arm
8: lining holder
8a: front surface
8b: concave portion
8c: bottom surface
8d: upper edge
Be: lower edge
cl: cavity
c2: cavity
12: conventional type brake lining
14: base plate
14a: front surface
14b: back surface
15: guide plate
15a: back surface
15b: upper edge
15c: lower edge
We claim:
1. A disc brake for a railway vehicle using a floating brake caliper, the
floating brake caliper including caliper arms each striding over a brake disc
fixed to a wheel or an axle of the railway vehicle; a brake lining held by each
of the caliper arms; and a pressing drive source provided only on one of the
caliper arms each holding the brake lining, characterized in that
the brake lining held by the caliper arm on a side on which the
pressing drive source is not provided, the brake lining comprises:
a friction member facing a frictional surface of the brake disc; a
base plate holding the friction member on a front surface; and a guide plate
fixedly provided at center of a back surface of the base plate, and
accommodated in a concave portion of the caliper arm,
, on the side on which the pressing drive source is not provided, the
front surface of the base plate is in parallel to a frictional surface of the
friction member, a thickness of the base plate is larger on a side
corresponding to an inner circumferential side of the brake disc than on a
side corresponding to an outer circumferential side of the brake disc, and a
thickness of the guide plate is smaller than a depth of the concave portion of
the caliper arm, and
on the side on which the pressing drive source is not provided, in a
state in which the frictional surface of the friction member faces the
frictional surface of the brake disc in parallel, the guide plate is fitted, with
play, into the concave portion of the caliper arm.
2. The brake lining for a railway vehicle according to claim 1,
characterized in that the back surface of the base plate is an inclined
surface inclined with respect to the &ont surface.
3. The brake lining for a railway vehicle according to claim 1 or 2,
characterized in that the thickness of the base plate is larger on the side
corresponding to the inner circumferential side of the brake disc by 0.25 mm
to 2;0 mm than on the side corresponding to the outer circumferential side
of the brake disc.
4. The brake lining for a railway vehicle according to any one of
claims 1 to 3, characterized in that in a state in which the guide plate is
fitted, with play, into the concave portion of the caliper arm, a cavity is
present between the back surface of the guide plate and the concave portion
of the holder and a cavity is present between the back surface of the base
plate and the caliper arm.
5. A disc brake for a railway vehicle characterized by comprising the
brake lining according to any one of claims 1 to 4.