FLEXIBLE FRICTION PAD AND BRAKE LINING PROVIDED WITH
SUCH A PAD
This invention relates to disc brake linings and
the brackets intended to receive the friction elements.
Brake linings, in particular for railway vehicles,
are generally comprised of at least one base plate used
as a bracket whereon are attached one or several pads,
comprising a friction material block. For example
European patent applications EP1679452 and EP1957820
are known which disclose such brake linings. Outside of
applications for light railway vehicles, the same brake
lining comprises generally several base plates each,
often two per brake disc surface, provided with one or
several pads and mobile in relation to one surface of
the brake disc.
However, the rigidity of the mounting of the pads
on the base element can generate not only premature and
irregular wear of the friction materials . due to
flatness and parallelism defects between the friction
surface of the friction materials and the surface of
the disc during braking, but also intense stress in the
friction materials and in their mounting elements on
the base element. Furthermore, the vibrations induced
during braking . are generally at the origin of
screeching noises that one seeks to minimise, and it is
preferable that the fr-iction elements be spaced in such
a way as to improve the thermographic image of the
lining with regards to the disc during braking, as well
as to facilitate their "cooling and the removal o'f
debris from wear.

One of the purposes of this invention is then to
limit all or a portion of the aforementioned
disadvantages.
To this effect is proposed, according to a first
aspect of the invention, a friction pad intended to be
mounted on a base element bracket, with the pad
comprising a base and at least one first friction
material block, the first friction material block being
attached to at least one portion of said base, the base
and the first friction material block defining a first
plane at the interface thereof, the base of said pad
further having:
- a mounting bracket to which is attached at least
the first friction material block,
- at least one first hooking interface distant
from the mounting bracket in a direction parallel to
the first plane, for directly or indirectly attaching
the pad to the base element bracket, and
- at least one first neck extending parallel to
the first plane, forming a resilient leaf between the
mounting bracket and the first hooking interface, in
order to enable the mounting bracket to accommodate
translational and rotational movements in every
direction.
The neck forming a resilient leaf constitutes a
privileged deformation zone. As such, when the pad is
mounted on the base element, the forces due to the
braking transmitted to the hooking interface are
minimised.
More preferably, the base has a thickness between
0.5 and 5 millimetres, more preferably of 2 millimetres,

in particular on the mounting bracket and on the first
hooking interface. The. neck more preferably has a
thickness at most equal to that of the mounting bracket
or of the first hooking interface in order to be
deformed by minimising the stress transmitted to the
hooking interface.
More preferably, at least the first hooking
interface comprises at least one hooking point. The
hooking point is for example constituted by a hole
which then makes it possible to attach the base of the
pad to the base element, for example by rivets. More
preferably, the first hooking interface comprises at
least two hooking points, for example two holes distant
from one another.
More preferably, at least the first hooking
interface has at least one first relief of the force
and/or torque take-up. Indeed, it is preferable that
the means for attaching the base be dissociated from
the force take-up zones.
According to an example embodiment, this first
relief of the force and/or torque take-up is a housing.
According to another example embodiment, the pad,
more preferably on the mounting bracket, has at least
one first anchoring tab of the friction material block.
According to a preferred embodiment, the pad has
two separate hooking interfaces, distant from the
mounting bracket in a direction parallel to the first
plane, the first hooking interface and the second
hooking interface being connected to the mounting
bracket respectively by a first and a second neck. As
such, the mounting bracket having the friction material

block is able to be displaced according to all
directions and the stress generated transmitted to the
hooking interfaces is minimised.
More preferably, the first and the second hooking
interfaces each include two hooking points separate
from one another. A geometric centre can then be
defined for each hooking point, and in what follows A
and A' shall designate the centres of the hooking
points of the first hooking interface, and B and B'
those of the second hooking interface.
According to an example embodiment, each base has
a first relief and a second relief of the force and/or
torque take-up. The first relief is more preferably-
located between the two hooking points of the first
hooking interface and the second relief is more
preferably located between the two hooking points of
the second hooking interface.
Advantageously, the two hooking points of the
first hooking interface are separated by the same
distance d as the two hooking points of the second
hooking interface. This distance d is the length of the
segment joining the centres of the two hooking points
of the same hooking interface, i.e. [AA']=d and [BB']=d.
More generally there can be an interest in that the
geometry of the hooking points of the first interface
be identical to that of the hooking points of the
second interface, in such a way as to facilitate their
mounting by the same tool.
More preferably, the friction material block of a
pad has a friction surface between 10 and 600 cm2, in
such a way that, according to the number of pads per

lining, a total friction surface of the lining on a
brake disc surface for example between 200 and 600 cm.2
is obtained.
More preferably, at least one of the sides of the
quadrilateral forming the mounting bracket is curved.
As such, the shape of the pads makes it possible to
follow the shape of a base element to which said pads
are intended to be attached.
More preferably, the friction material block is
sintered on the mounting bracket of said base, as is
usual in this type of technology.
According to another aspect of the invention, a
brake lining is also proposed, in one or several
portions, more preferably with two symmetrical portions,
each portion comprising:
- a base element, having a front surface, and a
dorsal surface on the side of which can be attached a
dovetail rail,
- at least one first friction pad such as defined
hereinabove, attached to the side of the front surface
of the base element.
More preferably, the base element of each portion
of the brake lining comprises at least one mounting
point, for example a bore, able to cooperate with a
hooking point of a hooking interface of the first pad.
For example, the bore is able to receive a rivet to
attach the pad. More preferably, at least the first pad
is attached by at least o.ne hooking point to a mounting
point of the base element of the brake lining thanks to
a rivet.

Advantageously, the base element of each portion
of the brake lining has at least one relief
complementary to the relief of the force and/or torque
take-up of said pad.
More preferably, the relief complementary to the
relief of the force and/or torque take-up is a half-
shear. The half-shear can be constituted by a
protuberance, for example, of rectangular shape, of
length L, width w and height h. More preferably, h is
greater than w and L/w is between 1 and 10.
Advantageously, the mounting bracket of said pad
and the front surface of the base element to which the
first pad is attached define a space between them. This
space can include an intermediate layer, more
preferably, made of damping material, where applicable
thermal insulation in order to dampen the vibrations,
in particular in the portion of the spectrum that
generates noises such as screeching, and limit where
applicable the transmission of heat between the base
and the base element of the brake lining.
More'• preferably, each base element of the lining
comprises several pads, for example five pads.
The invention, according to a preferred embodiment,
shall be well understood and its advantages shall
appear better when reading the following detailed
description, provided for the purposes of information
and in no way restrictive, and in reference to the
annexed drawings shown hereinafter:
- figure 1, shows a plan view of a base of a pad
according to the invention,
- figure 2 shows a pad according to the invention,

- figure 3 shows a brake lining base element in
two portions according to the invention intended to
receive pads according to figure 1 or 2,
- figure. 4 is a cross-section view of a half-shear,
- figure 5 is a brake lining in two portions
according to the invention with pads,
- figure 6 is a cross-section of the brake lining
of the figure 5 according to A-A,
- figure 7 is a cross-section of the brake lining
of the figure 5 according to B-B,
- figure 8 is a detailed view of the zone C of
figure 7.
The identical elements shown in figures 1 to 8 are
identified with identical numerical references.
A friction pad 1 according to the invention,
intended to be mounted on a brake lining 2 in one or
several portions, comprises a base 11 and a friction
material block 12.
According to this embodiment, the base 11 has
- a mounting bracket 111 on which can be attached
the friction material block 12, for example by-
sintering,
two hooking interfaces 112 for directly or
indirectly attaching the pad 1 to a base element (21,
22) of a brake lining 2,
and two necks 113 forming a resilient leaf
between the mounting bracket 111 and each one of the
two hooking interfaces 112.
The base can be formed using a thin sheet, for
example 2 mm thick.

The mounting bracket 111 has a quadrilateral shape
of which the large sides are slightly rounded in order
to better follow the shape of the base element (21, 22)
of a brake lining 2 to which it is intended to be
attached.
The mounting bracket 111 has at least one first
anchoring tab 1111 of the friction material block 12,
here four anchoring tabs 1111. The anchoring tabs 1111
can also be formed by stamping, even by laser cutting
of the sheet forming the base 11. Pierced zones 1112
can also be formed with apparent surfaces that are more
or less large than those shown in figure 1, but it is
however preferable to ensure that the mounting bracket
retains sufficient rigidity, left to the appreciation
of the design office. The anchoring tabs 1111 can then
be folded back in the direction of the surface of the
mounting bracket 111 whereon the friction material
block 12 shall be sintered. The anchoring tabs 1111
folded back will be able to sink into the friction
material when the latter is put into place. Moreover,
when the friction material block 12 is attached to the
surface of the mounting bracket 111, they define an
interface 13 between them.
The mounting bracket 111 can also have recesses
1113, which are here circular holes that can reinforce
the role of the anchoring tabs, or even replace them.
The hooking interfaces 112 comprise at least one
hooking point 1121. Here, these hooking points 1121 are.
constituted by circular holes. Holes make it possible
to attach the pad 1 to trie base element (21, 22) of a
brake lining 2, for example, thanks to a rivet 4. The

centres of these hooking points 1121 are arbitrarily
names here: A and A' for the hooking points 1121 of the
first hooking interface 112, and B and B' for the
hooking points 1121 of the second hooking interface 112.
In order to facilitate mounting, the two hooking points
1121 of the first hooking interface are preferably
separated by the same distance d as the two hooking
points 1121 of the second hooking interface 112. This
distance d is the length of the segment joining the
centres A, A' or B, B' of the two hooking points 1121
of the same hooking interface 112, i.e. [AA']=d and
[BB']=d.
Each hooking interface 112 further has at least
one first relief of the force and/or torque take-up
1122 because it is necessary for the forces to not be
taken up par the hooking points 1121. According to
these example embodiments, the reliefs of the force
and/or torque take-up 1122 are a housing of rectangular
shape. These reliefs of the force and/or torque take-up
1122 are able to cooperate with complementary reliefs
23 formed in the base element (21, 22) of the brake
lining 2.
The necks 113 are dimensioned so as to form a
privileged deformation zone, which enables the mounting
bracket 111 to accommodate translational and rotational
movements in every direction by limiting the forces
and/or the torques transmitted to the hooking
interfaces 112. The shape of the necks 113 can vary.
For example, according to the example embodiment of
figure 1, the latter are formed by rounded cut-outs
between the mounting bracket 111 and each of the

hooking interfaces 112, while in the example embodiment
of figure 2, the edges of the necks 113 are straight
and parallel to each other. In addition, in the example
embodiment of figure 2, the edges of the necks 113 form
and angle with the mounting bracket 111 which can be a
right angle.
The brake lining according to these example
embodiments comprises two portions, with each portion
comprising:
- a base element (21, 22) , having a front surface
(212, 222), and a dorsal surface (213, 223) on the side
of which can be attached a dovetail rail 3 for example
by rivets 7, the base element (21, 22) can be carried
out using a thin sheet, for example with a thickness of
3 mm;
- at least one first pad 1 attached to the side of
the front surface (212, 222) of the base element (21,
22) .
The base elements (21, 22) comprising the first
and the second portion of the brake lining 2 are
symmetrical. Each portion of the brake lining 2 is able
to include five pads 1.
The base elements (21, 22) comprise at least one
mounting point 24, for example a bore, to attach the
pad 1 by the hooking points 1121 of its hooking
interfaces 112, for example thanks to rivets 4.
The base elements (21, 22) also comprise at least
one relief complementary 23 to the relief of the force
and/or torque take-up 1122 of said pad, for example a
half-shear able to cooperate with the housings of the
hooking interface 112 of said first pad 1. A half-shear

is a protuberance, for example carried out by stamping
the sheet forming the base element (21, 22) of the
brake lining 2. A half-shear such as shown is of
rectangular shape, of length L, of width a and of
height h. Figure 4 shows a section of the half-shear
according to its length L. The half-shear more
preferably has a profile such that it makes it possible
to guide the positioning of the housings of the hooking
interface 112 for the setting in place of the pads 1.
The half-shears can as such have rounded or pointed
profiles, or be truncated as shown in figure 4. Such an
expanded profile for forming the complementary reliefs
23, i.e. of which the base element is wider than the
top, also makes it possible to take up any play between
the dimensions of the complementary relief 23 and those
of the corresponding relief of the force and/or torque
take-up 1122. This absence of play is necessary so that
the forces are taken up by the complementary reliefs 23,
not by the hooking points 1121 and the mounting points
24.
A brake lining 2 according to the invention can
also comprise a wedge 6, for example made of steel or
of a malleable metal, even made of fabric. More
preferably, this wedge 6 is inserted between each
hooking interface 112 of a pad 1 and the front surface
(212, 222) of the base element (21, 22) to which the
pad 1 is attached, in order to raise the entire pad.
Furthermore, the mounting, bracket 111 and the
upper surface (212, 222) of the base element (21, 22)
of the brake lining form a space 5 between them. This
space 5 can begin an empty zone or be filled with

insulation making it possible to retain the flexibility
of the mounting bracket 111.

CLAIMS
1. Friction pad (1) intended to be mounted on a
brake lining (2), comprising a base (11) and at least
one first friction material block (12), the first
friction material block (12) being attached to at least
one portion of said base (11), the base (11) and the
first friction material block (12) defining a first
plane at the interface (13) thereof, the pad (1) being
characterised in that the base (11) has:
- a mounting bracket (111) to which is attached at
least the first friction material block (12),
at least one first hooking interface (112)
distant from the mounting bracket (111) in a direction
parallel to the first plane, for directly or indirectly
attaching the pad (1) to the brake lining (2), and
- at least one first neck (113) extending parallel
to the first plane, forming a resilient leaf between
the mounting bracket (111) and the first hooking
interface (112), in order to enable the mounting
bracket (111) to accommodate translational and
rotational movements in every direction.

2. Pad (1) according to claim 1, characterised in
that at least the first hooking interface (112)
comprises at least one hooking point (1121).
3: Pad (1) according to any of claims 1 or 2,
characterised in that at least the first hooking
interface. (112) has at least one first relief of the
force and/or torque take-up (1122).
4. Pad (1) according to any of claims 1 to 3,
characterised in that at least the first relief of the
force and/or torque take-up (1122) is a housing.
5". Pad (1) as claimed in any preceding claim,
characterised in that it has two separate hooking
interfaces (112), distant from the mounting bracket
(111) in a direction parallel to the first plane, the
first hooking interface (112) and the second hooking
interface (112) being connected to the mounting bracket
(111) respectively by a first and a second neck (113).
6. Pad (1) according to claim 5, characterised in
that the first and the second hooking interfaces (112)
each include two hooking points (1121).
7. Pad (1) as. claimed in any preceding claim,
characterised in that the friction material block (12)
is sintered on the mounting bracket (111) of said base
(11).
8. Brake lining (2), in one or several portions,
each portion comprising:
- a base element (21, 22), having a front surface
(212, 222), and a dorsal surface (213, 223) on the side
of which can be attached a dovetail rail (3),
- at least one first friction pad (1) such as
defined as claimed in any preceding claim, attached to

the side of the front surface (212, 222) of the base
element (21, 22).
9. Brake lining (2) according to claim 8,
characterised in that the base element (21, 22) of each
portion of the brake lining (2) comprises at least one
mounting point (24) able to cooperate with a hooking
point (1121) of the hooking interface (112) of the pad
(1).
10. Brake lining (2) according to any of claims 8
or 9, characterised in that at least the first pad (1)
is attached par at least one hooking point (1121) to
one mounting point (24) of the base element (21, 22) of
the brake lining (2) thanks to a rivet (4).
11. Brake lining (2) according to any of claims 8
to 10, characterised in that the.base element (21, 22)
of each portion of the brake lining (2) has at least
one relief complementary (23) to the relief of the
force and/or torque take-up (1122) of said pad (1).
12. Brake lining (2) according to claim 11,
characterised in that the relief complementary (23) to
the relief of the force and/or torque take-up (1122) is
a half-shear.
13. Brake lining (2) according to any of claims 8
to 12, characterised in that the mounting bracket (111)
of said pad (1) and the front surface (212, 222) of the
base element (21, 22) of the brake lining (2) to which
the first pad (1) is attached defining a space (5)
between them.
14. Brake lining (2) according to claim 13,
characterised in that the space (5) comprises a damping
material.

15. Brake lining (2) according to any of claims 8
to 14, characterised in that each portion of the brake
lining (2) comprises several pads (1).