HK40052446B - Brake pad which collects particles and dust - Google Patents

Description

Brake pad for collecting particles and dust

The present invention relates to a pollution-free braking system intended for use in machines comprising a rotating element whose rotation is to be slowed, such as road vehicles, rail vehicles, wind turbines.

In such braking systems, the friction brakes may emit particles and dust resulting from the wear of the brake pads against the rotating member. This rotating member is for example a wheel of the vehicle or a disc driven by the wheel of the vehicle. These particles released into the surrounding environment are known to be harmful to human health. In addition, improvements to the electric motorization of motor vehicles have increased the need to deal with the particles and dust generated by the wear of the friction braking system.

It is therefore necessary to capture these particles and dust before releasing them into the surrounding environment.

Thus, the known document FR 3 057 040 describes a brake pad 10 in a disc brake, the pad comprising a base plate 1 and a lining 2 made of friction material delimited by a friction face 26, an attachment face 20, an inner edge 23, an outer edge 24, a rear edge 21, a front edge 22. The lining 2 is provided with a collection groove 3 which opens onto the friction surface 26 and is positioned near the rear edge 21, the bottom plate 1 comprising a suction aperture 17 in fluid communication with the collection groove 3. The suction hole 17 is connected to a negative pressure source through a communication means (not shown). The collecting groove 3 extends to the inner edge 23 and opens thereon in the form of a slot 33.

Such a brake pad is shown in fig. 12 and 13 and represents the prior art.

However, such gaskets have disadvantages.

In fact, the inventors have found that as the liner wears, the pumping performance decreases. Specifically, wear causes a linear increase in pressure drop that forces the turbine to reduce its flow. This results in a reduction in the performance of particle and dust capture by the collection recess and therefore in greater release of these particles and dust into the atmosphere, which is undesirable.

The present invention aims to remedy these drawbacks.

The invention relates to a brake pad comprising a base plate having an outer face and an inner face and a lining made of friction material fixed to the inner face, the lining being delimited by a friction face, an attachment face, an inner edge, an outer edge, a rear edge and a front edge, the lining being provided with at least one collection groove which is open on the friction face and is positioned at least partially in the vicinity of the rear edge, the base plate comprising at least one suction aperture which is in fluid communication with the at least one collection groove, the at least one suction aperture being connected to a source of negative pressure by means of a communication means.

The present invention aims to provide a brake pad provided with a collection groove the suction performance of which remains substantially constant as the lining of the pad wears.

This object is achieved by means of the following facts: the collecting groove extends at least one end thereof through a tube, the outer end of which opens away from the friction surface through an inlet and the inner end of which opens into the at least one collecting groove through an outlet, which forms a cross-sectional jump with the at least one groove such that, during operation, there is a negative pressure between the inlet of the tube and the at least one collecting groove, one collecting groove on each side of the tube.

With these arrangements, as shown in tests conducted by the inventors, the suction performance of the collection groove remains substantially constant, in other words, there is little change as the liner of the gasket wears.

Advantageously, the outer end is open at least near one of the edges.

For example, the outer end is open in the area of at least one of the edges, which is closest to the bottom plate and is not consumed at the end of the normal working life of the gasket.

Thus, the cross-sectional area of the tube remains constant throughout the life of the gasket.

Advantageously, the tube passes through the base plate with the outer end opening onto the outside of the base plate.

Thus simplifying the manufacture of the gasket.

Advantageously, the collecting groove consists of a single groove, which extends along said rear edge.

Advantageously, the collecting groove also extends along said front edge.

Thus, it is possible to achieve a collection of particles and dust in both directions of movement of the vehicle.

Advantageously, the collecting groove is C-shaped or E-shaped and runs along said outer edge or said inner edge.

The collection of particles and dust is therefore more efficient.

Advantageously, the at least one collecting groove consists of a plurality of individual grooves comprising a first groove running along said rear edge.

The collection of particles and dust is therefore more efficient.

For example, the plurality of grooves is two in number.

Advantageously, one of the at least one tube extends between an end of one groove and an end of another groove in the plurality of grooves.

The collection of particles and dust is therefore more efficient.

The invention will be well understood and its advantages will become more apparent from reading the following detailed description of embodiments, given by way of non-limiting example. The description makes reference to the accompanying drawings, in which:

figure 1 is a top view of a brake pad according to the invention,

figure 2 is a perspective view of a brake pad according to the invention,

figure 3 is a cross-sectional view along the collection groove of the brake pad according to the invention, taken along the line III-III of figure 2,

figure 4 is a cross-sectional view along a collecting groove according to another embodiment of the invention,

figure 5 is a perspective view of a braking system comprising a brake pad according to the invention,

FIG. 6 is a perspective view of a brake pad according to another embodiment of the invention,

figure 7 is a perspective view of a brake pad according to another embodiment of the invention,

figure 8 is a top view of a brake pad according to another embodiment of the invention,

figure 9 is a top view of a brake pad according to another embodiment of the invention,

figure 10 is a top view of a brake pad according to another embodiment of the invention,

figure 11 is a top view of a brake pad according to another embodiment of the invention,

figure 12 shows a top view of a shim according to the prior art as described above,

fig. 13 shows, as described above, a perspective view of a gasket according to the prior art.

The invention relates to a brake pad 10 of a brake in a braking device of a rotating element 9 of a machine. The invention is described below for the case where the machine is a road vehicle, in which this brake is a disc brake. However, the invention is equally applicable in the case of brake pads in brake shoes rubbing on wheels, in the case of brake pads used in vehicles (trains) on rails or in the case of brake pads used in any other industrial machine, for example in the case of wind turbines. In all cases, braking of the rotating element of the machine is achieved by friction of brake pads on this rotating element during rotation.

In a disc brake, braking occurs by friction between a disc (which is a rotating element 9) integral with the wheel of the car and two brake pads 10 pressed against this disc 9, one on each side to sandwich the disc. The disc 9 extends in a main plane and has an axis a perpendicular to this main plane as the rotational axis of the disc.

Each of the shims 10 extends in this main plane such that the thickness of the shim 10 extends along the rotation axis a.

The disc 9 rotates about an axis of rotation a in a direction of rotation FW defining a tangential direction T tangential to the circumference of the disc 9 and oriented in the direction of rotation FW and a radial direction R orthogonal to the axis of rotation a in the main plane of the disc 9.

These elements are indicated in fig. 5, which fig. 5 shows the braking device mounted on the disc 9.

In the description that follows, the terms "inner" and "outer" refer to the edges or regions of the brake pad 10 (or components thereof) that are positioned closest and farthest, respectively, from the axis of rotation a, and the terms "front" and "rear" refer to the edges or regions of the brake pad 10 (or components thereof) that are positioned upstream and downstream, respectively, with respect to the direction of circulation (which is also the direction of rotation FW) of the particles 28 emitted by the liner 2 (described below).

As illustrated in fig. 1 and 2, the brake pad 10 includes a base plate 1, also referred to as a pedestal. The base plate 1 is made of metal, for example. The base plate 1 is a flat plate with a substantially constant thickness (for example between 3mm and 5 mm), the general shape of which in its main plane is trapezoidal with straight or curved edges.

The soleplate 1 comprises a first face 13, to which the lining 2 is fixed, and a second face 14 opposite to the first face 13.

The soleplate 1 further comprises two tangs (tan) (11, 12) extending in the plane of the soleplate 1 at both lateral ends of the plate and serving to hold and guide the gasket 10.

The brake pad 10 further comprises a lining 2 made of friction material. For example, this material is a material called "phenanthroodo" (ferodo).

The lining 2 is delimited by a friction face 26 ("rubbing") face, an attachment face 20 (which is parallel to the two faces) opposite the friction face 26 and fixed to the sole plate 1, an inner edge 23, an outer edge 24, a rear edge 21 and a front edge 22. The outer edge 24, rear edge 21 and front edge 22 are convex or straight; the inner edge 23 is concave or straight.

As the lining 2 wears, the friction face 26 approaches the sole plate 1 gradually. The thickness of the lining 2 (measured along the axis of rotation a) therefore decreases as it wears.

During operation, the liner 2 (and the rotating member 9) releases the particles 28 due to friction between the liner 2 and the disc 9. The path of the particles 28 along the friction face 26 is indicated by the dashed lines in figures 1 and 2.

The lining 2 is provided with at least one collecting groove 3 which opens onto the friction face 26 and is positioned near the rear edge 21.

For example, the surface area of the portion of the friction face 26 located between the rear edge 21 and the grooves 3 is less than 10% of the total surface area of the friction face 26.

The depth of the one or more grooves 3 is equal to the height of the lining 2, in other words, the bottom of the one or more grooves 3 coincides with the first face 13 of the bottom plate 1.

The collecting groove 3 or at least one of the collecting grooves 3 extends at least partially along the rear edge 21 and is straight or conforms to the curvature of the rear edge 21. The smallest dimension of the groove 3 is its thickness measured substantially in the tangential direction T in the main plane of the gasket 10.

For example, the one or more collecting grooves 3 have a constant rectangular cross section from their upstream end to their downstream end and therefore have a constant thickness.

The liner 2 is for example provided with a single continuous groove, which is substantially straight or has one or more elbows between two or more substantially straight portions.

Alternatively, the liner 2 is provided with a plurality of collecting grooves 3, which are separated from each other. The individual grooves are understood to mean that the grooves do not communicate with each other, except perhaps through the tube 90, as described below.

Therefore, in the present invention, the liner 2 has a single collecting groove 3 (only groove), or the liner 2 has a plurality of individual collecting grooves 3.

In summary, according to the invention, the liner 2 is provided with (exhibits) at least one collecting groove 3, and this at least one collecting groove 3 consists of a single groove, at least a part of which extends along the rear edge 21, or of a plurality of separate grooves comprising a first groove 3a extending along the rear edge 21.

In the case of a single collecting groove 3, this groove comprises a single straight or curvilinear portion or several straight or curvilinear portions connected by elbows to form a network of joined groove portions. And then the collecting groove 3 is connected.

As follows, an air flow is generated in the collection groove or grooves 3, this air flow 10 being generated by a source of negative pressure (suction system).

In the part of the description below with reference to fig. 1 to 4, the case is described where there is a single collecting groove 3, which extends at least one of its ends through a tube 90 (see below), which opens near the inner edge 23. The invention is similarly applicable in the case where the collecting channel 3 opens near the outer edge 24.

"the tube 90 is open near the edge" is understood to mean that the tube 90 is open at its one end near the edge, in other words through the bottom plate 1 or directly on this edge.

In each case, one end of the tube 90 opens away from the friction surface 26. The tube 90 thus opens to the edge (21, 22, 23, 24), either through the base plate 1 or into another recess.

As illustrated in fig. 1 and 2 to 4, the collecting groove 3 is, for example, a single groove having a first end and a second end, extending along the rear edge 21.

Near the outer edge 24, the groove 3 terminates at its second end in a closed end 31, which is not open to the outer edge 24.

At this closed end 31, the bottom plate 1 comprises a suction through hole 17, which opens into the recess 3. This suction hole 17 is visible in fig. 3. The particles 28 sucked into the groove 3 thus extend into the suction apertures 17 and then into the duct 40 which is part of the suction system. The duct 40 is connected at one of its ends to the suction aperture 17. These elements are visible in fig. 3.

The duct 40 is connected to a suction mechanism (not shown) which is part of the suction system and is capable of sucking the particles 28 from the groove 3 through the duct 40.

The collecting groove 3 extends at its first end through a tube 90.

The tube 90 is composed of a continuous side wall connecting two ends and is open only at the two ends. Thus, the tube 90 forms a tunnel.

The outer end 91 of the tube 90 opens near the inner edge 23 through an inlet 911. The inner end 92 of the tube 90 opens through the outlet 922 into the collecting groove 3. The outlet 922 forms a cross-sectional jump with the groove 3, which means that the cross-sectional area increases substantially (stepwise) from the tube 90 to the groove 3.

This increase in cross-sectional area is visible in fig. 3, which is a cross-section along the line III-III of fig. 2, in other words along the collecting groove 3 and the tube 90 from the inner edge 23 to the outer edge 24.

Due to this sudden increase in cross-sectional area, during operation there is a negative pressure between the inlet 911 and the collecting groove 3 on each side of the tube 90, in other words on the tube 90.

As shown in fig. 1-3, the tube 90 passes into the inner rim 23 through its inlet 911.

Thus, during operation, air circulates from the inlet 911 to the outlet 922 through the tube 90, then in the groove 3 to the suction hole 17 and then into the duct 40, which allows to evacuate the particles and dust 28 present in the air. This air circulation is specific to the situation shown in fig. 1 to 3. In general, the terms "inlet" and "outlet" do not necessarily relate to the direction of gas flow in the tube 90.

The tube 90 has a constant circular cross-section.

Alternatively, the tube 90 has a non-circular cross-section and/or has a variable cross-section.

Advantageously, the opening of the inlet 911 is located in the region of the inner edge 23 (or in general one of the edges 21, 22, 23, 24 of the liner 2), which is closest to the soleplate 1 and which is not consumed at the end of the normal working life (service life) of the gasket 10.

Thus, the cross-sectional area of the tube 90 remains constant throughout the life of the gasket 10, and the performance of the aspirated particles 28 by the collection grooves is maintained.

This area of the lining 2 is not consumed at the end of the useful life of the gasket 10, extending above a certain percentage of the height of the lining 2 measured from the soleplate 1.

This percentage is for example equal to one third of the initial height of the lining 2 (before wear).

When the tube 90 is positioned at this percentage height equal to the initial height of the liner 2, the tube 90 acts as a visual wear indicator. In fact, when the wear of the liner 2 reaches the pipe 90, this indicates that the useful life of the gasket 10 has been reached.

According to another embodiment, the tube 90 does not open into the inner edge 23. Instead, the tube 90 passes from the collection recess 3 through the base plate 1 such that the inlet 911 opens onto the second face 14 of the base plate 1. The outlet 922 is positioned at the first face 13 of the soleplate 1. This embodiment is shown in fig. 4. Fig. 4 is the same as fig. 3, except for the location of the tube 90.

This solution offers the advantage that the tube 90 can be drilled in the floor 1 during the manufacture of the panel and that it is not necessary to form the tube 90 in the lining 2. Thus simplifying the manufacture of the panel 10 and reducing its cost.

In addition, the cross-sectional area of the tube 90 remains constant throughout the life of the gasket 10, and the ability to draw particles 28 through the collection grooves is maintained.

Whatever the embodiment, the negative pressure generated at the outlet 922 and the collection groove 3 and the fact that the cross-sectional area of the duct 90 remains constant during most of the service life of the liner 2 make it possible to maintain a constant flow rate in the collection groove 3 and, therefore, a constant suction flow rate. Thus, as the liner 2 wears, the performance of pumping the particles 28 through the collection grooves is maintained.

In the example shown in fig. 1, the outer end 91 of the tube 90 opens near the inner edge 23 through an inlet 911.

More generally, in the case of a single collecting groove 3, the outer end 91 of the tube 90 is open at least in the vicinity of one of the rear edge 21, the front edge 22, the inner edge 23 and the outer edge 24.

Another embodiment of the present invention will now be described with reference to fig. 6. Fig. 6 shows a brake pad in the railway field.

The collecting groove 3 is a single C-shaped groove running along the rear edge 21 and the front edge 22. The central portion of the collecting groove 3 extends along the outer edge 24 and connects the front and rear portions of the collecting groove 3.

The rear part of the collecting channel 3, which runs along the rear edge 21, extends at its first end through a tube 90 which is open near the inner edge 23.

The front part of the collecting channel 3, which runs along the front edge 22, extends at its second end through a further tube 90 which is open near the inner edge 23.

Each of these tubes 90 is similar to the tubes 90 described with reference to fig. 1-4.

Alternatively, each of the two tubes 90 has a different geometry, for example a different cross-section in order to balance the flow rates.

As illustrated in fig. 6, the bottom plate 1 has a suction through hole 17 which opens into the rear portion of the groove 3. The groove 3 widens here (the groove 3 may also not widen at this location).

Alternatively, the suction hole 17 opens into a front portion or into a central portion of the recess 3.

In all cases the suction holes 17 are positioned at a distance from the ends of the collecting channel 3.

Another embodiment of the present invention will now be described with reference to fig. 7. Fig. 7 shows a brake pad in the railway field.

The liner 2 has two separate grooves, a first groove 3a running along the rear edge 21 and a second groove 3b running along the front edge 22.

The first collecting groove 3a extends at its first end through a first tube 90 which is open near the inner edge 23.

The second collecting groove 3b extends at its first end through a second tube 90 which is open near the inner edge 23.

Each of these tubes 90 is similar to the tube 90 described with reference to fig. 1-4.

Alternatively, each of the two tubes 90 has a different geometry.

The first groove 3a terminates at its second end in a closed end 31 which does not open into the outer edge 24.

The second groove 3b terminates at its second end in a closed end 31 which does not open into the outer edge 24.

In the case of the first and second grooves 3a, 3b, the bottom plate 1 comprises at this closed end 31 a suction through hole 17 (not visible) which opens into each of these grooves.

Thus, each of the first and second grooves 3a, 3b is similar to the single groove 3 described in fig. 1 to 4.

In the embodiment of fig. 6 and the embodiment of fig. 7, each of the suction apertures 17 is connected to one end of a duct 40 which is part of the suction system, so that the particles 28 can be sucked by these suction apertures 17. The embodiment of fig. 6 and 7, in which the liner 2 has one or more collection recesses 3 in the vicinity of the rear edge 21 and in the vicinity of the front edge 22, makes it possible to optimize the collection of particles in both directions of movement of the vehicle (both directions of rotation of the rotating member 9 with respect to the liner 2).

Another embodiment of the present invention will now be described with reference to fig. 8.

The brake pad shown in fig. 8 is a modification of the brake pad shown in fig. 1. The two shims are identical except for the differences described below.

In the gasket in fig. 8, the collecting groove 3 extends at its first end near the inner edge 23 through a tube 90 and further at its second end near the outer edge 24 through another tube 90.

The tube 90 opens at its outer end 91 near the outer edge 24 through an inlet 911. The tube 90 opens at its inner end 92 into the collecting groove 3 through an outlet 922. The outlet 922 forms a cross-sectional transition with the groove 3.

As shown in fig. 8, the bottom plate 1 has a suction through hole 17 which opens into the collection recess 3.

As illustrated in fig. 8, the suction holes 17 are positioned at a distance from the ends of the collection recess 3, for example in the middle of the collection recess 3. The two tubes may have different cross sections depending on the position of the suction hole 17.

Thus, during operation, air circulates from the inlet 911 to the flute 3 through the two tubes 90 positioned at the first and second ends of the flute 3, then in the flute to the suction hole 17, then into the duct 40, which allows to evacuate the particles and dust 28 present in the air.

Another embodiment of the present invention will now be described with reference to fig. 9.

The brake pad shown in fig. 9 is a modification of the brake pad shown in fig. 8. The two shims are identical except for the differences described below.

The recess 3 illustrated in fig. 9 comprises a first recess 3a identical to the recess illustrated in fig. 8 and already described. The groove 3 further comprises a second groove 3b, which extends in a first portion along the front edge 22 and in a second portion along the inner edge 23, the two portions being connected by an elbow. Accordingly, an elbow is positioned at the intersection of leading edge 22 and inner edge 23.

A first portion of the second groove 3b terminates in a first end located near the outer edge 24. The first portion extends through the tube 90 at a first end. The tube 90 opens through an inlet 911 at its outer end 91 near the outer edge 24 (this reference numeral is omitted for ease of drawing).

The tube 90 opens through the outlet 922 at its inner end 92 in the first part of the second recess 3b (this reference numeral has been omitted for the sake of legibility of the drawing). The outlet 922 forms a cross-sectional transition with the second groove 3b.

A second portion of the second groove 3b terminates in a second end located near the inner edge 23. The first portion extends through the tube 90 at the second end. The tube 90 opens through an inlet 911 at its outer end 91 near the inner edge 23 (this reference numeral is omitted for the sake of legibility of the drawing).

The tube 90 opens through the outlet 922 at its inner end 92 in the second part of the second recess 3b. The outlet 922 forms a cross-sectional transition with the second groove 3b.

As referred to fig. 8, the bottom plate 1 includes a suction through hole 17, which opens into the first groove 3a. The sole plate 1 comprises a further suction through hole 17 which opens into the second groove 3b at an elbow of the second groove 3b.

In all of the above and following embodiments, when the tube 90 is opened by the inlet 911 at its outer end 91 near the outer edge 24 or inner edge 23 and near the rear edge 21 or front edge 22, alternatively, the tube 90 may be opened by the inlet 911 at its outer end 91 located at the intersection of the outer edge 24 or inner edge 23 and the rear edge 21 or front edge 22.

Alternatively, the tube 90 may pass through the base plate 1 to open at its outer end 91 through an inlet 911 which opens onto the second face 14 of the base plate 1.

Described above and illustrated in fig. 7 and 9 is the case of a plurality of individual collecting grooves 3, each extending at least one of their ends through a tube 90, which opens near one of the edges (21, 22, 23, 24) of the liner 2.

Additionally or alternatively, the liner 2 is provided with a plurality of individual collecting grooves 3, and at least one of the tubes 90 extends between an end of one of the grooves 3 and an end of another of the grooves 3.

Therefore, in the case of a plurality of collecting grooves 3, the following configuration is possible:

(a) At least one tube 90 opens at an inner end 92 in the end of the groove 3 and at an outer end 91 near one of the edges (21, 22, 23, 24) of the liner 2;

(b) At least one tube 90 opens at an inner end 92 in the end of a groove 3 and at an outer end 91 in the end of another groove 3;

(c) At least one tube 90 opens at an inner end 92 in the end of the groove 3 and at an outer end 91 near one of the edges (21, 22, 23, 24) of the liner 2, and at least another tube 90 opens at an inner end 92 in the end of the groove 3 and at an outer end 91 in the end of another groove 3.

In the case of a single collecting groove 3, there is a configuration (a) with a single tube 90 opening in one end of the groove 3, or with two tubes 90 each opening in one of the two ends of the groove 3.

Fig. 7 and 9 each show an example of the configuration (a) in the case of two grooves 3.

Fig. 10 described below shows an example of the configuration (b) in the case where the liner 2 is provided with only two separate collecting grooves 3 (i.e., the first groove 3a and the second groove 3 b). The first and second grooves 3a, 3b are extensions of each other and extend along the rear edge 21. A single tube 90 extends between a first end of the first groove 3a and a first end of the second groove 3b.

Thus, the tube 90 opens through the inlet 911 at its outer end 91 in the collecting groove 3b. The inlet 911 forms a cross-sectional jump with the groove 3b. The tube 90 opens through the outlet 922 at its inner end 92 in the collection recess 3a. The outlet 922 forms a cross-sectional transition with the groove 3a.

The second end of the first recess 3a is a closed end 31 which is not open at the outer edge 24.

At this closed end 31, the bottom plate 1 has a suction through hole 17 which opens into the recess 3.

The second end of the second groove 3b is open at the inner edge 23.

Fig. 11 described below shows an example of the configuration (c) in the case where the liner 2 is provided with only two separate collecting grooves 3 (i.e., the first groove 3a and the second groove 3 b).

The first groove 3a is L-shaped and has a short portion 3a-C running along the front edge 22 and a long portion 3a-L running along the outer edge 24.

The short portions 3a-C extend from the corners of the front edge 22 and the outer edge 24 to near the inner edge 23, where they terminate in ends. The short portions 3a-C extend through the tube 90 at this end. The tube 90 opens through an inlet 911 at its outer end 91 near the inner edge 23 and through an outlet 922 at its inner end 92 in the first groove 3a.

The long portions 3a-L extend from the short portions 3a-C, the long portions being connected to the short portions by elbows. This elbow is therefore positioned at the intersection of leading edge 22 and inner edge 24.

The base plate 1 has a suction through-hole 17 which opens into the first recess 3a at an elbow of the first recess 3a.

The long sections 3a-L extend to the corners of the rear edge 21 and the outer edge 24, where they are bent towards the rear edge 21 up to the ends. This end is positioned to face the end of the second groove 3b.

The second groove 3b extends along the rear edge 21 from this end facing the end of the long portion 3a-L of the first groove 3a to the other end opening on the inner edge 23.

The tube 90 extends between the ends of the first grooves 3a and the ends of the second grooves 3b facing each other.

Thus, the tube 90 opens at its outer end 91 in the second groove 3b through the inlet 911. The inlet 911 forms a cross-sectional jump with the second groove 3b. The tube 90 opens through the outlet 922 at its inner end 92 in the collection recess 3a. The outlet 922 forms a cross-sectional transition with the groove 3a.

Other configurations of the grooves 3 are possible, such as a single groove 3 extending along almost the entire circumference of the liner 2, or a plurality of grooves 3 that do not intersect and are in communication with each other through at least one tube 90 and that together extend along almost the entire circumference of the liner 2.

Claims (7)

1. Brake pad (10) comprising a sole plate (1) having an outer face (14) and an inner face (13) and a lining (2) made of friction material fixed to the inner face (13), the lining being delimited by a friction face (26), an attachment face (20), an inner edge (23), an outer edge (24), a rear edge (21) and a front edge (22), the lining being provided with at least one collection groove (3) which opens onto the friction face (26) and which is positioned at least partially in the vicinity of the rear edge (21), the sole plate comprising at least one suction aperture (17) which is in fluid communication with the at least one collection groove (3), the at least one suction opening (17) is connected to a source of underpressure by means of a communication means, the at least one collection groove (3) being characterized in that it extends at least one end thereof by at least one tube (90), the outer end (91) of which opens away from the friction surface (26) by an inlet (911), and the inner end (92) of which opens into the at least one collection groove (3) by an outlet (922) which forms a cross-sectional jump with the at least one groove (3) such that, during operation, at the inlet (911) of the at least one tube with the at least one collection groove (3) In the region of at least one of the rear edge (21), front edge (22), inner edge (23) and outer edge (24), which is closest to the floor (1) and is not consumed at the end of the normal working life of the brake pad (10), said region extending above a certain percentage of the height of the lining (2) measured from the floor (1).

2. Brake pad (10) according to claim 1, characterized in that the at least one collecting groove (3) consists of a single groove, which extends along the rear edge (21).

3. Brake pad (10) according to claim 2, characterized in that the at least one collecting groove (3) also extends along the front edge (22).

4. Brake pad (10) according to claim 3, characterized in that the collecting groove (3) is C-shaped or E-shaped and runs along the outer edge (24) or the inner edge (23).

5. Brake pad (10) according to claim 1, characterized in that the at least one collecting groove (3) consists of a plurality of individual grooves comprising a first groove (3 a) running along the rear edge (21).

6. The brake pad (10) of claim 5, wherein the plurality of individual grooves is two in number.

7. The brake pad (10) of any one of claims 5 to 6, wherein one of the at least one tube (90) extends between one end of one groove and one end of another groove in the plurality of grooves.