Brake pad

Abstract

TITLE: Brake pad Brake pad comprising a base (3) and a lining (2) supported on the base (3), the lining (2) comprising a friction surface (21) capable of coming into contact with a rotor (11) and a braking particle collection groove (4) open on the friction surface (21), said collection groove (4) being in fluid communication with: a conduit (41) opening out of the friction surface at a mouth (42), the conduit (41) having a first diameter (D1) over a major part (41.1) of its extent; and a suction hole (5) capable of being connected to a vacuum source, said pad (1) comprising a blocking device (6) configured to prevent a body (8) of a dimension greater than a limit value (Dm) from entering the conduit (41) via the mouth (42), the limit value (Dm) being less than or equal to 90% of the first diameter (D1). Figure 4

Description

Title of the invention: Brake pad Technical field

[0001] The field of the present disclosure is that of non-polluting braking systems, intended to be used in machines comprising a rotating element whose rotation is to be braked, such as for example road or rail vehicles, or such as structures comprising rotating elements, for example wind turbines. In such braking systems, particles and dust are emitted by friction braking as a result of the abrasion of brake pads against the rotating element. This rotating element is for example the wheel of the vehicle, or a disc driven by the rotating element. It is known that these particles dispersed in the ambient environment are harmful to the health of individuals, as well as to the environment.

[0002] In addition, the progression of electric motors for motor vehicles has reinforced the need to treat particles and dust resulting from the abrasion of friction braking systems. There is therefore a need to capture these particles and dust before they are released into the ambient environment.

[0003] More specifically, the present disclosure relates to a brake pad, as well as a braking system comprising such a pad. Prior art

[0004] In braking systems, a known example 10 of which is illustrated in [Fig.l], it is customary to use brake pads 1 to brake the rotation of a rotating element 11 by contact. This friction action, as explained above, produces a significant quantity of particles.

[0005] Patent document FR3087238 illustrated in [Fig.2], describes a plate 1 with a particle suction slot 4 which opens radially into a mouth 42 ([Fig.2] at the top) on one side of the lining, in order to collect these particles more efficiently than a groove opening only onto the fiction surface 21. Another solution ([Fig.2] at the bottom) consists of arranging a mouth 42 in the form of an orifice. This solution has the advantage of maintaining the level of depression and flow rate throughout the wear of the plate. Indeed, when the mouth 42 is a slot, its air inlet surface decreases with the wear of the lining 2. The dimensions of the orifice which forms the air inlet mouth are adapted to obtain sufficient levels of depression and flow rate.

[0006] In operation, and more particularly in the case of a mouth in the form of an orifice, the mouth 42 can be partially or totally obstructed by bodies foreign matter, such as small pebbles or mud, which can render the system inoperable or reduce its efficiency: the suction power must be increased to continue capturing the same quantity of particles.

[0007] The present disclosure therefore aims to at least partially overcome the drawbacks of the state of the art cited above.

[0008] In particular, an objective of the present disclosure is to provide a wafer which guarantees the maintenance of suction efficiency throughout its lifetime. Abstract

[0009] The above-mentioned objectives are achieved in particular by a brake pad comprising a sole and a lining supported on the sole, the lining comprising a friction surface capable of coming into contact with a rotor and a braking particle collection groove open on the friction surface, said collection groove being in fluid communication with: a conduit opening out of the friction surface at a mouth, the conduit having a first diameter over a major part of its extent; and a suction hole capable of being connected to a vacuum source, said pad comprising a blocking device configured to prevent a body of a dimension greater than a limit value from entering the conduit via the mouth, the limit value being less than or equal to 90% of the first diameter.

[0010] Thus, in a particularly effective manner, the solution according to the present disclosure makes it possible to provide additional protection to the simple geometry of the mouthpiece. Indeed, it has been found by the inventors that, although bodies of dimensions substantially equal to that of the mouthpiece are blocked by the latter, it is mainly bodies of dimensions slightly smaller than that of the mouthpiece which can be the most problematic. Indeed, a body substantially smaller than the dimension of the mouthpiece will not pose a problem of obstruction: it will be sucked in and conducted through the groove with the collected particles towards an outlet of the system or towards a treatment device downstream of the braking system such as a filter, and will not interfere with the operation of the system.However, experiments show that a body just smaller than the first diameter, with a dimension greater than 90% of the duct dimension, will have a high probability of getting stuck at the mouth, or in the duct, by an arching or similar phenomenon, and of blocking the air flow entirely or partially, thus reducing the efficiency of the collection action: in case of blockage of the suction mouth, the suction power will have to be increased to maintain a target depression and a suitable collection rate. Moreover, such an intrusion of a body into the system can also damage its components (piping, filter, etc.). The proposed solution therefore makes it possible to increase the reliability of the . particle collection system.

[0011] The bodies in question may be of any shape, although they are shown in spherical shape in the drawings by way of example and for the sake of clarity. The term "size", "dimension" or "diameter" then means the largest dimension of the body, regardless of its shape.

[0012] The plate according to the present disclosure can be used for example in a road vehicle (cars, buses, heavy goods vehicles, etc.) or rail vehicle (trains, trams, metros, etc.), but also in a stationary rotor machine, such as a wind turbine or an industrial machine.

[0013] In examples, such a solution may be implemented on a braking system comprising two pads positioned opposite each other, on either side of a rotor, so as to each come into contact with the latter (brake disc). The pads may each comprise a friction surface, in which at least one collection groove may be arranged, the friction surface being configured to come into contact with the rotor.

[0014] The pads may be positioned so that the friction surfaces of the linings comprise at least one flat portion substantially perpendicular to the axis of rotation of the rotor, on which contact can be made.

[0015] In other examples, the pads and their linings may be arranged differently, so as to be used in a drum brake system: the friction surface of the pads is then cylindrical and comes into radial support on an internal face of the drum.

[0016] The linings are formed by a friction material, which may comprise a material commonly referred to as “ferodo”. The friction material may be chosen from a group comprising: organic, metallic, semi-metallic, or even ceramic materials.

[0017] Although such pads are typically used in pairs, the remainder of the description will focus on one pad. It is possible to use two identical pads according to the present disclosure, or at least one pad according to the present disclosure in a braking system having two or more pads.

[0018] The conduit may have a cross-section having a first diameter over a majority of its extent, i.e. more than 50% of its length has a constant diameter, preferably more than 80% of its length. The reader will understand that if the cross-section of the conduit is not circular, the conduit may have a “first dimension” which will also be critical for the passage (or not) of mud or stones. For example, if the cross-section is rectangular, the “first dimension” is the distance between the two largest sides of the rectangle. If it is a conduit with an elliptical cross-section, the first dimension will be the length of the minor axis of the cross-section el liptic of the duct. According to other examples, the duct 41 may be polygonal or oblong in shape. Generally, depending on the shape of the section of the duct 41, the “first diameter” may correspond to the inscribed circle, the equivalent section or the equivalent aeraulic diameter of the duct 41.

[0019] Thus, the present disclosure will use the expression “first diameter” by misuse of language even when the conduit is not of circular section.

[0020] The features set out in the following paragraphs may, optionally, be implemented, independently of one another or in combination with one another:

[0021] In examples, the limit value is less than or equal to 70% of the first diameter. Thus, (at least) all bodies with dimensions greater than 70% of the diameter of the major part of the conduit are blocked.

[0022] In examples, the limit value is less than or equal to 32%, preferably less than or equal to 16% of the first diameter.

[0023] In examples, the first diameter is between 1 mm and 6 mm, the first diameter preferably being approximately 4 mm.

[0024] In examples, the locking device is attached to the lining or is an integral part of the lining or the sole.

[0025] In examples, the blocking device comprises an obstruction element arranged opposite the mouth and at a distance therefrom equal to the limit value.

[0026] In examples, the obstruction element is integral with the sole, preferably the obstruction element is a U-shaped extension of the sole. Such a shape of obstruction element makes it possible, among other things, to limit the accumulation of mud at the mouth, which can, once dry, prevent or hinder suction.

[0027] In examples, the blocking device comprises a grid arranged around said mouth.

[0028] In examples, said grid may have a dome shape. This shape may have the advantage of very little hindrance to air suction and thus of obtaining a satisfactory air flow in the groove. Alternatively, the grid may also be of a flat shape, or of any other shape making it possible to cover the mouth.

[0029] In examples, the grid is integral with an insert crossed by a channel and attached to the duct. The channel having the function of ensuring the fluidic connection between the duct, or directly the groove, and the exterior of the lining. This insert solution can make it possible to adapt the locking means according to the present disclosure to an existing wafer, not having a locking means in its original manufacture.

[0030] In examples, said mouth opens through an outer surface of the plate, the grid being attached to said outer surface covering said mouth, preferably the grid is welded to said outer surface.

[0031] Said outer surface may be a surface of the sole or the lining, or it may extend over both the lining and the sole of the insert. Said outer surface may be a surface of the sole disposed opposite the fastening surface receiving the lining. The conduit may then pass through the lining and the sole. In examples, said outer surface may be a surface on one side, for example lateral or radial (internal or external), of the lining and / or the sole.

[0032] In examples, the mouthpiece has a second diameter that is in particular at least 10% smaller than the first diameter of the conduit, the mouthpiece forming all or part of the blocking device. In accordance with the definition of the first diameter mentioned above, the second diameter may, by misuse of language, designate a critical dimension of a non-circular section of the mouthpiece.

[0033] In examples, the conduit comprises, in addition to the major part defining the first diameter, a portion of reduced section, preferably conical, extending from the major part to the mouth. Such a conduit with a first and a second diameter can be obtained by drilling using a conical drill, the stroke of the drill stopping before its head fully emerges from the material. In examples, such a second diameter can be arranged on an insert, which can be pierced with a channel and inserted into the conduit. This solution can allow the application of the locking means solution to an existing plate.

[0034] According to another aspect, the present disclosure relates to a nozzle for capturing braking particles comprising: a collection groove configured to be positioned opposite a brake rotor; a conduit, fluidically connected to the collection groove and comprising a mouth, the conduit having a first diameter over a major part of its extent; and a suction hole configured to be connected to a vacuum source, said nozzle comprising a blocking device configured to prevent a body of a dimension greater than a limit value from entering the conduit via the mouth, the limit value being less than or equal to 90% of the first diameter.

[0035] According to examples, the limit value is less than or equal to 70% of the first diameter.

[0036] According to examples, the limit value is less than or equal to 32%, preferably less than or equal to 16% of the first diameter.

[0037] According to examples, the first diameter is between 1 mm and 6 mm, the first diameter preferably being approximately 4 mm.

[0038] According to examples, the blocking device comprises an obstruction element arranged opposite the mouth and at a distance therefrom equal to the value limit.

[0039] According to examples, the blocking device comprises a grid arranged around said mouth.

[0040] According to examples, the grid is secured to an insert crossed by a channel and attached to the conduit.

[0041] According to examples, the mouthpiece has a second diameter, in particular at least 10% smaller than the first diameter of the conduit, the mouthpiece forming all or part of the blocking device.

[0042] According to examples, the conduit comprises, in addition to the major part defining the first diameter, a portion of reduced section, preferably conical, extending from the major part to the mouth.

[0043] According to another aspect, the present disclosure relates to a braking system comprising a rotor and: a pair of pads as described above; and / or one or more particle capture nozzles as described above, the braking system further comprising a source of vacuum fluidly connected to the suction hole of a groove of each pad and / or each capture nozzle.

[0044] The invention also provides other technical advantages. The proposed solution is particularly easy to implement, possibly on existing pads or existing braking systems, it is economical and of a shape and volume adapted to the highly constrained environment of a braking system. Also, limiting the introduction of large foreign objects into the pneumatic circuit makes it possible to protect against potential impacts on the filter present in the pneumatic circuit, as a result of which there are fewer mechanical constraints on the filter: a less solid filter or a more flexible or less expensive material can be chosen. Brief description of the drawings

[0045] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which:

[0046] [Fig-1] shows a schematic representation of a disc brake.

[0047] [Fig.2] shows a schematic representation of two examples of brake pads known from the state of the art, each comprising a collection groove and a conduit whose mouth is slot-shaped or orifice-shaped.

[0048] [Fig.3] shows a sectional view of an example of a brake pad showing the groove as well as the duct, the suction hole and the opening of said groove on the friction surface.

[0049] [Fig.4] shows an example of a blocking device comprising a U-shaped obstruction element.

[0050] [Fig.5] shows an example of a locking device comprising an element L-shaped obstruction.

[0051] [Fig.6] shows an example of a locking device comprising an integral grid of an insert.

[0052] [Fig.7] shows an example of a blocking device comprising an attached grid.

[0053] [Fig.8] shows an example of a locking device comprising a portion of reduced section at one end of the conduit.

[0054] [Fig.9] shows an example of a variant in which the groove is provided on a nozzle, distinct from the friction surface, comprising a mouthpiece on which it is possible to apply a blocking device according to the present disclosure.

[0055] [Fig. 10] shows another example of the variant of [Fig.9], in which the groove has several mouths.

[0056] [Fig. 11] shows a sectional view of an example similar to [Fig. 10], including a locking device at each of the mouthpieces. Description of the embodiments

[0057] The drawings and the description below contain, for the most part, elements of a certain character. They may therefore not only serve to better understand the present disclosure, but also contribute to its definition, if necessary.

[0058] In the various figures, the same references designate identical or similar elements. For the sake of brevity, only the elements which are useful for understanding the embodiment described are shown in the figures and are described in detail below.

[0059] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "rear", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "upper", "lower", etc., or to orientation qualifiers, such as "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the usual designations of a braking system in its normal position of use. The terms "axial", "radial" are in particular considered, unless otherwise stated, relative to the axis of rotation of the braked rotor. Furthermore, the term "substantially" is to be interpreted as indicating that the result obtained is as precise as the known method for measuring it.

[0060] Figures 1 to 3 illustrate an example of a state-of-the-art braking system. This is an example on which it is possible to apply the proposed solution by replacing at least one of the brake pads with that of one of Figures 4 to 8. Unless otherwise stated, the characteristics of the pads of Figures 1 to 3 which remain unchanged can be applied to the pad according to the present di- popularization.

[0061] More specifically, [Fig.l] shows an example of a braking system 10 known from the state of the art, comprising a rotor 11, in this example a brake disc, surmounted by a caliper 12 provided with two brake pads 1 partially visible here, positioned on either side of the annular faces of the disc. The rotor 11 rotates around an axis of rotation A.

[0062] This example of braking system 10 constitutes an example of a case of application of the proposed solution, but is not limiting. Indeed, it is possible to apply the solution to any braking system using the friction action of brake pads, such as for example a drum brake. In addition, this type of braking system illustrated by way of example being common in the automotive field, it is also possible to equip braking systems in other fields, for example other types of road or rail vehicles, or in particular in the field of industrial rotating machines, or even stationary structures such as wind turbines.

[0063] [Fig. 2] shows two examples of brake pads 1 provided with a lining 2 fixed on a base 3. The pads 1 each comprise a lining 2, capable of coming into contact with a rotor 11. The linings 2 comprise in particular a friction surface 21, at least partially included in a plane perpendicular to the axis of rotation A of the rotor 11 when they are mounted on a braking system of the type as illustrated in [Fig. 1].

[0064] The lining 2 may be fixed to a sole 3, these together forming a braking pad 1. The sole 3 may be of a general plate shape, for example metallic. According to examples, the sole 3 may be of larger dimension than the lining 2, so as to protrude on sides (23, 24, 25, 25) of the lining 2.

[0065] Optionally, the sole 3 can serve as an interface between the pad 1 and other elements of the braking system 10, for example sensors, or fixing elements of a caliper 12 or a translational drive mechanism. If the lining 2 has the function of coming into contact with the rotor to be braked, the sole 3 does not come into contact with the rotor during the braking action. The lining 2 can typically be fixed to the sole 3 by a fixing surface, arranged opposite the friction surface 21.

[0066] During braking, the friction surfaces 21 of the pads 1 are pressed against the rotor 11. This contact causes friction forces, applied in a direction substantially tangent to the rotation of the rotor 11, represented schematically by arrows in [Fig.2], which cause the progressive wear of the linings. As explained previously, particles originating from the friction material of the linings are thus generated, these particles generally being polluting and toxic. These particles are at least partly collected by collection grooves 4 arranged in the lining(s) 2.

[0067] The groove 4 typically comprises a conduit 41 which ends in a mouth 42 particularly visible in this [Fig.2]. The groove 4 also comprises a suction hole 5 (visible in [Fig.3]). The function of the conduit 41 is to allow air to enter through its mouth 42, sucked in by the suction hole 5.

[0068] The groove 4 also opens onto the friction surface 21 through an opening 45 separate from the mouth 42 and the suction hole 5. This opening 45 is configured to be blocked by the annular surface of the rotor 11 which comes into contact with the friction surface 21, in particular during the braking action. An air flow is then created by the vacuum source which sucks air through the suction hole 5 which has no other choice but to enter the groove 4 through the conduit 41, the opening 45 remaining blocked by the rotor. A vacuum is then formed at the level of the portion of the rotor opposite said opening 45. It is in particular through this opening 45 that the braking particles enter the groove 4 and are collected. Said opening 45 may be provided over at least part of the length of the groove, which may ultimately form a trench in the lining 2.The groove may be arranged such that when contact is made with the rotor on the friction surface 21, the annular surface of the rotor blocks said opening of the groove 4.

[0069] The two examples of [Fig. 2] differ from each other with regard to the geometry of the conduit 41 and its mouth 42, one (in the upper part of the figure) being produced in the form of an open slot on the friction surface 21, which has the disadvantage of shrinking with wear of the lining, and the other example (at the bottom of the figure) proposes an improvement of the first example with a mouth 42 in the form of a non-open orifice on the friction face 21 thus forming a conduit arranged in the lining 2.

[0070] An example of groove 4, opening 45, mouth 42, conduit 41 and suction hole 5 is particularly visible in [Fig. 3]. In this example, the mouth 42 is provided at a lateral side of the lining 2, the suction hole 5 being provided passing through the surface for fixing the lining 2 on the sole 3, and opening on the side of the sole 3 opposite the lining 2. The mouth 42 and the suction hole 5 are fluidically connected by the groove 4, and are in this example each arranged at one end of the groove 4.

[0071] [Fig.4] schematically represents an example of the present disclosure.

[0072] The conduit 41 and, here, the mouth 42 have the same diameter called “first diameter DI”. In this example, the conduit and the mouth are circular, but it It is possible to envisage that their sections are of any shape, for example polygonal, elliptical or oblong, and / or different from each other. The duct 41 shown here has a section of constant dimension over the entire extent of the duct 41. It is possible, according to other examples, to envisage a duct 41 whose section has variations in size or shape. The duct 41 extends here in a rectilinear manner, but it is possible to envisage other examples with a duct having curved parts or changes in direction. It is nevertheless advantageous for the duct to have, at least over a major part 41.1 of its extent, a constant section and to extend in a predominantly rectilinear manner. This makes it possible to avoid pressure losses and disturbances to the air flow.

[0073] The conduit 41 may open through a surface of the sole 3, or through a side of the lining 2 distinct from the friction surface 21, or even at the joint between the sole 3 and the lining 2. A side of the lining distinct from the friction surface 21 may for example be a lateral side 25, 26, or a radially inner side 23, or radially outer side 24 of the lining 2.

[0074] In this example, the conduit 41 passes through the lining 2 in which the groove 4 is formed, then the sole 3 on which the lining is fixed. The lining 2 is fixed to the sole on a fixing surface, and the mouth 42 of the conduit 41 is provided on an outer surface 43 of the sole 3, the outer surface 43 here being on a side of the sole opposite the fixing surface.

[0075] In examples, the lining 2 may comprise several mouths 41 and possibly several suction holes 5. In examples, a groove 4 may comprise one or more mouths 41 and / or one or more suction holes 5. In examples, the conduit 41 and the suction hole 5 may each be provided in positions distinct from the ends of the groove 4. In addition, the lining 2 may comprise one or more collection grooves 4. Furthermore, a plate 1 may also comprise one or more linings 2. Typically, the groove 4 extends from the conduit 41 to the suction hole 5, each positioned at one end of the groove 4.But it is possible to envisage that the suction hole 5 is located for example in the center of the groove 4, and that two conduits 41 are arranged at two ends of the groove 4, or any other configuration finally making it possible to obtain a flow of air through the groove 4, from at least one conduit 41 to at least one suction hole 5.

[0076] In examples, the groove 4 extends in a rectilinear manner in a single direction, which is substantially perpendicular to the direction of the friction forces (as represented [Fig.2] by arrows). Indeed, this configuration makes it possible to cover as much of the surfaces participating in the friction as possible and thus effectively collect the particles emitted during the friction. According to other examples, the groove 4 may also have non-rectilinear portions, and / or portions not oriented perpendicular to the friction forces. For example, the groove may form angles, curves, changes of direction and possibly have more than two ends, in particular several branches extending in different directions. For example, the groove may have several rectilinear portions connected by angles.

[0077] In cases having several grooves 4, it is possible for each of the grooves to have its own opening 45 on the friction surface 21, each performing a particle collection action. Said opening 45 allows the braking particles to enter the groove 4 and be collected by the air flow. The particles are then brought by the action of the vacuum source downstream of the braking system 10, for example into a treatment unit such as a filter.

[0078] The suction hole 5 may open onto the base 3 of the plate 1. For example, the suction hole 5 may form a channel opening from the fixing surface of the lining 2 and passing through the base 3. The suction hole may be fluidically connected, directly or indirectly, to a source of depression.

[0079] The vacuum source may be a suction device, for example, comprising a fan or a turbine. The suction hole 5 may be connected to the vacuum source directly, for example by a sealed fluid connection 51, of the type of a pipe or a hose. The suction hole 5 of the groove 4 may be connected to the vacuum source indirectly, for example by an element other than a simple fluid connection, for example interposed between the suction hole 5 of the groove 4 and the vacuum source, such as a filter. Or, the suction hole 5 of a first groove 4 may be fluidically connected to a conduit 41 of a second groove 4, of the same pad or of another brake pad.

[0080] The plate 1 according to the present disclosure comprises a blocking device 6, examples of which are shown in FIGS. 4 to 8. The blocking device 6 is configured to prevent a body 8 with a dimension greater than a limit value Dm from penetrating, even partially, into the conduit 41 via the mouth 42, the limit value Dm being less than or equal to 90% of the first diameter. Thus, the body 8, even if it has a dimension smaller than the first diameter of the conduit, cannot penetrate into the conduit 41 via the mouth 42 if it is of a dimension greater than the value Dm. It is thus possible to protect the particle collection system and maintain its efficiency at a satisfactory level without having to modify the geometry of the conduit 41, which is generally sized to allow a sufficient level of depression in the groove 4.Indeed, making a smaller duct, for example a circular duct with a diameter of Dm, would reduce the suction efficiency and would harm the particle collection operation.

[0081] The limit value Dm is less than the first diameter DI of the conduit 41. In examples, the value Dm is less than or equal to 70% of the first diameter of the conduit 41. In other examples, the value Dm is less than or equal to 32% of the first diameter, or even less than or equal to 16% of the first diameter of the conduit 41. The minimum internal dimension of the conduit may be between 1 mm and 6 mm, preferably approximately 4 mm.

[0082] According to the example shown in [Fig.4], the blocking device 6 comprises an obstruction element 61 arranged opposite the mouth 42 and at a distance from the latter equal to the limit value Dm. The obstruction element 61 has in particular an obstruction surface 46 arranged to face the outer surface 43. The obstruction surface 46 being distant from the outer surface 43 by a value Dm, any body of dimension greater than or equal to Dm will be blocked before reaching the mouth 42. The obstruction surface 46 may be substantially parallel to the outer surface 43. The obstruction element 61 is arranged to extend over the entirety of the air inlet surface defined by the mouth 42. Thus, if the obstruction element 61 extends from one side of the mouth 42, the latter extends until it at least reaches, or even exceeds, the opposite side of the mouth 42.The obstruction element 61 extends over a length at least equal to the first diameter of the conduit 4L. The obstruction element 61 extends with a width L at least equal to the first diameter of the conduit 4L. In a variant not illustrated in [Fig. 4], the obstruction element 61 only partially covers the mouth 42, a partial covering being sufficient to prevent the introduction of an unwanted object 8 into the conduit 4L.

[0083] The obstruction element 61 may be integral with the sole 3, as shown in Figures 4 and 5. In the example of [Fig. 4], the obstruction element 61 is a U-shaped extension of the sole 3. This shape is for example obtained by folding a protrusion formed integrally with the sole. In the example in [Fig. 5], the obstruction element 61 is made in an L-shape. Generally speaking, regardless of the shape of the obstruction element 61, the obstruction element 61 comprises a portion directly opposite the mouth 42.

[0084] The obstruction element 61 has the advantage of allowing air to pass over a gap which extends over a relatively long length compared to its width which is equal to the value Dm. In fact, a gap in the form of a “band” of width Dm is formed between the outer 43 and obstruction 46 surfaces, over a major part of the periphery of the mouth 42. This allows the suction to be maintained despite the presence of a body 8 wedged between the obstruction surface 46 and the outer surface 43, the latter blocking only a minor part of the total surface of the gap.

[0085] In [Fig.5], the conduit 41 passes through the lining 2 and opens onto a surface of the lining which may be an internal or external radial surface, or an upstream or downstream lateral surface.

[0086] In [Fig. 6], another example of a blocking device is shown, in which it comprises a grid 62 arranged around the mouth 42. The grid 62 is provided with openwork zones 64, preferably distributed regularly over the surface of the grid 62. The grid 62 may in particular have a dome shape, or a half-sphere shape as shown in the example. This makes it possible to maximize the air flow. Other shapes are conceivable. The openwork zones 64 may all have the same shape and the same size, or have different sizes and shapes, as is the case in the examples shown in Figures 6 and 7.

[0087] The openwork zones 64, whatever their shape and the shape of the grid, have a minimum dimension equal to the value Dm. In this way, any body of size greater than the value Dm is blocked by the grid 62, prevented from reaching the mouth 62 due to the size of the openwork zones 64.

[0088] In the example shown in [Fig.6], the grid 62 is secured to an insert 63, here introduced into a bore 66 made to widen the conduit 4L. Said insert 63 is crossed by a channel 65, this channel being able to have a cross section identical to that of the first diameter of the conduit 41, so as not to modify the suction performance of the conduit 4L. In other words, the channel 65 extends in the continuity of the conduit 4L. Said channel 65 can have a constant cross section over at least a major part of its extent. The channel 65 can be obtained by drilling in the insert 63, or any other means known to those skilled in the art. In this example, the mouth 42 does not open onto an external surface 43 of the plate, but opens onto the bottom of the bore 66, thus forming a shoulder.The insert 63 is introduced in abutment up to said shoulder at the bottom of the bore 66, at the mouth 42 of the conduit 41, which is then fluidly connected to the channel 65. The assembly between the insert 63 and the bore 66 can typically be achieved by shrink fitting, or any other means known to those skilled in the art. In examples, the insert is an insert useful for molding during sintering of the lining 2 on the sole 3.

[0089] The grid 62 can be attached to said insert 63 at the end opposite that which is in abutment at the bottom of the bore 66. The grid 62 can then be welded to the insert 63, or fixed by any other means known to those skilled in the art. Said grid 62 can also be made integrally with said insert, the openwork zones 64 being able for example to be obtained by suitable machining operations in the material of the insert 63.

[0090] In other examples, when the blocking device 6 does not include an insert 63, the grid 62 can be attached directly to the external surface 43 through which the conduit 4L opens. The grid is then attached to cover said mouth 42, on the external surface 43 (or on any other surface of the lining if the conduit opens there). For example, as shown in [Fig.7], the grid is attached directly to the outer surface 43 of the sole. In examples, the grid 62 is welded to said outer surface 43, or fixed by any means known to those skilled in the art. The grid 62 may also be integral with the sole 3, or another part of the plate 1.

[0091] In other examples, the blocking device 6 may comprise, as a variant or in addition to a grid 62, a plate or even a plug pierced with one or more through orifice(s) acting as openwork zones 64.

[0092] In the example shown in [Fig.8], the mouth 42 has a second diameter smaller than the first diameter of the conduit 41, it is then here the mouth 42 itself, by its geometry, which forms the blocking device 6. For example, the second diameter can be smaller than the first diameter by at least 10%. In this case, the body 8 larger than the value Dm will be blocked by said reduced mouth 42, and will not reach the conduit 41. This example can be combined with another example of blocking means, for example which can also comprise a grid 62 around the reduced mouth 42, and / or an obstruction element 61 opposite the reduced mouth.

[0093] The conduit 41 comprises, in addition to the major part 41.1 of first diameter, a portion of reduced section 44 extending from the major part 41.1 to the mouth 42, which then has a second diameter smaller than the first diameter. Said reduced portion 44 may be of conical shape, the diameter of the reduced portion then decreasing linearly from the major part 41.1 of the conduit 41 to the mouth 42. It is also possible to provide a reduced portion 44 whose diameter decreases so as to form a curve, for example an arc of a circle. Depending on its shape, the reduced portion 44 may be obtained, for example, by drilling using a conical drill or by machining using a hemispherical milling cutter. The reduced portion 44 can be configured so that its diameter decreases, from the major part 41.1 of the conduit 41 to the mouth 42, without having any portion of constant diameter.Indeed, the presence of a bearing of constant diameter could constitute an area in which a body, of a size slightly smaller than the size Dm of the mouth 42, could remain stuck, and obstruct the reduced portion 44.

[0094] According to a variant, it is possible for the collection groove 4, which is fluidically connected to the source of depression, to be arranged at a distance from the friction linings 2. Indeed, the groove can also be separate from the linings, or even separate from the pads. In other examples, the groove can be integral with the pad but separate from the friction surface 21.

[0095] According to an example illustrated in [Fig.9] and 10 which can be an alternative or a complement to the plate described so far, the groove 4 can be provided on a capture nozzle 100, positioned at a distance from the friction surface 21. The example illustrated has only one groove, but it is possible to envisage several grooves on a single nozzle. In the same way, it is possible to provide several capture nozzles for the same rotor, in particular two nozzles facing each other, on one side and the other of the brake rotor. The nozzle(s) can be fixed to the yoke or the caliper.

[0096] The collection groove 4 of the nozzle 100 comprises an opening 45 configured to be positioned opposite the annular surface of the rotor 10. The annular surface may typically be the one that comes into contact with the friction lining of the pads during the braking action. Thus, the opening 45 of the groove 4 of the nozzle 100 can carry out the operation of capturing the braking particles.

[0097] In a similar manner to the examples described above in which the groove 4 is formed in the friction surface 21 of the lining 2, the collection groove 4 of the nozzle 100 is in fluid communication with: a conduit 41 distinct from the opening 45 and comprising a mouth 42, the conduit 41 having a first diameter DI over a major part 41.1 of its extent; and with a suction hole 5 distinct from the opening 45 and configured to be connected to a source of depression.

[0098] Thus, the nozzle is configured so that an air flow is created from the mouth 42, through the conduit 41 and the groove 4, an air flow which sucks the particles through the opening 45, towards a suction hole 5 connected to the vacuum source by a fluid connection 51.

[0099] It is possible according to examples, as for the groove formed in the friction surface, for the groove to have several suction holes 5, and / or several mouths 42. This is the case in the example of [Fig. 10], which represents a pair of nozzles 100, each arranged opposite an annular surface on one side and the other of a disc (not shown), each groove comprising two mouths 42 and a suction hole 5 connected by a fluid connection 51 to a source of depression. In this example, the suction hole 5 is located approximately in the middle of the nozzle while the two mouths 42 (and therefore the two conduits 41) are arranged at two opposite ends of the nozzle.

[0100] The capture nozzle 100 further comprises a blocking device 6 configured to prevent a body 8 of a dimension greater than a limit value Dm from penetrating into the conduit 41 via the mouth 42 of the nozzle 100, the limit value Dm being less than or equal to 90% of the first diameter DI. The blocking device 6 may be in accordance with the examples described above and illustrated in FIGS. 4 to 8. The same technical benefits are obtained for the nozzle as for the plate described above, depending on whether one or other of the blocking devices 6 illustrated in FIGS. 4 to 8 is adopted.

[0101] Although these different examples have been described in separate ways, it is possible according to the present disclosure to combine them with each other. In particular, although they are not shown, it is possible to envisage examples in which the blocking device 6 comprises both an obstruction element 61 and / or a grid 62 and / or a reduced portion 44.

Claims

Claims

1. Brake pad (1) comprising a shoe (3) and a lining (2) supported on the shoe (3), the lining (2) comprising a friction surface (21) capable of coming into contact with a rotor (11) and a collection groove (4) for braking particles open on the friction surface (21), said collection groove (4) being in fluid communication with: • a conduit (41) opening out of the friction surface at a mouth (42), the conduit (41) having a first diameter (Dl) over a major part (41.1) of its extent; and • a suction hole (5) capable of being connected to a pressure source, said plate (1) comprising a blocking device (6) configured to prevent a body (8) of a dimension greater than a limit value (Dm) from penetrating into the conduit (41) via the mouth (42), the limit value (Dm) being less than or equal to 90% of the first diameter (Dl).

2. A plate (1) according to claim 1, wherein the limit value is less than or equal to 70% of the first diameter.

3. Plate (1) according to claim 1 or 2, in which the limit value is less than or equal to 32%, preferably less than or equal to 16% of the first diameter.

4. Plate (1) according to one of claims 1 to 3, in which the first diameter is between 1 mm and 6 mm, the first diameter preferably being approximately 4 mm.

5. Plate (1) according to one of claims 1 to 4, in which the locking device (6) is fixed to the lining (2) or is a part integrally formed with the lining (2) or with the sole (3).

6. Plate (1) according to one of claims 1 to 5, in which the blocking device (6) comprises an obstruction element (61) arranged opposite the mouth (42) and at a distance therefrom equal to the limit value (Dm).

7. Plate (1) according to the preceding claim, in which the obstruction element (61) is integral with the sole (3), preferably the obstruction element (61) is a U-shaped extension of the sole (3).

8. Plate (1) according to one of claims 1 to 7, in which the locking device (6) comprises a grid (62) arranged around said mouth (42).

9. Plate (1) according to the preceding claim, in which the grid (62) is integral with an insert (63) crossed by a channel (65) and attached to the conduit (41).

10. Plate (1) according to claim 8, in which said mouth (42) opens through an outer surface (43) of the plate (1), the grid (62) being attached to said outer surface (43) covering said mouth (42), preferably the grid (62) is welded to said outer surface (43).

11. Plate (1) according to one of claims 1 to 10, in which the mouth (42) has a second diameter less in particular by at least 10% than the first diameter of the conduit (41), the mouth (42) forming all or part of the blocking device.

12. Plate (1) according to one of claims 1 to 11, in which the conduit (41) comprises, in addition to the major part (41.1) defining the first diameter (Dl), a portion of reduced section (44) preferably conical, extending from the major part (41.1) to the mouth (42).

13. Nozzle (100) for capturing braking particles comprising: • a collection groove (4) configured to be positioned opposite a brake rotor (10); • a conduit (41), fluidly connected to the collection groove (4) and comprising a mouth (42), the conduit (41) having a first diameter (Dl) over a major part (41.1) of its extent; and • a suction hole (5) configured to be connected to a vacuum source, said nozzle (100) comprising a blocking device (6) configured to prevent a body (8) of a dimension greater than a limit value (Dm) from entering the conduit (41) via the mouth (42), the limit value (Dm) being less than or equal to 90% of the first diameter (Dl).

14. A particle capture nozzle (100) according to claim 13, wherein the limit value (Dm) is less than or equal to 70% of the first diameter.

15. Particle capture nozzle (100) according to one of claims 13 or 14, in which the limit value is less than or equal to 32%, preferably less than or equal to 16% of the first diameter.

16. Particle capture nozzle (100) according to one of claims 13 to 15, in which the first diameter is between 1 mm and 6 mm, the first diameter preferably being approximately 4 mm.

17. Particle capture nozzle (100) according to one of claims 13 to 16 in which the blocking device (6) comprises an obstruction element (61) arranged opposite the mouth (42) and at a distance therefrom equal to the limit value (Dm).

18. Particle capture nozzle (100) according to one of claims 13 to 17, in which the blocking device (6) comprises a grid (62) arranged around said mouth (42).

19. Particle capture nozzle (100) according to one of claims 13 to 18, in which the grid (62) is integral with an insert (63) crossed by a channel (65) and attached to the conduit (41).

20. Particle capture nozzle (100) according to one of claims 13 to 19, in which the mouth (42) has a second diameter which is in particular at least 10% smaller than the first diameter of the conduit (41), the mouth (42) forming all or part of the blocking device.

21. Particle capture nozzle (100) according to one of claims 13 to 20, in which the conduit (41) comprises, in addition to the major part (41.1) defining the first diameter (D1), a portion of reduced section (44) preferably conical, extending from the major part (41.1) to the mouth (42).

22. Braking system (10) comprising a rotor (11) and: • a pair of pads (1) according to one of claims 1 to 12; • and / or one or more particle capture nozzles (100) according to one of claims 13 to 21, the braking system (10) further comprising a source of depression fluidly connected to the suction hole (5) of the grooves (4) of each pad (1) and / or of each capture nozzle (100).

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