Brake pad for a disc brake of a rail vehicle and disc brake

Abstract

Brake pad (3) for a disc brake (1) of a rail vehicle, comprising - a carrier plate (4) essentially in the shape of a circular segment, - at least one lining carrier (5) held on the carrier plate (4), - at least one friction lining (6) attached to the lining carrier (5), characterized in that - the carrier plate (4) extends in the circumferential direction over an angle of at least 175° and up to 250°.

Description

[0001] The present invention relates to a brake pad for a disc brake of a rail vehicle according to the preamble of claim 1. The invention further relates to a disc brake of a rail vehicle with such a brake pad.

[0002] Generic brake pads are known, for example, from DE 10 2014 119 489 A1, EP 0784761 A1, EP 2 662 586 A1, EP 2 713 075 A1, JP 2010-270 826 A, DE 10 2014 119 492 A1, or WO 2016 / 027860 A1. These brake pads, which essentially consist of a circular ring-segment-shaped carrier plate and several lining carriers movably held thereon with friction linings attached thereto, are typically made of organic material or sintered metals.

[0003] During a rail vehicle's braking action, organic friction linings can absorb approximately 5% of the kinetic energy to be converted, and sintered friction linings approximately 10%. The majority of the heat energy released must be stored in the brake disc without exceeding the permissible temperature on the brake disc surface.

[0004] The amount of energy released into the environment by radiation or convection during such a braking action can be almost neglected.

[0005] From WO 2022 / 014712 A1 and EP 2 088 050 A2, brake pads are known in which the thickness of the pad carrier is greater than the thickness of the friction pads.

[0006] The object of the present invention is to provide a brake pad for a disc brake of a rail vehicle which is capable of absorbing the largest possible proportion of the released heat energy.

[0007] The stated object is achieved by a brake pad for a disc brake of a rail vehicle having the features of claim 1.

[0008] The stated object is further achieved by a disc brake of a rail vehicle having the features of claim 15.

[0009] The brake pad according to the invention for a disc brake of a rail vehicle has a carrier plate substantially in the shape of a circular ring segment, as well as at least one pad carrier held on the carrier plate and at least one friction pad fastened to the pad carrier.

[0010] The carrier plate extends in the circumferential direction over an angle of at least 175° and up to 250°.

[0011] The extension of the carrier plate and the associated enlargement of the friction surface enables a simple reduction in thermal resistance and thus an improved thermal conductivity of the brake pad to transport the friction energy generated during braking into the pad carrier.

[0012] A brake pad designed in this way, used in a rail vehicle disc brake, can be used advantageously in a variety of ways.

[0013] This means that the number of brake discs and associated brake pads can be reduced overall due to the improved heat absorption capacity, which has the further advantage of reducing unsprung masses and the total vehicle mass.

[0014] With the increased performance of the brake due to the thermal relief, it is also possible to use lighter brake discs, for example brake discs made of aluminum or brake discs with reduced dimensions, which also leads to a reduction in the unsprung masses.

[0015] Furthermore, grey cast iron brake discs can be used instead of the usual cast steel brake discs, which results in a considerable reduction in costs.

[0016] Furthermore, the use of brake pads according to the invention makes it possible to increase the vehicle's payload, which is accompanied by improved vehicle performance. It is also conceivable that the vehicle speed could be increased due to the improved performance of the brake pads and the disc brake.

[0017] Finally, the thermal relief of the brake disc achieved by the brake pad according to the invention enables a reduction in the life cycle costs of the disc brake.

[0018] Advantageous embodiments of the invention are the subject of the subclaims.

[0019] According to an advantageous embodiment, the carrier plate extends in the circumferential direction over an angle of 180°, which results in a further increase in the covering surface and the resulting advantages mentioned above.

[0020] Preferably, the thickness of the lining carrier is greater than the thickness of the unworn friction lining; according to an advantageous embodiment, this thickness is more than twice the thickness of the unworn friction lining, which entails an optimization of the thermal capacity of the lining carrier.

[0021] The increased thickness of the lining carrier (compared to conventional lining carrier thicknesses known from the prior art) also allows for an increase in the brake pad's thermal capacity. The friction lining is preferably divided into several friction lining segments.

[0022] According to another advantageous design variant, the lining carrier is made of aluminum. Aluminum, while being lightweight, has a high specific heat capacity and very good thermal conductivity.

[0023] According to a further advantageous embodiment of the brake pad according to the invention, several pad carriers, each with a friction pad attached thereto, are held on the carrier plate.

[0024] In a preferred embodiment, each of the lining carriers and the friction lining attached thereto extends in the circumferential direction over an angle of approximately 45°.

[0025] The division of the lining carrier into several lining carriers that are attached to the carrier plate enables a reduction in the curvature of the overall surface.

[0026] For this purpose, according to a further advantageous embodiment, the lining carrier also has several grooves.

[0027] In an advantageous embodiment, these grooves are incorporated in a surface of the lining carrier facing the carrier plate.

[0028] The grooves serve in particular to make the pad carrier more flexible in order to reduce the warping of the brake pad due to the one-sided thermal load on the brake pad.

[0029] In an alternative advantageous embodiment, the grooves extend from a friction surface of the friction lining to a surface of the lining carrier facing the friction lining.

[0030] The grooves on this side of the brake pad enable, in particular, a reduction in the curvature of the overall surface by dividing the friction surface into several individual surfaces.

[0031] According to a further embodiment variant, first grooves extend radially to an imaginary origin of the circular ring segment-shaped carrier plate.

[0032] In a further advantageous embodiment, second grooves extend tangentially or concentrically to the imaginary origin of the circular ring segment-shaped support plate.

[0033] According to a further alternative embodiment of a brake pad according to the invention, the pad has a plurality of at least nine pad carriers, each with a friction pad attached thereto, which are elastically mounted on the carrier plate.

[0034] In this brake pad, a fastening pin is preferably attached to each of the pad carriers, which is held movable, in particular pivotable, on the carrier plate via a tension spring supported in a recess in the carrier plate.

[0035] The disc brake of a rail vehicle according to the invention comprises a brake caliper with at least one brake pad holder and at least one brake pad arranged thereon. The brake pad is designed as described above.

[0036] In one embodiment, the carrier plate of the brake pad is formed in one piece with the brake pad holder 8, which enables an even more direct energy transport between the carrier plate and the brake pad holder and further facilitates the assembly of the disc brake.

[0037] Preferred embodiments are explained in more detail below with reference to the accompanying drawings. They show: They show: Fig. 1 a schematic perspective view of an embodiment of a disc brake according to the invention with a brake pad arranged on a brake caliper, Fig. 2 a perspective view of a first embodiment of a brake pad according to the invention with four pad carrier segments fixed to the carrier plate, Fig. 3 a perspective view of one of the lining carrier segments with grooves in the lining carrier, Fig. 4 an alternative embodiment of a brake pad according to the invention with grooves in the friction lining and in the lining carrier, Fig. 5 a detailed view of a segment of a lining carrier with a friction lining arranged thereon, divided by grooves and a plurality of friction lining segments, Fig. 6 and Fig. 7 den Fig. 4 and Fig. 5 corresponding representations with second grooves introduced tangentially instead of concentrically to an origin of the circular ring segment-shaped support plate, Fig. 8 one of the Fig. 4 corresponding representation of a further embodiment variant of a brake pad according to the invention with a plurality of pad carriers arranged on the carrier plate and Fig. 9 a sectional view through the brake pad according to Fig. 8 showing the elastic fixation of one of the lining carriers to the carrier plate.

[0038] In the following description of the figures, terms such as top, bottom, left, right, front, rear, etc., refer exclusively to the exemplary representation and position of the brake pad, carrier plate, pad carrier, friction lining, and the like chosen in the respective figures. These terms are not to be understood as limiting; i.e., these references may change due to different operating positions or the mirror-symmetrical design, etc.

[0039] In Fig. 1, the reference numeral 1 denotes an embodiment variant of a disc brake of a rail vehicle according to the invention.

[0040] The disc brake 1 has a brake disc 2, which is gripped by a brake caliper 7. The caliper levers of the brake caliper 7 are actuated pneumatically, hydraulically, or by an electric motor. At the front end of each caliper lever, a brake pad holder 8 is arranged, to which a brake pad 3 is attached.

[0041] Design variants of such a brake pad 3 are shown in the Fig. 2-9.

[0042] Common to the different design variants of brake pads 3 is a substantially circular ring-segment-shaped carrier plate 4, at least one lining carrier 5 held on the carrier plate 4 and at least one friction lining 6 fastened to the lining carrier 5.

[0043] The carrier plate 4 extends in the circumferential direction over an angular range of at least 175° and up to 250°.

[0044] Alternatively or additionally, the thickness d B of the lining carrier 5 greater than the thickness dR of the unworn friction lining 6, as shown for example in the Fig. 3 and Fig. 9 is illustrated.

[0045] A first embodiment of such a brake pad 3 is shown in Fig. 2 shown.

[0046] In this brake pad 3, the carrier plate 4 extends circumferentially over an angle of 180°. The surface of the carrier plate 4, which is aligned parallel to a friction surface 21 of the brake disc 2, is covered by four equally sized segments of a pad carrier 5 in this embodiment of the brake pad 3.

[0047] A single segment of such a lining carrier 5 is in Fig. 3. As shown here, the lining carriers 5 and the friction lining 6, which is formed on the same surface and attached to the respective lining carrier 5, extend in the circumferential direction over an angle of approximately 45°, in order to cover the entire surface of the carrier plate 4 when lined up one after the other, as shown in Fig. 2. The friction surface 63 of each of the friction linings 6 is designed to have a smooth surface in this embodiment.

[0048] How to continue in the Fig. 2 and Fig. 3, the thickness d B of the lining carrier 5 greater than the thickness d R of the unworn friction lining 6. By reducing the thickness d R of the unworn friction lining 6, there is a significant reduction in the thermal resistance of the friction lining 6 and thus a transfer of the thermal energy generated during a braking operation from the brake disc 2 into the lining carrier 5 of the brake lining 3 is facilitated.

[0049] The thickness of the B of the lining carrier 5 is preferably more than twice as thick as the thickness d R of the unworn friction lining 6.

[0050] How to continue in the Fig. 2 and Fig. 3, a plurality of grooves 51, 52 are provided in a surface of the lining carrier 5 facing the carrier plate 4. First grooves 51 extend radially to an imaginary origin U of the circular ring-segment-shaped carrier plate 4. Second grooves 52 extend concentrically to the imaginary origin U of the circular ring-segment-shaped carrier plate 4.

[0051] The intersecting grooves 51, 52 make it possible to make the pad carrier 5 more flexible, thus more easily counteracting the warping of the brake pad 3 due to the one-sided thermal load on the brake pad 3 during braking. The pad carrier 5 is preferably screwed to the carrier plate 4 by means of threaded holes 53 in the respective segments of the pad carrier 5 created by the grooves 51, 52.

[0052] On the side of the support plate 4 facing away from the lining carrier 5, as shown in the Fig. 1 and Fig. 2, the brake pad holder 8 is fastened, in particular screwed, which together with a crosspiece 9 connects the ends of the caliper lever halves of the brake caliper 7 to one another and thus ensures a uniform transmission of force to the brake pad 4.

[0053] As in Fig. 1, two such brake pad holders 8 are mounted on the carrier plate 4 due to the carrier plate 4 extending over an angle of 180° in the circumferential direction, wherein the ends of the transverse web 9 are mounted approximately centrally (viewed in the longitudinal direction of the brake pad holders 8) on the web-like brake pad holders 8 in holders of the brake pad holders 8 provided for this purpose.

[0054] It is also conceivable to form the carrier plate 4 of the brake pad 3 in one piece with the brake pad holder 8.

[0055] In one in the Fig. 4 and Fig. In the alternative embodiment of the brake pad 3 shown in Figure 5, the first grooves 51, 61 and second grooves 52, 62 are introduced from the friction lining side of the brake pad 3 into the friction lining 6 and the pad carrier 5. Accordingly, the grooves 51, 52, 61, 62 extend from a friction surface 63 of the friction lining 6 into a surface of the pad carrier 5 facing the friction lining 6.

[0056] Here too, the first grooves 51 are aligned radially to the origin of the circular ring-segment-shaped support plate 4 and the second grooves 52, 62 are aligned concentrically to the imaginary origin U of the circular ring-segment-shaped support plate 4.

[0057] In the Fig. 6 and Fig. In another embodiment of the brake pad 3, the grooves are tangentially aligned instead of concentrically aligned second grooves 52, 62. Tangentially aligned second grooves 52, 62 are understood here to be grooves that are aligned parallel to a tangent on the outer circumference of the respective segment of the pad carrier 5, perpendicular to a radial line that runs centrally through the respective segment of the pad carrier 5.

[0058] In the Fig. 8 and Fig. Figure 9 shows yet another embodiment of a brake pad 3, in which, instead of the four lining carriers 5 arranged side by side in the previous embodiments, a plurality of lining carriers 5 are arranged, here in two concentric rows, a total of twenty lining carriers 5 with friction linings 6 fixed thereto. Each of these lining carriers 5 is movable, in particular pivotally mounted, on the carrier plate 4 via a single fastening pin 10.

[0059] A tension spring 11, shown in Fig. 9. The tension spring 11 is arranged between the lining carrier 5 and the carrier plate 4. In this design variant, the thickness d R of the respective friction lining 6 is significantly less than the thickness d B of the lining carrier 5 holding the respective friction lining 6.

[0060] The lining carrier(s) 5 are preferably made of a material with higher specific thermal conductivity and specific heat capacity than the friction material, for example aluminum.

[0061] What all brake pads have in common is that due to the small thickness of the friction lining 6 relative to the lining carrier 5, the friction energy generated during braking can be transported from the brake disc to the lining carrier 5 as quickly as possible and with little resistance.

[0062] It is also conceivable to design the brake pad 3 in such a way that its circumferential dimensions correspond to the dimensions of conventional brake pads which cover an angle of 90° - 120° in the circumferential direction, since the reduced thickness of the friction pad 6 already transports the resulting friction energy quickly and with little resistance away from the brake disc 2 into the pad carrier 5.

[0063] Conversely, it is also conceivable to maintain the thickness of the friction lining 6 as in the prior art, since the larger friction lining surface also allows a reduction in thermal resistance. LIST OF REFERENCE SYMBOLS 1 disc brake 2 brake discs 21 Friction surface 3 brake pad 4 carrier plate 41 Recess 5 lining carriers 51 first groove 52 second groove 53 threaded hole 6 Friction lining 61 first groove 62 second groove 63 Friction surface 7 brake caliper 8 brake pad holders 9 Crossbar 10 mounting pins 11 Tension spring d R Thickness of the friction lining d B Thickness of the lining carrier U Origin

Claims

[1] Brake pad (3) for a disc brake (1) of a rail vehicle, comprising - a carrier plate (4) essentially in the shape of a circular segment, - at least one lining carrier (5) held on the carrier plate (4), - at least one friction lining (6) attached to the lining carrier (5), characterized by , that - the carrier plate (4) extends in the circumferential direction over an angle of at least 175° and up to 250°. [2] Brake pad according to claim 1, characterized by that the carrier plate (4) extends in the circumferential direction over an angle of 180°. [3] Brake pad according to claim 1 or 2, characterized by that the thickness (d B ) of the lining carrier (5) is greater than the thickness (d R ) of the unworn friction lining (6), in particular more than twice the thickness (d R ) of the unworn friction lining. [4] Brake pad according to one of the preceding claims, characterized bythat the friction lining (6) is divided into several friction lining segments. [5] Brake pad according to one of the preceding claims, characterized by that the lining carrier (5) is made of a material with higher specific thermal conductivity and specific heat capacity than the friction material. [6] Brake pad according to one of the preceding claims, characterized by that several lining carriers (5), each with a friction lining (6) attached to it, are held on the carrier plate (4). [7] Brake pad according to claim 6, characterized by that each of the lining carriers (5) and the friction lining (6) attached thereto extends in the circumferential direction over an angle of approximately 45°. [8] Brake pad according to claim 6 or 7, characterized by that each of the lining carriers (5) has several grooves (51, 52). [9] Brake pad according to claim 8, characterized bythat the grooves (51, 52) are introduced into a surface of the lining carrier (5) facing the carrier plate (4). [10] Brake pad according to claim 8, characterized by that the grooves (51, 52, 61, 62) extend from a friction surface (63) of the friction lining (6) into a surface of the lining carrier (5) facing the friction lining (6). [11] Brake pad according to one of claims 8 to 10, characterized by that first grooves (51, 61) extend radially to an imaginary origin (U) of the circular ring segment-shaped carrier plate (4). [12] Brake pad according to one of claims 8 to 11, characterized by that second grooves (52, 62) extend tangentially or concentrically to the imaginary origin (U) of the circular ring segment-shaped support plate (4). [13] Brake pad according to claim 6, characterized by that a plurality of at least nine lining carriers (5), each with a friction lining (6) attached thereto, are elastically mounted on the carrier plate (4). [14] Brake pad according to claim 13, characterized by that a fastening pin (10) is fastened to each of the lining carriers (5), which pre-tensions a tension spring between the lining carrier (5) and the carrier plate (4), whereby the lining carrier (5) is held movably, in particular pivotably, on the carrier plate (4). [15] Disc brake (1) of a rail vehicle, with a brake calliper (7) with at least one brake pad holder (8) and at least one brake pad (3) arranged thereon, characterized by that the brake pad (3) is designed according to one of the preceding claims. [16] Disc brake (1) according to claim 15, characterized by that the carrier plate (4) of the brake pad (3) is formed integrally with the brake pad holder (8).

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