Band spring and brake pad assembly, brake caliper, brake pad

Abstract

This invention describes a disc spring and brake pad assembly for a brake caliper, which focuses on improving the release of the brake pad from the brake disc. The assembly comprises a brake pad with a plate and friction material, and a disc spring with a clutch section and a spring pressure section. The pressure section contacts the brake pad on an inclined surface and exerts an elastic preload to retract the pad. The ramp is inclined axially and radially and extends from an inner to an outer edge. The outer edge comprises a convex section with a central portion and side sections. The disc spring applies preload primarily to the central portion of the convex section, ensuring that the brake pad moves away from the disc in both axial and radial directions. This design minimizes contact with the side sections of the convex portion and optimizes the retraction mechanism.

Description

Field of the invention

[0001] The present invention relates to a band spring and brake pad arrangement as well as a brake caliper and a brake pad. Background state of the art

[0002] In a disc brake, the brake caliper is generally arranged spanning the outer peripheral edge of a brake disc and is adapted to rotate about an axis of rotation (XX) which defines an axial direction (AA). In a brake disc, a radial direction (RR) which is substantially orthogonal to the axial direction (AA), a tangential direction (CC) which is orthogonal to both the axial direction (AA) and the radial direction (RR), as well as a circumferential direction (TT) which is locally or rather point-wise, i.e., at an intersection point of an axial and a radial direction, orthogonal to both the axial direction (AA) and the radial direction (RR) are also defined.

[0003] As is known, disc brake discs comprise a bell designed to associate the disc with a hub of a vehicle, from which extends an annular portion called a brake band, intended to cooperate with brake pads of a brake caliper.

[0004] Disc brake springs are known which consist of a central portion and two end portions, wherein the end portions bear against the pads to elastically bias the pads away from each other to ensure separation of the pads from the brake disc after each braking operation. According to one known type of such springs, the central portion of the springs is attached to the brake caliper, thereby holding the spring in its operating position. Such known springs are used to reduce brake pad vibration; separate the pads from the brake disc to reduce or eliminate residual braking torque (residual torque) due to unwanted contact between the pads and the brake disc when the brake is deactivated; and achieve even wear of the brake pad friction linings.

[0005] In particular, the prior art springs generally include one or more connecting legs formed at the central portion of the spring and configured to connect the springs to the brake caliper.

[0006] For example, springs are known that are connected to the brake caliper body so as to span the brake disc in two tangentially opposite portions to preload the brake pad at two opposite lateral portions thereof. This type of spring is known from documents WO2019 / 243958 and WO2020 / 128710, which use at least two springs connected by elastic interference to, and interposed between, a first side bridge of the brake caliper body and at least one central bridge of the brake caliper body, respectively, and a second side bridge of the brake caliper body and the at least one central bridge of the brake caliper body. Such springs contact a radially outer edge of the brake pad plate at the respective lateral ears of the brake pad.These solutions, although satisfactory, are cumbersome as they involve the use of two springs acting on diametrically opposed ears of the brake pad.

[0007] Therefore, there is a need in the industry to provide spring and brake pad solutions that enable a reduction in weight and size compared to the state of the art, thus allowing the production of more compact and lighter brake caliper bodies, while the spring-pad interaction characteristics remain essentially unchanged, if not improved.

[0008] Other solutions for springs and spring / brake pad assemblies are known, for example, from document WO201118815. This discloses the use of at least one spring contacting a central portion of the brake pad at an upper or radially outer edge thereof. While satisfactory in many respects, it has been found that the curved configuration of this spring, in combination with the contact portion of the brake pad, generates high friction, which reduces the efficiency of detaching the brake pad from the brake disc and thus impairs the reduction and / or elimination of residual torque.

[0009] Therefore, there is a need in the industry to produce brake springs and pads that allow a reduction in their dimensions, thus allowing more compact caliper bodies to be produced without compromising the resulting deformation of the caliper body, enabling safe and reliable positioning of the spring on the brake pad while also enabling low-friction sliding between the spring and brake pad compared to the state of the art. Solution

[0010] The present invention aims to provide a band spring and brake pad assembly which enables low-friction sliding between the spring and the brake pad.

[0011] These and other objects and advantages are achieved by a band spring and brake pad assembly according to claim 1, a brake caliper according to claim 11 and a brake pad according to claim 13.

[0012] Some advantageous embodiments are the subject of the dependent claims.

[0013] The proposed solutions make it possible to reduce the number of band springs used to elastically preload the brake pads, while maintaining the excellent properties of retraction of the brake pad from the disc by reducing or even eliminating any residual torque at the end of the braking action.

[0014] In addition, the proposed solutions can reduce the weight and size of a brake pad and a brake caliper compared to the state of the art.

[0015] In addition, the proposed brake pad and band spring geometries can facilitate the installation of the band spring on the brake pad through a self-centering coupling.

[0016] In addition, due to the proposed geometries of the brake pad and band spring, it is possible to limit the contact and sliding zones of the brake pad and band spring to a minimum of one contact and sliding zone up to a maximum of two contact and sliding zones, which allows for a very responsive retraction of the brake pad with respect to the brake disc. Drawings

[0017] Furthermore, features and advantages of the band spring and brake pad assembly, the brake caliper and the brake pad will become apparent from the following description of preferred embodiments thereof, given by way of non-limiting indications with reference to the accompanying drawings, in which: - Fig. Figure 1 is an axonometric view of a brake caliper according to a first embodiment in which a band spring and brake pad assembly according to the present invention is provided, in particular with a single band spring cooperating with two opposing brake pads, the band spring being connected to the brake caliper body only at two central axial tie rods; - Fig. 2 a top view of the brake calliper in Fig. 1 is; - Fig. 3 is an axonometric view of a band spring of the band spring and brake pad assembly according to the present invention, which is adapted to be inserted in the brake caliper in Fig. 1 to be used; - Fig. 4 a side view of the band spring in Fig. 3, in which the shaped spring thrust section with two U- or V-shaped branches can be seen; - Fig. 5 is a front view of a brake pad of the band spring and brake pad assembly according to the present invention according to a first embodiment, wherein the brake pad comprises a single thrust portion adapted to slide and contact the band spring according to the embodiments of the present invention, wherein the thrust portion is curved and has a radially outer maximum such that the spring contacts the brake pad only at this radially outer maximum to retract the brake pad in the absence of braking action; - Fig. 6 a partially sectioned front view of the brake calliper in Fig. 1 is in which the brake pad in Fig. 5, which is connected to the ribbon spring in Fig. 3, wherein four coupling arms are coupled in pairs to two axial tie rods of the caliper body; - Fig. 7 a front view from the back of the brake pad of the band spring and brake pad assembly in Fig. 6, in which thrust elements or pistons of the brake caliper are shown; - the Fig. 8, Fig. 9 and Fig. 10 are cross-sections of the band spring and brake pad assembly, taken along the section planes JJ, KK and HH, to show that the band spring and the brake pad are in contact only in a central part of the spring thrust end and a central part of the plate thrust section; - Fig. 11 is a front view of a brake pad of the band spring and brake pad assembly according to the present invention according to a second embodiment, wherein the brake pad comprises a single thrust portion adapted to slide and contact the band spring according to the embodiments of the present invention, wherein the thrust portion has a profile forming a recess between two convex portions, wherein the band spring is adapted to contact the thrust portion in two diametrically opposed contact zones within the recess with two diametrically opposed edges; - Fig. 12 a partially sectioned front view of the brake caliper in Fig. 1 is in which the brake pad in Fig. 11, which is coupled to a band spring having only two coupling arms coupled to respective axial tie rods of the caliper body; - Fig. 13 a front view from the back of the brake pad of the band spring and brake pad assembly in Fig. 12, showing thrust elements or pistons of the brake caliper; - the Fig. 14, Fig. 15 and Fig. 16 are cross-sections of the band spring and brake pad assembly, taken along section planes JJ, KK and HH, to show that the band spring and the brake pad are in contact in two contact zones, thereby preventing the band spring and the brake pad from coming into contact with central portions of the spring thrust section and the plate thrust section; - Fig. 17 a partially sectioned front view of the brake caliper in Fig. 1, in which a brake pad according to a third embodiment can be seen, wherein the thrust portion of the brake pad in the center of gravity of the brake pad is made as a continuous window passing through the plate and the friction material and is closed on four sides, wherein the thrust portion has the same profile as the thrust portion of the brake pad shown in Fig. 5 shown brake pad; - Fig. 18 a partially sectioned front view of the brake caliper in Fig. 1, in which a brake pad according to a fourth embodiment can be seen, wherein the thrust section of the brake pad in the center of gravity of the brake pad is made as a continuous window passing through the disc and the friction material and is closed on four sides, wherein the thrust section has the same profile as the thrust section of the brake pad shown in Fig. 11 shown brake pad; - Fig. 19 is an axonometric view of a brake caliper according to a first embodiment, providing a band spring and brake pad assembly according to the present invention, in particular comprising a single band spring cooperating with two opposing brake pads, the band spring being connected to a tangential tie rod of the caliper body, the band spring being made from a single spring band; - Fig. 20 a top view of the brake calliper in Fig. 19 is; - Fig. 21 is an axonometric view of a band spring of the band spring and brake pad assembly according to the present invention, which is adapted to be inserted into the brake caliper in Fig. 19 to be used. Description of some preferred embodiments

[0018] According to a general embodiment, a band spring and brake pad arrangement for a brake caliper 6 is identified as a whole by the reference numeral 1.

[0019] The arrangement 1 defines an axial direction AA, a radial direction RR perpendicular to the axial direction AA, and a tangential direction CC perpendicular to the axial direction AA and the radial direction RR. In this description, unless otherwise specified, the axial direction AA, the radial direction RR, and the tangential direction CC may be understood to mean directions coincident with or parallel to them.

[0020] The assembly 1 comprises a brake pad 5 comprising a plate 10 and a friction material 11 supported by the plate 10. The friction material 11 is configured to contact a braking surface 4 of a brake disc 3. The brake disc 3 has an axis of rotation XX around which it rotates, the axis of rotation XX running parallel to the axial direction AA.

[0021] The plate 10 comprises a first tangential outer edge 14 and a second tangential outer edge 15, which are diametrically opposite or mirrored with respect to a centerline plane AR. The centerline plane AR is parallel to the axial direction AA and the radial direction RR. According to one embodiment, the first tangential outer edge 14 and the second tangential outer edge 15 extend substantially linearly in the radial direction RR.

[0022] The plate 10 comprises a radially outer edge 16 and a radially inner edge 17. The radially outer edge 16 points at least partially along the radial direction RR radially outward RO away from the rotation axis XX. The radially inner edge 17 points at least partially along the radial direction RR radially inward RI in the direction of the rotation axis XX. The radially outer edge 16 comprises a thrust portion 12.

[0023] The assembly 1 comprises a band spring 2. The band spring 2 comprises a coupling portion 8 configured to be connected to a brake caliper body 7, at least one spring thrust portion 9 configured to contact the brake pad 5 at the thrust portion 12 to exert an elastic preload on the brake pad 5 to move it away from the brake disc 3, wherein the spring thrust portion 9 is coupled to the coupling portion 8. According to one embodiment, a band spring 2 is shaped such that it is arranged spanning a brake disc 3 to exert the elastic preload on at least one brake pad 5 to bias it away from the brake disc 3.

[0024] The thrust section 12 is delimited by at least one ramp 18. The ramp 18 is inclined at least with respect to the axial direction AA and the radial direction RR. The ramp 18 faces the same side as the friction material 11.

[0025] The ramp 18 extends radially and axially away from the friction material 11 between a radially inner edge 19 and a radially outer edge 20, the radially outer edge 20 extending at least in the radial direction RR and at least in the tangential direction CC crossing the centerline plane AR.

[0026] Advantageously, the radially outer edge 20 comprises at least a first convex portion 21. The first convex portion 21 forms a first concavity facing radially inward RI. The first convex portion 21 comprises a first central portion 22, a first side portion 23, and a second side portion 24. The first central portion 22 is interposed between the first side portion 23 and the second side portion 24.

[0027] Advantageously, the band spring 2 is configured to exert, with the spring thrust portion 9, the elastic preload at least partially on the first central portion 22 of the first convex portion 21, whereby the brake pad 5 is preloaded at least away from the brake disc 3 in the axial direction AA, thereby preventing contact with the first side portion 23 and the second side portion 24 of the first convex portion 21.

[0028] By means of the arrangement 1 according to the present invention, it is possible to limit the contact zones between the band spring 2 and the brake pad 5 as much as possible in order to enable a secure contact between the band spring and the brake pad and to allow the brake pad to move away from the brake disc as soon as the highly efficient braking action is terminated.

[0029] According to one embodiment, the radially outer edge 20 comprises at least one second convex portion 25 forming a second concavity facing radially inward RI. According to one embodiment, the radially outer edge 20 comprises at least one concave portion 29 forming a third concavity facing radially outward RO. According to one embodiment, the concave portion 29 is central with respect to the first convex portion 21 and the second convex portion 25, which are tangentially external with respect to the concave portion 29.

[0030] According to one embodiment, the spring thrust portion 9 exerts the elastic preload on the first convex portion 21 and the second convex portion 25, whereby the brake pad 5 is pressed at least away from the brake disc 3 in the axial direction AA, thereby preventing contact with the concave portion 29.

[0031] According to one embodiment, the second convex portion 25 comprises a second central part 26, a third side part 27 and a fourth side part 28, wherein the second central part 26 is inserted between the third side part 27 and the fourth side part 28.

[0032] According to one embodiment, the band spring 2 is configured to exert, with the spring thrust portion 9, the elastic preload at least partially on the second central portion 26 of the second convex portion 25, whereby the brake pad 5 is preloaded at least away from the brake disc 3 in the axial direction AA, thereby preventing contact with the third side portion 27 and the fourth side portion 28 of the second convex portion 25.

[0033] According to one embodiment, the spring thrust portion 9 exerts the elastic preload on the first convex portion 21 and the second convex portion 25, whereby the brake pad 5 is preloaded at least away from the brake disc 3 in the axial direction AA, whereby only the first convex portion 21 and the second convex portion 25 are contacted and any other contact of the brake pad 5 with the spring thrust portion 9 is prevented.

[0034] The band spring and brake pad arrangement 1 makes it possible to create only two contact and sliding zones between the brake pad and the band spring to allow retraction of the brake pad once the braking process is completed.

[0035] According to one embodiment, the band spring 2 is configured to exert the elastic preload on the brake pad 5 with the spring thrust section 9, whereby the brake pad 5 is preloaded away from the brake disc 3 at least in the axial direction AA and the brake pad 5 is preloaded in the radial direction RR.

[0036] According to one embodiment, the concave portion 29 is radially inward with respect to the first convex portion 21 and the second convex portion 25 where the concave portion 29 crosses the centerline plane AR.

[0037] According to one embodiment, the radially outer edge 20 extends along a longitudinal edge direction GG which is centrally U-shaped, at least partially inclined with respect to both the radial direction RR and the tangential direction CC, and laterally linear, parallel to the tangential direction CC.

[0038] According to one embodiment, the spring thrust section 9 comprises a first spring edge 30 and a second spring edge 31, which are tangentially opposite to each other. According to one embodiment, the spring thrust section 9 contacts the first convex section 21 with the first spring edge 30 and the second convex section 25 with the second spring edge 31.

[0039] According to one embodiment, the spring thrust section 9 comprises a radially inner surface 32 that faces radially inward RI in the direction of the brake pad 5. According to one embodiment, the radially inner surface 32 extends along the tangential direction CC between a first spring edge 33 and a second spring edge 34. According to one embodiment, the spring thrust section 9 contacts the first convex section 21 with the first spring edge 33 and the second convex section 25 with the second spring edge 34. According to one embodiment, the first spring edge 33 and the second spring edge 34 are rounded.

[0040] According to one embodiment, the spring thrust section 9 comprises a thrust end 35 configured to contact the brake pad 5, wherein the thrust end 35 defines a thrust section width 36. According to one embodiment, a first tangential distance along the tangential direction CC or a direction parallel thereto exists between the second side part 24 of the first convex section 21 and the fourth side part 28 of the second convex section 25. According to one embodiment, a second tangential distance along the tangential direction CC or a direction parallel thereto exists between the first side part 23 of the first convex section 21 and the third side part 27 of the second convex section 25.According to one embodiment, the thrust section width 36 is greater than the first tangential distance and less than the second interference distance, so that the thrust end 35 interferes with the first central part 22 and the second central part 27, centering itself with respect to the thrust section 12. According to one embodiment, the thrust section width 36 is equal to a central tangential distance running along the tangential direction CC between the first central part 22 and the second central part 27, so that the spring thrust section 9 centers itself on the thrust section 12.

[0041] Due to the contact between only two tangentially opposite zones of the spring thrust section 9 and the brake pad thrust section 12, it is possible to achieve a self-centering band spring on the brake pad, which allows for a greatly simplified assembly.

[0042] In addition, due to the contact between only two tangentially opposite zones of the spring thrust portion 9 and the brake pad thrust portion 12, it is possible to enable planar retraction of the brake pad, thereby preventing portions of the friction material from being worn differentially during retraction of the brake pad.

[0043] According to one embodiment, the first central part 22 is located radially outward with respect to the first side part 23 and the second side part 24. According to one embodiment, the first central part 22 is crossed by the centerline plane AR. According to one embodiment, the first central part 22 forms a radially outer apex portion of the radially outer edge 20. According to one embodiment, the first central part 22 is the radially outermost portion of the radially outer edge 20.

[0044] According to one embodiment, the band spring 2 is configured to exert the elastic preload with the spring thrust portion 9 only on the first central part 22 of the first convex portion 21, whereby the brake pad 5 is preloaded at least away from the brake disc 3 in the axial direction AA and in the radial direction RR.

[0045] According to one embodiment, the radially outer edge 20 comprises two concave sections 29 that are tangentially opposite with respect to the at least one first convex section 21, wherein the first convex section 21 is located radially outward with respect to the two concave sections 29. The strip spring 2 is configured to exert the elastic preload on the first convex section 21 with the spring thrust section 9, thereby preventing contact with the two concave sections 29.

[0046] According to one embodiment, the spring thrust section 9 comprises a thrust end 35 configured to contact the brake pad 5. The thrust end 35 defines a thrust section width 36. Each concave section 29 of the two concave sections 29 is substantially U-shaped. Each concave section 29 has a radial minimum, with a concave section spacing defined between the radial minima of the two concave sections 29, the thrust section width 36 being substantially equal to the concave section spacing.

[0047] Due to the provision of the thrust portion 12 of the brake pad 5, which comprises a central convex portion forming a radially outer maximum of the thrust portion 12, it is possible to limit the contact between the band spring 2 and the brake pad to a single contact and sliding zone, which enables excellent mutual contact and positioning of the band spring and the brake pad and enables extremely responsive movement of the brake pad away from the plate once the braking operation is completed.

[0048] According to one embodiment, the plate 10 includes a free front surface 37 around the friction material 11. The free front surface 37 faces the same side as the friction material 10.

[0049] According to one embodiment, the plate 10 comprises a rear side 38 that defines the plate 10 on the side axially opposite the friction material 11. The rear side 38 is configured to face the thrust elements 45 of the brake caliper 6.

[0050] According to one embodiment, the radially inner edge 19 is defined by the intersection point of the ramp 18 and the free front surface 37.

[0051] According to one embodiment, the thrust section 12 is delimited by an axial edge 39 extending along the axial direction AA between the ramp 18 and the rear side 38. According to one embodiment, the axial edge 39 extends linearly parallel to the axial direction AA.

[0052] According to one embodiment, the radially outer edge 20 is defined by the intersection of the ramp 18 and the axial edge 39.

[0053] According to one embodiment, the spring thrust section 9 comprises a thrust end 35 which is configured to come into contact with the brake pad 5, wherein the thrust end 35 is bent by a spring angle with respect to the radial direction RR in the opposite direction with respect to the brake pad 5, and wherein the ramp 18 is inclined by a ramp angle with respect to the radial direction RR, wherein the ramp angle is smaller than the spring angle in order to prevent contact between the ramp 18 and the band spring 2.

[0054] According to one embodiment, the radially inner edge 19 extends along a longitudinal direction parallel to the extension direction of the radially outer edge 20.

[0055] According to one embodiment, the plate 10 comprises a stop portion 13. According to one embodiment, the axial edge 38 forms the stop portion 13.

[0056] According to one embodiment, the strip spring 2 comprises a contact section 68 configured to bear against the stop section 13 by forming a support on a region of the stop section 13, preventing any slippage of the spring thrust section 9 when the strip spring 2 is subjected to external influences. According to one embodiment, the contact section 68 is preloaded such that it bends when it bears against the stop section 13. According to one embodiment, the contact section 68 extends cantilevered from the spring body 46.

[0057] According to one embodiment, the contact portion 68 never comes into contact with the stop portion 13 during operation. According to one embodiment, the contact portion 68 tends to move away from the stop portion 13 as the friction material wears progressively.

[0058] According to one embodiment, the plate 10 defines a spring housing 40 configured to receive the spring thrust section 9. The spring housing 40 extends through at least one plate thickness. The plate 10 comprises a first lateral receiving wall 41 and a second lateral receiving wall 42, which are connected to the thrust section 12 and extend from the thrust section 12 at least in the radial direction RR and tangentially delimit the spring housing 40 on opposite sides. According to this embodiment, the spring housing 40 is delimited radially inwardly RI along the radial direction RR by the thrust section 12.

[0059] According to one embodiment, the spring housing 40 is open radially outward RO in the radial direction RR.

[0060] According to one embodiment, the spring housing 40 is closed by a radially inner wall 43 which points radially inward RI.

[0061] According to one embodiment, the spring housing 40 is closed by a radially inner wall 43 facing radially inward RI, wherein the spring housing 40 passes through the brake pad 5 in order to arrange the thrust portion 12 close to a center of gravity of the friction material 10.

[0062] By positioning the thrust portion 12 of the brake pad 5 close to the center of gravity or thrust center of the brake pad 5, it is possible to apply the elastic force of the spring to the center of the brake band of the disc, enabling a very balanced retraction of the brake pad. Furthermore, it is possible to limit the deformation of the brake pad as much as possible.

[0063] According to one embodiment, the strip spring 2 comprises a spring body 46.

[0064] According to one embodiment, the coupling section 8 comprises at least a first coupling arm 47 and a second coupling arm 48, which are configured to couple the band spring 2 to the brake caliper body 6. Each coupling arm 47, 48 extends from a central spring section 50 to a respective coupling end 49.

[0065] According to one embodiment, the first coupling arm 47 and the second coupling arm 48 are bent substantially in a U-shape.

[0066] According to one embodiment, the strip spring 2 comprises at least one first thrust arm 51 extending from the central spring section 50 to the spring thrust section 9. According to one embodiment, the spring thrust section 9 has a respective thrust end 35. According to one embodiment, the at least one first thrust arm 51 is formed with two U- or V-shaped branches.

[0067] According to one embodiment, the first thrust arm 51 comprises a first flat thrust segment 54 extending mainly along the axial direction AA, a second flat thrust segment 55 connected to the first flat thrust segment 54 by means of a first curved thrust segment 52 such that the second flat thrust segment 55 is inclined with respect to the radial direction RR and is bent towards the central spring portion 50, and a third flat thrust segment 56 connected to the second flat thrust segment 55 by means of a second curved thrust segment 53 such that the third flat thrust segment 56 is inclined with respect to the radial direction RR and is bent towards the central spring portion 50.

[0068] According to one embodiment, the contact section 68 extends cantilevered from the first push arm 51 away from the spring push section 9.

[0069] According to one embodiment, the strip spring body 2 is obtained from a shaped and bent, punched sheet metal with a predetermined spring thickness, thereby forming a spring strip.

[0070] According to one embodiment, the coupling section 8 and the spring thrust section 9 are bent in orthogonal folding planes.

[0071] According to one embodiment, the coupling portion 8 is formed integrally with the spring thrust portion 9. For example, the coupling portion 8 is made as a tongue in the spring body 46, as shown in Fig. 21, wherein the tongue is in a lateral position with respect to the push section 9, or in Fig. 19, wherein the tongue is made in the band body of the push section 9, leaving a tongue opening.

[0072] According to one embodiment, the coupling section 8 and the spring thrust section 9 are bent on coincident or parallel folding planes. According to one embodiment, the first coupling arm 47 and the second coupling arm 48 are configured to engage around a tangential pull rod 63 that runs parallel to the brake disc 3. According to one embodiment, the band spring comprises the first coupling arm 47 and the second coupling arm 48 without additional coupling arms when the brake pad has the thrust section provided with two support zones, which enables a coupling between the band spring and the self-centering brake pad.

[0073] According to one embodiment, the band spring 2 comprises a first spring band 57 and a second spring band 58, which are connected to one another at the central spring section 50, wherein the first spring band 57 forms the spring thrust section 9 and the second spring band 58 forms the coupling section 8.

[0074] According to one embodiment, the coupling portion 8 comprises a third coupling arm 59 and a fourth coupling arm 60. According to one embodiment, the third coupling arm 59 cooperates with the first coupling arm 47 to fix the band spring 2 to a first axial tie rod 61 of the caliper body 6, which is positioned spanning the brake disc 3, and the fourth coupling arm 60 cooperates with the second coupling arm 48 to fix the band spring 2 to a second axial tie rod 62 of the caliper body 6, which is positioned spanning the brake disc 3. It is thus possible to center the band spring 2 with respect to the thrust portion 12 of the brake pad, which has a single convex portion forming a radially outer maximum, thereby obtaining a single contact zone between the brake pad 5 and the band spring 2.

[0075] According to one embodiment, the coupling section 8 and the spring thrust section 9 extend along mutually orthogonal directions. According to one embodiment, a tangential axial pull rod distance is defined between the first axial pull rod 61 and the second axial pull rod 62, wherein the tangential axial pull rod distance is measured with respect to a center of each axial pull rod 61, 62 or between respective surfaces or edges of the axial pull rods 61, 62 facing each other along the tangential direction CC. According to one embodiment, the tangential axial pull rod distance is between three and one and a half times the thrust section width 36 of the spring thrust section 9. According to one embodiment, the tangential axial pull rod distance is at a minimum equal to the thrust section width 36.

[0076] The present invention further relates to a brake caliper, which is identified by the reference numeral 6.

[0077] The brake caliper 6 comprises a brake caliper body 7, which is configured to span a brake disc 3. The brake caliper body 7 comprises a first elongate element 64, a second elongate element 65, a first connecting bridge 66, and a second connecting bridge 67, which connect the first elongate element 64 and the second elongate element 65 on tangentially opposite sides.

[0078] The brake caliper 6 comprises a band spring and brake pad arrangement 1 according to one of the previously described embodiments.

[0079] The brake pad 5 is held either directly or indirectly by the brake caliper body 7 and is received in the brake caliper body 7.

[0080] The brake caliper 6 comprises thrust elements or pistons 45 which are received in the first elongate element 64 and / or the second elongate element 65 in order to preload at least the brake pad 5 towards the brake disc 3.

[0081] According to one embodiment, the brake caliper 6 comprises a first axial pull rod 61 and a second axial pull rod 62 connecting the first elongate element 64 in the axial direction AA to the second elongate element 65, wherein the band spring 2 is preferably coupled as an undercut to the first axial pull rod 61 and the second axial pull rod 62, thereby preventing coupling to the first connecting bridge 66 and / or the second connecting bridge 67.

[0082] According to one embodiment, the first axial pull rod 61 and the second axial pull rod 62 have a tangential dimension of the axial pull rod or a tangential thickness 70 of the axial pull rod that is smaller than a thrust section width 36 of the thrust section 9. According to one embodiment, each tangential dimension of the axial pull rod or tangential thickness of the axial pull rod is measured as the distance between two tangentially opposite surfaces of the respective axial pull rod 61, 62, preferably between the zones in which the two tangentially opposite surfaces are further apart from each other.

[0083] According to one embodiment, the first axial tie rod 61 and the second axial tie rod 62 extend over the first elongate member 64 and the second elongate member 65 and form reinforcing ribs 72 in reinforcing planes parallel to the axial direction AA and to the radial direction RR.

[0084] According to one embodiment, the brake caliper 6 comprises a tangential tie rod 63 connecting the first connecting bridge 66 along the tangential direction CC to the second connecting bridge 67 located above the brake disc 3, wherein the band spring 2 is connected, preferably as an undercut, to the tangential tie rod 63.

[0085] According to one embodiment, the tangential pull rod 63 has an axial dimension of the tangential pull rod or an axial thickness 71 of the tangential pull rod that is smaller than a thrust section width 36 of the thrust section 9. According to one embodiment, the axial dimension of the tangential pull rod or the axial thickness 71 of the tangential pull rod is measured as the distance between two axially opposite surfaces of the tangential pull rod 63, preferably between the zones in which the two axially opposite surfaces are further apart from each other.

[0086] The present invention further relates to a brake pad, indicated by reference numeral 5. The brake pad 5 defines an axial direction AA, a radial direction RR perpendicular to the axial direction AA, and a tangential direction CC perpendicular to both the axial direction AA and the radial direction RR.

[0087] The brake pad 5 comprises a plate 10 and a friction material 11 held by the plate 10, wherein the friction material 11 is adapted to contact a braking surface 4 of a brake disc 3, wherein the brake disc 3 has an axis of rotation XX about which it rotates, wherein the axis of rotation XX is parallel to the axial direction AA.

[0088] The plate 10 comprises a first tangential outer edge 14 and a second tangential outer edge 15 which are diametrically opposite or mirrored with respect to a centerline plane AR, the centerline plane AR being parallel to the axial direction AA and the radial direction RR.

[0089] The plate 10 comprises a radially outer edge 16 and a radially inner edge 17, wherein the radially outer edge 16 points at least partially along the radial direction RR away from the axis of rotation XX radially outwards RO, wherein the radially inner edge 16 points at least partially along the radial direction RR in the direction of the axis of rotation XX radially inwards RI.

[0090] The radially outer edge 16 comprises a thrust portion 12 which is adapted to be contacted by a band spring 2 in order to receive an elastic preload away from the brake disc 3. The thrust portion 12 is delimited by at least one ramp 18, the ramp 18 being inclined at least with respect to the axial direction AA and the radial direction RR, the ramp 18 pointing to the same side as the friction material 11. The ramp 18 extends between a radially inner edge 19 and a radially outer edge 20 radially and axially away from the friction material 11. The radially outer edge 20 comprises at least one first convex portion 21, the first convex portion 21 forming a first concavity pointing radially inward RI.The first convex portion 21 comprises a first central part 22, a first side part 23 and a second side part 24, wherein the first central part 22 is inserted between the first side part 23 and the second side part 24, so that the band spring 2 is adapted to exert the elastic preload at least partially on the first central part 22 of the first convex portion 21, whereby the brake pad 5 is preloaded at least away from the brake disc 3 in the axial direction AA, while preventing contact with the first side part 23 and the second side part 24 of the first convex portion 21.

[0091] According to one embodiment, the brake pad 5 is the brake pad of the band spring and brake pad arrangement 1 described above. LIST OF REFERENCE SYMBOLS 1 Band spring and brake pad arrangement 2 band springs 3 brake disc 4 braking surface 5 brake pad 6 brake caliper 7 saddle body 8 Coupling section 9 flexible push section 10 plates 11 Friction material 12 thrust section 13 Stop section 14 first tangential outer edge 15 second tangential outer edge 16 radial outer edge 17 radial inner edge 18 Ramp 19 radial inner edge 20 radial outer edge 21 first convex section 22 first central section 23 first page 24 second side part 25 second convex section 26 second central section 27 third side panel 28 fourth side panel 29 concave section 30 first feather edge 31 second feather edge 32 radial inner surface 33 first spring edge or first radially inner shear section edge 34 second spring edge or second radially inner shear section edge 35 thrust ends 36 push section width 37 free front plate area 38 back of record 39 axial edge 40 spring housing 41 first side receiving wall 42 second side wall 43 radial inner wall 44 plate thickness 45 thrust elements or pistons 46 spring bodies 47 first coupling arm 48 second coupling arm 49 coupling ends 50 central spring section 51 first push arm 52 first curved thrust segment 53 second curved thrust segment 54 first flat thrust segment 55 second flat thrust segment 56 third flat thrust segment 57 first spring body band 58 second spring body band 59 third coupling arm 60 fourth coupling arm 61 first axial tie rod 62 second axial tie rod 63 tangential drawbar 64 first elongated element 65 second elongated element 66 first connecting bridge 67 second connecting bridge 68 Annex Section 69 Pad retaining and sliding pins XX Rotation axis AA axial direction RR radial direction CC tangential direction TT circumferential direction AR midline plane RI radially inward RO radially outwards GG longitudinal edge direction E spring angle F Ramp angle QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2019 / 243958

[0006] WO 2020 / 128710

[0006] WO 201118815

[0008]

Claims

[1] Band spring and brake pad assembly (1) for a brake caliper (6), the assembly (1) defining an axial direction (AA), a radial direction (RR) perpendicular to the axial direction (AA) and a tangential direction (CC) perpendicular to both the axial direction (AA) and the radial direction (RR), the assembly (1) comprising: - a brake pad (5) comprising a plate (10) and a friction material (11) held by the plate (10), wherein the friction material (11) is adapted to contact a braking surface (4) of a brake disc (3), wherein the brake disc (3) has an axis of rotation (XX) about which it rotates, wherein the axis of rotation (XX) is parallel to the axial direction (AA), wherein the plate (10) comprises a first tangential outer edge (14) and a second tangential outer edge (15) which are diametrically opposite or mirrored relative to a centerline plane (AR), the centerline plane (AR) being parallel to the axial direction (AA) and the radial direction (RR), wherein the plate (10) comprises a radially outer edge (16) and a radially inner edge (17), wherein the radially outer edge (16) points at least partially along the radial direction (RR) away from the axis of rotation (XX) radially outwards (RO), wherein the radially inner edge (17) points at least partially along the radial direction (RR) in the direction of the axis of rotation (XX) radially inwards (RI), wherein the radially outer edge (16) comprises a thrust portion (12), the assembly (1) comprising: - a band spring (2) comprising a coupling section (8) which is designed to connect to a brake caliper body (7) at least one spring thrust section (9) which is designed to contact the brake pad (5) at the thrust section (12) in order to exert an elastic preload on the brake pad (5) in order to move it away from the brake disc (3), wherein the spring thrust section (9) is connected to the coupling section (8), wherein the thrust section (12) is delimited by at least one ramp (18), wherein the ramp (18) is inclined at least relative to the axial direction (AA) and the radial direction (RR), wherein the ramp (18) points to the same side as the friction material (11), wherein the ramp (18) extends radially and axially away from the friction material (11) between a radially inner edge (19) and a radially outer edge (20), wherein the radially outer edge (20) extends crossing the center line plane (AR) at least in the radial direction (RR) and at least in the tangential direction (CC), wherein the radially outer edge (20) comprises at least a first convex portion (21), wherein the first convex portion (21) forms a first concavity facing radially inward (RI), wherein the first convex portion (21) comprises a first central part (22), a first side part (23) and a second side part (24), wherein the first central part (22) is inserted between the first side part (23) and the second side part (24), wherein the band spring (2) is configured to exert, with the spring thrust portion (9), the elastic prestress at least partially on the first central part (22) of the first convex portion (21), whereby the brake pad (5) is prestressed at least away from the brake disc (3) in the axial direction (AA), thereby preventing contact between the first side part (23) and the second side part (24) of the first convex portion (21). [2] Band spring and brake pad arrangement (1) according to the preceding claim, wherein the radially outer edge (20) comprises at least one second convex portion (25) forming a second concavity facing radially inward (RI), wherein the radially outer edge (20) comprises at least one concave portion (29) forming a third concavity facing radially outwards (RO), wherein the concave portion (29) is central to the first convex portion (21) and the second convex portion (25), wherein the spring thrust portion (9) exerts the elastic preload on the first convex portion (21) and on the second convex portion (25), whereby the brake pad (5) is preloaded at least away from the brake disc (3) in the axial direction (AA), thereby preventing contact with the concave portion (29). [3] Band spring and brake pad assembly (1) according to the preceding claim, comprising at least one of the following: wherein the second convex portion (25) has a second central part (26), a third side part (27) and a fourth side part (28), wherein the second central part (26) is inserted between the third side part (27) and the fourth side part (28), wherein the band spring (2) is designed to exert the elastic prestress at least partially on the second central part (26) of the second convex portion (25) with the spring thrust portion (9), whereby the brake pad (5) is biased at least away from the brake disc (4) in the axial direction (AA), while preventing contact between the third side part (27) and the fourth side part (28) of the second convex portion (25), and / or wherein the spring thrust portion (9) exerts the elastic preload on the first convex portion (21) and on the second convex portion (25), whereby the brake pad (5) is preloaded at least away from the brake disc (3) in the axial direction (AA) and the radial direction (RR), whereby only the first convex portion (21) and the second convex portion (25) are contacted, thereby preventing any other contact of the brake pad (5) with the spring thrust portion (9), and / or wherein the concave portion (29) is located radially inward relative to the first convex portion (21) and the second convex portion (25), wherein the concave portion (29) crosses the center line (AR). [4] Band spring and brake pad arrangement (1) according to the preceding claim, comprising one or more of the following features: wherein the spring thrust section (9) comprises a first spring edge (30) and a second spring edge (31) which are tangentially opposite to each other, wherein the spring thrust section (9) contacts the first convex section (21) with the first spring edge (30) and the second convex section (25) with the second spring edge (31), and / or wherein the spring thrust section (9) comprises a radially inner surface (32) which points radially inwards (RI) in the direction of the brake pad (5), wherein the radially inner surface (32) extends along the tangential direction (CC) between a first spring edge (33) and a second spring edge (34), wherein the spring thrust section (9) contacts the first convex section (21) with the first spring edge (33) and the second convex section (25) with the second spring edge (34) and / or wherein the spring thrust section (9) comprises a thrust end (35) which is adapted to contact the brake pad (5), wherein the thrust end (35) defines a thrust section width (36), wherein between the second side part (24) of the first convex portion (21) and the fourth side part (28) of the second convex portion (25) there is a first tangential distance along the tangential direction (CC) or a direction parallel thereto, wherein between the first side part (23) of the first convex portion (21) and the third side part (27) of the second convex portion (25) there is a second tangential distance along the tangential direction (CC) or a direction parallel to it, wherein the thrust section width (36) is greater than the first tangential distance and less than the second interference distance, so that the thrust end (35) interferes with the first central part (22) and with the second central section (27), thereby centering itself relative to the thrust section (12). [5] Band spring and brake pad arrangement (1) according to claim 1, wherein the first central part (22) is located radially outward relative to the first side part (23) and the second side part (24), wherein the first central part (22) is crossed by the centerline plane (AR), wherein the first central part (22) forms a radially outer apical portion of the radially outer edge (20), wherein the first central part (22) is the radially outermost portion of the radially outer edge (20), wherein the band spring (2) is adapted to exert the elastic prestress exclusively on the first central part (22) of the first convex portion (21) with the spring thrust portion (9), whereby the brake pad (5) is prestressed at least away from the brake disc (3) in the axial direction (AA). [6] Band spring and brake pad arrangement (1) according to the preceding claim or according to claim 1, comprising one or more of the following features: wherein the first convex portion (21) is a curved portion of the thrust portion (12) which forms a radially outer maximum of the thrust portion (12), and / or wherein the radially outer edge (20) comprises two concave portions (29) which are tangentially opposite relative to the at least one first convex portion (21), wherein the first convex portion (21) is located radially outward relative to the two concave portions (29), wherein the band spring (2) is adapted to exert the elastic prestress on the first convex portion (21) with the thrust portion (9), thereby preventing contact between the two concave portions (29). [7] Band spring and brake pad arrangement (1) according to one of the preceding claims, wherein the plate (10) comprises a free front surface (37) around the friction material (11), wherein the free front surface (37) faces the same side as the friction material (11), wherein the plate (10) comprises a rear side (38) which delimits the plate (10) on the side axially opposite the friction material (11), wherein the rear side (38) is adapted to face thrust elements (45) of the brake calliper (6), wherein the radially inner edge (19) is defined by the intersection point of the ramp (18) and the free front surface (37), wherein the thrust section (12) is delimited by an axial edge (39) which extends along the axial direction (AA) between the ramp (18) and the rear side (38), wherein the radially outer edge (20) is defined by the intersection point of the ramp (18) with the axial edge (39), wherein the spring thrust section (9) comprises a thrust end (35) which is adapted to contact the brake pad (5), wherein the thrust end (35) is bent by a spring angle (E) relative to the radial direction (RR) in the opposite direction relative to the brake pad (5), and wherein the ramp (18) is inclined by a ramp angle (F) relative to the radial direction (RR), wherein the ramp angle (F) is smaller than the spring angle (E) in order to prevent contact between the ramp (18) and the band spring (2). [8] Band spring and brake pad assembly (1) according to one of the preceding claims, wherein the plate (11) defines a spring housing (40) which is adapted to receive the spring thrust section (9), wherein the spring housing (40) passes through at least one plate thickness, wherein the plate (11) comprises a first lateral receiving wall (41) and a second lateral receiving wall (42) which are connected to the thrust section (12) and extend from the thrust section (12) at least in the radial direction (RR), whereby the spring housing (40) is tangentially delimited from opposite sides, wherein the spring housing (40) is limited radially inwardly (RI) by the thrust section (12) along the radial direction (RR), wherein the spring housing (40) is open radially outwards (RO) in the radial direction (RR) or is closed by a radially inner wall (43) which points radially inwards (RI), wherein the brake pad (5) passes through the spring housing (40) in order to arrange the thrust section (12) in the vicinity of a center of gravity of the friction material (10) or a thrust center of the brake pad (5). [9] Band spring and brake pad arrangement (1) according to one of the preceding claims, wherein the band spring (2) comprises a spring body (46), wherein the coupling section (8) comprises at least a first coupling arm (47) and a second coupling arm (48) which are adapted to engage the band spring (2) with the brake caliper body (6), wherein each coupling arm (47, 48) extends from a central spring section (50) to a respective coupling end (49), wherein the first coupling arm (47) and the second coupling arm (48) are bent substantially in a U-shape, wherein the band spring (2) comprises at least one first thrust arm (51) which extends from the central spring portion (50) to the spring thrust portion (9), wherein the spring thrust portion (9) has a respective thrust end (35). [10] Band spring and brake pad arrangement (1) according to the preceding claim, comprising one or more of the following features: wherein the strip spring (2) is obtained from a shaped and folded stamped sheet with a predetermined spring thickness, which forms a strip spring, wherein the coupling portion (8) is made in one piece with the spring thrust portion (9), e.g. wherein the engagement portion (8) is made as a tab in the spring body (46), wherein the coupling portion (8) and the spring thrust portion (9) are arranged in coincident or parallel folding planes, wherein the first coupling arm (47) and the second coupling arm (48) is adapted to engage around a tangential pull rod (63) which is parallel to the brake disc (3), or wherein the band spring (2) comprises a first spring band (57) and a second spring band (58) which are connected to one another at the central spring section (50), wherein the first spring band (57) forms the spring thrust section (9) and wherein the second spring band (58) forms the coupling section (8), and / or wherein the coupling portion (8) comprises a third coupling arm (59) and a fourth coupling arm (60), wherein the third coupling arm (59) cooperates with the first coupling arm (47) to retain the band spring (2) on a first axial pull rod (61) of the brake caliper body (6), which is arranged to span the brake disc (3), and wherein the fourth coupling arm (60) cooperates with the second coupling arm (48) to retain the band spring (2) on a second axial pull rod (62) of the brake caliper body (6), which is placed to span the brake disc (3), wherein the coupling portion (8) and the spring thrust portion (9) extend in mutually orthogonal directions. [11] Brake caliper (6) comprising a brake caliper body (7) adapted to span a brake disc (3), the brake caliper body (7) comprising a first elongate element (64), a second elongate element (65), a first connecting bridge (66) and a second connecting bridge (67) connecting the first elongate element (64) and the second elongate element (65) from tangentially opposite sides, at least one band spring and brake pad arrangement (1) according to one of the preceding claims, wherein the brake pad (5) is held by the brake calliper body (7) and is received in the brake calliper body (7), Thrust elements or pistons (45) which are accommodated in the first elongate element (64) and / or in the second elongate element (65) in order to preload at least the brake pad (5) in the direction of the brake disc (3). [12] Brake caliper (6) according to the preceding claim, comprising one or more of the following: - the brake caliper body (6) comprises a first axial tie rod (61) and the second axial tie rod (62) connecting the first elongate element (64) to the second elongate element (65) in the axial direction (AA), wherein the band spring (2) is engaged with the first axial tie rod (61) and the second axial tie rod (62), thereby preventing engagement with the first connecting bridge (66) and / or the second connecting bridge (67), or - the brake calliper body (6) comprises a tangential tie rod (63) which, suspended above the brake disc (3), connects the first connecting bridge (66) to the second connecting bridge (67) along the tangential direction (CC), the band spring (2) being engaged with the tangential tie rod (63); and / or wherein the first axial tension rod (61) and the second axial tension rod (62) have a tangential dimension of the axial tension rod or a tangential thickness (70) of the axial tension rod which is smaller than a thrust section width (36) of the thrust section (9), wherein the first axial tension rod (61) and the second axial tension rod (62) extend over the first elongate element (64) and the second elongate element (65), thereby forming reinforcing ribs (72) in reinforcing planes parallel to the axial direction (AA) and the radial direction (RR), and / or wherein the tangential pull rod (63) has an axial dimension of the tangential pull rod or an axial thickness (71) of the tangential pull rod which is smaller than a thrust section width (36) of the thrust section (9), and / or wherein the tangential distance between the first axial pull rod (61) and the second axial pull rod (62) is between three times and one and a half times the thrust section width (36) of the spring thrust section (9). [13] Brake pad (5) for a brake caliper (7), wherein the brake pad (5) defines an axial direction (AA), a radial direction (RR) perpendicular to the axial direction (AA) and a tangential direction (CC) perpendicular to both the axial direction (AA) and the radial direction (RR), comprising a plate (10) and a friction material (11) supported by the plate (10), wherein the friction material (11) is adapted to contact a braking surface (4) of a brake disc (3), wherein the brake disc (3) has an axis of rotation (XX) about which it rotates, wherein the axis of rotation (XX) is parallel to the axial direction (AA), wherein the plate (10) comprises a first tangential outer edge (14) and a second tangential outer edge (15) which are diametrically opposite or mirrored relative to a centerline plane (AR), wherein the centerline plane (AR) is parallel to the axial direction (AA) and radial direction (RR), wherein the plate (10) comprises a radially outer edge (16) and a radially inner edge (17), wherein the radially outer edge (16) points at least partially along the radial direction (RR) away from the axis of rotation (XX) radially outwards (RO), wherein the radially inner edge (16) points at least partially along the radial direction (RR) in the direction of the axis of rotation (XX) radially inwards (RI), wherein the radially outer edge (16) comprises a thrust portion (12) which is adapted to be contacted by a band spring (2) in order to absorb an elastic preload away from the brake disc (3), wherein the thrust section (12) is delimited by at least one ramp (18), wherein the ramp (18) is inclined at least relative to the axial direction (AA) and the radial direction (RR), wherein the ramp (18) points to the same side as the friction material (11), wherein the ramp (18) extends radially and axially away from the friction material (11) between a radially inner edge (19) and a radially outer edge (20), wherein the radially outer edge (20) extends crossing the center line plane (AR) at least in the radial direction (RR) and at least in the tangential direction (CC), wherein the radially outer edge (20) comprises at least one first convex portion (21), wherein the first convex portion (21) forms a first concavity which points radially inward (RI), wherein the first convex portion (21) comprises a first central part (22), a first side part (23) and a second side part (24), wherein the first central part (22) is inserted between the first side part (23) and the second side part (24), so that the band spring (2) is adapted to exert the elastic preload at least partially on the first central part (22) of the first convex portion (21), whereby the brake pad (5) is preloaded at least away from the brake disc (3) in the axial direction (AA) while contacting the first side part (23) and the second side part (24) of the first convex portion (21) is prevented.

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