Brake pad accessory and brake caliper

Abstract

A brake pad accessory according to an embodiment comprises, as an example: a base part configured to be removably attached to a backplate of a brake pad by an elastic force; a first spring extending from the base part and configured to push the brake pad in a direction away from a rotor; and an extension part extending from the base part. The extension part has at least one of: a wear alarm device configured to come into contact with the rotor when the distance between the backplate and the rotor is less than a prescribed distance; and a second spring configured to push the brake pad about a central axis of rotation of the rotor.

Description

Brake pad accessories and brake calipers

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to brake pad accessories and brake calipers.

[0002] A conventional disc brake includes a brake pad and a spring that separates the brake pad from the rotor when braking is released. The spring separates the brake pad from the rotor, thereby suppressing the generation of drag resistance (see Patent Document 1).

[0003] Japanese Patent Application Publication No. 5-272561

[0004] However, in the conventional configuration, the spring is fixed to the brake pad by crimping, so attaching the spring to the brake pad, i.e., providing the function of separating the brake pad from the rotor, is not an easy task.

[0005] Therefore, the present invention has been made in view of the above, and provides a brake pad accessory and a brake caliper to which a function for separating the brake pad from the rotor can be easily added.

[0006]

[0013] As one example, a brake pad accessory according to an embodiment of the present invention includes a base configured to be removably attached to a back plate of a brake pad by elastic force, a first spring extending from the base and configured to urge the brake pad in a direction away from a rotor, and an extension extending from the base, the extension having at least one of a wear warning device configured to contact the rotor when a distance between the back plate and the rotor is shorter than a predetermined distance, and a second spring configured to urge the brake pad around the central axis of rotation of the rotor. Thus, as one example, the accessory can be easily attached to the brake pad, and the function of separating the brake pad from the rotor can be easily added to a brake caliper.

[0007] FIG. 1 is a front view schematically showing a disc brake device according to a first embodiment. FIG. 2 is a top view showing a brake caliper according to the first embodiment. FIG. 3 is a front view showing the brake caliper according to the first embodiment. FIG. 4 is a top view showing a pad assembly according to the first embodiment. FIG. 5 is a cross-sectional view partially showing a pad assembly, mounting, and pad support according to the first embodiment. FIG. 6 is a cross-sectional view showing a disc rotor, pad assembly, mounting, and pad support according to the first embodiment along line F6-F6 in FIG. 5. FIG. 7 is a perspective view showing an accessory according to the first embodiment. FIG. 8 is a perspective view showing a portion of the pad assembly according to the first embodiment. FIG. 9 is a perspective view showing a portion of the brake caliper according to the first embodiment. FIG. 10 is a perspective view showing an accessory according to a second embodiment. FIG. 11 is a cross-sectional view showing a disc rotor, pad assembly, mounting, and pad support according to the second embodiment.

[0008] (First embodiment) A first embodiment will be described below with reference to FIGS. 1 to 9. Note that in this specification, components according to the embodiment and descriptions of the components may be described using multiple expressions. The components and their descriptions are merely examples and are not limited by the expressions in this specification. The components may also be identified by names different from those in this specification. Furthermore, the components may also be described using expressions different from those in this specification.

[0009] In the following description, "suppress" is defined as, for example, preventing an event, action, or influence from occurring, or reducing the severity of an event, action, or influence. Also, in the following description, "restrict" is defined as, for example, preventing movement or rotation, or allowing movement or rotation within a predetermined range and preventing movement or rotation beyond the predetermined range.

[0010] Fig. 1 is a front view that schematically shows a disc brake device 10 according to a first embodiment. The disc brake device 10 is mounted on a vehicle 1 such as a four-wheeled automobile. However, the disc brake device 10 is not limited to this example. As shown in Fig. 1, the disc brake device 10 has a disc rotor 11 and a brake caliper 12. The disc rotor 11 is an example of a rotor.

[0011] The disc rotor 11 rotates about a central axis Ax integrally with the wheel of the vehicle 1. The central axis Ax is, for example, the central axis of an axle, the central axis of the disc rotor 11, and also the central axis of rotation of the disc rotor 11. Note that the central axis Ax is not limited to this example.

[0012] Hereinafter, for convenience, the axial direction, radial direction, and circumferential direction are defined. The axial direction is the direction along the central axis Ax. The radial direction is the direction perpendicular to the central axis Ax. The circumferential direction is the direction around the central axis Ax.

[0013] The circumferential direction includes a forward rotation direction Dcn and a reverse rotation direction Dcr shown in FIG. 1 . The forward rotation direction Dcn is one direction around the central axis Ax. The reverse rotation direction Dcr is the opposite direction around the central axis Ax. When the vehicle 1 moves forward, the disc rotor 11 rotates in the forward rotation direction Dcn. On the other hand, when the vehicle 1 moves backward, the disc rotor 11 rotates in the reverse rotation direction Dcr.

[0014] The disc rotor 11 includes a rotor body 11 a and a hat portion 11 b. The rotor body 11 a is formed in a disk shape that is substantially perpendicular to the central axis Ax. The hat portion 11 b is formed in a substantially cylindrical shape and is coupled to, for example, an axle of the vehicle 1.

[0015] 2 is a top view showing the brake caliper 12 of the first embodiment. As shown in FIG. 2, the brake caliper 12 of this embodiment is a floating caliper. However, the brake caliper may be another type of caliper, such as an opposed caliper. The brake caliper 12 is disposed so as to straddle the rotor body 11a.

[0016] 2 and 3, the brake caliper 12 has a pair of brake pad assemblies (hereinafter referred to as pad assemblies) 21, a mounting 22, a movable caliper 23, and two pairs of pad support springs (hereinafter referred to as pad supports) 24. The mounting 22 is an example of a caliper body.

[0017] 4 is a top view showing the pad assembly 21 of the first embodiment. The pair of pad assemblies 21 are arranged axially and mirror-symmetrically. The rotor body 11a is arranged between the pair of pad assemblies 21.

[0018] Each of the pair of pad assemblies 21 includes a brake pad 25 and an accessory 26. The accessory 26 is an example of an accessory of a brake pad, and may also be referred to as, for example, a pad mounting member, a spring component, a compression spring, or a pad wear indicator (PWI).

[0019] In this embodiment, the pair of brake pads 25 are formed to have substantially the same shape. However, the pair of brake pads 25 may have different shapes. Each of the pair of brake pads 25 has a back plate 31, a friction material 32, and a shim 33.

[0020] 5 is a cross-sectional view partially illustrating the pad assembly 21, mounting 22, and pad support 24 of the first embodiment. The back plate 31 is disposed substantially perpendicular to the central axis Ax and is formed in a plate shape extending substantially in the circumferential direction. The back plate 31 has two end portions 31a in the circumferential direction. FIG. 5 illustrates the end portion 31a of the two end portions 31a in the reverse direction Dcr.

[0021] As shown in Figure 4, the back plate 31 further has a mounting surface 31b and a back surface 31c that face substantially in the axial direction. The mounting surface 31b is an example of a second surface. The back surface 31c is an example of a first surface. The mounting surface 31b faces the rotor body 11a. The back surface 31c is located on the opposite side of the mounting surface 31b.

[0022] 5, a pair of protrusions 35 are provided on the back plate 31. The protrusions 35 are provided on an end portion 31a of the back plate 31. The protrusions 35 are formed integrally with the back plate 31.

[0023] Each of the pair of protrusions 35 has an inner surface 35 a, an outer surface 35 b, and an end surface 35 c. The inner surface 35 a faces radially inward. The outer surface 35 b is located opposite the inner surface 35 a and faces radially outward. The end surface 35 c is provided between the end of the inner surface 35 a and the end of the outer surface 35 b and faces the circumferential direction as a whole.

[0024] The end surface 35c of this embodiment has an uneven surface. Specifically, the end surface 35c includes an inner end surface 35d, an inner locking surface 35e, a bottom surface 35f, an outer locking surface 35g, and an outer end surface 35h. The inner end surface 35d may also be referred to as a torque transmission surface.

[0025] The inner end surface 35 d, the bottom surface 35 f, and the outer end surface 35 h extend in a substantially radial direction. For example, the inner end surface 35 d, the bottom surface 35 f, and the outer end surface 35 h extend substantially parallel to an imaginary line that passes through the center of the back plate 31 in the circumferential direction and extends in the radial direction.

[0026] The inner end surface 35d extends radially outward from the circumferential end of the inner surface 35a and is located at the circumferential end of the protrusion 35. The inner locking surface 35e extends radially outward from the radially outer end of the inner end surface 35d toward the circumferential center of the back plate 31.

[0027] The bottom surface 35f extends radially outward from the circumferential end of the inner locking surface 35e. The outer locking surface 35g extends substantially circumferentially from the radially outer end of the bottom surface 35f and faces radially inward. The outer end surface 35h extends between the circumferential end of the outer side surface 35b and the circumferential end of the outer locking surface 35g.

[0028] The outer end surface 35h is closer to the center of the back plate 31 than the inner end surface 35d. The bottom surface 35f is closer to the center of the back plate 31 than the outer end surface 35h. Therefore, the inner locking surface 35e, the bottom surface 35f, and the outer locking surface 35g form a recess 36 recessed from the inner end surface 35d and the outer end surface 35h.

[0029] Figure 6 is a cross-sectional view showing the disc rotor 11, pad assembly 21, mounting 22, and pad support 24 of the first embodiment, taken along line F6-F6 in Figure 5. As shown in Figure 6, a recess 37 is provided in the protrusion 35. The recess 37 is recessed in the axial direction from the mounting surface 31b of the back plate 31 in the protrusion 35. The recess 37 is spaced apart from the inner surface 35a and the outer surface 35b in the radial direction.

[0030] 4, the friction material 32 is fixed to the mounting surface 31b of the back plate 31. The friction material 32 is located between the mounting surface 31b and the rotor body 11a. The shim 33 is attached to the back surface 31c of the back plate 31.

[0031] The accessory 26 is attached to one of the protrusions 35 of the brake pad 25. In this embodiment, the accessory 26 is attached to the protrusion 35 provided on the end 31 a in the reverse rotation direction Dcr. Note that the accessory 26 may be attached to the protrusion 35 provided on the end 31 a in the forward rotation direction Dcn, or two accessories 26 may be attached to two protrusions 35.

[0032] The mounting 22 is fixed to a non-rotating portion of the vehicle 1. For example, the mounting 22 is attached to the body of the vehicle 1. The mounting 22 supports the pad assembly 21, the movable caliper 23, and the pad support 24.

[0033] As shown in Figure 2, the mounting 22 has two pairs of support parts 41. One pair of support parts 41 and the other pair of support parts 41 are aligned in the axial direction. Each pair of support parts 41 supports a pair of protrusions 35 of the corresponding brake pad 25 so that the brake pad 25 can move in the axial direction. The rotor body 11a is disposed between the pair of support parts 41 and the other pair of support parts 41. A corresponding pad support 24 is attached to each of the two pairs of support parts 41.

[0034] 6, each of the plurality of support portions 41 has two side surfaces 41a and 41b. The side surface 41a faces the rotor body 11a. The side surface 41b is located on the opposite side to the side surface 41a.

[0035] As shown in Fig. 5, each of the support portions 41 further has a concave surface 41c. The concave surface 41c extends in the axial direction between the two side surfaces 41a, 41b. The concave surface 41c forms (defines, defines) a recess 45. That is, the recess 45 is provided in each of the support portions 41. The recess 45 extends in the axial direction. The axial lengths of the concave surface 41c and the recess 45 are each longer than the axial length (thickness) of the back plate 31.

[0036] The concave surface 41c has an inner surface 45a, an outer surface 45b, and an end surface 45c. The end surface 45c may also be referred to as a torque transmission surface. The inner surface 45a faces radially outward. The outer surface 45b faces radially inward. The inner surface 45a and the outer surface 45b face each other. The end surface 45c is located between the end of the inner surface 45a and the end of the outer surface 45b and faces in the circumferential direction.

[0037] The protrusion 35 is fitted (housed) in the recess 45. The inner surface 45a faces the inner surface 35a of the protrusion 35 via a gap. The outer surface 45b faces the outer surface 35b of the protrusion 35 via a gap. The end surface 45c faces the end surface 35c of the protrusion 35 via a gap.

[0038] 2, the movable caliper 23 includes a pressing device 23a. The pressing device 23a includes, for example, a cylinder, a piston, and an actuator that drives the piston. The pressing device 23a is disposed inward of the disc rotor 11 in the vehicle width direction.

[0039] The pressing device 23a is hydraulically or electrically operated, and uses a piston to axially press one of the pair of brake pads 25, which is an inner brake pad. As a result, the friction material 32 of the inner brake pad 25 is pressed against the rotor body 11a.

[0040] When the inner brake pad 25 is pressed against the rotor body 11 a, the movable caliper 23 moves in a direction opposite to the moving direction of the piston due to reaction, thereby pressing one of the outer brake pads 25 against the rotor body 11 a.

[0041] Specifically, the movable caliper 23 presses the back plate 31 via the shim 33. This causes the friction material 32 to come into contact with the rotor body 11a. Note that the shim 33 may be omitted, and the movable caliper 23 may press the back plate 31 directly.

[0042] As shown in Figure 5, two pairs of pad supports 24 are attached to the mounting 22. Each of the multiple pad supports 24 is fitted into a corresponding recess 45. The pad supports 24 are interposed between the brake pads 25 and the mounting 22 and hold the brake pads 25 axially movable. In other words, the mounting 22 supports the brake pads 25 via the pad supports 24 so that they are axially movable relative to the disc rotor 11.

[0043] The pad support 24 is formed, for example, from a bent metal plate and has elasticity. The pad support 24 has an inner plate portion 51, an outer plate portion 52, a connecting plate portion 53, and a pad holding portion 54. The connecting plate portion 53 may also be referred to as a torque transmission portion. Furthermore, as shown in FIG. 6 , the pad support 24 further has two holding plate portions 56 and 57.

[0044] The inner plate 51, the outer plate 52, the connecting plate 53, and the two retaining plates 56, 57 are formed in a plate shape. As shown in Figure 5, the inner plate 51, the outer plate 52, and the connecting plate 53 are formed in a generally U-shape as a whole and are interposed between the protrusion 35 and the recessed surface 41c. The protrusion 35 is supported by the mounting 22 via the pad support 24.

[0045] The inner plate portion 51 is located between the inner surface 35 a of the protrusion 35 and the inner surface 45 a of the mounting 22, and extends in a substantially circumferential direction. The outer plate portion 52 is located between the outer surface 35 b of the protrusion 35 and the outer surface 45 b of the mounting 22, and extends in a substantially circumferential direction.

[0046] The connecting plate portion 53 is provided between one circumferential end of the inner plate portion 51 and one circumferential end of the outer plate portion 52. The connecting plate portion 53 is located between the end face 35c of the protrusion 35 and the end face 45c of the mounting 22, and extends in a substantially radial direction. The connecting plate portion 53 contacts the end face 45c of the mounting 22.

[0047] The pad holding portion 54 is, for example, a leaf spring extending from an axial end of the inner plate portion 51. A portion of the pad holding portion 54 is located between the inner plate portion 51 and the protrusion 35 and contacts the inner surface 35a of the protrusion 35. The pad holding portion 54 presses the protrusion 35 against the outer plate portion 52 to hold the brake pad 25 in the radial direction.

[0048] The brake pad 25 can move within a predetermined range in the circumferential direction relative to the mounting 22 and the pad support 24. When the brake pad 25 moves to its maximum extent in one circumferential direction, the inner end surface 35d of the protrusion 35 comes into contact with the connecting plate portion 53 of the pad support 24. Note that other portions of the back plate 31 may also come into contact with the pad support 24. When the brake pad 25 moves in the other circumferential direction, the inner end surface 35d moves away from the connecting plate portion 53.

[0049] As shown in Figure 6, the holding plate 56 extends from one axial end of the connecting plate 53. The holding plate 56 abuts against the side surface 41a of the support portion 41. The holding plate 57 extends from the other axial end of the connecting plate 53. The holding plate 57 abuts against the side surface 41b of the support portion 41. The pad support 24 holds the support portion 41 between the two holding plates 56, 57 by elastic force.

[0050] Fig. 7 is a perspective view showing the accessory 26 of the first embodiment. As shown in Fig. 7, the accessory 26 is formed, for example, from a bent metal plate and has elasticity. The accessory 26 has a base 61, a return spring 62, and an extension 63. The return spring 62 is an example of a first spring. The base 61, the return spring 62, and the extension 63 are formed in a plate shape.

[0051] 6, the base 61 is formed in a generally U-shape and includes two holding plates 71 and 72 and a connecting portion 73. The holding plate 71 is an example of a second wall. The holding plate 72 is an example of a first wall.

[0052] The holding plate 71 is disposed along the mounting surface 31b of the back plate 31. The holding plate 72 is disposed along the back surface 31c of the back plate 31. The connecting portion 73 extends substantially in the axial direction between one end 71a of the holding plate 71 in the circumferential direction and one end 72a of the holding plate 72 in the circumferential direction. The connecting portion 73 connects the two holding plates 71, 72.

[0053] Fig. 8 is a perspective view showing a portion of the pad assembly 21 of the first embodiment. As shown in Fig. 8, the connecting portion 73 is at least partially housed in the recess 36. Therefore, as shown in Fig. 5, the connecting portion 73 is disposed along the bottom surface 35f of the back plate 31 and is located between the inner locking surface 35e and the outer locking surface 35g.

[0054] 6, a protrusion 75 is provided on the other circumferential end 71b of the holding plate 71. The protrusion 75 protrudes from the holding plate 71 toward the mounting surface 31b of the back plate 31.

[0055] When the accessory 26 is detached from the brake pad 25, the minimum distance between the protrusion 75 and the retaining plate portion 72 is greater than the thickness of the back plate 31. Furthermore, the minimum distance between the protrusion 75 and the retaining plate portion 72 is, for example, the distance between the recess 37 and the back surface 31c.

[0056] The holding plate 72 contacts the rear surface 31c of the back plate 31. Furthermore, the protrusion 75 is fitted into the recess 37 and contacts the bottom surface of the recess 37. The protrusion 35 of the back plate 31 is located between the two holding plates 71, 72 so as to widen the gap between the protrusion 75 and the holding plate 72. Therefore, the protrusion 35 elastically deforms the base 61.

[0057] The base 61 holds the protrusion 35 of the back plate 31 between the two holding plate portions 71, 72 by elastic force, so that the base 61 is removably attached to the back plate 31 by elastic force.

[0058] The retaining plates 71, 72 restrict axial movement of the base 61 relative to the back plate 31. The connecting portion 73 and the protrusion 75 fitted in the recess 37 restrict circumferential movement of the base 61 relative to the back plate 31. Furthermore, the protrusion 75 fitted in the recess 37, the inner locking surface 35e, and the outer locking surface 35g restrict radial movement of the base 61 relative to the back plate 31.

[0059] The return spring 62 and the extension 63 extend from the other circumferential end 72b of the retaining plate 72 in a direction away from the rotor body 11a. The end 72b is an example of an edge of the first wall. Note that the direction away from the rotor body 11a is not limited to a direction perpendicular to the rotor body 11a.

[0060] 7, the return spring 62 of this embodiment is formed in a substantially Y-shape or a substantially V-shape. However, the return spring 62 may have other shapes. The return spring 62 has a first arm 81, a second arm 82, and a pressing portion 83.

[0061] The first arm 81 and the second arm 82 extend substantially parallel to each other. Each of the first arm 81 and the second arm 82 has a straight portion 85 and a curved portion 86. The straight portion 85 extends from the end portion 72b of the retaining plate portion 72 in a direction away from the rotor body 11a. That is, each of the first arm 81 and the second arm 82 extends from the base portion 61. The curved portion 86 extends in an arc shape from the straight portion 85. Note that the first arm 81 and the second arm 82 are not limited to this example.

[0062] The pressing portion 83 is connected to the curved portions 86 of the first arm 81 and the second arm 82. In other words, the pressing portion 83 connects the first arm 81 and the second arm 82 at a position spaced apart from the base 61. As shown in Fig. 6 , the pressing portion 83 is spaced apart in the circumferential direction from the back plate 31 and the base 61. Furthermore, the pressing portion 83 is spaced apart from the rotor body 11a more than the base 61 is.

[0063] 9 is a perspective view showing a portion of the brake caliper 12 of the first embodiment. As shown in Fig. 9, the pressing portion 83 contacts the side surface 41b of the support portion 41 of the mounting 22 at a position radially spaced from the holding plate portion 57 of the pad support 24. Note that the pressing portion 83 may also contact another component such as the pad support 24.

[0064] 7 , the extension portion 63 extends from the base portion 61 between the first arm 81 and the second arm 82. The extension portion 63 has a compression spring 91 and a PWI 92. The compression spring 91 is an example of a second spring. Note that the extension portion 63 may have only one of the compression spring 91 and the PWI 92.

[0065] The compression spring 91 has a curved portion 94, a straight portion 95, and a protrusion 96. The curved portion 94 extends in an arc shape from the end portion 72b of the holding plate portion 72. The straight portion 95 extends from the curved portion 94 in a substantially axial direction. In other words, the curved portion 94 is provided between the base portion 61 and the straight portion 95.

[0066] 6 , the straight portion 95 is located between the back plate 31 and the connecting plate portion 53 of the pad support 24. Furthermore, the straight portion 95 is located between the base portion 61 and the connecting plate portion 53. The straight portion 95 is spaced apart from the base portion 61.

[0067] The protrusion 96 protrudes from the straight portion 95 toward the connecting plate portion 53. The protrusion 96 is formed, for example, in a substantially hemispherical shape. However, the protrusion 96 is not limited to this example. The protrusion 96 makes substantially point contact or line contact with the connecting plate portion 53. However, the protrusion 96 may also make contact with the end surface 45 c of the support portion 41 of the mounting 22.

[0068] The curved portion 94 is elastically deformed so that the base portion 61 and the straight portion 95 approach each other. As a result, the compression spring 91 presses the connecting plate portion 53 in the reverse direction Dcr by its elastic force. Furthermore, the compression spring 91 presses the brake pad 25 attached to the base portion 61 in the forward rotation direction Dcn (circumferential direction) by its elastic force (reaction force). As a result, the inner end surface 35d of the convex portion 35 at the end portion 31a in the forward rotation direction Dcn is pressed against the connecting plate portion 53 of the pad support 24. In other words, the compression spring 91 holds the brake pad 25 in the circumferential direction by its elastic force.

[0069] The PWI 92 extends from the straight portion 95 of the compression spring 91 toward the rotor body 11a. The end portion 92a of the PWI 92 closest to the rotor body 11a is closer to the rotor body 11a than the base portion 61. Therefore, the end portion 92a of the PWI 92 is closer to the rotor body 11a than the back plate 31.

[0070] When the disc brake device 10 brakes the disc rotor 11 and the wheel, the pressing device 23a moves the brake pad 25 in the axial direction toward the rotor body 11a. The brake pad 25 moves in the axial direction along the recess 45, and the friction material 32 comes into contact with the rotor body 11a.

[0071] As the brake pads 25 approach the rotor body 11a, the base 61 attached to the back plate 31 also moves toward the rotor body 11a. On the other hand, the mounting 22 is attached to a non-rotating portion of the vehicle 1 and therefore does not move relative to the vehicle 1. The pressing portion 83 of the return spring 62 also abuts against the side surface 41b of the mounting 22 and therefore remains in approximately the same position. In other words, the distance between the base 61 and the pressing portion 83 in the axial direction increases.

[0072] When the distance between the base 61 and the pressing portion 83 increases, for example, the curved portion 86 of the return spring 62 elastically deforms. As a result, the pressing portion 83 of the return spring 62 presses the side surface 41 b of the mounting 22 toward the rotor body 11 a by its elastic force. Furthermore, the return spring 62 presses the brake pad 25 attached to the base 61 in a direction away from the rotor body 11 a by the reaction force (elastic force) that presses the mounting 22.

[0073] The force with which the return spring 62 presses the brake pad 25 is smaller than the force with which the pressing device 23a presses the brake pad 25. Therefore, the pressing device 23a moves the brake pad 25 toward the rotor body 11a against the force with which the return spring 62 presses the brake pad 25.

[0074] When the friction material 32 comes into contact with the disc rotor 11 rotating in the forward rotation direction Dcn, the brake pad 25 receives a force in the forward rotation direction Dcn due to friction between the rotor body 11a and the friction material 32. As a result, at the end 31a in the forward rotation direction Dcn, the inner end surface 35d of the protrusion 35 presses the end surface 45c of the mounting 22 via the corresponding connecting plate portion 53 of the pad support 24.

[0075] The mounting 22 receives the braking force (braking torque) transmitted via the brake pads 25 and transmits it to the body of the vehicle 1. In this way, the disc brake device 10 brakes the disc rotor 11.

[0076] When the brake is released and the pressure is released, the return spring 62 separates the brake pad 25 from the rotor body 11a by its elastic force, against the friction (sliding resistance) between the protrusion 35 and the pad support 24, for example. As a result, the friction material 32 is quickly separated from the rotor body 11a, and it is possible to suppress the generation of drag resistance (drag torque) between the friction material 32 and the rotor body 11a.

[0077] As the friction material 32 wears, the distance between the back plate 31 and the rotor body 11 a when the friction material 32 contacts the rotor body 11 a decreases, and therefore the distance between the end 92 a of the PWI 92 and the rotor body 11 a also decreases.

[0078] When the friction material 32 wears beyond a predetermined amount, the distance between the back plate 31 and the rotor body 11a becomes shorter than a predetermined limit (distance) when the friction material 32 contacts the rotor body 11a. At this time, the end 92a of the PWI 92 contacts the rotor body 11a.

[0079] When the PWI 92 comes into contact with the rotating rotor body 11a, an alarm (chatter noise) is generated. The alarm alerts the driver that the friction material 32 has worn beyond a predetermined amount. The PWI 92 can generate the alarm before the back plate 31 and the base 61 come into contact with the rotor body 11a.

[0080] The accessory 26 can be easily attached to the back plate 31 by holding the back plate 31 between the holding plate portions 71 and 72 of the base 61. In other words, attaching the accessory 26 to the back plate 31 does not require work using dedicated equipment or tools such as crimping or screw fastening.

[0081] For example, there may be a case where a conventional accessory that does not have a return spring 62 is attached to the back plate 31 of an existing vehicle 1. The accessory 26 can be attached to the back plate 31 in place of the conventional accessory, thereby adding the return spring 62 to the pad assembly 21. The replacement of the conventional accessory with the accessory 26 can be easily performed even at a service center such as a vehicle dealership that does not have any processing facilities or tools.

[0082] The back plate 31 is provided with recesses 37 into which the protrusions 75 of the accessory 26 are fitted. However, since the recesses 37 are provided on the mounting surface 31b, they can be provided at the same time as forming the back plate 31 by press working, for example. Therefore, the accessory 26 can be attached to the existing back plate 31 without any additional work such as drilling.

[0083] In the brake caliper 12 according to the first embodiment described above, the accessory 26 has a base 61, a return spring 62, and an extension 63. The base 61 is removably attached to the back plate 31 of the brake pad 25 by elastic force. The return spring 62 extends from the base 61 and is configured to push the brake pad 25 in a direction away from the disc rotor 11. The extension 63 extends from the base 61 and has at least one of a PWI 92 and a compression spring 91. The PWI 92 is configured to contact the disc rotor 11 when the distance between the back plate 31 and the disc rotor 11 is shorter than a predetermined distance. The compression spring 91 is configured to push the brake pad 25 around the central axis Ax.

[0084] The return spring 62 separates the brake pad 25 from the disc rotor 11, thereby suppressing drag resistance that would otherwise occur due to contact between the brake pad 25 and the disc rotor 11 when braking is released. As a result, the accessory 26 can suppress noise generation and reduced fuel economy. Conventionally, an accessory having at least one of a PWI and a compression spring has been attached to the brake pad 25. On the other hand, the accessory 26 of this embodiment further includes a return spring 62 in addition to at least one of a PWI 92 and a compression spring 91, and is removably attached to the back plate 31 at the base 61. This allows the accessory 26 to be attached to the brake pad 25 in place of a conventional accessory, thereby easily adding a function for separating the brake pad 25 from the disc rotor 11 to the brake caliper 12. Furthermore, the accessory 26 can be easily attached to the back plate 31 by elastic force. Therefore, the accessory 26 can be detached from the brake pad 25 before assembling the brake caliper 12, thereby suppressing inconvenience in handling that would otherwise be caused by the accessory being attached to the brake pad 25. Furthermore, the attachment 26 can be easily attached to the brake pad 25 without the need for equipment for processing such as caulking.

[0085] The base 61 has a holding plate portion 72, a holding plate portion 71, and a connecting portion 73. The holding plate portion 72 is arranged along the back surface 31c of the back plate 31. The holding plate portion 71 is arranged along the mounting surface 31b of the back plate 31 located on the opposite side of the back surface 31c. The connecting portion 73 connects the holding plate portion 72 and the holding plate portion 71. The base 61 is configured to hold the back plate 31 between the holding plate portion 72 and the holding plate portion 71 by elastic force. The return spring 62 and the extension portion 63 extend from the end portion 72b of the holding plate portion 72. This allows the accessory 26 to be made, for example, from a single bent plate material.

[0086] The return spring 62 has a first arm 81, a second arm 82, and a pressing portion 83. The first arm 81 and the second arm 82 each extend from the base 61. The pressing portion 83 connects the first arm 81 and the second arm 82 at a position spaced apart from the base 61 and is configured to press the mounting 22. The extension portion 63 extends from the base 61 between the first arm 81 and the second arm 82. This allows the accessory 26 attached to the inner brake pad 25 and the accessory 26 attached to the outer brake pad 25 to have a common shape. This reduces the cost of the accessory 26 and allows the forces acting on the inner brake pad 25 and the outer brake pad 25 to be approximately equal. Furthermore, the accessory 26 allows the reaction force of the return spring 62 to be applied approximately evenly to both sides of the extension portion 63. Therefore, the accessory 26 can prevent the brake pad 25 from tilting (rotating) about the axis (for example, an axis extending in the circumferential direction) of the position (protrusion 96) where the compression spring 91 presses the mounting 22, thereby stabilizing the attitude of the brake pad 25. By stabilizing the attitude of the brake pad 25, the PWI 92 can more accurately contact the disc rotor 11 when the distance between the back plate 31 and the disc rotor 11 becomes shorter than a predetermined distance, improving the detection accuracy of the PWI 92.

[0087] The brake caliper 12 has brake pads 25, accessories 26 attached to the brake pads 25, and a mounting 22 that supports the brake pads 25 movably in a direction along the central axis Ax. The return springs 62 are configured to push the brake pads 25 in a direction away from the disc rotor 11 by using a reaction force that pushes the mounting 22. As described above, the return springs 62 move the brake pads 25 away from the disc rotor 11, thereby suppressing the generation of drag resistance caused by contact between the brake pads 25 and the disc rotor 11 when braking is released. This allows the brake caliper 12 to suppress the generation of noise and a decrease in fuel efficiency.

[0088] The return spring 62 and the extension 63 extend from the base 61 in a direction away from the disc rotor 11. This prevents the return spring 62 and the extension 63 from interfering with the disc rotor 11 even if the friction material 32 of the brake pad 25 is worn.

[0089] Second Embodiment A second embodiment will be described below with reference to Figures 10 and 11. In the following description of the embodiment, components having the same functions as components already described are given the same reference numerals as the components already described, and further description may be omitted. Furthermore, multiple components given the same reference numerals do not necessarily have all the same functions and properties, and may have different functions and properties according to each embodiment.

[0090] Fig. 10 is a perspective view showing an accessory 26 according to the second embodiment. Fig. 11 is a cross-sectional view showing the disc rotor 11, pad assembly 21, mounting 22, and pad support 24 according to the second embodiment.

[0091] 10, the second embodiment of accessory 26 has a return spring 201 and an extension 202 instead of return spring 62 and extension 63. Return spring 201 and extension 202 are substantially identical to return spring 62 and extension 63, except as described below.

[0092] The return spring 201 has a first arm 211, a second arm 212, and a pressing portion 213. The first arm 211 and the second arm 212 extend substantially parallel to each other. Each of the first arm 211 and the second arm 212 has a first curved portion 215, a first straight portion 216, a second curved portion 217, and a second straight portion 218.

[0093] The first curved portion 215 extends in an arc shape from the end portion 72b of the retaining plate portion 72 in a direction away from the rotor body 11a. The first straight portion 216 extends from the first curved portion 215 in a direction away from the rotor body 11a. The second curved portion 217 extends in an arc shape from the first straight portion 216. The second straight portion 218 extends from the second curved portion 217 toward the side surface 41b of the support portion 41 of the mounting 22. Note that the first arm 211 and the second arm 212 are not limited to this example.

[0094] The radius of the first curved portion 215 is larger than the radius of the second curved portion 217. The lengths of the first straight portion 216 and the second straight portion 218 are each larger than the radius of the second curved portion 217. Note that the first arm 211 and the second arm 212 are not limited to this example.

[0095] The pressing portion 213 connects the second straight portions 218 of the first arm 211 and the second arm 212 to each other at a position spaced apart from the base 61. As shown in FIG. 11 , the pressing portion 213 comes into contact with the side surface 41 b of the support portion 41 of the mounting 22.

[0096] When the distance between the base 61 and the pressing portion 213 increases due to movement of the brake pad 25, for example, the first bent portion 215 or the second bent portion 217 of the return spring 201 elastically deforms. As a result, the pressing portion 213 of the return spring 201 presses the side surface 41 b of the mounting 22 toward the rotor body 11 a by its elastic force. Furthermore, the return spring 201 presses the brake pad 25 attached to the base 61 in a direction away from the rotor body 11 a by the reaction force (elastic force) that presses the mounting 22.

[0097] The extension portion 202 extends from the base portion 61 between the first arm 211 and the second arm 212. The extension portion 202 has a compression spring 221 and a PWI 222. Note that the extension portion 202 may have only one of the compression spring 221 and the PWI 222.

[0098] The compression spring 221 has a curved portion 225 and a protrusion 226. The curved portion 225 extends in a roughly arc shape from the end portion 72b of the holding plate portion 72. A portion of the curved portion 225 is located between the back plate 31 and the connecting plate portion 53, and also between the base portion 61 and the connecting plate portion 53. The curved portion 225 is spaced apart from the base portion 61 between the back plate 31 and the connecting plate portion 53.

[0099] The protrusion 226 protrudes from the curved portion 225 toward the connecting plate portion 53. The protrusion 226 extends, for example, in a substantially arc shape along the curved portion 225. The protrusion 226 makes substantially point contact or line contact with the connecting plate portion 53.

[0100] The curved portion 225 is elastically deformed so as to approach the base portion 61. As a result, the compression spring 221 uses its elastic force to push the connecting plate portion 53 in the reverse rotation direction Dcr. Furthermore, the compression spring 221 uses its elastic force (reaction force) to push the brake pad 25 in the forward rotation direction Dcn.

[0101] The PWI 222 extends toward the rotor body 11a from the curved portion 225 of the compression spring 221. When the distance between the back plate 31 and the rotor body 11a is shorter than a predetermined distance, the PWI 222 comes into contact with the rotor body 11a.

[0102] As described above, the accessory 26 may have various shapes. The shapes of the return springs 62, 201 and the extensions 63, 202 may be set depending on, for example, the desired elastic force and the arrangement of various components in the brake caliper 12.

[0103] The brake pad accessory according to at least one embodiment described above includes, for example, a base configured to be removably attached to a back plate of a brake pad by elastic force, a first spring extending from the base and configured to push the brake pad in a direction away from a rotor, and an extension extending from the base. The extension includes at least one of a wear warning device configured to contact the rotor when the distance between the back plate and the rotor is shorter than a predetermined distance, and a second spring configured to push the brake pad around the central axis of rotation of the rotor. Thus, for example, the first spring separates the brake pad from the rotor, thereby suppressing the generation of drag resistance caused by contact between the brake pad and the rotor when braking is released. This allows the brake pad accessory to suppress noise generation and reduced fuel economy. Conventionally, an accessory including at least one of a wear warning device and a circumferential compression spring (second spring) has been attached to a brake pad. On the other hand, the accessory of the embodiment further includes a first spring in addition to at least one of the wear warning device and the second spring, and is removably attached to the back plate at the base. This allows the accessory of the embodiment to be attached to the brake pad in place of a conventional accessory, and the function of separating the brake pad from the rotor can be easily added to the brake caliper. Furthermore, the accessory of the embodiment can be easily attached to the back plate by elastic force. Therefore, the accessory of the embodiment can be detached from the brake pad before assembling the brake caliper, thereby reducing the inconvenience of handling, for example, caused by the accessory being attached to the brake pad. Furthermore, the accessory of the embodiment can be easily attached to the brake pad without equipment for processing such as crimping.

[0104] In the brake pad accessory, as one example, the base has a first wall arranged along a first surface of the back plate, a second wall arranged along a second surface of the back plate opposite the first surface, and a connecting portion connecting the first wall and the second wall, and is configured to hold the back plate between the first wall and the second wall by the elastic force, and the first spring and the extension portion extend from an edge of the first wall. Thus, as one example, the accessory of the embodiment can be made of, for example, a single bent plate material.

[0105] In the brake pad accessory, for example, the first spring has a first arm extending from the base, a second arm extending from the base, and a pressing portion connecting the first arm and the second arm at a position spaced from the base and configured to press against the caliper body, and the extension portion extends from the base between the first arm and the second arm. Therefore, for example, the accessory attached to the inner brake pad and the accessory attached to the outer brake pad can have a common shape. This reduces the cost of the accessory and allows the forces acting on the inner brake pad and the outer brake pad to be approximately equal. Furthermore, the accessory of this embodiment can apply the reaction force of the first spring approximately evenly to both sides of the extension portion. Therefore, the accessory can prevent the brake pad from tilting and stabilize the posture of the brake pad. By stabilizing the posture of the brake pad, the wear warning device can more accurately contact the rotor when the distance between the back plate and the rotor becomes shorter than a specified distance, improving the detection accuracy of the wear warning device.

[0106] The brake caliper according to at least one embodiment described above includes, for example, brake pads, brake pad accessories attached to the brake pads, and a caliper body that supports the brake pads so that the brake pads are movable in a direction along the central axis of rotation of a rotor, and the first spring is configured to push the brake pads in a direction away from the rotor by a reaction force that pushes the caliper body. Therefore, as an example, as described above, the first spring moves the brake pads away from the rotor, thereby suppressing the generation of drag resistance due to contact between the brake pads and the rotor when braking is released. This allows the brake caliper to suppress noise generation and reduced fuel economy.

[0107] In the brake caliper, for example, the first spring and the extension extend from the base in a direction away from the rotor, so that, for example, the first spring and the extension can be prevented from interfering with the rotor even if the friction material of the brake pad wears.

[0108] While the embodiments of the present invention have been described above, the above-described embodiments and modifications are merely examples and are not intended to limit the scope of the invention. The above-described embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. Furthermore, the configurations and shapes of each embodiment and each modification can be partially interchanged.

Claims

1. A brake pad accessory comprising: a base configured to be removably attached to a back plate of a brake pad by elastic force; a first spring extending from the base and configured to urge the brake pad in a direction away from a rotor; and an extension extending from the base, wherein the extension has at least one of a wear warning device configured to contact the rotor when the distance between the back plate and the rotor is shorter than a predetermined distance, and a second spring configured to urge the brake pad around the central axis of rotation of the rotor.

2. The brake pad accessory of claim 1, wherein the base has a first wall disposed along a first surface of the backplate, a second wall disposed along a second surface of the backplate opposite the first surface, and a connecting portion connecting the first wall and the second wall, and is configured to hold the backplate between the first wall and the second wall by the elastic force, and the first spring and the extension portion extend from an edge of the first wall.

3. The brake pad accessory of claim 1, wherein the first spring has a first arm extending from the base, a second arm extending from the base, and a pressing portion connecting the first arm and the second arm at a position spaced from the base and configured to press a caliper body, and the extension portion extends from the base between the first arm and the second arm.

4. A brake caliper comprising: a brake pad; a brake pad accessory according to any one of claims 1 to 3 attached to said brake pad; and a caliper body supporting said brake pad movably in a direction along the central axis of rotation of a rotor; wherein said first spring is configured to push said brake pad in a direction away from said rotor by using a reaction force pressing said caliper body.

5. The brake caliper of claim 4, wherein said first spring and said extension extend from said base in a direction away from said rotor.

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