Opposed piston type disc brake system

Abstract

To provide an opposed piston type disc brake device capable of applying a force enough to separate a pad from a rotor by a pad clip, without causing the pad clip to interfere with other members.SOLUTION: An ear part 32 of a pad 6a is engaged with a guide groove 22 provided in a guide wall part 19a of a caliper 5 so as to be movable in an axial direction. A pad clip 7 is used which has: a base part 34 that is substantially U-shaped when viewed in the axial direction, and is fitted into the guide groove 22 so as to surround the ear part 32; a resilient part 35 whose one end part is connected to the base part 34, and that is arranged circumferentially outward with respect to the base part 34 in the guide groove 22; and a pressing part 36 that extends circumferentially inward from the other end part of the resilient part 35, and presses the pad 6a in the axial direction away from a rotor 4 by the elastic force of the resilient part 35.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to an opposed piston type disc brake device.

Background Art

[0002] Disc brake devices are widely used because they have excellent heat dissipation performance and can finely adjust the braking force during running.

[0003] A disc brake device generates braking force by pressing a pair of pads arranged on both axial sides of a rotor that rotates with a wheel against both axial side surfaces of the rotor by pistons. When braking is released, the pistons are pulled back to the inner side of the cylinder by the elastic restoring force of the piston seals, and the pads are pressed in a direction away from the rotor by the axially side surfaces of the rotating and wobbling rotor. Thereby, the pads are separated from the rotor, and a clearance is secured between the pads and the rotor. Unless otherwise specified, the axial direction, radial direction, and circumferential direction refer to the axial direction, radial direction, and circumferential direction of the rotor.

[0004] Even when the pads are pressed by the axially side surfaces of the rotor, the pads may not smoothly move in a direction away from the rotor and may tilt. When the pads tilt in this way, the pads cannot be sufficiently separated from the rotor, and there is a possibility that abrasion between the pads and the rotor becomes a problem.

[0005] In view of such circumstances, it has been considered to incorporate pad clips into the disc brake device and use the elasticity of the pad clips to separate the pads from the rotor when braking is released.

[0006] International Publication No. 2014 / 097098 (Patent Document 1) discloses a structure for opposed-piston disc brake devices that uses a pad clip positioned radially outward of the pad to separate the pad from the rotor when braking is released. Specifically, by making the portion of the pad clip that presses against the outer edge of the pad a tapered surface, the pad is pressed radially inward and also in the axial direction away from the rotor.

[0007] Japanese Patent Publication No. 2016-28216 (Patent Document 2) discloses a structure for a floating-type disc brake device that uses a pad clip fixed to the back surface of the pad to separate the pad from the rotor when braking is released. Specifically, a pad clip that is roughly U-shaped in radial view is placed on the back surface of the pad, one end of the pad clip is fixed to the back surface of the pad, and the other end of the pad clip abuts against a surface of the support that faces away from the rotor in the axial direction. In this way, the elastic force of the pad clip, which is elastically deformed during braking, is used to pull the pad away from the rotor when braking is released. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] International Publication No. 2014 / 097098 [Patent Document 2] Japanese Patent Publication No. 2016-28216 [Overview of the project] [Problems that the invention aims to solve]

[0009] The structure described in International Publication No. 2014 / 097098 uses the tapered surface of the pad clip to compress the pad axially, resulting in insufficient axial pressure and making it difficult to sufficiently separate the pad from the rotor.

[0010] In contrast, the structure described in Japanese Patent Publication No. 2016-28216 allows for sufficient tensile force to be applied to the pad to separate it from the rotor. However, since the pad clip needs to be positioned on the back side of the pad, it is difficult to adopt this structure in configurations such as opposed-piston disc brake systems, where the caliper body is positioned close to the back side of the pad, making it impossible to secure space for the pad clip on the back side of the pad.

[0011] The present invention has been made to solve the above problems, and aims to provide an opposed-piston type disc brake device in which the pad clip can be positioned without interfering with other members, and the pad clip can apply sufficient axial pressure to separate the pad from the rotor. [Means for solving the problem]

[0012] An opposed-piston disc brake device according to one aspect of the present invention comprises a caliper, a pad, and a pad clip. The caliper has two or more cylinders and is fixed to the suspension system. The pad is supported so as to be axially movable relative to the caliper. The pad clip is made of a metal plate and is positioned between the caliper and the pad. The caliper has a guide wall portion adjacent to the outer circumferential side of the pad, which has a circumferential side facing the pad in the circumferential direction and an axial side facing the rotor in the axial direction. The guide wall portion has a guide groove that extends in the circumferential direction and has a circumferential opening on the circumferential side surface and an axial opening on the axial side surface. The pad has lugs that are axially movable and engaged with the guide groove. The pad clip has a substantially U-shape in an axial view and includes a base portion fitted into the guide groove so as to surround the lug portion, an elastic portion whose one end is connected to the base portion and which is located circumferentially outward from the base portion in the guide groove, and a pressing portion extending circumferentially inward from the other end of the elastic portion, which presses the pad in a direction away from the rotor in the axial direction by the elastic force of the elastic portion.

[0013] In one aspect of the present invention, the opposing piston type disc brake device can be configured as a partially cylindrical shape (semi-cylindrical, semi-elongated cylindrical, or semi-elliptical cylindrical) that is substantially C-shaped (including U-shaped) when viewed in the radial direction. Alternatively, the elastic portion can be configured in a roughly J-shape, a roughly V-shape, or a roughly M-shape when viewed radially.

[0014] In one aspect of the present invention, the base portion comprises an outer peripheral plate portion disposed along the outer peripheral wall surface of the guide groove facing radially inward, an inner peripheral plate portion disposed along the inner peripheral wall surface of the guide groove facing radially outward, and a connecting plate portion connecting the outer peripheral plate portion and the inner peripheral plate portion to each other at their respective outer circumferential ends, and the end of the elastic portion on one side can be connected to the end of the connecting plate portion that is furthest from the rotor in the axial direction (anti-rotor side).

[0015] In one aspect of the present invention, the end of the connecting plate portion that is further from the rotor in the axial direction can be positioned closer to the rotor than the ends of the outer peripheral plate portion and the inner peripheral plate portion that are further from the rotor in the axial direction. In this case, the one end of the resilient portion can be positioned closer to the rotor than the end of the outer peripheral plate portion and the inner peripheral plate portion that is further away from the rotor in the axial direction.

[0016] In one aspect of the present invention, the pad clip may further include an outward-bent plate portion that is bent radially outward from the circumferentially inner end of the outer peripheral plate portion, and an inward-bent plate portion that is bent radially inward from the circumferentially inner end of the inner peripheral plate portion. Alternatively, in an opposing piston type disc brake device according to one aspect of the present invention, only one of the outward-bent plate portion and the inward-bent plate portion may be provided, or neither the outward-bent plate portion nor the inward-bent plate portion may be provided.

[0017] In one aspect of the present invention, the outward-bent plate portion can be bent at a right angle to the outer peripheral plate portion, and the inward-bent plate portion can be bent at a right angle to the inner peripheral plate portion. Alternatively, the bending angle of the outward-bent plate portion with respect to the outer peripheral plate portion and the bending angle of the inward-bent plate portion with respect to the inner peripheral plate portion can be made different from each other. Furthermore, the outward-bent plate portion and the inward-bent plate portion can be positioned at the same circumferential position, or they can be positioned offset in the circumferential direction.

[0018] In one aspect of the present invention, the opposing piston type disc brake device is provided with an outer circumferential groove extending in the circumferential direction on the outer peripheral wall surface of the guide groove, and the outer peripheral side plate portion is provided with a claw portion that engages with the outer circumferential groove. Alternatively, the outer radial groove extending in the radial direction is provided on the circumferential side surface portion of the guide wall portion that is radially outward from the circumferential opening of the guide groove, and the outward bent plate portion is provided with a claw portion that engages with the outer radial groove.

[0019] In the opposed piston type disk brake device according to one aspect of the present invention, the outer circumferential groove may be linearly extended in the circumferential direction and the axial position may not change regardless of the circumferential position, or it may be inclined in the direction toward the rotor side or the anti-rotor side with respect to the axial direction as it goes toward the outer side in the circumferential direction. Further, the groove width and the groove depth of the outer circumferential groove may be constant over the entire length in the circumferential direction, or may be made different according to the circumferential position.

[0020] In the opposed piston type disk brake device according to one aspect of the present invention, the outer radial groove may be linearly extended in the radial direction and the axial position may not change regardless of the radial position, or it may be inclined in the direction toward the rotor side or the anti-rotor side with respect to the axial direction as it goes toward the outer side in the radial direction. Further, the groove width and the groove depth of the outer radial groove may be constant over the entire length in the radial direction, or may be made different according to the radial position.

[0021] In the opposed piston type disk brake device according to one aspect of the present invention, an inner circumferential groove extending in the circumferential direction may be provided on the inner peripheral wall surface of the guide concave groove, and a claw portion engaging with the inner circumferential groove may be provided on the inner peripheral side plate portion. Alternatively, an inner radial groove extending in the radial direction may be provided in a portion radially inner than the circumferential opening of the guide concave groove among the circumferential side surfaces of the guide wall portion, and a claw portion engaging with the inner radial groove may be provided on the inward bent plate portion.

[0022] In the opposed piston type disk brake device according to one aspect of the present invention, the inner circumferential groove may be linearly extended in the circumferential direction and the axial position may not change regardless of the circumferential position, or it may be inclined in the direction toward the rotor side or the anti-rotor side with respect to the axial direction as it goes toward the outer side in the circumferential direction. Further, the groove width and the groove depth of the inner circumferential groove may be constant over the entire length in the circumferential direction, or may be made different according to the circumferential position.

[0023] In one aspect of the present invention, the inner radial groove can be made to extend linearly in the radial direction, so that its axial position does not change regardless of its radial position, or it can be made to be inclined toward the rotor side or the anti-rotor side with respect to the axial direction as it moves toward the radially inward side. Furthermore, the groove width and groove depth of the inner radial groove can be kept constant along its entire radial length, or they can be varied depending on the radial position.

[0024] In one aspect of the present invention, the opposing piston type disc brake device is provided with a radially extending outer radial groove on the circumferential side surface of the guide wall portion, in a portion radially outward from the circumferential opening of the guide groove, and the outwardly bent plate portion is provided with a claw portion that engages with the outer radial groove. Furthermore, the inner circumferential wall surface of the guide groove may be provided with an inner circumferential groove extending in the circumferential direction, and the inner circumferential side plate portion may be provided with a claw portion that engages with the inner circumferential groove.

[0025] In one aspect of the present invention, the opposing piston type disc brake device is provided with a radially extending outer radial groove on the circumferential side surface of the guide wall portion, in a portion radially outward from the circumferential opening of the guide groove, and the outwardly bent plate portion is provided with a claw portion that engages with the outer radial groove. Furthermore, the circumferential side surface of the guide wall portion may be provided with an inner radial groove extending in the radial direction inward from the circumferential opening of the guide groove, and the inwardly bent plate portion may be provided with a claw portion that engages with the inner radial groove. Furthermore, the groove bottom surface of the outer radial groove and the groove bottom surface of the inner radial groove can be placed on the same virtual cylindrical surface.

[0026] In one aspect of the present invention, the opposing piston type disc brake device has a notch at the end of the connecting plate that is closer to the rotor in the axial direction, and a part of the resilient portion or a part of the pressing portion can be arranged inside the notch.

[0027] In one aspect of the present invention, the opposing piston type disc brake device may have a pressure-receiving portion that receives torque acting on the pad during braking. If the inwardly bent plate portion is provided with both the claw portion and the pressure-receiving portion, the pressure-receiving portion can be positioned radially inward from the claw portion. If the outward-bent plate portion includes both the claw portion and the pressure-receiving portion, the pressure-receiving portion can be positioned radially outward from the claw portion.

[0028] In one aspect of the present invention, the resilient portion and the pressing portion can be configured so that they do not protrude axially toward the rotor side from the axial opening of the guide groove.

[0029] In one aspect of the present invention, the opposing piston type disc brake device may be equipped with a material removal section. The material removal portion has the function of relieving the stress acting on the elastic portion, and can be, for example, a slit formed in the middle of the elastic portion in the width direction, or notches formed at both ends of the elastic portion in the width direction.

[0030] In one aspect of the present invention, the opposing piston type disc brake device can be pressed by the pressing portion against the axial side surface of the lug portion of the pad. In one aspect of the present invention, a opposed piston type disc brake device may be provided with a bent portion at the circumferentially inner end of the pressing portion, wherein the surface opposite to the rotor in the axial direction is convex. [Effects of the Invention]

[0031] According to one aspect of the present invention, the opposing piston type disc brake device can be positioned without interfering with other components, and the pad clip can provide sufficient axial pressure to separate the pad from the rotor. [Brief explanation of the drawing]

[0032] [Figure 1] Figure 1 is a front view showing a disc brake device of the first example of the embodiment. [Figure 2] Figure 2 is a plan view showing a disc brake device of the first example of the embodiment. [Figure 3] Figure 3 is a side view of the disc brake device of the first embodiment, as seen from the entry side. [Figure 4] Figure 4 is a bottom view showing a disc brake device of the first example of the embodiment. [Figure 5] Figure 5 is a perspective view of the disc brake device of the first embodiment, viewed from the radially outward and inlet side. [Figure 6] Figure 6 is a perspective view of the disc brake device of the first embodiment, viewed from the radially inward and rotating side. [Figure 7] Figure 7 is a cross-sectional view taken along line AA in Figure 2. [Figure 8] Figure 8 is a magnified view of a portion of Figure 7. [Figure 9] Figure 9 is a schematic cross-sectional view of line BB in Figure 8. [Figure 10] Figure 10 is a diagram from Figure 7 with the inner pad and pad clip omitted. [Figure 11] Figure 11(A) is a perspective view of the guide wall portion provided on the outlet side of the inner body, as seen from the circumferential inner side, relating to the first example of the embodiment, and Figure 11(B) is a perspective view showing the state in which a pad clip is attached to the guide groove of the guide wall portion of Figure 11(A). [Figure 12] Figure 12 is a front view showing the inner pad removed from a disc brake device according to the first embodiment. [Figure 13]Figure 13 is a front view showing the inner pad and pad clip removed from a disc brake device according to the first embodiment. [Figure 14] Figure 14 is a cross-sectional view along the CC line in Figure 13. [Figure 15] Figure 15 shows a pad clip removed from a disc brake device according to the first embodiment, which is located axially inward and on the rotation side, where (A) is a front view, (B) is a top view, (C) is a bottom view, (D) is a right side view, and (E) is a left side view. [Figure 16] Figure 16 is a perspective view of a pad clip, which is located on the axially inward and rotating side, removed from a disc brake device according to the first embodiment, and viewed from four directions on the axially outward side. [Figure 17] Figure 17 is a perspective view of a pad clip, which is located axially inward and on the rotation side, removed from a disc brake device according to the first embodiment, and viewed from four directions axially inward. [Figure 18] Figure 18 is a diagram corresponding to Figure 11, showing a second example of the embodiment. [Figure 19] Figure 19 is a perspective view of the guide wall and pad clip shown in Figure 18(B) from the radially inner side, relating to a second example of the embodiment. [Figure 20] Figure 20 is a diagram corresponding to Figure 11, showing a third example of the embodiment. [Figure 21] Figure 21 is a diagram corresponding to Figure 11, showing a fourth example of the embodiment. [Figure 22] Figure 22 is a schematic diagram of a part of the guide wall portion provided on the outlet side of the inner body, as viewed from the axial outside, relating to a fourth embodiment. [Figure 23] Figure 23(A) is a perspective view showing a fifth embodiment in which a pad clip is attached to a guide groove in the guide wall portion provided on the outlet side of the inner body, and Figure 23(B) is a perspective view showing the ear portion of the inner pad engaged with the guide groove in Figure 23(A). [Modes for carrying out the invention]

[0033] [First example of an embodiment] A first example of the embodiment will be described using Figures 1 to 17.

[0034] The opposed-piston type disc brake system 1 in this example is a hybrid type disc brake system that combines a hydraulic opposed-piston type brake mechanism 2, which functions as a service brake, with an electrically operated floating-type brake mechanism 3, which functions as a parking brake. However, the present invention is also applicable to conventional opposed-piston type disc brake systems that do not have a floating-type brake mechanism.

[0035] The following describes the overall structure of the disc brake device 1 in this example, followed by a detailed explanation of the pad clip 7 and its surrounding structure.

[0036] In this specification and in the claims, axial, circumferential, and radial directions refer to the axial, circumferential, and radial directions of the disc-shaped rotor 4 (see Figure 2) that rotates with the wheel, unless otherwise specified. Furthermore, the axial inner side refers to the widthwise center side of the vehicle when assembled to the vehicle, and the axial outer side refers to the widthwise outer side of the vehicle when assembled to the vehicle. Furthermore, the circumferential inner side refers to the circumferential center side of the disc brake device 1, and the circumferential outer side refers to both sides of the disc brake device 1 in the circumferential direction. Furthermore, the entry side refers to the circumferential outer side on which the rotor 4 enters the inside of the caliper 5 when the vehicle is moving forward, and the exit side refers to the circumferential outer side on which the rotor 4 exits the caliper 5 when the vehicle is moving forward.

[0037] [Overall structure of the disc brake system] The disc brake device 1 comprises a caliper 5, a pair of pads 6a and 6b, and four pad clips 7.

[0038] The disc brake device 1 in this example further comprises multiple pistons 8 and 9 (four in the illustrated example), a clamp member 10, and an electric actuator 11.

[0039] The caliper 5 is made of an aluminum alloy or an iron alloy and has a boat-shaped overall form. The caliper 5 constitutes the opposed-piston brake mechanism 2 and is fixed to a suspension device such as a knuckle. The caliper 5 has multiple (four in the illustrated example) cylinders 12.

[0040] Specifically, the caliper 5 has two cylinders 12 in an inner body 13 positioned axially inward from the rotor 4, and two cylinders 12 in an outer body 14 positioned axially outward from the rotor 4. The two cylinders 12 in the inner body 13 and the two cylinders 12 in the outer body 14 are arranged coaxially with respect to each other. The inner body 13 and the outer body 14 are connected by multiple (three in the illustrated example) axially extended connecting parts 15a, 15b, and 15c.

[0041] Each of the cylinders 12 is fitted with pistons 8 and 9 that are axially displaceable. Of the four cylinders 12 provided in the caliper 5, three cylinders 12 are fitted with service-only pistons 8 that operate only when braking with the service brake, and the remaining cylinder 12 is fitted with a dual-purpose piston 9 that operates when braking with either the service brake or the parking brake. The dual-purpose piston 9 is fitted into the cylinder 12 that is located axially inward and on the rotation side of the four cylinders 12.

[0042] A pair of pads 6a and 6b are positioned on both axial sides of the rotor 4 and are supported axially so as to be movable relative to the caliper 5. Specifically, the inner pad 6a, positioned axially inward of the rotor 4, is supported axially so as to be movable relative to the inner body 13. The outer pad 6b, positioned axially outward of the rotor 4, is supported axially so as to be movable relative to the outer body 14.

[0043] The pad clips 7 are made of metal plates and are positioned between the outer ends of the inner pad 6a in the circumferential direction and the inner body 13, and between the outer ends of the outer pad 6b in the circumferential direction and the outer body 14. The pad clips 7 hold the inner pad 6a and the outer pad 6b respectively, preventing them from becoming stuck to the caliper 5, and ensuring smooth axial movement of the inner pad 6a and the outer pad 6b.

[0044] The clamp member 10 constitutes the floating brake mechanism 3 and is supported so as to be axially movable relative to the caliper 5, straddling a pair of pads 6a and 6b from the radially outer side. The clamp member 10 has a claw portion 16 at its axially outer end. The claw portion 16 is positioned between the axially outer surface of the outer pad 6b and the axially inner surface of the outer body 14 of the caliper 5, and presses the outer pad 6b axially inward when braking is performed by the parking brake.

[0045] The electric actuator 11 includes an electric drive unit (MGU) 17 fixed to the axially inward side of the clamp member 10, and a rotation-to-linear motion conversion mechanism (not shown) driven by the electric drive unit 17, which converts rotational motion into linear motion.

[0046] In this example, the disc brake device 1 obtains braking force through a service brake by supplying brake fluid, which is the hydraulic fluid, to all cylinders 12 provided in the caliper 5. Specifically, by supplying brake fluid to all cylinders 12, all pistons 8 and 9 are pushed out of the cylinders 12. Then, a pair of pads 6a and 6b clamp the rotor 4 from both axial sides, thereby obtaining braking force through a service brake.

[0047] Furthermore, the disc brake device 1 in this example obtains braking force from the parking brake by driving the electric actuator 11. Specifically, the electric drive device 17 drives the rotation-to-linear motion conversion mechanism, pushing the dual-purpose piston 9 out of the cylinder 12 and pressing the inner pad 6a against the axially inner surface of the rotor 4. In addition, the reaction force accompanying the pressing displaces the clamp member 10 axially inward relative to the caliper 5, and the claw portion 16 presses the outer pad 6b against the axially outer surface of the rotor 4. As a result, the rotor 4 is clamped from both axial sides by the pair of pads 6a and 6b, and braking force from the parking brake is obtained.

[0048] In this example, when the braking force from the service brake and parking brake is released, the disc brake device 1 uses pad clips 7 to axially separate the inner pad 6a and outer pad 6b from the rotor 4. Specifically, two pad clips 7 positioned axially inward press the inner pad 6a inward, separating the inner pad 6a from the rotor 4. Similarly, two pad clips 7 positioned axially outward press the outer pad 6b outward, separating the outer pad 6b from the rotor 4.

[0049] Next, we will describe in detail the pad clip 7 and its surrounding structure in this example. As mentioned above, the pad clips 7 are positioned between the outer ends of the inner pad 6a in the circumferential direction and the inner body 13, and between the outer ends of the outer pad 6b in the circumferential direction and the outer body 14. Therefore, the structures of the inner body 13 and outer body 14, as well as the structures of the inner pad 6a and outer pad 6b, will be described in detail as peripheral structures of the pad clips 7.

[0050] [Inner body and outer body] The inner body 13 has guide wall portions 19a adjacent to the outer sides of the inner pad 6a in the circumferential direction. The guide wall portions 19a are provided on the outer sides of the axial outer surface of the inner body 13 in the circumferential direction.

[0051] The outer body 14 has guide wall portions 19b adjacent to the outer sides of the outer pad 6b in the circumferential direction. The guide wall portions 19b are provided on the outer sides of the axial inner surface of the outer body 14 in the circumferential direction.

[0052] Each guide wall portion 19a and 19b has a circumferential side surface 20 that faces the inner pad 6a or outer pad 6b in the circumferential direction, and an axial side surface 21 that faces the rotor 4 in the axial direction. Specifically, the guide wall portion 19a provided on the inner body 13 has a circumferential side surface 20 that faces the inner pad 6a in the circumferential direction, and an axial side surface 21 that faces the axial inner surface of the rotor 4 in the axial direction. In contrast, the guide wall portion 19b provided on the outer body 14 has a circumferential side surface 20 that faces the outer pad 6b in the circumferential direction, and an axial side surface 21 that faces the axial outer surface of the rotor 4 in the axial direction.

[0053] Each of the circumferential side surface 20 and the axial side surface 21 is configured as a flat surface. The circumferential side surface 20 and the axial side surface 21 are arranged at approximately right angles to each other.

[0054] The guide walls 19a and 19b have guide grooves 22 that extend in the circumferential direction in their radially intermediate portions. The guide grooves 22 are formed using a cutting tool such as a milling cutter. The guide grooves 22 are rectangular grooves with a rectangular cross-section perpendicular to the axial side surface 21, and have a circumferential opening 23 that opens on the circumferential side surface 20 of the guide walls 19a and 19b, and an axial opening 24 that opens on the axial side surface 21 of the guide walls 19a and 19b. The guide grooves 22 are provided to support the lugs 32, which will be described later, provided on the inner pad 6a and outer pad 6b so that they can move in the axial direction.

[0055] The radial groove width of the guide groove 22 is approximately constant in the circumferential direction. Furthermore, the axial groove depth of the guide groove 22 is also approximately constant in the circumferential direction.

[0056] The guide groove 22 has a flat outer circumferential wall surface 25 facing radially inward, and a flat inner circumferential wall surface 26 facing radially outward. The outer circumferential wall surface 25 and the inner circumferential wall surface 26 are arranged substantially parallel to each other. The guide groove 22 also has a flat axial bottom surface 27.

[0057] The guide wall portions 19a and 19b are provided with radially extending outer radial grooves 28 (see Figure 11(A)) in the portion of the circumferential side surface 20 that is radially outside the circumferential opening 23 of the guide groove 22.

[0058] The outer radial groove 28 extends linearly in the radial direction, and its axial position does not change regardless of its radial position. The axial groove width of the outer radial groove 28 is approximately constant throughout the radial direction, and is about 1 / 8 to 1 / 3 of the axial width of the circumferential side surface 20. The circumferential groove depth of the outer radial groove 28 is also approximately constant throughout the radial direction. The outer radial groove 28 opens on both the radially inward and circumferentially inward sides. The circumferential groove depth of the outer radial groove can be varied depending on the radial position. The outer radial groove can also be opened only on the circumferentially inward side.

[0059] The inner circumferential wall surface 26 of the guide groove 22 is provided with an inner circumferential groove 29 that extends in the circumferential direction (see Figure 11(A)).

[0060] The inner circumferential groove 29 extends linearly in the circumferential direction, and its axial position does not change regardless of its circumferential position. The axial groove width of the inner circumferential groove 29 is approximately constant throughout the circumferential direction, and is about 1 / 8 to 1 / 3 of the axial width of the inner circumferential wall surface 26. Furthermore, the axial groove width of the inner circumferential groove 29 is approximately the same as the axial groove width of the outer radial groove 28. In addition, the radial groove depth of the inner circumferential groove 29 is approximately constant throughout the circumferential direction. The inner circumferential groove 29 opens to the radially outward and circumferentially inward directions, respectively. Note that the radial groove depth of the inner circumferential groove can be varied depending on the circumferential position. Furthermore, the inner circumferential groove can also be opened only to the radially outward direction.

[0061] In this example, the portion of the circumferential side surface 20 of the guide wall portions 19a and 19b that is radially inward from the circumferential opening 23 of the guide groove 22 functions as a torque receiving surface that supports the torque acting on the inner pad 6a and outer pad 6b during braking.

[0062] [Inner pad and outer pad] The inner pad 6a is positioned axially between the rotor 4 and the inner body 13. The outer pad 6b is positioned axially between the rotor 4 and the outer body 14. Each of the inner pad 6a and the outer pad 6b comprises a lining 30 and a metal pressure plate 31 supporting the back surface of the lining 30.

[0063] The pressure plate 31 has ear portions 32 at the radial intermediate portion of both ends in the circumferential direction, which protrude outward in the circumferential direction from the lining 30.

[0064] The lugs 32 are configured in a roughly rectangular plate shape. The radial width of the lugs 32 is slightly smaller than the radial groove width of the guide groove 22. Also, the axial thickness (plate thickness) of the lugs 32 is smaller than the axial groove depth of the guide groove 22.

[0065] The inner pad 6a has a pair of lugs 32 at both outer ends in the circumferential direction that are axially movable with a pair of guide grooves 22 provided in the inner body 13. Similarly, the outer pad 6b has a pair of lugs 32 at both outer ends in the circumferential direction that are axially movable with a pair of guide grooves 22 provided in the outer body 14. As a result, the inner pad 6a and the outer pad 6b are supported relative to the caliper 5 in a way that allows for axial displacement but prevents circumferential and radial displacement.

[0066] The pressure plate 31 has torque transmission portions 33 on the radially inward portion of both circumferentially outer ends, which protrude circumferentially outward from the lining 30. The circumferentially outer end faces of the torque transmission portions 33 are flat and are located circumferentially inward from the circumferentially outer end faces of the lugs 32.

[0067] A shim plate 54 is attached to the back of the pressure plate 31 so as to cover the back surface of the pressure plate 31.

[0068] [Pad Clip] As mentioned above, the disc brake device 1 in this example uses four pad clips 7. Two pad clips 7 positioned axially inward from the rotor 4 have a symmetrical shape with respect to the circumferential direction, and two pad clips 7 positioned axially outward from the rotor 4 also have a symmetrical shape with respect to the circumferential direction. Furthermore, two pad clips 7 positioned on the entry side have a symmetrical shape with respect to the axial direction, and two pad clips 7 positioned on the exit side also have a symmetrical shape with respect to the axial direction. Thus, the shapes of the four pad clips 7 are symmetrical with respect to each other in the axial direction and / or circumferential direction. Therefore, a detailed explanation of the pad clips 7 will be given only for the pad clips 7 positioned axially inward and on the exit side, and the explanation of the remaining pad clips 7 will be omitted.

[0069] The pad clip 7 comprises a base portion 34, an elastic portion 35, and a pressing portion 36. The pad clip 7 is manufactured by press-forming an elastic and corrosion-resistant metal plate, such as a stainless steel plate, and has a uniform overall plate thickness.

[0070] The base portion 34 has a roughly U-shape when viewed axially and is provided on the circumferential inner half of the radially intermediate portion of the pad clip 7. The base portion 34 is fitted into the guide groove 22 so as to surround the ear portion 32 of the inner pad 6a. The base portion 34 holds the ear portion 32 of the inner pad 6a and ensures smooth axial movement of the inner pad 6a relative to the caliper 5.

[0071] The base portion 34 has an outer peripheral plate portion 37 disposed along the outer peripheral wall surface 25 of the guide groove 22, an inner peripheral plate portion 38 disposed along the inner peripheral wall surface 26 of the guide groove 22, and a connecting plate portion 39 that connects the outer peripheral plate portion 37 and the inner peripheral plate portion 38 to each other at their respective outer ends in the circumferential direction.

[0072] The base portion 34 is fitted snugly inside the guide groove 22 by elastically pressing the outer peripheral plate portion 37 against the outer peripheral wall surface 25 and elastically pressing the inner peripheral plate portion 38 against the inner peripheral wall surface 26.

[0073] The outer peripheral plate portion 37 has a flat plate shape and an axial width that is approximately the same as that of the outer peripheral wall surface 25.

[0074] The inner circumferential plate portion 38 has a flat shape and an axial width that is approximately the same as that of the inner circumferential wall surface 26. The circumferential length of the inner circumferential plate portion 38 is the same as that of the circumferential length of the outer circumferential plate portion 37. The inner circumferential plate portion 38 is arranged approximately parallel to the outer circumferential plate portion 37.

[0075] In this example, the inner circumferential plate portion 38 has a tongue-shaped claw portion 40. The claw portion 40 is formed by creating a roughly U-shaped cut in the circumferential middle part of the inner circumferential plate portion 38 and bending the inner portion of the cut radially inward. The claw portion 40 extends radially inward as it moves axially outward. With the base portion 34 fitted inside the guide groove 22, the claw portion 40 engages axially with the inner circumferential groove 29 provided on the inner circumferential wall surface 26. This prevents the inner circumferential plate portion 38 from being displaced axially outward with respect to the inner circumferential wall surface 26.

[0076] The connecting plate portion 39 has a flat plate shape. The radially outer end of the connecting plate portion 39 is connected to the circumferentially outer end of the outer peripheral plate portion 37 at approximately a right angle, and the radially inner end of the connecting plate portion 39 is connected to the circumferentially outer end of the inner peripheral plate portion 38 at approximately a right angle.

[0077] The connecting plate portion 39 has a rotor-side notch 41 corresponding to the notch described in the claims at its axially outer end, which is located on the side closer to the rotor 4 in the axial direction, and an anti-rotor-side notch 42 at its axially inner end, which is located on the side further away from the rotor 4 in the axial direction. The rotor-side notch 41 and the anti-rotor-side notch 42 are formed in a range extending from the radially inner end to the radially outer end of the connecting plate portion 39. The radial length of the rotor-side notch 41 is greater than the radial width of the pressing portion 36.

[0078] The axial width of the connecting plate portion 39 is smaller than the axial widths of the outer peripheral plate portion 37 and the inner peripheral plate portion 38, respectively, by forming the rotor-side notch 41 and the non-rotor-side notch 42 in the connecting plate portion 39, and is approximately 1 / 3 to 2 / 3 of the axial widths of the outer peripheral plate portion 37 and the inner peripheral plate portion 38, respectively. In the illustrated example, the axial width of the rotor-side notch 41 is made larger than the axial width of the non-rotor-side notch 42, but they can also be made to be the same size.

[0079] The resilient section 35 is elastically deformed by the inner pad 6a during braking by the service brake and parking brake, and stores resilient energy that is used to separate the inner pad 6a from the rotor 4.

[0080] The resilient portion 35 is located on the circumferentially outer half of the radially intermediate portion of the pad clip 7, and when the pad clip 7 is attached, it is positioned circumferentially outward from the base portion 34 within the guide groove 22. In other words, in this example, not only the base portion 34 that holds the ear portion 32, but also the resilient portion 35 that stores resilient energy is housed in the guide groove 22 of the pad clip 7.

[0081] In this example, the resilient portion 35 has a roughly C-shape when viewed radially and is configured as a partially cylindrical (roughly semi-cylindrical) shape. The resilient portion 35 is composed of a circumferential extension portion 35a that extends circumferentially outward from the axially inward end of the connecting plate portion 39 that constitutes the base portion 34, and a curved portion 35b that curves in an arc shape from the circumferentially outward end of the circumferential extension portion 35a in the direction axially outward as it moves circumferentially outward, and then curves in an arc shape in the direction circumferentially inward as it moves axially outward. However, the shape of the resilient portion is not limited to the above shape, and can also be configured as a roughly J-shape, roughly V-shape, or roughly M-shape when viewed radially.

[0082] The circumferential inner end of the circumferential extension 35a, which constitutes one end of the resilient portion 35, is connected to the axially inner end of the connecting plate portion 39. The circumferential inner end of the circumferential extension 35a is located axially outward from the axially inner ends of the outer peripheral plate portion 37 and the inner peripheral plate portion 38, which constitute the base portion 34. Therefore, when the axially inner ends of the outer peripheral plate portion 37 and the inner peripheral plate portion 38, which constitute the base portion 34, are abutted against the axial bottom surface 27 of the guide groove 22, a gap is formed between the axially inner surface of the circumferential extension 35a and the axial bottom surface 27. In this example, tongue-shaped abutting pieces 53a and 53b, which are provided in the circumferential middle portion of the axially inner ends of the outer peripheral plate portion 37 and the inner peripheral plate portion 38, are abutted against the axial bottom surface 27 of the guide groove 22, but the abutting pieces can be omitted.

[0083] The circumferentially inner end of the curved portion 35b, which constitutes the other end of the resilient portion 35, is connected to the circumferentially outer end of the pressing portion 36. The circumferentially inner end of the curved portion 35b is positioned axially outward from the axially outer end of the connecting plate portion 39.

[0084] The pressing portion 36 extends circumferentially inward from the other end of the elastic portion 35. In this example, in the free state of the pad clip 7 (elastic portion 35), the pressing portion 36 is slightly inclined axially inward as it moves circumferentially inward. Therefore, in the free state of the pad clip 7, the pressing portion 36 approaches the axial bottom surface 27 of the guide groove 22 as it moves circumferentially inward.

[0085] In this example, the circumferential outer portion of the pressing portion 36 is positioned inside the rotor-side notch 41 provided in the connecting plate portion 39. In other words, the pressing portion 36 extends circumferentially through the rotor-side notch 41. Therefore, most of the pressing portion 36 is positioned in the portion between the outer peripheral plate portion 37 and the inner peripheral plate portion 38 in the radial direction. The pressing portion 36 presses the inner pad 6a in the axial direction, which is away from the rotor 4 in the axial direction, by the elasticity of the resilient portion 35.

[0086] In this example, the axially inner surface of the circumferentially inner portion of the pressing portion 36 presses the axially outer surface of the ear portion 32 of the inner pad 6a toward the axially inner side.

[0087] The pressing portion 36 has a substantially L-shape (including a J-shape) when viewed radially, and is equipped with a bent portion 43 on its axially inner side. In this example, the convex surface formed by the axially inner surface of the bent portion 43 is brought into contact with the axially outer surface of the ear portion 32 of the inner pad 6a, thereby pressing the ear portion 32 axially inward.

[0088] A hollowed-out section 44 is formed in the area extending from one side of the elastic section 35 to the circumferentially inner part of the pressing section 36. The hollowed-out section 44 has the function of relieving the stress acting on the elastic section 35 and the pressing section 36. In this example, the hollowed-out section 44 is composed of a slit (through hole) formed in the widthwise middle part of the elastic section 35 and the pressing section 36.

[0089] Neither the resilient portion 35 nor the pressing portion 36 protrudes axially outward from the axial opening 24 of the guide groove 22. In other words, the shape of the resilient portion 35 changes between braking and non-braking states, and the axial position of the pressing portion 36 changes between braking and non-braking states, but neither the resilient portion 35 nor the pressing portion 36 protrudes axially outward from the axial opening 24 of the guide groove 22, regardless of whether it is braking or non-braking.

[0090] The pad clip 7 in this example further comprises an outward-bent plate portion 45 and an inward-bent plate portion 46.

[0091] The outward-bent plate portion 45 bends approximately at a right angle radially outward from the circumferentially inner end of the outer peripheral plate portion 37 that constitutes the base portion 34, and covers the portion of the circumferential side surface 20 of the guide wall portion 19a that is radially outward from the circumferential opening 23. The axial width of the outward-bent plate portion 45 is smaller than the axial width of the outer peripheral plate portion 37, and is about 1 / 4 to 2 / 3 of the axial width of the outer peripheral plate portion 37. In this example, the outward-bent plate portion 45 is connected to the axially inner end of the circumferentially inner end of the outer peripheral plate portion 37.

[0092] The inwardly bent plate portion 46 bends approximately at a right angle radially inward from the circumferentially inward end of the inner circumferential side plate portion 38 that constitutes the base portion 34, and covers the portion of the circumferential side surface 20 of the guide wall portion 19a that is radially inward from the circumferential opening 23. The axial width of the inwardly bent plate portion 46 is the same as the axial width of the inner circumferential side plate portion 38.

[0093] In this example, the outward-bent plate portion 45 and the inward-bent plate portion 46 are arranged substantially parallel to each other and are located at the same circumferential position. That is, the circumferential outer surface of the outward-bent plate portion 45 and the circumferential outer surface of the inward-bent plate portion 46 are located on the same virtual plane.

[0094] In this example, the outward-bent plate portion 45 has a tongue-shaped claw portion 47. The claw portion 47 extends axially outward from the radially outer end of the outward-bent plate portion 45. The claw portion 47 extends circumferentially outward as it moves axially outward. The claw portion 47 fits its base portion 34 into the inside of the guide groove 22, and with the outward-bent plate portion 45 covering the circumferential side surface 20 of the guide wall portion 19a, it engages axially with the outer radial groove 28 provided on the circumferential side surface 20. This prevents the outward-bent plate portion 45 from being displaced axially outward relative to the circumferential side surface 20.

[0095] In this example, the inwardly bent plate portion 46 has a pressure receiving portion 48 that receives torque acting on the inner pad 6a during braking. The pressure receiving portion 48 covers the torque receiving surface provided on the circumferential side surface 20 of the guide wall portion 19a, and during braking, the circumferential end surface of the torque transmission portion 33 of the inner pad 6a abuts against it.

[0096] In this example, the pad clip 7, having the configuration described above, always has the bent portion 43 provided on the pressing portion 36 in contact with the axial outer surface of the ear portion 32 of the inner pad 6a or the axial inner surface of the ear portion 32 of the outer pad 6b.

[0097] In this example, when braking is performed using the service brake and parking brake, the inner pad 6a and outer pad 6b are pressed by the pistons 8 and 9 in the axial direction toward the rotor 4. As a result, the pressing portion 36 that contacts the lug portion 32 is displaced axially toward the rotor 4, causing elastic deformation to occur in the resilient portion 35. Specifically, the resilient portion 35 undergoes elastic deformation such that the axial distance between one end and the other end widens. This stores resilient energy in the resilient portion 35.

[0098] In this example, when the brake is released, the pad clip 7, when the pistons 8 and 9 are pulled back to the rear of the cylinder 12 by the elastic restoring force of a piston seal (not shown), presses the inner pad 6a or outer pad 6b in the axial direction away from the rotor 4 via the pressing part 36 by the elastic restoring force of the resilient part 35. This moves the inner pad 6a and outer pad 6b to a position where drag with the rotor 4 can be prevented.

[0099] According to the opposed-piston type disc brake device 1 of this example, the pad clip 7 can be positioned without interfering with other components, and the pad clip 7 can apply sufficient axial pressure to separate the inner pad 6a and the outer pad 6b from the rotor 4. In other words, according to the disc brake device 1 of this example, the elastic force of the resilient portion 35 constituting the pad clip 7 allows the inner pad 6a or outer pad 6b to be pressed only in the direction away from the rotor 4 in the axial direction via the pressing portion 36. Therefore, compared to the conventional structure described above, which uses component forces to press in the axial direction, a larger axial pressing force can be applied to the inner pad 6a or outer pad 6b.

[0100] In particular, in the disc brake device 1 of this example, when the braking force from the parking brake is released, the two pad clips 7 positioned axially outward need to move the clamp member 10 axially outward relative to the caliper 5 in order to move the outer pad 6b axially outward. Therefore, a large force is required to move the outer pad 6b axially outward, but with the pad clips 7 of this example, a large axial pressing force can be applied to the outer pad 6b, making it possible to sufficiently separate the outer pad 6b from the rotor 4, and effectively preventing drag between the outer pad 6b and the rotor 4.

[0101] Furthermore, when the pad clip 7 is attached, not only the base 34 that holds the ear portion 32, but also the resilient portion 35 is positioned inside the guide groove 22. In addition, by extending the pressing portion 36 circumferentially inward from the resilient portion 35, the pressing portion 36 is also positioned inside the guide groove 22. In this way, both the resilient portion 35 and the pressing portion 36 are housed in the guide groove 22 for engaging the ear portion 32. Therefore, even though the inner body 13 is positioned close to the back side (axially inward) of the inner pad 6a, and the outer body 14 is positioned close to the back side (axially outward) of the outer pad 6b, the pad clip 7 can be positioned without interfering with other components.

[0102] Furthermore, in this example, the shape and dimensions of each part of the resilient portion 35 and the pressing portion 36 are regulated so that they do not protrude axially outward from the axial opening 24 of the guide groove 22, thereby preventing the pad clip 7 from interfering with the rotor 4.

[0103] Furthermore, since the resilient portion 35 is positioned circumferentially outward from the base portion 34 within the guide groove 22, the circumferential distance from the resilient portion 35 to the lug portion 32 can be increased. This suppresses the stress generated by the elastic deformation of the resilient portion 35 during braking. As a result, the pad clip 7 does not undergo plastic deformation from the lining 30 from a new state to a worn state, and a stable pressing force can be applied to the inner pad 6a or outer pad 6b.

[0104] Furthermore, in this example, since a portion of the resilient portion 35 and the pressing portion 36 is provided with a thinned portion 44 consisting of a slit, the stress generated in the resilient portion 35 and the pressing portion 36 can be suppressed more effectively.

[0105] In this example, the claw portion 47 provided on the outward-bent plate portion 45 is axially engaged with the outer radial groove 28 provided on the circumferential side surfaces 20 of the guide wall portions 19a and 19b, and the claw portion 40 provided on the inner circumferential plate portion 38 is axially engaged with the inner circumferential groove 29 provided on the inner circumferential wall surface 26 of the guide groove 22. Therefore, the pad clip 7 can be prevented from tilting (rotating) due to the reaction force when the inner pad 6a or outer pad 6b is pressed by the pressing portion 36. Thus, the posture of the pad clip 7 can be stabilized, and a stable pressing force can be applied to the inner pad 6a or outer pad 6b.

[0106] Furthermore, in this example, when the brake is released, the bent portion 43 of the pressing portion 36 of the pad clip 7 can press against the axial side surface of the ear portion 32, thus keeping the contact position between the ear portion 32 and the pressing portion 36 constant. This suppresses variations in the direction and magnitude of the pressing force applied to the inner pad 6a and the outer pad 6b.

[0107] In this example, the guide groove 22 accommodates not only the base 34 that holds the ear portion 32, but also the resilient portion 35. As a result, the circumferential dimension of the guide groove 22 is longer than when using a pad clip without the resilient portion 35, and consequently, the thickness of the outer circumferential ends of the inner body 13 and outer body 14 decreases. However, the thickness of the outer circumferential ends of the inner body 13 and outer body 14 has a sufficiently small effect on the rigidity and strength of the caliper 5. Therefore, even if the circumferential dimension of the guide groove 22 is longer to accommodate the resilient portion 35, the strength and rigidity of the caliper 5 can be sufficiently ensured.

[0108] [Second example of an embodiment] A second example of the embodiment will be described with reference to Figures 18 and 19. In this example, components similar to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and detailed descriptions are omitted.

[0109] In this example, only the structure of the pad clip 7a and the structure of the guide wall portion 19a (19b) differ from the structure of the first example of the embodiment.

[0110] In this example, instead of providing radially extending outer radial grooves 28 (see Figure 11(A)) on the circumferential side surface 20 of the guide wall portion 19a (19b), the outer circumferential grooves 49 are provided on the outer circumferential wall surface 25 of the guide groove 22.

[0111] The outer circumferential groove 49 extends linearly in the circumferential direction, and its axial position does not change regardless of its circumferential position. The axial groove width of the outer circumferential groove 49 is approximately constant throughout the circumferential direction, and is about 1 / 8 to 1 / 3 of the axial width of the outer circumferential wall surface 25. Furthermore, the axial groove width and axial position of the outer circumferential groove 49 are approximately the same as those of the inner circumferential groove 29. In addition, the radial groove depth of the outer circumferential groove 49 is approximately constant throughout the circumferential direction. The outer circumferential groove 49 opens to the radially inward side and to the circumferential inward side, respectively. Note that the radial groove depth of the outer circumferential groove can be varied depending on the circumferential position. Furthermore, the outer circumferential groove can also be opened only to the radially inward side.

[0112] In this example, the outward-bent plate portion 45a of the pad clip 7a does not have a claw portion 47 (see Figure 11(B)), and the entire structure is flat. The axial width of the outward-bent plate portion 45a is the same as the axial width of the outer peripheral plate portion 37a.

[0113] The pad clip 7a in this example has a tongue-shaped claw portion 50 on the outer peripheral plate portion 37a. The claw portion 50 is formed by creating a roughly U-shaped cut in the circumferential middle part of the outer peripheral plate portion 37a and bending the inner portion of the cut radially outward. The claw portion 50 extends radially outward as it moves axially outward. With the base portion 34 fitted inside the guide groove 22, the claw portion 50 engages axially with the outer circumferential groove 49 provided on the outer peripheral wall surface 25. This prevents the outer peripheral plate portion 37a from being displaced axially outward with respect to the outer peripheral wall surface 25.

[0114] In this example, the claw portion 50 provided on the outer peripheral plate portion 37a is axially engaged with the outer circumferential groove 49 provided on the outer peripheral wall surface 25 of the guide groove 22, and the claw portion 40 provided on the inner peripheral plate portion 38 is axially engaged with the inner circumferential groove 29 provided on the inner peripheral wall surface 26 of the guide groove 22. Therefore, the pad clip 7a can be prevented from tilting due to the reaction force when the inner pad 6a or outer pad 6b is pressed by the pressing portion 36. As a result, the posture of the pad clip 7a can be stabilized, and a stable pressing force can be applied to the inner pad 6a or outer pad 6b.

[0115] Furthermore, since the outer circumferential groove 49 and the inner circumferential groove 29 can be machined simultaneously by cutting, this is advantageous in reducing processing costs. The other configurations and effects are the same as in the first example of the embodiment.

[0116] [Third example of an embodiment] A third embodiment will be described with reference to Figure 20. In this example, components similar to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and detailed descriptions are omitted.

[0117] In this example, only the structure of the pad clip 7b and the structure of the guide wall portion 19a (19b) differ from the structure of the first example of the embodiment.

[0118] In this example, instead of providing an inner circumferential groove 29 (see Figure 11(A)) on the inner circumferential wall surface 26 of the guide groove 22 of the guide wall portion 19a (19b), an inner radial groove 51 extending in the radial direction is provided on the circumferential side surface 20 in the portion radially inward from the circumferential opening 23 of the guide groove 22.

[0119] The inner radial groove 51 extends linearly in the radial direction, and its axial position does not change regardless of its radial position. The axial groove width of the inner radial groove 51 is approximately constant along the radial direction, and is about 1 / 8 to 1 / 3 of the axial width of the circumferential side surface 20. Furthermore, the axial groove width and axial position of the inner radial groove 51 are approximately the same as those of the outer radial groove 28. In addition, the circumferential groove depth of the inner radial groove 51 is approximately constant along the radial direction. The inner radial groove 51 opens on the radially outward side and the circumferentially inward side, respectively. Note that the circumferential groove depth of the inner radial groove can be varied depending on the radial position. Furthermore, the inner radial groove can also be opened only on the circumferentially inward side.

[0120] In this example, the inner circumferential plate portion 38a of the pad clip 7b does not have a claw portion 40 (see Figure 11(B)), and the entire structure is flat.

[0121] The pad clip 7b in this example has a tongue-shaped claw portion 52 on the inwardly bent plate portion 46a. The claw portion 52 extends axially outward from the radially inward end of the inwardly bent plate portion 46a. The claw portion 52 extends circumferentially outward as it moves axially outward. The claw portion 52 fits its base portion 34 into the inside of the guide groove 22, and with the inwardly bent plate portion 46a covering the circumferential side surface 20 of the guide wall portion 19a, it engages axially with the inner radial groove 51 provided on the circumferential side surface 20. This prevents the inwardly bent plate portion 46a from being displaced axially outward relative to the circumferential side surface 20. The inwardly bent plate portion 46a has the claw portion 52 but does not have a flat pressure receiving portion 48 (see Figure 23(A)).

[0122] In this example, the claw portion 47 provided on the outward-bent plate portion 45 is axially engaged with the outer radial groove 28 provided on the circumferential side surface 20 of the guide wall portions 19a and 19b, and the claw portion 52 provided on the inward-bent plate portion 46a is axially engaged with the inner radial groove 51 provided on the circumferential side surface 20. As a result, the pad clip 7b can be prevented from tilting due to the reaction force when the inner pad 6a or outer pad 6b is pressed by the pressing portion 36. Therefore, the posture of the pad clip 7b can be stabilized, and a stable pressing force can be applied to the inner pad 6a or outer pad 6b.

[0123] Furthermore, since the outer radial groove 28 and the inner radial groove 51 can be machined by moving the cutting tool linearly in the radial direction, this is advantageous in reducing the number of machining steps. The other configurations and effects are the same as in the first example of the embodiment.

[0124] [Fourth example of an embodiment] A fourth embodiment will be described with reference to Figures 21 and 22. In this example, components similar to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and detailed descriptions are omitted.

[0125] This example is a modification of the third embodiment. In this example, the bottom surfaces of the outer radial groove 28a and the inner radial groove 51a provided on the circumferential side surface 20 of the guide wall portion 19a (19b) are configured as a partially cylindrical surface. Furthermore, the bottom surfaces of the outer radial groove 28a and the inner radial groove 51a are located on the same virtual cylindrical surface C.

[0126] In this example, since the outer radial groove 28a and the inner radial groove 51a can be machined simultaneously by cutting processes such as milling, the number of processing steps and processing costs can be reduced. The other configurations and effects are the same as those in the first and third embodiments.

[0127] [Fifth example of the embodiment] A fifth embodiment will be described with reference to Figure 23. In this example, components similar to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and detailed descriptions are omitted.

[0128] This example is a modified version of the third embodiment. In this example, the pad clip 7c has not only a tongue-shaped claw portion 52 but also a pressure-receiving portion 48 on the inwardly bent plate portion 46b.

[0129] The claw portion 52 is provided on the radially outer portion of the inwardly bent plate portion 46b, and extends in a direction that is circumferentially outward as it moves axially outward. The pressure receiving portion 48 is provided on the radially inner portion of the inwardly bent plate portion 46b.

[0130] In this example, since the inwardly bent plate portion 46b of the pad clip 7c is equipped with a pressure receiving portion 48, the pressure receiving portion 48 can protect the circumferential side surface 20 of the guide wall portion 19a. The other configurations and effects are the same as those in the first and third embodiments.

[0131] Although embodiments of the present invention have been described above, the present invention is not limited thereto and can be modified as appropriate without departing from the technical spirit of the invention. Furthermore, the structures of each example of the embodiments can be combined as appropriate, as long as no contradictions arise.

[0132] When implementing the present invention, the shapes of the elastic portion, claw portion, etc., that constitute the pad clip are not limited to the structure of each example of the embodiment and can be changed as appropriate. Furthermore, the total length, depth, and formation position of the outer radial groove, inner radial groove, outer circumferential groove, and inner circumferential groove are not limited to the structure of each example of the embodiment and can be changed as appropriate. [Explanation of symbols]

[0133] 1. Disc brake system 2. Opposed piston type brake mechanism 3. Floating brake mechanism 4 rotors 5 Caliper 6a Inner Pad 6b Outer pad 7, 7a, 7b, 7c Pad Clips 8 Service-only pistons 9. Dual-purpose piston 10 Clamp member 11 Electric Actuator 12 cylinders 13 Inner Body 14 Outer Body 15a, 15b, 15c connection part 16. Nail part 17 Electric drive system 19a, 19b Guide wall section 20 Circumferential side 21 Axial side 22 Guide grooves 23 Circumferential opening 24 Axial opening 25 Outer wall surface 26 Inner circumferential wall surface 27 Axial bottom surface 28, 28a Outside radial groove 29 Inner circumferential groove 30 lining 31 Pressure Plate 32 Ears 33 Torque transmission section 34 Base 35. Explosive Unit 35a Circumferential extension part 35b Curved section 36 Pressing part 37, 37a Outer side plate 38, 38a Inner side plate part 39. Connecting plate section 40 Claw part 41 Rotor-side notch 42. Notch on the side opposite the rotor 43. Bending section 44 Thinning section 45, 45a Outward bent plate part 46, 46a, 46b Inward bent plate section 47. Nail area 48 Pressure-receiving section 49 Outer circumferential groove 50 Nail part 51, 51a Inner radial groove 52 Claw part 53a, 53b Abutment piece 54 Shim Plate

Claims

1. A caliper having two or more cylinders and fixed to a suspension system, A pad supported so as to be axially movable relative to the caliper, The caliper and the pad are positioned together and include a metal plate pad clip, The caliper has a guide wall portion adjacent to the circumferentially outer side of the pad, which has a circumferential side facing the pad in the circumferential direction and an axial side facing the rotor in the axial direction, respectively. The guide wall portion has a guide groove that extends in the circumferential direction and has a circumferential opening on the circumferential side surface and an axial opening on the axial side surface, respectively. The pad has an ear portion that is axially movable and engaged with the guide groove, The pad clip has a substantially U-shape in an axial view and includes a base portion fitted into the guide groove so as to surround the lug portion, a resilient portion having one end connected to the base portion and positioned circumferentially outward from the base portion within the guide groove, and a pressing portion extending circumferentially inward from the other end of the resilient portion, which presses the pad away from the rotor in the axial direction by the elastic force of the resilient portion. Opposed piston type disc brake system.

2. The opposing piston type disc brake device according to claim 1, wherein the resilient portion is configured as a partially cylindrical shape that is substantially C-shaped when viewed radially.

3. The base portion comprises an outer peripheral plate portion disposed along the outer peripheral wall surface facing radially inward within the guide groove, an inner peripheral plate portion disposed along the inner peripheral wall surface facing radially outward within the guide groove, and a connecting plate portion connecting the outer peripheral plate portion and the inner peripheral plate portion, respectively, The end of the resilient portion on one side is connected to the end of the connecting plate portion that is furthest from the rotor in the axial direction. The opposed piston type disc brake device described in claim 1.

4. The pad clip further comprises an outward-bent plate portion that is bent radially outward from the circumferentially inner end of the outer peripheral plate portion, and an inward-bent plate portion that is bent radially inward from the circumferentially inner end of the inner peripheral plate portion. The opposed piston type disc brake device described in claim 3.

5. The outer circumferential groove extending in the circumferential direction is provided on the outer circumferential wall surface of the guide groove, and the outer circumferential side plate portion is provided with a claw portion that engages with the outer circumferential groove, or the outer radial groove extending in the radial direction is provided on the circumferential side surface portion of the guide wall portion that is radially outward from the circumferential opening of the guide groove, and the outward bent plate portion is provided with a claw portion that engages with the outer radial groove. The opposed piston type disc brake device described in claim 4.

6. The inner circumferential wall surface of the guide groove is provided with an inner circumferential groove extending in the circumferential direction, and the inner circumferential side plate portion is provided with a claw portion that engages with the inner circumferential groove, or the circumferential side surface portion of the guide wall portion is provided with an inner radial groove extending in the radial direction inward from the circumferential opening of the guide groove, and the inwardly bent plate portion is provided with a claw portion that engages with the inner radial groove. The opposed piston type disc brake device described in claim 4.

7. A radially extending outer radial groove is provided on the circumferential side surface of the guide wall portion, in the portion radially outward from the circumferential opening of the guide groove, and a claw portion is provided on the outwardly bent plate portion that engages with the outer radial groove. The inner circumferential wall surface of the guide groove is provided with an inner circumferential groove extending in the circumferential direction, and the inner circumferential side plate portion is provided with a claw portion that engages with the inner circumferential groove. The opposed piston type disc brake device described in claim 4.

8. A radially extending outer radial groove is provided on the circumferential side surface of the guide wall portion, in the portion radially outward from the circumferential opening of the guide groove, and a claw portion is provided on the outwardly bent plate portion that engages with the outer radial groove. A radially extending inner radial groove is provided on the circumferential side surface of the guide wall portion, in the portion radially inward from the circumferential opening of the guide groove, and a claw portion is provided on the inwardly bent plate portion that engages with the inner radial groove. The groove bottom surface of the outer radial groove and the groove bottom surface of the inner radial groove are located on the same virtual cylindrical surface. The opposed piston type disc brake device described in claim 4.

9. The connecting plate portion has a notch at the end closest to the rotor in the axial direction. A part of the resilient portion or a part of the pressing portion is located inside the notch. The opposed piston type disc brake device described in claim 3.

10. The opposing piston type disc brake device according to claim 4, wherein the inward-bent plate portion and / or the outward-bent plate portion has a pressure-receiving portion that receives torque acting on the pad during braking.

11. The opposing piston type disc brake device according to claim 1, wherein neither the resilient portion nor the pressing portion protrudes axially toward the rotor side from the axial opening of the guide groove.

12. The opposing piston type disc brake device according to claim 1, wherein the resilient portion is provided with a portion for removing excess material.

13. The opposing piston type disc brake device according to claim 1, wherein the pressing portion presses the axial side surface of the lug portion of the pad.

Images