Braking device

Abstract

The present invention provides a braking device that effectively reduces rust formation on the slide pin and the surrounding area of ​​the slide pin. [Solution] The braking device includes a cylindrical pin boot (31) through which a slide pin (30), one end of which is connected to the caliper body and the other end of which is connected to the caliper mount, is inserted. The pin boot (31) has a coil spring (321) and an elastic cover (310) that covers the coil spring (321).

Description

Technical Field

[0001] The present disclosure relates to a braking device. Background Art

[0002] In the caliper-type disc brake disclosed in Patent Document 1, a guide pin is inserted through a coil spring disposed in a guide hole formed in a part of the caliper, and the outer periphery of the guide pin is engaged with the inner periphery of the coil spring. Prior Art Literature Patent Literature

[0003] Patent Document 1 Japanese Unexamined Patent Publication No. 2010-121705 Summary of the Invention Problem to be Solved by the Invention

[0004] In the braking device disclosed in Patent Document 1, the opening of the guide hole through which the guide pin (hereinafter referred to as a slide pin) is inserted is not covered. Waterproof performance is not ensured for the slide pin and the hole through which the slide pin is inserted, so rust is likely to occur. An object of one aspect of the present disclosure is to provide a braking device that suitably reduces the occurrence of rust on the slide pin and the peripheral portion thereof. Means for Solving the Problem

[0005] To solve the above problems, a braking device according to one aspect of the present disclosure comprises a caliper body having a cylinder portion that slidably houses a piston, a claw portion that is positioned opposite to the cylinder portion via a rotating body that rotates with a wheel, and a bridge portion that spans the rotating body and connects the cylinder portion and the claw portion, and a caliper mount to which the other end of a slide pin, one end of which is connected to the caliper body, is connected, and which supports the caliper body so as to be slidable in the axial direction of the rotating body along the slide pin, wherein the braking device comprises a pin boot having a cylindrical shape and through which the slide pin is inserted, and the pin boot has a coil spring and an elastic cover that covers the coil spring. [Effects of the Invention]

[0006] According to one aspect of this disclosure, a braking device can be provided that preferably reduces the occurrence of rust on the slide pin and the hole through which the slide pin is inserted. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic diagram showing one example of the configuration of a braking device according to one embodiment of the present disclosure. [Figure 2] This is a perspective view of a pin boot according to one embodiment of the present disclosure. [Figure 3] This is an axial cross-sectional view of a pin boot according to one embodiment of the present disclosure. [Modes for carrying out the invention]

[0008] Figure 1 is a schematic diagram showing an example configuration of a braking device according to one embodiment of the present disclosure. The braking device 1 shown in Figure 1 is a floating caliper type disc brake. The braking device 1 comprises a caliper body 10, a caliper mount 20, a piston 40, an inner pad 50, and an outer pad 51. A disc rotor R, which rotates with the vehicle's wheel, is positioned between the inner pad 50 and the outer pad 51. The disc rotor R is an example of a rotating body. Hereinafter, the side with the inner pad 50 will be referred to as the inner side, and the side with the outer pad 51 will be referred to as the outer side, along the axial direction of the disc rotor R.

[0009] The caliper mount 20 is a metal component that is fixed to the vehicle body on the inner side of the disc rotor R. The caliper body 10 includes a cylinder portion 11, a claw portion 12, a bridge portion 13, a slide pin 30, and a pin boot 31. A piston 40 is slidably housed in the cylinder section 11. The claw portion 12 is positioned opposite the cylinder portion 11 via the disc rotor R. The bridge section 13 straddles the disc rotor R and connects the cylinder section 11 and the claw section 12.

[0010] The slide pin 30 extends axially from the disc rotor R, with one end connected to the caliper body 10 and the other end connected to the caliper mount 20. For example, the other end of the slide pin 30 is fitted into a hole provided in the caliper mount 20. The caliper body 10 can move relative to the caliper mount 20 along the axial direction of the slide pin 30. The pin boot 31 has a cylindrical shape, with the slide pin 30 inserted inside. The slide pin 30 is supported by the pin boot 31 so as to be axially slidable.

[0011] Figure 2 is a perspective view of a pin boot according to one embodiment of the present disclosure. Figure 3 is an axial cross-sectional view of a pin boot according to one embodiment of the present disclosure. As shown in Figure 2, the pin boot 31 has an elastic cover 310 made of an elastic material such as rubber. A continuous spiral fold is formed on the side surface 311 of the elastic cover 310.

[0012] As shown in Figure 3, the pin boot 31 has an elastic cover 310 integrated with the coil spring 321. The helical folds formed on the side surface 311 are aligned with the direction in which the wire of the coil spring 321 is wound.

[0013] As shown in Figure 3, in the cross-sectional view of the pin boot 31, the side surface 311 of the elastic cover 310 has alternating folds P and valleys V arranged in the axial direction of the pin boot 31. The coil spring 321 is positioned radially inward from the bottom of the valleys V of the elastic cover 310 and is integrated with the bottom of the valleys V by insert molding. The folds P and valleys V of the elastic cover 310 are connected in a spiral along the direction in which the wire of the coil spring 321 is wound.

[0014] The braking device 1 shown in Figure 1, when applying braking force to the vehicle's wheels, pumps pressurized oil into the cylinder portion 11, pressing the piston 40 against the inner pad 50. The caliper body 10 moves relative to the caliper mount 20 due to the reaction force of the piston 40 pressing against the inner pad 50. The cylinder portion 11 moves inward relative to the caliper mount 20, and the claw portion 12 moves toward the caliper mount 20 and contacts the outer pad 51. The pin boot 31 elastically deforms and stretches in accordance with the relative movement of the cylinder portion 11 relative to the caliper mount 20. The coil spring 321 stretches, and the pitch of the valley portion V of the elastic cover 310 increases.

[0015] Because the valley V of the elastic cover 310 and the coil spring 321 are integrated, the diameter from the central axis of the pin boot 31 to the valley V of the elastic cover 310 does not change easily. On the other hand, as the pitch of the peaks P of the elastic cover 310 widens, the peaks of the peaks P move closer to the bottom of the valley V. Because the coil spring 321 does not easily deform in the radial direction, when the pin boot 31 is stretched, the valley V of the elastic cover 310 does not easily change in the radial direction. Therefore, the slide pin 30 can be suitably supported even while the pin boot 31 is stretched in the axial direction. As a result, the central axis of the slide pin 30 is less likely to deviate from the axial direction of the disc rotor R, and contact of the tip of the slide pin 30 with the caliper mount 20 can be reduced.

[0016] When reducing and releasing the hydraulic pressure in the cylinder portion 11, the caliper body 10 of the braking device 1 relatively moves with respect to the caliper mount 20 by the force of the pin boot 31 trying to return to its natural length from the elastically deformed state. The cylinder portion 11 moves toward the outer side relative to the caliper mount 20, and the claw portion 12 moves in a direction away from the caliper mount 20. As a result, the cylinder portion 11 returns to the original position before pressurization, and the claw portion 12 separates from the outer pad 51.

[0017] It is difficult to obtain a force for relatively moving the caliper body 10 with respect to the caliper mount 20 only by the elastic force of the elastic cover 310. In a case where the runout of the rotating disc rotor R during rotation is used to move the claw portion 12 in the direction away from the caliper mount 20 by the disc rotor R contacting the outer pad 51, thereby moving the cylinder portion 11 toward the outer side relative to the caliper mount 20, drag torque will continue even after pressure release. Since the pin boot 31 of the present disclosure includes the coil spring 321, the position of the caliper body 10 relative to the caliper mount 20 can be restored without the disc rotor R contacting the outer pad 51. Therefore, in the braking device 1, drag torque after pressure release can be reduced.

[0018] [Summary] A braking device according to one aspect of the present disclosure comprises: a caliper body including a cylinder portion that slidably accommodates a piston, a claw portion disposed opposite the cylinder portion via a rotating body that rotates together with a wheel, and a bridge portion that connects the cylinder portion and the claw portion across the rotating body; and a caliper mount to which the other end of a slide pin, one end of which is connected to the caliper body, is connected, and which slidably supports the caliper body along the slide pin in the axial direction of the rotating body. The braking device further comprises a pin boot having a cylindrical shape, with the slide pin inserted therethrough, and the pin boot includes a coil spring and an elastic cover covering the coil spring. According to the present disclosure, since the coil spring of the pin boot is covered by the elastic cover, the waterproof performance of the slide pin inserted into the pin boot and the peripheral portion of the slide pin is improved. Accordingly, the occurrence of rust can be suitably reduced for the slide pin and the peripheral portion of the slide pin.

[0019] In the braking device according to one aspect of the present disclosure, in the above aspect, the pin boot moves the cylinder portion closer to the rotating body and moves the claw portion away from the rotating body by a force tending to return the pin boot to its natural length. In a pin boot that does not include a coil spring, it is difficult to move the cylinder portion closer to the rotating body and move the claw portion away from the rotating body by the force tending to return the pin boot to its original shape from an elastically deformed state. According to the present disclosure, since the pin boot is provided with the coil spring, the cylinder portion can be moved closer to the rotating body and the claw portion can be moved away from the rotating body by the force tending to return the pin boot to its natural length. It is difficult to obtain a force for relatively moving the caliper body relative to the caliper mount only by the elastic force of the elastic cover. Conventionally, utilizing the runout of the rotating body during rotation, the rotating body contacts the outer pad to move the claw portion in a direction away from the caliper mount, thereby moving the cylinder portion toward the outer side relative to the caliper mount. For this reason, drag torque continues to be generated even after pressure release. The pin boot of the present disclosure includes the coil spring, and the position of the caliper body relative to the caliper mount can be restored by the force tending to return the pin boot to its original shape from an elastically deformed state, so drag torque after pressure release can be reduced.

[0020] In the braking device according to one aspect of the present disclosure, in the above aspect, the elastic cover has a plurality of peak portions and a plurality of valley portions that are alternately arranged in an axial cross section, the plurality of peak portions and the plurality of valley portions are continuously connected in a spiral shape along the winding direction of the wire of the coil spring, and the coil spring is disposed radially inward of the bottoms of the plurality of valley portions and is integrated with the bottoms of the plurality of valley portions. Coil springs are often more difficult to change radially than elastic covers. By positioning the coil spring radially inward from the bottom of the spirally connected valley and integrating it, the valley of the elastic cover remains less likely to change radially even when the pin boot stretches. Because the valley of the elastic cover is less likely to change radially, even when the pin boot stretches axially, the axial displacement of the slide pin can be continuously suppressed. As a result of continuously suppressing the axial displacement of the slide pin, it is possible to prevent the tip of the slide pin from contacting the caliper mount.

[0021] [Additional Notes] This disclosure is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of this disclosure. [Explanation of Symbols]

[0022] 1 Braking device 10 Caliper Body 11 Cylinder section 12. Claw part 13 Bridge section 20 Caliper Mount 30 slide pins 31 Pin Boots 40 pistons 310 Elastic Cover 321 Coil spring R Disc rotor (rotating body)

Claims

1. A caliper body having a cylinder portion that slidably houses a piston, a claw portion that is positioned opposite the cylinder portion via a rotating body that rotates with the wheel, and a bridge portion that spans the rotating body and connects the cylinder portion and the claw portion, A braking device comprising a caliper mount to which the other end of a slide pin, one end of which is connected to the caliper body, is connected, and which supports the caliper body so as to be slidable in the axial direction of the rotating body along the slide pin, It has a cylindrical shape and is equipped with a pin boot through which the slide pin is inserted, The pin boot is a braking device having a coil spring and an elastic cover that covers the coil spring.

2. The braking device according to claim 1, wherein the pin boot, by a force that tries to return to its natural length, brings the cylinder portion closer to the rotating body and moves the claw portion away from the rotating body.

3. The elastic cover has a plurality of peaks and a plurality of valleys arranged alternately in an axial cross-section. The aforementioned multiple peaks and multiple valleys are connected in a spiral shape along the direction in which the wire of the coil spring is wound. The braking device according to claim 1, wherein the coil spring is positioned radially inward from the bottom of the plurality of valleys and is integrated with the bottom of the plurality of valleys.

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