JPH0842608A - Pad clip with pad returning mechanism - Google Patents

Abstract

PURPOSE:To reduce the number of part items and the number of man hour by facing the tip of a returning spring part of a pad clip to the disc rotor surface so as to form a wear indicator part. CONSTITUTION:A wear indicator part 63 is formed by bending each returning spring part 58, which energizes friction pads 26, 28 in the direction for separating from a disc rotor 24, from a clip main body, and extending it to the front side of a pad back plate 70 so as to contact with the edge of the back plate 70 so as to give the pad returning force, and facing the tip to the disc rotor 24. A separate wear indicator member is thereby eliminated, and the number of part items is reduced. Shape of the friction pads 26, 28 is simplified so as to reduce the number of man hours. Piston stroke of a piston at the time of braking can be normally maintained and the brake delay can be prevented by setting the spring constant of the returning spring parts 58 smaller than the spring constant of a piston seal of a hydraulic cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a pad clip mounted between an end surface of a pad and a support for preventing abrasion of a friction pad, returning the pad to a non-braking position and a clearance between the pad rotor and the disk rotor. The present invention relates to a pad clip with a pad returning mechanism having a function of forming a pad and a wear indicator function capable of detecting wear of the pad to a certain thickness.

[0002]

2. Description of the Related Art In a disc brake, a hydraulic cylinder provided in a caliper presses inner and outer pads disposed on both sides of the disc rotor against both sides of the disc rotor to perform a braking action. When the braking operation is released, the pad is separated from the disc rotor to form a predetermined clearance between the two in order to prevent the pad from rubbing. A wear indicator is also attached to the friction pad to inform the driver that the pad has worn out and needs to be replaced. Further, conventionally, the pad returning mechanism and the wear indicator are generally constituted by different members.

As a conventional mechanism for returning a friction pad to a non-braking position, an inverted V-shaped spring 1 is attached to a caliper, and the tip of the spring is engaged with each of the upper edges of a pair of friction pads. A structure in which a pair of friction pads are operated so as to be pushed open by the elastic force of a V-shaped spring is generally used.

On the other hand, as a conventional wear indicator mounting structure, as shown in Japanese Utility Model Publication No. 61-12423, the base end of the wear indicator is caulked and fixed to the rear surface of the friction pad, and the tip of the wear indicator is fixed. There is one in which the side of the pad backing is bent by bending the side to cross the backing of the pad and projecting to the front side of the backing of the pad. To this end, FIG.
As shown in FIG. 5, the wear indicator is caulked and attached to the caulking portion 14 provided on the front surface of the backing metal 12 of the friction pad 10, or as shown in FIG. Then, this insertion recess 1
A wear indicator is inserted and fixed to the item 6.

[0005]

However, in the structure for attaching the wear indicator to the pad back metal described above, a caulking portion is formed on the back metal to caulk and fix the wear indicator, or a concave portion is formed on the back metal to attach the wear indicator. Since it is necessary to insert and fix it, not only the number of parts is increased, but also the shape of the pad is complicated, the number of processing steps is increased, and the cost is increased.

On the other hand, in the conventional pad returning mechanism using the V-shaped spring, as shown by reference numeral 18 in FIG.
2, it is necessary to process the insertion hole for inserting the end of the V-shaped spring, and the processing of the pad is troublesome. In the friction pad returning mechanism using the V-shaped spring, the piston of the hydraulic cylinder provided in the pad and the caliper may be returned more than necessary at the time of releasing the braking, and the piston stroke at the time of braking becomes long and the braking delay is delayed. Cause to occur.

The present invention has been made to solve the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a pad clip with a pad returning mechanism which can reduce the number of parts and the number of processing steps. Another object of the present invention is to provide a pad clip with a pad returning mechanism that can prevent the friction pad and the piston from returning more than necessary.

[0008]

To achieve the above object, a pad clip with a pad returning mechanism according to the present invention is a friction pad which is brought into pressure contact with a disk rotor by a piston fitted in a hydraulic cylinder provided in a caliper. When,
In a pad clip with a pad returning mechanism, a pad spring mounted on a support for supporting a braking force from the friction pad is provided with a return spring portion for urging the friction pad in a direction to separate the friction pad from the disc rotor. ,
The return spring portion is bent from the clip body and extends to the front side of the pad backing metal, and the tip portion is bent toward the pad backing metal side to contact the edge of the backing metal to provide a pad returning force, and the tip end is the disk rotor. It has a structure as a wear indicator part by facing to. The spring constant of the return spring portion may be set smaller than the spring constant of the piston seal of the hydraulic cylinder.

[0009]

According to the present invention constructed as described above, since the tip of the return spring portion of the pad clip faces the disk rotor surface to form the wear indicator portion, a separate wear indicator member is not required and the number of parts can be reduced. It is possible to reduce. Moreover, in the present invention, it is not necessary to form a caulking portion for crimping the wear indicator on the pad backing metal, or to form an insertion recess for inserting and attaching the wear indicator, which simplifies the shape of the pad. Therefore, the number of steps can be reduced and the cost can be reduced. Also, by making the spring constant of the return spring part smaller than the spring constant of the piston seal of the hydraulic cylinder, it is possible to prevent the friction pad and the piston of the hydraulic cylinder from being returned more than necessary, and the stroke of the piston during braking is reduced. It can be maintained normally and braking delay can be prevented.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a pad clip with a pad returning mechanism according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 3 is a plan view of a disc brake equipped with a pad clip with a pad returning mechanism according to an embodiment of the present invention.

In FIG. 3, the disc brake 20 is
A support 22 fixed to a vehicle body (not shown) is formed so as to straddle the disc rotor 24. This support 22
Is a pair of friction pads 2 composed of an inner side and an outer side.
6 and 28 are slidably guided in the axial direction of the disc rotor 24, and a braking force is generated by receiving a braking torque from the friction pads 26 and 28. Further, the disc brake 20 has a caliper 30 for pressing the friction pads 26, 28 against the disc rotor 24, and the caliper 30 has a floating structure attached to the support 22 via the guide portion 32. There is. The inner portion of the caliper 30 is provided with a hydraulic cylinder mechanism 34, which pressurizes the inner pad 26 toward the rotor surface, and the reaction force moves the caliper 30 to the inner side, so that the caliper 30 Of the outer pad 2 by a pair of caliper claws 36, 36 (see FIG. 4) extending to the outer side of the
Similarly, 8 is pressed and moved toward the rotor surface to perform the braking action. Then, the anchor convex portions 38 formed by projecting to the left and right ends of the friction pads 26 and 28, and the protrusions 38 are fitted therein to form an anchor surface that supports the braking force from the friction pads 26 and 28. A pad clip 42 having a pad returning mechanism for the friction pads 26 and 28 is disposed between the pad 22 and the anchor recess 40.

That is, the pad clip 42 includes a portion fitted to the pad convex portion 38 and a portion fitted to the anchor concave portion 40, and is attached to the support 22 side so as to face the pad outer end surface. As shown in FIG. 5, the inner clip body 44 and the outer clip body 46, which are mounted on the inner side and the outer side respectively, are formed by a plate material that is connected and integrated by a connecting plate 48.

Each clip body 44, 46 is formed following the shape of the support 22 that faces the outer end surfaces of the friction pads 26, 28. In particular, a crank bent portion 50 along the anchor recess 40 is formed in the middle thereof. Here, the braking force transmitted through the convex portion 38 of the friction pad is transmitted to the support 22 side. Also, both clip bodies 44, 4
Inner edge part of crank bending part 50 in 6 (rotor side)
An inner pressing claw 52 is formed on the inner surface of the clip body 4 by abuttingly engaging the inner surfaces of the support inner and the outer.
4, 46 are prevented from coming off the rotor surface from the anchor surface. Further, a sandwiching piece 54 is provided on the outer edge portion of the crank bending portion 50 so as to be in contact with the outer surface of the support anchor portion corresponding to the inner pressing claw 52. The sandwiching piece 54 is bent into an S-shape and is given elasticity, whereby the support anchor recess 40 is sandwiched and held from the inner and outer surfaces, and the pad clip 42 is fixedly held by the support 22. ing. Therefore, the S-shaped sandwiching piece 54 can secure the tightening margin for the support 22.

A pad returning mechanism 56 is integrally formed on the outer edge portions of both clip bodies 44 and 46 of the pad clip 42 which can be mounted and held on the support 22 in this manner. The pad return mechanism 56 includes a return spring portion 58 continuous with the S-shaped sandwiching piece 54 described above,
The frictional pads 26, 28 are in contact with the front surfaces (rotor side surfaces) of the frictional pads 26, 28 and urge the pads 26, 28 away from the disk rotor 24 in a returning direction.

The return spring portion 58 includes the S-shaped holding piece 54.
It is formed by a strip plate continuous with, and is curved so as to follow the elliptical shape. That is, about four-half circumferences of the ellipse are the S-shaped sandwiching pieces 54, and the other portions are curved so as to follow the ellipse, and the extended tip end thereof is crank-bent of the clip bodies 44, 46. It has been extended to 50 parts. Then, the extension end of the return spring portion 58 is
The return force imparting portion 62 is bent toward the friction pads 26 and 28 and bent into an S-shape, and the back side of the return force imparting portion 62 contacts the pad anchor convex portion 38, as will be described later. A return force is applied to the friction pads 26, 28, and the tip of the friction pads 26, 28 serves as a wear indicator portion 63 facing the disc rotor 24.

That is, the return spring portion 58, which is connected to the tip of the S-shaped sandwiching piece 54 provided on the outer edge of the crank bending portion 50, is connected to the sandwiching contact P (sandwiching) by the S-shaped sandwiching piece 54. The elastic force is applied so as to expand the equivalent diameter of the curved ellipse with the portion (where the piece 54 contacts the outer surface of the support 22) as a base point. Then, the tip of the return spring portion 58 is extended to the front edge side of the pad backing metal 70 as shown in FIG.
The back surface of the S-shaped returning force applying portion 62 formed at the tip of 8 contacts the front surface of the pad backing metal 70 to apply a returning force to the pad backing metal 70 in the direction of separating the friction pads 26, 28 from the disc rotor 24. ing. Also, the return spring portion 5
The returning force of the pad 8 against the pad is set to be smaller than the sliding resistance between the piston (not shown) and the piston seal of the hydraulic cylinder mechanism 34 provided in the caliper 30.
The returning force applied by the returning force applying portion 62 to the friction pads 26, 28 via the pad backing 70 becomes larger than necessary,
The friction pads 26 and 28 and the piston of the cylinder mechanism 34 are returned more than necessary, and the friction members 71 and 7 of the pads 26 and 28 are returned.
It is intended to prevent a braking delay from occurring due to an increase in the clearance between the disk rotor 3 and the disk rotor. Then, the wear indicator 63 at the tip of the returning force applying portion 62 is set to a predetermined height, and the friction pad 26,
When the friction members 71, 73 of 28 contact the disk rotor 24 when they are worn to a predetermined thickness, a noise is generated by the contact with the rotor to inform the driver of the replacement timing of the friction pads 26, 28. ing.

On the other hand, the pad pushing-up portion 9 is provided on the lower surface of the crank bending portion 50 with which the lower side surface of the anchor convex portion 38 contacts.
2 is formed. The pad pushing-up portion 92 is provided by integrally extending a plate piece 93 on the outer edge portion of the lower surface portion, folding the plate piece 93 upward, and inserting the tip into the crank groove of the crank bending portion 50. . And the plate piece 9
A spring force is applied to the plate piece 93 as the elastic loop portion 94 by looping the folded portion of 3 to push the anchor convex portion 38 of the friction pads 26 and 28 upward, and improve the slidability of the pads 26 and 28. , To prevent rattle noise.

The operation of the embodiment constructed as described above is as follows. FIG. 1 shows a plan sectional view of the state where the pad clip 42 provided with the pad returning mechanism 56 is mounted on the support 22. In this state, the pad anchor convex portion 38 is fitted into the support anchor concave portion 40. Then
Between the both, the crank bending portion 5 of the clip body 44, 46
The pad anchor convex portion 38 rides on the plate piece 92, with 0 interposed therebetween.

During braking, when hydraulic pressure acts on the hydraulic cylinder mechanism 34 provided on the caliper 30, the inner pad 26 slides on the plate piece 93 of the pad pushing-up portion 92 and the arrow 7 in FIG.
6, the friction material 71 is pressed against the inner side surface of the disk rotor 24 by moving in the direction of the rotor axis. Then, the caliper 30 is moved to the inner side by the reaction force, and the friction material 73 of the outer pad 28 is moved to the disc rotor 24.
It is pressed against the outer side of the. At this time, the inner side and outer side return force applying portions 62 formed on the pad clip 42 have already been attached to the friction pad 26,
The pad backing 70 of 28 is contacted with the front surface of the pad
However, since the pressing force of the pad by the piston of the hydraulic cylinder mechanism 22 is larger than the returning force applied to the pad of the returning force applying portion 62, the pad is moved in the rotor axial direction together with the pads 26 and 28. To do. Then, the return spring portion 58 of the pad returning mechanism 56 formed on the inner side and the outer side of the pad clip 42 is elastically deformed so that the ellipse equivalent diameter is reduced, and a larger returning force is accumulated. .

When the hydraulic pressure of the hydraulic cylinder mechanism 34 is released and the braking is released, the returning force applying portion 62 pressing the inner surface of the pad backing metal 70 is returned by the elastic force of the returning spring portion 58. , The pads 26, 28 are returned to their original positions while being pressed in the direction away from the disc rotor 24 as indicated by arrows 78, 79. At this time, the return force of the return spring portion 58 to the pad is set to be smaller than the sliding resistance between the piston (not shown) of the hydraulic cylinder 22 and the piston seal, so that the friction pads 26 and 28 and the piston of the hydraulic cylinder are Without returning more than necessary, the pad is returned to a normal position where the clearance between the pad and the disc rotor 24 reaches a predetermined value. Therefore, it is possible to prevent the stroke of the piston from increasing at the time of the next braking to cause a braking delay.

When such a braking operation is repeated and the friction materials 71 and 73 of the friction pads 26 and 28 are worn out,
That is, for example, when the friction material 71 of the pad 26 is worn to the position of the chain double-dashed line in FIG. 1, the disc rotor 24 causes the tip wear indicator portion 63 of the restoring force applying portion 62 to contact the disc rotor 24. Therefore, the wear indicator portion 63 generates a rubbing noise due to the rotation of the disk rotor 24, and informs the driver that the friction pads 26, 28 have worn to the extent necessary for replacement.

As described above, in the embodiment, since the wear indicator 63 is formed integrally with the pad returning mechanism 56 of the pad clip 42, a separate member is not required as a wear indicator, and the number of parts can be reduced. Can be planned. Moreover, since the wear indicator portion 63 is integrated with the pad clip 42, it is not necessary to form a caulking portion for fixing the wear indicator or an insertion concave portion in the pad backing 70 as in the conventional case, and the shape of the friction pad can be simplified. At the same time, the number of processing steps can be reduced, and the cost can be reduced. Also, the clip body 4
Since the pad pushing-up portion 92 is provided on the lower surface portion of the crank bending portions 50 of Nos. 4 and 46, it is possible to improve the slidability of the friction pads 26 and 28 and suppress the generation of rattle noise.

In the above embodiment, the case where the returning force applying portion 62 is formed in the S shape has been described, but it may be formed in the shape of a crank or may be bent in a state inclined with respect to the surface of the pad backing metal 70. The inclined bent portion is brought into contact with the front side edge portion of the pad backing plate 70 so that the friction pad is caused to exert a component force parallel to the rotor surface and a component force (returning force) orthogonal to the rotor axial direction. May be.

[0024]

As described above, according to the present invention, since the tip of the return spring portion of the pad clip faces the disc rotor surface to form the wear indicator portion, a special wear indicator member is not required. Therefore, the number of parts can be reduced. Moreover, in the present invention, it is not necessary to form a caulking portion for crimping the wear indicator on the pad backing metal, or to form an insertion recess for inserting and attaching the wear indicator,
The shape of the pad can be simplified, the number of steps can be reduced, and the cost can be reduced. Also, by making the spring constant of the return spring part smaller than the spring constant of the piston seal of the hydraulic cylinder, it is possible to prevent the friction pad and the piston of the hydraulic cylinder from being returned more than necessary, and to reduce the stroke of the piston during braking. It can be held normally and braking delay during braking can be prevented.

[Brief description of drawings]

FIG. 1 is a plan sectional view of an essential part of a disc brake equipped with a pad clip according to an embodiment of the present invention.

FIG. 2 is a perspective view of a pad clip according to an embodiment.

FIG. 3 is a plan view of a disc brake equipped with a pad clip according to an embodiment.

FIG. 4 is a view seen from the outer side of the disc brake equipped with the pad clip according to the embodiment.

FIG. 5 is a diagram illustrating a conventional wear indicator attachment structure.

[Explanation of symbols]

 22 Support 24 Disk Rotor 26, 28 Friction Pad 30 Caliper 34 Hydraulic Cylinder Mechanism 42 Pad Clip 56 Pad Return Mechanism 58 Return Spring Part 60 Return Force Applying Part 63 Wear Indicator Part 70 Pad Backing 71, 73 Friction Material

Claims (1)

[Claims] 1. A pad clip mounted between a friction pad pressed against a disk rotor by a piston fitted into a hydraulic cylinder provided in a caliper and a support for supporting a braking force from the friction pad, In a pad clip with a pad return mechanism provided with a return spring portion for urging the friction pad away from the disc rotor, the return spring portion is bent from the clip body and extends toward the front side of the pad backing metal, and the tip portion A pad clip with a pad returning mechanism, characterized in that the pad is bent toward the back metal side of the pad to give a pad returning force by contacting the edge of the back metal, and the tip of the pad is made to face the disk rotor to form a wear indicator portion.