JP2001050317A - Squeal stopping shim for disc brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve suppressing effect for squeal and persistence thereof in a squeal stopping shim for a disc brake. SOLUTION: Reed pieces 8 having free ends partitioned by slits 7 are provided in a part to receive pressurizing force exerted by a pad pressurizing member of a shim 1 such that force of constraint works on the reed pieces 8 at the time of braking. Since the shim 1 can follow the pad by deformation of the reed pieces 8 even when the reed pieces 8 are constrained, the pad is stably received by a torque receiving part and squeal is thereby efficiently suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shim used for countermeasures against squealing of a disk brake, and more particularly to a squealing shim having an improved squeal suppressing effect and an improved durability.

[0002]

2. Description of the Related Art As the prior art of the squealing shim, there is, for example, one disclosed in Japanese Utility Model Publication No. 56-26108 and Japanese Utility Model Publication No. 6-11377.

[0003] The shim of the former publication has a notched shim that changes the coupling rigidity between a brake piston and a friction pad (hereinafter simply referred to as a pad) and a shim without a notch, and lubricating oil is interposed between them. Coated.

Further, in the shim of the latter publication, an inner shim provided with a slit of a cutout hole and an outer shim are overlapped with each other, a lubricant is applied to a laminating interface between the both shims, and a lubricant is stored in the slit of the inner shim. From there, lubricant is supplied to the lamination interface. Further, the inner shim is supported by the outer shim so as to have a degree of freedom of relative movement, and the inner shim is slid to enhance the effect of suppressing squeal.

[0005]

The above-described conventional overlapping shim exhibits its original function while lubrication between the shim and the shim and the back plate of the pad is maintained. However, the effect of suppressing squeal is reduced when lubricity is reduced due to long-term use, deterioration of the lubricant due to rainwater, heat or the like, and reduction in the amount.

[0006] Further, in the conventional overlapping shim, the inner shim is pinched tightly during braking and becomes difficult to move, so that the effect of suppressing the squeal may be insufficient even while the lubricity is maintained.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a squeal shim which exhibits an excellent squeal suppressing effect and which maintains the effect for a long period of time.

[0008]

In order to solve the above-mentioned problems, according to the present invention, a slit is provided in a shim, and a tongue having a free end defined by the slit is provided at a portion receiving a pressing force by a pad pressing member. Form pieces.

The present invention can be applied to both a single-plate shim and a lapping shim. For the lapping shim, the above-mentioned tongue piece is provided on the inner shim having a degree of freedom of movement.

The slit defining the tongue may be either a slit whose one end is open to the outer periphery of the shim or a slit which surrounds the tongue and is open at both ends.

Since the main movement direction of the pad during braking is the rotation direction of the disk (disk rotor), the direction in which the tongue piece extends in the radial direction of the disk is more effective in forming the tongue piece. However, the present invention is not limited to this, and the direction may be arbitrarily determined. Tongue pieces having different directions can be combined to form the same shim.

It is preferable that the tongue is easily deformed.
A tongue piece having a small width is easily deformed. However, a tongue piece having a certain width and increased rigidity is also easily deformed when a root portion is provided with an indented portion for reducing the width.

[0013]

The pad tends to move to a position where it comes into contact with the torque receiving portion during braking. At this time, if the shim follows the pad and moves smoothly, the movement of the pad is not restricted, and the pad is stably pressed against the torque receiving portion, so that vibrations that cause squealing hardly occur.

The shim of the present invention has a tongue piece which is easily deformed at a portion receiving the pressing force of the pad pressing member, and the tongue piece is deformed at the time of braking so that the shim can easily follow the pad. Even if the tongue is tightly restrained, if the tongue deforms, the shim leaves the tongue behind and moves with a small force,
Follow the pads smoothly. By this operation, the pad is less likely to be restrained at an unstable position, and squeal is effectively suppressed.

Further, the shim provided with the tongue piece has excellent vibration damping ability as compared with a shim without the tongue piece because the tongue piece moves in a complicated manner, which also effectively works to suppress the squeal. I suspect that.

As described above, since the shim of the present invention enhances the followability of the shim to the pad by utilizing the deformation of the tongue piece, the effect of suppressing the squeal can be obtained even without the lubricant, and the effect can be maintained. Also excellent in nature.

When a tongue piece is provided on the inner shim for superposition, durability of the shim can be secured by protecting the inner shim having low rigidity with the outer shim. Further, when the present invention is applied to a superimposed shim in which a lubricant is applied to a lamination interface, the effect of the conventional superimposed shim is exerted, and squealing is further reduced.

When the slit for the tongue piece section provided in the inner shim of the superimposed shim is a slit of a cutout hole, the slit can be used as a lubricant reservoir and the durability of the inner shim is secured to some extent. , A more preferable shim can be provided.

[0019]

1 to 6 show an embodiment of a shim according to the present invention.

The shim 1 shown in FIG. 1 has a large number of slits 7 in the radial direction of the disk, one end of which is open to the inner peripheral side, at a predetermined interval, and a large number of tongue pieces 8 extending toward the center of the disk between the slits 7. Is formed.

In the shim 2 shown in FIG. 2, the forming direction of the tongue piece 8 is shown in FIG.
The shim 3 shown in FIG. 3 has a tongue piece 8 extending downward toward the center of the disk (a downwardly extending tongue in the center of the figure) and a tongue piece extending toward the outer peripheral side of the disk (see FIG. 3). The shim 4 in FIG. 4 is formed with a tongue piece 8 extending in the disk tangential direction from the center side to both sides.

The shim 5 shown in FIG. 5 has a cutout hole slit 9 to form a tongue piece 8, and the shim 6 shown in FIG.
Has a slit 10 of a cut-out hole of approximately 1/4 circle, and an arc-shaped tongue 8 is formed in a region pressed by the brake piston.

The shim 4 shown in FIG. 4 and the shim 6 shown in FIG. 6 are provided with a slack portion 11 at the base of the tongue piece 8 for reducing the width of the base. This relief portion 11 helps to facilitate deformation of a tongue piece having a certain width.

FIG. 7 shows a use state of the shim of FIG. As shown, the shim 1 is interposed between the brake piston 21 and the inner pad 22 and between the outer portion 20a of the caliper 20 and the outer pad 23, respectively.

In the drawing, reference numeral 24 denotes a pad pin, 25 denotes a disk, and the pads 22, 23 and the shim 1 pass through the pad pin 24 through a pin hole (12 in FIG. 1 is a pin hole of the shim) and slightly move in the disk rotation direction. It is suspended to have a degree of freedom.

The dashed line in FIG.
2 shows a pressing area by. Most of the tongue 8 in this area is deformable, so that even when the tongue 8 is tightly restrained, the shim 1 can deform the tongue 8 to follow the pad.

The shims in FIGS. 2 to 6 also have similar reasons.
Even when the followability to the pad is improved and the lubrication of the interface is insufficient, the effect of suppressing the squeal is produced.

In the shim 4 of FIG. 4, the tongue 8 extends in the tangential direction of the disk, but the pad tends to move in the direction of rotation of the disk (in the direction of the arrow in FIG. 4) during braking. The desired effect can also be obtained with the tongue piece.

Although the shim 6 in FIG. 6 is used only at the side where the brake piston is located, other shims are effective when used for either the inner or the outer. FIG.
A dotted line indicates an area pressed by the outer claw 21b of the caliper.

FIG. 8 is an example of use of a two-ply shim to which the present invention is applied. The exemplary brakes include pads 22, 23
Is a floating type disc brake of a type in which the torque is supported by a torque member (not shown). The two-layered shim 13 shown in the figure includes an outer shim 14 and an inner shim 15. Outer shim 14 is pad 2
2 (23) has an arm 14a to be held by the back plate. The inner shim 15 is inserted between the outer shim 14 and the back plate of the pad. Here, the shim 5 of FIG. In the shim 5 shown in FIG. 5, a slit 9 which is open at both ends and defines a tongue piece 8 can be used as a lubricant reservoir. The inner shim 15 is stopped by locking a claw 15a provided on one surface side to the outer shim 14. In addition, in a state where the claw 15a is locked, the outer shim 14 has a degree of freedom of relative movement within an appropriate range.

As described above, the forming direction of the tongue piece 8 is not particularly limited.

The material of the shim is preferably stainless steel, but is not limited thereto. In particular, when the tongue piece of the present invention is provided on a shim whose rubber is coated on the surface where the shim is difficult to move, the effect of suppressing the noise is large.

Next, a conventional double-layered shim having a grease reservoir in the inner shim (a shim having a structure shown in Japanese Utility Model Publication No. 6-11377) and the inner shim were replaced with a shim with a tongue piece having the structure shown in FIG. The occurrence frequency of squeal per 1 km of traveling was examined for the double-layered shim of the present invention.

As a result, the conventional product was approximately two times at 10,000 km and approximately five times at 50,000 km, while the product of the present invention was approximately one hundred thousand times at 70,000 km. It was about 2 times at km and it was confirmed that the present invention was extremely effective in improving the effect of suppressing squeal and maintaining the effect.

[0035]

As described above, the shim of the present invention is:
Since the tongue piece which is easily deformed is formed to be restrained at the time of braking, the followability of the shim to the pad at the time of braking is improved, and squeal can be suppressed even if lubricity deteriorates.

Also, the effect of suppressing squeal is exerted for a long period of time, so that it is possible to reduce maintenance work.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a shim of the present invention.

FIG. 2 is a front view of another embodiment.

FIG. 3 is a front view of another embodiment.

FIG. 4 is a front view of another embodiment.

FIG. 5 is a front view of another embodiment.

FIG. 6 is a front view of another embodiment.

FIG. 7 is a sectional view showing an example of use.

8A is a cross-sectional view illustrating an example of use of a two-layered shim, and FIG.

[Explanation of symbols]

 1-6 Shim 7, 9, 10 Slit 8 Tongue piece 11 Loose section 12 Pin hole 13 Two-ply shim 14 Outer shim 14a Arm 15 Inner shim 15a Claw 20 Caliper 21 Brake piston 22, 23 Pad 24 Pad pin 25 Disk

Claims (2)

[Claims] 1. A tongue having a free end defined by a slit in a portion receiving a pressing force by a pad pressing member in a disc brake squealing shim interposed between a back plate of a friction pad and a pad pressing member. A disc brake squeal shim characterized by forming a piece. 2. A lapping shim for disc brakes interposed between a back plate of a friction pad and a pad pressing member by superposing two or more shims and pressing the pad pressing member via an outer shim. A tongue having a free end defined by a slit is formed in a portion of the inner shim to receive a pressing force of the inner shim.