JP2010031960A - Anti-squeal shim and disc brake using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-squeal shim for a disc brake which is effective for general squeals as well as squeals at specific frequency. <P>SOLUTION: By forming a rotor rotation-in side 3 and a rotor rotation-out side 4 of the anti-squeal shim 1 with different materials, the shim rigidity of the rotor rotation-in side 3 is improved compared with the shim rigidity of the rotor rotation-out side 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a squeal prevention shim employed in a disc brake for a vehicle and a disc brake using the squeal prevention shim to enhance the squeal prevention effect during braking.

  As a technique to suppress so-called squealing (abnormal noise such as squeal noise) during braking, which is a problem with disc brakes, a brake piston (hereinafter simply referred to as a pad) and a brake piston that presses the pad and makes sliding contact with the disc rotor Alternatively, a squeal prevention shim is interposed between the outer claws of the calipers.

  This squeal prevention shim includes a single-sheet type and a structure in which a plurality of sheets (two mainstream) are stacked. The latter squeal prevention shim is disclosed in, for example, Patent Document 1 below. In the squeal prevention shim disclosed in the same document, the two inner and outer component plates are overlapped, and the two component plates are integrally coupled with a coupling piece provided to correspond to both. Some plates are integrated by bonding with an adhesive.

  This squeal prevention shim suppresses squeal by damaging the pad's vibration by placing soft material such as rubber with a cushioning function on the entire surface for squealing at a specific frequency such as squealing. The method to do is used a lot.

JP 2004-328771 A

  The squeal prevention shim used in vehicle disc brakes is expected to be able to handle a wide range of squeal. Although effective against the noise, the vibration damping performance of the soft material is uniform in each part of the shim, so it cannot cope with the squeak due to complicated phenomenon, and it cannot be expected to suppress the squeal in general. . For this reason, squeal may occur depending on the type of brake and braking conditions, and the structure must be improved.

  For example, in a floating disc brake, the caliper swings during braking, so the inner side pad has a surface pressure on the rotor entry side, and the outer side pad has a surface pressure on the rotor exit side. Such disc brakes have a tendency to become high, and in particular, it is difficult to deal with a wide range and the squeal is not sufficiently suppressed.

  It is an object of the present invention to realize and provide a squeal prevention shim that is effective not only for squealing at a specific frequency but also for general squealing, and a disc brake that uses the squeal suppression effect to enhance the squeal suppression effect. It is said.

  In order to solve the above-described problems, in the present invention, the rigidity of the squeal prevention shim at the rotor turn-in side portion is different from the rigidity at the rotor turn-out side portion. Specifically, the shim rigidity of the rotor outlet side portion was made higher than the shim rigidity of the rotor outlet side portion. Note that the rotor turn-in side portion and the rotor turn-out side portion referred to in the present invention are based on the time of forward movement of the vehicle in which the disk rotor rotates normally.

  In this squeal prevention shim, the rotor feed-in side part and the rotor feed-out side part are formed of different materials, so that the shim rigidity of the rotor feed-in side part can be made higher than the shim rigidity of the rotor feed-out side part.

  Further, a shim is constituted by a main part formed of a rigid material and a buffer material layer covering at least a part of the surface of the main part, and the thickness of the main part on the rotor inlet side is set on the rotor outlet side. The same object can be achieved by making the thickness thicker than the thickness.

  As for the latter structure, a form in which the entire region of the surface of the main part is covered with the buffer material layer and a form in which only the surface of the main part on the rotor delivery side is covered with the buffer material layer can be considered. The shock-absorbing material layer may be a rubber coating layer that has been used in the past, and by utilizing this shock-absorbing material layer, the thickness of each part of the shim is compensated to compensate for the difference in thickness between the main rotor inlet side and rotor outlet side. Can be made uniform.

  The present invention also provides a disc brake in which the above-described squeal prevention shim of the present invention is interposed between a brake pad and a brake piston or an outer claw of a caliper.

  A conventional anti-squeal shim that uses a soft material (buffer material) to dampen pad vibration reduces the restraining force that suppresses the amplitude of the pad due to the use of the soft material. It seems that it was the cause of making it. For example, for a noise having a frequency of 2000 to 3000 Hz, a shim without a rubber coating layer is more effective than a shim having a buffer rubber coating layer on the surface.

  The inventor considered that the vibration damping performance of the pad by the cushioning material could be brought out while suppressing the decrease in the force of restraining the pad by making a difference in the rigidity of each part of the shim. And it discovered that the demand could be met by making the shim rigidity of the rotor delivery side part higher than the shim rigidity of the rotor delivery side part. The input energy of the pad on the rotor inlet side is larger than that on the rotor outlet side. By increasing the rigidity of the shim on the rotor inlet side, the pad is effectively restrained even in the floating disc brake. This was confirmed and the present invention was completed.

  1 to 5 show an embodiment of a squeal preventing shim according to the present invention. FIG. 1 shows an example of the overall shape of a squeal prevention shim. In this squeal prevention shim 1, the shim rigidity of the rotor feed-in side part 3 is higher than the shim rigidity of the rotor feed-out side part 4. The overall shape is approximated to the contour shape of the back plate of the pad, and a plurality of locking claws 2 for holding the back plate of the pad are provided on the periphery.

  The locking claw 2 is not an essential element. The shim can be supported by providing an engaging portion to the mount. Further, in a disc brake that supports a pad by inserting a pad pin into a through hole provided in the back plate of the pad, the squeal prevention shim 1 can be supported by being suspended with the pad pin together with the pad. The locking claw 2 may not be provided.

  Specific measures for making the shim rigidity of the rotor feed-in side portion higher than the shim stiffness of the rotor feed-out side portion are shown in FIGS. In the squeal prevention shim 1 of FIG. 2, the rotor turn-in side portion 3 and the rotor turn-out side portion 4 are formed of different materials, and both are integrally connected via a mechanical connection portion 5. The rotor turn-in side portion 3 is formed of SPCC (cold rolled steel plate or steel strip), SUS (stainless steel plate), or the like. The rotor delivery side portion 4 is formed of a rubber or soft resin plate material, or a material in which the surface of the steel plate is covered with a rubber or soft resin layer (including an adhesive layer). The rigidity of the entrance side part 3 is higher than the rigidity of the rotor exit side part 4.

  The squeal prevention shim 1 of FIG. 2 combined with different materials adopts a specially shaped connecting portion 5 having a mutual entry portion in the rotor radial direction as shown in FIG. If the structure is such that the relative movement of the delivery side portion 4 in the direction of rotation of the disk rotor is prevented, it is easy to handle and the reliability of preventing dropout during use is enhanced.

  The squeal prevention shim 1 shown in FIG. 3 includes a plate-like main portion 6 made of a rigid material such as stainless steel, and a cushioning material layer 7 made of rubber, soft resin, or the like. The main portion 6 has a rotor feed-in side 6a thicker than a rotor feed-out side 6b. Therefore, the shim rigidity of the rotor feed-in side portion 3 is greater than the shim stiffness of the rotor feed-out side portion 4. Is also high. The buffer material layer 7 is provided over the entire area of both surfaces of the main portion 6, but the thickness of the main portion 6 on the rotor outlet side 6 b is larger than the thickness on the rotor inlet side 6 a. The difference compensates for the difference in thickness between the rotor inlet side and the rotor outlet side of the main portion 6 so that the thickness of the shim is uniform throughout.

  The squeal prevention shim 1 of FIG. 4 also includes a plate-like main portion 6 made of a rigid material such as stainless steel, and a buffer material layer 7 made of rubber, soft resin, or the like. The buffer material layer 7 is provided only on the surface of the main portion 6 on the rotor delivery side 6b. Although this point is different from the shim of FIG. 3, the thickness of the rotor feed-in side 6a of the main part 6 is thicker than the thickness of the rotor feed-out side 6b as in the shim of FIG. The shim rigidity of the side part 3 is higher than the shim rigidity of the rotor delivery side part 4. The buffer material layer 7 is provided so that the thickness of the shim is uniform throughout.

  In addition, as shown in FIG. 5, the thickness difference between the rotor inlet and outlet sides of the main part 6 may be a thin plate made of a highly rigid material (a plate made of the same material as the main part). ) May be bonded by welding or the like to increase the thickness of the portion.

  When the squeal prevention shim 1 of the present invention configured as described above is adopted for a disc brake, a decrease in pad restraining force on the rotor entry side is suppressed, while a vibration damping effect by the buffer material layer 7 is also exhibited and is extensive. It becomes possible to respond to squeal.

  Next, an example of the disc brake of the present invention is shown in FIGS. The illustrated disc brake is a floating type. The floating type disc brake 10 includes a caliper 11, pads (brake pads) 12 and 12, which are opposed to each other with a disc rotor D interposed therebetween, a mount 13 that also serves as a torque member, a brake piston 14, and a rotor turn-in side. And a slide guide portion 15 that slidably supports the caliper 11 in the axial direction of the rotor on both the rotor delivery side and a squeal prevention shim 1 that characterizes the present invention.

  The caliper 11 has an inner portion 11a, an outer claw 11b, and a bridge portion 11c that integrally connects both of them across the outer periphery of the disc rotor D, and the brake piston 14 is inserted into a cylinder 16 provided on the inner portion 11a. Has been. The brake piston 14 presses the pad 12 on the inner side to make sliding contact with the disk rotor D. Further, the caliper 11 slides toward the inner side by the reaction force at this time, and the outer claw 11b presses the pad 12 on the outer side to make sliding contact with the disk rotor D. The outer periphery of the brake piston 14 is liquid-tightly sealed by a piston seal 17.

  The above configuration is the same as the conventional product. This between the brake piston 14 and the inner pad 12, and between the caliper outer claw 11b and the outer pad 12, the shim rigidity on the rotor entry side is made higher than the shim rigidity on the rotor delivery side. The squeal prevention shim 1 of the present invention is interposed, and for this reason, the pad 12 is stably restrained on the rotor entrance side, and it is possible to deal with squeal due to complicated phenomena.

  The squeal prevention shim of the present invention was prototyped, and the trial shim and a conventional shim coated with a rubber coating layer were adopted for the floating disc brake to compare the squeal suppression effect. As a result, it was confirmed that the shim of the present invention can cope with the general phenomenon of squealing.

  The present invention can be expected to have a particularly great effect when applied to a floating disc brake in which caliper behavior is difficult to stabilize during braking. However, the present invention is also effective when applied to a piston-facing disc brake.

The perspective view which shows the outline | summary of an example of the squeal prevention shim of this invention The front view which shows the detail of an example of the squeal prevention shim of this invention Sectional drawing which shows the detail of the other example of the squeal prevention shim of this invention Sectional drawing which shows the detail of the further another example of the squeal prevention shim of this invention Sectional drawing which shows the detail of the further another example of the squeal prevention shim of this invention The top view which shows an example of the floating type disc brake which employ | adopted the squeal prevention shim of this invention Sectional drawing along the XX line of FIG. Sectional drawing along the YY line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Squeaking prevention shim 2 Locking claw 3 Rotor return side part 4 Rotor return side part 5 Connection part 6 Main part 6a Rotor return side 6b Rotor return side 7 Cushioning material layer 10 Floating disc brake 11 Caliper 11a Inner part 11b Outer claw 11c Bridge part 12 Pad (brake pad)
13 Mount 14 Brake piston 15 Slide guide portion 16 Cylinder 17 Piston seal D Disk rotor

Claims (4)

  A squeal prevention shim interposed between a brake pad (12) of a disc brake and a brake piston (14) that presses the brake pad (12) to make sliding contact with the disc rotor (D) or an outer claw (11b) of a caliper A squeal prevention shim characterized in that the shim rigidity of the rotor outlet side portion (3) is higher than the shim rigidity of the rotor outlet side portion (4).   The rotor feed-in side part (3) and the rotor feed-out side part (4) are formed of different materials so that the shim rigidity of the rotor feed-in side part (3) is higher than the shim rigidity of the rotor feed-out side part (4). The squeal prevention shim according to claim 1, wherein the squeal prevention shim is high.   A shim is constituted by a main portion (6) formed of a rigid material and a cushioning material layer (7) covering the entire surface of the main portion (6) or the surface on the rotor delivery side, and the main portion The thickness of the rotor inlet side (6a) of (6) is made thicker than the thickness of the rotor outlet side (6b), and the shim rigidity of the rotor inlet side portion (3) is changed to the shim of the rotor outlet side portion (4). The squeal prevention shim according to claim 1, wherein the squeal prevention shim is higher than rigidity.   A brake piston (14) or a caliper that presses the brake pad (12) and its brake pad (12) to slidably contact the disc rotor (D) with the squeal prevention shim (1) according to any one of claims 1 to 3. Disc brake interposed between the outer claws (11b) of the disc.

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