JPH03194225A - Floating type disk brake - Google Patents

Abstract

PURPOSE:To prevent an outer pad from uneven wear even if a caliper swings in braking by making the rigidity of an outer claw of the caliper at the disk turning-in side larger than that at the disk turning-out side. CONSTITUTION:An outer claw 6 of a caliper 1 has the rigidity of the disk turning-in side claw 6a larger than that of the disk turning-out side claw 6b so that the wall thickness is ta>tb. The outer claw 6 tends to be opened axially of the disk from the root side start point in braking, while the rigidity of the claw at the disk turning-in side is larger than that at the disk turning-out side, so that the opening amount at the turning-in side is smaller than that at the turning-out side and surface pressure at the disk turning-in side is larger than that at the disk turning-out side when the caliper 1 is assumed to generate no swing. Thus, the surface pressure difference generated in an outer pad by the swing is offset by the surface pressure difference due to the opening amount of the claw to prevent the outer pad from uneven wear.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a floating disc brake for braking a vehicle that has an enhanced effect of preventing uneven wear of a friction band.

[Conventional technology]

As shown in FIGS. 2 to 4, a floating type disc brake supports a caliper 1 that straddles a disc rotor D by providing a sliding part 3 between it and a torque member 2 so that it can slide in the disc axial direction. The brake piston 5 has one friction band 4 inserted into the inner side of the caliper 1, with the rotor D disposed facing each other and supported so as to be slidable in the disk axial direction, and the other pad 4' is slid by reaction force on the outer side of the caliper. Each is pressed with a claw 6 so as to be brought into sliding contact with the disk surface.

By the way, in this type of disc brake, the pressing surface of the brake piston and the pressing surface of the caliper outer pawl are made symmetrical on the disk insertion side and the rotation side with respect to the center of the pad.

However, because the caliper swings as shown by the chain line in FIG. 1 during braking due to the clearance created in the slide portion 3 (the swing state is exaggerated in the figure), uneven wear of the band occurs in the above-described structure. That is, due to changes in the surface pressure distribution due to the swing, the inner pad 4 wears out faster on the disk rotation side, and the outer pad 4' wears out faster on the disk rotation side.

Therefore, as a countermeasure against this uneven wear, the center of the piston is biased toward the disk rotation side from the band center, or the piston is arranged in two positions so that the piston area on the rotation side is larger than the piston area on the rotation side. things are being done.

[Problem to be solved by the invention]

The above-mentioned measures include, in a multi-pot type disc brake having two brake pistons, making the center between the pistons biased toward the disc rotation side from the pad center. However, although these measures are effective in suppressing uneven wear of the inner pad, they are less effective for the outer pad because they do not restrict the swing of the caliper itself.

[Means to solve the problem]

In this invention, in order to effectively prevent uneven wear of the outer pad, the rigidity of the outer pawl of the caliper is made greater on the disk insertion side than on the disk rotation side.

Note that this configuration is suitable for disc brakes in which two brake pistons are provided shifted in the rotational direction of the disc, and the area of the piston on the disc rotation side is greater than or equal to the area of the piston on the disc rotation side. center or 2
It is more effective to use this method in a disc brake in which the center of the pistons is biased from the center of the pad toward the disc rotation side.

[Effect]

The outer pawl of the caliper tries to open in the disc axial direction starting from the base side during braking, but the rigidity of the pawl is greater than that on the disc rotation side or the rotation side, so the amount of opening on the rotation side is smaller than on the rotation side. Therefore, assuming that no swing occurs in the caliper, the surface pressure will be greater on either the disk retraction side or the disk retraction side.

Therefore, the difference in surface pressure that occurs on the outer pad due to the swing of the caliper (large on the rotation side) is offset by the difference in surface pressure caused by the amount of opening of the pawls (large on the rotation side), and this averages out the surface pressure distribution, causing the outer pad to uneven wear is prevented.

Incidentally, since the uneven surface pressure distribution is also a cause of so-called squealing, the present invention is also effective in suppressing squealing.

〔Example〕

FIG. 1 shows an embodiment of the present invention, in which the outer pawl 6 of the caliper 1 has the rigidity of the pawl 6a on the disk insertion side greater than the rigidity of the pawl 6b on the disk extraction side. Its wall thickness is 1s>1. It's true. This difference in wall thickness can be created by machining, but if it is created when the caliper is cast, no machining is required to create the difference in rigidity.

Note that methods for making the rigidity of the claw 6a greater than that of the claw 6b include providing reinforcing ribs or built-up parts on the claw 6a, or
It is also conceivable that a high-rigidity member be buried in the a.

〔effect〕

As described above, in this invention, the rigidity of the outer pawl of the caliper on the disc retraction side is made greater than that on the disc retraction side, so even if the caliper swings during braking, uneven wear of the outer pad is effectively prevented. can be prevented,
Moreover, there is an effect that the effect of suppressing squeals can be enhanced at the same time.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an embodiment of the present invention in a partially broken state, Fig. 2 is a plan view showing an example of a conventional floating type disc brake, and Fig. 3 is an end view of the inner side thereof. , FIG. 4 is an end view of the outer side. 1... Caliper, 2... Torque member, 3... Slide part, 4.4'
...Friction bar throat, 5...Brake piston, 6...Outer claw, 6a...Disc rotation side claw, 6b...・
・Claw on the disc rotation side, D... Disc rotor.

Claims (3)

[Claims] (1) A caliper that straddles the disc rotor is supported so that it can slide in the disc axial direction, and one of the friction pads that are arranged facing each other with the disc rotor in between is inserted into the inner side of the caliper, and the other is inserted into the inner side of the caliper, and the other is inserted into the outer side of the caliper. A floating type disc brake in which each of the pawls is pressed and brought into sliding contact with a disc surface, characterized in that the outer pawls of the caliper have greater rigidity on the disk rotation side than on the disk rotation side. (2) Claim (1) wherein two of the brake pistons are provided with their positions shifted in the rotational direction of the disc, and the area of the piston on the disc retraction side is greater than or equal to the area of the piston on the disc retraction side.
) Disc brakes as described. (3) The disc brake according to claim (1) or (2), wherein the brake piston is provided biased toward the disc rotation side.