JP2998367B2 - Disc brake caliper retract mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple retracting mechanism having a structure for returning a caliper of a floating disc brake.

[0002]

2. Description of the Related Art As shown in FIG. 5, a general floating disc brake is such that a piston seal 3 fitted on the outer periphery of a brake piston 2 is deformed by a certain amount when the piston advances, and the elastic restoring force of the seal is used. When the pressure is released, the piston is pulled back by a certain amount. If the pads are not separated from the disk when the brake is not applied in this manner, the pads 4 and 5 may be dragged by the disk. However, in this piston retract system, the caliper remains at the braking position even after depressurization, so that the outer side of the caliper Drag prevention of the outer side pad 5 pressed by the nail is insufficient.

[0003] As a countermeasure, Japanese Patent Publication No.
A caliper retract mechanism as disclosed in JP-A-18 is proposed. In this mechanism, as shown in FIGS. 6 and 7, a second sleeve 8 is provided on the slide guide portion 6, and the sleeve slides relative to the slide pin 7. In the structure of FIG. In the structure shown in FIG. 7 in which the sleeve 8 moves integrally with the slide pin 7 between the second sleeve 8 and the second sleeve 8.
The springs 10 are interposed between the calipers, and the caliper is returned by the repulsive force of the springs which is compressed at the time of braking.

[0004]

The above-mentioned conventional caliper retract mechanism requires a space due to the provision of a spring and a sleeve, has a complicated structure and is expensive, and has a reduced caliper return amount due to pad wear. As a result, there is a disadvantage that the braking performance is not stable.

It is an object of the present invention to eliminate such disadvantages.

[0006]

In order to solve the above-mentioned problems, a slide pin fixed to one of the caliper and the fixing member is inserted into a pin hole provided in the other so that the caliper can be slid in the disk axial direction. In the supported floating disc brake, a ring is provided in a holding groove of a slide pin liquid seal formed at an entrance of the pin hole,
This ring is fitted to the outer periphery of the slide pin so as to slide with a certain force or more, and when the ring is braked, the liquid seal is compressed in the moving direction of the caliper and the caliper is released by the restoring force of the liquid seal when the pressure is released. It is configured to return. In addition, before
The inner edge of the ring where the liquid seal is in contact
It is desirable to remove it by processing.

[0007]

When the liquid seal at the inlet of the pin hole is compressed during braking, the caliper returns due to the restoring force of the seal. Therefore, the seal holding groove may be slightly deepened, and a small ring for compressing the seal to be fitted in the slide pin may be provided therein, without increasing the space and complicating the structure.

Further, when the pad wears and a force greater than a certain force is applied to the ring, the ring and the slide pin relatively slide, so that the caliper return amount is always kept substantially constant. Note that the inner peripheral edge on the side where the liquid seal contacts is chamfered.
Then, as shown in FIG.
A space is created between the plug 15 and the liquid seal 14, and FIG.
(B) As shown in FIG.
Since the screw 14 enters, compared to the case without chamfering
As a result, a large amount of caliper tract can be secured.

[0009]

FIG. 1 shows an example of a floating disc brake. The slide guide portions 6 of the caliper 1 are provided at two locations, that is, the inlet side and the outlet side of the disk D, as shown in the figure. In the slide guide portion shown here, one end of a slide pin 7 is screwed to the caliper 1 and the other end of the pin is slidably inserted into a pin hole 9 (see FIG. 2) formed in the torque member 11. The slide pin 7
Moves with caliper 1.

FIG. 2 shows details of the slide guide section of FIG. The slide pin 7 has a rubber boot with an exposed portion.
2 and the inlet of the pin hole 9 is sealed and protected by a liquid seal 14 at the end of the pin boot. As shown in the drawing, the liquid seal 14 is often provided with the holding groove 13 at the entrance of the pin hole and is incorporated therein. Therefore, in the present invention, the liquid seal 14 is used as a caliper return source. To this end, the holding groove 13 is made slightly deeper than in the prior art to create a space between the holding groove 13 and the liquid seal 14, and a ring 15 having a chamfered inner peripheral edge is provided in the space as necessary. Then, the ring 15 made of resin or the like is fitted to the outer periphery of the slide pin 7 so as to obtain a clearance between the torque member 11 and the sliding pin 7 so as to obtain a constant sliding resistance. The outer pad is slightly separated from the disk in the state shown in FIG.

In this manner, during braking, the outer pad hits the disk, and then the caliper 1 moves to the right in the drawing until it is slightly compressed and the compression stops, and at the same time, the ring 15 also moves as shown in FIG. ) To the right together with the slide pin 7. For this reason, the liquid seal 14 is compressed by the ring 15 and deformed as shown in FIG. 3B.
Is pushed back and the caliper returns. The caliper return amount at this time is such that when the pad wears during braking, the movement inhibiting force of the ring 15 by the liquid seal 14 overcomes the sliding resistance between the slide pin and the ring 15 and the ring 15 Since it slips, it almost matches the caliper movement amount during braking. Therefore, the gap secured between the outer pad and the disk after the pressure is released is almost always constant, and the drag on the outer side can be eliminated without causing a change in the pedal stroke.

FIG. 4 shows that the slide pin 7 is connected to the torque member 1.
1 is a type of brake which is fixed to the caliper 1 and inserted into a pin hole 9 provided in the caliper 1. Also in this case, the ring 1 is placed between the liquid seal 14 at the end of the pin boot 12 and the holding groove 13.
When the caliper 1 is provided, the sealing seal 14 is compressed by the relative movement of the caliper 1 and the ring 15 during braking, and the caliper returns when the pressure is released.

It is desirable that the retract mechanism of the present invention configured as described above is provided on both the guide portion on the disc rewind side and the rewind side. However, even if it is provided only on the guide portion on the disc rewind side, the outer pad can be dragged. Effective for prevention.

Since the ring 15 must be larger in diameter than the exit hole of the holding groove 13 in order to prevent the liquid seal 14 from coming off, the ring 15 is recessed as shown in FIG. As the ring 15 to be inserted, a C-shaped ring or a coiled ring is used. After reducing the diameter of the ring and inserting it into the groove 13, the slide pin 7 is attached. As shown in FIG. 4, when the liquid seal 14 is mounted by press-fitting with an integrated retainer or the like, since the holding groove 13 is processed straight, the ring 15 may be a normal ring.

[0015]

As described above, the retract mechanism of the present invention uses the originally required liquid seal to return the caliper, so that the structure can be simplified, the cost can be reduced, and the size can be reduced.

Further, since the change in the caliper return amount due to the wear of the pad is prevented by the relative movement of the ring and the slide pin, deterioration in responsiveness, pedal stroke, pedal feeling, etc. does not occur. Note that the ring
The chamfered edge on the side where the
Liquid seal deformation is larger than without chamfering
Is important for enhancing the effect of preventing dragging.
A large amount of caliper retract at the time of depressurization can be secured.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a floating disc brake.

FIG. 2 is a sectional view showing an example of a caliper retract mechanism used for the brake of FIG. 1;

3A is an enlarged view of a main part of the mechanism of FIG. 2 in a non-braking state, and FIG. 3B is an enlarged view of the same braking state.

FIG. 4 is a diagram showing an example of application to a brake in which a slide pin is fixed to a torque member.

FIG. 5 is a sectional view showing a piston retract mechanism of the floating disc brake.

FIG. 6 is a sectional view showing an example of a conventional caliper retract mechanism.

FIG. 7 is a sectional view showing another example of the conventional caliper retract mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Caliper 2 Brake piston 3 Piston seal 4 Inner pad 5 Outer pad 6 Slide guide part 7 Slide pin 8 Second sleeve 9 Pin hole 10 Spring 11 Torque member 12 Pin boot 13 Seal holding groove 14 Liquid seal 15 Ring D disk

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16D 65/02 F16D 55/224 111 F16D 65/54

Claims (2)

(57) [Claims] In a floating type disc brake in which a slide pin fixed to one of a caliper and a fixing member is inserted into a pin hole provided in the other and the caliper is supported so as to be slidable in a disc axial direction, A ring is provided in the holding groove of the slide pin liquid seal formed at the inlet, and the ring is fitted over the outer periphery of the slide pin so as to slide with a certain force or more. Wherein the caliper is restored by the restoring force of the liquid seal when the caliper is released. 2. The retractable mechanism for a disc brake caliper according to claim 1, wherein an inner peripheral edge of the ring on a side in contact with the liquid seal is chamfered and removed.