JPS6238032Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of the sliding part support structure of a pin type disc brake.

In general, pin type disc brakes include a support fixed to the edge of the rotor and a pad pressing mechanism such as a hydraulic cylinder device that is arranged to straddle the rotor and built into the leg on one side of the rotor. It is equipped with a caliper that has the ability to move in the axial direction of the rotor, and a pair of opposing friction pads that are pressed against the rotor by the caliper, and that the caliper has the ability to slide in the axial direction of the rotor. Since the sliding support part configured to obtain the flexibility can be constructed by sliding a slide pin fixed to one side of the support or caliper and an opening formed in the other, the structure of sealing the sliding part from the outside air is similar to that of the boot. It is known to have the feature of being relatively easy to assemble.

Looking at the sliding support part of such a pin type disc brake from another point of view, it is common to have a pair of left and right pin slide mechanisms to support the caliper, so these pair of left and right slide pins, It is necessary to take into consideration irregularities in the parallelism of the apertures, pitch errors, etc. Therefore, a rubber bushing is often interposed on the sliding surface of the slide pin and the aperture.

In response to recent demands for weight reduction of vehicle-mounted devices or structural simplification, many types of slide pins are fixed to the support side in a cantilevered manner. The opening of the caliper that is slid onto the free end side of the slide pin that is to be attached is shaped like a bag with one end open and the other end closed, or the boot and bushing are integrated to form a similar bag shape. is often used.

By the way, this type of pin type disc brake sometimes causes the following problems. That is, as shown in Figure 1 A and B, boots 1
Fix the rear end to the opening edge of the caliper boss 2,
Normally, the assembly work is performed by inserting the slide pin 3 from the open end on the tip side, but in this case, the open tip of the boot usually has a predetermined tightening margin with respect to the shaft of the slide pin 3. Therefore, the inside of the opening 4 is already sealed from outside air during assembly, which may cause a pressure increase in the air inside. This internal pressurized air acts as a relative movement force between the slide pin 3 and the caliper in the rotor axial direction, causing the caliper's resting position to be distorted during non-braking, and for a certain period of time after assembly. This results in the problem of the friction pad dragging (until the pressure is gradually released from the seal).

Therefore, from these various viewpoints, the present invention has developed a boot assembly structure for the sliding support part of a pin slide type disc brake that does not cause an increase in internal air pressure during assembly by changing the shape of the slide pin. We intend to provide
Specifically, the present invention is characterized by either a support fixed to the edge of the rotor or a caliper arranged to straddle the edge of the rotor and press a pair of opposing friction pads against the rotor. The caliper is slidably supported in the rotor axial direction by sliding a slide pin fixed to one side in a cantilever manner and an opening formed in either the support or the caliper, and the slide pin is provided at the edge of the opening. In the pin type disc brake provided with a sealing member that airtightly engages with the outer periphery of the pin, a boot is provided that extends between the edge of the opening and the circumferential groove provided on the slide pin to seal the sliding portion from outside air. Additionally, the slide pin is formed with a groove that is open in the circumferential groove and extends toward the free end of the slide pin, and the length of the groove in the axial direction of the slide pin is equal to the width of the circumferential groove. The size of the sealing member is substantially equal to that of the sealing member, and is slightly longer than the axial dimension of the sealing member.

Hereinafter, an embodiment of the present invention will be described based on FIG. 2. In the figure, reference numeral 11 is a slide pin fixed to a support (not shown), one end of which is supported by the support, and the slide pin extends in the axial direction of the rotor. It is formed in a certain way. Reference numeral 12 denotes a circumferential groove into which a swollen end portion of a boot to be described later fits.

Reference numeral 13 denotes a caliper boss portion which is inserted and slid together from the free end side of the slide pin 11, and the rear side of this opening 14 is closed, so that the opening 14 has a bag shape. Such a slide pin 11 and opening 1
4, a caliper that is disposed to straddle the edge of the rotor and clamps a pair of friction pads (not shown) against the rotor is supported so as to be movable in the axial direction of the rotor. In order to stably support the caliper, it is necessary to provide a pair of such pin sliding mechanisms on both the left and right sides of the caliper, but it is not necessary that the sliding mechanisms on both sides have the same shape.
The other may simply have a structure that prevents the caliper from rotating. Furthermore, the fixation and formation of the slide pin and the opening may be reversed for the support and caliper.

A sealing member 15 is fixed to the opening edge of the caliper boss 13, and is attached to the outer periphery of the slide pin 11 to seal the sliding surface.

Reference numeral 16 denotes a boot, one of which has a swollen end fixed to the outer body of the opening edge of the caliper boss 13, and the other swollen end is inserted into the circumferential groove 12 while being tightened to a predetermined position on the outer periphery of the shaft of the slide pin 11. Fitted and fixed.

The feature of this example is that in the pin sliding mechanism having such a configuration, a generatrix direction concave groove 1 of a constant length is formed from the circumferential groove 12 of the slide pin 11 toward the free end side.
7, 17... are formed, and the other (distal end side) swollen end 16a of the boot fits into the circumferential groove 12 of the slide pin 11 by such grooves 17, 17... In the previous step, the pressurized air within the boot 16, that is, within the opening 14, was allowed to escape to the outside.

That is, according to such a configuration, when the boot is assembled, the pressurized air in the opening 14 is automatically released to the outside, which eliminates the problem caused by the pressurized air in the sealed opening as in the conventional case. This eliminates the problem of dragging hot friction pads.

Further, the groove 1 in the generatrix direction of the slide pin 11 is
As shown by the symbols A, B, and C in FIG.
A slight gap BC is formed between the area AB and the relative sliding area between the slide pin 11 and the caliper 13, which are located on the free end side of the slide pin, to prevent seal leakage after assembly. There is a need.

Furthermore, since there is usually a slight gap between the slide pin and the opening, the air in the opening at the tip end of the slide pin 11 is vented through the gap during the above-mentioned work. However, in order to make this even better, it is preferable to provide the slide pin with a groove in the generatrix direction that spans the above-mentioned gap and the inside of the boot to vent air during the above-mentioned operation. Therefore, for these reasons, the length of the groove in the generatrix direction provided in the slide pin in the slide pin axial direction is approximately equal to the width dimension of the circumferential groove and slightly longer than the axial dimension of the sealing member. The configuration is preferably adopted.

According to the above configuration, even when assembling the pin type disc brake, there is no risk of pressurized air being generated inside the sealing member in the boot or the opening, and there is no possibility that it will have an adverse effect on the sliding properties of the caliper. Therefore, its practical benefits are extremely large.

It should be noted that the present invention is not limited to the above-mentioned embodiment, and for example, the slide pin may have one generatrix direction groove 17 instead of a plurality of grooves 17.

[Brief explanation of the drawing]

FIGS. 1A and 1B are diagrams for explaining a conventional boot assembly structure for a sliding support section, and FIG. 2 is a diagram for explaining a boot assembly structure for a sliding support section according to the present invention. 1: Boot, 2: Caliper Boss, 3: Slide Pin, 4: Opening, 11: Slide Pin, 12: Circumferential Groove, 13: Caliper Boss, 14: Opening, 15: Seal Member, 16: Boot, 16a: Expansion End, 1
7: Concave groove.

Claims (1)

[Scope of utility model registration request] a support fixed to the edge of the rotor; and a slide pin fixed in a cantilevered manner to either one of the calipers arranged to straddle the edge of the rotor and press the pair of opposing friction pads against the rotor; The caliper is slidably supported in the rotor axial direction through sliding engagement with an opening formed in either the support or the caliper, and a seal member is provided at the edge of the opening to airtightly engage the outer periphery of the slide pin. In the pin type disc brake, a boot is installed between the edge of the opening and the circumferential groove provided in the slide pin to seal the sliding portion from the outside air, and the slide pin has a boot provided in the circumferential groove. A recessed groove is formed that is open and extends toward the free end side of the slide pin, and the length of the recessed groove in the axial direction of the slide pin is approximately equal to the width dimension of the circumferential groove and the axial dimension of the sealing member. The sliding support structure of a pin type disc brake is characterized by being slightly longer than the previous model.