JPS6212406B2 - - Google Patents

Abstract

PURPOSE:To protect a diaphragm from wear and damage by forming a reservoir by stopping up with the diaphragm the opening end of the larger-diametered portion of a stepped through hole which is formed in a caliper and in which a support shaft is fitted slidably. CONSTITUTION:A support shaft 1 is slidably fitted in the smaller-diametered portion 15 of a stepped through hole 15-15' bored in a caliper 3, and is prevented from slipping off in the axial direction by a flange 2 and a plug 5. The plug 5 stops up a cylinder 6 of an oil-pressure generator 4 incorporated in the shaft 1. A diaphragm 17 is fixed in position by the screwing of a cap 19 having an air vent 20, and there is formed a reservoir 22 between the opening end of the larger-diametered portion 15' of the hole 15-15' and the cap 5. Irrespective of the charged oil amount, the diaphragm 17 scarecely contacts other parts and scarecely receives vibrations with great influence mainly in the radial direction of the shaft 1; therefore, the diaphragm 17 can be protected from wear and damage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a small disc brake incorporating a hydraulic generator and a reservoir.

In hydraulically actuated disc brakes, oil leakage leads to brake ineffectiveness, and thus prevention measures have been considered to be an extremely important problem.

This problem is particularly important in motorcycles and other vehicles where the brake system, hydraulic generator, piping, etc. are usually exposed outside the vehicle, and for this reason, the relatively robust brake system caliper and its support itself have a hydraulic power generator reservoir. A small disc brake with built-in hydraulic piping has been developed and offered.

The present invention improves the structure of the reservoir in such a small disc brake, that is, the caliper that straddles the disc holds the disc using hydraulic pressure from a hydraulic pressure generator built into a support shaft that supports the caliper. In a small disc brake of the type that obtains braking force by pressing one of the opposing friction pads against the disc and swinging around the support shaft due to the reaction force, the other friction pad is pressed against the disc, the support shaft has a shaft. A large diameter flange is provided on one end, and a plug that closes the cylinder of the built-in hydraulic pressure generator is fixed on the other end.
The caliper is provided with a stepped through hole, and the support shaft is slidably fitted into the small diameter portion of the caliper, and is assembled so as to be prevented from coming off in the axial direction by the flange and plug, and A small disc brake with a built-in reservoir is characterized in that a diaphragm is assembled to close the open end of a large diameter part of a through hole to form a reservoir within the large diameter part.

The present invention will be explained below based on an embodiment shown in the drawings. In Fig. 1, reference numeral 1 denotes a support shaft fixed to a vehicle body fixing part (not shown), and its axial direction is a tangent to a disk (not shown). parallel to the direction. Reference numeral 2 denotes a large diameter flange formed on the support shaft 1, which serves as an anchor portion that receives torque from the caliper 3 during braking, and a plug 5 that closes the cylinder 6 of the hydraulic generator 4 built into the support shaft 1. At the same time, the caliper 3 is supported swingably and immovably in the axial direction. 7 is a piston that slides into the cylinder 6, and is normally biased by the spring force of a spring 8 so as to come into contact with the plug 5, and the brake cable 9 connected to the other end is pulled in the direction of the arrow in the figure. This causes oil pressure to be generated in the oil chamber 10. 11 is a spring seat, 12 and 13 are cup seals, and 14 is a port for connecting the hydraulic operating mechanism built in the caliper 3 and the oil chamber 10. Through this hydraulic pressure transmission, the hydraulic operating mechanism is connected to the opposite side with the disk in between. One of the friction pads is pressed against the disk, and the caliper 3 is operated to press the other friction pad against the disk due to the rocking caused by the reaction force.

Reference numerals 15 and 15' denote stepped through holes formed in the caliper 3, which are inserted into the support shaft 1 from the open end on the side of the small diameter portion 15 and brought into contact with the flange 2, and the washer 16 that engages with the stepped portion is inserted into the support shaft 1 from the open end on the side of the small diameter portion 15. By fixing the plug 5 to the tip of the support shaft 1 through the
The caliper 3 is prevented from coming off in the axial direction.

Reference numeral 17 denotes a diaphragm assembled to the open end of the large diameter portion 15' of the stepped through hole, and the thick peripheral portion is in the circumferential recess 18 formed at the open end edge of the large diameter portion 15' of the caliper 3. Fitted, air circulation hole 2 in the center
It is fixed by screwing the cap 19 which has a diameter of 0. By assembling this diaphragm 17, the inside of the large diameter portion 15' is isolated from the outside air, and the return port 2
1 to form a reservoir 22.

In the small disc brake configured as described above, the diaphragm 17 forming the reservoir 22
is assembled to the caliper 3, and there is almost no risk of it coming into contact with other parts regardless of the amount of oil filled, and the possible effects of vibration in this type of disc brake are mainly due to the support shaft 1. Since it is large in the radial direction and small in the axial direction, the diaphragm 17 is not damaged by abrasion due to this vibration. Compared to the conventional method in which a substantially cylindrical diaphragm is assembled, the structure is simplified, and the practical benefits are extremely large, such as the excellent prevention effect of the abrasion damage to the diaphragm mentioned above. be.

[Brief explanation of the drawing]

The drawing is a partial plan cross-sectional view of a small disc brake showing an embodiment of the present invention. 1... Support shaft, 2... Flange, 3... Caliper, 4... Hydraulic generator, 5... Plug, 6... Cylinder, 7... Piston, 8... Spring, 9... Brake cable, 10... Oil chamber, 11... Spring seat, 12,
13...Cup seal, 14...Port, 15,1
5'...Stepped through hole, 16...Washer, 17...Diaphragm, 18...Recess, 19...Cap, 20...
Air circulation hole, 21...Return port, 22...Reservoir, 23, 24...Seal ring.

Claims (1)

[Claims] 1 The caliper sitting astride the disc presses one of the opposing friction pads that sandwich the disc against the disc using hydraulic pressure from a hydraulic pressure generator built into the support shaft that supports the caliper, and the reaction force causes movement around the support shaft. In a small disc brake of the type that obtains braking force by pressing the other friction pad against the disc by the rocking of the support shaft, the support shaft is provided with a large diameter flange at one end, and a cylinder of a built-in hydraulic pressure generator at the other end. A stepped through hole is provided in the caliper, and the support shaft is slidably fitted to the small diameter portion of the caliper, and is prevented from coming off in the axial direction by the flange and the plug. A small disc brake with a built-in reservoir, characterized in that a diaphragm is assembled to close the open end of the large diameter part of the stepped through hole to form a reservoir in the large diameter part.