JPS6221788Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a caliper device for a disc brake that has an adjusting mechanism in the cylinder.

[Prior art]

This type of disc brake device is capable of hydraulic operation from the master cylinder and mechanical operation using mechanical force from a handbrake, etc., and its adjust mechanism adjusts according to the displacement of the piston. A hydraulic chamber is defined in the cylinder by the cylinder and the piston so as to perform
This piston is engaged with a braking member that is movable in the axial direction and whose rotation is regulated to regulate the rotation of the piston, and an adjustment bolt and a nut member screwed therein are connected to the hydraulic pressure chamber. The nut member engages with the piston to restrict its rotation and is biased toward the front side of the cylinder within the piston by the first spring, while the adjuster bolt is rotatable toward the cylinder and has a built-in adjuster. The adjusting bolt is biased toward the rear of the cylinder, and the rear end of the cylinder engages in a clutch with the large diameter end of a sleeve piston having a large diameter portion and a small diameter portion. The end of the small diameter part of the sleeve piston is in contact with a rod that is operated by mechanical operation, but in the disc brake caliper device having the above structure, the head of the adjustment bolt is attached to the large diameter part of the sleeve piston during assembly work. However, it was difficult to evacuate the air between the two, making assembly difficult.

[Purpose of invention]

The present invention was developed in view of the above points, and aims to improve the assembly performance of the adjuster bolt, so that the automatic braking gap adjustment device operates properly, and the shape of the push rod that is operated by mechanical operation is simple. The purpose of the present invention is to provide a disc brake caliper device that is easy to manufacture.

[Structure of the idea]

In order to achieve the above object, the present invention provides an atmospheric pressure chamber on the head end face of the adjusting bolt, and an atmospheric communication hole is bored between the large diameter end of the sleeve piston and the push rod fitting recess at the other end. A push rod for transmitting a mechanical operating force is brought into contact with a fitting recess of the sleeve piston to close the atmosphere communication hole.

〔Example〕

Next, an embodiment of a disc brake caliper device according to the present invention will be described with reference to the drawings.

The caliper 1 consists of an actuating part 1a, a counter-actuating part 1b, and a bridge part 1c connecting these parts.The caliper 1 straddles the disk 2 by the bridge part 1c, and is provided on a bracket 3 so as to be movable in the disk axial direction. A cylinder 4 that is open on the disk 2 side is formed in the actuating portion 1a, and a pot-shaped piston 5 is slidably fitted in a liquid-tight manner into the large diameter portion 4a of the cylinder 4 by means of a piston seal 6. As a result, a hydraulic chamber 7 is defined within the cylinder 4, and the hydraulic chamber 7
A liquid passage hole 8 is provided inside. Friction pads 9 and 9', which are braking members, are arranged on both sides of the disc 2. The friction pad 9 on the cylinder side is supported by the bracket 3 so as to be movable in the disc axial direction, but its rotation is restricted. The friction pad 9' engages with the counteracting part 1b.

The head 5a of the piston 5 is formed with recesses 5b at a suitable number of locations, and the recesses 5b are fitted into corresponding recesses 9b formed in the back plate 9a of the friction pad 9. 5a is in contact with the back plate 9a. As a result, the piston 5 pushes the friction pad 9 in the disk axial direction, but its rotation is restricted by the friction pad 9.

An adjuster 12 consisting of an adjuster bolt 10 and an adjuster nut 11 is built in the hydraulic chamber 7, and the adjuster nut 11 has a multi-thread internal thread 11a.
A multi-thread male screw 10a is formed in each of the small-diameter shaft portions of 0, and both 11a and 10a are screwed together with a multi-thread screw with a small screwing gap.

The adjustment nut 11 is engaged with the piston 5 with a press-fit pin 11c press-fitted into the head 11b fitted into an air vent groove 5e provided at the bottom 5d of the piston 5 to restrict rotation.

Further, the head 10b of the adjusting bolt 10 is provided with a communication hole 10d for supplying the hydraulic oil in the hydraulic pressure chamber 7 to the tapered clutch portion 10c, and the tip of the adjusting bolt 10 is sealed by a cup seal 10e as described below. Large diameter portion 13a of sleeve piston 13
It is fluid-tightly and rotatably fitted inside. Further, an atmospheric pressure chamber 10f is recessed in the end face of the head 10b of the adjusting bolt 10.

Reference numeral 13 denotes a sleeve piston, and the sleeve piston 13 is arranged so that its large diameter part 13a is located in the hydraulic pressure chamber 7 of the cylinder 4, and its small diameter part 13b is located in the small diameter part 4b of the cylinder 4. 4. The pin 13c implanted on the rear end side is fitted into the locking hole 4d drilled in the rear end bottom 4c of the large diameter portion 4a of the cylinder 4, so that the cylinder 4 can move in the axial direction while being restricted from rotating. It is provided.

Further, the large diameter portion 13a of the sleeve piston 13
The head 10 of the adjusting bolt 10 is attached to the end face of the adjusting bolt 10.
There is provided a hollow cylindrical portion 13d into which the clutch holder b is fitted, and a tapered clutch surface 13e is formed at the opening edge of the hollow cylindrical portion 13d.

One end of the first spring 14 wound around the shaft of the adjusting nut 11 is attached to the head 11b of the adjusting nut 11, and the other end is attached to the spring receiver stopper 15 fitted in the annular groove 5g on the inner periphery of the cylindrical portion 5f of the piston 5. The adjusting nut 11 is urged toward the piston, and the front surface of the head 11b is in contact with the inner surface of the piston 5. An air exhaust groove 17, which is deeper than the annular groove 5g, is formed on the inner surface of the cylindrical portion 5f of the piston 5 so as to straddle the annular groove 5g in the axial direction of the piston. This makes it easier to discharge.

A brewer hole 19 is opened in the hydraulic pressure chamber 7, and a circumferential groove 20 is provided across the brewer hole 19 on the inner peripheral surface of the large diameter portion 4a of the cylinder 4. A retainer 22 is provided by locking a proximal end flange portion 22 a to a ring-shaped retainer stopper 21 .
The cylinder 4 is biased toward the rear by a conical second spring 18 whose large-diameter end is locked to the cylinder 2b and whose small-diameter end abuts against the head 10b via a bearing 23. .

The small diameter portion 13b of the sleeve piston 13 is surrounded by a seal ring 24, and is fitted in the cylinder small diameter portion 4b in a fluid-tight and slidable manner.

A cylindrical rear wall 1d is formed on the side opposite to the hydraulic pressure chamber of the cylinder small diameter part 4b, and is integrally connected to the actuating part 1a so as to be perpendicular to the cylinder small diameter part 4b and communicate with the cylinder small diameter part 4b. , a camshaft 25 has a bearing 26 on the inner surface of this rear wall 1d.
It is rotatably inserted through the intervening .

The conical recess 27 formed in the end face of the small diameter portion 13b of the sleeve piston 13 and the camshaft 2
A push rod 29 is interposed between the cam groove 28 and the cam groove 28 formed in the axial direction of the push rod 5. This push rod 29 has both ends formed into a spherical shape, and is pushed by the rotation of the camshaft 25 to push the sleeve piston 13 in the braking direction.

Furthermore, an atmospheric communication hole 13f communicating with the hollow cylindrical portion 13d of the large diameter portion 13a is bored at the innermost part of the conical recess 27 of the sleeve piston 13 into which one end of the push rod 29 is fitted. The conical recess 27 side of the atmosphere communication hole 13f is closed by the working end of the push rod 29 to prevent dust from entering.

A lever 30 is fixed to the camshaft 25 by a nut 31, and when the lever 30 is rotated in the direction A in FIG.
5 rotates counterclockwise in FIG. 3, the brake is applied, and when the brake is released, the return spring 32 rotates in the direction B and returns to the initial position.

In addition, 33 is a sliding pin, which is attached to the arm portion 1e of the caliper 1.
The caliper 1 is attached by a mounting bolt 33a to support the caliper 1 in a slidable manner.

Next, the operation of this embodiment will be explained.

When the pressure fluid from the master cylinder is introduced into the hydraulic chamber 7 through the fluid passage hole 8, the piston 5 moves to the left in FIG. As a result, the caliper 1 moves in the opposite direction to the right, and the reaction part 1b presses the other friction pad 9' toward the other side of the disk 2, thereby producing a braking action.

At this time, as the piston 5 moves forward, the adjusting nut 11 also moves forward together with the first spring 14, but the amount of movement of the adjusting nut 1
1 multi-thread female screw 11a and adjustment bolt 10
This is the amount of backlash that fills the gap between the threaded male screw 10a and the multi-thread male screw 10a, and since no axial force is generated that acts on the threaded portion of the multi-thread screw, no rotational torque is generated, and therefore the adjuster bolt 10 rotates. The braking action is carried out without any friction.

When the friction pads 9, 9' are worn out and the braking gap becomes larger than the set value, when a braking action is performed, the amount of movement of the piston 5 is determined by the gap between the adjustment nut 11 and the adjustment bolt 10 in which the multi-thread screw is engaged. When the amount of backlash exceeds , the adjusting bolt 11 and adjusting nut 10 move forward together, and the head of the adjusting bolt 10 attempts to separate from the large diameter portion 13b of the sleeve piston 13, and at this time, the sleeve piston 13 communicates with the atmosphere. Hole 1
Atmospheric air is introduced from 3f, and they are smoothly separated, and an axial force is applied to the multi-thread threaded part due to the hydraulic pressure in the hydraulic chamber 7. This axial force causes the adjuster bolt 10 to rotate, and the adjuster 12 to rotate. The clutch portion 10c of the adjuster bolt 10 re-engages with the clutch surface 13e of the large diameter portion 13a of the sleeve piston 13, stopping rotation and achieving automatic adjustment of the braking gap. When the adjusting bolt 10 is extended, the head 10b of the adjusting bolt 10 fits into the hollow cylindrical portion 13d of the sleeve piston 13.
b and the bottom of the sleeve piston 13 is compressed into the atmospheric pressure chamber 10e recessed in the end face of the head 10b of the adjusting bolt 10 and gradually removed from the atmospheric communication hole 13f. is carried out smoothly. When the adjuster 12 expands, the clutch portion 10c of the adjuster bolt 10 rotates and slides into contact with the clutch surface 13e of the large diameter portion 13a of the sleeve piston 13. Since the diameter of the clutch surface is large, a large frictional resistance is obtained. Instantly stop the rotation of the adjustment bolt 10,
To reliably prevent over-adjustment. Then, when the supply of pressure fluid is stopped and the master cylinder piston (not shown) returns due to the action of the return spring, the hydraulic pressure in the hydraulic pressure chamber 7 of the cylinder 4 decreases, and the piston 5 returns to its original state due to the piston seal 6. Although it tries to return to the position, it is restricted by the extended adjuster 12, and the disk 2 and friction pads 9, 9'
The braking gap between the two is automatically adjusted to remain constant.

Next, the handbrake action will be explained.

When you pull the handbrake lever (not shown),
The lever 30 receives this mechanical force and rotates in the direction A in FIG. 4. As a result, the camshaft 25 rotates counterclockwise in FIG.
The rod 29 is pushed to the left, whereby the piston 5 is pushed by the adjuster 12 via the sleeve piston 13 and moves forward to the left, pressing one friction pad 9 to one side of the disk 2. This reaction causes the caliper 1 to move in the opposite direction to the right, pressing the other friction pad 9' against the other side of the disk 2 and applying the handbrake.

At this time, one spherical end of the push rod 29 pushes the sleeve piston 13 toward the adjuster bolt 10.
When pressed against the head 10b of the sleeve piston 13, the clutch surface 13e of the sleeve piston 13 and the adjuster bolt 10
Since the frictional resistance between the clutch portions 10c increases, the adjusting bolt 10 does not rotate. Therefore, the state of the multi-thread screw engagement between the nut member 11 and the adjuster bolt 10 does not change, and the adjuster 12 can perform braking by mechanical operation without shrinking.

[Effect of idea]

As described above, the present invention has an atmospheric pressure chamber recessed in the head end face of the adjusting bolt, an atmospheric communication hole bored between the large diameter end of the sleeve piston and the push rod fitting recess at the other end, and Since the push rod that transmits the operating force is in contact with the fitting recess of the sleeve piston, it is possible to bleed air when fitting the adjusting bolt head to the sleeve piston, making assembly work easier, and reducing hydraulic pressure. When the braking gap is automatically adjusted during operation, when the head of the adjuster bolt separates from the hollow cylindrical part of the sleeve piston, air is introduced from the atmosphere communication hole, and the adjuster extends and the head of the adjuster bolt becomes hollow. When re-entering the cylindrical part, the atmospheric pressure chamber becomes a compression space and air can be gradually released from the atmospheric communication hole, allowing smooth movement of the adjustment bolt and automatic adjustment of the appropriate braking gap. In addition, even if foreign matter should enter the cylinder from the camshaft side, the atmospheric communication hole is closed by the working end of the push rod, preventing it from entering the hollow cylindrical portion of the sleeve piston and the hydraulic pressure chamber. In addition, the push rod transmits the mechanical operating force, and since it is sufficient to simply close the air communication hole, it is possible to use a straight member with both ends formed into spherical shapes, and has the advantage of being easy to process.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a plan view, Fig. 2 is a front view, Fig. 3 is a cross-sectional view of Fig. 1, and Fig. 4 is a side view of the camshaft mounting part. be. 1 is the caliper, 4 is the cylinder, 5 is the piston,
7 is a hydraulic pressure chamber, 9 and 9' are friction pads, 10 is an adjustment bolt, 10f is an atmospheric pressure chamber, 11 is an adjustment nut, 13 is a sleeve piston, 13f is an atmosphere communication hole, 14 is a first spring, and 18 is a first spring. 2
19 is a spring, 22 is a retainer, 24 is a camshaft, 28 is a cam groove, 29 is a push rod, and 30 is a lever.

Claims (1)

[Scope of utility model registration request] In the hydraulic pressure chamber defined by the actuation piston fitted in the cylinder of the actuating part of the caliper, there are an adjustment nut and an adjustment bolt fitted with a multi-thread screw of the automatic braking gap adjustment device, and a sleeve that transmits the mechanical actuation force. A large diameter portion of the piston is disposed, the adjusting nut is biased in the braking direction by a spring, and the adjusting bolt is inserted between the head of the adjusting bolt and a retainer whose base end is fixed to the inner periphery of the hydraulic pressure chamber. The sleeve piston is biased in the anti-braking direction by the contracted spring, and the sleeve piston has a large diameter portion that engages with the inner periphery of the hydraulic pressure chamber to restrict rotation and is movable, and has an opening in the hydraulic pressure chamber. A braking action is performed by the pressure fluid supplied from the fluid passage hole, and the other end of the sleeve piston is brought into contact with the working end of a push rod operated by mechanical operation, and the sleeve piston is pressed by the operation of the push rod. In a caliper device for a disc brake that performs braking by pushing the operating piston through the braking gap automatic adjustment device, an atmospheric pressure chamber is provided at the head end face of the adjustment bolt, and the large diameter end of the sleeve piston is provided with an atmospheric pressure chamber at the head end face of the adjustment bolt. An atmosphere communication hole is formed between the push rod fitting recess at the other end, and a push rod for transmitting mechanical operating force is brought into contact with the fitting recess of the sleeve piston to close the atmosphere communication hole. Disc brake caliper device.