JP2595545Y2 - Disc brake with parking - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake provided with a parking brake and, more particularly, to a disc brake with parking which is characterized by its caliper.

[0002]

2. Description of the Related Art Conventionally, as a disk brake provided with a parking brake, for example, Japanese Utility Model Laid-Open No. 1-60038
Some are described in Japanese Patent Publication No. In this case, a cylinder opened to the disk rotor side is formed in the caliper. The cylinder includes a large-diameter portion, a small-diameter portion, and a parking working chamber in this order from the disk rotor side, and a cup-type piston having the closed end wall at the opening end side of the cylinder is liquid-tight and slidable on the large-diameter portion. The hydraulic chamber is movably fitted to define a hydraulic chamber, and an adjuster including a sleeve nut and a spindle screwed to each other is provided coaxially with the piston in the hydraulic chamber. The portion is engaged with a plug that fits slidably and liquid-tightly with the small diameter portion. One end of a connecting rod abuts on the parking operation chamber side of the plug, and the other end of the connecting rod is connected to a rotating cylindrical cam by a parking cable.

The connecting rod and the cam constitute a parking operating member, and the plug is urged toward the parking operating chamber by a return spring disposed in the hydraulic chamber. Then, when the brake pedal is depressed, the master cylinder is activated, and the hydraulic pressure from the master cylinder activates the cup-type piston to press the brake pads against both surfaces of the disk rotor.

When an operating part such as a lever of a parking brake is operated, a cam is rotated via a parking cable, and a plug is pushed to a disk rotor side via a connecting rod to engage with the plug. The cup-shaped piston moves toward the disk rotor via the adjuster, and the brake pad is pressed against the disk rotor.

The above-mentioned parking operation member uses a cam mechanism, but may use a lever mechanism, a screw mechanism, or the like.

[0006]

However, in the above-described disc brake with parking, a caliper body having a built-in hydraulic chamber and a parking working chamber forming portion for guiding a parking working member that operates in conjunction with the parking brake are provided. Are integrally formed, so that the entire caliper needs to be changed according to the on-vehicle requirements of the parking cable in the parking brake which differs depending on the vehicle type.

To change the characteristic value of the caliper in response to the occurrence of abnormal noise such as brake squeal, it is necessary to change the shape of the caliper itself, such as the build-up. Also,
If the caliper main body and the parking working chamber forming portion are integrally formed as described above, it is difficult to correct so-called build-in clearance due to backlash of the screw portion of the adjuster, so that the predetermined movement amount of the cup-type piston is required. An error occurs in the cam rotation angle with respect to, and a lost stroke occurs in the initial operation of the parking lever following the error, leading to a deterioration in the operational feeling.

The present invention has been made in view of the above-mentioned problems, and it is possible to cope with various kinds of parking cables and to change the eigenvalue by simple means. It is an object of the present invention to provide a disc brake with parking that can suppress lost stoke.

[0009]

In order to achieve the above object, a parking brake with parking according to the present invention has a caliper formed with a cylinder which is opened to the disk rotor side, and the cylinders are sequentially increased from the disk rotor side. A hydraulic pressure chamber is defined by a piston having a large diameter portion, a small diameter portion, and a parking working chamber, and a piston having a closed end wall at the opening end side of the cylinder is liquid-tightly and slidably fitted to the large diameter portion. An adjuster comprising two members screwed to each other is disposed coaxially with the piston in the hydraulic chamber, and the small-diameter portion of the adjuster is fitted to the small-diameter portion so as to be liquid-tight and axially movable. Engaging with the mating plug, and further into the parking working chamber,
In a disc brake with a parking provided with a parking operation member for moving the plug in the axial direction by being connected to a parking cable, the parking operation chamber forming portion is formed separately from the caliper main body, and the caliper main body and the In the parking working chamber forming part,
It is characterized in that a spacer is interposed between end faces facing each other in the moving direction of the cup type piston.

At this time, the parking operation chamber forming portion may be assembled to the caliper body by screw fitting.

[0011]

According to the requirements for the parking cable in the parking brake, which differs depending on the vehicle type, only the parking operation chamber forming portion for guiding the parking operation member is changed without changing the caliper main body incorporating the brake cylinder device main body. This addresses the various on-vehicle requirements.

At this time, the parking working chamber forming portion is
Since it is not involved in the formation of the hydraulic chamber of the cylinder, it is not necessary to make the portion to be assembled with the caliper body liquid-tight, and the assembly is simplified. Therefore, the parking operation chamber forming portion can be displaceably attached to the caliper body in the moving direction of the piston by screw fitting, spline fitting, or the like, and can be detachably attached.

[0013] The play of the stroke from the set value of the piston when the parking brake is actuated due to the backlash of the meshing portion between the members constituting the adjuster is interposed by a spacer having a predetermined thickness. Absorption prevents an initial lost stroke of an operating portion such as a parking lever in a parking brake.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.
First, the configuration will be described. As shown in FIGS. 1 and 2, a brake operation cylinder 3 that opens toward one side surface of the disk rotor 2 is formed in the caliper body 1, and the caliper body 3 extends beyond the disk rotor 2. An extended bridge-shaped member 1a is provided, and the bridge-shaped member 1a is formed with an opposing portion 1c capable of pressing the other side surface of the disk rotor 2.

The cylinder 3 has a large-diameter portion 3a extending away from the disk rotor 2, that is, extending rearward, and a small-diameter portion 3b is formed coaxially therewith so as to communicate therewith, and the rear end thereof is open. A cup-shaped piston 4 is provided on the large-diameter portion 3a.
Are slidably fitted with the closed end wall facing the opening end on the disk rotor 2 side in a state where the rotation is restricted in a liquid-tight manner, and the plug 5 is liquid-tight and slidable in the small diameter portion 3b. The fitting forms a hydraulic chamber 6 in the cylinder 3. The hydraulic chamber 6 communicates with a master cylinder 3 (not shown).

On both sides of the disk rotor 2,
Brake pads 7a and 7b, which are braking members, are provided respectively. The brake pad 7a on the cylinder 3 side
Is movable in the axial direction of the disk rotor 2,
The other brake pad 7b is supported in a state where rotation is restricted, and rotation of the other brake pad 7b is also restricted. However, the brake pad 7b is moved by the facing portion 1c in the opposite axial direction to the pad 7a and pressed against the disk rotor 2. Is provided.

In the hydraulic chamber 6, an adjuster 8 composed of two members is provided. The adjuster 8 is composed of a spindle 9 having an external thread engraved on the outer circumference and a sleeve nut 10 having an internal thread engraved on the inner surface. The adjuster 8 has a required clearance corresponding to the return amount of the cup type piston 4. And screwed. A step 10a is formed in the sleeve nut 10 of the adjuster 8, and the step 10a
A disc spring 12 is interposed between the circlip 11 attached to the inner peripheral wall of the cup-shaped piston 4 and the sleeve nut 10 is urged by the cup-shaped piston 4 toward the bottom of the blind hole. In FIG. 1, reference numeral 13 denotes a thrust bearing.

The spindle 9 has the screw portion screwed to the sleeve nut 10 as described above, and the shaft portion 10a extending rearward following the screw portion.
b is engaged with the plug 5 fitted to the small diameter portion 3b. A clip 14 such as a C-ring is provided between the neck of the head 10b and the end face of the plug 5 on the hydraulic pressure chamber 6 side.

The plug 5 is restricted in rotation to the small diameter portion 3b and fits in a liquid-tight manner, and its rear end is open to the atmosphere.
A return spring 16 is provided between the clip 14 and a spring receiving member 15 fixed to the caliper body 1, and the plug 5 and the spindle 9 are biased rearward by the return spring 16. A recess 5a is formed in the rear end surface of the plug 5, and the recess 5a
A connecting rod 16 that abuts one end side extends rearward, and the other end abuts a notch of a cylindrical cam 17, and the cam 17 is connected to a parking hopper as an operation unit via a parking cable. I'm in contact.

The connecting rod 16 and the cam 17 constituting the parking operation member are disposed in a parking housing 18 which is separate from the caliper main body 1. It is rotatably supported in the parking operation chamber 18a. The parking housing 18 has an opening at the front end side, a female screw is engraved on the inner peripheral surface of the opening 18b, and the small diameter portion 3b of the caliper main body 1 has an internal thread at the outer periphery of the rear end side 3c. A male screw that can be screwed is threaded, and the parking housing 18 is assembled to the caliper body 1 by screwing between the two 18b and 3c. In FIG. 1, 19 in the nut to position the parking housing 18.

When the brake pedal is depressed, the master cylinder is operated, and the hydraulic pressure from the master cylinder causes the cup-type piston 4 to move toward the disk rotor 2 to move one brake pad 7a to the disk rotor 2. 2, the caliper body 1 moves in the opposite direction due to the reaction, and the other brake pad 7b presses the disc pad 7a via the facing portion 1c.

When the parking lever is operated, the cam 17 is rotated via the parking cable by an amount corresponding to the stroke of the parking lever, and the plug 5 is connected via the connecting rod 16 to the disc against the return spring. Push to rotor 2 side. Then, the cup type piston 4 is pushed toward the disk rotor 2 via the adjuster 8 engaged with the plug 5, and the brake pad 7a is pressed against the disk rotor 2 in the same manner as described above.

The parking operation member is a cam 1
Although seven mechanisms are used, a lever mechanism, a screw mechanism, or the like may be used instead. In the disc brake with parking as described above, the parking housing 18 is provided with respect to the caliper body 1.
Since it is assembled by screw fitting as described above, it is possible to easily assemble and finely adjust the amount of assembly of both in the axial direction of the cylinder 3. That is, the positions of the plug 5 and the adjuster 8 pressed by the connecting rod 16 when the parking brake is released can be corrected.

As shown in FIG. 3, the threaded portion between the spindle 9 and the sleeve nut 10 in the adjuster 8 is in a brake released state (FIG. 3 (b)) due to the precision of the screw teeth and assembly errors. From the time of brake operation (Fig. 3
(A) When the spindle 9 has backlash at the time of shifting to (a) and the caliper body 1 and the parking housing 18 are integrally formed as in the related art, the backlash cannot be dealt with. In the example, as described above, when assembling the parking housing 18,
An annular spacer 20 having a thickness corresponding to the amount of backlash is interposed between the rear end of the caliper body 1 and the parking housing 18 so that the cylinder of the parking housing 18 with respect to the caliper body 1 3
By adjusting the assembling position in the axial direction, it is possible to suppress the initial rattling stroke generated in the parking lever.

Further, depending on the tightening position of the nut 19,
It is possible to adjust the assembly position location of the parking housing 18. The backlash amount is as small as 0.35 mm, for example, but when converted into the stroke amount of the parking lever, it becomes as large as 13.9 mm and cannot be ignored.

The shape and the like of the parking operation member are different depending on the on-vehicle requirements of the parking cable. In such a case, if only the parking housing 18 is changed to one that meets the on-vehicle requirements, this problem can be solved. Often, there is no need to change the caliper body 1, which is the body of the brake. Also, when it is desired to change the specific value of the caliper in response to abnormal noise such as squeal, it is possible to respond by replacing the caliper main body 1 with a parking housing 18 having a different mass without changing the caliper body 1.

In the above embodiment, the caliper main body 1 and the parking housing 18 are assembled by a screw action. However, as shown in FIG.

[0028]

As described above, in the disc brake with parking of the present invention, the entire caliper needs to be changed by simple means in order to change the in-vehicle requirements of the parking cable and the eigenvalue of the caliper against abnormal noise. And also absorbs build-in clearance such as backlash of adjuster 8 by simple means,
There is an effect that an initial lost stroke can be prevented from being generated in the operation unit of the parking brake.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a disc brake with parking according to an embodiment of the present invention.

FIG. 2 is a rear view showing the disc brake with parking according to the embodiment of the present invention;

FIG. 3 is a diagram illustrating engagement of the adjuster according to the embodiment of the present invention;

FIG. 4 is a side sectional view showing the assembly of the caliper body and the parking housing according to the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Caliper main body 2 Disk rotor 3 Cylinder 3a Large diameter part 3b Small diameter part 4 Piston 5 Plug 6 Hydraulic chamber 8 Adjuster 16 Connecting rod 17 Cam 18 Parking housing 18a Parking working chamber

Claims (2)

(57) [Scope of request for utility model registration] 1. A cylinder which is formed on a caliper and is opened to a disk rotor side, and the cylinder comprises a large diameter portion, a small diameter portion, and a parking working chamber in order from the disk rotor side, and the cylinder has a large diameter portion. A piston having the open end side as a closed end wall is fitted in a liquid-tight and slidable manner to define a hydraulic pressure chamber, and an adjuster formed by screwing two members into each other in the hydraulic pressure chamber. The adjuster is provided coaxially with the piston, and a small-diameter portion side of the adjuster is engaged with a plug that is fitted to the small-diameter portion so as to be liquid-tight and movably in the axial direction. In a disk brake with parking provided with a parking operating member for moving the plug in the axial direction, the parking operating chamber forming portion is formed separately from the caliper body, A disk brake with parking, characterized in that a spacer is interposed between end surfaces of the lipper body and the parking working chamber forming portion which face each other in the moving direction of the cup type piston. 2. The disc brake with parking according to claim 1, wherein said parking working chamber forming portion is screwed into said caliper body.