JPH0536099Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a disc brake for vehicles that performs braking action by mechanically operating friction pads. This relates to bearing holes.

[Conventional technology]

A disc brake installed as a brake for the rear wheels of a vehicle is a hydraulic brake operated by hydraulic pressure generated in a hydraulic master cylinder when the brake pedal is pressed, as disclosed in, for example, Japanese Utility Model Application Publication No. 163335/1983. A so-called parking brake system is used, which combines a pressure-type actuation mechanism and a mechanical actuation mechanism that is activated by pulling the handbrake lever.

Among these, the mechanical actuation mechanism has bearing holes extending perpendicularly to the disk axis penetrating both side walls of the caliper, and a camshaft that presses the friction pad against the disk rotor inserted through the bearing hole. ing.

The protruding shaft of the camshaft that protrudes from the opening at one end of the bearing hole has a cam lever that rotates together with the camshaft and a parking cable pulled by the handbrake lever that separates the camshaft and cam lever when the traction is released. A coil-shaped return spring is provided to return it to the operating position.
A boot is attached to the opening at the other end of the bearing hole, which is formed for removing the camshaft.

A cable arm is fixed to the caliper, and the parking cable connected to the cam lever is held in a predetermined direction in the vicinity of the connecting portion with the cam lever.

[The problem that the idea aims to solve]

In the above-mentioned configuration, the number of parts attached to the caliper is large, and not only is the manufacture and management of these parts complicated, but also the installation work is unavoidably complicated. In particular, the above-mentioned boot is made of rubber and is fitted to the outside of the caliper 6 so as to cover the other end opening of the bearing hole, so it has better strength against external forces than a metal boot. It has the disadvantage of poor weather resistance, and there is a risk that it may be dislodged by flying stones, etc., or weakened by outside air or rainwater.

Therefore, the present invention uses a cable arm as a means to close the opening at the other end of the bearing hole.
The object of the present invention is to provide a disc brake for a vehicle that solves the above-mentioned problems.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a caliper disposed astride the disc rotor through a bearing hole, and a camshaft that presses a friction pad against the disc rotor can be rotated through the bearing hole. The cam lever is inserted into the shaft, and the cam lever is pivotally attached to the protruding shaft of the camshaft that protrudes from the opening at one end of the bearing hole.
In a vehicle disc brake in which a parking cable connected to the cam lever is held by a cable arm fixed to a caliper, a plug for a bearing hole is integrally formed on the cable arm,
The cable arm is characterized in that the plug closes the other end opening of the bearing hole, and the cable arm is made of metal, synthetic resin, or the like with high rigidity and excellent weather resistance.

[Effect]

With this configuration, the opening at the other end of the bearing hole is closed by the plug by attaching the cable arm, and no special member or attachment work is required.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

A rear wheel disc brake 1 is equipped with a parking brake including a hydraulic actuation mechanism 2 and a mechanical actuation mechanism 3, and is disposed on the side of a disc rotor 4, as shown in FIG.

A caliper 6 is supported by a bracket 5 fixed to the vehicle body on one side of the disc rotor 4 through a pair of sliding pins 7, so as to be movable in the axial direction of the disc.

A pair of friction pads 8, 8 are disposed facing each other on both sides of the disc rotor 4, and an action part 6a and a reaction part 6b of the caliper 6, which are arranged with both friction pads 8, 8 in between, are connected to the disc rotor 4 and the friction pads. 8, 8 are connected at a bridge portion 6c that straddles them.

Each friction pad 8 includes a lining 8a and a back plate 8b.
The pad spring 9 attached to the ceiling opening 6d of the bridge section 6c biases the disc toward its center, and prevents rattling during running and lifting of the disc toward its outer circumference during braking. is suppressed by this pad spring 9.

The action part 6a has a large diameter hole 10a and a medium diameter hole 10b.
and a small-diameter communication hole 10c.
0 is formed in the disk axial direction, and a small-tip piston 11 is fluid-tightly and movably inserted into a large diameter hole 10a that opens toward the disk rotor 4 side, with the bottom wall 11a facing the disk rotor 4 side. has been done.

A hydraulic chamber 12 is defined between the piston 11 and the bottom of the medium-diameter hole 10b, and the medium-diameter hole 10b includes:
An inlet port 13 is formed for introducing hydraulic pressure generated by a known hydraulic master cylinder (not shown) into the hydraulic pressure chamber 12.

The above-mentioned hydraulic actuation mechanism 2 includes the above-mentioned piston 11
, a hydraulic pressure chamber 12 and an inlet port 13.
The hydraulic pressure from the hydraulic master cylinder supplied to
The piston 11 of the large diameter hole 10a, the adjuster 14 and the sleeve piston 15 of the mechanical actuation mechanism 3, which will be described later, are pushed together toward the disc rotor 4 side.

The piston 11 moving forward through the large diameter hole 10a with this supply fluid pressure presses one of the friction pads 8 against one side of the disc rotor 4, and then, due to this reaction, the caliper 6 moves toward the acting portion 6a. Reaction part 6b
However, the other friction pad 8 is pressed against the other side of the disc rotor 4, and the disc rotor 4 is pinched between the two friction pads 8, 8 to perform a braking action.

On the other hand, the mechanical actuation mechanism 3 is used for a parking brake that performs a braking action by the driver's handbrake operation, and the actuation mechanism 3 includes an adjustment bolt 1
6 and an adjuster nut 17; a sleeve piston 15 disposed across the medium diameter hole 10b and the communication hole 10c; and a camshaft 18 disposed perpendicular to the cylinder axis.
It has a push rod 19 interposed between the camshaft 18 and the sleeve piston 15.

The sleeve piston 15 connects the large-diameter shaft portion 15a disposed in the medium-diameter hole 10b to the action portion 6 with a pin 20.
a, the rear small diameter shaft portion 15b is inserted into the communication hole 10c, and the large diameter shaft portion 1
5a, a tapered clutch surface 15c and a small diameter shaft hole 15d are continuously formed.

Also, the adjustment bolt 16 is connected to the spring 2
1, the threaded portion 16a at the tip is screwed into the female threaded hole 17a of the adjuster nut 17, which engages the piston 11 unevenly to prevent rotation.
It is inserted into the shaft hole 15d of the sleeve piston 15, and the clutch surface 1 on the outer periphery of the flange 16c
6d is attached to the clutch surface 15c of the sleeve piston 15 in frictional engagement by the elastic force of the spring 22 compressed between the sleeve piston 15 and the large diameter hole 10a.

At the rear of the communication hole 10c, a bearing hole 23 that is perpendicular to the disk axis is connected to the operating portion 6a, as shown in FIG.
The bearing hole 23 is provided with openings in the upper and lower walls of the bearing hole 23.
The camshaft 18 is inserted therethrough.

The bearing hole 23 includes a large diameter hole 23a and a small diameter hole 23.
The camshaft 18 is formed into a stepped shape in which the shafts 18a and 18b are vertically connected, and the camshaft 18 is composed of an insertion shaft portion 18b having a flange portion 18a at its tip, and a protruding shaft portion 18c continuous with the insertion shaft portion 18b.

The camshaft 18 is inserted from the protruding shaft portion 18c side into the other end opening 23d on the large diameter hole 23a side, and the protruding shaft portion 18c is inserted into the one end opening 23 on the small diameter hole 23b side.
The insertion shaft portion 18b protrudes from the small diameter hole 23.
b, and the flange portion 18a is disposed within the large diameter hole 23a, and the flange portion 18a is disposed within the large diameter hole 23a.
It is rotatably supported by first and second bearings 24 and 25, which are arranged above and below, and by a third bearing 26, which is inserted between the insertion shaft portion 18b and the small diameter hole 23b. .

The bearing hole 23 into which the camshaft 18 is inserted and arranged as described above has an opening 2 at one end on the side of the small diameter hole 23b.
The boot 27 is attached to the hole 3c, and the large diameter hole 23a
The other end opening 23d on the side is closed by a plug 28a.

A cam lever 29 for rotation is provided on the protruding shaft portion 18c.
is fixed with a nut 30, and a coil-shaped return spring 32 is provided to engage between a stopper pin 31 protruding from the action portion 6a and the cam lever 29, and the camshaft 18 and the cam lever 29 are They are rotated together in the braking direction by the parking cable 33 pulled by the handbrake lever, and when this pulling is released, the restoring force of the return spring 32 returns to the non-braking position.

Among the bearings 24 to 26, the first and second bearings 24 and 25 use balls as rolling elements,
A thrust bearing that supports the axial load of the camshaft 18 via this ball roller,
The first bearing 24 is interposed with a washer 34 between the flange portion 18a and the bottom of the large diameter hole 23a, and the second bearing 25 is interposed between the flange portion 18a and the bottom of the large diameter hole 23a.
A ring-shaped retainer 35 is interposed between the plug 28a and the fitting protrusion 28b of the plug 28a.

Further, a third
The bearing 26 is a radial bearing that guides the rotation of the camshaft 18 using roller-like rolling elements.The bearing 26 is a radial bearing in which the rotation of the camshaft 18 is guided by a roller-shaped roller. , the push rod 19 passes through the bearing 26 inwardly and outwardly, and is connected to the cam groove 18d;
It is disposed between the sleeve piston 15 and a spherical recess 15e formed in the small diameter shaft portion 15b.

The camshaft 18 inserted into the bearing hole 23 is
The axial thrust load is applied to the first and second bearings 2.
4, 25, the radial load perpendicular to the axis is
Each is supported by a bearing 26 and rotation is smoothly guided.

A plug 28a provided to cover the other end opening 23d on the large diameter hole 23a side is connected to the parking cable 3.
The plug 28a is integrally formed with the aluminum alloy cable arm 28 that holds the connection part with the cam lever 29 of No. 3 in a predetermined direction.
is provided with the above-mentioned fitting protrusion 28b that fits into the large diameter hole 23a of the bearing hole 23, and the cable arm 28 itself is bent into a stepped shape.

The cable arm 28 and the plug 28a are arranged by aligning the cable arm 28 with the outer shape of the acting part 6a, fitting the fitting protrusion 28b into the large diameter hole 23a, and operating the bolts 36, 36 inserted through the plug 28a. It is attached by screwing onto the portion 6a. The cable arm 28 is provided so that the intermediate step portion 28c is joined to the upper surface and end surface of the guide boss 6e that protrudes into the action portion 6a, and the cable arm 28 is easily aligned during the above-mentioned installation, and after the installation, it is possible to Rotation is prevented when affected by the pulling force of the parking cable 33 or the parking cable 33.

A spring hole 28d is formed in the fitting protrusion 28b, and a coiled spring 37 is compressed between the spring hole 28d and the retainer 35. The spring 37 urges the camshaft 18 in the direction of the cam lever 29 with its elastic force,
The flange portion 18a is supported at the bottom of the large-diameter hole 23a to fill unnecessary axial clearance due to manufacturing errors, etc., and to restrict axial movement of the camshaft 18.

The mechanical actuation mechanism 3 of this embodiment is configured as described above, and when the parking cable 33 is pulled by the driver's handbrake operation, the camshaft 18 rotates together with the cam lever 29, and the camshaft 18 rotates in unison with the cam lever 29. The rotational force is converted into thrust by the push rod 19, which pushes the sleeve piston 15. The sleeve piston 15 is connected to the disc rotor 4
When the piston 11 moves forward toward the side, the piston 11 moves forward together with the adjusting bolt 16 and adjusting nut 17 toward the disc rotor 4, and both friction pads 8,
8 is pressed against the disc rotor 4 in the same way as in the hydraulic pressure operation described above to effect a braking operation.

When the lining 8a wears down due to repeated braking operations by the hydraulic and mechanical actuating mechanisms 2 and 3, the piston 11 to the sleeve piston 15 transfers the wear of the lining 8a toward the disc rotor 4 during braking. The vehicle moves forward and performs a braking operation. When the pressure from these operating mechanisms 2 and 3 is released, the clutch engagement between the sleeve piston 15 and the adjusting bolt 16 is released, and the adjusting bolt 16 rotates to the bottom side of the large diameter hole 10a. It protrudes and engages the sleeve piston 15 again with the clutch, stopping the adjustment bolt 16 from being extended. This allows the adjustment nut 1
7, the retraction limit of the piston 11 is regulated, and an appropriate braking gap is set by compensating for the gap due to wear of the lining 8a.

The plug 28a, which is provided by closing the opening 23d at the other end of the bearing hole 23, is disposed above the operating portion 6a, so it is easily affected by external forces such as flying stones, rain, dust, outside air, etc. Since it is made of the same metal as the cable arm 28, it has higher rigidity and strength than conventional rubber boots, and has excellent weather resistance. on the other hand,
The boot 27, which is attached to the opening 23c at one end of the bearing hole 23, is attached to the cam lever 29 below the operating portion 6a.
Because it is covered with sand, it is less affected by flying stones and climate.

Furthermore, the above-mentioned plug 28a is connected to the cable arm 2.
8 and is attached to the action part 6a together with the cable arm 28 with bolts 36, 36, so not only is there no need to manufacture and manage it as a dedicated part, but the original installation work can be omitted, resulting in lower product costs. can be reduced.

[Effect of idea]

In the vehicle disc brake of the present invention, a plug is integrally formed on the cable arm that holds the parking cable, and the plug closes the other end opening of the bearing hole through which the camshaft is inserted. The plugs can be attached at the same time by attaching them, and the work of attaching the plugs can be omitted, the number of parts can be reduced, management can be simplified, and product costs can be reduced.

In addition, since this plug is made of the same material as the cable arm, it has higher rigidity and strength than conventional rubber boots, and has excellent weather resistance, so it is protected against external forces such as flying stones, rain, dust, outside air, etc. It is not susceptible to damage and can withstand use for a long period of time.

[Brief explanation of the drawing]

The figure shows one embodiment of the present invention, and Figure 1 is a front view of a disc brake attached to a vehicle body;
2 is a cross-sectional view taken from FIG. 1, FIG. 3 is a cross-sectional view taken from FIG. 1, and FIG. 4 is a cross-sectional view taken from FIG. 1. DESCRIPTION OF SYMBOLS 1... Disc brake, 2... Hydraulic operating mechanism, 3... Mechanical operating mechanism, 4... Disc rotor, 6... Caliper, 6a... Acting part, 6e...
Guide boss, 18...Camshaft, 23...Bearing hole, 23a...Large diameter hole, 23b...Small diameter hole, 2
3c...One end opening, 23d...Other end opening, 2
7... Boot, 29... Cam lever, 32... Return spring, 33... Parking cable, 28... Cable arm, 28a... Plug, 28b... Fitting protrusion, 28c... Intermediate step,
28d... Spring hole, 36... Bolt.

Claims (1)

[Scope of utility model registration request] A bearing hole is provided in a caliper that is disposed astride the disc rotor, and a camshaft that presses a friction pad against the disc rotor is rotatably inserted into the bearing hole. A vehicular disc brake in which a cam lever is pivotally attached to a protruding shaft portion of a protruding camshaft, and a parking cable connected to the cam lever is held by a cable arm fixed to a caliper,
A disc brake for a vehicle, characterized in that a plug for a bearing hole is integrally formed on the cable arm, and the other end opening of the bearing hole is closed by the plug.