JPH0648027B2 - Disc brake device for motorcycles - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake device for a motorcycle, and more specifically, a hydraulic pressure generating device for generating hydraulic pressure by pushing a piston rod, and the hydraulic pressure generating device. A caliper that is integrally formed with a brake disc pressure device that operates by receiving hydraulic pressure generated by the device is placed on the brake disc entry side of the vehicle body frame, and a mounting bracket that supports the caliper is pivotally supported on the axle shaft. However, the present invention relates to a disc brake device for a motorcycle that generates the hydraulic pressure of the hydraulic pressure generation device by pulling a brake wire.

[Conventional technology]

A conventional disc brake device for motorcycles is a brake disc that receives a hydraulic pressure generated by a hydraulic pressure generator that generates hydraulic pressure by pushing a piston rod that responds to a brake actuator such as a brake lever or a brake pedal. It is known that a device and a pair of friction pads that squeeze both side surfaces of a brake disc by the brake disc pressure device operated by the hydraulic pressure are incorporated into a caliper,
In this case, the hydraulic pressure generator is arranged at another position on the vehicle body frame separated from the caliper together with the hydraulic fluid reservoir communicating therewith, and is connected to the hydraulic pressure generator via a relatively long brake hose. What is done is common.

However, in the above, since the brake hose is relatively long, it is difficult to handle it, and a relatively large space is required for installing the hydraulic pressure generator and the reservoir,
Further, there have been inconveniences such as the troublesome installation work.

Therefore, as disclosed in, for example, Japanese Patent Publication No. 60-575, a hydraulic pressure generator that generates hydraulic pressure by pushing the piston rod and a brake that operates by receiving the hydraulic pressure generated by the hydraulic pressure generator. A caliper equipped with a disc pressure device is placed on the brake disc entry side of the body frame,
While supporting the caliper on the vehicle body frame via the torque rod on the feed side of the brake disc, the mounting bracket supporting the caliper is pivotally supported on the axle shaft, and the brake wire is connected to one end of a lever pivotally supported on the caliper, There is known a disc brake device in which the other end of the lever is brought into contact with the rear end of the piston rod and the piston rod is pushed by pulling the brake wire to generate the hydraulic pressure of the hydraulic pressure generator.

[Problems to be Solved by the Invention]

However, a disc brake device of the type described above
Since the piston rod is pushed by the pulling of the brake wire to generate the hydraulic pressure of the hydraulic pressure generator, the pulling force of the brake wire corresponding to it is required to obtain the predetermined braking hydraulic pressure, and the brake lever and the brake pedal are required. It is necessary to give a relatively large operating force to the brake actuator such as
Also, in order to reduce this operating force, the second arm of the lever that contacts the rear end of the piston rod must be made longer than the first arm of the lever to which the brake wire is connected. The large size makes the caliper installation work troublesome.

Therefore, an object of the present invention is to provide a relatively small disc brake device for a motorcycle by obtaining a stronger braking force by a self-servo action.

[Means for Solving the Problems]

The present invention has been made to achieve the above object,
A caliper equipped with a hydraulic pressure generating device that generates hydraulic pressure by pushing the piston rod and a brake disc pressure device that operates by receiving the hydraulic pressure generated by the hydraulic pressure generating device is installed on the brake disc rotating body frame. Located on the entrance side, the mounting bracket supporting the caliper is pivotally supported on the axle shaft,
In a disc brake device for a motorcycle, which generates a hydraulic pressure of the hydraulic pressure generation device by pulling a brake wire, a rear end of the piston rod protruding from the hydraulic pressure generation device is pivotally supported on a vehicle body frame, and the brake is applied. The brake wire is connected to the caliper so that the caliper moves in the direction in which the brake disc is drawn out by pulling the wire.

[Work]

Therefore, by pulling the brake wire, the caliper moves in the direction in which the brake disc moves out, and the piston rod relatively moves in the operating direction, so that the hydraulic fluid in the hydraulic pressure generator is boosted and the brake disc is pressed by the brake disc pressure device. And the braking torque generated by this braking is applied to the hydraulic pressure generating device itself, and this self-servo action further pressurizes the boost hydraulic fluid in the hydraulic pressure generating device.

〔Example〕

An embodiment in which the present invention is applied to a piston-opposed disc brake will be described below with reference to the drawings.

A front wheel having a brake disc 4 fixed to one side of a wheel hub 3 is rotatably supported on an axle shaft 2 whose both ends are pivotally supported by a front fork 1 which constitutes a vehicle body frame. On the disc entry side,
A disc brake 5 is arranged.

The disc brake 5 includes a pair of friction pads 6 and 7 arranged on both side surfaces of the brake disc 4, a caliper 9 that suspends the friction pads 6 and 7 with two hanger pins 8 and 8, and the caliper. 9 and the mounting bracket 10 extended to 9.

The caliper 9 is composed of a combination of caliper divisions 9a and 9b, and cylinders 11 and 12 respectively formed facing the caliper divisions 9a and 9b, and movable in the cylinders 11 and 12. Pistons 13 arranged to face each other,
Brake disk pressure device 15 is provided.

Liquid chambers 16 and 17 are defined between the bottom walls of the cylinders 11 and 12 and the pistons 13 and 14, respectively.
17 is connected by a communication pipe 18.

One of the caliper split bodies 9a constituting the caliper 9 is provided with a master cylinder 19 serving as a hydraulic pressure generating device on the outer peripheral side of the brake disc 4 and the caliper 9 on the inner peripheral side of the brake disc 4. The mounting bracket 10 for supporting is extended, and the tip of the mounting bracket 10 is pivotally supported on the axle shaft 2.

The master cylinder 19 has a piston rod 21 inserted into the cylinder 20 to define a hydraulic chamber 22 between the tip of the piston rod 21 and the bottom wall of the cylinder 20, and the hydraulic chamber 22 and the hydraulic chamber 22. The hydraulic chamber 16 is communicated with the through hole 11a, and the rear end 21a of the piston rod 21 is projected from the open end of the cylinder 20, and the rear end 21a is supported by the support shaft 23 in the same direction as the axle shaft 2. It is pivotally supported on the stay 24 of the front fork 1.

On the upper wall of the master cylinder 19, a relief port 25
And a supply port 26 is bored, and both ports 25, 2
6 and a hydraulic fluid reservoir 27 fixed to the vehicle body side are communicated with each other via a hose 28, and the reservoir 27 and the cylinder 20 are communicated with each other via a hose 28 and both ports 25, 26.

Further, a brake wire 30 is connected to a locking projection 29 provided on an upper wall of the master cylinder 19 on the front fork 1 side. The brake wire 30 is pulled by the caliper 9 when the brake wire 30 is pulled.
The brake wire 30 is inserted into the locking projection 29 and is locked by the locking piece 31a attached to one end of the brake wire 30. The piston rod 21 is inserted into the tube 30a locked to the stay 24 in the substantially same direction as the moving direction of the piston rod 21, and the locking piece 31b at the other end is connected to the brake lever 33 attached to the handle 32. Further, a conical coil spring 34 is provided on the outer periphery of the brake wire 30 between the locking projection 29 and the stay 24, and the elastic force of the coil spring 34 causes the caliper 9 to intersect the axle shaft 2. The brake wire 30 is stretched while being urged in the disc turning-in direction.

Since the present embodiment is configured as described above, when the brake lever 33 is gripped and a brake operation is performed, the caliper 9 is pulled by the pulling of the brake wire 30 so that the mounting bracket 1 is attached.
With 0, the axle shaft 2 is pivoted to the disc squeezing side, so that the piston rod 2 of the master cylinder 19
1 is relatively moved in the operating direction to increase the pressure of the hydraulic fluid in the hydraulic chamber 22 at the tip of the piston rod 21. This boosted hydraulic fluid is fed to the liquid chamber 16 through the through hole 11a, and the piston 1
3 to push the friction pad 6 against one side surface of the brake disc 4, and further through the communication pipe 18 to the liquid chamber 17
When entering, the piston 14 is pushed to press the friction pad 7 against the other side surface of the brake disc 4, whereby the brake disc 4 is braked by the sandwiching pressure of the friction pads 6, 7. Moreover, due to the braking torque to the disc feeding side, which is generated by this braking action, the caliper 9 further rotates to the disc feeding side, and a so-called self-servo action is generated in which the piston rod 21 is relatively moved in the operating direction. And the inside of the hydraulic chamber 22 is reduced to further pressurize the pressurizing hydraulic fluid.

Therefore, according to the disc brake device of the present embodiment, stronger braking force can be exerted by the self-servo action in addition to the brake operating force of the brake lever 33.

Further, by removing the mounting bracket 10 from the axle shaft 2, the disc brake 5 can be rotated around the support shaft 23 as a fulcrum, so that the replacement of the pads, the air bleeding operation in the hydraulic fluid, and the like can be easily performed. It

In the above embodiment, the caliper opposed to the piston has been described, but it is also applicable to a floating caliper having a piston only on one side, a double disc brake device, and a master cylinder or a mounting bracket. It may be formed as a separate body and integrally fixed to the caliper by screwing or welding. Further, the present brake device is not limited to the front wheels, but can be applied to the rear wheels by supporting the rear forks and the rear wheel axle shafts.

〔The invention's effect〕

As described above, the present invention is provided with the hydraulic pressure generating device that generates the hydraulic pressure by the pushing of the piston rod, and the brake disc depressurizing device that operates by receiving the hydraulic pressure generated by the hydraulic pressure generating device. The caliper is disposed on the brake disc entry side of the vehicle body frame, the mounting bracket supporting the caliper is pivotally supported on the axle shaft, and the rear end of the piston rod protruding from the hydraulic pressure generator is pivotally supported on the vehicle body frame. At the same time, since the brake wire is connected to the caliper so that the caliper moves in the direction in which the brake disc is pulled out by pulling the brake wire, a stronger braking force can be obtained by the self-servo action, and the liquid is pulled by pulling the brake wire. Even with a disc brake device that increases the hydraulic pressure of the pressure generator, a small braking force is used to ensure reliable braking. In addition to being obtained, the disc brake device can be miniaturized, its mounting work becomes easy, and moreover, the brake can be directly operated by a brake actuator such as a brake lever or a brake pedal. A hose and various parts are not required, and cost reduction and weight reduction of the vehicle body can be achieved.

In addition, when performing maintenance such as pad replacement, the work can be easily performed by removing the mounting bracket from the axle shaft and rotating the disc brake about the fulcrum of the piston rod.

[Brief description of drawings]

1 shows an embodiment of the present invention. FIG. 1 is a partially cutaway front view, and FIG. 2 is a sectional side view. 1 ... front fork, 4 ... brake disc, 5
...... Disc brakes, 6, 7 ...... Friction pads, 9 ......
Calipers, 9a, 9b ... Caliper split bodies, 10 ... Mounting brackets, 11, 12 ... Cylinders, 13, 14 ...
… Piston, 15 …… Brake disk pressure device, 19
... master cylinder, 20 ... cylinder, 21 ... piston rod, 21a ... rear end of piston rod 21, 2
3 ... Support shaft, 24 ... Stay, 27 ... Reservoir, 28
…… Hose, 29 …… Locking protrusion, 30 …… Brake wire, 31a, 31b …… Locking piece, 33 …… Brake lever, 34 …… Coil spring

Claims (1)

[Claims] 1. A caliper equipped with a hydraulic pressure generating device for generating hydraulic pressure by pushing a piston rod, and a brake disc depressurizing device which operates by receiving hydraulic pressure generated by the hydraulic pressure generating device. In a disc brake device for a motorcycle, which is arranged on a brake disc entry side of a frame, a mounting bracket for supporting the caliper is pivotally supported on an axle shaft, and a hydraulic pressure of the hydraulic pressure generator is generated by pulling a brake wire. , A rear end of the piston rod projecting from the hydraulic pressure generator is pivotally supported on a vehicle body frame, and a brake wire is connected to the caliper so that the caliper moves in a direction in which a brake disc is drawn by pulling the brake wire. A disc brake device for a motorcycle, which is characterized in that