JPH0543556B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a disc brake device for a motorcycle, and particularly to a brake caliper of a front wheel disc brake device.

Conventional technology Recently, disc brake devices have been widely used as brake devices for motorcycles.This disk brake device consists of an annular brake disk fixed to the wheel and a brake disk fixed to the vehicle body side with the brake disk sandwiched from both sides. The brake caliper includes a brake caliper that is pushed toward the brake disc by hydraulic pressure,
A piston is provided which presses a friction pad interposed therebetween against the surface of the brake disc.

In general, motorcycles have two types of brake systems: a lever system that performs braking by manually operating a brake lever attached to the handlebar, and a pedal system that performs braking by operating a brake pedal attached to the lower side of the vehicle body with the foot. Equipped with two brake systems,
Usually, the lever system brakes the front wheels, and the pedal system brakes the rear wheels.

Therefore, in a motorcycle equipped with a disc brake device, when the brake pedal is operated, hydraulic pressure is sent to the brake caliper of the rear wheel, and also to the brake caliper of the front wheel. There are some that allow braking to be done with both.

Problems to be Solved by the Invention The present invention aims to provide a front wheel brake caliper for a motorcycle as described above that can provide a well-balanced braking force and is lightweight and compact.

Means and Effects for Solving the Problems Therefore, in the present invention, in a brake caliper for a motorcycle that brakes the front wheel by pinching a brake disc fixed to the front wheel of the motorcycle, the brake caliper is operated by a brake lever. A piston and a piston actuated by a brake pedal are provided in parallel, and the diameter of the piston actuated by the brake lever is made larger than the diameter of the piston actuated by the brake pedal.

In a motorcycle where the front wheel can be braked by both the brake lever and the brake pedal as described above, when the brake pedal is operated, the front and rear wheels are braked at the same time, so the braking force acting on the front wheel is Even if it is relatively small, the necessary braking force can be obtained as a whole. Therefore, in the present invention,
As mentioned above, by reducing the diameter of the piston operated by the brake pedal, the brake caliper was made lighter and more compact.

On the other hand, when the brake lever is operated, only the front wheels are braked, so the diameter of the piston operated by the brake lever is made large to obtain sufficient braking force.

In this way, a well-balanced braking force can be obtained for the motorcycle as a whole.

Embodiment This embodiment will be described below with reference to the illustrated embodiment. Figure 1 is a side view of the main parts showing the arrangement of the brake equipment in a motorcycle, with front wheel 1 and rear wheel 2.
are connected by a vehicle body frame (not shown). The front wheel 1 is rotatably supported by a front fork 3. Reference numeral 4 denotes a handle, which is provided above the front fork 3 and protrudes from the left and right sides of the vehicle body. A front brake disk 5 is fixed to the side of the front wheel 1 and rotates together with the front wheel 1. A front brake caliper 6 is fixed to the lower part of the front fork 3. The front brake caliper 6 has a substantially U-shaped cross section, is disposed straddling the outer circumferential side of the front brake disc 5 with the front brake disc 5 in between, and faces the surface of the front brake disc 5. Two sets of cylinders 7 and 8 are provided in parallel. The front brake disc 5 is, as shown in FIG.
It may be installed so as to straddle the inner circumferential side of the A similar rear brake disc 9 and rear brake caliper 10 are also provided on the rear wheel 2, and the rear brake caliper 10 is provided with one cylinder 11.

A master cylinder 12 is fixed to the handle 4, and a brake lever 13 is pivotably supported on the master cylinder 12. When the brake lever 13 is pulled toward the handle 4 by hand, the piston in the master cylinder 12 is pressed by the brake lever 13 to generate oil pressure, and this oil pressure passes through the brake pipe 14 to the cylinder 7 of the front brake caliper 6. , 8.
15 is a brake pedal, which is pivotally connected to the vehicle body frame, and by stepping on the tread 16 with the tip of the foot, the brake pedal
7 to operate the piston of the master cylinder 18. The master cylinder 18 is fixed to the vehicle body frame. 19 is a reservoir tank for replenishing the master cylinder 18 with hydraulic oil. Hydraulic pressure generated in the master cylinder 18 by operating the brake pedal 15 is sent to the cylinder 11 of the rear brake caliper 10 via the brake pipe 20, and is also sent to the cylinder 11 of the rear brake caliper 10 through the brake pipe 20.
through cylinder 8 of front brake caliper 6
Also sent to. That is, by stepping on the brake pedal 15, both the rear wheel 2 and the front wheel 1 are braked.

FIG. 2 is a piping system diagram of the brake device, in which each caliper 6, 10 is shown in a simplified cross section. The front brake caliper 6 is an opposed cylinder type caliper, and the cylinder 7 is composed of two cylinders 7a and 7b facing each other with the front brake disc 5 in between, and the cylinder 8 is also composed of two cylinders 8a and 8b facing each other. It's on. The brake pipe 14 has two passages 1
4a and 14b, and the passage 14a is connected to the cylinder 7.
In a, passage 14b communicates with cylinder 7b. Similarly, the brake piping 21 also has two passages 21.
a and 21b, and these passages communicate with cylinders 8a and 8b, respectively. Each cylinder 7
Pistons 22, 22 and 23, 23 are fitted into a, 7b and 8a, 8b, respectively, and brake pads 24, 25 are inserted between these pistons 22, 23 and the front brake disc 5, respectively. ing. As shown in the figure, the rear brake caliper 10 has one cylinder 11 on only one side of the rear brake disc 9, and the brake pipe 20 communicates with this cylinder 11. A piston 26 is fitted in the cylinder 11, and is pushed out by hydraulic pressure to press the brake pad 27a against the rear brake disc 9. At the same time, the main body of the rear brake caliper 10 moves to the opposite side due to a reaction, and is pushed out to the other side. The brake pad 27b is brought into pressure contact with the opposite surface of the rear brake disc 9, and the rear brake disc 9 receives braking action from both sides.

In the front brake caliper 6, pressure oil from the master cylinder 12 is sent to two opposing cylinders 7a, 7b, and each piston 22 presses the corresponding brake pad 24 against each surface of the front brake disc 5. Similarly, pressure oil from the master cylinder 18 is also transmitted to the two opposing cylinders 8.
a, 8b, front brake disc 5
is pinched from both sides by the brake pads 25, 25. The diameter A of the piston 22 that is activated by operating the brake lever 13 is larger than the diameter B of the piston 23 that is activated by operating the brake pedal 15. Therefore, when operating the brake lever 13 to brake only the front wheels, a relatively large braking force is applied to the front brake disc 5, but when operating the brake pedal 15, the braking force applied to the brake pedal 15 is relatively small. . However, when the brake pedal 15 is operated, the rear wheels are also braked through the rear brake caliper 10, so that sufficient braking force necessary for the motorcycle as a whole can be obtained. In this way, in this embodiment, a balanced and appropriate braking force can be obtained as a whole. Furthermore, by making the piston 23 small in diameter, the front brake caliper 6 becomes smaller and lighter.

Effects of the Invention As described above, in the present invention, in a brake caliper for a motorcycle that brakes the front wheel by pinching a brake disc fixed to the front wheel of the motorcycle, a piston operated by a brake lever and a brake pedal are connected to each other. The piston operated by the brake lever is provided in parallel with the piston operated by the brake lever, and the diameter of the piston operated by the brake pedal is made larger than that of the piston operated by the brake pedal. The front wheel brake caliper is small and lightweight, and provides well-balanced braking force.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a side view of the main parts showing the arrangement of the brake device in a motorcycle, and FIG. 2 is a piping system of the brake device showing a simplified cross-section of each caliper. 3 are side views showing other embodiments of the front wheel brake device. 1...front wheel, 2...rear wheel, 3...front fork,
4...Handlebar, 5...Front brake disc,
6...Front brake caliper, 7...Cylinder,
8...Cylinder, 9...Rear brake disc, 10
...Rear brake caliper, 11...Cylinder, 12
...Master cylinder, 13...Brake lever, 14
...Brake piping, 15...Brake pedal, 16...
Tread surface, 17...axis, 18...master cylinder, 19...
Reservoir tank, 20, 21...Brake piping, 2
2, 23... Piston, 24, 25... Brake pad, 26... Piston, 27... Brake pad.

Claims (1)

[Claims] 1. A brake caliper for a motorcycle that brakes the front wheel by pinching a brake disc fixed to the front wheel of the motorcycle, in which a piston operated by a brake lever and a piston operated by a brake pedal are provided in parallel, A brake caliper characterized in that a diameter of a piston actuated by the brake lever is larger than a diameter of a piston actuated by the brake pedal.