JP2004042766A - Reservoir-integrated hydraulic master cylinder for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure the sufficient amount of liquid in a reservoir integrated with a hydraulic master cylinder, and to manufacture the lightweight and compact reservoir at low cost. <P>SOLUTION: An angle θ is set between the axis CL1 of a cylinder body 11 and the axis CL2 of a liquid storage tank 11a of a reservoir 15 integrated therewith. The cylinder body 11 is fitted to a rear portion 2a of a vehicle body frame 2 with the axis CL1 inclined from the vertical line by an angle θ, and the liquid storage tank 11a is disposed thereby toward the vertical direction. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hydraulic master cylinder for hydraulically actuating a rear wheel brake or the like of a motorcycle or a three- or four-wheeled vehicle with a handlebar, and more particularly, to a reservoir-integrated hydraulic pressure integrally provided with a reservoir. Regarding the master cylinder.
[0002]
[Prior art]
As a hydraulic master cylinder used for a rear wheel brake of a motorcycle, there is one disclosed in, for example, JP-A-2000-255409.
This hydraulic master cylinder is a reservoir-integrated type that integrally has a reservoir for storing hydraulic fluid in a vertically long cylinder body that is disposed with its central axis oriented in the vertical direction of the vehicle body. Are arranged side by side with their central axes directed in the same direction, and are attached to the motorcycle so as to be integrally inclined substantially along an inclined portion such as a body frame.
[0003]
[Problems to be solved by the invention]
For this reason, the diaphragm provided inside the liquid storage tank is tilted with respect to the liquid level of the hydraulic fluid, and an unnecessary space is generated between the diaphragm and the liquid level, and the liquid volume is not enough for the capacity of the liquid storage tank. There was a problem that a sufficient amount could not be secured. Further, such a problem is also caused by the fact that the vertical portion of the body frame to which the hydraulic master cylinder is attached is small.
[0004]
The present invention has been made in view of such circumstances, and it is an object of the present invention to secure a sufficient amount of liquid inside a reservoir of a reservoir while integrally providing a reservoir in a cylinder body, and It is an object of the present invention to provide a reservoir-integrated hydraulic master cylinder for a vehicle that is compact, lightweight, and can be manufactured at low cost.
[0005]
[Means for Solving the Problems]
According to the present invention, there is provided a reservoir-integrated hydraulic master cylinder for a vehicle, in which a reservoir for storing a hydraulic fluid is integrally provided on a cylinder body disposed on the vehicle body with a central axis directed in a vehicle vertical direction according to the above-described object. Wherein the reservoir is disposed with the central axis directed vertically. Further, the cylinder body may be disposed with the cylinder center axis inclined at a predetermined angle with respect to the reservoir.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment in which the present invention is applied to a rear wheel brake of a motorcycle will be described below with reference to the drawings.
[0007]
In the motorcycle 1, a swing arm 3 is supported by a rear portion 2 a of a body frame 2 so as to swing vertically, and a rear wheel 4 is suspended at a rear end of the swing arm 3 by using a rear axle 5. A hydraulic rear wheel brake 6 is arranged between the wheel 4 and one arm 3a of the swing arm 3.
[0008]
The rear wheel brake 6 includes a disc rotor 7 that rotates integrally with one side of the rear wheel 4, a caliper bracket 8 whose base end is supported by the rear axle 5, and a caliper body 9 that is supported by a distal end of the caliper bracket 8. It consists of A hydraulic master cylinder 10 for rear wheel braking is fixed to a rear portion 2a of the body frame 2 with a cylinder body 11 directed vertically, and a brake rod 13 is attached to a push rod 12 projecting from a lower end of the cylinder body 11. The rear end is rotatably connected, and the cylinder body 11 and the caliper body 9 are connected by a brake hose 14.
[0009]
The hydraulic master cylinder 10 is a reservoir integrated type in which a liquid storage tank 11a of a reservoir 15 is integrally formed in a vertically long cylindrical shape on one upper side of a vertically long cylindrical cylinder body 11, and the cylinder body 11 and the liquid storage tank 11a are The central axes CL1 and CL2 are formed to have a predetermined angle θ.
[0010]
The cylinder body 11 has its brackets 11b, 11b bolted to a slightly inclined portion of the rear portion 2a of the body frame 2, and when the motorcycle body is positioned on the horizontal ground GL, the center axis CL1 of the cylinder body 11 Is inclined at an angle θ with respect to the vertical line VL, and the central axis CL2 of the liquid storage tank 11a is oriented in the vertical direction.
[0011]
On the center axis CL1 of the cylinder body 11, a bottomed cylinder hole 20 is provided with an open lower end. In the cylinder hole 20, a piston 21 is liquid-tight using a primary cup seal 22a and a secondary cup 22b. A hydraulic chamber 23 is defined between the piston 21 and the upper wall 11c of the cylinder hole 20 while being movably inserted.
[0012]
A return spring 24 is contracted between the piston 21 and the upper wall 11c, and the piston 21 is urged downward by a resilient force of the return spring 24, that is, in a non-operating direction, toward the lower side of the vehicle body. The limit is restricted by the contact of the push rod 12 with the head 12a, which is locked by the circlip 25 engaged with the opening of the cylinder hole 20. A union hole 26 is provided in communication with the hydraulic pressure chamber 23, and the banjo 14 a at the end of the brake hose 14 is connected to the union hole 26 using a union bolt 27.
[0013]
The reservoir 15 includes a liquid storage tank 11a integrated with the cylinder body 11, a cap 30 attached to an upper opening of the liquid storage tank 11a, and a diaphragm 31 and a diaphragm plate 32 sandwiched therebetween. A viewing window 33 for lower level confirmation is additionally provided on the rear side wall of the vehicle body of the liquid storage tank 11a.
[0014]
Inside the liquid storage tank 11a, a vertically long cylindrical liquid storage chamber 34 is provided on the central axis CL2, and the liquid storage chamber 34 and the cylinder hole 20 are separated from each other by a liquid through hole 35a, a relief port 35b, and a supply port. The hydraulic fluid is communicated between the liquid storage chamber 34 and the cylinder hole 20.
[0015]
When the motorcycle body is on the horizontal ground GL, the liquid storage tank 11a is attached to the vehicle body so that the center axis CL2 faces in the vertical direction. In the chamber 34, a predetermined liquid amount is sufficiently ensured without wasting its volume.
[0016]
Since the liquid storage chamber 34 is formed in a vertically long cylindrical shape as described above, the diaphragm 31 is provided with a bellows portion 31a that can expand and contract in the vertical direction and a cylindrical portion 31b that can expand and contract in the radial direction. . The bellows portion 31a is disposed in the space left above the liquid level of the working fluid, and the tubular portion 31b is disposed in the working fluid. Rippling is effectively prevented, and bubbles generated in the hydraulic fluid due to vibration of the vehicle body due to expansion and contraction of the cylindrical portion 31b are quickly discharged to a space above the liquid level.
[0017]
This embodiment is configured as described above, and the hydraulic master cylinder 10 for the rear wheel is located in the state of FIG. 1 when the brake pedal 13 is not depressed and is not operated. When the brake pedal 13 is depressed, the push rod 12 moves upward, pushing the piston 21 upward in the cylinder hole 20, and after the primary cup 22a closes the relief port 35b, the hydraulic pressure chamber 23 is closed. Is gradually increased in pressure.
[0018]
The hydraulic fluid pressurized in the hydraulic chamber 23 is sent from the upper union hole 26 to the caliper body 9 of the rear wheel brake 6 through the union bolt 27, the banjo 14a, and the brake hose 14, and the disk rotates integrally with the rear wheel 4. The rotor 7 is braked.
[0019]
Since the reservoir 15 integrated with the hydraulic master cylinder 10 is attached to the vehicle body with the central axis CL2 directed vertically, there is no unnecessary space above the liquid surface, and the liquid storage chamber 34 has a minimum size. At the same time, a necessary and sufficient predetermined liquid amount can be sufficiently ensured. Therefore, the reservoir 15 can be manufactured compact, lightweight and at low cost.
[0020]
Around the rear of the brake pedal 13 in which the hydraulic master cylinder 10 for rear wheel brakes is disposed, a portion in the vertical direction of the vehicle body frame 2 is generally small, but the central axis of the cylinder body 11 and the liquid storage tank 11a is small. By setting the angle θ to CL1 and CL2, the cylinder body 11 can be adjusted to the slightly inclined rear portion 2a of the body frame 2 while disposing the reservoir 15 in the vertical direction with excellent storage efficiency of the hydraulic fluid. It can be attached to.
[0021]
【The invention's effect】
As described above, according to the hydraulic master cylinder for a reservoir-integrated vehicle of the present invention, the reservoir integrated with the hydraulic master cylinder is manufactured at a compact, lightweight, and low cost, and the liquid storage chamber in the reservoir is formed. Even with the minimum size, a necessary and sufficient predetermined liquid amount can be sufficiently ensured without leaving an unnecessary space above the liquid surface. Also, by tilting the central axis of both the cylinder body of the hydraulic master cylinder and the central axis of the reservoir by a predetermined angle, the cylinder body can be mounted on the vehicle body while disposing the reservoir in the vertical direction, which is excellent for efficient storage of hydraulic fluid. Can be easily attached to the inclined portion.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a hydraulic master cylinder showing one embodiment of the present invention. FIG. 2 is a front view of a hydraulic master cylinder showing one embodiment of the present invention mounted on a vehicle body.
DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Body frame, 2a ... Rear part of body frame 2, 3 ... Swing arm, 4 ... Rear wheel, 5 ... Rear axle, 6 ... Rear wheel brake, 7 ... Disc rotor, 9 ... Caliper body, 10 ... Hydraulic master cylinder, 11: cylinder body, 11a: reservoir, 12: push rod, 12a: head of push rod 12, 13: brake pedal, 14: brake hose, 15: reservoir, 20: cylinder hole, 21 ... Piston, 23 ... Hydraulic chamber, 30 ... Cap, 31 ... Diaphragm, 31a ... Bellows, 31b ... Cylindrical part, 34 ... Reservoir, 35a ... Liquid through hole, 35b ... Relief port, 35c ... Supply port CL1: central axis of cylinder body 11, CL2: central axis of liquid storage tank 11a, θ: angle set to central axes CL1, CL2, VL: vertical line

Claims (2)

A reservoir integrated type vehicle hydraulic master cylinder in which a reservoir for storing hydraulic fluid is integrally attached to a cylinder body disposed on the vehicle body with a central axis directed in the vehicle vertical direction, wherein the reservoir has a vertical vertical axis. A hydraulic master cylinder for a reservoir-integrated vehicle, wherein the hydraulic master cylinder is disposed to face in a direction. The hydraulic cylinder for a reservoir-integrated vehicle according to claim 1, wherein the cylinder body is provided with a cylinder center axis inclined at a predetermined angle with respect to the reservoir.

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