JP2001301595A - Front-and-rear interlocking brake device for motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce changes in the attitude of a vehicle body under a wider variety of driving conditions and efficiently distribute braking forces by changing according to the vehicle speed at the time when the supply of hydraulic pressure to a front wheel brake starts, in a front-and-rear interlocking brake device for a motorcycle in which a single master cylinder outputting the hydraulic pressure as a rider operates a brake operating member is connected with the front and rear wheel brakes. SOLUTION: An index matching the operating force of the brake operating member 1A is detected by a detection means 14A, and if the index detected by the detection means 14A is equal to or less than a set index, the master cylinder 2A is shut off from the front wheel brake BF by a cutoff valve 13 and the set index is set to decrease as the vehicle speed increases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single master cylinder for outputting hydraulic pressure in response to a rider operating a brake operating member, which is connected to a front wheel brake and a rear wheel brake, respectively. The present invention relates to a front-rear interlocking brake device for a motorcycle.

[0002]

2. Description of the Related Art Conventionally, such a front-back interlocking brake device has
For example, it is already known in Japanese Utility Model Laid-Open No. 15562/1990.

[0003]

In such a front-rear interlocking brake device, when the front wheel brake and the rear wheel brake are operated in conjunction with each other, the rear wheel brake is operated in advance. Conventionally, it has been conventionally performed to reduce the change in the posture of the vehicle body by actuating the front wheel brakes with a delay, and the brake operating member of the master cylinder is common to the front wheel brakes and the rear wheel brakes. The hydraulic pressure supply from the master cylinder to the front wheel brake is cut off until the operating force applied to the vehicle reaches the set value.

However, in the above-mentioned conventional vehicle, the point at which the supply of hydraulic pressure from the master cylinder to the front wheel brake is fixed is fixed, and the effect of cutting the supply of hydraulic pressure to the front wheel brake is reduced. You will be restricted. For example, when the motorcycle is running at a higher speed, it is desirable that the front wheel brake be operated with a small operating force in order to increase the braking force.

The present invention has been made in view of such circumstances, and the point at which the supply of hydraulic pressure to the front wheel brake is started is changed in accordance with the vehicle speed. It is an object of the present invention to provide a front-rear interlocking brake device for a motorcycle in which the posture change is small and the braking force is efficiently distributed.

[0006]

In order to achieve the above object, the present invention provides a single master cylinder which outputs a hydraulic pressure in response to a rider operating a brake operating member, comprising a front wheel brake and a front wheel brake. In a motorcycle front-rear interlocking brake device connected to a rear wheel brake, a detecting unit that detects an index corresponding to an operation force of the brake operating member, and an index detected by the detecting unit is equal to or less than a set index. In the state, a cut valve for shutting off between the master cylinder and the front wheel brake is provided, and the set index is set so as to decrease as the vehicle speed increases.

According to such a configuration, the front wheel brake is started to operate with a lower operating force at the time of high-speed running, and a large braking force can be obtained with a small operating force. The front wheel brake is activated in a state where the force is higher, the front wheel brake is not actuated until the operation is performed with a large operating force, and the posture change of the vehicle body is reduced under a wider driving situation, and efficient The braking force can be distributed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 and 2 show a first embodiment of the present invention. FIG. 1 is a hydraulic circuit diagram of a brake device for a motorcycle, and FIG. 2 is a rear-wheel brake pressure with respect to a rear-wheel brake pressure. FIG.

First, in FIG. 1, when a rider of a motorcycle operates a brake lever 1A as a brake operating member with a left hand, a hydraulic pressure is output from an output port 4A of a master cylinder 2A provided with a reservoir 3A. The hydraulic pressure is output from the output port 4B of the master cylinder 2B provided with the reservoir 3B in response to the output of the brake lever 1B operated by the rider of the motorcycle with the right hand.

An output port 4A of the master cylinder 2A is connected to a rear wheel brake BR via a normally open solenoid valve 5A, and the normally open solenoid valve 5A is connected to a rear wheel brake BR.
A check valve 6A that allows the brake fluid to flow from the master cylinder 2A to the master cylinder 2A is connected in parallel. The rear wheel brake BR is connected to the reservoir 1 via a normally closed solenoid valve 7A.
0A.

The front wheel brake BF includes a pair of pots 11, 11 and a pot 12 disposed between the pots 11, 11. The output port 4B of the master cylinder 2B is connected to the front wheel wheels. Brake BF
The pots 11 and 11 are connected via a normally-open solenoid valve 5B, and the normally-open solenoid valve 5B is provided with a check valve 6B that allows the flow of brake fluid from the front wheel brake BF to the master cylinder 2B side. Connected in parallel. The two pots 11 are connected to the reservoir 10 via a normally closed solenoid valve 7B.
B.

The output ports 4A and 4B of the master cylinders 2A and 2B are connected to the discharge sides of pumps 8A and 8B for pumping the brake fluid from the reservoirs 10A and 10B, respectively. It is driven by a motor 9.

The normally open solenoid valve 5A, the check valve 6A and the normally closed solenoid valve 7A constitute control valve means VA, and the normally open solenoid valve 5B, the check valve 6B and the normally closed solenoid valve 7B. Constitutes control valve means VB.

Such control valve means VA, VB allow the master cylinders 2A, 2B to communicate with the pots 11, 11 of the rear wheel brake BR and the front wheel brake BF, as well as the rear wheel brake BR and the front wheel brake. The pots 11, 11 of the wheel brake BF are connected to the reservoirs 10A, 10A.
B, the master cylinders 2A, 2B are connected to the rear wheel brake BR and the front wheel brake BF.
Of the rear wheel brake BR and the front wheel brake BF.
And a master cylinder 2A, 2B is cut off from the pot 11, 11 of the rear wheel brake BR and the front wheel brake BF, and the rear wheel brake B is cut off.
It is possible to execute antilock control in which the pressure reduction state in which the pots 11 and 11 of the R and front wheel brake BF are communicated with the reservoirs 10A and 10B is controlled by on / off duty control of each of the solenoid valves 5A and 5B; 7A and 7B. .

The pumps 8A and 8B continue to operate during the antilock control.
R and the brake fluid discharged from the pots 11 and 11 of the rear wheel brake BR and the front wheel brake BF while being cut off from the pots 11 and 11 of the front wheel brake BF are returned to the master cylinders 2A and 2B. Accordingly, occurrence of overstroke of the brake levers 1A and 1B is avoided.

The front wheel brake B is connected between the output port 4A of the master cylinder 2A and the pump 8A via a normally open solenoid valve 5C and a normally closed solenoid valve 13 as a cut valve.
A check valve 6C connected to the pot 12 of F and allowing the flow of brake fluid from the pot 12 side to the master cylinder 2A side is connected in parallel to the normally-open solenoid valve 5C, and the normally-open solenoid valve 5C And a normally closed solenoid valve 7C which constitutes the control valve means VC in cooperation with the check valve 6C is provided between the normally open solenoid valve 5C and the normally closed solenoid valve 13 and the reservoir 10A.
And provided between them.

This control valve means VC can be controlled by selectively switching the hydraulic pressure of the pot 12 to three states of increasing, maintaining and reducing the hydraulic pressure in the same manner as the above-described control valve means VA and VC. On / off of the solenoid valves 5C and 7C is duty-controlled.

The opening timing of the normally closed solenoid valve 13 is controlled by a control unit (not shown).
In this control unit, for example, each master cylinder 2
Detecting means 14A, 14B for detecting the output hydraulic pressures of A, 2B
Is detected. Thus, when only the brake lever 1A is operated, the control unit opens the normally closed solenoid valve 13 in response to the index detected by the detection means 14A exceeding the set index. Normally closed solenoid valve 13
, And the setting index is set by the control unit so as to decrease as the vehicle speed increases. When it is determined that both of the brake levers 1A and 1B are operated based on the detection values of the two detection units 14A and 14B, the control unit determines whether or not the brake levers 1A and 1B are operated, regardless of the detection value of the detection unit 14A. The valve 13 is opened.

Next, the operation of the first embodiment will be described. When only the brake lever 1A of the two brake levers 1A and 1B is operated, the hydraulic pressure output from the master cylinder 2A is applied to the rear wheel brake. While acting on BR, it can also be supplied to the pot 12 of the front wheel brake BF. However, an index corresponding to the operating force of the brake lever 1A is detected by the detecting means 14A. When the detected index is equal to or smaller than the set index, the normally closed solenoid valve 13 is provided between the master cylinder 2A and the pot 12 of the front wheel brake BF.
, The rear wheel brake BR is operated in advance, and the front wheel brake BF is operated later, so that the posture change of the vehicle body can be reduced.

Further, the set index is set so as to decrease as the vehicle speed increases. As shown in FIG. 2, when the vehicle speed increases, the rear wheel side brake pressure is lower and the front wheel side brake pressure is lower. The brake pressure of the front wheel is increased, so that a large braking force can be obtained with a small operating force at a high speed running, and the operation of the front wheel brake BF starts at a high operating force at a low speed running. Thus, the front wheel brake BF is not actuated until the vehicle is operated with a large operating force, so that the posture change of the vehicle body can be reduced under a wider running condition, and the braking force can be efficiently distributed.

Further, when both brake levers 1A and 1B are operated simultaneously, the front wheel brake BF operates quickly without delay with respect to the rear wheel brake BR, so that emergency braking can be dealt with.

FIG. 3 shows a second embodiment of the present invention, in which the normally closed solenoid valve 13 is omitted from the first embodiment shown in FIG. Normally open solenoid valve 5 in control valve means VC
C is provided.

According to the second embodiment, the number of parts can be reduced and the same effect as that of the first embodiment can be obtained.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible.

[0026]

As described above, according to the present invention, during high-speed running, the operation of the front wheel brake is started with a lower operating force, and a large braking force can be obtained with a small operating force. When driving at low speeds, the front wheel brake starts operating with a higher operating force, and the front wheel brake is not activated until the driver operates with a large operating force. It is possible to reduce the number and to efficiently distribute the braking force.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of a brake device for a motorcycle according to a first embodiment.

FIG. 2 is a diagram showing a change in a rear wheel side brake pressure with respect to a rear wheel side brake pressure.

FIG. 3 is a hydraulic circuit diagram of a brake device for a motorcycle according to a second embodiment.

[Explanation of symbols]

 1A: Brake lever as a brake operating member 2A: Master cylinder 5C: Normally-open solenoid valve as a cut valve 13 ... Normally-closed solenoid valve as a cut valve 14A: Detection means BF・ ・ ・ Front wheel brake BR ・ ・ ・ Rear wheel brake

Claims (1)

[Claims] A single master cylinder (2A) that outputs hydraulic pressure in response to a rider operating a brake operation member (1A) includes a front wheel brake (BF) and a rear wheel brake (BR). ), A detecting means (14A) for detecting an index corresponding to the operating force of the brake operating member (1A), and an index detected by the detecting means (14A). Is below the set index, the master cylinder (2A)
And a cut valve (13, 5C) for shutting off between front wheel brakes (BF), wherein the setting index is set so as to decrease as the vehicle speed increases. Brake device.