JPH0238423B2 - SHARINROTSUKU BOSHISOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a wheel lock prevention device used in a vehicle such as a motorcycle or a wheeled vehicle, and more specifically, to a brake fluid pressure transmission system, and a reservoir mechanism for releasing fluid pressure. This invention relates to a wheel lock prevention device in which a pump mechanism for circulating brake fluid into a brake fluid pressure transmission system is bypass-connected.

Conventionally, anti-skid devices equipped with pneumatically actuated pressure reducing devices release the pressure fluid in the brake fluid pressure transmission system to the reservoir mechanism when the brake fluid pressure needs to drop, and when the brake fluid pressure needs to rise again. A switching valve-type antiskid device (wheel lock prevention device) has been proposed in which the fluid stored in the reservoir mechanism is returned to the brake fluid pressure transmission system using a pump mechanism. It is known for its characteristics of being suitable.

Here, to describe the basic configuration of such a switching valve type wheel lock prevention device, there is a brake fluid pressure transmission path (hereinafter referred to as the main path) that connects the master cylinder (hydraulic pressure generation source) and the brake device. is a normally open first on-off valve (hereinafter simply referred to as the first on-off valve) that is normally open and closed when brake fluid pressure needs to drop.
A bypass route (hereinafter referred to as the bypass route) is provided to this main route, and the bypass route and the main route are separated so as to be closed at all times. In addition, a normally closed second on-off valve (hereinafter referred to simply as the second valve) that closes when it is necessary to lower the brake fluid pressure is disposed, and this bypass path has an internal volume that is increased by the pressure of the inflowing brake fluid. The first valve (normally open type) and the first The opening/closing operation of the two valves (normally closed type) is performed by an electronic control circuit that detects wheel lock during vehicle braking.

Generally, the first valve and the second valve are electromagnetically operated solenoid valves.

By the way, in the wheel lock prevention device having such a basic configuration, it is assumed that the operating state in which the first valve and the second valve close the flow path causes a difference in the hydraulic pressure between the liquid systems on both sides of the valve. Therefore, when the valve is closed, it is naturally subject to different hydraulic pressure actions from both sides, and the valve is kept closed by electromagnetic force within the necessary range, or when it is necessary to open the valve, this different hydraulic pressure is applied. The valve body must be moved by electromagnetic force against hydraulic pressure.

For this reason, the required electromagnetic force is quite large, and the power consumption is also large, so that although the advantage of miniaturizing the entire device can be obtained, various problems still remain.

In view of the above-mentioned circumstances, the present invention has been made with the first object of reducing the power consumption of a solenoid valve in a switching valve type wheel lock prevention device as much as possible.

Another object of the present invention is to make it possible to reduce brake fluid pressure with good responsiveness when wheels become locked during vehicle braking.

Still another object of the present invention is to configure the reservoir mechanism provided in the bypass path to be structurally independent from the first valve, thereby eliminating restrictions on the structure of the reservoir mechanism and reducing machining. The purpose of this is to reduce the requirements for precision, etc., and to prevent unnecessary pressure fluid from flowing into the reservoir mechanism during anti-skid operation, and also to prevent fluctuations in the pedal stroke.

The gist of the present invention is to provide a main path for transmitting brake fluid pressure connected between a master cylinder and a brake device, a normally open first valve interposed in this main path, and a first valve of a normally open type interposed in this main path. a bypass path that is bypassed by connecting the second valve and the liquid pump mechanism to the main path between the first valve and the brake device;
a reservoir mechanism provided in the bypass path, and the second valve is a normally closed electromagnetically operated valve that electromagnetically separates a valve body seated on an open valve seat on the main path side by a spring thrust. In the wheel lock prevention device, two sets of independent piston mechanisms are provided in the bypass path, each of which moves against the force of a set spring under the hydraulic action of the inflow pressure liquid when the second valve is opened, and these piston mechanisms The wheel lock prevention device is characterized in that one of them is the reservoir mechanism, and the other is a driving device for switching the opening and closing of the first valve, with a narrow path extending from the piston facing the main path.

According to the present invention, in response to the opening of the second valve, which is an electromagnetically operated valve, the first valve is closed, and the pressure fluid flows into the reservoir mechanism (storage) immediately in response to only the hydraulic action. Moreover, since the drive device for closing the first valve is formed separately and independently from the reservoir mechanism, various excellent effects can be obtained, such as being able to be configured as an extremely responsive device. It became.

Note that the present invention is applicable to both front and rear wheel control of a motorcycle, left and right wheel control, and all wheel control of an automobile (four-wheeled vehicle).

Embodiments of the present invention will be described below based on the principle configuration diagram shown in the drawings.

In the figure, 1 is a brake pedal, 2 is a master cylinder that generates hydraulic pressure according to the pedal force, and 3 is a brake pedal.
6 is a hydraulic pressure transmission pipe that connects the master cylinder 2 to the input port 4 of the valve device, and 6 is a hydraulic pressure transmission pipe that connects the output port 5 of the valve device to the brake device 7, connecting the input and output ports 4 and 5. These hydraulic pressure transmission pipes 3 and 6, including the flow path 8, constitute a main path. In the following explanation, these will be referred to as main path 3,
6 and 8.

Reference numeral 9 denotes a normally open first valve inserted in the main path 8, and is composed of a valve seat 10, a ball 11, a hold spring 12, and a locking rod 13 extending from a valve opening/closing piston, which will be described later. Normally, the ball 11 is separated from the valve seat 10 by the locking rod 13 to open the flow path (as shown), and when the locking rod 13 moves to the lower side of the figure as described later, the ball 11
is seated on the valve seat 10 by the spring force of the hold spring 12, and operates to close the flow path.

Therefore, the main paths 3, 6, and 8 normally transmit the hydraulic pressure generated by the master cylinder 2 to the brake device, but do not transmit hydraulic pressure when the first valve 9 is closed. Note that this first valve 9 is configured to naturally allow the return of pressure fluid in the opposite direction (from the brake device to the master cylinder) when the brake is released.

14 is a bypass passage connected to the main passage 8 in the valve device, and a normally closed second passage.
A valve 15 and a pump mechanism 21 for pumping up hydraulic pressure are connected as connection parts. Here, in the second valve 15, the valve body 17 is seated against the open valve seat 16 on the main path 8 side by the spring force of the hold spring 19, and the movable iron core 18 integrated with the valve body 17 is attached to the solenoid 20. The valve body 17 is configured to be separated from the valve seat 16 when electromagnetically attracted by the excitation of the valve body 17 .

The solenoid 20 is energized using a known anti-skid control circuit (not shown) that detects wheel lock during vehicle braking, so that it is energized when brake fluid pressure needs to be reduced.

The pump mechanism 21 includes, for example, a pair of tick valves 22 and 23, a reciprocating plunger 24, and an eccentric cam 25 that is assembled to an axle and rotates to cause the plunger 24 to reciprocate.

A characteristic feature of the present invention is that two sets of piston mechanisms are provided in the bypass path 14, one of which is used for driving the opening and closing of the first valve 9, and the other is used as a reservoir mechanism.

To explain this below, first, the piston mechanism 26 for driving the first valve opening/closing is composed of a cylinder 27 opened to the bypass path 14, a valve opening/closing piston 28 slidingly fitted to the cylinder 27, and a set spring 29. Opening/closing piston 28
A small diameter portion, which forms the locking rod 13 of the first valve 9, is formed to protrude from a part of the valve. 30 is a seal ring. Reference numeral 31 designates a piston cup that liquid-tightly seals the sliding surface of the narrow diameter portion that penetrates the body wall of the valve device.This may have a two-way sealing property, but it is a piston cup that provides a seal against failure of the pump mechanism, etc. From the idea, from the bypass route 14 to the main route 8
It is practically desirable to use a one-way seal (for example, the above-mentioned piston cup) that can allow leakage of pressure fluid to the piston cup.

In the piston mechanism 26 having such a configuration, the required stroke of the valve opening/closing piston 28 may be the amount of movement required to close the first valve 9 (the ball 11 seats on the valve seat 10), and the amount of movement required to close the first valve 9 (the ball 11 seats on the valve seat 10), and to open the second valve 15. There are several factors that are problematic in operating the first valve 9 to close in immediate response to the operation, such as the diameter of the piston 28, the spring force value of the set spring 29, and the locking rod protruding into the main path 8. 13, the seal resistance of the seal ring 30 and the piston cup 31, etc., and in other words, there is an advantage that there is no restriction on design requirements from other components. Specifically, when the piston mechanism is also used as a reservoir, it is desirable to increase the diameter of the piston from the perspective of expanding the amount of stored liquid, but on the other hand, this causes a delay in closing the first valve. , and the small diameter portion extending from the piston is the first
The structure used as the locking rod 13 of the valve 9 is extremely effective in reducing the spring force value of the set spring 29 and therefore improving responsiveness by reducing the piston diameter.

Also, the piston mechanism 3 constituting the second reservoir
3, this is the bypass path 14
It consists of a cylinder 34 that opens into the cylinder 34, a reservoir piston 35 that slides into the cylinder 34, and a set spring 36. Note that 37 is a seal ring.

In the reservoir mechanism having such a configuration, the second
When the valve opens, the pressure fluid flowing in from the main path 8 causes the reservoir piston 35 to move against the set spring 36, increasing the chamber volume and causing a drop in the brake fluid pressure value. In this case, by arbitrarily selecting the piston diameter, the spring force value of the set spring, etc., it is possible to store a large amount of liquid, and it is also suitable for vehicles that use large diameter pistons in the brake system. The overall operation of the wheel lock prevention device shown in the drawings can be fully understood through the configuration and operation of each part described above. Following the electromagnetic opening operation of the second valve 15, the first valve 9 closes, and the pressurized fluid in the brake device 7 flows into the reservoir mechanism 33 to cause a drop in fluid pressure, thereby eliminating wheel lock. When this lock is released and the second valve 15 closes, the pump mechanism 21 pumps up the fluid in the reservoir to the main path, forming an overall system that once again increases the fluid pressure in the brake device.

According to the configuration of the present invention, since the electromagnetic force for operating the entire system is required only in the second valve section, it has the advantage of low power consumption, and also has the advantage that the electromagnetic force that operates the entire system is small. A closed circuit of one valve is obtained, which alleviates the problem of unnecessary flow of pressure fluid into the reservoir from the master cylinder side, and also simplifies the design of each part of the device.
Since it is possible to select operating conditions that suit various different vehicles, this type of wheel lock prevention device is extremely useful for practical use.

[Brief explanation of drawings]

The drawings are diagrams showing the basic configuration of an embodiment of the present invention. 1: Brake pedal, 2: Master cylinder,
3, 6: Hydraulic pressure transmission pipe (main path), 4: Input port,
5: Output port, 7: Brake device, 8: Flow path (main path), 9: First valve, 10: Valve seat, 11: Ball, 12: Hold spring, 13: Locking rod,
14: Bypass path, 15: Second valve, 16: Valve seat, 17: Valve body, 18: Movable iron core, 19: Hold spring, 20: Solenoid, 21: Pump mechanism, 22, 23: Check valve, 24: Plunger, 25: Eccentric cam, 26: Piston mechanism, 2
7: Cylinder, 28: Valve opening/closing piston, 2
9: Set spring, 30: Seal ring, 3
1: Piston cup, 33: Piston mechanism (reservoir mechanism) 34: Cylinder, 35: Reservoir piston, 36: Set spring, 37: Seal ring.

Claims (1)

[Claims] 1. A main path for transmitting brake fluid pressure connected between the master cylinder and the brake device, a normally open first on-off valve interposed in this main path, and a first on-off valve of the brake device from this first on-off valve. A bypass path that is bypassed by using a second on-off valve and a liquid pump mechanism as a connection part with respect to the main path between, and a reservoir mechanism provided in this bypass path,
In the wheel lock prevention device, the second on-off valve is a normally-closed electromagnetically operated valve that electromagnetically separates a valve body seated on an opening valve seat on the main path side by a spring thrust, and the bypass path includes: Two sets of independent piston mechanisms are provided which move against the set spring force under the hydraulic action of the inflow pressure liquid when the second on-off valve is opened, and one of these piston mechanisms is used as the reservoir mechanism, and the other is A wheel lock prevention device characterized in that a narrow diameter portion extending from the piston faces the main path and is used as an opening/closing switching drive portion of the first opening/closing valve.