JPH0665543B2 - Vehicle anti-skidding control device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle anti-skid control device.

[Conventional technology]

Conventionally, in order to prevent the phenomenon of wheel lock that may occur during vehicle braking, the brake hydraulic pressure related to the wheel that tends to lock the wheel is reduced, increased, or increased depending on the state of the wheel rotation speed. Further, various holding devices, that is, antiskid control devices have been proposed.

By the way, in order to make such an anti-skid control device widely used in many vehicles, in order to achieve high functionality such as high response of the anti-skid control, it is necessary to reduce the size and weight of the anti-skid control. It is also one of the issues that must be fully considered.

From such a point of view, for example, there has been proposed one in which a common hydraulic pump is commonly used for a plurality of anti-skid systems (Japanese Utility Model Publication No. 56-21640).

[Problems to be Solved by the Invention]

However, although the above-mentioned conventional proposal can share the hydraulic pump for the anti-skid control, the response of the anti-skid control is required as an apparatus that requires response control within an extremely short time of several hundred milliseconds to several seconds. Is still insufficient. That is, in the above-mentioned conventional device, since the cut valve open circuit that guarantees the operation during normal braking is given by the hydraulic pressure in the power chamber, the hydraulic pressure in the power chamber must be reduced in order to shift to anti-skid control and reduce the hydraulic pressure in the braking device. It is necessary to pull out and close the cut valve, and the time delay cannot be avoided.

For this reason, there is a demand for an anti-skid control device that realizes both device sharing and quick responsiveness, and that can easily prevent common device failures.

The present invention has been made from this point of view, and its purpose is to provide an independent anti-skid control device for each wheel, as compared with the case where an independent anti-skid control device is generally installed for each wheel.
Alternatively, for example, a hydraulic pump or accumulator that occupies a large part in terms of weight and volume between a plurality of anti-skid control devices such as a single system for the two rear wheels and an independent system for the front two wheels may be used. The purpose of the present invention is to provide an anti-skid control device that can be commonly used for practically independent control of each wheel.

Another object of the present invention is to provide a device capable of realizing reduction of pressure, pressurization, etc. of brake hydraulic pressure during anti-skid control with high responsiveness depending on the wheel rotation speed state.

Still another object of the present invention is that the piping of the normal brake system passes through only a limited part of the antiskid system, so that the failure of the antiskid control system can be prevented from occurring in the normal brake system. The purpose is to provide a device that has little effect.

[Means for Solving the Problems]

The features of the anti-skid control device according to the present invention made to realize such an object are, therefore, a master cylinder, a brake device connected so that brake hydraulic pressure is transmitted from the master cylinder, and the master cylinder. A normally open first solenoid valve provided in the middle of a path from the brake system to the braking device, and a reservoir device connected to the brake device at a position closer to the braking device than the first solenoid valve in the middle of the path; A normally closed second solenoid valve provided in the middle of a path connecting the brake device and the reservoir device, and an anti-open / close switch for the first solenoid valve and the second solenoid valve based on a command of an anti-skid control signal. With skid control device,
The reservoir device includes a reservoir piston whose one end faces a reservoir oil chamber connected to the brake device via the second electromagnetic valve, and the other end faces a control oil chamber connected to the hydraulic pressure supply / discharge electromagnetic valve device. The hydraulic pressure supply / discharge solenoid valve device has an auxiliary pressure source for the control oil chamber based on a command for brake hydraulic pressure pressurization and depressurization by the anti-skid control device, and further a hydraulic pressure holding command added as necessary. It is configured to control pressure oil supply and discharge.

In the above configuration, the signal input to each solenoid valve detects a brake hydraulic pressure holding time and a brake hydraulic pressure depressing time by, for example, detecting a sudden drop of a wheel that occurs during vehicle braking by deceleration or the like. , An electronic control circuit for a generally known anti-skid control method may be obtained by using an electronic control circuit of a method of detecting the pressurizing time of the brake hydraulic pressure by the acceleration of the wheel, etc., which is gradually recovered by the reduction of the brake hydraulic pressure. A control circuit is utilized.

[Action]

According to the present invention, it is generally desired that a solenoid valve that operates immediately in response to an anti-skid control signal based on a command from an electronic control circuit can promptly respond and that the wheels are functionally separated. By sharing one accumulator and hydraulic pump for the anti-skid control device without deteriorating their functions, the oligopoly ratio of the vehicle interior volume can be greatly improved.

〔Example〕

 The present invention will be described below based on embodiments shown in the drawings.

In FIG. 1, reference numeral 1 denotes a brake hydraulic pressure transmission path, which connects between the master cylinder M / C and the wheel cylinder W / C of the brake device. Reference numeral 3 denotes a first solenoid valve provided in the middle of the path 1, which is normally open and is closed by receiving a brake pressure holding signal from an electronic control circuit (not shown) at the time of anti-skid control as an input. When the anti-skid control is released, the normal state is restored.

Reference numeral 2 is a branch path branched and connected between the downstream position of the first solenoid valve 3 of the path 1 and the reservoir oil chamber 9 of the reservoir device 5, and 4 is a second solenoid valve provided midway, Is normally closed and is opened with the brake hydraulic pressure reduction signal and the pressurization signal from the electronic control circuit during the anti-skid control as inputs. In this example,
The second solenoid valve 4 is simultaneously switched by the same anti-skid signal as the first solenoid valve 3, including when the brake oil pressure is maintained.

The reservoir device 5 includes a cylinder 6 and a reservoir piston 7
One end of the reservoir piston faces the reservoir oil chamber 9, the other end faces the control oil chamber 10, and the return spring 8 normally biases and rests at the initial position on the reservoir oil chamber side. Has become.

A stroke switch 11 is installed on the side of the reservoir oil chamber 9 in the cylinder 6 by the fixed sleeve 12, and detects that the reservoir piston 7 is at the initial position.

According to the reservoir device having such a configuration, when the brake pressure oil is introduced into the reservoir oil chamber 9 by the opening of the second electromagnetic valve 4, the reservoir piston 7 is moved so as to balance with the hydraulic pressure of the control oil chamber 10. By moving, the brake hydraulic pressure in the reservoir oil chamber 9 is reduced, increased, or maintained.

Next, a mechanism for controlling the hydraulic pressure of the control oil chamber 10 will be described.

The control oil chamber 10 is connected to the accumulator 17 in the middle of the control oil pressure introducing path 13 via a normally closed control oil pressure introducing electromagnetic valve (hereinafter referred to as a pressurizing valve) 15, and also to an oil pressure releasing tank 18. A normally open solenoid valve for releasing control pressure (hereinafter referred to as a pressure reducing valve) 1 in the middle of the control pressure release path 14 between
It is connected via 6.

Reference numeral 19 is a hydraulic pump for pumping pressure oil from the release tank 18 to the accumulator 17, and 20 is a pumping path.

Then, the pressurizing valve 15 and the pressure reducing valve 16 in the present example.
The pressure oil supply / exhaust solenoid valve device for the control oil chamber 10 configured by means releases the oil pressure of the control oil chamber 10 in the normal time and in order to reduce the brake oil pressure, and in the pressure reducing valve 16 for maintaining the brake oil pressure. In order to pressurize the brake hydraulic pressure, the pressure reducing valve 16 is closed and the pressurizing valve 15 is opened. The antiskid signals for these operations are controlled by the electronic control circuit. Given by.

The operation of each solenoid valve of the anti-skid control device having the above configuration will be described below in light of actual vehicle braking.

During normal braking, the first solenoid valve 3, the second solenoid valve 4, the pressurizing valve 15, and the pressure reducing valve 16 are all in the illustrated state, so the brake hydraulic pressure from the master cylinder M / C is the wheel cylinder W / of the brake device. Directly communicated to C.

The hydraulic pressure in the control oil chamber 10 in the reservoir device 5 is released to the release tank 18.

At the time of anti-skid control (when the brake oil pressure is reduced) In this example, when the electronic control circuit detects the lock tendency of the wheels and outputs a brake oil pressure reduction signal, the first solenoid valve 3 is closed and the second solenoid valve 4 is closed. The open circuit of is done at the same time.
Therefore, the wheel cylinder W / C of the brake device is cut off from the communication with the master cylinder M / C, and in the present example, the switching states of the first solenoid valve 3 and the second solenoid valve 4 are the antiskid control. It continues until it is released.

Brake device wheel cylinder W /
C communicates with the reservoir oil chamber 9 of the reservoir device, and at this time, the pressurizing valve 15 and the pressure reducing valve 16 continue to be in the initial state. Therefore, in the reservoir device 5, the reservoir piston 7 inflow brakes into the reservoir oil chamber 9. It moves to the left due to the action of hydraulic pressure, so the brake hydraulic pressure is reduced. The stroke switch may detect that the reservoir device has entered the anti-skid control state, and may warn the driver to that effect as necessary.

(Holding Brake Hydraulic Pressure) Holding the brake hydraulic pressure is performed by closing the pressure reducing valve 16 from the state during the pressure reducing. That is, the hydraulic pressure in the control oil chamber 10 is substantially locked by this closed path, and the left movement of the reservoir piston 7 is stopped.

(At the time of pressurizing the brake hydraulic pressure) The pressurization of the brake hydraulic pressure is performed from the pressure maintaining valve 1
This is done by opening 5. That is, the pressure oil of the accumulator 17 is introduced into the control oil chamber 10 by this open circuit, and the volume of the reservoir oil chamber 9 is reduced by the right movement of the reservoir piston 7 to pressurize the brake oil pressure.

In the case of this example, the time point when the stroke switch 11 detects the return of the reservoir piston 7 to the initial (normal) position is regarded as the end of the anti-skid control, and this detection information is used to detect the first solenoid valve 3 and The second solenoid valve 4 can be returned to the normal state.

According to the above configuration, since the supply and discharge of the pressure oil to and from the control oil chamber of the reservoir device can be controlled by the operation of the pressurizing valve and the pressure reducing valve, one set of accumulator and pump, and the release tank are
Even when connected in parallel to a plurality of pressure oil supply / exhaust solenoid valve devices, the operation of each reservoir device depends on the operating state of each pressure oil supply / exhaust solenoid valve device, and the reservoir device of another system Have virtually no effect on each other, and thus generally
An accumulator or the like, which tends to be large in terms of volume, can be shared by the anti-skid control devices of all systems of the vehicle, and in this case, the effect of reducing the weight and size of the entire device is extremely large. FIG. 2 shows a case where the essential part of the antiskid control device shown in principle in FIG. 1 is configured as a concrete implementation product. The same parts as the figure are shown.

As is clear from FIG. 2, the master cylinder
The first solenoid valve 3 is only provided in the middle of the connection path 1 between the M / C and the wheel cylinder W / C, so the failure of the anti-skid control system almost affects the normal braking system. There is a benefit of not doing it.

〔The invention's effect〕

According to the present invention described above, since pressure reduction, pressurization, and holding as necessary for anti-skid control of brake hydraulic pressure are given by opening / closing switching of various paths by a solenoid valve, control with excellent responsiveness can be achieved. Since the pump and the accumulator, which are pressure oil sources, can be commonly used for a plurality of wheels without any hindrance, there is an effect that the size and weight of the entire vehicle can be reduced.

Further, according to the anti-skid control device of the present invention, the first solenoid valve and the second solenoid valve are provided for the anti-skid control with respect to the brake hydraulic pressure transmission path of the normal brake system.
Since it is only an electromagnetic valve, therefore, the failure of the hydraulic pressure supply / discharge electromagnetic valve device and the hydraulic pressure source for this purpose is detected by a simple detection means to release the operation of these first electromagnetic valve and second electromagnetic valve. There is also an effect that it is possible to take measures against the failure of the anti-skid control system with only such a simple configuration.

[Brief description of drawings]

Drawing FIG. 1 is a schematic structural view showing an embodiment of an anti-skid control device according to the present invention, and FIG. 2 is a partial vertical sectional view of a concrete example of the device. 1 ... Brake hydraulic pressure transmission path 2 ... Branch path 3 ... First solenoid valve (normally open type) 4 ... Second solenoid valve (normally closed type) 5 ... Reservoir device 6 ... Cylinder, 7 ... Reservoir Piston 8 Return spring 9 Reservoir oil chamber 10 Control oil chamber 11 Stroke switch 12 Fixed sleeve 13 Control oil pressure introduction passage 14 Control oil pressure release passage 15 Pressurizing valve (normal (Closed type) 16 ... Pressure reducing valve (normally open type) 17 ... Accumulator 18 ... Release tank, 19 ... Pump.

Claims (1)

[Claims] 1. A master cylinder, a brake device connected so that brake hydraulic pressure is transmitted from the master cylinder, and a normally open type first intermediate member provided in the middle of a path from the master cylinder to the brake device. A solenoid valve, a reservoir device connected to the brake device at a position closer to the brake device than the first solenoid valve in the middle of the path, and a normally closed type interposed in the middle of the path connecting the brake device and the reservoir device. Second solenoid valve, and an anti-skid control device that switches between the first solenoid valve and the second solenoid valve to open and close based on a command of an anti-skid control signal, and the reservoir device has one end of the second solenoid valve. Has a reservoir piston facing the reservoir oil chamber connected to the brake device through the other end and the other end facing the control oil chamber connected to the hydraulic pressure supply / discharge solenoid valve device,
The hydraulic pressure supply / discharge solenoid valve device supplies pressure oil of an auxiliary pressure source to the control oil chamber based on a command for brake hydraulic pressure pressurization and depressurization by the anti-skid control device, and a hydraulic pressure holding command added as necessary. An anti-skid control device for a vehicle, which controls discharge.