JPH0537891Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a so-called integrated type automobile brake system in which an anti-skid control device (also called an anti-lock device, etc.) and a hydraulic booster are combined.

(Prior art) Conventionally, as an automobile brake system, for example, "Nitsun Service Bulletin No. 549" (February 1985,
A device as described on pages C-41 to C-54 of Nissan Motor Co., Ltd. is known.

This conventional device includes a vacuum booster that uses engine negative pressure to increase the force applied to the brake pedal, a master cylinder that converts the output from the vacuum booster into brake fluid pressure, and a cylinder that connects the master cylinder and wheel cylinder. It was equipped with an anti-skid control device installed in the middle of a conduit that connected the brake fluid to the brake fluid, and increased, maintained, and decreased the brake fluid pressure in a direction to prevent wheels from locking.

The anti-skid control device is designed to drain brake fluid from the wheel cylinder side to the master cylinder side in order to prevent the brake pedal position from displacing in the direction of depression if the brake fluid is drained when the pressure is reduced and the subsequent brakes becoming ineffective. An anti-skid pump was installed to supply and maintain the amount of brake fluid in the pipeline.

(Problem to be solved by the invention) However, in such conventional automobile brake systems, a vacuum booster whose braking force is determined by the diameter of the diaphragm is used as a booster, and the booster has a large Because of this, there was a request to make the booster more compact by using a hydraulic booster.

Therefore, when a hydraulic booster is applied in place of a vacuum booster, in vehicles equipped with an anti-skid control device, such as the conventional example, the hydraulic booster pump, which is the hydraulic pressure source for the hydraulic booster, and the anti-skid pump of the anti-skid device and a motor that requires different drive control for each pump.
The increase in the number of parts and the necessity of two motor drive control systems poses a problem of high costs.

(Means for solving the problem) The present invention was made with the purpose of solving the above-mentioned problems, and in order to achieve this purpose, the present invention increases the pressing force on the brake pedal. A booster, a master cylinder that converts the output from the booster into brake fluid pressure, and a pipe that connects the master cylinder and wheel cylinder are installed in the middle of the pipe, and the brake fluid is pumped in the direction of preventing wheels from locking. An automobile brake system is equipped with an anti-skid control device that increases, maintains, and reduces pressure, and the anti-skid control device includes an anti-skid pump that supplies brake fluid from the wheel cylinder side to the master cylinder side when the pressure is reduced. The hydraulic power device is a hydraulic booster, the hydraulic booster pump and the anti-skid pump are driven by one motor, and the anti-skid pump side is provided with pump action stopping means for stopping the pump action when the anti-skid control is not activated. This means that it is characterized by the fact that it has been established.

(Function) In the automobile brake system of the present invention, since the above-mentioned means are used, the hydraulic booster pump and the anti-skid pump are driven by one motor,
Although one of the anti-skid pumps is driven by one motor, the pumping action of one of the anti-skid pumps is stopped by a pump action stopping means when the anti-skid control is not activated.

Therefore, one of the anti-skid pumps needs pumping action only when the anti-skid control to suppress wheel slip is activated during brake operation.
The pump for the other hydraulic booster requires a pump action independent of the anti-skid control operation, and the different pump operation requirements can be met while using one motor, reducing the number of parts by sharing the motor and reducing the number of pump operations. It is possible to achieve both satisfaction of requirements.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In describing this embodiment, an automobile brake system equipped with an electronically controlled four-wheel anti-skid control device and a hydraulic booster will be taken as an example.

First, the configuration will be explained.

As shown in FIG. 1, the automobile brake system B of the embodiment includes a brake pedal 1, a hydraulic booster 2,
master cylinder 3, brake hydraulic pipes 4, 5,
It is equipped with a wheel cylinder 6, a booster hydraulic circuit C, an anti-skid control device A, a hydraulic booster pump 7, an anti-skid pump 8, and a motor 9.

The hydraulic booster 2 is a booster that increases the pressing force on the brake pedal 1 by using an increase in internal oil pressure, and the input side is connected to the brake pedal 1.
The output side is connected to the piston of the master cylinder 3.

In addition, since the hydraulic booster 2 is a known device,
A detailed explanation of the internal configuration will be omitted (see Japanese Patent Application Laid-Open No. 110651/1983).

The master cylinder 3 is connected to the hydraulic booster 2
This device converts the output from the master cylinder 3 into brake fluid pressure.A reservoir tank 10 for storing brake fluid is provided at the top of the master cylinder 3, and the pressure fluid from the master cylinder 3 is transferred from brake fluid pressure pipes 4 and 5 to each wheel. wheel cylinder 6 (only one wheel is shown in the drawing).

The wheel cylinder 6 is formed within a brake caliper 11 constituting a disc brake device, and when brake fluid pressure is supplied from the brake fluid pressure pipe 4 into the wheel cylinder 6 during brake operation, the pads are applied to the brake disc 12. Press to apply braking force to the wheels.

The booster hydraulic circuit C includes an inlet pipe 22 that connects the reservoir chamber 20 defined by the internal partition wall 10a of the reservoir tank 10 and the input port 21 of the hydraulic booster pump 7.
and an outlet pipe 25 that connects the output port 23 of the hydraulic booster pump 7 and the input port 24 of the hydraulic booster 2.

In addition, a relief valve 26 is provided in the connecting oil passage between the inlet pipe 22 and the outlet pipe 25 to release the hydraulic pressure to the inlet pipe 22 side when the hydraulic pressure on the outlet pipe 25 side reaches the upper limit pressure or more. It is provided.

Further, an accumulator 27 and a pressure sensor 28 are provided in the middle of the outlet pipe 25.

The anti-skid control device A controls the brake fluid pressure in a direction to prevent wheels from locking by controlling the operation of a three-position solenoid valve 30 provided in the middle of a brake fluid pressure pipe 4 that connects the master cylinder 3 and the wheel cylinder 6. A device that increases, maintains, and reduces pressure, and has a front wheel speed sensor 31 and a rear wheel speed sensor 32 as input sensors, an electronic control circuit 33 as a control module, and a 3-position solenoid valve 30 as a control actuator. .

The three-position solenoid valve 30 has a pressure increasing part 30a, a holding part 30b, and a pressure reducing part 30c, and the master cylinder side pipe 4a, the wheel cylinder side pipe 4b, and the inlet bypass pipe 34 of the brake fluid pressure pipe 4 are connected. has been done.

The inlet bypass pipe 34 is connected to an input port 35 of the anti-skid pump 8, and an outlet bypass pipe 37 connects the bypass pipe 34, the output port 36 of the anti-skid pump 8, and the master cylinder side pipe 4a. A bypass circuit is constructed by the above.

Incidentally, a reservoir tank 38 is provided in the middle of the inlet bypass pipe 34.

The hydraulic booster pump 7 and anti-skid pump 8 will be explained with reference to FIG. 2.

Both pumps 7 and 8 are driven by one motor 9 and share a pump body 90, and an eccentric cam 92 provided on an output shaft 91 of the motor 9 drives each pump 7, 8 through a bearing 93.
The driving force is input to 8.

The hydraulic booster pump 7 includes a cylindrical cylinder 70 fitted in a pump body 90, a plunger 71 that is provided in the cylinder 70 so as to be able to slide back and forth and has one end in contact with the bearing 93, and the plunger 71 is connected to the bearing 93. It is constituted by a spring 72 that biases in the direction and a pump chamber 73 in which the spring 72 is housed.

In addition, the input port 21 of the hydraulic booster pump 7
An inlet check valve 74 is provided on the side, and an outlet check valve 75 is provided on the output port 23 side.

Two anti-skid pumps 8 are provided at symmetrical positions (one is not shown), and include a cylindrical cylinder 80 installed in a pump body 90, and a cylinder 80 mounted in a pump body 90.
The plunger 81 includes a plunger 81 that is slidably reciprocally slidable on the plunger 8 and has one end in contact with the bearing 93, and a pump chamber 82 that is formed at the other end of the plunger 8.

In addition, the input port 3 of the anti-skid pump 8
An inlet check valve 83 is provided on the 5 side, and an outlet check valve 84 is provided on the output port 36 side.

In this way, both pumps 7 and 8 are connected to the plunger 7.
The anti-skid pump 8 has a positive displacement pump configuration that performs pumping action by reciprocating the parts 1 and 81 by motor rotation, but the anti-skid pump 8 omits the spring and uses a plate from the wheel cylinder 6 side that occurs only when pressure is reduced. By using the hydraulic pressure as a signal hydraulic pressure and configuring the pump to perform the pump action when the anti-skid control is activated (in the embodiment, only when the pressure is reduced), a pump action stopping means that stops the pump action when the anti-skid control is not activated is constructed. has been done.

The motor 9 is controlled to be turned on and off by a command signal from a motor drive control circuit included as an internal circuit in the electronic control circuit 33. The motor drive control circuit has the following input sensors:
The pressure sensor 28 and the brake switch 40 are included.

Next, the effect will be explained.

(a) When anti-skid control is not activated First, the motor drive control when anti-skid control is not activated will be explained with reference to the flowchart shown in FIG. In this flowchart, it is assumed that the pressure signal from the pressure sensor 28 and the switch signal from the brake switch 40 are read at any time.

In step a, it is determined whether the signal from the brake switch 40 is ON, in step b it is determined whether the anti-skid control is activated, and in step c it is determined whether the pressure P in the outlet pipe 25 is below the lower limit pressure Pmin. A determination is made, and in step d, it is determined whether the pressure P in the outlet pipe 25 is higher than the upper limit pressure Pmax, in step e, an ON command is output to the motor 9, and in step f, an OFF command is output to the motor 9, In step g, it is determined whether the signal from the brake switch 40 is OFF.

Therefore, when the brake is operated and the anti-skid control is not activated, step a → step b →
The process proceeds to step c, and if P<Pmin, the process proceeds to step e, where the motor 9 starts driving. Then, the pressure P gradually increases and when P>Pmax, step c → step d → step f
The motor 9 is stopped.

That is, when the anti-skid control is not activated and P≦Pmax, the motor 9 is driven, and the reciprocating motion of the plunger 71 of the hydraulic booster pump 7 causes air to be sucked in from the input port 21 through the inlet check valve 74. Oil is pump room 7
3, and the altretto check valve 75
from the output port 23 to the accumulator 2
7 and becomes the hydraulic pressure source for the hydraulic booster 2.

At this time, the anti-skid pump 8 is also driven, but since the inlet bypass pipe 34, which is the inflow side conduit, is closed by the 3-position solenoid valve 30, oil does not flow into the pump chamber 82. Since the plunger 81 is not pushed back toward the bearing 93, it does not function as a pump.

(b) When the anti-skid control is activated When the anti-skid control is activated, the flow from step a to step b to step e to step g is repeated in the flowchart of FIG. 3, and the motor 9 is always in a driving state. .

Therefore, when the anti-skid control is activated, the inlet bypass pipe 34, which is the inflow side pipe,
When the pressure is reduced by opening the 3-position solenoid valve 30, the second
As shown in the figure, pressurized oil in the wheel cylinder 6 passes through the inlet bypass pipe 34 and flows into the reservoir tank 38, and due to the reciprocating movement of the plunger 81 of the anti-skid pump 8, the oil is transferred from the input port 35 to the inlet check valve. The oil sucked in through the pump chamber 83 is pressurized in the pump chamber 82, passes through the throttle check valve 84, and is supplied from the output port 36 to the master cylinder 3 side. At this time, the pressure generated within the pump chamber 82 becomes a force that pushes the plunger 81 back toward the bearing 93, and a pumping action is exerted.

Note that when this anti-skid control is activated, the hydraulic booster pump 7 also operates at the same time and cannot be stopped.
The pressure lever may exceed the upper limit pressure Pmax, but when the upper limit pressure Pmax is exceeded, the relief valve 26 opens and suppresses the pressure increase of the pressurized oil sent to the hydraulic booster 2.

In addition, even when anti-skid control is activated,
Inlet bypass pipe 3, which is the inflow side pipe line
4 is closed by the 3-position solenoid valve 30 during pressure increase or maintenance, the anti-skid pump 8 does not act as a pump, and as a result, the anti-skid pump 8 acts during the entire operation of the anti-skid control operation. It is possible to eliminate the accumulator (installed in the outlet bypass pipe) for storing excess oil when necessary.

As explained above, in the automobile brake device A of the embodiment, the following effects can be obtained.

Since the booster is a hydraulic booster 2, and the hydraulic booster pump 7 and the anti-skid pump 8 are driven by one motor 9, the number of parts can be reduced by sharing the motor, and the device It is also advantageous in terms of cost.

Since the anti-skid pump 8 side has a pump configuration without a spring so that the pump action is stopped when the anti-skid control is not activated, one of the anti-skid pumps 8 is activated only when the anti-skid control is activated to suppress wheel slip during brake operation. It is possible to satisfy different pump operation requirements, such as requiring a pump action and the other hydraulic booster pump 7 requiring a pump action independent of anti-skid control operation, while using one motor 9.

Since the hydraulic booster pump 7 and the anti-skid pump 8 have an integrated structure that shares the pump body 90, it is advantageous in terms of pump cost compared to a case where the pumps are each configured independently.

Since the anti-skid pump 8 performs the pumping action only when the pressure is reduced during the anti-skid control operation, the anti-skid pump 8 performs the pumping action during the entire operation of the anti-skid control operation, including when increasing and maintaining the pressure. The necessary accumulator can be abolished.

The pump action is controlled only when the pressure is reduced by directly using the hydraulic pressure generated during the pressure reduction, without using sensors or actuators, so the pump action can be controlled with a simple device configuration. .

Relief valve 2 is installed in the booster hydraulic circuit C.
6, it is possible to prevent the hydraulic pressure applied to the hydraulic booster 2 from becoming high during anti-skid control operation.

Next, other examples of the hydraulic booster pump 7 and the anti-skid pump 8 shown in FIG. 4 will be described.

In another example, a one-way clutch 86 is provided between the motor output shaft 91 and the pump drive shaft 85 of the anti-skid pump 8, and when the motor 9 rotates in the normal direction, rotation is transmitted to the pump drive shaft 85 of the anti-skid pump 8. However, when the motor 9 rotates in the reverse direction, the power is not transmitted, and the hydraulic booster pump 7 is configured to be driven both when the motor 9 rotates in the forward direction and in the reverse direction. Note that other configurations are the same as those in the above example, so the same reference numerals are used in the drawings and explanations thereof will be omitted.

Therefore, in this other example, the anti-skid pump 8 is not driven when the anti-skid control is not activated, so that the durability of the pump 8 is improved.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention may be modified without departing from the gist of the present invention. included.

For example, in the embodiment, the spring on the anti-skid pump side was omitted to provide a pump action stopping means that stops the pump action when anti-skid control is not activated. A clutch or the like that disengages during uncontrolled operation may be used to stop pumping during uncontrolled antiskid operation.

(Effects of the invention) As explained above, in the automobile brake system of the invention, the booster is a hydraulic booster, and the hydraulic booster pump and the anti-skid pump are driven by one motor. In addition, since the anti-skid pump side is equipped with a pump action stop means that stops the pump action when the anti-skid control is not activated, the number of parts can be reduced by sharing the motor, and different pump operation requirements can be satisfied. The effect is that it is possible to achieve both.

[Brief explanation of the drawing]

Fig. 1 is an overall schematic diagram showing an automobile brake system according to an embodiment of the present invention, Fig. 2 is a sectional view showing a hydraulic booster pump and an anti-skid pump used in the embodiment equipment, and Fig. 3 is a diagram illustrating a hydraulic booster pump and an anti-skid pump used in the embodiment equipment. FIG. 4 is a flowchart showing the flow of the control operation of the motor drive control, and FIG. 4 is a cross-sectional view showing another example of the hydraulic booster pump and anti-skid pump used in the embodiment device. B... Automobile brake system, C... Hydraulic circuit for booster, A... Anti-skid control device, 1...
...Brake pedal, 2...Hydraulic booster, 3...
Master cylinder, 4, 5...Brake hydraulic pipe, 6...Wheel cylinder, 7...Hydraulic booster pump, 8...Anti skid pump, 9
……motor.

Claims (1)

[Claim for Utility Model Registration] A booster that increases the force applied to the brake pedal, a master cylinder that converts the output from the booster into brake fluid pressure, and a pipe that connects the master cylinder and the wheel cylinder. The anti-skid control device is installed in the middle of the road and increases, maintains, and decreases the brake fluid pressure in a direction to prevent wheels from locking.The anti-skid control device applies the brake fluid from the wheel cylinder side to the master cylinder side when the pressure decreases. In an automobile brake system having an anti-skid pump for supplying fluid, the booster is a hydraulic booster, the hydraulic booster pump and the anti-skid pump are driven by one motor, and the anti-skid pump is connected to the anti-skid pump. An automobile brake device characterized in that it is provided with a pump action stopping means for stopping the pump action when the anti-skid control is not activated.