JPH07246923A - Hydraulic controller - Google Patents

Abstract

PURPOSE:To provide an inexpensive hydraulic controller which improves pedal feeling. CONSTITUTION:This hydraulic controller is provided with a master cylinder 190, which has a reservoir chamber 13 and the first pressure chamber 11 being partitioned by the first piston 14 shifting by a brake pedal 22 and the second pressure chamber 12 being partitioned by the second piston 15 and leading to the reservoir tank 21, a first hydraulic control circuit 27, which pumps up oil from a discharge passage 31 by a pump 50 and adjusts the oil pressure of the first pressure chamber 11, and a second hydraulic control circuit 28, which adjusts the oil pressure of the second pressure chamber and gives it to the second wheel cylinder. Furthermore, this provided with a changeover valve 26 which changes over the communication between the reservoir tank and the first pressure chamber and the reservoir chamber and the communication between the reservoir tank and the discharge passage of a the first hydraulic control circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device capable of performing an anti-lock brake function for preventing wheel lock and a traction control function or an automatic brake function for preventing wheel slip.

[0002]

2. Description of the Related Art An apparatus of this type is disclosed in Japanese Patent Laid-Open No. 64-7.
The technique disclosed in Japanese Patent No. 4153 is known. The wheel braking control device disclosed in the above publication relates to a wheel braking control device having an antilock brake circuit between a master cylinder and a wheel cylinder. In this technique, a 3-port 2-position traction control switching valve is provided in the passage between the master cylinder and the antilock brake circuit. When the brake pedal is depressed, this traction control switching valve connects the master cylinder and the wheel cylinder via the antilock brake opening / closing valve, so that the master cylinder pressure is supplied to the wheel cylinder via the antilock brake opening / closing valve. , Anti-lock brake control becomes possible.
When the brake pedal is not depressed, the master cylinder is connected to the wheel cylinder via the pump and the anti-lock brake opening / closing valve, so when the pump is rotated, pressure is supplied to the wheel cylinder even if the brake is not depressed. It becomes possible to perform traction control.

Further, the hydraulic control device disclosed in Japanese Patent Laid-Open No. 63-110064 has an on-off valve between a reservoir tank and a master cylinder, and a relief valve for shutting off the reservoir tank from the suction port of the pump. Is equipped with. The on-off valve is closed during drive slip control. At this time, when the pump is rotated, oil is sent from the reservoir tank to the anti-lock brake opening / closing valve via the relief valve, so that the wheels can be braked by opening / closing the anti-lock brake opening / closing valve without pressing the brake pedal. become.

Normally, in a vehicle, the front left wheel, the front right wheel,
It has four wheels, a rear left wheel and a rear right wheel, and a wheel cylinder is provided for each wheel. The master cylinder has two pressure chambers
It has a chamber and supplies pressure to the system of the front left wheel and the front right wheel, the system of the rear left wheel and the rear right wheel, or the system of the front left wheel and the rear right wheel and the system of the rear left wheel and the front right wheel, respectively.

[0005]

However, the above-described wheel braking force control device, when performing traction control, automatic brake control, or the like, has an antilock brake circuit as the number of antilock brake circuits to be controlled increases. The number of on-off valves provided between the reservoirs increases, and the cost increases accordingly.

In order to control two or more wheel cylinders, it is necessary to use a pump to pressurize each system. Normally, in the reflux type anti-lock brake circuit, the pump returns the oil accumulated in the discharge passage to the pressure chamber, so that high suction performance is not required. However, high suction performance is required to suck oil from the reservoir tank. A pump having such a high suction performance is expensive. Therefore, in order to pressurize the wheel cylinders of two or more systems, it is necessary to equip each system with a pump having high suction performance, and the system as a whole must be expensive.

Therefore, in the present invention, it is an object of the present invention to make it possible to control the pressure of two or more wheel cylinders in accordance with the depression of the brake pedal, to control the pressure independently of the depression of the brake pedal, and to reduce the cost. To do.

Another object of the present invention is to allow the brake pedal to be depressed and to increase the pressure in the wheel cylinder above the pressure generated by the brake pedal, and to improve the pedal feeling of the brake.

[0009]

In order to solve the above-mentioned problems, in the invention according to claim 1, a first piston, a second piston, and a first piston which move in response to depression of a brake pedal. Reservoir chamber formed on the brake pedal side of which the volume changes with the movement of the first piston, a first pressure chamber defined by the first piston and the second piston, and the brake pedal of the second piston A second pressure chamber formed on the side opposite to the first pressure chamber, a fifth passage communicating with the reservoir chamber, a first passage communicating the first pressure chamber with the reservoir or the fifth passage, and A second passage communicating with the first pressure chamber, and a third passage and a fourth passage communicating with the second pressure chamber, wherein the first piston is connected to the first passage and the first passage when the brake pedal is depressed. Pressure chamber Wherein while blocking communication between the second
A master cylinder having a piston that blocks communication between the third passage and the second pressure chamber; a reservoir tank that communicates with the third passage; and a piston interposed between the second passage and the first wheel cylinder. A discharge passage for discharging the hydraulic pressure of the first wheel cylinder, the discharge passage and the second passage
The second passage is arranged between the passages and pumps up the oil in the discharge passage.
A first hydraulic control circuit for adjusting the hydraulic pressure generated in the second passage to give the hydraulic pressure to the first wheel cylinder; and an interposing between the fourth passage and the second wheel cylinder. A second hydraulic pressure control circuit for adjusting the hydraulic pressure generated in the fourth passage and giving the hydraulic pressure to the second wheel cylinder; and the fifth passage, the reservoir tank,
And a switching valve that is interposed between the discharge passage and switches between communication between the reservoir tank and the fifth passage and communication between the reservoir tank and the discharge passage.

According to the invention of claim 1, four wheels can be provided by providing two first wheel cylinders and two second wheel cylinders. Further, if two each of the first hydraulic control circuit and the second hydraulic control circuit are prepared and the pressures of the four wheel cylinders are controlled separately, the braking force can be controlled independently for the four wheels.

In the first aspect of the invention, a first reservoir capable of accumulating oil may be arranged in the first discharge passage.

In the invention of claim 1, the switching valve may be composed of two on-off valves which are alternately switched.

According to the first aspect of the invention, the master cylinder is provided with the first pressure chamber and the second pressure chamber, and the first pressure chamber and the second pressure chamber are provided in the master cylinder.
And the second hydraulic pressure control circuit is provided to form two systems, but a further pressure chamber that increases the pressure according to the pressure of the first pressure chamber or the second pressure chamber is provided so as to correspond to three or more brake systems. May be.

Further, preferably, as described in claim 2, between the reservoir tank and the fifth passage, the reservoir tank is connected to the fifth passage.
It is advisable to provide a one-way valve that allows only passage to the passage.

[0015]

In the invention of claim 1, when the switching valve connects the reservoir tank and the fifth passage, the reservoir tank and the first passage of the master cylinder communicate with each other. In this state,
The first and second pressure chambers of the master cylinder are filled with oil from the reservoir tank. Here, when the brake pedal is depressed, the first piston blocks the communication between the first passage and the first pressure chamber and the second piston communicates between the third passage and the second pressure chamber in the master cylinder. Shut off. Therefore, the internal pressure of each of the first pressure chamber and the second pressure chamber increases according to the amount of depression of the brake pedal.

The first hydraulic control circuit is connected to the first hydraulic pressure control circuit via the second passage.
Since it communicates with the pressure chamber, the braking force is generated in the wheel controlled by the first wheel cylinder by applying the pressure of the first pressure chamber to the first wheel cylinder. If the pressure of the first wheel cylinder is released to the discharge passage, the braking force of the first wheel cylinder can be weakened. Therefore, if the first hydraulic pressure control circuit adjusts the pressure of the first pressure chamber and applies it to the first wheel cylinder, the braking force can be adjusted. For example, slipping of the wheels can be prevented by weakening the braking force when the wheels slip. The oil in the discharge passage can be returned to the second passage by turning the pump.

The second hydraulic control circuit is connected to the second hydraulic pressure control circuit via the fourth passage.
Since it communicates with the pressure chamber, the braking force is generated in the wheel controlled by the second wheel cylinder by applying the pressure of the second pressure chamber to the second wheel cylinder. If the second hydraulic pressure control circuit adjusts the pressure in the second pressure chamber and applies it to the second wheel cylinder, the braking force can be adjusted. For example,
Wheel slip can be prevented by weakening the braking force when the wheels slip.

In the first aspect of the present invention, when the reservoir tank and the discharge passage of the first hydraulic control circuit are communicated with each other, the reservoir tank and the first passage of the master cylinder are shut off from each other.
Here, when the pump is rotated, oil is expelled from the reservoir tank to the second passage and the first pressure chamber via the pump. At this time, since the first pressure chamber and the reservoir tank are shut off from each other, the pressure in the second passage and the first pressure chamber rises.

The first hydraulic control circuit is connected to the first hydraulic pressure control circuit via the second passage.
Since it communicates with the pressure chamber, the braking force is generated in the wheel controlled by the first wheel cylinder by applying the pressure of the first pressure chamber to the first wheel cylinder. If the first hydraulic control circuit adjusts the pressure in the first pressure chamber and applies it to the first wheel cylinder, the braking force can be adjusted. For example,
Wheel slip can be prevented by applying a braking force when the wheels slip during acceleration. If an obstacle in front is detected and braking force is applied, automatic braking can be configured. Furthermore,
Even when it is desired to apply the braking force at a pressure higher than the master cylinder pressure due to the depression of the brake pedal, if the pump is rotated, the braking force can be exerted at a pressure higher than the master cylinder pressure obtained by the depression of the brake pedal.

On the other hand, in response to the increase in the pressure in the first pressure chamber, the second piston moves to interrupt the gap between the second pressure chamber and the reservoir tank to increase the pressure in the second pressure chamber.

The second hydraulic control circuit is connected to the second hydraulic pressure control circuit via the fourth passage.
Since it communicates with the pressure chamber, the braking force is generated in the wheel controlled by the second wheel cylinder by applying the pressure of the second pressure chamber to the second wheel cylinder. If the second hydraulic pressure control circuit adjusts the pressure in the second pressure chamber and applies it to the second wheel cylinder, the braking force can be adjusted. Therefore,
The same control as that of the first wheel cylinder can be performed for the second wheel cylinder.

The reservoir chamber is closed when the brake pedal is depressed when the reservoir tank and the discharge passage of the first hydraulic control circuit communicate with each other and the pump rotates to increase the hydraulic pressure in the second passage. It Therefore, the brake pedal is fixed.

According to another aspect of the present invention, when the reservoir tank and the discharge passage of the first hydraulic control circuit are communicated with each other and the pump is rotated to increase the hydraulic pressure of the second passage, the brake pedal is depressed. Oil flows from the directional valve into the reservoir chamber,
The first piston slides. Therefore, even when a predetermined braking force is exerted by traction or automatic braking without depending on the driver's intention, it is possible to exert more braking force by the driver's intention.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a hydraulic circuit diagram of an embodiment of the present invention. Here, the brake pedal 22 is the master cylinder 1
It is connected to 0. First wheel cylinders 38, 39 are arranged on the two wheels 42, 43 of the vehicle, respectively. Second wheel cylinders 40 and 41 are arranged on two wheels 44 and 45 of the vehicle, respectively. The wheel cylinders 38-41 adjust the braking force of the wheels 42-45, respectively. Wheel speed sensors 46 to 49 for detecting the rotation speeds of the respective wheels are arranged close to the wheels 42 to 45. The master cylinder 10 is a tandem master cylinder, and includes a reservoir chamber 13, a first pressure chamber 11, and a second pressure chamber 11.
The pressure chamber 12 and the first passage 16 communicating with the first pressure chamber 11
And the second passage 17, the third passage 18 and the fourth passage 19 that communicate with the second pressure chamber 12, and the fifth passage that communicates with the reservoir chamber.
A passage 20; a first piston 14 that moves in the first pressure chamber 11 in conjunction with depression of a brake pedal 22;
The second piston 15 moves in the second pressure chamber 12 according to the pressure of the pressure chamber 11, and the first piston 14 is provided between the first passage 16 and the first pressure chamber 11 when the brake pedal 22 is depressed. The second piston 15 blocks the communication between the third passage 18 and the second pressure chamber 12 while blocking the communication. The reservoir chamber 13 includes the brake pedal 2 of the first piston 14.
It is formed on the second side. The first pressure chamber 11 is the first piston 1
It is divided by 4 and the second piston 15. The second pressure chamber 12 is formed on the side of the second piston 15 opposite to the brake pedal 22. The reservoir tank 21 has a passage 2
4 communicates with the third passage 18 of the master cylinder 10. The switching valve 26 is a solenoid valve and is operated by the operation of the solenoid 89. The switching valve 26 communicates with the first passage 16 of the master cylinder 10 via the passage 25, and also communicates with the reservoir tank 21 via the passage 23.
A relief valve 71 and a one-way valve 73 are provided in parallel with the switching valve 26 between the passage 23 and the passage 25. The one-way valve 73 allows only the flow of oil from the passage 23 to the passage 25. The relief valve 71 opens when the pressure in the passage 25 rises above a predetermined pressure. An orifice 72 is provided in parallel with the relief valve. The first hydraulic pressure control circuit 27 is interposed between a passage 29 communicating with the second passage 17 of the master cylinder 10 and passages 34, 35 communicating with the first wheel cylinders 38, 39, and the hydraulic pressure generated in the second passage 17 is generated. Is adjusted and given to the first wheel cylinders 38, 39. The pump 50 is equipped with a check valve that allows oil to flow only from the downstream side to the upstream side, and is driven by the electric motor 33 to expel oil. This pump 5
No. 0 has a discharge port communicating with the second passage 17 through a passage 29, and a suction port communicating with the switching valve 26 through a passage 31. The switching valve 26 is switched to select either communication between the passage 23 and the passage 31 or communication between the passage 23 and the passage 25. The switching valve 26 is biased by a spring so that communication between the passage 23 and the passage 25 is selected when the solenoid 89 is not energized (OFF), and the passage 23 and the passage 31 are connected when the solenoid 89 is energized (ON). Communication between them is selected. The second hydraulic control circuit 28 is interposed between a passage 30 communicating with the fourth passage 19 of the master cylinder 10 and passages 36, 37 communicating with the second wheel cylinders 40, 41.
The hydraulic pressure generated in the fourth passage 19 is adjusted and given to the second wheel cylinders 40 and 41. The control means is the electronic control circuit 7
0, and controls switching of the switching valve 26.

The first hydraulic control circuit 27 includes a first opening / closing valve 5 which is an inlet valve with two ports and two positions for each wheel.
2, 53 and second on-off valves 56 and 57 which are 2-port 2-position outlet valves, each of which is a solenoid 60, 61, 64 controlled by an electronic control circuit 70.
Each of them is switched by 65. The first on-off valves 52 and 53 are opened when the solenoids 60 and 61 are off, and the second on-off valves 56 and 57 are the solenoids 64 and 6.
It is closed with 5 turned off.

The input ports of the first on-off valves 52 and 53 are connected to a passage 29 communicating with the second passage 17 of the master cylinder 10, and the output ports thereof are respectively wheel cylinders 3.
It is connected to 8,39. The input ports of the second on-off valves 56 and 57 are connected to the wheel cylinders 38 and 39, respectively, and the output ports thereof are connected to the reservoir 68 and the suction port of the pump 50 via the discharge passage 31.

The second hydraulic control circuit 28 includes a third opening / closing valve 5 which is an inlet valve having two ports and two positions for each wheel.
4, 55 and fourth on-off valves 58, 59, which are 2-port 2-position outlet valves, each of which is a solenoid 62, 63, 66 controlled by an electronic control circuit 70.
Each of them is switched by 67. The third on-off valves 54 and 55 are opened when the solenoids 62 and 63 are off, and the fourth on-off valves 58 and 59 are the solenoids 66 and 6.
It is closed with 7 turned off.

The input ports of the third on-off valves 54 and 55 are connected to the passage 30 which communicates with the fourth passage 19 of the master cylinder 10, and the output ports thereof are the wheel cylinders 4 respectively.
It is connected to 0 and 41. The input ports of the fourth on-off valves 58 and 59 are connected to the wheel cylinders 40 and 41, respectively, and the output ports thereof are connected to the reservoir 69 and the suction port of the pump 51 via the discharge passage 32. Pump 51 is pump 50
It is driven by the rotation of the motor 33 in the same manner as.

In order to prevent the occurrence of abnormally high pressure in the closed circuit between the discharge port of the pump 50 and the switching valve 26, a relief valve 71 is provided in this embodiment. As a result, when an abnormally high pressure is generated, the relief valve 71 opens and the pressure is released. Further, at this time, since the flow of oil is suppressed by the orifice 72, it is possible to suppress the generation of bubbles due to a sharp decrease in pressure. Instead of the relief valve 71, the driving of the motor 33 may be stopped when an abnormally high pressure is generated. Also,
A relief valve may be provided between the discharge side and the suction side of the pump 50.

Since the pump 50 needs to suck the oil from the reservoir tank 21, it is preferable to use a self-contained pump having a good suction property. On the other hand, since the pump 51 may have a poor suction property, an inexpensive pump can be used.

FIG. 2 is a block diagram showing the configuration of the electronic control circuit 70. Wheel speed sensor 46 provided on each wheel
The output signal detected by 49 is the input interface 75-
It is input to the microcomputer 74 via 78.
Then, a control signal is output from the microcomputer 74 to the motor 33 via the output interface 79, and a control signal is output to each solenoid via the output interfaces 80 to 88.

The control of the hydraulic pressure control device performed by the microcomputer 74 will be described with reference to the flowchart of FIG. When the power of the microcomputer 74 is turned on, the following processing starts. First, in step 90, the microcomputer 74 is initialized, and in step 91, the rotation speed of each wheel is calculated by receiving the outputs from the wheel speed sensors 46 to 49. Next, the routine proceeds to step 92, where normal brake (normal), anti-lock brake control (ABS), traction control control (TRC), braking force distribution control during braking, braking force during non-braking are determined based on the wheel speed and slip ratio. Either one of the distribution control and the automatic braking control is selected.

The antilock brake control is for preventing the wheels from being locked during braking. The anti-lock brake control mode is selected when the wheels slip during deceleration of the vehicle. For example, the antilock brake control mode is selected when the wheel speed deviates from the vehicle speed by a predetermined width or more. The vehicle body speed may be estimated and obtained from the average or maximum value of the wheel speeds of the four wheels, or a sensor for measuring the vehicle body speed may be provided separately. The braking force distribution control adjusts the braking force of the left and right wheels to improve the turning performance of the vehicle and prevent the vehicle from spinning. The braking force distribution mode during braking is selected when the yaw rate of the vehicle increases during braking. The braking force distribution mode during non-braking is selected when the turning amount of the vehicle increases during non-braking. The turning amount may be detected by disposing a yaw rate sensor, or the steering amount of the steering wheel may be detected. Traction control prevents wheel slip during acceleration. The traction control mode is selected when the wheel speed deviates from the vehicle body speed by a predetermined width or more. Automatic braking
The brake is applied regardless of the direct operation of the driver. The automatic braking mode is selected, for example, when there is an obstacle in front of the vehicle or when the driver is asleep. The obstacle may be detected by an obstacle sensor such as a radar. The snooze detection may be performed by detecting the heart rate of the driver with a heartbeat sensor, detecting the brain waves of the driver with an electroencephalogram sensor, or confirming the number of blinks and the movement of the pupil with a camera. In the automatic braking mode, for example, a predetermined operation is performed such that braking is performed when blinks are performed three times in a row, and the driver utters "Brake" or the movement of the mouth is detected to apply braking. It may be selected by a person who has made such a decision. When the above mode is not selected, the normal mode is set.

When the normal brake is selected in step 92, the solenoid 89 of the switching valve 26 is selected in step 97.
Is turned off, and all solenoids are turned off in step 98. As a result, the reservoir tank 21 and the first passage 1
6, the first pressure chamber 11 and the wheel cylinder 38,
39 communicates with each other, and the second pressure chamber 12 and the wheel cylinder 4
0, 41 communicate. At this time, when the brake pedal 22 is depressed, the wheel cylinder 38,
39 and from the second pressure chamber 12 to the wheel cylinder 4
Brake fluid pressure is supplied to 0 and 41 to perform braking.

When antilock brake control (ABS) is selected in step 92, the solenoid 89 of the switching valve 26 is turned off in step 93, and antilock brake control is performed in step 94. Here, the wheel cylinder is pressure-increase, pressure-retaining, and pressure-reducing according to the wheel lock state, and the braking force is adjusted to adjust the slip state between the wheel and the road surface. During depressurization, the solenoids 60 to 67 of the wheels to be depressurized are turned on. As a result, the brake fluid is discharged from the wheel cylinder of the wheel whose pressure is to be reduced to the reservoir 68 or 69 through the discharge passage 31 or 32, the pressure of the corresponding wheel cylinder is reduced, and the braking force is weakened. When holding, turn on the solenoids 60 to 63 of the corresponding wheels,
The solenoids 64-67 are turned off. This closes the wheel cylinder of the wheel to be held and holds the pressure. When boosting pressure, solenoids 60 to 67 of wheels to be boosted
To turn off. As a result, the brake fluid pressure is supplied from the first pressure chamber 11 or the second pressure chamber 12 to the wheel cylinder of the wheel to be increased in pressure, the corresponding wheel cylinder is increased in pressure, and the braking force is strengthened. The liquids stored in the reservoirs 68 and 69 are returned to the first pressure chamber 11 and the second pressure chamber 12 by driving the pumps 50 and 51, respectively.

When traction control (TRC) is selected in step 92, the solenoid 89 of the switching valve 26 is turned on in step 101, and traction control is performed in step 102. Here, the pump 50 is driven to draw oil from the reservoir tank 21 through the discharge passage 31 to increase the hydraulic pressure in the passage 29 and the first pressure chamber 11. When the pressure in the first pressure chamber 11 increases, the second piston 15 moves, the third passage 18 is closed, and the second pressure chamber 1
The pressure inside 2 also increases. Here, pressure increase, pressure retention, and pressure reduction are performed so as to apply an optimum braking force to the slipped wheel. When boosting pressure, solenoids 60 to 67 of wheels to be boosted
To turn off. As a result, the brake fluid pressure is supplied from the first pressure chamber 11 or the second pressure chamber 12 to the wheel cylinder of the wheel whose pressure is to be increased, the pressure is increased, and the braking force is applied to the wheel.
At this time, the solenoids 60 to 63 of the wheels other than the wheel to be boosted (driven wheel or non-slip wheel) are turned on,
Prevent hydraulic pressure from working on the wheel cylinders. At the time of holding, the solenoids 60 to 63 of the corresponding wheels are turned on and the solenoids 64 to 67 are turned off. This closes the wheel cylinder of the wheel to be held and holds the pressure. When decompressing, the solenoid 60 of the wheel to be decompressed
Turn on 67. As a result, on the side of the first wheel cylinders 38, 39, the brake fluid pressure inside is sucked by the pump 50 or discharged to the reservoir tank 21 or the reservoir 68. In addition, the second wheel cylinder 40,
On the 41 side, the internal brake fluid pressure is sucked by the pump 51 or discharged to the reservoir 69. Therefore, the brake fluid pressure in the corresponding wheel cylinders 38 to 41 is reduced, and the braking force is weakened.

When automatic braking is selected in step 92, the solenoid 89 of the switching valve 26 is turned on in step 103, and automatic braking control is performed in step 104. Here, the pump 50 is driven to drive the reservoir tank 21.
Oil is pumped through the discharge passage 31 to increase the hydraulic pressure in the passage 29 and the first pressure chamber 11. When the pressure in the first pressure chamber 11 increases, the second piston 15 moves and the third passage 1
8 is closed and the pressure in the second pressure chamber 12 also increases. Next, the solenoids 60 to 67 are appropriately turned on / off to adjust the pressure in the wheel cylinder. To adjust the braking force, the first opening / closing valve 5
2, 53, third on-off valves 54, 55, second on-off valves 56, 5
The seventh and fourth open / close valves 58 and 59 may be opened / closed, or the rotation amount of the motor 33 may be adjusted.

When the braking force distribution control during braking is selected in step 92, the solenoid 89 of the switching valve 26 is turned off in step 95, and the braking force distribution control during braking is performed in step 96. Here, the solenoids 60 to 67 are appropriately turned on, the pressure in the wheel cylinder is reduced for each wheel, and the distribution of the braking force to the left and right wheels is controlled.

When the braking force distribution control during non-braking is selected in step 92, the solenoid 89 of the switching valve 26 is turned on in step 99, and the braking force distribution control during non-braking is performed in step 100. Here, the pump 50 is driven to draw oil from the reservoir tank 21 through the discharge passage 31 to increase the hydraulic pressure in the passage 29 and the first pressure chamber 11. First
When the pressure in the pressure chamber 11 increases, the second piston 15 moves, the third passage 18 is closed, and the pressure in the second pressure chamber 12 also increases. Next, turn on the solenoids 60 to 67 as appropriate.
Turn off and adjust the pressure in the wheel cylinder. In order to adjust the braking force, the first opening / closing valves 52, 53, the third opening / closing valves 54, 55, the second opening / closing valves 56, 57 and the fourth opening / closing valves 58, 59 may be opened / closed as in the case of the traction control. However, the rotation amount of the motor 33 may be adjusted.

When any of the above controls is completed, the process returns to step 91.

As described above, normal brake, anti-lock brake control, braking force distribution control, traction control, and automatic brake control are possible. Although a plurality of control modes are provided in the above embodiment, it is not necessary to have all modes in an actual vehicle, and some of them may be selected and installed.

In the above embodiment, the first pump 50 and the second pump 51 are driven by one motor 33, but two independent motors may be provided and controlled independently.

In the above embodiment, the first hydraulic control circuit 2
7 is provided with the reservoir 68, but when the second opening / closing valves 56 and 57 are open, if the pump 50 is rotated,
Since the oil discharged from the wheel cylinders 38 and 39 is returned to the second passage 17, the reservoir 68 may be omitted.

In the above embodiment, the brake pedal 2
Although 2 is configured to directly move the first piston 14, a booster or the like may be interposed between the first piston 14 and the brake pedal 22.

Normally, in FF vehicles and FR vehicles, traction control is performed only for the two left and right driving wheels. In the above embodiment, when the wheels 42 and 44 are on the front wheel side and the wheels 43 and 45 are on the rear wheel side and X piping is used, pressurizing one system can also pressurize the other system. Is controllable and becomes particularly effective.

In the above embodiment, the first hydraulic control circuit 2
The seventh and second hydraulic control circuits 28 are not limited to this form. For example, a throttle valve may be used instead of the first opening / closing valve and the third opening / closing valve, or a throttle valve instead of the second opening / closing valve and the fourth opening / closing valve. Or using a 3-port 2-position valve by combining the first on-off valve and the second on-off valve and the third on-off valve and the fourth on-off valve. Any form may be used as long as it can be adjusted between the pressures of the passage 31 and the passage 32.

Further, in the above embodiment, the pump 51 may be omitted. In this case, the amount of oil that can be depressurized when depressurizing the wheel cylinders 40 and 41 is the reservoir 69.
However, it can be controlled without the pump 51 and the cost is low.

In the above embodiment, the reservoir tank 2
1 communicates with the discharge passage 31 of the first hydraulic control circuit 27,
When the brake pedal 22 is depressed when the pump 50 rotates and the hydraulic pressure in the second passage 17 increases, the reservoir chamber 13 is closed as long as the internal pressure does not exceed the pressure determined by the relief valve 71. . Therefore, the brake pedal 2
No. 2 does not get pushed back even if the pressure is increased by the pump 50, and the pedal feeling is good.

In the above embodiment, the reservoir tank 2
1 communicates with the discharge passage 31 of the first hydraulic control circuit 27,
When the brake pedal 22 is depressed while the pump 50 is rotating and the hydraulic pressure in the second passage 17 is increasing, the one-way valve 7
Oil flows into the reservoir chamber 13 from the first piston 1
4 slides. Therefore, even when a predetermined braking force is exerted by traction or automatic braking without depending on the driver's intention, it is possible to exert more braking force by the driver's intention.

[0051]

According to the first aspect of the present invention, in the hydraulic control device, the system of the second hydraulic control circuit can be pressurized by pressurizing the system of the first hydraulic control circuit. Therefore, the cost of the hydraulic control device can be reduced and the structure can be simplified.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of a hydraulic control device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an electronic control circuit according to an embodiment of the present invention.

FIG. 3 is a flowchart of the microcomputer according to the embodiment of the present invention.

[Explanation of symbols]

10 master cylinder 11 1st pressure chamber 12 2nd pressure chamber 13 reservoir chamber 14 1st piston 15 2nd piston 16 1st passage 17 2nd passage 18 3rd passage 19 4th passage 20 5th passage 21 reservoir tank 22 brake pedal 23, 24, 25, 29, 30, 34, 35, 36, 3
7 passage 26 switching valve 27 1st hydraulic control circuit 28 2nd hydraulic control circuit 31, 32 discharge passage 33 electric motor 38, 39 first wheel cylinder 40, 41 second wheel cylinder 42-45 wheel 46-49 wheel speed sensor 50 , 51 Pump 52, 53 First opening / closing valve 54, 55 Third opening / closing valve 56, 57 Second opening / closing valve 58, 59 Fourth opening / closing valve 60 to 67, 89 Solenoid 68, 69 Reservoir 70 Electronic control circuit 71 Relief valve 72 Orifice 73 one-way valve 74 microcomputer 75-78 input interface 79-88 output interface

Claims (2)

[Claims] 1. A first piston that moves in response to depression of a brake pedal, a second piston, and a reservoir chamber that is formed on the brake pedal side of the first piston and whose volume changes with the movement of the first piston. And a first pressure chamber defined by the first piston and the second piston, a second pressure chamber formed on a side of the second piston opposite to the brake pedal, and the reservoir chamber communicating with each other. A fifth passage, a first passage that communicates the first pressure chamber with the reservoir chamber or the fifth passage, a second passage that communicates with the first pressure chamber, and a second passage that communicates with the second pressure chamber A third passage and a fourth passage, wherein when the brake pedal is depressed, the first piston blocks communication between the first passage and the first pressure chamber, and the second piston forms the third passage. The second pressure A master cylinder that blocks communication between the force chambers; a reservoir tank that communicates with the third passage;
A discharge passage that is interposed between the second passage and the first wheel cylinder and discharges the hydraulic pressure of the first wheel cylinder, and the discharge passage that is disposed between the discharge passage and the second passage. A pump for pumping oil to increase the oil pressure in the second passage, and adjusting the oil pressure generated in the second passage to give it to the first wheel cylinder; the fourth passage and the second wheel A second hydraulic pressure control circuit interposed between the cylinders and adjusting the hydraulic pressure generated in the fourth passage to give it to the second wheel cylinder; and between the fifth passage, the reservoir tank, and the discharge passage. A fluid pressure control device comprising: a switching valve that is interposed and switches between communication between the reservoir tank and the fifth passage and communication between the reservoir tank and the discharge passage. 2. The method according to claim 1, wherein the reservoir tank and the fifth passage are connected to each other from the reservoir tank to the fifth passage.
A fluid pressure control device comprising a one-way valve which allows only passage to a passage.