JPH07251729A - Brake control device - Google Patents

Abstract

PURPOSE:To secure correspondense to requirement of high pump discharge pressure and also improve reduction of demand and fuel consumption in a brake control device having an oil pump by actuator drive. CONSTITUTION:A pump discharge pressure control means g for switching pump discharge pressure controlling from an oil pump d from a low pressure area control mode to a high pressure area control mode only when a brake condition requiring pump discharge pressure more than that of a low pressure area is detected by a brake state detecting means f.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake control device for arbitrarily controlling the brake fluid pressure applied to each wheel.

[0002]

2. Description of the Related Art Conventionally, as a brake control device, for example, one described in JP-A-4-87867 is known.

In the above-mentioned conventional source, there is a device for controlling the brake pressure supplied to the wheel cylinder at the time of a braking operation or the brake TCS by an electronic hydraulic control valve for adjusting the hydraulic pressure according to the master cylinder pressure or the secondary external hydraulic pressure. Is shown.

That is, the electronic hydraulic control valve is provided in the middle of the external hydraulic pressure source and the wheel cylinder, and the force from the proportional solenoid that pushes to the pressure reducing side according to the current value and the master cylinder pressure or the secondary external hydraulic pressure. This is a valve structure having a spool on which a force from a plunger that pushes the pressure increasing side in accordance with the pressure acts, and an external hydraulic pressure supplied from an external hydraulic pressure source is set to 2
The control pressure is adjusted according to the difference between the two inputs.

[0005]

However, in the above-mentioned conventional brake control device, it is usually sufficient that the wheel cylinder pressure is about 80 kgf / cm ^{2 at} maximum, and the pump discharge pressure is higher than this. Value (eg 10
It may be 0 to 150 kgf / cm ² ). However, when the brake pads become hot and the wheel cylinder pressure is maintained, the braking force decreases, or when the vehicle brakes suddenly during overloading, which requires a large wheel cylinder pressure to resist the vehicle inertia. In consideration of the rarely occurring braking state, the wheel cylinder pressure needs to be about 140 kgf / cm ^{2 at} maximum, and the pump discharge pressure is, for example, 150 to 20.
It is necessary to apply high pressure such as 0 kgf / cm ² .

If the pump is constantly operated at such a high pressure, in the case of a pump driven by an electric motor, current consumption will increase significantly. Further, in the case of a pump driven by an engine, a large engine load causes a reduction in fuel consumption.

The present invention has been made in view of the above problems. A first object of the present invention is to provide a brake control device having an oil pump driven by an actuator as an external hydraulic pressure source, which requires a high pump discharge pressure. It is intended to reduce the current consumption and improve the fuel consumption while ensuring the compatibility.

The second object is to meet the demand for high pump discharge pressure when the master cylinder pressure or wheel cylinder pressure is high, when the braking deceleration is high decelerating, when the braking force is high, or when the fade condition occurs. The answer is to reduce current consumption and improve fuel efficiency.

A third object is to obtain a low pressure region control mode and a high pressure region control mode by pump discharge pressure control by a simple selection command in addition to the first or second object.

[0010]

In order to achieve the first object, in the brake control device of the first invention, as shown in the claim correspondence diagram of FIG. 1, a master cylinder pressure is generated according to the brake operating force. Master cylinder a, a wheel cylinder b provided in a braking device for each wheel and operated by control pressure, an oil pump d that generates hydraulic pressure by a drive actuator c regardless of brake operation, and a master cylinder pressure. An electronic hydraulic control valve e that receives a signal pressure, a force generated by the signal pressure, and a force generated by a solenoid, and adjusts the external hydraulic pressure supplied from the external hydraulic pressure source to a control pressure according to the difference between the two inputs. , A braking state detecting means f for detecting a braking state, an oil pump as an external hydraulic pressure source capable of discharging the pump discharge pressure in the low pressure range and the pump discharge pressure in the high pressure range, and the pump. The discharge pressure control means is provided with pump discharge pressure control means g for inputting the detection signal from the braking state detecting means and switching the oil pump discharge pressure between a low pressure range control mode and a high pressure range control mode. It is characterized by

In order to achieve the above-mentioned second object, in the brake control device of the second invention, in the brake control device according to claim 1, the braking state detecting means is a pressure for detecting the master cylinder pressure or the wheel cylinder pressure. Detection means,
At least one of deceleration detecting means for detecting the deceleration in the front-rear direction of the vehicle, braking force detecting means for detecting the braking force, or temperature detecting means for detecting the temperature of the rotor or the brake caliper is provided, The pump discharge pressure control means g is: When the pressure detection value of the pressure detection means exceeds a certain threshold value When the deceleration detection value of the deceleration detection means exceeds a certain threshold value Braking force detection means When the braking force detection value of exceeds a certain threshold value ・ When it is determined that the temperature detection value of the temperature detection means has reached the fade state region When one of the above conditions is satisfied, the low pressure region control is performed. It is characterized in that it is a means for switching from the mode to the high pressure range control mode.

In order to achieve the above-mentioned third object, in the brake control device of the third invention, as shown in the claim correspondence diagram of FIG. 1, in the brake control device according to claim 1 or 2, the oil pump A pump discharge pressure control mode selection means h capable of selecting the pump discharge pressure from d in a low pressure range control mode and a high pressure range control mode is provided, and the pump discharge pressure control means g requires a pump discharge pressure above the low pressure range. The means for outputting a selection command for switching from the low pressure range control mode to the high pressure range control mode to the pump discharge pressure control mode selection means h only when a braking state to be detected is detected.

[0013]

The operation of the first invention will be described.

During braking accompanied by a brake operation, in the master cylinder a, a master cylinder pressure corresponding to the brake operation force is generated, and this master cylinder pressure is applied to the hydraulic control valve d.
To the signal pressure. Therefore, when the pump discharge pressure from the oil pump d is supplied to the supply pressure port of the electronic hydraulic control valve e, the electronic hydraulic control valve e is controlled according to the difference between the force generated by the master cylinder pressure and the force generated by the solenoid. The pressure is adjusted to a pressure, and the control pressure is supplied to the wheel cylinder b to apply a braking force to each wheel.

During this braking, the low pressure range control mode is normally selected as the pump discharge pressure control, but when the braking state detecting means f detects a braking state requiring a pump discharge pressure above the low pressure range. In the pump discharge pressure control means g, control for switching the pump discharge pressure control from the oil pump d from the low pressure range control mode to the high pressure range control mode is performed.

Therefore, when the pump discharge pressure due to a high pressure is required, the high pressure range control mode is selected to ensure compatibility with the high pressure requirement.
The selection of the high pressure range control mode is set to the minimum necessary to detect the braking state requiring the pump discharge pressure in the low range or higher, so that the consumption current can be reduced in the case of the oil pump d driven by the electric motor. In the case of the oil pump d driven by the engine, the fuel consumption is improved.

The operation of the second invention will be described.

During braking, the braking state detecting means f detects the master cylinder pressure or wheel cylinder pressure, deceleration, braking force, rotor temperature, and brake caliper pad temperature to determine the master cylinder pressure or wheel cylinder pressure. When this pressure detection value exceeds a certain threshold value, the deceleration is detected.When this deceleration detection value exceeds a certain threshold value, the braking force is detected. When the temperature exceeds the threshold value When the rotor temperature or the pad temperature of the brake caliper is detected and it is determined that the detected temperature value has reached the fade condition range, any one of the above conditions (1) to (4) is satisfied. ,
In the pump discharge pressure control means g, control for switching the pump discharge pressure control from the oil pump d from the low pressure range control mode to the high pressure range control mode is performed.

Therefore, when the master cylinder pressure or the wheel cylinder pressure is high, the braking deceleration is high decelerating, the braking force is high, or the fade state is satisfied, the consumption current is reduced while meeting the high pump discharge pressure request. And fuel efficiency can be improved.

The operation of the third invention will be described.

Between the pump discharge pressure control means g and the drive actuator c, there is provided pump discharge pressure control mode selection means h capable of selecting the pump discharge pressure from the oil pump d in the low pressure range control mode and the high pressure range control mode. It is provided.
Therefore, when a braking state requiring a pump discharge pressure above the low pressure range is detected during braking, the pump discharge pressure control means g causes the pump discharge pressure control mode selection means h to change from the low pressure range control mode to the high pressure range control mode. A selection command to switch to is output.

Therefore, compared to the case of the discharge pressure control by the variable drive control for the drive actuator c, the low pressure region control mode and the high pressure region control mode can be obtained by a simple ON / OFF selection command.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

First, the structure will be described.

FIG. 2 is an overall system diagram showing the brake control device of the embodiment of the present invention.

First, the main structure will be described. In FIG. 2, 1 is a master cylinder, 2 is a wheel cylinder, 3 is an oil pump, 4 is a main valve, 5 is a pilot valve, 6 is a TCS switching valve, and 7 is a pressure reducing valve. Valve, 8 is a switching valve for leak reduction,
Reference numeral 9 is a pilot switching valve, 10 is a check valve, 11 is a fail valve, and 12 is a controller.

The master cylinder 1 generates a master cylinder pressure according to the brake operating force applied to the brake pedal.

The wheel cylinder 2 is provided in the braking device for each wheel, and operates under the control pressure created in the main valve 4 when normal, and when the master cylinder 1 fails.
It operates by the master cylinder pressure from.

The oil pump 3 has an electric motor 13
It is driven by (corresponding to the drive actuator c), and a low pressure region control mode (for example, 10
0 to 150 kgf / cm ² ) and high pressure range control mode (for example, 1
The discharge pressure is controlled according to the control mode selected from the two control modes of 50 to 200 kgf / cm ² ).

The main valve 4 inputs the force in the left direction (pressure increasing direction) in the drawing generated by the pilot pressure from the pilot valve 5 and the force in the right direction (pressure decreasing direction) in the drawing generated by the solenoid 4a, and the oil pump 3 The pump discharge pressure supplied from is adjusted to the control pressure according to the difference between the two inputs.
Incidentally, I is a supply pressure port, J is a control pressure port, and K is a drain port.

The pilot valve 5 uses the master cylinder pressure introduced from the master cylinder pressure port O or the secondary pump discharge pressure introduced from the secondary pump discharge pressure port N as a signal pressure, and the pump discharge pressure from the oil pump 3 as a signal pressure. Adjust the pilot pressure according to the master cylinder pressure or the secondary pump discharge pressure. In addition, L is a supply pressure port and M is a drain port. Here, the main valve 4 and the pilot valve 5 constitute an electronic hydraulic control valve e.

The TCS switching valve 6 has a three-position switching valve structure which is switched by a solenoid command from the outside, and guides the pump discharge pressure from the input port V to the output port W during the brake TCS control. In addition, C is a drain port.

The pressure reducing valve 7 is provided in the middle of the oil passage connecting the output port B of the TCS switching valve 6 and the secondary pump discharge pressure port N of the pilot valve 5, and the pump from the primary pressure port T is provided. The discharge pressure is adjusted to the secondary pump discharge pressure set by the spring, and the secondary pump discharge pressure is guided from the output port U to the secondary pump discharge pressure port N of the pilot valve 5.

The leak reducing switching valve 8 is provided in the middle of an oil passage connecting the oil pump 3 and the supply pressure ports I and L of the main valve 4 and the pilot valve 5 to operate the master cylinder pressure. The supply of the pump discharge pressure to the supply pressure ports I and L is cut off when the master cylinder pressure is not generated. In addition, F is a master cylinder pressure port, D is an input port, and E is an output port.

The pilot switching valve 9 is provided in the oil passage upstream of the wheel cylinder 2, and the fail valve 1 is provided.
The pump discharge pressure from 1 is used as the valve operating pressure, the control pressure port J of the main valve 4 is connected to the wheel cylinder 2 when the pump discharge pressure is generated, and the master cylinder 1 and the wheel cylinder 2 are connected when the pump discharge pressure is not generated. To connect. Incidentally, S
Is a pump discharge pressure port, R is a control pressure port, P is a master cylinder pressure port, and Q is a wheel cylinder pressure port.

The check valve 10 includes a downstream position of the leak reducing switching valve 8, the TCS switching valve 6 and the pressure reducing valve 7.
Is provided in the middle of the oil passage connecting the oil passage position between
Allow only the flow of hydraulic oil from the S switching valve 6 side. Incidentally, G
Is a TCS side port, and H is a control valve side port.

The fail valve 11 has a three-position switching valve structure which is switched by a solenoid command from the outside. When the system is normal, the pump discharge pressure is controlled by the pilot switching valve 9.
When the system fails, as shown in FIG. 2, it is switched to a position where the pump discharge pressure to the pilot switching valve 9 is shut off. In addition, X is a pump discharge pressure port, Y is an output port, and Z is a drain port.

The controller 12 controls selection of pump discharge pressure, drive control of the TCS switching valve 6, solenoid control of the main valve 4, and drive control of the fail valve 11. Here, the configuration of the pump discharge pressure selection control unit will be described.

First, as input sensors, a master cylinder pressure sensor 14, a wheel cylinder pressure sensor 15, a longitudinal acceleration sensor 16, a braking force sensor 17, and a brake temperature sensor 18 are provided (these sensors are respectively braking state detecting means). equivalent to f).

As output actuators, a low pressure range pressure switch 19, a high pressure range pressure switch 20, an output selection switch 21, a motor ON / OFF relay 22,
A coil excitation power supply 23 and a motor drive power supply 24 are provided (these correspond to pump discharge pressure control mode selection means h).

Next, the operation will be described.

[During non-braking] During non-braking when the system is normal and there is no TCS request, the TCS switching valve 6 is fixed at the position shown in FIG. 2, and the fail valve 11 is placed on the side for guiding the pump discharge pressure to the pilot switching valve 9. The pilot switching valve 9 is switched to the position where it is operated by the control pressure from the main valve 4. Further, since the master cylinder pressure from the master cylinder 1 is zero, the leak reduction switching valve 8 is fixed to the side that shuts off the ports D and E shown in FIG.

Therefore, since the pump discharge pressure from the oil pump 3 is completely shut off from the downstream supply by the leak reduction switching valve 8, the leakage of the main valve 4 and the pilot valve 5 from the spool is prevented. Therefore, the pump discharge flow rate of the oil pump 3 is prevented from being wasted.

[During Braking] During braking by braking, the master cylinder pressure generated by the master cylinder 1 switches the leak reducing switching valve 8 to the side for supplying the pump discharge pressure to the main valve 4 and the pilot valve 5.

Therefore, the pump discharge pressure from the oil pump 3 is supplied to the supply pressure ports I and L of the main valve 4 and the pilot valve 5 via the leak reduction switching valve 8, and the supply pressure at the pilot valve 5 becomes the master pressure. The pilot pressure is adjusted according to the magnitude of the cylinder pressure, and further, in the main valve 4, the supply pressure is adjusted to a control pressure according to the difference between the force generated by the pilot pressure and the force generated by the solenoid 4a. A braking force is applied to each wheel by supplying the pressure to the wheel cylinder 2.

When the brake is not operated but the brake TCS is carried out to suppress the occurrence of drive wheel slip, the TCS switching valve 6 is switched from the position shown in FIG. 2 to the position communicating the port V and the port W, The pump discharge pressure is divided into two parts, one is adjusted to the secondary pump discharge pressure via the pressure reducing valve 7, is guided to the secondary pump discharge pressure port N of the pilot valve 5, and the other is checked via the check valve 10. It is led to the supply pressure ports I and L of the valve 4 and the pilot valve 5.

As a result, the spool of the pilot valve 5 moves leftward in the drawing to generate a pilot pressure, and the main valve 4 also moves leftward in the drawing by the pilot pressure to connect the ports I and J to generate a control pressure. By supplying this control pressure to the wheel cylinder 2, the braking force is applied to the wheel that is causing the drive slip.

[Pump discharge pressure control mode selection action] First, as shown in FIG. 3, the operation characteristic of the low pressure range pressure switch 19 is that when the pump discharge pressure rises and reaches Pmax1 in the switch OFF state, the switch is turned ON. Becomes Also, when the pump discharge pressure decreases and reaches Pmin1 while the switch is ON, the switch is turned OFF, OFF → ON and ON → O.
Hysteresis is provided in the pressure level of the FF.

The operating characteristics of the high pressure range pressure switch 20 are as follows.
As shown in FIG. 4, when the pump discharge pressure rises and reaches Pmax2 while the switch is OFF, the switch is ON. Also, when the switch is ON, the pump discharge pressure decreases and P
When min2 is reached, the switch is turned off, and hysteresis is provided for the pressure levels of OFF → ON and ON → OFF.

Pressure switches 19 and 2 having the above operating characteristics
0 to the pump discharge oil passage as shown in FIG.
One end of the contacts of the pressure switches 19 and 20 is connected to the two contacts of the output selection switch 21, respectively, and the other end is connected to the motor O.
Connect to the coil of N / OFF relay 22. A coil excitation power supply 23 is connected between the coil and the output selection switch 21, and a motor drive power supply 24 is connected in series to the contacts A and B of the motor ON / OFF relay 22 and the electric motor 13. Connecting.

Therefore, when the low pressure range pressure switch 19 is selected by the selection command to the output selection switch 21, the pump discharge pressure is in the low pressure range control mode, and when the high pressure range pressure switch 20 is selected, the pump is discharged. The low pressure range control mode and the high pressure range control mode can be obtained by the selection command from the controller 12 to the output selection switch 21 such that the discharge pressure becomes the high pressure range control mode.

[Pump Discharge Pressure Control Operation] FIG. 5 is an example of a flowchart showing the flow of the pump discharge pressure control operation performed by the controller 12, and each step will be described below (corresponding to the pump discharge pressure control means g).

At step 51, the master cylinder pressure sensor 14 detects the master cylinder pressure Pm1.

In step 52, the master cylinder pressure Pm1
Is determined to be equal to or higher than the set pressure Pm0.

In step 53, when Pm1 ≧ Pm0,
The command output for selecting the high pressure range pressure switch 20 is held for Δt seconds.

In step 54, when Pm1 <Pm0,
A command for selecting the low pressure range pressure switch 19 is output.

Therefore, Pm1 <Pm0 during normal braking, etc.
If so, the flow proceeds from step 51 to step 52 and then to step 54. In step 54, the low pressure range pressure switch 19 is selected, and the pump discharge pressure is controlled in the low pressure range control mode. In addition, when braking suddenly, Pm1 ≧
When it is Pm0, the flow proceeds from step 51 → step 52 → step 53. In step 53, the high pressure range pressure switch 20 is selected, and the pump discharge pressure is controlled by the high pressure range control mode.

Here, the high pressure region control mode is maintained for Δt seconds. Once it is determined that a high wheel cylinder pressure is required, the state may continuously occur for a while. This is because it is necessary to continue rotating the pump 3 in the high pressure range.

Although the flowchart of FIG. 5 shows an example in which the high pressure range control mode is selected when the master cylinder pressure Pm1 is equal to or higher than the threshold value Pm0, the master cylinder pressure from the wheel cylinder pressure sensor 15 and the longitudinal acceleration sensor are selected. The deceleration (deceleration G) from 16, the braking force from the braking force sensor 17, the rotor temperature and the pad temperature from the brake temperature sensor 18 are also in the high pressure region control mode when the threshold values are exceeded. Is selected.

[Detection of Braking Force] As described above, various modes have been shown as modes of detecting the braking state. Among them, a suitable example of braking force detection will be described below.

Specific Example of Braking Force Detection A load sensor is attached to the caliper mounting portion to detect the force applied to the caliper during braking.

A load sensor is attached to the body side mounting portion of the suspension link or the wheel side mounting portion of the link to detect the force applied to the link during braking.

Necessity of Control Based on Braking Force Since the present invention increases the pump discharge pressure when a large braking force is required, it is most direct and reliable to detect and judge the braking force. is there. Further, the braking force detection has the following advantages.

For example, in the case of the ABS control, since the wheel speed control is currently performed, it is necessary to detect the wheel speed and estimate or detect the vehicle speed. With this proportional control brake, it is difficult to estimate the vehicle body speed, and therefore a vehicle body speed detecting means is required, which is costly. Further, the vehicle speed detection itself is quite difficult because there are practically only methods using the components of the front and rear G sensors.

The reason why the wheel speed is controlled by ABS is that the braking force generally becomes maximum when the wheel slip ratio is 15%. However, on the gravel road, the braking force becomes higher when the wheels tend to be locked. Therefore, according to the current ABS control, the braking distance is greatly extended on the gravel road. On the other hand, in the ABS control by detecting the braking force, since the braking force can be directly controlled, the braking force can be maximized regardless of the road surface, and the braking distance can be shortened on any road surface including the gravel road. it can.

[Pump Discharge Pressure Control Operation in Low Pressure Range Control Mode] FIG. 6 is a flowchart showing the flow of pump discharge pressure control operation in the low pressure range control mode in which the low pressure range pressure switch 19 is selected.

First, when the output selection switch 21 selects the low pressure range pressure switch 19 (step 60) and when the pump discharge pressure is less than Pmax1 (step 61), the low pressure range pressure switch 19 is off (step 60). 62), the coil of the relay 22 is de-energized (step 6).
3) The contacts A and B of the motor ON / OFF relay 22 are turned on (step 64), the electric motor 13 is rotated by the motor driving power source 24 (step 65), and pump discharge operation is performed (step 66). .

When the pump discharge pressure rises above Pmax1 due to the increase in the pump discharge pressure (step 6)
1) When the low pressure range pressure switch 19 is turned on (step 67) and the coil of the relay 22 is energized (step 68), conduction between the contacts A and B of the motor ON / OFF relay 22 is cut off ( In step 69), the electric motor 13 is stopped and rotated (step 70), and the pump discharge is also stopped (step 71). This pump stop is continued as long as the pump discharge pressure exceeds Pmin1 (step 7).
2). Furthermore, when the pump discharge pressure decreases and the pump discharge pressure becomes Pmin1 or less, step 72 to step 62-
The routine proceeds to step 66, where the pump discharge operation is performed again.

Therefore, in this low pressure range control mode,
As shown in FIG. 3, the pump discharge pressure is approximately Pmin1 to Pmax1.
It will be controlled so that the pressure becomes.

[Pump Discharge Pressure Control Operation in High Pressure Range Control Mode] FIG. 7 is a flowchart showing the flow of pump discharge pressure control operation in the high pressure range control mode in which the high pressure range pressure switch 20 is selected.

First, when the output selection switch 21 selects the high pressure range pressure switch 20 (step 80) and when the pump discharge pressure is less than Pmax2 (step 81), the high pressure range pressure switch 20 is off (step 80). 82), the coil of the relay 22 is de-energized (step 8).
3) The contacts A and B of the motor ON / OFF relay 22 are turned on (step 84), the electric motor 13 is rotated by the motor driving power source 24 (step 85), and the pump discharge operation is performed (step 86). .

When the pump discharge pressure exceeds Pmax2 due to the increase in the pump discharge pressure (step 8)
1) When the pressure switch 20 for the high pressure region is turned on (step 87) and the coil of the relay 22 is energized (step 88), the conduction of the contacts A and B of the motor ON / OFF relay 22 is cut off ( In step 89), the electric motor 13 is stopped and rotated (step 90), and the pump discharge is also stopped (step 91). This pump stop is continued as long as the pump discharge pressure exceeds Pmin2 (step 9).
2). Furthermore, when the pump discharge pressure decreases and the pump discharge pressure becomes Pmin2 or less, step 92 to step 82-
In step 86, the pump discharge operation is performed again.

Therefore, in this high pressure range control mode,
As shown in FIG. 4, the pump discharge pressure is approximately Pmin2 to Pmax2.
It will be controlled so that the pressure becomes.

Next, the effect will be described.

(1) In the brake control device having the oil pump 3 driven by a motor, the pump discharge pressure control from the oil pump 3 is made low only when a braking state requiring a pump discharge pressure in a low pressure range or higher is detected. Since the pump discharge pressure control is performed by switching from the region control mode to the high pressure region control mode, it is possible to reduce current consumption while ensuring compatibility with a high pump discharge pressure request.

That is, the pump discharge pressure and the current consumption are
As shown in FIG. 8, it is in a proportional relationship, but the pump operating time in the high pressure region where the current consumption greatly increases can be suppressed to the minimum necessary only when the high pump discharge pressure is required.

(2) When controlling the pump discharge pressure, the master cylinder pressure or the wheel cylinder pressure is detected, and when the pressure detection value exceeds a certain threshold value, the deceleration is detected. When a certain threshold is exceeded, the braking force is detected, and when this braking force detection value exceeds a certain threshold, the rotor temperature and the brake caliper pad temperature are detected, and this temperature detection value reaches the fade condition range. When it is determined that the master cylinder pressure or the wheel cylinder pressure is high, the control device switches the low pressure region control mode to the high pressure region control mode when any one of the above conditions is satisfied. When the braking deceleration is a high deceleration, a high braking force, or a fade state, it is possible to reduce the current consumption while meeting the high pump discharge pressure request.

(3) The low pressure range pressure switch 19 and the high pressure range pressure switch 2 in which the pump discharge pressure from the oil pump 3 can be selected between the low pressure range control mode and the high pressure range control mode.
0, an output selection switch 21, and a motor ON / OFF relay 22 are provided, and the output selection switch 21 is provided only when a braking state requiring a pump discharge pressure in a low pressure range or higher is detected.
Since the device for outputting a selection command to switch from the low pressure region control mode to the high pressure region control mode is
As compared with the case of performing the rotation speed control of 3 and the ON / OFF direct drive control, the low pressure region control mode and the high pressure region control mode can be obtained by the pump discharge pressure control by a simple selection command.

Although the embodiments have been described above with reference to the drawings, the specific configuration is not limited to the embodiments, and modifications and additions within the scope of the present invention are included in the present invention. Be done.

In the embodiment, as the hydraulic control valve, the type in which the main valve and the pilot valve are divided into two is shown, but one electronic hydraulic pressure as described in Japanese Patent Laid-Open No. 4-87867 is used. It may have a control valve structure.

In the embodiment, the example of the oil pump driven by the electric motor is shown, but the invention can be applied to the oil pump driven by the engine. In this case, it is possible to improve fuel efficiency instead of reducing current consumption.

[0082]

According to the first invention of claim 1,
In a brake control device having an oil pump driven by an actuator as an oil pump, the pump discharge pressure control from the oil pump is made low only when a braking condition requiring a pump discharge pressure in a low pressure range or higher is detected by the braking condition detecting means. Since the device is provided with a pump discharge pressure control means for switching from the region control mode to the high pressure region control mode, it is possible to reduce consumption current and improve fuel consumption while ensuring compatibility with high pump discharge pressure requirements. The effect is obtained.

According to a second aspect of the present invention, in the brake control device according to the first aspect, the pump discharge pressure control means is provided to detect the master cylinder pressure or the wheel cylinder pressure, and detect the pressure. When a deceleration is detected and this deceleration detection value exceeds a certain threshold value. Braking force is detected and this braking force detection value exceeds a certain threshold value. When the rotor temperature or the pad temperature of the brake caliper is detected and it is determined that the detected temperature value has reached the fade condition range When any one of the above conditions is satisfied, the low pressure range control mode to the high pressure range Since it is a means to switch to the control mode, when the master cylinder pressure or wheel cylinder pressure is high, the braking deceleration is high deceleration, the braking force is high, or the fade condition is met, the high pump discharge pressure requirement is met. Reluctant, there is an advantage that it is possible to improve the reduction and fuel efficiency of current consumption.

According to a third aspect of the present invention, in the brake control device according to the first aspect or the second aspect, the pump discharge pressure from the oil pump is controlled in a low pressure range control mode and a high pressure range control mode. A pump discharge pressure control mode selection means that can be selected is provided, and the pump discharge pressure control means is set to a low pressure range with respect to the pump discharge pressure control mode selection means only when a braking state requiring a pump discharge pressure higher than the low pressure range is detected. Since the means for outputting the selection command for switching from the control mode to the high pressure region control mode is used, in addition to the above effects, the low pressure region control mode and the high pressure region control mode can be obtained by pump discharge pressure control by a simple selection command. The effect is obtained.

[Brief description of drawings]

FIG. 1 is a claim correspondence diagram showing a brake control device of the present invention.

FIG. 2 is an overall system diagram showing a brake control device according to an embodiment.

FIG. 3 is an operation explanatory diagram of a low pressure range pressure switch.

FIG. 4 is an operation explanatory view of a high pressure range pressure switch.

FIG. 5 is a flowchart showing a flow of a pump discharge pressure control operation performed by the controller of the embodiment apparatus.

FIG. 6 is a flowchart showing a flow of pump operation in a low pressure region control mode in which a low pressure region pressure switch is selected.

FIG. 7 is a flowchart showing a flow of pump operation in a high pressure region control mode in which a high pressure region pressure switch is selected.

FIG. 8 is a characteristic diagram of consumed current with respect to pump discharge pressure in a low pressure region and a high pressure region.

[Explanation of symbols]

 a master cylinder b wheel cylinder c drive actuator d oil pump e electronic hydraulic control valve f braking state detection means g pump discharge pressure control means h pump discharge pressure control mode selection means

Claims (3)

[Claims] 1. A master cylinder that generates a master cylinder pressure according to a brake operation force, a wheel cylinder that is provided in a braking device for each wheel and that is operated by control pressure, and a liquid that is driven by a drive actuator regardless of brake operation. The oil pump that generates pressure and the master cylinder pressure as the signal pressure, the force generated by the signal pressure and the force generated by the solenoid are input, and the external hydraulic pressure supplied from the external hydraulic pressure source is determined according to the difference between the two inputs. An electronic hydraulic control valve for adjusting the control pressure, a braking state detecting means for detecting a braking state, a pump discharge pressure in a low pressure range, and a pump discharge pressure in a high pressure range,
An oil pump as an external hydraulic pressure source capable of discharging, and the pump discharge pressure control means inputs the detection signal from the braking state detecting means, and controls the pump discharge pressure of the oil pump to a low pressure range control mode and a high pressure range control. A brake control device comprising: pump discharge pressure control means for switching between modes. 2. The brake control device according to claim 1, wherein the braking state detecting means detects a master cylinder pressure or a wheel cylinder pressure, and a deceleration detecting means detects a deceleration in a front-rear direction of the vehicle. At least one of a braking force detecting means for detecting a braking force or a temperature detecting means for detecting a temperature of a rotor or a brake caliper, the pump discharge pressure control means: When the value exceeds a certain threshold value ・ When the deceleration detection value of the deceleration detection means exceeds a certain threshold value ・ When the braking force detection value of the braking force detection means exceeds a certain threshold value ・ Temperature When it is determined that the temperature detection value of the detection means has reached the fade state range When the one of the above conditions is satisfied, the low pressure range control mode is switched to the high pressure range control mode. Brake control apparatus according to claim and. 3. The brake control device according to claim 1, further comprising pump discharge pressure control mode selection means for selecting a pump discharge pressure from the oil pump in a low pressure range control mode and a high pressure range control mode. The pump discharge pressure control means is switched from the low pressure range control mode to the high pressure range control mode for the pump discharge pressure control mode selection means only when a braking state requiring a pump discharge pressure above the low pressure range is detected. A brake control device characterized by being a means for outputting a selection command.