JP2000095094A - Brake fluid pressure control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake fluid pressure control device capable of controlling the fluid pressure of a brake cylinder without depending on the control of electric energy supplied to a pressure intensifying solenoid fluid pressure control valve and the control of electric energy supplied to a pressure reducing solenoid fluid pressure control valve. SOLUTION: A pumping device exclusively used to intensify pressure is connected to wheel cylinders 18, 24, 50, 52, while a master reservoir 31 is connected to these wheel cylinders through pressure reducing solenoid fluid pressure control valves 58, 62. Wheel cylinder fluid pressure at the time of intensifying pressure can be controlled by controlling the pressure of an operating fluid discharged from the pumping device 30, and fluid pressure at the time of reducing pressure can be controlled by controlling the pressure reducing solenoid fluid pressure control valves 58, 62. In this brake fluid control device, wheel cylinder fluid pressure is thus controlled by the control of the pumping device 30 and the control of the pressure reducing solenoid fluid pressure control valves 58, 62.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake hydraulic pressure control device for controlling a hydraulic pressure of a brake cylinder.

[0002]

2. Description of the Related Art The specification of Japanese Patent Application No. 9-121039 filed by the present applicant and not yet disclosed discloses a brake fluid pressure control device using a power fluid pressure source as a high pressure source. This brake fluid pressure control device includes a pump and an electric motor that drives the pump, and an accumulator that stores high-pressure hydraulic fluid discharged from the pump,
A high-pressure source that supplies high-pressure hydraulic fluid to the brake cylinder;
A low-pressure source that contains the hydraulic fluid that has flowed out of the brake cylinder; and a low-pressure source that is provided between the high-pressure source and the brake cylinder. Electromagnetic pressure control valve provided between the low-pressure source and the brake cylinder for controlling the hydraulic pressure of the brake cylinder to a magnitude corresponding to the supplied electric energy. Controlling the valve and the electric motor so that the hydraulic pressure of the hydraulic fluid stored in the accumulator is maintained at a predetermined set hydraulic pressure, and the electromagnetic pressure control valve for pressure increase and the electromagnetic fluid for pressure reduction are maintained. A control device for controlling the brake cylinder hydraulic pressure by controlling the pressure control valve. When pressure increasing control is performed in the brake fluid pressure control device, the electric energy supplied to the pressure increasing electromagnetic fluid pressure control valve is controlled while the pressure reducing electromagnetic fluid pressure control valve is closed. By controlling the electric energy supplied to the pressure-increasing electromagnetic hydraulic pressure control valve, the hydraulic pressure of the working fluid in the accumulator is appropriately reduced and supplied to the brake cylinder. When the pressure reduction control is performed, the electric energy supplied to the pressure reduction electromagnetic hydraulic pressure control valve is controlled while the pressure increase electromagnetic hydraulic pressure control valve is closed. The hydraulic pressure of the brake cylinder is reduced to a magnitude corresponding to the electric energy supplied to the pressure reducing electromagnetic hydraulic pressure control valve. The hydraulic pressure of the brake cylinder is controlled by controlling the electric energy supplied to the pressure increasing electromagnetic hydraulic pressure control valve and controlling the electric energy supplied to the pressure decreasing electromagnetic hydraulic pressure control valve.

[0003]

Problems to be Solved by the Invention, Means of Solution, Functions and
An object of the present invention is to provide a brake fluid pressure control device.
To provide another new brake fluid pressure control device.
You. Specifically, the electric power supply to the pressure increasing electromagnetic hydraulic pressure control valve
Control of energy and supply of electric energy to the electromagnetic pressure control valve for pressure reduction
Without depending on the control of the lugi, raise the hydraulic pressure of the brake cylinder
To provide a controllable brake fluid pressure control device.
You. This problem is solved by the following aspects. Each state
, Like the claims, classify them into sections, number each section,
Enter the number of another section as necessary.
This includes the technical features described herein and their sets.
For the purpose of illustrating the alignment, the technical
Features and their combinations are limited to:
Should not be interpreted as (1) Connected to the brake cylinder,
Pump that discharges hydraulic fluid toward the pump and drives the pump
A pump device including at least one set of an electric motor that performs
Contains the hydraulic fluid flowing out of the brake cylinder
Between the low pressure source and the brake cylinder.
The brake cylinder hydraulic pressure is provided between
An electromagnetic hydraulic pressure control valve for controlling the size according to the energy,
The brake system is controlled by controlling the electric motor.
Pressure increasing control means for increasing the pressure of the liquid in the cylinder;
Brake cylinder by controlling electric energy
A control device including pressure reduction control means for reducing the pressure of the liquid pressure;
A brake fluid pressure control device comprising:
1). The simplest of the brake fluid pressure control devices described in this section
The aspect is that an electromagnetic valve is provided between the pump device and the brake cylinder.
The brake cylinder does not have
Pump will be directly connected. In addition,
A low-pressure source is connected to the key cylinder via the electromagnetic hydraulic pressure control valve
Is done. In this brake fluid pressure control device,
Check that the hydraulic fluid discharged from the
The hydraulic pressure of the brake cylinder is increased by
Control of the electric motor that drives the pump
The hydraulic pressure of the damper can be controlled to increase. Also brake
The hydraulic fluid in the cylinder is drained to a low pressure source.
The hydraulic pressure of the brake cylinder is reduced,
Hydraulic pressure depends on the electrical energy supplied to the electromagnetic hydraulic control valve.
The pressure can be controlled to a small size. Thus, the book
In the brake fluid pressure control device described in the paragraph, the pump is
Control of the electric motor to be driven and supply to the electromagnetic hydraulic pressure control valve
Of the brake cylinder
The hydraulic pressure is controlled. That is, the aforementioned brake fluid pressure control
As in the device, the electromagnetic hydraulic control valve for pressure boost and pressure reduction
Supply electric energy to each electromagnetic hydraulic pressure control valve
It is not controlled by control.
The electromagnetic hydraulic pressure control valve has a size corresponding to the supplied electric energy.
In addition, the hydraulic pressure of the brake cylinder can be controlled.
However, as the supplied electric energy increases, the brake cylinder
Supply energy, even if the hydraulic pressure of the
When the hydraulic pressure of the brake cylinder decreases
May be used. In addition, the invention according to this section
One brake cylinder is connected to the pump device
Or multiple brakes on one pump unit
Cylinders are connected and their hydraulic pressures are commonly controlled
It is desirable to apply in cases. Therefore, the control
The arrangement can be referred to as a common hydraulic control. Note that
Multiple brake cylinders are connected to the pump device,
It is necessary to control the hydraulic pressure of each brake cylinder independently.
Pump system and brake system as described below.
A throttle device can be provided between each cylinder and the brake cylinder.
The pump to or from the pump device.
It is desirable to provide a pump shut-off valve. (2) The pressure reduction control means controls the electric pressure during the pressure reduction control.
Stop the motor.
Place. If the electric motor is stopped, the brake cylinder
Fluid is not supplied. Therefore, the electric motor is driven
The brake cylinder fluid
The pressure can be reduced quickly. In addition, the control device
The electric motor is stopped and the electromagnetic hydraulic pressure is
Actuating a control valve from the brake cylinder to the low pressure source
Holding control means to prevent the liquid from flowing out
It can also be provided. When the electric motor is stopped
If the electro-hydraulic pressure control valve is kept in the outflow prevention state,
Both the outflow and inflow of hydraulic fluid in the
As a result, the hydraulic pressure can be stably kept constant. (3) The control device is configured to control a target fluid of the brake cylinder.
The hydraulic pressure deviation, which is the difference between the pressure and the actual hydraulic pressure,
The difference between the current target hydraulic pressure and the previous target hydraulic pressure
Based on at least one of the required hydraulic pressure change gradient
Between the pressure increasing control means and the pressure reducing control means.
The brake fluid pressure control device according to the above mode (1) or (2).
As an example of selection based on hydraulic pressure deviation,
For example, the target hydraulic pressure Pref and the actual hydraulic pressure P ^* Hydraulic deviation which is the difference from
(ΔP = Ppef−P ^* ) Is the set deviation EPS (threshold
Value) (ΔP> EPS), the pressure increase control means
Is selected and the hydraulic pressure deviation ΔP is less than or equal to the set deviation (EPS).
(ΔP ≦ EPS), the pressure reduction control means is selected.
Can be done. In addition, when holding control means is included
The hydraulic pressure deviation ΔP is larger than the positive set deviation EPS1
In this case (ΔP> EPS1), the pressure increase control means is selected, and
When the pressure deviation ΔP is smaller than the negative set deviation (−EPS2)
(ΔP <−EPS2), the pressure reduction control means is selected,
When the pressure deviation ΔP is within the set deviation range (−EPS2 ≦ Δ
(P ≦ EPS1) so that the holding control means is selected.
be able to. Furthermore, not only the hydraulic pressure deviation, but also the required hydraulic pressure
As an example of selection in consideration of the change gradient,
The difference ΔP is larger than the positive set deviation EPS1, but the required hydraulic pressure
If the change gradient ΔPref is equal to or less than the positive set gradient RPS1,
(ΔP> EPS1, ΔPref ≦ RPS1)
The holding control means is selected instead of the control means, and the hydraulic pressure deviation ΔP
Is smaller than the negative setting deviation (-EPS2),
When the change gradient ΔPref is equal to or greater than the negative set gradient (-RPS2)
In some cases (ΔP <−EPS2, ΔPref ≧ −RPS2)
Is to select hold control instead of pressure reduction control
be able to. Note that the positive setting deviation EPS1 and the negative
Set deviation-EPS2, positive set slope RPS1 and negative set
The absolute value of the gradient -RPS2 can be the same. (4) The control device controls the electric motor to
The required pressure increase gradient of the key cylinder is the preset pressure increase gradient.
The output torque is larger when the torque is larger than when the torque is smaller.
(1) Including the motor control device that controls
The brake fluid pressure control device according to any one of the items (3) to (3).
(Claim 2). Increase output torque of electric motor
Increase the discharge flow rate of the hydraulic fluid discharged from the pump.
Or increasing the discharge pressure (hereinafter simply referred to as discharge
(Abbreviated as increasing the flow rate or the like). The result
As a result, increasing the pressure increase gradient of the brake cylinder
To reduce or eliminate the pressure increase delay
it can. At the start of brake fluid pressure control for normal braking (break
At the start of the braking operation of the key operation member), emergency braking
During cyst control, etc., the required pressure increase gradient is
It is often large and effective. Above set pressure increase gradient
For example, by controlling a normal electric motor,
Brake when the output torque of the
Cylinder fluid pressure increase gradient (Upper limit gradient during normal control)
The electric motor is provided with the brake fluid pressure control device.
Pressure gradient when the maximum voltage of a charged battery is applied
(Gradient at the time of battery voltage application)
You. When the required pressure increase gradient is larger than this set pressure increase gradient
Means that the voltage applied to the electric motor is
Or higher than the maximum voltage of the power supply (battery)
To When the supply current is made larger than during normal control
is there. In these cases, the output torque of the electric motor is large.
May not be able to control the size,
It is sufficient if the hydraulic pressure of the brake cylinder can be increased
What is possible is not essential. This motor control device
Is referred to as the motor control device during sudden pressure increase,
Special increase device, pump discharge flow rate increase device, etc.
Can be In this way, the required pressure increase gradient
If the output torque of the electric motor is
If the discharge flow rate of the pump device is increased,
Increase the brake cylinder without increasing the motor capacity.
Pressure gradient can be increased to avoid cost increase
Can be Normal control of the electric motor
To increase the discharge flow rate of the pump device,
By increasing the upper limit of
Increasing the brake cylinder fluid pressure with a gradient
In order to achieve this, the capacity of the electric motor must be increased.
And cost increases cannot be avoided. So
In contrast, the controllable range remains
The applied voltage to the electric motor in special cases
To increase the capacity of the electric motor.
Pressure can be increased with a gradient higher than the set pressure increase gradient.
Become. The features described in this section are based on any of (1) to (3).
Any of the features described in any one of them can be adopted. sand
In other words, a pump device dedicated to increasing the brake cylinder hydraulic pressure
Control and the control of the electromagnetic pressure control valve for pressure reduction.
The above-described control is not limited to
For pressure increase and pressure reduction, even if control is added
Even if controlled by controlling the solenoid on-off valve,
Controlled by the control of a pressure pump and a pressure reducing pump.
It may be. (5) The motor control device applies the voltage to the electric motor.
An applied voltage increase device that makes the voltage larger than the voltage of the power supply
The brake fluid pressure control device according to item (4). Electric motor
Applied voltage is higher than the maximum voltage of a power source such as a battery.
Then, the output torque of the electric motor can be increased.
The discharge flow of the pump device can be increased.
You. Applied voltage increase devices include, for example, coils, capacitors
And drive circuits including switches such as transistors
Or include a DC-DC converter
Or include a boost converter
You. (6) Whether the controller is not operating the electric motor
When switching to the operating state from the
Includes motor controller at start of operation to increase applied voltage
Brake fluid according to any one of paragraphs (1) to (3)
Pressure control device. At the start of operation, the voltage applied to the electric motor
The electric motor is quickly driven to the desired operating state
(Rotational speed and drive torque) can be
It is possible to quickly set the discharge flow rate of the
it can. Normal voltage when motor is inactive
To the desired operating state immediately due to inertia
Can not do. In contrast, the brakes described in this section
According to the hydraulic pressure control device, a large voltage is applied at the start of operation
As a result, the discharge flow rate of the pump
The delay in pressure increase of the brake cylinder
Can be smaller. The applied voltage is
Increase the time by a predetermined set time or
Until the cylinder fluid pressure reaches a predetermined set fluid pressure
And can be made larger. The features described in this section are
Different from the features described in any one of paragraphs (1) to (3)
It can also be implemented. (7) The control device controls the hydraulic pressure of the brake cylinder.
If the required hydraulic pressure change gradient is within a predetermined set range,
In this case, stop the electric motor and
The pressure control valve controls the outflow of hydraulic fluid from the brake cylinder.
Including holding control means for switching to outflow prevention state
Brake fluid according to any one of paragraphs (1) to (6)
Pressure control device (Claim 3). Brake fluid pressure control described in this section
In the control device, the required hydraulic pressure change of the brake cylinder
If the gradient is within the set range,
The hydraulic pressure is not changed according to the required hydraulic pressure change.
And kept at a certain size. For example, if the setting range is
Unintentional brake operation amount of the driver (operation of the brake operation member)
(Acting force, operation stroke, etc.)
The driver intends to change the amount of braking.
Useless energy is consumed by the operation of the pump unit
Thus, the generation of operation noise is avoided. Also especially
The driver may change the amount of brake operation while the vehicle is running.
The deceleration changes even though there is no
Can be prevented from becoming worse. In addition, the driver
It is no longer necessary to carefully maintain a constant
This also has the effect of simplifying the key operation. Features described in this section
Is the feature described in any one of paragraphs (1) to (6).
Can be adopted separately. (8) The control device is configured to control the holding by the holding control unit.
When the control time is long, the setting range is wider than when the control time is short.
Brake fluid according to item (7)
Pressure control device (Claim 4). If the above holding control time is long
The driver wants to keep the braking force constant.
In this case, the setting range should be widened,
It is desirable to make it difficult for brake fluid pressure to change
It is. Also, there is a chance that the electric motor is deactivated.
Energy consumption in the pump device
Can be eliminated. The setting range is based on the retention control time.
Regardless of whether the size is increased step by step or continuously
Good. (9) The control device satisfies a predetermined holding condition.
The electric motor is stopped and
The hydraulic fluid control valve is connected to the hydraulic fluid from the brake cylinder.
Control hand to switch to outflow prevention state to prevent outflow of water
Stage and the holding control time by the holding control means is long
Is more relaxed than the shorter case.
Any one of paragraphs (1) to (6), including means
Brake fluid pressure control device. For example, the hydraulic pressure deviation ΔP is set
Within the range (EPS1 ≧ ΔP ≧ −EPS2).
In the case of the holding condition, the upper limit value EPS1 of the setting range is increased.
And lowering the lower limit -EPS2.
The holding condition is relaxed by performing at least one.
It is. If the holding condition is with or
The same applies when set by the required hydraulic pressure change gradient instead of
It is. The features described in this section are defined in paragraphs (1) to (6).
Any one of the features described above may be adopted separately. (10) The control device satisfies a predetermined holding condition.
When the operation of the electric motor is stopped
Both switches the electromagnetic hydraulic control valve to the outflow prevention state
Holding control means and the brake fluid pressure control device
When the vehicle is stopped, loosen the holding condition.
Items (1) to (9)
The brake fluid pressure control device according to any one of the preceding claims. Vehicle stopped
If it is in the state, the brake
The need to increase or decrease the rake cylinder fluid pressure
Should be kept low and constant. Hold when stopped
If the conditions are relaxed, the driver must carefully consider the amount of brake operation.
It is no longer necessary to maintain a constant
This increases the chances of reducing energy consumption.
Regarding the change of the retention condition, the explanation in the above (9)
apply. The features described in this section are defined in paragraphs (1) to (9).
In addition to the features described in any one of the above, the present invention can be adopted. (11) The control device determines that a predetermined pressure increase condition is satisfied.
By controlling the electric motor when
Pressure increasing means for increasing the brake cylinder fluid pressure;
Wheel speed of the vehicle equipped with the
Once the pressure has become substantially zero, the pressure increase condition is satisfied
Also, the electric motor is stopped and the electromagnetic hydraulic pressure
Control valve to prevent hydraulic fluid from flowing out of brake cylinder
Forced holding execution means to keep in the outflow prevention state and the forced holding
During the function of the execution means, the wheel speed exceeds the set wheel speed.
When the brake operation amount is increased,
No forced hold execution means to release the function of forced hold execution means
Any one of paragraphs (1) to (10), including
A brake fluid pressure control device as described in the above. When the vehicle is stationary
If the brake operation amount is increased,
Therefore, there is little need to increase the brake cylinder fluid pressure.
It should just be kept constant. Therefore, the brake fluid pressure of this embodiment
The control device is provided with forced holding execution means. But,
For example, if you stop at an intersection due to a stop signal, etc.
The vehicle was moved due to a rear-end collision of a following vehicle
When the vehicle is stopped on a slope or when the brake
Starts to move even though is not released
The braking force increases as the amount of brake operation increases.
Need to be done. Therefore, the brake fluid of the present embodiment
The pressure control device is provided with a forced holding execution means invalidating means.
You. The features described in this section are based on any one of paragraphs (1) to (10).
One of the features described above can be adopted separately. (12) The control device satisfies a predetermined pressure increasing condition.
Increase the brake cylinder fluid pressure if
Pressure increasing command means for issuing a pressure increasing command;
Starting the electric motor based on the signs
Any of paragraphs (1) to (11), including the front motor starting means
The brake fluid pressure control device according to any one of claims 1 to 5. Increase
Before the pressure command is generated, but before the pressure increase condition is satisfied
Starting the electric motor based on the indication will reduce the pressure increase delay.
Can be frustrated. Pre-motor starter described in this section
The stage is a precursor detection method that detects precursors that satisfy the pressure increase condition.
It can include steps. The boost condition is met
Detection predicts that pressure boosting conditions will be met in the near future
This is performed by detecting the occurrence of a possible situation. For example, blur
The pressure increase condition is satisfied when the operating member is operated
The operation of the accelerator operation member is released
If the traction control start condition is satisfied,
When conditions are met, start traction control
The traction control start prediction condition that is looser than the condition is satisfied.
In such a case, a precursor is detected. Described in this section
The feature of is described in any one of the paragraphs (1) to (11).
It can be adopted separately from the features. (13) The electric motor is started by the preliminary electric motor starting means.
After the start of
If the condition is not satisfied, stop the operation of the electric motor.
The brake according to item (12) including an electric motor stopping means for stopping the motor.
Pressure control device. A precursor to meet pressure boost conditions is detected
The pressure increase condition is satisfied by the set time.
If not, starting the electric motor may be useless.
Therefore, it is desirable to stop the operation of the electric motor.
No. The electric motor stops when the precursor phenomenon disappears.
It can be stopped. For example, track
The electric motor is switched off when the
If started, then the traction control start prediction condition
If the situation is no longer met, stop it. (14) the brake fluid pressure control device
The actual acceleration of a vehicle equipped with a pressure control device
Acceleration estimated based on the driving torque of the driving source
If the vehicle is traveling downhill,
The pre-motor starting means,
However, the downhill traveling state is detected by the downhill traveling detection device.
Detecting the detection as at least one of the precursors,
Means for starting the electric motor during downhill running
The brake fluid pressure control device according to the paragraph (12) or (13)
(Claim 6). When driving downhill, brake operation
Because the working members are often operated,
If the warning is detected, the
Once started, reduce the brake pressure increase delay.
Can be. The downhill traveling detection device detects the actual acceleration.
It is supposed to include an acquisition device and an estimated acceleration acquisition device.
Wear. The actual acceleration acquisition device includes an acceleration sensor
Or a wheel speed sensor and a wheel speed sensor
Calculate the acceleration based on the output wheel speed
And acceleration calculation means.
You. The estimated vehicle speed is obtained based on the wheel speed, and the estimated vehicle speed is obtained.
The speed of change of the speed per unit time is regarded as the actual acceleration.
It is. The estimated acceleration acquisition device is, for example, a driving source of a vehicle.
Device that estimates acceleration based on the drive torque of
Can be. [Description of Embodiments]
From the driving torque F output from the driving source of the vehicle
Value obtained by subtracting road load torque F 'by vehicle weight M
{(FF ′) / M} is set as the estimated acceleration. Drive source
At least an internal combustion engine such as an engine and an electric motor
Although the driving torque includes one of these,
Obtained as the sum of the torque. The vehicle runs on a flat surface
The actual acceleration and the estimated acceleration are substantially
Will be the same. On the other hand, when traveling uphill,
The actual acceleration is smaller, and when traveling downhill,
The actual acceleration is larger. If you use this, you can go downhill
It can be detected whether or not the vehicle is running. (15) The motor starting means while traveling on a downhill is the
In addition to detecting the slope running condition, the operation of the accelerator
The cancellation of the electric motor
Motor starts when accelerator is released during downhill running
Means for determining that the slope of the downhill is greater than a set slope.
Is detected as one of the precursors.
Motor starting means during steep downhill driving to start the motor
Motor starting means during downhill traveling provided with at least one of the following:
(14) The brake fluid pressure control device according to the above mode (14). Downhill running
According to the motor start means when the accelerator is released during running, the vehicle is running downhill.
When the operation of the accelerator operation member is released during
The dynamic motor can be started. A
When the operation of the xel operation member is released, the engine
The intention to reduce the running speed of the vehicle by using the brake
Since the driver can presume that the driver
The probability that the member is operated is increased. Also, steep downhill
According to the motor starting means during traveling, the slope of the downhill is the set slope.
If it is detected that the gradient is greater than the slope,
It can be activated. Large gradient
If the brake operation member is operated than if it is smaller
Probability is high. The slope of the slope is, for example,
The greater the difference from the estimated acceleration, the steeper the slope
be able to. (16) The pump device is provided with a plurality of brake cylinders.
Each is connected in parallel by a branch passage, and
Of the decompression passage that further branches from the fork to reach the low-pressure source.
Each of which is provided with the electromagnetic hydraulic pressure control valve, and
Each of the passages is closer to the pump device than a branch point of the pressure reducing passage.
(1) to (1)
5) The brake fluid pressure control device (contract
Claim 7). In the brake fluid pressure control device described in this section
Has different hydraulic pressures for multiple brake cylinders.
Can be controlled. For example, one brake system
Electromagnetic pressure control valve corresponding to the Linda allows hydraulic fluid to flow out
Once the outflow is allowed, the brake cylinder
The pump device side and the electromagnetic hydraulic pressure control valve side from the corresponding throttle device
And a hydraulic pressure difference occurs. On the other hand, the electromagnetic pressure control valve
The hydraulic pressure difference before and after the throttle device that is not
Does not occur. Electromagnetic pressure control valve is not allowed to flow out
The hydraulic pressure of the brake cylinder is substantially equal to the discharge pressure of the pump device.
The hydraulic pressure control valve is in an outflow allowable state
The hydraulic pressure of the brake cylinder is equal to the discharge pressure of the pump device.
It will be lower. And the brake cylinder
The difference between the hydraulic pressure and the discharge pressure of the pump device is
It depends on the magnitude of the supplied electric energy. did
As a result, the discharge pressure of the pump
To the largest (or more) of the hydraulic pressures
Control to the size corresponding to each of the other brake cylinders
Control the electrical energy to the corresponding electrohydraulic control valve
Control the hydraulic pressure of multiple brake cylinders independently of each other
You can do it. (17) The control device controls the electric motor to a plurality of
Control based on the maximum value of the target hydraulic pressure of the rake cylinder
(16) including the motor control device corresponding to the maximum target hydraulic pressure to be controlled
A brake fluid pressure control device as described in the above. For example, pumping
Electric drive so that the output pressure is the same as the maximum value of the target hydraulic pressure
The motor is controlled and, if necessary, an electrohydraulic control valve
If multiple brake systems are activated,
The hydraulic pressure of all the cylinders can be brought close to the target hydraulic pressure.
You. For electric motors, the discharge pressure of the pump
It is also possible to control so that it is larger than the maximum value by the margin value.
It is possible. In this case, the brake with the maximum target hydraulic pressure
The electromagnetic hydraulic pressure control valve corresponding to the
It is necessary to improve the hydraulic pressure control accuracy.
There are many. (18) The pump device is provided with a plurality of brake cylinders.
Each is connected in parallel by a branch passage, and
Of the decompression passage that further branches from the fork to reach the low-pressure source.
Each is provided with the electromagnetic hydraulic pressure control valve, and
The hydraulic pressure control device controls the pressure reduction of each of the branch passages.
Provided on the pump device side from the branch point of the passage.
Of the hydraulic fluid discharged from the pump
Inflow allowed state to allow inflow into each of the da
Pump shut-off valve that can be switched between
The control device may include a plurality of brake cylinders.
The required pressure reduction gradient of the hydraulic pressure of some of the brake cylinders is
When the brake pressure is equal to or higher than the predetermined set pressure reduction gradient, another brake
The required hydraulic pressure change gradient of the hydraulic pressure of the
Pressure boost side, some brake cylinders
A pump that switches the corresponding pump shutoff valve to the inflow blocking state
Any of paragraphs (1) to (17) including the shut-off valve control means
The brake fluid pressure control device according to claim 1 (claim 8). This section
In the brake fluid pressure control device described in
The throttle device according to the above (16) in a state where the valve is allowed to flow.
Perform the function of Pump shut-off valve is kept in the inflow allowable state
The hydraulic pressure control valve is controlled in the
Can be reduced, and the hydraulic pressure of multiple brake cylinders
It can be controlled vertically. On the other hand, the required decompression gradient is
For brake cylinders with a set pressure reduction gradient or higher,
The shutoff valve is switched to the inflow blocking state
When the pump is shut off from the pump device,
The pressure is reduced by control. As described above, the pump shutoff valve
The brake cylinder can be depressurized even when the
Function, but especially when a large decompression gradient is required
Is difficult to meet such demands, causing a delay in decompression.
I will. Therefore, operation from the pump device by the pump shutoff valve
The inflow of liquid is cut off, the decompression gradient is increased, and the decompression is delayed.
Is suppressed. Pump shut-off valve
It is necessary to control the hydraulic pressure of the hydraulic fluid supplied to the key cylinder.
Therefore, a simple solenoid on-off valve is sufficient. Note that the holding control
If there is an elephant brake cylinder,
For the cylinder, both from the pump device and the low pressure source
It is desirable to shut off. To keep fluid pressure constant and stable
The hydraulic fluid outflow and inflow in the brake cylinder
It is desirable to prevent it. In this case,
If both the shutoff valve and the electromagnetic pressure control valve are
You can easily achieve your goals. (19) The pump device has a small upper limit discharge pressure and a discharge flow.
Large-volume low-pressure pump and large maximum discharge pressure discharge flow
(1) to (18)
The brake fluid pressure control device according to any one of the preceding claims. Pump device
Include both low-pressure and high-pressure pumps.
If the pump device is relatively lightweight and inexpensive,
And the requirements of the discharge flow rate and discharge pressure can be satisfied. (20) Brake fluid for controlling brake cylinder fluid pressure
Pressure control device that satisfies a predetermined holding condition.
Control to maintain the brake cylinder fluid pressure in the event of a shock
Means and the driver keeps holding the brake cylinder hydraulic pressure.
If it is estimated that
A brake fluid pressure control device including a holding condition reducing means. Security
The driver wants to continue maintaining the hydraulic pressure
Includes means for estimating retention continuity
be able to. As mentioned above, when the vehicle is stationary
If the required fluid pressure change gradient is small,
It is presumed to be desired, and any one of paragraphs (7) to (11)
As described above, the holding conditions are relaxed. Conventional break
In the hydraulic control system, if it is not
Performing the holding control is also included in the relaxation of the holding condition. Ma
In addition, the brake fluid pressure control device
As described above, control of the pump device dedicated to pressure increase and pressure reduction
Control by controlling the electromagnetic hydraulic pressure control valve.
Control by adding the control of the pressure increasing electromagnetic hydraulic pressure control valve.
Even the control of the pressure increasing pump and the pressure reducing pump
May be controlled by the Furthermore, pressure increase
Control by controlling the on / off solenoid on-off valve
It may be.

[0004]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, claims 1, 2, 5 to 8 will be described.
A brake device provided with a brake fluid pressure control device as one embodiment common to the invention according to the present invention will be described in detail with reference to the drawings. In FIG. 3, reference numeral 10 denotes a brake pedal as a brake operating member, and 12 denotes a master cylinder. The master cylinder 12 is of a tandem type having two pressurizing chambers. One of the pressurizing chambers is connected to a wheel cylinder 18 of the left front wheel 16 via a liquid passage 14, and the other pressurizing chamber is connected to the other pressurizing chamber. The wheel cylinder 24 of the right front wheel 22 is connected via the liquid passage 20. In the present embodiment, one wheel cylinder is connected to one pressurizing chamber. In the middle of the liquid passages 14 and 20,
Master shutoff valves 26 and 28 are provided, respectively. The master shutoff valves 26 and 28 can be switched between a shutoff state in which the wheel cylinder is shut off from the master cylinder 12 and a communication state in which the wheel cylinder communicates with the master cylinder 12 by turning on and off the coil. A normally open valve that is shut off by supplying current during hydraulic pressure control, but is kept open by not supplying current during non-hydraulic pressure control. Returned to state.

[0005] The brake device is provided with a pump device 30. The pump device 30 includes a master reservoir 31 as a low pressure source, two pumps 32 and 34, a check valve 35,
36 and the like. The two pumps 32, 34
As shown in the figure, one of the pumps 32 is arranged in parallel with each other, and one of the pumps 32 has a large maximum discharge pressure and a small maximum discharge amount per unit time.
High-pressure pump 32) and the other pump 34
Is a low-pressure large-capacity gear pump (hereinafter, referred to as a low-pressure pump 34) having a small maximum discharge pressure and a large maximum discharge amount. The high-pressure pump 32 is operated by a high-pressure motor 38, and the low-pressure pump 34 is operated by a low-pressure motor 40. The check valve 35 is provided with a low-pressure pump 34.
The check valve 36 prevents the discharge pressure of the high-pressure pump 32 from acting on the low-pressure pump 34.
Further, although not shown, the low-pressure pump 34 and the high-pressure pump 3
In parallel with each of the pumps 2, there is provided a relief valve for setting the maximum discharge liquid pressure of each pump as a relief pressure. By controlling the low-pressure motor 40 and the high-pressure motor 38, it is possible to adjust the discharge pressure and the discharge flow rate of the working fluid discharged from the pump device 30 including the low-pressure pump 34 and the high-pressure pump 32. It is not essential that both the low-pressure pump 34 and the high-pressure pump 32 be gear pumps, and at least one of them may be a plunger pump. If the check valve 36 is an electromagnetic on-off valve, the low-pressure pump 34
, The wheel cylinder hydraulic pressure can be controlled.

[0006] A pump passage 42 extends from the discharge side of the pump device 30. The pump passage 42 is branched from the middle, and at the tip of each of the branch passages 44, the wheel cylinders 18 and 24 of the left and right front wheels 16 and 22 and the wheel cylinders 5 of the left and right rear wheels 46 and 48 are respectively provided.
0, 52 are attached. In the pump device 30,
The wheel cylinders 18, 24, 50, 52 are connected in parallel. In the middle of each of the branch passages 44, a pump cutoff valve 54 is provided to connect or cut off the wheel cylinder and the pump device 30. The pump cutoff valve 54 is a normally open valve that is kept open when no current is supplied. Further, the wheel cylinders 18 and 2 are supplied from the pump cutoff valve 54 in the branch passage 44 on the front wheel side.
The pressure reducing passage 56 extends from the branch point 55 on the fourth side to the master reservoir 3.
The pressure reducing passage 56 is provided with a pressure reducing electromagnetic hydraulic pressure control valve 58. Similarly, a pressure reducing passage 60 is extended from the pump cutoff valve 54 in the branch passage 44 on the rear wheel side to the master reservoir 31 from a branch point 59 on the wheel cylinders 50 and 52 side. A hydraulic control valve 62 is provided.
The depressurizing electromagnetic hydraulic control valves 58 and 62 will be described later.

As described above, in this embodiment, since the pump cutoff valve 54 is provided in each of the branch passages 44, it is possible to control the hydraulic pressures of the wheel cylinders 18, 24, 50, 52 to different magnitudes. Becomes possible. When the pump cutoff valve 54 is in the open state, it has a function as a throttle device, so that a difference in hydraulic pressure before and after the pump cutoff valve 54 is allowed. Since the pressure-reducing electromagnetic hydraulic pressure control valves 58 and 62 are provided on the wheel cylinder side of the pump device 54, the hydraulic pressure of the wheel cylinder can be controlled independently. That is, the hydraulic pressure on the wheel cylinder side of the pump cutoff valve 44 in the branch passage 44 is increased by the control of the pressure reducing electromagnetic hydraulic pressure control valves 58 and 62.
The hydraulic pressure on the wheel cylinder side can be independently controlled by controlling the pressure-decreasing electromagnetic hydraulic pressure control valves 58 and 62.

The wheel cylinders 18 and 24 have
Although both the master cylinder 12 and the pump device 30 are connected, the wheel cylinders 50 and 52 are connected to the pump device 30 but are not connected to the master cylinder 12. In other words, the pressure reducing electromagnetic hydraulic control valve 5 for the master pressure operated wheel cylinders 18, 24 connected to both the master cylinder 12 and the pump device 30.
Reference numeral 8 denotes a normally closed valve, and the pressure-reducing electromagnetic hydraulic control valve 62 for the power-pressure operated wheel cylinders 50 and 52 which are not connected to the master cylinder 12 but are connected to the pump device 30 is normally opened. In the present embodiment, the depressurizing electromagnetic hydraulic pressure control valve 58 corresponding to the master pressure operating wheel cylinders 18 and 24 is a normally closed valve, and the depressurizing electromagnetic hydraulic pressure control valve 62 corresponding to the power pressure operating wheel cylinders 50 and 52. By making the valve normally open, it is possible to operate the brake when the electric system is abnormal while preventing dragging.

In the middle of the liquid passage 20, a stroke simulator 70 is provided.
4, 50, 52 are disconnected from the master cylinder 12 and connected to the pump device 30, the brake pedal 10
Extremely short strokes are avoided. The stroke simulator may be provided on the liquid passage 14 side, between the brake pedal 10 and the master cylinder 12, or at two or more of these three places.
Also, a stroke sensor 71 for detecting the stroke of the brake pedal 10, a master pressure sensor 72 for detecting the hydraulic pressure of the master cylinder 12, a pump pressure sensor 74 for detecting the discharge pressure of the pump device 30, and the wheel cylinders 18, 2
Wheel cylinder pressure sensors 75 to 78 for detecting hydraulic pressures of 4, 50 and 52 are provided, respectively. Although described later, it is not essential to provide both the stroke sensor 71 and the master pressure sensor 72, and only one of them may be provided.

The pressure reducing electromagnetic hydraulic pressure control valve 58 shown in FIG.
It includes a seating valve 82 and an electromagnetic driving force generator 84. The seating valve 82 includes a valve 90 and a valve seat 9.
2 and an electromagnetically energized member 94 that moves integrally with the valve 90
And a spring 96 as an elastic member as an urging device for urging the electromagnetic urging member 94 in a direction in which the valve element 90 is seated on the valve seat 92. The electromagnetic driving force generating device 84 includes a coil 100, a resin holding member 102 that holds the coil 100, a first magnetic path forming body 104,
And a second magnetic path forming body 106. When the coil 100 is excited, a magnetic field is formed. Most of the magnetic flux
It passes through the first magnetic path forming body 104, the electromagnetically driven body 94, an air gap between the electromagnetically driven body 94 and the second magnetic path forming body 106, and the second magnetic path forming body 106.

If the current supplied to the coil 100 is changed, the magnetic force acting between the electromagnetically-urged member 94 and the second magnetic path forming member 106 changes. The magnitude of this magnetic force is
Increases with the magnitude of the current supplied to the coil 100,
The relationship between the current and the magnetic force can be known in advance.
Therefore, by continuously changing the supply current in accordance with the relationship, the force for urging the electromagnetically energized member 94 (the electromagnetically energized member 94 of the magnetic force described above is applied to the second magnetic path forming member 106). This force is referred to as an electromagnetic driving force Fs in order to be distinguished from the urging force of the spring 96. The electromagnetic driving force is a force in the opposite direction to the urging force Fk of the spring 96. This is a force in a direction in which the child 90 is separated from the valve seat 92.).

As described above, the depressurizing electromagnetic hydraulic control valve 58
The electromagnetic drive force Fs and the urging force Fk of the spring 96 act on the input port 108 and the output port 1 in the direction in which the valve element 90 is separated from the valve seat 92.
A differential pressure acting force Fp corresponding to the hydraulic pressure difference between the pressure difference 09 and the pressure difference acts on the pressure difference. The state where the sum of the electromagnetic driving force Fs and the differential pressure acting force Fp is larger than the urging force Fk of the spring 96 (Fs + Fp> F)
In k), the open state in which the valve element 90 is separated from the valve seat 92 is maintained. On the contrary, when the sum of the electromagnetic driving force Fs and the differential pressure acting force Fp is smaller than the urging force Fk of the spring 96 (Fs + Fp <Fk), the valve 90 is closed to be seated on the valve seat 92. Will be kept. The spring 96 has a large urging force Fk (greater than the maximum output hydraulic pressure of the pump device 30). Therefore, when the electromagnetic driving force is zero, the spring 96 is kept closed. 58 is a normally closed valve.

In this embodiment, the current supplied to the coil 100 of the pressure reducing electromagnetic hydraulic pressure control valve 58 is continuously controlled, and the hydraulic pressure of the wheel cylinders 18 and 24 is controlled. The differential pressure between the input port 108 and the output port 109 of the pressure reducing electromagnetic hydraulic control valve 58 corresponds to the differential pressure between the hydraulic pressure of the wheel cylinders 18 and 24 and the hydraulic pressure of the master reservoir 31. The hydraulic pressure of the wheel cylinder 1 can be regarded as atmospheric pressure.
The size corresponds to the hydraulic pressure of 8, 24. Therefore,
By controlling the electromagnetic driving force Fs, the differential pressure acting force Fp can be controlled and the wheel cylinder hydraulic pressure can be controlled. If the electromagnetic driving force is increased, the hydraulic pressure of the wheel cylinders 18 and 24 can be increased. Is reduced. The current supplied to the coil 100 is controlled so that the wheel cylinder hydraulic pressure approaches the target hydraulic pressure.

The pressure reducing electromagnetic hydraulic control valve 62 shown in FIG.
As with the pressure reducing electromagnetic hydraulic pressure control valve 58, the seating valve 1
30 and an electromagnetic driving force generator 132.
The seating valve 130 includes a valve seat 134, a valve element 136 provided on the valve seat 134 so as to be able to be seated and separated, and a valve element 136.
138 as an elastic member as a biasing device for biasing the valve 136 away from the valve seat 134, and a valve element 136
, And a driven member 142 that is driven by an electromagnetic force. The drive member 140, the valve element 136, and the electromagnetically biased member 142 are integrally movable.

The electromagnetic driving force generator 132 includes a coil 14
4, a holding member 145 for holding the coil 144, a first magnetic path forming member 146, and a second magnetic path forming member 148 fixed to the main body of the pressure reducing electromagnetic hydraulic pressure control valve 62.
When the coil 144 is excited, the first magnetic path forming body 146,
A magnetic field passing through the electromagnetic biased member 142, a gap between the electromagnetic biased member 142 and the second magnetic path forming member 148, and the second magnetic path forming member 148 is formed, and the electromagnetic biased member 142 is moved to the second position. An electromagnetic driving force in a direction to approach the magnetic path forming member 148 is generated. When the electromagnetic biasing member 142 is moved closer to the second magnetic path forming member 148 by the electromagnetic driving force, the valve element 136 is actuated.
Is brought closer to the valve seat 134. When the electromagnetic driving force is reduced to zero, the valve 136 is separated from the valve seat 134 by the urging force of the spring 138, and is kept in the open state.

In the pressure reducing electromagnetic liquid pressure control valve 62, the electromagnetic driving force Fs is equal to the differential pressure acting force Fp and the spring 13
8 (Fs <Fp + F)
k) is kept open, but can be neglected because the biasing force of the spring 138 is very small. When the electromagnetic driving force Fs is zero, the electromagnetic driving force Fs is kept open, and the pressure reducing electromagnetic hydraulic control valve 62 is a normally open valve. On the contrary, the electromagnetic driving force Fs and the differential pressure acting force Fp and the spring 13
8 (Fs> Fp + Fk)
) Is kept closed. By reducing the electromagnetic driving force,
The hydraulic pressure of the wheel cylinders 50, 52 can be reduced. In the present embodiment, by controlling the supply current, the wheel cylinder fluid pressure approaches the target fluid pressure,
Controlled.

The hydraulic brake device includes PU152, R
AM 153, ROM 154, input unit 155, output unit 15
6 is provided with a brake fluid pressure control device 160 mainly composed of a computer. Brake fluid pressure control device 16
0 input section 155, the stroke sensor 7
1, a master pressure sensor 72, a pump pressure sensor 74, wheel cylinder pressure sensors 75 to 78, a wheel speed sensor 162 to 165 for detecting the rotation speed of each wheel, and a brake switch for detecting that the brake pedal 10 is depressed. 166, a throttle sensor 168 as an accelerator operation state detecting device for detecting whether or not an accelerator pedal (not shown) is depressed, a steering angle sensor 170 for detecting a steering angle of a steering wheel not shown, and the brake device are mounted. A yaw rate sensor 172 for detecting the yaw rate of the vehicle that has been driven is connected, and a drive control device 174 that controls a drive source of a vehicle on which the brake device is mounted is connected. The output unit 156 is connected to the coils of the respective electromagnetic control valves via a drive circuit (not shown), and the high-voltage motor 38 and the low-voltage motor 40 are connected via drive circuits 176 and 178, respectively. . The ROM 154 includes a control program for the electromagnetic hydraulic pressure control valve and the like shown in the flowchart of FIG. , A vehicle stability control program, a pump motor control program, and various tables such as tables represented by the maps of FIGS.

The depression force of the brake pedal 10 is obtained based on the detection results of the stroke sensor 71 and the master pressure sensor 72. Due to the influence of the first fill, a delay in increasing the hydraulic pressure of the master cylinder 12 occurs at the beginning of the depression of the brake pedal 10. Therefore, in the low pressure region, the pedaling force is obtained based on the detection result of the stroke sensor 71, and in the high pressure region, the pedaling force is obtained based on the detection result of the master pressure sensor 72. Also,
When an abnormality occurs in one of the stroke sensor 71 and the master pressure sensor 72, the pedaling force is detected based on the other detection result. Further, wheel speed sensors 162 to 16
5 based on the wheel speeds detected by the control unit 5 and the estimated vehicle speed obtained based on the wheel speeds.
The braking slip states of 22, 46, and 48 are acquired, and antilock control is performed based on the braking slip states.
In addition, a change speed per unit time of the estimated vehicle body speed acquired based on the wheel speed is set as the actual acceleration. In the present embodiment, the wheel speed sensors 162 to 165 also serve as acceleration sensors. Further, the steering angle sensor 170,
Vehicle stability control is performed based on a detection result or the like detected by the yaw rate sensor 172.

The drive control device 174 supplies information indicating the magnitude of the drive torque applied to the vehicle. The drive source of the vehicle includes at least one of an engine as an internal combustion engine and an electric motor, and the sum of these drive torques is used as the drive torque applied to the vehicle. Also,
Although not shown, the drive circuits 176 and 178 include a control drive circuit and an applied voltage increase drive circuit. Usually, the voltage controlled by the control drive circuit is a high-voltage / low-voltage motor. When the required hydraulic pressure increase gradient is larger than the set pressure increase gradient, a voltage larger than the battery voltage is applied through the applied voltage increase drive circuit. The applied voltage increase drive circuit can be, for example, an electric circuit including a switch such as a coil, a capacitor, and a transistor, a DC-DC converter, or a boost converter.

The operation of the brake device configured as described above will be described. When the brake pedal 10 is depressed, a normal braking brake pressure control program is executed. A target wheel cylinder hydraulic pressure (hereinafter, simply referred to as a target hydraulic pressure) is obtained by executing the normal brake-time brake hydraulic pressure control program. And
The pump device 30 and the pressure-reducing electromagnetic hydraulic pressure control valves 58 and 62 are controlled so that the difference between the target hydraulic pressure and the actual wheel cylinder (hereinafter, simply referred to as the actual hydraulic pressure) is reduced.
In the present embodiment, the control of the pump device 30 and the pressure-reducing electromagnetic hydraulic pressure control valve
8 and 62 (by controlling the low-voltage motor 40 and the high-voltage motor 38 and by controlling the current supplied to the coils 100 and 144).
The hydraulic pressures 0 and 52 are commonly controlled.

When the braking slip becomes excessive with respect to the road surface friction coefficient, antilock control is performed. Each wheel 16,
The wheel cylinders 18, 24, 50, 5 are controlled so that the braking slip state of the wheel cylinders 22, 46, 48 is maintained in an appropriate state.
The second target hydraulic pressure is obtained by executing the antilock control program. In the present embodiment, the master shutoff valves 26 and 28 are switched to the shutoff state, and the pump device 30
The electromagnetic pressure control valves 58 and 62 for pressure reduction are controlled, and the pump cutoff valve 54 is controlled. The pump shut-off valve 54 is kept closed when rapid pressure reduction control and holding control are performed, and is kept open when gentle pressure reduction control and pressure increase control are performed.

When the turning state of the vehicle exceeds the set state, vehicle stability control is performed. By executing the vehicle stability control program, the steering angle sensor 17
0, when the spin value and the drift out value acquired based on the detection result of the yaw rate sensor 172 exceed predetermined set values SV _S and SV _D , a yawing moment in the direction of suppressing the spin and drift out is generated. Thus, the target hydraulic pressure of each wheel cylinder is determined. In the present embodiment, the pump device 3
0, while controlling the depressurizing electromagnetic hydraulic pressure control valves 58 and 62, the pump cutoff valve 54 is controlled.

When the operation speed of the brake pedal 10 is higher than a predetermined set speed, emergency braking brake assist control is performed. By executing the brake assist control program at the time of emergency braking, each wheel cylinder 1
The target hydraulic pressures of 8, 24, 50, and 52 are determined to have magnitudes corresponding to the operation speed. The magnitude of the target hydraulic pressure of each wheel cylinder is the same.

When the hydraulic pressure control is completed, the master shut-off valves 26 and 28 are returned to the communicating state, and the current supplied to the coils 100 and 144 of the pressure reducing electromagnetic hydraulic pressure control valves 58 and 62 becomes zero.
To be. The hydraulic fluid in the master pressure operated wheel cylinders 18 and 24 is returned to the master reservoir 31 via the master shutoff valves 26 and 28, and is supplied to the power pressure operated wheel cylinders 50 and 5.
The second hydraulic fluid is returned via the pressure reducing electromagnetic hydraulic pressure control valve 62. If an abnormality occurs in the electric system, the power supply is turned off. The master shutoff valves 26 and 28 are returned to the communicating state, the pressure reducing electromagnetic hydraulic pressure control valve 58 is returned to the disconnected state, and the pressure reducing electromagnetic hydraulic pressure control valve 62 is returned to the connected state. The master pressure operated wheel cylinders 18 and 24 are disconnected from the pump device 30 and communicate with the master cylinder 12. Since the pressure-reducing electromagnetic hydraulic pressure control valve 58 is in the shut-off state, the brake is operated by supplying the hydraulic fluid of the master cylinder 12 to the wheel cylinders 18 and 24.
The pump cutoff valve 54 is returned to the communication state, but the check valve 3
5 and 36 prevent the hydraulic fluid in the wheel cylinder from returning to the master reservoir 31 via the pump device 30.

The pump device 30 is controlled in accordance with the execution of a pump device control program. In the present embodiment, as shown in FIG. 13, the discharge pressure and discharge flow rate (abbreviated as discharge flow rate, etc.) of the working fluid discharged from the low-pressure pump 34 under the control of the low-pressure motor 40 are within the range of the region 1. Is controlled. By adding control of the high-pressure motor 38, the high-pressure pump 32 and the low-pressure pump 34
Is controlled within the range of region 2. The state represented by the range of the area 3 is the state of the low-voltage motor 40.
It can be realized by making the voltage applied to at least one of the motor and the high-voltage motor 38 larger than the battery voltage. In this case, the discharge flow rate of the pump device 30 is maximized. These are difficult to control.

In the present embodiment, when the common hydraulic pressure control such as the brake hydraulic pressure control during normal braking and the brake hydraulic pressure control during emergency braking is performed, the output from the pump device 30 detected by the pump pressure sensor 74 is output. At least one of the low-pressure motor 40 and the high-pressure motor 38 is controlled according to a map shown in FIG. 13 such that the hydraulic fluid discharge pressure (hereinafter, referred to as a pump pressure) approaches the target hydraulic pressure.
When the operation force of the brake pedal 10 is relatively small,
When the low-pressure motor 40 is controlled and the operating force increases,
The control of the high voltage motor 38 is also added. Also,
When independent hydraulic pressure control such as anti-lock control and vehicle stability control is performed, the pump pressure is controlled so as to approach the maximum value of the target hydraulic pressure of the wheel cylinders 18, 24, 50, and 52. If the pump pressure is set to the maximum value of the target hydraulic pressure, all the wheel cylinders 18, 24, 5
It is possible to make the hydraulic pressures of 0.5 and 52 close to the target hydraulic pressure. Further, when the required hydraulic pressure change gradient (the value obtained by subtracting the previous target hydraulic pressure from the current target hydraulic pressure) is equal to or greater than the set pressure increasing gradient, the voltage applied to the high-pressure motor 38 and the low-pressure pomotor 40 is reduced. It is higher than the battery voltage. The discharge capacity of the high-pressure pump 32 and the low-pressure pump 34 is maximized, and the pressure increase gradient of the wheel cylinder hydraulic pressure can be increased.

The pump device 30, the above-described pump cutoff valve 54, and the pressure reducing electromagnetic hydraulic pressure control valves 58 and 62 are controlled in accordance with the execution of a control program such as an electromagnetic hydraulic pressure control valve shown in the flowchart of FIG. Step 1 (hereinafter S
Abbreviated as 1. The same applies to other steps. )
In, it is determined whether or not the hydraulic pressure control is being performed. In the present embodiment, it is determined whether the target hydraulic pressure of at least one brake cylinder is greater than zero. As described above, the target hydraulic pressure is determined in accordance with the execution of the hydraulic pressure control program (which is a general term for a normal braking hydraulic pressure control program and the like).
It can be assumed that the hydraulic pressure is being controlled.

When the hydraulic pressure control is not being performed, it is detected whether or not a situation that can be expected to satisfy the pressure increasing condition occurs in the near future. In the present embodiment, when the brake pedal 10 is depressed, the pressure increasing condition is satisfied and the pressure increasing command is issued, so that it is detected whether or not there is a precursor to the brake pedal 10 being depressed. A state in which the accelerator pedal is not depressed while the vehicle is traveling downhill is a sign that the brake pedal 10 is depressed in the near future, and the low-voltage motor 40 is started. Thus, when the brake pedal 10 is actually depressed, it is possible to suppress a delay in braking effect. In the present embodiment, in S2 and S3, it is determined whether the vehicle is traveling on a downhill and whether the accelerator pedal is depressed. If both determinations are YES, the driving of the low-voltage motor 40 is started in S4,
If any one of the determinations is NO, in S5,
End processing is performed. S5 is also executed when the hydraulic pressure control ends, but is also executed before the hydraulic pressure control is started. The electromagnetic on-off valves 26 and 28 are returned to the open state, and the pump cutoff valve 54 is opened. The voltage applied to each of the coils 100 and 144 of the pressure reducing electromagnetic hydraulic control valves 58 and 62 is set to 0, and the operation of the pump device 30 is stopped. Further, initialization of each parameter and the like is performed. While the vehicle is traveling downhill and the accelerator pedal is not depressed, the low-pressure motor 40 is driven. , S5, the rotation of the low-voltage motor 40 is stopped.

The determination as to whether or not the vehicle is traveling on a downhill is performed by executing a program for determining whether the vehicle is traveling on a downhill as shown in the flowchart of FIG. In S21, the estimated vehicle speed is obtained based on the output results of the wheel speed sensors 162 to 165, and the change speed of the estimated vehicle speed per unit time is set as the actual acceleration α. In S22, the estimated acceleration α 'is obtained based on the information representing the driving torque F supplied from the driving control device 174. The estimated acceleration α ′ is a value obtained from the equation α ′ = (F−F ′) / M, where M is the vehicle weight, F ′ is the road load torque and is represented by a map shown in FIG. To
When the vehicle speed is high, the curve becomes large. This is because it is estimated that when the vehicle speed is high, the load received from the road surface increases, and the driving torque substantially decreases.

When the actual acceleration α and the estimated acceleration α ′ are the same, it is determined that the vehicle is traveling on a flat road surface, and when the actual acceleration α is smaller, it is determined that the vehicle is traveling uphill. If the actual acceleration α is larger, it is determined that the vehicle is traveling on a downhill. In S23, it is determined whether the actual acceleration α is larger than the estimated acceleration α ′. If it is larger, the determination is YES, and it is determined in S24 that the vehicle is traveling on a downhill. When the drive source includes both the engine and the electric motor, the drive torque F is acquired based on the operating state of both of them. When the drive source includes any one of them, the drive torque F Obtained based on state. If the low-pressure motor 40 is started while the vehicle is traveling on a downhill and the operation of the accelerator operation member is released, the wheel is immediately turned on when the brake pedal 10 is depressed as shown in FIG. The cylinder hydraulic pressure can be increased, and the pressure increase delay can be reduced.

On the other hand, when the hydraulic pressure control is being performed, the determination in S1 is YES, and in S6, it is determined whether or not the vehicle is in a stopped state. In this step, it is determined whether or not the estimated vehicle speed is lower than a predetermined set speed. At the beginning of the hydraulic pressure control, in most cases, the determination is NO, and S
At 7, the target hydraulic pressure determined by executing the hydraulic pressure control program or the like is read, and the required hydraulic pressure change gradient ΔPref
Is required. In S8, the required hydraulic pressure change gradient ΔPre
It is determined whether or not f is greater than a predetermined set pressure increasing gradient. When the brake pedal 10 starts to be depressed, the required hydraulic pressure change gradient ΔPref often becomes larger than the set pressure increasing gradient, so that the determination becomes YES. , And the pressure reducing electromagnetic hydraulic pressure control valves 58 and 62 are switched to the closed state. As shown in FIG. 14, when the applied voltage is increased, the low-voltage motor 4
0, the output torque of the high-pressure motor 38 increases, the discharge flow rate of the hydraulic fluid discharged from the pump device 30 increases, and the wheel cylinder hydraulic pressure can be rapidly increased. At the time of emergency braking, at the start of operation of the brake pedal 10, and the like, the required hydraulic pressure change gradient becomes equal to or greater than the set pressure increasing gradient,
In these cases, the pressure increase delay can be reduced. In the present embodiment, the set pressure increase gradient is set to a magnitude that cannot be realized in the control range in the area 2 in FIG. A voltage larger than the maximum voltage of the battery is applied while the required hydraulic pressure change gradient is large.

The low-voltage motor 40 and the high-voltage motor 3
By applying a voltage equal to or higher than the voltage of the battery to 8, the discharge flow rate of the working fluid from the pump device 30 can be increased, so that the low-pressure motor 40 and the high-pressure motor 38 do not have large capacities. , The pressure increase gradient can be increased. In order to widen the control range of the pump such as the discharge flow rate, it is necessary to increase the capacity of the pump motor, and it is inevitable to increase the cost.However, in this embodiment, the control range is not increased, but is increased. Only when a pressure increasing gradient is required, the discharge pressure of the hydraulic fluid discharged from the pump is made maximum. In this case, it is impossible to control the discharge amount or the magnitude of the discharge pressure itself. However, when a gradient higher than the set pressure increase gradient is required, it is sufficient if the pressure can be increased with a large gradient. The need to control size is low. By doing so, it is possible to increase the wheel cylinder hydraulic pressure at a gradient equal to or higher than the set pressure increasing gradient while avoiding an increase in cost. While the required pressure increase gradient is equal to or higher than the set pressure increase gradient, the applied voltage is not increased, but until the wheel cylinder fluid pressure reaches a predetermined set fluid pressure.
It can be made larger.

When the required hydraulic pressure change gradient is smaller than the set pressure increasing gradient, the determination in S8 is NO, and in S10, whether or not the hydraulic pressure control is one of antilock control and vehicle stability control. Is determined. Each of these controls is performed by each wheel cylinder 18, 2
The target hydraulic pressures of 4, 50, and 52 are not necessarily equal to each other, and are referred to as independent hydraulic pressure control. In the case other than these controls, that is, in the normal brake fluid pressure control and the emergency brake fluid pressure control, the target fluid pressures of the wheel cylinders 18, 24, 50, and 52 are the same. Is referred to as common hydraulic pressure control.

When the common hydraulic pressure control is being performed, S
The determination at 10 is NO, and the common hydraulic pressure control shown in the flowchart of FIG. 9 is performed at S11. S
At 31, the hydraulic pressure deviation ΔP, which is the difference between the target hydraulic pressure and the actual hydraulic pressure, is obtained.
It is determined to which of the pressure increasing region, the holding region (dead zone) and the pressure reducing region shown in FIG. 1 belongs. Hydraulic pressure deviation Δ
If P belongs to the holding region, holding control is performed in S34, if P belongs to the pressure increasing region, pressure increasing control is performed in S35, and if P belongs to the pressure decreasing region, pressure reducing control is performed in S36. In the common hydraulic control, the pump cutoff valve 54 is kept open.

In the pressure increase control, as shown in FIG.
By controlling at least one of the low-pressure motor 40 and the high-pressure motor 38, the discharge pressure of the pump device 30 is controlled so as to approach the target hydraulic pressure, and the depressurizing electromagnetic hydraulic pressure control valves 58 and 62 are kept closed. Dripping. In the holding control, the low-pressure motor 40 and the high-pressure motor 38 are stopped, and the pressure-reducing electromagnetic liquid pressure control valves 58 and 62 are kept closed. Since the hydraulic fluid is not supplied to the wheel cylinder, the hydraulic pressure of the wheel cylinder does not increase even if the pump cutoff valve 54 is not switched to the closed state. In the pressure reduction control, the low-pressure motor 40 and the high-pressure motor 38 are stopped, and the hydraulic pressure deviation ΔP is set to 0 by controlling the pressure-reducing electromagnetic hydraulic pressure control valves 58 and 62.
Can be approached.

As described above, in the common hydraulic pressure control, in the pressure increase control, the wheel cylinder hydraulic pressure is reduced by the pump device 3.
By controlling the discharge flow rate or the like of the working fluid output from 0, the hydraulic pressure is controlled. In the holding control, the pump device 30 is stopped and the pressure reducing electromagnetic hydraulic control valves 58 and 62 are closed. The hydraulic pressure is maintained by the switching, and in the pressure reduction control, the hydraulic pressure is controlled by controlling the pressure reducing electromagnetic hydraulic pressure control valves 58 and 62 in a state where the pump device 30 is stopped. As described above, in the common hydraulic pressure control, the hydraulic pressure of the wheel cylinder is controlled by controlling the operation state of the pump device 30 and the pressure reducing electromagnetic hydraulic control valves 58 and 6.
The control is not performed by the control of the pressure-increasing electromagnetic hydraulic pressure control valve and the pressure-decreasing electromagnetic hydraulic pressure control valve as in the conventional brake hydraulic pressure control device. Further, the pump cutoff valve 54 is kept open. In other words, the pump cutoff valve 54 is unnecessary, and if the pump cutoff valve 54 is not provided, the cost can be reduced accordingly.

On the other hand, when the antilock control and the vehicle stability control are being performed, the determination in S10 is YES, and the independent hydraulic pressure control shown in the flowchart of FIG. 10 is performed in S12. S4
1, each wheel cylinder 18, 24, 50, 5
In step S42, at least one of the low-pressure motor 40 and the high-pressure motor 38 controls the wheel cylinders 18, 24, 50, and 52.
Is controlled based on the maximum value Prefmax of the target hydraulic pressure. In the independent hydraulic control, the pump device 30 is kept in the operating state. In S43, the required hydraulic pressure change gradient Δ
It is determined whether there is a wheel cylinder whose Pref is smaller than the negative set gradient, that is, whether there is a wheel cylinder whose required pressure reduction gradient is larger than the set pressure reduction gradient.
If there is a wheel cylinder that requires rapid pressure reduction control, in steps S44 and S45, the pump cutoff valve 54 for that wheel cylinder is closed, and the pressure reduction electromagnetic hydraulic pressure control valves 62 and 58 are controlled. Thus, the actual hydraulic pressure approaches the target hydraulic pressure. In the independent hydraulic pressure control, at least one of the low-pressure motor 40 and the high-pressure motor 38 is controlled based on the maximum target hydraulic pressure. Is not supplied. Thereby, it is possible to reduce the pressure immediately.

On the other hand, for the wheel cylinders not subject to the rapid pressure reduction control, in S46, the hydraulic pressure deviation Δ
P is determined, and in S47 and S48, it is determined whether the hydraulic pressure deviation ΔP belongs to the pressure increasing region, the holding region, or the pressure reducing region. As shown in FIG. 11, in the case of belonging to the pressure increasing region, in S49, the pump shutoff valve 54 is kept open, and the electromagnetic pressure control valves 58, 62 for pressure reduction are controlled to thereby control the actual hydraulic pressure. Is brought close to the target hydraulic pressure. As described above, since the hydraulic fluid having the maximum target hydraulic pressure is supplied from the pump device 30, the pressure reducing electromagnetic hydraulic control valves 58 and 62 are provided.
May need to be controlled. In some cases, the depressurizing electromagnetic hydraulic control valves 58 and 62 are kept closed.
If it belongs to the holding area, in S50, both the pump cutoff valve 54 and the pressure reducing electromagnetic hydraulic pressure control valves 62 and 58 are kept closed. By preventing the inflow and outflow of the hydraulic fluid in the wheel cylinder, it is possible to stably maintain the hydraulic pressure. If it belongs to the moderate decompression region, S
At 51, with the pump cutoff valve 54 kept in the open state, the control of the pressure-reducing electromagnetic hydraulic pressure control valves 62 and 58 causes
The actual hydraulic pressure is brought closer to the target hydraulic pressure.

As described above, in the independent hydraulic pressure control, the output hydraulic pressure of the pump device 30 is controlled to a magnitude corresponding to the maximum target hydraulic pressure. Blocked from 30. As a result, the hydraulic pressure can be reduced with a large gradient, and the pressure reduction delay can be reduced. Further, since the wheel cylinder for which the holding control is performed is shut off from both the pump device 30 and the master reservoir 31, it is possible to keep the hydraulic pressure constant. Further, the pump shutoff valve 54
Has a throttle function, it is allowed for a hydraulic pressure difference to occur between the brake cylinders.

If the vehicle has stopped, the determination in S6 becomes YES, and in S13, the stop control program shown in the flowchart of FIG. 12 is executed. In S61, one of pressure increase, hold, and pressure decrease
The threshold value for making one selection is set to a value EPS ′ larger than threshold value EPS. Then, in S62, the hydraulic pressure deviation is obtained, and in S63, 64, the pressure increase region,
It is determined whether the region belongs to the holding region or the decompression region. If it belongs to the pressure holding region, the holding control is performed in S65. If it belongs to the pressure reducing region, the pressure reducing control is performed in S66.
At 67, it is determined whether the wheel speed is equal to or less than a set speed that can be considered to be almost zero. If the speed is higher than the set speed, the pressure increase control is performed in S68. If the speed is lower than the set speed, the holding control is performed in S65. If the wheels are rotated while the brake pedal 10 is depressed while the vehicle is stopped, the following vehicle may collide when stopped by a stop signal or the like. However, in other cases, there is no need to increase the pressure, so that the hydraulic pressure is kept constant. In this way, by increasing the pressure only when it is really necessary and maintaining the holding state in other cases, it is possible to improve the brake feeling of the driver and reduce the energy consumption in the stopped state. .

As described above, in the present embodiment, the brake fluid pressure control device 160 and the master pressure sensor 72,
A control device is constituted by the stroke sensor 71, the pump pressure sensor 74, and the like. The motor control device according to claim 2 is configured by a portion of the control device that executes S8 and S9 of the brake fluid pressure control device 160 and the like. Further, the brake switch 166, the stroke sensor 71,
The hydraulic pressure control device 160 executes the normal braking brake hydraulic pressure control program and the emergency braking brake hydraulic pressure control program, and constitutes a pressure increasing command device including a portion for issuing a pressure increasing command. The pre-motor starting means is constituted by a portion that executes steps # 4 to # 4. The pre-motor starting means is also a motor starting means during downhill traveling. In addition, a part that executes S44 of the hydraulic pressure control device 160 and the like constitute a pump cutoff valve control unit.

In the above-described embodiment, in the stop state, the threshold EPS of the hydraulic pressure deviation ΔP when any one of pressure increase, pressure decrease, and holding is selected is increased. Is selected when the wheel speed is low, the threshold value may be increased only in the stopped state. If the threshold is increased in the stopped state,
Holding becomes easy (the dead zone is widened), and the same effect can be obtained. A similar effect can be obtained by performing the holding control when the required hydraulic pressure change gradient is equal to or smaller than the set change gradient during the common hydraulic pressure control. In S11, the common hydraulic pressure control represented by the flowchart in FIG. 16 is performed.

In S81, it is determined whether or not the required hydraulic pressure change gradient is within a set range.
, The holding control is performed. It is determined whether or not the required hydraulic pressure change gradient is caused by an unconscious change in the depression force of the brake pedal 10 by the driver.
If it is within the range of the change due to the unconscious change (lower threshold RPFL (t) to upper threshold RPFU (t)), the hydraulic pressure of the wheel cylinder changes according to the required hydraulic pressure change. They are not allowed to do so. The pump device 30 is stopped, the pump cutoff valve 54 is kept open, and the pressure-reducing electromagnetic hydraulic pressure control valves 58 and 62 are kept closed.

Next, in S83, it is determined whether or not the elapsed time since the holding control is performed has exceeded the set time Ts. Before the set time has elapsed, the setting range is S
At 84, (lower threshold value RPFL (1) -upper threshold value RPFU (1)) remains unchanged, but after the set time has elapsed, at S85, (lower threshold value RPFL (2)-) is reached.
Upper threshold value RPFU (2)). Lower threshold R
PFL (2) is smaller than the lower threshold RPFL (1), and the upper threshold RPFU (2) is higher
The value is larger than U (1). As a result, if the time during which the holding control is continuously performed is long, the set gradient is increased, so that the holding control is easily performed, and the frequency of the holding control is increased.

On the other hand, the gradient of the required hydraulic pressure change is within a set range (lower threshold value RPFL (t) to upper threshold value RPF).
If not (U (t)), the timer is reset in step S86, and t is set to 1. In step S87 and subsequent steps, the same control as in step S31 and subsequent steps is performed. In the present embodiment, the holding control unit according to claim 3 is configured by a portion that executes steps S81 to 85 of the brake fluid pressure control device 160, and the holding control unit according to claim 4 is configured by a portion that executes steps S83 to 85. A holding condition relaxing means is configured. In addition,
In S85, the lower threshold value RPFL (t) is decreased and the upper threshold value RPFU (t) is increased, but either one may be changed. Also in that case, the setting range can be expanded.

In the above-described embodiment, any one of pressure increase, pressure decrease, and holding is selected based on the hydraulic pressure deviation. However, the required hydraulic pressure gradient is also taken into consideration. Can be. One example is shown in FIG. In the present embodiment, even if the hydraulic pressure deviation is larger than the set deviation EPS, if the required hydraulic pressure change gradient is smaller than the set gradient, the holding control is selected instead of the pressure increase control, and the hydraulic pressure deviation is set to the negative set deviation. Even if it is smaller than (-EPS), if the required hydraulic pressure change gradient is larger than the set gradient, it is also possible to perform the holding control instead of the pressure reduction control. By doing so, the frequency of the holding control is increased, and the energy consumption can be reduced accordingly.
In cases other than the stop state, it is also possible to perform control in consideration of the required hydraulic pressure change gradient. Furthermore, the absolute value of the threshold value when the pressure increase is selected and the absolute value of the threshold value when the pressure decrease is controlled may be different.

In the above embodiment, the vehicle is driven downhill.
During operation, the operation of the accelerator operation member is released.
So that the low-voltage motor 40 can be started if
Was running downhill, and the slope of the slope was high.
It can be made to start when it is too hot. Slope
Gradient is obtained according to the difference between the actual acceleration and the estimated acceleration.
Can be Furthermore, simply operating the accelerator pedal
Start when the vehicle is released,
When the condition that is less than the stability start condition is satisfied
It can also be started. For example, vehicle
For stability control, see Spin Value, Drift
Out value is set value SVs, SV _DSmaller bee
Vehicle stability control start predicted set value SVs', SV
_D′, The low-voltage motor 40 must be started.
You can do it.

In addition, during the brake fluid pressure control at the time of normal braking, in a state where the holding control and the pressure reducing control are being performed, when a precursor to the pressure increasing control is detected, the low pressure motor 40 is started. Can also. During the hold control and the pressure reduction control, the low-voltage motor 40 and the high-voltage motor 38 are in a stopped state. In these cases, when a precursor to the pressure increase control is detected, the low-voltage motor 40 is started. If possible, the pressure increase delay can be reduced. For example, it is assumed that when the hydraulic pressure deviation ΔP becomes larger than a threshold value EPS ^{* which} is smaller than the threshold value EPS, there is a sign that a pressure increase command is issued. In this case, during the execution of S34, it may be determined whether or not the hydraulic pressure deviation ΔP has become larger than a threshold value EPS ^* smaller than the threshold value EPS.

Further, in the above embodiment, when the required pressure increase gradient is equal to or higher than the set gradient, the voltage applied to both the high-voltage motor 38 and the low-voltage motor 40 is set to be equal to or larger than the maximum voltage of the battery. However, when the low-voltage motor 40 switches from the non-operation state to the operation state, only the voltage applied to the low-voltage motor 40 may be increased. In this case, it can be increased by the set time, increased until the required pressure increase gradient becomes equal to or less than the set gradient, or increased until the required hydraulic pressure is reached. In this case, the operation start motor control program represented by the flowchart of FIG. 18 is executed by interruption every set time. In S101, it is determined whether or not the operation start control flag is set. If not, in S102, the low-voltage motor 4
It is determined whether 0 is switched from the inactive state to the active state. If the operation is started, the determination is YES
In S103, the operation start control flag is set, and in S104, a voltage higher than that of the battery is applied. In S105, it is determined whether or not a set time has elapsed since the applied voltage was increased. Before the elapse, the operation start control is continuously performed, but after the elapse, in S106, the operation start control is performed. The flag is reset. Thereafter, the pump device 30 is controlled in accordance with the execution of the above-described motor control program. The low-pressure motor 40 is used when the brake pedal 10 is switched from the non-operation state to the operation state, during the common hydraulic pressure control, and when the holding / pressure reduction control is switched to the pressure increase control.
The state is switched from the non-operation state to the operation state. In these cases, a large voltage is applied, and the operation delay of the low-pressure pump 34 can be reduced.

When the required pressure increase gradient is equal to or greater than the set pressure increase gradient, only the low-voltage motor 40 is in the operating state, and when the high-pressure motor 38 is in the non-operation state, the voltage applied to the low-voltage motor 40 is increased. When the voltage is increased and the high-voltage motor 38 is also in operation, the voltage applied to the high-voltage motor 38 may be increased. Further, it is not indispensable to apply a voltage higher than the voltage of the battery, and it is also possible to apply a voltage higher than that in the normal control. In this case, the driving circuits 176 and 178
May be a circuit that can apply a voltage of a predetermined magnitude that is larger than the upper limit value of the normal control range and equal to or less than the maximum voltage of the battery.

In the above embodiment, both the pre-pump start control and the applied voltage increase control are performed. However, it is not necessary to perform both of them, and only one of them may be performed. In addition, the pressure increase delay can be reduced. Further, it is not indispensable that all the controls of the preliminary pump start control, the applied voltage increase control, the control during stoppage, the common hydraulic control, and the independent hydraulic control are performed, and at least one control may be performed. When the independent hydraulic pressure control is not performed, it is sufficient if the pressure reducing electromagnetic hydraulic control valve is provided commonly to all the wheel cylinders 18, 24, 50, and 52, and the pump cutoff valve 54 is also unnecessary. It is.

Further, in the above embodiment, in the independent hydraulic pressure control, the pump device 30 is always controlled based on the maximum value of the target hydraulic pressure of the wheel cylinders 18, 24, 50, 52. However, when holding or depressurization is selected for all the wheel cylinders 18, 24, 50, and 52, the operation of the pump device 30 can be stopped. For example, FIG.
As shown in FIG. 9, in S121, a hydraulic pressure deviation ΔP is obtained. One of pressure increase, hold, and pressure reduction is selected for each wheel cylinder by comparing the hydraulic pressure deviation ΔP with the threshold value, and the control selected for all wheel cylinders in S122 is hold or pressure reduction. It is determined whether or not. In other words, it is determined whether there is one or more wheel cylinders for which pressure increase has been selected.
If there is one or more wheel cylinders for which the pressure increase control has been selected, in S123, the pump device 30 is controlled based on the maximum value of the target hydraulic pressure as in the case described above.
If there is no wheel cylinder for which the pressure increase control has been selected, in S124, the operation of the pump device 30 is stopped, and the pump cutoff valve 54, the pressure reducing electromagnetic hydraulic pressure control valve 5
The hydraulic pressure is controlled by the control of 8,62. As described above, in the case of the holding control, the pump cutoff valve and the electromagnetic pressure control valve for pressure reduction are both closed. The hydraulic pressure is controlled by controlling the depressurizing electromagnetic hydraulic control valve. According to the present embodiment, when holding or depressurization is selected for all wheel cylinders, the pump device 30
Is stopped, the energy consumption can be reduced accordingly.

Further, the threshold value and the like do not need to be the same on the pressure increasing side and the pressure decreasing side, and may be different from each other. The control mode is not limited to the above embodiment. Further, in the above embodiment, the pump device 30 is provided with both the low-pressure pump 34 and the high-pressure pump 32, but may be provided with one pump. Further, the brake fluid pressure control device may be capable of traction control. Further, the pump shutoff valve 5
The present invention can also be applied to a brake device not provided with 4 or a brake device including a pressure-intensifying electromagnetic hydraulic pressure control valve capable of controlling a hydraulic pressure according to supplied electric energy instead of a pump cutoff valve. Further, the master cylinder 12 need not be a tandem type as long as it has two pressurizing chambers, but the present invention is not limited to this example. Can be implemented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a control example of a pressure reducing electromagnetic hydraulic pressure control valve by a brake hydraulic pressure control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of the above control.

FIG. 3 is a circuit diagram of a brake device including the brake fluid pressure control device.

FIG. 4 is a view conceptually showing a structure of a pressure-reducing electromagnetic fluid pressure control valve 58 included in the brake device.

FIG. 5 is a view conceptually showing the structure of a pressure reducing electromagnetic hydraulic pressure control valve 62 included in the brake device.

FIG. 6 is a flowchart showing a brake fluid pressure control program stored in a ROM of the brake fluid pressure control device.

FIG. 7 is a flowchart showing the contents of execution of S2 in the above flowchart.

FIG. 8 is a table showing a map representing a relationship between a vehicle speed and a load load stored in a ROM of the brake fluid pressure control device.

FIG. 9 is a flowchart showing the content of execution of S11 in the above flowchart.

FIG. 10 is a flowchart showing the content of execution of S12 of the above flowchart.

FIG. 11 is a diagram showing the contents of execution of S12 in the above flowchart. .

FIG. 12 is a flowchart showing the content of execution of S13 of the above flowchart.

FIG. 13 is a diagram conceptually showing a control mode of a pump device by the brake fluid pressure control device.

FIG. 14 is a diagram illustrating an example of control of a pump motor by the brake fluid pressure control device.

FIG. 15 is a diagram showing an example of advance motor control by the brake fluid pressure control device.

FIG. 16 is a flowchart showing a part of a brake fluid pressure control program stored in a ROM of a brake fluid pressure control device according to another embodiment of the present invention. 6 is a flowchart showing the contents of the above.

FIG. 17 is a diagram showing a part of a brake fluid pressure control program stored in a ROM of a brake fluid pressure control device according to another embodiment of the present invention, and is another execution of S11 in the flowchart of FIG. It is a figure which shows the content of.

FIG. 18 is a flowchart showing a part of an operation start motor control program stored in a ROM of a brake fluid pressure control device according to another embodiment of the present invention.

FIG. 19 is a flowchart showing the contents of S12 of a brake fluid pressure control program stored in a ROM of a brake fluid pressure control device according to another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 30 pump device 32 high-pressure pump 34 low-pressure pump 38 high-pressure motor 40 low-pressure motor 58 depressurizing electromagnetic hydraulic pressure control valve 62 depressurizing electromagnetic hydraulic pressure control valve 74 pump pressure sensor 160 brake hydraulic pressure control device

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shinichi Soejima 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Shu Shimura 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F Terms (Reference) 3D048 CC05 HH15 HH18 HH26 HH42 HH50 HH53 HH56 HH66 RR06

Claims (8)

[Claims] 1. A pump device connected to a brake cylinder, the pump device including at least one set of a pump for discharging hydraulic fluid toward the brake cylinder and an electric motor for driving the pump, and a hydraulic fluid discharged from the brake cylinder A low-pressure source that accommodates
An electromagnetic hydraulic pressure control valve capable of controlling the hydraulic pressure of the brake cylinder to a magnitude corresponding to the supplied electric energy; And a control device including pressure reduction control means for controlling the pressure of the supplied electric energy to reduce the brake cylinder pressure. 2. The control device controls the electric motor such that when the required pressure increasing gradient of the brake cylinder is larger than a predetermined set pressure increasing gradient, the output torque is larger than when the required pressure increasing gradient is smaller. The brake fluid pressure control device according to claim 1, further comprising a motor control means. 3. The control device according to claim 1, wherein when the required hydraulic pressure change gradient of the hydraulic pressure of the brake cylinder is within a predetermined set range, the control device stops the electric motor and sets the electromagnetic hydraulic pressure control valve to the electromagnetic pressure control valve. 3. The brake fluid pressure control device according to claim 1, further comprising a holding control unit that switches to an outflow prevention state for preventing outflow of hydraulic fluid from the brake cylinder. 4. The brake fluid pressure control device according to claim 3, wherein the control device includes a holding condition relaxing means for widening the set range when the holding control time by the holding control means is longer than when the holding control time is short. 5. A pressure increasing command means for issuing a pressure increasing command to increase the brake cylinder hydraulic pressure when a predetermined pressure increasing condition is satisfied, and said pressure increasing condition is satisfied. The brake fluid pressure control device according to any one of claims 1 to 4, further comprising: a pre-motor starting unit that starts the electric motor based on a precursor. 6. The brake fluid pressure control device according to claim 1, wherein an actual acceleration of the vehicle equipped with the brake fluid pressure control device is larger than an estimated acceleration estimated based on a driving torque of a driving source of the vehicle. A downhill traveling detection device that determines that the vehicle is traveling on a downhill, wherein the pre-motor starting means detects at least one of the precursors that a downhill traveling state has been detected by the downhill traveling detection device. 6. The brake fluid pressure control device according to claim 5, further comprising a motor starting means for driving the electric motor during downhill running. 7. A plurality of brake cylinders are connected to the pump device in parallel by branch passages, respectively.
The electromagnetic hydraulic pressure control valve is provided in each of the pressure reducing passages further branching from the respective branch passages and reaching the low pressure source, and each of the branch passages is provided at a portion closer to the pump device than a branch point of the pressure reducing passage. The brake fluid pressure control device according to any one of claims 1 to 6, wherein a throttle device is provided. 8. A plurality of brake cylinders are connected to the pump device in parallel by branch passages, respectively.
The electromagnetic hydraulic pressure control valve is provided in each of the pressure reducing passages further branching from the respective branch passages to the low pressure source, and the brake hydraulic pressure control device is configured to branch each of the branch passages into the pressure reducing passage. Pump shut-off valves which are respectively provided at portions closer to the pump device than the point and which can switch between an inflow permitting state in which the hydraulic fluid discharged from the pump is allowed to flow into each brake cylinder and an inflow blocking state in which the inflow is blocked. The control device, the required pressure reduction gradient of the hydraulic pressure of some of the brake cylinders of the plurality of brake cylinders is greater than or equal to a predetermined set pressure reduction gradient, the required hydraulic pressure of the other brake cylinder When the pressure change gradient is higher than the set pressure reduction gradient, the pump cutoff valve control switches the pump cutoff valves corresponding to some of the brake cylinders to the inflow prevention state. Brake fluid pressure control device according to any one of claims 1 comprises a stage 7.