JPH11208432A - Hydraulic control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease influence of viscosity of a working liquid on a hydraulic brake including a hydraulic control valve device. SOLUTION: A linear valve device is controlled so that actual hydraulic pressure of a wheel cylinder approaches target hydraulic pressure on a hydraulic brake including the linear valve device. A range between a pressure intensifying side threshold value and a pressure reduction side threshold value is decreased smaller than the case when viscosity of a working liquid is low in the case when viscosity of the working liquid is high in the case when pressure intensifying control is carried out in the case when hydraulic pressure deflection subtracting actual hydraulic pressure from target hydraulic pressure is higher than a pressure intensifying side threshold value DPLA and pressure reduction control is carried out in the case when it is lower than a pressure reduction side threshold value ADPUR. Consequently, pressure intensifying control or pressure reduction control is carried out in the case when neither pressure intensifying control nor pressure reduction control is carried out in the case when viscosity is low, and it is possible to decrease control delay of wheel cylinder hydraulic pressure by that amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device including a hydraulic control valve device.

[0002]

2. Description of the Related Art An example of the above-mentioned hydraulic pressure control apparatus is disclosed in
No. 39014. The hydraulic pressure control device described in this publication is provided between a high-pressure section, a low-pressure section, and a wheel cylinder, and allows the hydraulic fluid to flow from the high-pressure section to the wheel cylinder, and operates from the wheel cylinder to the low-pressure section. A hydraulic pressure control valve device that permits the outflow of liquid, and a deceleration deviation obtained by subtracting an actual deceleration from a target deceleration of a vehicle equipped with the hydraulic pressure control device is equal to or greater than a first threshold value. The actual deceleration is reduced by allowing the inflow of the hydraulic fluid to the wheel cylinder and allowing the outflow of the hydraulic fluid from the wheel cylinder when the hydraulic fluid is equal to or less than a second threshold smaller than the first threshold. Hydraulic pressure control means for approaching the speed. In this hydraulic pressure control device, the range between the first threshold value and the second threshold value is determined independently of the viscosity of the hydraulic fluid. There were problems such as becoming.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the influence of the viscosity of hydraulic fluid on hydraulic pressure control in a hydraulic pressure control device including a hydraulic pressure control valve device. That is. The above object is attained by providing a hydraulic control device having a structure of each of the following embodiments. In addition, each mode is divided into items, item numbers are assigned, and if necessary, the numbers of other items are cited and described in the same format as the claims. This is to clarify the possibility of adopting the features described in each section in combination. (1) A liquid provided between the high-pressure section, the low-pressure section, and the wheel cylinder to allow the hydraulic fluid to flow from the high-pressure section to the wheel cylinder or to allow the hydraulic fluid to flow from the wheel cylinder to the low-pressure section. A pressure control valve device, and a hydraulic pressure deviation related amount related to a hydraulic pressure deviation obtained by subtracting an actual wheel cylinder hydraulic pressure from a target hydraulic pressure of the wheel cylinder. The hydraulic pressure of the wheel cylinder is made closer to the target hydraulic pressure by allowing the inflow of the hydraulic fluid and permitting the outflow of the hydraulic fluid from the wheel cylinder when the hydraulic fluid is equal to or less than the second threshold smaller than the first threshold. A hydraulic pressure control device including a hydraulic pressure control means, wherein the hydraulic pressure control means changes a range between the first threshold value and the second threshold value according to a viscosity of the hydraulic fluid. Threshold change means Fluid pressure control device which comprises (Claim 1). In the hydraulic pressure control device according to the present mode, the range between the first threshold value and the second threshold value is changed according to the viscosity of the hydraulic fluid. When the viscosity is high, the range is smaller than when the viscosity is low. If the viscosity is low,
Neither pressure increase nor pressure reduction is performed because the hydraulic pressure deviation related amount is within the range, but if the range is reduced when the viscosity is high,
The pressure may be increased or decreased, and the control delay caused by the high viscosity can be reduced accordingly. Further, when the viscosity is low, that is, even when the viscosity is normal, the range between the first threshold value and the second threshold value can be set to an appropriate range. It is possible to suppress a decrease in control accuracy due to the difference. The hydraulic pressure deviation related amount is an amount related to the hydraulic pressure deviation obtained by subtracting the actual hydraulic pressure of the wheel cylinder from the target hydraulic pressure of the wheel cylinder. The value may be a value obtained by adding a value (the set value may be a positive value or a negative value), or a value obtained by dividing the hydraulic pressure deviation by the actual hydraulic pressure or the target hydraulic pressure. it can. In any case, when the hydraulic pressure deviation related amount is large, the actual hydraulic pressure is smaller than the target hydraulic pressure, and when the hydraulic pressure deviation related amount is small, the actual hydraulic pressure is larger than the target hydraulic pressure. In the hydraulic pressure control device described in this section, when the hydraulic pressure deviation related amount is equal to or larger than the first threshold value, the pressure increase control is performed by allowing the hydraulic fluid to flow into the wheel cylinder. The actual hydraulic pressure of the wheel cylinder is increased to approach the target hydraulic pressure. When the hydraulic pressure deviation related amount is equal to or less than the second threshold, the outflow of the hydraulic fluid from the wheel cylinder is permitted, so that the pressure reduction control is performed, and the actual hydraulic pressure is reduced. The range between the first threshold value and the second threshold value is changed according to the viscosity. However, when the range is changed, the second threshold value is kept constant and the first threshold value is changed. The first threshold value may be changed, the second threshold value may be changed while the first threshold value is kept constant, or both the first threshold value and the second threshold value may be changed. The influence of the viscosity of the hydraulic fluid on the hydraulic pressure control occurs both when the inflow of the hydraulic fluid into the wheel cylinder is permitted and when the outflow from the wheel cylinder is permitted. It is desirable to change both the thresholds. The first threshold value and the second threshold value may be changed continuously or stepwise according to the viscosity. A fluid pressure control device for permitting inflow of the hydraulic fluid when the fluid pressure deviation related amount is equal to or greater than the first threshold value, and blocking the inflow when the fluid pressure deviation related amount is smaller than the first threshold value; If there is an outflow control means that allows outflow when the threshold value is less than the threshold value and prevents outflow when the value is larger than the second threshold value, a range between the first threshold value and the second threshold value Can be referred to as a non-control range (control dead zone), a holding control range, and the like, and the threshold value changing unit can be referred to as a non-control range changing unit, a holding control range changing unit, and the like. If the non-control range is changed, the control range is changed, and therefore, it can be referred to as control range changing means. (2) The threshold value changing means reduces the range between the first threshold value and the second threshold value when the viscosity of the hydraulic fluid is high as compared with when the viscosity of the hydraulic fluid is low. Hydraulic control device. At least one of the pressure-increase-side threshold value lowering means for decreasing the first threshold value and the pressure-decrease-side threshold value increasing means for increasing the second threshold value is included in the threshold value changing means described in this section. included. (3) The hydraulic pressure control device according to the above mode (1) or (2), wherein the hydraulic pressure control unit includes a viscosity obtaining unit that obtains the viscosity of the hydraulic fluid. The viscosity of the hydraulic fluid can be obtained directly or indirectly based on the temperature of the hydraulic fluid or the like. As described in the specification of Japanese Patent Application No. 9-320690 previously filed by the present applicant and not yet published, the viscosity of the hydraulic fluid is related to the hydraulic pressure difference on both sides of the hydraulic control valve device. It can be directly obtained based on the differential pressure-related amount and the flow-related amount related to the flow rate of the working fluid.
Since the opening of the valve of the hydraulic pressure control valve device can be regarded as a throttle, the viscosity of the hydraulic fluid can be obtained according to Hagen-Poitouille's law based on the differential pressure-related amount and the flow rate-related amount. It is. The hydraulic pressure difference on both sides of the hydraulic pressure control valve device can be obtained, for example, by providing hydraulic pressure sensors on both sides. The flow rate of the hydraulic fluid flowing through the hydraulic pressure control valve device is, for example, such that the hydraulic pressure control valve device allows the flow of the hydraulic fluid at a flow rate corresponding to the magnitude of the supply power as described in the paragraph (5). In this case, it can be obtained based on the magnitude of the supplied power. In addition, the viscosity of the working fluid usually increases when the temperature of the working fluid is low. Therefore, the viscosity can be obtained indirectly based on the temperature of the working fluid. The temperature of the hydraulic fluid can be directly detected, or can be estimated based on the temperature of the engine cooling water or the temperature of the frictional engagement portion between the brake pad and the brake rotor.
As will be described later in the section of the preferred embodiment, the temperature of the engine cooling water and the ignition switch
Based on the elapsed time from N, the temperature of the hydraulic fluid of the hydraulic control device can be estimated, and the viscosity can be obtained based on the estimated temperature of the hydraulic fluid. (4) The hydraulic pressure control means allows the inflow when the hydraulic pressure deviation related amount reaches the first threshold value and reaches a third threshold value smaller than the first threshold value. An inflow control means for preventing the inflow when the hydraulic pressure deviation related amount reaches the second threshold, and allowing the outflow and setting a fourth threshold larger than the second threshold. An outflow control means for preventing the outflow when it has reached,
Hysteresis changing means for changing at least one of a difference between the first threshold value and the third threshold value and a difference between the second threshold value and the fourth threshold value in accordance with the viscosity of the hydraulic fluid The hydraulic pressure control device according to any one of the above items (1) to (3), including: (Claim 2). The pressure increase control is performed until the hydraulic pressure deviation related amount reaches the first threshold value and then reaches the third threshold value, and the pressure decrease control is performed until the hydraulic pressure deviation related amount reaches the fourth threshold value after reaching the second threshold value. Is performed. Hysteresis is given to the start and end of the pressure increase control and the start and end of the pressure decrease control, respectively, and at least one of the two hysteresis is changed according to the viscosity. As described above, since the range between the first threshold value and the second threshold value is reduced when the viscosity is high, it is preferable that the hysteresis is also reduced accordingly. When the viscosity is high, at least one of both hysteresis is reduced. Regardless of whether the range between the first threshold value and the second threshold value is large or small, if the above-mentioned hysteresis is the same, control accuracy may be reduced due to excessive control or the like. On the other hand, if the hysteresis is changed according to the range between the first threshold value and the second threshold value, it is possible to suppress a decrease in control accuracy. When at least one of the difference between the first threshold value and the third threshold value and the difference between the second threshold value and the fourth threshold value is changed, the difference corresponds to the changed one. There is a case where at least one of the third threshold value and the fourth threshold value changes in size before change and a case where it does not change. Since at least one of the first threshold value and the second threshold value is changed according to the viscosity,
If the hysteresis is changed accordingly, the third threshold value and the fourth threshold value can be kept unchanged.
Conversely, the hysteresis can be changed by changing at least one of the third threshold value and the fourth threshold value. (5) The hydraulic pressure control valve device controls the flow of the hydraulic fluid from the high-pressure section to the wheel cylinder and the flow of the hydraulic fluid from the wheel cylinder to the low-pressure section by a flow rate according to the magnitude of the supplied power. (1) wherein the hydraulic pressure control means includes a viscosity-related supply power control means that determines the supply power according to the hydraulic pressure deviation related amount and the viscosity of the working fluid. The hydraulic pressure control device according to any one of claims (4) to (4) (claim 3). In a hydraulic pressure control valve device in which the flow rate of the working fluid is increased when the supply power is large, the flow rate can be increased by increasing the supply power as compared to the case where the viscosity is high when the viscosity is high. Thus, the control delay caused by the above can be reduced. In addition, if the magnitude of the supplied power is changed according to the viscosity, it is possible to suppress a decrease in hydraulic pressure control accuracy due to the difference in the viscosity.

[0004]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a hydraulic control device according to an embodiment of the present invention will be described with reference to the drawings. The hydraulic braking device including the present hydraulic pressure control device is used for a hybrid vehicle including both an internal combustion engine and an electric motor as drive sources. The braking of the hybrid vehicle according to the present embodiment is performed by braking by a hydraulic braking device and regenerative braking by a regenerative braking device (not shown). The regenerative braking device is a device that causes the electric motor to function as a generator and stores the electric energy generated by the electric motor in a storage battery to brake the vehicle. When the storage battery is charged by an electromotive force (hereinafter simply referred to as regenerative electromotive force) generated in the electric motor when the rotating shaft of the electric motor is forcibly rotated by an external force, the electric motor is driven by the external force. And a braking force is generated. Part of the kinetic energy of the vehicle during braking is converted to electrical energy and stored in the storage battery, which not only can brake the vehicle but also reduce the consumption of electrical energy in the storage battery. It is possible to extend the distance that can be traveled without charging.

[0005] Braking force by regeneration (referred to as regenerative braking force)
Is not always constant. For example, the regenerative braking force tends to increase as the rotation speed of the rotating shaft of the electric motor increases. When the running speed of the vehicle is extremely low, the regenerative braking force becomes almost zero. In addition, when the capacity of the storage battery is completely filled, control for inhibiting the regeneration of energy is often performed in order to prevent deterioration of the storage battery due to overcharging, and in this case, a period during which the regeneration is prohibited is performed. During this time, the regenerative braking force becomes zero. On the other hand, the magnitude of the braking force of the vehicle needs to be controlled to a magnitude according to the intention of the driver, which is not directly related to the magnitude of the regenerative braking force. Therefore, the magnitude of the hydraulic braking force to be generated in the hydraulic braking device is a magnitude obtained by subtracting the regenerative braking force from the required braking force according to the intention of the driver.
Such control is referred to as regenerative braking cooperative control. The magnitude of the required braking force can be easily known from the braking operation status such as the operating force, the operating stroke, and the operating time of the brake operating member, and the information on the magnitude of the regenerative braking force can be obtained from the regenerative braking device.

As shown in FIG. 1, the hydraulic braking system includes a hydraulic pressure source including a master cylinder 12 with a booster, and a constant hydraulic pressure source 17 including a pump 13, an accumulator 14, a master reservoir 15, a relief valve 16, and the like. 18. The master cylinder 12 with a booster has two hydraulic chambers, and the constant hydraulic pressure source 17 is connected to one of the hydraulic chambers. When the brake pedal 19 is depressed, the depressing force is boosted using the hydraulic fluid of the constant hydraulic pressure source 17, and the hydraulic pressure corresponding to the boosted depressing force is applied to the two hydraulic fluids of the master cylinder 12 with the booster. Generated in the pressure chamber.
In the accumulator 14, the working fluid of the master reservoir 15 is pumped up by the pump 13 and stored. The accumulator 14 is provided with two pressure switches 20 and 21. One pressure switch detects that the hydraulic pressure stored in the accumulator 14 has become larger than the upper limit, and the other pressure switch has the other. The pressure switch is a switch that detects that the pressure has become smaller than the lower limit. Based on the operation of these pressure switches 20, 21, the pump 13
The hydraulic pressure of the working fluid stored in the accumulator 14 is maintained in a set range by controlling the motor that drives the motor. When the hydraulic pressure of the accumulator 14 becomes larger than the upper limit, the hydraulic fluid is returned to the master reservoir 15 via the relief valve 16.

A wheel cylinder 24 of a left front wheel 23 and a wheel cylinder 26 of a right front wheel 25 are connected to one hydraulic chamber of the master cylinder 12 with a booster via a liquid passage 22. In the liquid passage 22, an electromagnetic on-off valve 30,
An electromagnetic on-off valve 42, 44 is provided in the middle of a liquid passage 40 connecting the wheel cylinders 24, 26 and the master reservoir 15, respectively.

In the other hydraulic chamber, a liquid passage 48 is provided.
The wheel cylinder 50 of the left rear wheel 49 and the wheel cylinder 52 of the right rear wheel 51 are connected. In the middle of the liquid passage 48, a linear valve device 56, an electromagnetic on-off valve 58, and a proportioning valve 60 are provided in this order from the master cylinder 12 with the booster. Liquid passage 4
8, a hydraulic pressure sensor 62 is provided at a portion between the master cylinder 12 with the booster and the linear valve device 56, and a hydraulic pressure sensor 64 is provided at a portion between the linear valve device 56 and the electromagnetic on-off valve 58. Have been. The hydraulic pressure obtained by the hydraulic pressure sensor 62 is called an input hydraulic pressure Pin, and the hydraulic pressure obtained by the hydraulic pressure sensor 64 is called an output hydraulic pressure Pout1. The linear valve device 5 is controlled by the hydraulic pressure sensors 62 and 64.
The hydraulic pressure before and after 6 is detected. Hydraulic pressure sensors 62 and 6
4 is connected to the controller 66. As will be described later, the controller 66 controls the linear valve device 56 based on the output hydraulic pressure Pout1 detected by the hydraulic pressure sensor 64. An electromagnetic on-off valve 72 is provided in the middle of the liquid passage 70 connecting the wheel cylinders 50 and 52 and the master reservoir 15.

A liquid passage 76 is connected to a portion of the liquid passage 48 between the linear valve device 56 and the electromagnetic on-off valve 58. The liquid passage 76 is a passage that connects the linear valve device 56 and the wheel cylinders 24 and 26, and the liquid passage 7
In the middle of 6, an electromagnetic on-off valve 80 is provided. The electromagnetic on-off valve 80 is switched to the open state when regenerative braking cooperative control, antilock control, or the like is performed. On the wheel cylinders 24 and 26 side of the electromagnetic on-off valve 80, electromagnetic on-off valves 84 and 86 are provided, respectively. Liquid passage 7
6, a hydraulic pressure sensor 88 is connected to a portion between the electromagnetic on-off valve 80 and the electromagnetic on-off valves 84 and 86. The measurement result by the hydraulic pressure sensor 88 is defined as an output hydraulic pressure Pout2. The output hydraulic pressure Pout2 is used for monitoring whether the output of the hydraulic pressure sensor 64 is normal. When the value of the output hydraulic pressure Pout1 detected by the hydraulic pressure sensor 64 is different from the value of the output hydraulic pressure Pout2 when the electromagnetic on-off valve 80 is in the open state, the output of the hydraulic pressure sensor 64 may be abnormal. It is determined that there is sex. That is, when the electromagnetic on-off valve 80 is in the open state, the hydraulic pressure sensor 64 and the hydraulic pressure sensor 88 are in communication with each other, and when the hydraulic pressure sensors 64 and 88 are both normal, the output hydraulic pressure Pout1 and the output This is because the hydraulic pressure Pout2 should be substantially the same. In the present embodiment, the operator is notified of the fluid pressure sensor abnormality based on the determination result.
Along with or instead of this notification, control of the linear valve device 56 by the controller 66 may be prohibited. Each of these plural solenoid on-off valves 30, 3
The solenoids 2, 42, 44, 58, 72, 80, 84 and 86 are controlled based on a command from the controller 66.

A check valve 90 is provided in the middle of the bypass passage bypassing the electromagnetic on-off valve 58, and is provided in the middle of the bypass passages bypassing the electromagnetic on-off valves 84, 86, respectively. Is provided. These check valves 90, 92, and 94 are mounted in such a direction that the flow of the hydraulic fluid from the corresponding wheel cylinder toward the master cylinder 12 with the booster is allowed, but the flow in the opposite direction is prevented. These check valves 90, 9
2, 94, it is possible to quickly return the hydraulic fluid of the wheel cylinder to the master cylinder 12 with the booster when the depression of the brake pedal 19 is loosened while the electromagnetic on-off valves 58, 84, 86 are closed. Becomes
Each of the wheels 23, 25, 49, and 51 is provided with a wheel speed sensor 110 to 116 for detecting a rotation speed of the wheel. A braking slip state or the like is detected based on the wheel speeds detected by the wheel speed sensors 110 to 116.

FIG. 2 shows the linear valve device 5 shown in FIG.
6 is a system diagram schematically showing a configuration of FIG. The linear valve device 56 includes a pressure increasing linear valve 150, a pressure reducing linear valve 152, a pressure reducing reservoir 154, and a check valve 156, 1.
58. The pressure-increasing linear valve 150 is provided in the middle of the liquid passage 48, and the pressure-reducing linear valve 152 is connected to the liquid passage 1 that connects the liquid passage 48 and the pressure-reducing reservoir 154.
It is provided in the middle of 60. Booster linear valve 150
In the middle of the bypass passage for bypassing the check valve 156
However, the hydraulic fluid is allowed to flow from the wheel cylinder to the booster-equipped master cylinder 12, but is prevented from flowing in the opposite direction. Pressure reducing linear valve 1
In the middle of the bypass passage bypassing the check valve 52, the check valve 1
Numeral 58 allows the flow of the hydraulic fluid from the pressure reducing reservoir 154 to the master cylinder 12 with the booster, but prevents the reverse flow.

The decompression reservoir 154 stores the hydraulic fluid discharged from the wheel cylinder. The volume of the liquid storage chamber for storing the hydraulic fluid is the reservoir capacity, and the reservoir capacity is equal to the maximum amount of the hydraulic fluid that the pressure reducing reservoir 154 can store during one braking operation. In the present embodiment, the reservoir capacity is smaller than the sum of the capacities of the wheel cylinders 24, 26, 50, 52. Therefore, when the amount of hydraulic fluid stored in the pressure reducing reservoir 154 increases, it becomes impossible to reduce the wheel cylinder hydraulic pressure, that is, it becomes impossible to control the hydraulic pressure, and the regenerative braking force is set to zero. Here, the wheel cylinders 24, 2
The capacities of 6, 50, and 52 mean the maximum amount of hydraulic fluid that the wheel cylinder can accommodate from a non-operating state to an operating state.

The pressure-increasing linear valve 150 includes a seating valve 190 and an electromagnetic biasing device 194.
The seating valve 190 includes a valve 200 and a valve seat 202.
And the electromagnetically biased body 204 that moves integrally with the valve 200
And a spring 206 as an elastic member as an urging means for urging the electromagnetically energized member 204 in a direction in which the valve 200 is seated on the valve seat 202 (hereinafter, the valve 200 of the spring 206 is attached to the valve seat 202). (The biasing force in the seating direction is referred to as a spring biasing force). The electromagnetic urging device 194 includes a solenoid 210, a resin holding member 212 that holds the solenoid 210, a first magnetic path forming body 214, and a second magnetic path forming body 216. When a voltage is applied to both ends of the winding of the solenoid 210, a current flows through the winding of the solenoid 210 and a magnetic field is formed. Most of the magnetic flux is generated by the first magnetic path forming body 214,
It passes through the electromagnetically energized body 204, the air gap between the second magnetic path forming body 216 and the electromagnetically energized body 204 and the second magnetic path forming body 216. If the voltage applied to the winding of the solenoid 210 is changed, the magnetic force acting between the electromagnetically energized member 204 and the second magnetic path forming member 216 also changes. The magnitude of the magnetic force increases with the magnitude of the voltage applied to the winding of the solenoid 210, and the relationship between the applied voltage and the magnetic force can be known in advance. Therefore, by continuously changing the applied voltage according to the relationship,
The force for urging the electromagnetically energized body 204 (the force in the direction in which the electromagnetically energized body 204 is brought closer to the second magnetic path forming body 216 among the magnetic forces described above. (The electromagnetic driving force is a force in the direction opposite to the biasing force of the spring.). An engaging projection 220 is formed on a surface of the electromagnetically energized body 204 facing the second magnetic path forming body 216, and the engaging projection 220 is opposed to the engaging protruding body 204 of the second magnetic path forming body 216. An engagement recess 222 is formed in the portion where the engagement protrusion 220 and the engagement recess 222 are formed in accordance with a change in the relative position between the electromagnetic biased member 204 and the second magnetic path formation member 216. The area of the facing portion therebetween is changed.

Electromagnetic biasing member 204 and second magnetic path forming member 21
The magnetic resistance of the magnetic path formed by 6 changes depending on the relative position of the electromagnetically-urged member 204 and the second magnetic-path forming member 216 in the axial direction. More specifically, the electromagnetically biased member 2
If the relative position of the second magnetic path forming body 216 with respect to the axial direction changes, the minute gap between the fitting projection 220 of the electromagnetic biased member 204 and the fitting concave part 222 of the second magnetic path forming body 216 changes. The area of the cylindrical surfaces facing each other (parts of the outer peripheral surface of the fitting protrusion 220 and the inner peripheral surface of the fitting recess 222 that face each other) changes. If the electromagnetically energized body 204 and the second magnetic path forming body 216 simply face each other with a small gap between the end faces, the electromagnetically energized body 204 and the second magnetic path forming body 216 are opposed to each other. As the distance in the axial direction decreases, that is, approaching, the magnetic resistance decreases at an accelerating rate, and the magnetic force acting between them increases at an accelerating rate. On the other hand, in the pressure-intensifying linear valve 150 of the present embodiment, as the electromagnetically biased member 204 and the second magnetic path forming member 216 approach, the cylindrical shape of the fitting protrusion 220 and the fitting recess 222 is increased. While the surface area increases and the magnetic flux passing through the cylindrical surface increases, the magnetic flux passing through the air gap between the end face of the electromagnetically energized member 204 and the end face of the second magnetic path forming member 216 decreases. As a result, if the voltage applied to the solenoid 210 is constant within a range that is not so large, the magnetic force (electromagnetic driving force) that urges the electromagnetic biased body 204 in the direction of the second magnetic path forming body 216 becomes:
It is substantially constant irrespective of the relative position in the axial direction between the electromagnetically energized member 204 and the second magnetic path forming member 216. On the other hand, the urging force (urging force of the spring) for urging the electromagnetically energized body 204 by the spring 206 in a direction away from the second magnetic path forming body 216 is a combination of the electromagnetically energized body 204 and the second magnetic path forming body. It increases with approach to the H.216. Accordingly, an urging force (acting in accordance with the front-rear hydraulic pressure difference) based on a hydraulic pressure difference ΔPin between the hydraulic pressure of the high-pressure port 226 and the hydraulic pressure of the low-pressure port 227 (ΔPin = Pout1−Pin: hereinafter, referred to as the front-back hydraulic pressure difference) (Hereinafter, referred to as a differential pressure acting force) is not acting, the second magnetic path forming member 21 of the electromagnetic biased member 204 is not actuated.
The movement in the six directions stops when the urging force of the spring 206 and the electromagnetic driving force become equal.

As described above, the urging force of the spring 206, the differential pressure acting force, and the electromagnetic driving force act on the valve element 200 of the pressure-increasing linear valve 150, and the sum of the differential pressure acting force and the electromagnetic driving force is: When the force exceeds the biasing force of the spring, the valve 200
Are separated from the valve seat 202. Therefore, when the differential pressure acting force is small, a large electromagnetic driving force is required to separate the valve 200 from the valve seat 202, but when the differential pressure acting force is large, even if the electromagnetic driving force is small, It is possible to separate them. When the electromagnetic driving force is 0, the spring is separated if the differential pressure acting force becomes greater than the urging force of the spring. At this time, the hydraulic pressure difference before and after the pressure-increasing linear valve 150 is approximately 3 MPa in this embodiment. (About 30.
6 kgf / cm ² ).

Similarly, for the pressure reducing linear valve 152, the valve 200 has an urging force of the spring 220 and a hydraulic pressure difference ΔPout (ΔPou) before and after the pressure reducing linear valve.
t = Pout1−Pres), a differential pressure acting force and an electromagnetic driving force are applied, and while the sum of the differential pressure acting force and the electromagnetic driving force is larger than the urging force of the spring 224, the valve 200 is moved to the valve seat 202.
Separated from The valve opening pressure of the pressure-reducing linear valve 152 is set to be higher than 18 MPa (ｋｇ184 kgf / cm ² , the maximum hydraulic pressure of the working fluid supplied from the constant hydraulic pressure source 20). The urging force of the spring 224 is larger (about six times) than that of the spring 206. The maximum value of the hydraulic pressure of the working fluid acting on the valve 200 in the pressure reducing linear valve 152
And is the maximum hydraulic pressure stored in accumulator 14. Therefore, the hydraulic pressure due to the pedaling force of the operator exceeds this maximum hydraulic pressure, and the pressure reducing linear valve 15
It can be considered that the valve opening pressure of No. 2 is practically not exceeded.

On the other hand, a fluid pressure sensor 228 is
(See FIG. 1), and the hydraulic pressure of the master cylinder 12 with the booster is detected. The hydraulic pressure of the booster-equipped master cylinder 12 can be a hydraulic pressure corresponding to the required braking force intended by the driver. In the liquid passage 22,
When the stroke simulator 230 is connected and the electromagnetic valves 30 and 32 are both closed, the stroke of the brake pedal 19 is prevented from becoming almost zero.

The controller 66 includes the hydraulic sensors 62, 64, 88, 228 and the wheels 23, 25, 4,
Wheel speed sensors 110 for respectively detecting the wheel speeds 9 and 51
To 116, a brake switch 250 for detecting that the brake pedal 19 is depressed, a water temperature sensor 252 for detecting the temperature of engine cooling water (not shown), and the like. In addition to the solenoid of the valve, the solenoid of the linear valve device 56 and the like are connected via a drive circuit (not shown). Also, ROM
, A plurality of programs such as a regenerative braking cooperative control program, a table represented by a graph in FIG. 3, and the like are stored. FIG. 6 is a flowchart showing the contents of the viscosity-responsive hydraulic pressure control program which is a part of the regenerative braking coordination program.

When the brake pedal 19 is depressed, hydraulic pressures of substantially the same magnitude are generated in the two hydraulic chambers of the master cylinder 12 with the booster, and supplied to the wheel cylinders 24, 26 and the wheel cylinders 50, 52. Is done. When the regenerative braking cooperative control is performed while the hydraulic braking device is operating normally,
The electromagnetic on / off valves 30 and 32 are in the closed state, the electromagnetic on / off valve 80 is in the open state, and the other electromagnetic on / off valves are in the state shown in FIG. The supply of the hydraulic fluid to the wheel cylinders 24, 26 is performed not through the hydraulic passage of the master cylinder 12 with the booster but through the liquid passage 22, but through the liquid passage 48, and the wheel cylinders 50, 52 In the same manner as described above, the hydraulic fluid controlled by the linear valve device 56 is supplied. The hydraulic pressures of all the wheel cylinders are controlled by controlling the pressure increasing linear valve 150 and the pressure reducing linear valve 152 of the linear valve device 56. At the time of pressure reduction, the hydraulic fluid flows out of the wheel cylinder and is stored in the pressure reduction reservoir 154. When the regenerative braking cooperative control and the antilock control are performed in parallel, based on the hydraulic pressure controlled by the linear valve device 56, the electromagnetic on-off valves 58, 72, 84, 86,
When the wheels 42, 44 are switched between the open state and the closed state, the hydraulic pressure of the wheel cylinders is reduced.
The control is performed such that the braking slip states of 49 and 51 are maintained in an appropriate state.

In the regenerative braking cooperative control, the linear valve device 56 is controlled such that the output hydraulic pressure Pout1 detected by the hydraulic pressure sensor 64 approaches the target hydraulic pressure Pref. Pressure increasing linear valve 150, pressure reducing linear valve 152
Is applied to each of the solenoids 210. The target hydraulic pressure Pref is obtained by calculating a hydraulic pressure corresponding to the regenerative braking force from a hydraulic pressure corresponding to the hydraulic pressure Pmc of the master cylinder 12 with the booster, which is an output value of the hydraulic pressure sensor 228 (a hydraulic pressure corresponding to a driver's will). Obtained as the subtracted value.

In this embodiment, the voltage applied to the solenoid 210 of the pressure-increasing linear valve 150 (referred to as pressure-applied voltage Vapply) and the voltage applied to the solenoid 210 of the pressure-reducing linear valve 152 (pressure-reduced voltage Vre
lease)) according to the formula: Vapply = VFapply + VBapplyVrelease = VFrelease + VBrelease. The applied voltages VFapply and VFrelease determined in the feedforward control and the applied voltages VBapply determined in the feedback control
, VBrelease and the sum of
There is a restriction so that it does not exceed the set voltage. The set voltage is a voltage that can be kept open even if the pressure difference between the front and rear fluids is 0 in the pressure-increasing linear valve 150 and the pressure-reducing linear valve 152, and it is not necessary to apply a higher voltage. Feed forward boost voltage V
Fapply and feed forward decompression voltage VFreleas
e is the change amount of the target hydraulic pressure Pref and the hydraulic pressure difference ΔPi
n, ΔPout, the feedback boosted voltage VBapply and the feedback reduced voltage VBrele
ase is determined such that the hydraulic pressure deviation PB, which is a value obtained by subtracting the output hydraulic pressure Pout1 from the target hydraulic pressure Pref, approaches zero.

In the feedforward control, the above-mentioned feedforward boosted voltage VFapply and the feedforward reduced pressure voltage VFrelease are set to constant voltages Vca,
The magnitude is obtained by adding the change voltages Vga and Vgr to Vcr. VFapply = Vca + Vga VFrelease = Vcr + Vgr Here, the change voltages Vga and Vgr are expressed by the following equation: Vga = (Pref-Pref10) * Kff1 Vgr = (Pref20-Pref) * Kff2 Constant Kff
1, Kff2. Pref10, Pref2
0 is the target hydraulic pressure value when the pressure increase control is started and when the pressure decrease control is started, respectively.

The constant voltages Vca and Vcr are controlled by the pressure-increasing linear valve 1 when the pressure-increasing control or the pressure-decreasing control is started.
50, a magnitude corresponding to the minimum valve opening voltage of the pressure reducing linear valve 152, and is obtained based on FIGS. 3 (a) and 3 (b). As described above, in the pressure-increasing linear valve 150 and the pressure-decreasing linear valve 152, the sum of the electromagnetic driving force determined in accordance with the magnitude of the applied voltage and the differential pressure acting force determined in accordance with the front-rear hydraulic pressure difference is provided by a spring. Since the flow of the hydraulic fluid is allowed while the power is greater than the power, the minimum valve opening voltage required to open the seating valve 190 can be obtained based on the difference between the front and rear hydraulic pressures. If the electromagnetic driving force is small, the flow of the hydraulic fluid is not allowed even if the pressure increase control and the pressure decrease control are started, and a control delay occurs. In contrast, pressure increase control,
When the pressure reduction control is started, if a voltage equal to or more than the minimum valve opening voltage corresponding to the difference between the front and rear hydraulic pressures at the time of the start is applied, the flow of the hydraulic fluid is immediately allowed, and the control delay can be reduced.

FIG. 3A shows a pressure-increasing linear valve 150.
The relationship between the constant voltage Va and the front and rear hydraulic pressure difference ΔPout for the pressure reducing linear valve 152 is shown in FIG. 3B. Therefore, FIG. 3B showing the relationship of the pressure reducing linear valve 152 will be described first.
As shown in FIG. 3B, the constant voltage Vr is reduced substantially linearly with an increase in the hydraulic pressure difference ΔPout of the pressure reducing linear valve 152. As described above, the hydraulic pressure difference Δ
When Pout is large and the differential pressure acting force is large, the seating valve 190 can be opened even if the electromagnetic driving force is small. In addition, since the electromagnetic driving force increases substantially linearly with an increase in the applied voltage, the seating valve 19
The relationship between the electromagnetic driving force (applied voltage) and the difference between the front and rear hydraulic pressures for opening 0 is as shown in the figure. The front-rear hydraulic pressure difference ΔPout is the difference between the wheel cylinder-side hydraulic pressure of the pressure-reducing linear valve 152 and the pressure-reducing reservoir-side hydraulic pressure. However, the hydraulic pressure of the pressure-reducing reservoir 154 is substantially constant at atmospheric pressure. It is the same size as the side hydraulic pressure. As shown in FIG.
Also, in the same manner as in the pressure reducing linear valve 152, when the front-rear hydraulic pressure difference ΔPin is large, the seating valve 190 can be opened even if the applied voltage is small. However, the minimum valve opening voltage is not linearly decreased with an increase in the front-rear hydraulic pressure difference ΔPin, but is kept constant when the front-rear hydraulic pressure difference ΔPin is small and large. This is due to the relationship (operating characteristic) between the front-rear hydraulic pressure difference ΔPin and the minimum valve opening voltage for the pressure-intensifying linear valve 150.

As described above, if the constant voltages Va and Vr are obtained based on the front and rear hydraulic pressure differences ΔPin and ΔPout at the start of the pressure increase control and the start of the pressure decrease control, the feedforward pressure increase voltage VFapply and the feedforward pressure decrease voltage VF
The release is obtained according to the equation VFapply = (Pref-Pref10) * Kff1 + Vca VFrelease = (Pref20-Pref) * Kff2 + Vcr, as described above. As shown in FIG. 4, the target hydraulic pressure Pre
When f is changed, the feedforward boosted voltage VFapply and the feedforward reduced voltage VFrele
ase will be changed accordingly, as shown in the figure.

In the feedback control, the feedback boosted voltage VBapply and the feedback reduced voltage VBrelease are determined based on the PID control.
The feedback boosted voltage VBapply is calculated by the following equation: VBapply = KP1 * PB + KI1 * ΣPB + KD1 *
It is determined according to DPB / dt. Here, KP1, KI1, KD1
Are both constants. Similarly, the feedback reduced voltage V
Brelease is an equation using constants KP2, KI2, and KD2, VBrelease = KP2 * PB + KI2 * ΣPB + KD2
* It is determined according to DPB / dt.

As described above, the linear valve device 56
The output hydraulic pressure Pout1 is controlled so as to approach the target hydraulic pressure Pref. When the voltage is applied to the solenoid 210 of the pressure increasing linear valve 150, the pressure increasing control is performed, and the voltage is applied to the solenoid 210 of the pressure reducing linear valve 152. Is applied, pressure reduction control is performed. In the holding control, no voltage is applied to any of the solenoids. The selection of pressure increase, pressure decrease and holding in this case is performed based on the above-described hydraulic pressure deviation PB. As shown in FIG.
When the hydraulic pressure deviation PB is equal to or greater than the pressure-increase-side threshold DPLA, pressure increase is selected, and when it is equal to or less than the pressure-decrease-side threshold DPUR, pressure decrease is selected. Further, in this embodiment, since the control is provided with hysteresis, when the pressure is increased and the hydraulic pressure deviation PB becomes equal to or less than the pressure-increase-side threshold value DPLA, the control is switched to the holding instead of the holding. It is assumed that the value becomes equal to or less than the holding side threshold value DPLH which is smaller than the pressure increasing side threshold value DPLA. Similarly, the pressure reduction side threshold DPUR is obtained by reducing the pressure.
When the above is reached, the switching is not made to the holding, but is switched when the pressure becomes equal to or more than the holding threshold DPUH which is larger than the pressure reducing threshold DPUR. As described above, in the vehicle brake device, the hysteresis is provided for the control of the linear valve device 56, so that the control switching frequency of the pressure-increasing linear valve 150 and the pressure-reducing linear valve 152 is reduced, and control hunting is less likely to occur. Power consumption is reduced.

The range between the pressure-increasing-side threshold DPLA and the pressure-reducing-side threshold DPUR is smaller when the viscosity of the hydraulic fluid is high than when it is low. The range between them is reduced in order to reduce control delays due to high viscosity. If the range is reduced, pressure increase or pressure reduction may be selected even when holding is selected when viscosity is low, and control delay can be reduced accordingly. In the present embodiment, the pressure-increase-side threshold D
PLA is reduced, and the pressure reduction side threshold DPU
By increasing R, the range between them is reduced. This is because the control delay occurs both when the pressure increase control is performed and when the pressure decrease control is performed. The viscosity increases when the temperature of the hydraulic fluid is low, but the temperature of the hydraulic fluid is
The temperature is detected based on the temperature of the cooling water detected by the above-mentioned water temperature sensor 252 and the elapsed time since the ignition switch was turned on. The relationship between the temperature of the hydraulic fluid, the temperature of the cooling water of the engine, and the elapsed time is obtained, and a table (not shown) representing these relationships is stored in the ROM in advance, so that the operation is performed based on the temperature of the cooling water and the elapsed time. The temperature of the liquid can be detected, and the viscosity can be obtained. A viscosity acquisition device is constituted by the water temperature sensor 252, a timer for measuring the elapsed time, a portion of the ROM for storing the above table, and the like. In the present embodiment, when the temperature of the working fluid is equal to or lower than the set temperature, the viscosity is determined to be high.

The difference (hysteresis) KPH1 between the pressure increase threshold DPLA and the holding threshold DPHL and the difference (hysteresis) KPH2 between the pressure reduction threshold DPUR and the holding threshold DPHH are determined by the hydraulic fluid. It is changed according to the viscosity of If these differences are the same between a case where the viscosity is high and a case where the viscosity is low, the pressure increase control and the pressure reduction control may be excessively performed when the viscosity is high. In other words, when the range between the pressure increase threshold DPLA and the pressure decrease threshold DPUR is changed, it is desirable to change the hysteresis KPH1 and KPH2 accordingly. By reducing these differences as the range shrinks,
Excessive control can be avoided. In the present embodiment, when both of the hysteresis KPH1 and KPH2 are high in viscosity, the value is reduced, but the values of the holding-side thresholds DPLH and DPUH are maintained at the same value.

Further, the applied voltage is changed according to the viscosity of the working fluid. When the viscosity is high, the applied voltage is higher than when the viscosity is low. In the present embodiment, the coefficients KP1 and KI for determining the feedback boosted voltage VBapply and the feedback reduced voltage VBrelease described above.
1, KD1, KP2, KI2, and KD2 are made larger by making them larger. If the applied voltage is increased,
The flow rate of the working fluid allowed in the pressure-increasing linear valve 150 and the pressure-reducing linear valve 152 is increased, and the control delay caused by the high viscosity can be reduced.

As shown in the flowchart of FIG. 6, in step 1 (hereinafter abbreviated as S1; the same applies to the other steps), the temperature of the hydraulic fluid is obtained.
It is determined whether the temperature is equal to or lower than the set temperature. If the temperature is higher than the set temperature and the viscosity is determined to be low (normal viscosity),
The determination is YES, and in S2 and S3, the pressure-increase-side threshold DPLA, the pressure-decrease-side threshold DPUR, and the hysteresis KPH1 and KPH2 are set to the set values, and the coefficients are set to the set values. On the other hand, if it is determined that the viscosity is high, the determination is NO, and in steps S4 and S5, the pressure-increasing threshold DPLA and the pressure-decreasing threshold DPUR are determined.
And the hysteresis KPH1 and KPH2 are reduced,
The coefficient is increased.

As a result, as shown in FIG. 7, when the viscosity is high, the pressure-increasing-side threshold and the pressure-decreasing-side threshold are set to thresholds DPLA 'and DPUR', respectively, and the hysteresis is reduced. The hysteresis is KPH1 'and KPH2', respectively. The range between the pressure-increase-side threshold and the pressure-decrease-side threshold is reduced, and the hysteresis is accordingly reduced. If the viscosity is low, even if the holding control is performed, if the viscosity is high, the pressure increasing control or the pressure reducing control is performed, and the control delay can be reduced accordingly. Further, since the range between the pressure-increase threshold and the pressure-decrease threshold is changed according to the viscosity, it is possible to suppress a decrease in hydraulic control accuracy due to a difference in viscosity. Further, since the hysteresis has a magnitude corresponding to the range between the pressure-increase-side threshold and the pressure-decrease-side threshold, it is possible to avoid excessive control even when the range is reduced. . Further, the control delay is reduced by increasing the applied voltage when the viscosity is high as compared with when the viscosity is low. Further, according to the hydraulic pressure control device of the present embodiment, the range between the pressure increase side and the pressure decrease side threshold is merely changed in accordance with the viscosity, that is, the hydraulic pressure control is performed without greatly changing the conventional control. There is also an advantage that the influence of viscosity on control can be reduced, and a decrease in hydraulic control accuracy due to a difference in viscosity can be suppressed.

In this embodiment, the hydraulic pressure control valve device is constituted by the linear valve device 56 including the pressure increasing linear valve 150 and the pressure reducing linear valve 152, and the hydraulic pressure control means is constituted by the controller 66 and the like. Further, a threshold value changing means and a hysteresis changing means are constituted by a portion of the controller 66 which executes S4, and the like.
5 constitutes a viscous response supply power control means.

In the above embodiment, the viscosity is
Although obtained indirectly based on the temperature of the hydraulic fluid, two hydraulic pressure sensors 6 provided before and after the linear valve device 56 are provided.
The viscosity can also be directly obtained based on the difference between the hydraulic pressures detected by the pressure sensors 2 and 64 and the voltage applied to the solenoid 210 of the pressure-intensifying linear valve 150. Since the flow rate of the hydraulic fluid can be obtained based on the applied voltage,
Viscosity can also be determined based on Hagenhoajuille's law. In this case, if the viscosity is higher than the set viscosity, the range between the two thresholds will be changed. Further, according to the present embodiment, there is an advantage that the value of viscosity (viscosity) can be continuously obtained.

In the above embodiment, the selection of pressure increase, pressure decrease, and holding is determined based only on the hydraulic pressure deviation PB. However, it is determined in consideration of the amount of change in the target hydraulic pressure Pref. Is also good. Furthermore, the range between the pressure-increasing-side threshold DPLA and the pressure-reducing-side threshold DPUR has been changed in two stages, that is, when the viscosity is high and when the viscosity is low (normal), but is changed in three or more stages according to the viscosity. Or may be changed continuously according to the viscosity. For example, the size of the range can be determined according to the viscosity at that time. In the above embodiment, the magnitudes of the pressure-increase threshold and the pressure-decrease threshold are determined in advance depending on the case where the viscosity is low and the case where the viscosity is high, and are changed to the values. The range can also be determined according to the viscosity. When the range is changed, it is not necessary to change both the pressure-increase-side threshold DPLA and the pressure-decrease-side threshold DPUR, and only one of them may be changed.
Also in this case, the control delay can be reduced.

Further, in the above embodiment, the hysteresis is provided for the control of the linear valve device 56. However, it is not indispensable to provide the hysteresis, and when the hydraulic pressure deviation PB is equal to or more than the pressure increase side threshold value DPLA. Pressure boost,
Pressure reduction may be selected when the pressure is equal to or lower than the pressure reduction threshold DPUR, and holding may be selected when the pressure is between the pressure increase threshold DPLA and the pressure reduction threshold DPUR. Also in this case, if the range between the pressure-increase-side threshold DPLA and the pressure-decrease-side threshold DPUR is reduced, the control delay due to the high viscosity can be reduced. In addition, the hysteresis KPH1 and KPH2 are changed in accordance with the change in the range between the pressure increase threshold and the pressure decrease threshold. However, it is not essential to change the hysteresis, and the range is changed. If so, the control delay can be reduced. In addition, hysteresis KPH1, KP
Even if both of H2 are not changed, only one of them may be changed. In addition, hysteresis KPH1, KPH
With the change of PH2, the hold-side threshold values DPLH, DPU
H may be changed.

Further, it is not essential to change the applied voltage according to the viscosity. If the range between the pressure increasing side and the pressure decreasing side threshold is changed, the control delay can be reduced,
A decrease in hydraulic control accuracy can be suppressed. When changing the applied voltage, it is not essential to change the feedback boosted voltage VBapply and the reduced voltage VBrelease, but the feedforward boosted voltage VFapply and the reduced voltage VFre
Even if the lease is changed, the applied voltage Vapply and the applied voltage Vrelease, which are the sum of these, may be changed. Increase voltage applied voltage Vapply, reduced voltage applied voltage Vreleas
An appropriate amount depending on the viscosity may be added to e.

Also, the regenerative braking cooperative control is not limited to the mode in the above embodiment, but may be performed in another mode. It is not essential that both the feedback control and the feedforward control are performed, and only one of them may be performed. Further, the hydraulic braking device can be applied not only to a hybrid vehicle but also to an electric vehicle. Further, the present invention is not limited to the vehicle having the regenerative braking device, and may be applied to a vehicle having only a normal hydraulic braking device without the regenerative braking device. The present invention can be similarly implemented, except that the process of determining the hydraulic braking force by subtracting the regenerative braking force from the required braking force becomes unnecessary, and it is possible to reduce the control delay caused by the high viscosity of the working fluid. it can. Further, instead of the linear valve device 56, the present invention can be implemented by using a hydraulic pressure control valve device including an electromagnetic directional switching valve and an electromagnetic on-off valve. In addition, the present invention can be implemented in various modified and improved embodiments without departing from the scope of the claims.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a configuration of a hydraulic braking device including a hydraulic control device according to an embodiment of the present invention.

FIG. 2 is a system diagram schematically showing a configuration of a linear valve device included in the hydraulic pressure control device.

FIG. 3A is a table showing a relationship between a front-rear hydraulic pressure difference in a pressure-intensifying linear valve stored in a ROM of the hydraulic control device and a constant voltage applied to a solenoid. (B)
4 is a table showing a relationship between a front-rear hydraulic pressure difference in a pressure reducing linear valve stored in a ROM of the hydraulic control device and a constant voltage applied to a solenoid.

FIG. 4 is a diagram showing an example of a change in a feedforward voltage determined by the hydraulic control device.

FIG. 5 is a diagram showing an example of control of a linear valve device in the hydraulic pressure control device.

FIG. 6 is a flowchart showing a viscosity-responsive hydraulic pressure control program stored in a ROM of the hydraulic pressure control device.

FIG. 7 is a diagram illustrating an example of control of a linear valve device in the hydraulic pressure control device.

[Explanation of symbols]

 56 Linear valve device 66 Controller 150 Pressure increasing linear valve 152 Pressure reducing linear valve 252 Water temperature sensor

Continued on the front page (72) Inventor Akira Sakai 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (3)

[Claims] 1. A high pressure section, a low pressure section, and a wheel cylinder are provided between a high pressure section and a wheel cylinder to allow inflow of a hydraulic fluid from the high pressure section to a wheel cylinder. A hydraulic pressure control valve device, a wheel cylinder, when a hydraulic pressure deviation related amount relating to a hydraulic pressure deviation obtained by subtracting an actual wheel cylinder hydraulic pressure from a target hydraulic pressure of the wheel cylinder is equal to or more than a first threshold value, The hydraulic pressure of the wheel cylinder is reduced to a target hydraulic pressure by permitting the hydraulic fluid to flow into the wheel cylinder and permitting the hydraulic fluid to flow out of the wheel cylinder when the hydraulic fluid is equal to or less than a second threshold smaller than the first threshold. A hydraulic pressure control device including: a hydraulic pressure control device that adjusts a range between the first threshold value and the second threshold value according to a viscosity of the hydraulic fluid. Threshold to change Hydraulic control apparatus characterized by comprising further means. 2. The system according to claim 1, wherein said hydraulic pressure control means allows said inflow when said hydraulic pressure deviation related amount has reached said first threshold value, and sets said third pressure value to a third threshold value smaller than said first threshold value. An inflow control means for preventing the inflow when the flow reaches the second threshold; and a fourth threshold larger than the second threshold and allowing the outflow when the hydraulic pressure deviation related amount reaches the second threshold. An outflow control means for preventing the outflow when reaching a value, at least one of a difference between a first threshold value and a third threshold value, and a difference between a second threshold value and a fourth threshold value. 2. The hydraulic pressure control device according to claim 1, further comprising: a hysteresis changing unit that changes the hydraulic pressure according to the viscosity of the hydraulic fluid. 3. The hydraulic pressure control valve device according to claim 1, wherein a flow of the hydraulic fluid from the high pressure section to the wheel cylinder and a flow of the hydraulic fluid from the wheel cylinder to the low pressure section are changed according to the magnitude of the supplied power. Wherein the fluid pressure control means includes a viscosity corresponding supply power control means for determining the supply power according to the hydraulic pressure deviation related amount and the viscosity of the working fluid. 3. The hydraulic pressure control device according to 1 or 2.