JP2005262899A - Hydraulic control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the delay of a control filter value used for controlling braking cylinder hydraulic pressure relative to an actual change in the braking cylinder hydraulic pressure in a hydraulic control device with a filter. <P>SOLUTION: A correction coefficient is set at 1 when the change gradient of a filter value outputted from the filter is a set filter value gradient α0 and below, and is set at a value larger than 1 when the change gradient is larger than the set filter value gradient α0. Thus, the change gradient of the control filter value is set to be larger than the change gradient of the filter value when the change gradient of the filter value is larger than the set filter value gradient α0. According to the control filter value, the delay relative to the actual change in the braking cylinder hydraulic pressure is reduced in comparison with the filter value. Therefore, the accuracy of the hydraulic control can be improved by executing the control based on the control filter value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hydraulic control device that controls the hydraulic pressure of a hydraulic actuator based on a filter value from which a high-frequency component has been removed by a filter.

Patent Document 1 discloses a high-frequency filter (pump motor or the like) that processes a detection value by a master pressure detection device that detects a hydraulic pressure of a master cylinder in a hydraulic pressure control device that controls the hydraulic pressure of a brake cylinder based on a filter value. Equipped with a low-frequency filter (a filter that smoothes fluctuations in the hydraulic pressure caused by opening / closing of the solenoid valve), anti-lock operation state, solenoid valve opening / closing state, etc. It is described that either one of the two filters is selected based on the above.
JP-A-9-249106

  An object of the present invention is to reduce the delay of the filter value used for the control of the hydraulic actuator with respect to the actual hydraulic pressure change by changing the filter value when necessary.

Means and effects for solving the problem

The hydraulic pressure control device according to claim 1 includes: (a) a hydraulic pressure detecting device that detects the hydraulic pressure of the hydraulic pressure operating device; and (b) a filter that removes a high frequency component detected by the hydraulic pressure detecting device. A hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure operating device based on a filter value from which a high frequency component has been removed by the filter, and when the filter value needs to be changed, It is obtained by including a filter value changing unit to be changed.
The hydraulic pressure of the hydraulic actuator is controlled based on the filter value, but when the filter value needs to be changed, the filter value is changed and controlled based on the changed filter value. Hereinafter, a filter value from which high-frequency components have been removed by a filter, which is not changed when unnecessary, but is changed when necessary, and a value used for controlling the hydraulic actuator is referred to as a control filter value. Called. When the control filter value is used for feedback control, it can be called a feedback control filter value, and when it is used for feedforward control, it can be called a feedforward control filter value. The control filter value can also be referred to as a necessary change filter value. Furthermore, since the filter value is a value representing the hydraulic pressure, it can also be referred to as a changing hydraulic pressure value, an input hydraulic pressure value, or an acquired hydraulic pressure value when necessary.
As described above, in the hydraulic pressure control device described in this section, the delay with respect to the actual hydraulic pressure change is reduced by changing the filter value instead of switching the filter when necessary. As a result, when the hydraulic pressure of the hydraulic actuator is controlled based on the control filter value, the hydraulic pressure control accuracy can be improved.
Whether or not the filter value needs to be changed is detected by a change necessity detection device. For example, when the change delay of the filter value with respect to the actual hydraulic pressure change is large and it is estimated that the difference between the actual hydraulic pressure and the filter value is large, it is detected that the change necessity detection device needs to be changed. Can be.
The filter value changing unit can obtain the control filter value by substituting the filter value into a predetermined arithmetic expression. Then, at least a part of the coefficients included in the arithmetic expression can be a value determined according to the necessity of changing the filter value (for example, a value determined according to the change gradient of the filter value). Also, for example, the filter value may be changed by adding a correction amount (a positive value or a negative value), or the filter value may be a coefficient (for example, a value greater than 1). It can also be changed by multiplying.
The filter may be a digital filter or an analog filter. According to the filter, high frequency components can be removed from the output of the hydraulic pressure detection device. As a result, the detection value by the hydraulic pressure detection device is smoothed, but it cannot be avoided that the filter value changes after the change of the detection value. Note that the present invention can also be applied to a hydraulic control device including a plurality of different types of filters. Even in a hydraulic pressure control device in which one of a plurality of filters is selectively used, if the filter value after the filter processing is changed, the control filter value is changed to the actual hydraulic pressure device liquid. Can approach pressure.

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  Of the following items, the items (1) and (3) correspond to claims 1 and 2, the items (4) to (6) and (8) correspond to claims 3 to 6, Claims (13) and (14) correspond to claims 7 and 8, respectively.

(1) a hydraulic pressure detecting device for detecting the hydraulic pressure of the hydraulic pressure operating device;
A hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure operating device based on a filter value from which the high frequency component has been removed by the filter. ,
The hydraulic pressure control device includes a filter value changing unit that changes the filter value when the filter value needs to be changed.
(2) The hydraulic pressure control device according to (1), wherein the filter value changing unit includes means for changing the filter value when a change gradient of the filter value is larger than a set gradient.
The change gradient of the filter value with respect to time corresponds to an increase gradient or a decrease gradient of the filter value. When the change gradient of the filter value is large, it is considered that the delay with respect to the actual hydraulic pressure change is larger than when the filter value is small, so when the change gradient of the filter value is greater than or equal to the set gradient, Assuming that the filter value needs to be changed, it is desirable to make a change that brings the filter value closer to the actual hydraulic pressure.
The change of the filter value is performed in either of the cases where the increase gradient of the filter value is larger than the set gradient and the case where the decrease gradient is larger than the set gradient. It may not be performed in the other case.
(3) The hydraulic pressure control device according to (2), wherein the filter value changing unit includes a filter value gradient correspondence changing unit that changes the filter value based on a change gradient of the filter value.
For example, when the change gradient of the control filter value is made larger than the change gradient of the filter value, the ratio of the change gradient of the control filter value to the change gradient of the filter value (a value greater than 1, hereinafter simply referred to as the change gradient ratio). Can be made larger when the change gradient of the filter value is large than when it is small. This is because when the change gradient of the filter value is large, it is considered that the change delay with respect to the actual change in hydraulic pressure is larger than when the gradient is small.
(4) The hydraulic pressure difference in which the filter value changing unit changes the filter value when the absolute value of the difference between the filter value and the actual hydraulic pressure of the hydraulic pressure operating device is estimated to be greater than or equal to a set value. The fluid pressure control device according to any one of items (1) to (3), including a large estimation time change unit.
For example, as described above, when the change gradient of the filter value is greater than or equal to the set gradient, it is estimated that the absolute value of the difference between the filter value and the actual hydraulic pressure of the hydraulic actuator is greater than or equal to the set value. Can do.
Further, as will be described later, it is possible to estimate whether the absolute value of these differences is greater than or equal to a set value based on the operating state of the hydraulic pressure operating device, the hydraulic pressure control status by the hydraulic pressure control device, and the like. it can.
Furthermore, when the detection value by the hydraulic pressure detection device can be acquired (for example, when the output value of the sensor before the high-frequency component is removed by the filter can be acquired), the detection value and the filter value are Can actually be obtained. In this case, when the hydraulic pressure is being controlled by the hydraulic pressure control device, the temperature of the hydraulic fluid is low, and the hydraulic pressure detection device is provided apart from the hydraulic pressure operation device. The detected value by the device may differ from the actual fluid pressure. In this case, the actual fluid pressure of the fluid pressure operating device can be estimated based on the detected value by the fluid pressure detecting device.
Note that the hydraulic pressure difference large estimation time changing unit may change the filter value in accordance with the difference when it is estimated that the absolute value of the above difference is large. For example, when the absolute value of the difference is large, the change amount of the filter value is increased or the change gradient ratio is increased as compared with the case where the absolute value of the difference is small.
(5) The filter value changing unit includes an operation state corresponding change unit that changes the filter value based on at least one of an operating state of the hydraulic pressure operating device and a hydraulic pressure control state of the hydraulic pressure control device. The fluid pressure control device according to any one of (1) to (4).
Based on at least one of the operating state of the hydraulic actuator and the hydraulic control state of the hydraulic controller, whether or not the filter value needs to be changed, whether the filter value is changed, the change gradient ratio described above, the filter It is possible to determine at least one of whether the change of the filter value by the value changing unit is permitted or prohibited.
For example, when it is estimated that the change in the operating state of the hydraulic actuator (for example, it can be expressed by the amount of change in the hydraulic pressure of the hydraulic actuator, the change gradient, etc.) is large or small It can be considered that the change delay of the filter value with respect to the actual change in the hydraulic pressure is large, and the necessity of changing the filter value is high. In this case, the amount of change of the filter value and the change gradient ratio can be determined based on the amount of change in hydraulic pressure and the change gradient of the hydraulic actuator. Further, the change by the filter value changing unit can be permitted when the change in the operation state is large, and the change can be prohibited when the change in the operation state is small. Furthermore, the change by the filter value changing unit can be prohibited when the viscosity of the hydraulic fluid that defines the operating state of the hydraulic actuator is high, and can be permitted when the viscosity is normal.
Similarly, regarding the hydraulic pressure control state of the hydraulic pressure control device, it is considered that it is highly necessary to change the filter value when the change amount and change gradient of the hydraulic pressure control command value are large or when the change frequency is high. The filter value can be changed based on these change states.
For example, when the hydraulic pressure actuating device is a hydraulic brake that suppresses the rotation of the wheels of the vehicle, when the wheel slip control is performed by controlling the hydraulic pressure of the brake cylinder, the change gradient of the required braking force is large. If the filter value needs to be changed when high responsiveness is required (for example, when emergency assist control is performed), the filter value may be changed or the filter may need to be changed. Change the value.
(6) a hydraulic fluid temperature acquisition device for acquiring a hydraulic fluid temperature of the hydraulic pressure actuator;
When the temperature of the hydraulic fluid acquired by the hydraulic fluid temperature acquisition device is equal to or higher than a set temperature, the filter value changing unit allows the filter value to be changed, and when the temperature is lower than the set temperature, the filter value is changed. The hydraulic pressure control device according to any one of items (1) to (5), including a hydraulic fluid temperature corresponding change unit control unit that prevents the operation from being performed.
When the temperature of the hydraulic fluid is low and the viscosity is high, the actual hydraulic pressure change of the hydraulic pressure operating device is delayed in the same control state by the hydraulic pressure control device than when the temperature is normal and the viscosity is normal. Accordingly, when the viscosity of the hydraulic fluid is high, the necessity for changing the filter value is low, and the filter value is not changed by the filter value changing unit. In other words, it is desirable not to change the filter value. The set temperature is a temperature at which the viscosity is high and causes a problem. For example, the set temperature can be a value of about −30 ° C.
(7) a viscosity acquisition device that acquires the viscosity of the hydraulic fluid of the hydraulic operation device;
When the viscosity of the hydraulic fluid acquired by the viscosity acquisition device is high, the filter value changing unit allows the filter value to be changed, and when the viscosity is normal, the filter value is not changed. The fluid pressure control device according to any one of items (1) to (6), including a viscosity correspondence changing unit control unit.
Whether or not the viscosity of the hydraulic fluid is high can be acquired based on the temperature of the hydraulic fluid, but the viscosity of the hydraulic fluid can also be directly acquired.
For example, when one or more electromagnetic control valves are provided in the hydraulic pressure control device, the viscosity is acquired based on the hydraulic pressure difference before and after the electromagnetic control valve, the flow rate of hydraulic fluid passing through the electromagnetic control valve, and the like. Can do it.
(8) a hydraulic control actuator capable of controlling the hydraulic pressure of the hydraulic actuator;
An actuator controller for controlling the hydraulic control actuator;
A filter value change corresponding change unit control unit that permits or prohibits the change of the filter value by the filter value change unit based on the change state of the filter value after the operation of the hydraulic pressure control actuator stops. The fluid pressure control device according to any one of (1) to (7).
For example, when the viscosity of the hydraulic fluid is normal, the hydraulic pressure of the hydraulic actuator changes according to the operation of the hydraulic control actuator, and the filter value follows with a delay. On the other hand, when the viscosity of the hydraulic fluid is high, even after the operation of the hydraulic pressure control actuator is finished, the hydraulic pressure change corresponding to the operation appears in the hydraulic pressure actuator, and the filter is delayed after the hydraulic pressure change. The value changes. Further, when the hydraulic pressure detecting device for detecting the hydraulic pressure of the hydraulic pressure operating device is provided apart from the hydraulic pressure operating device, the hydraulic pressure of the hydraulic pressure operating device is changed with respect to the change of the hydraulic pressure of the hydraulic pressure detecting device. When the change is delayed and the steady state is reached after the operation of the hydraulic pressure control actuator is completed, the detection value by the hydraulic pressure detection device approaches the hydraulic pressure of the hydraulic pressure operation device, and the filter value also approaches the hydraulic pressure. Become.
Thus, based on the change state of the filter value after the operation of the hydraulic pressure control actuator is completed, it can be determined whether or not the viscosity of the hydraulic fluid is high. Based on the change state of the filter value after the operation is completed. It is reasonable to permit or prohibit the change of the filter value by the filter value changing unit. For example, when the viscosity of the hydraulic fluid is estimated to be high based on the change state of the filter value within a set time after the operation of the hydraulic control actuator is stopped, the change by the filter value changing unit is not performed. When the viscosity is estimated to be normal, the filter value can be changed.
In addition, it can be considered that the hydraulic pressure control apparatus includes a hydraulic fluid viscosity estimation unit that estimates the viscosity and temperature of the hydraulic fluid based on the change state of the filter value after the operation of the hydraulic pressure control actuator is stopped.
In addition, when the hydraulic pressure control actuator is controlled in a state where the hydraulic pressure of the hydraulic pressure actuator changes at a set gradient or more, the control by the filter value change corresponding change control unit described in this section is performed. can do. When the hydraulic pressure control actuator is operated so that the change gradient of the hydraulic pressure of the hydraulic actuator is equal to or greater than the set gradient, the normal or high viscosity is This is because the difference between this case and the case becomes significant.
(9) The hydraulic pressure control device can control the hydraulic pressure of the hydraulic pressure operating device, and the actuator that controls the hydraulic pressure control actuator based on the target hydraulic pressure of the hydraulic pressure operating device The filter value changing unit allows the filter value changing unit to change the filter value when the change gradient of the target hydraulic pressure is equal to or greater than a set gradient, and is smaller than the set gradient. The hydraulic pressure control apparatus according to any one of (1) to (8), including a target hydraulic pressure gradient correspondence changing unit control unit that prevents the filter value from being changed.
The hydraulic pressure of the hydraulic actuator is controlled by the hydraulic control actuator so that it is the same as the target hydraulic pressure. However, when the change gradient of the target hydraulic pressure is large, the hydraulic pressure change of the hydraulic actuator is large. It is estimated that there is a high possibility that the change delay of the filter value with respect to the actual change in the hydraulic pressure becomes large. For this reason, it is appropriate to change the filter value when the change gradient of the target hydraulic pressure is equal to or greater than the set gradient, and to prevent the filter value from being changed when the change gradient is smaller than the set gradient. That is.
Further, for example, the detection value by the hydraulic pressure detection device suddenly increases due to noise or the like, the filter value increases accordingly, and the filter value needs to be changed. The value may be changed with a larger gradient than the value variation gradient. On the other hand, if the change of the filter value is prohibited when the change gradient of the target hydraulic pressure is small, it is possible to prevent the control filter value from becoming excessive due to noise or the like.
(10) The hydraulic pressure control device includes: (a) a hydraulic pressure control actuator capable of controlling the hydraulic pressure of the hydraulic pressure operating device; and (b) the hydraulic pressure control actuator, the target hydraulic pressure of the hydraulic pressure operating device. The filter value changing unit changes the filter value according to the change gradient of the target hydraulic pressure when the change gradient of the target hydraulic pressure is greater than or equal to a set gradient. The hydraulic pressure control apparatus according to any one of (1) to (9), including a target gradient correspondence changing unit.
For example, when the change gradient of the target hydraulic pressure is equal to or greater than the set gradient, it is necessary to change the filter value, and the filter value can be changed based on the change gradient of the target hydraulic pressure. This is because, when the change gradient of the target hydraulic pressure is large, it is considered that there is a very high possibility that a delay in the change of the filter value occurs with respect to the actual change of the hydraulic pressure.
(11) The fluid pressure control device includes (a) a fluid pressure control actuator capable of controlling the fluid pressure of the fluid pressure operating device, and (b) the fluid pressure control actuator as a target fluid pressure of the fluid pressure operating device. A control command value creating unit that creates a control command value based on the control command value, and an actuator control unit that controls the hydraulic control actuator according to the control command value created by the control command value creating unit, the filter value The change unit includes a command value change corresponding change unit control unit that permits or prohibits the change by the filter value change unit based on the change gradient of the control command value. The fluid pressure control apparatus according to any one of the above.
The change gradient of the control command value often corresponds to the change gradient of the target hydraulic pressure, and if the change gradient of the control command value is large, the change gradient of the filter value is likely to be large. In addition, the filter value changing unit can be controlled based on the change gradient of the portion that changes in accordance with the change in the target hydraulic pressure in the control command value.
(12) The hydraulic pressure control device includes: (a) a hydraulic pressure control actuator capable of controlling the hydraulic pressure of the hydraulic pressure operating device; and (b) the hydraulic pressure control actuator, the target hydraulic pressure of the hydraulic pressure operating device. A control command value creating unit for creating a control command value based on the control command value, and an actuator control unit for controlling the hydraulic pressure control actuator according to the control command value created by the control command value creating unit, The value change unit includes a command value change corresponding change unit that changes the filter value according to the change gradient of the target hydraulic pressure when the change gradient of the control command value is equal to or greater than a set gradient. (11) The fluid pressure control device according to any one of items.

(13) The filter value changing unit includes a limited changing unit that changes the filter value so that an absolute value of a difference from the filter value does not exceed a set value. The fluid pressure control device according to claim 1.
When changing the filter value, it is not desirable that the difference between the filter value and the control filter value becomes excessive. Therefore, it is desirable that the filter value for control is determined by changing the filter value so that these differences do not exceed the set value.
For example, when the change coefficient is determined based on the change gradient of the filter value or the change gradient of the target hydraulic pressure, and the filter value is changed based on the change coefficient, an upper limit value is provided for the change coefficient. can do. In addition, the filter value changed based on the above-described change coefficient is compared with the filter value before the change, and the changed filter value is corrected so that the absolute value of these differences does not exceed the set value. The corrected value can be used as a control filter value.
(14) The hydraulic pressure actuating device is a hydraulic brake that suppresses rotation of a vehicle wheel by a hydraulic pressure of a brake cylinder, and the hydraulic pressure detecting device detects a hydraulic pressure of the brake cylinder. The fluid pressure control device according to any one of items (1) to (13), which is a detection device, and the fluid pressure control device is a brake fluid pressure control device that controls the fluid pressure of the brake cylinder.
In the hydraulic pressure control device described in this section, the output from the brake cylinder hydraulic pressure detection device is filtered, and the filter value of the filtered brake cylinder hydraulic pressure is changed by the filter value changing unit. In the hydraulic pressure of the brake cylinder, the control filter value is often used for feedback control.
Note that the present invention is not limited to the hydraulic pressure of the brake cylinder, and can be applied to the filter value when the hydraulic pressure of the master cylinder, the hydraulic pressure of the power type hydraulic pressure source, and the like are filtered.
(15) The hydraulic pressure operating device is a vehicle height adjusting device provided between a vehicle body side member and a wheel side member of a vehicle, and the hydraulic pressure detecting device is a liquid chamber included in the vehicle height adjusting device. The hydraulic pressure control device is a vehicle height adjustment control device that controls the hydraulic pressure of the vehicle height adjustment device. Any one of items (1) to (13) The hydraulic pressure control apparatus according to 1.

(16) a hydraulic pressure detecting device for detecting the hydraulic pressure of the hydraulic pressure operating device;
A hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure operating device based on a filter value from which the high frequency component has been removed by the filter. ,
A fluid pressure control device comprising: a filter value processing unit that processes the filter value based on at least one of an operation state of the fluid pressure detection device and a fluid pressure control state by the fluid pressure control device.
In the hydraulic pressure control device described in this section, the filter value is processed. Based on the operating state of the hydraulic pressure operating device and the hydraulic pressure control status by the hydraulic pressure control device, decide whether to permit or prohibit the change of the filter value, or change when the change of the filter value is allowed It is possible to determine whether or not it is necessary, and when it is necessary to change the filter value, it is possible to determine the mode of change (for example, the amount of change and the change gradient ratio).
The technical features described in any one of the items (1) to (15) can be employed in the hydraulic pressure control device described in this section.
(17) a hydraulic pressure detecting device for detecting the hydraulic pressure of the hydraulic pressure operating device;
A fluid pressure control device that controls the fluid pressure of the fluid pressure operating device based on the filter value processed by the filter, including a filter that processes a detection value by the fluid pressure detection device,
A hydraulic pressure control apparatus comprising: a filter value changing unit that changes the filter value when the filter value needs to be changed.
In the hydraulic pressure control device described in this section, the filter is a digital filter, and the detection value by the hydraulic pressure detection device is filtered.
The technical feature described in any one of the items (1) to (16) can be employed in the hydraulic pressure control device described in this item.
(18) a hydraulic pressure detecting device for detecting the hydraulic pressure of the hydraulic pressure operating device;
A hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure operating device based on a filter value from which the high frequency component has been removed by the filter. ,
When the hydraulic pressure control device needs to change the filter value, the filter value changing unit changes the filter value, and when there is a high possibility that the filter value needs to be changed, the filter value changing unit A hydraulic pressure control device comprising: a changing unit control unit that permits changing according to the above and prevents the filter value from being changed when the possibility is low.
When it is determined that the filter value needs to be changed in a state where the change by the filter value changing unit is permitted, the filter value is changed. In the state where the change by the filter value changing unit is prohibited, the filter value is not changed even if the filter value needs to be changed.
When the temperature of the hydraulic fluid is equal to or higher than the preset temperature, or when the change gradient of the target hydraulic pressure is equal to or higher than the preset gradient, there is a high possibility that the filter value needs to be changed. Changes are permitted. On the other hand, if the temperature of the working fluid is lower than the set temperature, if the change gradient of the target hydraulic pressure is smaller than the set gradient, it is considered that the filter value should not be changed, or the filter value needs to be changed. In these cases, the change by the filter value changing unit is prohibited.
The technical feature described in any one of the items (1) to (17) can be employed in the hydraulic pressure control device described in this item.
(19) a pressure detection device for detecting the pressure of the fluid pressure actuator;
A fluid pressure control device for controlling the pressure of the fluid pressure actuator based on a filter value from which the high frequency component has been removed by the filter, the filter removing a high frequency component detected by the pressure detection device,
The fluid pressure control device includes a filter value changing unit that changes a filter value when the filter value needs to be changed.
The technique for changing the filter value is not limited to the hydraulic pressure control device, and can be widely applied to the hydraulic pressure control device. The technical features described in the above items (1) to (18) can be applied to the fluid pressure control device.

Hereinafter, the case where the hydraulic pressure control apparatus which is one Example of this invention is applied to the brake hydraulic pressure control apparatus which controls the hydraulic pressure of the hydraulic brake which suppresses rotation of the wheel of a vehicle is demonstrated. The brake hydraulic pressure control device is included in the hydraulic brake device shown in FIG.
The hydraulic brake device shown in FIG. 1 includes a brake pedal 10 serving as a brake operation member, a master cylinder 12 including two pressurizing chambers, and a pump device serving as a power hydraulic pressure source operated by power. 14, including brakes 16 to 19 provided respectively corresponding to the wheels located on the front and rear sides. The brakes 16 and 17 are left and right front wheel brakes, and the brakes 18 and 19 are left and right rear wheel brakes. The brakes 16 to 19 are hydraulic brakes that are operated by the hydraulic pressure of the brake cylinders 20 to 23. The hydraulic brakes 16 to 19 are one mode of the hydraulic pressure operating device.
The master cylinder 12 includes two pressure pistons, and fluid pressure corresponding to the operation force is generated in the fluid pressure chambers in front of the two pressure pistons by operating the brake pedal 10 by the driver. Be made. The left and right front brake cylinders 20 and 21 are connected to the two pressurizing chambers of the master cylinder 12 via master passages 26 and 27, respectively. Master cutoff valves 29 and 30 are provided in the middle of the master passages 26 and 27, respectively. The master shut-off valves 29 and 30 are normally open electromagnetic on-off valves.
Further, four brake cylinders 20 to 23 are connected to the pump device 14 via a pump passage 36. The brake cylinders 20 to 23 are supplied with hydraulic pressure from the pump device 14 while being disconnected from the master cylinder 12, and the hydraulic brakes 16 to 19 are operated. The hydraulic pressure of the brake cylinders 20 to 23 is controlled by a hydraulic pressure control valve device 38.

The pump device 14 includes a pump 56 and a pump motor 58 that drives the pump 56. The suction side of the pump 56 is connected to the reservoir 62 via the suction passage 60, and the accumulator 70 is connected to the discharge side. The hydraulic fluid in the reservoir 62 is pumped up by the pump 56, supplied to the accumulator 70, and stored in a pressurized state. The reservoir 62 is a low-pressure container and stores the working fluid at almost atmospheric pressure.
Further, a portion on the downstream side (brake cylinder side) of the discharge side accumulator 70 of the pump 56 and a portion on the suction side of the pump 56 are connected by a relief passage 74. A relief valve 76 is provided in the relief passage 74. The relief valve 76 switches from the closed state to the open state when the hydraulic pressure on the accumulator side, which is the high pressure side, exceeds the set pressure.

The hydraulic pressure control valve device 38 (see FIG. 1) is connected to a pressure-increasing linear valve 100 to 103 provided in a pump passage 36 as a pressure-increasing passage, and a pressure-reducing passage 104 that connects the brake cylinders 20 to 23 and the reservoir 62. And pressure-reducing linear valves 110 to 113 provided. By controlling the pressure increasing linear valves 100 to 103 and the pressure reducing linear valves 110 to 113, the hydraulic pressures of the brake cylinders 20 to 23 can be individually controlled independently.
In this embodiment, the pressure increasing linear valves 100 to 103 and the pressure reducing linear valves 110 and 111 are normally closed electromagnetic control valves, and the pressure reducing linear valves 112 and 113 are normally open electromagnetic control valves.

As shown in FIG. 2, the normally closed linear valves 100 to 103, 110, and 111 include a valve element 120, a valve seat 122, a spring 124 that acts in a direction in which the valve element 120 is seated on the valve seat 122, and the like. 126 and a solenoid 132 having a coil 128, a drive member 130, and the like, and provided with a differential pressure acting force according to the differential pressure before and after the linear valve acting in a direction to separate the valve element 120 from the valve seat 122. It is done. In these linear valves 100 to 103, 110 and 111, the differential pressure acting force Fp according to the above-described differential pressure before and after, the electromagnetic driving force Fd by the solenoid 132, and the biasing force Fs of the spring 124 act in opposite directions. The relative positional relationship between the valve element 120 and the valve seat 122 is determined by the relationship between these forces.
Although the illustrations of the normally open linear valves 112 and 113 are omitted, they include a seating valve and a solenoid, and the urging force Fs of the spring and the differential pressure acting force Fp according to the differential pressure before and after the linear valve are seated. It is provided in a state of acting in the direction of opening the valve. On the other hand, the electromagnetic driving force Fd is applied in the direction for closing the seating valve. The relative positional relationship between the valve disc and the valve seat is determined by the relationship between these forces.

A stroke simulator device 180 is provided in the master passage 26. The stroke simulator device 180 includes a stroke simulator 182 and a normally closed simulator opening / closing valve 184, and the opening / closing of the simulator opening / closing valve 184 prevents the stroke simulator 182 from communicating with the master cylinder 12. Switched to the shut-off state.
In the present embodiment, the portion surrounded by the alternate long and short dash line in FIG. 1 is one unit, and is provided in a block as one holding member. This unit is referred to as a hydraulic control unit 190 (also referred to as a hydraulic control actuator) 190.

The hydraulic brake device is controlled based on a command from the brake ECU 200. The brake ECU 200 mainly includes a computer, and includes an execution unit 202, a storage unit 204, an input / output unit 206, and the like. The input / output unit 206 includes a filter 208 and the like.
The input / output unit 206 includes a brake switch 210, a stroke sensor 211, a master pressure sensor 214, a brake cylinder hydraulic pressure sensor 216, a wheel speed sensor 218, a hydraulic pressure source hydraulic pressure sensor 220, and a hydraulic fluid that acquires the temperature of the brake hydraulic fluid. A temperature acquisition device 222 or the like is connected. Further, the solenoids of the pressure-increasing linear valves 100 to 103, the pressure-decreasing linear valves 110 to 113, the master cutoff valves 29 and 30, and the simulator control valve 184 are connected via a driving circuit (not shown), and the electric motor 58 is driven (not shown). Connected through a circuit.

The filter 208 is a digital filter, and processes a detection value by the brake cylinder hydraulic pressure sensor 216 and outputs a filter value. A process for removing the high-frequency component of the detection value is performed, and the detection value is smoothed. Note that the detection value by the master pressure sensor 214, the detection value by the hydraulic pressure source hydraulic pressure sensor 220, and the like are also processed by the filter 208, but are not related to the present embodiment, so description of the processing of these detection values is omitted. To do.
The hydraulic fluid temperature acquisition device 222 acquires the temperature of the brake hydraulic fluid. For example, (a) include a hydraulic fluid temperature sensor that directly detects the temperature of the brake hydraulic fluid, or (b) include an engine cooling water temperature sensor that detects the temperature of the engine cooling water, based on the temperature of the engine cooling water. Including a friction material temperature sensor for detecting the temperature of the friction material of the hydraulic brakes 16 to 19, and estimating the temperature of the hydraulic fluid based on the temperature of the friction material. It can be made.
The storage unit stores a table selection program represented by the flowchart of FIG. 4, a control filter value determination program represented by the flowchart of FIG. 5, and the like, and a correction coefficient determination table represented by the map of FIG. Etc. are stored.

  During normal braking, the master cutoff valves 29 and 30 are closed, whereby the brake cylinders 20 to 23 are shut off from the master cylinder 12 and the brakes 16 to 19 are operated by the hydraulic pressure of the pump device 14. The hydraulic pressure of the brake cylinders 20 to 23 is controlled by the control of the hydraulic pressure control valve device 38. Based on the operation stroke detected by the stroke sensor 211, the master pressure detected by the master pressure sensor 214, etc., the driver's required braking force is obtained, and the target fluid of the brake cylinders 20-23 is obtained so as to obtain the required braking force. The pressure Pref is determined. The supply currents to the solenoids of the pressure-increasing linear valves 100 to 103 and the pressure-reducing linear valves 110 to 113 are determined so that the actual brake cylinder hydraulic pressure becomes the same as the target hydraulic pressure Pref.

Hereinafter, control of the brake cylinders 20 and 21 for the left and right front wheels will be described. In the present embodiment, as shown in FIG. 3, control that combines feedforward control and feedback control is performed on the pressure-increasing linear valves 100 and 101 and the pressure-decreasing linear valves 110 and 111.
The feedforward control unit 300 determines the feedforward supply currents IFSLA and IFSLR, and the feedback control unit 302 determines the feedback supply currents IBSLA and IBSLR. These sums are the pressure-increasing linear valves 100 and 101, and the pressure-reducing linear valves 110 and 111. Supply currents ISLA and ISLR.
ISLA = IFSLA + IBSLA
ISLR = IFSLR + IBSLR

In the feedforward control unit 300, the feedforward supply currents IFSLA and IFSLR are determined based on the target hydraulic pressure Pref and the like.
In the pressure-increasing linear valves 100 and 101 and the pressure-decreasing linear valves 110 and 111, as described above, the differential pressure acting force Fp and the electromagnetic driving force Fd and the urging force Fs of the spring 124 are applied in the opposite directions. When no current is supplied to the coil 128, the urging force Fs of the spring 124 is usually larger than the differential pressure acting force Fp, so that the valve element 120 is in a closed state in which it is seated on the valve seat 122. On the other hand, when a current is supplied to the coil 128, the coil 128 is opened / closed by the relationship between the sum of the differential pressure acting force Fp and the electromagnetic driving force Fd and the biasing force Fs of the spring 124.
As shown in FIG. 7, the electromagnetic driving force Fd required to switch the seating valve 126 from the closed state to the open state is larger than when the differential pressure acting force Fp is large and the differential pressure acting force Fp is large, as shown in FIG. Thus, the valve opening current (current corresponding to the valve opening voltage) increases. Similarly, in the control of the pressure-increasing linear valves 100 and 101 and the pressure-decreasing linear valves 110 and 111, when the brake cylinder hydraulic pressure approaches the target hydraulic pressure, the front-rear differential pressure is reduced and the differential pressure acting force Fp is reduced. As a result, the electromagnetic driving force Fd required to keep the seating valve 126 open increases, and the supply current increases.
In the present embodiment, as shown in FIG. 8, for the pressure increasing linear valves 100 and 101, the valve opening current IFopen is determined based on the differential pressure before and after the start of the pressure increasing control, and the target hydraulic pressure Pref The target hydraulic pressure change-corresponding current IFref is determined in accordance with the change of, and the sum of these is set as the feed forward current IFSLA (IFopen + IFref). The same applies to the pressure reducing linear valves 110 and 111. The valve opening current IFopen is determined based on the differential pressure before and after the start of the pressure reducing control, and the target fluid pressure change corresponding current IFref is determined according to the change in the target fluid pressure. The sum of these values is taken as the feed forward current IFSLR (IFopen + IFref).

In the feedback control unit 302, feedback supply currents IBSLA and IBSLR are determined based on the target hydraulic pressure Pref and a value (hereinafter referred to as a control filter value) PwEST processed by the processing unit 304. The supply current is determined based on a deviation error between the control filter value PwEST and the target hydraulic pressure Pref. When the deviation error is large, the feedback currents IBSLA and IBSLR are made larger than when the deviation error is small.
The sum of the feedforward supply current and the feedback supply current obtained in this way is supplied to the coils 128 of the pressure-increasing linear valves 100 and 101 and the pressure-reducing linear valves 110 and 111, respectively.

In the present embodiment, the detection value by the brake cylinder hydraulic pressure sensor 216 is processed by the filter 208, and the filter value Pw that is the output value of the filter 208 is processed by the processing unit 304 to determine the control filter value PwEST. The
As shown in FIG. 11, when the change gradient of the detected value by the brake cylinder hydraulic pressure sensor 216 is large, the change delay of the filter value Pw is larger than when the gradient is small. The change gradient of the filter value Pw becomes smaller than the change gradient of the detected value by the brake cylinder hydraulic pressure sensor 216. When the change gradient is large, the difference between them is larger than when the change gradient is small. Therefore, in this embodiment, when the change gradient of the filter value Pw is equal to or greater than the set filter value gradient, which is a problem gradient, it is determined that “the filter value Pw needs to be changed”. .

  The change of the filter value Pw is permitted when it is estimated that the change delay of the filter value Pw is likely to be large, and it is desirable that the filter value Pw is not changed when it is estimated that the possibility is low. In some cases it is prohibited. For example, when the temperature of the hydraulic fluid is lower than a set temperature (for example, −30 ° C. or less) where viscosity is a problem, or when the change gradient of the target hydraulic pressure Pref is smaller than the set target hydraulic pressure gradient, the filter value is changed. Although not performed, when the viscosity of the hydraulic fluid is in a normal state, or when the change gradient of the target hydraulic pressure Pref is equal to or higher than the set target hydraulic pressure gradient, the change of the filter value is permitted. The change gradient of the target hydraulic pressure Pref is the change gradient of the target hydraulic pressure change corresponding current IFref included in the feedforward control current among the supply currents to the pressure-increasing linear valves 100 and 101 and the pressure-decreasing linear valves 110 and 111 described above. It can also be acquired based on. The change of the filter value can be permitted when the change gradient of the target hydraulic pressure change corresponding current IFref is equal to or greater than the set current gradient. In any case, the set target hydraulic pressure gradient and the set current gradient are determined to have a magnitude that may cause a delay in the change of the filter value.

The filter value Pw is calculated by the processing unit 304 using the expression PwEST (n) = PwEST (n−1) + (dPw / dt) · ΔT · K (1)
Will be processed according to. Here, PwEST is a control filter value, and Pw is a filter value. ΔT is the execution interval of the control filter value determination program, K is a correction coefficient (change coefficient), and as shown in FIGS. 6A and 6B, correction coefficient determination table X or correction coefficient determination The value is determined according to one of the tables Y.

Regarding the correction coefficient determination table X, the correction coefficient is set to 1 when the gradient of the filter value Pw is equal to or less than the set filter value gradient α0, but when the gradient is greater than the set filter value gradient α0 and equal to or less than α1, the filter value Pw It increases as the gradient increases and remains constant when it is greater than the gradient α1.
Thus, when the change gradient of the filter value Pw is larger than the set filter value gradient α0 and the filter value Pw needs to be changed, the correction coefficient is set to a value larger than 1. Accordingly, in equation (1), if the correction coefficient K is greater than 1, the change gradient of the control filter value PwEST is made larger than the change gradient of the filter value Pw, and the change gradient of the control filter value PwEST is The ratio of the filter value Pw to the change gradient is determined by the correction coefficient K. As a result, it is possible to suppress a change delay of the control filter value PwEST with respect to a change in the actual brake cylinder hydraulic pressure.
Further, the correction coefficient K is provided with an upper limit value, and is limited when it increases as the change gradient of the filter value Pw increases. In this embodiment, the correction coefficient K is kept constant when the gradient of the filter value is larger than the gradient α1, and as a result, the control filter value PwEST is prevented from becoming excessive with respect to the filter value Pw. The

  Regarding the correction coefficient determination table Y, the correction coefficient K is set to 1 regardless of the change gradient of the filter value Pw. When the correction coefficient K is 1, the ratio of the change gradient of the control filter value PwEST to the change gradient of the filter value Pw is 1, and the change gradient of the filter value Pw is not changed.

In the present embodiment, one of the tables X and Y is selected based on the temperature of the hydraulic fluid, the change gradient of the target hydraulic pressure Pref, and the like as described above.
When the correction coefficient determination table X is selected, the filter value Pw is changed when the change gradient of the filter value Pw is equal to or greater than the set filter value gradient and needs to be changed. In other words, the change of the filter value Pw is permitted, and “the correction coefficient determination table X is selected” means that “the change of the filter value Pw by the filter changing unit 306 is permitted”. Corresponding to
When the table Y is selected, the filter value is not substantially changed as described above. Even if the change gradient of the filter value Pw is larger than the set filter value gradient, the change gradient of the filter value Pw and the change gradient of the control filter value PwEST are the same. Therefore, “map Y has been selected” means “change in filter value by the filter changing unit 306 is prohibited” or “preventing change of the filter value by the filter changing unit 306”. Correspond.

The table selection program represented by the flowchart of FIG. 4 is executed at predetermined time intervals.
In step 1 (hereinafter abbreviated as S1. The same applies to other steps), it is determined whether or not the temperature of the hydraulic fluid is equal to or lower than a set temperature. In S2, the change gradient of the target hydraulic pressure Pref is set as a set target. It is determined whether or not it is equal to or higher than the hydraulic pressure gradient. In S3, it is determined whether or not the change gradient of the target hydraulic pressure change corresponding current IFref is equal to or higher than the set current gradient.
When the temperature of the working fluid is higher than the set temperature and the change gradient of the target hydraulic pressure Pref is equal to or higher than the set target hydraulic pressure gradient or the change gradient of the target hydraulic pressure change corresponding current IFref is equal to or higher than the set current gradient , S4, the correction coefficient determination table X is selected. On the other hand, when the temperature of the working fluid is lower than the set temperature, or when the temperature of the working fluid is higher than the set temperature but the change gradient of the target fluid pressure Pref is smaller than the set target fluid pressure gradient, When the change gradient of the pressure change corresponding current IFref is smaller than the set current gradient, the table Y is selected in S5.

The control filter value determination program represented by the flowchart of FIG. 5 is executed at predetermined time intervals. This program is executed at a cycle shorter than the execution cycle of the table selection program described above.
In S21, the correction coefficient K is determined based on the change gradient of the filter value Pw according to the selected table. In S22, the correction coefficient K, the change gradient of the filter value Pw, and the previous control filter value PwEST (n-1). And the like are substituted into the expression (1) to obtain the current value PwEST (n) of the control filter value by calculation. In S23, it is determined whether or not the absolute value of the difference between the control filter value PwEST (n) and the filter value Pw is greater than or equal to a set value. If the absolute value of the difference is greater than or equal to the set value, the control filter value PwEST (n) is brought close to the filter value Pw in S24. The control filter value PwEST (n) is corrected, and the corrected control filter value (PwEST (n) ± β) is output. On the other hand, if the absolute value of the difference is smaller than the set value, the control filter value PwEST is output in S25.

As described above, in this embodiment, the filter value is changed when it is necessary to change the delay of the change in the filter value Pw with respect to the actual change in the brake cylinder hydraulic pressure. As a result, even when the change gradient of the brake cylinder hydraulic pressure is large, it is possible to reduce the change delay of the control filter value PwEST and bring it closer to the actual brake cylinder hydraulic pressure. Therefore, the control accuracy of the brake cylinder hydraulic pressure can be improved.
Further, when the temperature of the hydraulic fluid is lower than the set temperature and the viscosity is high, the filter value Pw is not changed. Therefore, by changing the filter value Pw, it is possible to avoid the difference between the control filter value PwEST and the actual brake cylinder hydraulic pressure from increasing.
Further, the filter value Pw is not changed even when the change gradient of the target hydraulic pressure Pref is small. For example, even if the brake cylinder hydraulic pressure changes suddenly due to disturbance or the like and the change gradient of the filter value Pw increases, the filter value is changed due to this, and the control filter value PwEST becomes the actual brake value. It is possible to avoid a value greatly separated from the cylinder hydraulic pressure.
Further, since an upper limit is added to the correction coefficient K, it is possible to avoid an increase in the absolute value of the difference between the control filter value PwEST and the filter value Pw. The same effect can be obtained by executing S23 and S24 of the control filter value determination program. If both of these are adopted, it is possible to avoid the absolute value of these differences from being excessively more sure.

  Thus, in the present embodiment, the filter changing unit 306 corresponds to a filter value gradient correspondence changing unit and a hydraulic pressure difference large estimation changing unit. The filter changing unit 306 also corresponds to a response changing unit such as an operating state. Furthermore, the hydraulic fluid temperature corresponding change part control unit is configured by the part that stores S1, 4, and 5 in the table selection program of the brake ECU 200, the part that executes the program, and the like. Further, the correction coefficient determination table X is created so that the correction coefficient K is set to a constant value when the gradient of change in the filter value is greater than the gradient α1, and S23 of the control filter value determination program for the brake ECU 200. , 24 is stored, and at least one of the parts to be executed, etc. constitutes a limited change unit. Further, in the correction coefficient determination table X, when the change gradient of the filter value Pw is equal to or greater than the set filter value gradient, the correction coefficient K is set to a value greater than 1, and the filter value is determined in S21 of the control filter value determination program. It can be considered that the change necessity detection device is configured by determining the correction coefficient K based on the change gradient.

In the above-described embodiment, both S2 and S3 are executed in the table selection program, but either one may be executed. This is because when the change gradient of the target hydraulic pressure Pref is greater than or equal to the set target hydraulic pressure gradient, the change gradient of the target hydraulic pressure change-corresponding current IFref is often greater than or equal to the set current gradient.
Further, when the temperature of the hydraulic fluid is equal to or higher than the set temperature, whether or not the change gradient of the target hydraulic pressure Pref is equal to or lower than the set target hydraulic pressure gradient, the change gradient of the target hydraulic pressure change corresponding supply current IFref is set current. It is also possible to select the correction coefficient determination table X without determining whether or not it is equal to or less than the gradient.
Further, in the above-described embodiment, when the change gradient of the filter value Pw is equal to or greater than the set filter value gradient, it is necessary to change the filter value Pw. However, the change gradient of the target hydraulic pressure Pref is the set target value. It may be necessary to change when the pressure gradient is higher than the hydraulic pressure gradient. This is because when the change gradient of the target hydraulic pressure Pref is greater than or equal to the set target hydraulic pressure gradient, the possibility that the change gradient of the filter value Pw is also greater than or equal to the set filter value gradient is very high. In this case, the correction coefficient K can be determined according to the change gradient of the target hydraulic pressure Pw.
Further, the steps S23 and S24 of the control filter value determination program are not essential.

Furthermore, the temperature or viscosity of the hydraulic fluid can be estimated based on the change state of the filter value Pw after the operation of the pressure-increasing linear valve is stopped. This estimation is effective when the pressure-increasing linear valve is controlled in a state where the target increase gradient of the brake cylinder hydraulic pressure is equal to or greater than the set pressure increase gradient.
For example, when current is supplied to the pressure-increasing linear valves 100 and 101 as shown in FIG. 9 (a), when the viscosity of the hydraulic fluid is normal, the filter is shown as a solid line in FIG. 9 (b). When the value Pw changes and the viscosity is high, it changes as shown by the solid line in FIG.
When the viscosity is normal, the value detected by the brake cylinder hydraulic pressure sensor 216 (described as a sensor output value in the figure) is estimated to change as indicated by the broken line, but the detected value is the actual brake cylinder hydraulic pressure. The filter value Pw changes after a change in the detection value by the brake cylinder hydraulic pressure sensor 216 and then approaches the detection value. Accordingly, after the supply of current to the pressure-increasing linear valves 100 and 101 is stopped, when the filter value Pw is kept constant after increasing, it can be estimated that the viscosity is normal. In this case, while the current is supplied to the pressure-increasing linear valves 100, 101, that is, the change gradient of the filter value Pw during the pressure-increasing control is acquired, and after the pressure-increasing control is completed, the change gradient of the filter value Pw is It is also possible to acquire that the viscosity is normal in consideration of the fact that it has become gentle.

When the viscosity is high, the value detected by the brake cylinder hydraulic pressure sensor 216 and the actual brake cylinder hydraulic pressure are not always the same as indicated by the broken line and the alternate long and short dash line in FIG. As shown in FIG. 1, the brake cylinder hydraulic pressure sensor 216 is provided in the hydraulic pressure control unit 190, whereas the brake cylinders 20 to 23 are connected to the unit 190. The change in the detection value by the brake cylinder hydraulic pressure sensor 216 is delayed. On the other hand, in the steady state after the operation of the pressure increasing linear valves 100 and 101 is stopped, the detected value of the sensor and the actual brake cylinder hydraulic pressure are the same, and the filter value Pw is delayed with respect to the change of the detected value. Changes as indicated by the solid line. Therefore, when the filter value Pw increases and then decreases after the supply of current to the pressure-increasing linear valves 100 and 101 is completed, it can be estimated that the viscosity of the hydraulic fluid is high.
Thus, since the change state of the filter value Pw after the supply of current to the pressure-increasing linear valves 100 and 101 is stopped (after the pressure-increasing control is finished) is different depending on whether the viscosity is normal or high. Based on the change state, it is possible to acquire whether the viscosity of the hydraulic fluid is high.

Then, when the viscosity is high, the change of the filter value Pw by the filter value changing unit 306 is prohibited, and when the viscosity is normal, the change by the filter value changing unit 306 can be permitted.
The table selection program represented by the flowchart of FIG. 10 is executed at predetermined time intervals.
In S50, it is determined whether or not the supply current ISLA to the pressure-increasing linear valves 100 and 101 is larger than zero. It is determined whether the pressure increase control is being performed. If the pressure increase control is being performed, it is determined in S51 whether or not the change gradient of the target hydraulic pressure change corresponding current IFref is greater than or equal to the set pressure increase gradient. Is reset, and if it is equal to or greater than the set pressure increase gradient, a flag is set in S53. It is determined whether or not the pressure increase control in which the target increase gradient of the hydraulic pressure of the brake cylinder is equal to or greater than the set pressure increase gradient is performed.
When the pressure increase control is completed, it is determined in S54 whether or not a flag is set (whether or not the flag is in an ON state). When the flag is not set, S55 and subsequent steps are not executed. If the flag is set, it is determined in S55 whether or not S55 is executed first. When it is executed first, a timer is started in S56, and the filter value Pw is stored in S57. If it is the second time or later, it is determined in S58 whether the set time has elapsed. Before the set time elapses, the filter value Pw is stored in S57.
If the set time has elapsed, the determination in S58 is YES, and in S59, the change state is acquired based on the stored filter value Pw. In S60, the viscosity is estimated based on the change value, and S61. The correction coefficient determination table is selected based on the estimated viscosity.

As described above, in this embodiment, the viscosity is acquired based on the change state of the filter value Pw after the pressure increase control is completed, so that there is an advantage that a temperature sensor or the like for detecting the temperature of the hydraulic fluid is unnecessary. .
Note that the table selection program represented by the flowchart of FIG. 10 can also be used as a viscosity estimation program. In this case, step S61 is not necessary. The estimated result of the viscosity of the hydraulic fluid can be used in S1 of the table selection program represented by the flowchart of FIG.
In the present embodiment, a filter value change correspondence changing unit control unit is configured by a part that stores the table selection program represented by the flowchart of FIG. 10 of the brake ECU 200, a part that executes the program, and the like. The hydraulic control actuator is configured by the above.

Further, the control filter value PwEST is expressed by the equation PwEST (n) = PwEST (n−1) + (dPw / dt) · ΔT · K− {PwEST (n−1) −Pw} · Ka (2)
As required. Here, the coefficient Ka is a value larger than 0 and smaller than 1, and may be 0.9, for example. Based on Expression (2), the current control filter value PwEST is determined based on the difference {PwEST (n-1) -Pw} between the previous control filter value and the filter value. Thus, even if the difference between the control filter value PwEST and the filter value Pw increases, the control filter value PwEST can be quickly brought close to the filter value Pw.
When the coefficient Ka is large, the control filter value PwEST can be brought closer to the filter value Pw more quickly than when the coefficient Ka is small. In this sense, the coefficient Ka can be referred to as a convergence coefficient.
Further, according to the present embodiment, even if the difference between the control filter value PwEST and the filter value Pw is increased due to noise or the like, it can be brought close to the filter value Pw, so that the change gradient of the target hydraulic pressure Pref It is not indispensable to permit or prohibit the change by the filter changing unit 304 based on the above.

Furthermore, the viscosity of the hydraulic fluid is determined based on the differential pressure before and after at least one of the pressure-increasing linear valves 100 and 101 and the pressure-reducing linear valves 110 and 111 and the flow rate of the flowing hydraulic fluid. It can also be obtained according to the law.
Further, the control of the hydraulic control valve device 38 in the above embodiment is one aspect, and it is not indispensable that both feedback control and feedforward control are performed. For example, even when only feedback control is performed, the same effect can be obtained by changing the filter value Pw of the brake cylinder hydraulic pressure.
Further, in the above-described embodiment, the case where the control is applied to the hydraulic pressure control of the brake cylinders 20 and 21 of the front wheels has been described. Alternatively, the present invention may be applied to control of the pressure-reducing linear valves 110 and 111 that are normally closed electromagnetic control valves. Further, even when applied to the control of the pressure-increasing linear valves 102 and 103 which are normally closed electromagnetic control valves for the rear wheels, it is applied to the control of the pressure reducing linear valves 112 and 113 which are normally open electromagnetic control valves for the rear wheels. May be.

Furthermore, the present invention can be applied to a hydraulic pressure control device including a plurality of types of filters such as a high frequency removing filter and a low frequency removing filter. Even in this case, the change delay of the filter value can be made smaller by changing the filter value than when the filter is changed.
Further, the present invention is not limited to a hydraulic pressure control device for a hydraulic brake device for a vehicle, but is applied to a hydraulic pressure control device that controls the hydraulic pressure of a hydraulic pressure operating device such as a vehicle height adjusting device mounted on the vehicle. In addition to the aspects described above, the present invention can be implemented in various modifications and improvements based on the knowledge of those skilled in the art.

It is a circuit diagram of a hydraulic brake device provided with a hydraulic control device which is one example of the present invention. It is sectional drawing of the electromagnetic control valve contained in the said hydraulic control apparatus. It is a control block diagram of the hydraulic pressure control device. It is a flowchart showing the table selection program memorize | stored in the memory | storage part of the said hydraulic-pressure control apparatus. It is a flowchart showing the filter value determination program for control memorize | stored in the memory | storage part of the said hydraulic-pressure control apparatus. It is a map which shows notionally the correction coefficient determination table memorize | stored in the memory | storage part of the said hydraulic-pressure control apparatus. It is a map which represents notionally the valve opening current determination table memorize | stored in the memory | storage part of the said hydraulic pressure control apparatus. It is a figure which shows the change state of the supply current to the said electromagnetic control valve. It is a figure which shows the relationship etc. of the supply state of the electric current to the electromagnetic control valve of the said hydraulic-pressure control apparatus, and the change state of a filter value. It is a flowchart showing another table selection program memorize | stored in the memory | storage part of the said hydraulic-pressure control apparatus. It is a figure which shows the relationship between the detection value by a hydraulic pressure sensor, and a filter value in a hydraulic control apparatus.

Explanation of symbols

208: Filter 216; Brake cylinder hydraulic pressure sensor 306: Processing section

Claims (8)

A fluid pressure detecting device for detecting the fluid pressure of the fluid pressure operating device;
A hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure operating device based on a filter value from which the high frequency component has been removed by the filter. ,
A hydraulic pressure control apparatus comprising a filter value changing unit that changes a filter value when the filter value needs to be changed.   2. The hydraulic pressure control according to claim 1, wherein the filter value changing unit includes a filter value gradient corresponding changing unit that changes the filter value based on a change gradient when the change gradient of the filter value is larger than a set gradient. apparatus.   When the filter value changing unit is configured to estimate the hydraulic pressure difference when the absolute value of the difference between the filter value and the actual hydraulic pressure of the hydraulic pressure operating device is estimated to be greater than or equal to a set value. The hydraulic control device according to claim 1, comprising a changing unit.   The filter value changing unit includes an operation state correspondence changing unit for changing the filter value based on at least one of an operation state of the hydraulic pressure operating device and a hydraulic pressure control state of the hydraulic pressure control device. The hydraulic control device according to any one of 1 to 3. A hydraulic fluid temperature acquisition device for acquiring a hydraulic fluid temperature of the hydraulic pressure actuator;
When the temperature of the hydraulic fluid acquired by the hydraulic fluid temperature acquisition device is equal to or higher than a set temperature, the filter value changing unit allows the filter value to be changed, and when the temperature is lower than the set temperature, the filter value is changed. The hydraulic pressure control device according to any one of claims 1 to 4, further comprising a hydraulic fluid temperature corresponding change unit control unit that prevents the operation from being performed. A hydraulic control actuator capable of controlling the hydraulic pressure of the hydraulic actuator;
An actuator controller for controlling the hydraulic control actuator;
A filter value change corresponding change unit control unit that permits or prohibits the change of the filter value by the filter value change unit based on the change state of the filter value after the operation of the hydraulic pressure control actuator stops. The fluid pressure control device according to any one of claims 1 to 5.   The liquid according to any one of claims 1 to 6, wherein the filter value changing unit includes a restricted changing unit that changes the filter value so that an absolute value of a difference from the filter value does not exceed a set value. Pressure control device.   The hydraulic actuator is a hydraulic brake that suppresses rotation of a vehicle wheel by the hydraulic pressure of a brake cylinder, and the hydraulic pressure detector is a brake cylinder hydraulic pressure detector that detects the hydraulic pressure of the brake cylinder. 8. The hydraulic pressure control device according to claim 1, wherein the hydraulic pressure control device is a brake hydraulic pressure control device that controls the hydraulic pressure of the brake cylinder.

Images