JP2000025593A - Brake control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set the control gain of a linear valve device to be appropriate in both regular and non-regular controls. SOLUTION: When a brake pedal is operated by a driver in a regular condition, the regular braking control is effected. The control gain is set to be the gain KC for the regular control, and the applied voltage of a linear valve device is determined (S30, 40) so that the difference between the target hydraulic pressure and the actual hydraulic pressure is reduced. When the braking slip condition is excessive, the anti-lock control is effected, and the gain in this condition is set to the gain KA for the anti-lock control (S50). Since the gain KA for the anti-lock control is larger than the gain KC for the regular control, the responsiveness during the anti-lock control can be improved while preventing the hunting in the regular braking control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art An example of a brake control device including an actuator for operating a brake and an actuator control device for controlling a braking force by controlling the actuator is disclosed in Japanese Patent Laid-Open No. 4-278.
872. In the brake control device described in this publication, a control gain for controlling the actuator is determined according to the vehicle speed. When the vehicle speed is high, the control gain is made larger than when the vehicle speed is low. As a result, the responsiveness of the brake when the vehicle speed is high can be improved. However, in the brake control device described in the above publication, as long as the vehicle speed is the same, the control gain has the same magnitude in both the normal control and the non-normal control. Therefore, if the control gain is set to a value suitable for normal control, a problem such as a response delay occurs during non-normal control, and if the control gain is set to a value suitable for non-normal control, hunting occurs during normal control. There was a problem.

[0003]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a brake capable of performing good brake control in both normal control and non-normal control. It is to get the control device.
According to the present invention, the following brake control devices can be obtained. As in the case of the claims, each aspect is divided into sections, each section is numbered, and if necessary, the other sections are cited in a form in which the numbers are cited. This is for the purpose of facilitating the understanding of the possibility of the combination of the features described in each section, and it is to be understood that the technical features and the combinations thereof described in this specification are limited to the following. Should not be. (1) In a brake control device including an actuator that operates a brake and an actuator control device that controls a braking force by controlling the actuator, a control gain when controlling the actuator is controlled by the actuator control device. A brake control device including control gain determining means for increasing control gain during non-normal control compared to normal control (claim 1). In the brake control device described in this section, the control gain (hereinafter abbreviated as the non-normal control gain) during the non-normal control is more than the control gain during the normal control (hereinafter abbreviated as the normal control gain). Is increased. Therefore, for example, the normal control gain can be set to a size that can suppress control hunting, and the extraordinary control gain can be set to a size that can provide high responsiveness. Normal control is control when normal braking is performed. This is so-called normal braking control, which is control when the brake operation member is operated in a normal state (at a normal operation speed).
Non-normal control is control other than normal control.For example, emergency brake assist control to assist braking force when emergency braking is performed, slip control performed when the slip state is not the normal state, The turning control or the like performed when a set state is exceeded is applicable. As described above, the non-normal control includes the non-normal braking control that is performed when abnormal braking is performed, and the non-normal driving control that is performed when the running state of the vehicle is not normal regardless of braking. However, any control requires high responsiveness. The extraordinary control can also be referred to as safety control, preventive safety control, high response demand control, and the like. The brake described in this section may be operated by hydraulic pressure or may be operated by electric driving force. For example, in a friction braking device in which a brake is operated by pressing a friction member against a brake rotating body that rotates with wheels, even if the friction member is pressed by hydraulic pressure, the friction member is pressed by an electric driving force. You may. When the friction member is pressed by hydraulic pressure, the brake cylinder corresponds to the actuator, and a hydraulic pressure control valve device capable of controlling the hydraulic pressure of the brake cylinder and a computer for controlling the hydraulic pressure control valve device are used. An actuator control device is configured. When the friction member is pressed by an electric driving force, the electric motor that moves the friction member corresponds to the actuator, and a drive circuit capable of controlling the operation state of the electric motor and a command to the drive circuit. An actuator control device is constituted by a computer or the like to be supplied. The control gain is not limited to the proportional gain, but broadly means “the ratio of the output signal to the input signal”. Therefore, "increase control gain" means not only increasing proportional gain when P control (proportional control) is performed in feedback control, but also I control (integral control) and D control (differential control). When the P / I control, the P / D control, the P / I / D control, or the like, which is a combination of these, is performed, the ratio of the output signal to the input signal is broadly increased.
In addition to the feedback control, increasing the ratio between these signals in feedforward control also applies. In any case, if the ratio of the output signal to the input signal is increased, the change in the input signal is sensitively reflected, and the responsiveness is improved. (2) The actuator control device is provided between one of the high-pressure source and the low-pressure source and the brake cylinder, and the flow of the hydraulic fluid has an opening area determined based on a hydraulic pressure difference before and after the actuator control device and an applied voltage. The brake control device according to claim 1, further comprising: an electromagnetic hydraulic pressure control valve that permits the pressure control; and electromagnetic valve control means that controls the brake hydraulic pressure by controlling the applied voltage. In the electromagnetic hydraulic pressure control valve, when the difference between the front and rear hydraulic pressures is the same, the opening area is made larger when the applied voltage is higher than when it is small. When the opening area is large, the flow rate of the working fluid is larger than when the opening area is small, so that the changing speed of the braking force is increased and the response is improved. The control gain increases. (3) The electromagnetic hydraulic pressure control valve is a valve seat, a valve provided so as to be able to approach and separate from the valve seat, and a biasing means for biasing the valve in a direction to approach the valve seat. And the said valve,
The brake control device according to claim 2, further comprising a seating valve including an electromagnetic driving force applying device that applies an electromagnetic driving force according to the applied voltage in a direction opposite to the urging force of the urging means. A differential pressure acting force, an urging force, and an electromagnetic driving force act on the seating valve in accordance with the difference between the front and rear hydraulic pressures. These three
If the resultant of the two forces acts in a direction to separate the valve from the valve seat, the valve is separated from the valve seat, and the flow of the hydraulic fluid is allowed from the opening between the valve and the valve seat. . If the electromagnetic driving force is increased when the hydraulic pressure difference is the same, the opening area is increased and the flow rate of the working fluid is increased. Increasing the electromagnetic driving force itself or causing the electromagnetic driving force to increase corresponds to an increase in the control gain. (4) The actuator control device controls the actuator based on a brake operation-related amount related to the operation amount of the brake operation member during the normal braking, and the running state of the vehicle in the non-normal state. The brake control device according to any one of the above modes (1) to (3), including: a non-normal control unit that performs control based on at least one of the brake operation-related amount during non-normal braking. During normal braking, the actuator is controlled based on the brake operation-related amount. For example, control to obtain a braking force according to the braking operation force,
That is, the braking effect control is performed. Even if the booster is not provided, the brake operating force can be boosted and the braking force corresponding to the operating force can be output in the same manner as in the case where the booster is provided. It can be referred to as booster control. The brake operation-related amount includes a brake operation amount itself such as an operation force and an operation stroke of a brake operation member, and an amount enabling estimation thereof, that is, a master cylinder hydraulic pressure and the like which change in accordance with the brake operation amount. A brake operation amount corresponding amount, a brake operation amount, a change speed of a brake operation amount corresponding amount, and the like correspond to the amount. The non-normal control unit includes a non-normal driving control unit that controls the vehicle based on the running state of the vehicle during the non-normal operation, and a non-normal control unit that controls the braking operation based on the amount of brake operation performed when the driver performs emergency braking. At least one of the normal braking control means is included. Anti-normal running control means includes anti-lock control means and traction control means for controlling the braking slip state and the driving slip state to be in an appropriate state, and vehicle stability control means for controlling the turning state to be in an appropriate state. And so on. In the non-normal braking control means, for example, a brake operation speed detecting device that detects an operation speed of a brake operation member such as a brake pedal detects that the brake operation member is operated at an operation speed higher than a set operation speed. Emergency braking is performed based on, for example, the master cylinder hydraulic pressure rising gradient detecting device detecting that the rising gradient of the brake fluid pressure is greater than or equal to the set rising gradient. The actuator is controlled based on a brake operation-related amount such as an operation speed and a brake fluid pressure increase gradient, or based on a predetermined control pattern, and the braking force is increased. In this sense, the non-normal braking control means is an emergency braking control means,
It can also be called emergency brake assist control means. In this aspect, during control by the non-normal control means, the control gain is increased to ensure high responsiveness, and during control by the normal braking control means, the occurrence of hunting due to too high responsiveness is good. Is suppressed. (5) The actuator control device according to any one of (1) to (4), including feedback control means for controlling the actuator based on a deviation between a target braking force and an actual braking force. Brake control device. In the brake control device described in this section, feedback control is performed, and the actual braking force is controlled to approximately the target braking force. The target braking force is determined based on the brake operation-related amount during normal braking during normal control, and may be determined based on the non-normal running state of the vehicle during non-normal control, or may be determined based on emergency braking. It may be determined based on the brake operation related amount at the time. (6) A brake hydraulic pressure control device including a hydraulic actuator for operating a brake by hydraulic pressure, and a hydraulic actuator control device for controlling the hydraulic actuator by controlling the brake hydraulic pressure supplied to the hydraulic actuator. In the hydraulic actuator control device,
A brake fluid pressure control device including a control gain determining means for increasing a control gain when controlling the brake fluid pressure during non-normal control from normal control.

[0004]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A brake device including a brake fluid pressure control device as a brake control device according to one embodiment of the present invention will be described below with reference to the drawings. In FIG. 2, reference numeral 10 denotes a brake pedal as a brake operation member, and reference numeral 12 denotes a master cylinder. The master cylinder 12 is of a tandem type having two hydraulic chambers. One of the hydraulic chambers has brake cylinders 18 for left and right front wheels 16 and 17 as driving wheels via a liquid passage 14.
The brake cylinders 26, 28 of the left and right rear wheels 23, 24 are connected to the other hydraulic chamber via a liquid passage 22. This brake device is a front and rear pipe. The brake device is provided with a hydraulic pressure source 30 different from the master cylinder 12. The hydraulic pressure source 30 pressurizes and stores the hydraulic fluid in the master reservoir 32, and includes a pump 34, a motor 36 for driving the pump 34, an accumulator 38, check valves 40 and 42, a pressure switch 44, and the like. The hydraulic fluid in the master reservoir 32 is pumped up by the pump 34, pressurized, and stored in the accumulator 38. When the hydraulic pressure of the accumulator 38 becomes lower than the set pressure, this is detected by the pressure switch 44, and the motor 36 is driven.

An electromagnetic on-off valve 50 is provided upstream of the branch position in the middle of the liquid passage 14, and an electromagnetic on-off valve 52 is provided between the two brake cylinders 18 and 20.
Is provided. Similarly, an electromagnetic on-off valve 54 is provided upstream of the branch position of the liquid passage 22, and the electromagnetic on-off valve 5 is provided between the two brake cylinders 26 and 28.
6 are provided. The solenoid on-off valves 50 and 54 are used to connect and disconnect the brake cylinder to and from the master cylinder 12, and are in a communication state when braking is not performed, but are switched to a disconnected state during normal braking. The solenoid on-off valves 52 and 56 are used to connect and disconnect the two brake cylinders. When the hydraulic pressures of the two brake cylinders can be controlled in common, they are maintained in a communication state. In the case of controlling, it is switched to the cutoff state. Since these solenoid on-off valves 50 to 56 are normally open valves,
In the event of a failure of the electric system or the like including the hydraulic pressure source 30, the communication state is returned to the normal state, all the brake cylinders and the master cylinder 12 are communicated, and the two brake cylinders on the front wheel side and the rear wheel side are communicated with each other. The same hydraulic pressure results.

The hydraulic pressure source 30 is connected to brake cylinders 18, 20 via a fluid passage 60 and brake cylinders 26, 28 via a fluid passage 62. Electromagnetic on-off valves 64 and 66 are provided upstream of the branch positions in the middle of the liquid passages 60 and 62, respectively. When the hydraulic pressure of the brake cylinder is controlled by using the hydraulic pressure of the hydraulic pressure source 30, the solenoid on-off valves 64 and 66 are switched to a communication state. It is a valve. When the electrical system including the hydraulic pressure source 30 fails, the brake system is returned to the cut-off state, so that the hydraulic pressure of the brake cylinder is prevented from returning to the master reservoir 32 through the hydraulic passages 60 and 62.

The brake cylinders 18, 20, 26, 28
, The hydraulic pressure source 30 and the master reservoir 32
, Linear valve devices 70 to 76 are provided, respectively. Since the structures of these linear valve devices 70 to 76 are the same, only the linear valve device 70 will be described, and the description of the other components will be omitted.

As shown in FIG. 3, the linear valve device 70 includes a pressure increasing linear valve 80 as a pressure increasing control valve and a pressure reducing linear valve 82 as a pressure decreasing control valve.
The pressure increasing linear valve 80 is provided in the middle of the liquid passage 60,
The pressure reducing linear valve 82 is provided in the middle of a liquid passage 86 connecting the brake cylinder 18 and the master reservoir 32. The pressure increasing linear valve 80 includes a seating valve 90.
And an electromagnetic urging device 94. The seating valve 90 includes a valve body 100, a valve seat 102, and a valve body 100.
And the valve body 100, the electromagnetic biasing body 104 moving integrally with the
Includes a spring 106 for urging the electromagnetically energized body 104 in a direction of sitting on the valve seat 102. The electromagnetic urging device 94 includes a solenoid 110, a resin holding member 112 that holds the solenoid 110, a first magnetic path forming body 114, and a second magnetic path forming body 116. When a voltage is applied to both ends of the winding of the solenoid 110, a current flows through the winding of the solenoid 110 to form a magnetic field. If the voltage applied to the winding of the solenoid 110 is changed, the magnetic force (hereinafter, referred to as an electromagnetic driving force) acting between the electromagnetically energized member 104 and the second magnetic path forming member 116 changes. . A fitting projection 120 is formed on the end face of the electromagnetically energized body 104 on the side of the second magnetic path forming body 116, and an end surface of the second magnetic path forming body 116 on the side of the electromagnetically energized body 104 is formed. A fitting hole 122 is formed to fit with the fitting protrusion 120 so as to be relatively movable in the axial direction. The spring 106 is attached to the fitting hole 122.

When a voltage is applied to the solenoid 110,
Solenoid 110, first magnetic path forming body 114, electromagnetically biased body 104, second magnetic path forming body 116, first magnetic path forming body 11
4, a magnetic path passing through the solenoid 110 is formed, and the magnetic resistance of the magnetic path between the electromagnetically energized member 104 and the second magnetic path forming member 116 is equal to the magnetic resistance of the magnetically energized member 104 and the second magnetic path. Formed body 11
6 depending on the relative position in the axial direction with respect to. Specifically, if the relative position in the axial direction between the electromagnetically energized body 104 and the second magnetic path forming body 116 changes, the electromagnetically energized body 104 is changed.
Fitting projection 120 and fitting hole 12 of second magnetic path forming body 116
2, the areas of the cylindrical surfaces (portions of the outer peripheral surface of the fitting projection 120 and the inner peripheral surface of the fitting hole 122 that face each other) facing each other change with a small interval. If the electromagnetically energized body 104 and the second magnetic path forming body 116 are simply opposed to each other with a small space between the end faces, the electromagnetically energized body 104 and the second magnetic path forming body 116 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-increasing linear valve 80, the area of the cylindrical surface of the fitting projection 120 and the fitting hole 122 is increased with the approach of the electromagnetic biased body 104 and the second magnetic path forming body 116. Increases, and the magnetic flux passing through this cylindrical surface increases.
The magnetic flux passing through the air gap between the end face of the electromagnetically energized body 104 and the end face of the second magnetic path forming body 116 decreases. as a result,
If the voltage applied to the solenoid 110 is constant, the electromagnetic driving force that urges the electromagnetic biased body 204 in the direction of the second magnetic path forming body 116 causes the electromagnetic biased body 104 and the second magnetic path forming body to move. It is substantially constant irrespective of the relative movement with respect to the axis 116. On the other hand, the electromagnetic biased body 10 by the spring 106
The urging force for urging the fourth member 4 in a direction away from the second magnetic path forming body 116 is formed by the electromagnetically energized body 104 and the second magnetic path forming body 116.
It increases with approach. Therefore, when the urging force based on the hydraulic pressure difference is not acting on the valve element 100, the movement of the electromagnetically energized member 104 in the direction of the second magnetic path forming member 116 is caused by the urging force of the spring 106 and the electromagnetic driving force. Stops when they become equal to each other.

[0010] The magnitude of the electromagnetic driving force acting in the direction in which the electromagnetically energized body 104 approaches the second magnetic path forming body 116 increases with the magnitude of the voltage applied to the winding of the solenoid 110, The relationship between the applied voltage and the electromagnetic driving force can be known in advance. When the applied voltage is increased, the electromagnetic driving force increases, the force for pressing the valve 100 against the valve seat 102 decreases, and the valve 100 easily separates from the valve seat 102. The urging force due to the differential pressure of the hydraulic fluid acting on the valve body 100 is the force acting on the electromagnetically-urged body 104 (which is the combined force of the electromagnetic driving force and the urging force of the spring 106,
(The electromagnetic driving force and the biasing force of the spring 106 are forces opposite to each other).
When the applied voltage is increased, the pressure-increasing linear valve 80 can be opened even if the differential pressure is small, and the valve opening pressure is reduced. Further, when the hydraulic pressure difference is the same, the opening area becomes larger when the applied voltage is higher than when the applied voltage is lower, and the flow rate of the flowing working fluid becomes larger. The change speed of the braking force increases, and the responsiveness increases.

The pressure reducing linear valve 82 is also basically the same as the pressure increasing linear valve 80. When the applied voltage is increased, the valve opening pressure of the pressure reducing linear valve 82 is reduced.
In the pressure reducing linear valve 82, as described later, the urging force of the spring 124 is larger than the spring 106 of the pressure increasing linear valve 80, and is set to a value larger than the value corresponding to the maximum brake cylinder fluid pressure. This is to prevent the backflow of the hydraulic fluid from the brake cylinder to the master reservoir 32. In the configuration of the pressure reducing linear valve 82, the same components as those of the pressure increasing linear valve 80 are denoted by the same reference numerals, and description thereof is omitted.

The brake device has a brake cylinder 1
Pressure sensor 14 for detecting hydraulic pressure of 8, 20, 26, 28
0 to 146, and the master cylinder 12
Is provided with a pressure sensor 148 for detecting the hydraulic pressure.
In the present embodiment, the operation force of the driver's brake pedal 10 is obtained by detecting the hydraulic pressure of the master cylinder 12, and the master cylinder hydraulic pressure corresponds to the brake operation-related amount. Become. A stroke simulator 150 is provided upstream of the electromagnetic on-off valve 50 in the liquid passage 14, and when the electromagnetic on-off valves 50 and 54 are both closed, the stroke of the brake pedal 10 becomes almost zero. Is avoided. A pressure increasing valve 154 is provided in the liquid passage 22 on the upstream side of the electromagnetic switching valve 54. The pressure increasing valve 154 is a mechanical type in which the hydraulic pressure of the hydraulic pressure source 30 is set to the pilot pressure.
When the hydraulic pressure of the pressure becomes low, the pressure is switched from the non-pressure increasing state to the pressure increasing state. The hydraulic pressure of master cylinder 12 is increased and transmitted to wheel cylinders 26 and 28. Further, a brake switch 160 is provided to detect that the brake pedal 10 is depressed. Further, wheel speed sensors 162 to 168 for detecting the rotation speed of each of the wheels 16, 17, 23, 24 are provided, and a braking slip state, a driving slip state, and the like are acquired based on these output signals. Further, a steering sensor 17 for detecting a rotation angle of a steering wheel (not shown)
0, and a yaw rate sensor 171 for detecting the yaw rate of the vehicle is provided.

The brake device is provided with brake fluid pressure control means 172 mainly composed of a computer.
The pressure sensor 140 to 146, the brake switch 160, the wheel speed sensors 162 to 168, the steering sensor 170, the yaw rate sensor 171 and the pressure switch 44 are connected to the input part of the brake fluid pressure control means 172. Are the linear valve devices 70 to 7
6, solenoid of solenoid on-off valve 50-56, 64, 66,
The motor 36 and the like are connected via a drive circuit (not shown). The ROM stores many programs and data such as the linear valve control program represented by the flowchart of FIG.

The operation of the brake device configured as described above will be described. At the time of non-braking, each of the electromagnetic on-off valves 50 to 56, 64, 66, etc. is in the state of FIG. Each of the brake cylinders 18, 20, 26, 28 is communicated with the master cylinder 12 and is isolated from the hydraulic pressure source 30. When the brake pedal 10 is depressed in a normal state, control during normal braking is performed. In the normal braking control, the hydraulic pressure of the brake cylinder is controlled such that a deceleration corresponding to the operating force of the brake operating member is obtained. The electromagnetic on / off valves 50 and 54 are switched to the cutoff state, and the electromagnetic on / off valves 64 and 66 are switched to the communicating state, so that the electromagnetic on / off valves 52 and 56 are kept in the communicating state. Each of the brake cylinders 18, 20, 26, 28 has a hydraulic pressure source 3
The hydraulic pressure of 0 is controlled and transmitted in the linear valve devices 70 to 76, but the brake cylinders 18, 20, 2
The hydraulic pressures 6, 28 are controlled to approximately the same magnitude.

In the present embodiment, feedback control is performed, and the voltage applied to the linear valve devices 70 to 76 is determined so that the difference between the target hydraulic pressure and the actual hydraulic pressure becomes small. The target hydraulic pressure PH ^* is determined by the execution of the normal braking control program to a magnitude that can be obtained in accordance with the driver's operation force of the brake pedal 10, that is, the vehicle deceleration in accordance with the hydraulic pressure of the master cylinder 12. The actual hydraulic pressure PH is detected by the pressure sensors 140 to 146. Deviation Δ between this target hydraulic pressure PH ^* and actual hydraulic pressure PH
P (= PH ^* -PH) is an input signal, and the applied voltage is an output signal. And than P · I · D control for the deviation ΔP is made, the transfer function G between these deviations ΔP and the applied voltage P _E (s) has the formula _{G (s) = K C (} 1 + sT D + 1 / sT _I ). Here, s is a Laplace operator, T _D and T _I are time constants for differentiation and integration, and K _C is
This is a control gain during normal control (hereinafter, referred to as a normal control gain).

When the operation force of the brake pedal 10 becomes excessive with respect to the road surface friction coefficient, antilock control is performed. In the antilock control, the hydraulic pressure of the brake cylinder is controlled so that the braking slip state of each of the wheels 16, 17, 23, and 24 is maintained in an appropriate state.
Since the antilock control is performed for each wheel, the hydraulic pressures of the brake cylinders 18, 20, 26, 28 are controlled independently, and the electromagnetic on-off valves 52, 56 are switched to the shut-off state. The target hydraulic pressure PH ^* at the time of the antilock control is determined by executing the antilock control program.
As described above, the magnitude is determined so that the braking slip state is maintained in an appropriate state. As in the case of normal braking, the deviation ΔP (= PH) between the target hydraulic pressure PH ^* and the actual hydraulic pressure PH
^* -PH) applied voltage P _E of the linear valve devices 70-76 based on is determined. The transfer function G (s) between the deviation ΔP and the applied voltage P _E is represented by the following equation: G (s) = K _A (1 + sT _D + 1 / ST _I ). Here, K _A is the control gain at the time of the anti-lock control (hereinafter, anti-called lock control gain). In the present embodiment, the anti-lock control gain K _A is made larger than the normal control gain K _C. This is to improve responsiveness during antilock control and prevent hunting during normal control.

If the driving slip condition is excessive with respect to the road surface friction coefficient, traction control is performed. In traction control, the front wheels 1
The hydraulic pressures of the brake cylinders 18 and 20 are controlled so that the driving slip state is maintained in an appropriate state.
In this embodiment, the electromagnetic switch valve 50 on the front wheel side is switched to the closed state, the electromagnetic switch valve 64 is switched to the open state, the electromagnetic switch valve 54 on the rear wheel side is maintained in the open state, and the electromagnetic switch valve 66 is maintained in the closed state. Dripping. The target hydraulic pressure PH ^* of the brake cylinders 18, 20 is determined by executing the traction control program. As in the case of the antilock control, the deviation ΔP (= PH) between the target hydraulic pressure PH ^* and the actual hydraulic pressure PH
^* −P H), the P · I · D control is performed, whereby the applied voltage P _E is determined. Deviation ΔP
The transfer function G (s) between the voltage and the applied voltage P _E is represented by the following equation: G (s) = K _T (1 + sT _D + 1 / ST _I ). Here, the traction control gain K _T is set to a value larger than the normal control gain K _C during normal braking. The brake cylinder 2 on the rear wheel side
6 and 28 are cut off from the hydraulic pressure source 30 and the master cylinder 1
2, the brake pedal 10 during control.
Is depressed, the hydraulic fluid of the master cylinder 12 is supplied immediately, thereby avoiding a delay in braking effect.

When the turning state exceeds the set state, vehicle stability control is performed. Spin vacuum and drift out vacuum are calculated based on the steering angle of the steering wheel, the actual yaw rate of the vehicle, and the like. Thus, spin suppression control and drift-out suppression control are performed. For example, when the spin tendency increases during a left turn, the braking force of the turning outer wheel (right wheel) is increased by the braking force of the turning inner wheel (left wheel).
And a moment in the right turning direction is applied. When the drift-out tendency becomes strong, the braking force of the turning inner wheel (left wheel) is increased by the turning outer wheel (right wheel).
And a moment in the left-turn direction is applied.

When the spin tendency becomes excessive during the left turn, the right side braking force is increased on the front wheel side. The electromagnetic valves 50 and 64 are both kept in communication, and the electromagnetic valve 52 provided between the brake cylinders 18 and 20 is switched to the closed state. The hydraulic pressure of the brake cylinder 20 of the right front wheel 17 is controlled while the brake cylinder 18 of the left front wheel 16 is in communication with the master cylinder 12. The target hydraulic pressure PH ^* is determined by executing the vehicle stability control program so as to give a moment that can suppress the spin tendency. Hereinafter, similarly, for the deviation ΔP between the target hydraulic pressure and the actual hydraulic pressure, P
The ID control is performed, and the applied voltage _PE is determined accordingly. The vehicle stability control gain K _V is set to a value larger than the normal control gain K _C. During the spin suppression control, as in the case of the traction control, the brake cylinders 26 and 28 on the rear wheel side, which are the non-control wheels, are also kept in communication with the master cylinder 12, so that the braking effect is reduced. Delays can be avoided.

If the tendency of drift-out becomes excessive during a left turn, the brakes on both wheels on the driving wheel side are increased, and the braking force on the left side on the non-driving wheel side is increased. On the rear wheel side, the hydraulic pressure of the brake cylinder 26 is controlled while the electromagnetic on-off valves 54 and 66 are kept in communication and the electromagnetic on-off valve 56 is kept in a closed state.

Further, when the operation speed of the brake pedal 10 is higher than the set speed, emergency brake assist control is performed. In this case, the target hydraulic pressure PH ^* is determined to a value corresponding to the operating force by executing the emergency brake assist control program. Control gain during brake assist control (gain for brake assist control)
K _{F is} also set to a value larger than the normal control gain K _C.

In the flowchart of FIG. 4, in step 10 (hereinafter abbreviated as S10; the same applies to other steps), any one of antilock control, traction control, vehicle stability control, and emergency brake assist control is performed. It is determined whether one is under control. Whether or not the antilock control is being performed is determined based on whether or not the antilock control flag is set. The antilock control flag is kept set during control by executing the antilock control program,
This is a flag that is kept in a reset state during non-control. Hereinafter, similarly, it is determined whether the vehicle is under traction control, vehicle stability control, or emergency brake assist control based on the set state of these control flags. If neither control is performed,
In S20, the brake switch 16 determines whether or not braking is being performed.
It is determined based on the state of 0. If braking is in progress, the control gain is set to the normal control gain K in S30.
Determined by _C. By executing the normal braking control program, the target hydraulic pressure PH ^* is determined based on the master cylinder hydraulic pressure. The deviation ΔP between the target hydraulic pressure PH ^* and the actual hydraulic pressure PH and the normal control gain K _C S40
In the applied voltage P _E is determined and applied to the linear valve devices 70-76. On the other hand, for example, when the anti-lock control is being performed, in S50, the control gain is determined to be the anti-lock control gain K _A which is larger than the normal control gain K _C. In S60, the deviation ΔP between the anti-target hydraulic pressure determined by the execution of the lock control Purogumu PH ^* and the actual hydraulic pressure, the applied voltage P _E on the basis of the anti-lock control gains K _A is determined, the linear valve device 70-78. Similarly, when the traction control, the vehicle stability control, and the emergency brake assist control are being performed, in S50 and S60, the control gain is determined to be larger than the normal control gain, and the applied voltage is determined accordingly. You. The anti-lock control gain, the traction control gain, the vehicle stability control gain, and the emergency brake assist control gain can be generically referred to, or each of them can be referred to as an unusual control gain.

As described above, in this embodiment, FIG.
The linear valve devices 70 to 76 are controlled by the linear valve control means 176 as shown in FIG. In the linear valve control means 176, the linear valve devices 70 to 7 are controlled based on the deviation between the target hydraulic pressure and the actual hydraulic pressure and the control gain.
6, the target hydraulic pressure is determined according to the execution of the normal braking control program, the antilock control program, the traction control program, the vehicle stability control program, and the emergency brake assist control program. . In the present embodiment, an actuator is constituted by the brake cylinders 18, 20, 26, 28 and the like, and the linear valve devices 70 to
The actuator control device is constituted by a portion for storing and executing the linear valve control program of the brake fluid pressure control means 76 and the brake fluid pressure control means 172. Further, in the actuator control device, S1 of the brake fluid pressure control means 172 is used.
Control gain determining means is constituted by a portion that stores and executes 0, S30, and 50. Further, the normal braking control means 178 is constituted by a part for storing and executing a normal braking control program of the brake fluid pressure control means 172, and includes an antilock control program, a traction control program, a vehicle stability control program, an emergency An unusual control unit 180 is configured by a portion that stores and executes a brake assist control program and the like. The extraordinary control means 180 includes the antilock control means 19
0, traction control means 192, vehicle stability control means 194, emergency brake assist control means 1
96 etc. are included.

In the above embodiment, P · I ·
Although the control gain was provided in common in D control,
A control gain may be separately provided in each of the P control, the I control, and the D control. In this case, at least one of the control gains may be increased. Alternatively, in the feedforward control, the case where the ratio of the output signal to the input signal is increased also corresponds to the fact that the control gain referred to in this specification is increased. Also, not limited to PID control,
The present invention can be applied to other controls such as P control and PI control. Further, the control mode in the vehicle stability control, the mode in the emergency brake assist control, and the like are not limited to those in the above embodiment. In the emergency brake assist control, the target hydraulic pressure may be determined based on not only the brake operation amount but also the operation speed or the like. Further, in the brake control device according to the above-described embodiment, the antilock control, the traction control, the vehicle stability control, and the emergency brake assist control are executable. However, it is not necessary to enable all of them. At least one of the controls can be executed. Further, it is also possible to apply the present invention to a brake device capable of executing other unusual control.

Further, the structure of the actuator is not limited to the one described in the above embodiment, but may be another structure. For example, the actuator may include a plurality of solenoid valves. Further, the present invention is not limited to the hydraulic brake device, and can be applied to an electrically operated brake device. The present invention can be carried out in various modified and improved embodiments.

[Brief description of the drawings]

FIG. 1 is a diagram conceptually showing a brake control device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a brake device including the brake control device.

FIG. 3 is a partial cross-sectional view of the entire linear valve device included in the brake control device.

FIG. 4 is a flowchart showing a part of a linear valve device control program stored in a ROM of the brake control device.

[Explanation of symbols]

 18, 20, 26, 28 Brake cylinder 70-76 Linear valve device 140-148 Pressure sensor 172 Brake fluid pressure control means 176 Linear valve control means 178 Normal braking control means 180 Non-normal control means

Claims (1)

[Claims] 1. A brake control device comprising: an actuator for operating a brake; and an actuator control device for controlling a braking force by controlling the actuator, wherein the actuator control device is controlled when the actuator is controlled. A brake control device including control gain determining means for increasing a gain in non-normal control from normal control.