JPH082398A - Anti-skid brake control system - Google Patents

Abstract

PURPOSE:To prevent the early lock tendency of driven wheels during ABS pressure intensifying control by providing an electronic control device with a TRC cutoff valve control means for controlling the opleration of the TRC cutoff valves for adjusting the braking pressure of the brake cylinder of the driven wheels during ABS. CONSTITUTION:When a timer is judged to have longer time than the set time, the driven wheel side braking pressure is equal to the driving wheel side braking pressure in the held state. TRC cutoff valves 11, 12 are opened in the off state so as to communicate a driven wheel side brake cylinder with brake actuators 13, 14. The on-off control of TRC cutoff valves 23, 24 at the time of ABS pressure intensifying control is then terminated. Since the driven wheel side braking pressure thus rises slower than the driving wheel side braking pressure at the time of ABS pressure intensifying control, rear-side rear wheels 7', 8' which are driven wheels heretofore apt to be locked are hardly locked. The early lock of the rear-side rear wheels 7', 8' is thereby prevented during ABS pressure intensifying control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to at least two axles including a drive shaft for supporting a drive wheel and a driven shaft for supporting a drive wheel. An anti-skid brake control system that is installed in a multi-axle vehicle and controls the brake pressure so as to release the lock when the wheel is locked during braking. Especially, it is driven to eliminate this idle rotation when the drive wheel spins. A traction control system that brakes the wheels to suppress the rotational driving force of the drive wheels is incorporated, and this passage is normally connected to the brake passage that connects the brakes of the drive wheels and the driven wheels. Anti-skid breaker equipped with a traction cut valve that shuts off this passage during traction control by the brake The present invention relates to a control system.

[0002]

2. Description of the Related Art Conventionally, an antiskid brake control system and a traction control system have been adopted as a brake control system for vehicles such as automobiles. Generally, this anti-skid brake control (hereinafter, also referred to as ABS) detects that a wheel tends to lock during braking, weakens the braking force of the wheel to eliminate the locking tendency, and then applies the braking force again. By increasing the value, the control of the vehicle is stabilized, and the brake control is performed so that the braking distance is as short as possible. In addition, traction control (hereinafter, also referred to as TRC) is to weaken the rotational driving force of the drive wheels in order to eliminate the idling of the drive wheels when it is detected that the drive wheels tend to idle when the vehicle starts. Thus, the rotational driving force of the drive wheels is controlled so as to improve the starting performance of the vehicle.

By the way, there is a large-sized vehicle such as a heavy-duty truck, which is configured as a multi-axle vehicle having three or more axles in order to reduce the load applied to the wheels due to the large carrying load. Even in such a multi-axle vehicle, there are cases where the ABS and TRC systems are adopted.

Conventional ABS in such a multi-axle vehicle
As an example of the brake control system adopting the TRC system and the TRC system, there is a brake control system as shown in FIG. 27.
This is a system in which a BS system and a TRC system are integrated together.

As shown in FIG. 27, in the brake control system, the front wheel side has one shaft and the rear wheel side has two shafts, and the first shaft (front wheel side shaft) and the third shaft (rear wheel side rear shaft) are driven shafts. The second shaft (rear wheel side front shaft) is applied to a triaxial vehicle in which the drive shaft is the drive shaft. This brake control system includes wheel speed sensors 3 and 4 that detect the wheel speeds of the left and right front wheels 1 and 2 that are driven wheels, an ABS modulator 5 that adjusts the brake pressure of the front wheels 1 and 2, and a braking force applied to the front wheels 1 and 2. Brake actuator 6 for generating a wheel speed, wheel speed sensors 9 and 10 for detecting wheel speeds of left and right front and rear wheels 7 and 8 which are driving wheels, front and rear wheels 7 and 8
And the brake pressure of the rear left and right rear wheels 7 ', 8'which are driven wheels are adjusted for each of the left and right wheels, respectively.
The BS modulators 11 and 12, the front and rear wheels 7 and 8, and the rear rear wheels 7'and 8 ', brake actuators 13 and 14 for generating braking force, respectively, and a dual brake valve 16 controlled to be opened and closed by a brake pedal 15, and this dual brake valve. 16, air tanks 17 and 17 'that store compressed air (hereinafter, also referred to as air) for brake operation, and solenoid valves that open at the time of TRC to send the air in the air tank 17 to the ABS modulators 11 and 12, respectively. ABS modulator which selectively supplies either one of the air fed through the traction control valves (hereinafter, also referred to as TRC valves) 18 and 19, the dual brake valve 16 and the air fed through the TRC valves 18 and 19. Double check valve feeding 11 and 12 respectively 0,21, brake pipes connected to the brake actuator 13, 14,
It is provided in a portion between the brakes of the front and rear wheels 7 and 8 and the brakes of the rear rear wheels 7'and 8 ', and operates at TRC to brake the rear rear wheels 7'and 8'.
A wheel speed signal is supplied from a traction control cut valve (hereinafter, also referred to as a TRC cut valve) 23, 24 that is shut off from 4 and each wheel speed sensor 3, 4, 9, 10 and each ABS modulator 5, 11, 1
2. ABS / TRC control unit (hereinafter, also referred to as ABS / TRC ECU) that controls each TRC valve 18, 19 and each TRC cut valve 23, 24
2 is provided.

In the brake control system configured as described above, braking for deceleration or vehicle stop is performed as follows. That is, when the brake pedal 15 is depressed during normal braking, the air in the air tank 17 ′ is supplied to the brake actuator 6 through the brake valve 16, the front wheel side air pressure line and the modulator 5. Air pressure is converted into hydraulic pressure by the brake actuator 6, and the hydraulic pressure is introduced into the brake cylinders (not shown) of the left and right front wheels 1 and 2, respectively, and the left and right front wheels 1 and 2 are braked. At the same time, the air in the air tank 17 is supplied to the brake valve 16 and the double check valve 2.
0, 21 and modulators 11, 12 are supplied to the brake actuators 13, 14, respectively. Similar to the front wheel side, these brake actuators 13 and 14 convert the air pressure into hydraulic pressure, and the hydraulic pressure is applied to the left and right front and rear wheels 7 and 8 and the left and right rear rear wheels 7'and 8 ', which are not shown in the drawings. After being introduced into the cylinder, the left and right front and rear wheels 7, 8 and rear rear wheels 7 ', 8'are braked.

On the other hand, the ABS / TRC ECU 22 determines that one of the left and right front wheels 1 and 2 tends to lock based on the wheel speed from the wheel speed sensors 3 and 4 of the front wheels 1 and 2 which are normally driven wheels. If judged, AB for the left and right front wheels 1 and 2
Start S. That is, the ABS / TRC ECU22
Determines that at least one of the left and right front wheels 1 and 2 is in a locking tendency, it sends a control signal to the front wheels 1 and 2.
2 to the ABS modulator 5. This control signal causes the ABS modulator 5 to move to the brake actuator 6
The braking force of the front wheels 1 and 2 is adjusted so that the air pressure introduced into the engine is controlled so that the locking tendency is eliminated.

Similarly, the ABS / TRC ECU 22
When it is determined that the left front and rear wheels 7 are in a locking tendency based on the wheel speeds from the wheel speed sensors 3 and 4 of the front wheels 1 and 2 and the wheel speeds from the wheel speed sensor 9 of the left front and rear wheels 7, The ABS is started for the wheel 7 and the rear left rear wheel 7 '. That is, the ABS / TRC ECU 22 sends the control signal to the ABS
This is sent to the modulator 11, and this ABS modulator 11
Thus, the braking force of the left front wheel 7 and the left rear wheel 7'is adjusted so that the locking tendency is eliminated. Furthermore, ABS / T
When the RC ECU 22 determines that the right front / rear wheel 8 tends to lock based on the wheel speeds from the wheel speed sensors 3 and 4 of the front wheels 1 and 2 and the wheel speed from the wheel speed sensor 10 of the right front / rear wheel 8, ABS is started for the right front wheel 8 and the right rear wheel 8 '. That is, the ABS / TRC ECU 22
Send a control signal to the ABS modulator 12
The modulator 12 adjusts the braking force of the right front wheel 8 and the right rear wheel 8'so that the locking tendency is eliminated.

TRC is the front and rear wheels 7, 8 which are the driving wheels.
The brake control is performed by the brake control for TRC. The TRC by the brake control is performed as follows. That is,
When the propulsive force of the vehicle is increasing, such as when the vehicle starts or suddenly accelerates, AB
The S / TRCECU 22 uses the wheel speed sensors 3, 4, 9, 10
If it is determined that the front and rear wheels 7, 8 that are the driving wheels have a slip tendency based on the calculation result based on the wheel speed signals from the ABS / TRC ECU 22, the ABS / TRC ECU 22 determines that the front and rear wheels 7, 8 and the slip wheels tend to slip. Control signals are output to the modulators 11 and 12, the TRC valves 18 and 19 and the TRC cut valves 23 and 24 corresponding to the rear rear wheels 7'and 8 '.

A control signal from the ABS / TRC ECU 22 turns on and opens the TRC valves 18 and 19, and turns on and closes the TRC cut valves 23 and 24.
Therefore, the air from the air tank 17 passes through the TRC valves 18, 19, the double check valves 20, 21 and the AB.
It is supplied to the brake actuators 13 and 14 through the S modulators 11 and 12, whereby the brake actuators 13 and 14 operate to generate brake pressure. The brake pressure generated in the brake actuators 13 and 14 is supplied only to the brake cylinders of the front and rear wheels 7 and 8 which tend to slip because the TRC cut valves 23 and 24 are closed, and the front and rear wheels 7 and 8 are braked. .
By braking the front and rear wheels 7 and 8, the front and rear wheels 7, 8
The rotational driving force of the front and rear wheels 7 and 8 is suppressed, and as a result, the slip tendency of the front and rear wheels 7 and 8 that tend to slip is eliminated. As a result, the rotational driving force of the front and rear wheels 7, 8 can be more effectively transmitted to the road surface. Further, since the TRC cut valves 23, 24 are closed, the brake pressure generated in the brake actuators 13, 14 is not supplied to the brake cylinders of the rear rear wheels 7 ', 8'which are driven wheels, and the rear rear wheels 7'and 8'are not braked. This prevents loss of the rotational driving force of the front and rear wheels 7 and 8 due to braking of the rear and rear wheels 7'and 8 '.

[0011]

By the way, in such a vehicle in which the front wheel side is uniaxial and the rear wheel side is biaxial,
Left and right front wheels 1, 2 and the left and right front and rear wheels 7, which are the driving wheels,
8 and the load on the left and right rear rear wheels 7 ', 8'is light. Moreover, during braking, the load on the left and right rear rear wheels 7 ', 8'becomes even less due to the nose dive of the vehicle. In particular, the loads applied to the rear left and right rear wheels 7 ', 8'during the sudden braking are significantly reduced.

Therefore, for example, it is determined that one of the left and right front wheels 7 and 8 has a locking tendency, and the ABS is performed on that wheel and on the same side of the left and right rear rear wheels 7'and 8 '. When re-increasing the brake pressure in the process of ABS, or when maintaining the brake pressure from the re-increase,
There is a problem that the wheels on the same side of the left and right rear wheels 7 ', 8'are more likely to lock than the left, right, front wheels 7, 8 earlier.

The present invention has been made in view of such a problem, and an object thereof is to control a traction control cut valve arranged between a brake cylinder of a driving wheel and a brake cylinder of a driven wheel. Accordingly, it is an object of the present invention to provide an anti-skid brake control system capable of preventing the driven wheels from becoming prematurely locked during ABS pressure increase control.

[0014]

In order to solve the above-mentioned problems, the invention of claim 1 supplies a brake cylinder to a drive wheel, a brake cylinder to a driven wheel, and a brake pressure to both brake cylinders at the time of braking. By doing so, a common brake actuator that brakes both the drive wheels and the driven wheels, and a pressure of the working fluid that is supplied and supplied to the brake actuator during braking are referred to as anti-skid brake control (hereinafter referred to as AB
(Abbreviated as S) and the ABS modulator that is adjusted when the brake pedal is pressed during braking.
A brake valve that supplies working fluid to the brake actuator through the S modulator and discharges the working fluid of the brake actuator through the ABS modulator when the brake pedal is released when braking is released, and a traction control (hereinafter referred to as TR).
(Indicated as C), the TRC valve that supplies the working fluid to the brake actuator at the time of normal communication with the brake cylinder of the driven wheel and the brake actuator at the normal time, and the brake cylinder of the driven wheel and the brake actuator at the time of TRC are connected. A TRC cut valve for shutting off, and when at least a lock tendency of the drive wheel is detected during braking, ABS is performed to adjust the pressure of the working fluid supplied to the brake actuator so as to eliminate the lock tendency. The ABS modulator is controlled, and when the idling tendency of the drive wheels is detected, the TRC valve is controlled to supply the working fluid to the brake actuator to perform TRC so as to eliminate the tendency, and to control the sub valve. The brake cylinder of the driving wheel and the In an anti-skid brake control system including an electronic control unit that operates the TRC cut valve that disconnects from an actuator, the electronic control unit adjusts a brake pressure of a brake cylinder of the driven wheel during ABS. A TRC cut valve control means for controlling the operation of the TRC cut valve is provided.

According to a second aspect of the present invention, the TRC cut valve connects the brake cylinder of the driven wheel and the brake actuator when the TRC cut valve is OFF, and disconnects the brake cylinder of the driven wheel and the brake actuator when the TRC cut valve is ON. A control means that is composed of an electromagnetic on-off valve in which two states of OFF are set, and the TRC cut valve control means performs ON / OFF control of the TRC cut valve by duty control during ABS pressure increase control of the ABS modulator. It is characterized by being.

Further, in the invention of claim 3, the TRC cut valve control means turns on and closes the TRC cut valve when the pressure increasing control of the ABS modulator is started, and after the TRC cut valve is turned on. It is characterized in that it is a control means for performing duty control of the TRC cut valve after a set time has elapsed.

Further, in the invention of claim 4, the electronic control device further comprises road surface μ calculating means for calculating a road surface friction coefficient (hereinafter referred to as road surface μ), and the TRC cut valve control means comprises the road surface It is a control means for calculating the duty ratio of the TRC cut valve based on μ.

According to a fifth aspect of the present invention, the TRC cut valve control means controls the wheel speed of the driven wheel, the load of the driven wheel, the load of the drive wheel, and the pedal effort of the brake pedal.
Based on one of the stroke of the brake pedal and the output of the brake valve, the T
The control means is for calculating the duty ratio of the RC cut valve.

According to a sixth aspect of the present invention, when the TRC cut valve is off, it is set in a communication state in which the brake cylinder of the driven wheel and the brake actuator are communicated with each other, and the magnitude of the solenoid current supplied to the solenoid is set. According to the electromagnetic variable throttle valve in which a throttle state that throttles the communication between the brake cylinder of the driven wheel and the brake actuator and a shut-off state that shuts off the brake cylinder of the driven wheel and the brake actuator are set. The electronic control device includes solenoid current setting means for presetting the solenoid current so that the throttle amount of the electromagnetic variable throttle valve becomes a desired amount.
It is characterized in that the TRC cut valve control means is a control means for controlling the TRC cut valve by a set solenoid current preset by the solenoid current setting means during the BS modulator pressure increase control.

Further, according to a seventh aspect of the invention, the TRC cut valve control means closes the TRC cut valve when the pressure increasing control of the ABS modulator is started, and turns on the TRC cut valve by the set solenoid current. Then, the control means is a control means for opening with the throttle amount corresponding to the set solenoid current, and the solenoid current setting means is a control means for setting the set solenoid current after a lapse of a set time after closing the TRC cut valve. It is characterized by that.

Further, in the invention of claim 8, the electronic control device further comprises a road surface μ calculating means for calculating a road surface friction coefficient (hereinafter referred to as road surface μ), and the solenoid current setting means is the road surface μ. It is a control means for setting the set solenoid current based on the above.

According to a ninth aspect of the present invention, the solenoid current setting means controls the wheel speed of the driven wheel, the load of the driven wheel, the load of the driving wheel, the pedal effort of the brake pedal, and the stroke of depression of the brake pedal. And a control means for setting the solenoid current based on one of the outputs of the brake valve.

[0023]

In the present invention having such a structure, AB
By controlling the duty of the TRC cut valve including the electromagnetic on-off valve or controlling the solenoid current that determines the throttle amount of the TRC cut valve including the electromagnetic variable throttle valve during the brake pressure increase control at S. The speed of increasing the brake pressure on the driven wheel side is lower than the speed of increasing the brake pressure on the drive wheel. This allows ABS
Since the brake pressure on the driven wheel side rises more slowly than the brake pressure on the drive wheel side during the pressure increase control of (1), it becomes difficult to lock the driven wheel, which has been apt to be locked in the past. Therefore, AB
Early locking of the driven wheels during the pressure increase control of S is prevented.

Further, according to the present invention, the TRC cut valve is so arranged that, during the control of increasing the brake pressure at the ABS, the start of increasing the brake pressure on the driven wheels is delayed by a set time from the start of increasing the brake pressure on the drive wheels. Controlled. This delays the braking of the driven wheels, which makes it difficult for the driven wheels to lock. Therefore, it is possible to prevent the driven wheels from being locked early during the ABS pressure increase control.

Further, in the present invention, the duty ratio in the duty control of the TRC cut valve, the solenoid current that determines the throttle amount, or the set time of the delay of the start of increasing the brake pressure on the driven wheels is the modulator in the duty control of the modulator. Since the duty ratio, road surface μ, driven wheel speed, driven wheel load, drive wheel load, brake pedal depression force, brake pedal stroke, or brake valve output is calculated, the TRC cut valve is It will be controlled according to the actual situation. Therefore, the control of increasing the brake pressure on the driven wheel side can be performed more appropriately and finely during the ABS pressure increasing control, so that the early locking of the driven wheel can be more appropriately prevented during the ABS pressure increasing control.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. Note that, in describing the present embodiment, FIG.
This will be described using the brake control system shown in. FIG. 1 is a diagram for explaining a first embodiment of an anti-skid brake control method of the present invention, and FIG. 2 is a diagram showing a flow of each process of controlling the TRC cut valves 23, 24 in the first embodiment.

As shown in FIG. 1, in the first embodiment, when the brake pressure increase control in ABS is performed, TR
By controlling the duty of the C-cut valves 23 and 24, the pressure increasing speed of the brake pressure (indicated by a dotted line in FIG. 1) of the rear rear wheels 7'and 8'which are driven wheels is set to the front and rear wheels 7 which are drive wheels.
The brake pressure of No. 8 (shown by the solid line in FIG. 1) is set to be smaller than the pressure increasing speed. Further, in the first embodiment, the brake pressure is maintained after the pressure increase so that the brake pressure on the driven wheel side is finally set to be the same as the brake pressure on the drive wheel side. The control of the TRC cut valves 23 and 24 is controlled by an ABS / TRC ECU which is an electronic control unit as shown in the conventional brake control system of FIG.
It is performed by the TRC cut valve control means 22a in 22.

A twelfth embodiment, which will be described later from this first embodiment
Up to the embodiment, the TRC cut valves 23, 24 use the two-way electromagnetic on-off valve having only two positions of ON / OFF, and any electromagnetic on-off valve known as this two-way electromagnetic on-off valve is used. Can be used.

As shown in FIG. 2, first, in step S1, the rear wheel modulators 11, 1 in the ABS control are controlled.
The pressure increase control of 2 is started. Next, the TRC cut valves 23 and 24 of the brake channels to which the modulators 11 and 12 that are under pressure increase control belong are on / off controlled by duty control. As a result, the brake pressure on the driven wheel side, that is, the rear rear wheels 7 ', 8', rises more slowly than the increase in brake pressure on the drive wheel side, that is, the front and rear wheels 7, 8. Next, in step S3, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, the process returns to step S1 and the processes of steps S1 to S3 are repeated.

When it is determined in step S3 that the ABS pressure increasing control is completed, the modulators 11 and 12 are held and controlled in step S4. As a result, the compressed air from the modulators 11 and 12 is not supplied to the brake actuators 13 and 14, and the brake pressure on the drive wheel side is maintained. Simultaneously with the holding control of the modulators 11 and 12, after the timer T is reset in step S5, the TRC cut valve 2 is reset in step S6.
3, 24 are turned on / off again by duty control. As a result, the brake pressure on the driven wheel side rises more slowly even when the modulators 11 and 12 are held.

Next, after the timer T is counted up in step S7, the timer T is counted in step S8.
Is determined to be greater than the set time. This set time is set to be longer than the time until the brake pressure on the driven wheel side becomes the same as the brake pressure on the drive wheel side. Step S
In 8, it is determined whether or not the timer T is longer than the set time, and when it is determined that the timer T is not longer than the set time, the process proceeds to step S6 and steps S6 to S8.
Each processing of is repeated. As a result, the brake pressure on the driven wheel side continues to rise slowly.

When it is determined in step S8 that the timer T has exceeded the set time, the brake pressure on the driven wheel side is the same as the brake pressure on the driven wheel side in the held state, and the TRC is set in step S9. The cut valves 11 and 12 are turned off and opened, and the driven wheel side brake cylinder is connected to the brake actuators 13 and 14. After that, TRC cut valve 2 during ABS pressure increase control
The on / off control of 3, 24 is completed.

As described above, in this embodiment, since the brake pressure on the driven wheel side rises more slowly than the brake pressure on the drive wheel side during the ABS pressure increasing control, the rear wheel which is apt to be locked by the conventional It becomes difficult for the rear wheels 7 ', 8'to lock. Therefore, the rear rear wheels 7 ', 8 are controlled during the ABS pressure increasing control.
Early locking of ´ will be prevented.

FIG. 3 is a diagram for explaining the second embodiment of the present invention. As shown in FIG. 3, in the second embodiment, the TRC cut valves 23 and 24 are duty-controlled to control the driven wheels in the same manner as the above-described first embodiment during the brake pressure increase control in the ABS. There is a rear wheel 7
Set the pressure increase rate of the brake pressures of ′ and 8 ′ (shown by the dotted line in FIG. 3) to be lower than the pressure increase rate of the brake pressure of the front and rear wheels 7, 8 that are the drive wheels (shown by the solid line in FIG. 3) In addition to this, in addition to this, in order to keep the brake pressure of the rear rear wheels 7 ', 8'lower than the brake pressure of the front and rear wheels 7, 8 in the state of holding the brake pressure when shifting from the increased pressure. It is set.

FIG. 4 is a diagram showing a flow of each process of controlling the TRC cut valves 23 and 24 in the second embodiment. As shown in FIG. 4, first, in step S10, steps S1 to S of A (illustrated in FIG. 2) of the first embodiment are performed.
Each processing of 3 is performed. Next, when it is determined in step S10 that the ABS pressure increasing control is completed, the modulators 11 and 12 are held and controlled in step S11. As a result, the compressed air from the modulators 11 and 12 is not supplied to the brake actuators 13 and 14, and the brake pressure on the drive wheel side is maintained. Further, in step 12, the TRC cut valves 23 and 24 are turned on and closed simultaneously with the holding control of the modulators 11 and 12. As a result, the brake cylinder on the driven wheel side is completely cut off from the brake actuators 13 and 14 and the brake cylinder on the drive wheel side, and the brake pressure on the driven wheel side is held at a value lower than the holding pressure of the brake pressure on the drive wheel side. It

As described above, in the present embodiment, not only the brake pressure on the driven wheel side rises more slowly than the brake pressure on the drive wheel side, but also the holding pressure after the brake pressure on the driven side is increased is on the drive wheel side. Since it is lower than the brake pressure of, the rear rear wheels 7 ', 8'which are driven wheels become more difficult to lock,
The early locking of the rear rear wheels 7'and 8'during the brake pressure increase control can be prevented more reliably.

FIG. 5 shows the TRC in the third embodiment of the present invention.
It is a figure which shows the flow of each process of control of the cut valves 23 and 24. In the third embodiment, the duty ratio in the duty control of the TRC cut valves 23, 24 in the first embodiment or the second embodiment described above is set in association with the duty ratio in the duty control of the modulators 11, 12. I have to.

That is, as shown in FIG. 5, first, when the pressure increasing duty control of the modulators 11 and 12 is started in step 13, the duty ratio of the pressure increasing duty control of the modulators 11 and 12 is multiplied by a constant A in step S14. As a result, the TRC cut valve 23,
The duty ratio in the duty control of 24 is determined. Then, in step S15, the duty of the TRC cut valves 23 and 24 is controlled based on the determined duty ratio. Then, in step S16, A
If it is determined whether the BS pressure increase control is completed or not, and if it is determined that the ABS pressure increase control is not completed, step S13.
Then, the process of steps S13 to S16 is repeated.

When it is determined in step S16 that the ABS pressure increasing control is completed, the first control is performed in step S17.
The processes of steps S4 to S9 of B (illustrated in FIG. 2) of the embodiment or the processes of steps S11 to S12 of C (illustrated in FIG. 4) of the second embodiment are performed.

In the third embodiment, the duty control of the TRC cut valves 23 and 24 is performed in association with the duty control of the modulators 11 and 12, so that the TRC cut valves 23 and 24 can be operated more accurately. The duty is controlled.

FIG. 6 is a diagram for explaining the fourth embodiment of the present invention. As shown in FIG. 6, in the fourth embodiment, the start of increasing the brake pressure on the driven wheel side at the start of ABS pressure increase is a predetermined time t ₁ from the start of increasing the brake pressure on the drive wheel side.
It is set to be delayed only. Further, the pressure increasing speed of the brake pressure on the driven wheel side after the pressure increasing is started is set to be the same as the pressure increasing speed of the brake pressure on the driving wheel side (the state shown in FIG. 6), or the first embodiment described above. Similarly, the speed is set to be smaller (not shown) than the speed of increasing the brake pressure on the drive wheel side. Furthermore, in the fourth embodiment, the brake pressure is maintained after the pressure increase so that the brake pressure on the driven wheel side is finally set to be the same as the brake pressure on the drive wheel side.

FIG. 7 is a diagram for explaining the fifth embodiment of the present invention. As shown in FIG. 7, in the fifth embodiment, similarly to the fourth embodiment described above, when the ABS pressure increase is started, the brake pressure on the driven wheel side is started to be increased. With a delay of a predetermined time t _{1, the} speed of increasing the brake pressure on the driven wheel side after starting the pressure increase is set to be the same as the speed of increasing the brake pressure on the drive wheel side (state shown in FIG. 7). Alternatively, similarly to the above-described first embodiment, it is set (not shown) to be smaller than the pressure increasing speed of the brake pressure on the drive wheel side. Furthermore, in the fifth embodiment, the brake pressure on the driven wheel side is finally set to be lower than the brake pressure on the drive wheel side by maintaining the brake pressure after the pressure increase.

FIG. 8 shows the TRC cut valves 23 and 24 in the fourth and fifth embodiments when the speed of increasing the brake pressure on the driven wheel side is set smaller than the speed of increasing the brake pressure on the drive wheel side. It is a figure which shows the flow of control.

As shown in FIG. 8, first, when the ABS pressure increasing control of the modulators 11 and 12 is started in step S18, the brake actuators 13 and 14 start increasing the brake pressure. At the same time, the TRC cut valves 23 and 24 are turned on and closed in step S19. As a result, the brake pressure on the drive wheel side starts to increase, but the brake pressure on the driven wheel side does not increase. Furthermore, TRC
Simultaneously with the closing of the cut valves 23, 24, the timer T ₁ is reset in step S20, and the timer T ₁ is counted up in step S21.

Next, in step S22, the timer T ₁
Is greater than the set time t _l , the timer T ₁
When it is determined that is not longer than the set time t ₁ , the process proceeds to step S21, and the processes of steps S21 and S22 are repeated. That is, the TRC cut valve 23,
The time after the closing of 24 is counted. In step S22, when the timer T ₁ becomes equal to or longer than the set time t ₁ , duty control of the TRC cut valves 23 and 24 is started in step S23. As a result, after the brake pressure increase on the drive wheel side is started, the brake pressure increase on the driven wheel side is started after a delay of the set time t ₁ . The speed of increasing the brake pressure on the driven wheel side is smaller than the speed of increasing pressure on the drive wheel side.

Next, in step S24, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, the process of step S24 is repeated. That is, the ABS pressure increasing control is continuously performed. When it is determined in step S24 that the ABS pressure increasing control is completed, in step S25, in the case of the above-described fourth embodiment, steps S4 to S9 of B (illustrated in FIG. 2) of the first embodiment are performed, In the case of the above-mentioned fifth embodiment, step S1 of C (illustrated in FIG. 4) of the second embodiment.
1 to S12 are performed.

FIG. 9 is a TRC cut valve 23, 24 for performing ABS pressure reduction control after holding brake pressure in the case of performing C of the second embodiment in the above-described second embodiment and third to fifth embodiments. It is a figure which shows an example of the flow of control of.

As shown in FIG. 9, first, when the ABS pressure reduction control of the modulators 11 and 12 is started in step S26, the brake actuators 13 and 14 start to reduce the brake pressure. As a result, the brake pressure on the drive wheel side begins to decrease, but the brake pressure on the driven wheel side does not start to decrease because the TRC cut valves 23 and 24 are closed. Simultaneously with the start of the ABS pressure reducing control of the modulator 11 and 12, together with the timer T ₂ is reset in step S27, the timer T ₂ at step S28
Is counted up. Next, it is determined whether the timer T ₂ is larger than the set time t ₂ in step S29 is the timer T ₂ is not greater than the set time t _2, the process proceeds to step S28, step S28 and S29 The process of is repeated. That is, the time after the pressure reduction control of the modulators 11 and 12 is started is counted.
During this time, the brake pressure on the drive wheel side is continuously reduced.

When the timer T ₂ becomes equal to or longer than the set time t ₂ in step S29, the TRC is set in step S30.
The cut valves 23 and 24 are turned off and opened. As a result, after the brake pressure on the drive side is started to be reduced, the brake pressure on the driven wheel side is also reduced after a delay of the set time t ₂ . Next, in step S31, it is determined whether or not the ABS pressure reducing control is completed. If it is determined that the ABS pressure reducing control is not completed, the process of step S31 is repeated. During this time, both the brake pressure on the drive wheel side and the brake pressure on the driven wheel side are continuously reduced.

When it is determined in step S31 that the ABS pressure reducing control is completed, the modulators 11 and 12 are held and controlled in step 32, and the ABS pressure reducing control process is completed.

FIG. 10 shows the TR in the sixth embodiment of the present invention.
It is a figure which shows the flow of each process of control of C cut valve 23,24. In the sixth embodiment, the duty ratio of the duty control of the TRC cut valves 23, 24 in the fourth or fifth embodiment is set to the modulators 11, 12
The duty ratio is set in relation to the duty ratio.

That is, as shown in FIG. 10, when the pressure increasing duty control of the modulators 11 and 12 is first started in step 33, the duty ratio of the pressure increasing duty control of the modulators 11 and 12 is multiplied by a constant A in step S34. By doing so, TRC cut valve 2
The duty ratio of the duty control of 3,24 is determined. Then, in step S35, steps S19 to S25 of D (illustrated in FIG. 8) of the fourth or fifth embodiment.
Each processing of is performed.

FIG. 11 shows the TR in the seventh embodiment of the present invention.
It is a figure which shows the flow of each process of control of C cut valve 23,24. In the seventh embodiment, the above-mentioned first embodiment,
In the second embodiment, the fourth embodiment, and the fifth embodiment, T
The duty ratio of the duty control of the RC cut valves 23, 24 is set based on the friction coefficient (hereinafter also referred to as μ) of the road surface. As an example of setting the duty ratio, for example, when the road surface μ is high, the duty ratio is set to a large value, when the road surface μ is medium, the duty ratio is set to a medium value, and when the road surface μ is If it is low, the duty ratio is set to a small value. The setting of the duty ratio based on the road surface μ is not limited to this.
It goes without saying that any method of setting the duty ratio may be used as long as it is based on

The flow of the seventh embodiment will be described in detail. First, as shown in FIG. 11, the road surface μ is calculated in step S36. This road surface μ is a wheel speed sensor 3, 4 or 9 ', 10' (wheels of rear rear wheels 7 ', 8', which detects the wheel speed of front wheels 1, 2 or rear rear wheels 7 ', 8'which are driven wheels. The speed sensors 9'and 10 'have not been provided conventionally, but are shown in FIG. 27 for convenience sake) based on the wheel speed detected by the road surface μ calculating means 22b (see FIG. 27 is shown for convenience). Next, in step S37, the duty ratio of the duty control of the TRC cut valves 23 and 24 is set based on the calculated road surface μ by a setting method based on the road surface μ such as the above-described duty ratio setting method. Then, in step S38, each processing of steps S1 to S9 of E (shown in FIG. 2) of the first embodiment or step S of F (shown in FIG. 4) of the second embodiment described above.
10 to S12, or steps S18 to S25 of G (shown in FIG. 8) of the fourth and fifth embodiments.
Or each of the above processing is performed.

Generally, as the road surface μ is lower, the driven wheels are more likely to be locked. Therefore, by setting the duty ratio based on the road surface μ in this way, it is possible to more appropriately control the brake pressure on the driven wheel side in the ABS. Like

FIG. 12 shows the TR in the eighth embodiment of the present invention.
It is a figure which shows the flow of each process of control of C cut valve 23,24. In the eighth embodiment, the TRC cut valves 23, 24 in the third and sixth embodiments described above are used.
The constant A for calculating the duty ratio of the duty control is set based on the road surface μ. As an example of setting the duty ratio, for example, when the road surface μ is high, the constant A is set to a large value, when the road surface μ is medium, the constant A is set to a medium value, and the road surface μ is If it is low, the constant A is set to a small value. The setting of the constant A based on the road surface μ is not limited to this, and it goes without saying that any method of setting the constant A may be used as long as it is based on the road surface μ.

The flow of the eighth embodiment will be described in detail. First, as shown in FIG. 12, the road surface μ is calculated in step S39. This road surface μ is calculated by the same method as in the case of the seventh embodiment described above. Next, step S40.
In, the constant A is determined based on the calculated road surface μ by a determination method based on the road surface μ such as the above-described constant A determination method. Then, in step S41, each processing of steps S13 to S17 of H (illustrated in FIG. 5) of the third embodiment or each of steps S33 to S35 of I (illustrated in FIG. 10) of the sixth embodiment. Either is done.

Also in the eighth embodiment, the same effect as that of the seventh embodiment can be obtained. FIG. 13 is a diagram showing a flow of each process of controlling the TRC cut valves 23 and 24 in the ninth embodiment of the present invention. In the ninth embodiment, the TRC cut valve 2 is used in the above-described fourth and fifth embodiments.
The reference set time t ₁ for starting the duty control of 3, 24 is determined based on the road surface μ. As an example of determining the set time t ₁ , for example, when the road surface μ is high, the set time t ₁ is set to a small value,
When the road surface μ is medium, the set time t ₁ is set to a medium value, and when the road surface μ is low, the set time t ₁ is set to a large value. Determination of setting time t ₁ based on the road surface mu is without having to be limited to this, as long as it is based on the road surface mu, that any configuration may be in a way of determining the time t ₁ of course.

The flow of the ninth embodiment will be specifically described. First, as shown in FIG. 13, the road surface μ is calculated in step S42. This road surface μ is calculated by the same method as in the case of the seventh embodiment described above. Next, step S43.
At the set time t based on the calculated road surface μ
₁ is determined by a determination method based on the road surface μ, such as the determination method of the set time t ₁ described above. And step S4
In step 4, each processing of steps S18 to S25 of G (shown in FIG. 8) of the above-described fourth or fifth embodiment is performed.

Also in the ninth embodiment, almost the same effect as that of the seventh embodiment can be obtained.

FIG. 14 shows T in the tenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the tenth embodiment, the duty ratio in the first to sixth embodiments described above, the calculation of the constant A or set time t _1,, the load detection meter 38 ', such as load sensors, 39
′ (For convenience, shown in the brake control system of FIG. 27), the load of the rear rear wheels 7 ′, 8 ′, which are driven wheels, or the drive detected by the load detectors 38, 39 (shown in FIG. 27). The load of the front and rear wheels 7 and 8 which are wheels, or the pedal effort of the brake pedal 15 detected by the pedal force meter 40 (shown in FIG. 27) and the brake pedal 15 detected by the stroke sensor 41 (shown in FIG. 27). The duty ratio, the constant A, or the set time t ₁ is determined based on either the depression stroke or the output of the brake valve 16 detected by the pressure sensor 42 (shown in FIG. 27). As a specific example of calculating the duty ratio, the constant A, or the set time t ₁ , for example, when the load of the driven wheel is small, the duty ratio is set small, the constant A is set small, or the set time t ₁ is set large. When the load is set, or when the load on the driving wheels is large, the duty ratio is set to a large value, the constant A is set to a large value, or the set time t ₁ is set to a small value, or the pedal effort of the brake pedal 15, the brake pedal stroke and the brake valve are set. When the brake input such as output or the brake input increasing speed is large, the duty ratio is set small, the constant A is set small, and the set time t ₁ is set large. Further, when the brake input or the brake input increasing speed is high, the duty ratio is set small, the constant A is set small, or the set time t ₁ is set large.

As shown in FIG. 14, in step S45, the driven wheel load is detected, or the drive wheel load is detected.
Alternatively, either the depression force of the brake pedal 15, the depression stroke of the brake pedal 15, or the output of the brake valve 16 is detected.

Next, in step S46, each processing of steps S37 to S38 of J (illustrated in FIG. 11) of the seventh embodiment or steps S40 to S41 of K (illustrated in FIG. 12) of the eighth embodiment. Each processing or steps S43 to S44 of L (illustrated in FIG. 13) of the ninth embodiment
Or each of the above processing is performed. In that case, the calculation of the duty ratio of the TRC cut valve 23, 24 in step S37, the determination of the constants A in step S40, and the decision set time t ₁ in step S43, the driven wheels 7 ', a load of 8', the drive wheel Load of 7,8, pedal force of brake pedal 15,
This is performed based on the detected stroke value of the brake pedal 15 or the output value of the brake valve 16.

Also in the tenth embodiment, almost the same effect as that of the seventh embodiment can be obtained. FIG. 15 is a diagram showing a flow of each process of controlling the TRC cut valves 23 and 24 in the eleventh embodiment of the present invention. In this eleventh embodiment,
The wheel speed V _a of the driven wheel and the wheel speed V _{b of the} driving wheel are compared, and the TRC cut valves 23 and 24 are duty cycled so that the wheel speed V _a of the driven wheel and the wheel speed V _{b of the} driving wheel become the same. On / off control is performed by control. That is, as shown in FIG. 15, when the modulator pressure increase control is started in step S47, the wheel speed signals from the wheel speed sensors 9 ', 10' of the rear rear wheels 7 ', 8'are changed to ABS / TRC E.
The wheel speed difference calculating means 22c (illustrated for convenience in FIG. 27) supplied to the CU 22 and provided in the ABS / TRC ECU 22 calculates the wheel speed V _a of the driven wheels in step S48 and also drives in step S49. wheel speed V _b of the wheel been calculated, further the difference between these wheel speeds V _b and the wheel speed V _a (V _b -V _a) is calculated. Then, whether the difference (V _b -V _a) is larger than the set value is determined in step S50.

[0065] If the difference (V _b -V _a) is determined to be larger than the set value, close TRC cut valve 23, 24 is turned on in step S51. Accordingly, when the larger wheel speed V _b of the driving wheels is boosted only braking pressure of the drive wheel, the wheel speed V _b of the driving wheel is driven wheel speed V _a
Is controlled to be the same as. Also the difference (V _b -V _a) is not greater than the set value, TRC cut valve 23, 24 in step S52 is opened is turned off. Thus, when direction of the wheel speed V _a of the driven wheels is large, the braking pressure of the drive wheels and the driven wheels are boosted together.

Next, in step S53, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, then the routine proceeds to step S47,
Each processing of steps S47 to S53 is repeated.
When it is determined that the ABS pressure increasing control is completed, step S
At 54, each processing of steps S4 to S9 of B (illustrated in FIG. 2) of the first embodiment is performed. In the eleventh embodiment, almost the same effect as that of the first embodiment can be obtained.

FIG. 16 shows T in the twelfth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the twelfth embodiment, on the basis of the difference between the wheel speed V _a of the driven wheel and the wheel speed V _b of the driving wheels (V _b -V _a), the duty control of the ABS pressure increasing control time of the TRC cut valve duty I try to determine the ratio. As an example of the determination of the duty ratio, in the example the difference (V _b -V _a) a small duty ratio is large, also the difference (V _b -V _a) is the duty ratio when the value of the middle, the difference ( setting the duty ratio to a large when V _b -V _a) is small. Of course, the determination of the duty ratio may be any method as long as the determination method based on other than this difference (V _b -V _a).

The thirteenth embodiment will be described concretely.
When pressure rose modulator control is started at first step S55, as shown in FIG. 16, step S with the wheel speed V _a of the driven wheels is calculated in step S56
After the wheel speed V _b of the driving wheels is calculated in 57, the difference between the wheel speed V _a of the wheel speed V _b and the driven wheel of the driving wheels (V _b -V _a) is calculated in step S58. Next, in step S59, the calculated difference duty ratio in duty control of the TRC cut valve 23 on the basis of (V _b -V _a) is, for example, the aforementioned difference, such as a duty ratio determining method (V _b -V _a ) Based on the determination method based on Next, in step S60, the TRC cut valves 23 and 24 are on / off controlled by duty control based on the determined duty ratio.

Next, at step 61, it is judged if the ABS pressure increasing control is completed or not, and if it is judged that the ABS pressure increasing control is not completed, then the routine proceeds to step S55,
Each processing of steps S55 to S61 is repeated.
Further, when it is determined that the ABS pressure increasing control is completed, each processing of steps S4 to S9 of B (illustrated in FIG. 2) of the first embodiment is performed in step S62. This 12th
In the embodiment, the brake pressure of the driven wheels is controlled based on the wheel speed of the driven wheels, so that more appropriate control can be performed.

FIG. 17 shows T in the thirteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the above-mentioned first to twelfth embodiments, the control of the TRC cut valves 23 and 24 when the ON / OFF valves are used for the TRC cut valves 23 and 24 has been described.
In the embodiment, the control of the TRC cut valves 23, 24 in the case of using the linear solenoid variable throttle valve in which the throttle gradually increases as the supply current increases and finally fully closed in the TRC cut valves 23, 24. Is an example of.
The linear solenoid variable throttle valve may be any solenoid valve whose throttle increases in proportion to the current supplied to the solenoid.

In the thirteenth embodiment, almost the same control as in the first embodiment is performed. That is, the TRC cut valves 23 and 24, which are linear solenoid variable throttle valves, are controlled so that the brake pressure characteristics of the driven wheels shown in FIG. 1 can be obtained during the ABS pressure increase control and when the ABS pressure is maintained. ing.

As shown in FIG. 17, first, step S63.
In the ABS / TRC ECU 22, the solenoid current setting means 22d provided in the ABS / TRC ECU 22 sets the set solenoid current C of the TRC cut valves 23, 24, and in step S64, the set solenoid current C of the TRC cut valves 23, 24 is set. Turned on. As a result, the TRC cut valves 23 and 24 are set to the throttle amount corresponding to the set solenoid current C. Next, in step S65, the ABS pressure increase control of the modulators 11 and 12 is performed, and the brake pressure on the driven wheel side is slowly increased by the set throttle amount as compared with the brake pressure increase on the drive wheel side. Next, in step S66, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, the process returns to step S65 and the processes of steps S65 and S66 are repeated.

When it is determined in step S66 that the ABS pressure increasing control is completed, the modulators 11 and 12 are held and controlled in step S67. This allows
Compressed air from the modulators 11 and 12 is no longer supplied to the brake actuators 13 and 14, and the brake pressure on the drive wheel side is maintained. Simultaneously with the holding control of the modulators 11 and 12, the timer T is reset in step S68, and then the timer T is counted up in step S69. Next, in step S70, it is determined whether the timer T is longer than the set time. This set time is set to be longer than the time until the brake pressure on the driven wheel side becomes the same as the brake pressure on the drive wheel side based on the set throttle amount. Next, in step S70, it is determined whether or not the timer T is longer than the set time, and when it is determined that the timer T is not longer than the set time, the process proceeds to step S69, and the processes of steps S69 and S70 are repeated. As a result, the brake pressure on the driven wheel side continues to rise slowly.

If it is determined in step S70 that the timer T has exceeded the set time, the brake pressure on the driven wheel side is the same as the brake pressure on the driven wheel side in the held state, and the TRC is set in step S71. The cut valves 11 and 12 are turned off and the throttle amount is 0, that is, the valve is fully opened. The brake cylinder on the driven wheel side is communicated with the brake actuators 13 and 14. After that, the control of the TRC cut valves 23 and 24 during the pressure increase control is completed, and the process returns to the start.

FIG. 18 shows T in the fourteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the fourteenth embodiment, the modulators 11 and 12 are duty-controlled during the ABS pressure increasing control, and the thirteenth embodiment described above is performed based on the duty ratio.
The set solenoid current C of the TRC cut valves 23 and 24 in the embodiment is set. As an example of the setting of the set solenoid current C, for example, when the modulator duty ratio is large, the set solenoid current C is set small, and when the modulator duty ratio is medium, the set solenoid current C is set to the medium position. When the ratio is small, the set solenoid current C is set large. The setting solenoid current C may be set by any setting method as long as the setting solenoid current C is set based on the modulator duty ratio.

That is, as shown in FIG. 18, first, in step S72, the duty ratio of the modulator pressure increasing duty control is determined, and in step S73, the setting solenoid current C of the TRC cut valve is set based on this duty ratio, for example, as described above. It is set by a predetermined setting method based on the modulator duty ratio, such as the setting method of the solenoid current C. Then, each processing of steps S64 to S71 of M (illustrated in FIG. 17) of the thirteenth embodiment is performed by the set solenoid current C that is set.

FIG. 19 shows T in the fifteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. The fifteenth embodiment performs almost the same control as the fifth embodiment. That is, at the start of ABS pressure increase, the start of pressure increase of the driven wheels is delayed from the start of pressure increase of the drive wheels by the set time t _{1, and the} pressure increase speed of the driven wheels becomes smaller than the pressure increase speed of the drive wheels. , TRC cut valves 23, 24 are controlled.

In the fifteenth embodiment, as shown in FIG. 19, first, in step S75, each processing of steps S18 to S22 of N (shown in FIG. 8) of the fourth and fifth embodiments is performed. When the timer T ₁ becomes equal to or longer than the set time t ₁ in step S22, TR is set in step S76.
The set solenoid current C of the C cut valves 23 and 24 is set, and the set solenoid current C of the TRC cut valves 23 and 24 set in step S77.
Is turned on by. This allows the TRC cut valve 2
3, 24 are set to the throttle amount corresponding to the set solenoid current C, and the brake pressure on the driven wheel side increases more slowly than the brake pressure on the drive wheel side due to the set throttle amount. Next, in step S78, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, the process of step S78 is repeated.

When it is determined in step S78 that the ABS pressure increasing control is completed, the modulators 11 and 12 are held and controlled in step S79. This allows
Compressed air from the modulators 11 and 12 is no longer supplied to the brake actuators 13 and 14, and the brake pressure on the drive wheel side is maintained. Simultaneously with the holding control of the modulators 11 and 12, the TRC cut valves 23 and 24 are fully closed in step S80, and the brake pressure on the driven wheel side does not rise any further. That is, the brake pressure on the driven wheel side is held at a holding pressure lower than the holding pressure of the brake pressure on the driving wheel side.

FIG. 20 shows T in the sixteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the sixteenth embodiment, the road surface μ is calculated and the setting solenoid current C of the TRC cut valve is set based on the road surface μ. As an example of the setting of the set solenoid current C, for example, when the value is high μ, the set solenoid current C is set small, that is, the diaphragm amount is set small. When the value is low, the set solenoid current C is set large, that is, the diaphragm amount is set large. This setting solenoid current C is set by the road surface μ
Other methods may be used as long as the method is based on.

As shown in FIG. 20, the road surface μ is calculated in the same manner as described above in step S81, and the set solenoid current C of the TRC cut valves 23 and 24 is calculated based on this road surface μ in step S82, for example. It is set by a predetermined method based on the road surface μ such as a method. Next, in step S83, M of the thirteenth embodiment
Each processing of steps S64 to S71 (illustrated in FIG. 17) or each processing of steps S77 to S80 of O (illustrated in FIG. 19) of the fifteenth embodiment is performed.

FIG. 21 shows T in the seventeenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the seventeenth embodiment, the road surface μ is calculated, and the set time t ₁ for starting the boosting of the brake pressure on the driven wheels during ABS is determined based on the road surface μ. As an example of determining the set time t ₁ ,
For example, when the road surface height is μ, the set time t ₁ is set small,
When the road surface μ is set, the set time t ₁ is set to an intermediate value, and when the road surface is low μ, the set time t ₁ is set to be large. Any other method may be used to determine the set time t ₁ as long as the method is based on the road surface μ.

As shown in FIG. 21, the road surface μ is calculated in the same manner as described above in step S84, and the set time t is calculated based on this road surface μ in step S85.
₁ is determined by a predetermined method based on the road surface μ, such as the method described above. Next, in step S86, steps S75 to S8 of P (illustrated in FIG. 19) of the fifteenth embodiment.
Each processing of 0 is performed.

FIG. 22 shows T in the eighteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the eighteenth embodiment, setting of the TRC cut valve 23 based on the difference between the wheel speed V _a of the wheel speed V _b and the driven wheel of the driving wheels (V _b -V _a) solenoid current C
Is set. As an example of the setting of the setting the solenoid current C, for example, the difference (V _b -V _a) is greater setting the solenoid current C is greater, that is set large aperture value, the difference (V _b -V _a) is medium the middle set solenoid current C time, i.e. set the aperture amount to moderate the difference when (V _b -V _a) is small decrease the solenoid current C, i.e. setting a small aperture amount. Configuring this setting the solenoid current C may be in any other way as long as it is a method based on the difference (V _b -V _a).

[0085] with the wheel speed V _a of the driven wheels is calculated in step S87 as shown in FIG. 22, the wheel speed V _b of the drive wheels is calculated in step S88, further wheel speed V _b of the drive wheel in step S89 the difference between the wheel speed V _a of the driven wheels (V _b -V _a) is calculated as. Is then set in a predetermined manner based on the differences in how such a solenoid current of TRC cut valve, for example, above (V _b -V _a) in step 90. Next, at step S91, the TRC cut valves 23 and 24 set the solenoid current C.
Is turned on to open the throttle amount corresponding to the set solenoid current C, and the pressure increase of the modulators 11 and 12 is controlled in step S92. As a result, the brake pressure on the drive wheel side is increased, and the brake pressure on the driven wheel side is increased at a pressure increase rate lower than the pressure increase rate on the drive wheel side. Next, in step S93, it is determined whether or not the ABS pressure increasing control is completed. If it is determined that the ABS pressure increasing control is not completed, the process proceeds to step S87, and thereafter, the processes of steps S87 to S93 are repeated. .

If it is determined in step S93 that the ABS pressure increasing control has been completed, the first operation is performed in step S94.
Steps 67 through S of Q (illustrated in FIG. 17) of the third embodiment.
Each processing of 71 is performed.

FIG. 23 shows T in the nineteenth embodiment of the present invention.
It is a figure which shows the flow of each process of control of RC cut valve 23,24. In the nineteenth embodiment, the solenoid current C is set and the set time t ₁ is determined in the sixteenth and seventeenth embodiments described above by using the tenth embodiment (FIG. 1).
Similar to 4), the load of the rear rear wheels 7 ', 8'which are driven wheels, the load of the front and rear wheels 7, 8 which are driving wheels, the pedal force of the brake pedal 15, the stroke of the brake pedal 15, or the brake valve. It is set and determined based on any one of 16 outputs.

As shown in FIG. 23, in step S95, the driven wheel load is detected, or the drive wheel load is detected.
Alternatively, either the depression force of the brake pedal 15, the depression stroke of the brake pedal 15, or the output of the brake valve 16 is detected.

Next, in step S96, steps S82 to S83 of R (illustrated in FIG. 20) of the 16th embodiment.
Or each processing of steps S85 to S86 of S (illustrated in FIG. 21) of the seventeenth embodiment. In that case, the decision set time t ₁ of the TRC cut valve settings solenoid current C in and step S85 in step S82, the driven wheels 7 ', load 8', the load of the driving wheels 7 and 8, the depression force applied to the brake pedal 15 , The depression stroke of the brake pedal 15 or the detected value of the output of the brake valve 16.

In the thirteenth to nineteenth embodiments described above, the case of the TRC cut valves 23 and 24 which are linear solenoid valves has been described. However, the present invention is a TRC cut valve which is composed of the following throttle valves. The cut valves 23 and 24 can also be used.

As shown in FIG. 24, the TRC cut valves 23 and 24 have a main body 25.
An axial hole 26 is formed in the center of the. This hole 2
An annular groove 27 is formed on the inner peripheral surface on one end side of 6, and an inlet side flow passage hole 28 connected to the brake actuators 13 and 14 is formed so as to communicate with the annular groove 27. There is.

The outlet side flow passage hole 29 connected to the brake cylinder of the rear rear wheels 7'and 8'is the axial hole 26 of the main body 25.
Is bored so as to communicate with the other end. Further, the main body 25 is provided with a bypass flow passage hole 30 communicating with one end side of the axial hole 26 and the outlet side flow passage hole 29, and a part of the bypass flow passage hole 30 is reduced in diameter. . The diameter d of the reduced diameter portion of the bypass flow passage hole 30 is set smaller than the diameter D of the inlet side flow passage hole 28. Further, the main body 25 is provided with a return flow passage hole 31 that directly connects the inlet side flow passage hole 28 and the outlet side flow passage hole 29. The check valve 3 for allowing only the flow of the brake fluid from the outlet side passage hole 29 toward the inlet side passage hole 28 is provided in the return passage hole 31.
2 are provided.

A valve element 33 is provided in the axial hole 26 of the main body 25.
Is slidably inserted, and the valve body 33 is provided with a flow passage hole 34 having a T-shaped cross section, which is composed of a radial hole and an axial hole. The diameter of the flow passage hole 34 is set to be the same as the diameter D of the inlet side flow passage hole 28.

Further, a spring 35 for constantly urging the valve element 33 toward one end of the hole 26 (leftward in FIG. 2).
Is contracted in the hole 26, and the valve body 33 is energized when energized.
A solenoid 36 for attracting the magnet to the other end (to the right in FIG. 2) against the biasing force of the spring 35 is arranged so as to surround the outer periphery of the hole 26 on the other end side. This valve body 3
3 contacts the plug 37 that closes one end of the hole 26, so that its movement to the left is blocked.

Then, the TRC cut valves 23, 2
4, the solenoid 36 is not energized under normal conditions, and therefore the valve element 33 is in the position shown in the figure in which it contacts the plug 37 by the urging force of the spring 35. Disc 3
In this position of 3, the radial hole of the flow path hole 34 of the valve element 33 is aligned with the annular groove 27, so that the inlet side flow path hole 28 is formed.
Communicates with the outlet side flow passage hole 29 through the annular groove 27, the flow passage hole 34 of the valve element 26, and the axial hole 26, and the TRC cut valves 23, 24 are in an open state. At this time,
The bypass passage hole 30 is closed by the valve element 33.

Therefore, during normal braking, the brake pressure generated by the brake actuators 13 and 14 is supplied to the brake cylinders of the front and rear wheels 7 and 8 so that the brakes of the front and rear wheels 7 and 8 are actuated and the inlet side flow passage hole is formed. 28, the annular groove 27, the flow passage hole 34 of the valve element 26, the axial hole 26, and the outlet side flow passage hole 2 without being throttled at all, and can be applied to the brake cylinders of the rear rear wheels 7'and 8 '. It is supplied and the brakes of the rear rear wheels 7 ', 8'also operate. In that case, the pressure increasing speeds of the rear rear wheels 7 ', 8'which are driven wheels are the same as the pressure increasing speeds of the front and rear wheels 7, 8 which are driving wheels.

At the time of TRC, a current having a relatively small set value is supplied from the ABS / TRCECU 22 to the solenoid 36. Due to this energization of the solenoid 36, the valve element 33 is attracted and moves to the right by a predetermined amount against the urging force of the spring 35 to the position shown in FIG. At this position of the valve body 33, the annular groove 27 and the bypass flow passage hole 30 are closed by the valve body 33, respectively, and the TRC cut valve 2
3, 24 are closed. Therefore, the inlet side flow passage hole 2
8 is blocked from the outlet side flow passage hole 29, and the flow of the brake fluid from the inlet side flow passage hole 28 to the outlet side flow passage hole 29 is blocked. The flow of the brake fluid from the outlet side flow passage hole 29 to the inlet side flow passage hole 28 is controlled by the check valve 32 and the return flow passage hole 31.
Not blocked by.

At the time of ABS, a relatively large set value current is supplied from the ABS / TRCECU 22 to the solenoid 36. Due to this energization of the solenoid 36, the valve element 33 is attracted and moves further to the right against the urging force of the spring 35 to the position shown in FIG. At this position of the valve element 33, both the annular groove 27 and the bypass passage hole 30 are opened. As a result, the inlet-side flow passage hole 28 includes the annular groove 27, the axial hole 26, and the bypass flow passage hole 30.
The TRC cut valves 23 and 24 are in a throttle open state by communicating with the outlet side flow path hole 29 via the. Therefore, the brake fluid that has flowed into the inlet-side flow passage hole 28 is
The brake pressure of the brake cylinders of the rear rear wheels 7'and 8'is increased through the axial hole 26, the bypass flow passage hole 30, and the outlet side flow passage hole 29. At this time, because the flow of the brake fluid is restricted by the reduced diameter portion of the bypass flow passage hole 30,
The pressure increasing speeds of the rear rear wheels 7'and 8'which are driven wheels are lower than the pressure increasing speeds of the front and rear wheels 7 and 8 which are driving wheels.

Therefore, this TRC cut valve 2
In Nos. 3 and 24, the set solenoid current C is set to the above-mentioned relatively large set value during the ABS pressure increasing control, so that the speed of increasing the brake pressure on the driven wheel side is increased. It can be smaller than the pressure velocity.

In each of the above-described embodiments, the case where the present invention is applied to the air over hydraulic brake control system shown in FIG. 27 has been described.
The rear shaft is composed of at least a drive shaft and a driven shaft, and a TR is connected to a brake circuit that connects the brake of the drive wheel supported by the drive shaft and the brake of the driven wheel supported by the driven shaft.
It goes without saying that the brake control system can be applied to any brake control system as long as it is provided with the C-cut valves 23 and 24.

[0101]

As is apparent from the above description, according to the anti-skid brake control system of the present invention, the AB
By controlling the duty of the TRC cut valve including the electromagnetic on-off valve or controlling the solenoid current that determines the throttle amount of the TRC cut valve including the electromagnetic variable throttle valve during the brake pressure increase control in S, Since the pressure increase rate of the brake pressure on the driving wheel side is set to be lower than the pressure increase rate of the brake pressure on the drive wheel, it is possible to make it difficult to lock the driven wheel, which has been apt to be locked conventionally.
As a result, it is possible to prevent the driven wheels from being locked early during the ABS pressure increase control.

Further, according to the present invention, when the brake pressure increase control in the ABS is performed, the TRC cut valve is arranged so that the start of increasing the brake pressure of the driven wheels is delayed by a set time from the start of increasing the brake pressure of the drive wheels. Is controlled to delay the braking of the driven wheels, it is possible to similarly lock the driven wheels. As a result, similarly, it is possible to prevent early locking of the driven wheels during the ABS pressure increase control.

Further, according to the present invention, the duty ratio in the duty control of the TRC cut valve, the solenoid current for determining the throttle amount, or the set time of the delay of the start of increasing the brake pressure on the driven wheel side is set in the duty control of the modulator. It is calculated from the modulator duty ratio, road surface μ, wheel speed of driven wheels, load of driven wheels, load of driven wheels, pedal force of brake pedal, stroke of brake pedal, or output of brake valve. It can be controlled according to the actual situation of the driving wheel. Therefore, it is possible to perform more appropriately and finely the increase control of the brake pressure on the driven wheel side during the ABS pressure increase control, and it is possible to prevent the early locking of the driven wheel more accurately during the ABS pressure increase control.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a first embodiment of an anti-skid brake control method of the present invention.

FIG. 2 is a diagram showing a flow of processing in the first embodiment.

FIG. 3 is a diagram illustrating a second embodiment of the present invention.

FIG. 4 is a diagram showing a flow of processing in a second embodiment.

FIG. 5 is a diagram showing a flow of processing in a third embodiment of the present invention.

FIG. 6 is a diagram illustrating a fourth embodiment of the present invention.

FIG. 7 is a diagram illustrating a fifth embodiment of the present invention.

FIG. 8 is a diagram showing a flow of processing in fourth and fifth embodiments.

FIG. 9 is a diagram showing a flow of processing of ABS pressure reduction control in the fourth and fifth embodiments.

FIG. 10 is a diagram showing a flow of processing in a sixth embodiment of the present invention.

FIG. 11 is a diagram showing a flow of processing in a seventh embodiment of the present invention.

FIG. 12 is a diagram showing a flow of processing in an eighth embodiment of the present invention.

FIG. 13 is a diagram showing a flow of processing in a ninth embodiment of the present invention.

FIG. 14 is a diagram showing a flow of processing in a tenth embodiment of the present invention.

FIG. 15 is a diagram showing a processing flow in an eleventh embodiment of the present invention.

FIG. 16 is a diagram showing a flow of processing in a twelfth embodiment of the present invention.

FIG. 17 is a diagram showing a flow of processing in a thirteenth embodiment of the present invention.

FIG. 18 is a diagram showing a flow of processing in a fourteenth embodiment of the present invention.

FIG. 19 is a diagram showing a flow of processing in a fifteenth embodiment of the present invention.

FIG. 20 is a drawing showing the flow of processing in a sixteenth embodiment of the present invention.

FIG. 21 is a diagram showing a flow of processing in a seventeenth embodiment of the present invention.

FIG. 22 is a drawing showing the flow of processing in an eighteenth embodiment of the present invention.

FIG. 23 is a diagram showing a flow of processing in a nineteenth embodiment of the present invention.

FIG. 24 is a view showing a modified example of the TRC cut valve and showing a normal state.

25 is a diagram showing a closed state of the TRC cut valve shown in FIG. 24 during TRC.

FIG. 26 is a diagram showing an open state of the TRC cut valve shown in FIG. 24.

FIG. 27 is a circuit diagram showing an example of a conventional brake control system including a TRC cut valve between a drive wheel brake and a driven wheel side brake in a multi-axle vehicle.

[Explanation of symbols]

1 ... left front wheel, 2 ... right front wheel, 3 ... left front wheel speed sensor,
4 ... Wheel speed sensor for front right wheel, 5 ... ABS modulator for front wheel, 6 ... Brake actuator for front wheel, 7 ... Left front wheel (driving wheel), 8 ... Front front wheel (driving wheel), 7 '... Left rear wheel (Driven wheel), 8 ′ ... Rear rear wheel (driven wheel), 9 ... Wheel speed sensor for left front and rear wheels, 10 ... Wheel speed sensor for right front and rear wheels, 9
'... left rear wheel wheel speed sensor, 10' ... right rear rear wheel speed sensor, 11 ... left rear wheel ABS modulator, 12
... ABS modulator on the right rear wheel side, 13 ... Brake actuator on the left rear wheel side, 14 ... Brake actuator on the right rear wheel side, 15 ... Brake pedal, 16 ... Brake valve, 17,17 '... Air tank, 18, 19 ... TRC valve, 22 ... ABS / TRC ECU, 22a ... TRC
Cut valve control means, 22b ... Road surface μ calculation means, 22
c ... Wheel speed difference calculating means, 22d ... Solenoid current setting means, 23 ... Left rear wheel side TRC cut valve, 24 ... Right rear wheel side TRC cut valve, 25 ... Main body, 26 ... Axial hole, 27 ... Annular groove, 28 ... inlet side passage hole, 29 ... outlet side passage hole, 30 ... bypass passage hole, 31 ... return passage hole,
32 ... Check valve, 33 ... Valve body, 34 ... Flow path hole, 35 ... Spring, 36 ... Solenoid, 37 ... Plug, 38, 39
... load detector on drive wheel side, 38 ', 39' ... load detector on driven wheel side, 40 ... pedal force meter, 41 ... stroke sensor,
42 ... Pressure sensor, μ ... Friction coefficient, t1 ... Set time for delaying start of boosting pressure on driven wheel side, A ... Constant for duty ratio, C ... Solenoid current, V _a ... Wheel speed of driven wheel,
V _b ... Wheel speed of driving wheels

Claims (9)

[Claims] 1. A brake cylinder for a drive wheel, a brake cylinder for a driven wheel, and a common brake actuator for applying a brake pressure to both brake cylinders at the time of braking to brake both the drive wheel and the driven wheel. , An ABS modulator that supplies a working fluid to the brake actuator during braking, and an ABS modulator that adjusts the pressure of the supplied working fluid during anti-skid brake control (hereinafter, referred to as ABS); and an ABS modulator that operates by depressing the brake pedal during braking. A brake valve that supplies working fluid to the brake actuator through the ABS modulator and discharges the working fluid of the brake actuator through the ABS modulator when the brake pedal is released when the brake is released. A TRC valve that supplies a working fluid to the brake actuator at the time of a trawl (hereinafter, referred to as TRC) communicates with the brake cylinder of the driven wheel and the brake actuator during normal operation, and at the time of TRC, the brake cylinder of the driven wheel and A TRC cut valve for shutting off the brake actuator, and an ABS for adjusting the pressure of the working fluid supplied to the brake actuator so as to eliminate the lock tendency when the lock tendency of at least the driving wheel is detected during braking. The ABS modulator is controlled so as to perform the TR, and when the idling tendency of the driving wheels is detected, the TR is controlled so that the working fluid is supplied to the brake actuator so as to eliminate the tendency.
An anti-skid brake control system comprising: an electronic control device that controls a C valve and operates the TRC cut valve that shuts off a brake cylinder of the driven wheel and the brake actuator, wherein the electronic control device is operated during ABS. An anti-skid brake control system comprising: TRC cut valve control means for actuating and controlling the TRC cut valve in order to adjust the brake pressure of the brake cylinder of the driven wheel. 2. The TRC cut valve is connected to the brake cylinder of the driven wheel and the brake actuator when the valve is off, and has two states of on / off for disconnecting the brake cylinder and the brake actuator of the driven wheel when the valve is turned on. The TRC cut valve control means is a control means for controlling ON / OFF of the TRC cut valve by duty control during ABS pressure increase control of the ABS modulator. The anti-skid brake control system according to claim 1. 3. The TRC cut valve control means turns on and closes the TRC cut valve when pressure increase control of the ABS modulator is started, and the TRC cut valve control means
After the set time has passed after the RC cut valve is turned on, the T
The anti-skid brake control system according to claim 2, wherein the anti-skid brake control system is control means for performing duty control of the RC cut valve. 4. The electronic control unit further comprises road surface μ calculating means for calculating a road surface friction coefficient (hereinafter referred to as road surface μ), and the TRC cut valve control means comprises the TRC based on the road surface μ. The anti-skid brake control system according to claim 2 or 3, which is a control unit that calculates the duty ratio of the cut valve. 5. The TRC cut valve control means includes a wheel speed of the driven wheel, a load of the driven wheel, a load of the driving wheel, a pedaling force of the brake pedal, a stepping stroke of the brake pedal, and a brake pedal. 4. The anti-skid brake control system according to claim 2, wherein the anti-skid brake control system is control means for calculating the duty ratio of the TRC cut valve based on any one of the outputs. 6. The TRC cut valve is set to a communication state in which the brake cylinder of the driven wheel and the brake actuator are communicated when the TRC cut valve is off, and the TRC cut valve of the driven wheel is set according to the magnitude of the solenoid current supplied to the solenoid. The electronic control unit is composed of an electromagnetic variable throttle valve in which a throttle state that throttles the communication between the brake cylinder and the brake actuator and a shut-off state that shuts off the brake cylinder of the driven wheel and the brake actuator are set. The solenoid current setting means for presetting the solenoid current so that the throttle amount of the electromagnetic variable throttle valve becomes a desired amount is provided, and the TRC cut valve control means is controlled by the solenoid current setting means during the ABS modulator pressure increasing control. The TR is set by the preset solenoid current set in advance. The anti-skid brake control system according to claim 1, which is a control means for controlling the C-cut valve. 7. The TRC cut valve control means closes the TRC cut valve when pressure increase control of the ABS modulator is started, and turns on the TRC cut valve by the set solenoid current to turn on the set solenoid current. Control means for opening the throttle amount corresponding to the above, and the solenoid current setting means is for the TR
The anti-skid brake control system according to claim 6, wherein the anti-skid brake control system is a control unit that sets the set solenoid current after a set time has elapsed after the C-cut valve is closed. 8. The electronic control device further comprises a road surface μ calculating means for calculating a road surface friction coefficient (hereinafter referred to as road surface μ), and the solenoid current setting means uses the road surface μ to set the solenoid. The anti-skid brake control system according to claim 6 or 7, which is a control means for setting a current. 9. The solenoid current setting means includes a wheel speed of the driven wheel, a load of the driven wheel, a load of the driving wheel,
The control means for setting the solenoid current based on any one of the depression force of the brake pedal, the depression stroke of the brake pedal, and the output of the brake valve. Skid brake control system.