JPH07251730A - Traction control device - Google Patents

Abstract

PURPOSE:To prevent residual pressure in non drive wheel brake cylinder at TRC by entering a cut valve by a TRC cut valve control means after canceling holding of a brake actuation holding means when traction control(TRC) is started. CONSTITUTION:When control of TRC is started, brake actuation holding means (HSC valve) 20, 21 are previously made OFF and then TRC cut valves 35, 36 are entered. That is, the HSA valves 20 and 21 are made OFF by the HSA ECU 32 when they are not OFF according to a HSA valve control signal from the HSA ECU 32 in a HSA valve priority control means 22a. And the TRC cut valves 35, 36 are ON and closed by the ABS/TRC ECU 22 and then TRC ECU 22 are made ON to start TRC control. Thus, any residual pressure may not be produced in a brake cylinder of rear wheels 7', 8' as TRC cut valves 35 and 36 are ON after The HSA valves 20 and 21 are OFF.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traction control (hereinafter referred to as TRC) which prevents the drive wheels from slipping by operating a brake of the drive wheels when the drive wheels tend to slip at the time of starting or sudden acceleration. (Also referred to as) system.

[0002]

2. Description of the Related Art In recent years, in automobiles, the power loss of the engine is minimized when the driving wheels tend to slip, and the driving force of the driving wheels is more effectively transmitted to the road surface to effectively propel the vehicle. In order to achieve this, a TRC system that adjusts the driving force of driving wheels has been developed.

On the other hand, in automobiles, it is possible to easily start up a hill, and to step on the brake pedal in a traffic light or in a traffic jam, without the need for a sudden change operation from the parking brake or the brake pedal to the accelerator pedal. Hill start assist device (Hill Start) to reduce the fatigue caused by the brake operation by making continuous operation unnecessary
Aid: hereinafter also referred to as HSA) has been developed.

Conventionally, as an example of a brake control system provided with an HSA and a TRC system, there is a brake control system as shown in FIG. 6, for example. This brake control system brakes in order to prevent locking of braking wheels during braking. Anti-skid brake control (hereinafter also referred to as ABS) system for adjusting force, TRC and HS
This is a system in which A is integrated.

As shown in FIG. 6, in the brake control system, the front wheel side has one shaft and the rear wheel side has two shafts, the first shaft and the third shaft are non-driving shafts, and the second shaft is a driving shaft. It is applied to triaxial vehicles. This brake control system controls wheel speed sensors 3 and 4 that detect wheel speeds of left and right front wheels 1 and 2 that are non-driving wheels, an ABS modulator 5 that adjusts brake pressure of the front wheels 1 and 2, and front wheels 1 and 2. A brake actuator 6 that generates power, wheel speed sensors 9 and 10 that detect wheel speeds of left and right front and rear wheels 7 and 8 that are drive wheels, front and rear wheels 7 and 8, and left and right rear rear wheels 7 ′ that are non-drive wheels. ABS modulators 11 and 12 for adjusting the brake pressures of the left and right wheels respectively, brake actuators 13 and 14 for generating braking forces to the front and rear wheels 7 and 8 and the rear rear wheels 7'and 8 ', Dual brake valve 16, TR controlled to open and close by the brake pedal 15
A traction control valve (hereinafter referred to as TRC) which is a solenoid valve that opens at C to send the compressed air in the air tank 17 to the ABS modulators 11 and 12 of the left and right front and rear wheels 7 and 8 and rear rear wheels 7'and 8 ', respectively. (Also referred to as valves) 18,19, the brake pipes connected to the brake actuators 13,14 are provided in a portion between the brakes of the front and rear wheels 7,8 and the brakes of the rear rear wheels 7 ', 8', and T
Provided on the downstream side of the traction control cut valves (hereinafter also referred to as TRC cut valves) 35, 36 and the dual brake valve 16 that operate at RC time to shut off the brakes of the rear rear wheels 7 ', 8'from the brake actuators 13, 14. At this time, the compressed air in the air tanks 17 and 17 'is supplied to the front wheel ABS modulator 5 and the rear wheel ABS modulators 11 and 12, respectively, and shuts off.
Also called A valve) 20, 21, each wheel speed sensor 3, 4,
Wheel speed signals are supplied from 9 and 10, and each AB
S modulators 5, 11, 12 and TRC valves 18, 1
9 and A for controlling each TRC cut valve 35, 36
BS / TRC control unit (hereinafter ABS / T
RC ECU) 22 and a clutch stroke sensor 23, a clutch stroke signal, a clutch switch 24, a clutch hydraulic pressure signal, a neutral switch 25, a neutral signal, a stop lamp switch 26, a stop lamp signal, and a parking brake switch 27. The parking brake signal, the door opening / closing signal from the door switch 28, and the HSA operating signal from the HSA operating switch 29 are supplied, respectively, and the pilot lamp 30 and the HSA valves 20, 21 are supplied.
And an HSA control unit 32 for controlling the buzzer 31.

In the brake control system configured as described above, TRC is performed by the brake control for the front and rear wheels 7 and 8 which are the driving wheels, and the TRC by this brake control is performed as follows. That is, the ABS /
The TRC ECU 22 calculates based on the wheel speed signals from the wheel speed sensors 3, 4, 9 and 10, and if it determines that the front and rear wheels 7 and 8 that are driving wheels are in a slip tendency based on the calculation result, the ABS / The TRC ECU 22 outputs control signals to the modulators 11 and 12, the TRC valves 18 and 19 and the TRC cut valves 35 and 36 corresponding to the front and rear wheels 7 and 8 and the rear rear wheels 7'and 8'which tend to slip.

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 35 and 36.
Therefore, compressed air from the air tank 17 is supplied to the brake actuators 13 and 14 through the TRC valves 18 and 19, the double check valves 33 and 34, and the ABS modulators 11 and 12, whereby the brake actuators 13 and 14 operate and the brake pressure is increased. To occur. The brake pressure generated by the brake actuators 13 and 14 is supplied only to the brake cylinders (not shown) of the front and rear wheels 7 and 8 that tend to slip, and
Is braked. By the braking of the front and rear wheels 7 and 8, the rotational driving force of the front and rear wheels 7 and 8 which are the driving wheels is suppressed, and as a result, the slip tendency of the front and rear wheels 7 and 8 which tends 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. Also,
Since the TRC cut valves 35, 36 are closed, the brake pressure generated in the brake actuators 13, 14 is not supplied to the brake cylinders (not shown) of the rear rear wheels 7 ', 8'which are non-driving wheels, and the rear rear The wheels 7 ', 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 '.

The HSA operates as follows.
First, the HSA operation switch 29 is turned on and the parking brake is released. The release of the parking brake is detected by the parking brake switch 27, and the parking brake release signal is sent to the HSA ECU 32.
Sent to. Next, when the brake pedal 15 is depressed, a brake operation signal is supplied from the stop lamp switch 26 to the HSA ECU 32. Air is supplied to the brake actuator 6 from the dual brake valve 16 and is supplied to the brake actuators 13 and 14 through the double check valves 33 and 34.
The brake works. When the brake pedal 15 is continuously depressed for a predetermined time (eg, 1 second) or more, the HSA ECU
32 turns on the HSA valves 20 and 21. As a result, the solenoid valve is actuated to disconnect the brake valve 16 and the brake actuators 6, 13, 14 from each other, and as a result, the brake actuators 6, 13, 14 are held at a pressure corresponding to the output of the brake valve 16. It At the same time when the HSA valves 20 and 21 are turned on, the HSA ECU 32 turns on the pilot lamp 30 to notify the driver of the HSA valves 20,
Notify that 21 is turned on. The driver is the pilot lamp 30
The brake pedal 15 is released when the light is illuminated, but the brake is maintained in the activated state. Further, in this state, the brake is maintained in the operating state regardless of whether the gear is in neutral or the clutch is released.

To turn off the HSA valves 20 and 21, (1) turn off the HSA operating switch 29, or (2) turn off the neutral switch 25 by gear-in and turn off the clutch switch 24 by connecting the clutch. Alternatively, either the clutch stroke sensor 23 is turned off by the half clutch, or (3) the parking brake is operated and the parking brake switch 27 is turned on. By these operations, the HSA valves 20 and 21 are turned off. When the HSA valves 20 and 21 are turned off, the brake actuators 6, 13, 1
The air supplied to the ABS 4 is the ABS modulator 5,
After passing through 11, 12 and HSA valves 20 and 21, it is discharged from the brake valve 16 and the brake is released. In the case of (2), it is carried out at the time of starting, and it is particularly effective when starting on a slope. Further, in the case of (3), the parking brake is surely applied.

Further, when the door switch 28 is turned on while the HSA valves 20 and 21 are turned on, that is, when the door is opened, the HSA ECU 32 causes the buzzer 31 to operate.
Sounds to sound an alarm. This is H
This is to prevent the SA valves 20 and 21 from being used as parking brakes.

[0011] With such an HSA, it becomes possible to easily start on a slope without any need for a sudden change operation from the parking brake or the brake pedal to the accelerator pedal. It is not necessary to continue stepping on the brake pedal, and fatigue from braking can be reduced.

As is clear from the operation of the TRC and HSA, the TRC and HSA are controlled independently of each other. The ABS in the above-mentioned brake control system is not directly related to the present invention, and therefore its explanation is omitted.

ABS / TR not equipped with HSA
The C system has also been conventionally developed. AB like this
As an example of the S / TRC system, there is a system as shown in FIG. 7, for example. The same components as those of the brake control system shown in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 7, reference numeral 37 is an air tank 17 for storing compressed air for braking for TRC, 38 is an engine, 39 is a governor for operating a governor link of a mechanical governor for changing and setting the lower limit of the rotational speed of the engine 38. An actuator, 40 is an accelerator pedal, 41 is a battery power source, 42 is a safety relay, 43 is a traction control pilot lamp, and 44 is a brake pressure switch.

In this ABS / TRC system,
TRC by brake control and TRC by engine control
And are to be done. In that case, the TRC by the brake control is almost the same as the TRC in the brake control system shown in FIG. 6 described above, and the description thereof will be omitted. However, in the ABS / TRC system shown in FIG. 7, ON / OFF of the TRC cut valves 35 and 36 is TR.
This is performed by the air pressure signal which is the output pressure of the C valves 18 and 19.

TRC under engine control is performed as follows. That is, ABS / TRC EC
When the U22 detects that the front and rear wheels 7, 8 are slipping and outputs a control signal to the governor actuator 39, the governor actuator 39 is rotated by this control signal to control the deceleration of the engine 38. Due to the deceleration of the engine 38, 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 is eliminated. At this time, TRC by brake control
Therefore, the lower limit of the rotation speed of the engine 38 is adjusted to a slightly larger lower limit so that the engine is not stalled due to the braking force acting on the front and rear wheels 7, 8.

In this ABS / TRC system,
When the ABS / TRC ECU 22 is performing the TRC, the traction pilot lamp 43 is turned on to inform the driver that the TRC is being performed.

[0018]

However, in the conventional brake control system in which ABS, TRC, and HSA shown in FIG. 6 are integrally incorporated, and TRC and HSA are controlled independently of each other, When the TRC is activated immediately after starting from the state in which the brakes are operating, the brake pressure generated by the brake actuators 13 and 14 by the HSA is the rear rear wheel that is the non-driving shaft of the third shaft as shown in FIG. Before being completely discharged from the 7'and 8'brake cylinders, the TRC cut valve 3
Since 5, 36 are closed, there is a problem that residual brake pressure may occur in the brake cylinders of the rear rear wheels 7 ', 8'.

Further, in the brake control system equipped with the ABS / TRC system shown in FIG. 7, when the vehicle starts after the vehicle is stopped by a brake on a slope or the like, the pedal is changed from the brake pedal 15 to the accelerator pedal 40. If done quickly, the TRC may be activated immediately. Also in such a case, as shown in FIG. 9, similarly, the brake pressure generated in the brake actuators 13, 14 by depressing the brake pedal 15 causes the rear rear wheels 7 ', 8'which are non-driving shafts of the third shaft. Before it is completely discharged from the brake cylinder, TRC cut valves 35, 36
Is closed, there arises a problem that residual brake pressure may occur in the brake cylinders of the rear rear wheels 7 ', 8'.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a TRC cut valve even when the TRC is actuated immediately when the vehicle starts after the vehicle is stopped due to brake operation. It is an object of the present invention to provide a traction control system capable of reliably preventing residual pressure from being generated in a brake cylinder of a non-driving wheel to which brake pressure is supplied via.

[0021]

In order to solve the above-mentioned problems, the invention of claim 1 is a wheel speed sensor for detecting a wheel speed of a predetermined number of non-driving wheels and a wheel speed of a predetermined number of driving wheels. A pressure source for supplying a pressure fluid for operating a brake of each wheel, at least one non-drive wheel brake of the non-drive wheel and at least one drive of the drive wheel operated by the supply of the pressure fluid. A brake actuator that operates the wheel brakes in common, a manual brake valve that is disposed between the brake actuator and the pressure source to control the supply and discharge of pressure fluid to and from the brake actuator, and a brake valve that is separate from the brake valve. A traction control valve for controlling the supply and discharge of pressure fluid from the pressure source to the brake actuator; Is disposed in the brake fluid passage between the over key actuator and said one non-driven wheel brake,
A normally open traction control cut valve that shuts off the brake fluid passage during traction control, and determines whether a slip tendency has occurred in the drive wheels by a predetermined method based on the wheel speeds. In the traction control system characterized by comprising a traction control electronic control device for turning on the traction control valve and turning on the traction control cut valve when it is determined that a slip tendency occurs in A drive wheel brake and a brake operation holding means for holding the drive wheel brake in an operating state when necessary, and a traction control electronic control device provided in the traction control electronic control unit, when starting traction control,
A traction control cut valve control means for outputting a control signal for turning on the traction control cut valve after the brake operation holding means releases the brake operation state.

According to a second aspect of the present invention, the brake operation holding means is constituted and is disposed in a fluid passage between the brake valve and the brake actuator, and is normally open to control disconnection of the fluid passage. A hill start auxiliary operation valve, a hill start auxiliary operation switch for outputting a hill start auxiliary signal, operation control member operation detecting means for detecting an operation state of the operation control member of the vehicle and outputting an operation control member operation signal, Based on the slope start assisting signal from the slope start assisting switch and the operation control member operation signal from the operation control member operation detecting means, it is determined whether or not the slope start assisting operation condition is satisfied, and the slope start assisting operation is performed. When it is determined that the conditions are met, the slope starting assist operation valve is turned on, and the slope starting assist signal and the operation control member are set. Based on the work signal, it is determined whether or not there is a condition for canceling the operation for starting the slope start, and when it is judged that the condition for canceling the start assist for the slope is turned off, the electronic control device for starting the slope start is turned off. When,
When the traction control cut valve control means is configured to start traction control, when the slope start auxiliary operation valve is on, the slope start auxiliary operation valve is turned off first, and then the traction control cut valve is turned on. It is characterized in that it is provided with a slope start assist actuation valve priority control means for outputting a control signal.

Further, in the invention of claim 3, the slope starting auxiliary operation valve priority control means is a control means for turning on the traction control cut valve after a predetermined time has elapsed after turning off the slope starting auxiliary operation valve. Is characterized by.

Further, in the invention of claim 4, the brake operation holding means is a brake pedal for controlling the operation of the brake valve, and the traction control cut valve control means releases a predetermined time after the brake pedal is released. It is a control means for turning on the traction control cut valve.

[0025]

According to the invention of claim 1 having such a configuration, when the traction control is started, the traction control cut valve control means
The traction control cut valve is turned on after the holding of the operating states of the non-driving wheel brake and the driving wheel brake by the brake operation holding means is released. Therefore, the non-driving wheel brake cylinder is disconnected after the operation of the non-driving wheel brake is released. Therefore, no residual brake pressure is generated in the non-drive wheel brake cylinder during traction control.

According to the second aspect of the invention, when the TRC is started immediately after the vehicle is started by the slope start assist device, the slope start assist operation valve priority control means in the traction control electronic control unit starts the slope start. After the auxiliary actuating valve is opened first, the traction control cut valve comes to close. Therefore,
When the traction control cut valve is closed, the brake pressure in the non-driving wheel brake cylinder due to the operation of the slope start assist device is discharged.
In this way, no residual brake pressure is generated in the non-drive wheel brake cylinder during traction control.

In particular, according to the third aspect of the invention, the traction control cut valve is closed after a predetermined time has elapsed after the slope start assisting operation valve was opened first. Therefore, when the traction control cut valve is closed, the brake pressure in the non-drive wheel brake cylinder is completely discharged. In this way, the residual pressure of the brake pressure in the non-driving wheel brake cylinder can be more reliably prevented during traction control.

Further, in the invention of claim 4, the traction control cut valve is closed after a predetermined time has elapsed after the brake pedal was released. Therefore, similarly, when the traction control cut valve is closed, the brake pressure in the non-drive wheel brake cylinder is completely discharged, and the residual pressure in the non-drive wheel brake cylinder is more surely prevented.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a brake control system to which an embodiment of a traction control system including a slope starting device according to the present invention is applied. The same components as those of the brake control system shown in FIG. 6 described above are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 1, in this embodiment, the ABS / TRC ECU 22 shown in FIG. 6 is provided with the HSA valves 20, 2 at the time of starting the TRC control immediately after starting by the HSA operation.
The HSA valve priority control means 22a for outputting a control signal for turning on the TRC cut valves 35 and 36 after first turning off 1 is provided, and the ABS / TRC ECU
HSA valve priority control means 22a in 22 and HSA E
The CU 32 is electrically connected so that signals can be exchanged between the HSA valve priority control means 22 a and the HSA ECU 32.

In this embodiment, when the TRC control is started, the HSA valves 20 and 21 are first turned off,
After that, the TRC cut valves 35 and 36 are turned on. That is, as shown in FIG. 2, when the control of the TRC is started in step S1, the HSA valve priority control means 22a determines whether the HSA valves 20 and 21 are off based on the HSA valve control signal from the HSA ECU 32 in step S2. Determine whether or not. When the HSA valve priority control means 22a determines that the HSA valves 20 and 21 are not off, the HSA valve priority control means 22a determines that the HSA valves are not turned off in step S3.
The HSA valves 20 and 21 are turned off by the ECU 32. As a result, the brake pressure of each wheel generated by the HSA operation is discharged.

Then, in step S4, the HSA is
Based on the control signal for turning off the HSA valve from the ECU 32, the ABS / TRC ECU 22 turns on and closes the TRC cut valves 35 and 36, and then in step S5, the ABS / TRC ECU 22 causes the ABS / TRC ECU 22 to turn on the TRC valves 18 and 19.
Is turned on to start TRC control. H in step S2
When it is determined that the SA valves 20 and 21 are off, the process proceeds to step 4 and the processes after step 4 are performed.

The operation of the TRC cut valves 35 and 36 in step S4 and the TRC in step S5 are performed.
It can also be performed simultaneously with the operation of the valves 18 and 19. As described above, in this embodiment, when the TRC control is started, the HSA valves 20 and 21 are first turned off, and then the TRC cut valves 35 and 36 are turned on, so that the rear rear wheels 7'and 8'are prevented. Almost no residual pressure is created in the brake cylinder.

FIG. 3 is a diagram showing a control flow of another embodiment of the present invention. In this embodiment, when the TRC control is started, the HSA valves 20 and 21 are first turned off, and the rear rear wheels 7 ',
After the time in which the residual brake pressure in the 8'brake cylinder becomes zero, the TRC cut valves 35, 3
6 is turned on.

That is, as shown in FIG. 3, the TRC control is started in step S1 and the HSA valves 20, 21 in step S2 as in the embodiment shown in FIG.
Is turned off and the HSA valves 20 and 21 are turned off in step S3.
Before the process of turning on the TRC cut valves 35 and 36 of No. 4 is performed in step S6, the HSA valves 20 and 21 are
It is determined whether the elapsed time after turning off exceeds a predetermined time. When it is determined that the elapsed time after the HSA valves 20 and 21 are turned off exceeds the predetermined time, the processes from step S4 are performed as described above. If it is determined in step 6 that the elapsed time after turning off the HSA valves 20 and 21 does not exceed the predetermined time, the process of step S6 is repeated until the elapsed time exceeds the predetermined time. Also, step S2
When it is determined that the HSA valves 20 and 21 are off in step S6, the process proceeds to step S6, and the processes after step S6 are performed.

As described above, in this embodiment, after a predetermined time has elapsed after the HSA valves 20 and 21 were turned off, the TRC
Since the cut valves 35 and 36 are turned on, the rear rear wheels 7 ',
The residual pressure of the brake pressure in the 8'brake cylinder can be more reliably reduced to zero.

In this embodiment, ABS / TR
Although the C ECU 22 and the HSA ECU 32 are separately configured, the present invention is not limited to the ABS as shown in FIG.
The / TRC ECU 22 and the HSA ECU 32 may be integrally configured.

FIG. 5 is a diagram showing a control flow of still another embodiment of the present invention. In this embodiment, as shown in FIG.
An ABS / TRC system without SA valves 20 and 21 is used. Further, in this embodiment, the TRC under the brake control does not operate within a fixed time T ₁ after the brake operation is released. That is, ABS
The / TRC ECU 22 starts measuring time when there is no pedal depression signal from the brake pedal 15, that is, when a brake signal edge is detected. In this state, ABS /
The TRC ECU 22 does not turn on the TRC valves 18 and 19 if the measured time is less than a certain time even if the front and rear wheels 7 and 8 that are the driving wheels are detected to slip. As a result, TRC will be
Even under the operating condition, the TRC by the brake control is not started, and therefore the TRC cut valves 35 and 36 are not closed.

The control of this embodiment will be specifically described.
As shown in FIG. 5, first, when the brake signal edge, that is, the brake release due to the release of the brake pedal 15 is detected in step S1, the timer is counted. Next, in step S2, it is determined that the wheels are slipping, and if it is determined that the wheels are not slipping, the process directly returns to the start. If it is determined in step S2 that the wheels are slipping, then TRC under engine control is started in step S3.

Next, in step S4, it is judged whether or not the TRC under the brake control is necessary. If it is judged that the TRC under the brake control is not necessary, the process directly returns to the start. If it is determined in step S4 that TRC by brake control is necessary, it is determined in step S5 whether or not time T ₁ seconds has elapsed after the brake signal edge, and it is determined that time T ₁ seconds has not elapsed. When it is done, it returns to the start as it is. As a result, even if the front and rear wheels 7 and 8 of the driving wheels are in the TRC start condition, the predetermined time T ₁ has not elapsed after the brake is released, and therefore the TRC by the brake control is not performed. Therefore, TRC
The cut valves 35, 36 also do not turn on, and the brake passages for the rear rear wheels 7 ', 8'which are non-driving wheels are not blocked. Therefore, the brake pressure of the rear rear wheels 7 ', 8'is exhausted without residual pressure. When it is determined in step S5 that the time T ₁ seconds has elapsed, TRC by brake control is started in step S6.

As described above, in this embodiment, for example, when the brake pedal 15 is released and the accelerator pedal 40 is depressed in order to start the vehicle after the brake is stopped on a slope or the like, the front and rear wheels, which are the driving wheels, are released. Even if 7 and 8 become the TRC start condition, the front and rear wheels 7 and 8 are kept until the predetermined time T ₁ elapses after the release of the brake pedal 15.
TRC by brake control is not performed for the No. 8. Therefore, the TRC cut valves 35 and 36 are not turned on, and the brake pressure of the rear rear wheels 7'and 8'which are non-driving wheels is reliably discharged and no residual pressure is generated.

In this embodiment, the brake control system shown in FIG. 7 is used for explanation. In this brake control system, ON / OFF of the TRC cut valves 35, 36 is controlled by the output pressure of the TRC valves 18, 19. It is controlled by a certain air signal, but TRC cut valve 3
As shown in Fig. 1, ABS / T is turned on and off for 5,36.
It can also be controlled by an electric control signal from the RC ECU 22.

In each of the above-mentioned embodiments, the present invention has been
The description is applied to the brake control system in which the S system and the TRC system are integrally incorporated.
The present invention is not limited to this, and other ABS / TRC can be used as long as TRC is performed by braking.
It can also be applied to a system or a single TRC system.

Furthermore, in the above-mentioned embodiment, the present invention is applied to a three-axis vehicle in which the first and third shafts are non-driving shafts and the second shaft is a driving shaft. Is TR
It can be applied to any vehicle as long as it is a vehicle provided with a C valve and a TRC cut valve.

[0045]

As is apparent from the above description, according to the traction control system of the present invention,
Since the traction control cut valve is turned on after the operating state of the non-driving wheel brake and the driving wheel brake is released, residual pressure in the non-driving wheel brake cylinder can be prevented during traction control.

Further, according to the second aspect of the invention, when the traction control cut valve is closed, the brake pressure in the non-drive wheel brake cylinder is discharged by the operation of the slope start assist device.
After starting from a state where the hill start assist device is operating,
Even when the traction control starts immediately, it is possible to reliably prevent the residual brake pressure from being generated in the non-drive wheel brake cylinder.

Further, according to the third aspect of the present invention, since the brake pressure in the non-driving wheel brake cylinder is completely discharged, the residual pressure of the brake pressure in the non-driving wheel brake cylinder is further improved during traction control. It becomes possible to prevent it more reliably.

Further, according to the invention of claim 4, when the traction control cut valve is similarly closed,
The brake pressure in the non-drive wheel brake cylinder is completely discharged, and the residual pressure in the non-drive wheel brake cylinder can be prevented more reliably.

[Brief description of drawings]

FIG. 1 is a diagram showing a brake control system to which an embodiment of a traction control system including a slope starting device according to the present invention is applied.

FIG. 2 is a diagram showing a flow of control processing of an HSA valve and a TRC cut valve of the embodiment shown in FIG.

FIG. 3 is a diagram showing a flow of control processing similar to FIG. 2, showing another embodiment of the present invention.

FIG. 4 is a diagram showing an electronic control device according to still another embodiment of the present invention.

FIG. 5 is a diagram showing a flow of control processing similar to that of FIG. 2 showing still another embodiment of the present invention.

FIG. 6 is a circuit diagram showing an example of a brake control system in which HSA is integrally incorporated in a conventional ABS / TRC system.

FIG. 7 is a circuit diagram showing an example of a conventional ABS / TRC system.

FIG. 8 is a diagram illustrating a problem of a brake control system in which HSA is integrally incorporated in a conventional ABS / TRC system.

FIG. 9 is a diagram illustrating a problem of a conventional ABS / TRC system.

[Explanation of Codes] 1, 2 ... Left and right front wheels (non-driving wheels) 3, 4.9, 10 ... Wheel speed sensor 5, 11, 12 ... Modulator for anti-skid control, 6, 13, 14 ... Brake actuator,
7, 8 ... left and right front and rear wheels (driving wheels), 7 ', 8' ... left and right rear rear wheels (non-driving wheels), 15 ... brake pedal (brake actuation holding means), 16 ... dual brake valve, 17,
Reference numeral 17 '... Air tank, 18, 19 ... Traction control valve (TRC valve), 20, 21 ... Slope start assisting valve (HSA valve; brake operation holding means), 22 ... ABS / TRC control unit (A
BS / TRC ECU), 22a ... HSA valve priority control means, 23 ... Clutch stroke sensor, 24 ... Clutch switch, 26 ... Neutral switch, 27 ... Parking brake switch, 28 ... Door switch, 29
… HSA operation switch, 30… Pilot lamp, 31
... Buzzer, 32 ... HSA control unit (HSA
ECU), 33, 34 ... Double check valve, 35,
36 ... Traction control cut valve (TRC
Cut valve)

Claims (4)

[Claims] 1. A wheel speed sensor for respectively detecting a wheel speed of a predetermined number of non-driving wheels and a wheel speed of a predetermined number of driving wheels,
A pressure source for supplying a pressure fluid for operating a brake of each wheel, at least one non-drive wheel brake of the non-drive wheels and at least one drive wheel brake of the non-drive wheels operated by the supply of the pressure fluid. A brake actuator that operates in common, a manual brake valve that is disposed between the brake actuator and the pressure source to control the supply and discharge of pressure fluid to and from the brake actuator, and the brake separately from the brake valve. A traction control valve that controls the supply and discharge of pressure fluid from the pressure source to the actuator;
A normally open traction control cut valve that is disposed in the brake fluid passage between the brake actuator and the one non-driving wheel brake and that blocks the brake fluid passage during traction control, and a predetermined value based on each wheel speed. Method to determine whether the drive wheels have a slip tendency, and when it is determined that the drive wheels have a slip tendency, turn on the traction control valve and turn on the traction control cut valve. In the traction control system, a traction control electronic control unit for controlling the traction control electronic control device is provided, and a brake operation holding means for holding the non-driving wheel brake and the driving wheel brake in an operating state when necessary, and the traction control. Provided in the roll electronic controller,
Traction control cut valve control means for outputting a control signal for turning on the traction control cut valve after the brake operation holding means releases the brake operation state when starting traction control. Control system. 2. A normally open hill start assisting operation valve that constitutes the brake operation holding means, is disposed in a fluid passage between the brake valve and the brake actuator, and controls the disconnection of the fluid passage. A hill start auxiliary operation switch for outputting a hill start auxiliary signal, operation control member operation detecting means for detecting an operation state of the operation control member of the vehicle and outputting an operation control member operation signal, and the hill start auxiliary operation switch On the basis of the slope start assist signal and the operation control member operation signal from the operation control member operation detection means, it is determined whether or not the slope start assist operation condition is satisfied, and it is determined that the slope start assist operation condition is satisfied. When the determination is made, the hill start auxiliary operation valve is turned on, and the hill start auxiliary signal and the operation control member operation signal are used based on the hill start auxiliary signal. When it is judged that the condition for canceling the start auxiliary operation is judged, and when it is judged that the condition for canceling the start auxiliary assist for the slope is judged, the slope auxiliary assist electronic control device for turning off the slope auxiliary assist operation valve and the traction control cut When the traction control is started by configuring the valve control means, when the hill start auxiliary operation valve is on, the hill start auxiliary operation valve is first turned off, and then a control signal for turning on the traction control cut valve is output. The traction control system according to claim 1, further comprising: a hill start auxiliary operation valve priority control means. 3. The slope starting auxiliary operation valve priority control means is a control means for turning on the traction control cut valve after a predetermined time has elapsed after turning off the slope starting auxiliary operation valve. Two
A traction control system equipped with the slope start assist device described. 4. The brake actuation holding means is a brake pedal for actuating and controlling the brake valve, and the traction control cut valve control means actuates the traction control cut valve after a predetermined time has elapsed after releasing the brake pedal. The traction control system according to claim 1, wherein the traction control system is a control unit that is turned on.