JPH05338424A - Chassis for vehicle - Google Patents

Abstract

PURPOSE:To instantly recover from slip tendency of a wheel by providing a control device to increase pressure of a cylinder in order to increase surface reaction in the cease when a slip ratio exceeds a specified value. CONSTITUTION:At the time when an antilock brake device or a traction control device works and in the case when a slip ratio exceeds a specified value due to sudden lowering of a surface friction coefficient, a control device 34 of a suspension device increases pressure of cylinders 22e, 22f of a specified wheel (basically all wheels 23e, 23f in antilock brake control and basically a drive wheel in traction control) separately from attitude control of a vehicle. Consequently, it is possible to increase surface reaction of the specified wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has at least one of an anti-lock brake device for preventing a wheel from falling into a locked state during braking and a traction control device for preventing a wheel slip during acceleration.
The present invention relates to a vehicle chassis including a suspension device that controls the attitude of a vehicle by supplying / discharging pressure fluid to / from a cylinder interposed between a vehicle body side and each wheel side.

[0002]

2. Description of the Related Art At least one of an anti-lock brake device for preventing a wheel from falling into a locked state during braking and a traction control device for preventing a wheel from slipping during acceleration is provided. In a vehicle chassis including a suspension device that controls the attitude of a vehicle by supplying and discharging a pressurized fluid to and from a cylinder interposed therebetween, conventionally, when operating the antilock brake device or operating the traction control device. In this case, the suspension device merely controls the attitude of the vehicle.

[0003]

The antilock brake device described above recovers from the slip tendency of the wheels to some extent when the road surface friction coefficient sharply decreases during operation and the like. There was a problem that it took some time to do. Then, the behavior of the vehicle is apt to become unstable and the stopping distance becomes long until the slip tendency is recovered.

Similarly, in the above traction control device as well, when the road surface friction coefficient drastically decreases during operation, the slip tendency of the wheels becomes large to some extent, and the slip tendency of the wheels is recovered to some extent. There was a problem that it took time.
Then, the behavior of the vehicle tends to be unstable until the slip tendency is recovered.

Therefore, an object of the present invention is to immediately recover from a wheel slip tendency which increases when the road surface friction coefficient suddenly decreases when the antilock brake device or the traction control device is operated. It is to provide a vehicle chassis that can be used.

[0006]

In order to achieve the above object, the vehicle chassis of the present invention includes an anti-lock brake device for preventing the wheels from falling into a locked state during braking and a wheel slip during acceleration. And a suspension device for controlling the attitude of the vehicle by supplying and discharging a pressure fluid to and from a cylinder interposed between the vehicle body side and each wheel side. Therefore, the suspension device includes a control device that increases the pressure of the cylinder in order to increase the road reaction force when the slip ratio exceeds a predetermined value during the operation of the antilock brake device and the traction control device. It is characterized by having.

[0007]

According to the vehicle chassis of the present invention, when the anti-lock brake device or the traction control device is actuated, when the slip ratio exceeds a predetermined value due to a sudden decrease in the road surface friction coefficient, the suspension device In addition to the attitude control of the vehicle, the control device increases the pressure of the cylinder of a predetermined wheel (basically all wheels in antilock brake control, basically driving wheels in traction control). Thereby, the road surface reaction force of the predetermined wheel can be increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle chassis of the present invention will be described below with reference to the drawings. Here, in the following, an anti-lock braking device that prevents the wheels from falling into a locked state during braking, a traction control device that prevents slipping of the wheels during acceleration, and a suspension device that performs attitude control of the vehicle are provided. An example will be described. Note that the antilock brake device and the traction control device are the first control for deceleration and the latter control for acceleration, and basically do not operate simultaneously. 1 to 5 will be described with reference to FIGS. 1 to 5. Next, another embodiment of control contents between the anti-lock brake device and the suspension device will be described with reference to FIGS. 8 and the like, and finally, an embodiment of the traction control device and the control contents between the traction control device and the suspension device will be described with reference to FIGS.
Etc. will be described.

FIG. 2 is a block diagram showing an antilock brake device of this embodiment. In FIG. 2, reference numeral 1 is connected to a brake pedal 2 and hydraulic pressure is generated in response to an input of the brake pedal 2. A master cylinder, reference numeral 3 is a wheel brake (disc brake) for braking the wheel by brake fluid pressure. Here, the wheel brakes 3 are a wheel brake 3a for braking a front left wheel of the vehicle, a wheel brake 3b for braking a front right wheel thereof, a wheel brake 3c for braking a rear left wheel thereof, and a rear right wheel thereof. The wheel brakes 3d for braking the vehicle are provided with four wheel speed sensors 4a-4d for detecting wheel rotation information as signals. And the master cylinder 1 and the wheel brake 3
A modulator 7 for switching the hydraulic pressure path or the like is provided between the and, in response to a command from the controller 5 issued based on the information from the wheel speed sensors 4a to 4d.

There are two hydraulic paths, 6A and 6B, which communicate with the discharge port of the master cylinder 1.
6B then further branches into two systems at branch points 8A and 8B and the corresponding wheel brakes 3a-
The paths 9a to 9d are connected to 3d. The same subscripts A, B and a to d are attached to the respective components corresponding to the wheel brakes 3a to 3d, the routes 6A and 6B and the tributary routes 9a to 9d.

An electromagnetic normally open valve 1 is provided in the middle of each of the paths 9a to 9d.
0a to 10d are respectively arranged, and routes 12a to 12d are further branched from branch points 11a to 11d between the electromagnetic normally open valves 10a to 10d and the corresponding wheel brakes 3a to 3d. There is. In addition, among these, the paths 12a and 12d join at the meeting point 13A, and the meeting point 1 of the path 6A between the master cylinder 1 and the branch point 8A.
It becomes route 15A connecting to 4A, and routes 12b and 12c
Similarly, there is a path 15B that joins at the meeting point 13B and connects to the meeting point 14B of the path 6B between the master cylinder 1 and the branch point 8B.

Here, electromagnetic normally-closed valves 16a to 16d are arranged in the respective paths 12a to 12d, and the confluence 13 of the paths 15A and 15B.
Variable-capacity reservoirs 17A and 17B on the A and 13B sides,
Pumps 19A, 19B for sucking the brake fluid in the reservoirs 17A, 17B by driving the motor 18 to the confluence points 14A, 14B and discharging it toward the confluence points 14A, 14B.
Are provided respectively. In addition, each solenoid normally open valve 1
0a to 10d are provided with one-way valves 20a to 20d for preventing a reaction delay at the time of returning the brake, which bypass the electromagnetic normally open valves 10a to 10d, the electromagnetic normally closed valves 16a to 16d and the one-way valves. The directional valves 20a to 20d and the like constitute the modulator 7.

The modulator 7 is (a) a "pressure increasing mode" in which the electromagnetic normally open valves 10a to 10d are opened without being excited and the electromagnetic normally closed valves 16a to 16d are closed without being excited. (State shown in the drawing) (b) "Decompression mode" in which the electromagnetic normally open valves 10a to 10d are excited and closed, and the electromagnetic normally closed valves 16a to 16d are excited and opened (c) The electromagnetic normally open valves 10a to 10d Is set to one of the "holding modes" in which the electromagnetically closed valves 16a to 16d are closed without being excited and the electromagnetic brakes 16a to 16d are closed without being excited.
The communication of each hydraulic path between d and the master cylinder 1 is controlled.

Further, the electromagnetic normally open valves 10a to 10d and the electromagnetic normally closed valves 16a to 16d of the modulator 7 described above.
The wheel speed sensors 4a to 4d are connected to the controller 5.

Next, the antilock brake control by the controller 5 will be described step by step with reference to the flow chart shown in FIG.

The modulator 7 selects the pressure increasing mode during normal braking (when the antilock brake control is not operated). That is, when the driver depresses the brake pedal 2 to apply the brake, the brake fluid pressure generated in the master cylinder 1 is applied to each of the electromagnetic normally open valves 10a to 9d from each of the paths 6A and 6B to each of the paths 9a to 9d. Each wheel brake 3a through 10d
3d (the electromagnetic normally-closed valves 16a to 16d are closed at this time, so the paths 12a to 1d).
Brake fluid does not flow to 2d side).

[Step A1] When the engine is started,
First, the controller 5 performs initial setting, that is, an ABS flag set at the time of activation of an antilock brake control described later, a SLIP flag set when the slip ratio S exceeds a set value S ₀ described later, and a slip ratio S set value. The large slip time counter T _S for counting the time exceeding S ₀ is cleared.

[Step A2] Each wheel speed sensor 4a-4
Input the signal from d.

[Step A3] The wheel peripheral speed Rω and the wheel acceleration a, which is a differential value thereof, are calculated and decelerated based on the wheel information signals of the wheel speed sensors 4a to 4d input in the above [Step A2]. The simulated vehicle speed V set based on the change curve of the wheel peripheral speed Rω and the wheel peripheral speed Rω
The slip ratio S is calculated from (S = 1-Rω / V).

[Step A4] The ABS flag which is turned on when the antilock brake control is activated is in the set state (=
1) or in the non-set state (= 0),
If it is in the set state, the operation proceeds to [Step A8] described later, and if it is not in the set state, the operation proceeds to [Step A5].

[Step A5] Based on the acceleration a and the slip ratio S calculated in the above [Step A3], it is determined whether or not the antilock brake control is started.
Various ordinary methods can be applied to this determination method. An example is shown here, but this method is a method of comparing with a preset and stored threshold value. In this method, the slip ratio S increases beyond a predetermined threshold value and the acceleration a Is less than or equal to the predetermined threshold value, the wheels tend to lock and it is determined that the antilock brake control is to be started, and the process proceeds to the next [Step A6],
In cases other than the above, it is determined that the process is not started and the process proceeds to [Step A14] described later. The threshold value of the slip ratio S for determining that the antilock brake control is started is set to be smaller than a set value S ₀ described later.

[Step A6] The ABS flag indicating that the antilock brake control is in operation is set (=
1) Do.

[Step A7] The mode at the time of starting the antilock brake control, that is, the "pressure reduction mode" of the modulator 7 and the "drive mode" of the pumps 19A and 19B are selected, and the process proceeds to [Step A16] described later.

[Step A8] When the antilock brake control is activated (when the ABS flag is 1), the process proceeds from [Step A4] to [Step A8], and the slip calculated in [Step A3] It is determined whether or not the rate S exceeds a preset value (predetermined value) S ₀ set and stored in advance. If the slip ratio S exceeds the set value S ₀ , [Step A1
0], otherwise proceed to the next [Step A9]
Proceed to. Here, the set value S ₀ is appropriately set to be slightly larger than the slip ratio at which the road surface friction coefficient μ becomes maximum (when antilock brake control on a constant μ road surface is performed, the road surface friction coefficient μ is changed from a slip-free state). There are controlled between the slip ratio until the maximum, a sudden lower the road surface friction coefficient μ slip ratio would exceed the slip ratio the road surface friction coefficient μ becomes maximum), the set value S ₀
As a result, the refueling operation for recovering the slip ratio accompanying the antilock brake control operation to the cylinder of the suspension device described later is performed.

[Step A9] If it is determined in the above [Step A8] that the slip ratio S does not exceed the set value S ₀ , in this [Step A9] the SLIP flag is cleared (= 0) and the slip The large time counter T _S is cleared (= 0). In addition, these SLIP
The flag and the slip large time counter T _S are set and counted when the slip ratio S exceeds the set value S ₀ as described above, and these signals are used for the slip tendency recovery by the suspension device described later. Is a criterion for starting or ending the operation of refueling.

[Step A10] Above [Step A8]
If it is determined that the slip ratio S exceeds the set value S ₀ , the SLIP flag is set (= 1) and the slip large time counter T _S (initial value 0) is set to 1 in this [Step A10]. Count will be added.

[Step A11] Above [Step A3]
Based on the acceleration a and the slip ratio S calculated by the above, it is determined whether or not the antilock brake control is to be ended. Various ordinary methods can be applied to this determination method. Although one example is shown here, according to this method, the acceleration a and the slip ratio S are compared with a threshold value, and the slip ratio S decreases below a threshold value and the acceleration a decreases below a predetermined threshold value. When the state of decreasing tendency continues for a certain period of time, the lock tendency is avoided, so it is determined that the antilock brake control is to be ended, and the process proceeds to the next [Step A12]. It is determined that the process is not completed, and the process proceeds to [Step A15] described later. The threshold value of the slip ratio is also set smaller than the set value S ₀ as described above.

[Step A12] The ABS flag is cleared (= 0) as the antilock brake control is terminated.

[Step A13] The SLIP flag is cleared (= 0) and the large slip time counter T _S is cleared (= 0) with the end of the anti-lock brake control.

[Step A14] Above [Step A5]
If it is determined in step A11 that the antilock brake control is not started, if it is determined in step A11 that the antilock brake control is to be ended, then step A12 is
This [Step A14] is performed through [Step A13].
Then, the mode when the anti-lock brake control is not operated, that is, the "pressure increasing mode" of the modulator 7 is selected and the "non-driving mode" of the pumps 19A and 19B is selected, and the process proceeds to [Step A16] described later.

[Step A15] Above [Step A1
In 1], when it is determined that the antilock brake control is not ended, the process proceeds to [Step A15]. Here, based on the acceleration a and the slip ratio S calculated in the above [Step A3], the modulator 7
“Pressure increase mode”, “Depressurization mode”, or “Hold mode” is selected. As a method of switching these modes, various ordinary methods can be applied.
An example is shown here, but according to this method, the slip ratio S is equal to or less than a predetermined threshold value that is judged to have decreased during depressurization, and the acceleration a exceeds the predetermined threshold value to increase the acceleration tendency. If it is determined that the predetermined amount lock tendency has become smaller, the "pressure increase mode" is selected, and the slip ratio S exceeds the predetermined threshold value and increases, and the acceleration a tends to decrease below the predetermined threshold value. If it is determined that the wheels are in a lock tendency, the "decompression mode" is selected, and if the lock tendency is not extremely strong for finer control, the "pressure increase mode" and "decompression mode" are selected. The "hold mode" is selected at the boundary. Note that the threshold values of these slip ratios are also set smaller than the set value S ₀ as described above.

[Step A16] Above [Step A7]
The mode selected when the antilock brake control is started from the above, that is, the "pressure reduction mode" of the modulator 7, or the mode selected when the antilock brake control is not operated in [Step A14], that is, the "pressure increase mode" of the modulator 7, or [ In step A15], the modulator 7 receives any one of the “pressure increasing mode”, “pressure reducing mode”, and “holding mode” selected, and a command signal for switching the modulator 7 according to the selected mode is sent to the electromagnetic wave of the modulator 7. It outputs to the normally open valves 10a to 10d and the electromagnetic normally closed valves 16a to 16d. In response to this, the electromagnetic normally open valves 10a to 10d of the modulator 7 and the electromagnetic normally closed valve 1
6a to 16d are appropriately excited or demagnetized to switch the hydraulic pressure path between the master cylinder 1 and the wheel brakes 3a to 3d. The pumps 19A and 19B
Is always driven when the antilock brake control is activated.

When the "pressure reducing mode" is selected, the electromagnetic normally open valves 10a to 10d are closed to cut off the communication between the master cylinder 1 and the wheel brakes 3a to 3d. Electromagnetic normally closed valves 16a-1
By opening 6d, the wheel brakes 3a to 3d
The brake fluid on the side will flow into the reservoirs 17A and 17B. Therefore, the brake fluid pressure of the wheel brakes 3a to 3d is reduced.

When the "holding mode" is selected, the electromagnetic normally open valves 10a to 10d are closed to cut off the communication between the master cylinder 1 and each of the wheel brakes 3a to 3d, and at the same time, to prevent electromagnetic interference. Normally closed valves 16a-1
By closing 6d as well, reservoirs 17A, 17B
The inflow of brake fluid to the cylinder also disappears. Therefore, the brake fluid pressure of the wheel brakes 3a to 3d is kept constant.

Further, when the "pressure increasing mode" is selected, the solenoid normally open valves 10a to 10d are opened so that the master cylinder 1 and the wheel brakes 3a to 3d communicate with each other and the electromagnetic normally closed valve is opened. By closing 16a to 16d, the brake fluid on the wheel brakes 3a to 3d side does not flow into the reservoirs 17A and 17B. In this state, since the pumps 19A and 19B are constantly driven during the antilock brake control operation, the brake fluid flowing into the reservoirs 17A and 17B is sucked by the pumps 19A and 19B to the master cylinder 1 side. It discharges toward and increases the pressure of the wheel brakes 3a to 3d.

[Step A17] ABS information, that is, an ABS flag indicating the operation of the antilock brake control,
SL indicating that the slip ratio S exceeds the set value S ₀
An IP flag and a large slip time counter T _S for counting the time during which the slip ratio S exceeds the set value S ₀ ,
It outputs to the control device of the suspension device described later via the communication line. Then, after this [Step A17], the procedure returns to the above [Step A2].

Next, the structure of the drive wheel side of the suspension device of this embodiment will be described with reference to FIG. The configuration of the driven wheels is almost the same as that of the driving wheels except that the control device and the like are common, and therefore the description thereof is omitted. Further, since this suspension device is substantially left-right symmetric with respect to the axis of the vehicle body, the subscript e is attached to the left component in FIG. 4 and the subscript f is attached to the right component.

In FIG. 4, reference numeral 21 is a vehicle body, and reference numerals 22e, 22.
f is the vehicle body 21 and the axles 24e, 2 of the wheels 23e, 23f
4f show cylinders for vehicle height adjustment, which are interposed between the cylinders 4e and 4f, and these cylinders 22e and 22f are accumulators 25e and 25 as gas springs through throttles.
It communicates with f.

Further, each of the cylinders 22e and 22f is connected to a supply / discharge means 26 for supplying / discharging a pressure fluid composed of an oil liquid. The supply / discharge means 26 has a reservoir tank 27 for storing the pressure fluid and a reservoir tank 27 for storing the pressure fluid. A pump 28 that sucks in and discharges the pressure fluid in the reservoir tank 27, an accumulator 29 that holds the pressure fluid pumped from the pump 28 at a constant pressure, and a connection path between the cylinders 22e and 22f and the pump 28 are provided. Proportional flow control valves 30e, 30f installed
It is mainly composed of and. The supply / discharge means 26 is provided with control means (not shown) for controlling the operation of the pump 28 so that the pressure of the accumulator 29 is always constant.

Vehicle height sensors 31e and 31f are provided between the vehicle body 21 and the axles 24e and 24f, respectively, and these are based on the relative displacement between the vehicle body 21 and the wheels 23e and 23f. The vehicle height at the position is detected. Further, pressure sensors 32e and 32f are connected in the middle of the connection paths between the cylinders 22e and 22f and the proportional flow rate control valves 30e and 30f, respectively, to detect the pressure of the pressure fluid in the cylinders 22e and 22f.
The vehicle body 21 is provided with an acceleration sensor 33 that detects accelerations in the left-right direction and the front-rear direction that occur during turning or the like. The proportional flow rate control valves 30e, 30
f is designed to switch between the following three modes. (A) The cylinders 22e and 22f are communicated with the discharge side of the homp 28 of the supply / discharge means 26, and the cylinder 22 is connected.
"Flue refueling mode" for cutting off the communication between the e and 22f and the reservoir tank 27 of the supply / discharge means 26 (b) The cylinder 2e, 22f and the discharge side of the hoop 28 of the supply / discharge means 26 are cut off and the cylinder 2
"Holding mode" (state shown in the figure) that cuts off the communication between the supply / discharge means 26 and the reservoir tank 27 of the supply / discharge means 26 (c) Blocks the communication between the cylinders 22e, 22f and the discharge side of the hoop 28 of the supply / discharge means 26. With cylinder 2
2d, 22f and the reservoir tank 27 of the supply / discharge means 26 are in communication "oil drain mode"

Vehicle height sensors 31e, 31f, pressure sensor 3
The information detected by the 2e and 32f and the acceleration sensor 33 and the ABS information sent from the controller 5 of the antilock brake device are sent to the control device 34.

When the anti-lock brake control is activated, when the slip ratio S exceeds the set value S ₀ , the control device 34 is provided for early recovery from this slip tendency.
The control of the suspension device according to step 1 will be described step by step with reference to the flowchart shown in FIG. Note that normal control is applied to the vehicle height control and the like with the suspension device alone.

[Step B1] When the driver starts the engine, the control device 34 first clears the initial setting, that is, the information of the oil amount counter C _P described later.

[Step B2] Each vehicle height sensor 31e, 3
1f, pressure sensors 32e and 32f, and acceleration sensor 3
Input the signal from 3.

[Step B3] The vehicle height sensors 31e and 31f and the pressure sensor 32 input in the above [Step B2].
Based on the information from e, 32f and the acceleration sensor 33, each cylinder 22e, for performing normal vehicle attitude control,
An instruction amount P _SL for supplying / discharging the pressure fluid with respect to 22f is calculated. As this calculation method, various methods that are usually adopted can be applied. The instruction amount of oil supply / drainage is an instruction amount for oil supply / drainage of pressure fluid regardless of the amount of pressure fluid in each cylinder 22e, 22f at that time, that is, the oil supply / drainage amount for each control cycle. Is to determine, and + is refueling,
-Represents oil drainage, and when 0, the state is maintained.

[Step B4] ABS information of the antilock brake device (the ABS flag output in the above [Step A17] and indicating the operation of the antilock brake control,
SL indicating that the slip ratio S exceeds the set value S ₀
An IP flag and a large slip time counter T _S for counting the time during which the slip ratio S exceeds the set value S ₀ are input from the communication line connected to the controller 5. In addition, the controller 5 of the anti-lock brake device
And the control device 34 of the suspension device can transmit information by parallel or serial communication.

[Step B5] Whether the ABS flag indicating the operation of the antilock brake control is set in the ABS information of the antilock brake device input in the above [Step B4] (= 1) or not (= 0) To judge. If the ABS flag is set, the process proceeds to the next [Step B6], and if the ABS flag is not set, the process proceeds to [Step B7] described later.

[Step B6] Whether or not the SLIP flag indicating whether or not the slip ratio S exceeds the set value S ₀ in the ABS information of the antilock brake device input in the above [Step B4] is set. judge. If the slip ratio S is smaller than the set value S _{0, the} SLIP flag is not set (= 0), so the flow proceeds to the next [Step B7], and the slip ratio S is set value S _0.
If larger, SLIP flag is set (=
Since 1), the process proceeds to [Step B9] described later. That is, it is determined whether the slip ratio S exceeds the set value S ₀ while the antilock brake control is operating.

[Step B7] The SLIP flag is set when it is determined in [Step B5] that the ABS flag is not set (that is, when the antilock brake control is not operating) and in [Step B6]. When it is determined that there is no (= 0) (that is, when the antilock brake control is operating but the slip ratio S is equal to or less than the set value S ₀ ),
This [Step B7] is reached. And the oil amount counter C
The _P, anti-lock braking due to operation suspension control operation when the cylinder 22e, the oil amount of oil is supplied into the 22f is completely oil discharge (C _P = 0) or whether (C _P
≠ 0) is determined. Here, if it is determined that the oil has been completely drained, the process proceeds to [Step B16] described below, and the proportional flow rate control valves 30e, 30f are operated in accordance with the pressure fluid supply / drainage instruction amount P _SL for performing normal vehicle attitude control. Are appropriately operated to supply and discharge oil to and from the cylinders 22e and 22f. On the other hand, if it is determined that the oil has not been completely drained, the next [Step B
8].

[Step B8] The oil amount counter C _P is decremented by 1 and the oil supply / drainage instruction amount P _ABS is subtracted from the oil supply / drainage instruction amount P _SL of the pressure fluid for performing normal vehicle attitude control. Set the oil drainage command amount P _SL, and use [Step B1
6], the proportional flow rate control valves 30e and 30f are appropriately operated in accordance with the new oil supply / drainage instruction amount P _SL to supply and drain oil to the cylinders 22e and 22f. That is, the oil supply amount of the pressure fluid for controlling the suspension device associated with the anti-lock brake control, which was added to the oil supply / discharge amount of the pressure fluid for performing the normal vehicle attitude control, is changed to the oil supply / discharge instruction amount. than is for dividing waste oil in accordance with the P _ABS.
Note that this [Step B8] is for returning the amount of oil supply / drain for normal attitude control of the vehicle when the anti-lock brake device shifts to the inoperative state.

[Step B9] The above [Step B
6], the SLIP flag is set (= 1)
If it is confirmed, in this [Step B9], it is determined whether or not the slip large time counter T _S counted when the slip ratio S exceeds the set value S ₀ is less than or equal to the set time T _A. However, if it is equal to or less than the set time T _A , the process proceeds to the next [Step B10], and if not, the process proceeds to [Step B12] described later. When the slip ratio S exceeds the set value S ₀ during the antilock brake control operation, the set time T _A is set to the cylinders 22e and 22f of the suspension device in order to most efficiently recover from this slip tendency early. In addition to the refueling amount, the characteristics of the vehicle itself such as the vehicle weight, the height of the center of gravity, and the suspension characteristics, the set value S ₀ , the control characteristics of the antilock brake control, and the like are appropriately set. Then, the supply and discharge oil indicated amount P _ABS to fueling the set oil amount at time setting T _A will be set.

[0052] [Step B10] Here, the oil amount counter C _P is, the oil amount counter C _P calculated from the set time T _A
It is determined whether or not the maximum value _CPmax of the above is exceeded. This is to prevent the amount of oil supplied to each of the cylinders 22e and 22f from exceeding a predetermined amount set in advance despite satisfying the above [Step B9] for some reason. The relationship between the set time T _{A in} [step B9] and the ABS operation time counter, and the oil amount counter C _{P in} this [step B10] and its maximum value C _Pmax
When either one of the relations with and is satisfied, the supplementary refueling is stopped in order to recover from the slip tendency earlier. Then, the oil amount counter C _P shows the maximum value C.
_When it becomes _Pmax or more, it will be described later [step B16].
The proportional flow rate control valve 30 according to the supply / discharge instruction amount P _SL of the pressure fluid for performing the normal vehicle attitude control.
The cylinders 22e and 22f are operated by appropriately operating e and 30f.
You will need to supply and drain oil. On the other hand, if not, the process proceeds to the next [Step B11].

[Step B11] The oil amount counter C _{P is set} to 1
While counting adds, to supply and discharge oil indicated amount P _SL of pressure fluid for normal vehicle attitude control, the supply and discharge oil indicated amount P _ABS of the pressure fluid for performing suspension control associated with anti-lock brake control added And a new oil supply / drainage instruction amount P _SL is set, and the process proceeds to [Step B16] to be described later, and the proportional flow rate control valves 30e and 30f are appropriately operated according to the new oil supply / drainage instruction amount P _SL to operate the cylinders 22e. ，
Supply and drain oil to 22f. That is, the oil supply amount according to the oil supply / drainage instruction amount P _ABS is increased to the oil supply amount according to the oil supply / exhaust oil instruction amount P _SL before the addition.

[Step B12] Above [Step B9]
In the case where the slip amount of time counter T _S is determined to be not less than the set time T _A, determining whether the slip large time counter T _S in [step B12] is less than the new set time T _A + T _H To do. Here, T of this set time
_H is predetermined to keep the amount of oil supplied to each cylinder 22e, 22f of the suspension device in the constant state in order to recover from the slip tendency when the slip ratio S exceeds the set value S ₀ in an early stage. This set time T _H is also the characteristic of the vehicle itself such as the vehicle weight, the height of the center of gravity, and the suspension characteristic, the set value S _0, and the control of the antilock brake control so that the above-mentioned slip tendency recovery can be performed most efficiently. It is appropriately set according to the characteristics and the like. If the large slip time counter T _S is less than or equal to the new set time T _A + T _H , the process proceeds to step B16, which will be described later, and the supply / discharge command amount P of the pressure fluid for performing normal vehicle attitude control is provided. _The proportional flow rate control valves 30e and 30f are appropriately operated according to _SL to operate the cylinder 22e,
Oil will be supplied to and discharged from 22f. On the other hand, if not, the process proceeds to the next [Step B13].

[Step B13] It is determined whether or not the large slip time counter T _S is less than or equal to a new set time 2T _A + T _H. Here, the set time 2T _A + T _H
Is the cylinder 2 for the same amount of time T _A as when adding the oil supply amount that was added during T _A + T _{H in} order to recover early from the slip tendency when the slip ratio S exceeds the set value S _0.
This is the time for returning to the normal vehicle attitude control state by draining oil from 2e and 22f. When it is determined that the large slip time counter T _S is less than or equal to the new set time 2T _A + T _H , the process proceeds to the next [Step B14],
If not, the process proceeds to [Step B16], which will be described later, and the proportional flow rate control valves 30e, 30 are operated according to the supply / discharge instruction amount P _SL of the pressure fluid for performing normal vehicle attitude control.
The cylinders 22e and 22f are supplied and drained by appropriately operating f.

[Step B14] The oil amount counter C _P is set to "
It is determined whether or not it is 0 ". The oil amount counter _CP is"
If 0 "to proceed to the next [step B15], the process proceeds to later otherwise [step B16]. This is the maximum value C of the oil amount counter C _P in the above [step B10] oil amount counter _This is necessary because the oil amount counter C _P = 0 before the slip large time counter T _S reaches the set time 2T _A + T _H when limited by _Pmax .

[Step B15] The oil amount counter C _{P is set} to 1
Decrease the count and supply / drain oil instruction amount P _SL to oil supply / drain instruction amount P
_ABS is subtracted to obtain a new oil supply / drainage command amount P _SL, and the procedure advances to [Step B16] described later to obtain this new oil supply / drainage command amount P _SL.
Accordingly, the proportional flow rate control valves 30e and 30f are appropriately operated to supply and discharge oil to and from the cylinders 22e and 22f. That is, the slip ratio S, which is added to the supply / discharge oil amount of the pressure fluid for performing the normal vehicle attitude control, is the set value S _0.
This is to reduce the oil supply amount of the pressure fluid for early recovery from the slip tendency when it exceeds the limit by an amount corresponding to the oil supply / exhaust oil instruction amount P _ABS .

[Step B16] This [Step B1
[Step B7] and [Step B], which are the preceding stages of 6].
8], [Step B10], [Step B11], [Step B12], [Step B13], [Step B1]
4] and [Step B15], the proportional flow rate control valves 30e and 30f are appropriately operated according to the oil supply / drainage instruction amount P _SL output from them to supply / drain the oil to / from the cylinders 22e and 22f. Go to control that pressure. Then, the process returns to the above [Step B2].

Next, according to the vehicle chassis having the above structure,
The operation of the suspension device when the slip ratio S exceeds the set value S ₀ during the antilock brake control operation will be described mainly with reference to the operation diagrams of FIGS. 5A to 5D. 5 (a) to 5 (d) respectively show the front wheels of the vehicle.

First, the suspension system controls the posture of the vehicle to prevent a nose dive or the like when the brake is applied. That is, the vehicle height sensor 3
1e, 31f, the information detected by the pressure sensors 32e, 32f and the acceleration sensor 33 is sent to the control device 34, and the proportional oil flow control valve 30e corresponding to each of the proportional flow control valves 30e is calculated by calculating the oil supply / drainage instruction amount P _SL based on these information. , 30f are appropriately operated to supply pressure fluid to the cylinders 22e, 22f (in FIG. 5 (d), P _C0 represents the cylinder pressure when the suspension device is stopped on the horizontal road surface).

On the other hand, when the anti-lock brake device determines that the slip tendency becomes large during braking and anti-lock brake control is to be performed, the ABS flag is set and the "pressure-increasing mode" of the modulator 7,
The "holding mode" and the "decompression mode" are appropriately selected and operated, and the pumps 19A and 19B are operated.

Here, when the slip ratio S exceeds the set value S ₀ due to a sudden decrease in the road surface friction coefficient during the operation of the anti-lock brake device (at this point in time, FIG. In (d) indicated by A), the controller 5 sets the SLIP flag and the slip large time counter T _S starts counting every control cycle. At this time, the suspension device lowers the pressure of the front wheel cylinder that suppresses the nose dive by a predetermined amount up to B shown in FIGS. 5A to 5D.

At the above time point, the controller 5 transmits the information at this time, that is, the setting of the SLIP flag and the count number of the slip large time counter T _S , to the control device 34 of the suspension device, and in response to this transmission, The control device 34 supplies the oil supply / exhaust oil instruction amount P _SL to the oil supply / exhaust oil instruction amount P _ABS.
The cylinders 22e and 22f are refueled and drained on the basis of the new oil supply / drainage command amount P _SL that has been added, and this addition is repeated for a predetermined time T _A and a predetermined number of times so that each cylinder 22
A predetermined amount of pressure fluid is supplied to e and 22f, and the pressure increases as indicated by ΔP _C in FIG. 5D (from C to D shown in FIG. 5). Then, the control device 34 of the suspension device controls the cylinders 22e,
After the oil is supplied to 22f, this oil supply is stopped and this state is maintained for a predetermined time T _H (from D to E shown in FIG. 5).

The road surface reaction force to all the wheels (tires) 23e, 23f is increased by increasing the pressure of the above-mentioned cylinders 22e, 22f (actually, all the cylinders are shown in FIG. 4, only the drive wheels are shown). Therefore, all wheels 23e,
It is possible to quickly recover from the slip tendency that occurs when the slip ratio S exceeds the set value S ₀ when the antilock brake control is activated because the ground contact state with the road surface of 23f is improved. For comparison, FIG. 5 (a) shows the wheel speeds when the suspension device only performs normal attitude control (broken line) and the present embodiment (solid line). In the example, the wheel speed is switched from the decrease to the increase at an early stage even if the brake fluid pressure of the wheel brakes 3a to 3d is not lowered so much (see FIG. 5B) (this is when the antilock brake control is activated). This indicates that recovery from the slip tendency that occurs when the slip ratio S exceeds the set value S ₀ is quick.) Note that FIG.
In (a), the alternate long and short dash line indicates the vehicle body speed, and the alternate long and two short dashes line indicates the speed according to the set value S ₀ of the slip ratio.

[0065] As described above, the cylinder 22e of the suspension device, after performed a predetermined amount, a predetermined time oil supply to 22f, the control unit 34 of the suspension system, Tokoro depending on the summed supply and discharge oil indicated amount P _ABS from the sheet discharge oil amount that is quantified plus, each cylinder 22e will repeat the subtraction as many times as the number of additions, the pressure fluid from 22f by a predetermined amount oil discharge basically supplying and discharging oil indicated amount P _ABS (From E to F shown in FIG. 5). This allows
The suspension device returns to the normal oil supply / discharge oil amount for posture control.

Next, another embodiment of the antilock brake device and the suspension device for the vehicle chassis will be described. The present embodiment is mainly different from the above-mentioned embodiment in a part of the control contents of the controller of the antilock brake device and a part of the control contents of the suspension device. Explained.

First, some steps of the control contents of the antilock brake device of this embodiment different from those of the above embodiment will be described with reference to the flowchart shown in FIG. The same steps as those in the above embodiment are designated by the same identification A, and the description thereof is omitted.

When it is determined in [Step AA1] and [Step A8] that the slip ratio S does not exceed the set value S ₀ , in this [Step AA1], the SLIP flag is cleared (= 0) and the slip ratio S Difference S
Clear (= 0) _a (S _a = S−S ₀ ). The set value S ₀ is set in the same manner as in the above embodiment. Then, the process proceeds to [Step A11].

[Step AA2] When it is determined that the slip ratio S exceeds the set value S ₀ in [Step A8], in this [Step AA2], the SLIP flag is set (= 1) and the slip ratio S1 is set. Difference S _a (S _a
= S−S ₀ ) will be calculated. Then, the process proceeds to [Step A11].

[Step AA3] The SLIP flag is cleared (= 0) and the slip ratio difference S _a is cleared (=) as the antilock brake control is terminated.
0) and proceed to [Step A14].

[Step AA4] ABS Flag, SLI
The ABS information of the P flag and the slip ratio difference S _a is output to the control device of the suspension device described later via a communication line. Then, after this [Step AA4], the procedure returns to [Step A2].

Next, some steps of the control contents of the suspension device of this embodiment, which are different from those of the above embodiment, will be described with reference to B.
Description will be made with reference to the flowchart shown in FIG. The same steps as those in the above embodiment are designated by the same identification B, and the description thereof is omitted.

[Step BB1] ABS information of the antilock brake device (ABS flag output in [step AA4], which indicates the operation of the antilock brake control, and indicates that the slip ratio S exceeds the set value S _0. The SLIP flag and the slip ratio difference S _a ) are input from the communication line connected to the controller 5. Then, the process proceeds to the next [Step B5].

[Step BB2] If it is determined in [Step B5] that the ABS flag is set, in this [Step BB2], whether the SLIP flag is set (= 1) or not (= 0) ) Is determined.
Then, if the SLIP flag is set, the process proceeds to [Step BB5] described below, and if not, the process proceeds to the next [Step BB3].

[Step BB3] When it is determined that the ABS flag is not set in [Step B5] and when it is determined that the SLIP flag is not set in the above [Step BB2], this [Step BB3] ], The maximum slip ratio difference S _amax described later is cleared (= 0), and the process proceeds to the next [Step BB4].

[Step BB4] Counter T _SS described later
Is cleared and the process proceeds to [Step B7].

[Step BB5] Above [Step BB]
In 2], when it is determined that SLIP flag is set, in the [step BB5], it is determined whether the counter T _SS to be described later is 0, the following case is T _SS = 0 [ The process proceeds to step BB6], and when T _SS = 0 is not satisfied, the process proceeds to [step BB10] described later.

[Step BB6] Above [Step BB
5], when it is determined that the counter T _SS is 0, in this [Step BB6], the slip ratio difference S _a is the maximum value S of the slip ratio differences calculated and stored by then.
Determine if it exceeds _amax . If it exceeds, the process proceeds to the next [Step BB7], and if not, the process proceeds to [Step BB8] described later.

[Step BB7] The above [Step BB]
6], when it is determined that the slip ratio difference S _a exceeds the maximum value S _amax of the slip ratio difference, in this [Step BB7], the slip ratio difference S _a at this time is set as _a new slip ratio difference. The maximum value S _amax is stored.

[Step BB8] This [Step BB]
8] is the [step in BB6] If the slip rate difference S _a is judged not to exceed the maximum value S _amax of the slip ratio difference is the maximum value of the slip ratio difference of the time S _amax
If not, the maximum value C _Pmax of the oil amount counter is calculated according to the maximum value S _amax of the slip ratio difference newly stored in [Step BB7] (C _Pmax =
κ × S _amax : Specifically, when the slip ratio difference S _amax , C _Pmax is obtained by dividing the amount of refueling obtained by the characteristics of the vehicle itself, the control characteristics of the antilock brake, etc. by one refueling amount P _ABS. Therefore, by this C _Pmax and S _amax κ
Will be required).

[Step BB9] The oil amount counter C _P is compared with the maximum value C _Pmax of the oil amount counter calculated in the above [Step BB8], and the oil amount counter C _P is equal to or more than the calculated maximum value C _Pmax. When the slip ratio S exceeds the set value S ₀ , the process proceeds to the next [Step BB10] to stop the refueling of the pressure fluid for the early recovery from the slip tendency when the slip ratio S exceeds the set value S _{0. If P} is smaller than the calculated maximum value C _Pmax, [Step B11] is performed in order to replenish the pressure fluid for early recovery from the slip tendency when the slip ratio S exceeds the set value S _0. move on.

[Step BB10] Above [Step BB]
If it is determined in 5] that the counter T _SS is not 0, and if it is determined in [Step BB9] that the oil amount counter C _P is not smaller than the maximum value C _Pmax of the oil amount counter, then this [Step BB10] In, the counter T _SS is incremented by 1 count. Then, the process proceeds to the next [Step BB11].

[0083] [Step BB11] counter T _SS is equal to or less than the set value T _H, the process proceeds to the case TSS is below T _H [step B7], optionally oil amount counter C The calculation of _P and the subtraction of the oil supply / drainage command amount P _ABS are performed, and if not, the process proceeds to [Step BB12] to be described later and in accordance with the oil supply / oil discharge command amount P _SL for performing normal vehicle attitude control. The proportional flow rate control valves 30e and 30f are appropriately operated to supply and discharge oil to the cylinders 22e and 22f.

[Step BB12] This [Step BB]
12], which is the preceding stage [Step B7], [Step B
8], [Step BB11] and [Step B11]
As indicated, respectively, each proportional flow control valves 30e, 30 in accordance with supply and discharge oil indicated amount P _SL outputted from these
By appropriately operating f, the cylinders 22e and 22f are supplied and drained to control their pressures. And [Step B2]
Will return to.

By setting the control contents of the controller of the antilock brake device and the control device of the suspension device as described above, the slip ratio S exceeds the set value S ₀ during the control operation of the antilock brake device. The oil supply to the cylinders 22e and 22f of the suspension device for early recovery from the slip tendency is caused by the slip ratio difference S _a (S _a = S−S ₀ ), that is, the slip ratio S.
Will be done according to the size of. As a specific example, when the slip ratio difference S _a is large, the maximum value C _Pmax of the oil amount counter is increased in proportion to the slip ratio difference S _a (the maximum value S _amax of the slip ratio difference). Cylinder 22
When the lubrication time (lubrication amount) to e, 22f is increased and the slip ratio difference S _a is small, the maximum of the oil amount counter is proportional to the slip ratio difference S _a (the maximum value S _amax of the slip ratio difference). The value C _Pmax is reduced to reduce the lubrication time (lubrication amount) to the cylinders 22e, 22f, and therefore, the lubrication amount of the pressure fluid for recovering from the slip tendency at this time is substantially reduced. It is proportionally changed according to the slip ratio S.

Next, regarding the operation of the suspension device and the like when the slip ratio S exceeds the set value S ₀ at the time of operating the antilock brake control by the vehicle chassis having the above-described structure, the operation lines of FIGS. Description will be made mainly with reference to the drawings. 8 (a) to 8 (d) respectively show the front wheel side of the vehicle.

First, the driver applies the brake (this time is indicated by A in FIGS. 8A to 8D). Then, the anti-lock brake device sends information to the controller 5 from the detection by the wheel speed sensors 4a to 4d, and the controller 5 performs the above-mentioned calculation from this information.

On the other hand, the suspension device controls the attitude of the vehicle when the brake is applied to prevent a nose dive or the like. That is, the vehicle height sensor 3
1e, 31f, the information detected by the pressure sensors 32e, 32f and the acceleration sensor 33 is sent to the control device 34, and the proportional oil flow control valve 30e corresponding to each of the proportional flow control valves 30e is calculated by calculating the oil supply / exhaust oil instruction amount P _SL based on these information. , 30f are appropriately operated to supply the pressurized fluid to the cylinders 22e, 22f.
In this way, the attitude control of the vehicle is performed.
As shown in (a) to (d), normally, the time from the brake operation start time (A shown in FIG. 8) to the attitude control pressure increase completion (B shown in FIG. 8) is the antilock from the brake operation start time. The time is shorter than the time until the brake control start time (C shown in FIG. 8).

Then, when the antilock brake device determines that the antilock brake control is to be started based on the above calculation result and the like, the controller 5 sets the ABS flag and selects the "pressure reduction mode" of the modulator 7 ( C) shown in FIGS. 8A to 8D. Then, the modulator 7 blocks communication between the master cylinder 1 and the wheel brakes 3a to 3d, and stores the brake fluid on the wheel brakes 3a to 3d side in the reservoir 17A,
17B, the brake fluid pressure of the wheel brakes 3a to 3d is reduced.

Further, the controller 5 informs the control device 34 of the suspension device of the information at this time, that is, the ABS.
The flag is set, the SLIP flag is set, and the slip ratio difference S _a is transmitted. Then, the control unit 34 receives this transmission, the supply and discharge oil indicated amount P _SL newly obtained by adding the supplying and discharging oil indicated amount P _ABS to a supply and discharge oil indicated amount P _SL each cylinder 22e on the basis of, 22f of the supply and discharge Do the oil. Then, by appropriately changing the addition time according to the slip ratio difference S _a , the pressure fluid is supplied to the cylinders 22e and 22f substantially according to the magnitude of the slip ratio S.

Here, in FIGS. 8A to 8D, the case where the suspension device of this embodiment operates in a state where the road surface friction coefficient is high is shown by a broken line, and the case where the suspension device operates in a state where the road surface friction coefficient is low is shown. 8A and 8B, each of which is shown by a solid line and is described below (the one-dot chain line in FIG. 8A indicates the vehicle body speed, and the two-dot chain line indicates the speed according to the set value S0 of the slip ratio).

When the road friction coefficient is high, as described above, since the slip ratio difference Sa is small as described above, the maximum value C _{Pmax of the} oil amount counter calculated in accordance with the difference Sa is small.
Small, supply and discharge oil indicated amount P _SL to supply and discharge oil indication amount P _ABS based on the new supply and discharge oil indicated amount P _SL obtained by adding the respective cylinders 2
Time to supply and drain oil 2e and 22f (FIGS. 8A to 8D)
(From D to E) shown in FIG. The pressure in each of the cylinders 22e and 22f at this time is indicated by ΔP _CH in FIG. 8 (d). Then, the control device 34 of the suspension device is
After that, this refueling is stopped and this state is maintained for a predetermined time T _H (from E to F shown in FIG. 8).

After the cylinders 22e and 22f of the suspension device are refueled in this way,
The control device 34 of the suspension device basically repeats subtraction of the added supply / drain oil instruction amount P _ABS from the added supply / discharge oil amount by the same number of times as the number of additions. The pressure fluid is discharged from 22f (from F to G shown in FIG. 8). As a result, the amount of oil supplied and discharged for performing normal attitude control is restored. The change in hydraulic pressure of the wheel brake when the road surface friction coefficient is high is shown by the broken line in FIG. 8 (b).

On the other hand, when operating in a state where the road surface friction coefficient is low, the slip ratio difference S _a is large, so the maximum value C _Pmax of the oil amount counter calculated in accordance with this is large, and the oil supply / drainage command amount P _SL is large. The time for performing the oil supply / drainage of each cylinder 22e, 22f based on the new oil supply / drainage instruction amount P _SL that is obtained by adding the oil supply / drainage instruction amount P _ABS (from D to F shown in FIGS. Until) becomes longer. At this time, each cylinder 22e,
The pressure at 22f is indicated by ΔP _CL (greater than ΔP _CH ) in FIG. 8 (d). Then, the control device 34 of the suspension device is
After this, this refueling is stopped and this state is maintained for a predetermined time T _H (from F to H shown in FIG. 8).

Then, after the cylinders 22e and 22f of the suspension device are refueled in this manner,
The control device 34 of the suspension device basically repeats subtraction of the added supply / drain oil instruction amount P _ABS from the added supply / discharge oil amount by the same number of times as the number of additions. The pressure fluid is discharged from 22f (from H to I shown in FIG. 8). As a result, the amount of oil supplied and discharged for performing normal attitude control is restored. The change in hydraulic pressure of the wheel brake when the road surface friction coefficient is low is shown by the solid line in FIG. 8 (b).

Due to the increase in pressure in the cylinders 22e and 22f (actually, all cylinders are shown in FIG. 4 only on the drive wheel side), the slip ratio S exceeds the set value S _0. The road surface reaction force of the wheels (tires) 23e, 23f can be increased, the ground contact state of all the wheels 23e, 23f with the road surface is improved, and this slip tendency can be recovered early. Moreover, as described above, the oil supply to the cylinders 22e and 22f of the suspension device for recovering from the slip tendency at an early stage is caused by the slip ratio difference S _a.
That is, more detailed control is performed according to the magnitude of the slip ratio S.

Next, the structure of a traction control device for a vehicle chassis according to an embodiment of the present invention will be described below with reference to FIG. Reference numeral 42 in FIG. 9 denotes a pressure boosting cylinder, which includes the cylinder body 42a and the cylinder body 4
Basically, a piston 43 is slidably fitted in the 2a, and a hydraulic chamber 44 and a hydraulic chamber 45 are formed on both sides of the piston 43, respectively. A hole 42b is formed at the end of the cylinder body 42a on the hydraulic chamber 45 side, and the discharge port of the master cylinder 1 and the hydraulic chamber 45 are connected via the hole 42b and the pipe 46.

Inside the hydraulic chamber 45, there is a coil spring 47 arranged in the axial direction of the cylinder 42a for urging the piston 43 in a direction to reduce the hydraulic chamber 44, and a collar-shaped portion around the end of the cylindrical portion. A member in which the brim-shaped portion is formed between the end of the coil spring 47 on the hole 42b side and the inner surface of the cylinder body 42a, and the cylindrical portion is located inside the coil spring 47. 48, a valve rod 51 disposed in the cylindrical portion of the member 48 and having at one end a valve body 50 facing the valve seat surface 49 formed on the inner peripheral edge of the hole 42b, and the cylindrical shape of the valve body 50 and the member 48. Located between the valve and the valve stem 5
And a spring 52 for urging 1 toward the hole 42b.

A flange portion 51a formed at the other end of the valve rod 51 is slidably fitted in the piston 43, and between the coil spring 47 and the piston 43,
A pressing plate 53 provided so as to penetrate the valve rod 51 is interposed, and when the piston 43 moves in a direction of reducing the hydraulic chamber 44, the brim-shaped portion 51 a comes into contact with the pressing plate 53. That is, when the brake fluid pressure is applied to the fluid pressure chamber 44 and the piston 43 moves toward the hole 42b, the valve body 50 is seated on the valve seat surface 49, and the communication between the fluid pressure chamber 45 and the master cylinder 1 is cut off. Further, when the piston 43 moves in the direction of contracting the hydraulic chamber 44, the valve rod 51 is pushed toward the piston 43 against the biasing force of the spring 52, and the valve body 5
0 separates from the valve seat surface 49, and the hydraulic chamber 45 and the master cylinder 1 communicate.

Further, a hole 42c communicating with the hydraulic pressure chamber 45 is formed on the side wall of the cylinder body 42a, and the hydraulic pressure chamber 45 is connected to the hole 42c through a pipe 54 to drive the wheel brake wheel. 3X (if this vehicle is front drive, this becomes the wheel brakes 3a, 3b described above; if rear drive, it becomes the wheel brakes 3c, 3d). Further, in the pipe 46, the pipe 5
6 are connected so as to branch, and this pipe 56
And the wheel 46 of the driven wheel through the pipe 46
(If this vehicle is front driven, wheel brake 3
c, 3d, and wheel brake 3 if rear drive
a and 3b) and the discharge port of the master cylinder 1 are communicated with each other. A hole 42d communicating with the hydraulic chamber 44 is formed in the cylinder body 42a, and the hydraulic chamber 44 is provided with a pipe 58, an electromagnetic normally closed valve 59 and a pipe 60 which are sequentially connected from the hole 42d. Brake hydraulic pump 6
1 is connected to the discharge side. In the pipe 60, the pipe 60
An accumulator 63 is connected via a pipe 62 branched from. Here, the electromagnetic normally-closed valve 59 cuts off the communication between the pipe 58 and the pipe 60 in the normal state (the state in which the exciting voltage is not applied), and brings the two into the communicating state only when the exciting voltage is applied by the controller 70.

A pressure switch 83 is provided at the end of the pipe 82 branched from the pipe 60.
The brake hydraulic pump 61 is driven by rotating the motor 64 by the controller 70 based on the signal output from the pressure switch 83 when the accumulator 63 becomes low in pressure, and the suction side connects the pipe 65. It is connected to the liquid tank 66 through and sucks and discharges the liquid in the liquid tank 66. The liquid tank 6
6 is open to the atmosphere, and the internal pressure is always atmospheric pressure.

Further, the accumulator 63 is for accumulating the fluid discharged from the brake fluid pressure pump 61 and having a high pressure, and the electromagnetic normally closed valve 59 has a pipe 58 and a pipe 60.
When they are communicated with each other, the liquid having the high pressure is
It is designed to flow inside. The pipe 58 and the pipe 65 are the pipe 67 and the pipe 65 that branch from the pipe 58.
And a solenoid valve 69 provided between the pipe 67 and the pipe 68.
Here, the electromagnetic normally open valve 69 is the pipe 67 in the normal state.
And the pipe 68 are brought into communication with each other, and the communication between the two is cut off only when the excitation voltage is applied by the controller 70.

A drive wheel wheel speed sensor 4X for detecting the wheel speed of each wheel is provided near the drive wheel and the driven wheel (if the vehicle is a front drive, this becomes the wheel speed sensors 4a, 4b described above). , The wheel speed sensors 4c and 4d for rear drive) and the driven wheel speed sensors 4Y (wheel speed sensors 4c and 4d for front drive, and the wheel speed sensors 4a and 4b for rear drive). Is provided, and each output signal is input to the controller 70.

Then, in the controller 70, the following three modes are selected. (A) Since the brake hydraulic pressure is applied to the wheel brake 3X on the drive wheel side regardless of the depression of the brake pedal 2, the electromagnetic normally closed valve 59 is opened and the electromagnetic normally open valve 69 is closed, and the hydraulic chamber 44 is closed. The liquid on the pump 61 side is made to flow into the inside, the piston 43 in the pressure boosting cylinder 42 is moved to the hole 42b side, and the brake liquid in the hydraulic pressure chamber 45 is discharged toward the wheel brake 3X on the drive wheel side. Pressure Mode ”(b) In order to keep the brake fluid pressure constant, both the electromagnetic normally closed valve 59 and the electromagnetic normally open valve 69 are closed,
"Pressure holding mode" for keeping the hydraulic pressure in the hydraulic chamber 44 constant (c) In order to reduce the brake hydraulic pressure, the electromagnetic normally closed valve 59 is closed and the electromagnetic normally open valve 69 is opened.
The liquid in the hydraulic chamber 44 is made to flow into the liquid tank 66, the piston 43 in the pressure boosting cylinder 42 is moved to the opposite hole 42b side, and the brake liquid from the wheel brake 3X on the drive wheel side is made to flow into the hydraulic chamber 45. "Decompression mode"

Here, the controller 70 is communicatively connected to the control device 34 of the suspension device shown in FIG. Information can be transmitted between the controller 70 of the traction control device and the control device 34 of the suspension device by parallel or serial communication or the like as described above.

The traction control by the controller 70 will be described step by step with reference to the flowchart shown in FIG.

[Step C1] When the driver starts the engine, the controller 70 first clears initial settings, that is, a TRC flag, an oil amount counter I, etc., which will be described later.

[Step C2] Driving Wheel / Wheel Speed Sensor 4
X, signals from the driven wheel speed sensor 4Y, etc. are input.

[Step C3] The slip ratio λ and the like are calculated based on the wheel information from the driving wheel wheel speed sensor 4X and the driven wheel wheel speed sensor 4Y input in the above [Step C2]. That is, the wheel peripheral speed of the driven wheel, that is, the simulated vehicle speed V is calculated from the driven wheel wheel speed sensor 4Y, the wheel peripheral speed Rω of the driving wheel is calculated from the drive wheel wheel speed sensor 4X, and the slip ratio λ is calculated from them ( λ = 1-V / Rω).

[Step C4] [Step C1 to be described later]
0] determines whether the TRC flag set when the traction control is activated is in the set state (= 1) or in the non-set state (= 0). If the set state, proceed to the next [Step C5]. If it is not set, the operation proceeds to [Step C9] described later.

[Step C5] When it is determined in the above-mentioned [Step C4] that the TRC flag set during the operation of the traction control is in the set state (= 1), the traction control is ended based on the above-mentioned slip ratio λ and the like. It is determined whether or not to do. Various ordinary methods can be applied to this determination method. An example is shown here, but according to this method, the slip ratio λ
Etc. is compared with a preset and stored threshold value, and it is determined that the traction control is terminated when the slip ratio λ decreases below a predetermined threshold value and the slip tendency is avoided for a certain period of time. Then, the process proceeds to the next [Step C6]. On the other hand, in the case other than the above, it is determined that the process is not completed, and the process proceeds to [Step C8] described later.

[Step C6] The TRC flag is cleared (= when the traction control is finished.
0)

[Step C7] The above-mentioned [Step C5]
When it is determined that the traction control is to be ended, the "OFF mode", that is, the mode in which the electromagnetic normally closed valve 59 is closed and the electromagnetic normally open valve 69 is opened is selected.

[Step C8] [Step C described above]
If it is determined in step 4] that the TRC flag is set, and it is determined in step [C5] that the traction control is not to be ended, then in [step C8], the above-described modes are set to set the traction control. Will be done. As the traction control method, various ordinary methods can be applied. An example is shown here, but this method is used when it is determined that the slip ratio λ, etc. during traction control is less than or equal to a predetermined threshold value and the slip tendency of the drive wheels has decreased by a predetermined amount. Select "pressure reduction mode", and if the slip ratio λ, etc. increases beyond a specified threshold value and it is determined that the drive wheels are in a slip tendency, select "pressure increase mode" to perform more detailed control. Therefore, when the slip tendency is not extremely strong, the "pressure holding mode" is selected at the boundary between the "pressure increasing mode" and the "pressure reducing mode".

[Step C9] The above-mentioned [Step C3]
It is determined whether or not to start the traction control based on the slip ratio λ of each wheel calculated in. For this determination method, various ordinary methods can be adopted. An example is shown here, but according to this method,
When the slip ratio λ and the like are compared with a preset threshold value and the slip ratio λ is larger than this threshold value and it is determined that the driving wheels are in a slip tendency and the traction control is performed, the following [ Step C10]
On the other hand, when it is determined that the traction control is not started in any other state, the process proceeds to [Step C12] described later.

[Step C10] The TRC flag indicating that the traction control is in operation is set (=
1) Do.

[Step C11] A "rapid pressure increase mode" at the start of traction control, that is, a mode in which the electromagnetic normally closed valve 59, which is controlled to open / close at a normal duty ratio, is held in an open state is selected.

[Step C12] The above [Step C
When it is determined in 9] that the traction control is not started, the "OFF mode" described above is selected.

[Step C13] The above-mentioned [Step C
7], [Step C8], [Step C11] and [Step C12], the electromagnetic normally closed valve 59, the electromagnetic normally open valve 69 and the brake hydraulic pump 6 are selected.
Drive 1

[Step C14] The TRC information of the traction control is transferred to the control device 34 of the suspension device.
To send to. That is, the TRC flag is not set (= 0) when it is determined that the traction control is not started in [Step C9] and when the traction control is terminated in [Step C5]. If it is determined in step C9] that the traction control is started and if it is determined in [step C5] that the traction control is not ended, T
The fact that the RC flag is set (= 1) is transmitted to the control device 34 of each suspension device. Then, the process returns to the above [Step C2].

Next, regarding the control of the suspension device when the slip ratio S exceeds a set value S ₁ which will be described later during the operation of the traction control device,
Each step will be described with reference to the flowchart shown in FIG.

[Step D1] Similarly to the above, when the driver starts the engine, the control device 34 first clears the initial setting, that is, the oil amount counter I and the TRC operation counter T which will be described later.

[Step D2] Each vehicle height sensor 31e, 3
1f, pressure sensors 32e and 32f, and acceleration sensor 3
Input the signal from 3.

[Step D3] Based on the information from each sensor input in the above [Step D2], the supply / drainage command amount P _SL of the pressure fluid to each cylinder 22e, 22f is set in order to perform normal vehicle attitude control. Calculate Various calculation methods that are usually adopted can be applied to this.

[Step D4] The TRC information of the traction control device (TRC flag data and slip ratio S indicating the operation of the traction control output in the above [Step C10]) is provided to the controller 7 thereof.
Input from the communication line connected to 0.

[Step D5] TR showing the operation of the traction control input in the above [Step D4].
It is determined whether the C flag is set (= 1) or not (= 0). Then, if the TRC flag is set, the process proceeds to the next [Step D6], and if the TRC flag is not set, the process proceeds to [Step D10] described later.

[Step D6] The slip ratio S input in the above [Step D4] is compared with the preset and stored set value S ₁ to compare the slip ratio S with the set value S _1.
If it is above, proceed to the next [Step D7], and if not, proceed to [Step D10] described later. Here, since the traction control is to control from the state where there is no slip to the slip ratio where the road surface friction coefficient μ is the maximum, this set value S1 is more than the slip ratio where the road surface friction coefficient μ is the maximum. The value is appropriately set to a slightly large value, and by this set value S ₁ (and a set time T ₀ described later), a refueling operation for recovering the slip ratio accompanying the traction control operation to the cylinder of the suspension device described later is performed. Will be. The set value S ₀ is set to be larger than the threshold value of the slip ratio for determining the start of the traction control described above.

[Step D7] The TRC operation counter T (initial setting = 0) counted when the traction control is in operation and the slip ratio S is larger than the set value S ₁ during execution of the control cycle of this suspension device. Is incremented by 1 for each cycle.

[Step D8] The count number of the TRC operation counter T counted in the above [Step D7] is
It is determined whether or not it is equal to or shorter than the preset set time T ₀ , and if it is equal to or shorter than T ₀ , the process proceeds to the next [Step D9], and if not, the process proceeds to [Step D11] described later. In addition,
Slip rate S during traction control operation
In order to most efficiently and early recover from the slip tendency when T exceeds the set value S ₁ , the set time T ₀ is set in addition to the amount of oil supplied to each cylinder 22e, 22f on the drive wheel side of the suspension device, as well as the vehicle weight. , The height of the center of gravity, the suspension characteristics, and the like of the vehicle itself, the control characteristics of the traction control device, and the like. Then, the set refueling amount is set to the set time T
_In order to refuel at ₀ , the refueling / discharging instruction amount P _TRC is set.

[Step D9] The oil amount counter I (at the time of initial setting = 0) is incremented by 1 and the supply / drainage command amount P _SL of pressure fluid for performing normal vehicle attitude control is set to
The supply / drainage command amount P _TRC of the pressure fluid for performing suspension control for early recovery from the slip tendency is added to obtain a new supply / drainage command amount P _SL , which will be described later [Step D1.
3], the proportional flow rate control valves 30e and 30f on the respective drive wheels are appropriately operated in accordance with the new oil supply / drainage instruction amount P _SL to supply / discharge oil to / from the cylinders 22e and 22f. That is, the amount of oil supply / exhaust according to the amount of oil supply / exhaust instruction P _SL before addition is
The oil supply amount is increased according to the oil supply / exhaust oil instruction amount P _TRC . It should be noted that, regardless of traction control, each cylinder on the driven wheel side (not shown) is constantly supplied and drained with oil in accordance with the normal oil supply / drainage instruction amount P _SL (which does not adjust the oil supply / exhaust oil instruction amount P _TRC ). Become.

[Step D10] Above [Step D5]
In the case where the slip ratio S is determined to be not set values S ₁ or more when TRC flag is determined not to be set and [Step D6] is cleared TRC actuation counter T in the [Step D10] ( = 0).

[Step D11] Above [Step D8]
When it is determined that the TRC operation counter T is not equal to or less than the set time T _0, or when the TRC flag is not set in [Step D5], or the slip ratio S is not equal to or more than the set value S ₁ in [Step D6]. When the TRC operation counter T is cleared in step D10, it is determined whether the oil amount counter I is 0 or not. When the oil amount counter I is 0, the process proceeds to [Step D13] to be described later and the proportional flow rate control on the drive wheel side is performed in accordance with the pressure fluid supply / discharge instruction amount P _SL for performing normal vehicle attitude control. The valves 30e and 30f are appropriately operated to supply and discharge oil to and from the cylinders 22e and 22f. On the other hand, when the oil amount counter I is not 0, the process proceeds to the next [Step D12].

[Step D12] The above [Step D1]
1], it is determined that the oil amount counter I is not 0,
In this [Step D12], the oil amount counter I is decremented by one, and the supply / discharge oil instruction amount P _TRC is subtracted from the supply / discharge oil instruction amount P _SL of the pressure fluid for performing the normal vehicle attitude control. The instruction amount P _SL is set, and will be described later in [Step D1.
3], the proportional flow rate control valves 30e, 30f on the drive wheel side are appropriately operated in accordance with the new oil supply / drainage instruction amount P _SL to supply / drain oil to / from the cylinders 22e, 22f. That is, the oil supply amount of the pressure fluid for suspension control accompanying the traction control that is added to the oil supply amount of the pressure fluid for performing normal vehicle attitude control is _divided according to the oil supply / oil instruction amount P _TRC. Let them do it.

[Step D13] This [Step D1
[Step D9] and [Step D], which are the preceding stages of [3].
11] and [Step D12], the respective proportional flow rate control valves 30e, 30f on the drive wheel side are appropriately operated in accordance with the oil supply / exhaust oil instruction amount P _SL output from the cylinders 22e, 22f. Supply and drain the oil to control the pressure. Then, the process returns to the above [Step D2].

Next, the operation of the suspension device for early recovery from the slip tendency when the slip ratio S exceeds the set value S ₁ during the operation of the traction control by the vehicle chassis having the above configuration will be described with reference to FIG.
Description will be given mainly with reference to the operation diagrams of (a) to (c). It should be noted that all of these operation diagrams are on the drive wheel side.

First, the suspension device controls the attitude of the vehicle at the time when acceleration is started. That is, the vehicle height sensors 31e and 31f, the pressure sensor 32e,
Information detected by 32 f and the acceleration sensor 33 is sent to the control device 34, and the proportional oil flow control valve 30 e, which corresponds to the proportional oil flow control valve 30 e, which calculates the oil supply / drainage instruction amount P _SL based on the information.
30f is operated appropriately to supply the pressure fluid to each cylinder 22e, 22f.

On the other hand, the traction control device is
When it is determined that the slip tendency of the driving wheels becomes large at the time of acceleration and the traction control is performed, the TRC flag is set, the "rapid pressure increase mode" is selected, and the electromagnetic normally open valve 59 and the electromagnetic normally open valve 69 are operated.
The fact that the TRC flag has been set is transmitted to the control device of the suspension device. Then, the “pressure increasing mode”, the “holding mode” and the “pressure reducing mode” are appropriately selected, and the electromagnetic normally open valve 59 and the electromagnetic normally open valve 69 are appropriately operated in accordance with these.

Here, when the slip ratio S exceeds the set value S ₁ due to a sudden decrease in the road surface friction coefficient or the like during the operation of the traction control (at this point in time, FIGS. 12A to 12C). The control device 34 of the suspension device determines that the TRC operation counter T is 1
It starts counting in each control cycle, and, the supply and discharge oil indicated amount P _SL newly obtained by adding the supplying and discharging oil indicated amount P _TRC to a supply and discharge oil indicated amount P _SL Based on the drive wheel side of the cylinder 22e, 2
By supplying and discharging oil for 2f and repeating this addition for a predetermined time T ₀ and a predetermined number of times, a predetermined amount of pressurized fluid is supplied to each cylinder 22e, 22f (from t ₁ to t ₂ shown in FIG. 12). Until).

The drive wheel side cylinders 22e and 22f
Since the road surface reaction force to the drive wheels (tires) 23e, 23f can be increased by increasing the pressure of the drive wheels 23e,
It is possible to quickly recover from the slip tendency that falls when the slip ratio S exceeds the set value S ₁ during the operation of the traction control because the state of contact with the road surface of e and 23f is improved. For comparison, FIG. 12 (a) shows the wheel speeds when the suspension device only performs normal attitude control (broken line) and the present embodiment (solid line). Examples are wheel brakes 3a-3d
Even if the brake fluid pressure is not increased so much (Fig. 12
(See (b)) The wheel speed will switch from increase to decrease at an early stage (this indicates that the recovery from the slip tendency that occurs when the slip ratio S exceeds the set value S ₁ during traction control is quick. ing). In addition,
In FIG. 12A, the alternate long and short dash line indicates the vehicle body speed, and the alternate long and two short dashes line indicates the speed according to the slip ratio S ₁ .

As described above, after the suspension device cylinders 22e, 22f have been refueled for a predetermined amount and for a predetermined time, the suspension device control device 34 determines whether or not the suspension oil supply instruction amount P _TRC has been added. Basically, the supply / drainage command amount P _TRC is repeatedly subtracted by the same number of times as the number of additions from the supply / discharge amount of oil added in a fixed amount, and a predetermined amount of the pressure fluid is discharged from each cylinder 22e, 22f. (From t ₂ to t ₃ shown in FIGS. 12A to 12C). As a result, the amount of oil supplied and discharged for performing normal attitude control is restored.

In the above embodiments, the traction control device for controlling the brakes of the driving wheels has been described as an example, but the present invention is not limited to this. For example, for controlling the output of the engine or the brakes. It goes without saying that even if it is applied to any combination of control and engine control, a good effect is exhibited.

[0142]

As described above in detail, according to the vehicle chassis of the present invention, when the antilock brake device or the traction control device is operated, the road surface friction coefficient sharply decreases and the slip ratio becomes a predetermined value. If the vehicle exceeds the limit, the suspension system controller will control the cylinder pressure of the specified wheels (basically all wheels in antilock brake control and basically drive wheels in traction control) separately from the vehicle attitude control. As a result, the road surface reaction force of the predetermined wheel can be increased. Therefore, when the anti-lock brake device or the traction control device is operated, it is possible to immediately recover from the slip tendency of the wheel which increases when the road surface friction coefficient sharply decreases.

[Brief description of drawings]

FIG. 1 is a flowchart showing the control contents of a suspension device for a vehicle chassis according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing an antilock brake device for a vehicle chassis according to an embodiment of the present invention.

FIG. 3 is a flowchart showing the control contents of an antilock brake device for a vehicle chassis according to an embodiment of the present invention.

FIG. 4 is a configuration diagram showing a suspension device for a vehicle chassis according to an embodiment of the present invention.

FIG. 5 is an operation diagram of the antilock brake device and the suspension device during the antilock brake control operation of the vehicle chassis according to the embodiment of the present invention, in which (a) is a set value S of a vehicle speed and a slip ratio. Relationship between speed and wheel speed due to ₀ (vertical axis = speed, horizontal axis = time), (b) brake fluid pressure of wheel brake (vertical axis = hydraulic pressure, horizontal axis = time), (c) supply / discharge Oil indication amount (vertical axis =
Oil supply / discharging instruction amount, horizontal axis = time), and (d) shows cylinder pressure (vertical axis = pressure, horizontal axis = time), respectively.

FIG. 6 is a flowchart showing the control contents of an antilock brake device for a vehicle chassis according to another embodiment of the present invention.

FIG. 7 is a flowchart showing the control contents of a suspension device for a vehicle chassis according to another embodiment of the present invention.

FIG. 8 is an operation diagram of an antilock brake device and a suspension device at the time of operating an antilock brake control of a vehicle chassis according to another embodiment of the present invention, in which (a) is a set value of a vehicle speed and a slip ratio. Relationship between speed and wheel speed due to S ₀ (vertical axis = speed, horizontal axis = time), (b) brake fluid pressure of wheel brake (vertical axis = hydraulic pressure, horizontal axis = time), (c) supply / discharge Oil indication amount (vertical axis =
Oil supply / discharging instruction amount, horizontal axis = time), and (d) shows cylinder pressure (vertical axis = pressure, horizontal axis = time), respectively.

FIG. 9 is a configuration diagram showing a traction control device for a vehicle chassis according to an embodiment of the present invention.

FIG. 10 is a flowchart showing the control contents of the traction control device for the vehicle chassis according to the embodiment of the present invention.

FIG. 11 is a flowchart showing a control content at the time of traction control of the suspension device for the vehicle chassis according to the embodiment of the present invention.

FIG. 12 is an operation diagram of the traction control device and the suspension device at the time of operating the traction control of the vehicle chassis according to the embodiment of the present invention, in which (a) is a speed according to the set value S ₁ of the vehicle body speed and the slip ratio. And wheel speed (vertical axis = speed, horizontal axis = time), (b) brake hydraulic pressure of the wheel brake (vertical axis = hydraulic pressure, horizontal axis = time), (c) oil supply / drainage command amount ( Vertical axis =
The indicated oil supply / drainage amount and the horizontal axis = time) are respectively shown.

[Explanation of symbols]

 21 vehicle body 22e, 22f cylinder 23e, 23f wheel 34 control device

Claims (1)

[Claims] 1. An anti-lock brake device for preventing a wheel from falling into a locked state during braking and at least one of a traction control device for preventing a wheel from slipping during acceleration. In a vehicle chassis including a suspension device that controls the attitude of the vehicle by supplying and discharging a pressure fluid to and from a cylinder interposed between the suspension device and the suspension device, when the antilock brake device and the traction control device operate. In the vehicle chassis, there is provided a control device for increasing the pressure of the cylinder in order to increase the road surface reaction force when the slip ratio exceeds a predetermined value.