JPH0692751B2 - Acceleration slip controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an acceleration slip control device that controls the output torque of an internal combustion engine to bring the slip ratio of a drive wheel closer to a target slip ratio.

[Prior Art] Conventionally, for example, JP 54-136033 A or JP
As described in JP-A-59-82544, the slip ratio of the drive wheel is calculated from the vehicle body speed (driven wheel peripheral speed) and the drive wheel peripheral speed, and the throttle opening is adjusted so that the slip ratio becomes the target slip ratio. Slip control devices for controlling are known. In this type of slip control device, when the drive wheel slip ratio is larger than the target slip ratio, the throttle opening is corrected to be reduced to reduce the output torque, and when the drive wheel slip ratio is smaller than the target slip ratio, the throttle opening is increased. Correct and increase the output torque. Then, by this, the slip ratio of the vehicle can be controlled to the target value and the acceleration of the vehicle can be improved.

[Problems to be Solved by the Invention] However, the change in the driving force with respect to the same output torque change amount becomes smaller as the gear ratio of the transmission is smaller. In the slip control device described above, the output torque is uniformly changed according to the slip ratio regardless of the gear ratio, and therefore, there are the following problems. That is, when the gear ratio is small, the change in driving force for the same slip ratio is too small,
The change in the drive wheel slip may be delayed and the convergence may be delayed. Further, when the gear ratio is large, the change in the driving force with respect to the same slip ratio becomes too large, the overshoot with respect to the target value of the slip ratio becomes large, and the convergence of the slip may be delayed.

Therefore, the present invention has been made for the purpose of providing an acceleration slip control device capable of quickly converging the drive wheel slip and obtaining good acceleration performance, regardless of which gear stage is selected.

[Means for Solving the Problems] The present invention made to achieve the above object is, as illustrated in FIG. 1, a drive wheel slip ratio for calculating a drive wheel slip ratio from a vehicle speed and a drive wheel peripheral speed. In an acceleration slip control device having a calculation means, and a control means for controlling the output torque of the internal combustion engine so that the slip ratio becomes the target slip ratio when the vehicle is accelerated based on the calculated slip ratio of the drive wheels, A shift speed detecting means for detecting the shift speed of the transmission is provided, and the control means changes the output torque in a larger change range as the gear ratio of the shift speed detected by the shift speed detecting means decreases. The gist of the invention is an acceleration slip control device characterized by being controlled by the following method.

[Operation] In the present invention thus configured, when the drive wheel slip ratio calculation means calculates the drive wheel slip ratio during vehicle acceleration,
The control means controls the output torque of the internal combustion engine so that the slip ratio becomes the target slip ratio. That is, the output torque is decreased when the drive wheel slip ratio is larger than the target slip ratio, and the output torque is increased when the drive wheel slip ratio is smaller than the target slip ratio.

On the other hand, the shift speed detecting means detects the shift speed of the transmission. And the control means. The smaller the gear ratio of the detected shift speed is, the larger the change range of the output torque is changed to be controlled.
For example, the change range of the output torque with respect to the deviation between the calculated drive wheel slip ratio and the target slip ratio is increased as the gear ratio is smaller.

When the gear ratio of the shift speed is small, the change in the driving force for the same output torque change is smaller than when the gear ratio is large. In the present invention, as the gear ratio of the shift speed is smaller, the output torque is changed with a larger change range as described above. Therefore, regardless of the shift speed, the driving force itself of the vehicle is changed according to the drive wheel slip ratio. You can

Therefore, no matter what speed is selected, the drive wheel slip can be quickly settled and the acceleration of the vehicle can be improved.

[Embodiment] Next, a preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a schematic configuration diagram showing an engine periphery and a wheel portion of a vehicle equipped with the acceleration slip control device according to the first embodiment of the present invention. In the figure, the combustion chamber of the engine 1 is composed of a cylinder 1a and a piston 1b. An ignition plug 1c is arranged in the combustion chamber. Further, the intake system includes an intake valve 1d, a fuel injection valve 1e, a surge tank 1f, an air flow meter 1g, and an air cleaner 1h. Here, a first throttle valve TP1 for adjusting the amount of intake air is provided in the intake passage between the surge tank 1f and the air flow meter 1g in conjunction with the accelerator pedal AP1. A second throttle valve TP2, which is driven by the DC motor TM2 and adjusts the intake air amount in the same manner as the first throttle valve TP1, is provided on the upstream side thereof.

On the other hand, the driving force generated by the engine 1 is transmitted to the left drive wheel RLW and the right drive wheel RRW via the transmission 2a, the propeller shaft 2b, and the like. The left idle wheel FLW and the right idle wheel FRW rotate as the vehicle runs. The left idle wheel FLW and the right idle wheel FRW are provided with idle wheel sensors SF1 and SF2 that generate a signal of a frequency corresponding to the number of rotations thereof. Further, the transmission 2a is provided with a drive wheel sensor SR1 that generates a signal having a frequency according to the average rotational speed of the left drive wheel RLW and the right drive wheel RRW.

The electronic control unit (hereinafter simply referred to as ECU) 10 receives the signals from the idle wheel sensors SF1 and SF2 and the drive wheel sensor SR1 described above, and at the same time, a DC motor TM2 that adjusts the opening degree of the second throttle valve TP2. To drive acceleration slip control.

Next, the configuration of the ECU 10 will be described with reference to FIG.

The ECU 10 inputs and calculates the data detected by each sensor described above according to a control program, and also performs a central processing unit (hereinafter simply referred to as CPU) 10a that performs acceleration slip control processing, such as the control program and a map described later. Read-only memory (hereinafter simply referred to as ROM) 10b in which data is stored in advance, random access memory (hereinafter simply referred to as ROM) in which data from each sensor described above and data necessary for arithmetic control are temporarily read and written.
It is called RAM) 10c.

Further, the ECU 10 includes an input unit 10d including a waveform shaping circuit for the output signal from each sensor described above, a multiplexer that selectively outputs the output signal to the CPU 10a, and an input port, a drive circuit for the DC motor TM2, and the drive circuit. The output unit 10e including an output port that outputs a control signal to the circuit, and the above-described C
The bus line 10f is provided as a data path between each element including the PU 10a and the ROM 10b.

Next, the acceleration slip control process executed by the ECU 10 will be described based on the flowchart shown in FIG.
This process is repeatedly executed at predetermined time intervals while the vehicle is traveling.

Step 105: Input section 10d from the driving wheel sensor SR1 described above
The rotational speeds of the drive wheels RLW, RRW are detected via. The wheel peripheral speed Vr of the drive wheels RLW and RRW is calculated based on the rotation speed.

Step 110: Similar to step 105 above, idler wheels FLW, FRW
The rotation speed of is detected. Then, the wheel peripheral speed Vf of the idler wheels FLW, FRW is calculated.

Step 115: Focusing on that the vehicle body acceleration α is substantially equal to the acceleration of the idle wheel, the idle wheel peripheral speed Vf calculated in step 110 is differentiated with respect to time to calculate the vehicle body acceleration α.

Step 120: Based on the vehicle body acceleration α calculated in the above step 115, the calculation for obtaining the road surface friction coefficient μ is performed as in the following expression (1). Here, assuming that the vehicle is traveling on a flat ground, considering the balance between the frictional force between the road surface and the drive wheels, the reaction force applied to each wheel from the road surface, and the rolling resistance force, the following equation (1 ), The road surface friction coefficient μ is calculated.

μ = (W × α + μr × W × g) / (Wr × g) (1) However, W ... Vehicle weight μr ... Rolling resistance coefficient g ... Gravity acceleration Wr ... Load on driving wheel Step 125: Above steps Based on the drive wheel peripheral speed Vr and the idle wheel peripheral speed Vf obtained in 105 and 110, the drive wheel slip ratio S is calculated as in the following equation (2).

S = (Vr−Vf) / Vr (2) Step 130: Based on the road surface friction coefficient μ calculated in the above Step 120, the maximum friction torque Tm between the driving wheel and the road surface is calculated by the following equation (3). ) Is calculated.

Tm = μ × Wr × R …………………… (3) However, R… Drive wheel radius Step 135: Drive wheel slip ratio S is reference slip ratio S ^*
The drive torque Tw is calculated by the following equation (4) so that

Tw = Tm + ΔT (4) However, ΔT is calculated by the following equation (5).

ΔT = K × (S ^* −S) (5) where K is a constant such as 50 to 200.

Further, S ^* is a first reference slip ratio, which is, for example, 0.1 to 0.3.
Is a value like.

The corrections performed by the above equations (4) and (5) are as follows. When the slip ratio of the drive wheels calculated in step 125 is S1 as shown in FIG. 5, that is, when the slip ratio is smaller than the first reference slip ratio S ^* , the drive torque Tw is calculated from the maximum friction torque Tm. Only ΔT is added and corrected to increase the slip rate so that it approaches the first reference slip rate S ^* .

On the other hand, when the slip ratio of the drive wheels is S2 as shown in FIG. 5, that is, when it is larger than the first reference slip ratio S ^* , the drive torque Tw is set to ΔT from the maximum friction torque Tm.
However, the slip ratio is reduced by subtraction correction so as to approach the first slip ratio S ^* .

Step 140: The engine output torque Te corresponding to the drive torque Tw obtained in the above step 135 is calculated by the following equation (6).

Te = Tw / (Kt × Zm × Zd × n × n) …………………… (6) However, Kt… torque converter torque ratio Zm… transmission gear ratio Zd… differential gear ratio n …… each Gear Transmission Efficiency The torque ratio Kt of the torque converter is determined by the characteristics of the torque converter and is stored in the ROM 10b in advance. Further, the gear ratio Zm of the transmission can be detected from a signal indicating the state of the electronically controlled transmission (ECT), and this signal generator corresponds to the shift stage detecting means.

Step 145: The second throttle valve opening degree θij is calculated from the map based on the engine output torque Te and the engine speed Ne obtained in the above step 140. It should be noted that the above-mentioned map means the engine output torque Te as shown in FIG.
Is a two-dimensional map in which the second throttle valve opening θij is defined by using both the engine speed Ne and the engine speed Ne as coordinate axes.
It is stored in M10b.

Step 150: The DC motor TM2 is driven to adjust the opening of the second throttle valve TP2 so that the opening of the second throttle valve TP2 becomes the opening θij calculated in step 145.

Then, it exits to NEXT and ends this processing. Thereafter, this processing is repeatedly executed at predetermined time intervals during the acceleration slip control.

In the first embodiment, the left idle wheel sensor SF1, the right idle wheel sensor SF2, the drive wheel sensor SR1, the ECU 10, and the ECU 10
The processing (105, 110, 125) executed by the above corresponds to the driving wheel slip ratio calculating means. Further, the processing (135, 140, 145, 150) executed by the ECU 10 corresponds to the control means.

As described above, in the first embodiment, as the gear ratio Zm of the transmission becomes smaller, the change range [ΔT / (Kt × Zm ×
Zd × n × n)] is increased. Therefore, the driving force of the vehicle itself can be changed according to the slip ratio S regardless of the gear ratio Zm. Therefore, no matter what speed is selected, the drive wheel slip can be quickly settled and good acceleration can be obtained. Further, in the first embodiment, the road friction coefficient μ of the road surface on which the vehicle is traveling is calculated based on the acceleration calculated from the rotational peripheral speeds of the idler wheels FLW and FRW, and the maximum friction determined by the road surface friction coefficient μ is calculated. Torque,
The drive torque is obtained by correcting based on the slip ratio S of the drive wheels and the first reference slip ratio S ^*, and the opening θij of the second throttle valve TP2 is controlled to the opening at which the drive torque is output. It is configured. Therefore, the driving wheels RLW and RRW are always rotated with the optimum driving force even when the vehicle is accelerated, so that the occurrence of acceleration slip and the like can be suppressed.

Further, the slip ratio S of the driving wheels is the first reference slip ratio S ^*.
Since the opening degree of the second throttle valve TP2 is constantly adjusted so that the slip state approaches, the slip state can be converged extremely quickly even if an acceleration slip should occur.

Further, since the road surface friction coefficient μ is constantly calculated, even if the road surface friction coefficient μ changes with changes in the road surface condition, it is possible to control the rotation of the drive wheels RLW, RRW with the optimum driving force. The advantage is that it is possible.

Further, when the drive wheels RLW and RRW are prevented from idling, excess fuel is not supplied to the engine 1, so that fuel efficiency performance is improved.

Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

The difference between the first embodiment and the second embodiment is that in order to prevent acceleration slip, the first embodiment adjusts the opening of the second throttle valve to control the driving force transmitted to the drive wheels. On the other hand, in the second embodiment, in addition to the adjustment of the opening of the second throttle valve, the brake is applied to the drive wheels.

FIG. 7 is a schematic configuration diagram showing a hydraulic system of an engine periphery of a vehicle equipped with an acceleration slip control device of a second embodiment of the present invention and a control means such as a brake. No. 1 around the engine
Since the configuration is the same as that of the embodiment, the last digit of the reference numeral and the subscript are the same and the description is omitted.

The brake system includes a brake master cylinder 2 that generates brake hydraulic pressure according to the amount of depression of the brake pedal 21.
2. As will be described later, during acceleration slip control, a sub master cylinder 23 that generates a brake hydraulic pressure by the hydraulic pressure of the power steering, and a change valve that selectively transmits the hydraulic pressures of the master cylinder 22 and the sub master cylinder 23.
24, wheel cylinders 25, 26 for idle wheels FLW, FRW, drive wheels RL
It is composed of W and RRW wheel cylinders 27 and 28, a hydraulic circuit 30 for performing anti-skid control, and a hydraulic circuit 40 for power steering.

Further, an idle wheel sensor SF that outputs a signal having a frequency corresponding to the rotational speeds of the idle wheels FLW and FRW, and a drive wheel sensor SR2 are also provided. Then, the electronic control unit (hereinafter simply referred to as ECU) 50 inputs signals from the above-mentioned sensors to control the above-mentioned second throttle valve TP12 and the above-mentioned brake system to perform acceleration slip control. .

Here, a tandem type master cylinder is used as the brake master cylinder 22, and the left and right idler wheels FLW, FR
Wheel cylinders 25 and 26 provided in W and left and right drive wheels
The brake hydraulic pressure is transmitted to the wheel cylinders 27 and 28 provided on the RLW and RRW by different hydraulic systems. In addition, the brake hydraulic pressure generated in the sub-master cylinder 23 is left
Used as hydraulic pressure for controlling the right drive wheel RLW, RRW,
The change valve 24 determines which of the brake hydraulic pressure and the hydraulic pressure generated in the brake master cylinder 22 is transmitted to the wheel cylinders 27 and 28 via the anti-skid hydraulic circuit 30. The change valve 24 has the structure of a shuttle valve and transmits the larger one of the two hydraulic pressures to the anti-skid hydraulic circuit 30.

The anti-skid hydraulic circuit 30 is based on a hydraulic path that transfers the pressure transmitted from the change valve 24 to the drive wheel wheel cylinders 27, 28 via the three-position valve 31, and is based on the pump 3
Pressurization by 2 and holding by switching the 3-position valve 31 and depressurization (pressure is released to the reservoir 33) are performed. Incidentally, 34,3
5, 36 are check valves, and the hydraulic path through the check valve 36 is for reducing the pressure (reducing the braking force) by operating the brake pedal when the 3-position valve 31 is "holding". Is. The 3-position valve 31 is controlled by the ECU 50,
The valve position a corresponds to "pressurization", b corresponds to "holding", and c corresponds to "decompression".

Next, the power steering hydraulic circuit 40 will be described.
The power steering hydraulic circuit 40 includes a hydraulic pump 42 that pumps oil flowing in the hydraulic circuit from a reservoir tank 41,
Check valves 43 and 44 for preventing the reverse flow of oil, a steering gear box 45, a hydraulic switch 46 that is turned on (low level) when the hydraulic pressure of the steering gear box 45 rises by steering, and a hydraulic pressure. Hydraulic pressure increased by pump 42 (hereinafter referred to as steering hydraulic pressure)
Is used only in the power steering hydraulic circuit 40 (corresponding to position e) or is transmitted to the sub-master cylinder 23 for acceleration slip control (corresponding to position f). Valve 47) and the oil pumped by the hydraulic pump 42 to the steering gear box 45 without throttling (corresponding to the position h) or by throttling to increase the pressure of this hydraulic circuit (position i). The two-position valve (hereinafter, referred to as PS booster valve) 48, which switches between the two. Here, idle wheel sensor SF and drive wheel sensor SR
2. The signal detected by the hydraulic switch 46 is input to the ECU 50. Then, the M / C pressure increasing valve 47 and the PS pressure increasing valve 48 together with the ECU 5 so as to supply the hydraulic pressure from the power steering hydraulic pressure circuit 40 to the sub master cylinder 23 during the acceleration slip control.
Switching is controlled by 0. In addition, the pump 32 of the anti-skid hydraulic circuit 30 also controls the ECU 5 during acceleration slip control.
Driven by 0 to generate hydraulic pressure.

As shown in FIG. 8, the ECU 50 has the same configuration as that of the first embodiment, and therefore the last digit of the reference numeral and the subscript are the first.
The same notation as the embodiment is used, and the description is omitted.

Next, the acceleration slip control process executed by the ECU 50 will be described with reference to the flowchart of FIG. still,
This process is repeatedly executed every predetermined time.

First, the outline of this processing will be described.

(1) When the slip ratio S of the drive wheels RLW, RRW is larger than the second reference slip ratio Sb ^* , the second value shown in the first embodiment is used.
In addition to the throttle valve control, the brake control that brakes the drive wheels RLW, RRW is started. That is, the drive wheel brake pressure increase signal I is output and the 3-position valve 31
The ON / OFF control is performed to the position of and the position of b to increase the brake hydraulic pressure to the drive wheel wheel cylinders 27 and 28.

(2) By the processing of (1) above, when the driving wheels RLW, RRW are actually braked and the wheel peripheral speed of the driving wheels RLW, RRW stops increasing, the brake hydraulic pressure is increased by the brake control at that point. To cancel. That is, the drive wheel brake holding signal is output and the three-position valve 31 is held at the position b to hold the brake hydraulic pressure in the drive wheel wheel cylinders 27 and 28.

(3) When the wheel peripheral speed of the drive wheels RLW, RRW starts to decrease due to the process of (2) and the slip ratio S of the drive wheels RLW, RRW becomes smaller than the second reference slip ratio Sb ^* , , Release the brake control. That is, the drive wheel brake pressure reducing signal D is output to set the three-position valve 31 to the c position to reduce the brake hydraulic pressure in the drive wheel wheel cylinders 27 and 28.

(4) In addition to the described second throttle valve control, the above control (1), (2), (3) is repeated, and the time for increasing and maintaining the drive wheel brake hydraulic pressure for each cycle is added. When the total time T becomes smaller than the reference time T0, it is determined that the driving wheel brake control is no longer necessary, and only the second throttle valve control is executed.

Next, details of this processing will be described.

Step 100: The same second throttle valve control processing as that executed in steps 105 to 150 of the first embodiment is performed.

Step 205: The state of the brake control flag F1 and the slip ratio S of the driving wheels calculated in the above step 100 and the second reference slip ratio Sb ^* are compared. Here, the brake control flag F1 is a flag having an initial value of 0 and indicating whether or not brake control is being performed. The second reference slip ratio Sb ^* is, for example, a value of 0.1 to 0.3, and is a value larger than the first reference slip ratio S ^* used for controlling the second throttle valve TP12 described above. .
That is, when the brake control is not performed and the drive wheel slip ratio S is larger than the second reference slip ratio Sb ^{*, the} routine proceeds to step 210. On the other hand, if either one of the above two conditions is not satisfied, that is, if the brake control has already been performed, or if the drive wheel slip ratio S is smaller than the second reference slip ratio Sb ^*, then go to step 215. move on.

Step 210: It is executed when the condition judgment of the above Step 205 is satisfied. That is, the drive wheel slip ratio S is the second
It is executed when the slip ratio is larger than the reference slip ratio Sb ^* and the brake control is not performed. Here, the brake control flag F1 is set, and the routine proceeds to step 215.

Step 215: When the condition judgment of step 205 is not satisfied, or after the above-mentioned step 210 is executed.
It is determined whether or not the brake control flag F1 has been reset. That is, when the brake control is being performed, the routine proceeds to step 220. On the other hand, when the brake control is not being performed, the process goes to NEXT and the present process is terminated.

Step 220: Based on the condition determination in Step 215 above,
That is, it is executed when the brake control is being performed. That is, the brake control is started and the drive wheels are actually
The brakes start to be applied to RLW, RRW, the wheel peripheral speeds of the drive wheels RLW, RRW are detected by the drive wheel sensor SR2, and it is determined whether or not the increase in the drive wheel peripheral speeds has stopped. Driving wheel
When the driving wheel sensor SR2 detects that the wheel peripheral speeds of RLW and RRW have stopped increasing, the routine proceeds to step 225. On the other hand, the driving wheel sensor indicates that the driving wheels RLW and RRW are not yet fully braked and the wheel peripheral speed is increasing.
If it is detected by SR2, the process proceeds to step 230.

Step 225: It is executed based on the condition judgment of the above step 220. In other words, the drive wheel sensor SR indicates that the drive wheels RLW and RRW are braked and the increase in the wheel peripheral speed has stopped.
When detected by 2, the brake peak detection flag F2 indicating that is set. And step 23
Go to 0.

Step 230: When the condition judgment of Step 220 is not satisfied, or after Step 225 is executed. Slip ratio S of drive wheels RLW, RRW and second reference slip ratio Sb ^*
And are compared. Drive wheel RLW, RRW slip ratio S is second
If it is smaller than the reference slip ratio Sb ^* , step 260
Proceed to. On the other hand, the slip ratio S is the second reference slip ratio.
If it is greater than or equal to Sb ^* , proceed to step 240.

Step 240: It is executed based on the condition judgment of the above step 230. The state of the drive wheel peripheral speed peak detection flag F2 is determined. If the drive wheel peripheral speed peak detection flag F2 is reset, that is, if the drive wheels RLW and RRW are not sufficiently braked, the routine proceeds to step 245. On the other hand, when the drive wheel peripheral speed peak detection flag F2 is set, that is, when the drive wheel sensor SR2 detects that the drive wheels RLW and RRW are braked and the increase of the wheel peripheral speed is stopped. , Go to step 255.

Step 245: It is executed based on the condition judgment of the above step 240. That is, it is executed when the driving wheel sensor SR2 detects that the driving wheels RLW and RRW are not sufficiently braked and the wheel peripheral speed is increasing. That is, the drive wheel brake pressure increase signal I is output, and the three-position valve 31 moves between the position a (pressure increase) and the position b (hold).
ON / OFF controlled. Here, the drive wheel brake pressure increase signal I is obtained by comparing the ON / OFF duty ratio with the above step.
Based on the road surface friction coefficient μ calculated in 100, it is changed as shown in Expression (7) below. The ON / OFF control cycle CYC is a value such as 20 to 100 [msec].

CON = Kb × μ + Ton ……………… (7) However, the time when CON… 3 position valve 31 is in position a Kb… Constant, 10 to 100 [msec] Ton… 3 position valve response time, about 10 [msec ] COFF = CYC-CON (8) However, COFF ... 3 Position valve 31 is in position b Step 250: Drive wheel brake boost signal I having the duty ratio calculated in Step 245 above. Is output.
Then, the three-position valve 31 reciprocates between the positions a and b at the above-described cycle to drive the drive wheel wheel cylinders 27, 2
Increase the brake oil pressure in 8. Then, exit to NEXT and return to step 100 again.

Step 255: It is executed based on the above step 240 condition judgment. In other words, the drive wheel sensor SR indicates that the drive wheels RLW and RRW are braked and the increase in the wheel peripheral speed has stopped.
Executed when detected by 2. The drive wheel brake holding signal is output and the three-position valve 31 is held at the position b. As a result, the hydraulic pressure in the drive wheel wheel cylinders 27, 28 is kept constant. Then, exit to NEXT and return to step 100 again.

Step 260: It is executed based on the condition judgment of the above step 230. That is, it is executed when the slip ratio S of the drive wheels RLW, RRW is lower than the second reference slip ratio Sb ^* .
The drive wheel peripheral speed peak detection flag F2 is reset. Then, it proceeds to step 265.

Step 265: The drive wheels RLW, RRW are fully braked,
This is executed when the driving wheel sensor SR2 detects that the reduction of the wheel peripheral speed has started. That is, the drive wheel brake pressure reducing signal D is output, the three-position valve 31 is moved to the position c, and the drive wheel wheel cylinders 27, 28 are moved to the reservoir 3.
3 and the wheel cylinders 27, 28 are depressurized.

Step 270: Executed following step 265. That is, before the depressurization process in step 265 is performed. 3-position valve in steps 250 and 255 above
The total time T of the drive wheel brake pressure increase signal output time and the drive wheel brake holding signal output time output to 31 is calculated.

Step 275: Total time T calculated in step 270 above
Is compared with the reference time T0. The total time T is the reference time T0
If it is more, it is determined that the brake control is still required, the process goes to NEXT and returns to step 100 again. On the other hand, when the total time T is less than the reference time T0, it is determined that the brake control is no longer required, and the routine proceeds to step 280. Here, the reference time T0 is a value such as 15 to 50 [msec].

Step 280: It is executed based on the condition judgment of the above step 275. That is, the brake control flag F1 is reset assuming that the brake control is no longer required.
Then, exit to NEXT and return to step 100 again.

Assuming that the brake control is no longer necessary, after the brake control flag F1 is reset in step 280, the condition of step 205 is satisfied again and the brake control is required until the condition of step 100 described above is reached. The second throttle valve control process is repeatedly executed.

Further, in the second throttle valve control processing executed in step 100, the opening degree θij of the second throttle valve TP12 is
The first throttle valve TP that works with the accelerator pedal AP11
When it becomes larger than the opening degree of 11, the processing for holding the second throttle valve TP12 in the fully opened position is performed. After that, each of the above processes is repeatedly executed as necessary.

As described above, in the second embodiment, the road surface friction coefficient μ,
In addition to adjusting the opening degree of the second throttle valve TP12 based on the transmission gear ratio Zm, the brake hydraulic pressure of the drive wheels RLW and RRW is also adjusted based on the road surface friction coefficient μ. Therefore, in addition to the effects of the first embodiment, the following effects are achieved.

That is, in the acceleration slip control, a portion having a quick response is executed by the brake control of the drive wheels RLW and RRW, and the drive control for a longer time than that of the brake control is performed by the second throttle valve control. Is quickly converged, and the acceleration slip control can be performed with good efficiency as a whole.

In addition, the driving force of the engine 11 is the second throttle valve TP12.
Since the braking force required for acceleration slip control is relatively small, the brake hydraulic system can be made smaller and lighter.

Further, in the second embodiment, the anti-skid hydraulic circuit 30 provided for performing anti-skid and the three-position valve are provided.
Since the acceleration slip control is performed using 31 and, it is possible to realize the acceleration slip control for controlling the rotation of the drive wheels with a simple configuration without requiring a dedicated hydraulic circuit or device for the acceleration slip control. It will be possible.

In addition, since the power steering hydraulic circuit 40 is used as the pressure source during acceleration slip control, a dedicated pressure source is not required, and it is slightly different from conventional vehicles equipped with an anti-skid control device and a power steering device. There is also an advantage that the acceleration slip control can be performed only by improving the above.

Although two embodiments of the present invention have been described above, the present invention is not limited to these embodiments.
Needless to say, the present invention can be implemented in various modes without departing from the scope of the present invention.

[Effects of the Invention] As described in detail above, in the acceleration slip control device of the present invention, the control means controls the output torque of the internal combustion engine by changing the output torque of the transmission with a larger change width as the gear ratio of the gear position of the transmission is smaller. . Therefore, the driving force itself of the vehicle can be changed according to the drive wheel slip ratio regardless of the gear position.
Therefore, no matter what speed is selected, the drive wheel slip can be quickly settled and good acceleration can be obtained.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of the present invention, FIG. 2 is a schematic configuration diagram of an engine periphery and wheels of a vehicle equipped with an acceleration slip control device of the first embodiment of the present invention, and FIG.
FIG. 4 is a block diagram for explaining the above, FIG. 4 is a flowchart of processing executed by the ECU in the first embodiment of the present invention, and FIG.
FIG. 6 is a graph showing the relationship between the road surface friction coefficient and the drive wheel slip ratio. FIG. 6 is a graph showing the relationship between the engine output torque, the engine speed and the second throttle valve opening. FIG. 8 is a schematic configuration diagram showing a hydraulic system of an engine periphery of a vehicle equipped with an acceleration slip control device of a second embodiment of the invention and a braking means such as a brake.
FIG. 9 is a block diagram for explaining the ECU, and FIG.
6 is a flowchart of a process executed by an ECU in the embodiment. 1,11 …… Engine TP2, TP12 …… Second throttle valve TM2, TM12 …… DC motor FLW …… Left idler wheel FRW …… Right idler wheel RLW …… Left drive wheel RRW …… Right drive wheel SF1 …… Left Idling wheel sensor SF2 …… Right idling wheel sensor SF …… Idling wheel sensor SR1, SR2 …… Drive wheel sensor 31 …… 3-position valve 27,28 …… Drive wheel wheel cylinder 10,50 …… Electronic control unit (ECU) 10a, 50a ... CPU

Claims (1)

[Claims] 1. A drive wheel slip ratio calculating means for calculating a drive wheel slip ratio from a vehicle body speed and a drive wheel peripheral speed, wherein when the vehicle is accelerated based on the calculated drive wheel slip ratio,
In an acceleration slip control device provided with a control means for controlling the output torque of the internal combustion engine so that the slip rate becomes the target slip rate, a shift speed detecting means for detecting the shift speed of the transmission is provided, and the control means is An acceleration slip control device, wherein the output torque is controlled by changing the output torque in a larger change range as the gear ratio of the shift speed detected by the shift speed detecting means is smaller.