JPH07115611B2 - Vehicle acceleration slip control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle acceleration slip control device, and more particularly, to an output control of an internal combustion engine and a braking device when an acceleration slip of a driving wheel generated during vehicle acceleration is detected. The present invention relates to an acceleration slip control device for a vehicle that suppresses the rotation of drive wheels by using the hydraulic control.

[Prior Art] In recent years, the drive wheels are prevented from idling that occur when the vehicle starts or accelerates, and the rotation of the drive wheels is controlled so that the frictional force between the tires of the drive wheel and the road surface during vehicle acceleration is maximized. As a result, various types of acceleration slip control devices have been proposed that improve the running stability and acceleration of the vehicle.

For example, when an acceleration slip occurs, the throttle valve provided in the intake system of the internal combustion engine is driven in the closing direction to forcibly reduce the intake air amount, the output torque of the internal combustion engine is suppressed, and the rotation of the drive wheels is suppressed. There is also a method of directly controlling the rotation of the drive wheels by using a braking device mounted on the vehicle in order to instantaneously suppress the rotation of the drive wheels when an acceleration slip occurs.

However, the former acceleration slip control device that uses a throttle valve directly controls the intake air amount of the internal combustion engine in order to suppress the output torque, so that acceleration slip can be performed satisfactorily without deteriorating fuel consumption and exhaust gas. Although it can be suppressed, the conventional one is based on a simple opening and closing control of the throttle valve, such as closing the throttle valve when acceleration slip occurs and opening the throttle valve when acceleration slip does not occur, When an acceleration slip occurs while the vehicle is running, the throttle valve is closed as it is, a large engine brake is generated, and the vehicle vibrates back and forth, so that stable running performance cannot be obtained. Further, it takes some time from the closing of the throttle valve until the output torque of the internal combustion engine decreases, and it is impossible to instantaneously suppress the rotation of the drive wheels.

Moreover, the acceleration slip control device using the latter braking device,
Although the rotation of the drive wheels can be instantaneously suppressed, it becomes necessary to provide a special braking device in order to suppress the rotation of the drive wheels using only the braking device. That is, when the driving force is large, for example, when the gear position of the transmission is the first speed, an extremely large braking hydraulic pressure is required if the braking force is applied against the driving force, and the braking device itself is high. Since energy is consumed, the amount of heat generated is large and a brake pad or the like having a high durability is required. Therefore, a special braking device having a large braking force is not available in time for the conventional braking device.

Therefore, an acceleration slip control device has been proposed in which both the throttle valve and the braking device are combined.
(For example, Japanese Patent Application No. 59-208716) This type of acceleration slip control device mainly performs acceleration slip control using a braking device when fast response is required, for example, when acceleration slip is large. For example, when the responsiveness is not so required when the acceleration slip is small, the acceleration slip control mainly using the throttle valve is performed to reduce the load on the braking device and improve the drivability and safety of the vehicle. And when performing the acceleration slip control mainly using the above braking device, if a restriction is provided so that the throttle valve does not close below a certain opening, large engine braking does not occur, and the vehicle does not vibrate back and forth,
More stable running performance can be obtained.

[Problems to be Solved by the Invention] However, in the acceleration slip control device for a vehicle in which the throttle valve and the braking device are combined as described above, the braking device operates when an abnormality occurs in the brake hydraulic pressure control means for controlling the braking device. Since it does not work, sufficient acceleration slip control cannot be performed.

When the throttle valve opening is limited during the acceleration slip control mainly by the braking device described above, only weak engine braking works when fast response is required, for example, when the acceleration slip is large, and the drive wheels are not operated. The rotation of is difficult to control. Therefore, there is a problem that the acceleration slip control is not performed well when the acceleration slip control is required.

[Means for Solving the Problem] The present invention adopts the following means as a constitution of the invention in order to solve the above problems.

That is, the gist of the present invention is, as illustrated in the configuration diagram of FIG. 1, a throttle valve that is provided in an intake system of an internal combustion engine and that increases or decreases the output of the internal combustion engine by adjusting the amount of intake air. A throttle valve drive unit that opens and closes, a brake hydraulic pressure control unit that controls the brake hydraulic pressure of the braking device for the drive wheels, and an acceleration slip on the drive wheels when the vehicle accelerates. An acceleration slip control device for a vehicle comprising: slip control means for suppressing rotation of the drive wheels by suppressing output and controlling the brake hydraulic pressure control means to directly apply braking force to the drive wheels. An abnormality detecting means for detecting whether or not the brake hydraulic pressure control means is abnormal, and the brake hydraulic pressure control means by the abnormality detecting means. When the abnormality of the control means is detected, the control of the brake hydraulic pressure control means by the slip control means is prohibited, and the output suppression degree of the internal combustion engine after the control by the slip control means is started when the brake hydraulic pressure control means is normal. An acceleration slip control device for a vehicle, comprising: an output suppression and speeding-up means that makes the speed faster than that.

[Operation and Effect of the Invention] In the vehicle acceleration slip control device of the present invention configured as described above, when an acceleration slip occurs in the drive wheels during vehicle acceleration, the slip control means causes the throttle valve to open / close the throttle valve. By controlling the valve drive unit and adjusting the amount of intake air to the internal combustion engine, the output of the internal combustion engine is suppressed and the brake hydraulic pressure control means for controlling the brake hydraulic pressure is controlled to directly apply the braking force to the drive wheels. Add. As a result, the rotation of the drive wheels and, consequently, the acceleration slip are suppressed.

On the other hand, in such a control device, when an abnormality occurs in the brake hydraulic pressure control means, the control becomes unstable if the slip control by the brake hydraulic pressure control means is executed as it is. Therefore, when the brake hydraulic pressure control means is abnormal, the slip control using the brake hydraulic pressure control means may be prohibited. However, the slip control using the brake hydraulic pressure control means is simply prohibited, and the throttle valve drive section is used. If the slip control is executed only by the output suppression control of the internal combustion engine, the control responsiveness will decrease.

Therefore, in the present invention, an abnormality detecting means for detecting an abnormality in the brake hydraulic pressure control means is provided, and when the abnormality in the brake hydraulic pressure control means is detected by the abnormality detecting means, the output suppression speed increasing means is the slip control means. The control of the brake hydraulic pressure control means by the above is prohibited, and the output suppression degree of the internal combustion engine after the control by the slip control means is started is made faster than when the brake hydraulic pressure control means is normal.

As a result, according to the present invention, even when the brake hydraulic pressure control means is abnormal, the response of the slip control is not significantly deteriorated, and the control response of the sleep hydraulic pressure control means is normal and abnormal. It is possible to prevent the property from changing greatly and suppress the acceleration slip well.

On the contrary, in order to secure the responsiveness of the slip control when the brake oil pressure control means is abnormal, it is not necessary to increase the output suppression degree of the internal combustion engine using the throttle valve drive unit in advance. It is possible to prevent the output of the internal combustion engine from rapidly changing to cause a large engine brake and to vibrate the vehicle back and forth when the slip control is executed when the means is normal, so that the running stability of the vehicle can be secured.

Here, the acceleration slip of the drive wheel is detected by, for example, detecting the rotational speed of the drive wheel (drive wheel speed) using a vehicle speed sensor or the like, and calculating the drive wheel acceleration using the detected drive wheel speed as one parameter. However, when it is judged that an acceleration slip has occurred when the acceleration exceeds a predetermined value, or when the idle wheel speed other than the driving wheel speed is detected and the speed difference exceeds a predetermined value, the acceleration slip occurs. It may be detected by using a conventionally used acceleration slip detection method, such as determining that the occurrence of the slip occurs.

Further, the throttle valve used for the acceleration slip control as described above is a main throttle valve linked to the accelerator pedal, or a sub-throttle valve provided upstream or downstream of the internal combustion engine intake system provided with the main throttle valve. Either is fine.

Further, in the present invention, when an acceleration slip occurs in the drive wheels, the throttle valve drive unit is used to close the throttle valve and reduce the intake air amount to suppress the output of the internal combustion engine. Since the ignition timing and the fuel injection amount of the engine are controlled according to the reduced intake air amount, it is possible to suppress the output of the internal combustion engine without making a sudden change,
The rotation of the drive wheels will be smoothly suppressed. A DC motor, for example, can be used as the throttle valve drive unit that opens and closes the throttle valve.

On the other hand, the brake hydraulic pressure control means also operates when an acceleration slip occurs on the drive wheels, which is driven by the amount of depression of the brake pedal, for example, separately from the brake master cylinder that generates the brake hydraulic pressure. , A second master cylinder is provided, and when an acceleration slip occurs, this second
The master cylinder may be driven to control the brake oil pressure to suppress the rotation of the drive wheels.

In this case, when the driver depresses the brake pedal, the brake hydraulic pressure generated from the brake master cylinder and the brake hydraulic pressure generated from the second master cylinder are transmitted as they are to the braking device for the driving wheels. For example, even if the driver tries to step on the brake pedal during the acceleration slip control, the brake hydraulic pressure generated by the second master cylinder may prevent the brake pedal from being stepped on, which may cause the driver to feel uncomfortable. It is advisable to provide a hydraulic switching valve, such as a shuttle valve, in the hydraulic system so that the braking system can be operated by the larger one of the two hydraulic pressures without affecting each other.

Further, the abnormality detecting means is for judging whether or not the brake hydraulic pressure controlling means is abnormal. For example, it is determined that the coil of the solenoid used for valve switching of the brake hydraulic pressure controlling means is not broken or short-circuited. You should check.

Further, the slip control means controls the throttle valve drive unit and the brake hydraulic pressure control means to suppress the rotation of the drive wheels when the acceleration slip of the drive wheels occurs, but in this case, the output suppression degree of the internal combustion engine may be slow. On the contrary, if it is made too fast, the output of the internal combustion engine will change rapidly, large engine braking will occur, and the running stability of the vehicle will decline,
For example, as described in claim 2, it is preferable that the restricting means restricts the opening of the throttle valve from becoming a predetermined value or less.

Then, when the slip control means is provided with the regulation means for regulating the opening of the throttle valve to be equal to or less than the predetermined value, the output control speed-up means serves as the throttle opening of the throttle valve by the regulation means. If you ban the regulation, you can easily achieve it. That is, in this way, the throttle valve can be sufficiently closed according to the occurrence state of acceleration slip only when the brake hydraulic pressure control means is abnormal, and the output of the internal combustion engine can be rapidly reduced.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

First, FIG. 2 is a schematic configuration diagram showing an engine periphery and a hydraulic system of a braking device of a vehicle equipped with the acceleration slip control device of the first embodiment.

In the figure, 1 is an engine, 2 is a piston, 3 is a spark plug, 4 is an intake valve, 5 is a fuel injection valve, 6 is a surge tank, 7 is an air flow meter, and 8 is an air cleaner. An accelerator pedal 9 which is conventionally provided in the intake passage between the tank 6 and the tank 6.
In addition to the main throttle valve 10 that adjusts the intake air amount in conjunction with, the main throttle valve 10 driven by the DC motor 12
A sub-throttle valve 14 that adjusts the intake air amount is provided in the same manner as above, and the accelerator pedal 9 is
An accelerator sensor 16 that is turned on is provided.

Next, 21 is a brake pedal, 22 is a brake master cylinder that generates a brake hydraulic pressure according to the amount of depression of the brake pedal 21, 23 is a sub-master cylinder for generating a brake hydraulic pressure when an acceleration slip occurs, and 24 and 25 are the vehicle concerned. Left and right idler wheels, 26 and 27 are also left and right drive wheels,
Reference numerals 28 to 31 denote wheel cylinders provided on the wheels 24 to 27, respectively.

Here, a tandem type master cylinder is used as the brake master cylinder 22, and wheel cylinders 28 and 29 provided on left and right idler wheels 24 and 25 and left and right drive wheels 26,
The brake hydraulic pressure is transmitted to the wheel cylinders 30 and 31 provided on the 27 by different hydraulic systems. The brake oil pressure generated in the sub-master cylinder 23 is the oil pressure for braking the left and right drive wheels 26, 27, and this brake oil pressure is the brake oil pressure for the drive wheels output from the brake master cylinder 22. Similarly to the wheel cylinder 30,
A change valve 32, which is a shuttle valve, is provided in the hydraulic system from the brake master cylinder 22 to the wheel cylinders 30, 31 so that the brake hydraulic pressure generated by the brake master cylinder 22 or the sub master cylinder 23 is transmitted to the brake master cylinder 22. The larger hydraulic pressure is transmitted to the wheel cylinders 30 and 31 as it is.

Further, 40 is a hydraulic system for driving the sub-master cylinder 23 to generate brake hydraulic pressure when a slip occurs during vehicle acceleration, and a hydraulic pump for pumping oil flowing in this hydraulic system from a reservoir tank 41. 42, check valves 43 and 44 that prevent the backflow of the pumped oil, an accumulator 45 that stores the oil in a pressurized state to use this oil as an energy source for driving the sub-master cylinder 23, and a hydraulic pump. A hydraulic switch 46 that is turned on when the hydraulic pressure transmitted from 42 to the accumulator 45 falls below a predetermined pressure.
When the acceleration slip of the vehicle is detected by the process described later, the accumulator 45 is added to the sub master cylinder 23.
And a two-position valve 47 for driving the sub-master cylinder, the valve position of which is switched so as to transmit the oil of the predetermined hydraulic pressure stored in. A one-solenoid type solenoid operated valve is used for the two-position valve 47, which is normally fixed to the valve position shown in the figure by a spring, and by receiving a drive signal,
It will be switched to the other valve position.

Further, in the figure, 48a is a drive wheel speed sensor provided on the output shaft of a transmission (not shown) for detecting the average value of the rotational speeds of the drive wheels 26, 27, that is, the drive wheel speed, and 48b is an idle wheel 28. , The average value of the rotation speed of 29,
That is, in order to detect the idle wheel speed, for example, an idle wheel speed sensor provided on an idle wheel shaft (not shown), 49a is a main throttle opening sensor provided to detect the main throttle opening θ1, and 49b is Each of the sub-throttle opening sensors provided for detecting the sub-throttle opening θ2 is shown, and 50 is a drive wheel speed sensor 48a and an idle wheel speed sensor 4
8b, a signal from the main throttle valve sensor 49a, the sub throttle sensor 49b, the hydraulic switch 46, and the accelerator sensor 16 is received, acceleration slip is detected and the brake hydraulic pressure of the drive wheels 26 and 27 is increased, and at the same time, the sub throttle valve 14 By opening and closing the output of the engine 1 is reduced, the drive wheels 26, 27
In order to maintain the acceleration slip control process for suppressing the rotation of the hydraulic pump and the hydraulic pressure for driving the sub-throttle valve stored in the accumulator 45 at a predetermined pressure, a hydraulic control process for driving the hydraulic pump 42 is executed. It represents a control circuit composed of a microcomputer for detecting an abnormality of the two-position valve 47.

As shown in FIG. 3, the control circuit 50 includes an abnormality detection circuit 51, the accelerator sensor 16, the hydraulic switch 46, the drive wheel speed sensor 48a, the idle wheel speed sensor 48b, the main throttle valve sensor 49a, and the sub throttle sensor. The data detected by 49b and the abnormality detection circuit 51 are input and calculated according to the control program, and the hydraulic pump 42, the two-position valve 47, and
A central processing unit (CPU) 52 that performs processing for driving and controlling the DC motor 12, a read-only memory (ROM) 53 that stores data such as control programs and maps, data from the above sensors, and arithmetic control Random access memory (RAM) 54 for temporarily reading and writing the data required for input, input section 55 equipped with a waveform shaping circuit and a multiplexer for selectively outputting the output signals of each sensor to CPU 52, and hydraulic pump 42. An output unit 56 having a drive circuit for driving the two-position valve 47 and the DC motor 12 in accordance with a control signal from the CPU 52 is connected to each element such as the CPU 52 and the ROM 53, the input unit 55, and the output unit 56 to connect various data. A bus line 57 serving as a passage, and a power supply circuit 58 for supplying power to each of the above parts
It consists of and.

As shown in FIG. 4, the abnormality detection circuit 51 includes two transistors Tr1 and Tr2, one Zener diode ZD, and one Zener diode ZD.
It is composed of one knot gate Inv and five resistors R1, R2, R3, R4, R5. When the driving coil 59 of the two-position valve 47 is normal, the same signal as the signal from the output section 56 is input to the above. Department
When the drive coil 59 has an abnormality such as a disconnection or a short circuit, a signal different from the signal from the output unit 56 is output to the input unit 55. That is, the abnormality detection circuit
In 51, when the drive coil 59 is normal and the drive signal of the H level is output from the output unit 56, the transistors Tr1 and Tr2 are sequentially turned on, and the power supply B drives the drive coil 59 and the transistor Tr2. A current path is formed therethrough to the ground line, and the drive coil 59 is energized. When the drive signal of the L level is output from the output unit 56, the transistors Tr1 and Tr2 are sequentially turned off and the drive coil 59 is de-energized.

Then, the collector of the transistor Tr2 and the driving coil 59
The input of the knot gate InV is connected to the connection point with the resistor R2, and the output of this knot gate InV is directly input to the input unit 55. Therefore, the H level drive signal is output from the output unit 56. Is output, the transistor Tr2 is turned on, and the drive coil 59 is energized, the knot gate InV
Becomes L level, and the same H level signal as the drive signal is input to the input unit 55. On the contrary, the output section
The L-level drive signal is output from 56 and the transistor Tr
When 2 is turned off and the drive coil 59 is de-energized, the input of the knot gate InV becomes H level, which is substantially the same as the power supply voltage, and the input section 55 receives the same L level signal as the drive signal. To be done.

A Zener diode ZD is provided between the base and collector of the transistor Tr2.The Zener diode ZD is driven immediately after the transistor Tr2 changes from on to off and the drive coil 59 is de-energized. This is for protecting the transistor Tr2 from a surge voltage generated on the collector side of the transistor Tr2 by the energy accumulated when the power coil 59 is energized.

On the other hand, when the driving coil 59 is disconnected, when the H level driving signal is output from the output unit 56, both the transistors Tr1 and Tr2 are turned on, and the input of the knot gate InV becomes L level. Although the same H level signal as the drive signal is input to the input section 55, when the L level drive signal is output from the output section 56, even if the transistors Tr1 and Tr2 are turned off, the transistor T
Since the power supply voltage is not applied to the collector of r2, the input level of the knot gate InV becomes L level, and the input section 55
A signal of H level different from the drive signal is input to. Similarly, when the drive coil 59 is short-circuited to the ground line side, the input of the knot gate InV is at the L level. Therefore, when the drive signal is at the L level, the input section 55 is different from the normal state. An H level signal is input.

Therefore, the CPU 50 outputs the L-level drive signal from the output unit 56 to the abnormality detection circuit 51 while the abnormality detection circuit 51 is being output.
It is possible to determine whether or not the driving coil 59 is normal by taking in the signal level input to the input unit 55 from the above and determining whether or not the signal level is the same L level as the drive signal. That is, if the signal level is the L level, the drive coil 59 is normal, and if the signal level is the H level, it can be determined that the drive coil 59 has an abnormality such as a disconnection or a short circuit.

Next, the acceleration slip control and the hydraulic pressure control executed by the control circuit 50 configured as described above will be described in detail with reference to the flowcharts shown in FIGS.

First, FIG. 5 shows an acceleration slip control for detecting the acceleration slip and driving the two-position valve 47 and the DC motor 12 to suppress the rotation of the drive wheels 26, 27. When the process is started, step 101 is first executed, and the accelerator sensor 16
Based on the signal from, it is determined whether or not the vehicle is currently in an accelerating state. That is, as described above, the accelerator sensor
Since 16 is turned on when the accelerator pedal 9 is depressed, this processing determines that acceleration is being performed when the accelerator pedal 9 is depressed. If it is determined that the vehicle is in the accelerating state, the process proceeds to the subsequent step 102, while if it is determined that the vehicle is not in the accelerating state, the process of this routine is finished.

Next, at step 102, the drive wheel speed V is detected based on the detection signals from the drive wheel speed sensor 48a, the idle wheel speed sensor 48b, the main throttle sensor 49a and the sub throttle sensor 49b.
r, the idle wheel speed Vf, the main throttle opening θ1 and the sub-throttle opening θ2 are calculated, and the routine goes to the subsequent step 103.
Then, in step 103, the reference wheel speed Vt is calculated based on the calculated idle wheel speed Vf.

Here, the reference wheel speed Vt is the drive wheel speed Vr in the processing described later.
It is used to determine whether or not an acceleration slip has occurred on the drive wheels in comparison with, and is calculated using Vt = 1.2 x Vf. Note that this coefficient of 1.2 is for controlling the rotation of the drive wheels so that the maximum frictional force is generated between the tires of the drive wheels and the road surface during acceleration and the optimum acceleration is obtained, that is, the slip ratio becomes 20%. It is the set value.

In step 104, it is determined by the output of the abnormality detection circuit 51 whether the drive coil 59 of the two-position valve 47 is normal.
If it is determined to be normal, the process proceeds to the following step 105, and if it is determined to be not normal, the process proceeds to a throttle valve-based slip control routine 106 described later.

Step 105 to Step 109 following Step 104 are
The vehicle slip rate SR represented by the following equation is calculated using the drive wheel speed Vr and the idle wheel speed Vf, and it is determined whether the state in which the slip rate does not exceed 0.30 has continued for a certain time α or more.

SR = | Vr−Vf | / Vf That is, if it is determined in step 105 that SR> 0.30, the timer counter t is reset, and if it is determined that SR ≦ 0.30, the timer counter t is incremented by 1. . Next, if it is determined in step 109 that t <α, it is determined that it is necessary to suppress the rotation of the drive wheels with good responsiveness, and the control proceeds to the slip control mainly performed by the braking device in step 110. If t ≧ α, it is determined that it is not necessary to suppress the rotation of the drive wheels with high responsiveness, and the control proceeds to the slip control mainly based on the throttle valve in step 106.

Next, the slip control in step 106 will be described with reference to FIG.

When the control shifts to this step 106, whether or not the drive wheel speed Vr obtained in step 102 in step 200 exceeds the reference wheel speed Vt, that is, the slip ratio of the drive wheel is 20%.
To determine if the tire has begun to slip. When Vr> Vt, in order to prevent the acceleration slip, a flag F indicating that the DC motor 12 is driven in the closing direction of the sub-throttle valve 14 is set in step 201, and the process proceeds to next step 202. .

In step 202, when closing the sub throttle valve 14,
The target opening θ ₂ ′ of the sub-throttle valve 14 is set to the idle wheel speed.
The map A as shown in FIG. 9 using Vf as a parameter is set, and the routine proceeds to step 103.

On the other hand, if it is determined in step 200 that Vr ≦ Vt,
That is, if it is determined that the acceleration slip has not occurred on the drive wheels, the routine proceeds to step 204 and the flag F is reset. Then, in the next step 205, the sub throttle valve 14
The target opening degree θ ₂ 'of is calculated using a map B as shown in FIG. 10 using the deviation (Vr-Vt) between the drive wheel speed Vr and the reference wheel speed Vt as a parameter, and the routine proceeds to step 206.

In step 206, it is determined whether the target opening θ ₂ ′ of the sub throttle valve 14 obtained in step 205 is larger than the main throttle opening θ ₁ . And θ ₂ ′>
When it is θ ₁ , the routine proceeds to step 207, where the target opening θ ₂ ′ is set to the value of θ ₁ , and the routine proceeds to step 203 where θ
_{If 2} ′ ≦ θ ₁ , then the process proceeds directly to step 203.

The processing of steps 205 to 207 is added in consideration of delaying the response when acceleration slip occurs again when the auxiliary throttle valve 14 is fully opened when acceleration slip does not occur on the drive wheels. When it is a process and acceleration slip is likely to occur, the auxiliary throttle valve 14
Since it is not necessary to limit the drive in the opening direction of the main throttle valve 10 and the opening thereof to be larger than the opening of the main throttle valve 10, the target opening θ ₂ ′ is the throttle opening θ of the main throttle valve 10.
_The limit is not to exceed ₁ .

When the target opening θ ₂ ′ of the sub-throttle valve 14 is set as described above, step 203 is executed. In this step 203, the set target opening θ ₂ ′ and the above-mentioned target opening θ ₂ ′ are set in step 102. The determined sub-throttle opening degree θ ₂ is compared and the rotation speed Vs of the DC motor 12 is set according to the deviation. When setting the rotation speed Vs, a map C as shown in FIG. 11 is used.

Next, the slip control mainly performed by the braking device in step 110 will be described with reference to FIG.

When the control shifts to this step 110, in step 300,
Similar to step 200 described above, it is determined whether or not the tire has started to idle depending on whether or not the drive wheel speed Vr exceeds the reference wheel speed Vt. And if Vr> Vt, the next step
Move to 301.

Step 301 is to prevent the sub-throttle valve 14 from closing below a predetermined opening (85% in this embodiment). If the opening θ2 of the sub-throttle valve 14 is larger than 85%, the flag F is set. Is set in step 302, the target opening θ2 ′ is reduced by 1 unit in step 303, and the process proceeds to step 304. In addition, the opening θ2 of the auxiliary throttle valve 14 is set.
Is 85% or less, the target opening θ2 ′ is not changed and the routine proceeds to step 304.

In step 304, a drive signal is output to the two-position valve 47 to generate a brake pressure and the braking device suppresses the rotation of the drive wheels.

On the other hand, if it is determined in step 300 that Vr ≦ Vt, the flag F is reset in step 305, the process proceeds to the next step 306, and the target opening θ of the auxiliary throttle valve 14 is set.
After incrementing 2'by one unit, the process proceeds to step 307 to stop the drive signal to the two-position valve 47. As described above, the two-position valve 47 is in the valve position where the brake hydraulic pressure is not generated by the spring when there is no drive signal. Therefore, if the drive signal is stopped, the suppression of the rotation of the drive wheels by the braking device is released.

After outputting or stopping the two-position valve drive signal in step 304 or step 307, the control shifts to step 308. In step 308, as in the case of step 203, the set target opening θ2 ′ is compared with the sub-throttle opening θ2 obtained in step 102, and the rotation speed of the DC motor 12 is changed according to the deviation. Set Vs. When setting the rotation speed Vs, the 11th step is performed as in step 203.
A map C as shown in the figure is used.

Next, in FIG. 8, the DC motor is set in the opening direction or the closing direction of the sub throttle valve 14 based on the value of the rotational speed Vs of the DC motor 12 and the flag F obtained in the acceleration slip control routine of FIG. Drive and actually perform slip control,
This shows the DC motor control routine.

This processing is executed by interruption every predetermined time. When the processing is started, step 401 is executed first and the flag F
Is set, that is, whether or not the sub-throttle valve 14 is driven in the closing direction while acceleration slip is currently occurring. When the flag F is set, the routine proceeds to step 402, where the DC motor 12 is driven in the closing direction of the sub throttle valve 14 at the rotation speed Vs set at step 203 or step 308. On the other hand, when it is determined in step 401 that the flag F is in the reset state, the process proceeds to step 403, and the DC motor 12 is driven at the rotation speed Vs in the opening direction of the sub throttle valve 14. At this time, the rotation speed Vs may be "0", but in that case, the DC motor 12 is not driven.

Figures 12 and 13 show the acceleration slip control described above.
Drive wheel speed Vr, idle wheel speed Vf, when acceleration slip during vehicle start and acceleration slip during vehicle travel are controlled,
FIG. 12 is a time chart showing changes in the reference wheel speed Vt, the main throttle opening θ ₁ and the sub throttle opening θ ₂ , the two-position valve drive signal, and the timer counter t. FIG. 12 shows that the drive coil 59 is normal. Shows the time chart of the case,
FIG. 13 shows a time chart when the drive coil 59 is not normal. Incidentally, in FIG. 13, neither the two-position valve drive signal nor the timer counter t has been changed and therefore omitted.

As is clear from FIG. 12, in the acceleration slip control device of the present embodiment, the braking device is mainly operated only when it is necessary to immediately suppress the rotation of the drive wheels at the initial stage of acceleration slip or when the slip ratio is high. Since the acceleration slip control is performed, the conventional braking device having no particularly high durability can be used. Further, in the acceleration slip control mainly based on the throttle valve, when the drive wheel speed Vr exceeds the reference speed Vt and an acceleration slip occurs, the target opening θ ₂ ′ of the sub-throttle valve 14 becomes the idle wheel speed Vf, that is, the traveling of the vehicle. Since the sub-throttle valve 14 is set according to the speed and the sub-throttle valve 14 is closed accordingly, the engine output can be smoothly suppressed without generating a large engine brake when the vehicle is traveling. The rotation speed of the DC motor 12 that opens and closes the sub-throttle valve depends on the sub-throttle opening θ ₂ and the target opening θ.
_Since it is set according to the deviation from ₂ ', the sub-throttle valve 14 is quickly closed when a large acceleration slip occurs, and the sub-throttle valve 14 is gently closed when a small acceleration slip occurs. Will be done. Therefore, the sub-throttle valve can be opened and closed smoothly, and the over-control of the sub-throttle opening θ ₂ can be prevented. Further, the sub-throttle opening θ ₂ when the acceleration slip does not occur is not fully opened, is controlled according to the degree of slip of the drive wheels, that is, the slip ratio, and does not become larger than the main throttle opening θ _1. Therefore, the auxiliary throttle opening θ
₂ can be controlled to the target opening θ ₂ ′ earlier.

Further, as is apparent from FIG. 13, even if an abnormality occurs in the drive coil 59 and the acceleration slip control mainly by the braking device becomes impossible, the rotation of the drive wheels is suppressed by the acceleration slip control mainly by the throttle valve, so that the braking is performed. Although the responsiveness is slightly worse than in the case of mainly using the device, it is possible to execute the acceleration slip control which is sufficient for the stability of running of the vehicle.

Furthermore, in the acceleration slip control mainly of the throttle valve, like the acceleration slip control mainly of the braking device,
Since the lower limit of the sub-throttle opening θ2 is not limited and the sub-throttle opening θ2 is set as it is according to the slip state of the drive wheel, when the drive wheel 59 slips when the drive coil 59 is abnormal, Compared to when the output of the internal combustion engine is normal for the drive coil 59, the degree of output suppression of the internal combustion engine is faster, and the output of the internal combustion engine is more quickly suppressed. Therefore, when the drive coil 59 is abnormal, it is possible to prevent the responsiveness of the acceleration slip control from being significantly reduced as compared to when the drive coil 59 is normal.

Further, in the acceleration slip control mainly performed by the braking device, since the lower limit of the sub-throttle opening θ2 is limited, when the acceleration slip occurs, the output of the internal combustion engine sharply decreases, large engine braking occurs, and the vehicle moves forward and backward. It is possible to prevent the vibration.

In the present embodiment, it is determined whether or not the drive coil 59 of the two-position valve 47 is normal, and when there is an abnormality, a throttle valve-based control is executed. A series of processing from step 104 to step 106 is output. Corresponds to the speedup control means. In the above embodiment, the throttle valve provided in the intake system of the internal combustion engine is divided into two parts, one of which is the main throttle valve that works in conjunction with the accelerator pedal, and the other of which is the sub-throttle valve that is driven by the DC motor. In the case of a vehicle using a so-called linkless throttle valve that is configured to use the sub-throttle valve but does not work with the accelerator pedal, the link-less throttle valve without the sub-throttle valve for acceleration slip control as described above is provided. The acceleration slip control as described above can be carried out by directly controlling the drive of. In this case, the process of detecting the opening of the main throttle valve and opening the sub-throttle valve according to the opening of the main throttle valve as described above is not necessary. Therefore, the acceleration slip control can be further simplified. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention, FIGS. 2 to 13 show an embodiment of the present invention, FIG. 2 is a schematic configuration diagram thereof, FIG. 3 is a block diagram showing a control circuit, FIG. 4 is a circuit diagram showing an abnormality detection circuit, FIG. 5 is a flow chart showing a control program of an acceleration slip control routine executed by the control circuit, and FIG. 6 is a flow chart showing a control program of a throttle valve main slip control routine. FIG. 7 is a flow chart showing a control program of a braking device main slip control routine, FIG. 8 is a flow chart showing a control program of a DC motor control routine, and FIGS. 9 to 11 are maps used in the acceleration slip determination routine, respectively. The diagrams showing the contents of A to Map C, FIGS. 12 and 13 are changed by the acceleration slip control. Wheel speed is a time chart showing the throttle opening degree. 12 …… DC motor 14 …… Sub throttle valve 23 …… Sub master cylinder 26, 27 …… Drive wheel 32 …… Change valve 42 …… Hydraulic pump 47 …… Two position valve 48a …… Drive wheel speed sensor 48b …… Idling wheel speed sensor 50 ... Control circuit

Claims (2)

[Claims] 1. A throttle valve that is provided in an intake system of an internal combustion engine and that increases or decreases the output of the internal combustion engine by adjusting the amount of intake air; a throttle valve drive section that drives the throttle valve to open and close; and braking of driving wheels. Brake hydraulic pressure control means for controlling the brake hydraulic pressure of the device, and when acceleration slip occurs on the drive wheels during vehicle acceleration, the throttle valve drive part is controlled to suppress the output of the internal combustion engine and the brake hydraulic pressure control means is controlled. In a vehicle acceleration slip control device comprising: a slip control means for suppressing rotation of the drive wheel by directly applying a braking force to the drive wheel, whether or not the brake hydraulic pressure control means is abnormal. And an abnormality detecting means for detecting that the brake oil pressure control means has an abnormality. An output suppression quickening means for prohibiting the control of the brake hydraulic pressure control means by the control means and for making the output suppression degree of the internal combustion engine after the start of control by the slip control means faster than the normal time of the brake hydraulic pressure control means, A vehicle acceleration slip control device characterized by being provided. 2. The slip control means includes a regulation means for regulating that the opening degree of the throttle valve is equal to or less than a predetermined value, and the output suppression speed increasing means is an opening degree of the throttle valve by the regulation means. The vehicle acceleration slip control device according to claim 1, wherein the regulation of the above is prohibited.