JPS61116034A - Acceleration slip control device for vehicle - Google Patents

Abstract

PURPOSE:To increase the output control range of an engine, by a method wherein an auxiliary throttle valve is situated on the upper stream or the downstream of a main throttle valve in the intake air system of an engine, and closing control thereof is controlled depending upon a car speed detected by a car speed detecting means. CONSTITUTION:A titled device comprises a driving wheel rotation state detecting means M2 which detects the rotation state of a driving wheel M1. The torque of an engine M3, transmitted to the driving wheel M1, is controlled by a control means M4 depending upon the rotation state of the driving wheel such that a friction force between the driving wheel M1 and a road surface is increased. In this constitution, an auxiliary throttle valve M9 is situated on the upper stream (or the downstream) of a main throttle valve M8, located in an intake sir system M7 and interlocking with an accel pedal M6. Closing operation of the valve M9 is controlled by an opening and closing control part M10 according to a car speed detected by a car speed detecting means M5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an acceleration slip control device for a vehicle. More specifically, the present invention relates to an acceleration slip control device for a vehicle that detects the rotational state of a drive wheel, controls a sub-throttle valve accordingly, suppresses engine output, and performs optimal acceleration slip control. It is.

[Prior Art] Starting and running on a road surface with a low RPHJ coefficient, such as on ice or snow, is extremely dangerous because the drive wheels may slip and cause the vehicle to spin. Therefore, in the past, spiked tires, chains, etc. were installed to increase the coefficient of friction between the tires and the road surface.

In addition, a traction control system that suppresses the slip of the drive wheels has been considered, and the slip ratio [(vehicle speed - drive wheel speed) / drive wheel speed] is set at -0°1 to -0°1 to maximize the road friction coefficient. This is intended to suppress and control the engine output, etc. so as to control it to around -0.2. This engine output control includes the following. That is, zero ignition angle control, fuel cut, fuel cut for each cylinder, and linkless throttle valve system, that is, the throttle valve is controlled when slip occurs.

As a result of suppressing engine output, acceleration slip is suppressed and safe driving is ensured.

[Problems to be Solved by the Present Invention] However, the above-mentioned conventional technology has the following problems. That is, regarding (2), since the torque control range is narrow, it is not effective on low friction coefficient road surfaces.

Regarding (①), a shock occurs when the fuel cut is restored.

Regarding (2), the shock when the fuel is restored is small, but the problem arises when photographing when the cylinders are depleted.

Regarding ■, there was a problem with reliability because it was a linkless mechanism.

Means 1 for Solving the Problem The present invention provides a sub-throttle valve in addition to the main throttle sensor, and uses this to solve the above-mentioned problem. That is, as shown in the basic configuration diagram of FIG. 1, the present invention includes a drive wheel rotation state detection means M2 that detects the rotation state of the drive wheel M1, and a drive wheel rotation state detection means M2 that detects the rotation state of the drive wheel M1; Drive wheel M
In the vehicle acceleration slip III system, the control means M4 includes a control means M4 for suppressing the torque of the engine M3 transmitted to the drive wheels M1 so as to increase the frictional force between the drive wheels M1 and the road surface, the control means M4 detecting the vehicle speed. A vehicle speed detection means M5, a sub-throttle valve M9 provided upstream or downstream of the main throttle valve M8 provided in the intake system M7 of the engine M3, which is interlocked with the accelerator pedal M6, and control for opening and closing of the sub-throttle valve M9. Acceleration slip control for a vehicle, characterized in that the opening/closing control section M10 is configured to control the closing control of the opening/closing control in accordance with the vehicle speed detected by the vehicle speed detecting means M5. i
Il! ! The gist is the device.

[Operation] The rotational state detection means detects the rotational state of the driving wheels, that is, whether or not the driving wheels are in a state immediately before slipping and idling. This detection generally uses driving wheel speed or driving wheel acceleration. After detecting the state, the opening/closing control section controls the sub-throttle valve to close and suppresses the engine output, and otherwise holds the sub-throttle valve or controls the sub-throttle valve to close to suppress a drop in driving wheel speed. Furthermore, by using the sub-throttle valve, the control range of engine output is widened, so even in the event of a failure,
It is safe because the main throttle sensor is activated.

[Example] The present invention will be described below with reference to examples and drawings.

FIG. 2 is a schematic configuration diagram of one embodiment, which is a front engine/rear drive (FR type) vehicle equipped with a gasoline engine. 7J11 to which the present invention is applied. In the figure, 1 is a four-cylinder fuel injection engine, 2 is an intake pipe, 3 is an air flow meter, 4 is a fuel injection valve provided for each cylinder that injects fuel into the intake air, and 5 is a spark plug In Figure 2, the fuel injection valve 4 and spark plug 5 are shown for only one cylinder.), 6 is a distributor that supplies high voltage to the spark plug, 7 is the tooth width, and 1! An engine speed sensor consisting of a magnetic pickup; 8 is a main throttle valve that is driven via a link mechanism in response to depression of an accelerator pedal 9 to adjust the amount of intake air; 10 is provided upstream of the main throttle valve 8 to measure the amount of intake air; 11 is a sub-throttle valve that adjusts the sub-throttle valve;
12 is a main throttle sensor for detecting the throttle valve opening of the main throttle valve 8, and 13 is a sub throttle sensor for detecting the throttle opening of the sub throttle valve 10. This throttle sensor 12.1
Reference numerals 3 and 3 each turn on when the above-mentioned suttle valves 8 and 10 are in the fully open position.

On the other hand, 20 and 21 are the left and right drive wheels, which are the rear wheels of the VJ vehicle, respectively, and the power from the engine 1 is transferred to the transmission 2.
2. propeller shirt] via 23, etc. ,
Reference numerals 24 and 25 represent a left driving wheel speed sensor and a right driving wheel speed sensor that detect the rotation speeds of the left driving wheel 20 and the right driving wheel 21, respectively. 26゜27 are the left and right idle wheels that rotate as the IJ vehicle runs, 28.29 are the left and right wheels, respectively: i
e represents the wheel speed sensor.

Note that these sensors 24, 25, 28, and 29 are composed of gears and electromagnetic pickups.

Further, 30 indicates an electronic control circuit.

Assuming that the electronic control circuit 30 is configured using a microcomputer, and proceeding with the explanation, the electronic control circuit 30 is configured using a microcomputer.
The configuration of 0 can be represented as shown in FIG. In the figure, 31 inputs and calculates the data detected by each of the above-mentioned sensors according to a control program, and drives the DC motor 11.
A central processing unit (CPU) 32 is a read-only memory (R) that stores data such as the control program and maps.
OM), 33 is a random access memory (RAM) into which data from each of the above sensors and data necessary for arithmetic control are temporarily read and written, 34 is a waveform shaping circuit and output signals of each sensor are selectively output to the CPU 31 An input section 35 is equipped with a multiplexer etc. to connect the DC motor 11 to the CPU 3.
An output section 36 includes a drive circuit that drives according to a control signal from the CPU 31.i. A path line 37 connects each element such as the ROM 32, an input section 34, and an output section 35 and serves as a path for various data. Numeral 37 represents a power supply circuit that supplies power to each of the above sections.

Next, the operation of this electronic control circuit 30 will be briefly explained. Receives various detection signals from the left driving wheel speed sensor 24, right driving wheel speed sensor 25, left free wheel speed sensor 28, right free wheel speed sensor 29, etc., and maximizes acceleration without causing acceleration slip when accelerating the vehicle. Slip control is performed in which a drive signal is output to the DC motor 11 that adjusts the opening degree of the auxiliary throttle valve 10 to suppress and control the engine output so that the opening degree of the sub-throttle valve 10 is adjusted.

Further, as is well known, the CPU 31 inputs data on the intake air amount detected by the air 70 meter 3 and the engine speed detected by a rotation angle sensor (not shown) through the input unit 34, and calculates basic information from these data. Calculate the fuel injection amount. And this basic fuel injection! ) ffi is corrected by the residual oxygen concentration in the exhaust gas detected by an oxygen sensor (not shown), and the actual fuel injection amount is calculated. Then, the fuel injection valve 4 is controlled based on this actual fuel injection amount, and fuel injection, that is, fuel supply, is performed in accordance with the operating state of the engine.

Similarly, the optimal ignition timing is calculated based on the engine speed, intake air amount, etc., using a data map in the ROM 32, and based on this, an ignition timing signal is sent to an igniter (not shown), and the engine speed Ignition timing control is performed according to the operating conditions of the engine.

Next, the acceleration slip control executed by the electronic control circuit 30 configured as described above will be explained with reference to the main routine flowchart shown in FIG. First, to explain the outline of the processing, there are three main types of processing as follows. That is, as shown by the arrow in the figure, this is a process for maintaining the opening degree of the sub throttle valve 10, that is, a process that is performed when the driving wheel acceleration is positive and smaller than a predetermined positive value.

■ A closing control process for the sub-throttle valve 10, that is, a process performed when the driving wheel acceleration is larger than a positive predetermined value,
This reduces engine output.

■Close control of sub-throttle valve 10 11] process, i.e.
This process is performed when the driving wheel acceleration is negative and increases the engine output to slow down the drop in the driving wheel speed.

These processes are performed by determining the driving wheel acceleration, but since the driving wheel acceleration repeats positive and negative, ■→■→■
The process →■ is executed as one cycle. Next, these processes will be explained in detail based on FIG. 4.5.

Process <a> ■ First, in step 101, the DC motor 11 is driven so as to fully open the sub-throttle valve 10.

Although the sub-throttle valve 10 is always fully open at the end of control I, this is a process to ensure that it is fully open at the start of the main routine. Then step 102
Now, whether the main throttle sensor 13 is on or not.
That is, it is determined whether the vehicle is idling or accelerating. rYEsJ, that is, if it is determined to be idling,
Return to step 101. Here, the process is being accelerated, so
It is determined that it is rNOJ, and the process proceeds to step 103, where:
Average value of left and right idle wheel speed ■ωF, idle wheel acceleration 9ωF
, left driving wheel speed VωRL, right driving wheel speed VωRR, right driving wheel acceleration 9ωRL, right driving wheel acceleration 9ωRR, main throttle opening θH1, and sub-throttle opening θS.

Next, in step 104, the idle wheel speed VωF (considered as the vehicle speed) is adjusted to the set control end vehicle speed VMAX1, for example, 1.
It is determined whether or not it is smaller than 00KIll/H. “NO
”, the process returns to step 101. Here, since it is smaller than rYEsJ, that is, 100 Kl/H, the process proceeds to step 105. In this step, it is determined whether the right idle wheel speed ωRR is greater than the right driving wheel acceleration 9ωRL. That is, it is determined which of the left and right driving wheel accelerations has a larger slip. If it is determined that rYEsJ, then in step 106 the right drive wheel acceleration 9ωRR is set as the drive wheel acceleration ωR. If it is determined that rNOJ, the left driving wheel acceleration 9 is similarly determined in step 107.
ωRL is set as ωR. In this way, a drive wheel with a large slip is selected, and slip control is performed based on this selection.

Next, in step 108, it is determined whether the driving wheel acceleration, VωR, is greater than a predetermined value of 61A. In other words, it is determined whether or not the vehicle is in a state immediately before slipping. Here, rNOJ is determined and the process jumps to step 109. That is, no slip has occurred, and processing is performed to hold the sub throttle valve 10. In step 109, it is determined whether the driving wheel acceleration angle ωR is negative or not. Here, since it is accelerating,
If the determination is NO, the process jumps to step 110, holds the sub-throttle opening degree θS, and returns to step 102, where the same process is performed.

(b) Processing of ■ In the loop processing of ■, the driving wheel acceleration increases as shown in FIG. 5(a). Therefore, since the drive wheel acceleration annoyance ωR exceeds VA, step 10 of the above loop processing
At step 8, it is determined to be rYEsJ, and the process jumps to step 111. Here, as shown in Fig. 6, the opening degree θCLO8E during the closing control of the sub-throttle valve 13 is 2·Vω.
Set F. However, K2 is a constant. This θCLO
The reason why the 3E value is changed according to the idle wheel speed VωF as the vehicle speed is mainly to smooth the convergence of the driving wheel speed ■ωR. More specifically, for example, as shown in FIG. 5(A), when the control is activated from the starting state, the rear wheel slip ΔVω, which indicates the amount of slip, decreases as the control progresses.

The vehicle speed also increases. In this case, if the 01 throttle valve 10 is controlled to a constant value, for example, fully open, as the vehicle speed increases, the control frequency of ωR increases, which may lead to an uncomfortable driving feeling. So θ
By controlling the value of CLO8E according to the vehicle speed, the above-mentioned phenomenon can be avoided and smooth running conditions can be obtained.

The process then proceeds to step 112, where the sub-throttle opening degree is reduced to θCLO8E. Therefore, Figure 5 (c)
As shown in FIG. 2, the sub-throttle valve 10 is driven by the DC motor 11 from fully open to fully open, and the fully open state continues to be maintained.

Next, in step 113, it is determined whether the driving wheel acceleration increment ωR is larger than the maximum value of the driving wheel acceleration up to the previous time ωRMAX. Here, since the driving wheel acceleration ωR has not reached the maximum value and is increasing, it is determined as “YESJ” and step 1
The process jumps to step 14, where the driving wheel acceleration ωR of step 113 is set as the maximum planting ωRMΔX of the driving wheel acceleration, and if the determination is "NO", the process jumps to step 11.
4 and return to step 102. In other words, steps 113 and 114 are processes for detecting x to the maximum upright ωRM of the driving wheel acceleration.

(c) Processing of ■ When the loop processing of ■ is performed, the process is completed! The acceleration ωR decreases after reaching the maximum value of the driving wheel acceleration and becomes smaller than the predetermined value VA, so it is determined as rNOJ in step 108, and the process jumps to step 109, where the driving wheel acceleration is positive, so step 110 As described above, the sub throttle valve 10 is held in the all 1 state.

(d) Processing of ■ By the processing of ■, the driving wheel acceleration summer ωR decreases, and this time, in step 109, it is determined that rYEsJ, and the process jumps to step 115, where the driving wheel speed ■ωR and the idle wheel speed ■
The difference from ωF is set as ΔVω. Then step 1
16r-, the opening speed VM of the sub-throttle valve 10 is set by the following equation as shown in FIG.

RMAX was determined in step 114 (directly, KlB is a constant).

This is because the driving wheel acceleration decreases and VωR-
This is to reduce the shock when VωF occurs.

This shock is applied to the road surface when the tire grips the road surface.
This occurs because the friction coefficient increases and the driving force increases. In addition, the reason why VM was changed by ΔVω is that the degree of decrease in driving wheel speed is different depending on small slip and excessive slip. is changed by ΔVω.

The reason why ωRMAX is also changed is that, as shown in Fig. 8, on the same high friction coefficient road (high μ road), the time difference TH until the driving wheel acceleration ωR becomes equal to ■ωF due to the above-mentioned ΔVω. However, there is an additional time difference TL between the high μ road and the low friction coefficient road (low μ road). Therefore, V(1)R, which has a correlation with the road surface friction coefficient,
By detecting MAX, the above-mentioned time difference T1- is eliminated. That is, as shown in Fig. 7, zoωR is
When M△X is small, the opening speed VM is fast, and conversely, the opening speed VM is low
When 9ωRMAX is large, such as on a road, the opening speed VM is controlled slowly to smooth the decrease in slip and eliminate the above-mentioned shock. The reason why the auxiliary throttle valve 10 begins to open at the time when ωR<O is that it is attempted to open the sub-throttle valve 10 early in consideration of engine 1-lux rise (responsiveness) and delay in the drive system, especially in the automatic transmission. It is.

Next, in step 117, the auxiliary throttle valve 10 is adjusted to the opening speed VM up to the opening degree θ) of the main throttle valve.
Open it with it. In the following step 118, since the opening of the auxiliary throttle valve 10 has been completed, the maximum value of the drive wheel acceleration is set to zero and initialized.

Then, in step 119, the elapsed time TS during which the opening degree θS of the throttle valve 10 is maintained at θH reaches a predetermined value TO.
11 determine whether or not it is greater than P.

Since it is determined to be rNOJ, the process returns to step 102 and loop processing is performed.

In this way, when the sub-throttle valve 10 is gradually opened and the engine output increases, the driving wheel acceleration increases,
At step 10, rNOJ is determined, and the first process (2) starts again. In this way, (a), (b), (c), (
As the process d) is repeated, the driving wheel acceleration gradually converges, and the nine driving wheel speeds also converge.

Therefore, the drive wheel acceleration does not exceed the predetermined level VA, and it is determined that the drive wheel acceleration has been suppressed, and the processes of (1) and (2) are repeated. Therefore, in step 119, rY
EsJ is determined, and the process returns to 101, and the sub-throttle valve 10 is fully opened.
Loop 51 of 105 → 106 → 107 → 108 → 109 → 110! The auxiliary throttle valve 10 is held fully open as shown in FIG. 5(c).

In addition, in this embodiment, the left and right drive wheel speed sensor 24.2
5 corresponds to drive wheel rotation state detection means, and electronic control circuit 3
0 corresponds to the control means, the left idle wheel speed sensor 28 and the right idle wheel speed sensor 29 correspond to the vehicle speed detection means, and the DC motor 11 and the series of processes of the control program shown in FIG. 4 correspond to the opening/closing control section. .

As explained above, according to this embodiment, by using the sub-throttle valve 10 for engine output control, the engine intake air amount can be adjusted to vIIII, so that the engine output control range can be widened while keeping the air-fuel ratio at the optimum value. . Further, even if the sub throttle valve 1Q fails, the main throttle valve 8 can operate normally.

Furthermore, since the drive wheel acceleration is used to detect the slip of the drive wheels, the detection can be speeded up. Further, since the closing control of the sub-throttle valve 1o is performed from the point where the driving wheel acceleration is negative, accurate control can be performed in consideration of torque rise and drive system delay.

Furthermore, the opening speed vM is determined by Δ■ω indicating the degree of slip.
Since the driving wheel speed VωR gradually decreases and the driving wheel speed ■ωR becomes equal to the rt rear wheel speed VωF, that is, when the tires grip the road surface, the shock can be reduced.

Since the opening speed VM is slowed by the maximum driving wheel acceleration ωRMAX, the driving wheel speed ωR decreases more slowly on a low μ road, thereby reducing the above-mentioned shock.

Therefore, good slip suppression can be achieved on both high μ roads and low μ roads.

Furthermore, in the process (2), the opening degree θCLO8E of the sub-throttle valve 1Q is increased as the vehicle speed increases.
The control frequency of the driving wheel speed ■ωR changes smoothly and the convergence time becomes slow. Therefore, the running becomes smoother, the running feeling becomes better, and the durability of the vehicle is improved.

Although specific embodiments of the present invention have been described above, the present invention is not limited to such embodiments, and includes various types of actual tNg within the scope of the claims. For example, the present invention can also be applied to a front engine front drive (FF system).

[Effects of the Invention 1 The present invention has the following excellent effects. In other words, ■Since the sub-throttle valve is provided upstream or downstream of the main throttle valve, the amount of engine intake air can be controlled.
The engine output control range can be widened while maintaining the air-fuel ratio at the optimum value.

■Even if the sub-throttle valve fails, normal operation is possible with the main throttle valve, so the vehicle can run safely.

■Of the opening/closing control performed in the opening/closing υ1101 section, closing 1Il
Since lIlfII is controlled according to the vehicle speed, the drive wheel speed converges smoothly, resulting in smooth running, a good running feeling, and improved vehicle durability.

[Brief explanation of drawings]

Fig. 1 is a basic configuration diagram, Fig. 2 is a schematic configuration diagram of an embodiment of the present invention, Fig. 3 is a block diagram of an electronic control circuit, and Fig. 4 is a flowchart V showing control program contents of the electronic control circuit.
- Fig. 5 is a timing chart of driving wheel speed, driving wheel acceleration, and throttle opening, and Fig. 6 is a timing chart of driving wheel speed, driving wheel acceleration, and throttle opening.Fig. A graph showing the relationship between the product ΔVω・tsuωRMAX and 9ωRMAX, Fig. 7 is a graph showing the relationship between the opening degree θCLO8E during closing control and the idle wheel speed ■ωF, and Fig. 8 shows the relationship between the high μ road and the low μ road. The timing charts of the driving wheel speed and the driving wheel acceleration are respectively shown in FIG. 8... Main throttle valve 9... Accelerator pedal 1o... Sub throttle valve 11... DC motor 12... Main throttle sensor 13... Sub throttle sensor 24... Left drive wheel speed sensor 25 ...Right drive wheel speed sensor 30...Electronic control circuit

Claims (1)

[Scope of Claims] Drive wheel rotation state detection means for detecting the rotation state of the drive wheels; An acceleration slip control device for a vehicle comprising: a control means for suppressing transmitted engine torque; A sub-throttle valve provided upstream or downstream of the valve, and an opening/closing control section for controlling opening and closing of the sub-throttle valve, and of the opening/closing control, the closing control is detected by the vehicle speed detection means. An acceleration slip control device for a vehicle, characterized in that it is configured to perform control according to vehicle speed.