JP2986640B2 - Vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vehicle, and more particularly to a control device for a vehicle which can appropriately cope with a failure of a throttle valve of a throttle control system.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a configuration diagram illustrating a conventional vehicle control device disclosed in Japanese Unexamined Patent Application Publication No. 2000-205,036. In the figure, reference numeral 101 denotes an engine, and 102 denotes a throttle valve for adjusting an intake air amount of the engine 101, which is provided in an intake pipe 103. 104 is a throttle valve 1
02 is a throttle actuator that drives a DC motor 02 and includes a DC motor, a stepping motor, and the like.

[0005] 105 is a throttle actuator 104.
A return spring for operating the throttle valve 102 to the closing side; a throttle position sensor (TPS) 107 as a throttle opening sensor for detecting the opening of the throttle valve 102; A pedal 109, an accelerator position sensor (APS) as an accelerator opening sensor for detecting the opening of the accelerator pedal 108, 110 a rotation speed sensor for detecting the rotation speed of the engine 101, 11
An air flow sensor (AF) 1 measures an intake air amount.
S), 112 is an injector for injecting fuel, 113
Is a spark plug, and 114 is a control unit.

Next, the operation of the vehicle control device will be described with reference to FIG.
This will be described according to the flowchart of FIG. The calculation and the condition determination described below are performed by a microcomputer in the control unit 114. First, in step S1, the value of the accelerator opening sensor 109 whose output changes in conjunction with the accelerator pedal 108 is read, and in step S2, the target throttle opening θs is calculated. In this calculation, how the target throttle opening θs is made to correspond to the accelerator opening α is set in advance, and is obtained from a predetermined function and a corresponding correction.

The accelerator opening α and the target throttle opening θs
Is different depending on how to set the power performance of the vehicle with respect to the accelerator opening α, but generally has characteristics as shown in FIG. Characteristic curve a of FIG.
Shows the case where the target throttle opening θs is changed in proportion to the accelerator opening α, and the characteristic curve b shows that the change of the target throttle opening θs in the low opening region of the accelerator opening α is gradual. I have. This is to improve the phenomenon that a large change in the amount of intake air at the time of starting or running at low speed causes a shock or makes it difficult to make fine adjustments.

On the other hand, as shown in FIG.
The output torque of No. 1 is not uniform with respect to the engine speed, and decreases in a low speed range or a high speed range. Therefore, if the characteristic curve b is corrected using the opening correction coefficient Ne in FIG. 11, the feeling of insufficient output torque in the engine speed region can be improved. The control characteristic of the target throttle opening θs with respect to the accelerator opening α is only an example, and may differ depending on the characteristics (smoothness, sportiness, etc.) of the vehicle and the engine performance.

Returning to FIG. 9, in step S3, the actual throttle opening θr is read from the throttle opening sensor 107, and in step S4, a deviation e between the target throttle opening θs and the actual throttle opening θr is calculated. If θs is smaller than θs, the throttle actuator 104 is driven to the open side in accordance with the deviation e in step S5, and if θr is larger than θs, the throttle actuator 104 is driven to the closed side in step S6 in accordance with the deviation e.

As described above, by opening and closing the throttle valve 102 using the throttle actuator 104, control with a high degree of freedom becomes possible. If a vehicle speed signal is fed back, the function of a constant speed traveling device can be added. it can. However, when the throttle valve 102 is electrically controlled, unlike the conventional case where the throttle valve 102 is opened and closed in a mechanically linked manner by the accelerator pedal 108, the throttle valve 102 becomes inoperative due to a failure of the throttle actuator 104, the control unit 114, and the like. Fail-safe is important because it can lead to runaway.

Next, the operation at the time of failure will be described with reference to the flowchart of FIG. In step S11, a target intake air amount at is obtained by calculation based on the accelerator opening and the engine speed, and in step S12, the opening of the throttle valve 102 is controlled so as to obtain the target intake air amount at.
Subsequently, in step S13, the actual intake air amount ar is obtained from the output of the airflow sensor 111, and in step S14, the deviation | at-ar | between the target intake air amount at and the actual intake air amount ar.
Is greater than or equal to a predetermined value K. | At-ar |
If not> K, the disconnection of the throttle opening sensor 107 is detected in step S18, for example, based on the sensor output voltage.

If it is determined in step S14 that | at-ar |> K is not satisfied and the throttle opening sensor 107 is not disconnected in step S18, normal processing is performed in step S19. That is, the number of fuel injection cylinders is assumed to be all injections, and the fuel injection amount and the ignition timing are determined by the airflow sensor 111 and the rotation speed sensor 110.
Is controlled by a known method from the output value of On the other hand, step S
If | at−ar |> K at 14 or if the throttle opening sensor 107 is disconnected in step S18, the accelerator opening α is read in step S15, and the accelerator opening α is read in steps S16 and S17. Accordingly, the number of injection cylinders N and the ignition timing IG are determined and controlled. As described above, the minimum traveling is possible even when the throttle control system is abnormal.

[0011]

Since the conventional vehicle control device is configured as described above, the vehicle can run when the throttle valve is stuck in the open state to a certain extent or more. In the case where it is fixed, there is a problem that the running is impossible due to insufficient output. On the other hand, when the fuel is stuck on the fully open side, even if the number of cylinders for injecting the fuel is reduced, the engine output is not squeezed and is dangerous.

The present invention has been made in order to solve such a problem, and it is possible to drive safely even when the throttle valve is fully closed and stuck due to excessive output even when the throttle valve is fully opened and stuck. It is an object of the present invention to provide a vehicular control device capable of driving with a margin without any problem.

[0013]

A vehicle control device according to the present invention includes an accelerator opening sensor for detecting an accelerator opening, a throttle actuator for adjusting an opening of a throttle valve according to the accelerator opening, and Above throttle valve
A throttle opening sensor that detects the opening of the engine, a bypass control valve that is provided in an intake passage that bypasses the throttle valve, and that is controlled in opening according to the operating state of the engine, and that supplies fuel according to the intake air amount to the engine. an injector for adjusting, and an automatic transmission that switches the gear position by the accelerator opening and the vehicle speed, the abnormality detecting means for detecting a control abnormality of the throttle actuator, the abnormality detection
The throttle opening and the accelerator
Bypass that controls the opening of the bypass control valve according to the cell opening
The difference between the path control valve opening control means and the abnormality detection means
It responds to the throttle opening and the accelerator opening during normal detection.
Timing control method that controls the ignition timing control area separately
And the slot when the abnormality is detected by the abnormality detection means.
Of the automatic transmission according to the throttle opening and the accelerator opening.
And a shift speed control means for controlling the shift speed control region separately .

[0014]

According to the present invention, when a control abnormality of the throttle actuator is detected, the number of fuel injection cylinders,
Since the ignition timing, the degree of opening of the bypass control valve, and the gear position of the automatic transmission are controlled, the minimum travel is possible regardless of the position where the throttle valve is stuck.

[0015]

【Example】

Embodiment 1 FIG. FIG. 1 shows an embodiment of a vehicle control device according to the present invention. In FIG. 1, portions corresponding to those in FIG. 8 are denoted by the same reference numerals, and detailed description thereof will be omitted.
In the figure, 114A is a control unit, 115 is a load sensor indicating the load state of engine accessories such as an air conditioner, power steering, electric load, etc., 116 is a bypass connected to the intake pipe 103 by bypassing the throttle valve 102, 1
Reference numeral 17 denotes a bypass control valve for controlling the amount of air passing through the bypass path 116, reference numeral 118 denotes an automatic transmission, and reference numeral 119 denotes a hydraulic solenoid for controlling the speed of the automatic transmission 118. This example is configured as described above, and the rest is configured similarly to the example of FIG.

Next, the operation of this embodiment will be described. The control of the throttle actuator 104 is performed in the same manner as in the prior art as shown in FIG.
Is performed according to the flowchart of FIG. In addition, intake pipe 1
Conventionally, a bypass passage 116 is provided in the engine 03, and a bypass control valve 117 is provided in the bypass passage 116 to control the idling speed. The degree of opening of the bypass control valve 117 is controlled in an open loop according to the steering, electric load, etc., and feedback is performed so that the engine speed becomes a predetermined value when the throttle valve 102 is fully closed (accelerator off). Control.

FIG. 2 shows a throttle actuator 104.
6 is a flowchart showing an operation when an abnormality occurs in the control of FIG. In step S20, a deviation β between the actual throttle opening θr and the target throttle opening θs is determined. If the control system of the throttle actuator 104 is normal,
Since a difference exceeding a certain level does not occur, abnormality detection can be performed.

In a step S21, it is determined whether or not the deviation β is larger than a predetermined value β1.
Normal processing of 8 to S32, if larger, step S22
To S27. If β> β1 is not established, the throttle actuator 104 is controlled in the step S28 as shown in the flowchart of FIG.
In step S32, the fuel, ignition timing, idle speed, and transmission are respectively controlled by a known method as in the related art.

On the other hand, if β> β1 and an abnormality is detected, then in step S22 the throttle actuator 1
The driving of the throttle valve 102 is stopped, and the throttle valve 102 is returned to the fully closed position by the return spring 106 which improperly closes the throttle valve 102 in the closing direction. However, depending on the degree of occurrence of the abnormality, the throttle valve 102 may be stuck at the middle or fully open position. Therefore, in step S23, the accelerator opening α is read, and in step S24, the number N of cylinders for injecting fuel is controlled according to the accelerator opening α and the actual throttle opening θr parameter to control the engine output according to the driver's will.

FIG. 3 shows an example of the relationship between the accelerator opening α, the actual throttle opening θr, and the number N of cylinders in the case of a four-cylinder engine. As shown, for example, the actual throttle opening θ
When r is stuck near the fully open position, the number of injection cylinders N becomes 1 → 2 → 3 and the engine output increases as the accelerator opening α changes from the fully closed state to the fully opened state. Similarly, near the middle, N becomes 2 → 3 → 4. However, in the vicinity of the fully closed state, even if all cylinders are injected, the engine output is small, and the engine output cannot be effectively controlled only with the number of injection cylinders N to avoid engine stall.

Therefore, in step S25, the engine output is controlled by driving the bypass control valve 117 using the actual throttle opening .theta.r and the accelerator opening .alpha. As parameters, for example, in the relationship shown in FIG. As shown in the figure, when the actual throttle opening θr is close to the fully closed position, the engine output is controlled by controlling the opening of the bypass control valve 117 to 0% to 100% according to the accelerator opening α. When θr is larger than a certain value, the opening degree of the bypass control valve 117 is 0%.
Is fine.

In step S26, the actual throttle opening θr
And the accelerator opening α as a parameter, the ignition timing IG is controlled by dividing the ignition timing into a retarded region and a normal advanced region as shown in FIG. If the actual throttle opening [theta] r is stuck at a large opening, the engine output is excessive and the output is retarded to reduce the output . This retarded region corresponds to the bypass control valve 117 shown in FIG.
Corresponds to a region where the opening degree is 0%, or a region where the number N of injection cylinders in FIG. In the normal advance range, the ignition timing is controlled by a normal ignition timing determined by a known method using the engine speed Ne and the charging efficiency CE as parameters.

In step S27, the gear stage GEAR is similarly divided into two control regions (region I and region II) as shown in FIG. 6 based on the actual throttle opening θr and the accelerator opening α. In the region I, for example, the third speed is fixed so that the vehicle runs at a low engine speed. Vehicle speed mainly, than the normal shift position, as shown in FIG. 7 in the region II is a control of the engine output at a flow rate of the bypass control valve 117
Shifts on the higher side to improve acceleration.

Embodiment 2 FIG. In the above embodiment,
An abnormality in the control of the throttle actuator 104 is determined based on the magnitude of the deviation β between the target throttle opening θs and the actual throttle opening θr, but the intake air amount of the engine 101 (output of the air flow sensor 111) and the accelerator opening α or the target An abnormality may be determined based on the relationship with the throttle opening θs, or another sensor may be added. In the control of the number N of injection cylinders, a shock occurs when the number of cylinders N is switched. Therefore, it is effective to provide a dead zone (hysteresis) in the switching determination value or to prohibit the switching for a predetermined time after the switching. Further, in an automatic transmission having a lock-up mechanism, the switching shock can be absorbed by the torque converter by prohibiting the lock-up during the execution of the abnormality processing.

In the automatic transmission control, in the shift speed and the shift hydraulic pressure control in which the throttle opening .theta.r is used as an engine output parameter in a normal state, during abnormal processing, the actual throttle opening .theta.r is replaced with .theta.r + g (.theta.B). Is used, the accuracy of the engine output parameter is maintained, and the controllability is improved. Here, θB is a bypass control valve opening, and g is a function set in advance. Further, a control unit for performing throttle actuator control, fuel control, ignition control, bypass control valve control, and gear position control of the automatic transmission may be separately provided, and information may be exchanged through a signal line.

Embodiment 3 FIG. When controlling the number N of the injection cylinders, the cylinders for which injection is stopped may be replaced at predetermined time intervals in consideration of the ignition interval to keep the heat balance of the engine 101 uniform and prevent the engine 101 from deteriorating.

Embodiment 4 FIG. In a case where the throttle valve 202 is fixed in a state of being opened to a certain degree or more and the engine output is controlled by controlling the number N of injection cylinders, even if the engine overspeed fuel cut rotation speed is set lower than the normal value. Good. Further, the cut rotation speed may be switched depending on the range of the transmission, the load state of the auxiliary machine, or the warm-up state of the engine.

Embodiment 5 FIG. During the execution of the abnormality processing, a failure indicator lamp attached to the driver's seat may be turned on to warn the driver of this.

[0029]

As described above, according to the present invention, the accelerator opening sensor for detecting the accelerator opening, the throttle actuator for adjusting the opening of the throttle valve according to the accelerator opening, and the throttle valve Detect opening
A throttle opening sensor, provided in an intake passage bypassing the throttle valve, and a bypass control valve which is opening control according to the operating state of the engine, an injector for adjusting the fuel according to the intake air amount of the Enshinhe, the
An automatic transmission that switches the gear position by the accelerator opening and the vehicle speed, the abnormality detecting means for detecting a control abnormality of the throttle actuator abnormal detection by the abnormality detecting means
According to the throttle opening and the accelerator opening
Bypass control valve opening control that controls the opening of the bypass control valve
Control means and the above-mentioned scan when an abnormality is detected by the abnormality detection means.
Ignition timing control according to the throttle opening and the accelerator opening
An ignition timing control means for controlling the region separately;
The throttle opening when the abnormality is detected by the
The gear position control area of the automatic transmission is changed according to the
When a control abnormality of the throttle actuator is detected, the number of fuel injection cylinders, ignition timing, and bypass control valve opening are determined by using the accelerator opening as a parameter according to the abnormality level. In addition, since the gear position of the automatic transmission is controlled, the vehicle can travel at a minimum even if the throttle valve is stuck at any position, and the safety of the vehicle can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a vehicle control device according to the present invention.

FIG. 2 is a flowchart illustrating an abnormality determination and a subsequent processing operation of the embodiment of the vehicle control device according to the present invention;

FIG. 3 is a diagram showing the relationship between the number of fuel injection cylinders using an accelerator opening and a throttle opening as parameters.

FIG. 4 is a diagram illustrating a relationship between an opening degree of a bypass control valve using an accelerator opening and a throttle opening as parameters.

FIG. 5 is a relationship diagram of an ignition timing control region using an accelerator opening and a throttle opening as parameters.

FIG. 6 is a relationship diagram of an automatic transmission control region using an accelerator opening and a throttle opening as parameters.

FIG. 7 is a diagram showing a relationship between shift positions during normal operation and during abnormal processing.

FIG. 8 is a configuration diagram illustrating an example of a conventional vehicle control device.

FIG. 9 is a flowchart showing a control operation of a throttle actuator.

FIG. 10 is a relationship diagram between an accelerator opening and a target throttle opening.

FIG. 11 is a relationship diagram of an engine speed, an engine torque, and an opening degree correction coefficient.

FIG. 12 is a flowchart showing the abnormality determination of the conventional device and the subsequent processing operation.

[Explanation of symbols]

 Reference Signs List 101 engine 102 throttle valve 103 intake pipe 104 throttle actuator 107 throttle opening sensor 108 accelerator pedal 109 accelerator opening sensor 112 injector 113 ignition plug 114A control unit 116 bypass passage 117 bypass control valve 118 automatic transmission 119 hydraulic solenoid

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16H 61/12 F02P 5/15 L // F16H 59:18 59:24

Claims (1)

(57) [Claims] 1. An accelerator opening sensor for detecting an accelerator opening, a throttle actuator for adjusting an opening of a throttle valve according to the accelerator opening, and a throttle opening sensor for detecting an opening of the throttle valve.
And an intake passage bypassing the throttle valve,
A bypass control valve whose degree of opening is controlled in accordance with the operating state of the engine; an injector that adjusts fuel in accordance with the amount of intake air to the engine; an automatic transmission that switches gears based on the degree of accelerator opening and vehicle speed; Abnormality detection means for detecting a control abnormality of the throttle, and opening of the throttle when abnormality is detected by the abnormality detection means.
And the opening of the bypass control valve according to the accelerator opening
A bypass control valve opening control means for controlling the throttle opening when the abnormality is detected by the abnormality detecting means;
The ignition timing control area is divided according to the degree and the accelerator opening.
Ignition timing control means for controlling the throttle opening when the abnormality is detected by the abnormality detection means.
Speed of the automatic transmission according to the degree and the accelerator opening.
A control device for a vehicle, comprising: a shift speed control means for controlling the control region separately .