JPH01305150A - Throttle valve control device - Google Patents

Abstract

PURPOSE:To enhance the reliability of dual control systems composed of two throttle valves, two electrical actuators and two control means by controlling the throttle valves in accordance with an accelerator opening degree signal alone when an abnormality occurs in one of the control systems. CONSTITUTION:Two throttle valves 1, 2 are arranged in series in an intake-air pipe 11 of an internal combustion engine 9, and are controlled by means of two motors 3, 4, independently from each other, and two angle sensors 5, 6 detect the opening degrees of the throttle valves, and deliver signals to an electronic control device 8 together with signals from an accelerator opening degree sensor 7 and a throttle valve opening degree instruction signal output device 10. The electronic control device 8 delivers control signals in accordance with the received signals to the motors 3, 4. In this arrangement, if an abnormally occurs in one of two control systems, these throttle valves 1, 2 are controlled in accordance with a signal from the accelerator opening degree signal 7.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a throttle valve control device, and particularly to improving the reliability thereof.

[Conventional technology]

The so-called linkless throttle, which eliminates the conventional link mechanism between the throttle valve and the accelerator pedal, has good controllability for constant speed cruise control and traction control as other throttle valve controls, independent of the amount of depression of the accelerator pedal. , is known to be superior in various respects. For this reason, many proposals regarding linkless throttles have been made. Among them, for example, JP-A-59-19693
The throttle valve disclosed in Japanese Patent No. 8 is comprised of a first throttle valve that is driven via a link mechanism in conjunction with an accelerator pedal, and a second throttle valve that is driven by an electronically controlled actuator.

In the above configuration, even if the electronically controlled actuator fails and the second throttle valve opens against the driver's intention, the engine speed will rapidly increase because the driver closes the first throttle valve. There's nothing to do. Therefore, it can be said that this configuration is extremely excellent in terms of safety measures in the event of an abnormality.

[Problem to be solved by the invention]

However, according to the above configuration, the first throttle valve requires a link mechanism for interlocking with the accelerator pedal. Therefore, there is a problem that the structure becomes complicated due to the provision of the link mechanism.

On the other hand, in order to simplify the configuration, a system has also been proposed in which the intake air amount of an internal combustion engine is controlled using only one linkless throttle valve. With such a configuration, constant speed driving control and traction control control as other controls can also be performed with a simple configuration. However, it is not possible to completely guarantee bank-up in the event of motor failure or safety measures, resulting in lower reliability.

The present invention has been made in view of the above points, and is a throttle valve control device that is capable of executing additional controls such as constant speed running control and traction control control with a simple configuration, and has improved reliability. The purpose is to provide

[Means to solve the problem]

In order to achieve the above object, the throttle valve control device according to the present invention has first and second throttle valves installed in series in the middle of an intake pipe of an internal combustion engine, and the first and second throttle valves, as shown in FIG. first and second electric actuators that independently drive the second throttle valve; an accelerator opening sensor that outputs an accelerator opening signal according to the amount of depression of the accelerator pedal; , a throttle valve opening command output means for outputting an opening command signal for the first and second throttle valves; an accelerator opening signal output by the accelerator opening sensor; and an accelerator opening command output means for outputting the throttle valve opening command signal. first and second throttle valves that output control signals to the first and second electric actuators based on the opening command signal to separately control the openings of the first and second throttle valves, respectively; A monitoring means for monitoring the operating states of two systems constituted by a control means, the first and second throttle valves, an electric actuator, and the control means and detecting an abnormal state; When an abnormal state is detected in the operating state of one of the systems, the control based on the opening command signal is prohibited, and the control is performed based only on the accelerator opening signal.
and prohibition control means for controlling the first and second throttle openings.

[Effect]

According to the above configuration, the first and second control means independently control the opening degrees of the first and second throttle valves. Therefore, even if an abnormal condition occurs in one of the systems and the throttle valve of that system becomes abnormally open, the throttle valve of the other normal system will maintain the same amount of intake air as before the abnormality occurred. Since the engine speed is supplied to the engine, a sudden increase in engine speed can be suppressed.

Furthermore, when the monitoring means detects the occurrence of an abnormal state in either system, the prohibition control means controls the opening of the throttle valve based on the opening command signal output by the throttle valve opening command output means. In addition, in an unstable state where an abnormality occurs in one of the systems, the opening of the throttle valve is controlled based on the amount of accelerator pedal depression, which directly reflects the driver's intention to accelerate or decelerate.

Thereby, reliability of the throttle valve control device can be further improved.

〔Example〕

An embodiment of the present invention will be described based on the drawings.

In FIG. 1, a first throttle valve 1 and a second throttle valve 2 are arranged in series in the middle of an intake pipe 11 of an internal combustion engine 9. As shown in FIG. First and second motors 3, 4 mounted on the outside of the intake pipe 11 independently drive the first and second throttle valves 1.2, respectively. Furthermore, first and second angle sensors 5 and 6 are attached to the outside of the intake pipe 11 to detect the opening degrees of the first and second throttle valves 1 and 2, respectively, and output them to the electronic control device 8. are doing. The electronic control device 8 receives a signal from the accelerator opening sensor 7, a signal from the throttle valve opening command signal output device 10, and a first
and signals from the second angle sensors 5 and 6, and control signals corresponding to these signals are applied to the first and second motors 3.
．． Output to 4.

Here, the throttle valve opening command signal output device 10 serving as the throttle valve opening command output means is, for example, a constant speed cruise control device or a traction control control device, and is used to command the throttle valve opening from the outside. .

FIG. 2 shows a block diagram of the electronic control device 8.

The electronic control device 8 includes an input section 20.27 that performs signal processing so that an input signal (for example, an accelerator opening signal from the accelerator opening sensor 7) can be processed by the CPU 21.28, and an input section 20.27 that performs signal processing so that an input signal (for example, an accelerator opening signal from the accelerator opening sensor 7) can be processed by the CPU 21.28. CPU that calculates the opening degree
21, 28, an oscillator 24.31 that provides a reference clock to the CPU 21.2B, and a watchdog (W/D) that determines whether the CPU 21.2B is operating normally.
A circuit 34.35, a ROM 22.29 for storing required data such as control data, a RAM 23.30 for storing calculation results etc. by the CPUs 21 and 28, and a CPU 21,
The drive unit 26 and 33 output drive signals to the motors 3 and 4 based on the calculation result by the drive unit 2B. Here, C.P.
U21 and U28 correspond to the first and second control means. The electronic control device 8 includes two of the above-mentioned components corresponding to the first and second motors 3 and 4, and controls the first and second motors 3 and 4 independently.

Furthermore, there are two independent power supply circuits 25° 32 inside the electronic control bag W8, which prevents the electronic control device 8 from becoming completely inoperable even if one power cable is disconnected. .

The operation of the above configuration will be explained based on the flowchart of FIG. Note that a subscript a is added to the step number of the flowchart of control performed by the CPU 21, and
A subscript is added to the step number in the flowchart of control performed by U2B.

In steps 10a and 10b, the throttle valve opening command output device 10 determines whether the throttle valve 1.2 is to be controlled according to the accelerator depression amount or according to an external command from the throttle valve opening command signal output device 10. Select by signal.

When an external command is selected in steps 10a and 10b, the process proceeds to steps 20a and 20b, and when an accelerator depression amount is selected, the process proceeds to steps 30a and 30b. In steps 20a and 20b, the throttle valve opening position indicated by the external command is used as a throttle command value, and in steps 30a and 30b, the throttle command value is calculated according to the value output by the accelerator opening sensor 7 indicating the amount of accelerator depression. do.

In steps 40a and 40b, an alive signal (for example, a signal such as A (1010)) is sent to the CPU on the other side to inform that the CPU is normal, and at the same time, an alive signal sent from the other side is received.

In steps 50a and 50b, it is determined whether the alive signal transmitted from the other party's CP tJ in step 40 has been received within a certain period of time. At this time, if the CPU is received within a certain period of time, it is assumed that the other party's CPU is normal, and the process proceeds to steps 60a and 60b. Then, the motors 3 and 4 are driven so that the throttle valve follows the throttle command value calculated in steps 20a and 20b or steps 30a and 30b. On the other hand, if the alive signal is not received within the -. period, it can be assumed that the other party's CPU is not operating normally and the alive signal was not transmitted.

Here, steps 40a, 50a and steps 40b, 5
0b corresponds to the monitoring means.

When one of the CPUs is in an abnormal state as described above, the process proceeds to steps 70a and 70b, and control of the throttle valve in response to an external command by the throttle valve opening command signal output device 10 is prohibited. That is, when an abnormality occurs in one of the CPUs, control by external commands is prohibited to prevent the influence from spreading to other CPUs. Here, steps 70a and 70b correspond to prohibition control means.

In steps 80a and 80b, the driver is warned that an abnormality has occurred on the other party's side.

In steps 90a and 90b, the motors 3 and 4 are driven according to the amount of accelerator depression that reflects the driver's intention to accelerate or decelerate, that is, the output value of the accelerator open sensor 7.

Here, the throttle valve 1.2 is initially set at an opening degree of approximately 45°, which is approximately intermediate between a fully open state and a fully closed state. When an abnormality occurs in the CPUs 21 and 28, the W/D circuit 34 and 35
8 will be reset. As a result, the throttle valves 1 and 2 of the system in which the abnormality has occurred are held in the initial state, so that the normal driving control can be performed using the throttle valves 1 and 2 of the normal system.

FIGS. 4(a), (b), (C), and (d) show what happens when an abnormality occurs in one of the CPUs 28.

The first and second throttle valves 1 depending on the amount of accelerator depression.
．． 2 are independently controlled, and an amount of air corresponding to the opening degree of the throttle valve 1.degree. 2 is sucked into the cylinder of the internal combustion engine. At this time, if an abnormality occurs in the CPU 28 at time tl,
The second throttle valve 2 approaches its initial state (around 45° opening).

However, the intake air amount is limited by the first throttle valve 1, and the engine speed does not increase. At that time, the first and second throttle valves 1.2 were controlled to the same opening position, so even if an abnormality occurred in the second throttle valve 2, the running condition could be maintained exactly as before. I can do it.

In the above embodiment, the first and second throttle valves 1
, 2 are controlled simultaneously and in the same manner. However, for example, when the second throttle valve 2 is kept in a fully open state and an abnormality occurs in the first throttle valve 1,
The second throttle valve 2 may also be driven.

Further, in the above embodiment, the throttle valves 1 and 2 are driven by the motor 3.4, but a configuration may be adopted in which the throttle valves 1 and 2 are driven using a solenoid valve.

Note that in the above embodiment, the CP is activated by the alive signal.
Only abnormalities in U21 and U28 were detected.

However, after a certain period of time after driving the motors 3 and 4 in accordance with the throttle command value, by comparing the opening values of the throttle valves 1 and 2 detected by the angle sensors 5 and 6 with the throttle command value, not only the CPU 21 and 28 , motor 3
, 4 and the drive section 26, 33 of the electronic control device 8, etc. can also be detected. That is, even if the CPU is normal, if there is an abnormality in the motors 3, 4 or the drive unit 26, 33, the throttle command value output by the CPU 21, 28 and the throttle valve 1.
This is because it does not match the opening degree detection value No. 2. In addition, by comparing the opening detection values of the throttle valves detected by the respective angle sensors 5 and 6, the CPU 21 and 2
B. Input parts 20, 2 of motors 3, 4 and electronic control device 8
7. An abnormality in the drive unit 26, 33, etc. can be detected.

〔Effect of the invention〕

As described above, according to the present invention, additional controls such as constant speed cruise control and traction control control can be executed with a simple configuration, and a throttle valve control device with improved reliability can be implemented. It can be realized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of the electronic control device shown in FIG. 1, FIG. 3 is a flowchart of control performed by the electronic control device shown in FIG. 1, and FIG. FIG. 5, which is an explanatory diagram of fail operation when a CPU fails, is a configuration diagram showing an outline of the present invention. 1.2... Throttle valve, 3, 4... Motor, 7.
...Accelerator opening sensor, 8...Electronic control device t, 1
0...Throntle valve opening command signal generator. Representative Patent Attorney Takashi Okabe Figure 1 Figure 2 Figure 4

Claims (1)

[Scope of Claims] First and second pipes installed in series in the middle of an intake pipe of an internal combustion engine.
a throttle valve, first and second electric actuators that independently drive the first and second throttle valves, an accelerator opening sensor that outputs an accelerator opening signal according to the amount of depression of the accelerator pedal, and an accelerator. Throttle valve opening command output means for outputting opening command signals for the first and second throttle valves independently of the amount of pedal depression; an accelerator opening signal output by the accelerator opening sensor; outputting control signals to the first and second electric actuators based on the opening command signal outputted by the valve opening command output means, and controlling the openings of the first and second throttle valves separately. Monitoring to detect abnormal conditions by monitoring the operating states of two systems constituted by first and second control means, the first and second throttle valves, an electric actuator, and the control means. When an abnormal state is detected in the operating state of one of the systems by the means and the monitoring means, the control based on the opening command signal is prohibited, and the first and second systems are controlled based only on the accelerator opening signal. 2. A throttle valve control device comprising: prohibition control means for controlling a throttle opening degree.