JPS63138133A - Throttle valve control device - Google Patents

Abstract

PURPOSE:To ensure high reliability, by a method wherein response of a change in the opening of a throttle valve is monitored based on an output from a throttle valve opening detecting means, and based on the response of the throttle valve, abnormality on the driven system of the throttle valve is previewed. CONSTITUTION:A throttle valve device controls drive of an actuator B by means of a command signal, generated by a command means A according to the running state of an engine to regulate the opening of a throttle valve. In this case, a monitoring means D is provided for monitoring response to a change in the opening of the throttle valve, produced by means of a command signal from the command means A, based on the opening of the throttle valve, detected by means of a throttle opening detecting means C. From the monitoring result, an abnormality preview means E decides that the drive system of the throttle valve is normal when response is within an allowable range, meanwhile, the means decides that a friction force at the drive system of the throttle valve is increased and there is a risk of lock occurring when response is deteriorated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a throttle valve control device for controlling the opening degree of a throttle valve provided in, for example, a vehicle engine.

[Conventional technology]

Throttle valves traditionally installed in vehicle engines are
It was directly connected to the accelerator pedal via a link mechanism, etc., and was mechanically driven according to the amount of depression of the accelerator pedal by the driver.

Recently, sensors have been used to detect the amount of accelerator pedal depression,
Many devices have been proposed that adjust the opening degree of the throttle valve via an electric actuator based on this detection signal and a detection signal from a sensor that detects the engine condition. In such a throttle valve control device, a technique for detecting a failure in the throttle valve drive system (control circuit → actuator throttle valve) and improving the reliability of the device is disclosed in Japanese Patent Application Laid-Open No. 119036/1983. There is something to be shown.

In this publication, before the engine starts when the ignition switch is turned on, a drive signal to open the throttle valve is given to the actuator that drives the throttle valve, and the commanded opening of the throttle valve and the actual opening of the driven throttle valve are determined. When the difference between the throttle valve and the throttle valve is greater than a predetermined value, it is determined that a failure has occurred in the throttle valve drive system, and a warning is given to the driver.

[Problem that the invention seeks to solve]

However, in the configuration shown in the above publication, if a failure occurs in the throttle valve drive system due to a previous operation, and the above process is performed at the next starting opportunity, it becomes possible to warn the driver for the first time. However, no consideration is given to the naturally occurring case where the actuator locks (does not move) while the vehicle is running, for example. In other words, in the system disclosed in the above-mentioned publication, the driver is warned after a failure occurs in the throttle valve drive system, so the timing of warning the driver is delayed and reliability is compromised. It was still inadequate.

Therefore, an object of the present invention is to provide a throttle valve control device that guarantees high reliability by predicting the risk of failure in the throttle valve drive system.

[Means for solving problems]

It is extremely rare for the throttle valve to suddenly lock even though there is no abnormality in the throttle valve drive system; for example, friction may gradually occur over time in the actuator or the throttle valve bearing. Based on the knowledge of the present inventors that in most cases, the force increases and eventually locks up, in order to solve the above problem, in the present invention, as shown in FIG. an actuator for driving the throttle valve; an opening detecting means for detecting the opening of the throttle valve; and a valve for driving the throttle valve by the actuator. a command means for giving a command signal; a monitoring means for monitoring the responsiveness of the opening degree change of the throttle valve due to the command signal of the command means based on the throttle valve opening degree detected by the opening degree detection means; The throttle valve control device is characterized in that it includes an abnormality prediction means for predicting an abnormality in the drive of the throttle valve based on the responsiveness of the throttle valve monitored by a monitoring means.

[Effect]

According to the above configuration, the throttle valve is driven in accordance with the command signal given to the actuator by the command means, and the throttle valve responsiveness is detected by the opening detection means by the monitoring means. Monitored based on valve opening. Then, the abnormality prediction means predicts an abnormality in the throttle valve drive system from the responsiveness monitored by the monitoring means.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing the schematic structure of this embodiment. The engine is a spark ignition four-cylinder engine mounted on a vehicle. This engine 1 includes an intake pipe 2 and an exhaust pipe 3.
is connected.

The intake pipe 2 is composed of a collecting pipe 2a, a surge tank 2b, and a branch pipe 2C that branches corresponding to each cylinder of the engine 1. An air cleaner (not shown) is provided at the most upstream side of the collecting pipe 2a of the intake pipe 2, and a throttle valve 4 for adjusting the amount of air taken into the engine is provided at the downstream side thereof.

Further, an intake air temperature sensor 5 for detecting intake air temperature is provided between the air cleaner and the throttle valve 4. Furthermore, a reversible motor 6 serving as a throttle valve driving actuator having a rotor connected to the rotating shaft of the throttle valve 4 is provided on the outer peripheral wall of the collecting pipe 2a. Consists of a DC motor.

Further, the other end of the rotating shaft of the throttle valve 4 is provided with a throttle valve 4.
An opening sensor 7 is provided to detect the throttle valve opening and output an analog signal corresponding to the opening of the throttle valve.

An intake pressure sensor 8 for detecting the intake pressure in the surge tank is connected to the surge tank 2b, and an intake valve (not shown) of the engine l is connected to each branch pipe 2c.
An electromagnetically actuated injection valve 9 for injecting fuel is provided nearby.

The exhaust pipe 3 is provided with an air-fuel ratio sensor 10 for detecting the air-fuel ratio from the residual oxygen concentration in the exhaust gas.

The engine 1 is provided with a water temperature sensor 11 that detects the temperature of cooling water for engine cooling, and a rotation sensor 12 that detects the engine rotation speed that generates a pulse signal corresponding to the rotation speed of the engine 1.

Reference numeral 20 denotes an electronic control unit (ECU) whose main part is a microcomputer "i'fi", into which engine status signals from the above-mentioned sensors are input, and which controls the motor 6,
A command signal for instructing the injection valve 9 to drive is given. In addition to the above-mentioned sensors, the ECU 20 receives a signal corresponding to the amount of raking from an accelerator sensor 13 connected to an accelerator pedal 13a operated by the driver.

Note that 14 is a battery, which supplies power to the ECU 20. By the way, a key switch 15 operated by the driver is provided in the middle of the energizing line 14a from the battery 14 to the ECU 20, and a delay circuit 1 is provided in the middle of the energizing line 14b provided in parallel with the energizing line 14a.
6 is provided. The delay circuit 16 is triggered by the ON of the key switch 15, and is configured to turn OFF after a predetermined time delay (approximately 35 ec) with respect to the OFF of the key switch 15. Therefore, the ECU 20 is supplied with power from the battery 14 for a predetermined period of time after the key switch 15 is turned off.

Further, 17 is a warning lamp mounted on a meter panel (not shown) in the driver's seat, and is turned on by the ECU 20.

The main configuration of the ECU 20 is shown in FIG. 2. 21 determines the opening time of the injection valve 9 based on signals from the above-mentioned sensors, etc.;
The CPU calculates the drive amount of the motor 6, checks the throttle valve drive system, and issues a command to turn on the warning lamp 17 if necessary. 22 is a ROM which is a read-only memory in which constants and data used in processing by the CPU 21 are stored; 23 is a CPU
RA is a writable memory that temporarily stores the calculation results obtained in step 21, detection data from each sensor, etc.
It is M. Note that the RAM 23 is configured so that its stored contents are retained even when power is no longer supplied to the ECU 20. 24 is an input unit that receives signals from each sensor and also applies A/D to these signals.
Executes signal processing such as conversion and waveform shaping. Reference numeral 25 denotes an output section, which outputs a signal for driving the injection valve 9 and the motor 6, as well as a signal for lighting the warning lamp 17, based on the processing results executed by the CPU 21. 26 is a common bus, and CPU2
1. ROM22. RAM23, input section 24. Output section 25
It is used for interconnecting data and for mutually transmitting data. 27 is a power supply circuit, which is connected to the current supply lines 14a and 14'b, and is connected to the CPU 21. ROM22. RAM23. Power is supplied to the input section 24 and output section 25.

FIG. 3 shows a flowchart of a program executed as a main routine by the CPU 21, and in particular only one example of the control program portion for the throttle valve 4 is shown.

In FIG. 3, the key switch 15 is turned on and the ECU 20
Processing of this main routine is started by supplying power to the RAM 23.
Data on designated locations in the Human Resources Department 24. The output unit 25 is initialized. In step 302, the intake air temperature signal TA,
Throttle opening degree θ8. Intake pressure signal PR1 Water temperature signal T
. Number of revolutions per rotation No. 0. Air-fuel ratio signal S A/FT accelerator operation amount operation amount signal is involved. In step 303, the basic target opening degree θ of the throttle valve 4 is determined based on the accelerator operation amount θ1. is read out from the basic target opening degree map stored in the ROM 22, and a correction value is determined based on each other signal, and the basic target opening degree θ3o is corrected using this correction value to obtain the current target opening degree θ8. Calculate. In step 304, this target opening degree θ8. The current control amount is based on RO
The control amount map stored in M22 is read out, and in step 305, this control f1. is output to the output section 25. Then, after processing other control programs, the process returns to step 302.

Through the above processing, the output section 25 forms a command signal for driving the throttle valve 4 according to the control value, and then outputs this command signal to the motor 6. Then motor 6
rotates the throttle valve 4 based on the command signal, so that the throttle valve 4 is adjusted to the optimum opening determined by the accelerator operation amount signal θ and various engine parameters.

Further, the injection time for the injection valve 9 is determined by the CPU 21 by a conventionally well-known means, and the injection valve 9 is driven by a pulsed command signal from the output section 25 according to the injection time, and a predetermined amount of injection is injected into the branch pipe 2c. Inject.

FIG. 4 is a flowchart of a program for predicting an abnormality (failure) in the drive system (7) of the throttle valve 4, and is started when the key switch 15 is turned from ON to OFF.

As mentioned above, even if the key switch 15 is turned off, the delay circuit 16 allows the EC1J20 to close the energized line 14b.
Since power is supplied through the CPU 21, the processing by the CPU 21 can also be continued. Furthermore, a power supply line and a delay circuit 1 (not shown) are also connected to the motor 6 that drives the throttle valve 4.
The configuration is such that power is supplied from a battery 14 via a battery 14 .

In FIG. 4, in step 401, it is determined whether the throttle valve 4 is fully open based on the signal from the opening sensor 7. If it is fully closed, the process proceeds to step 404, and if not, the process proceeds to step 402.

In step 402, a command to fully close the throttle valve 4 is given to the output section 25, and in step 403, it is confirmed whether the throttle valve 4 is fully opened. In step 404, a stepwise control amount as shown in FIG. 5 is carried out. is applied to the output section 25, and the output section 25 outputs a restep yarn command signal to the motor 6. In step 405, it is determined whether a predetermined time has elapsed since the command signal was output, and if the predetermined time has elapsed, the process proceeds to step 406. In step 406, the current throttle opening signal θS detected by the opening sensor 7 is taken in, and in step 407, the control amount is determined. It is determined whether the current throttle opening is within the opening range in which an allowable range is set for the target opening corresponding to Proceed to. Note that θ, 1 indicates the lower limit of the opening range, and θ, 2 indicates the upper limit of the opening range.

In step 408, the flag F in the RAM 23, which indicates that there is a sign of failure in the throttle valve drive system, is set to "0" and the process proceeds to step 410. Further, in step 409, the flag F is set to "1" and the process proceeds to step 410. Step 4
At step 10, a fully close command is given to the output section 25 to fully open the throttle valve 4, and this routine ends.

In other words, according to the process shown in FIG. 4, it is determined that the throttle valve 4 is opened to a predetermined opening determined by the control amount 1) so before a predetermined period of time has elapsed. That is, the responsiveness when the throttle valve is driven is monitored in the process shown in FIG. As shown by the solid line A in FIG. 5, if the predetermined opening degree is reached within a predetermined time, that is, if the drive response of the throttle valve 4 is within the allowable range, it is normal and will continue for the time being. If it is determined that there is no risk of failure in the drive system of the throttle valve 4, and if it has not reached the level shown by broken line B, that is, if the drive response of the throttle valve 4 has deteriorated, the throttle It is determined that the frictional force within the bearing of the valve 4 and the motor 6 is increasing and there is a risk of locking, and each state is memorized and held by a flag F.

Note that the predetermined time t is set in consideration of a permissible change over time in the responsiveness due to the initial characteristics of the drive system of the throttle valve 4.

FIG. 6 is a flowchart of a program executed as part of the initialization process in step 301 in FIG.
If it is “1”, step 60
2, if it is "0", this routine is ended and the next process is started. In step 602, a warning lamp 17-ON command is given to the output section 25 to notify the driver that there is a risk of failure in the drive system of the throttle valve 4, and the warning lamp 17-ON command is given to the output unit 25 to turn on the warning lamp 17. Move to.

According to the above embodiment, the drive response of the throttle valve 4 is monitored in the process shown in FIG. 4, and if the response deteriorates below the allowable range, there is a high possibility that a failure will occur in the drive system of the throttle valve 4. By determining that this has occurred, it is possible to notify the driver of the possibility of a failure before a failure occurs in the drive system of the throttle valve 4, thereby preventing the throttle valve 4 or motor 6 from locking up while driving. It will be possible to prevent it from happening.

Note that even if the warning lamp 17 warns the driver of the possibility of failure, since the vehicle is actually drivable, it is natural that the driver will continue to drive to a repair shop. If it locks up while driving, it is dangerous, so if the flag F is "1" and the rotational speed N is 1300 rpm or more, the fuel is cut off, as shown in Figure 7. If you do this, you will be able to maintain a safe state even if the car locks while you are driving.

By the way, in the above embodiment, the key switch 15 changes from ON to OFF.
Although monitoring of the drive response of the throttle valve 4 was executed at the time of F, it may be executed when the fuel is cut.

FIG. 8 is a flowchart showing a processing program in that case, which is executed as a 40n+s interrupt routine.

First, in step 801, it is determined whether or not the fuel is being cut. If the fuel is being cut, step 401 in FIG.
Steps 802 to 81 carry out the same processing as that of steps 802 to 409.
0, and in step 811 the warning lamp 1 is turned on.
7 should be lit (instruct the output section 25, step 81
2, the output unit 25 is commanded to fully close the throttle valve 4.

Furthermore, in each of the above embodiments, it is determined whether the drive response of the throttle valve 4 is within the allowable range based on the throttle opening degree θ after a predetermined time has elapsed. After issuing a command to open to the opening degree, the time taken to reach the opening degree may be measured, and responsiveness may be determined based on whether the time is within an allowable range.

A specific example is shown in FIG. 9 as a part of the process shown in FIG.

At step 404, the IDs are controlled. After the output processing, in step 902, it is determined whether the opening degree θ is equal to or higher than the lower limit 031 of the opening degree range shown in FIG. Return to step 901. Also θ,. If the value is above, the counter C is compared in step 904 with a comparison value C0 determined by taking into account the allowable change over time in the initial characteristics of the drive system of the throttle valve 4, and if C≦co, the process proceeds to step 408. , Coco, the process advances to step 409. Note that the counter C is cleared in steps not shown after step 904.

Note that in the case of the process shown in FIG.
3 to step 901, C≧Cr (C+
>Co), and if C≧C3, the process proceeds to step 409, and if C<C, the process proceeds to step 901.

By doing this, step 901 → step 902
→ Step 903 → Unnecessary repetition of step 901 can be eliminated.

Further, in order to know the drive response of the throttle valve 4, a step-like control ID as shown in FIG. In other words, trace the response waveform of the opening of the throttle valve 4 when a step waveform command signal is given to the motor 6, and from the response waveform, determine the time of the transfer function between the throttle opening command value and the throttle opening. A constant may be determined, and if the time constant is smaller than a predetermined value, the flag F may be set to "O", and if it is larger, the flag F may be set to rlJ.

Further, in the above embodiment, the target opening degree θ of the fourth throttle valve is determined based on the signals from each sensor. is determined, and this target opening degree θ8. Deciding on the control scale according to this system? 111itD, by giving the motor 6 a command signal corresponding to the throttle valve 4.
The target opening θ3° of the throttle valve 4 is determined from the signals from each sensor, and the throttle opening θ from the relational sensor 7 is controlled.

Find the deviation from this and control the weight based on this deviation.

It is also possible to perform feedback control by integrating and determining the control amount and giving a command signal to the motor 6 according to this control amount.

Further, in the above embodiment, the rotation of the motor 6 is transmitted to the shaft of the throttle valve 4 to adjust the opening degree of the throttle valve 4, but as shown in Japanese Patent Laid-Open No. 59-20539, The configuration may be such that the throttle valve 4 has a rod that moves forward and backward in response to a drive signal from the ECU 20, and the throttle valve 4 is provided with a lever portion that comes into contact with this rod, so that the opening degree of the throttle valve 4 is adjusted by the movement of the rod. good.

〔Effect of the invention〕

As described above, the present invention includes: a throttle valve that adjusts the amount of air taken into the engine; an actuator that drives the throttle valve; an opening detection means that detects the opening of the throttle valve; command means for supplying a command signal to the actuator in order to drive the throttle valve by the actuator; and the opening detection means detects the responsiveness of the opening degree change of the throttle valve according to the command signal of the command means. and an abnormality prediction means for predicting an abnormality in the drive of the throttle valve based on the responsiveness of the throttle valve monitored by the monitoring means. Since we have developed a throttle valve control device that allows us to predict the possibility of a failure in the throttle valve drive system, we are able to predict the possibility of a failure in the throttle valve drive system, thereby preventing the throttle valve from becoming inoperable, such as locking due to changes in the throttle valve bearing or actuator over time. Since the driver can be informed of a potentially dangerous situation before the problem occurs, it is possible to realize and provide a throttle valve control device with sufficiently high reliability, which is an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the configuration of an embodiment of the present invention, and FIG.
The figure is a block diagram showing the configuration of the EC1J in Figure 1, Figures 3 and 4 are flowcharts of the program executed by the CPU in Figure 2, and Figure 5 is the throttle valve opening according to the program in Figure 4. 6 is a flowchart of a program executed as part of step 301 in FIG. 3, and FIG. 7 is a flowchart illustrating a part of the fuel injection control n program executed by the CPU. , FIG. 8, and FIG. 9 are program flowcharts showing other embodiments of the present invention, and FIG. 10 is a block diagram showing a schematic configuration of the present invention. 1...Engine, 2...Intake pipe, 4...Throttle valve. 6... Motor, 7... Opening sensor, 13... Accelerator sensor, 15... Key switch, 16... Delay circuit, 17... Warning lamp, 20... EC
U, 21...CPU, 22...ROM, 23...
RAM, 24...input section, 25...output section.

Claims (1)

[Scope of Claims] A throttle valve that adjusts the amount of air taken into the engine, an actuator that drives the throttle valve, an opening detection means that detects the opening of the throttle valve, and a throttle valve that controls the throttle valve by the actuator. a command means for giving a command signal to the actuator to drive the actuator; and a throttle valve opening detected by the opening detection means to detect responsiveness of the opening change of the throttle valve due to the command signal of the command means. A throttle valve control characterized by comprising: a monitoring means for monitoring based on the monitoring means; and an abnormality prediction means for predicting an abnormality in the drive of the throttle valve based on the responsiveness of the throttle valve monitored by the monitoring means. Device.