JPH0774623B2 - Slot valve control device - Google Patents

Description

The present invention relates to a throttle valve control device for controlling the opening of a throttle valve provided in a vehicle engine.

[Conventional technology]

Conventionally, a throttle valve provided in a vehicle engine has been directly connected to an accelerator pedal through a link mechanism, and has been mechanically driven according to the amount of depression of the accelerator pedal by a driver.

In recent years, many devices have been proposed that electrically detect the accelerator operation amount and control the opening of the throttle valve by an electric actuator such as a motor according to the detected accelerator operation amount.

In order to improve the reliability and safety of such an electrically controlled throttle valve control device, for example, the actual open shovel 60-
As shown in Japanese Patent No. 122549, when the deviation between the accelerator pedal signal and the throttle valve signal is a set value or more and the set value continues for a set time or longer, a technique for stopping fuel injection or ignition is known. Is.

[Problems to be solved by the invention]

However, in the abnormality detection by the method as disclosed in the above publication, i) the deviation is less than or equal to the set value, but if the deviation constantly occurs, ii) the deviation far exceeds the set value. If it exceeds, but if the duration is shorter than the set time, then there was a problem that abnormalities such as could not be judged as abnormal at all.

Further, in the abnormality detection of the method as disclosed in the above publication, even if the abnormal movement that the deviation is equal to or larger than the set value continues for a long time, it can be determined as abnormal because the setting is performed after the abnormal movement occurs. There is also a problem that the abnormality can be determined only after a lapse of time, and thus the abnormality cannot be detected promptly.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a throttle valve control device capable of promptly and surely detecting an abnormality in the driving state of the throttle valve.

[Means for solving problems]

In order to solve the above problems, in the present invention, as shown in FIG. 13, a throttle valve for adjusting the amount of air taken into an engine mounted on a vehicle, an actuator for driving the throttle valve, and An opening degree detecting means for detecting an actual opening degree of the throttle valve, an operating state detecting means for detecting an operating state of the vehicle and the engine, and an operation state detecting means for detecting the operating state of the throttle valve based on the operating state detected by the operating state detecting means. An opening degree setting means for setting a target opening degree, a drive signal output means for outputting a drive signal according to the target opening degree of the throttle valve set by the opening degree setting means to the actuator, and the opening degree detecting means. Deviation calculating means for obtaining a deviation between the actual opening of the throttle valve detected by the above and the target opening of the throttle valve set by the opening setting means, and the deviation calculating means. An integral value calculating means for obtaining an integrated value of the obtained deviation in a predetermined period, and a determining means for determining an abnormality when the integrated value obtained by the integral value calculating means is larger than a predetermined determination value, The throttle valve control device is characterized in that the determination value in the determination means is set to a larger value when the temperature is low than when the temperature is high, according to the temperature of the actuator.

[Action]

According to the above configuration, the drive signal output unit outputs the drive signal corresponding to the target opening set by the opening setting unit to the actuator, so that the actuator drives the throttle valve and is sucked into the engine. The amount of air used is adjusted. At that time, the deviation between the actual opening of the throttle valve detected by the opening detecting means and the target opening set by the opening setting means is obtained by the deviation calculating means, and the integrated value of the deviation within a predetermined period is obtained. Is calculated by the integral value calculating means. If this integrated value is greater than the determination value set to a larger value depending on the temperature of the actuator when the temperature is low or high, it is determined that there is an abnormality in the throttle valve drive system. To be done.

〔Example〕

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

FIG. 1 is a configuration diagram showing a schematic configuration of the present embodiment. An engine 1 is a spark ignition type four-cylinder engine mounted on a vehicle. The engine 1 includes an intake pipe 2 and an exhaust pipe 3. It 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 on 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 1 is provided on the downstream side thereof. An intake air temperature sensor 5 that detects the intake air temperature is provided between the air cleaner and the throttle valve 4. Further, on the outer peripheral wall of the collecting pipe 2a, there is provided a reversible motor 6 serving as a throttle valve driving actuator having a rotor connected to the rotary shaft of the throttle valve 4. The motor 6 is, for example, a step motor or a step motor. It consists of a DC motor. A temperature sensor 6a is attached to the motor 6 at a position close to the bearing portion in order to detect the temperature near the bearing portion (not shown) of the motor 6.
The throttle valve 4 is attached to the other end of the rotary shaft of the throttle valve 4.
A spring (not shown) for urging the throttle valve 4 toward the fully closed position and an opening sensor 7 for detecting the actual opening of the throttle valve 4 that outputs an analog signal according to the opening of the throttle valve 4 are provided.

An intake pressure sensor 8 for detecting the intake pressure in the surge tank is connected to the surge tank 2b.
An electromagnetically operated injection valve 9 for injecting fuel is provided near the intake valve (not shown) of the engine 1 at 2c.

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 for detecting the water temperature of the cooling water for cooling the engine, and a rotation sensor 12 for detecting the engine speed that generates a pulse signal according to the rotation speed of the engine 1.

Reference numeral 20 denotes an electronic control unit (ECU) whose main part is composed of a microcomputer, which inputs an engine status signal from each of the above sensors and outputs a drive signal to the motor 6 and the injection valve 9. In addition to the above sensors, the ECU 20 receives a signal from the accelerator sensor 13 connected to the accelerator pedal 13a operated by the driver, the signal corresponding to the operation amount.

Reference numeral 14 is a battery that supplies electric power to the ECU 20.
By the way, an IG switch 15 operated by the driver is provided in the middle of the energization line from the battery 14 to the ECU 20.

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

The main structure of the ECU 20 is shown in FIG. Reference numeral 21 denotes a command for turning on the warning lamp 17, etc., if necessary, for calculating the valve opening time of the injection valve 9, the driving amount of the motor 6 and the abnormality judgment of the throttle valve drive system based on the signals from the above-mentioned sensors and the like. Is a CPU that does. 22 is a ROM which is a read-only memory in which constants and data used in the processing of the CPU 21 are stored, and 23 is a temporary storage of the calculation result obtained by the COU 21 and the detection data from each sensor. RAM, which is a writable memory. RAM23 is ECU2
The memory contents are retained even when power supply to 0 is lost. An input unit 24 receives signals from each sensor and performs signal processing such as A / D conversion and waveform shaping on these signals. twenty five
Is an output unit, which outputs a signal for driving the injection valves 9 ... And the motor 6 and a signal for lighting the warning lamp 17 based on the processing result executed by the CPU 21. 26 is a common bus, CPU21, RO
The M22, the RAM 23, the input unit 24, and the output unit 25 are connected to each other and used for mutual data transmission. 27 is an electric circuit, IG switch
It is connected to the battery 14 via 15, CPU21, ROM22,
Power is supplied to the RAM 23, the input unit 24, and the output unit 25.

FIG. 3 shows a flow chart of a program executed as a main routine by the CPU 21, and in particular, only an example of a control program portion for the throttle valve 4 is shown without being shown.

In FIG. 3, when the IG switch 15 is turned on and electric power is supplied to the ECU 20, the processing of this main routine is started. First, at step 301, data at a predetermined address in the RAM 23, the input unit 24, and the output unit are output. Perform 25 initializations. In step 302, the motor temperature T _M , intake air temperature T _A , actual throttle opening θ _S , intake air pressure P _m , water temperature T _w , rotation speed N _e , air-fuel ratio signal S _{A / F} , accelerator operation amount θ _A are taken in. In step 303, the basic target opening degree θ of the throttle valve 4 is calculated based on the accelerator operation amount σ _{A.
The SO} is read from the basic target opening map stored in the ROM 22, and a correction value is calculated based on each of the other signals, and the basic target opening θ _SO is corrected by this correction value to obtain the current target opening θ _SS . calculate. In step 304, this target opening θ _SS
The control amount D _{S of} this time is read from the control amount map stored in the ROM 22 based on the above.

In step 305, it is determined whether or not the flag F stored in the RAM 23, which indicates an abnormal state of the throttle valve 4 to be described later, is "0". If "0", step 307 is performed. If "1", step 306 is performed. Proceed to. It should be noted that if the flag F is “0”, it is normal, and if it is “1”, it is abnormal. In step 306, the control amount D _S obtained in step 304 is canceled and set to 0 before the operation proceeds to step 307. In step 307, the control amount D obtained through the above steps is calculated.
_{The S} is output to the output unit 25. After that, after processing other control programs, the process returns to step 302 again.

By the above processing, if the flag F is "0", the output unit 25 forms a signal for driving the throttle valve 4 according to the control amount D _S , and then outputs this drive signal to the motor 6. Then, the motor 6 rotationally drives the throttle valve 4 based on the drive signal, so that the throttle valve 4 is adjusted to the optimum opening degree from the accelerator operation amount θ _A and the engine state at that time. When the flag F is "1", the drive signal to the motor 6 is not output from the output unit 25, the power supply to the motor 6 is cut off, and the throttle valve 4 is fully closed by the spring.

Further, the injection time for the injection valve 9 is obtained by the CPU 21 by means known in the art, and the injection valve 9 is driven by the pulse-shaped drive signal corresponding to the injection time from the output unit 25, and the branch pipe 2c
A predetermined amount of fuel is injected into the inside.

FIG. 4 is a flow chart of a program for determining an abnormality in the driving state of the throttle valve 4,
For example, it is executed as an interrupt routine every 50 ms.

First, in step 401, it is checked based on the flag F whether or not the driving state of the throttle valve has been determined to be abnormal in the previous routine processing. If it is "1", this routine is terminated, and if it is "0". If so, proceed to step 402. In step 402, the absolute value of the deviation from the target opening θ _SS of the throttle valve 4 obtained in the main routine described above is obtained and is set to ΔA ₀ . Next, at step 403, ΔA ₀ obtained at step 402 is added to the integral value I obtained at the previous routine processing, and ΔA ₅ stored at the previous routine processing is subtracted. Then, the integral value I is updated. That is, in this step 403, ΔA ₀ is added and ΔA ₅ is subtracted, so that the target opening θ _SS within the predetermined time
The integral value I of the deviation ΔA between the actual opening θ _S and the actual opening θ _S is calculated.
In step 404, the integrated value I obtained in step 403 is compared with a judgment value K predetermined according to the motor temperature T _M as shown in FIG. 5, and if I <K, it is normal. If it is determined that I ≦ K in step 403, it is determined to be abnormal, and the process proceeds to step 405. In step 405, the flag F is rewritten as "1" and R is written.
It is stored in the AM 23, and in step 406, a command is given to the output unit 25 to turn on the warning lamp 17, and this routine ends.

Further, in steps 407 to 412, the integrated value I is stored in the RAM 23 for the subsequent routine processing, and ΔA ₀
Is ΔA ₁ , ΔA ₁ is ΔA ₂ , ΔA ₂ is ΔA ₃ , and
The .DELTA.A ₃ as .DELTA.A _4, leave the .DELTA.A ₄ respectively are stored in the RAM23 as .DELTA.A _5, the routine ends.

According to the process shown in FIG. 4, if the actual opening θ _S is satisfactorily following the target opening θ _SS as shown in FIG. However, the deviation ΔA between the target opening θ _SS and the actual opening θ _S becomes large as shown in FIG. 7 and is long. In this case, since the integrated value I exceeds the determination value K, it is determined to be abnormal. Further, as shown in FIG. 8, even when the actual opening θ _S cannot be sufficiently tracked and a large deviation ΔA temporarily occurs when the target opening θ _SS greatly changes, the large deviation ΔA Since the integrated value I within the predetermined time including the value exceeds the determination value K, it is determined to be abnormal, and further, as shown in FIG.
Although there is a response of the actual opening θ _S to the change of _SS , the integrated value I of the deviation ΔA within the predetermined time exceeds the judgment value K even if the deviation ΔA constantly occurs. Therefore, it is determined to be abnormal.

Further, as shown in FIG. 10, even when the actual opening θ _S is largely hunted around the target opening θ _SS , the integrated value I of the deviation ΔA within the predetermined time is the judgment value K.
It is judged to be abnormal because it exceeds.

If it is determined that the driving state of the throttle valve 4 is abnormal as described above, the warning lamp 17 is turned on and the energization of the motor 6 is cut off in the program processing of FIG. .

Therefore, according to the present embodiment, when the target opening θ _S changes significantly, the throttle valve 4 cannot sufficiently follow the drive response of the throttle valve 4, and the target opening θ _SS is almost constant. Even when the throttle valve 4 has a steady deviation from the actual opening θ _S , or the throttle valve 4 is largely hunting, the position controllability of the throttle valve 4 is impaired. This makes it possible to reliably determine an abnormality, and since the determination is made based on the integral value I of the deviation between the target opening degree θ _{SS and} the actual opening degree θ _S within a predetermined time, this integral value I is determined by a predetermined value. Since it reflects the deviation between the target opening θ _SS and the actual opening θ _S for the time,
It becomes possible to detect an abnormal state much faster than the abnormality determination as seen in the above publication.

Further, in a state where the movement of the motor 6 is dull such as when the engine 1 is started at a low temperature, the actual opening θ _S of the throttle valve 4 cannot necessarily follow the target opening θ _SS , and this external factor causes Although the integrated value I becomes large, in this embodiment, the judgment value K is set to become larger toward the lower temperature side according to the motor temperature T _M , so that it is possible to prevent erroneous judgment due to external factors. In this embodiment, the temperature T _M in the vicinity of the bearing of the motor 6 is directly detected by the temperature sensor 6a.
As it itself becomes warm and the movement of the motor 6 also improves,
The set value K in accordance with the water temperature T _W of the cooling water may be set. Further, from the same reason, the determination value K may be set according to the intake air temperature T _A.

Further, as shown in FIG. 11, the engine cooling water is guided around the motor 6, and the judgment value K is determined according to the water temperature T _W as described above.
May be set. In this way, deterioration of operability due to excessive cooling of the motor 6 due to the ambient temperature is prevented.

Furthermore, the accelerator pedal 13a is suddenly depressed,
If the target opening θ _SS suddenly changes, the motor 6
Due to the response delay of, the deviation naturally occurs between the target opening θ _SS and the actual opening θ _S. Therefore, in consideration of such a response delay, the determination value K may be increased and corrected according to the amount of change in the accelerator operation amount θ _A. In this embodiment, since the spring for urging the throttle valve 4 in the fully closing direction is provided, the correction amount is changed depending on whether the opening direction is changed or the closing direction is changed. In this case, it is preferable to make correction so that the determination value K becomes larger.

By the way, in the above embodiment, the integrated value I is obtained from the total of five deviations of the deviation during the execution of the interrupt routine of FIG. Is set to.

In the above embodiment, the interrupt routine shown in FIG. 4 for determining an abnormality in the drive state of the throttle valve is executed every 50 ms, but the time interval is set arbitrarily according to the determination accuracy. It

Further, in the above embodiment, when it is determined that there is an abnormality, the power supply to the motor 6 is cut off and the warning lamp 17 is turned on. Instead of cutting off the power supply to the motor 6, as shown in FIG. The fuel injection from the injection valve 9 may be cut off. That is, FIG. 12 shows an injection amount calculation routine executed in synchronization with engine rotation.
If the flag F is "1", the process is terminated without outputting the calculated injection amount τ. Therefore, since the drive signal is not output from the output unit 25 according to the injection valve 9, the fuel injection is cut.

Further, in the above embodiment, the target opening θ _SS of the throttle valve 4 is obtained from the signals from the respective sensors, the control amount D _S corresponding to this target opening θ _SS is determined, and the drive signal corresponding to this control amount D _S is determined. The opening degree of the throttle valve 4 was controlled by giving the motor 6 to the motor 6. However, the target opening degree θ _SS of the throttle valve 4 is determined from the signal from each sensor, and the throttle opening degree θ _S from the opening degree sensor 7 is determined. Is calculated, the control amount D _S is integrated based on this deviation, and a drive signal corresponding to this control amount D _S is obtained by the motor 6
The feedback control may be performed by giving it to.

In the above embodiment, the rotation of the motor 6 is transmitted to the shaft of the throttle valve 4 to adjust the opening of the throttle valve 4. However, as shown in Japanese Patent Laid-Open No. 59-20539, the motor 6 is controlled by the ECU 20. The throttle valve 4 may have a rod that moves forward and backward in response to a drive signal from the lever, and the throttle valve 4 may be provided with a lever portion that abuts on the rod so that the opening of the throttle valve 4 can be adjusted by the movement of the rod. .

〔The invention's effect〕

As described above, according to the present invention, a large deviation occurs between the target opening and the actual opening, and the deviation is not so large, not to mention the abnormal state where this deviation continues for a long time. However, an abnormal state where a steady deviation occurs, an abnormal state where the actual opening cannot follow the target opening when the target opening greatly changes, or the actual opening is relative to the target opening. It has an excellent effect that it is possible to reliably detect any abnormal state such as a large hunting abnormal state, and the integrated value reflects the deviation for a predetermined time. The integrated value increases in proportion to the magnitude of the deviation and exceeds the judgment value, so that there is also an excellent effect that an abnormal state can be quickly detected. Furthermore, the lower the temperature of the actuator, the worse the responsiveness of the actuator.
Even if it is not in an abnormal state, the integrated value increases correspondingly, and if the determination value is constant, it may be erroneously determined to be abnormal, but as in the present invention, the temperature may be changed depending on the temperature of the actuator that drives the throttle valve. When the value is low, the judgment value is set to a larger value than when the value is high, which has an excellent effect that erroneous judgment due to the temperature of the actuator can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing the configuration of an embodiment of the present invention, and FIG.
FIG. 1 is a block diagram showing the configuration of the ECU of FIG. 1, FIGS. 3 and 4 are flowcharts of programs executed by the CPU of FIG. 2, and FIG. 5 shows the judgment value K and the motor temperature T _M. A characteristic diagram showing the relationship, and Fig. 6 shows the target opening θ _SS and the actual opening θ during normal operation.
Time charts showing changes with _S , Figs. 7 and 8
FIGS. 9, 9 and 10 are time charts showing changes in the target opening θ _SS and the actual opening θ _S at the time of abnormality, and FIGS. 11 and 12 show another embodiment of the present invention. Configuration diagram and flowchart, FIG. 13 is a block diagram showing a schematic configuration of the present invention. 1 …… Engine, 2 …… Intake pipe, 4 …… Throttle valve, 6 ……
Motor, 6a …… Temperature sensor, 7 …… Opening sensor, 9 …… Injection valve, 11 …… Water temperature sensor, 13 …… Accelerator sensor, 20 …… EC
U, 21 …… CPU, 22 …… ROM, 23 …… RAM.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 61-54329 (JP, A) JP 61-87938 (JP, A) JP 60-108541 (JP, A)

Claims (2)

[Claims] 1. A throttle valve for adjusting the amount of air taken into an engine mounted on a vehicle, an actuator for driving the throttle valve, an opening detection means for detecting an actual opening of the throttle valve, Operating state detecting means for detecting an operating state of the vehicle and the engine; opening setting means for setting a target opening of the throttle valve based on the operating state detected by the operating state detecting means; and the opening setting Drive signal output means for outputting to the actuator a drive signal corresponding to the target opening of the throttle valve set by the opening means, the actual opening of the throttle valve detected by the opening detection means, and the opening setting means Deviation calculation means for calculating the deviation from the target opening of the throttle valve set in step 1, and different if the integrated value calculated by the deviation calculation means is larger than a predetermined judgment value. A throttle valve control device, comprising: a determining unit that determines that the temperature is constant, and a determination value of the determining unit is set to a larger value when the temperature is low than when the temperature is high. . 2. The determination value of the determination means is greater when the temperature of at least one of the actuator temperature, the engine cooling water temperature, and the engine intake air temperature detected by the operating state detection means is lower than when the temperature is high. The throttle valve control device according to claim 1, wherein the throttle valve control device is set to a value.