JP2913638B2 - Drive-by-wire type throttle valve controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a throttle valve provided in an intake passage of an internal combustion engine and an artificial pedal such as an accelerator pedal provided in a vehicle operation room such as a passenger compartment. Rather than mechanically connecting the operation member, the throttle valve can be driven by an actuator such as an electric motor, and a control signal based on the operation amount of an artificial operation member such as an accelerator pedal is output to the actuator. The present invention relates to a drive-by-wire type throttle valve control device capable of controlling opening and closing of a throttle valve. [Related Art] Conventionally, various drive-by-wire type throttle valve control devices as described above have been proposed. As an example of such a drive-by-wire type throttle valve control device, a throttle valve disposed in an intake passage of a gasoline engine (internal combustion engine) is rotatable by an electric motor such as a stepper motor (also referred to as a step motor). To the electronic control unit (EC
U), an electric control signal is supplied to rotate the stepper motor by a desired amount (a desired number of steps). Further, information such as the amount of depression of an access pedal as an artificially operated member and information such as vehicle speed are input to the electronic control unit. Based on the information, the electronic control unit determines the optimum throttle opening (throttle opening). The opening degree of the valve) is determined, and the stepper motor is driven to achieve the determined throttle opening degree. The control command to the stepper motor is indicated by the number of steps such as how many steps to rotate right or left, but such control is recognized by the actual rotation position of the stepper motor and the electronic control unit. It is meaningless if the rotation position of the stepper motor does not match. Therefore, conventionally, for example, when the engine is started, the stepper motor is rotated in a direction in which the throttle valve is fully closed, and as a result of this rotation, a switch provided at a throttle opening θ _STD (throttle reference opening) serving as a reference point is operated. Then, an initialization process (or a calibration process) for setting the number of steps of the stepper motor in the electronic control unit to the number of steps (reference number of steps) corresponding to θ _STD is performed. Thereafter, the reference number of steps is set as a stepper motor control reference. The number of output pulses is increased or decreased to the reference step number. [Problems to be Solved by the Invention] However, in such a conventional drive-by-wire type throttle valve control device, initialization or calibration processing for collating the reference opening degree and the reference step number as described above is performed when the engine is started. Sometimes, only once, the stepper motor cannot respond to this request when, for example, the stepper motor is suddenly requested to rotate at high speed in response to an acceleration or deceleration command. There is a possibility that the rotational position (actual throttle opening) of the motor and the rotational position of the stepper motor recognized by the electronic control unit may be deviated, which causes a problem that reliability of subsequent throttle valve control is reduced. . Further, in such a drive-by-wire type throttle valve control device, the failure of the actuator that drives the throttle valve must be immediately detected, and some countermeasures must be taken. However, in the conventional device, the failure of the actuator is simply and reliably detected. There is no means. A first object of the present invention is to solve such a problem. The first object of the present invention is not only to start the internal combustion engine only once, but also to decelerate the engine such that the throttle valve opening / closing control is not hindered. It is an object of the present invention to provide a drive-by-wire type throttle valve control device in which the actuator can be driven for test driving to a reference position every time the throttle valve is detected. Further, a second object of the present invention is to allow the actuator to be test-driven to a reference position each time a deceleration state is detected, and each time it is detected that the actuator is driven to the reference position. It is an object of the present invention to provide a drive-by-wire type throttle valve control device capable of initializing or calibrating a control reference (for example, a stepper motor control reference) for controlling an actuator as described above. Further, a third object of the present invention is to enable the actuator to be test driven to a reference position every time a deceleration state is detected, and to easily and reliably determine whether or not the actuator is out of order by this test drive. And a drive-by-wire type throttle valve control device. [Means for Solving the Problems] For this reason, the drive-by-wire throttle valve control device according to the first invention has an actuator for opening and closing a throttle valve disposed in an intake passage of the internal combustion engine, Opening and closing the throttle valve by outputting a control signal to the actuator based on a detection result from the operation amount detection means for detecting an operation amount of an artificial operation member for operating the internal combustion engine; In a drive-by-wire throttle valve control device provided with a driving means, a deceleration state detecting means for detecting when a brake pedal is depressed when the operation amount of the artificial operation member is zero, and a deceleration state detection means When a deceleration state is detected by the means, a test signal for driving the actuator to a required reference position is provided. And an actuator test means for outputting a signal to the actuator. A drive-by-wire type throttle valve control device according to a second aspect of the present invention, in addition to the configuration according to the first aspect, further includes a reference position detecting means for detecting whether the actuator is driven to the reference position. And initialization means for initializing an actuator control reference when the reference position detection means detects that the actuator has been driven to the reference position. Further, a drive-by-wire throttle valve control device according to a third aspect of the present invention, in addition to the configuration according to the first aspect, includes a reference position detecting means for detecting whether the actuator is driven to the reference position. The condition that the drive of the actuator to the reference position is not detected by the reference position detection means on condition that a test signal for driving the actuator to the reference position is output from the actuator test means. Determining means for determining that the actuator has failed is provided. [Operation] In the drive-by-wire type throttle valve control device according to the first aspect of the invention, the throttle valve is opened and closed by the actuator receiving a control signal based on the operation amount of the artificial operation member from the control means. However, when the operation state during deceleration is detected by the deceleration state detection means, the actuator is driven to the predetermined reference position side by the actuator test means. In the drive-by-wire type throttle valve control device according to the second invention, the actuator is driven toward a required reference position, and the reference position detecting means detects that the actuator has been driven to the required reference position. Then, the initialization means initializes the actuator control reference in the control means. Further, in the drive-by-wire throttle valve control device according to the third aspect of the present invention, the operation state during deceleration is detected by the deceleration detecting means, so that the actuator is driven to the required reference position by the actuator testing means. If the reference position detecting means does not detect that the actuator has been driven to the reference position, the determining means determines that the actuator has failed. [Embodiment] Hereinafter, a drive-by-wire type throttle valve control device as an embodiment of the present invention will be described with reference to the drawings. FIG. 1 (a) is an overall configuration diagram, and FIG. FIG. 2 is a schematic view for explaining the reference position detecting means, and FIG. 3 is a flowchart for explaining the operation. In the present embodiment, as shown in FIG. 1 (a), a stepper motor (an actuator for opening and closing a throttle valve 3 disposed in an intake passage 1 of a gasoline engine (internal combustion engine) E mounted on an automobile). (Motor) 6 is provided. That is, the stepper motor 6 has a pulley 6a having a motor shaft and a pulley 3b having a throttle shaft 3a.
The belt 7 is wound around the throttle valve 3
Can be opened and closed. The stepper motor 6 receives a control signal from an electronic control unit (ECU) 8 including a microprocessor, a memory such as a RAM or a ROM, and an input / output interface to control the rotational drive amount (step amount). It has become so. The electronic control unit 8 includes a stepper motor 6
As a result, in addition to outputting an electric signal for controlling the throttle valve 3, a fuel injection control signal is sequentially output to an electromagnetic fuel injection valve (injector) 4 provided at an intake port of each cylinder. A control signal for shifting gears is supplied to a solenoid valve (not shown) of a hydraulic control unit of the attached automatic transmission TM (the automatic transmission TM and the engine E).
If the torque converter interposed between the first and second motors is provided with a damper clutch, a control signal for turning on and off the damper clutch is included). That is, the electronic control unit 8 includes a computer unit (THC) for controlling the opening and closing of the throttle opening, a computer unit (ECI) for controlling the amount of injected fuel, and a computer unit (ELC) for controlling the shift of the automatic transmission TM. And has the following. The electronic control unit 8 also has an ignition timing control computer. The electronic control unit 8 receives a throttle position sensor 9, an accelerator position sensor 10, a shift position sensor 12, a rotation speed sensor 13, a water temperature sensor 14, a vehicle speed sensor 15, an air flow sensor 16, an intake air temperature sensor 17, and shift information detection. Detection signals from the means 18, the brake sensor 19, the throttle reference point switch 20, and other sensors 21 are input. Here, the throttle position sensor 9 detects the opening of the throttle valve 3, and for example, a potentiometer is used. The accelerator position sensor 10 detects the depression amount (operation amount) of an accelerator pedal 11 as an artificial operation member for operating the vehicle, and functions as an operation amount detection unit and a deceleration state detection unit DM. The shift position sensor 12 detects the lever position (P, R, D, 2, L) of the selector lever 12a, and the rotation speed sensor 13 detects the engine rotation speed from the number of ignition pulses and the like. The water temperature sensor 14 detects the engine cooling water temperature. The vehicle speed sensor 15 detects the actual speed of the vehicle. The air flow sensor 16 is provided near the air cleaner 2 and detects the amount of intake air by detecting the Karman vortex street. The sensor 17 detects the intake air temperature. The shift information detecting means 18 detects shift information such as the transmission output shaft rotation speed and the kickdown drum rotation speed. The brake sensor 19 is turned on when a brake is applied, that is, when a brake pedal is depressed, and turned off when the brake pedal is depressed, thereby detecting a time when the brake is applied, and constitutes a deceleration state detecting means DM together with the accelerator position sensor 10. Here, the deceleration state detection means DM is, for example, a state in which the accelerator pedal is not depressed (the accelerator position sensor 10).
If the accelerator opening detected by the above is the accelerator position and the brake pedal is depressed (the brake sensor 19 is on), it is detected that the vehicle is decelerating. Note that, instead of the accelerator position sensor 10, a switch that can detect whether the accelerator pedal 11 is depressed or not by ON / OFF can be used. The throttle reference point switch 20 is provided at a throttle opening θ _STD (throttle reference opening) position that is equal to or less than the idle opening serving as a reference point, and the stepper motor 6 is connected to a throttle valve reference opening position (hereinafter “reference position”). ), The switch is turned on when it is driven and turned off at other times, and functions as reference position detection means. As shown in FIG. 2, the throttle reference point switch 20 is provided with a throttle reference point adjusting screw 3d screwed to the tip of a throttle arm 3c integral with the throttle shaft 3a.
The throttle reference point switch 20 is turned on and off by the throttle reference point adjustment screw 3d.
Is turned on when the throttle valve 3 is driven to a required opening degree equal to or less than the idle opening degree. The on / off timing of the throttle reference point switch 20 can be adjusted by adjusting the amount of protrusion of the throttle reference point adjustment screw 3d. Other sensors 19 include an atmospheric pressure sensor, an O ₂ sensor provided in the exhaust passage 5 of the engine E, and an acceleration sensor for detecting the acceleration of the vehicle. By the way, as shown in FIG. 1B, the throttle valve control computer (THC) in the electronic control unit 8 converts the electric control signal based on the detection result from the accelerator position sensor 10, the vehicle speed sensor 15, the acceleration sensor, or the like. It has a function of a control means 81 for opening and closing the throttle valve 3 by outputting to the stepper motor 6 (this control means 81 includes means for setting a target vehicle speed or a target acceleration). Thereby, the throttle valve 3
Is controlled by the stepper motor 6 which is not mechanically coupled to the outsell pedal 11 but is actuated by receiving a control signal (electric signal) from the electronic control unit 8 to control the opening and closing. This is why it is called drive-by-wire throttle valve control. Further, the electronic control unit 8 includes a deceleration state detecting means DM.
When the deceleration state of the vehicle is detected, the stepper motor 6 outputs a test signal (electric signal) for driving the stepper motor 6 and thus the throttle valve 3 to the reference position side to the stepper motor 6 (actuator test means) 82 Function. In this case, the test signal output to the stepper motor 6 is a number of steps _SWOT (for example, 40) sufficient to rotate the throttle valve 3 from fully open to fully closed.
(Equivalent to 0 stops). On the condition that the test signal is output from the stepper motor test means 82, the electronic control unit 8 performs the required time (a signal for returning the stepper motor 6 to the reference position is output from the stepper motor test means 82). After a sufficient time for the stepper motor 6 to be normally driven to the reference position), if the throttle reference point switch 20 does not detect that the stepper motor 6 has been driven to the reference position, that is, the throttle reference point switch 20 If is not turned on, it also has a function of failure determination means 83 for determining that the stepper motor 6 has failed. In this case, the failure mode of the stepper motor 6 includes, for example, fixing of the motor shaft of the stepper motor 6, disconnection of the internal coil of the stepper motor 6 and disconnection of the power supply line to the stepper motor 6,
It is considered that the drive circuit for the stepper motor 6 is broken, foreign matter is caught in the throttle valve 3, and the like. When the failure determination means 83 determines that the stepper motor 6 has failed, it displays a signal to that effect on the display means 22.
To display that the stepper motor 6 is out of order. Note that the display means 22 may be a display lamp (indicator), a speaker, or the like. When a display lamp is used as the display means 22, the display means 22 is provided in a place that is easy for the driver to see, for example, an instrument panel. When the throttle reference point switch 20 detects that the stepper motor 6 has been driven to the reference position after the required time has elapsed since the test signal was output from the stepper motor test means 82, the failure determination means 83 A signal indicating that the motor 6 is normal and the initialization process can be performed (this signal is a signal of an exclusive logic (inverted logic) with respect to the signal output to the display means 22) is output to the initialization means 84 of the control means 81. It is also possible to output to. That is, when the electronic control unit 8 is tested to drive the stepper motor 6 to the reference position by the stepper motor test means 82, the throttle reference point switch 20 is turned on and the stepper motor 6 is driven to the reference position. When the failure determination means 83 determines that a failure has occurred and receives a signal to that effect (a signal indicating that it is not a failure), the control means
By setting the number of steps 81 as a stepper motor control reference to the number of steps S _STD corresponding to the throttle reference opening θ _STD , the actual rotation position of the stepper motor 6 and the stepper motor 6 It also has a function of an initializing means 84 for initializing or calibrating the stepper motor control reference by matching the rotational position. Hereinafter, the operation of the drive-by-wire type throttle valve controller according to the present invention will be described with reference to the flowchart of FIG. First, steps a1 and a2 in FIG.
It is detected whether the vehicle is in a decelerating state. That is, in step a1, it is determined whether the accelerator pedal 11 is depressed, and in step a2, it is determined whether the brake pedal is depressed. If the accelerator pedal 11 has not been depressed and the brake pedal has been depressed, the number of steps S _WOT (e.g., 400 steps) corresponding to the fully closed to fully opened throttle is set in the counter n in step a3. Then, in the next step a4, the step motor 6 is driven so as to return the throttle valve 3 by one step, and in the next step a5, the content of the counter n is reduced by one. After detecting whether the throttle reference point switch 20 has been turned on from the off state in step a6, if the throttle reference point switch 20 has not been turned on yet, it is determined whether or not the counter n has become 0 in step a7. judge. Since n is not initially zero, the process returns to step a4, and thereafter, the process of returning to step a4 via steps a4 to a7 is repeated. Thus, the electronic control unit 8 outputs a test signal for driving the stepper motor 6 to the reference position side by one step. If the step motor 6 is operating normally, n
Before = 0, the stepper motor 6 reaches the reference position. Then, since take YES route at Step a6, the next step a8, the throttle step number PPG ₀ as stepper motor control standards have a control means 81 and the throttle reference opening angle of the step number S _STD. This means that the number of steps has been initialized or calibrated. Therefore, thereafter, the initialized throttle step number PPG ₀ , the accelerator position sensor 10 and the vehicle speed sensor
The drive control of the stepper motor 6 is performed by increasing or decreasing the number of output pulses based on information such as fifteen. The drive control of the stepper motor 6 and the opening / closing control of the throttle valve 3 are based on a conventional drive-by-wire type throttle valve control concept (for example, a target vehicle speed and a target acceleration corresponding to the depression amount are set according to the depression amount of an accelerator pedal. Since there is no difference from the concept of opening and closing control of the throttle valve 3), detailed description thereof will be omitted. By the way, if the stepper motor 6 is operating normally in response to the throttle signal _SWOT signal (test signal) from the electronic control unit 8 corresponding to the throttle fully closing to fully opening, that is, if the stepper motor 6 receives the test signal from the electronic control unit 8, If the stepper motor 6 is driven to the reference position side by one step, the throttle reference point switch 20 must be turned on by the time the counter n becomes zero.
If the throttle reference point switch 20 is not turned on even if the value of the value becomes 0, the YES route is taken in step a7, and it is determined that the stepper motor 6 has failed in step a9, and a failure is displayed. In this manner, the stepper motor 6 can be test-driven to the reference position each time the deceleration state of the vehicle that does not cause a failure in the throttle valve opening / closing control is detected, instead of only once when the engine E is started, and thereafter. 6 is detected to be driven to the reference position, the control reference for the stepper motor control as described above can be initialized or calibrated each time, so that the throttle valve opening / closing control by the drive-by-wire method can be performed with high accuracy. And contributes to improvement of control reliability. In addition, it is possible to easily and reliably determine whether or not the actuator is out of order by this test drive, and this also contributes to improvement in control reliability. When the throttle reference point switch 20 is turned on by adding a signal line shown by a chain line in FIG. 1 (b),
Each time, the above-described initialization processing or calibration processing may be performed. Further, instead of using an accelerator pedal operated by a foot, a lever operated by a hand may be used as the artificial operation member. In addition to the stepper motor, an electric motor such as a normal DC motor can be used as the actuator. The drive-by-wire type throttle valve control device can be similarly applied to other engine systems besides the engine system mounted on an automobile. [Effects of the Invention] As described above in detail, according to the drive-by-wire type throttle valve control device according to the first aspect of the invention, not only once when the internal combustion engine is started, but every time a deceleration state is detected, The actuator can be test-driven to the reference position, so it is possible to initialize the actuator control reference or determine the actuator failure state, and easily perform pre-processing to improve the reliability of the drive-by-wire throttle valve control. This greatly contributes to improving control accuracy from a broad viewpoint. Further, according to the drive-by-wire type throttle valve control device of the second invention, each time the deceleration state is detected, the actuator can be test-driven to the reference position, and thereafter, it is detected that the actuator has been driven to the reference position. Then, the actuator control reference can be initialized or calibrated each time, so that the throttle valve opening / closing control by the drive-by-wire system can be performed with high accuracy, which has an advantage of contributing to improvement in control reliability. Further, according to the drive-by-wire type throttle valve control device according to the third aspect of the invention, the actuator can be test-driven to the reference position every time the deceleration state is detected. Since the judgment can be made, this point also greatly contributes to the improvement of the control reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show a drive-by-wire type throttle valve control device as an embodiment of the present invention, wherein FIG. ) Is a control block diagram, FIG. 2 is a schematic diagram for explaining the reference position detecting means, and FIG. 3 is a flowchart for explaining the operation. DESCRIPTION OF SYMBOLS 1 ... Intake passage, 2 ... Air cleaner, 3 ... Throttle valve, 3a ... Throttle shaft, 3b ... Pulley, 4 ... Electromagnetic fuel injection valve (injector), 5 ... Exhaust passage, 6 ...
... Electric motor (stepper motor) as actuator,
6a pulley, 7 belt, 8 electronic control unit (ECU), 9 throttle position sensor, 10
Accelerator position sensor as operation amount detecting means, 11
Accelerator pedal as artificial operation member, 12 Shift position sensor, 12a Selector lever, 13
... Rotation speed sensor, 14 ... Water temperature sensor, 15 ... Vehicle speed sensor, 16 ... Air flow sensor, 17 ... Intake air temperature sensor, 18
… Shift information detection means, 19… Brake sensor, 20…
A throttle reference point switch as a reference position detecting means,
21 ... other sensors, 22 ... display means, 81 ... control means, 82 ... stepper motor test means (actuator test means), 83 ... failure determination means, 84 ... initialization means, DM
... deceleration state detecting means, E: gasoline engine (internal combustion engine), TM: automatic transmission.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02D 9/00-45/00

Claims (1)

(57) [Claims] An operation amount detection means for detecting an operation amount of an artificial operation member for operating the internal combustion engine, comprising an actuator for opening and closing a throttle valve disposed in an intake passage of the internal combustion engine; and the operation amount detection means A drive signal by outputting a control signal to the actuator based on the detection result from the controller to open and close the throttle valve. Deceleration state detecting means for detecting when a brake pedal is depressed,
And a drive-by-wire type, wherein an actuator test means for outputting a test signal for driving the actuator to a required reference position to the actuator when the deceleration state is detected by the deceleration state detection means is provided. Throttle valve control device. 2. An operation amount detection means for detecting an operation amount of an artificial operation member for operating the internal combustion engine, comprising an actuator for opening and closing a throttle valve disposed in an intake passage of the internal combustion engine; and the operation amount detection means A drive-by-wire type throttle valve control device comprising a control means for opening and closing the throttle valve by outputting a control signal to the actuator based on a detection result from the actuator and an actuator control standard. Deceleration state detecting means for detecting when the brake pedal is depressed when is zero,
Actuator test means for outputting a test signal for driving the actuator to a required reference position to the actuator when the deceleration state is detected by the deceleration state detection means is provided, and the actuator is driven to the reference position. Reference position detecting means for detecting whether or not the actuator is driven to the reference position, and initialization means for initializing the actuator control reference when the reference position detecting means detects that the actuator has been driven to the reference position. A drive-by-wire type throttle valve control device, characterized in that: 3. An operation amount detecting means for detecting an operation amount of an artificial operation member for operating the internal combustion engine, comprising an actuator for opening and closing a throttle valve disposed in an intake passage of the internal combustion engine, and the operation amount detecting means; A drive signal by outputting a control signal to the actuator based on the detection result from the drive valve to control the opening and closing of the throttle valve. Deceleration state detecting means for detecting when a brake pedal is depressed,
Actuator test means for outputting a test signal for driving the actuator to a required reference position to the actuator when the deceleration state is detected by the deceleration state detection means is provided, and the actuator is driven to the reference position. Reference position detecting means for detecting whether or not the actuator has been driven to the reference position on condition that a test signal for driving the actuator to the reference position has been output from the actuator testing means. A drive-by-wire throttle valve control device, further comprising: determination means for determining that the actuator has failed when the actuator is not detected by the reference position detection means.