JPH0324854Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a throttle valve control device for electrically driving and controlling a throttle valve of an engine.

(Prior Art) Conventionally, as a method of controlling the throttle valve of an engine, when the accelerator pedal is depressed, the throttle lever is rotated via a throttle cable or a link mechanism connected to the accelerator pedal. There is a mechanical method that opens and closes the throttle valve, and an electrical method that converts the amount of depression of the accelerator pedal into an electrical signal and uses a motor to control the opening and closing of the throttle valve in response to this electrical signal. In the method of mechanically opening/closing the throttle valve or the method of electrically controlling the opening/closing of the throttle valve, the throttle valve is adjusted to keep the engine operating in a stable state that matches the engine characteristics during warm-up or idling during operation. It is necessary to minutely control the opening degree. Furthermore, when the accelerator pedal is depressed at high speed during accelerator operation, the opening speed of the throttle valve must also be made to correspond immediately to the depression speed of the accelerator pedal. As described above, when the engine is idling, it is necessary to minutely control the throttle valve, and when the engine is accelerating, it is necessary to control the throttle valve by a relatively large amount of displacement at high speed. In order to satisfy these conflicting control demands, conventionally it was necessary to separately install an actuator to minutely control the opening of the throttle valve when the engine was idling, and the space required to install the actuator separately was required. It had the disadvantage of requiring an extra amount of

(Purpose of the invention) The present invention provides an engine throttle valve control device that changes the step angle of the step motor in place of the phase excitation method of the step motor when opening and closing the engine throttle valve using a step motor. Accordingly, it is possible to control the opening and closing of a throttle valve to match idling characteristics or accelerator characteristics only by controlling a step motor.

(Structure of the invention) As shown in FIG. 1, the present invention includes a step motor 2 for controlling the opening and closing of a throttle valve 1 of an engine, and a torque transmission system for transmitting rotational torque of the step motor 2 to the throttle valve 1. Device 3
, an accelerator sensor 5 that generates an output signal corresponding to the amount of depression of the accelerator pedal 4, an engine sensor 6 that generates an output signal that corresponds to the operating state of the engine, and according to the output signals of the accelerator sensor 5 and the engine sensor 6. An engine throttle valve control device comprising an electric control circuit 7 that outputs a predetermined number of pulse signals to a step motor 2 and changes the step angle by switching the phase excitation method of the step motor 2 according to the operating state of the engine. be.

(Embodiment of the invention) The configuration of an embodiment of the invention will be explained with reference to FIGS. 2 to 4. In FIG. 2, the throttle valve 12 fixed to the throttle shaft 11 is biased in the closing direction by the force of the throttle back spring 13, and the gears 15, 16, 17, 18 are rotated by the rotational torque output from the step motor 14. Opening/closing is controlled by rotating the throttle shaft 11 via a speed reducer formed by the throttle shaft 11.

The step motor 14 includes an accelerator sensor 18 that generates an output signal corresponding to the amount of depression of the accelerator pedal 17 after the ignition switch 15 is turned on and power is supplied from the battery 16;
A temperature sensor 20 that generates an output signal corresponding to the temperature of the engine cooling water in the water jacket 19.
The step motor is activated in response to signals output from the ignition coil 21, which generates a trigger signal in accordance with the engine speed, the cooler input switch 22, and the electric load input switch 23, such as a power steering switch. The drive is controlled by an electric control circuit 24 which outputs 14 drive signals.

FIG. 3 shows an outline of the structure of the step motor 14. The step motor 14 includes a rotor 33 fixed to an output shaft 31 and having a large number of evenly spaced small teeth 32 on the outer periphery, and a winding 34 on the inner periphery. This is a four-phase step motor having eight wound large teeth 35 and a stator 37 in which each large tooth 35 has four small teeth 36.

FIG. 4 is a block diagram of the electric control circuit 24. When the ignition switch 15 is turned on and power is supplied from the battery 16 to the electric control circuit 24, the power supply circuit 41 determines the supplied battery power. Convert to voltage stabilized power supply and electrical control circuit 24
The microcomputer CPU supplies the required voltage to each circuit, and the microcomputer CPU controls the accelerator sensor 18, engine coolant temperature sensor 20, ignition coil 21, and cooler input switch 22 according to the control program built in the memory circuit ROM. , calculates the number of pulses to be output to the step motor 14 according to the output signal of the electric load input switch 23 such as power steering, and generates a pulse signal corresponding to the calculated number of pulses together with the phase excitation signal of the step motor 14. The signal is output to the motor drive circuit 43 via the I/O port 42, converted into a drive signal by the motor drive circuit 43, and then output to the step motor 14.

The trigger output signal of the ignition coil 21 is shaped by the waveform shaping circuit 44 and then input to the microcomputer CPU.
Since the output signals of 8 and the cooling water temperature sensor 20 are analog signals, they are converted into digital signals by the A-D converter circuit 45, and then input to the microcomputer CPU via the I/O port 46, and then input to the cooler input switch 22. Since the output signal of the electric load input switch 23 such as power steering is a digital signal, it is inputted to the microcomputer CPU via the I/O port 46 without signal conversion.

(Operation of this embodiment) Next, the operation of this embodiment will be explained with reference to FIGS. 5 to 7. In step 101 of the excitation method determination routine for the step motor 14 in FIG.
is turned on and power is supplied from the battery 16, and when the engine is running, the accelerator pedal 17 is activated by the output signal of the accelerator sensor 18.
If it is determined that the accelerator pedal 17 is depressed, step 1 is performed as accelerator control.
If it is determined that the accelerator pedal 17 is released, idle control is performed in step 102. In step 102, the electric control circuit 24 determines the engine target according to the output signals of the temperature sensor 20, which generates an output signal corresponding to the engine cooling water temperature, the cooler input switch 22, and the electric load input switch 23 for power steering, etc. In addition to setting the idle speed,
The endon operating speed signal output from the ignition coil 21 is input and compared with the target idle speed of the engine, and in the next step 103, it is determined whether the engine operating speed and the target idle speed match. If they match, it is determined that the idle control is being performed properly and other engine control processing is performed, and if they do not match, step 10 is performed.
4, a step motor 1 for correcting the opening degree of the throttle valve 12 corresponding to the deviation rotation speed;
After calculating the number of drive steps in step 4, step 10
In step 5, it is necessary to minutely control the opening degree of the throttle valve 12 in order to bring the engine operation into a stable state that matches the engine characteristics during warm-up or idling during operation.
Therefore, a 1-2 phase excitation signal for reducing the step angle of the step motor 14 and a pulse signal corresponding to the number of drive steps are sent to the motor drive circuit 43.
In step 106, the motor drive circuit 43 converts the 1-2 phase excitation signal and pulse signal in step 105 into a drive pulse signal, and then outputs it to the step motor 14 to drive the step motor 14 and operate the throttle valve 12. By correcting the opening degree of the throttle valve 12, the throttle valve 12 is minutely controlled, and the engine operating state during idling can be stabilized.

FIG. 6 shows the progress of the rotor 33 when the drive pulse signal is input during 1-2 phase excitation of the step motor 14.
When the drive pulse signal 1p is input, the first phase 1s of the step motor 14 is excited, and the small teeth 32 of the rotor 33 are stepped by 1/8 tooth pitch from the position before the first drive pulse signal 1p was input. , when the second drive pulse signal 2p is input to the step motor 14, the first phase 1s and the second phase 2s are excited, and the step position of the small tooth 32 of the rotor 33 is the same as after the input of the first drive pulse signal 1p. When the position is advanced by 1/8 tooth pitch and the third drive pulse signal 3p is input, the first phase is 1s.
is de-energized and the second phase 2s becomes excited, the small teeth 32 of the rotor 33 further advance by 1/8 tooth pitch, and when the fourth drive pulse signal 4p is input, the second phase 2s becomes excited. The third phase 3p is excited and further 1/
The small teeth 32 of the rotor 33, to which eight drive pulse signals are input to the step motor 14, move in steps of one tooth.

If the electric control circuit 24 determines that accelerator control is to be performed based on the output signal of the accelerator sensor 18 in step 101, which determines whether the accelerator pedal 17 is in the depressed or released state, the control system performs accelerator control in step 107, and the accelerator sensor 18 and calculates the number of drive steps corresponding to the drive amount of the step motor 14 corresponding to the output signal of the accelerator sensor 18 in step 108. It is necessary to increase the opening speed of the throttle valve 12, and in step 109, a two-phase excitation signal for increasing the step angle of the step motor 14 and a pulse signal corresponding to the number of drive steps are output to the motor drive circuit 43. Then, in step 110, the motor drive circuit 43 converts the two-phase excitation signal and pulse signal in step 109 into a drive signal and outputs it to the step motor 14, so that the opening degree of the throttle valve 12 is determined by the output signal of the accelerator sensor 18. Step motor 14 until reaching the target opening corresponding to
is driven at high speed with two-phase excitation.

FIG. 7 shows the stepping state of the rotor 33 when the drive pulse signal is input during two-phase excitation of the step motor 14. When the first drive pulse signal 1p is input to the step motor 14, the first phase 1s and The second phase 2s is excited, the small teeth 32 of the rotor 33 advance by 1/4 tooth pitch from the position before the first drive pulse signal 1p was input, and the second drive pulse signal 2p is input to the step motor 14. 2nd phase 2
s and the third phase 3s are excited and the small teeth 3 of the rotor 33
The position 2 is advanced by 1/4 tooth pitch from the position after the input of the first drive pulse signal 1p, and when the third drive pulse signal 3p is input, the third phase 3s and the fourth phase 4s are excited and the rotor is rotated. The position of small tooth 32 of 33 is further 1/
When four drive pulse signals are inputted to the step motor 14 so as to advance by a pitch of four teeth, the small teeth 32 of the rotor 33 advance by a pitch of one tooth.

As mentioned above, when the engine is idling, it is necessary to minutely control the opening degree of the throttle valve 12 in order to keep the engine operating in a stable state that matches the engine characteristics. The step motor 14 is driven by a two-phase excitation method, and when accelerating, it is necessary to increase the opening speed of the throttle valve 12 in order to follow the depression speed of the accelerator pedal 17. Therefore, the step angle of the step motor 14 is increased. By driving the step motor 14 using a two-phase excitation method, the throttle valve 12 can be controlled to match the engine characteristics both during idling and when accelerating, without using any other special equipment.

(Effects of the invention) When controlling the opening and closing of an engine throttle valve using a step motor, the present invention replaces the phase excitation method of the step motor and changes the step angle of the step motor. There is an effect that the opening/closing can be controlled to match the idling characteristics or the accelerator characteristics by only controlling the above.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram that clearly shows the configuration of the present invention.
Figure 3 is an explanatory diagram of an embodiment of the present invention, Figure 3 is a structural diagram of its step motor, Figure 4 is its electric control circuit block diagram, Figure 5 is its control flowchart, and Figure 6 is its control flowchart. FIG. 7 is an explanatory diagram of the step of the rotor in the 1-2 phase excitation method of the step motor. FIG. 7 is an explanatory diagram of the step of the rotor in the 2-phase excitation method of the step motor. DESCRIPTION OF SYMBOLS 1... Throttle valve, 2... Step motor, 3... Torque transmission device, 4... Accelerator pedal, 5... Accelerator sensor, 6... Engine sensor, 7... Electric control circuit.

Claims (1)

[Scope of utility model registration request] A step motor for controlling the opening and closing of the throttle valve of the engine, a torque transmission device for transmitting the rotational torque of the step motor to the throttle valve, and an accelerator sensor that generates an output signal corresponding to the amount of depression of the accelerator pedal. an engine sensor that generates an output signal corresponding to the operating state of the engine; and an engine sensor that outputs a number of pulse signals determined according to the output signals of the accelerator sensor and the engine sensor to the step motor, A throttle valve control device for an engine, comprising: an electric control circuit for changing a step angle by switching a phase excitation method of the step motor.