JPS59131737A - Apparatus for controlling throttle valve - Google Patents

Abstract

PURPOSE:To prevent the occurrence of accidents, by controlling the opening of a throttle valve of an internal combustion engine by means of a spring for energizing the throttle valve in the valve closing direction and an AC motor for driving the throttle valve in the valve opening direction, thus simplifying the valve opening and closing mechanism, and enabling to close the throttle valve even if trouble is caused with the motor or other. CONSTITUTION:A shaft 12 of a throttle valve 11 disposed in a carburetor or the throttle body of an intake pipe is provided with a return spring for urging the valve 11 in the valve closing direction. Further, an AC motor 13 is connected directly to one end of the shaft 12 while a potentiometer 14 is connected to the other end of the shaft 12. In a comparator 20, comparison is made between the output signal of a valve opening setter 22 and the valve opening signal given from the potentiometer 14. Only when the set value of the setter 22 is greater, the throttle valve 11 is opened by turning a transistor 26 ON and energizing field coils SL1-SL4 of the motor 13 successively in response to the output signal of a logical circuit 40. In case that a trouble is caused with the motor or the like, the throttle valve 11 is closed swiftly by means of the return spring, so that it is enabled to prevent uncontrollable operation of an engine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle control device, and more particularly to a linkless throttle control device that electrically controls throttle opening.

Linkless throttle control device that electrically controls throttle opening! Since t can respond not only to accelerator pedal depression -I but also to various factors such as the engine driving state, its adoption is increasing.

However, since the throttle valve drive mechanism of conventional linkless throttle control devices is composed of a forward-reverse DC motor and gears, parts such as brushes often fail, and when a failure occurs, the throttle valve stops with the valve open. There is also the problem of doing so.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to improve the reliability of a linkless throttle control system and to provide a throttle control system in which the throttle valve closes quickly in the event of a failure. That is, the throttle control device according to the present invention includes: an AC motor that drives a throttle valve of an internal combustion engine in a direction to open it; a return spring that operates in a direction to close the throttle valve; and a sensor that detects the throttle opening degree.
It consists of an AC generating device that compares and calculates the output signal from the sensor and a throttle signal indicating a desired throttle opening to control the torque of the motor. The AC motor is rotatably connected to the throttle valve without going through a gear mechanism (especially directly connected)
It is preferable to use a synchronous motor, an induction motor, etc.

In addition, when a DC motor is used, there is a drawback that the return spring cannot easily return to the closed position due to the resistance caused by the brushes, and the drawback of brush wear cannot be overcome.

The sensor that detects the throttle opening is composed of, for example, a potentiometer connected to the shaft of the throttle valve, and the throttle opening is converted into a resistance value or voltage r.The AC generator generates pulses that generate a rotating magnetic field of the AC motor. an AC generating circuit that generates an AC frequency; a comparison circuit that compares a signal indicating the throttle opening degree from the sensor with a signal indicating the desired opening degree; An AC circuit generally consists of a clock generation circuit, a logic circuit that is controlled based on the circuit quantity, and a switching circuit that turns on and off the motor field current based on the logic circuit.
It will be blown away.

In the throttle control device i having the above configuration, when the actual opening is smaller than the desired opening, the output of the comparator increases and the control circuit increases the excitation current or decreases the number of rotations. This increases the motor rotation torque. Accordingly, the motor rotates in one direction against the return spring, and rotates the throttle valve at the desired opening degree of 1. Once the desired opening is reached, the comparator applies a current or frequency I3. to maintain the throttle valve in that position. hold.

In this way, the desired opening degree can be obtained at the point where the motor torque and the return spring force match, but if rotational torque cannot be obtained due to a failure of the motor, for example, the throttle valve is quickly opened by the biasing force of the return spring. By closing, the vehicle can also be stopped.

That is, the throttle control device of the present invention has the advantage that reliability is improved because sliding wear parts such as brushes are not used, and the throttle is quickly closed in the event of a failure. However, the device can be sufficiently miniaturized and the mechanical structure can be simplified.

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

In FIG. 1, a throttle valve 11 disposed in a throttle body 10 of a carburetor or electronic fuel injection controlled vehicle is fixed to a shaft 12 passing through the body 10, and is attached to both ends of the shaft 12 (1. The shafts of an AC motor 13 and a potentiometer 14 are connected directly to each other.These shafts 11,
13a, 14aIli are rotatable with respect to the throttle body 10, but are always kept close to the throttle valve 10 by a return spring 15 provided on the outer periphery of the shaft 12.
Torque is applied to close it.

Terminal 14 of potentiometer 14 as shown in FIG.
A stabilized voltage Vcc (5V) is applied between a and 14C via a three-terminal regulator 16,
Since the slider 17 is interlocked with the shaft 12, the terminal 14
A voltage vj proportional to the throttle opening is generated at b. This voltage is applied to the inverting input terminal (-) of the operational amplifier 20 via the resistor 18.

A throttle signal voltage 2 proportional to a desired throttle opening degree divided by a non-inverting input terminal (+) KH of the operational amplifier 20, a semi-variable resistor 21, and a potentiometer 22 is applied via a resistor 23.

A resistor 24 is connected between the inverting input terminal (-) and the output terminal of the operational amplifier 20, and the operational amplifier 20 functions as a differential amplifier, and the voltage from the potentiometer 14 is
Difference between l and voltage V2 from potentiometer 23 V2 - V
, outputs a voltage proportional to .

The output terminal of the operational amplifier 20 is connected to the base of a transistor 26 via a resistor 25, and the collector current Ic of the transistor 26 is controlled by the output voltage. That is, the current Ic is controlled in response to the difference between the desired throttle opening and the actual throttle opening.

Next, the rotating magnetic field generating current generating circuit located in the upper part of FIG. 2 will be explained. This circuit includes a clock signal generator 30, a logic circuit 40 composed of a pair of Noritsu flops 41 and 42, and four pairs of switching circuits S Wl.
-'-" 8W4.

The clock signal generator 30 is a circuit for generating a clock signal of about 100I-12, and is composed of a circuit vr31 containing 5 ICs and a CR circuit.

The clock signal from the clock signal generator 30 is applied to the clock terminals CK of the two flip-flops 7'41, 42,
and CR2 simultaneously. each flip-flop 4
The stabilized voltage Vcc (5V
) is applied. The data input terminal and output terminal Q of the first flip-flop 41 are connected to the output terminal q and the data input terminal D2 of the second flip-flop 42, respectively.

Therefore, each output terminal Q, , Q, 2. Q2 and Ql
lines 4 + Z2) connected respectively to t3 +
74, . . . high level voltage and low level voltage are generated alternately.

Each of the switching circuits SW1 to SW4 connected to the output terminals of the flip-flops 41 and 42 through lines t1 to t and resistors R and R4k is composed of two Darlington-connected transistors, and has a collector and a The field coil SLl of the AC motor 13 is connected to the power source.
SL4 is connected to each transistor, and a protection diode is connected between the collector and emitter of each transistor to prevent the transistor from being destroyed by back electromotive force. The emitters of the switching circuits SW1 to SW4 are connected to each other and to the collector of the current control transistor 26 described above.

Therefore, the switching circuits swl and sw4 are alternately turned on while the transistor 26 is conductive.

0FFI is repeated, and the field coils SLl to SL4 alternately (
In this case, every other motor is excited, and a rotating magnetic field is generated within the AC motor 13.

While the rotating magnetic field is generated in this manner, as described above, the collector current of the transistor 26 is controlled to perform shimor rotation torque control, thereby obtaining a desired throttle opening degree.

In this example, the desired throttle signal is generated by a unique variable resistor 2.
Although it is set by the adjustment in step 2, it can also be obtained as a controlled value by other methods, for example by a microcomputer that responds to engine operating conditions, driving conditions, etc. to obtain the home throttle signal. be able to.

The embodiment shown in the block circuit diagram of FIG. 3 controls the drive torque of the motor by changing the frequency. For example, in FIG. 2, by V/F converting the output f of the output terminal of the operational amplifier 20, the corresponding frequency is applied to the motor drive circuit 16.

As the motor drive circuit, for example, FIG. 2 is a side sectional view showing a throttle valve drive mechanism, FIG. 2 is a circuit diagram showing a throttle control system of the present invention, and FIG. 3 is a block circuit of another embodiment. It is a diagram.

10-Throttle body 11-Throttle valve 13-AC motor 14--Potentiometer 20-Amp 26-Current control transistor 30-Clock signal generator 41.42-7 ring 70 Tsug SW, ~5W4-Switching circuit Questioner: Aisin Nki Co., Ltd. Agent: Patent Attorney Ka Michi Fuji =277

Claims (1)

[Claims] An AC motor that drives the throttle valve of an internal combustion engine in the direction to open it, a return spring that operates in the direction to close the throttle valve, a sensor that detects the full throttle opening, and an output signal from the sensor and displays the desired throttle opening. an alternating current generator that controls the torque of the motor by comparing and calculating the torque of the motor with a throttle signal.