JPH08193528A - Intake air quantity controller of engine - Google Patents

Abstract

PURPOSE: To aim at the promotion of miniatrization, lightweightiness, structural simplification and cost reduction as a whole by opening or closing a control valve in an idling bypass and a throttle valve in an intake pipe and driving them with one electric motor. CONSTITUTION: A valve element 17 of a control valve 15 in a bypass 4 is installed in an output shaft 12 of an electric motor 11, making it control an idling air quantity, and a valve stem 7 of a throttle valve 6 in an intake pipe 1 is connected to the output shaft 12 through a connecting-intercepting means 21 to be turned to connectivity in time of off-idling, and thereby engine output power is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling the intake air amount for controlling the output of an engine, and more particularly to a device for controlling the intake air amount by driving a throttle valve with an electric motor.

[0002]

2. Description of the Related Art In order to meet demands for improved running performance, regulation of exhaust gas and reduction of fuel consumption for automobiles, a throttle valve for controlling intake of an engine is driven by an electric motor in addition to or in place of foot-operated manual operation. Technology has been developed (JP-A-60-240835, JP-A-62-28).
2146, Japanese Patent Laid-Open No. 1-117944).

On the other hand, since the intake pipe for supplying air to the engine has a considerably large diameter in a large displacement engine, the throttle valve, which is generally a butterfly valve, is also large and therefore opens in the low opening range. The intake air amount greatly changes with a slight change in the angle, and the intake air amount cannot be precisely controlled.

Therefore, as disclosed in Japanese Patent Laid-Open No. 51-2834, a bypass is connected downstream of the throttle valve of the intake pipe, and a control valve is installed in this bypass to reduce the amount of intake air. It is preferable to perform engine speed control during idling, which is a region. In this case, the control valve is driven by an actuator that operates according to the engine operating state, generally an electric motor.

[0005]

As described above, in the case where the throttle valve of the intake pipe is driven by an electric motor and a bypass in which a control valve for driving the electric motor is installed for controlling the engine speed during idling is provided, Since electric motors are prepared separately for both the valve and control valve, not only inevitably the mechanism for controlling the intake amount becomes larger and heavier, but at the same time expensive, it is also electronically controlled. A circuit for sending a drive signal from the unit to each electric motor and wiring are required separately, so it cannot be complicated.

In view of the above, the present invention solves the above-mentioned problems caused by the configuration in which the throttle valve of the intake pipe and the control valve of the bypass valve are driven by separate electric motors, and performs stable idle control in terms of function. Of course, it is an object of the present invention to provide a low-cost intake air amount control device which is small and lightweight, has a complicated structure, and is inexpensive.

[0007]

According to the present invention, a bypass opened and closed by a control valve is connected to a downstream side of a throttle valve of an intake pipe,
In an intake air amount control device for an engine in which a throttle valve is opened and closed by an electric motor that operates according to the operating state of the engine, a valve body of the control valve is provided on the output shaft of the electric motor, and the valve shaft of the throttle valve is connected. It has been decided to solve the above-mentioned problems with a configuration in which the output shaft can be connected or disconnected via a breaking mechanism.

It is preferable that the valve body of the control valve is formed at a portion that crosses the bypass of the output shaft and an air passage hole is provided therein, or the connecting / disconnecting mechanism is an electromagnetic clutch.

[0009]

[Operation] When idle, the connection / shutoff mechanism operates the electric motor with the valve shaft disconnected from the output shaft, controls the phase of the output shaft, and adjusts the amount of air flowing through the bypass by the control valve to control the engine speed. . During off / idle, the motor is operated with the valve shaft connected to the output shaft, and the amount of air flowing through the intake pipe is adjusted by the throttle valve. That is, connection
By operating the shutoff mechanism, the control valve for the bypass for idle and the throttle valve for the intake pipe are separately opened and closed by one electric motor.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. A throttle body 2 forming a part of an intake pipe 1 of an engine is provided with an intake passage 3 upstream and downstream of a throttle valve 6. A bypass 4 that communicates with each other is provided. The throttle valve 6 is a well-known butterfly valve including a valve shaft 7 rotatably installed on the throttle body 2 across the center of the intake passage 3 and a disc-shaped valve plate 8 fixed to the valve shaft 7. The open / close drive is performed by the electric motor 11 including a DC motor or a stepping motor.

The output shaft 12 of the electric motor 11 is made longer than usual, and its tip portion is rotatably movably installed through the valve casing 16 inserted in the bypass 4 in an airtight manner. The output shaft portion that crosses the bypass 4 forms a valve body 17 and has an air passage hole 18 that is a diametrical hole that connects the upstream side and the downstream side of the air passage 5. The valve casing 16 and the valve body 17 constitute the control valve 15.

On the other hand, the output shaft 12 has a disc-shaped clutch disc 22, and an electromagnetic coil 24 enclosed by a yoke 23 fixed to the housing 13 of the electric motor 11 and the output shaft 1
A clutch facing 26, which is fixed to a rotor 25 rotatably fitted to the rotor 2, is arranged with a clutch disc 22 interposed therebetween, and these constitute an electromagnetic clutch that is a connection / disconnection mechanism 21.

Further, a driving gear 32 formed on the rotor 25
The output shaft 12 by means of a gear transmission mechanism 31 including an intermediate gear 33 and a fan-shaped driven gear 34 fixed to the shaft end of the valve shaft 7.
Rotation is reduced and transmitted to the valve shaft 7. A control valve return spring 36 made of a spiral spring is attached to the shaft end of the output shaft 12, and a throttle valve return spring 37 made of a torsion coil spring is attached to the shaft end of the valve shaft 7.

In this embodiment having such a configuration, a drive signal corresponding to the engine operating state is sent from an electronic control unit (not shown) to the electric motor 11 and the connecting / disconnecting mechanism 21 to open / close the throttle valve 6 and the control valve 15. When the engine is started and the engine is idle, the electromagnetic coil 24 is not supplied with power. Therefore, the output shaft 12 and the rotor 25 are rotatable relative to each other. In this state, the throttle valve 6 has the return spring 3
The intake passage 3 is closed by the spring force of 7, and the output shaft 12 is rotated within a range of about 90 degrees to allow the air passage hole 1 to move.
8 adjusts the amount of air flowing through the air passage 5 between fully closed and fully opened, and performs engine speed control during idling.

The air passage hole 18 of the control valve 15 regulates the maximum air flow rate during idling, and acts as a variable throttle that changes the effective passage area according to the engine operating condition.

Further, since the required air amount of the engine at the time of idling is remarkably smaller than that at the time of normal operation, the bypass 4 may have a small diameter, and therefore the valve body 17 may be used as it is without the output shaft 12 having a particularly large diameter. Therefore, it is possible to control a small amount of air according to the rotation angle.

Further, the air passage 18 of this embodiment is the output shaft 1
2 has advantages that it can be easily formed by machining, and that the output valve 12 itself is used as the valve element 17, and the control valve 15 has a simple structure and can be manufactured at low cost. Of course, a butterfly valve similar to the throttle valve 6 may be used.

Next, at the time of idle, the electromagnetic coil 24
Power is supplied to the clutch disc 22, and the rotation of the output shaft 12 is transmitted to the valve shaft 7 via the connecting / disconnecting mechanism 21 and the gear transmission mechanism 31 to control the output by the throttle valve 6.

At this time, the control valve 15 opens and closes the bypass 4 according to the rotation of the output shaft 12, but the air flow rate of the bypass 4 is significantly smaller than the amount of air flowing through the intake pipe 1 during normal operation. Can be ignored.

In the present embodiment, the throttle valve 6 is driven to open and close only by the electric motor 11. However, the throttle valve 6 can be opened and closed by using a manual operation means by an accelerator pedal.
The present invention can also be applied to a control device that controls only the closing direction by 1 or a control device that can be opened and closed by the electric motor 11 regardless of the accelerator pedal. Further, when the manual operation means is also used, the movement thereof can be used to connect / disconnect the clutch, so that it is possible to use a mechanical clutch or coupling as the connecting / disconnecting mechanism 21. However, when the electromagnetic clutch is used as in this embodiment, the connection and disconnection can be performed by the electric drive signal, so that the structure is simple and the operation is reliable.

[0021]

As described above, the valve body of the control valve for opening and closing the idle bypass is provided on the output shaft of the electric motor, and the throttle valve is connected to the output shaft through the connecting / disconnecting mechanism which is in a connected state at the time of off / idle. According to the present invention, which is driven to open and close, not only can stable idle control be performed by using a bypass, but also the overall size reduction, weight reduction, and simplification of the structure can be achieved because there is only one electric motor. It can be provided at a low price.

[Brief description of drawings]

FIG. 1 is a sectional view showing the configuration of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX in FIG.

[Explanation of symbols]

1 intake pipe, 4 bypass, 6 throttle valve, 7 valve shaft, 1
1 electric motor, 12 output shafts, 15 control valves, 17 valve bodies, 18 air passage holes, 21 connection / disconnection mechanism

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location F02D 11/10 B H F02M 69/32

Claims (3)

[Claims] 1. An intake air amount control apparatus for an engine, wherein a bypass opened / closed by a control valve is connected to a downstream side of the throttle valve of an intake pipe, and the throttle valve is opened / closed by an electric motor which operates according to an engine operating state. An intake air amount control device, wherein the valve body of the control valve is provided on an output shaft of the electric motor, and the valve shaft of the throttle valve can be connected to and disconnected from the output shaft by a connecting / disconnecting mechanism. . 2. A valve body of the control valve is formed at a portion of the output shaft that crosses the bypass, and an air passage hole is provided at an output shaft portion that forms the valve body. Engine air intake control device. 3. The intake air amount control apparatus for an engine according to claim 1, wherein the connecting / disconnecting mechanism is an electromagnetic clutch.