JPH0264238A - Device for controlling throttle valve of internal combustion engine - Google Patents

Abstract

PURPOSE:To make it possible to control a throttle valve with sufficient responsiveness and accuracy by interposing a pressure regulator for a circuit through which negative pressure is introduced into a diaphragm type actuator equipped with a stopper connected with a motor. CONSTITUTION:A diaphragm type actuator 12 is provided with a stopper 15 which is supported by a casing 9 in such a way as to be freely advanced and/or retreated while its one end faced onto the negative chamber 10 side of a diaphragm 8 can be brought in contact with. And a solenoid valve 14 is interposed between a pressure regulator 13 and the negative pressure chamber 10 so that duty control is performed by a control means 6. This situation permits the pressure regulator 13 to stabilize negative pressure to be introduced into the negative pressure chamber 10 regardless of the fluctuation in the operating conditions of an engine, the diaphragm type actuator 12 can thereby be accurately actuated by the duty control of the solenoid valve 14 so that the opening of the throttle valve 4 can be controlled with sufficient responsiveness and accuracy. In addition, when the stopper 15 is driven by a motor 16 so as to be advanced and/or retreated, the opening for an idle operation can be adjusted in a stepless manner.

Description

Detailed Description of the Invention A1 Objective of the Invention (1) Industrial Application Field The present invention relates to a control means for outputting a control signal according to the operating state of an engine, and a throttle valve disposed in the middle of an intake passage. The present invention relates to a throttle control device for an internal combustion engine, which includes a drive means that is interlocked and connected to and operates in accordance with the output of the control means.

(2) Conventional technology Conventionally, such a throttle control device performs duty control between the negative pressure in a negative pressure chamber in a diaphragm actuator connected to a throttle valve and the intake passage downstream of the throttle valve. A type with a solenoid valve interposed therein, and a type with a throttle valve connected to a step motor or a servo motor (for example, Japanese Patent Application Laid-Open No. 61-291747)
Publication No.) etc. are known.

(3) Problems to be Solved by the Invention However, among the above-mentioned conventional technologies, those using diaphragm actuators have difficulty controlling the solenoid valve duty in response to fluctuations in intake negative pressure, resulting in overshoot. The responsiveness of throttle control may deteriorate. In particular, when the engine returns from a transient state to an idle state, responsiveness deteriorates in response to hunting in the engine speed. Furthermore, in the method disclosed in JP-A No. 61-291747, since the rotation of the motor is converted into the forward and backward movement of the actuator, it cannot be said that the response is excellent, and the problem is that the motor becomes larger. There is.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a throttle control device for an internal combustion engine that can control a throttle valve with good responsiveness and accuracy.

B1 Structure of the Invention (1) Means for Solving the Problems The present invention provides a control means that outputs a control signal according to the operating state of the engine, and a throttle valve disposed in the middle of an intake passage. and a drive means that operates according to the output of the control means. ! In the throttle control device for engine A, the driving means includes a diaphragm actuator whose casing is divided into a negative pressure chamber and an atmospheric pressure chamber by a diaphragm connected to the throttle valve, and a a pressure regulator connected to the intake passage, a solenoid valve interposed between the pressure regulator and the negative pressure chamber and whose duty is controlled by the control means, and one end of the diaphragm facing the negative pressure chamber side. It is characterized by comprising a stopper that is able to come into contact with the casing and is supported in a movable manner on the casing, and a motor that is connected to a control means and connected to the stopper so as to be controlled in operation.

(2) Effect According to the above configuration, the negative pressure to be introduced into the diaphragm actuator is stabilized by the pressure regulator regardless of fluctuations in the operating state of the engine, and therefore the diaphragm actuator can be operated accurately by controlling the duty of the solenoid valve. This makes it possible to precisely control the opening of the throttle valve. Moreover, since the throttle valve is driven in response to the displacement of the diaphragm in response to pressure changes in the negative pressure chamber, responsiveness is improved. Furthermore, by driving the stopper forward and backward with the motor, it becomes possible to adjust steplessly the maximum displacement position of the diaphragm toward the negative pressure chamber, that is, the idle opening degree of the throttle valve.

(3) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. An intake pipe l connected to an engine main body (not shown) and a throttle body 2 connected to the upstream end of the intake pipe l are An intake passage 3 for supplying air to the engine body is formed, and a throttle valve 4 is pivotally supported on the throttle body 2 via a throttle shaft 5 to open and close the intake passage 3.

This throttle valve 4 is operated in conjunction with an accelerator pedal (not shown). and is connected to a drive means 7 whose operation is controlled by a control means 6 consisting of a computer or the like,
The throttle valve 4 is rotationally driven in response to the depression operation of the accelerator pedal, and the opening degree of the throttle valve 4 is determined in accordance with the operation of the driving means 7 regardless of the accelerator pedal, and the opening degree of the throttle valve 4 is determined depending on the operation of the driving means 7 regardless of the accelerator pedal. The degree is determined by the drive means 7. The driving means 7 includes a diaphragm actuator 12 in which the inside of the casing 9 is divided into a negative pressure chamber 1O and an atmospheric pressure chamber 11 by a diaphragm 8 connected to the throttle valve 4, and an intake air valve located downstream of the throttle valve 4. A pressure regulator 13 connected to the passage 3, a solenoid valve 14 interposed between the pressure regulator 13 and the negative positive chamber 10 and whose duty is controlled by the control means 6, and a maximum pressure of the diaphragm 8 to the negative pressure chamber lO side A stopper 15 for determining a displacement position and a motor 16 such as a step motor or a servomorph for driving the stopper 15 are provided.

The throttle valve 4, that is, the throttle shaft 5, is urged to rotate in the closing direction of the throttle valve 4 by a spring (not shown). A throttle lever 26 is rotatably supported at one end of the throttle shaft 5 protruding from the throttle body 2, and an accelerator pedal ear 27 is attached to the throttle lever 26 to move the throttle lever 26 in the valve opening direction when the throttle lever 26 is pulled. They are connected for rotation. Moreover, a low motion spring (not shown) is interposed between the throttle lever 26 and the throttle shaft 5, and the throttle lever 26
6, the throttle shaft 5, that is, the throttle valve 4 rotates. A lever 17 is fixed to the other end of the throttle lever protruding from the throttle body 2, and a control lever 19 having a threaded member 18 that can abut and press the lever 17 controls the lever 17 by the threaded member 18. It is rotatably supported so as not to push the valve 4 in the opening direction. The screw member 18 is screwed into the control lever 19 so that it can move forward and backward, and by adjusting the forward and backward positions of the screw member 18, the relative positions of the lever 17 and the control lever 19 can be adjusted.

The diaphragm actuator 12 includes a casing 9, a diaphragm 8 whose peripheral edge is sandwiched between the casing 9 and which partitions the inside of the casing 9 into a negative pressure chamber 1O and an atmospheric pressure chamber 11, and a direction in which the volume of the negative pressure chamber 10 is increased. diaphragm 8 and casing 9 in order to bias the diaphragm 8
A spring 20 is interposed therebetween, and one end is connected to the center of the diaphragm 8 and the atmospheric pressure chamber 11 of the casing 9.
A drive shaft 1"2 that passes through the part facing the axially movably
1, and the other end of the driving iron 2I is connected to the control lever 19. In such a diaphragm actuator 12, as negative pressure is introduced into the negative pressure chamber 10, the diaphragm 8 is displaced in a direction that contracts the volume of the negative pressure chamber 10 against the spring force of the spring 20. The lever 17 is driven to rotate via the control lever 19 by the axial movement of the drive rod 21 accompanying the displacement, and the throttle valve 4 is driven in the valve opening direction.

The stopper 15 is formed into a rod shape, and is movable in the axial direction so that one end can come into contact with the central part of the diaphragm 8 on the side of the negative pressure chamber 10, and is attached to the casing 9 so as to keep the negative pressure chamber 10 airtight. Supported. Furthermore, rotation of the stopper 15 around the axis is prevented. Further, the motor 16 is
It is connected to the control means 6 and attached to the casing 9 of the diaphragm actuator 12 so as to be operated by a control signal from the control means 6 . The rotating body 16a of the motor 16 is screwed to the other end of the stopper 15, and the stopper 15 moves forward and backward in the axial direction in response to the rotation of the motor 16.

A connecting pipe portion 25 is provided in the intake pipe 1 to take out the negative intake pressure downstream of the throttle valve 4 in the intake passage 3, and one end of the pressure regulator 13 is connected to the connecting pipe portion 25.
connected to. This pressure regulator 13 has a conventionally well-known structure, and functions to adjust the intake negative pressure taken out from the connecting pipe portion 25 to a substantially constant level.

The solenoid valve 14 is in a state in which the pressure regulator 13 is communicated with the negative pressure chamber IO of the diaphragm actuator 12 when the solenoid 14a is demagnetized, and in a state in which the negative pressure chamber 10 is opened to the atmosphere when the solenoid 14a is in the energized state. The solenoid 14a is duty-controlled by the control means 6. The duty control of the solenoid valve 14 determines the negative pressure in the negative pressure chamber 10 in the diaphragm actuator 12, and the opening degree of the throttle valve 4 is determined accordingly.

Next, to explain the operation of this embodiment, the intake negative pressure on the downstream side of the throttle valve 4 is regulated almost constant by the pressure regulator 13 and introduced into the negative pressure chamber 10 of the diaphragm actuator 12. The negative pressure to be introduced into the negative pressure chamber 10 of the diaphragm actuator I2 is stabilized regardless of fluctuations in the operating state of the engine. Therefore, by controlling the duty of the solenoid valve 14, it is possible to accurately operate the diaphragm actuator 12 and precisely control the opening degree of the throttle valve 4.

In addition, the displacement of the diaphragm 8 in response to pressure changes in the n-pressure chambers 1 and 0 is caused by the drive rod 21, control lever 19, screw member 1
Since the rotation of the throttle valve 4 is changed via B and the lever 17, the throttle valve 4 is immediately driven by the operation of the diaphragm actuator 12, improving responsiveness.

Furthermore, since the maximum displacement position of the diaphragm 8 toward the negative pressure chamber 10 is controlled by the stopper 15 which is driven forward and backward by the motor 16, the operating amount of the motor 16 can be controlled steplessly by the control means 6. It becomes possible to control the idle opening degree of the throttle valve 4 steplessly, and the marketability is improved. Moreover, since the negative pressure introduced into the negative pressure chamber 10 is stable, there is no need to unnecessarily increase the size of the motor 16 that supports the stopper 15 that regulates the displacement of the diaphragm 8, and the motor 16 can also be made smaller. It's just a thing.

C8 Effects of the Invention As described above, according to the present invention, the driving means includes a diaphragm actuator in which the inside of the casing is divided into a negative pressure chamber and an atmospheric pressure chamber by a diaphragm connected to the throttle valve; a pressure regulator connected to the intake passage on the downstream side; a solenoid valve interposed between the pressure regulator and the negative pressure chamber and whose duty is controlled by the control means; and a solenoid valve facing the negative pressure chamber side of the diaphragm. The stopper is supported on the casing so as to be able to move forward and backward with one end thereof being able to come into contact with a surface, and the motor is connected to a control means and connected to the stopper to control its operation, so that it can be introduced into a diaphragm actuator. By stabilizing the negative pressure to be generated, the diaphragm actuator can be operated accurately, and the opening of the throttle valve can be precisely controlled. Furthermore, the stopper that regulates the maximum displacement of the diaphragm toward the negative pressure chamber is driven forward and backward by the motor, making it possible to steplessly control the idle opening of the throttle valve. Miniaturized.

[Brief explanation of the drawing]

The drawing is an explanatory diagram of an embodiment of the present invention. 93...Intake passage, 4...Throttle valve, 6...Control means, 7...
... Drive means, 8... Diaphragm, 9... Casing, 10... Negative pressure chamber, 11... Atmospheric pressure chamber, 12...
...Diaphragm actuator, 13...Pressure regulator, 14...Solenoid valve, 15...Stopper, 16...Motor Honda Motor Co., Ltd. Ken Ochiai 1) Takahide Naka

Claims (1)

[Claims] An internal combustion engine comprising a control means that outputs a control signal according to the operating state of the engine, and a drive means that is interlocked and connected to a throttle valve disposed in the middle of an intake passage and operates according to the output of the control means. In an engine throttle control device, the driving means includes a diaphragm actuator whose casing is divided into a negative pressure chamber and an atmospheric pressure chamber by a diaphragm connected to the throttle valve, and a diaphragm actuator connected to the throttle valve and connected to the intake passage downstream of the throttle valve. a pressure regulator to be connected, a solenoid valve interposed between the pressure regulator and the negative pressure chamber and whose duty is controlled by the control means, and one end of which can be brought into contact with a surface of the diaphragm facing the negative pressure chamber side. 1. A throttle control device for an internal combustion engine, comprising: a stopper supported by the casing so as to be movable forward and backward; and a motor connected to a control means and connected to the stopper for operation control.