JPS63150449A - Throttle valve control device for engine - Google Patents

Abstract

PURPOSE:To facilitate compensation of a throttle valve for a minimum necessary opening, by providing two energizing means, energizing the throttle valve in an opening and closing direction, and a driven means, driving the throttle valve by means of a drive force higher than the energizing force of each energizing means. CONSTITUTION:When a driver controls an accel pedal 5, an opening signal from an accel sensor 6 is inputted to a control device 7, and the control device 7 outputs the given number of pulses to run a motor 4. In which case, a throttle valve 2 and a lever 8 situated to a shaft 3 are rotated. In this case, a rotation amount of the throttle valve 2 is decreased to a value lower than a given amount, and since, even when a contact piece 8a of the lever 8 is brought into contact with an elastic member 9, the drive force of the motor 4 is high, the opening of the throttle valve 2 is regulatable against the elastic member 9. When the motor 4 is stopped, the resilient member 9 is pressed by the lever 8 through the force of a return spring 10, and the throttle valve 2 is held in a position allowing the throttle valve to be slightly opened than a full closed position.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a throttle valve that controls the opening degree of a throttle valve that adjusts the flow rate of combustion air supplied to an engine using an electrical signal that corresponds to at least an amount of accelerator. Regarding a control device.

[Conventional technology]

Generally, this type of device has a throttle valve installed in the intake pipe, an accelerator sensor that detects the amount of depression of the accelerator pedal operated by the driver and generates an electric signal, and a throttle valve that detects the amount of depression of the accelerator pedal operated by the driver and generates an electric signal. The throttle valve has a control device that calculates the opening amount of the throttle valve, and a drive motor that drives the throttle valve based on a signal from the control device so as to realize the opening amount.

In addition, a return spring is provided to mechanically bias the throttle valve in the closing direction, and when the engine stops or the motor is not driven due to a disconnection, etc., the throttle valve is biased in the closing direction to ensure safety. To ensure this, the throttle valve is fully closed. The throttle valve is held at the fully closed position until the motor is driven again, such as when starting the engine.

However, if the throttle valve remains fully closed as described above when the motor does not drive due to a failure, the engine can idle due to the air flowing through the passage that bypasses the throttle valve, but in the idling state, maintenance is not possible. It is difficult to transport cars to the factory. In addition, when the starter motor is started when the engine is started, the battery voltage drops, so sufficient current is not supplied to the throttle valve drive motor, making it impossible to open the throttle valve.
There was a problem in that the required amount of air was not supplied during startup.

For this reason, in Japanese Patent Application Laid-Open No. 60-230520, the engine stops and the ignition switch is turned off.
It is known to energize the motor control circuit for a predetermined period of time using a delay switch to drive the motor and move the throttle valve to a predetermined opening required for the next engine start.

[Problem that the invention seeks to solve]

However, with this configuration, even if the throttle valve is opened by a predetermined opening degree, if no current is applied to the motor, there will no longer be enough torque to hold the throttle valve in the closed position, and the throttle valve will be closed due to external disturbances after the engine has stopped. The degree of opening may change due to influence.

Furthermore, even if the motor has a built-in permanent magnet, its detent torque is very small and cannot suppress changes in opening due to throttle valve disturbances, so the throttle valve may not be opened to the required opening when restarting. However, there was a problem in that the engine could not be started, especially at low temperatures.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a throttle valve control device that can maintain a throttle valve opened to a predetermined degree when the driving means does not drive the throttle valve, such as when the engine is stopped.

[Means for solving problems]

Therefore, the throttle valve control device of the present invention includes: a first biasing device that mechanically biases the throttle valve in the closing direction; a second biasing device that mechanically biases the throttle valve in the opening direction; a driving means that has a larger driving force than the urging forces of the first and second urging means and drives the throttle valve in accordance with an electric signal, The balance position is set at a position where the throttle valve is opened by a predetermined amount.

[Effect]

As a result, during engine operation, the throttle valve is moved by the drive means in the opening and closing directions against the urging forces of the first and second urging means, thereby adjusting the flow rate of combustion air flowing in the intake pipe. can. Furthermore, when the driving force from the driving means is cut off, no matter which position the throttle valve is in, it immediately moves to a position where the urging forces of the first and twentieth urging means are balanced, and the throttle valve moves through the passage in the intake pipe. It will open a predetermined amount. Therefore, the throttle opening required to move the car when restarting the engine or in the event of a breakdown is compensated, and the position of the throttle valve at this time is controlled by the first and second biasing means, which open and close the throttle valve. Since it is maintained by balancing the biasing forces applied in both directions, even if a force due to disturbance or the like is applied to the throttle valve, the opening degree is less likely to fluctuate.

〔Example〕

An embodiment of the present invention will be described below.

In FIGS. 1 and 2, reference numeral 1 indicates an intake pipe of the engine. A throttle valve 2 is provided in the intake pipe 1 so as to be rotatable by a throttle shaft 3. The end of the throttle shaft 3 passes through the wall of the intake pipe 1 to connect a throttle drive motor 4 externally attached to the intake pipe 1.
It is installed on the rotating shaft of the The motor 4 is composed of a step motor, and similarly to the conventional device described above, determines the amount of rotation of the throttle valve 2 in accordance with a signal from an accelerator sensor 6, etc., which detects the amount of depression of the accelerator pedal 5 operated by the driver. It is driven by an electric signal from a control device 7 that controls the power supply.

The end of the throttle shaft 3 opposite to the motor 4 also passes through the wall of the intake pipe 1, and a lever 8 is inserted and fixed into this end. The lever 8 is the throttle shaft 3
A movable stopper and an abutment piece 8a extending parallel to the throttle shaft 3 toward the intake pipe 1 are formed at the end thereof. The side wall of the intake pipe l is formed with a side housing la that faces the contact piece 8a of the lever 8, and a screw 11 forming a fixed stopper is screwed into a screw hole provided in the side housing la. An elastic member 9 made of rubber or the like is fixed to the tip of the screw 11' that protrudes between the side housing 1a and the contact piece 8a, and this elastic member 9 is pressed by the contact piece 8a. It contracts and emits a repulsive force.

Further, a coil-shaped return spring 10 is provided on the outer periphery of the throttle shaft 3, and both ends thereof are fixed to the intake pipe 1 and the lever 8, respectively. In the closing direction of the throttle valve 2, that is, the abutment piece 8a is aligned with the elastic member 9.
The throttle valve 2 is biased in the direction in which the throttle valve 2 comes into contact with the throttle valve 2 (the direction indicated by the arrow in the figure).

Further, the position of the throttle valve when the contact piece 8a contacts the elastic member 9 is not fully closed, but is at an opening degree θ1 that slightly opens the intake passage 12.

Note that the torque generated by the motor 4 in the opening direction of the throttle valve 2 (the direction opposite to arrow A) is generated by the return spring 10.
Since the torque is set larger than the closing direction torque of the return spring 1, the throttle valve is
The throttle shaft 3 can be rotated against the urging force of 0.

In addition, the torque of the motor 4 in the throttle closing direction (direction of arrow A) is generated by contracting the elastic member 9 after the contact piece 8a of the lever 8 contacts the elastic member 9 and moving the throttle valve 2 to the fully closed position (throttle It has enough strength to rotate to the valve opening degree θ=O).

Next, the strength of the biasing force of the elastic member 9 and the biasing force of the return spring 10 at each throttle opening degree is determined by a third
This will be explained using figures.

In the graph of FIG. 3, the biasing force shown on the vertical axis is positive in the direction of closing the throttle valve 2 (direction of arrow A in FIG. 2) and negative in the opposite direction.

Further, the horizontal axis indicates the throttle opening degree θ. As described above, the return spring IO always biases the throttle valve 2 in the closing direction, and the biasing force increases in proportion to the throttle opening degree θ, as shown by the dotted line in the figure. Further, the elastic member 9 is configured such that the throttle opening θ is 0≦θ≦
Since it is pressed by the lever 8 when it is within the range of θ1, an urging force proportional to the throttle opening θ is generated only within that range as shown by the dashed line in the figure. Note that the elastic coefficient of the elastic member 9 is set larger than that of the return spring.

The biasing force of the return spring lO and the elastic member 9 at each throttle opening θ is as shown by the solid line. When θ≧01, the biasing force of the elastic member 9 is not applied, so the biasing force of the return spring 10 alone is Match the forces. When the throttle drive motor 4 is not driving the throttle valve 2, the lever 8 is urged in the closing direction by the return spring 10 and comes into contact with the elastic member 9. The position where the biasing forces are balanced, that is, θ=θ. The throttle opening is automatically adjusted mechanically. And this throttle opening θ. teeth,
The engine can be started reliably even at low temperatures, or even if an abnormality occurs in the electrical system of the motor 4, control means 7, etc. and the motor 4 no longer drives the throttle valve 2, it can be repaired to a repair shop. The opening is set to an opening (for example, θ = 5 to 6") that can secure the amount of intake air that enables the minimum necessary running condition for transporting the car. Also, this opening θ is determined by the throttle valve. 2, it is held by the urging force applied in both the opening and closing directions, so it is extremely unlikely to change even under the influence of external disturbances, and even if it does change, it will immediately return to its original state due to the elastic return force of the re-energizing means. The opening is restored.

Further, when the throttle opening degree θ is within the range of 0≦θ≦θ1, the elastic member 9 applies torque in the opening direction of the throttle valve 2. For example, when the throttle valve 2 is open, the motor 4 Alternatively, in the case where the control device 7 turns off the power to the motor 4 when a part of the control device 7 malfunctions, the throttle valve 2 is connected to the return spring 10.
However, when closing, when θ=θ1, the rotation of the lever 8 in the closing direction is absorbed by the elastic member 9, and the rotation of the throttle valve 2 can be slowed down. It is possible to prevent an engine stall that occurs when the engine suddenly moves toward the fully closed direction and blocks air.

Furthermore, since the mounting position of the elastic member 9 can be adjusted by moving the screw 11 relative to the side housing 1a, the elastic member 9
θ due to changes over time, etc. Even if a deviation occurs in the position, it can be corrected by manually adjusting the screw 11.

In addition, in the conventional link-type throttle valve opening/closing mechanism, the throttle valve is driven only by the accelerator pedal.
The amount of leakage air when the throttle valve is fully closed is strictly controlled in order to maintain the idle speed at a predetermined speed. Therefore, it was necessary to adjust the mechanically fully closed position using the screw 11.

On the other hand, according to the present invention, by driving the motor 4 even when the accelerator pedal 5 is not depressed, it is possible to electrically control the rotation speed to, for example, reach the idle speed, as described above. Eliminates the need for precise adjustments.

In the above configuration, when the driver operates the accelerator pedal 5, the opening signal from the accelerator sensor 6 is transmitted to the control device 7.
The control device 7 drives the motor 4 by outputting a predetermined number of pulses that determine the amount of rotation of the motor 4 . This motor 4 then rotates the throttle valve 2 and lever 8 provided on the throttle shaft 3. then,
Even if the amount of rotation of the throttle valve 2 is smaller than θ1 and the contact piece 8a of the lever 8 contacts the elastic member 9, the driving force of the motor 4 is large, so the throttle valve is rotated against the biasing force of the elastic member 9. The opening degree of 2 can be adjusted. Note that the throttle valve 2 rotates within a range of approximately 90' from fully closed to fully open. In addition, when the motor 4 stops, the lever 8 presses the elastic member 9 due to the force of the return spring 10, and the elastic member 9 and the return spring 10 are balanced at a position where the throttle valve 2 is slightly opened than the fully closed position. θ. It will be held in place.

By the way, in the above embodiment, the control device 7 functions as the control means of the present invention, the motor 4 functions as the drive means of the present invention, and the return spring 10 functions as the first biasing means, the contact piece 8a, the elastic member 9, and the screw 11. constitutes the second biasing means 4i of the present invention.

Note that a speed change means for changing the speed of motor rotation may be provided between the motor and the throttle shaft.

Further, the elastic member 9 may be formed of a metal spring, and may be attached to the lever 8 side instead of the intake pipe 1 side.

In addition, the means for biasing the throttle valve in the opening direction is not a rubber member fixed to the intake pipe, but a coil-shaped opener spring provided on the throttle shaft in the same way as the return spring. Both the return spring and the return spring may be provided on the throttle shaft so as to generate urging forces in opposite directions.

〔Effect of the invention〕

As described above, with the configuration of the present invention, when the drive means is activated, the throttle valve moves in the range from fully closed to fully open against the respective biasing forces of the first and second biasing means. Also, if the driving force from the driving means is cut off,
The throttle valve is moved to a position where the mechanical biasing forces of the first and second biasing means are balanced, and the throttle valve opens the passage in the intake pipe by a predetermined amount. Furthermore, since the position of the throttle valve is supported by the balance between the urging forces from the first and second urging means, the opening degree is difficult to change even if an external force is applied, and even if the position changes once the position is changed. However, it is immediately returned to its original position by the biasing forces from the first and second biasing means. Therefore, it is possible to compensate for the minimum amount of throttle valve opening required when restarting the engine, and the throttle valve opening required to move the vehicle in the event of a failure in the throttle valve drive system. It has a positive effect.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an engine throttle valve control device according to an embodiment of the present invention, FIG. 2 is a side view of the main parts of FIG. 1,
FIG. 3 is a graph showing the biasing forces of the elastic member 9 and return spring 10 in FIG. ■... Intake pipe, 2... Throttle valve, 4... Motor forming drive means, 7... Control device forming control means,
8a, 9.11...Contact piece 9 elastic member serving as second biasing means, screw, 10...Turn spring serving as first biasing means, 12...Intake passage.

Claims (5)

[Claims] (1) A control means that is provided in the intake pipe of the engine and that determines the opening degree of a throttle valve that adjusts the flow rate of combustion air in accordance with at least an amount of accelerator; a driving means for driving the valve between a fully closed position and a fully open position; a first urging means for mechanically urging the throttle valve in a closing direction; and a direction opposite to the first urging means. and a second urging means for mechanically urging the throttle valve, wherein the urging force of the first urging means is smaller than the driving force of the driving means in the throttle valve opening direction, and the driving means The urging force of the second urging means is set to be smaller than the driving force in the throttle valve closing direction, and the position where the urging forces of both the first urging means and the second urging means are balanced is set to A throttle valve control device for an engine, characterized in that the throttle valve is set at a position that opens a passage in an intake pipe by a predetermined amount. (2) The second biasing means includes: a movable stopper that moves together with the throttle valve; a fixed stopper provided in the intake pipe that restricts movement of the throttle valve in the closing direction; and the movable stopper and the fixed stopper. The engine according to claim 1, further comprising an elastic member provided on at least one of the stoppers and generating a biasing force by contracting when the movable stopper and the fixed stopper come into contact with each other. throttle valve control device. (3) The throttle valve control for an engine according to claim 1 or 2, wherein the driving means includes a motor, and the rotation axis of the motor and the throttle valve is coaxial. Device. (4) The engine throttle valve control device according to claim 3, wherein the first biasing means is a coiled spring wound around the rotating shaft of the throttle valve. (5) When the accelerator amount is 0, the control means causes the driving means to drive the throttle valve so as to achieve a predetermined idle rotation.
An engine throttle valve control device according to any one of items 1 to 4.