JPH0219656A - Idling speed controller for engine - Google Patents

Abstract

PURPOSE:To make differential pressure between two valve bodies balanceable by installing a vacuum connecting opening in a part approximating to a valve seat of the first valve body. CONSTITUTION:In an idling speed controller 20, a valve seat 34 for checking any movement in the closing direction of a valve body 30 in contact with a partition wall 22 is formed in this first valve body 30, but no valve seat is installed in a second valve body 32. Accordingly, a vacuum connecting opening 40 is installed in a part approximating to the valve seat 34 of the first valve body 30, and it is led into a solenoid device 22 by way of a vacuum passage 42 of a valve stem 28. With this constitution, force in the closing direction of these valve bodies 30, 32 is negatable by dint of engine suction pressure leading to the solenoid device 22 as far as a constant stroke position since these valve bodies 30, 32 have been fully closed. Accordingly, under all conditions, the idling speed controller 20 can control engine speed at the time of idling in an accurate manner.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is an engine idle speed control device, more specifically, a device for bypassing a throttle valve provided in an intake passage of an engine equipped with a fuel injection device. The present invention relates to an air valve device that is installed in a bypass passage and controls the rotational speed of an engine.

[Background of the Invention] In an engine equipped with an electronically controlled fuel injection device that controls the fuel 71 required by the engine by a computer instead of a carburetor, a throttle valve is provided in the intake passage of the engine. The air flow inside is controlled by this throttle valve. A throttle valve switch installed in the throttle valve chamber detects the open/closed position of the throttle valve and sends a single message to the computer.

When the engine is operated at a so-called idling time, when the engine is operated to such an extent that the engine does not stop, the amount of air taken into the engine is at its lowest, and the amount of fuel injection is at its lowest. In this case, the amount of intake air can be adjusted by providing a flow rate control means in the air passage that bypasses the throttle valve, thereby controlling the idle speed.

As a control means, for example, Japanese Patent Application Laid-Open No. 55-30546
In the method disclosed in Japanese Patent Publication No. 58-57623, two valve bodies having the same diameter are arranged on the same axis, and the differential pressure acting on the upstream and downstream surfaces of the two valve bodies is used to
Those configured to cancel out the forces acting on both valve bodies are widely used.

These #! If a valve seat is provided for each valve body, the valve body cannot be assembled due to its structure, so the valve body must be separated. It has also been proposed to omit the valve seat for one of the valve bodies to avoid the above-mentioned problems.

In particular, with a structure in which one valve seat is omitted, the balance between both valve bodies is lost when the valve is fully opened, and there are many disadvantages in setting the position of the valve body, etc., and there are also disadvantages economically. .

[Objective of the Invention 1] In consideration of the above-mentioned problems, the main object of the present invention is to control the idle speed of an engine by using an extremely simple engine control system that balances the differential pressure between two valve discs. The goal is to provide equipment.

[Configuration 1 of the Invention] A preferred embodiment of the engine idle speed control device according to the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, air supplied to the engine 10 is sent via an intake passage 12, and fuel is injected and supplied from a fuel injection valve device 14.

A throttle valve 16 for controlling the amount of air supplied is provided in the intake passage 12, and its opening degree is normally controlled in conjunction with the accelerator. A bypass passage 18 is provided bypassing the throttle valve 16, and an idle rotation speed control device 20 is provided at this location in order to control the flow rate of air passing through the bypass passage 18 during idle.

This idle speed control device 20 performs its gauging between the first partition wall 22 and the second partition l! i24, and is divided into a first chamber A and a second chamber B communicating with the upstream side of the bypass passage 18, and a central chamber C communicating with the downstream side. Both partitions 22.24 are provided with openings that cooperate with valve bodies 30.32, which will be described below. An actuator, ie, an electromagnetic device 26, which can be controlled by a computer output signal, is disposed at the end of the first chamber A of the control device 20, and a valve shaft 28 is provided so that the actuator can be moved in the longitudinal direction. . A first valve body 30 is fixed to the shaft 28 and is capable of opening the opening of the first partition wall 22 and guiding air from the upstream side of the bypass 18 to the central chamber C via the first chamber A. Also, a second valve body 32 is fixed, which can open the opening of the second partition wall 24 and guide air from the upstream side of the bypass 18 to the central chamber C via the second chamber B. Note that there is a gap in the first valve body 30! A valve seat 34 is formed to contact the valve body 22 and prevent movement of the valve body 30 in the closing direction. However, the second valve body 32 is not particularly provided with a corresponding valve seat. Furthermore, a first coil spring 3 is provided at the end of the valve shaft 28 on the electromagnetic device 26 side for pushing the valve bodies 30 and 32 in the closing direction.
6 or more are arranged.

The other end of the valve stem 28 extends in the longitudinal direction from the valve body 32, and is provided with a guide 38 and a second coil spring 39 that can push the valve bodies 30, 32 in the direction of opening. The air flowing from the bypass passage 18 through the idle speed control device 20 passes through the back side (lower surface) of the first valve body 30 when the valve body 30.32 is opened, and passes through the second valve body 3.
On the 2 side, it passes through the front surface (upper surface) of the first valve body 30.
Air from the side flows through the first partition wall 22 opened by the movement of the valve body 30, passes through the central chamber C between the valve bodies 30 and 32, and flows to the downstream side of the bypass passage 18. Further, air from the second valve body 32 side enters the central chamber C from the second chamber B through the opening of the second partition wall 24, and can flow to the downstream side of the bypass passage 18.

The configuration of the idle speed control device described above is the same as that commonly used in the past, but according to the present invention, a negative pressure communication opening is provided in a portion of the first valve body 30 near the valve seat 34. 40 is provided, and this opening 40 is connected to the valve stem 28.
The electromagnetic device 26 is led into the electromagnetic device 26 through a negative pressure passage 42 provided therein.

[Operations and Effects of the Invention] As described above, the present invention has been developed at its inception, so when air is flowing through the bypass passage 18, that is, the idle speed control device 20, The forces acting on the second valve body 32 cancel each other out and can be well controlled. By the way, the device 20 of this invention
Unlike the above, the first valve body 30 does not have a negative pressure communication phase opening [] 40, and the valve shaft 28 has a negative pressure passage 42 communicating with the electromagnetic device 22.
In a conventional device that does not have a first valve body 3
0 and the second valve body 32 are fully closed, the bypass passage 18
Since the intake negative pressure of the engine acts on the first valve body 30 of the device 20 from the downstream side of the engine, the first valve body 30 and the second valve body 3
The force balance between the valve body 30 and the valve body 2 is disrupted, and a force is generated that pushes the valve body 30° 32 in the closing direction. Therefore, when a linear solenoid or the like is used as the electromagnetic device 22, the valve body 30° 32 cannot be opened until the electromagnetic device generates a forceful thrust that acts in the direction of closing the valve body. On the contrary, the idle speed control device 20 of the present invention
According to the first valve body 30, a negative pressure communication opening 40 is provided, and the electromagnetic device 2 is connected to the electromagnetic device 2 through a negative pressure passage 42 of the valve shaft 28.
2, the force in the closing direction of the valve bodies 30, 32 can be canceled by the engine intake negative pressure reaching the electromagnetic device 22 from the time when the valve bodies 30, 32 are fully opened to a certain stroke position. can. Therefore, in all conditions, the idle speed control device 20 of the present invention can accurately perform idle control.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the relationship between the engine speed control device and the engine according to the present invention, and FIG. 2 is a schematic sectional view for explaining the present invention in detail. The main reference numbers in the first drawing are as follows. lO... Engine 12... Intake passage 16... Throttle valve 18... Bypass passage 20... Idle speed control device 26... Electromagnetic device 28... Valve shaft 34... Valve seat 40... Negative pressure communication opening 42... Negative pressure passage Figure 2 d Mohe d et al.

Claims (1)

[Claims] A control device is provided in a bypass passage that bypasses a throttle valve provided in an intake passage of an engine, and the control device is connected to a valve shaft operated by an electromagnetic device and a valve shaft of the same diameter fixed at a distance from the valve shaft. The first valve body is provided with a valve seat, and the back surface of the valve body and the front surface of the second valve body are connected to the upstream side of the bypass passage. In the device, the first valve body and the second valve body are separated by a partition wall so as to communicate with the downstream side of the bypass passage, and the electromagnetic device is actuated by a signal from a microcomputer. An engine idle speed control device, characterized in that a negative pressure communication opening is provided in a portion adjacent to the valve seat, and a negative pressure passage is provided in the valve shaft that communicates from the opening to the electromagnetic device. .