JPS58206853A - Working pressure transmitting device for actuator - Google Patents

Abstract

PURPOSE:To protect an actuator from positive pressure, by providing a one way valve preventing transmission of the positive pressure to an actuator by connecting pressure within a duct with the atmosphere only when the former is in the positive pressure in the midst of a pressure transmission duct between a pressure signal source and the actuator. CONSTITUTION:As a connecting hole 15 with the atmosphere is closed by a valve 14 of a one way valve 12 through negative pressure by generating negative pressure at a port 9 according to the opening of a throttle valve 8, in a normal operation range where a supercharger 3 does not actuate, the negative pressure is led into the negative pressure chamber 11 of an EGR valve 5 through a hose 10. When the led negative pressure overcomes resistance of a spring 13, a diaphragm 16 is raised, a duct 7 is opened by a valve 6 and part of exhaust gas is fed to a suction air pipe 4 through an exhaust pipe 2, a hose 20, the duct 7 and a hose 21. On the one hand, in an operation range where the supercharger 3 actuates, the suction air pipe 4 and the port 9 become positive pressure. In this instance, as the valve 14 is opened and the positive pressure is released through the connecting hole 15 with the atmosphere, transmission of the positive pressure to the negative pressure chamber 11 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for transmitting operating pressure to a diaphragm and an actuator, which is used in a supercharged internal combustion engine and uses negative pressure in an intake pipe as an operating source.

Conventionally, as the operating pressure source for the actuator, the (1) throttle valve of the carburetor, the boat provided in the F flow, or the Jl negative pressure (from the intake pipe) has been used. However, in a supercharged internal combustion engine, high positive pressure is generated in the supercharging region, and if this positive pressure is directly transmitted to the actuator, a problem arises in that the diaphragm pressure receiving portion is damaged.

Conventionally, the structure of the pressure receiving part has been changed (for example, to prevent the diaphragm from reversing), or an on-off valve that stops the transmission of positive pressure has been provided in the middle of the passage to the actuator.

The present invention has been devised in view of the above background, and includes cutting off communication with the atmosphere when the pressure in the passage between the pressure signal source and the actuator is negative, and transmitting the negative pressure to the actuator. By providing a one-way valve that communicates with the atmosphere when there is positive pressure and prevents transmission of positive pressure to the actuator, conventional actuators can be used as is, and a simple and inexpensive internal combustion engine with a supercharger can be used. The present invention provides an operating pressure transmission device for an engine actuator.

Hereinafter, the present invention will be explained based on examples.

(2) FIG. 1 shows the present invention applied to an exhaust gas recirculation device. 1 is an internal combustion engine; 3 is a supercharger; the turbine 17 receives exhaust gas pressure from the exhaust pipe 2 and rotates; another coaxial turbine 18 compresses intake air from an air cleaner (not shown) to supercharge the intake pipe 4. 4 Ru. Reference numeral 5 denotes an exhaust gas control well (hereinafter referred to as an EGR valve) which serves as an actuator, and a shaft 19 is fixed to a diaphragm 16, and a valve b is provided at the tip of the shaft 19. A spring 13 is provided in the negative pressure chamber 11 and urges the diaphragm 16 in the direction in which the valve 6 closes the passage 7. The negative pressure chamber 11 is connected to the hose 1
0 is connected to a boat 9 provided in the L stream of the throttle valve 8. Also, the hose IO branches in the middle and connects to valve 1.
4 is connected to a one-way valve 12 that opens and closes the popular communication hole 15.

In such a configuration, in a normal operating range where the supercharger 3 does not operate, negative pressure is generated in the boat 9 depending on the opening degree of the throttle valve 8. At this time, the valve 14- of the one-way valve 12 becomes negative pressure and closes the communication hole 15, so that the negative pressure is introduced into the negative pressure chamber 11 of the EGR valve 5(3) via the hose 10. Introduced negative pressure is spring 13
When the drag force is overcome, the diaphragm is pulled upward in the figure, valve 6 opens passage 7, and part of the exhaust gas flows into exhaust pipe 2.
, hose 20, passage 7, and hose 21 (supplied to the intake pipe 4. However, if no negative pressure is generated in the boat 9, or if the generated negative pressure is smaller than the drag force of the spring 13, the valve exhaust gas is not supplied because they close the passage 7. In this way, exhaust gas recirculation (hereinafter referred to as E
(denoted as Gk) is performed.

By the way, in the operating range where the supercharger 3 operates, the intake pipe 4 and the boat 9 are under positive pressure. At this time, the valve 14 of the directing valve 12 opens, and the positive pressure is released to the atmosphere through the popular communication hole 15. As a result, direct transmission of positive pressure to the negative pressure chamber 11 of the EGR valve 5 is prevented, and effects such as prevention of malfunctions due to inversion of the diaphragm 16 and no need to take measures to strengthen the diaphragm can be obtained.

FIG. 2 shows 12 embodiments according to the invention.

In this example, the boat 9 is provided with an orifice 22 (4). The orifice 22 may be located anywhere between the boat 9 and the branch point 23 of the one-way valve 12. In this example, by providing the orifice 22, it is possible to prevent the supercharging air from escaping wastefully through the popular communication hole 15 and reducing the supercharging pressure. Also, orifice 22
The subsequent positive pressure of the hose 10 can be brought closer to atmospheric pressure.

The third example is a third embodiment of the present invention. In this example, is applied to an EGR device using a known pressure regulating valve 23 that receives a signal from the constant pressure chamber 25 of the EGR valve 5 through the hose 2b and regulates the operating pressure to the negative pressure chamber 11. .

That is, in this embodiment, the pressure regulating valve 2 is used as the actuator.
3 applies, and even if the turbocharger 3 operates, the boost pressure will be lower than the pressure regulating valve 2.
This prevents the pressure from being transmitted to the pressure regulating chamber 25 of No. 3. therefore,
The effect is that the inversion of the diamond diaphragm 26 is prevented and that measures for strength of the diaphragm are not required.

Further, Fig. 1184 shows another embodiment of the one-way valve. A valve 28 is provided to close a valve seat 30 by a spring 29, and when the positive ratio of the hose 10 reaches a predetermined value (5), the valve 28 opens and releases positive pressure to the atmosphere.
゜A similar effect can be obtained by this.

Historically, the above-mentioned embodiments have been applied to EGR systems, but the present invention can be applied to pressure transmission systems for all actuators whose operating lines are the negative pressure of an intake pipe or a boat. Further, although an example is shown in which a turbocharger is used as a supercharger, the present invention can also be applied to an internal combustion engine with a supercharger using other means such as a supercharging method using an air bonozo.

As explained below, in the present invention, a 1/1 direction valve is provided in the passage leading the intake pipe pressure to the actuator, which releases the pressure in the passage to the atmosphere when the pressure in the passage exceeds atmospheric pressure. This has an excellent effect in that it is possible to prevent pressure from being applied directly to the tie gamma flamm surface of the actuator, and there is no need to take special measures to strengthen the diaphragm.

Moreover, in the present invention, the above effects can be achieved with a simple configuration such as simply providing a one-way valve, so the overall cost does not increase significantly.

[Brief explanation of the drawing]

(6) Figure 1 is a block diagram showing 11 embodiments of the device of the present invention, Figure 2
The figure is a block diagram showing the mounting part of the second embodiment of the device of the present invention, FIG. 3 is a block diagram showing the third embodiment of the device of the present invention, and FIG. FIG. 2 is a configuration diagram showing main parts of an embodiment. l...Engine, 3...Supercharger, 4...Intake pipe,
5. Actuator 4' E G R valve, 10.
··aisle. 12...One-way valve, 16...Diaphragm. Attorney Takashi Okabe (7)

Claims (1)

[Scope of Claims] An actuator comprising a pressure chamber and a diaphragm and displacing the diaphragm in response to pressure introduced into the pressure chamber; and a one-way valve disposed in the middle of the passage to release the pressure inside the passage to the atmosphere when the pressure inside the passage is higher than a predetermined pressure, and a supercharger that pressurizes the intake air in the intake pipe. operating pressure transmission device.