JPS6334306A - Actuator for engine intake control valve - Google Patents

Abstract

PURPOSE:To easily adjust the opening/closing characteristics of a control valve, by providing an adjusting valve having an adjusting spring and driven by a third diaphragm, among a positive pressure chamber, a negative pressure chamber and a pressure discharge chamber communicated with the atmosphere. CONSTITUTION:A first diaphragm 13 is formed with a third diaphragm 26 provided in a space defined between a spring seat 18 and a retainer 19. A valve member 27 is fixed at a central portion of the diaphragm 26, and is loosely inserted into a spacer 20. Thus, a small-diameter discharge passage 28 is adapted to be opened and closed by the valve member 27. An adjusting spring 29 is provided in a space defined between the spring seat 18 and the third diaphragm 26, thus constructing an adjusting valve 30. Accordingly, the adjusting spring 29 of the adjusting valve 30 discharging a positive pressure or a negative pressure operates to freely change the opening/closing characteristics of a control valve 9 and thereby provide a proper opening/closing characteristics according to an engine. Further, the effect of emission control and fuel consumption control may be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The actuator of the present invention is used in a drive device that opens and closes a control valve provided in an intake system equipped with a supercharger depending on the load condition of an engine.

In the intake system of an engine, a control valve is provided for each intake passage of the intake manifold9.For example, at high load, this control valve is opened to supply a large amount of air-fuel mixture to the °C engine, but at no load or low load, this control valve is opened. The technology for supplying a small amount of air-fuel mixture to the engine through a notch in the control valve or an auxiliary passage that bypasses the control valve when closed and creating a swirl to reduce exhaust gas and fuel consumption was disclosed in Japanese Patent Laid-Open No. 54-9.
9826 (known).

The control valve is driven by a diaphragm actuator operated by negative pressure in the intake pipe generated downstream of the throttle valve in the intake system. As shown in FIG. 6, this actuator is constructed by fixing a first diaphragm 41 with a large effective area and a second diaphragm 42 with a small effective area to an operating rod 43 with a constant distance between them. The space between the diaphragms 41 and 42 is opened to the atmosphere to form an atmospheric chamber 44, and the opposite side of the atmospheric chamber 440 across the first diaphragm 41 is formed as a negative pressure chamber 45 and communicates with the downstream side of the throttle valve of the intake system. It is constructed by inserting a diaphragm spring 46.

In this configuration, the first and second diamond slams 41.4
The effective area of 2 is AI, A2 is the spring force of the diaphragm spring 46, and the intake pipe negative pressure introduced into the negative pressure chamber 45 is Pl.
, the pressure in the atmospheric chamber 44 is P2, then the 9 operating rod 43 has a force F1 due to the pressure in the negative pressure chamber 45 of p'1=pl・A[-W, and a force F1 due to the pressure in the atmospheric chamber 44, F2= P2・
A force F2 of (At −A2) −W acts. That is, when the force acting on the first diaphragm 41 becomes Pl・Al>W, the operating rod 43 moves toward the negative pressure chamber 45 to close the control valve, and when +P1・Al<W, the operating rod 43 moves in the opposite direction. The negative pressure side characteristics are determined by the diaphragm spring 46. Further, the characteristics on the atmospheric side are determined by the effective area pressure difference between the two diaphragms 41 and 42.

By the way, when a supercharger is installed in the intake system in order to increase the engine's air-fuel mixture filling and improve output, the positive pressure generated by the supercharger is applied to the control element III of the control valve to ensure proper opening and closing. It is necessary to do so. however,
@K above the throttle valve in the atmospheric chamber 44 of the conventional actuator
I11! Introducing the positive pressure in the intake pipe of I, °1jilJ 'f
The force F2 that acts on the operating rod 43 when applied to the a11 element is determined by the difference in effective area between the two diaphragms 41 and 42, so when the characteristics of the negative pressure side are determined by the diaphragm spring 46, the positive pressure side In order to arbitrarily determine the characteristics of the control valve, it is necessary to change the diaphragms 41 and 42, and it is virtually impossible to adjust the opening and closing characteristics of the control valve to be appropriate depending on the engine.

The present invention makes it easy to control the opening and closing characteristics of a control valve installed in an intake system equipped with a supercharger. The present invention provides an actuator that can perform four adjustments.

The present invention is arranged at regular intervals.

two diaphragms with different effective areas to which the operating rod for driving the control valve is fixed; a positive pressure chamber formed between the two diaphragms and communicating with the upstream i11 of the throttle valve in the intake system; a negative pressure chamber formed on the opposite side of the positive pressure chamber across the diaphragm and communicating with the downstream side of the throttle valve of the intake system; and a diaphragm spring inserted into the negative pressure chamber and acting on the first diaphragm. and; a valve body driven by a third diaphragm operated by the differential pressure between the positive pressure chamber and the negative pressure chamber, and a discharge passage that is opened and closed by the valve body and communicates the positive pressure chamber or the negative pressure chamber with the atmosphere. and an adjustment valve having an adjustment spring that acts on the valve body in the valve closing direction, thereby providing means for solving the above problem.

action The operation will be explained according to the embodiment shown in FIG.

Assume that when the effective areas of the first and second diaphragms 13 and 14 and the spring force of the diaphragm spring 25 are set, the pressure in the negative pressure chamber 24 gives the p-pressure side characteristics as shown in Figure 4.5C. .

In the case of a conventional product in which the pressure in the positive pressure chamber 22 is not adjusted, the characteristics on the positive pressure side as shown in FIG. 4B are exceeded due to the difference in effective area between the two diaphragms 13 and 14.

When the positive pressure introduced into the positive pressure chamber 22 is high or when the negative pressure chamber 2
When the negative pressure introduced into 4 is high, the third diaphragm 2
6 compresses the adjustment spring 29 to move the valve body 27 in the valve opening direction, and releases the pressure in the positive pressure chamber 22 from the release path 28 to the atmosphere. on the other hand.

The first and second diaphragms 13 and 14 have a difference in their effective areas and a pressure difference between the positive pressure chamber 22 and the negative pressure chamber 24.

According to the spring force of the diaphragm spring 25, the actuating rod 11 is moved by acting together with the adjusting valve 30, and the regulating valve 30 is moved together with the actuating rod 11 in accordance with this movement. When the force acting on the third diaphragm 26 reaches the set value, the valve body 27 closes and the positive pressure chamber 2
2 pressure and 1st.

The operating rod 11 is moved according to the difference in effective area between the second diaphragms 13 and 14 and the spring force of the diaphragm spring 25.

That is, the characteristics on the positive pressure side can be arbitrarily determined by the adjustment spring 29, and the control valve can be opened and closed within a small pressure change range, and can be arbitrarily set within the range A shown by diagonal lines in FIG.

According to the present invention, the opening and closing characteristics of the control valve can be freely changed by adjusting the adjustment valve that releases positive pressure or negative pressure, and the opening and closing characteristics suitable for the engine can be achieved with a simple means, and the exhaust gas It would be possible to improve the effectiveness of measures against weight and fuel efficiency.

Example Embodiments of the present invention will be described based on the drawings.

Figure 1 shows an example of an intake system equipped with the actuator l of the present invention, in which an intake passage 4 is provided with a supercharging function 2 and a throttle valve 3, and each intake passage is provided with ft+lI? The intake manifold 5 provided with the Igl valve 9 constitutes an intake pipe 6, and the control valve 9
It has an auxiliary passage 7 that bypasses the engine and opens near the cylinder inlet of the engine/8. When the engine 8 is under no load or under low load, the control valve 9 closes and the air-fuel mixture is supplied to the engine 8 little by little from the auxiliary passage 7.

When the load is high, the control valve 9 opens and supplies the air-fuel mixture to the engine.

The control valve shaft lO is an operating rod 1 protruding from the actuator l.
1 and a link 12.

The first diaphragm 13 and the second diaphragm 14, which have different effective areas of the actuator l, are connected to the upper txlS cover 1.
5. Intermediate cover 16. They are arranged in rows with their respective peripheral edges fixed to the lower cover 17.

The center of the spring receiver 18 and retainer 19 fixed to both sides of the first diaphragm 130, which has a larger effective area, is away from the diaphragm 13, and the center between the retainer 19 and the second diaphragm 14, which has a smaller effective area. Both ends of a pipe-shaped spacer 20 are fixed to the section, so that the two diaphragms 13, 14 maintain a constant distance and move together. The operating rod 11 is fixed to the two diaphragms 13 and 14 by being fitted into a spacer 20.

A space surrounded by the two diaphragms 13 and 14 and the intermediate cover 16 forms a positive pressure chamber 22 that communicates with the upstream side of the soft valve 3 of the intake pipe 6 through a positive pressure passage 21, and 13 and the upper cover 15 forms a negative pressure chamber 24 that communicates with the valve downstream of the throttle valve 3 of the intake pipe 6 through a negative pressure passage 23, and a diaphragm spring acting on the first diaphragm 13 25 is inserted into the negative pressure chamber 24.

FIG. 2 is for adjusting the pressure in the positive pressure chamber 22, and the portion of the first diaphragm 13 where the spring receiver 18 and the retainer 19 are separated and facing each other constitutes a third diaphragm 26. A valve body 27 fixed to the center thereof is loosely inserted into the spacer 20, and the valve body 27 opens and closes a small diameter discharge passage 28 formed by opening the operating rod 11 from its base end face toward the side surface in the atmosphere. At the same time,
An adjusting spring 29 is inserted between the spring receiver 18 and the third diaphragm 26, and these constitute a regulating valve 30. The spring receiver 18 and the retainer 19 have a third diaphragm 26 and a negative pressure chamber 24. Communication holes 18m and 19m are provided, respectively, through which the pressure of the positive pressure chamber 22 is applied.

FIG. 3 is for adjusting the pressure in the negative pressure chamber 24, and a discharge passage 28 passes through the upper cover 15 from the spring receiver 18 through the negative pressure chamber 24, and is opened to the atmosphere through a throttle 28a.
The valve body 27 fixed to the center of the third diaphragm 26 is inserted into the inlet of the discharge passage 28 to form a regulating valve 30 to open and close the discharge passage 28.

The operation of the regulating valve 30 in these two embodiments and the accompanying movement of the operating rod 11 are as described above. Incidentally, the same is true when the 1itlj (fl valve 9 is opened at the time of high negative pressure or high positive pressure).

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an example of an intake system equipped with an actuator of the present invention, Fig. 2 is a longitudinal cross-sectional view showing an embodiment of the present invention, and Fig. 3 is a longitudinal cross-section fIjI showing a different embodiment of the present invention.
β diagram, Figure 4. FIG. 5 is a characteristic diagram of control valve opening/closing, and the sixth factor is a vertical cross-sectional view of a conventional example. l... Actuator, 11... Operating rod. 13.14...Diaphragm, 22...
・Positive pressure chamber, 24... Negative pressure chamber, 25...
Diaphragm spring, 26...Third diaphragm, 27...Valve body, 28...Discharge passage, 29...Adjustment spring, 30... ...A4 valve adjustment.

Claims (1)

[Scope of Claims] Two diaphragms (13, 14) having different effective areas, which are arranged at a constant interval and fixed to an operating rod (11) for driving a control valve; ) and communicated with the upstream side of the throttle valve of the intake system; and a positive pressure chamber (22) on the opposite side of the positive pressure chamber (22) with a first diaphragm (13) having a large effective area in between. a negative pressure chamber (24) formed and communicating with the downstream side of the throttle valve of the intake system; a diaphragm spring (25) inserted into the negative pressure chamber (22) and acting on the first diaphragm (13); ; a valve body (27) driven by a third diaphragm (26) operated by the differential pressure between the positive pressure chamber (22) and the negative pressure chamber (24); a discharge passageway (28) that opens and closes with the opening and closing the positive pressure chamber (22) or the negative pressure chamber (24) to the atmosphere; and an adjustment spring (29) that acts on the valve body (27) in the valve closing direction. An actuator for an engine intake control valve, comprising: a regulating valve (30);