JPH01100332A - Feed air flow control device - Google Patents

Abstract

PURPOSE:To improve the control precision by arranging an air flow control section constituted of a thermo-sensitive valve and the electrically controlled second air flow control section face to face and mutually interlocking them in an air flow control valve opening or closing a bypass passage detouring a throttle valve in response to the operation state. CONSTITUTION:In an air flow control valve provided on a bypass passage detouring the throttle valve of an intake passage, a solenoid 1 is arranged on one end of a casing provided with an outflow port 2 and an inflow port 3 of air, a plunger 17 is made movable to the left against a spring body 13 by its excitation. A diaphragm 6 is connected to a hollow shaft body 19 brought into contact with the smooth surface 22 of this plunger 18 to form a pressure adjusting chamber 18, and the first valve body 9 is arranged on this shaft body 19. The other end of the shaft body 19 is slidably inserted into the hollow section 11 of the second valve body 10 facing the first valve body 9, and this second valve body 10 is supported by a thermo-sensitive section 12 arranged with a movable section 15 responding to the temperature of the cooling water via a spring body 14.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an air flow control valve that controls the amount of intake air in a fuel injection engine. It relates to something that has the function of opening and closing depending on the state.

[Conventional technology]

Conventionally, in a fuel-injected engine, a bypass passage that bypasses a throttle valve in an intake passage is provided with the
0584, which is equipped with a temperature-sensitive valve that responds to the engine cooling water temperature;
As shown in No. 8009, an air flow control valve is known which is provided with a solenoid valve that opens and closes depending on the operating state of the engine.

In the case of time opening 59-134360, the characteristics of the air flow rate with respect to the cooling water temperature fluctuate greatly, and the productivity is low in terms of accuracy.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technologies, the former depends only on temperature and has poor responsiveness, making it impossible to perform fine control according to the operating state of the engine, while the latter does not allow for control with relatively good responsiveness. In the third example, there are problems such as problems such as running out of control or stopping all functions due to electrical troubles, etc., and in the third example, productivity is hindered.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome these two drawbacks and to provide an air flow control device valve that is simple, inexpensive, productive, small, and compact.

[Means for solving problems]

' The above purpose is to arrange a first air flow control section consisting of a conventional temperature-sensitive valve and a second air flow control section that is electrically responsive by disposing a solenoid valve etc. to face each other. ,
The valve body of the second air flow control unit and the valve body of the first air flow rate control unit are opposed to each other and in contact with each other, and the second flow path is controlled by opening and closing the second valve body and the valve seat. An on-off valve section was formed, and an on-off valve section for the first flow path was formed by opening and closing the first valve body and the second valve body.

[Effect]

The first flow control section has poor responsiveness depending on the cooling temperature, but
It operates reliably and is difficult to be affected by sudden changes in flow rate due to electrical troubles.On the other hand, the second flow control section compensates for the poor response of the first, and the valve body is placed opposite the second flow control section. By configuring them in contact with each other, a compact and simple configuration can be obtained.

In addition, desired characteristics can be obtained by independently forming the flow paths of the second valve section that opens and closes in response to the cooling temperature and the first valve section that opens and closes using a solenoid valve. .

〔Example〕

An embodiment of the invention is shown in FIG.

1 is a solenoid, 2 is an air outlet, 3 is an inlet, 4 is a partition having a valve seat 5, and the left end is a diaphragm 6 with a lid 7 forming a pressure adjustment chamber 23, which is connected to a housing 8. Yoke on solenoid 1, smooth surface 22 on one end
The plunger 17 and the spring body 13 are arranged. A shaft body 19 having a hollow portion 11 that contacts the smooth surface 22 of the plunger 17 at one end is connected to the diaphragm 6, and a first valve body 9 is disposed therein. The other end of the shaft body 19 faces the first valve body and has a hollow portion 11 formed by the second valve body 10.
It is slidably arranged in electrical conduction with the The second valve body 10 has a guide part supported by a spring body 14 and a spring body interposed between the guide part and the temperature sensing part 12 which is provided with a movable part 15 that is displaced in response to the temperature of the cooling water. The second valve body is elastically supported.

The second valve body is configured to be movable in a predetermined area by engaging with the guide part, and the wax in the temperature sensing part 12 expands to cause the movable part 1 to move.
5 is displaced and comes into contact with the valve seat 5a. The flow from the inlet 3 is thus closed by the second valve body. Next, the second valve body 10 is formed with an annular protrusion 56 that comes into contact with the first valve body 9 and is connected to the outlet 2 by the flow path 21.
Connect with.

The inflow amount can be controlled by opening and closing the first valve body 9 independently of opening and closing the second valve body 10.

In the above configuration, when the solenoid 1 is excited and attracts the plunger 17, a gap is created between the shaft body 19 and the smooth surface 22, and the negative pressure at the outlet 2 on the negative pressure side is applied to the shaft body 19 in the pressure adjustment chamber 18. aspirate.

As a result, the shaft body 19 is displaced and separated from the second valve seat 5b at the tip of the annular protrusion 5b, forming an auxiliary flow path through which air flows to the outlet 2 via the flow path 21. On the other hand, when the second valve element is at a low temperature corresponding to the cooling water temperature of the temperature sensing part 12, the wax contracts in the temperature sensing part 12, and the valve seat 5a
It is separated from the main flow path 20 and forms a main flow path 20. On the other hand, when the cooling water temperature rises, the wax in the temperature sensing part 12 expands and presses the second valve element 10 through the guide part 16, causing the second valve element to come into contact with the valve seat 5a. As a result, the flow path 20 is cut off and closed. This is shown in Figure 2 as a relationship between cooling water temperature and flow rate. In Figure 2, the flow rate change A that changes due to the second valve body that changes according to the cooling water temperature, and the flow rate change B caused by the solenoid 1 that independently responds to the operating state are superimposed, resulting in the total flow rate. The configuration is controlled by

In the conventional example, the first flow path is formed by the first valve body 9 and the second valve body 10, and the second valve body 10 and the valve seat 4 are connected to each other.
Unlike the one according to the present invention, the second flow path formed by The displacement amounts of the valve bodies 9 correspond in a 1:1 ratio, and the flow rate is controlled by the size of the gap between them, so the dimensional accuracy 1 position accuracy affects the flow rate.

On the other hand, according to the present invention, two independent channels can be formed as described above. A constant flow rate can be obtained by simply opening and closing the valve body 9 without much influence on accuracy.For the second flow path, the second valve body 10 is positioned to determine the degree of opening based on the pal sheet 4. can.

In FIG. 2, the displacement of the second valve body 10 generally corresponds to the curves A and A' with respect to the cooling water temperature t, and the characteristics due to the displacement of the first valve body 9 responding to the solenoid 1 correspond to the curves. Corresponding to this, according to the present invention, there is little variation in the air flow rate Q with respect to the cooling water temperature of the songs PAA' and B.

〔Effect of the invention〕

Therefore, according to the present invention, there is provided a flow rate control function that prevents an engine stall when the engine is cooled by controlling the amount of intake air according to the engine cooling water temperature (engine temperature);
By controlling the intake air flow rate according to the engine operating state, it is possible to provide a function of improving the rotational speed accuracy during idling without icing, and also to obtain a flow control device that is simple in structure, inexpensive, and compact.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a flow rate control device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the relationship between cooling water temperature and air flow rate according to this embodiment. DESCRIPTION OF SYMBOLS 1... Solenoid, 2... Outlet, 3... Inlet, 4... Partition, 5a... First valve seat, 5b
...Second valve seat, 6...Diaphragm, 7
... Lid body, 8... Housing, 9... First valve body, 10... Second valve body, 11... Hollow part, 12...
- Temperature sensing part, 13... Spring body, 14... Spring plate, 15
...Movable part, 16...Guiding part, 17...Plunger, 18...Pressure adjustment chamber, 19...Shaft body, 20...
... Channel, 21... Channel, 22... Smooth surface. 10th 2nd Saki Yu degree - Natsume amount τ tolerance t

Claims (1)

[Claims] 1. A second flow path, which is located in the air passage bypassing the intake pipe and has a temperature-sensing section that senses the engine cooling water temperature, and forms a second flow path that opens and closes according to the engine cooling water temperature. Supply air characterized by being equipped with a temperature-sensitive valve having two valve bodies, and a drive unit that opens and closes the first valve body that comes into contact with and separates from the second valve body to form a first flow path. Volume control device. 2. A supply air amount control device according to claim 1, characterized in that the first valve body and the second valve body are configured to face each other in series. 3. The supply air amount control device according to claim 1, characterized in that the drive section for opening and closing the first valve body is constituted by a solenoid valve. 4. The supply according to claim 1, characterized in that the first flow path formed in the second valve body is formed only within a plane that intersects with the axis in the moving direction of the second valve body. Air volume control device.