JPH03290056A - Fluid control valve, holding member for fluid control valve and idle air quantity controller for automobile using fluid control valve - Google Patents

Abstract

PURPOSE:To stabilize the flow rate control characteristic by installing a shaft pressing means which applies the pressing force in the direction perpendicular to the shaft fixed on the valve body of an opening/closing valve so as to advance and retreat the valve in the axial direction and presses the shaft on the inner wall surface of a bearing by a prescribed force. CONSTITUTION:As for an air quantity control valve used for an idle revolution controller, a valve body 121 is separated from the edge part of a center shaft 105, when a solenoid assembly body 116 is conducted with electricity and a plunger 114 shifts to a core 115 side, and the negative pressure in a passage 102 passes through a hole 122, and then passes through the inside of the center shaft 105 and an orifice 132, and introduced into a chamber 123, and a valve 104 is opened through a diaphragm 110 by the pressure difference between a passage 103. In this case, a cup shape is formed from a thin metal plate, and a hole for the insertion of the center shaft 105 is formed at the center of a disc plate part 16, and a vibration suppressing member 13 which is formed by fixing a leaf spring 14 on the disc plate part 16 is fixed on the inner periphery of a valve case 101, and as prescribed pressing force is applied on the outer surface of the center shaft 105.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an on-off valve that controls the flow rate of liquid, and in particular, a valve that controls fluid by moving a valve body fixed to a shaft back and forth along the shaft. Related to fluid control valves.

[Conventional technology]

Fluid control valve known from Japanese Patent Application Laid-Open No. 56-94079,
Automobile fuel injection valves known from U.S. Pat. The rod-shaped valve shaft is moved back and forth in the axial direction by a driving force source such as an electromagnetic solenoid, thereby opening and closing the valve to control the flow rate of fluid.

[Problem to be solved by the invention]

The above conventional technology does not take into consideration the fact that the minute gap existing in the bearing part of the valve stem causes vibration and tilting of the valve stem in the direction perpendicular to the axis, and the flow rate characteristics of the fluid are not reproducible or the valve stem is When worn, the abrasion powder gets stuck in the gap between the valve stem and the bearing, causing stock of the valve stem, or the abrasion powder adheres to and accumulates on the valve seat and valve body surface, causing the valve port to close completely. There was a fear that it would cause the phenomenon of disappearance.

An object of the present invention is to prevent the vibration and tilting of the rod-shaped valve shaft, thereby eliminating the problems of the prior art described above.

The fluid control valve disclosed in Japanese Patent Application Laid-Open No. 56-96079 is configured to move forward and backward in the axial direction with the valve shaft supported by a leaf spring, but the valve shaft is fixed to the leaf spring. Therefore, when the valve stem moves back and forth, the locus of the fixed part of the leaf spring and the valve stem traces an arc, and for this reason, the valve stem cannot move straight along the axis.

As a result, the axis of the valve deviates from the center of the valve, making the flow rate control characteristics unstable.

[Means to solve the problem]

In order to achieve the above object, the present invention provides means for absorbing vibrations of the valve shaft in the direction perpendicular to the axis.

Specifically, means is provided for applying a pressing force to lightly press the valve stem against the inner wall surface of the bearing.

Alternatively, the valve stem and the valve may be sandwiched between a plurality of elastic plates attached to the inside of the valve case.

Note that these pressing forces and the force for pinching must be limited to a force that does not prevent the valve stem from moving back and forth in the axial direction.

A valve stem holding member used in such a fluid control valve consists of a disk having a hole in the center through which the valve stem is inserted, an annular body formed around the disk, and one end fixed to the disk or annular layer. and an elastic piece whose other end extends to near the center of the hole, the annular body portion is fixed to the circumferential surface of the valve case, and the tip of the elastic piece is pressed against the valve shaft passing through the hole. It looks like this.

Further, there may be a plurality of elastic pieces, and in this case, the valve stem is sandwiched between the elastic pieces.

[Effect]

The fluid control valve configured in this manner moves forward and backward with the valve shaft being lightly pressed against the inner wall surface of the bearing, so that the valve shaft does not vibrate in the direction perpendicular to the shaft.

In addition, since the valve stem is held by an elastic piece in the direction perpendicular to the axis, when the valve stem tries to displace in the direction perpendicular to the axis, the elastic piece absorbs this, so the valve stem is difficult to displace in the direction perpendicular to the axis. No vibration or tilting occurs.

In this way, a fluid control valve with stable flow control characteristics free from the above-mentioned problems can be obtained.

When used in automobile fuel injection valves, stable fuel metering becomes possible, the dynamic range is widened, and controllability when a small amount of fuel is supplied is improved.

Furthermore, if this is used in the idle air amount control valve of an automobile, the amount of bypass air when the engine is idling can be accurately controlled, eliminating engine stall due to insufficient air amount and abnormal speed increase due to excessive air amount.

This type of control valve used for fluid control in automobiles is particularly susceptible to the effects of engine vibration, but by using the control valve of the present invention, deterioration in flow characteristics caused by engine vibration can be eliminated.

The holding member is composed of a disk, an annular body, and an elastic piece fixed to these, and has a simple structure, and can be assembled by simply fitting the annular layer to the wall of the valve casing when assembling the control valve, making assembly easy. Good sex.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on an example in which the present invention is implemented in an idle air amount control valve for an automobile.

FIG. 4 shows an example of application of the present invention, where l is the intake pipe 2.
．． This is an engine equipped with an exhaust pipe 3.

The intake pipe 2 has a throttle valve 4. A throttle chamber 6 with a bypass passage 5 is provided. Furthermore, on the upstream side, there is an air flow meter 9 consisting of a vane 7 that measures the amount of air and a potentiometer 8 that converts the rotation angle of the vane 7 into an electrical output.
An air cleaner 10 is installed further upstream. Reference numeral 11 denotes an EGR valve that is left in the middle of a passage connecting the intake pipe 2 and the exhaust pipe 3, and is used to recirculate a part of the exhaust gas to the intake system.

12 is a water temperature sensor that detects the temperature of the cooling water of the engine 1 and converts it into an electrical output; 13 is a crank angle sensor that detects the rotation speed of the engine 1 and converts it into an electrical output; 14 receives various input signals; This is an arithmetic processing circuit (computer) that processes this and supplies predetermined outputs to the idle rotation control device 15 and fuel injection valve 16, and is in charge of the central part of the electronic control of the engine. The input is supplied by

The idle rotation control device 115 is installed in the bypass passage 5 of the throttle valve chamber 6 and controls the amount of bypass air that bypasses the throttle valve 4.

EMBODIMENT OF THE INVENTION Hereinafter, a first embodiment of an air amount control valve used in an idle rotation control device to which the present invention is applied will be described with reference to FIG.

A passage 102 of the valve case 101 passes on the downstream side of the throttle valve, and a passage 103 passes on the upstream side of the throttle valve. valve 10
A central axis 105 formed at the center of the valve case 10
It is held movable in the axial direction by a bearing 106 fixed to 1. The valve 104 can completely close the gap between the passage 102 and the passage 103 by coming into contact with a seat 107 fixed to the valve case 101. A crimping member 105a is fixed to the central shaft 105, and the plate 108 and the plate 109 are crimped and fixed by this member 105a, and the inner ring portion of the diaphragm 110 is sandwiched between the plate 108 and the plate 109. ing. Passage 103 is provided in plate 108 and plate 109.
An orifice 111 leading to is provided. An outer ring portion of the diaphragm 110 is sandwiched between a valve case 101 and a solenoid case 112. The bearing plate 129 is fixed to the cover 112 and has a central cylindrical portion that receives the shaft 105 inserted therethrough. Solenoid case 112
A solenoid assembly 116 is housed and fixed. The solenoid assembly 116 includes a plunger 114 movable in the same direction as the central axis 105, a core 115 that attracts the plunger 114, an annular coil 116a formed to surround the core 115 and the plunger 114, and the plunger 11.
4, a spring 118 that pushes the plunger 114 toward the valve 104, and an adjustment screw 119 that adjusts the set load of the spring 118 and supports the shaft 117 in its center bearing hole.
These are entirely molded with mold resin material 120. A rubber valve body 121 is fixed to the plunger 114. Furthermore, the bearing plate 129 and the plunger 1
A spring 113 is provided between the adjustment screws 14 and 14 to push the plunger 114 toward the adjustment screw 19.

In this configuration, the solenoid is a near solenoid, and its displacement with respect to current is linear. As the current increases, the plunger 114 moves toward the core 115 and the valve body 121 also moves together with the plunger 114, so that the valve body 121 separates from the end of the central shaft 105. The negative pressure in the passage 102 then passes through the hole 122 and passes through the passage 131. in the central shaft 105. It passes through the orifice 132 at the tip and is introduced into the chamber 123 between the diaphragm 110 and the solenoid case 112. Although some negative pressure is released through the orifice 111, the pressure inside the chamber 123 is lower than the pressure inside the passage 103 due to the large amount of negative pressure introduced, and the pressure difference between the pressure and the passage 103 causes the diaphragm 110 to move to the left in the drawing. to open the valve 104 via the shaft 105. Negative pressure leaking from orifice 111 and valve 121
Due to the balance of the negative pressure introduced from the plunger 114, the orifice 132 at the tip of the central shaft 105 moves to come into close contact with the valve body 121 of the plunger 114. When orifice 132 is closed, the pressure through orifice 111 attempts to equilibrate.

Accordingly, the diaphragm 110 is displaced to the right in the drawing, the orifice 132 is opened, and the negative pressure in the passage 102 is again transferred to the chamber 12.
3, and the diaphragm 110 moves to the left in the drawing. Thus, the valve 104 moves following the position of the plunger 114 and is held at that position.

The springs 113, 118, and 130 cause the valve 10 to
4. This has the effect of preventing the valve body 121 (that is, the plunger 114) from moving, and the adjustment screw 119 provided at the rear end of the solenoid has the effect of adjusting load variations during production and assembly of the spring 118.

In this device, the valve is fully open when there is no electricity, and even if the diaphragm 110 is torn, the valve remains closed, and even if the orifice 111 is clogged, the valve will not open as long as the valve 121 is closed. .

In this way, when each part fails, the valve 104 remains closed.

What is important here is that the central shaft 106 is supported by the bearing 106 and the bearing plate 129, and is biased in the axial direction by the above-mentioned springs 113, 118 or 130. Directional vibration cannot be suppressed.

Therefore, in this embodiment, a vibration suppressing member shown in FIG. 2 is provided on the inner periphery of the valve case 112. The vibration suppressing member 13 is made of a thin metal plate and has a cup shape, and has a hole in the center of the disk portion 16 through which the central shaft 105 is inserted. Further, a leaf spring 14 is fixed to the disc portion 16 with a rivet 17.

This leaf spring 14 is configured so that when the center shaft 105 is inserted into the hole, it contacts the outer surface of the center shaft 105 with a predetermined pressing force.

The cup-shaped vibration suppressing member 13 configured in this manner is fixed therein by fitting the annular portion 15 on its outer periphery to the inner annular portion of the valve case 01.

Next, the assembly of the control valve will be explained.

The solenoid assembly 116 is housed inside the solenoid case 112 with a seal ring 131 sandwiched between them.
The tip of the solenoid assembly 116 is crimped and fixed to the molded resin surface of the solenoid assembly 116.

A rubber valve body 121 is molded on the tip of the shaft 117, and is press-fitted into the center hole of the plunger 114 to fix both.

A spring 1 is attached around the shaft 117 of this plunger assembly.
18, and while inserting the shaft 117 into the bearing hole of the adjustment screw 119, the plunger 114 is loosely fitted into the center hole of the solenoid 116a.

Next, the spring 113 is set in the center hole of the plunger 114, and a bearing plate 129 is fixed to the end face of the solenoid 116a to receive one end of the spring. Plunger 114
At this time, is located where the pressing forces of springs 113 and 118 are balanced.

On the other hand, a caulking metal 105a is fixed to the central shaft 105, and a plate 108. The diaphragm 110 and the plate 109 are set in the metal fittings in this order from the left side in FIG. 1, the left end of the metal fittings is bent outward, and the three parts are crimped and fixed. Next, the vibration suppressing member is inserted into the central shaft, and then the valve 104 is molded and fixed at a predetermined position on the central shaft. The thus obtained central shaft assembly is constructed by inserting the outer cylindrical portion of the vibration suppressing member 13 into the valve case 101 with the valve 104 side end inserted into the hole of the bearing 106 around which the spring 130 is arranged. Press fit into the circumferential surface and secure.

While holding the outer peripheral edge of the diaphragm 110 on the flat part formed on the peripheral end surface of the opening of the valve case 101, insert the diaphragm side end of the central shaft 105 into the center hole of the plunger through the bearing hole of the bearing plate 129, and insert the end of the central shaft 105 into the center hole of the plunger. While touching the end face of the valve body 121, press the solenoid case 112.
The peripheral end surface on the opening side of the valve case 101 is overlapped with the peripheral edge of the diaphragm 110, and in this state, the peripheral edge of the end of the valve case 101 is bent inward and crimped onto the peripheral edge of the end of the solenoid case 112, thereby sandwiching the diaphragm 110. Fix both at this part.

In this state, the spring 118 presses the center shaft to the right in the drawing with a predetermined force against the forces of the springs 113 and 130, and thereby the valve 104 is pressed against the seat 107 with a predetermined pressure.

Furthermore, the leaf spring 14 applies a pressing force in the direction perpendicular to the axis, so-called side force, to the central axis 105, and as a result, the central axis 1
05, the cylindrical portion forming the bearing of the bearing plate 129, and the inner peripheral surface of the bearing hole of the bearing 106 with a predetermined side force. In this way, the center $1105 is not affected by the vibrations transmitted from the engine as an independent mass body, but is affected by the vibrations as a part of the valve assembly or solenoid assembly, so it is not affected by the vibrations transmitted from the engine. The body no longer vibrates.

By the way, when this side force acts, the spring 11
If the force of the spring 8 or the spring 130 is weak, the center shaft assembly cannot be moved in the axial direction, so it is necessary to use a correspondingly strong spring. The force of the spring is determined by the size of the side force. However, if the force of the spring 118 is increased, it becomes necessary to increase the electromagnetic force that attracts the plunger 114, so the force of the spring should be set in consideration of this electromagnetic attraction force.

Note that 120 in FIG. 1 is a connection terminal molded with resin, which is connected to an external power supply terminal and supplies power to the solenoid 116a.

122 is a blind plug that closes the outside of the adjustment screw 119 after it is set.

123 is a layer formed on the inner peripheral surface of the bobbin around which the winding of the solenoid 116 is wound, the surface exhibiting a low coefficient of friction, and is made of a non-magnetic material, a thin metal tube, a resin tube, or a coating of solid lubricant such as molybdenum disulfide. It is formed of layers, etc.
It has a function of smoothing the movement of the plunger 114 in the axial direction.

Alternatives for the vibration suppressing member 13 will be described below.

In FIG. 2, the member forming the leaf spring 14 is fixed to the disk portion 16 with a rivet 17, but the member may be fixed by spot welding instead of the rivet 17.

The one shown in FIG. 3 is constructed with a linear spring. This spring 14a consists of a curved part that is caught on the central shaft 105 and a coiled spring part that is held by an elastic force on the bottom peripheral edge of the cup-shaped member. , which is held on the inner peripheral edge of the cup-shaped member by the spreading force when released.

In the example shown in FIG. 5, a member having two symmetrically formed leaf springs is sandwiched between cut and raised pieces formed on a disc portion 16, and fixed by crimping the cut and raised pieces 16a. .

FIG. 6 shows a vibration suppressing member having two leaf spring pieces 14c and 14d assembled to the valve case 101.

In this case, the central axis 105 is the double leaf spring piece 14c.

14d, the central shaft is not pressed against the bearing 106 or the bearing plate.
Axial movement becomes smoother.

Next, improvements to the shape of the tip of the central shaft 105 and the orifice 132 formed therein will be explained based on FIGS. 7 and 8.

In this embodiment, the tip of the central shaft 105 is formed into a conical shape,
The contact portion with the valve body 121 is configured to be a line contact rather than a surface contact.

Specifically, the inclination angle θ of the conical surface of the orifice with a diameter of 1.2 mnt
was set at 7° so that the contact between the valve body 121 and the orifice portion was substantially circular.

Comparing this and the case of conventional surface contact in terms of adsorption force, as shown in FIG.
Whereas the adsorption force increased by about 0% (approximately 3 g), in the case of this example, the adsorption force did not increase and its decrease was faster.

Conventionally, the suction force was too large, and the diaphragm 110 had to be displaced greatly to separate them, and as a result, the distance between the valve body 121 and the tip of the central shaft 105 became too large after they were separated, and the valve 104 Its molecules were displaced as necessary and the control characteristics of air flow rate were causing an overshoot phenomenon.

In this embodiment, since the attraction force between the two can be made very small, this overshoot phenomenon can be eliminated.

As a result, even when a side force is applied to the central axis, the axial movement of the central axis does not become unstable, and a technology for applying side force can be realized.

〔Effect of the invention〕

According to the present invention, vibration of the center shaft in the radial direction is suppressed, and unstable movement of the valve can be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a control valve according to an embodiment of the present invention, and FIG.
The figures are a perspective view of the vibration suppressing member shown in FIG. 1, FIG. 3 is a perspective view of another embodiment of the vibration suppressing member, FIG. 4 is a system diagram showing an example of application of the control valve according to the present invention, and FIG. 6 is a perspective view showing still another embodiment of the vibration suppressing member, FIG. 6 is a sectional view of the main part of a control valve using the vibration controlling member of FIG. 5, and FIG. 7 is an improved structure of the orifice portion of the control valve. The partially enlarged sectional view shown in FIG. 8 is an explanatory diagram of the effect of the improved orifice structure of FIG. 7. 13... Vibration suppressing member, 14... Leaf spring, 101...
Valve case, 104... Valve, 105... Central shaft, 107... Valve chute, 110... Diaphragm, 112... Solenoid case, 114...
Plunger, Fig. 2 Fig. 5 Fig. 6a Fig. Fig. 5TROKEδ (mm)

Claims (1)

[Scope of Claims] 1. An on-off valve disposed in the middle of a fluid flow path, a shaft fixed to the valve body to move the on-off valve forward and backward in the axial direction, a driving force source that provides propulsive force to this shaft; A fluid characterized by comprising: a bearing means for supporting the shaft so as to move forward and backward, and a shaft pressing means for applying a pressing force to the shaft in a direction perpendicular to the shaft to press the shaft against the inner wall surface of the bearing with a predetermined force. control valve. 2. The fluid control according to claim 1, wherein the driving force source comprises a magnetic attraction force generating device using an electromagnetic solenoid, and the shaft includes a member attracted by the magnetic attraction force. valve. 3. A control valve disposed in a bypass passage that communicates the upstream and downstream of an intake throttle valve provided in an intake passage of an internal combustion engine, in which a rod-shaped valve stem with a valve body attached is moved in the axial direction of the valve stem. An idler for an internal combustion engine, in which the valve body is movably supported on a solenoid, and the passage area of the bypass passage is changed by displacing the valve body in the axial direction according to the amount of energization to the solenoid, thereby controlling the amount of air passing through the bypass passage. An automobile having a rotation speed control valve, characterized in that it is provided with a pressing means for urging a shaft on which the valve body is attached in a direction perpendicular to the axis within a range that does not interfere with the displacement of the valve body. Idle air amount control device. 4. A valve port provided between the inlet and the outlet of the fluid flow path, a valve body provided opposite the valve port, a shaft for operating the valve body, and both ends of this shaft supported so as to be movable in the axial direction. an electromagnetic device for applying an axial force to the plunger; a coil spring for urging the valve body in a direction to close the valve port; A fluid control valve comprising a spring means other than a spring. 5. A plunger and a hollow shaft that are provided in an air passage that bypasses the intake pipe and whose position is determined according to a signal input to a solenoid, a valve and a diaphragm mechanism that are provided on the shaft, and one end of the shaft is the valve. In an idle rotation control device, the idle rotation control device opens on the downstream side of the plunger, the other end opens into a negative pressure chamber partitioned by the diaphragm, and forms a valve mechanism with a seat provided on the plunger,
An idle air amount control device for an automobile, comprising a spring mechanism that applies a force to the shaft in a radial direction. 6. The idle air amount control device for an automobile according to claim 5, wherein the spring mechanism includes two or more springs that generate opposing radial forces around the shaft. 7. The idle air amount control device for an automobile according to claim 5, wherein the spring mechanism is a leaf spring. 8. The idle air amount control device for an automobile according to claim 5, wherein a wire is used for the spring mechanism. 9. The idle air amount control device for an automobile according to claim 7, wherein the holding means for the spring mechanism is spot welded. 10. The idle air amount control device for an automobile according to claim 7, wherein the holding means of the spring mechanism is formed by plastic bending of the holding member. 11. A disc having a hole in the center for inserting the valve stem, an annular mounting member formed around the disc and for attaching the disc to the valve housing, and a circular mounting member for the disc or the annular mounting member. A holding member for a fluid control valve, characterized in that it is an elastic piece that is held, extends toward the center of the hole, and applies a pressing force in a direction perpendicular to the axis to the valve shaft passing through the hole. 12. A fluid control valve characterized by being provided with vibration prevention means for preventing vibration of the valve stem. 13. In claim 1, the vibration prevention means is composed of at least two elastic bodies fixed to the inner wall of the valve case, and the valve shaft is slidably sandwiched between the curved ends of the elastic plates. A fluid control valve featuring: