JP2620571B2 - Car idle speed control valve - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-off valve for controlling the flow rate of a liquid, and more particularly, to controlling a fluid by moving a valve body fixed to a shaft along a shaft. The present invention relates to a fluid control valve.

[Conventional technology]

Japanese Patent Application Laid-Open No. 56-94079, a fluid control valve, a vehicle fuel injection valve disclosed in U.S. Pat. No. 4,360,161, etc., and a vehicle idle air flow disclosed in Japanese Patent Application Laid-Open No. 64-24133. The control valve and the like are configured such that the rod-shaped valve shaft on which the valve element is mounted is advanced and retracted 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. Have been.

[Problems to be solved by the invention]

The above prior art does not take into account that the minute gap existing in the bearing portion of the valve shaft causes vibration and tilting in the direction perpendicular to the axis of the valve shaft, and the flow rate characteristics of the fluid are not reproducible. The abrasion causes the abrasion powder to be trapped in the gap between the valve shaft and the bearing, resulting in the stocking of the valve shaft. This abrasion powder adheres and accumulates on the valve seat and the valve body surface, and the valve port is completely closed. Or cause a phenomenon that would not be possible.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned problems of the prior art by preventing vibration and tilting of a rod-shaped valve shaft.

The fluid control valve disclosed in Japanese Patent Application Laid-Open No. 56-96079 is configured to advance and retreat 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 shaft advances and retreats, the trajectory of the fixed portion between the leaf spring and the valve shaft draws an arc, so that the valve shaft cannot move immediately along the axis. For this reason, the axis of the valve is deviated from the center of the valve, and the flow control characteristics are not stable.

[Means for solving the problem]

In order to achieve the above object, the present invention is provided with a means for absorbing vibration in a direction perpendicular to the axis of the valve shaft.

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

Further, it may be sandwiched by a plurality of elastic plates mounted inside the valve shaft and the valve body.

It is necessary to limit the pressing force and the force for pinching to a force that does not hinder the axial movement of the valve shaft.

The holding member of the valve shaft used in such a fluid control valve has a disk having a hole through which the valve shaft is inserted in the center, an annular body formed around the disk, and one end fixed in a disk or ring state. ,
The other end has an elastic piece extending to the vicinity of the center of the hole, and the annular portion is fixed to the peripheral surface of the casing of the valve, and the tip of the elastic piece is pressed against the valve stem passing through the hole. It has become.

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

[Action]

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

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

Thus, a fluid control valve having a stable flow control characteristic free from the above-mentioned problems can be obtained.

When this is used for a fuel injection valve of an automobile, stable fuel metering becomes possible, the dynamic range is widened, and the controllability at the time of supplying minute fuel is improved.

Furthermore, when this is used for an idle air amount control valve of an automobile, the bypass air amount at the time of engine idling can be accurately controlled,
Elimination of engine stall due to insufficient air amount and abnormal rise in rotation due to excessive air amount are eliminated.

Although this type of control valve used for fluid control for automobiles is particularly susceptible to engine vibration, the use of the control valve of the present invention can eliminate the deterioration of flow characteristics caused by engine vibration.

The holding member is composed of a disk, an annular body, and elastic pieces fixed to them. It has a simple structure and can be assembled simply by fitting the annular state to the inner wall of the valve when assembling the control valve. Good nature.

〔Example〕

Hereinafter, the present invention will be described in detail based on an example in which the present invention is applied to an idle air amount control valve of an automobile.

FIG. 4 shows an application example of the present invention.
2, an engine provided with an exhaust pipe 3. The intake pipe 2 is provided with a throttle valve 4 and a throttle valve chamber 6 having a bypass passage 5. Further, an air flow meter 9 including a vane 7 for measuring the amount of air and a potentiometer 8 for converting the rotation angle of the vane 7 into an electric output is provided on the upstream side, and an air cleaner 10 is further installed on the upstream side. Is done. 11 is left in the middle of the passage connecting the intake pipe 2 and the exhaust pipe 3,
An EGR valve for returning a part of the displacement 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 electric output. 13 detects the number of revolutions of the engine 1,
The crank angle sensor 14, which converts the electrical output, receives various input signals, performs arithmetic processing on the input signals, and performs idle rotation control.
An arithmetic processing circuit (computer) for supplying a predetermined output to the fuel injection valve 15 and the fuel injection valve 16 controls the central portion of the electronic control of the engine. The input of the device of the present invention is also supplied thereto.

The idle rotation control device 15 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.

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.

The passage 102 of the valve case 101 communicates with the downstream side of the throttle valve, and the passage 103 communicates with the upstream side of the throttle valve. A central shaft 105 formed at the center of the valve 104 is held by a bearing 106 fixed to the valve case 101 so as to be movable in the axial direction. The valve 104 can completely close the space between the passage 102 and the passage 103 by contacting the seat 107 fixed to the valve case 101. A caulking member 105a is fixed to the central shaft 105, and the plate 108 and the plate 109 are caulked and fixed by the member 105a, and the inner ring portion of the diaphragm 110 is sandwiched between the plate 108 and the plate 109. ing.
Plates 108 and 109 are provided with orifices 111 leading to passage 103. The outer ring of the diaphragm 110 is sandwiched between the valve case 101 and the solenoid case 112. The bearing plate 129 is fixed to the cover 112 and has a cylindrical portion at the center thereof and receives the shaft 105 inserted therethrough. The solenoid case 112 houses and fixes a solenoid assembly 116. The solenoid assembly 116 is fixed to the plunger 114, a plunger 114 movable in the same direction as the central axis 105, a core 115 for sucking the plunger 114, an annular coil 116a formed so as to surround the core 115 and the plunger 114. A shaft 1 and a spring 1 for pushing the plunger 114 toward the valve 104
18 and adjust the set load of the spring 118 and the shaft 1
Adjustable screw 11 that supports 17 with its central bearing hole
These are all molded with a molding resin material 120. A rubber valve element 121 is fixed to the plunger 114. In addition, bearing plate 129 and plunger 114
A spring 113 for pressing the plunger 114 toward the adjust screw 119 is provided therebetween.

In such a configuration, the solenoid is a linear solenoid, and the displacement has a linear property with respect to the current.
As the current increases, the plunger 114 moves toward the core 115, and the valve pair 121 also moves together with the plunger 114, so that the valve body 121 moves away from the end of the central shaft 105. Then, the negative pressure of the passage 102 passes through the hole 122, passes through the passage 131 in the central shaft 105, the orifice 132 at the tip, and is introduced into the chamber 123 between the diaphragm 110 and the solenoid case 112. Although the negative pressure is slightly released through the orifice 111, the amount of the introduced negative pressure is large, so that the pressure in the chamber 123 becomes lower than the pressure in the passage 103, and the pressure difference between the passage 103 and the diaphragm 110 causes the diaphragm 110 to move to the left in the drawing. To open the valve 104 via the shaft 105. The balance of the negative pressure leaking from the orifice 111 and the negative pressure introduced from the valve 121 causes the central shaft 105 to move to the valve body 121 of the plunger 114.
The orifice 132 moves so as to be in close contact. When the orifice 132 is closed, the pressure tries to balance through the orifice 111. At the same time, 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 introduced into the chamber 123, and the diaphragm 110 moves to the left in the drawing. Thus, the valve 104 moves following the position to which the plunger 114 has moved, and is held at that position.

The springs 113, 118, and 130 are operated by the valve 104, the valve
(Ie, the plunger 114) has the effect of preventing the plunger 114 from moving.
9 is effective in adjusting the variation in the load on the production and assembly of the spring 118.

In addition to fully closing the valve when no power is supplied, the device is closed even if the diaphragm 110 is torn, and the valve is not opened as long as the valve 121 is closed, even if the orifice 111 is stumbled. . Thus, when each part fails, there is an effect that the valve 104 is closed.

What is important here is that the central shaft 106 is supported by the bearing 106 and the bearing plate 129 and is axially urged by the above-mentioned spring 113, 118 or 130, but the radial vibration of the valve 104 and the central shaft 105 is not sufficient. Cannot be suppressed.

Therefore, in this embodiment, the 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 through which the central shaft 105 is inserted at the center of the disk portion 16. Further, the disk portion 16 has a leaf spring 14 fixed by a rivet 17. The leaf spring 14 is configured to come into contact with the outer surface of the central shaft 105 with a predetermined pressing force when the central shaft 105 is inserted into the hole.

The cup-shaped vibration suppressing member 13 thus configured is fixed thereto by fitting the outer annular portion 15 to the inner annular portion of the valve case 101.

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

The solenoid assembly 116 is housed inside a solenoid case 112 with a seal ring 131 interposed therebetween, and the tip of the case 112 is fixed to the surface of the mold resin of the solenoid assembly 116 by caulking.

A rubber valve element 121 is molded at the tip of the shaft 117, and this is press-fitted into a central hole of the plunger 114 to fix them together.

Spring 118 around shaft 117 of this plunger assembly
Install this shaft 117 and adjust
While inserting the plunger 114 into the solenoid 116
Loosely fit in the center hole of a.

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

On the other hand, a caulking metal 105a is fixed to the central shaft 105, and the plate 108, the diaphragm 110, and the plate 109 are set to the metal fittings from the left side in FIG. 1 in this order, and the left end of the metal fitting is bent outward to add three pieces. Tighten and fix. Next, the vibration suppressing member is inserted through the central axis, and thereafter, the valve 104 is molded and fixed at a predetermined position of the central axis by molding. The center shaft assembly thus obtained has the outer cylindrical portion of the vibration suppressing member 13 with the valve 104 side end inserted into the hole of the bearing 106 around which the spring 130 is disposed, and the valve case 10 having the same shape.
Press into the inner surface of 1 and fix.

While holding the outer peripheral edge of the diaphragm 110 on a flat portion formed on the peripheral end surface of the opening of the valve case 101, the central shaft 105
Is inserted into the center hole of the plunger from the bearing hole of the bearing plate 129, and the leading end thereof is brought into contact with the end surface of the valve body 121, and the opening-side peripheral end surface of the solenoid case 112 is overlapped with the peripheral edge of the diaphragm 110. Then, the periphery of the end of the valve case 101 is bent inward and caulked over the periphery of the end of the solenoid case 112, and the two are fixed at this portion with the diaphragm 110 sandwiched therebetween.

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

Further, the leaf spring 14 applies a pressing force in a direction perpendicular to the axis, that is, a so-called side force to the center axis 105, and as a result, the center axis 10
5 and the cylindrical portion forming the bearing of the bearing plate 129 and the bearing 10
Press against the inner peripheral surface of the bearing hole of No. 6 with a specified side force. Thus, the central shaft 105 is not affected as an independent mass by vibrations transmitted from the engine, but is affected by vibration as a part of a valve assembly or a member of a solenoid assembly. The body does not vibrate.

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 central shaft assembly cannot be moved in the axial direction, so it is necessary to use a correspondingly strong spring. The spring force should be determined appropriately depending on the size of the side force. In any case, if the force of the spring 118 is increased, the electromagnetic force for attracting the plunger 114 also needs to be increased. Therefore, the spring force should be set in consideration of the electromagnetic attractive force.

In FIG. 1, reference numeral 120 denotes a connection terminal molded with resin, which is connected to an external power supply terminal and supplies electric power to the solenoid 116a.

Reference numeral 122 denotes a blind plug that blocks the outside after setting the ASC.

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

Hereinafter, an alternative to the vibration suppressing member 13 will be described. In FIG. 2, the member forming the leaf spring 14 is fixed to the disk portion 16 with the rivet 17, but it may be fixed by spot welding instead of the rivet 17.

FIG. 3 shows a structure constituted by linear springs.
The spring 14a is composed of a curved portion which is pulled on the central shaft 105 and a wound spring portion which is held by a resilient force on the peripheral edge of the bottom surface of the cup-shaped member. The cap member is held on the inner peripheral edge of the cup-shaped member by the spreading force when the cap member is released.

FIG. 5 shows an example in which a member having two symmetrically formed leaf springs is sandwiched between cut-and-raised pieces formed in the disk portion 16, and the cut-and-raised piece 16a is fixed by caulking. It is.

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

In this case, since the center shaft 105 is held in a state sandwiched between the leaf spring pieces 14c and 14d, the center shaft is not pressed against the bearing 106 or the bearing plate, and the axial movement is smoother.

Next, with reference to FIGS. 7 and 8, an improvement in the shape of the tip of the central shaft 105 and the orifice 132 formed thereon will be described.

In this embodiment, the tip of the central shaft 105 is formed in a conical shape,
The contact portion with the valve body 121 is configured to be a line contact, not a surface.

Specifically, the diameter of the orifice is 1.2 mm, and the inclination angle of the conical surface is 7
As ゜, the contact between the valve element 121 and the orifice portion is made substantially in contact with a circular line.

Comparing this with the case of the conventional surface contact by the suction force, as shown in FIG. 9, as the conventional stroke is increased, the suction force between the valve element 121 and the central shaft 105 is once reduced by about 30%. In this example, the adsorption power did not increase, and the decrease was quickened, while the degree (about 3 g) increased.

Conventionally, the suction force is too large and the diaphragm 110 needs to be largely displaced in order to separate the two, and as a result, the distance between the valve body 121 and the tip of the central shaft 105 after being separated becomes too large, and the valve 104 is As a result, the air flow control characteristics were unnecessarily displaced, causing an overshoot phenomenon.

In this embodiment, since the suction force between the two members could be made very small, this overshooting phenomenon could be eliminated.

As a result, even when the side force acts on the central axis, the axial movement of the central axis does not become unstable, and a technique for applying the side force can be realized.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, the vibration with respect to the radial direction of a center axis | shaft is suppressed and an unstable movement of a valve can be eliminated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a control valve according to an embodiment of the present invention, and FIG.
FIG. 3 is a perspective view of the vibration suppressing member of FIG. 1, FIG. 3 is a perspective view of another embodiment of the vibration suppressing member, FIG. 4 is a system diagram showing an application example of the control valve according to the present invention, and FIG. Is a perspective view showing still another embodiment of the vibration suppressing member, FIG. 6 is a cross-sectional view of a main part of a control valve using the vibration control member of FIG. 5, and FIG. 7 is an improved structure of an orifice portion of the control valve. FIG. 8 is a partial enlarged cross-sectional view, and FIG. 8 is an explanatory view of the effect of the improved orifice structure of FIG. 13: Vibration suppression member, 14: Leaf spring, 101: Valve case, 104: Valve, 105: Central axis, 107: Valve shutter, 110: Diaphragm, 112: Solenoid case, 114: Plunger , 116 ... Solenoid assembly, 12
1… Valve body.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koichiro Yamada 2520 Oji Takaba, Katsuta-shi, Ibaraki Inside the Sawa Plant of Hitachi, Ltd. No. 3 Hitachi Automotive Engineering Co., Ltd. (72) Inventor Hiroaki Saeki 2477 Kashima Yatsu, Odai Kodai, Katsuta-shi, Ibaraki Prefecture No. 3 Hitachi Automotive Engineering Co., Ltd. (72) Inventor Honma Hideki 2477 Kashima Yatsu, Kata-shi, Ibaraki Pref.Hitachi Automotive Engineering Co., Ltd. (56) References JP-A-64-24133 (JP, A) JP-A-58-30524 (JP, A) Actually open 58-1759 (JP, U) Actually open 61-197326 (JP, U) Actually open 50-107848 (JP, U) Actually open 62-111 326 (JP, U) Actually open 60-194625 (JP, U)

Claims (1)

(57) [Claims] 1. An annular diaphragm whose outer periphery is sandwiched between an open end of a cylindrical valve case and an electromagnetic solenoid, and one end of a hollow shaft is provided at the center of the diaphragm at the electromagnetic solenoid. It is supported by a bearing plate, and the other end is guided by a bearing provided inside the cylindrical valve case, and is formed in the cylindrical valve case between the diaphragm and the inside of the cylindrical valve case. An air flow control unit is formed by the valve seat and the valve fixed to the shaft, and the cylindrical valve case has an air intake port on the diaphragm side with the air flow control unit interposed therebetween. Air discharge ports are respectively formed in the air discharge ports and a space on the electromagnetic solenoid side of the diaphragm by the hollow shaft. The opening of the hollow shaft on the side of the electromagnetic solenoid is closed by a valve body formed at the end of a plunger of the electromagnetic solenoid, and the plunger is urged toward the diaphragm by a spring. The hollow shaft is urged to the plunger side by another spring, and when the electromagnetic solenoid is not energized, the valve is attached to the valve seat against the force of the another spring. The cup-shaped member is configured so that a force in a pressing direction is applied, and a cup-shaped member whose center is penetrated by the shaft is fixed to a position between the diaphragm and the valve in the cylindrical valve case. The cup-shaped member holds a metal elastic member whose tip is pressed against the outer periphery of the shaft. Car of the idle speed control valve.