JPH0422140Y2 - - Google Patents

Description

[Detailed description of the invention] A. Purpose of the invention (1) Industrial application field This invention relates to a fluid control valve that controls the flow of fluid. More specifically, it relates to a fluid control valve that controls the flow of fluid. The present invention relates to a fluid control valve suitable for a proportional fluid control valve.

(2) Prior Art To prevent the differential pressure of the working fluid from acting on the valve body that opens and closes the valve hole that communicates the inflow and outflow passages of the working fluid, which prevents the valve body from being able to open and close accurately. , a fluid control valve that has a diaphragm chamber defined by a diaphragm on the outflow path (or inflow path) side and cancels the pressure by guiding the pressure in the inflow path (or outflow path) to the diaphragm chamber is disclosed in Japanese Patent Application Laid-open No. This method is already known from JP-A No. 56-70182, Japanese Unexamined Patent Publication No. 57-1881, and the like.

However, in these techniques, if the working fluid contains alcohol such as gas holes, the diaphragm may swell and its effective diameter may change, making it impossible to perform normal pressure cancellation. Additionally, the diaphragm itself has variations in its effective diameter due to manufacturing process, which causes variations in the pressure cancel function.

(3) Problems to be solved by the invention In view of the above-mentioned circumstances, the present invention aims to provide a fluid control valve that can exhibit a normal pressure cancel function by suppressing fluctuations in the effective diameter of the diaphragm as much as possible. The purpose is to

B. Structure of the invention (1) Means for solving the problems According to the invention, the invention has a valve body that opens and closes a valve hole that communicates one flow path of the working fluid with the other flow path,
In a fluid control valve, a diaphragm chamber defined by a diaphragm communicating with the valve body is provided on one side of the flow path, and the pressure on the other side of the flow path is guided to the diaphragm chamber to cancel the pressure. The pressure-responsive portion of the diaphragm is formed long in the axial direction, and the inner and outer diameter sides of the pressure-responsive portion of the diaphragm are in contact with guides that maintain a constant diameter.

(2) Effect By attaching the above guide, even if the diaphragm swells, the effective diameter of the diaphragm is mechanically determined by the inner and outer diameters of the guide, and the effective diameter does not change. Therefore, variations in the flow rate of the working fluid due to the operation of the diaphragm are suppressed as much as possible.

(3) Embodiment An embodiment of the fluid control valve of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of a fluid control solenoid valve V, which is used for idle rotation control, air-fuel ratio control, EGR control, etc. in internal combustion engines of automobiles.

This fluid control solenoid valve V includes a fluid control section 1 that controls the flow of fluid by opening and closing operations of a valve body, and an electromagnetic actuating section 2 that operates the valve body of the fluid control section 1 by electromagnetic force.

Hereinafter, the configurations of the fluid control section 1 and the electromagnetic actuation section 2 will be generally explained.

In the fluid control unit 1, an inflow path 11 and an outflow path 12 are formed in a valve box 10, and these inflow path 11 and outflow path 12 communicate with each other through a valve hole 13.
A valve seat 14 is formed around the valve hole 13 on which a valve body 16 (described later) is seated.

The valve body 16 includes a valve body 19 consisting of a disc-shaped valve plate 17 facing the valve seat 14 and a cylindrical portion 18 integrally connected to the valve plate 17, and a rubber body fixed to the front surface of the valve plate 17. The seal body 20 is made of Valve plate 1
The pressure-receiving area of the back side of the valve 7, that is, the side facing the outflow path 12, is made larger than the pressure-receiving area of the front side, that is, the side facing the inflow path 11. An inner hole 19a is formed in the valve body 19 so as to penetrate in the axial direction and fit into a shaft 24, which will be described later. The seal body 20 is seated on the valve seat 14 to form a fluid seal.

The valve body 16 is fixed to one end of a long shaft 24 with a retaining ring 22 . The retaining ring 22 is made of a thin steel plate, and is a JIS E-type retaining ring or a special retaining ring, and is elastically fitted into the groove of the shaft 24. The diameter of the shaft 24, including the collar, is changed as appropriate in order to attach the valve body 16 and other members constituting the electromagnetic valve. The valve body 16 is fixed to the shaft 24 by shrink-fitting it to the outer diameter of the shaft 24 using a circular hole 19a formed in the valve body member 19, in addition to the retaining ring 22 that is locked to the shaft 24. It may be fixed, or it may be provided with a fixing pin (not shown) that passes through the tip of the valve body 19 and the shaft 24.

The shaft 24 is supported by leaf springs 25, 26 and is free to move in the axial direction. That is, the leaf springs 25 and 26 are made of thin metal disks, each having a circular hole in the center, the peripheral edge of which is held by a frame such as a valve box or a housing 35 to be described later, and the center hole is A shaft 24 is inserted and supported.

A diaphragm device 27 mainly including a diaphragm 28 is integrally attached to the rear end of the valve body 19 of the valve body 16, forming a diaphragm chamber 28A that communicates with the inflow path 11 via a pressure guiding path 32, which will be described later. do.

The diaphragm device 27 includes a diaphragm 28 , an outer holder 29 , and an inner holder 30 made of rubber. The outer circumferential and inner circumferential holders 29 and 30 are made of metal or hard synthetic resin, and the outer circumferential holder 29 is engaged with and held by the valve box 10, and the inner circumferential holder 30 is fitted and fixed to the shaft 24. together with valve body part 1
9 is airtightly inserted into the rear end.

Separately from this diaphragm device 27, an intervening passage 31 having a pressure guiding passage 32, which will be described later, is connected to the rear end of the inner circumferential holder 30 and interposed between it and the leaf spring 25. Therefore, if the inner periphery holding body 30 also serves as the function of this intervening member 31, it can be omitted.

Pressure guiding passage 32 communicating with diaphragm chamber 28A
are formed on the valve body 16 and the diaphragm device 27. More specifically, the inner hole 19a of the valve body 19
A pressure guiding passage 32a of the valve body is recessed in a cross shape facing the inner circumferential holder 30.
A pressure guiding passage 32b is recessed in communication with the interposed member 31, and a pressure guiding passage 32c is similarly recessed in the interposed member 31. The pressure guiding passage 32a of the valve body 16 communicates with the inflow passage 11 via its inlet, and in the interposed member 31 communicates with the diaphragm chamber 28A via its outlet.

The diaphragm 28 of the diaphragm device 27 is of a so-called bellophragm type, and an outer guide body 33 for regulating the outer diameter of the diaphragm 28 is disposed separately from the valve body 10. Further, the outer peripheral surface of the cylindrical portion 18 of the valve body 16 regulates the inner diameter of the diaphragm 28. Thereby, the diameters of the inner and outer surfaces of the diaphragm 28 are kept constant.

The above fluid control unit 1 is attached to the valve box 10 by fitting the outer periphery holder 29 of the diaphragm device 27,
These are fixed by caulking a housing extending from an electromagnetic actuating section 2, which will be described later.

In the electromagnetic actuator 2, a mechanism for moving the shaft 24 in the axial direction by electromagnetic force is housed in a metal cylindrical housing 35. That is,
A movable core 36 made of a magnetic material is fixed to the middle part of the shaft 24, and a cylindrical fixed core 37 made of a magnetic material is located opposite to the movable core 36 in its inner hole 3.
7a so as to movably hold the shaft 24.

An electromagnetic coil 40 wound around a bobbin 39 made of synthetic resin is disposed around the outer periphery of the fixed core 37 .
Further, a molded synthetic resin cover 41 that covers the electromagnetic coil 40 is disposed in the radial direction surrounding the bobbin 39 via the joint surface 42 . An annular seal groove 43 is provided on both sides of the joint surface 42 in the axial direction.
is formed, and an annular seal member 44 is mounted within this seal groove 43.

A socket portion 46 projecting radially outward is integrally provided at one end of the cover 41. A terminal 46a electrically connected to the electromagnetic coil 40 is accommodated in this socket portion 46.
A plug (not shown) leading to an external power source is fitted using the guide.

A first yoke 47 and a second yoke 48 made of a magnetic material are disposed on both sides of the bobbin 39 and cover 41 so as to sandwich them, and the first yoke 47 is fitted around the movable core 36 so as to be movable. The second yoke 48 is fitted onto the end of the fixed core 37 .

Among the above members, the housing 35, the first yoke 4
7. The movable core 36, the fixed core 37, and the second yoke 48 are annular and form a magnetic path.

The rear end of the housing 35 is caulked to hold the adjuster holder 50, and the leaf spring 26 is sandwiched and held between the rear end surface of the second yoke 48 and the front end surface of the adjuster holder 50. A spring seat 51 is fitted onto the shaft 24 in contact with the leaf spring 26, and is prevented from coming off with a retaining ring 52.

An inner thread 53 is cut on the inner periphery of the inner cylindrical portion 50a of the adjuster holder 50, and an adjuster 54 having an outer thread 54a is screwed onto the inner thread 53.

A coil spring 55 is interposed between the front spring seat 54b of the adjuster 54 and the spring seat 51,
This urging force presses the valve body 16 against the valve seat 14 via the spring seat 51 and the shaft 24.

In addition, in order to attach this electromagnetic valve V, a mounting rib 60 is provided attached to this electromagnetic valve V.
This is merely an additional feature in this solenoid valve.

Further, although a leaf spring is used as a support structure for the shaft 24, other suitable bearings may be used, and this point is not essential to the present invention.

This embodiment is further characterized by a structure for regulating the inner and outer diameters of the bellows-shaped diaphragm 28 used in the diaphragm device 27 (inner and outer diameter regulating structure), and the detailed structure thereof is shown in FIG.

The diaphragm 28 is formed into an annular shape made of an elastic material, and consists of gripping parts 28a and 28b fixed to holders 29 and 30 on the outer and inner peripheries, and a pressure responsive part 28c which is the main part of the diaphragm function.

The pressure responsive portion 28c is long in the axial direction, and is formed to have a so-called trunk length. Therefore, the diaphragm 28 can be displaced over a large range with respect to the pressure introduced into the diaphragm chamber 28A.

In the gripping portions 28a and 28b, an outer gripping groove 28d is formed on the outer peripheral edge thereof, and an inner gripping groove 28d is formed on the inner peripheral edge thereof.
8e is recessed. Further, a plurality of protrusions 28f are continuously formed in an annular shape on the side surface of the outer peripheral edge.

The outer periphery holder 29 has a ring shape, and a locking protrusion 29a is continuously formed on its inner circumference, and the outer gripping groove 28d of the diaphragm 28 is formed in the locking protrusion 29a.
is oppressively applied.

The inner circumferential holder 30 has a substantially cylindrical shape, and a locking protrusion 30a is continuously formed on the outer periphery of the end thereof. The inner gripping groove 28e of the diaphragm 28 is elastically attached to the locking protrusion 30b. This inner peripheral holder 30 has an inner hole and is forcibly fitted onto the shaft 24.

The inner peripheral holder 30 is further provided with a cross-shaped pressure guiding passage 32b recessed in the axial direction facing the inner hole. This pressure guiding passage 32b is connected to the pressure guiding passage 32a of the valve body 16 and the pressure guiding passage 32c of the intervening member 31,
It forms a part of a pressure guiding passage 32 that communicates from the inflow passage 11 to the diaphragm chamber 28A. Note that if the pressure guiding passage 32 is formed in the shaft 24, it goes without saying that this pressure guiding passage 32b is unnecessary.

Such a diaphragm device 27 is constructed by fitting the locking protrusions 29a, 30a of the outer and inner periphery holders 29, 30 into the gripping grooves 28d, 28e of the diaphragm 28, and fixing the fitting portions by baking. The whole is integrated.

The outer guide body 33 has an annular shape, is fitted and held inside the valve box 10, and has its inner peripheral surface abutted against the outer surface of the pressure responsive portion 28c of the diaphragm 28. Thereby, the outer diameter of the diaphragm 28 is restricted.

On the other hand, the valve body portion 19 of the valve body 16 also serves to regulate the inner diameter of the pressure responsive portion 28c of the diaphragm 28.
That is, the outer diameter of the cylindrical portion 18 of the valve body portion 19 is enlarged, and the inner surface of the pressure responsive portion 28c is brought into contact with the outer circumferential surface of the cylindrical portion 18, whereby the diaphragm 28
The inner diameter of the

The operation of this fluid control solenoid valve V will be explained.

When no current is supplied to the electromagnetic coil 40 and the electromagnetic coil 40 is in a non-excited (demagnetized) state, the shaft 24 and movable core 36 are urged to the illustrated positions by the spring bias of the spring 55, and the valve body 16 The seal body 20 is seated on the valve seat 14. Therefore, since the valve hole 13 is closed and the communication between the inflow path 11 and the outflow path 12 is cut off, there is no fluid flow.

In this state, when the pressure in the inflow path 11 increases (or when the pressure in the outflow path 12 decreases), the pressure in the inflow path 11 is guided to the diaphragm chamber 28A via the pressure guiding path 32. , the difference in fluid pressure acting on the front and rear surfaces of the valve plate 17 is canceled out, and no undesirable force is applied to the valve plate 17. Therefore, the valve body 16 is closed only by the biasing force of the spring 55.

When a current is supplied to the electromagnetic coil 40 via the terminal 46a, the electromagnetic coil 40 becomes excited, and the magnetic flux from the electromagnetic coil 40 is applied to the housing 35 and the first
A closed loop magnetic path returning to the housing 35 via the yoke 47, the movable core 36, the fixed core 37, and the second yoke 28 is formed, and the movable core 36 and the fixed core 37
A magnetic attraction force corresponding to the current value is generated between the two.

As the valve body 16 separates from the valve seat 14, the valve hole opens and fluid flows from the inflow path 11 to the outflow path 12.

At this time, as described above, the differential pressure of the fluid acting on the valve plate 17 is offset by the fluid pressure introduced into the diaphragm chamber 18A, so that no undesirable force is applied to the valve plate 17, and therefore the valve plate 16 can obtain an opening that is exactly proportional to the current supplied to the electromagnetic coil 40. Furthermore, since the pressure-receiving area on the back surface of the valve plate 17 is larger than the pressure-receiving area on the front surface, fluctuations in the flow rate at the initial stage of opening of the valve body 16 are suppressed.
In addition, the proportionality of the opening degree of the valve body 16 with energization is improved, and together with the action of the diaphragm device 17 described above, the opening degree can be adjusted more accurately.

In such a solenoid valve V, the diaphragm 2
The effective diameter of valve 8 is uniformly determined by the inner diameter of the outer guide body 33 and the outer diameter of the valve body portion 19 which also serves as the inner guide body, and the effective diameter does not change even if the diaphragm 28 swells. Therefore, the diaphragm 28 can maintain its intended function.

Note that the protrusions 28f on the outer edge of the diaphragm 28 are brought into contact with the end faces of the outer guide body 33 and the valve box 10 to ensure airtightness and prevent leakage of working fluid from these parts.

FIG. 3 shows another embodiment of the structure for regulating the inner and outer diameters of the diaphragm. In the figures, the same reference numerals are given to the same members as in the previous embodiment.

In this embodiment, the inner guide body 34 is provided separately from the valve body 16. That is, the rear part of the cylindrical part 18 of the valve body part 19 is recessed, and the annular inner guide body 34 is fitted and attached to this. The outer peripheral surface of the inner guide body 34 regulates the inner diameter of the pressure responsive portion 28c of the diaphragm 28. The outer guide body 33' engages with the valve body 10 and
Together with this, it forms part of the frame.

Further, in the inner peripheral holding body 30', it is further extended to the rear and also serves as an intervening member. Along with this, the pressure guiding passage 32b is also extended, and an outlet hole 30b opening facing the diaphragm chamber 28A is bored in the peripheral wall.

In the above embodiments, an electromagnetically driven electromagnetic valve was explained as an example, but the valve according to the present invention is not limited to such an electromagnetic valve, and may be an electric, mechanical or fluid-driven valve. Of course, it can also be used for valves.

C. Effects of the invention The fluid control valve of the invention has a valve body that opens and closes a valve hole that communicates one flow path of working fluid with the other flow path, and the valve body is provided on one side of the flow path. In a fluid control valve that has a diaphragm chamber defined by interlocking diaphragms and cancels pressure by guiding the pressure on the other side of the flow path to the diaphragm chamber, the pressure responsive portion of the diaphragm is long in the axial direction. The pressure-responsive part of the diaphragm has a structure in which the inner and outer diameter sides of the pressure-responsive part are in contact with a guide that maintains a constant diameter, so the length of the pressure-responsive part of the diaphragm further improves the ability of the pressure cancel function. Moreover, due to its inner and outer diameter regulating structure, the effective diameter is constant, and more accurate pressure canceling function can be achieved. Variations in the inner and outer diameters due to the manufacture of the diaphragm are absorbed by the inner and outer guide bodies, making it possible to obtain a uniform effective diameter.

[Brief explanation of the drawing]

The drawings show an embodiment of the fluid control valve of the present invention, FIG. 1 is an overall vertical sectional view of one embodiment, FIG. 2 is an enlarged sectional view of the main part, and FIG. 3 is a partial view of another embodiment. FIG. 11... Inflow path, 12... Outflow path, 13... Valve hole, 14... Valve seat, 16... Valve body, 28... Diaphragm, 28A... Diaphragm chamber, 28c...
...Pressure responsive part, 30... Inner circumference holding body, 33... Outer guide body.

Claims (1)

[Claims for Utility Model Registration] A diaphragm having a valve body that opens and closes a valve hole that communicates one flow path of working fluid with another flow path, and which is interlocked with the valve body on one side of the flow path. A fluid control valve is provided with a diaphragm chamber defined by a diaphragm chamber, and performs pressure cancellation by guiding the pressure on the other side of the flow path to the diaphragm chamber, wherein the pressure responsive portion of the diaphragm is formed long in the axial direction; A fluid control valve characterized in that the inner and outer diameter sides of a pressure-responsive part of a diaphragm are in contact with a guide that maintains a constant diameter.