JPH05248567A - Solenoid valve - Google Patents

Abstract

PURPOSE:To make a coil compact by applying the pushing-up force of a differential pressure sensitive body to the travel of a core, and reduce cost by simplifying a structure via the elimination of a collar for increasing magnetic efficiency. CONSTITUTION:In a valve performing the open and close control of a valve port for a fluid flow with a differential pressure sensitive body 23, a plunger 36 is provided within a guide cylinder section 29 for the body 23, together with a main spring 37 for energizing the plunger 36 on a resilient force less than the electromagnetic force of a coil. In addition, a core 33 for causing the lower end of the plunger 36 to contact the guide cylinder section 29 is so laid on the coil center axis as to be independent of an electromagnetic force, and an auxiliary spring 35 for energizing the core 33 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve for reducing the stroke of a plunger for opening and closing a pilot port and simplifying the structure of a solenoid for downsizing.

[0002]

2. Description of the Related Art Conventionally, as a pilot type solenoid valve for cutting off a fluid, as shown in FIG. 3, a stroke L2 of a plunger d moved by a coil c with respect to a stroke L1 of a diaphragm b for opening and closing a valve opening a. Is set to a large value.

However, in this type of solenoid valve, since the stroke L2 of the plunger d is large and is directly moved, the coil c is inevitably increased in size in order to increase the electromagnetic force. When the coil c is miniaturized, in order to compensate for this electromagnetic force and obtain the stroke L2, the yoke f in this coil c must be provided with a collar f to enhance the magnetic efficiency. It has a drawback that the number of points and the assembling process increase and the cost rises.

[0004]

SUMMARY OF THE INVENTION According to the present invention, the push-up force of the differential pressure receiving member is applied to the movement of the core to reduce the size of the coil, and the collar for increasing the magnetic efficiency is not required to simplify the structure and reduce the cost. It is intended to provide a solenoid valve that is reduced.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of increasing the size and cost of a coil based on the above-mentioned prior art, and forms the core in a neutral state with respect to the electromagnetic force of the coil, and senses the differential pressure of the core. The purpose of this invention is to solve the above-mentioned drawbacks by providing a solenoid valve whose purpose is to push it up by the body.

Hereinafter, the solenoid valve according to the present invention comprises a valve box, a coil, a differential pressure sensing body, a plunger and a core.

The valve box has a valve port communicating the inlet and outlet of fluid, and a differential pressure sensing body is provided facing the valve seat of the valve port so as to be seated. The differential pressure sensing body has a pilot port. And the bleed port is provided on the differential pressure sensing body or the valve box.

The plunger is arranged in the guide cylinder portion provided on the differential pressure receiving body so as to face the pilot port, and
A main spring is provided that is moved in a direction away from the pilot port by the electromagnetic force of the coil and that urges the plunger toward the pilot port side with an elastic force smaller than the electromagnetic force of the coil.

The core is neutrally held on the center axis of the coil by the electromagnetic force of the coil, and the lower end of the core is brought into contact with the upper end of the guide cylinder of the differential pressure receiving body, and the core is given a predetermined elastic force. An auxiliary spring is provided to urge the differential pressure receiving side toward the side.

[0010]

In the present invention, when the coil is energized, the core is magnetized by the electromagnetic force generated by the coil, whereby the plunger is attracted by the core in the direction away from the pilot port. The pilot port opens, and the fluid in the pilot chamber flows out to the secondary pressure chamber. As a result, the differential pressure sensing body is pushed up, and the diaphragm separates from the valve seat and the valve port opens.

In such a state, until the plunger is attracted to the core, the core is in a neutral state with respect to the electromagnetic force of the coil, after which the plunger is attracted to the core and the pilot port is opened. The differential pressure between the primary pressure chamber and the pilot chamber is generated by the differential pressure, and the pushing force that pushes up the receiving body is applied to the core via the guide tube, and the core feels the differential pressure against the elastic force of the auxiliary spring. It moves upward in conjunction with the receiver.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 is a solenoid valve according to the present invention, in which an inlet 3 communicating with a primary pressure chamber 2 and a secondary pressure chamber 4 are communicated with each other. Forming an outlet 5 for the primary pressure chamber 2 and the secondary pressure chamber 4
Is partitioned by a partition wall 6, and a valve port 7 that connects the primary pressure chamber 2 and the secondary pressure chamber 4 is formed in the partition wall 6, and a mounting hole 8 is formed coaxially with the valve port 7. It forms a valve box 9.

A solenoid 10 is mounted in the mounting hole 8 of the valve box 9. The solenoid 10 has an opening at the lower end side, and
A lower mounting portion 12 to be fitted with the mounting hole 8 is integrally formed on the outer side of the opening edge of the hollow cylindrical portion 11 formed by closing the upper end side, and a bobbin is formed at an intermediate portion of the hollow cylindrical portion 11. A part (13) is integrally formed, and a flange part (14) is integrally formed outward on the upper end side to form a coil mounting body (15).

An annular coil 16 is wound around the bobbin portion 13 of the coil mounting body 15.

Reference numeral 17 is a yoke which forms a magnetic path made of a magnetic material which constitutes the solenoid 10. The yoke 17 is formed by bending a plate member having a predetermined width in a U-shaped cross section.
A slot 21 into which the coil mounting body 15 is inserted from the side, on the upper wall portion 19 and the lower wall portion 20 of the yoke body 18,
21a are formed respectively.

Then, the coil mounting body 15 on which the coil 16 is wound is inserted from the opening side of the slots 21 and 21a of the yoke 17 to assemble the solenoid 10 integrally.

Further, although the yoke body 18 is formed in a U-shaped cross section in the above embodiment, the shape is not limited to this. For example, the yoke body 18 is formed into a cylindrical shape, and the upper end of the yoke body 18 is formed. The upper wall portion 19 is integrally formed on the side, and the lower wall portion 20 on the lower end side is separately formed. The hollow cylindrical portion 11 of the coil mounting body 15 is inserted into the upper wall portion 19 and the lower wall portion 20. The insertion holes 22 and 22a should be drilled to form the yoke 17,
The yoke 17 may be divided into two parts in the axial direction on the left and right sides, and the divided yoke 17 may be mounted on the coil mounting body 15 so as to surround the coil 16.

The coil mounting body 15 has a bobbin portion 13 and a collar portion 14 attached thereto.
In the case where the yoke is not formed, in the case of the yoke 17 having a U-shaped cross section as described above, instead of the slots 21 and 21a, the hollow cylinder
It suffices to drill the insertion holes 22 and 22a into which 11 should be inserted.
Further, if it is a cylindrical yoke 17, it is not necessary to divide it. In short, the hollow cylindrical portion 11 of the coil mounting body 15 is inserted into the insertion holes 22 and 22a of the yoke 17, and the hollow cylindrical portion 11 protruding upward from the yoke 17 is inserted. A nut member (not shown) is screwed onto the yoke 17
It is also possible to integrally combine the coil mounting body 15 and the coil mounting body 15.

Reference numeral 23 is a differential pressure receiving body, and the differential pressure receiving body 23 is a diaphragm receiving body having a pilot port 24 at its center.
A diaphragm 26 made of an elastically deformable material is provided on the lower surface of 25, and the outer peripheral edge portion of the diaphragm 26 is clamped by the lower mounting portion 12 of the solenoid 10 and the seat surface 27 of the mounting hole 8 of the valve box 9, and the valve opening 7 The diaphragm 26 is disposed so as to be seated on the valve seat 28 at the upper end of the.

Further, the diaphragm 26 in the differential pressure sensitive body 23
The outer diameter of the pilot port 24 from the outside
A cylindrical guide tube portion 29 having a smaller diameter than the inner diameter of 11 is integrally projected upward, and a communication hole 30 is formed at an appropriate position on the side wall of the guide tube portion 29.

As the position of the upper end portion of the guide cylinder portion 29, in this embodiment, the diaphragm 26 of the differential pressure sensing body 23 is the valve seat.
The lower wall portion 20 of the yoke 17 when seated on the 28
It has substantially the same height as the lower surface 20a of the.

In addition, the differential pressure sensitive body 23 has an inlet 3 and a differential pressure sensitive body.
A bleed port 32 having a smaller diameter than the pilot port 24 communicating with the pilot chamber 31 above 23 is bored.

The bleed port 32 may be provided so that the inlet 3 and the pilot chamber 31 communicate with each other, and may be provided in the valve box 9 itself, for example.

33 is a core, and the core 33 is a solenoid 10
In the hollow cylindrical portion 11 of the coil mounting body 15 in the above, the lower end of the core body 34 made of a magnetic material having a cylindrical shape is arranged so as to be vertically movable (on the central axis of the coil 16). The axial length of the core main body 34 is set so that the upper end of the core main body 34 is substantially flush with the upper surface 19a of the upper wall portion 19 of the yoke 17 while being in contact with the upper end of the guide tubular portion 29.

By arranging the core 33 in such a state, when the coil 16 is energized, the core 33 does not move up and down and is kept in a neutral state against electromagnetic force.

In the present embodiment, the upper and lower ends of the core 33 are described to have substantially the same height as the upper and lower surfaces 19a and 20a of the yoke 17, respectively. Until the jar 36 is attracted to the core 33, it may be provided so as to be held neutral to the electromagnetic force when the coil 16 is energized. For example, the upper and lower ends of the core 33 are respectively the upper and lower surfaces of the yoke 17.
Even when they are projected from 19a and 20a, the neutral state is maintained if the projection heights are substantially the same.

Reference numeral 35 denotes an auxiliary spring, which is interposed between the upper end of the core 33 and the upper end of the hollow cylindrical portion 11 and urges the core 33 downward with a predetermined elastic force F1. And is brought into contact with the upper end of the guide tube portion 29.

36 is a plunger made of a magnetic material,
The plunger 36 is vertically movably arranged in the guide tube portion 29 of the differential pressure sensing body 23, and the elastic force between the plunger 36 and the core 33 is smaller than the suction force generated when the coil 16 is energized. A main spring 37 that urges downward with a force F2 is interposed.

Further, as the elastic force F2 of the main spring 37, the force applied in the valve closing direction due to the difference in pressure receiving area between the upper and lower sides of the plunger 36 is naturally taken into consideration in design.

Reference numeral 38 in the drawing denotes a valve element mounted on the lower surface of the plunger 36.

Here, the relationship between the elastic force F1 of the auxiliary spring 35 and the elastic force F2 of the main spring 37 is naturally set to "elastic force F1> elastic force F2-the weight of the core 33" by design. The push-up force F3 that pushes up the differential pressure sensitive body 23
, The plunger 36 is attracted to the core 33, and the differential pressure sensitive member 23
Regarding the relationship with the pressing force F4 that pushes down the core 33 by the coil 16 when the core 33 is pushed up by
Although “pushing force F3> pressing force F4 + elastic force F1” is satisfied, it is naturally designed to minimize “pressing force F4 + elastic force F1”.

The operation of the solenoid valve according to the present invention will be described. First, when the coil 16 is not energized, the elastic force F1 of the auxiliary spring 35 pushes down the core 33 toward the differential pressure receiving body 23, and the core 33 is pushed down. Guide tube portion 29 that is in contact with 33
Via the valve seat 28
Sitting on the valve to close the valve opening 7, and the plunger 36 is also pushed down to the pilot port 24 side by the sum of the elastic force F2 of the main spring 37 and the pressing force due to the pressure receiving area difference of the plunger 36. The valve body 38 of the jar 36 is seated on the pilot port 24 to close the valve, so that the fluid flowing from the inlet 3 flows into the pilot chamber 31 through the bleed port 32 of the differential pressure sensing body 23. The pressure of the chamber 2 and the pressure of the pilot chamber 31 become the same pressure, and the differential pressure receiving body 23 is caused by the difference between the pressure receiving area on the primary pressure chamber 2 side of the differential pressure receiving body 23 and the pressure receiving area on the pilot chamber 31 side. A force that pushes the valve opening 7 side (downward) is applied, and the diaphragm 26 of the differential pressure sensing body 23 keeps the valve opening 7 closed.

Next, when the coil 16 is energized, the coil 16 is energized.
The core 33 is magnetized by the electromagnetic force generated at, and the plunger 36 is pulled up and attracted by the core 33 in the direction (upward) away from the pilot port 24, and the pilot port 24 opens. And pilot room
The fluid 31 flows out into the secondary side pressure chamber 4, and as a result, the differential pressure sensing body 23 is pushed up, the diaphragm 26 separates from the valve seat 28, and the valve port 7 opens.

In this state, until the plunger 36 is attracted to the core 33, the core 33 is in a neutral state with respect to the electromagnetic force of the coil 16, and then the plunger 36 is attracted to the core 33. The pushing force F3 that pushes up the differential pressure receiving body 23 generated by the differential pressure between the primary pressure chamber 2 and the pilot chamber 31 due to the opening of the pilot port 24 is applied to the guide tubular portion 29.
To the core 33 via the
The core 33 moves upward in association with the differential pressure sensitive body 23 against the elastic force F1 of 35.

Regarding the amount of electricity (electromagnetic force) applied to the coil 16, the elastic force F2 of the main spring 37 and the plunger 36 are used.
The plunger 36 is attracted to the core 33 if the energization amount is larger than the sum of the pressing force due to the pressure receiving area difference.

[0036]

In summary, according to the present invention, the valve box 9 having the valve port 7 for communicating the fluid inlet 3 and the fluid outlet 5 and the valve seat 28 of the valve port 7 are provided in the valve box 9 so as to be seated. Differential pressure sensor 23
On the central axis of the coil 16, the core 33 neutrally held by the electromagnetic force of the coil 16, the secondary pressure chamber 4 and the pilot chamber provided in the differential pressure sensing body 23 by the electromagnetic force of the coil 16 And a plunger 36 that moves in a direction away from the pilot port 24 that communicates 31 with each other. The valve box 9 or the differential pressure sensing body 23 is provided with a bleed port 32 that communicates the primary pressure chamber 2 and the pilot chamber 31 with each other. A guide tube portion 29 is provided so as to project from the outer side of the pilot port 24 of the differential pressure receiving body 23, the lower end of the core 33 is brought into contact with the upper end of the guide tube portion 29, and the core 33 is applied with a predetermined elastic force F1. Is provided with an auxiliary spring 35 for urging the differential pressure receiving body 23 toward the differential pressure receiving body 23, and the plunger 36 is arranged in the guide tube portion 29, and the plunger 16 has an elastic force F2 smaller than the electromagnetic force of the coil 16. 36 pilot port
Since the main spring 37 that urges to the 24 side is provided, when the coil 16 is energized, the core 33 is magnetized and the plunger 36
Is adsorbed to the core 33, the pilot port 24 is opened, and the differential pressure sensing body 23 is pushed up, so that the valve port 7 can be opened.

In this valve opening state, the core 33 is in a neutral state with respect to the electromagnetic force of the coil 16 until the plunger 36 is attracted to the core 33, and then the plunger 36 is moved to the core 33. And a push-up force F3 that pushes up the differential pressure sensing body 23 generated by the differential pressure between the primary pressure chamber 2 and the pilot chamber 31 due to the opening of the pilot port 24 is applied to the core 33 via the guide tube portion 29, As a result, the core 33 moves upward in association with the elastic force F1 of the auxiliary spring 35 in conjunction with the differential pressure sensitive body 23, so that the plunger d can be moved directly by the electromagnetic force of the conventional coil c. Compared to the electromagnetic force, the force of push-up F3 of the differential pressure sensitive body causes the core
Since 33 is moved, the electromagnetic force need only be large enough to attract the plunger 36 to the core 33, and the electromagnetic force of the coil 16 can be significantly reduced. This is a great practical effect in that the size can be reduced, the collar f for increasing the magnetic efficiency as in the conventional case is not required, the structure can be simplified, and the cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a solenoid valve according to the present invention in operation and in non-operation.

FIG. 2 is a cross-sectional view showing a solenoid valve according to another embodiment of the present invention when the solenoid valve is operating and not operating.

FIG. 3 is a cross-sectional view showing a conventional pilot type solenoid valve in operation and in non-operation.

[Explanation of symbols]

 2 Primary pressure chamber 3 Inlet 4 Secondary pressure chamber 5 Outlet 7 Valve port 9 Valve box 16 Coil 17 Yoke 19 Upper wall 20 Lower wall 23 Differential pressure sensor 24 Pilot port 28 Valve seat 29 Guide cylinder 31 Pilot Chamber 32 Bleed port 33 Core 35 Auxiliary spring 36 Plunger 37 Main spring

Claims (1)

[Claims] 1. A valve box having a valve port communicating an inlet and an outlet of a fluid, a differential pressure sensing member provided in the valve box so as to be seated on a valve seat of the valve port, and on a central axis of a coil. And a plunger that is neutrally held by the electromagnetic force of the coil, and a plunger that moves in a direction away from a pilot port that communicates the secondary pressure chamber and the pilot chamber provided in the differential pressure sensitive body with the electromagnetic force of the coil. The valve box or the differential pressure receiving body is provided with a bleed port that connects the primary side pressure chamber and the pilot chamber, and the guide cylinder portion is projected from the outside of the pilot port of the differential pressure receiving body. The lower end of the core is brought into contact with the upper end of the tubular part, and an auxiliary spring for urging the core toward the differential pressure receiving body by a predetermined elastic force is provided. Smaller than the electromagnetic force of A solenoid valve that is equipped with a main spring that urges the plunger toward the pilot port with force.