WO2001036851A1

WO2001036851A1 - Constant pressure regulator

Info

Publication number: WO2001036851A1
Application number: PCT/JP2000/007971
Authority: WO
Inventors: Toshihiro Hanada; Kenro Yoshino
Original assignee: Asahi Organic Chemicals Industry Co., Ltd.
Priority date: 1999-11-18
Filing date: 2000-11-10
Publication date: 2001-05-25
Also published as: KR20010093116A; JP2001141083A; TW464739B; JP3734394B2; KR100430169B1

Abstract

A constant pressure regulator with high accuracy capable of being used in a highly corrosive and dust-phobic liquid chemical line, comprising a main body (1) having a first valve chamber (9) and a fluid flow inlet (7), a cover body (2) having a second valve chamber (10) and a fluid flow outlet (8), a first diaphragm (3) fixed to the upper peripheral edge of the first valve chamber, a second diaphragm (4) held by and between the main body and the cover, a sleeve (5) connected to annular connection parts (15) and (16) provided at the centers of the first and second diaphragms and movable in axial direction, and a plug (6) fixed to the bottom part of the first valve chamber and forming a fluid control part (20) between the plug and a lower end part of the sleeve, wherein an air chamber (11) is provided which is surrounded by the inner peripheral surface of the main body and first and second diaphragms, an air feed port (12) communicating with the air chamber is provided, and the pressure receiving area of the second diaphragm (4) is larger than that of the first diaphragm (3).

Description

Description Constant pressure regulator Technical field

The present invention relates to a constant-pressure regulator that maintains a constant fluid pressure on the secondary side (downstream side) even when the fluid pressure on the primary side (upstream side) fluctuates. The present invention relates to a constant pressure regulator capable of obtaining stable pressure control with a compact suitably used for a water line or various chemical liquid lines and generating less dust. Background art

Conventional constant-pressure regulators are generally as shown in Fig. 5. In the figure, reference numeral 30 denotes a main body, and a lower portion is provided with a first valve chamber 35, and a fluid inlet 37 communicating with the first valve chamber 35 and a fluid communicating with the second valve chamber 36 on the side surface. An outlet 38 is provided. The upper part of the main body 30 forms a second valve chamber 36 together with the diaphragm 32. Numeral 31 denotes a lid, which forms an air chamber 39 with the diaphragm 32, and has an air port 42 communicating with the air chamber 39 at the upper part. Note that a constant air pressure is always applied to the air chamber 39. A port 33 is attached to the center of the diaphragm 32, and a plug 34 having a diameter larger than the diameter of the flow path 41 of the main body 30 is attached to the tip of the rod 33. I have.

In such a constant-pressure regulator, the fluid pressure in the second valve chamber 36 is kept substantially the same as the pressure applied to the air chamber 39 by the balance of the force applied to the diaphragm 32. When the fluid pressure on the primary side increases, the pressure on the secondary side also increases, and the fluid pressure becomes larger than the pressure in the air chamber 39, so that the diaphragm 32 is pushed upward. At this time The port 33 and the plug 34 attached to the diaphragm 32 also move upward with this, and the opening area of the control section 40 formed between the plug 34 and the main body is small. In other words, the pressure loss of the fluid passing through the control unit 40 increases, and the secondary pressure in the second valve chamber 36 drops again to substantially the same pressure as the pressure in the air chamber. On the other hand, when the pressure on the primary side decreases, the pressure in the air chamber becomes larger than the fluid pressure, so that the diaphragm 32 is pushed downward, and conversely to the above-described case, As the opening area increases, the pressure loss of the fluid decreases, and the fluid pressure in the second valve chamber rises again to almost the same pressure as the pressure in the air chamber. As described above, in the conventional constant-pressure regulator, the secondary pressure is kept constant even if the primary pressure fluctuates.

However, in the above-mentioned conventional constant-pressure regulator, the rod penetrates the inside of the flow path, so if the fluid pressure on the primary side fluctuates frequently or if the pressure fluctuates greatly, b. There were problems that the pressure was unstable due to the tilting of the rod and that the rod and the body contacted each other, causing wear and dust. Also, in order to cope with very small flow rates, it is necessary to reduce the diameter of the flow path, but in such a structure, if the diameter of the flow path is reduced, the diameter of the rod must also be reduced. However, there were also problems such as insufficient strength of the rod and difficulty in processing and assembling. Disclosure of the invention

The present invention has been made in view of the above-described problems of the conventional constant-pressure regulator, and therefore provides a compact and high-precision constant-pressure regulator that can be used even in a highly corrosive chemical liquid line or a chemical liquid line that dislikes dust generation. It is intended to provide.

In order to achieve the above object, the configuration of the present invention comprises a first valve chamber, a step provided above the first valve chamber, and a flow communicating with the first valve chamber. A cylindrical body having a body flow inlet, a lid body having a second valve chamber and a body flow outlet communicating therewith and joined to an upper part of the body, and an annular protrusion provided on a peripheral edge portion are provided as first parts. A first diaphragm joined to a joint provided on an upper peripheral edge of the valve chamber; a second diaphragm in which an annular projection provided on the peripheral edge is sandwiched between a main body and a lid; A sleeve joined to both annular joints provided at the center of the second diaphragm and movable in the axial direction; and a lower end fixed to the bottom of the first valve chamber. An air chamber surrounded by the inner peripheral surface of the step portion of the main body and the first and second diaphragms, and the second diaphragm Pressure receiving area of the first diaphragm is larger than the pressure receiving area of the first diaphragm. A communication port is provided in the main body for communication.

In a preferred embodiment of the present invention, the first and second diaphragms, sleeves and body are integrally formed.

Also preferably, the diaphragm is made of polytetrafluoroethylene.

Further, an orifice portion is provided between the second valve chamber and a fluid outlet communicating with the second valve chamber. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a longitudinal sectional view of the constant pressure regulator of the present invention.

FIG. 2 is a longitudinal sectional view showing a state in which the primary pressure is increased in FIG. 1. FIG. 3 is a second embodiment in which the first and second diaphragms, the sleeve and the main body are all integrally formed. FIG.

FIG. 4 is a longitudinal sectional view showing a third embodiment in which an orifice portion is provided between a second valve chamber and a fluid outlet communicating with the second valve chamber. FIG. 5 is a longitudinal sectional view of a conventional constant-pressure regulator.

FIG. 6 is a graph showing characteristics of the constant-pressure regulator according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a constant pressure regulator according to the present invention. FIG. 2 is a longitudinal sectional view showing a state where the primary pressure has increased in the constant-pressure regulator of the present invention.

In the figure, reference numeral 1 denotes a cylindrical main body, and a fluid supply port 7 communicating with a first valve chamber 9 provided inside the main body 1 and an air supply communicating with the air chamber 11 on the side surface. The first valve chamber 9 has a joining portion (annular notch) 13 to which the annular projection 17 of the first diaphragm 3 is joined. I have. Further, a step portion 21 that forms an air chamber 11 together with the first diaphragm 3 and the second diaphragm 4 is provided above the first valve chamber 9. Note that the step portion 21 does not necessarily need to be formed integrally with the main body 1, but may be formed by another annular part.

Reference numeral 2 denotes a lid, which has a second valve chamber 10 inside, an outlet 8 communicating with the second valve chamber 10 on the outer peripheral side surface, and a bolt or the like at the upper end of the main body 1. (Not shown). An annular groove 14 into which the annular protrusion 18 of the second diaphragm 4 is fitted is provided at the lower end of the lid 2 at the peripheral edge of the second valve chamber 10.

The first diaphragm 3 is made of tetrafluoroethylene (PTFE) and is formed in a donut shape. An annular joint 15 is provided at the center, and a rectangular cross section is formed at the outer peripheral edge. An annular projection 17 is provided. A cylindrical sleeve 5 is screwed onto the inner peripheral surface of the annular joint 15 of the first diaphragm 3, while the annular protrusion 17 is inside the main body 1. It is joined to the provided joint 13.

The second diaphragm 4 is also made of PTFE, and is provided with an annular joint 16 at the center and an annular protrusion 18 having a rectangular cross section at the outer peripheral edge, similarly to the first diaphragm 3. . The annular projection 18 is fitted into the annular groove 14 of the lid 2 and is sandwiched between the main body 1 and the lid 2 by joining the lid 2 to the upper end surface of the main body 1. . The pressure receiving area of the second diaphragm 4 is designed to be sufficiently larger than that of the first diaphragm 3.

A threaded portion 19 is provided on the outer peripheral surface of the cylindrical sleeve 5, and the threaded portion 19 is connected to the annular joint 15 of the first and second diaphragms 3, 4. The two diaphragms are integrated and held movably in the axial direction by being screwed to 16. The interior of the sleeve 5 is a fluid flow path.

Reference numeral 6 denotes a plug, which is fixed to the bottom of the first valve chamber 9 by screwing or the like. The tip of the plug 6 forms a fluid control unit 20 with the lower end surface of the sleeve 5, and the opening area of the fluid control unit 20 changes as the sleeve 5 moves up and down. It is designed to keep the pressure inside the second valve chamber 10, ie, the secondary pressure, constant.

The air chamber 11 is formed so as to be surrounded by a stepped portion 21 of the main body 1 and first and second diaphragms 3 and 4. Compressed air or an inert gas or the like is introduced into the air chamber 11 from the air supply port 12 and is always kept at a constant pressure.

As can be seen from the above description, the first and second diaphragms 3 and 4 integrated by the sleeve 5 have the stepped portion 21 provided on the main body 1 and the second The air chamber 11 is arranged in a space surrounded by the valve chamber 10 and the air chamber 11 is thereby formed.

Fluorine resin such as PTFE and PFA is preferably used for the material of the main body. The force to be used; other plastics such as polyvinyl chloride, polypropylene, etc. or metal may be used without any particular limitation. The material of the first and second diaphragms is not particularly limited, and may be a rubber or metal in which a fluororesin such as PTFE is suitably used.

Next, the operation of the constant pressure regulator of the present embodiment will be described. In the state shown in FIG. 1, the first diaphragm 3 receives an upward force due to the pressure inside the first valve chamber 9, that is, the primary pressure, and a downward force due to the pressure inside the air chamber 11. On the other hand, the second diaphragm 4 receives a downward force due to the pressure inside the second valve chamber 10, that is, the secondary pressure, and an upward force due to the pressure inside the air chamber 11, and the fishing of these four forces is performed. The position of the sleeve 5 joined to the first and second diaphragms 3 and 4 is determined by the engagement. The fluid control part 20 is formed between the sleeve 5 and the plug 6, and the area thereof controls the fluid pressure on the secondary side.

If the primary pressure increases in this state, the secondary pressure and flow rate also increase temporarily. At this time, an upward force acts on the first diaphragm 3 and a downward force acts on the second diaphragm 4 due to the fluid pressure, but the pressure receiving area of the second diaphragm 4 is larger than that of the first diaphragm 3. Designed to be large enough, the downward force will be greater, resulting in pushing down the sleeve 5 (as shown in Figure 2). As a result, the opening area of the fluid control unit 20 decreases, the fluid pressure on the secondary side instantaneously drops to the original pressure, and the balance between the internal pressure of the air chamber 11 and the fluid pressure is maintained again. It is. Usually, a fixed throttle or valve (not shown) is attached downstream of the constant pressure regulator of the present invention. If the downstream side of the fixed throttle or valve is open to the atmosphere, the differential pressure across the fixed throttle or valve will always be kept constant, and the flow rate corresponding to the flow coefficient of the fixed throttle or valve will always be maintained. Was It will be.

On the other hand, if the pressure on the primary side decreases in the state of Fig. 2, the pressure and flow rate on the secondary side also temporarily decrease. At this time, downward and upward forces act on the first and second diaphragms 3 and 4, respectively, due to the internal pressure of the air chamber 11, but even in this case, the pressure receiving area of the second diaphragm 4 is larger, so The upward force prevails and pushes the position of sleeve 5 upward. As a result, the opening area of the fluid control unit 20 increases (the state shown in FIG. 1), and the fluid pressure on the secondary side instantaneously rises to the original pressure, and again depends on the internal pressure of the air chamber 11 and the fluid pressure. Power balance is maintained and the original flow is maintained.

As described above, even if the primary pressure increases or decreases, the position of the sleeve 5 changes instantaneously, and the pressure on the secondary side is always kept constant, so that the set flow rate can be obtained.

If the internal pressure of the air chamber 11 is changed, the secondary pressure will be maintained at the corresponding value.If there is no change in the fixed throttle or valve installed downstream, the set flow rate should be changed. Can be.

Next, the characteristics of the constant pressure regulator according to the present invention will be described. Fig. 6 shows how the secondary pressure changes when a fixed throttle (orifice diameter 2 mm) is installed downstream of the constant pressure regulator of the present invention and the primary pressure of the regulator is changed. The result of the measurement is shown. In the figure, the solid line and the broken line show the case where the pressure in the air chamber is 0.04 MPa and 0.08 MPa, respectively. In both cases, even if the primary pressure rises, the secondary pressure remains almost the same as the pressure in the air chamber.

FIG. 3 is a longitudinal sectional view showing a second embodiment of the present invention. The difference from the first embodiment is that the first and second diaphragms, sleeve and main body are all integrally formed. Where the air chamber is formed The step 21 of the main body is a separate part from the main body. The operation of the valve is the same as described above, and a description thereof will be omitted.

FIG. 4 is a longitudinal sectional view showing a third embodiment of the present invention. The difference from the first embodiment is that an orifice portion 22 is provided between the second valve chamber 10 and the fluid outlet 8 communicating therewith. If the downstream side of the orifice section 22 is open to the atmosphere, the differential pressure across the orifice section is always kept constant even if the pressure on the primary side fluctuates. The flow rate through 22 becomes constant and can be used as a constant flow valve. The operation of the valve is the same as described above, and a description thereof will be omitted.

The constant-pressure regulator according to the present invention has the structure as described above, and the use of the constant-pressure regulator has the following excellent effects.

(1) Since there is no rod part unlike the conventional product, there is no control failure due to the inclination of the rod during operation, and stable pressure control can be obtained.

(2) Since all materials that come into contact with the liquid can be made of materials with excellent chemical resistance, such as PTFE, elution of impurities and contamination of the chemical solution are extremely small.

(3) Since there is no rod part, there is no abrasion or dust generation. Even with a compact product, sufficient component strength can be obtained, so that it can cope with minute flow rates and is easy to process and assemble.

Claims

The scope of the claims

1. A cylindrical body having a first valve chamber inside, a step provided above the first valve chamber, and a fluid inlet communicating with the first valve chamber, and a second valve chamber. A lid having a fluid outlet communicating therewith and joined to the upper part of the main body, and an annular projection provided on the peripheral part joined to a joint provided on the upper peripheral part of the first valve chamber. One diaphragm, a second diaphragm in which an annular protrusion provided on the peripheral edge is sandwiched between the main body and the lid, and two annular joints provided in the center of the first and second diaphragms. A sleeve fixed to the bottom of the first valve chamber and forming a fluid control unit between the sleeve and a lower end of the sleeve; An air chamber surrounded by the inner peripheral surface of the step portion of the main body and the first and second diaphragms; Arrow pressure receiving area of the ram is increased configured Ri by the pressure receiving area of the first diaphragms, pressure Regiyu regulator for the air supply port communicating with the air chamber, characterized in that you are provided on the main body.

2. The constant pressure regulator according to claim 1, wherein the first and second diaphragms, sleeves and main body are formed integrally.

3. The constant pressure regulator according to claim 1, wherein the diaphragm is made of polytetrafluoroethylene.

4. The constant pressure regulator according to claim 1, wherein an orifice portion is provided between the second valve chamber and a fluid outlet communicating with the second valve chamber. .