KR20010093116A - Constant pressure regulator - Google Patents

Abstract

The present invention provides a high precision static pressure regulator that can be used in a highly corrosive and dust free chemical line.

A main body 1 having a first valve chamber 9 and a liquid inlet 7, a cover 2 having a second valve chamber 10 and a fluid outlet 8, and an upper peripheral edge of the first valve chamber. And a shaft joined to the first diaphragm 3 fixed to the second diaphragm 4 held by the main body and the cover, and to the annular joints 15 and 16 provided in the center of the first and second diaphragms. Fluid control between the sleeve 5 movable in the direction, the sleeve 5 fixed to the bottom of the first valve chamber and axially movable, and the bottom end of the sleeve fixed to the bottom of the first valve chamber. And an air supply port 12 communicating with the air chamber, having an air chamber 11 surrounded by the inner circumferential surface of the main body and the first and second diaphragms. The hydraulic pressure area of the 2 diaphragms 4 becomes larger than the hydraulic pressure area of the 1st diaphragm 3.

Description

Constant pressure regulator

A conventional positive pressure regulator is generally shown in FIG. In FIG. 5, reference numeral 30 denotes a main body, and a first valve chamber 35 is installed at a lower portion thereof, and a fluid inlet 37 and a second valve chamber 36 communicating with the first valve chamber 35 at a side surface thereof. The fluid outlet 38 which communicated is provided. The upper part of the main body 30 forms the 2nd valve chamber 36 with the diaphragm 32. As shown in FIG. Reference numeral 31 denotes a cover, which forms an air chamber 39 together with the diaphragm 32, and has an air port 42 in communication with the air chamber 39 thereon. In addition, a constant air pressure is always applied to the air chamber 39. The rod 33 is provided in the center of the diaphragm 32, and the plug 34 larger than the diameter of the flow path 41 of the main body 30 is provided in the front-end | tip of the said rod 33. As shown in FIG.

In such a static pressure regulator, the fluid pressure of the second valve chamber 36 is maintained to be almost equal to the pressure applied to the air chamber 39 by balancing 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 diaphragm 32 is pushed upward because the fluid pressure side becomes larger than the pressure in the air chamber 39. At this time, the rod 33 and the plug 34 attached to the diaphragm 32 also move upward with the diaphragm, and the opening area of the control portion 40 formed between the plug 34 and the main body is reduced. As a result, the pressure loss of the fluid passing through the control unit 40 increases, and in the second valve chamber 36, the secondary pressure decreases to a pressure substantially equal to 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, the opening area of the controller 40 is reversed. Is increased, the pressure loss of the fluid is reduced, and the fluid pressure in the second valve chamber again rises to almost the same pressure as the pressure in the air chamber. As described above, in the conventional positive pressure regulator, the secondary pressure is kept constant even if the primary pressure fluctuates.

However, in the conventional static pressure regulator, since the rod penetrates the flow path, when the primary fluid pressure fluctuates frequently or when the pressure fluctuation is large, the rod is inclined and the pressure control becomes unstable. In addition, there was a problem that wear and dust are generated by contact between the rod and the main body. In addition, in order to cope with the small flow rate, it is necessary to reduce the diameter of the flow path. However, in such a structure, when the diameter of the flow path is reduced, the diameter of the rod must be thinner, and the problem of insufficient strength of the rod and difficulty in processing and assembling are also required. there was.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static pressure regulator that maintains a constant fluid pressure on the secondary side (downstream side) even when the liquid pressure on the primary side (upstream side) fluctuates, particularly in ultrapure water lines and various chemical lines. The present invention relates to a constant pressure regulator in which compact and stable pressure control, which is suitably used, is obtained and dust is less generated.

1 is a longitudinal cross-sectional view of a static pressure regulator of the present invention.

FIG. 2 is a longitudinal sectional view showing a state in which the primary pressure rises in FIG. 1.

3 is a longitudinal cross-sectional view showing a second embodiment in which both the first and second diaphragms, the sleeve, and the main body are formed integrally.

4 is a longitudinal cross-sectional view showing a third embodiment in which an orifice portion is provided between the second valve chamber and the fluid outlet port communicating with it.

5 is a longitudinal sectional view of a conventional positive pressure regulator.

6 is a graph showing the characteristics of the static pressure regulator of the present invention.

The present invention has been made in view of the problems of the conventional positive pressure regulator, and an object thereof is to provide a compact and very precise positive pressure regulator which can be used in a highly corrosive chemical liquid line or a chemical liquid line which does not generate dust.

In order to achieve the above object, the configuration of the present invention comprises: a cylindrical body having a first valve chamber, a stepped portion provided at an upper portion of the first valve chamber, and a fluid inlet port communicating with the first valve chamber; A cover joined to the upper portion of the body and having a fluid outlet communicating with the second valve chamber and the second valve chamber; A first diaphragm in which an annular protrusion provided on a peripheral edge is joined to a joint provided on an upper peripheral edge of the first valve chamber; A second diaphragm in which the annular protrusion provided on the peripheral edge is sandwiched by the body and the cover; A sleeve joined to an annular joint provided in the center of the first and second diaphragms and axially movable; It is composed of a plug fixed to the bottom of the first valve chamber and forming a fluid control portion between the lower end of the sleeve, and also has an inner circumferential surface of the step portion of the body and an air chamber surrounded by the first and second diaphragms. The pressure receiving area of the second diaphragm is larger than the pressure receiving area of the first diaphragm, and an air supply port communicating with the air chamber is provided in the main body.

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

Also, the diaphragm is usually made of polytetrafluoroethylene.

Furthermore, an orifice portion is provided between the second chamber chamber and the fluid outlet port communicating with it.

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

1 is a longitudinal cross-sectional view of a static pressure regulator of the present invention. Fig. 2 is a longitudinal sectional view showing a state in which the primary pressure rises in the positive pressure regulator of the present invention.

In the drawing, reference numeral 1 denotes a cylindrical main body, and an air supply in communication with the fluid inlet 7 and the air chamber 11 communicating with the first valve chamber 9 provided inside the main body 1 on the side. The port 12 is provided, and has a joint (annular cutout) 13 to which the annular projection 17 of the first diaphragm 3 is joined to the upper peripheral edge of the first valve chamber 9. Moreover, the step part 21 which forms the air chamber 11 with the 1st diaphragm 3 and the 2nd diaphragm 4 is provided in the upper part of the 1st valve chamber 9. In addition, the step portion 21 need not necessarily be integrally formed with the main body 1, and may be formed as a separate member having an annular shape.

Reference numeral 2 is a cover, has a second valve chamber 10 therein and an outlet 8 communicating with the second valve chamber 10 on the outer circumferential side thereof, and has a bolt or the like at the upper end of the main body 1. Not bonded). An annular groove portion 14, into which the annular projection 18 of the second diaphragm 4 is fitted, is provided in the peripheral edge portion of the second valve chamber 10 of the lower end of the cover 2.

The first diaphragm 3 is made of polytetrafluoroethylene (PTFE) and formed in a doughnut shape, and an annular junction 15 is provided at the center portion, and an annular protrusion 17 having a rectangular cross section at the outer peripheral portion thereof. It is installed. The cylindrical sleeve 5 is helically attached to the inner circumferential surface of the annular junction 15 of the first diaphragm 3, while the annular projection 17 is joined to the junction 13 provided inside the main body 1. It is.

The second diaphragm 4 is also made of PTFE, and similarly to the first diaphragm 3, an annular joint 16 is provided in the center portion, and an annular protrusion 18 in the shape of a cross section is provided at the outer peripheral edge thereof. The annular projection 18 is fitted by the annular groove 14 of the cover 2 and is held by the main body 1 and the cover 2 by joining the cover 2 to the upper end surface of the main body 1. . In addition, the hydraulic pressure area of the second diaphragm 4 is designed to be sufficiently larger than the first diaphragm 3.

The outer circumferential surface of the cylindrical sleeve 5 is provided with a helical coupling portion 19, wherein the helical coupling portion 19 is screwed with the annular joints 15, 16 of the first and second diaphragms 3, 4. By being combined, both diaphragms are integrated and remain movable in the axial direction. In addition, the inside of the sleeve 5 is a fluid flow path.

Reference numeral 6 is a plug, and is fixed to the bottom of the first valve chamber 9 by screwing or the like. The tip of the plug 6 forms the fluid control part 20 between the lower end surface of the sleeve 5, and the opening area of the fluid control part 20 changes with the vertical movement of the sleeve 5, The pressure inside the second valve chamber 10, that is, the secondary pressure, is designed to be kept constant.

The air chamber 11 is formed by enclosing the stepped portion 21 of the main body 1 and the three characters of the first and second diaphragms 3 and 4. Compressed air, an inert gas, or the like is introduced into the air chamber 11 from the air supply port 12, and is always maintained at a constant pressure.

As can be seen from the above description, the first and second diaphragms 3 and 4 integrated into the sleeve 5 have a stepped portion 21 provided in the main body 1 and a second valve chamber 10 provided in the cover 2. It is arrange | positioned in the space enclosed by), and it has a structure in which the air chamber 11 was formed by it.

In addition, although the fluororesins, such as PTFE and PFA, are normally used for materials, such as a main body, other plastics, such as polyvinyl chloride and polypropylene, or a metal may be sufficient, and are not specifically limited. In addition, although the fluororesin, such as PTFE, is used normally as a material of a 1st and 2nd diaphragm, rubber and a metal may be sufficient, and are not specifically limited.

Next, the operation of the static pressure regulator of the present embodiment will be described.

In the state of FIG. 1, the first diaphragm 3 receives an upward force due to the pressure inside the first valve chamber 9, that is, a primary pressure, and a downward force due to the pressure inside the air chamber 11. On the other hand, the second diaphragm 4 receives the downward force due to the pressure inside the second valve chamber 10, that is, the secondary pressure, and the upward force due to the pressure inside the air chamber 11, and these four forces The position of the sleeve 5 joined to the first and second diaphragms 3 and 4 is determined by the balancing of. The sleeve 5 forms the fluid control part 20 between the plug 6, and controls the fluid pressure of a secondary side by the area.

When the pressure on the primary side rises in this state, the pressure and flow rate on the secondary side also temporarily increase. 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 hydraulic pressure area of the third diaphragm 4 is the first diaphragm 3. Since it is designed sufficiently large as compared with, the downward force becomes larger, and as a result, the sleeve 5 is pushed downward (state of FIG. 2). For this reason, the opening area of the fluid control unit 20 decreases, the fluid pressure on the secondary side drops to the original pressure in an instant, and the balance between the internal pressure of the air chamber 11 and the force by the fluid pressure is maintained again. Usually, the fixed throttle part or valve which is not shown in figure is provided downstream of the static pressure regulator of this invention. When the downstream side of the fixed throttle or the valve is opened to the atmosphere, the pressure difference before and after the fixed throttle or the valve is always kept constant, and the flow rate corresponding to the flow coefficient of the fixed throttle or the valve is always maintained.

On the other hand, when 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, the first and second diaphragms 3 and 4 are forced downward and upward by the internal pressure of the air chamber 11, but in this case, the hydraulic pressure area of the second diaphragm 4 Since the upward force is large, the position of the sleeve 5 is pushed upward. For this reason, the opening area of the fluid control part 20 increases (the state of FIG. 1), and the fluid pressure of a secondary side rises to the original pressure in an instant, and the force by the internal pressure and the fluid pressure of the air chamber 11 is again raised. Equilibrium is maintained and the original flow rate is also maintained.

Even if the primary pressure increases or decreases as described above, the position of the sleeve 5 changes instantly, and the secondary pressure is kept constant at all times, so that the set flow rate can be obtained.

In addition, when the internal pressure of the air chamber 11 is changed, the secondary pressure is maintained at a value corresponding thereto, so that the set flow rate can be changed if there is no change in the fixed throttle part or the valve provided on the downstream side.

Next, the characteristic of the static pressure regulator in this invention is demonstrated.

Fig. 6 shows the result of measuring how the secondary side pressure changes when a fixed throttle (orifice diameter 2 mm) is provided downstream of the static pressure regulator of the present invention and the primary side pressure of the regulator is changed. The figure shows the case where the pressure in the air chamber is set to 0.04 MPa and 0.08 MPa, respectively, in solid and dashed lines. In either case, even if the primary pressure rises, the secondary pressure is substantially the same as the pressure in the air chamber and is constant.

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, the sleeve, and the main body are integrally formed. Here, the step portion 21 of the main body forming the air chamber is a separate part from the main body. Since the operation of the valve is the same as described above, the description thereof is omitted.

4 is a longitudinal sectional view showing a third embodiment of the present invention. The difference from the first embodiment is that the orifice portion 22 is provided between the second valve chamber 10 and the fluid outlet port 8 in communication therewith. When the downstream side of the orifice portion 22 is kept open to the atmosphere, even if the pressure on the primary side fluctuates, the pressure difference before and after the orifice portion always remains constant, so that the flow rate passing through the orifice portion 22 becomes constant, It can be used as a valve. Since the operation of the valve is the same as described above, the description is omitted.

The static pressure regulator of the present invention has the structure described above, and the following excellent effects are obtained by using this.

(1) Since there is no rod part as in the prior art, there is no control failure due to the inclination of the rod during operation, and stable pressure control is obtained.

(2) Since all the members which come into contact with the liquid can be made of a material having excellent chemical resistance such as PTFE, in this case, the elution of impurities and the contamination of the chemical liquid are extremely small.

(3) Since there is no rod part, there is no abrasion and dust generation, and even a compact product can obtain sufficient part strength, so that it can cope with a small flow rate and can be easily processed and assembled.

Claims (4)

A cylindrical body having a first valve chamber therein, a stepped portion provided at an upper portion of the first valve chamber, and a fluid inlet port communicating with the first valve chamber; A cover joined to the upper portion of the body and having a second valve chamber and a fluid outlet communicating with the second valve chamber; A first diaphragm in which an annular protrusion provided on a peripheral edge is joined to a joint provided on an upper peripheral edge of the first valve chamber; A second diaphragm in which the annular protrusion provided on the peripheral edge is sandwiched by the body and the cover; A sleeve joined to an annular joint provided in the center of the first and second diaphragms and axially movable; A plug fixed to the bottom of the first valve chamber and forming a fluid control portion between the lower end of the sleeve, Having an inner circumferential surface of the step portion of the main body and an air chamber surrounded by the first and second diaphragms, And a pressure supply area of the second diaphragm is larger than that of the first diaphragm, and an air supply port communicating with the air chamber is provided in the main body. The static pressure regulator according to claim 1, wherein the first and second diaphragms, the sleeve, and the main body are integrally formed. The static pressure regulator according to claim 1 or 2, wherein the diaphragm is made of polytetrafluoroethylene. The static pressure regulator according to claim 1 or 2, wherein an orifice portion is provided between the second valve chamber and the fluid outlet port communicating with the second valve chamber.