JP3737050B2 - Constant pressure regulator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a constant pressure regulator that keeps the fluid pressure on the secondary side (downstream side) constant even if the fluid pressure on the primary side (upstream side) fluctuates. More specifically, the present invention mainly relates to various chemical liquid lines such as chemical plants. The present invention relates to a constant pressure regulator that can be suitably used to obtain a compact and stable fluid pressure control.
[0002]
[Prior art]
The present inventors have previously filed an application for a constant pressure regulator that has solved dust generation due to contact of components inside the constant pressure regulator, deterioration of pressure control performance at a minute flow rate, and the like. No. 141083.
[0003]
As shown in FIG. 7, the structure includes a main body 42 having a first valve chamber 40 and an inlet channel 41, a lid 45 having a second valve chamber 43 and an outlet channel 44, and an upper peripheral edge of the first valve chamber 40. Joined to the first diaphragm 46 fixed to the second diaphragm 47, the second diaphragm 47 sandwiched between the main body 42 and the lid body 45, and the annular joints 48, 48 'provided at the center of the first and second diaphragms 46, 47. A diaphragm 50 comprising an axially movable sleeve 49 and a plug 52 fixed to the bottom of the first valve chamber 40 and forming a fluid control part 51 between the lower end of the sleeve 49, 42 has an air chamber 53 surrounded by an inner circumferential surface of the diaphragm 42 and the diaphragm 50, an air supply port 54 communicating with the air chamber 53 is provided, and the pressure receiving area of the second diaphragm 47 is larger than the pressure receiving area of the first diaphragm 46. Large And it has a structure.
[0004]
The conventional constant pressure regulator having the above configuration is used by introducing compressed air or inert gas into the air chamber 53, and the operation is as follows.
[0005]
The diaphragm 50 receives a primary fluid pressure on the lower surface of the first diaphragm 46, a secondary fluid pressure on the upper surface of the second diaphragm 47, and further in the air chamber 53 on the upper surface of the first diaphragm 46 and the lower surface of the second diaphragm 47. Under the pressure of air or inert gas. Therefore, a downward force due to the secondary fluid pressure, an upward force due to the primary fluid pressure, and an upward and downward force due to the pressure in the air chamber 53 act on the diaphragm 50, and the sleeve 49 of the diaphragm 50 It is stable at a position where two forces are balanced.
[0006]
Here, for example, when the primary side fluid pressure increases, the secondary side fluid pressure also instantaneously increases, and the force received from the fluid in both the first diaphragm 46 and the second diaphragm 47 increases. At this time, the pressure in the air chamber 53 is unchanged, and further, the pressure receiving area of the second diaphragm 47 is designed to be larger than that of the first diaphragm 46, so that the force to push down the diaphragm 50 becomes dominant, and the diaphragm 50 The sleeve 49 moves downward. Therefore, the opening area of the fluid control unit 51 decreases, and the fluid pressure on the secondary side also decreases until the four forces are balanced.
[0007]
Conversely, when the primary fluid pressure decreases, the secondary fluid pressure also decreases at the same time. However, since the pressure in the air chamber 53 is unchanged, the force that pushes up the diaphragm 50 becomes dominant, the sleeve 49 of the diaphragm 50 moves upward, and the opening area of the fluid control unit 51 increases. Accordingly, the fluid pressure on the secondary side also increases until the four forces are balanced.
[0008]
As described above, even if the fluid pressure on the primary side increases or decreases, the position of the sleeve 49 of the diaphragm 50 changes instantaneously so that the pressure on the secondary side is always kept substantially equal to the pressure in the air chamber 53. It has become.
[0009]
[Problems to be solved by the invention]
However, the constant pressure regulator has been developed as suitable for a line having a low fluid pressure, and has the following problems when used in a line having a high fluid pressure.
[0010]
In the line with high fluid pressure, the fluid pressure on the secondary side is naturally high, and the pressure in the air chamber 53 is set high so as to balance it. In this state, when the primary side fluid pressure is lower than the pressure in the air chamber 53 by closing the valve provided on the primary side or stopping the pressurizing pump, the four forces acting on the diaphragm 50 are applied. Cannot be balanced, and the diaphragm 50 is always pushed upward by compressed air or inert gas in the air chamber 53. As a result, the diaphragm 50 may be stretched or damaged, and the pressure control performance may be deteriorated.
[0011]
Further, if the secondary side is completely shut off, such as by closing a valve provided on the secondary side, the fluid pressure on the secondary side inevitably increases to the same level as the fluid pressure on the primary side, and the pressure in the air chamber 53 is increased. Bigger than. Therefore, the force received by the diaphragm 50 cannot be balanced, the diaphragm 50 is pushed down, and the sleeve 49 is pressed against the plug 52. As a result, the plug 52 is scratched or, if it is worse, buckling. Further, the sleeve 49 may be scratched, and the pressure control performance may be deteriorated due to the scratch or buckling.
[0012]
The present invention has been improved in view of the above-mentioned problems of the prior art, and can maintain the valve chamber sealing performance for a long period of time and can be used in a high-pressure liquid line, and is a compact and stable fluid pressure control. An object of the present invention is to provide a constant pressure regulator capable of obtaining the above.
[0013]
[Means for Solving the Problems]
The structure of the present invention will be described with reference to FIG. 1. The main body 1, the lid 2, the air chamber forming ring 3 sandwiched between the main body 1 and the lid 2, and the upper and lower portions are the lid 2 and the air chamber, respectively. A constant pressure regulator having a diaphragm 4 engaged with a forming ring 3 therein, the main body 1 has a cylindrical plug 6 located at the center and protruding from the center of the bottom surface. An inlet channel 8 communicating with the valve chamber 7 and the first valve chamber 7 is provided, and the diaphragm 4 has an inner diameter smaller than the outer diameter of the plug 6 that forms the fluid control unit 10 with the plug 6 at the center. A cylindrical portion 11 having a cylindrical portion 11, a flange portion 13 provided on the upper portion of the cylindrical portion 11, a first membrane portion 15 extending in the radial direction of the flange portion 13, and having an annular protrusion 14 on the peripheral edge thereof, and the cylindrical portion A second film portion 16 provided radially extending on the lower end surface of 11; An annular joint 17 is provided continuously to the bilayer membrane 16 and joined to the joint 24 of the air chamber forming ring 3, and the bottom surface of the annular joint 17 is sealed with the upper surface of the main body 1. The lid 2 is in contact with the annular groove 19 in which the annular protrusion 14 of the diaphragm 4 is fitted to the peripheral edge portion of the lower end surface, and is positioned inside the groove 19 to allow the diaphragm 4 to move up and down. A stopper 21 for defining the upper limit position of the diaphragm 4 provided so as to protrude from the upper surface of the valve chamber 20 and the second valve chamber 20 and an outlet channel 22 communicating with the second valve chamber 20 are provided. An air chamber forming ring 3 that is sandwiched between the lids 2 and forms an air chamber 5 with the diaphragm 4 includes a step portion 23 that encloses the flange portion 13 of the diaphragm 4 and an annular shape of the diaphragm 4 below the step portion 23. Continuous with the joint 24 where the joint 17 is joined In addition, a vent hole 25 is provided to communicate the air chamber 5 with the outside, and the lid 2 and the air chamber forming ring 3 are sealed on the outside of the step portion 23 of the air chamber forming ring 3. The first feature is that the main body 1 and the air chamber forming ring 3 are joined via a seal ring 9 outside the joining portion 24 of the ring 3.
[0014]
The second feature is that the outer diameter of the annular joint 17 of the diaphragm 4 is smaller than the outer diameter of the flange 13.
[0015]
A third feature is that an annular notch 27 is provided on the outer peripheral lower surface of the annular protrusion 14 of the diaphragm 4, and a seal ring 28 is fitted into the notch 27.
[0016]
A fourth feature is that at least two air holes 25 communicating the air chamber 5 and the outside are provided.
[0017]
A fifth feature is that the material of the diaphragm 4 is PTFE.
[0018]
The material of the main body 1 and the lid 2 is preferably a fluororesin such as PTFE or PFA, but may be other plastics or metals such as polyvinyl chloride or polypropylene, and is not particularly limited. In addition, polypropylene is preferably used for the air chamber forming ring 3 from the viewpoint of strength and heat resistance, but similarly, other plastics and metals may be used and are not particularly limited. Further, the material of the diaphragm 4 is preferably a fluororesin such as PTFE, but may be rubber or metal and is not particularly limited.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings, but it goes without saying that the present invention is not limited to the embodiments.
[0020]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the constant pressure regulator of the present invention. FIG. 2 is a longitudinal sectional view showing a state where the primary side pressure is lowered in the constant pressure regulator of the present invention. FIG. 3 is a longitudinal sectional view showing a state in which the primary side pressure is further lowered in the constant pressure regulator of the present invention from the state of FIG. FIG. 4 is a longitudinal sectional view showing a case where the secondary side pipe is blocked. FIG. 5 is a bottom view of the lid in FIG. FIG. 6 is a longitudinal sectional view showing a second embodiment of the constant pressure regulator of the present invention.
[0021]
In the figure, reference numeral 1 denotes a PTFE main body having a first valve chamber 7 inside, and an inlet channel 8 communicating with the first valve chamber 7 is provided on a side surface. Furthermore, the upper surface has a larger diameter than that of the first valve chamber 7 and an annular groove into which the annular protrusion 18 provided on the bottom surface of the annular joint 17 of the diaphragm 4 is fitted. An annular groove into which a seal ring 9 for sealing between the chamber forming ring 3 and the main body 1 is inserted is provided. A cylindrical plug 6 protrudes from the center of the bottom surface of the first valve chamber 7.
[0022]
Reference numeral 2 denotes a PTFE lid, which has an annular groove 19 in which the annular protrusion 14 of the diaphragm 4 is fitted at the peripheral edge of the lower end surface, and a transverse cross-sectional shape that is located inside the groove 19 and allows the diaphragm 4 to move up and down. A second valve chamber 20 having a circular shape and an outlet channel 22 communicating with the second valve chamber 20 are provided on the side surface. A stopper 21 having a C-shaped cross section protrudes from the upper surface of the second valve chamber 20. Since the shape of the stopper 21 is open to the second valve chamber 20, even when the diaphragm 4 comes into contact with the stopper 21, the stopper 21 flows from the fluid flow hole 12 of the diaphragm 4 to the second valve chamber 20 and the outlet channel 22. (See FIG. 5). In this embodiment, the stopper 21 is formed in a C-shaped cross section to prevent fluid retention, but may be one or more columns or cylinders as long as the fluid flow is not obstructed. Is not limited.
[0023]
The air chamber forming ring 3 is made of polypropylene, and is provided with a step portion 23 enclosing the flange portion 13 of the diaphragm 4 and a joint portion 24 where the annular joint portion 17 of the diaphragm 4 is joined to the lower portion thereof. Yes. Further, vent holes 25 and 26 for communicating the air chamber 5 with the outside and an annular groove into which a seal ring 28 for sealing the air chamber 5 between the lid body 2 is inserted are provided outside the step portion 23. It has been. In addition, although the ventilation hole is provided with two pieces 25 and 26 for intake and exhaust, one can be used and the number is not limited.
[0024]
The diaphragm 4 is made of PTFE, and has a cylindrical portion 11 having an inner diameter smaller than the outer diameter of the plug 6 of the main body 1 at the center, a flange portion 13 provided on the upper portion of the cylindrical portion 11, and a radial direction of the flange portion 13. A first film part 15 having an annular protrusion 14 on its peripheral edge, a second film part 16 provided radially extending on the lower end surface of the cylindrical part 11, and a second film An annular joint portion 17 that is provided continuously with the portion 16 and screwed into the joint portion 24 of the air chamber forming ring 3 is provided. On the bottom surface of the annular joint 17, an annular protrusion 18 is provided that fits into an annular groove provided on the outside of the first valve chamber 7 of the main body 1, whereby the diaphragm 4 and the main body 1 are interposed. Thus, the first valve chamber 7 and the air chamber 5 are sealed. However, an O-ring or a plastic seal ring may be used for sealing between the two, and the method is not limited. A fluid control unit 10 is formed between the lower end portion of the cylindrical portion 11 and the upper surface of the plug 6 provided in the central portion of the first valve chamber 7. The joining method of the annular joining portion 17 to the joining portion 24 of the air chamber forming ring 3 is not limited to screwing, and other joining methods may be used. The pressure receiving area on the upper surface of the diaphragm 4 must be larger than the pressure receiving area on the lower surface, that is, the pressure receiving area of the second film portion 16.
[0025]
The air chamber 5 is formed by being surrounded by a diaphragm 4 and an air chamber forming ring 3. Compressed air or inert gas whose pressure is adjusted using a gas regulator or the like is introduced into the air chamber 5 from the vent hole 25, and the air hole 5 is constant while being discharged in a minute amount. Adjusted to maintain pressure. In addition, if the air or gas pressure is changed, the secondary fluid pressure of the constant pressure regulator will be maintained at the corresponding value. Therefore, by adjusting the air or gas pressure, the secondary pressure of the regulator is desired. Adjustable to pressure.
[0026]
The operation of the constant pressure regulator of the present embodiment having the above-described configuration is as follows.
[0027]
In the state of FIG. 1, the second membrane portion 16 receives an upward force due to the pressure inside the first valve chamber 7, that is, the upstream (primary side) pressure, and a downward force due to the pressure inside the air chamber 5. On the other hand, the upper surface of the diaphragm 4 has a downward force due to the pressure inside the second valve chamber 20, that is, the downstream (secondary side) pressure, and the lower surfaces of the first film portion 15 and the flange portion 13 corresponding to the upper surface of the diaphragm 4. An upward force due to the pressure inside the air chamber 5 is received, and the position of the cylindrical portion 11 provided integrally with the diaphragm 4 is determined by the balance of these four forces.
[0028]
Now, when the pressure on the primary side decreases in the state of FIG. 1, the pressure on the secondary side temporarily drops. Therefore, the pressure in the second valve chamber 20 decreases, the pressure received by the upper surface of the diaphragm 4 also decreases, and the force received by the diaphragm 4 in the downward direction also decreases. On the other hand, since the internal pressure of the air chamber 5 received by the first film portion 15 and the flange portion 13 is not changed, the force acting upward on the diaphragm 4 does not change. Accordingly, the upward force acting on the diaphragm 4 is increased, and the cylindrical portion 11 is lifted upward. Further, since the pressure in the first valve chamber 7 is also reduced, the force received by the second membrane portion 16 from the fluid is reduced, but since the pressure in the air chamber 5 is unchanged, the second membrane portion 16 is a cylindrical portion. Try to pull 11 down. At this time, the areas of the first film part 15 and the collar part 13 are sufficiently larger than the area of the second film part 16, and as a result, the cylindrical part 11 is pulled upward (state of FIG. 3). As a result, the opening area of the fluid control unit 10 increases, the fluid pressure on the secondary side instantaneously increases to the original pressure, and the balance between the pressure inside the air chamber 5 and the force due to the fluid pressure is maintained again.
[0029]
On the other hand, when the pressure on the primary side increases in the state of FIG. 3, the pressure on the secondary side also temporarily increases. Therefore, the pressure in the second valve chamber 20 rises and tries to push down the cylindrical portion 11. Further, since the pressure in the first valve chamber 7 also increases, the second film portion 16 tends to push up the cylindrical portion 11. Similarly, since the area of the upper surface of the diaphragm 4 is sufficiently larger than the area of the second film part 16, the cylindrical part 11 is pushed down. As a result, the opening area of the fluid control unit 10 is reduced (the state shown in FIG. 1), the fluid pressure on the secondary side is instantaneously reduced to the original pressure, and the balance between the pressure inside the air chamber 5 and the force due to the fluid pressure is again obtained. Is preserved.
[0030]
As described above, even if the primary pressure increases or decreases, the position of the cylindrical portion 11 of the diaphragm 4 changes instantaneously, and the pressure inside the air chamber 5 and the pressure on the secondary side are always kept substantially equal.
[0031]
Here, when the primary side fluid pressure further decreases from the state of FIG. 2 and becomes lower than the pressure inside the air chamber 5, the secondary side fluid pressure naturally decreases to the same level as the primary side fluid pressure. Therefore, the force received by the upper surface of the diaphragm 4 is reduced. At this time, since the pressure in the air chamber 5 received by the first film portion 15 and the flange portion 13 corresponding to the diaphragm 4 is not changed, the diaphragm 4 is further pushed upward, and the opening area of the fluid control portion 10 is increased. However, since the fluid pressure on the primary side is low, the fluid pressure on the secondary side does not increase, and as a result, the diaphragm 4 is pushed up further, but the diaphragm 4 contacts the stopper 21 provided on the lid 2. By doing so, since the upper limit position of the diaphragm 4 is determined, it is prevented that the diaphragm 4 is pulled up more than necessary (state of FIG. 3). Therefore, the diaphragm 4 can be prevented from being stretched or damaged, and the pressure control performance can be prevented from deteriorating.
[0032]
Also, if the valve on the secondary side of the regulator is closed to shut off the secondary side flow path, the secondary pressure of the regulator will inevitably be equal to the primary side pressure. . At this time, if the fluid pressure on the primary side is higher than the pressure inside the air chamber 5, the fluid pressure on the secondary side naturally becomes higher than the pressure inside the air chamber 5. Since the area of the upper surface of the diaphragm 4 is larger than the areas of the first film portion 15 and the flange portion 13 corresponding thereto, the force that the upper surface of the diaphragm 4 receives downward from the fluid is upward from the air or inert gas inside the air chamber 5. Since the force is greater than the force received, a downward force always acts on the diaphragm 4. Therefore, the cylindrical portion 11 of the diaphragm 4 is pressed against the plug 6 of the main body 1, but the flange portion 13 of the diaphragm 4 contacts the stepped portion 23 of the air chamber forming ring 3 almost simultaneously with the contact of the cylindrical portion 11 and the plug 6. Since the lowering of the diaphragm 4 is prevented, the cylindrical portion 11 and the plug 6 are prevented from being pressed more than necessary (the state shown in FIG. 4). As a result, it is possible to prevent the plug 6 from being scratched or buckled and the cylindrical portion 11 from being scratched, thereby preventing the fluid pressure control performance from being deteriorated.
[0033]
FIG. 6 is a longitudinal sectional view showing a second embodiment of the present invention. The difference from the first embodiment is that an annular notch 27 is provided on the outer peripheral lower surface of the annular protrusion 14 of the diaphragm 4, and the annular notch 27 is provided between the main body 1 and the air chamber forming ring 3. The seal ring 28 for sealing is inserted. Since the operation of the valve is the same as described above, the description thereof is omitted.
[0034]
【The invention's effect】
The constant pressure regulator of the present invention has the structure as described above, and the following excellent effects can be obtained by using this regulator.
[0035]
(1) The upper limit position of the diaphragm is determined by the diaphragm coming into contact with the stopper provided on the lid, and the diaphragm is not lifted more than necessary. The diaphragm can be prevented from stretching or breaking.
[0036]
(2) Even if the fluid pressure on the secondary side of the constant pressure regulator rises excessively, the diaphragm flange and the step of the air chamber forming ring come into contact with each other to support the diaphragm, so that the cylindrical part of the diaphragm is required for the plug. Since it is no longer pressed, it is possible to prevent the plug from being scratched or buckled and the cylindrical portion from being scratched.
[0037]
(3) A compact structure and stable fluid pressure control can be obtained from a low pressure liquid line to a high pressure liquid line.
[0038]
(4) When a material excellent in chemical resistance such as PTFE is used for the member in contact with the liquid, since the elution of impurities and the contamination of the chemical liquid are extremely small, it is suitably used for a highly corrosive chemical liquid line.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of a constant pressure regulator of the present invention.
FIG. 2 is a longitudinal sectional view showing a state in which the primary side pressure is reduced in FIG.
3 is a longitudinal sectional view showing a state in which the primary pressure is further reduced in FIG.
4 is a longitudinal sectional view showing a state in which the secondary side pipe in FIG. 1 is completely shut off.
FIG. 5 is a bottom view of the lid.
FIG. 6 is a longitudinal sectional view showing a second embodiment of the constant pressure regulator of the present invention.
FIG. 7 is a longitudinal sectional view showing a conventional constant pressure regulator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Main body 2 ... Cover 3 ... Air chamber formation ring 4 ... Diaphragm 5 ... Air chamber 6 ... Plug 7 ... First valve chamber 8 ... Inlet channel 9 ... Seal ring 10 ... Fluid control part 11 ... Cylindrical part 12 ... Fluid flow hole 13 ... collar 14 ... annular protrusion 15 ... first film part 16 ... second film part 17 ... annular joint 18 ... annular protrusion 19 ... annular groove 20 ... second valve chamber 21 ... stopper 22 ... outlet Channel 23 ... Step 24 ... Joint portion 25 ... Vent hole 26 ... Vent hole 27 ... annular notch 28 ... Seal ring

Claims (5)

The main body (1), the lid (2), the air chamber forming ring (3) sandwiched between the main body (1) and the lid (2), and the upper and lower portions are the lid (2) and the air chamber forming respectively. A constant pressure regulator having a diaphragm (4) engaged with a ring (3) for use inside, a cylindrical plug provided at the center of the main body (1) and protruding from the center of the bottom surface A first valve chamber (7) having (6) and an inlet channel (8) communicating with the first valve chamber (7), and the diaphragm (4) has the plug (6) The cylindrical portion (11) having an inner diameter smaller than the outer diameter of the plug (6) forming the fluid control portion (10), and the flange portion (13) and the flange portion (13) provided on the upper portion of the cylindrical portion (11). ) And a cylindrical portion (1) and a cylindrical portion (1) having a ring-shaped protrusion (14) at the peripheral edge thereof. ) And a second membrane portion (16) provided radially extending on the lower end surface of the second membrane portion (16) and a joint portion (24) of the air chamber forming ring (3). And the bottom surface of the annular joint (17) is in sealing contact with the upper surface of the main body (1), and the lid (2) has a lower end surface. An annular groove (19) in which the annular protrusion (14) of the diaphragm (4) is fitted to the peripheral edge, and a second valve chamber (inside the groove (19)) that allows the diaphragm (4) to move up and down ( 20) and a stopper (21) that protrudes from the upper surface of the second valve chamber (20) and defines the upper limit position of the diaphragm (4), and an outlet channel (22) that communicates with the second valve chamber (20). Provided, and sandwiched between the main body (1) and the lid (2) to form an air chamber (5) between the diaphragm (4) In the air chamber forming ring (3), a step portion (23) containing the flange (13) of the diaphragm (4) and an annular joint portion (17) of the diaphragm (4) are joined to the lower portion (23). And a vent hole (25) for communicating the air chamber (5) with the outside, and a lid (2) and an air chamber forming ring (3). ) Is joined to the outside of the step portion (23) of the air chamber forming ring (3) via the seal ring (28), and the main body (1) and the air chamber forming ring (3) are connected to the ring (3). The constant pressure regulator characterized by being joined via the seal ring (9) in the outer side of a junction part (24). The constant pressure regulator according to claim 1, characterized in that the outer diameter of the annular joint (17) of the diaphragm (4) is smaller than the outer diameter of the flange (13). An annular notch (27) is provided on the outer peripheral lower surface of the annular protrusion (14) of the diaphragm (4), and a seal ring (28) is fitted into the notch (27). The constant pressure regulator according to claim 1. The constant pressure regulator according to any one of claims 1 to 3, wherein at least two vent holes (25) are provided. The constant pressure regulator according to any one of claims 1 to 4, wherein the material of the diaphragm (4) is polytetrafluoroethylene.

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