JP2007024069A - Air pressure type flow control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air pressure type flow control valve capable of realizing reproducibility of operation in opening and closing of a valve section by reducing a hysteresis error by reducing stress on a film of a diaphragm and improving response and stability of control, regarding the flow control valve specially used for semiconductor manufacturing or the like. <P>SOLUTION: The valve comprises a valve mechanism 30 having a valve section 35 sealing a valve seat 25, a first diaphragm 40 disposed at the first opening 21 side and a second diaphragm 50 disposed at the second opening 22 side, all provided integrally, and controls a flow rate by applying pressure to the first and second diaphragms 40 and 50 with pressure means 60 and 70 in a direction of a valve chamber 20. In the valve, The outer periphery of the first and second diaphragms 40 and 50 is held by support rings 45 and 55, and intermediate diameter distances M1 and M2 at a position dividing the maximum diameters L1 and L2 of a film section and the minimum diameters S1 and S2 of the film section in a diaphragm section of the first and second diaphragms 40 and 50 is set in a range of approximately 0.5 to 2 times an orifice diameter O. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a flow rate control valve that controls the flow rate of a fluid (liquid or gas) at a constant level, and more particularly, to a pneumatic flow rate control valve used in semiconductor manufacturing or the like.

  For example, the flow control valve 100 shown in FIG. 13 includes a valve mechanism 130 that integrally includes a valve portion 135 that seals the valve seat 125 and a diaphragm 140, and the valve portion 135 is moved forward and backward as the valve mechanism 130 moves forward and backward. The membrane part 143 of the diaphragm 140 is configured to move while opening and closing. In FIG. 13, reference numeral 111 denotes a body body, 120 denotes a valve chamber, 121 denotes a first opening on the inflow side, 122 denotes a second opening on the outflow side, 123 denotes an orifice portion, 130 denotes a valve mechanism, and 142 denotes a body body 111. It is the outer peripheral part of the diaphragm 140 to be fixed.

  In the flow rate control valve 100, when a fluid pressure fluctuation occurs on the first opening 121 side (primary side) or the second opening 122 side (secondary side), the fluctuation acts on the diaphragm 140 and the valve portion. May affect the opening of 135. Therefore, the membrane width W10 of the membrane portion 143 of the diaphragm 140 is appropriately adjusted so that the fluid pressure P11 acting on the membrane portion 143 of the diaphragm 140 and the fluid pressure P12 acting on the valve portion 135 are substantially offset. , Configured to suppress adverse effects due to fluid pressure (see, for example, Patent Document 1).

  By the way, in the field of semiconductor manufacturing or the like, the flow rate of a fluid (liquid or gas) is increased by using a pressurizing means using pressurized air when supplying a chemical solution in a cleaning process or supplying a polishing liquid (a thriller liquid) in a CMP process. A pneumatic flow control valve to be controlled is preferably used. In the cleaning process and the CMP process in the semiconductor manufacturing and the like, the flow rate of the fluid controlled by the flow rate control valve is very small (for example, several ml / min to 2000 ml / min). In addition, it is necessary to perform a corrective action quickly when it greatly affects the polishing rate or when the opening of the valve portion changes due to pressure fluctuation. Therefore, compared with the general industry, the reproducibility of the operation at the time of opening and closing the valve portion of the flow control valve, and the stability and responsiveness of the control are particularly required.

As described above, since the flow rate of the fluid controlled by the flow rate control valve is very small, it is necessary to reduce the orifice diameter and the membrane width of the diaphragm film portion in the flow rate control valve. However, in the conventional flow control valve 100, when the membrane portion 143 of the diaphragm 140 is moved when the valve portion 135 is opened and closed, the membrane portion 143 is in the normal state (143A) as shown in the schematic diagram of FIG. Since the film expands and contracts between the width W11 and the movable film width W12 (143B), particularly when the film width is small, the stress of the film portion 143 increases. Therefore, as shown in the graph of FIG. 15, the set pressure f1 of the pressurized air (pressurizing means) with respect to the opening of the valve part 135 when the valve part 135 is opened, and the above-mentioned when the valve part 135 is closed. The hysteresis error e1 due to the difference between the set pressure f2 of the pressurized air (pressurizing means) with respect to the opening degree of the valve section 135 is increased, and the valve section 135 at the predetermined set pressure of the pressurizing means by the pressurized air is increased. There has been a problem that it becomes difficult to realize reproducibility of operation, which adversely affects control response and stability.
JP 50-147225 A

  The present invention has been made in view of the above points, and particularly relates to a flow control valve used in semiconductor manufacturing or the like, by reducing the stress of the diaphragm film portion to reduce hysteresis error, thereby opening and closing the valve portion. It is intended to provide a pneumatic flow rate control valve that realizes the reproducibility of operation and improves the response and stability of control.

  That is, according to the first aspect of the present invention, in the valve chamber in which the first opening and the second opening for inflow and outflow of the fluid are provided via the valve seat, the valve portion for sealing the valve seat and the first opening side A valve mechanism body integrally including a first diaphragm disposed on the second opening and a second diaphragm disposed on the second opening side is disposed, and the first diaphragm and the second diaphragm are respectively moved toward the valve chamber by a pressurizing unit. In a valve that is pressurized at a predetermined pressure to control the flow rate of fluid flowing through the valve chamber, one of the pressurizing means of the first and second diaphragms is a spring and the other is pressurized air. In addition, the outer circumferences of the first and second diaphragms are sandwiched by support rings, and the film part maximum diameters (L1, L2) and the film part minimum of each diaphragm part in the first and second diaphragms An intermediate diameter distance (M1, M2) at a position where (S1, S2) is divided into two is within a range of about 0.5 to 2 times the orifice diameter (O) of the valve chamber. Related to pressure flow control valve.

  According to a second aspect of the present invention, there is provided the pneumatic flow rate control valve according to the first aspect, wherein a reinforcing shaft is provided at a connecting portion between the first and second diaphragms of the valve mechanism body.

  According to a third aspect of the present invention, in the first or second aspect, each intermediate diameter distance (M1, M2) of the first and second diaphragms is in a range of about 0.7 to 1.3 times the orifice diameter. According to the described pneumatic flow control valve.

  According to a fourth aspect of the present invention, there is provided the pneumatic flow control valve according to any one of the first to third aspects, wherein the pressurizing means using the pressurized air has a diaphragm for receiving pressurized air.

  According to a fifth aspect of the present invention, there is provided the pneumatic flow rate regulating valve according to any one of the first to fourth aspects, wherein the pressure applying means by the spring has a spring load adjusting portion.

  A sixth aspect of the present invention relates to the pneumatic flow control valve according to any one of the first to fifth aspects, wherein the spring or the pressurizing means using pressurized air has a spring for fine adjustment.

  According to the pneumatic flow control valve of the first aspect of the present invention, the valve seat seals the valve seat in the valve chamber in which the first opening and the second opening for inflow and outflow of the fluid are provided via the valve seat. And a valve mechanism body integrally including a first diaphragm disposed on the first opening side and a second diaphragm disposed on the second opening side, and pressurizing the first diaphragm and the second diaphragm In each of the valves configured to control the flow rate of the fluid flowing through the valve chamber by pressurizing with a predetermined pressure in the direction of the valve chamber by each means, either one of the pressurizing means of the first and second diaphragms is a spring, The other is pressurized air, and the outer circumferences of the first and second diaphragms are sandwiched by support rings, and the maximum film diameter and the film part of each diaphragm part in the first and second diaphragms Since the intermediate diameter distance at the position where the small diameter is divided into two is within the range of about 0.5 to 2 times the orifice diameter of the valve chamber, it is possible to suppress the change in the opening degree of the valve portion due to the fluid pressure fluctuation. In particular, since the membrane portion is configured by holding the outer periphery of the first and second diaphragms with a support ring, the stress of the membrane portion becomes small, and a hysteresis error when the valve portion opens and closes is generated. Thus, the reproducibility of the operation when the valve portion is opened and closed is realized, and the control response and stability can be improved. Therefore, it can be used suitably for cleaning processes such as semiconductor manufacturing, CMP processes, etc., and the productivity and quality of products such as semiconductors can be improved.

  According to Claim 2, since the reinforcing shaft is provided at the connecting portion of the first and second diaphragms of the valve mechanism body according to Claim 1, the durability and stability of the valve mechanism body is improved, and more reliably. In addition, the reproducibility of the operation of the valve portion can be realized.

  According to a third aspect, in the first or second aspect, each intermediate diameter distance of the first and second diaphragms is within a range of about 0.7 to 1.3 times the orifice diameter. It is possible to further suppress the influence of fluid pressure fluctuations on the first and second diaphragms.

  According to a fourth aspect of the present invention, in the first to third aspects, the pressurizing means using the pressurized air has a pressure receiving diaphragm for the pressurized air, so that the influence of the pressurized air on the first or second diaphragm is prevented. And the valve mechanism can be operated more reliably.

  According to a fifth aspect of the present invention, in the first to fourth aspects, since the spring pressurizing means has a spring load adjusting portion, the spring load can be finely adjusted, and the opening pressure of the valve portion can be adjusted. Adjustment can be made easily.

  According to the sixth aspect, in the first to fifth aspects, since the spring or the pressurizing means using the pressurized air has the spring for fine adjustment, the fine adjustment of the spring load can be performed with higher accuracy.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a longitudinal sectional view of a pneumatic flow rate control valve according to an embodiment of the present invention in an opened state, FIG. 2 is a longitudinal sectional view of the pneumatic flow rate control valve in a closed state, and FIG. 3 is a diagram of a first diaphragm. FIG. 4 is a cross-sectional view of the main part showing the relationship of the fluid pressure acting when the intermediate diameter distance is formed larger than the orifice diameter. FIG. 4 shows the fluid pressure acting when the intermediate diameter distance of the second diaphragm is formed larger than the orifice diameter. FIG. 5 is a cross-sectional view of the principal part showing the relationship, FIG. 5 is a cross-sectional view of the principal part showing the relation of the fluid pressure acting when the intermediate diameter distance of the first diaphragm is made smaller than the orifice diameter, and FIG. 6 is the intermediate part of the second diaphragm. FIG. 7 is a cross-sectional view of the principal part showing the relationship of fluid pressure acting when the diameter distance is made smaller than the orifice diameter, FIG. 7 is a cross-sectional view of the vicinity of the outer periphery of the first diaphragm of the same pneumatic flow control valve, 1 diaphragm membrane part possible FIG. 9 is a schematic diagram showing the state, FIG. 9 is a graph showing the relationship between the set pressure of the pressurizing means by the pressurized air of the pneumatic flow control valve and the opening or flow rate of the valve part, and FIG. 10 is another embodiment. FIG. 11 is a longitudinal sectional view of the pneumatic flow rate regulating valve in the opened state, FIG. 11 is a longitudinal sectional view of the pneumatic flow rate regulating valve in the closed state, and FIG. 12 is a set pressure of the pressurizing means of the pneumatic flow regulating valve. It is the graph showing the relationship between the opening degree or flow volume of a valve part.

  The pneumatic flow rate control valve 10 according to one embodiment of the present invention shown in FIGS. 1 and 2 includes a valve chamber 20, a valve mechanism 30, and pressurizing means 60 and 70. In the figure, reference numeral 11 denotes a body body made of a resin having high corrosion resistance and chemical resistance such as fluororesin.

  The valve chamber 20 is formed in the body main body 11, and a first opening 21 and a second opening 22 for flowing in and out of the fluid are provided through a valve seat 25. Reference numeral 23 denotes an orifice portion, 26 denotes a first opening side valve chamber, 27 denotes a second opening side valve chamber, and 28 denotes a connection flow path between the first opening side valve chamber 26 and the second opening side valve chamber 27. In the embodiment, the first opening 21 is a fluid inflow side (primary side), and the second opening 22 is a fluid outflow side (secondary side).

  As shown in FIGS. 1 to 4, the valve mechanism 30 is disposed in the valve chamber 20, a valve portion 35 that seals the valve seat 25, a first diaphragm 40 disposed on the first opening 21 side, and a second diaphragm 30. It has the 2nd diaphragm 50 distribute | arranged to the opening 22 side integrally. The valve mechanism body 30 of the embodiment is made of a highly corrosion-resistant and chemical-resistant resin such as a fluororesin like the body main body 11, and the first diaphragm 40 and the second diaphragm 50 are integrated with each other through the connecting portion 31. In addition, a valve portion 35 is formed on the first opening side valve chamber 26 side of the connecting portion 31 so as to open and close the orifice portion 23.

  As shown in FIG. 3, the valve portion 35 of the valve mechanism 30 includes a pressure receiving surface 36 for fluid pressure from the first opening 21 side and a pressure receiving surface 37 for fluid pressure from the second opening 22 side. In the valve portion 35 of the embodiment, the pressure receiving surface 36 is a tapered surface on the front side of the valve portion 35 formed inside the orifice portion 23, and the pressure receiving surface 37 is formed inside the orifice portion 23. It is a taper surface on the rear side of the valve portion 35. In the figure, reference numeral 38 denotes a tapered surface outside the orifice portion 23 formed continuously with the pressure receiving surface 36, and 39 denotes a flat surface behind the valve portion 35 formed outside the orifice portion 23. To express.

  As shown in FIGS. 3, 5, and 7, the first diaphragm 40 is integrally formed on the first opening 21 side of the connecting portion 31, and has a thin diaphragm portion 41 and an outer peripheral portion fixed to the body main body 11. 42, and the outer periphery of the first diaphragm 40 is sandwiched by the support ring 45. In the first diaphragm 40, the support ring 45 sandwiches the outer peripheral portion 42 and the outer peripheral portion of the diaphragm portion 41 to form a film portion (movable portion) 43 having a pressure receiving surface 41a on which fluid pressure acts. The intermediate diameter distance M1 at a position where the maximum diameter L1 and the minimum diameter S1 of the film portion 43 are divided into two is configured to be within a range of about 0.5 to 2 times the orifice diameter O.

  The intermediate diameter distance M1 at the position where the maximum diameter L1 and the minimum diameter S1 of the membrane portion 43 of the first diaphragm 40 are divided into two is the fluid pressure from the first opening 21 side with respect to the pressure receiving surface 41a of the membrane portion 43. This can be considered as the effective pressure receiving diameter of the membrane portion 43 of the first diaphragm 40 when P1 acts. Further, in the valve portion 35, when the fluid pressure is received from the first opening 21 side, the fluid pressures P3 and P4 acting on the tapered surface 38 and the flat surface 39 outside the orifice portion 23 are canceled out. The fluid pressure P2 from the opening 21 side can be considered as acting on the pressure receiving surface 36 of the valve portion 35.

  Therefore, as shown in FIG. 3, when the intermediate diameter distance M1 of the membrane portion 43 of the first diaphragm 40 is larger than the orifice diameter O (here, within a range of 1 to 2 times), the fluid pressures P1, P2 Can be substantially offset, and the influence of the pressure fluctuation of the fluid on the first opening 21 side with respect to the first diaphragm 40 can be suppressed. When the intermediate diameter distance M1 is formed to be larger than twice the orifice diameter O, the fluid pressure P1 acting on the film portion 43 of the first diaphragm 40 becomes too large to be canceled by the fluid pressure P2. The pressure fluctuation on the first opening 21 side (primary side) affects the opening degree of the valve portion 35, making it difficult to control the opening degree appropriately.

  Further, as shown in FIG. 5, even when the intermediate diameter distance M1 of the film portion 43 of the first diaphragm 40 is smaller than the orifice diameter O (here, within a range of 0.5 to 1 times), The fluid pressures P1 and P2 can be substantially canceled out, and the influence of the pressure fluctuation of the fluid on the first opening 21 side with respect to the first diaphragm 40 can be suppressed. When the intermediate diameter distance M1 is formed to be smaller than 0.5 times the orifice diameter O, the fluid pressure P1 acting on the membrane portion 43 of the first diaphragm 40 becomes too small to be canceled by the fluid pressure P2. For this reason, the pressure fluctuation on the first opening 21 side (primary side) affects the opening degree of the valve portion 35, making it difficult to control the opening degree appropriately.

  Therefore, by setting the intermediate diameter distance M1 within the range of about 0.5 to 2 times the orifice diameter O, the fluid pressures P1 and P2 can be substantially canceled out, and the first opening 21 with respect to the first diaphragm 40 is obtained. The influence of the pressure fluctuation of the side fluid can be suppressed. In particular, if the intermediate diameter distance M1 is within the range of about 0.7 to 1.3 times the orifice diameter O, the influence of the pressure fluctuation of the first opening 21 side fluid on the first diaphragm 40 can be further suppressed. it can.

  Further, in the first diaphragm 40 configured as described above, the outer periphery of the first diaphragm 40 (the outer peripheral side portion and the outer peripheral portion 42 of the diaphragm portion 41) is sandwiched by the support ring 45 to form the film portion 43. Therefore, when the valve part 35 is opened and closed, the film part 43 moves relative to the entire diaphragm part 41. That is, as shown in FIG. 8, the film portion 43 has a normal width (43 </ b> A) from the film width W <b> 4 with respect to the diaphragm portion 41 full width W <b> 1 (outer peripheral side width W <b> 3 + normal film width 43 </ b> A film width W <b> 4) It expands and contracts between the film width W2 when it is movable (43B). Therefore, it is possible to reduce the stress of the film portion 43 when it is movable as compared with the conventional case, and it is possible to reduce a hysteresis error when the valve portion 35 of the valve mechanism 30 is opened and closed.

  On the other hand, as shown in FIGS. 4 and 6, the second diaphragm 50 is integrally formed on the second opening 22 side of the connecting portion 31, and has a thin diaphragm portion 51 and an outer peripheral portion 52 fixed to the body body 11. The outer periphery of the second diaphragm 50 is configured to be held by the support ring 55. Similar to the first diaphragm 40, the second diaphragm 50 has a pressure receiving surface 51a on which the outer peripheral portion 52 and the outer peripheral portion of the diaphragm portion 51 are sandwiched by the support ring 55 and the fluid pressure acts on. A film part (movable part) 53 is formed, and an intermediate diameter distance M2 at a position where the maximum diameter L2 and the minimum diameter S2 of the film part 53 are divided into two is within a range of about 0.5 to 2 times the orifice diameter O. It is comprised so that.

  The intermediate diameter distance M2 at the position where the maximum diameter L2 and the minimum diameter S2 of the membrane portion 53 of the second diaphragm 50 are divided into two is the fluid pressure from the second opening 22 side with respect to the pressure receiving surface 51a of the membrane portion 53. It can be considered as the effective pressure receiving diameter of the membrane portion 53 of the so-called second diaphragm 50 when P5 acts. Further, in the valve portion 35, when fluid pressure is received from the second opening 22 side, the fluid pressure P6 from the second opening 22 side can be considered as acting on the pressure receiving surface 37 of the valve portion 35.

  Therefore, as shown in FIG. 4, when the intermediate diameter distance M2 of the membrane portion 53 of the second diaphragm 50 is formed larger than the orifice diameter O (here, within a range of 1 to 2 times), the fluid pressures P5 and P6 are used. Can be substantially offset, and the influence of the pressure fluctuation of the fluid on the second opening 22 side with respect to the second diaphragm 50 can be suppressed. When the intermediate diameter distance M2 is formed to be larger than twice the orifice diameter O, the fluid pressure P5 acting on the membrane portion 53 of the second diaphragm 50 becomes too large to be canceled by the fluid pressure P6. The pressure fluctuation on the second opening 22 side (secondary side) affects the opening degree of the valve portion 35, so that proper opening degree control becomes difficult.

  Further, as shown in FIG. 6, even when the intermediate diameter distance M2 of the film portion 53 of the second diaphragm 50 is smaller than the orifice diameter O (here, within a range of 0.5 to 1 times), The fluid pressures P5 and P6 can be substantially canceled, and the influence of the pressure fluctuation of the fluid on the second opening 22 side with respect to the second diaphragm 50 can be suppressed. When the intermediate diameter distance M2 is smaller than 0.5 times the orifice diameter O, the fluid pressure P5 acting on the membrane portion 53 of the second diaphragm 50 becomes too small to be canceled by the fluid pressure P6. For this reason, the pressure fluctuation on the second opening 22 side (secondary side) affects the opening degree of the valve portion 35, making it difficult to control the opening degree appropriately.

  Therefore, by setting the intermediate diameter distance M2 within the range of about 0.5 to 2 times the orifice diameter O, the fluid pressures P5 and P6 can be substantially canceled out, and the second opening 22 with respect to the second diaphragm 50 is obtained. The influence of the pressure fluctuation of the side fluid can be suppressed. In particular, if the intermediate diameter distance M2 is within the range of about 0.7 to 1.3 times the orifice diameter O, the influence of the pressure fluctuation of the fluid on the second opening 22 side on the second diaphragm 50 can be further suppressed. it can.

  Also in the second diaphragm 50, as in the first diaphragm 40, the outer periphery (the outer peripheral side portion and the outer peripheral portion 52 of the diaphragm portion 51) is sandwiched by the support ring 55 to form the film portion 53. Therefore, it is possible to reduce the stress of the film portion 53 when moving compared to the conventional case, and to reduce the hysteresis error.

  The pressurizing means 60 and 70 are configured to pressurize the first diaphragm 40 and the second diaphragm 50 in the direction of the valve chamber 20 with a predetermined pressure, respectively, and control the flow rate of the fluid flowing through the valve chamber 20. In the embodiment, the pressurizing means 60 on the first opening 21 side is pressurized air, and the pressurizing means 70 on the second opening 22 side is a spring. In the figure, reference numeral 61 denotes a first opening side pressurizing chamber, and 71 denotes a second opening side pressurizing chamber.

  The pressurizing means 60 using pressurized air adjusts the opening degree of the valve portion 35 and the flow rate of the liquid to a predetermined amount by appropriately setting the pressurized air. In the embodiment, as described above, since the outer periphery of each diaphragm 40, 50 is sandwiched between the support rings 45, 55 and no hysteresis error occurs, as shown in the graph of FIG. The set pressure F1 of the pressurizing means 60 is kept constant. As a result, when the set pressure of the pressurized air is equal to or greater than the opening pressure a value of the valve portion 35, the valve portion 35 is closed and the fluid flow rate becomes zero. Further, by opening the set pressure to the opening pressure a value or less, the valve portion 35 is opened and a predetermined flow rate of fluid flows. By adjusting the set pressure lower, the opening of the valve portion 35 is increased. As a result, the flow rate also increases. Thus, if the opening degree and flow rate of the valve unit 35 are adjusted by the pressurizing means (pressurized air) 60, the set pressure can be easily adjusted and a large set pressure is required. Is also effective.

  Further, in the pressurizing means 60 using pressurized air, it is preferable to provide a diaphragm 65 for receiving pressurized air as shown in FIGS. 1 and 2 and defined as the invention of claim 4. The pressure receiving diaphragm 65 is disposed in the first opening side pressurizing chamber 61 so that the pressurized air of the pressurizing means 60 does not act on the first diaphragm 40. The pressure receiving diaphragm 65 is always urged from the valve chamber 20 side by a pressure receiving diaphragm auxiliary member 62 formed integrally with the connecting portion 31 of the valve mechanism 30, and the pressurizing means 60 pressurizes the pressure receiving diaphragm 65. When the air is adjusted, the valve mechanism 30 is operated via the pressure-receiving diaphragm auxiliary member 62. Thus, by having the pressure receiving diaphragm 65, the influence of the pressurized air with respect to the 1st diaphragm 40 can be prevented, and the valve mechanism 30 can be operated more reliably.

  The pressurizing means 70 using a spring constantly biases and holds the second diaphragm 50 in the direction of the valve chamber 20 with a constant spring load, and is based on the pressurizing means (pressurized air) 60 according to the load of the spring. The opening pressure a of the valve part 35 is set. Reference numeral 72 in the figure denotes a spring holder for the pressurizing means 70 using a spring, which is formed integrally with the connecting portion 31 of the valve mechanism 30.

  In the pressurizing means 70, it is preferable to provide a spring load adjusting portion 73 as defined in the invention of claim 5. As shown in FIG. 9, the adjusting portion 73 can adjust the opening pressure of the valve portion 35 to be small (a1) by adjusting the spring load to be large (c1), and the spring load becomes small. By adjusting (c2) as described above, the opening pressure of the valve portion 35 can be set large (a2). Thus, by providing the adjusting unit 73 in the pressurizing means 70 using a spring, the spring load can be finely adjusted, and the opening pressure of the valve unit 35 can be easily adjusted.

  In the pneumatic flow control valve 10, as shown in FIGS. 1 and 2 and defined as the invention of claim 2, a reinforcing shaft 32 may be provided at the connecting portion 31 of the first and second diaphragms 40 and 50. Preferably recommended. As the reinforcing shaft 32, a metal or a resin material having excellent durability such as polyether ether ketone is used. By providing the reinforcing shaft 32 in this way, the durability of the connecting portion 31 of the valve mechanism 30 is improved. For example, when the load of the pressurizing means 70 by a spring is increased, Even if an excessive load is applied, problems such as the dimensional change and buckling of the valve mechanism 30 can be suppressed. Therefore, the stability of the valve mechanism 30 is improved, and the reproducibility of the operation of the valve portion 35 can be realized more reliably.

  In the pneumatic flow control valve 10 configured as described above, the membrane portions 43, 53 maximum diameters L1, L2 and the membrane portions 43, 53 minimum diameter of the diaphragm portions 41, 51 in the first and second diaphragms 40, 50, respectively. Since the intermediate diameter distances M1 and M2 at positions where S1 and S2 are divided into two are within the range of about 0.5 to 2 times the orifice diameter O of the valve chamber 20, the pressure of the fluid A change in the opening degree of the valve portion 35 due to the fluctuation can be suppressed. In particular, since the outer periphery of the first and second diaphragms 40 and 50 is sandwiched by support rings 45 and 55 to form the film parts 43 and 53, the stress of the film parts 43 and 53 is reduced. Hysteresis error when the valve unit 35 opens and closes can be reduced, the reproducibility of the operation when the valve unit 35 is opened and closed is realized, the adverse effect due to the lack of reproducibility is eliminated, and the control response and stability are reduced. improves. Therefore, it can be suitably used particularly for supplying chemicals in cleaning processes such as semiconductor manufacturing, supplying polishing liquid (thriller liquid) in CMP processes, and the like, and improving the productivity and quality of products such as semiconductors.

  Next, a pneumatic flow control valve 10A according to another embodiment will be described with reference to FIGS. This flow control valve 10A includes a pressurizing unit 80 using a spring on the first opening 21 side (primary side) and a pressurizing unit 90 using pressurized air on the second opening 22 side (secondary side). Reference numeral 81 in the figure denotes a first opening-side pressurizing chamber, and 91 denotes a second opening-side pressurizing chamber. In the following description, the same reference numerals as those of the flow rate control valve 10 represent the same configuration, and the description thereof is omitted.

  The pressurizing means 80 using a spring constantly biases and holds the first diaphragm 40 in the direction of the valve chamber 20 with a constant spring load. A pressurizing means (pressurized air) 90 described later according to the load of the spring. The opening pressure b of the valve part 35 is set. Reference numeral 82 in the figure is a spring holder for the pressurizing means 80 by a spring formed integrally with the connecting portion 31 of the valve mechanism 30, and 83 is an exhaust port of the pressurizing means 80.

  The pressurizing means 90 using pressurized air adjusts the opening degree of the valve portion 35 and the flow rate of the liquid to a predetermined amount by appropriately setting the pressurized air. As in the case of the pneumatic flow rate control valve 10, in this embodiment, the outer periphery of each diaphragm 40, 50 is held between the support rings 45, 55, so that no hysteresis error occurs. Therefore, as shown in the graph of FIG. The set pressure F2 of the pressurizing means 90 corresponding to the opening degree of the valve part 35 is kept constant. When the set pressure of the pressurized air is set to the opening pressure b value or less of the valve portion 35, the valve portion 35 is closed and the fluid flow rate becomes zero. Further, by opening the set pressure to the opening pressure b value or more, the valve portion 35 is opened and a predetermined flow rate of fluid flows. By adjusting the set pressure higher, the opening of the valve portion 35 is increased. As a result, the flow rate also increases.

  In the pressurizing means 90, it is preferable to arrange a pressure receiving diaphragm 95 in the second opening side pressurizing chamber 91 so that the pressurized air of the pressurizing means 90 does not act on the second diaphragm 50. The pressure receiving diaphragm 95 is always urged from the valve chamber 20 side by a pressure receiving diaphragm auxiliary member 92 formed integrally with the connecting portion 31 of the valve mechanism 30, and the pressurized air of the pressurizing means 90 is compressed. When the adjustment is performed, the valve mechanism 30 is operated via the pressure-receiving diaphragm auxiliary member 92. Further, the pressure receiving diaphragm 95 prevents the influence of the pressurized air on the second diaphragm 50, similarly to the pressure receiving diaphragm 65 described above.

  Further, in the pressurizing means 90, as shown in FIGS. 10 and 11 and defined as the invention of claim 6, a fine adjustment spring 93 may be provided. As the fine adjustment spring 93, a spring having a spring constant lower than the spring load of the pressurizing means 80 is used. By adjusting the load in the direction of the valve chamber 20 with a fine adjustment screw 94, the pressurizing means is appropriately adjusted. The spring load of 80 can be finely adjusted with higher accuracy. In the figure, reference numeral 96 denotes a spring holder of a fine adjustment spring 93 that urges the valve mechanism 30 toward the valve chamber 20, and 97 denotes a spring holder of the fine adjustment spring 93 into which a fine adjustment screw 94 is inserted. .

  The pneumatic flow control valve of the present invention is not limited to the configuration described in the above embodiment, and can be implemented with various modifications without departing from the spirit of the invention. For example, in the embodiment, the fine adjustment spring 93 is provided in the pressurizing means 90 using pressurized air, but it can also be provided in the pressurizing means 80 using a spring.

  Further, an adjustment part for adjusting the spring load may be provided in the pressurizing means 80 by the spring of the flow rate adjusting valve 10A so that the opening pressure of the valve part 35 can be adjusted.

It is a longitudinal cross-sectional view of the open state of the pneumatic flow control valve according to one embodiment of the present invention. It is a longitudinal cross-sectional view of the closed state of the pneumatic flow rate control valve. It is principal part sectional drawing which showed the relationship of the fluid pressure which acts when the intermediate diameter distance of a 1st diaphragm is formed larger than an orifice diameter. It is principal part sectional drawing which showed the relationship of the fluid pressure which acts when the intermediate diameter distance of a 2nd diaphragm is formed larger than an orifice diameter. It is principal part sectional drawing which showed the relationship of the fluid pressure which acts when the intermediate diameter distance of a 1st diaphragm is formed smaller than an orifice diameter. It is principal part sectional drawing which showed the relationship of the fluid pressure which acts when the intermediate diameter distance of a 2nd diaphragm was formed smaller than an orifice diameter. It is sectional drawing of the outer peripheral part vicinity of the 1st diaphragm of the pneumatic type flow control valve. It is a schematic diagram showing the movable state of the film | membrane part of a 1st diaphragm. It is the graph showing the relationship between the setting pressure of the pressurization means by the pressurized air of the pneumatic pressure type flow control valve and the opening degree or flow rate of the valve part. It is a longitudinal cross-sectional view of the open state of the pneumatic flow control valve according to another embodiment. It is a longitudinal cross-sectional view of the closed state of the pneumatic flow rate control valve. It is a graph showing the relationship between the set pressure of the pressurizing means of the same pneumatic flow control valve and the opening or flow rate of the valve part. It is principal part sectional drawing of the conventional flow control valve comprised so that the fluid pressure which acts on a diaphragm and a valve part may be canceled. It is the schematic diagram showing the movable state of the film | membrane part of the diaphragm in the flow control valve of FIG. It is the graph showing the relationship between the setting pressure of the pressurization means of the conventional pneumatic type flow control valve, and the opening degree or flow volume of a valve part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pneumatic flow control valve 11 Body main body 20 Valve chamber 21 1st opening 22 2nd opening 23 Orifice part 25 Valve seat 26 1st opening side valve chamber 27 2nd opening side valve chamber 28 Connection flow path 30 Valve mechanism 31 Connection Part 32 Reinforcing shaft 35 Valve part 40 First diaphragm 41 Diaphragm part 42 Outer part of first diaphragm 43 Film part of first diaphragm 45 Support ring of first diaphragm 50 Second diaphragm 51 Diaphragm part 52 Outer part of second diaphragm 53 Membrane part of the second diaphragm 55 Support ring of the second diaphragm 60 Pressurizing means by pressurized air 61 First opening side pressurizing chamber 62 Diaphragm auxiliary member for receiving pressure 65 Diaphragm for receiving pressure 70 Pressurizing means by spring 71 Second opening Side pressurization chamber 72 Spring holder 73 Adjustment part L1 , L2 Membrane maximum diameter M1, M2 Intermediate diameter distance O Orifice diameter S1, S2 Membrane minimum diameter

Claims (6)

A valve chamber in which a first opening and a second opening for inflow and outflow of fluid are provided via a valve seat, a valve portion for sealing the valve seat, a first diaphragm disposed on the first opening side, and the A valve mechanism body integrally including a second diaphragm disposed on the second opening side is disposed, and the first diaphragm and the second diaphragm are respectively pressurized with a predetermined pressure in a valve chamber direction by a pressurizing unit, and the valve chamber is In a valve that controls the flow rate of fluid flowing through
While either one of the pressurizing means of the first and second diaphragms is a spring and the other is a pressurized air,
The outer peripheries of the first and second diaphragms are sandwiched by support rings, and the film part maximum diameters (L1, L2) and film part minimum diameters (S1, S2) of the respective diaphragm parts in the first and second diaphragms are set. A pneumatic flow control valve characterized in that an intermediate diameter distance (M1, M2) at a position divided into two is within a range of about 0.5 to 2 times the orifice diameter (O) of the valve chamber.   2. The pneumatic flow control valve according to claim 1, further comprising a reinforcing shaft at a connecting portion between the first diaphragm and the second diaphragm of the valve mechanism body.   The pneumatic flow control valve according to claim 1 or 2, wherein each of the intermediate diameter distances (M1, M2) of the first and second diaphragms is within a range of about 0.7 to 1.3 times the orifice diameter. .   The pneumatic flow control valve according to any one of claims 1 to 3, wherein the pressurizing means using the pressurized air has a pressure receiving diaphragm for pressurized air.   The pneumatic flow rate control valve according to any one of claims 1 to 4, wherein the pressurizing means using the spring has a spring load adjusting portion.   6. The pneumatic flow control valve according to claim 1, wherein the spring or the pressurizing means using pressurized air has a spring for fine adjustment.

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