JP2007058339A - Fluid control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manual or open loop control type fluid control device that facilitates installation, piping and wiring in a semiconductor manufacturing apparatus or the like, enables constant stable fluid control and facilitates fluid cutoff by a simple structure without feedback control, and ensures flow control even when a pulsating fluid flows. <P>SOLUTION: The fluid control device of a manual or open loop control type comprises a fluid control valve for controlling the pressure of a fluid in response to a pressure operation of a control fluid, and a switch valve for opening or stopping the flow of the fluid. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluid control device used in a fluid transportation pipe that requires fluid control. More specifically, it is mainly easy to install in semiconductor manufacturing equipment, piping and wiring connections, and can control fluid stably and stably with a simple configuration without using feedback control, and it is easy to shut off fluid. Further, the present invention relates to a manual or open loop control type fluid control device capable of controlling the flow rate without any problem even when a pulsating fluid flows.

  Conventionally, wet etching, in which a wafer surface is etched using cleaning water obtained by diluting a chemical solution such as hydrofluoric acid with pure water, is used as one step of a semiconductor manufacturing process. It is said that the concentration of cleaning water for these wet etching needs to be managed with high accuracy. In recent years, the method of managing the concentration of cleaning water by the flow rate ratio of pure water and chemical liquid has become the mainstream, and therefore, a fluid control device that manages the flow volume of pure water or chemical liquid with high accuracy has been applied. Yes.

  Various fluid control devices have been proposed, but there has been a pure water flow rate control device 201 that performs flow rate control when the pure water temperature is variable as shown in FIG. 7 (see, for example, Patent Document 1). The configuration includes a flow rate adjusting valve 202 that is adjusted in opening degree under the action of an operating pressure to adjust the pure water flow rate, and an operating pressure adjusting valve 203 for adjusting the operating pressure supplied to the flow rate adjusting valve 202. A flow rate measuring device 204 for measuring the flow rate of pure water output from the flow rate adjusting valve 202, and an on-off valve 205 for allowing or blocking the flow of pure water that has passed through the flow rate measuring device 204. A control device that controls the pure water flow rate output from the flow rate adjustment valve 202 to be constant by balancing the operation pressure adjusted by the pressure adjustment valve 203 and the output pressure of pure water in the flow rate adjustment valve 202. 201 for feedback control of the operating pressure supplied from the operating pressure adjusting valve 203 to the flow adjusting valve 202 based on the measured value so that the measured value by the flow measuring device 204 is constant. It was characterized in that a control circuit. The effect is that even if the output pressure at the flow rate adjustment valve 202 changes with the temperature change of the pure water, the operation pressure is adjusted in real time in accordance with the change, so that the output pressure is output from the flow rate adjustment valve 202. Since the pure water flow rate is adjusted, the pure water flow rate can be maintained at a constant value with high accuracy.

  Further, as a manual or open-loop control type fluid control device, there is a pressure reducing valve 301 that can switch a set pressure for operation as shown in FIG. Reference 2). The main valve that embeds a plurality of pilot valves set at different operating pressures in the pressure reducing valve body, and that controls the opening and closing of the main valve by receiving the primary side pressure of the pressure reducing valve body on the inflow side of these pilot valves. And a means for allowing only the pilot valve set at a desired operating pressure to be selectively operated by allowing the outlet side to be connected to the secondary flow path of the pressure reducing valve body. there were. The effect is that it is possible to obtain a pressure reducing valve capable of quickly and surely switching the set pressure of the reduced pressure.

JP-A-11-161342 JP 10-39935 A

  However, since the conventional pure water flow rate control device 201 employs a feedback control method, it is necessary to provide a control unit, and installation and wiring for that purpose are complicated. Since the control unit is assembled with parts that are vulnerable to corrosion, unless corrosive resistance is taken, the permeated corrosive gas will corrode the components in the control unit when flowing corrosive fluid. There is a problem that accurate control may not be performed.

  The conventional pressure reducing valve 301 is manually controlled (self-control), but has many parts and takes time to assemble the valve. Since the valve itself is not compact, the fluid control device becomes large. The fluid cannot be monitored when the fluid is controlled. For this reason, there has been a problem that it cannot be confirmed whether the fluid state is good or not.

  The present invention has been made in view of the above-described problems of the prior art, and can be easily installed in a semiconductor manufacturing apparatus or the like, connected to piping and wiring, and has a simple configuration without using feedback control. The object of the present invention is to provide a manual or open-loop control type fluid control device that can control the flow rate stably and easily, and can easily shut off the fluid, and can control the flow rate without any problem even if a pulsating fluid flows. .

A configuration of a fluid control device of the present invention for solving the above-described problems will be described with reference to FIGS.
The manual or open loop control type fluid control device 1 of the present invention includes a fluid control valve 4 that controls the pressure of a fluid by a pressure operation of a control fluid, and an on-off valve that opens or shuts off the flow of the fluid. It has the first feature.
The control fluid refers to, for example, air or hydraulic oil.

  A second feature is that the fluid control valve and the on-off valve are arranged in one base block.

In addition, the fluid control valve is provided with a second gap provided in the center of the lower part to be opened to the bottom, an inlet channel communicating with the second gap, and an upper face provided in the upper part with a diameter of the second gap. A communication hole having a diameter smaller than the diameter of the first gap, the first gap having a larger diameter, the outlet channel communicating with the first gap, the first gap, and the second gap. A cylindrical gap communicating with a main body having a valve seat on the upper surface of the second gap and a supply hole and a discharge hole provided on the side surface or the upper face. A bonnet provided with a stepped portion, a spring receiver fitted into the stepped portion of the bonnet and having a through hole in the central portion, and a first joint portion having a diameter smaller than the through hole of the spring receiver at the lower end portion and a flange portion at the upper portion And a piston that is inserted into the gap of the bonnet so as to be movable up and down, a lower end surface of the flange of the piston, and a spring A central portion that forms a first valve chamber in such a manner that the spring held by the upper end surface of the frame and the peripheral edge portion are clamped and fixed between the main body and the spring receiver and cover the first gap of the main body. The first diaphragm is made thick, the second joint is joined and fixed to the first joint of the piston through the through hole of the spring receiver at the center of the upper surface, and the communication hole of the main body is penetrated to the center of the lower surface. A first valve mechanism having a third joint provided, a valve located inside the second gap of the main body and having a diameter larger than the communication hole of the main body, and protruding from the upper end surface of the valve body A fourth joint portion that is joined and fixed to the third joint portion of the first valve mechanism body, a rod that protrudes from the lower end surface of the valve body, and a second portion that extends in the radial direction from the lower end surface of the rod. A second valve mechanism having a diaphragm and a second diaphragm peripheral portion of the second valve mechanism located below the main body A base plate having a protrusion at the center of the upper portion, a notch recess provided at the upper end of the protrusion, and a breathing hole communicating with the notch recess. A third feature is that the opening area of the fluid control unit formed by the valve body of the second valve mechanism and the valve seat of the main body changes with the movement.
The basic configuration of this control valve is disclosed in Japanese Patent Application Laid-Open No. 2004-38571.

The fluid control valve includes a fluid inlet channel, an outlet channel, a main body formed from a chamber in which the inlet channel and the outlet channel communicate with each other, a valve member having a valve body and a first diaphragm portion; The second diaphragm part and the third diaphragm part located at the lower part and the upper part of the valve member and having a smaller effective pressure receiving area than the first diaphragm part, and the outer peripheral part of each diaphragm part is the main body part The chamber is divided into a first pressurizing chamber, a second valve chamber, a first valve chamber, and a second pressurizing chamber by each diaphragm portion. Means for constantly applying a constant inward force to the second diaphragm portion, the first valve chamber is in communication with the inlet channel, and the second valve chamber is a valve corresponding to a valve element of the valve member; Has a seat and a first diaphragm against the valve seat A lower second valve chamber that communicates with the first valve chamber through a communication hole that is located on the side and provided in the first diaphragm portion, and is disposed on the second diaphragm portion side and communicated with the outlet channel. It has a fluid control part that is formed separately from the upper second valve chamber and that controls the fluid pressure in the lower second valve chamber by changing the opening area between the valve element and the valve seat by the vertical movement of the valve member. The second pressurizing chamber has a fourth feature in that it has means for constantly applying a constant inward force to the third diaphragm portion.
The basic configuration of this control valve is disclosed in Japanese Patent Application Laid-Open No. 2004-176812.

  In the present invention, the fluid control valve 4 is not particularly limited as long as the fluid pressure can be controlled by controlling the pressure of the control fluid. However, the fluid control valve 4 of the present invention performs the fluid pressure control as shown in FIG. What has the structure of the fluid control valve 4 or the fluid control valve 169 of the present invention for controlling the flow rate of the fluid as shown in FIG. 5 is preferable. This enables stable fluid control, and even if the pulsating fluid flows, the fluid control valves 4 and 169 can stabilize the pressure or flow rate to a constant pressure, and the fluid control valves 4 and 169 can be used as flow paths only. This is preferable because the fluid control device 1 can be provided in a small size.

  In the present invention, as shown in FIG. 1, the fluid control valve 4 is provided with an on-off valve 61. This is preferable because the on-off valve 61 is provided so that the on-off valve 61 is shut off so that maintenance, repair, and part replacement (hereinafter referred to as maintenance or the like) of the fluid control device 1 can be easily performed. If the fluid control valve 4 is provided with the opening / closing valve 61, when the fluid control valve 4 is disassembled for maintenance or the like by shutting off the flow path, the fluid remaining in the flow path leaks from the decomposed portion. It is preferable that the fluid can be kept to a minimum, and the fluid can be urgently shut off by the on-off valve 61 when any trouble occurs in the flow path.

  Further, the configuration of the on-off valve 61 is not particularly limited as long as it has a function of opening or shutting off the fluid flow, and may be manually operated, such as by air drive, electric drive, or magnetic drive. It may be. When trouble occurs in the fluid control valve 4, the flow path can be urgently shut off by the on-off valve 61.

  Moreover, the order of installation of the fluid control valve 4 and the on-off valve 61 may be provided in any order and is not particularly limited. However, the installation position of the on-off valve 61 is determined by the fluid control valve 4 in order to perform maintenance or the like. It is desirable to install it upstream. Further, a plurality of on-off valves 61 may be provided on both the upstream side and the downstream side of the fluid control valve 4. At this time, by closing both the on-off valves 61, the upstream and downstream flows of the fluid control valve 4 are stopped, so that the backflow of the fluid is prevented, and fluid leakage is ensured when performing maintenance or the like. It is suitable for being prevented.

  In the fluid control apparatus of the present invention, as shown in FIGS. 1 and 4, the valves 4, 61, and 169 are preferably disposed in one base block 147, 147 x in which a flow path is formed. This is because each component is arranged in one base block 147, 147x, the fluid control device can be made compact and the installation space can be reduced, the installation work becomes easy and the work time is shortened. Since the flow path in the fluid control device can be shortened to the minimum necessary, the fluid resistance can be suppressed, and the number of parts can be reduced, so that the assembly of the fluid control device can be facilitated. Therefore, it is preferable.

  In addition, the fluid control device of the present invention may be used for any application that requires constant control of the fluid flow rate at an arbitrary value, but is preferably disposed in a semiconductor manufacturing apparatus. It is. The pre-process of the semiconductor manufacturing process includes a photoresist process, a pattern exposure process, an etching process, a flattening process, etc., and the concentration of these cleaning waters is controlled by the flow rate ratio of pure water and chemicals. It is preferable to use a fluid control device.

  The material of each component of the fluid control valve 4 and the on-off valve 61 of the present invention may be any of vinyl chloride, polypropylene (hereinafter referred to as PP), polyethylene, etc., as long as it is made of resin. Fluorine resins such as polytetrafluoroethylene (hereinafter referred to as PTFE), polyvinylidene fluoride (hereinafter referred to as PVDF), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin (hereinafter referred to as PFA), etc. If it is made of a fluororesin, it can be used as a corrosive fluid, and even if corrosive gas permeates, there is no risk of corrosion of the valves 4 and 61, which is preferable.

The present invention has the structure as described above, and the following excellent effects can be obtained.
(1) Since a manual or open loop control method is adopted instead of the feedback control method, it is not necessary to provide a control unit, or even if necessary, the configuration of the control unit is simpler than the feedback control method. . In the case of manual control, installation of the control unit and complicated wiring therefor are unnecessary. Since the control unit is assembled with parts that are vulnerable to corrosion, unless corrosive resistance is taken, the permeated corrosive gas will corrode the components in the control unit when flowing corrosive fluid. There was a risk that accurate control would not be performed. In the case of manual control, such a fear disappears.
(2) Since the fluid control device is disposed on one base block in which the flow path is formed, the fluid control device can be made compact and installation space can be reduced, and installation work is facilitated. The working time can be shortened, the flow path in the fluid control device can be shortened to the minimum necessary, the fluid resistance can be suppressed, and the number of parts can be reduced, making assembly of the fluid control device easy. can do.
(3) By using the fluid control valve of the configuration of the present invention, stable fluid control can be performed, and even if pulsating fluid flows, the pressure or flow rate can be stabilized at a constant pressure by the fluid control valve. The flow path can be blocked only by the fluid control valve, and the fluid control device can be provided small because of the compact configuration.
(4) By providing an opening / closing valve in the fluid control device, the fluid control device can be easily maintained, repaired, and replaced by closing the opening / closing valve without causing the fluid to leak. When some trouble occurs in the road, an emergency shutoff of the fluid can be performed with the on-off valve.
(5) By selecting one of the two types of control valves, it is possible to set the control target to either the pressure or flow rate of the fluid. Thereby, various demands for fluid control can be met.

  Hereinafter, embodiments of the present invention will be described with reference to examples shown in the drawings. However, it is needless to say that the present invention is not limited to the examples. FIG. 1 is a longitudinal sectional view of a fluid control apparatus showing a first embodiment of the present invention. FIG. 2 is an enlarged view of the fluid control valve of FIG. FIG. 3 is an enlarged view of the on-off valve of FIG. FIG. 4 is a longitudinal sectional view of a fluid control apparatus showing a second embodiment of the present invention. FIG. 5 is an enlarged view of the fluid control valve of FIG. 6 is the same as FIG. 5 with another display added to FIG.

  A fluid control apparatus according to a first embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, reference numeral 1 denotes a fluid control device installed in a semiconductor manufacturing apparatus that performs an etching process of semiconductor manufacturing. The fluid control device 1 includes a fluid inlet 2, an on-off valve 61, a fluid control valve 4, and a fluid outlet 5, each of which has the following configuration.

  2 is a fluid inlet made of PFA. The fluid inlet 2 communicates with the inlet flow path 72 of the on-off valve 61.

  As shown in FIG. 2, 4 is a fluid control valve that controls the fluid pressure in accordance with the operating pressure. The fluid control valve 4 includes a main body 12, a bonnet 13, a spring receiver 14, a piston 15, a spring 16, a first valve mechanism 17, a second valve mechanism 18, and a base plate 19.

  12 is a PTFE main body having a diameter larger than the diameter of the second gap 20 provided at the bottom center and opened to the bottom, and the second gap 20 provided open at the top at the top. The inlet channel 22 has one gap 21 and communicates with the second gap 20 on the side surface, and the outlet channel 23 communicates with the first gap 21 on the surface facing the inlet channel 22. In addition, a communication hole 24 that communicates the first gap 21 and the second gap 20 and has a diameter smaller than the diameter of the first gap 21 is provided. The upper surface portion of the second gap 20 is a valve seat 25. The outlet channel 23 communicates with the fluid outlet 5 described later.

  13 is a PVDF bonnet, in which a cylindrical gap 26 is provided, and a stepped portion 27 having a diameter larger than that of the gap 26 is provided on the inner peripheral surface of the lower end, so that compressed air is supplied to the inside of the gap 26 on the side surface. An air supply hole 28 that communicates between the air gap 26 and the outside, and a microhole discharge hole 29 for discharging a small amount of compressed air introduced from the air supply hole 28 are provided. The discharge hole 29 may not be provided if it is not necessary for supplying compressed air.

  14 is a flat circular spring receiver made of PVDF, which has a through hole 30 in the central portion thereof, and whose upper half is inserted into the stepped portion 27 of the bonnet 13. An annular groove 31 is provided in the side surface of the spring receiver 14, and an O-ring 32 is attached to prevent the compressed air from flowing out from the bonnet 13 to the outside.

  Reference numeral 15 denotes a PVDF piston, which has a disc-shaped flange 33 at the top, a piston shaft 34 that protrudes in a cylindrical shape from the center lower portion of the flange 33, and a female screw provided at the lower end of the piston shaft 34 It has the 1st junction part 35 which consists of a part. The piston shaft 34 is provided with a smaller diameter than the through hole 30 of the spring receiver 14, and the first joint portion 35 is joined to the second joint portion 40 of the first valve mechanism 17 described later by screwing.

  A SUS spring 16 is sandwiched between the lower end surface of the flange portion 33 of the piston 15 and the upper end surface of the spring receiver 14. As the piston 15 moves up and down, the spring 16 expands and contracts, but a long free length is preferably used so that the change in load at that time is small.

  Reference numeral 17 denotes a PTFE first valve mechanism, which includes a membrane portion 37 having a cylindrical portion 36 provided so as to protrude upward from the outer peripheral edge portion, a first diaphragm 38 having a thick portion at the center portion, A second joint 40 made of a small-diameter male screw provided at the upper end of the shaft 39 provided protruding from the central upper surface of one diaphragm 38, and a female formed at the lower end protruding from the central lower surface. It has the 3rd junction part 41 screwed together with the 4th junction part 45 of the postscript 2nd valve mechanism body 18 which consists of a thread part. The tubular portion 36 of the first diaphragm 38 is sandwiched and fixed between the main body 12 and the spring receiver 14 so that the first valve chamber 42 formed from the lower surface of the first diaphragm 38 is hermetically sealed. Yes. The upper surface of the first diaphragm 38 and the gap 26 of the bonnet 13 are sealed through an O-ring 32 to form an air chamber filled with compressed air supplied from the air supply hole 28 of the bonnet 13. .

  Reference numeral 18 denotes a PTFE second valve mechanism body, which is provided inside the second gap 20 of the main body 12 and provided with a diameter larger than the communication hole 24, and provided protruding from the upper end surface of the valve body 43. A shaft 44, a fourth joint 45 formed by a male threaded portion fixed by screwing with a third joint 41 provided at the upper end thereof, and a rod provided protruding from the lower end surface of the valve body 43 46 and a second diaphragm 48 having a cylindrical protrusion 47 that extends in the radial direction from the lower end surface of the rod 46 and protrudes downward from the peripheral edge. The cylindrical protrusion 47 of the second diaphragm 48 is sandwiched between a protrusion 50 of the base plate 19 and the main body 12, which will be described later, thereby forming a second gap 20 of the main body 12 and the second diaphragm 48. The second valve chamber 49 is sealed.

Reference numeral 19 denotes a PVDF base plate having a protrusion 50 for holding and fixing the cylindrical protrusion 47 of the second diaphragm 48 of the second valve mechanism 18 between the main body 12 at the upper center. A notch recess 51 is provided at the upper end portion, and a breathing hole 52 communicating with the notch recess 51 is provided on the side surface. The main body 12 is passed between the bonnet 13 and fixed with bolts and nuts (not shown). is doing. In this embodiment, the spring 16 is provided in the gap 26 of the bonnet 13 to urge the piston 15, the first valve mechanism 17 and the second valve mechanism 18 upward. A configuration may be adopted in which the piston 15, the first valve mechanism 17, and the second valve mechanism 18 are urged upward by being provided in the notch recess 51 of the base plate 19.
Reference numeral 5 denotes a PFA fluid outlet.

  As shown in FIG. 3, 61 is an on-off valve. The on-off valve 61 is formed by a main body 66, a drive unit 67, a piston 68, a diaphragm holder 69, and a valve body 70.

  A PTFE main body 66 has a valve chamber 71 at the center of the upper end in the axial direction, and an inlet channel 72 and an outlet channel 73 communicating with the valve chamber 71. The inlet channel 72 is a fluid inlet. The outlet channel 73 communicates with the flow rate measuring device 62. An annular groove 74 is provided outside the valve chamber 71 on the upper surface of the main body 66.

  A driving unit 67 made of PVDF is provided with a cylindrical cylinder portion 75 therein, and is fixed to the upper portion of the main body 66 with bolts and nuts (not shown). A pair of working fluid supply ports 76 and 77 communicated with the upper side and the lower side of the cylinder part 75 are provided on the side surface of the drive part 67.

  Reference numeral 68 denotes a PVDF piston, which is fitted in the cylinder portion 75 of the drive portion 67 so as to be sealed and movable up and down in the axial direction, and a rod portion 78 is suspended from the center of the bottom surface.

  Reference numeral 69 denotes a PVDF diaphragm presser, which has a through hole 79 through which the rod portion 78 of the piston 68 passes in the center, and is sandwiched between the main body 66 and the drive portion 67.

  Reference numeral 70 denotes a PTFE valve element accommodated in the valve chamber 71, and is screwed to the tip of the rod portion 78 of the piston 68 that penetrates the through hole 79 of the diaphragm retainer 69 and protrudes from the lower surface of the diaphragm retainer 69. It moves up and down in the axial direction in accordance with the vertical movement of the piston 68. The valve body 70 has a diaphragm 80 on the outer periphery, and the outer peripheral edge of the diaphragm 80 is fitted into the annular groove 74 of the main body 66 and is sandwiched between the diaphragm presser 69 and the main body 66.

  Next, the operation of the fluid control apparatus according to the first embodiment of the present invention will be described.

  The fluid that has flowed into the fluid inlet 2 of the fluid control device 1 first flows into the on-off valve 61. When the on-off valve 61 is in a closed state, the fluid is blocked by the on-off valve 61 and no fluid flows downstream from the on-off valve 61. Thereby, the maintenance of the fluid control valve 4 in the fluid control device 1 can be easily performed. In addition, when any trouble occurs in the flow path, the fluid can be urgently shut off by closing the on-off valve 61. For example, when the corrosive fluid leaks, the components in the semiconductor manufacturing apparatus are corroded. Can prevent secondary disasters. When the on-off valve 61 is in the open state, the fluid passes through the on-off valve 61 and flows into the fluid control valve 4, and is controlled to have a set flow rate by manual or open loop control by an operator or a control unit. The fluid flows out from the fluid outlet 5.

  Here, the operation of the on-off valve 61 will be described. When compressed air is injected as a working fluid from the outside through the working fluid supply port 77, the piston 68 is pushed up by the pressure of the compressed air, so that the rod portion 78 joined to the piston 68 is lifted upward, and the lower end of the rod portion 78. The valve body 70 joined to the portion is also lifted upward, and the valve is opened.

  On the other hand, when compressed air is injected from the working fluid supply port 76, as the piston 68 is pushed down, the rod portion 78 and the valve body 70 joined to the lower end thereof are also pushed down, and the valve is closed. It becomes.

  With the above operation, the fluid flowing into the fluid inlet 2 of the fluid control device 1 can easily perform maintenance or the like of the fluid control device 1 by closing the on-off valve 61, and the fluid can be shut off urgently. Can be performed.

  When the on-off valve 61 is open, the fluid that has flowed into the fluid inlet 2 of the fluid control device 1 first passes through the on-off valve 61 and then flows into the fluid control valve 4.

Here, the operation of the fluid control valve 4 with respect to the operating pressure of the control air supplied from the control air supply control device (not shown) will be described (see FIG. 2).
The operating pressure of the control air is controlled by manually or open-loop controlling the control air supply control device. The manual control is for controlling the fluid so that the fluid becomes the parameter target value (set flow rate or set pressure, etc.) while monitoring the parameters (eg, flow rate, pressure, etc.) representing the characteristics of the fluid. It means that the operation pressure of control air is controlled manually by operating an air supply control device or the like (not shown). In addition, the open loop control means that a relationship between an input signal (a parameter representing a characteristic of a fluid) and an output signal (an operation pressure of control air associated with the parameter target value) is previously mapped, and a measurement device ( An output signal is transmitted to the control air supply control device based on an input signal from a control signal (not shown) to automatically control the operating pressure of the control air.

  The valve body 43 of the second valve mechanism 18 includes the repulsive force of the spring 16 sandwiched between the flange portion 33 of the piston 15 and the spring receiver 14, and the fluid pressure on the lower surface of the first diaphragm 38 of the first valve mechanism 17. Due to this, a force for urging upward acts, and a force for urging downward by the pressure of the operation pressure on the upper surface of the first diaphragm 38 is exerted. More precisely, the lower surface of the valve body 43 and the upper surface of the second diaphragm 48 of the second valve mechanism 18 are subjected to fluid pressure, but their pressure receiving areas are substantially equal, so the force is almost offset. . Accordingly, the valve body 43 of the second valve mechanism 18 is stationary at a position where the above-described three forces are balanced.

  When the operating pressure supplied from the control air supply control device is increased, the force that pushes down the first diaphragm 38 increases, so that the valve body 43 of the second valve mechanism 18 and the valve seat 25 are formed. Since the opening area of the fluid control unit 53 increases, the pressure in the first valve chamber 42 can be increased. Conversely, when the operating pressure is decreased, the opening area of the fluid control unit 53 is decreased and the pressure is also decreased. Therefore, an arbitrary pressure can be set by adjusting the operation pressure.

  In this state, when the upstream fluid pressure increases, the pressure in the first valve chamber 42 increases instantaneously. Then, the force that the lower surface of the first diaphragm 38 receives from the fluid is greater than the force that the upper surface of the first diaphragm 38 receives from the compressed air due to the operating pressure, and the first diaphragm 38 moves upward. Accordingly, the position of the valve body 43 also moves upward, so that the opening area of the fluid control unit 53 formed between the valve seat 25 and the pressure in the first valve chamber 42 is reduced. Eventually, the position of the valve body 43 moves to a position where the three forces are balanced and stops. At this time, if the load of the spring 16 does not change significantly, the pressure inside the air gap 26, that is, the force received by the upper surface of the first diaphragm 38 is constant, so the pressure received by the lower surface of the first diaphragm 38 is substantially constant. Accordingly, the fluid pressure on the lower surface of the first diaphragm 38, that is, the pressure in the first valve chamber 42 is substantially the same as the original pressure before the upstream pressure increases.

  When the upstream fluid pressure decreases, the pressure in the first valve chamber 42 also decreases instantaneously. Then, the force that the lower surface of the first diaphragm 38 receives from the fluid is smaller than the force that the upper surface of the first diaphragm 38 receives from the compressed air due to the operating pressure, and the first diaphragm 38 moves downward. Accordingly, the position of the valve body 43 is also moved downward, so that the opening area of the fluid control unit 53 formed between the valve seat 25 and the fluid pressure in the first valve chamber 42 is increased. Eventually, the position of the valve body 43 moves to a position where the three forces are balanced and stops. Accordingly, the fluid pressure in the first valve chamber 42 is substantially the same as the original pressure, as in the case where the upstream pressure has increased.

  With the above operation, the fluid flowing into the fluid control device 1 is controlled to a fluid pressure set by manual or open loop control by an operator or a control unit (not shown). When the fluid pressure becomes constant, the fluid flow rate is also constant, and the fluid flows out of the fluid outlet 5 with the flow rate controlled. In addition, even if the upstream pressure of the fluid flowing into the fluid control device 1 fluctuates, the flow rate is independently maintained constant by the operation of the fluid control valve 4, and instantaneous pressure fluctuations such as pump pulsation occur. Also, the flow rate can be controlled stably.

  Hereinafter, a fluid control apparatus according to a second embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 4, 59 is a fluid control device installed in a semiconductor manufacturing apparatus for performing an etching process of semiconductor manufacturing. The fluid control device 59 includes a fluid inlet 60, an on-off valve 61, a fluid control valve 169, and a fluid outlet 64, each of which has the following configuration.

  As shown in FIG. 13, reference numeral 169 denotes a fluid control valve. The fluid control valve 169 includes a main body 170, a valve member 185, a first diaphragm 186, a second diaphragm 187, a third diaphragm 188, and a fourth diaphragm 189.

  The main body 170 includes a chamber 176 that is divided into a first pressurizing chamber 177, a second valve chamber 178, a first valve chamber 179, and a second pressurizing chamber 180, and a fluid flows into the chamber 176 from the outside. The inlet channel 194 and the outlet channel 201 for flowing out from the chamber 176 to the fluid outlet 64, and are divided into a main body D174, a main body C173, a main body B172, a main body A171, and a main body E175 from above. Are assembled together.

  Reference numeral 171 denotes a PTFE main body A located inside the main body 170. A flat circular step 190 is provided in the upper part, and the center of the step 190 has a diameter smaller than that of the step 190 and the lower first valve chamber. An opening 191 to be 183 is provided, and a lower planar step 192 having a planar circular shape having a diameter larger than the diameter of the opening 191 is continuously provided below the opening 191. An annular groove 193 is provided on the upper surface of the main body A171, that is, the peripheral edge of the stepped portion 190, and an inlet channel 194 communicating with the opening 191 of the main body A171 from the side surface is provided. The inlet channel 194 communicates with the on-off valve 61.

  Reference numeral 172 denotes a PTFE main body B which is engaged and fixed to the upper surface of the main body A 171. A flat circular stepped portion 195 is provided on the upper portion, and an upper second portion having a smaller diameter than the stepped portion 195 is provided at the center of the stepped portion 195. An opening 196 that becomes the valve chamber 182 is provided. An opening 197 having a diameter smaller than the diameter of the opening 196 and a planar circular lower step 198 having the same diameter as the step 190 of the main body A 171 are continuously provided below the opening 196. . A valve seat 199 is formed around the lower end of the opening 197. An annular groove 200 is provided at a position opposite to the annular groove 193 of the main body A 171 on the lower surface of the main body B 172, that is, the peripheral edge of the lower step 198, and is located on the opposite side of the inlet channel 194 of the main body A 171. An outlet channel 201 communicating with the opening 196 from the side surface of the main body B 172 is provided. The outlet channel 201 communicates with the fluid outlet 230.

  Reference numeral 173 denotes a PTFE main body C fitted and fixed to the upper portion of the main body B 172. The flat circular diaphragm chamber 202 penetrates the upper and lower end surfaces of the main body C 173 in the center and has an enlarged diameter at the upper portion, and the diaphragm chamber 202 and the outside. And an annular protrusion 204 fitted to the step portion 195 of the main body B 172 at the lower end surface is provided around the diaphragm chamber 202.

  Reference numeral 174 denotes a PTFE main body D located at the upper part of the main body C 173. The lower part of the main body D is provided with an air chamber 205. The air supply hole is provided through the upper surface in the center and introduces compressed air from the outside into the air chamber 205. 206 is provided. In addition, a microscopic discharge hole 229 provided through the side surface is provided. Note that the discharge hole 229 may not be provided if it is not necessary for supplying compressed air.

  175 is a PVDF main body E that is fitted and fixed to the bottom of the main body A 171. The central portion is provided with an opening 207 that opens to the upper surface and becomes the second pressurizing chamber 180. Is provided with an annular projection 208 fitted and fixed to the lower step 192 of the main body A171. Further, a small-diameter breathing hole 209 communicating with the opening portion 207 therefrom is provided on the side surface of the main body E175.

  The five main bodies A171, B172, C173, D174, and E175 constituting the main body 170 described above are clamped and fixed by bolts and nuts (not shown).

  Reference numeral 185 denotes a PTFE valve member extending in the radial direction from the thick portion 210 provided in the center in a bowl shape, the communication hole 211 provided through the thick portion 210, and the outer peripheral surface of the thick portion 210. A first thin film portion 186 having a circular thin film portion 212 that is provided and an annular rib portion 213 that protrudes vertically from the outer peripheral edge of the thin film portion 212, and an upper center of the first diaphragm portion 186. An inverted mortar-shaped valve body 214 and an upper rod 215 provided with an upper end projecting upward from the upper part of the valve body 214 and projecting downward from the center of the lower end surface of the thick part 210 having a substantially hemispherical shape. The lower rod 216 is provided, and the lower end portion is formed in a substantially hemispherical shape, and is integrally formed. An annular rib portion 213 provided at the outer peripheral edge of the first diaphragm portion 186 is fitted into both annular concave grooves 193 and 200 provided in the main body A 171 and the main body B 172, and is sandwiched and fixed between the main body A 171 and the main body B 172. . The space formed between the inclined surface of the valve body 214 and the peripheral edge of the lower end surface of the opening 197 of the main body B 172 is a fluid control unit 217.

  Reference numeral 187 denotes a second diaphragm portion made of PTFE, which has a cylindrical thick portion 218 at the center, a circular thin film portion 219 provided radially extending from the lower end surface of the thick portion 218, and a thin film portion 219. It has the annular seal part 220 provided in the outer peripheral edge part, and is formed integrally. Further, the annular seal portion 220 at the peripheral edge of the thin film portion 219 is sandwiched and fixed between the step 195 at the top of the main body B 172 and the annular protrusion 204 of the main body C 173. The pressure receiving area of the second diaphragm portion 187 needs to be provided smaller than that of the first diaphragm portion 186.

  Reference numeral 188 denotes a third diaphragm portion made of PTFE, which has the same shape as the second diaphragm portion 187, and is arranged upside down. The upper end surface of the thick portion 221 is in contact with the lower rod 216 of the valve member 185, and the annular seal portion 223 at the peripheral portion of the thin film portion 222 is the lower step 192 of the main body A171 and the annular protrusion 208 of the main body E175. It is clamped and fixed. Note that the pressure receiving area of the third diaphragm portion 188 needs to be smaller than that of the first diaphragm portion 186 as described above.

  Reference numeral 189 denotes a fourth diaphragm portion. A cylindrical rib 224 having an outer diameter substantially the same as that of the diaphragm chamber 202 of the main body C173 at the peripheral portion, a column portion 225 at the center, and an inner periphery of the lower end surface of the cylindrical rib 224 and a column shape It has a film part 226 that is connected to the outer periphery of the upper end surface of the part 225. The cylindrical rib 224 is fitted and fixed to the diaphragm chamber 202 of the main body C 173 and is sandwiched and fixed between the main body B 172 and the main body C 173, and the columnar portion 225 is movable up and down in the diaphragm chamber 202. Further, the thick part 218 of the second diaphragm part 187 is fitted to the lower part of the cylindrical part 225.

  Reference numerals 227 and 228 denote a PVDF spring receiver and a SUS spring disposed in the opening 207 of the main body E175. Both pressurize the third diaphragm portion 188 inward (upward in the figure).

  From above, the chamber 176 formed inside the main body by the above-described configurations is arranged from the top to the first pressurizing chamber 177, the first diaphragm 186, and the main body B172 formed from the fourth diaphragm 189 and the main body D174 air chamber 205. The second valve comprising both the lower second valve chamber 181 formed between the lower step portion 198 and the second diaphragm portion 187 and the upper second valve chamber 182 formed from the opening 196 of the main body B172. The upper first valve chamber formed by the lower first valve chamber 183 formed by the chamber 178, the third diaphragm portion 188, and the opening portion 191 of the main body A171, the first diaphragm portion 186, and the step portion 190 of the main body A171. A first valve chamber 179 made of 184, and a second pressurizing chamber 180 formed by the third diaphragm portion 188 and the opening portion 207 of the main body E175. Hunt. Since the other structure of the second embodiment is the same as that of the first embodiment, the description thereof is omitted.

  Next, the operation of the fluid control apparatus according to the second embodiment of the present invention will be described.

The fluid that has passed through the on-off valve 61 flows into the fluid control valve 169. In the case of open loop control, a control unit (not shown) outputs a flow rate signal from a flow rate measuring device (not shown) to an electropneumatic converter (not shown), and the electropneumatic converter operates accordingly. Pressure is supplied to the fluid control valve 169 to drive it. In the case of manual control, the operation pressure of the control air is manually controlled, and the operation pressure corresponding to the target flow rate is supplied to the fluid control valve 169 and driven.
The fluid flowing out from the fluid control valve 169 is controlled by the fluid control valve 169 so that the flow rate becomes a constant value at the set flow rate.

  Here, the action | operation of the fluid control valve 169 with respect to the operation pressure supplied from an electropneumatic converter is demonstrated based on FIG. 5 and FIG. The fluid that has flowed into the first valve chamber 179 from the inlet channel 194 of the main body A 171 of the fluid control valve 169 is reduced in pressure through the communication hole 211 of the valve member 185 and flows into the lower second valve chamber 181. Furthermore, when the fluid flows from the lower second valve chamber 181 through the fluid control unit 217 and into the upper second valve chamber 182, the fluid is decompressed again due to a pressure loss in the fluid control unit 217, and is discharged from the outlet channel 201 to the fluid outlet 64. Spill to Here, since the diameter of the communication hole 211 is sufficiently small, the flow rate flowing through the valve is determined by the pressure difference before and after the communication hole 211.

  At this time, when the force that each diaphragm portion 186, 187, 188 receives from the fluid is seen, the first diaphragm portion 186 is moved upwardly by the fluid pressure difference between the first valve chamber 179 and the lower second valve chamber 181. Diaphragm portion 187 receives an upward force due to the fluid pressure in upper second valve chamber 182, and third diaphragm portion 188 receives a downward force due to the fluid pressure in first valve chamber 179. Here, since the pressure receiving area of the first diaphragm portion 186 is sufficiently larger than the pressure receiving areas of the second diaphragm portion 187 and the third diaphragm portion 188, the force acting on the second and third diaphragm portions 187 and 188 is as follows. The force acting on the first diaphragm portion 186 can be almost ignored. Therefore, the force that the valve member 185 receives from the fluid is an upward force due to the fluid pressure difference in the first valve chamber 179 and the lower second valve chamber 181.

  Further, the valve member 185 is biased downward by the pressurizing means of the first pressurizing chamber 177 and simultaneously biased upward by the pressurizing means of the second pressurizing chamber 180. If the force of the pressurizing means in the first pressurizing chamber 177 is adjusted to be larger than the force of the pressurizing means in the second pressurizing chamber 180, the resultant force that the valve member 185 receives from each pressurizing means is a downward force. Become. Here, the pressurizing means of the first pressurizing chamber 177 is based on the operating pressure supplied from an electropneumatic converter (not shown), and the pressurizing means of the second pressurizing chamber 180 is the spring 228. This is due to the repulsive force.

  Accordingly, the valve member 185 is stabilized at a position where the downward resultant force by each pressurizing means and the upward force due to the fluid pressure difference in the first valve chamber 179 and the lower second valve chamber 181 are balanced. That is, the pressure in the lower second valve chamber 181 is independently adjusted by the opening area of the fluid control unit 217 so that the resultant force by each pressurizing means and the force by the fluid pressure difference are balanced. Therefore, the fluid pressure difference between the first valve chamber 179 and the lower second valve chamber 181 is constant, and the differential pressure before and after the communication hole 211 is kept constant, so that the flow rate through the valve is always kept constant. It is.

  Here, the fluid control valve 169 operates by balancing the resultant force of each pressurizing means acting on the valve member 185 and the force due to the pressure difference between the first valve chamber 179 and the lower second valve chamber 181. If the resultant force of each pressurizing means acting on 185 is adjusted and changed, the fluid pressure difference between the first valve chamber 179 and the lower second valve chamber 181 becomes a value corresponding thereto. That is, by adjusting the downward force by the pressurizing means of the first pressurizing chamber, that is, the operating pressure supplied from the electropneumatic converter, the differential pressure around the communication hole 211 can be changed and adjusted. The flow rate can be set to an arbitrary flow rate without disassembling the valve.

  Further, if the force by the pressurizing means in the first pressurizing chamber 177 is adjusted to be smaller than the force by the pressurizing means in the second pressurizing chamber 180, the resultant force acting on the valve member 185 is only upward, and the valve of the valve member 185 The body 214 is pressed against the valve seat 199 of the opening 197 of the main body B172, and the fluid can be shut off. That is, the fluid control valve 169 is in a closed state unless the operation pressure is applied by adjusting the electropneumatic converter.

  With the above operation, the fluid flowing into the fluid control device is controlled by the fluid control valve 169 so as to be constant at the set flow rate, and flows out at the fluid outlet 64. Furthermore, even if the upstream pressure or the downstream pressure of the fluid flowing into the fluid control device fluctuates, the flow rate is maintained independently by the operation of the fluid control valve 169, so that instantaneous pressure fluctuations such as pump pulsation occur. Even if it occurs, the flow rate can be controlled stably. Further, since the fluid control valve 169 is configured not to be affected by fluctuations in the back pressure, it can be suitably used in applications where the back pressure fluctuates. Further, since the fluid control valve 169 can be used as an on-off valve by adjusting the operation pressure, it is not necessary to connect a separate fluid shut-off valve. Since other operations of the second embodiment are the same as those of the first embodiment, description thereof is omitted.

It is a longitudinal cross-sectional view of the fluid control apparatus which shows the 1st Example of this invention. It is an enlarged view of the fluid control valve of FIG. It is an enlarged view of the on-off valve of FIG. It is a longitudinal cross-sectional view of the fluid control apparatus which shows the 2nd Example of this invention. It is an enlarged view of the fluid control valve of FIG. It is the same figure as FIG. 5 which added another display to FIG. It is a conceptual block diagram which shows the conventional control apparatus of a pure water flow rate. It is sectional drawing which shows the conventional manual control apparatus (pressure reducing valve).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluid control apparatus 2 Fluid inflow port 4 Fluid control valve 5 Fluid outflow port 59 Fluid control apparatus 61 On-off valve 169 Fluid control valve

Claims (4)

A fluid control valve that controls the pressure of the fluid by controlling the pressure of the control fluid;
A manual or open loop control type fluid control device comprising an on-off valve for opening or shutting off the fluid flow.   The fluid control apparatus according to claim 1, wherein the fluid control valve and the on-off valve are arranged in one base block. The fluid control valve
A first gap having a diameter larger than the diameter of the second gap provided at the center of the lower part, the second gap provided to the bottom, the inlet channel communicating with the second gap, and the upper face opened to the upper part. The second air gap, the outlet channel communicating with the first air gap, the communication hole having a diameter smaller than the diameter of the first air gap, the first air gap, and the second air gap. A main body having a valve seat on its upper surface, a bonnet having a cylindrical gap communicating with an air supply hole and a discharge hole provided on a side surface or an upper surface, and a stepped portion provided on a lower end inner peripheral surface; A spring receiver that is inserted into the step portion of the bonnet and has a through hole in the center portion, a first joint portion that is smaller in diameter than the through hole of the spring receiver at the lower end portion, and a flange portion is provided at the upper portion, inside the gap of the bonnet The piston is inserted in such a way that it can move up and down, and is supported by the lower end of the flange of the piston and the upper end of the spring support. The first diaphragm in which the central portion forming the first valve chamber is formed in such a manner that the spring and the peripheral edge portion are sandwiched and fixed between the main body and the spring receiver and cover the first gap of the main body. A second joint that is joined and fixed to the first joint of the piston through the through hole of the spring receiver at the center of the upper surface, and a third joint that is provided to penetrate the communication hole of the main body at the center of the lower surface. A first valve mechanism body, a valve body located inside the second gap of the main body and having a diameter larger than the communication hole of the main body, and a first valve mechanism body protruding from the upper end surface of the valve body. A second valve mechanism having a fourth joint that is joined and fixed to the three joints, a rod that protrudes from the lower end surface of the valve body, and a second diaphragm that extends in the radial direction from the lower end surface of the rod The body and the second diaphragm peripheral edge of the second valve mechanism located below the body are clamped and fixed between the body and the body. And a base plate having a notch recess at the upper center of the protrusion and a breathing hole communicating with the notch recess, and a second valve mechanism in accordance with the vertical movement of the piston. The fluid control device according to claim 1, wherein an opening area of a fluid control unit formed by the valve body and the valve seat of the main body is changed. The fluid control valve
A fluid inlet channel, an outlet channel, a main body formed from a chamber communicating with the inlet channel and the outlet channel, a valve member having a valve body and a first diaphragm, and a lower part and an upper part of the valve member; It has a second diaphragm part and a third diaphragm part that are located and have a smaller effective pressure receiving area than the first diaphragm part, and the outer peripheral part of each diaphragm part is fixed to the main body part in the chamber by the valve member and each diaphragm part. The chamber is divided into a first pressurizing chamber, a second valve chamber, a first valve chamber, and a second pressurizing chamber by each diaphragm portion, and the first pressurizing chamber is always in contact with the second diaphragm portion. Means for applying a constant inward force, the first valve chamber communicates with the inlet flow path, the second valve chamber has a valve seat corresponding to the valve body of the valve member, and the valve seat The first diaphragm located on the first diaphragm side A lower second valve chamber communicating with the first valve chamber through a communication hole provided in the diaphragm portion, and an upper second valve chamber located on the second diaphragm portion side and provided in communication with the outlet flow path. And a fluid control unit that controls the fluid pressure in the lower second valve chamber by changing the opening area between the valve body and the valve seat by the vertical movement of the valve member, and the second pressurization 3. The fluid control apparatus according to claim 1, wherein the chamber has means for constantly applying a constant force inward to the third diaphragm portion.

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