JP3203899U - Mixing valve - Google Patents

Abstract

In a mixing valve that mixes various types of fluids to prepare a mixed fluid, the device main body can be miniaturized and the internal flow path through which the fluid flows can be shortened to maintain the cleanliness of the fluid. Provide a valve. An inflow chamber 15a connected to a fluid inflow portion 14a into which a fluid flows, a mixing flow path portion 12 in which a fluid and another fluid are mixed, and an inflow chamber and a mixing flow path portion are connected to connect the fluid. A connection path 16a that circulates to the mixing flow path section, a valve seat section 18a formed in a connection opening on the inflow chamber side of the connection path, and a housing section 17a connected to the inflow chamber are formed in the base block 11 made of fluororesin. A valve body portion 20a including a diaphragm portion 21a that is formed and abuts against the valve seat portion by advancing and retreating driving to inflow and stop the inflow of the fluid into the mixing channel portion is accommodated in the accommodating portion. A sealing block 25a for sealing the accommodation opening 37a by screwing is provided. [Selection] Figure 4

Description

  The present invention relates to a mixing valve, and more particularly, to a mixing valve used for a portion that supplies a plurality of types of fluids simultaneously with mixing.

  For example, extremely high cleanliness is required for fluids such as chemicals for cleaning and etching of silicon wafers in semiconductor manufacturing and the like. Single-wafer cleaning is the mainstream. This is because by cleaning the silicon wafers one by one, a high cleaning effect can be obtained without receiving contamination from other cleaning objects. In the case of this method, pure water and chemicals corresponding to each operation stage are sequentially prepared and supplied to a silicon wafer to be cleaned. Then, in the preparation of sequential pure water and chemicals, it is preferable that the interval from the storage unit to the use unit is as short as possible from the point of cleanliness.

  Therefore, a mixing valve that mixes a plurality of types of fluid and supplies the mixed fluid has been proposed (see Patent Document 1, etc.). For example, the structure of the mixing valve disclosed in FIG. 5 of Patent Document 1 will be described with reference to the schematic schematic diagram of FIG. This mixing valve prepares a mixed fluid from a plurality of fluids immediately before the use portion of the mixed fluid, and the mixed fluid is supplied as it is.

  In the mixing valve 100 of FIG. 6, a concave portion is formed on each side portion of the base block 101 having a polygonal shape in the plan view (hexagonal in the drawing). The recesses are valve chambers 111, 112, 113, 114, 115, and 116. In the drawing, the base block 101 is cut out and displayed as a cross section. A mixing channel portion 102 is formed at the center of the base block 101, and each valve chamber 111, 112, 113, 114, 115, 116 and the mixing channel portion 102 are connected by connection paths 103, 104, 105, 106, 107, 108. Connected. In each valve chamber 111, 112, 113, 114, 115, 116, valve body portions 121, 122, which perform inflow of fluid to the individual connection paths 103, 104, 105, 106, 107, 108 and stop inflow, 123, 124, 125, 126 are provided. In the drawing, all the valve body parts 121, 122, 123, 124, 125, 126 are in a seated state, and the valve chambers 111, 112, 113, 114, 115, 11 are connected to the connection paths 103, 104, 105, 106, 107, Inflow to 108 is stopped. Reference numerals 131, 132, 133, 134, 135, 136 are inflow portions through which fluid flows into the individual valve chambers 111, 112, 113, 114, 115, 116. 115, 116 are formed at positions immediately above.

  One valve mechanism part for driving the valve body parts 121, 122, 123, 124, 125, 126 forward and backward is housed in the housing blocks 141, 142, 143, 144, 145, 146, respectively. The base block 101 is made of a fluororesin such as PTFE in consideration of corrosion resistance and chemical resistance. However, since the fluororesin has a higher viscoelasticity than other resin materials, deformation called a creep phenomenon is likely to occur. Therefore, the housing blocks 141, 142, 143, 144, 145, 146 cannot be directly fixed to the base block 101 using bolts. This is because even if a screw groove is formed on the base block 101 side, it is damaged. Therefore, when the accommodation blocks 141, 142, 143, 144, 145, 146 and the base block 101 are fixed, the vertical hole portion H is formed in the base block 101, and the nut member N is inserted into the vertical hole portion H. And the fixing bolt B which penetrates the inside of the accommodation blocks 141, 142, 143, 144, 145, 146 is fastened with the nut member N, and the accommodation blocks 141, 142, 143, 144, 145, 146 are fixed.

  As can be understood from the form of the mixing valve 100, the number of storage blocks, valve body portions, and valve chambers increases from the base block 101 to increase the types of fluid flowing into the storage blocks 141, 142, 143. 144, 145, and 146 have a greatly overhanging structure. Further, in the mixing valve 100, the valve chambers 111, 112, 113, 114, 115, 116 are formed at positions away from the center, so that the connection paths 103, 104, 105, 106, 107, 108 also become longer. Therefore, since the volume of the mixing valve 100 is increased, it is not easy to reduce the size.

  From a series of circumstances, in a mixing valve that prepares a mixed fluid by mixing many kinds of fluids, there is a need for a mixing valve that can maintain the cleanliness of the fluid by further reducing the channel length and shortening the flow path length. It was.

JP 2009-281476 A

  The present invention has been made in view of the above points, and in a mixing valve for preparing a mixed fluid by mixing various kinds of fluids, the apparatus main body is miniaturized and the internal flow path through which the fluid flows is shortened. A mixing valve capable of maintaining the cleanliness of a fluid is provided.

  That is, the device of claim 1 is an inflow chamber connected to a fluid inflow portion into which a fluid flows, a mixing channel portion in which the fluid and another fluid are mixed, the inflow chamber, and the mixing channel portion. A connection path for connecting the fluid to the mixing flow path part, a valve seat part formed in a connection opening part on the inflow chamber side of the connection path, and a housing part connected to the inflow chamber are fluorine. A valve body portion having a diaphragm portion that is formed in a base block made of resin and that abuts against the valve seat portion by advancing and retreating driving to flow in and stop the flow of the fluid into the mixing channel portion is provided in the housing portion. The mixing valve includes a sealing block that is accommodated and seals the accommodation opening of the accommodation portion by screwing.

  The invention according to claim 2 relates to the mixing valve according to claim 1, wherein the valve body part is driven forward and backward by the flow of pressurized gas.

  According to the mixing valve according to the first aspect of the present invention, an inflow chamber connected to a fluid inflow portion into which a fluid flows, a mixing channel portion in which the fluid and other fluid are mixed, the inflow chamber, and the mixed flow A connecting passage for connecting the passage portion to flow the fluid to the mixing passage portion, a valve seat portion formed in a connecting opening portion on the inflow chamber side of the connecting passage, and a housing connected to the inflow chamber The valve body portion having a diaphragm portion is formed in a base block made of a fluororesin and abuts against the valve seat portion by advancing and retreating driving to stop the inflow and inflow of the fluid into the mixing flow path portion. Since a sealing block that is housed in the housing portion and seals the housing opening of the housing portion by screwing is provided, it is possible to reduce the size of the apparatus body and shorten the internal flow path through which the fluid flows. Maintaining fluid cleanliness Can. In addition, it has excellent corrosion resistance and chemical resistance.

  According to the mixing valve of the second aspect of the invention, in the first aspect of the invention, the valve body portion is driven forward and backward by the inflow and outflow of pressurized gas, so that a quick response is realized without complicating the mechanism. The Further, it is suitable when a corrosive fluid is used as the fluid.

1 is an overall cross-sectional view of a mixing valve of the present invention. It is one 1st longitudinal cross-sectional view of a valve mechanism part. It is one 2nd longitudinal cross-sectional view of a valve mechanism part. It is the whole longitudinal cross-sectional view of a mixing valve. It is the schematic of the substrate processing apparatus incorporating the mixing valve of this invention. It is a schematic cross-sectional view of a conventional mixing valve.

  A mixing valve 10 shown as one embodiment of the present invention is mainly connected to a final end portion of a fluid conduit such as a semiconductor manufacturing factory or a semiconductor manufacturing apparatus. The mixing valve 10 is used in a portion where mixing and stopping of a plurality of types of fluids are performed, and the fluid after mixing is supplied to the use section as it is. The structure of the mixing valve 10 will be described with reference to the overall cross-sectional view of FIG. 1 and the partial vertical cross-sectional views of FIGS. 2 and 3. The mixing valve 10 is a hexagonal plate-like object in plan view, and can support mixing of a maximum of six types of fluids (mixed fluids). Therefore, valve mechanisms Va, Vb, Vc, Vd, Ve, and Vf for controlling the flow of fluid are installed in each side portion. Since each valve mechanism part has the same structure, “a”, “b”, “c”, “d”, “e”, and “f” are attached to distinguish from each other. Hereinafter, the structure of the valve mechanism portion Va will be described as a representative. The structure after the valve mechanism Vb is also the same.

  The base block 11 serving as the main body of the mixing valve 10 is provided with a fluid inflow portion 14a for fluid inflow. The fluid inflow portion 14a is connected to the inflow chamber 15a. A mixing channel portion 12 is formed at the center of the mixing valve 10 (see FIGS. 1 and 4). In the mixing flow path unit 12, a fluid (mixed fluid) and another fluid (other mixed fluid) are mixed. The inflow chamber 15a and the mixing channel portion 12 are connected by a connection path 16a. Therefore, the fluid that has flowed into the mixing valve 10 (base block 11) from the fluid inflow portion 14a reaches the mixing flow path portion 12 via the inflow chamber 15a and the connection path 16a. Then, the mixed fluid flows out from the mixing channel portion 12 to the outside of the mixing valve 10 (base block 11).

  The fluid supplied to the mixing valve 10 is ultrapure water, hydrofluoric acid, hydrogen peroxide water, aqueous ammonia, hydrochloric acid, a surfactant, and other various chemicals. Without being limited to these types of fluids, the fluid is selected as needed.

  Further, as understood from FIG. 2, the valve seat portion 18a is formed in the connection opening portion 13a on the inflow chamber 15a side of the connection path 16a. The accommodating portion 17a is connected to the inflow chamber 15a. The base block 11 is formed of a fluororesin such as PTFE (polytetrafluoroethylene) or PFA (tetrafluoroethylene / perfluoroalkoxyethylene copolymer, perfluoroalkoxyalkane, etc.). These fluororesins are excellent in corrosion resistance and chemical resistance. In the case of PTFE, the base block 11 is processed into a desired shape by cutting. In the case of PFA, the base block 11 can be melted and molded in addition to cutting. Therefore, the accommodating portion 17a, the inflow chamber 15a, and the connection path 16a are formed in this order from each side portion of the base block 11 toward the center. In the present embodiment, the base block 11 is formed by cutting.

  The valve body 20a is disposed in the inflow chamber 15a. The valve part 23a of the valve body part 20a contacts (seats) the valve seat part 18a. Therefore, the connection path 16a is closed by the valve portion 23a, and the inflow of the fluid into the mixing flow path portion 12 and the stop of the inflow are performed. Further, a drive unit 30a that drives the valve body portion 20a to advance and retreat (forward drive and backward drive) is accommodated in the accommodating portion 17a and connected to the valve body portion 20a. The valve body portion 20a is formed of a valve portion 23a, a diaphragm portion 21a (movable film portion), and a flange portion 22a (fixed edge portion). The valve body 20a of the embodiment is also formed of a fluororesin such as PTFE in the same manner as the base block 11 in consideration of corrosion resistance. When the diaphragm portion 21a receives the fluid pressure of the fluid, the advance / retreat position of the valve body portion 20a (valve portion 23a) can be changed in a timely manner. In particular, the diaphragm portion 21a effectively acts on accurate fluid pressure and flow rate control.

  The sealing block 25a is used for holding and fixing the valve body portion 20a and the drive portion 30a in the housing portion 17a. More specifically, the valve portion 23a of the valve body portion 20a is disposed at a predetermined position in the inflow chamber 15a, and at the same time, the inflow chamber 15a is closed by the diaphragm portion 21a and the flange portion 22a. And the flange part 22a is installed in the step part 28a of the innermost part of the accommodating part 17a. Next, the fixed block 24a is inserted into the accommodating portion 17a, and the flange portion 22a of the valve body portion 20a is sandwiched between the step portion 28a on the base block 11 side and the fixed block 24a. A breathing path 19a is formed in the base block 11 and the fixed block 24a, and air circulation on the back side (side not in contact with liquid) of the diaphragm portion 21a is ensured.

  Further, a fixed cylinder portion 26a for pushing the fixed block 24a toward the center side (mixing flow path portion 12 side) of the base block 11 is also mounted. In the figure, the fixed cylinder portion 26a abuts on the step portion 29a of the base block 11 and the step portion 39a of the fixed block 24a, and the fixed block 24a is fixed. After that, the fixed cylinder part 26a is pushed into the center side (mixing flow path part 12 side) of the base block 11, and the sealing block 25a is mounted for sealing the accommodation opening 37a.

  A female screw is formed in the housing opening 37a of the housing portion 17a, and a male screw is formed in the sealing block 25a. The sealing block 25a is fixed to the accommodation opening 37a by screwing. When the base block 11 is PTFE or the like, it is a material that is easily deformed by a creep phenomenon. However, since the accommodating opening 37a of the accommodating portion 17a is sufficiently large, when the sealing block 25a is screwed into the accommodating opening 37a, the fixing is completed. In the drawing, reference symbol Sa denotes a screwing portion between the accommodation opening 37a and the sealing block 25a.

  Next, details of the drive unit 30a will be described. The drive part 30a is formed of a shaft part 31a and a piston head part 32a, and the shaft part 31a of the drive part 30a and the valve part 23a of the valve body part 20a are connected and fixed via a tip part 33a. In this example, a screw groove is formed in the tip 33a and is screwed to the valve 23a. The shaft portion 31a of the drive unit 30a is inserted into the fixed block 24a and can be moved forward and backward.

  A holding recess 36a is formed in the sealing block 25a, and a biasing spring 55a is mounted between the piston head portion 32a of the drive unit 30a and the sealing block 25a (holding recess 36a). Therefore, the spring receiving surface 34a of the piston head 32a always receives the spring elastic biasing force of the biasing spring 55a. And the valve part 23a of the valve body part 20a is contact | abutted (seated) with respect to the valve seat part 18a through the piston head part 32a and the axial part 31a.

  Here, in order to make the valve part 23a of the valve body part 20a of FIG. 2 separate from the valve seat part 18a (separated state), the pressurized gas (working gas) passes through the first air port 51a and the accommodating part 17a. Flows into the piston space 35a. The pressure of the pressurized gas resists the urging force of the urging spring 55 a, so that the piston head 32 a moves away from the center side of the base block 11. Therefore, the urging spring 55a and the pressurized gas are included in the driving means 50a that drives the driving unit 30a. The fluid that has flowed into the mixing valve 10 (base block 11) from the fluid inflow portion 14a reaches the mixing flow path portion 12 via the inflow chamber 15a and the connection path 16a. Therefore, the fluid that has flowed through the valve mechanism other than the valve mechanism Va collides with the mixed flow path 12 to generate a mixed fluid, which is discharged from the mixing valve 10.

  On the contrary, as shown in the cross-sectional view of FIG. 3, in order to make the valve portion 23a of the valve body portion 20a abut on the valve seat portion 18a (sitting state), the pressurized gas through the first air port 51a Supply is stopped. Alternatively, the pressurized gas is supplied into the accommodating portion 17a (holding recess 36a) through the second air port 52a. At this time, due to the biasing force of the biasing spring 55a, the piston head portion 32a moves forward toward the center side of the base block 11, and the valve portion 23a of the valve body portion 20a contacts the valve seat portion 18a. In this way, the fluid that has flowed into the mixing valve 10 (base block 11) from the fluid inflow portion 14a stays in the inflow chamber 15a, and the outflow of the fluid to the connection path 16a side is stopped. Of course, when returning to the state of FIG. 2 and resuming the flow of the fluid, the pressurized gas is supplied through the first air port 51a as in the description of FIG.

  An appropriate hole portion is formed in the fixed cylinder portion 26a, and the pressurized gas can freely flow into and out of the piston space 35a. Moreover, packing p is mounted | worn in a required location in order to ensure airtightness. These packings are O-rings etc. which are formed from well-known durable materials, such as urethane rubber, NBR, HNBR, silicone rubber, and fluororesin rubber. As is clear from the above description, the valve mechanism portion Va is mounted in the housing portion 17a of the disclosed base block 11 and performs a forward / backward movement of the valve body portion 20a, and a seal that fixes each member. It is a member such as a block 25a.

  In the illustrated embodiment, the advance / retreat drive of the valve body portion 20a (sitting and leaving of the valve portion 23a) is performed by the inflow and outflow of pressurized gas, and thus can be operated remotely. When the pressurized gas flows in and out, the pressurized gas of a predetermined pressure or higher is supplied from the air regulator, and the supply and stop of the supply of the pressurized gas are performed through a device such as a solenoid valve. Therefore, a quick response can be realized without complicating the mechanism. In addition, metal parts or the like are not used in the base block 11. For this reason, it is suitable when a corrosive fluid is used as the mixed fluid.

  FIG. 4 is an overall longitudinal sectional view of the mixing valve 10. Regarding the flow of fluid (mixed fluid) and the state of switching, paying attention to the fluid flowing into the valve mechanism portion Va from the fluid inflow portion 14a and the fluid flowing into the valve mechanism portion Vd from the fluid inflow portion 14d. I will explain. The fluid flows into the inflow chamber 15a in the mixing valve 10 from the fluid inflow portion 14a. However, since the valve portion 23a of the valve body portion 20a is in contact (sitting) with the valve seat portion 18a, the fluid is retained in the inflow chamber 15a. That is, the supply of the fluid flowing in from the fluid inflow portion 14a to the mixing channel portion 12 is stopped.

  On the other hand, on the valve mechanism portion Vd side, the valve portion 23d of the valve body portion 20d is separated from the valve seat portion 18d (separated state). Therefore, the fluid that has flowed into the inflow chamber 15d from the fluid inflow portion 14d reaches the mixing channel portion 12 via the inflow chamber 15d and the connection path 16a as it is, and flows out of the mixing valve 10 from here. In this state, only one type of fluid is supplied. Next, on the valve mechanism part Va side, as shown in FIG. 2 described above, the drive part 30a is driven forward and backward by the inflow and outflow of pressurized gas, and the valve part of the valve body part 20a is driven similarly to the valve mechanism part Vd side in FIG. When 23a leaves | separates from the valve seat part 18a, the fluid which flowed in into the inflow chamber 15a from the fluid inflow part 14a reaches the mixing flow path part 12 via the inflow chamber 15a and the connection path 16a as it is (illustration omitted). If it does so, both fluids collide and mix in the mixing channel part 12, and it flows out out of the nozzle 12n of the mixing channel part 12 of the mixing valve 10 as a mixed fluid.

  In order to prevent leakage of fluid from the connection paths 16a and 16d and the mixing flow path section 12 during the forward / backward drive of the valve body section 20a through the drive section 30a and the forward / backward drive of the valve body section 20d through the drive section 30d, an appropriate sac is used. A back function is also provided in the valve body portions 20a and 20d.

  As understood from FIGS. 1 to 4, the number of fluids (mixed fluids) is two or more (six types in the drawing). Therefore, the fluid inflow portion, the inflow chamber, the connection path, the connection opening, the valve seat portion, the valve body portion, the drive portion, and the sealing block are all provided in the same number as the number of types of fluid. In this way, since the members other than the mixing channel portion are completely independent, inadvertent mixing of the fluid in the supply stop state is avoided. Therefore, the cleanliness of both the mixed fluid and the fluid in a non-mixed state is ensured, which greatly contributes to product quality. In addition, since the mixing valve of the present invention has a structure in which any valve mechanism part is accommodated in the base block, it can be downsized as a whole, and the length of the connection path connecting the inflow chamber and the mixing flow path part can be reduced. It is also formed short. Therefore, a decrease in cleanliness during the circulation of the fluid in the base block is also suppressed.

  Next, a specific usage example of the mixing valve 10 will be described. The schematic diagram of FIG. 5 is an example of a single wafer processing substrate processing apparatus that processes silicon wafers W one by one. The silicon wafer W is placed on the rotating disk of the spin chuck 1. A mixing valve 10 is disposed immediately above the silicon wafer W. In the mixing valve 10, a mixed fluid (including one kind of fluid) is supplied from the nozzle 12n to the silicon wafer W simultaneously with mixing of the flowing fluid. The fluid is stored in the supply units 9A, 9B, and 9C for each type, and is supplied to the mixing valve 10 through the fluid pipes 3A, 3B, and 3C corresponding to the respective supply units. The mixing valve 10 can handle up to six types of fluid supply. In the figure, only three types of piping are disclosed.

  A flow rate control valve 4 and a fluid flow rate detection unit 6 are connected to each of the fluid pipings 3A, 3B, and 3C. The flow control valve 4 is a constant flow valve that stabilizes the fluid supply by stabilizing the flow rate and fluid pressure of the downstream fluid. The flow rate detection unit 6 is a public flow rate sensor, a temperature sensor, and a concentration sensor, and the circulating fluid is monitored.

  The fluid is mixed uniformly as necessary in the mixing valve 10 to become a mixed fluid. The mixed fluid is discharged to the silicon wafer W from the nozzle 12n. In the case of cleaning, only hot water or cold water is discharged alone to the silicon wafer W. In the case of illustration, the supply and stop of the fluid and the fluid mixing in the mixing valve 10 are controlled by the arithmetic and control unit 5. The arithmetic control device 5 includes an arithmetic unit 7 and a control unit 8.

  The calculation unit 7 is a known calculation device such as a microcomputer or a PLC (programmable logic controller). A signal for controlling the flow rate of the flow rate control valve 4 is generated in accordance with an instruction from the outside or a change in the measured flow rate value of the controlled fluid detected by the flow rate detection unit 6. The control unit 8 is an electropneumatic converter that supplies pressurized gas adjusted to a predetermined pressure necessary for the drive unit of the valve body in each flow control valve 4. When the drive unit of the flow control valve 4 is a stepping motor, a servo motor or the like, a pulse transmitter, a controller, a driver, or the like necessary for driving the flow control valve 4 is used. The flow control valve 4 and the flow rate detection unit 6 are connected to the calculation control device 5 (the calculation unit 7 and the control unit 8) by a signal line sg. The signal line sg includes electrical signal wiring and pressurized gas supply piping. In the illustrated example, a pressurized gas supply pipe is connected to the mixing valve 10 as a signal line sg with the arithmetic control device 5.

  The field of use of the mixing valve of the present invention is not limited to the semiconductor manufacturing field described above. For example, it is also used in fields such as fluid mixing devices in the chemical industry and pharmaceutical manufacturing, biomedical devices for mixing drugs, and fuel supply control devices.

  In the mixing valve of the present invention, members related to the driving of the valve body portion can be collectively accommodated in the base block and can be stably fixed. This facilitates downsizing of the entire apparatus and shortens the internal flow path, which is convenient for maintaining the cleanliness of the fluid. Therefore, in complex mixing with an increased number of fluid types, it is possible to contribute to reducing fluid waste and stabilizing the quality of the mixed fluid.

DESCRIPTION OF SYMBOLS 10 Mixing valve 11 Base block 12 Mixing flow path part 13a Connection opening part 14a Fluid inflow part 15a Inflow chamber 16a Connection path 17a Storage part 18a Valve seat part 20a Valve body part 21a Diaphragm part 22a Flange part 23a Valve part 24a Fixing block 25a Sealing Stop block 26a Fixed cylinder part 30a Drive part 31a Shaft part 32a Piston head part 35a Piston space 37a Housing opening part 50a Drive means 51a First air port 52a Second air port 55a Energizing spring Sa Screw groove part Va, Vb, Vc, Vd, Ve , Vf Valve mechanism part p Packing 1 Spin chuck 3A, 3B, 3C Fluid piping 4 Flow rate control valve 5 Control device 6 Flow rate detection part 7 Calculation part 8 Control part 9A, 9B, 9C Supply part W Silicon wafer

Claims (2)

An inflow chamber connected to a fluid inflow section into which a fluid flows; and
A mixing channel part in which the fluid and other fluid are mixed;
A connection path for connecting the inflow chamber and the mixing flow path section to flow the fluid to the mixing flow path section;
A valve seat formed in a connection opening on the inflow chamber side of the connection path;
A housing portion connected to the inflow chamber is formed in a base block made of fluororesin,
A valve body portion having a diaphragm portion that is brought into contact with the valve seat portion by advancing and retreating driving to stop the inflow and inflow of the fluid into the mixing channel portion is housed in the housing portion.
A mixing valve comprising: a sealing block that seals the housing opening of the housing by screwing.   The mixing valve according to claim 1, wherein the valve body part is driven forward and backward by inflow and inflow of pressurized gas.

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