Patent Publication Number: US-2022213965-A1

Title: Valve device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation application under 35 U.S.C. § 120 of PCT/JP2020/033936, filed Sep. 8, 2020, which is incorporated herein by reference and which claimed priority to Japanese Application No. 2019-177873, filed Sep. 27, 2019. The present application likewise claims priority under 35 U.S.C. § 119 to Japanese Application No. 2019-177873, filed Sep. 27, 2019, the entire content of which is also incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates a valve device for use in a semiconductor manufacturing device etc. 
     BACKGROUND 
     Japanese Patent Application Publication No.H08-5115853 proposes a valve device that has a valve body formed with a first side groove as a gas inlet path and a second side groove as a gas outlet path. The first side groove is configured so that its diameter is enlarged near the valve chamber. 
     SUMMARY 
     In order to increase the gas flow path, the diameter of the first side groove may be enlarged near the valve chamber as in the valve device of Japanese Patent Application Publication No. 2003-014155, but the flow rate cannot be sufficiently increased only by this configuration. 
     Therefore, one of the objects of the present disclosure is to provide a valve device having a body that is capable of achieving a large flow rate. 
     A valve device according to one or more embodiments of the present disclosure includes: a body that is formed with a valve chamber, a first inflow passage, a second inflow passage, an outflow passage, and an annular groove and is provided with a valve seat; and a diaphragm that is configured to communicate with and interrupt the second inflow passage and the outflow passage by abutting the valve seat and separating from the valve seat. An end portion of the second inflow passage is open to the valve chamber. The valve seat is provided on a peripheral edge of a location where the valve chamber and the second inflow passage communicate with each other. The annular groove is open to the valve chamber and is formed around the second inflow passage. An end portion of the outflow passage is open to the annular groove. The first inflow passage has a plurality of flow passages including an inflow port and a plurality of outflow ports, and each outflow port is open to the annular groove. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a cross-sectional view of a valve device in an open state according to an embodiment; 
         FIG. 2  is a cross-sectional view of a body taken along a line II-II of  FIG. 1 ; and 
         FIG. 3  is a cross-sectional view of the body according to the modification. 
     
    
    
     DETAILED DESCRIPTION 
     A valve device according to an embodiment of the present disclosure will be described with reference to the drawings. 
       FIG. 1  is a cross-sectional view of a valve device  1  according to the present embodiment.  FIG. 2  is a cross-sectional view of a body  11  taken along a line II-II of  FIG. 1 . 
     As illustrated in  FIG. 1 , the valve device  1  includes a body portion  10 , an actuator  20 . The valve device  1  according to the present embodiment is a so-called three-way valve device. In the following description, the side of the actuator  20  of the valve device  1  is defined as the upper side, and the side of the body portion  10  is defined as the lower side. 
     Body Portion  10   
     The body portion  10  includes the body  11 , a seat  12  serving as a valve seat, a bonnet  13 , a diaphragm  14 , a retainer adapter  15 , a diaphragm retainer  16 , a holder  17 , and a compression coil spring  18 . 
     The body  11  is a substantially cube and has a first surface  11 A which is an upper surface, a second surface  11 B which is a lower surface, and a third surface  11 C and a fourth surface  11 D which are side surfaces and face each other. The body  11  is formed with a valve chamber  11   e,  a first inflow passage  11   f,  a second inflow passage  11   g,  an outflow passage  11   h , and an annular groove  11   i.    
     The valve chamber  11   e  is formed so as to open toward the first surface  11 A. The second inflow passage  11   g  has a substantially inverted L shape in  FIG. 1 , one end thereof opens to the third surface  11 C, and the other end opens to the valve chamber  11   e.  The resin seat  12  is formed in an annular shape, and is provided in the body  11  on the peripheral edge of a location where the valve chamber  11   a  and the second inflow passage  11   g  communicate with each other. 
     The annular groove  11   i  is open at the upper end to the valve chamber  11   e  and is formed around a portion of the second inflow passage  11   g  extending in the vertical direction. The outflow passage  11   h  is open at one end to the annular groove  11   i  and at the other end to the fourth surface  11 D. The outflow passage  11   h  is located on the opposite side to the first inflow passage  11   f  so as to sandwich the portion of the second inflow passage  11   g  extending in the vertical direction. A pipe  2  is connected to a portion of the fourth surface  11 D of the body  11  corresponding to the other end of the outflow passage  11   h.    
     The first inflow passage  11   f  is located above the portion of the second inflow passage  11   g  extending in the horizontal direction (left-right direction in  FIG. 1 ). As shown in  FIG. 2 , the first inflow passage  11   f  has a plurality of flow passages including one inflow port  11   j  and a plurality of outflow ports  11   k,  and each outflow port  11   k  opens to the annular groove  11   i.  In the present embodiment, the first inflow passage  11   f  is constituted by one inflow port  11   j  and two outflow ports  11   k.  That is, the first inflow passage  11   f  is branched into two flow passages. The body  11  has a branch portion  11 L located between the inflow port  11   j  of the first inflow passage  11   f  and a central axis C of the annular groove  11   i.  The first inflow passage  11   f  is branched into two flow passages by the branch portion  11 L. The branch portion  11 L has a substantially isosceles triangle shape in a plan view. 
     The inflow port  11   j  of the first inflow passage  11   f  is open to the third surface  11 C. Therefore, one end of the second inflow passage  11   g  and the inflow port  11   j  of the first inflow passage  11   f  are open to the same surface. The diameter (opening area) of the inflow port  11   j  of the first inflow passage  11   f  is smaller than the diameter (opening area) of one end (inflow port) of the second inflow passage  11   g.  That is, the diameter of the inflow port  11   j  of the first inflow passage  11   f  and the diameter of one end (inflow port) of the second inflow passage  11   g  are different from each other. The cross-sectional area of the first inflow passage  11   f  increases from the inflow port  11   j  toward the annular groove  11   i.    
     As shown in  FIG. 1 , the bonnet  13  has a substantially cylindrical shape with a lid, and is fixed to the body  11  so as to cover the valve chamber  11  e by screwing the lower end portion thereof into the body  11 . 
     The diaphragm  14 , which serves as a valve element, is held by pinching an outer peripheral edge portion thereof between the retainer adapter  15 , which is disposed on a lower end of the bonnet  13 , and a bottom surface forming the valve chamber  11   e  of the body  11 . The fluid passage is opened and closed by causing the diaphragm  14  to separate from and abut (press against) the seat  12 . 
     The diaphragm retainer  16  is provided on the upper side of the diaphragm  14 , and configured to be capable of pressing the center portion of the diaphragm  14 . The diaphragm retainer  16  is fitted to the holder  17 . 
     The holder  17  has a substantially columnar shape, and is disposed in the bonnet  13  so as to be movable up and down. The stem  25 , described later, is screwed to the upper portion of the holder  17 . 
     The compression coil spring  18  is provided inside the bonnet  13  so as to bias the holder  17  downward at all times. Therefore, the valve device  1  is held in the closed state normally (when the actuator  20  is not driven) by the compression coil spring  18 . 
     Actuator  20   
     The actuator  20  is an air-driven actuator and has a substantially columnar overall shape, and includes a casing  21 , a partition disk  22 , a first piston  23 , a second piston  24 , and a stem  25 . 
     The casing  21  has a lower casing  21 A and an upper casing  21 B having a lower end portion of which is screwed to an upper end portion of the lower casing  21 A. The lower casing  21 A has a substantially stepped cylindrical shape. An outer periphery of a lower end portion of the lower casing  21 A is screwed to the inner periphery of a through hole in the bonnet  13 . The upper casing  21 B has a substantially cylindrical shape with a lid. A fluid introduction passage  21   c  is formed in an upper end portion of the upper casing  21 B. 
     A nut  26  is screwed to the outer periphery of the lower end portion of the lower casing  21 A. The nut  26  abuts the bonnet  13  so as to suppress rotation of the lower casing  21 A relative to the bonnet  13 . 
     The partition disk  22  has a substantially disk-shape and is provided immovably inside the casing  21 . The stem  25  penetrates a center portion of the partition disk  22 . 
     The first piston  23  has a substantially disk-shape. The stem  25  penetrates a center portion of the first piston  23 . A first pressure chamber P 1  is formed by the lower casing  21 A and the first piston  23 . 
     The second piston  24  has a substantially disk-shape. The stem  25  penetrates a center portion of the second piston  24 . A second pressure chamber P 2  is formed by the second piston  24 , the partition disk  22 , and the upper casing  21 B. 
     The stem  25  has a substantially columnar shape, and is provided so as to be movable in the up-down direction. A lower end portion of the stem  25  is screwed to the holder  17 . 
     A fluid flow passage  25   a  that extends in the up-down direction is formed in an upper half of the stem  25 . Further, first and second fluid outflow holes  25   b  and  25   c  that cross the fluid flow passage  25   a  are formed in the upper half of the stem  25 . An upper end of the fluid flow passage  25   a  opens in an upper surface of the stem  25 . The first fluid outflow hole  25   b  communicates with the first pressure chamber P 1 . The second fluid outflow hole  25   c  is positioned above the first fluid outflow hole  25   b,  and communicates with the second pressure chamber P 2 . 
     The stem  25  includes a plurality of stepped portions, and the stepped portions are in contact with an upper surface of the first piston  23  and an upper surface of the second piston  24 . Consequently, the stem  25  and the holder  17  are moved upward when the first piston  23  and the second piston  24  are moved upward. 
     Opening/closing Operation of Valve Device  1   
     Next, an opening/closing operation of the valve device  1  according to the present embodiment will be described. 
     In the valve device  1  according to the present embodiment, in a state where no drive fluid flows into the first and second pressure chambers P 1  and P 2 , the holder  17  and the stem  25  are held at bottom dead center (close to the body  11 ) by the biasing force of the compression coil spring  18 , the diaphragm  14  is retained by the diaphragm retainer  16 , and the lower surface of the diaphragm  14  is pressed against the seat  12 , whereby the valve device  1  is in a closed state. In other words, in a normal state (a state where no drive fluid is supplied), the valve device  1  is in a closed state. 
     A state in which drive fluid flows into the valve device  1  from a drive fluid supply source, is then established. As a result, the drive fluid is supplied to the valve device  1 . The drive fluid passes through the fluid introduction passage  21   c,  the fluid flow passage  25   a,  and the first and second fluid outflow holes  25   b  and  25   c  by via an air tube and a pipe joint, not shown in the figures, then flows into the first and second pressure chambers P 1  and P 2 . Thus, the first and second pistons  23  and  24  rise against the biasing force of the compression coil spring  18 . Consequently, the holder  17  and the stem  25  move to top dead center, thereby separating from the body  11 , and the diaphragm  14  is moved upward by elastic force thereof and the pressure of the fluid (gas), thereby communicating the second inflow passage  11   g  and the outflow passage  11   h  through the annular groove  11   i.  As a result, the valve device  1  enters an open state. 
     To bring the valve device  1  from the open state to the closed state, a three-way valve, not shown in the figures, is switched to a flow for discharging the drive fluid to the outside from the actuator  20  (first and second pressure chambers P 1  and P 2 ) of the valve device  1 . Consequently, the drive fluid in the first and second pressure chambers P 1  and P 2  is discharged to the outside through the first and second fluid outflow holes  25   b  and  25   c,  the fluid flow passage  25   a,  and the fluid introduction passage  21   c.  Accordingly, the holder  17  and the stem  25  are moved to bottom dead center by the biasing force of the compression coil spring  18 , and as a result, the valve device  1  enters the closed state. 
     The first inflow passage  11   f  is constantly communicates with the outflow passage  11   h  through the annular groove  11   i.  For example, the valve device  1  is closed to allow fluid (gas) to flow into the first inflow passage  11   f  from a fluid supply source not shown in the figure. As a result, the fluid (gas) is supplied to the valve device  1 , and the fluid (gas) that flows into the inflow port  11   j  of the first inflow passage  11   f  branches at the branch portion  11 L, flows to the annular groove  11   i  through the two outflow ports  11   k,  and flows out from the outflow passage  11   h.  The fluid (gas) supplied to the first inflow passage  11   f  may be different from or the same as the fluid (gas) supplied to the second inflow passage  11   g.    
     According to the valve device  1  of the present embodiment described above, the first inflow passage  11   f  has the plurality of flow passages including one inflow port  11   j  and a plurality of outflow ports  11   k,  and each outflow port  11   k  opens to an annular groove  11   i.  With this configuration, the cross-sectional area of the flow passage on the primary side of the valve device  1  can be increased, so that the flow rate of the fluid (gas) flowing through the valve device  1  can be increased. Therefore, it is possible to provide the valve device  1  having the body  11  that is capable of achieving a large flow rate. 
     The body  11  has the branch portion  11 L that is located between the inflow port  11   j  and the central axis C of the annular groove  11   i  and that branches the first inflow passage  11   f  into the plurality of flow passages. Therefore, the fluid flowing into the first inflow passage  11   f  flows into the annular groove  11   i  without any disturbance. Accordingly, the flow rate of the fluid (gas) flowing through the valve device  1  can be increased. 
     The inflow port  11   j  of the first inflow passage  11   f  and the inflow port of the second inflow passage  11   g  are open on the same surface (the third surface  11 C) of the body  11 , and the diameters of the inflow ports are different from each other. For example, even if the diameter of the inflow port  11   j  of the first inflow passage  11   f  is smaller than the diameter of the inflow port of the second inflow passage  11   g,  the first inflow passage  11   f  is configured as described above, so that the cross-sectional area of the flow passage on the primary side of the valve device  1  can be increased, and the flow rate of the fluid (gas) flowing through the valve device  1  can be increased. 
     Since the cross-sectional area of the first inflow passage  11   f  increases from the inflow port  11   j  toward the annular groove  11   i,  the cross-sectional area of the flow passage on the primary side of the valve device  1  can be increased, and the flow rate of the fluid (gas) through the valve device  1  can be increased. 
     The present disclosure is not limited to the embodiment discussed above. A person skilled in the art could make a variety of additions, modifications, etc., within the scope of the present disclosure. 
     As shown in  FIG. 3 , the inflow port  11   j  of the first inflow passage  11   f,  one end of the second inflow passage  11   g,  and the other end of the outflow passage  11   h  may be configured to open to the second surface  11 B. Then, as shown in  FIG. 3 , the first inflow passage  11   f  may be configured to be inclined with respect to the central axis of the annular groove  11   i.    
     The first inflow passage  11   f  of the above embodiment is branched into two flow passages in a plan view as shown in  FIG. 2 , but may be branched into two flow passages in a side view. The first inflow passage  11   f  may be branched into a plurality of flow paths regardless of the plan view and the side view. The shape of the branch portion  11 L is not limited to the shape of the above embodiment, and may be any shape as long as it does not disturb the fluid flow.