Fluid control valve, fluid control device, and method for manufacturing orifice

Abstract

The present invention achieves a large flow rate for a fluid control valve without increasing the size of an orifice or an actuator. The present invention is provided with: an orifice 31 having a valve seat surface 31s; and a valve body 32 having a seating surface 32s to be seated on the valve seat surface 31s, wherein the orifice 31 has a plurality of inlets 31i and a plurality of outlets 31o which are open in the valve seat surface 31s in a first direction, and the plurality of inlets 31i and the plurality of outlets 31o are disposed side by side in a second direction crossing the first direction.

Description

Fluid control valve, fluid control device, and method for manufacturing orifice

[0001] The present invention relates to a fluid control valve, a fluid control device using the fluid control valve, and a method for manufacturing an orifice used in the fluid control valve.

[0002] Conventionally, there has been a demand for a larger flow rate in fluid control valves, and as shown in Patent Document 1, for example, improvements have been made to the structure of a valve seat member (orifice) having a valve seat surface.

[0003] Specifically, annular grooves each having a plurality of inlets and annular grooves each having a plurality of outlets are alternately formed concentrically on the valve seat surface of the valve seat member. In this fluid control valve, the valve seat member is formed with a plurality of inlets and a plurality of outlets, and the grooves each having inlets and the grooves each having outlets are alternately formed, thereby reducing pressure loss from the plurality of inlets to the plurality of outlets and enabling a large flow rate of fluid to flow.

[0004] JP 2010-230159 A

[0005] However, there is a limit to how much larger the flow rate can be achieved by forming multiple annular grooves on a valve seat surface of limited size and forming multiple inlets and multiple outlets within those grooves. Therefore, in order to achieve a larger flow rate using a conventional orifice, it is necessary to increase the size of the orifice itself or the actuator to increase the stroke of the valve disc.

[0006] Therefore, the present invention has been made in consideration of the above-mentioned problems, and its main object is to increase the flow rate of a fluid control valve without increasing the size of the orifice or actuator.

[0007] That is, the fluid control valve according to the present invention comprises an orifice having a valve seat surface, and a valve body having a seat surface that seats on the valve seat surface, the orifice having a plurality of inlets and a plurality of outlets that open along a first direction on the valve seat surface, and the plurality of inlets and the plurality of outlets are arranged side by side in a second direction that intersects the first direction.

[0008] In such a fluid control valve, a plurality of inlets and a plurality of outlets that open along a first direction are arranged side by side in a second direction that intersects the first direction, so that the boundary surface between the inlets and the outlets can be made longer than in a conventional orifice having a concentric groove, reducing pressure loss and allowing a large flow rate of fluid to flow. As a result, the flow rate of the fluid control valve can be increased without increasing the size of the orifice or actuator.

[0009] In order to further lengthen the boundary surface between the inlets and the outlets, it is preferable that the plurality of inlets and the plurality of outlets are arranged alternately in the second direction.

[0010] In addition, in order to further lengthen the boundary surface between the inlet and the outlet, it is desirable that the plurality of inlet and outlet ports are formed along the first direction from one end to the other end of the outer periphery of the valve seat surface.

[0011] In a specific embodiment of the orifice, the orifice has a first internal flow path that opens to the valve seat surface and an opposing surface that faces the valve seat surface, and a second internal flow path that opens to the valve seat surface and an outer circumferential surface between the valve seat surface and the opposing surface, and it is desirable that the first internal flow path communicates with one of the inlet or the outlet, and the second internal flow path communicates with the other of the inlet or the outlet.

[0012] It is desirable that a plurality of the second internal flow paths are formed corresponding to the other of the plurality of inlets or the plurality of outlets. With this configuration, the second internal flow path can be shaped along the first direction, that is, extending in one axial direction. For example, when the second internal flow path is configured as a flow path on the outflow side (downstream), the outflow direction of the fluid can be determined, and pressure loss can be reduced.

[0013] As a specific embodiment of the second internal flow path, it is desirable that the second internal flow path is formed so as to penetrate the orifice along the first direction.

[0014] As a specific embodiment of the first internal flow path, it is desirable that the first internal flow path has a confluence flow path that opens to the opposing surface and a plurality of branch flow paths that branch from the confluence flow path and open to the valve seat surface, and each of the plurality of branch flow paths is in communication with one of the plurality of inlets or the plurality of outlets. With this configuration, since the first internal flow path has a confluence flow path, it is possible to reduce pressure loss when a large flow rate is flowing.

[0015] It is desirable that the second internal flow path be formed within a side wall that forms each of the plurality of branch flow paths. With this configuration, the confluence flow path of the first internal flow path is not restricted by the second internal flow path, so that the flow path volume of the confluence flow path can be increased and pressure loss can be reduced when a large flow rate is flowed.

[0016] In a configuration in which the valve element moves relative to the valve seat surface of the orifice, a dead space may be formed around the valve seat surface. In order to allow the fluid flowing in this dead space to flow out without stagnation, it is desirable that the orifice have one or more outer internal flow paths, one end of which opens around the valve seat surface and the other end of which opens to the outer circumferential surface or the opposing surface.

[0017] Furthermore, the fluid control device according to the present invention is characterized by comprising the above-described fluid control valve, a flow sensor that measures the flow rate of the flow path, and a control unit that controls the fluid control valve based on the measurement value of the flow sensor.

[0018] Furthermore, the method for manufacturing an orifice according to the present invention is a method for manufacturing an orifice having a valve seat surface on which a valve element of a fluid control valve is seated, and is characterized in that a plurality of inlets and a plurality of outlets that open along a first direction are formed on the valve seat surface of the orifice, and the plurality of inlets and the plurality of outlets are formed alternately arranged in a second direction that intersects the first direction.

[0019] According to the present invention as described above, it is possible to increase the flow rate of a fluid control valve without increasing the size of the orifice or actuator.

[0020] 1 is a diagram schematically illustrating the configuration of a fluid control device according to one embodiment of the present invention. FIG. 1 is a partially enlarged cross-sectional view showing an orifice and a valve body of a fluid control valve according to the embodiment. FIG. 2 is a perspective view of the orifice according to the embodiment. FIG. 3 is a plan view of the orifice according to the embodiment. FIG. 4 is a cross-sectional view of the orifice according to the embodiment along line A-A. FIG. 5 is a schematic diagram showing (a) a valve seat surface, (b) an inlet, and (c) an outlet of the orifice according to the embodiment. FIG. 6 is a simulation result showing the boundary surface length vs. flow rate of the orifice according to the embodiment (this embodiment) and a conventional orifice (prior art). FIG. 7 is a diagram showing the arrangement angle of the orifice according to the embodiment, and (b) a simulation result showing the flow rate depending on the arrangement angle. FIG. 8 is a perspective view of an orifice according to a modified embodiment. FIG. 9 is a plan view of the orifice according to the modified embodiment. FIG. 10 is a cross-sectional view of the orifice according to the modified embodiment along line B-B. FIG. 11 is a simulation result showing the opening-flow rate characteristics of the orifice according to the modified embodiment (this embodiment) and a conventional orifice (prior art). FIG. 12 is a diagram schematically illustrating the configuration of a fluid control device according to a modified embodiment.

[0021] A fluid control device according to an embodiment of the present invention will be described below with reference to the drawings. Note that in all of the drawings shown below, parts are appropriately omitted or exaggerated for clarity. Identical components are assigned the same reference numerals, and descriptions thereof will be omitted as appropriate.

[0022] <Device Configuration> The fluid control device 100 of this embodiment is a so-called mass flow controller, and is used to control the flow rate of gas supplied to a chamber in which a semiconductor manufacturing process is performed, for example. Note that the fluid control device 100 may control not only gas but also liquid.

[0023] Specifically, as shown in FIG. 1, the fluid control device 100 includes a flow path block 2 having a flow path R formed therein, a fluid control valve 3 for controlling the gas in the flow path R, a flow sensor 4 for measuring the flow rate of the flow path R, and a control unit 5 for controlling the fluid control valve 3 based on the measurement value measured by the flow sensor 4.

[0024] The flow path block 2 is formed with an accommodating recess 21 in which the fluid control valve 3 is attached. The accommodating recess 21 is formed on one surface (the upper surface in FIG. 1 ) of the flow path block 2. An upstream flow path R1 is connected to the bottom surface of the accommodating recess 21, and a downstream flow path R2 is connected to the inner circumferential surface of the accommodating recess 21. In other words, the flow path R formed in the flow path block 2 is divided by the accommodating recess 21 into the upstream flow path R1 and the downstream flow path R2.

[0025] A gas inlet port (not shown) is provided at the upstream end of the upstream flow path R1, and a gas outlet port (not shown) is provided at the downstream end of the downstream flow path R2.

[0026] The fluid control valve 3 is a so-called normally open valve, and the opening degree thereof is controlled by an applied voltage. Note that the fluid control valve 3 may also be a so-called normally closed valve.

[0027] Specifically, as shown in FIGS. 1 and 2, the fluid control valve 3 includes an orifice (valve seat member) 31 having a valve seat surface 31s, a valve body 32 having a seat surface 32s that seats on the valve seat surface 31s, and a drive unit 33 that drives the valve body 32.

[0028] The orifice 31 is accommodated in the accommodation recess 21. Here, the orifice 31 has a valve seat surface 31s formed on the upper surface thereof, and is accommodated in the accommodation recess 21 so that the valve seat surface 31s faces the upper opening side of the accommodation recess 21.

[0029] As shown in Figure 2, this orifice 31 has an inlet 31i and an outlet 31o formed on the valve seat surface 31s, and a first internal flow path 311 and a second internal flow path 312 connected to the inlet 31i and the outlet 31o.

[0030] When the orifice 31 is accommodated in the accommodation recess 21, the first internal flow path 311 is provided to surround the bottom opening of the accommodation recess 21, and the lower surface of the orifice 31 is provided liquid-tightly on the bottom surface of the accommodation recess 21 via a sealing member such as a metal O-ring (see FIG. 1). In other words, all of the fluid flowing through the upstream flow path R1 flows into the first internal flow path 311 of the orifice 31. Details of the other orifices 31 will be described later.

[0031] The valve element 32 is formed integrally with a diaphragm member 34 that is provided to close the opening of the accommodating recess 21 of the flow path block 2. The side peripheral edge of the diaphragm member 34 is fixed liquid-tightly to the peripheral edge of the upper opening of the accommodating recess 21 via a sealing member such as a metal O-ring.

[0032] As shown in FIG. 2, the central portion of the diaphragm member 34 (i.e., the lower surface of the valve body 32) has a seating surface 32s that moves toward and away from the orifice 31 by the drive unit 33 and seats on or lifts off from the valve seat surface 31s of the orifice 31.

[0033] The drive unit 33 includes a piezo actuator 331 formed by stacking multiple piezo elements that expand and deform when a voltage is applied. The piezo actuator 331 is housed in a casing 332, and an intermediate member 333, such as a sphere, is provided at the tip of the piezo actuator 331. The intermediate member 333 presses against the upper surface of the valve body 32.

[0034] When a predetermined voltage is applied to the piezo actuator 331, the piezo actuator 331 expands, urging the valve element 32 in the valve closing direction, causing the seating surface 32s to approach the valve seat surface 31s by a distance corresponding to the applied voltage, achieving a predetermined opening degree, and reaching a fully closed state when the seating surface 32s comes into contact with the valve seat surface 31s. On the other hand, in the normal state where no voltage is applied to the piezo actuator 331, the valve element 32 is fully opened by the elastic restoring force of the diaphragm member 34.

[0035] The flow rate sensor 4 is, for example, a thermal type, and includes a flow dividing element (fluid resistance) 41 provided in the flow path R, a thin tube 42 that branches from the upstream side of the flow dividing element 41 and joins the downstream side of the flow dividing element 41, two electric heating coils 43 that are wound around the thin tube 42 and to which voltages are applied so that they are kept at constant temperatures, and a flow rate calculation unit 44 that detects the difference in voltage applied to the electric heating coils 43 to calculate the flow rate of the gas flowing through the flow path R. This flow rate sensor 4 is provided in the flow path R on the upstream side or downstream side of the fluid control valve 3.

[0036] The control unit 5 controls the fluid control valve 3 based on the measurement value (measured flow rate) measured by the flow rate sensor 4. The control unit 5 is a computer equipped with a CPU, memory, A / D converter, D / A converter, and various input / output means, and controls the fluid control valve 3 by executing a fluid control program stored in the memory and cooperating with the CPU and peripheral devices.

[0037] The control unit 5 controls the opening degree of the fluid control valve 3 based on a command flow rate input from outside and a measured flow rate measured by the flow sensor 4. Specifically, the control unit 5 controls the opening degree of the fluid control valve 3 so as to reduce the deviation between the command flow rate and the measured flow rate. The control unit 5 of this embodiment performs a PID calculation on the deviation between the command flow rate and the measured flow rate, and outputs a command voltage corresponding to the result to the drive circuit of the drive unit 33. The drive circuit applies a voltage corresponding to the input command voltage to the piezo actuator 331.

[0038] 3 to 6, the orifice 31 of this embodiment is generally disk-shaped, and has a valve seat surface 31s formed on its upper surface and having a circular outer contour, with multiple inlets 31i and multiple outlets 31o that open along a first direction. Note that the first direction is the X direction in FIGS. 3 to 6, a second direction that intersects with the first direction (here, it is perpendicular, but it may be other than perpendicular) is the Y direction, and a direction perpendicular to the X and Y directions is the Z direction.

[0039] The multiple inlets 31i and the multiple outlets 31o have linear, elongated opening shapes extending along the first direction (X direction). Here, the multiple inlets 31i and the multiple outlets 31o are formed along the first direction from one end to the other end of the outer periphery of the valve seat surface 31s. In this embodiment, the opening width (dimension in the second direction (Y direction)) of each inlet 31i in the second direction (Y direction) is constant along the first direction (X direction). Furthermore, the multiple inlets 31i have the same opening width. Similarly, the opening width of each outlet 31o in the second direction (Y direction) is constant along the first direction (X direction). Furthermore, the multiple outlets 31o have the same opening width.

[0040] The multiple inlets 31i and the multiple outlets 31o are arranged alternately in a second direction (Y direction) intersecting the first direction (X direction). The multiple inlets 31i and the multiple outlets 31o are arranged at equal intervals in the second direction (Y direction). In this way, the multiple inlets 31i and the multiple outlets 31o are formed in a striped pattern on the valve seat surface 31s of the orifice 31. Furthermore, linear valve seat surfaces 31s extending along the first direction are formed between the inlets 31i and the outlets 31o adjacent to each other in the second direction (Y direction).

[0041] Specifically, the orifice 31 has a first internal flow path 311 that opens to the valve seat surface 31s and an opposing surface 31t that faces the valve seat surface 31s, and a second internal flow path 312 that opens to the valve seat surface 31s and an outer peripheral surface 31u between the valve seat surface 31s and the opposing surface 31t.

[0042] The first internal flow path 311 is formed to extend in the Z direction, is connected to the plurality of inlets 31i, and has a junction flow path 311a that opens to the opposing surface 31t, and a plurality of branch flow paths 311b that branch off from the junction flow path 311a and open to the valve seat surface 31s. Note that, as shown in FIG. 5, the vertical cross section of the first internal flow path 311 along the YZ plane has a comb-like shape.

[0043] The junction flow path 311a is a flow path into which fluid flows from the upstream flow path R1 that opens at the bottom surface of the accommodating recess 21. The junction flow path 311a is a flow path that has, for example, a circular cross section.

[0044] Each of the branch flow paths 311b is connected to a corresponding one of the inlets 31i, and the fluid from the junction flow path 311a is branched and guided to each of the inlets 31i. The branch flow paths 311b are formed at equal intervals in the second direction, and the cross-sectional shape (cross-sectional shape along the XY plane) of each of the branch flow paths 311b is substantially the same as the opening shape of the inlet 31i with which it is connected.

[0045] The second internal flow passage 312 communicates with the plurality of outlets 31o, and a plurality of second internal flow passages 312 are formed corresponding to the plurality of outlets 31o. Specifically, the second internal flow passage 312 is formed by penetrating the orifice 31 along the first direction (X direction), which is the longitudinal direction of the outlets 31o. That is, the second internal flow passage 312 communicates with the outlets 31o and opens to the outer peripheral surface 31u of the orifice 31 on both longitudinal sides of the outlets 31o. In this embodiment, the second internal flow passage 312 opens to the outer peripheral surface 31u of the orifice 31 at two locations. Note that the shape of the opening of the outer peripheral surface 31u of the second internal flow passage 312 is rectangular, but may be other shapes.

[0046] The second internal flow path 312 is formed along the first direction (X direction) within a side wall portion 313 in the second direction (Y direction) that forms each of the plurality of branch flow paths 311b in the orifice 31 (see FIG. 5 ). That is, the plurality of second internal flow paths 312 and the plurality of branch flow paths 311b are formed alternately in the second direction (Y direction), similar to the plurality of inlets 31i and the plurality of outlets 31o. Here, with regard to the configuration of the side wall portion 313, a recessed groove 313m that opens onto the valve seat surface 31s is formed in the side wall portion 313, and the upper opening of the recessed groove 313m becomes the outlet 31o, and the upper surface of the side wall portion 313 forms part of the valve seat surface 31s.

[0047] With the above orifice structure, the linear, elongated inlet 31i (see FIG. 6(b)) and the linear, elongated outlet 31o (see FIG. 6(c)) are adjacent to each other, and the boundary surface (part of the valve seat surface 31s) between the inlet 31i and the outlet 31o extends linearly (see FIG. 6(a)). This makes it possible to lengthen the boundary surface per unit area of ​​the valve seat surface 31s. Here, by increasing the number of inlets 31i and outlets 31o and reducing the pitch (width) of the inlets 31i and outlets 31o, the number of boundary surfaces can be increased and the width of the boundary surfaces can be reduced. This reduces pressure loss in the orifice 31, allowing a large flow rate of fluid to flow.

[0048] FIG. 7 shows the results of a simulation of the boundary length versus flow rate for orifices 31 with different boundary lengths (present examples (1) to (5)) and an orifice with a conventional configuration (conventional example). Here, the distance (opening) between the valve seat surface 31s and the seating surface 32s is 30 μm. In the figure, "stripe type" indicates this present example, and "existing" indicates the conventional example. The boundary lengths of present examples (2) to (4) are between the boundary length of present example (1) and the boundary length of (5), and gradually increase in the order of (2), (3), and (4). As can be seen from FIG. 7, in this embodiment, the opening widths of the multiple inlets 31i and the multiple outlets 31o are reduced and their numbers are increased, thereby increasing the boundary length, allowing a larger flow rate of fluid to flow.

[0049] In addition, a recess 31N is formed around the entire outer peripheral surface 31u of the orifice 31 (see FIGS. 3 and 5). This recess 31N enlarges the flow path between the orifice 31 and the accommodation recess 21, reducing pressure loss and enabling a large flow rate.

[0050] The orifice 31 may be formed by subjecting a base material to machining such as cutting, or by dividing the base material into a plurality of pieces, processing the divided elements into a predetermined shape by etching or the like, and then joining the processed divided elements.

[0051] Next, a brief description will be given of the flow of fluid in the open state of the fluid control valve 3. When the seating surface 32s is separated from the valve seating surface 31s (open state), the fluid flows from the upstream flow path R1 of the flow path block 2 to the converging flow path 311a of the orifice 31, and then flows from the branch flow paths 311b through the inlets 31i between the valve seating surface 31s and the seating surface 32s. The fluid then flows into the outlets 31o and flows through the second internal flow path 312 between the outer circumferential surface 31u of the orifice 31 and the inner circumferential surface of the installation recess 21. The fluid then flows out of the downstream flow path R2 of the flow path block 2.

[0052] The orifice 31 having the above-described configuration can allow a large flow rate of fluid to flow, but an even larger flow rate of fluid can also be allowed to flow by adjusting the angle at which the orifice 31 is disposed in the installation recess 21 .

[0053] Next, we will explain the arrangement angle of the orifice 31 in the accommodating recess 21. Here, as shown in Fig. 8(a), a state in which the outflow direction of the downstream flow path R2 opening on the inner circumferential surface of the accommodating recess 21 and the longitudinal direction of the outflow port 31o of the orifice 31 (the longitudinal direction of the second internal flow path 312) coincide is defined as 0 degrees, and the angle formed between the outflow direction and the longitudinal direction of the outflow port 31o is defined as an arrangement angle θ.

[0054] 8B shows the change in flow rate according to the arrangement angle θ of the orifice 31. Here, the change in flow rate is shown when the distance (opening) between the valve seat surface 31s and the seating surface 32s is 20 μm and the outer diameter (Φ) of the valve seat surface 31s is 9.9 mm and 15 mm.

[0055] These results show that the flow rate can be increased by setting the arrangement angle θ of the orifice 31 to 15 degrees or more and 75 degrees or less. Furthermore, it can be seen that the flow rate can be further increased by setting the arrangement angle θ of the orifice 31 to 30 degrees or more and 60 degrees or less.

[0056] <Effects of the Present Embodiment> In the fluid control device 100 of the present embodiment configured as described above, the multiple inlets 31 i and the multiple outlets 31 o opening along the first direction are arranged alternately in the second direction intersecting the first direction, so that the boundary surface between the inlets 31 i and the outlets 31 o can be made longer than in a conventional orifice having a concentric groove, thereby reducing pressure loss and allowing a large flow rate of fluid to flow. As a result, the flow rate of the fluid control valve 3 can be increased without increasing the size of the orifice 31 or the piezoelectric actuator 331.

[0057] In addition, multiple second internal flow paths 312 are formed corresponding to each of the multiple outlets 31o, and are shaped along the first direction, i.e., extending in one axial direction, so that the outflow direction of the fluid can be determined and pressure loss can be reduced.

[0058] Furthermore, since the first internal flow path 311 has the merging flow path 311a, it is possible to reduce pressure loss when a large flow rate is flowing.

[0059] Furthermore, since the second internal flow path 312 is formed within the side wall portion 313 that forms each of the multiple branch flow paths 311b, the converging flow path 311a of the first internal flow path 311 is not restricted by the second internal flow path 312, and the flow path volume of the converging flow path 311a can be increased, thereby reducing pressure loss when flowing a large flow rate.

[0060] <Other Embodiments> For example, as shown in FIGS. 9 to 11 , the orifice 31 may have one or more outer internal flow paths 314, one end of which opens to the periphery of the valve seat surface 31 s and the other end of which opens to the outer circumferential surface 31 u or the opposing surface 31 t.

[0061] Specifically, the orifice 31 has a valve seat surface 31s that has a circular outer shape in a plan view, and an annular groove 31M is formed around the valve seat surface 31s on the upper surface where the valve seat surface 31s is formed. One end of the outer internal flow path 314 opens to the bottom surface of the groove 31M.

[0062] The other end of the outer internal flow path 314 opens to the outer peripheral surface 31u of the orifice 31, in this case, to a recess 31N formed in the outer peripheral surface 31u. With this configuration, the fluid flowing into the dead space formed around the valve seat surface 31s can be discharged.

[0063] FIG. 12 shows the results of a simulation of the aperture-flow rate characteristics of the orifice 31 (this embodiment) shown in FIGS. 9 to 11 and an orifice with a conventional configuration (conventional example). Note that "stripe type" in the figure indicates this embodiment, and "existing" indicates the conventional example. As can be seen from FIG. 12, the boundary surface between the inlet and outlet is longer in this embodiment. Furthermore, in this embodiment, the aperture required to control a flow rate of 60 L / min can be reduced by approximately 30% compared to the conventional example. This eliminates the need to enlarge the piezo actuator 331 or the orifice 31 in order to increase the aperture.

[0064] In addition, although the multiple inlets 31i in the above embodiment have the same opening width (dimension in the second direction), they may be different from each other. The opening widths of the multiple outlets 31o may also be different from each other. Furthermore, the opening widths of the inlet 31i and the outlet 31o may be the same or different from each other. The opening width of the inlet 31i or the outlet 31o may vary in the first direction. Furthermore, the multiple inlets 31i or the multiple outlets 31o do not have to be parallel to each other, and the inlet 31i and the outlet 31o do not have to be parallel to each other.

[0065] Furthermore, although the inlet 31i and the outlet 31o in the above embodiment are linear and extend in the first direction, they may be curved or wavy and extend along the first direction.

[0066] In the above embodiment, the plurality of inlets 31i and the plurality of outlets 31o are alternately arranged, but they do not necessarily have to be alternately arranged. For example, various arrangements are possible, such as a configuration in which two inlets 31i and two outlets 31o are alternately arranged, or a configuration in which two outlets 31o are arranged on each side of two inlets 31i.

[0067] Furthermore, in the above embodiment, the inlet 31i is connected to the first internal flow path 311 and the outlet 31o is connected to the second internal flow path 312, but the configuration may be reversed, i.e., the inlet 31i is connected to the second internal flow path 312 and the outlet 31o is connected to the first internal flow path 311.

[0068] In addition, the opening portions of the first internal flow path 311 and the second internal flow path 312 in the above embodiment are not limited to the above embodiment, and the first internal flow path 311 may open to the outer peripheral surface 31u of the orifice 31, and the second internal flow path 312 may open to the opposing surface 31t of the orifice 31.

[0069] Furthermore, although the flow rate sensor 4 in the above embodiment is of a thermal type, it may be of a pressure type.

[0070] 13, the pressure-type flow sensor 4 has a laminar flow element 45 provided in the flow path R, a first pressure sensor 46 that measures the pressure upstream of the laminar flow element 45, a second pressure sensor 47 that measures the pressure downstream of the laminar flow element 45, and a flow rate calculation unit 48 that calculates the flow rate of the fluid flowing through the flow path R based on the first pressure and the second pressure measured by the first pressure sensor 46 and the second pressure sensor 47. This flow rate sensor 4 is provided in the flow path R on the upstream side or downstream side of the fluid control valve 3. Note that instead of the laminar flow element 45, other fluid resistances such as a sonic nozzle may be used.

[0071] In addition, various modifications and combinations of the embodiments may be made as long as they do not go against the spirit of the present invention.

[0072] According to the present invention, it is possible to realize a large flow rate of a fluid control valve without increasing the size of the orifice or actuator.

[0073] 100: Fluid control device 3: Fluid control valve 4: Flow rate sensor 5: Control unit 31: Orifice 31s: Valve seat surface 31t: Opposing surface 31u: Outer peripheral surface 31i: Inlet 31o: Outlet 311: First internal flow path 311a: Merging flow path 311b: Branching flow path 312: Second internal flow path 314: Outer internal flow path 32: Valve body 32s: Seating surface

Claims

1. an orifice having a valve seat surface; a valve body having a seating surface that seats on the valve seat surface, The orifice has a plurality of inlets and a plurality of outlets that open along a first direction in the valve seat surface, A fluid control valve, wherein the plurality of inlets and the plurality of outlets are arranged side by side in a second direction intersecting the first direction.

2. The fluid control valve according to claim 1 , wherein the plurality of inlets and the plurality of outlets are arranged alternately in the second direction.

3. The fluid control valve according to claim 1 , wherein the plurality of inlets and the plurality of outlets are formed along the first direction from one end to the other end of an outer periphery of the valve seat surface.

4. The orifice is a first internal flow passage that opens to the valve seat surface and an opposing surface that faces the valve seat surface; a second internal flow passage that opens to the valve seat surface and an outer circumferential surface between the valve seat surface and the opposing surface; The first internal flow path is in communication with one of the plurality of inlets or the plurality of outlets, The fluid control valve according to claim 1 , wherein the second internal flow passage is in communication with the other of the plurality of inlets or the plurality of outlets.

5. The fluid control valve according to claim 4 , wherein a plurality of the second internal flow passages are formed corresponding to the other of the plurality of inlets or the plurality of outlets, respectively.

6. The fluid control valve according to claim 3 , wherein the second internal flow passage is formed to pass through the orifice along the first direction.

7. The first internal flow path is A junction flow path opening on the opposing surface; a plurality of branch flow paths branching from the joint flow path and opening on the valve seat surface, The fluid control valve according to claim 3 , wherein each of the plurality of branch flow paths is in communication with one of the plurality of inlets or the plurality of outlets.

8. The fluid control valve according to claim 7 , wherein the second internal flow passage is formed within a side wall that defines each of the plurality of branch flow passages.

9. 2. The fluid control valve according to claim 1, wherein the orifice has one or more outer internal passages, one end of which opens to the periphery of the valve seat surface and the other end of which opens to the outer circumferential surface or the opposing surface.

10. A fluid control valve according to any one of claims 1 to 9; a flow sensor for measuring a flow rate of the flow path; a control unit that controls the fluid control valve based on a measurement value of the flow rate sensor.

11. A method for manufacturing an orifice having a valve seat surface on which a valve element of a flow control valve is seated, comprising the steps of: A manufacturing method for an orifice, comprising forming a plurality of inlets and a plurality of outlets that open along a first direction on the valve seat surface of the orifice, and forming the plurality of inlets and the plurality of outlets side by side in a second direction that intersects the first direction.