Fluid controller

Abstract

The purpose of the present invention is to provide a compact fluid controller by disposing a stroke adjustment function component and a valve opening measurement sensor on the same axis.　The present invention comprises: a valve main body 2 in which an inlet passage 21, an outlet passage 22, and a valve chamber 24 that communicates the inlet passage and the outlet passage are formed; a valve body 61 which is provided in the valve chamber, and opens and closes a flow path by abutting and being separated from a valve seat 25 formed in the valve main body; a stem 6 which is provided with the valve body at one end; and an actuator 4 which moves the valve body in the axial direction of the stem. A proximity sensor 8 which measures the position of an end face 63 of the other end of the stem and an adjustment member 7 which adjusts the upper limit movable position of the stem are coaxially provided inside the actuator.

Description

Fluid controller

[0001] This invention relates to a fluid controller.

[0002] The invention shown in Figure 3 is an air-operated valve device described in Patent Document 1, in which a valve body 105a attached to the lower end of a piston 104 is disposed within a valve body 106 in which a passage 107 is formed. When air enters the air chamber 110 in the air operation body 102 and air operation cap 102a from the air intake 109, the piston 104 moves up and down in balance with the internal pressure of the air chamber 110 and the pressing force of the spring 101. As a result, the valve body 105a moves up and down, opening and closing the valve device. The air chamber 110 is airtight with an O-ring 103, and the stroke of the valve body 105a can be adjusted by rotating the operating amount adjustment screw 108.

[0003] The invention described in Patent Document 2, like the invention described in Patent Document 1, has a stroke adjustment function. As shown in Figure 1 of Patent Document 2, the valve 10 includes a regulator 60, which is a rod-shaped member that extends freely through a central opening 54 in the cap 50. The inner end portion 62 of this regulator 60 is screwed onto the piston 42, and the regulator 60 is fixed in its axial movement relative to the piston 42 under the influence of forces applied by a spring 56 and the fluid in the cylinder 40. The stroke can be adjusted by the fixed position of this regulator 60.

[0004] The invention described in Fig. 4 is the valve device 201B described in Patent Document 3, in which a diaphragm retainer 242 presses a diaphragm 241 that comes into contact with and separates from a valve seat of a valve body 202 having a first flow path 221 and a second flow path 222 formed therein. A stem portion 281Bt and a coil spring 245 are disposed inside a bonnet 205, and compressed air CA flowing in from a quick connector 300 at a supply port 264 flows through flow paths 262, 263, 282, etc., and causes an upper piston 281A and a lower piston 281B in an actuator 208 to move up and down. An adjustment member 207 is disposed inside a casing 206, and the upper limit of the stroke is determined when a contact surface 207g on a lower end surface of the adjustment member 207 comes into contact with an upper end surface of the upper piston 281A. The vertical position of the adjustment member 207 is fixed by a lock screw 275 using a tool inserted through an access hole 261. The position of the upper surface of the upper piston 281A can be measured by a position sensor 400. The adjustment of the adjustment member 207 is performed while monitoring the detection value of the position sensor 400. When the vertical position of the upper piston 281A reaches a target position, that is, a position corresponding to a target lift amount, the adjustment of the adjustment member 207 is completed, and the adjustment member 207 is locked by the lock screw 275. According to this method, there is no need to flow an actual gas, so the adjustment operation can be performed more easily.

[0005] The invention described in Patent Document 4 has a stroke adjustment function and a function of monitoring the opening degree of a valve, similar to the invention described in Patent Document 3. In Fig. 8 of Patent Document 4, a valve opening / closing detection sensor 91 for monitoring the opening degree is attached. For stroke adjustment, the valve opening / closing detection sensor 91 is removed, and a stroke adjustment knob 92 shown in Fig. 10 is attached. After the stroke is adjusted with the stroke adjustment knob 92, the valve opening / closing detection sensor 91 is reattached to enable monitoring of the opening degree.

[0006] Jitsukaihei 01-085585, JP 2006-519971, JP 2020-020371, JP 2008-002511

[0007] The inventions described in Patent Documents 1 and 2 have a stroke adjustment function, but lack a valve opening degree monitoring function. The invention described in Patent Document 3 has two functions: a stroke adjustment function and a lift amount monitoring function, but the adjustment member is on the extension of the stem axis, and the position sensor has to be placed at a position away from the stem axis, resulting in a complex structure and making it difficult to realize a compact fluid controller. In the invention described in Patent Document 4, the stroke adjustment function component and the position sensor are placed in the same location, but they cannot be used simultaneously, which is inconvenient.

[0008] The present invention has been made in view of the above, and its purpose is to provide a compact fluid controller by arranging the stroke adjustment function component and the valve opening measurement sensor on the same axis to simplify the mechanism.

[0009] (1) The present invention relates to a fluid controller comprising: a valve body having an inlet passage, an outlet passage, and a valve chamber connecting the inlet passage and the outlet passage; a valve element disposed in the valve chamber that opens and closes a flow path by contacting and separating from a valve seat formed in the valve body; a stem having the valve element at one end; and an actuator that moves the valve element in the axial direction of the stem, wherein a proximity sensor for measuring the position of the end face of the other end of the stem and an adjustment member for adjusting the movable upper limit position of the stem are coaxially disposed inside the actuator.

[0010] In the fluid controller of the present invention (1), a proximity sensor for measuring the position of the end face of the other end of the stem and an adjustment member for adjusting the movable upper limit position of the stem are arranged coaxially inside the actuator. Therefore, the stroke adjustment function component and the valve opening measurement sensor can be arranged coaxially, simplifying the mechanism and thus providing a compact fluid controller.

[0011] The present invention (2) is a fluid controller according to the present invention (1), wherein the upper casing of the actuator has an internal thread cut into it in the axial direction of the stem, the adjustment member has a cylindrical portion having an internal thread that screws into the internal thread, and the proximity sensor facing the end face of the other end is disposed inside the cylindrical portion.

[0012] In the present invention (2), the upper casing of the actuator has an internal thread in the axial direction of the stem, and the adjustment member has a cylindrical portion having an internal thread that screws into the internal thread, and the proximity sensor facing the end face of the other end is disposed inside the cylindrical portion, so that the arrangement of the stroke adjustment function component and the valve opening measurement sensor is simpler and the fluid controller becomes more compact.

[0013] The present invention (3) is a fluid controller according to the present invention (2), wherein a stopper portion is formed on the stem near the other end, facing the lower end surface of the cylindrical portion, and the upper limit of the movable position of the stem is set by the lower end surface of the cylindrical portion and the end surface of the stopper portion coming into contact with each other.

[0014] In the present invention (3), a stopper portion is formed on the stem near the other end, facing the lower end surface of the cylindrical portion. The lower end surface of the cylindrical portion and the end surface of the stopper portion come into contact, thereby setting the upper limit of the stem's movable position, resulting in a structurally simple fluid controller.

[0015] The present invention (4) is a fluid controller according to the present invention (3), wherein the stem has an extended portion that extends from the stopper portion into the interior of the cylindrical portion, and the position of the end face of the extended portion is measured by the proximity sensor.

[0016] In the present invention (4), the stem has an extended portion that extends from the stopper portion into the interior of the cylindrical portion, and the proximity sensor measures the position of the end face of the extended portion. Therefore, the distance between the proximity sensor and the end face can be adjusted according to the characteristics of the proximity sensor, and the position of the proximity sensor does not need to be changed.

[0017] The present invention (5) is a fluid controller according to the present invention (3), wherein the proximity sensor measures the position of the end face of the stopper portion.

[0018] In the present invention (5), the position of the stopper portion can be monitored because the proximity sensor measures the position of the end face of the stopper portion.

[0019] According to the present invention, the stroke adjustment function component and the valve opening measurement sensor can be arranged on the same axis, simplifying the mechanism and providing a compact fluid controller.

[0020] This is a partial cross-sectional view of the fluid controller in the closed state according to the present invention. This is a partial cross-sectional view of the fluid controller in the open state according to the present invention. This is a partial cross-sectional view of the fluid control device described in Patent Document 1. This is a partial cross-sectional view of the fluid control device described in Patent Document 3.

[0021] Embodiments of the present invention will be described in detail below with reference to the drawings. The following embodiments are essentially preferred examples and are not intended to limit the scope of the present invention, its applications, or its uses.

[0022] Figure 1 is a partial cross-sectional view of the entire closed-state fluid controller 1 of the present invention. The fluid controller 1 comprises a valve body 2 having an inlet passage 21, an outlet passage 22, a valve chamber 24, and a valve seat 25, and a bonnet and actuator above the valve body. Inside the valve chamber 24 is a stem 6 with a valve element 61 at its lower end that contacts and separates from the valve seat 25, which passes through an annular flange 34, a bonnet 3, and a piston 45, and is fitted into an adjustment member 7. The area around the stem 6 is airtight with a bellows 64, and the space between the annular flange 34 and the valve body 2 is sealed with an O-ring 33. The female thread 32 of the bonnet nut 31 is screwed into the male thread 23 on the upper part of the valve body 2.

[0023] The actuator 4 comprises a cylinder head (upper casing) 5 and a cylinder 40, with a piston 45 located inside the cylinder 40. The cylinder 40 is positioned above the bonnet 3, and fluid flowing in through a working fluid introduction passage 41 formed in the cylinder 40 enters the working fluid introduction chamber 42, pushing up the piston 45. As the piston 45 moves, it pushes up the stem 6, which is fixed to the piston 45 by a split ring 65, thereby pushing the valve body 61 upward. The space between the cylinder 40 and the bonnet 3 is sealed by an O-ring 35. The space between the stem 6 and the bonnet 3 is sealed by an O-ring 36. The space between the piston 45 and the cylinder 40 is sealed by an O-ring 43. The male thread 46 of the cylinder 40 is screwed into the female thread 51 of the cylinder head (upper casing) 5. A compression coil spring 44 is positioned between the ceiling wall of the cylinder head (upper casing) 5 of the actuator 4 and the piston 45, constantly biasing the piston 45 downward.

[0024] A stopper portion 66 is provided at the top of the stem 6. When the end face 67 of the stopper portion 66 comes into contact with the lower end face 73 of the adjustment member 7, the stem 6 cannot move any further upward, and the valve is fully open when contact is made. The stem 6 has an extension portion 68 further above the stopper portion 66, which becomes the upper end of the stem 6 and extends into the interior of the cylindrical portion 72 of the adjustment member 7. The proximity sensor 8, which is disposed inside the adjustment member 7, faces the end face 63 of the extension portion 68, which is the upper end face of the stem 6. The female thread 53 of the upper casing 5 and the male thread 71 of the adjustment member 7 are screwed together, and the female thread 54 of the nut 52 and the male thread 71 of the adjustment member 7 are screwed together. The vertical position of the adjustment member 7 is determined by these screw connections, and the adjustment member 7 is fixed by the nut 52. If the stem 6 does not have an extension portion 68, the end face 67 of the stopper portion 66 may face the proximity sensor 8. In this case, the position of the end face 67 can be measured by the proximity sensor 8 to adjust the vertical position of the adjustment member 7.

[0025] A signal cable 82 is attached to the upper end of the adjustment member 7 with a lock nut 81. When the proximity sensor 8 detects the vertical position of the upper end surface of the stem 6 and extracts a signal from the signal cable 82, the positional relationship between the valve body 61 and the valve seat 25 can be determined from the position of the upper end surface of the stem 6, thus simplifying the overall mechanism of the fluid controller and enabling the inclusion of a valve opening / closing detection mechanism. Stroke adjustment also becomes easier.

[0026] The proximity sensor 8 can utilize sensors such as inductive proximity sensors, capacitive proximity sensors, and laser proximity sensors. An inductive proximity sensor detects magnetic loss due to eddy currents generated on the surface of a conductor due to the influence of an external magnetic field, generates an alternating magnetic field in a detection coil, and detects the change in impedance due to eddy currents generated in the metal body that is the detection object. A capacitive proximity sensor detects the change in capacitance that occurs between the detection object and the sensor, and is a sensor that detects the capacitance of two parallel plates arranged in parallel, like a capacitor. A laser proximity sensor detects the position information of an object by emitting a "laser" from a light-emitting unit and detecting the time it takes for the laser light to return.

[0027] Figure 2 shows the fully open state where the working fluid enters the working fluid introduction chamber 42 from the working fluid introduction passage 41, the piston 45 is pushed upward, and the end face 67 of the stopper portion 66 contacts the lower end face 73 of the adjustment member 7. By loosening the nut 52 and moving the adjustment member 7 up and down, and then fixing the adjustment member 7 with the nut 52 again, the stroke can be adjusted, and the adjustment becomes easier if signal information from the signal cable 82 is used at that time.

[0028] As described above, the present invention simplifies the mechanism by arranging the stroke adjustment function component and the valve opening measurement sensor on the same axis, and can provide a compact fluid controller.

[0029] 1; Fluid controller 2; Valve body 3; Bonnet 4; Actuator 5; Cylinder head (upper casing) 6; Stem 7; Adjustment member 8; Proximity sensor 21; Inlet passage 22; Outlet passage 23; Male thread 24; Valve chamber 25; Valve seat 31; Bonnet nut 32; Female thread 33; O-ring 34; Annular flange 35; O-ring 36; O-ring 40; Cylinder 41; Working fluid introduction passage 42; Working fluid introduction chamber 43; O-ring 44; Compression coil spring 45; Piston 46; Male thread 51; Female thread 52; Nut 53; Female thread 54; Female thread 61; Valve body 63; End face 64; Bellows 65; Split ring 66; Stopper part 67; End face 68; Extension part 71; Male thread 72; Cylindrical part 73; Lower end face 81; Lock nut 82; Signal cable

Claims

1. A fluid controller comprising: a valve body having an inlet passage, an outlet passage, and a valve chamber connecting the inlet passage and the outlet passage; a valve element disposed in the valve chamber that opens and closes a flow path by contacting and separating from a valve seat formed in the valve body; a stem having the valve element at one end; and an actuator that moves the valve element in the axial direction of the stem, wherein a proximity sensor for measuring the position of the end face of the other end of the stem and an adjustment member for adjusting the movable upper limit position of the stem are disposed coaxially inside the actuator.

2. The fluid controller according to claim 1, wherein the upper casing of the actuator has an internal thread in the axial direction of the stem, the adjustment member has a cylindrical portion having an internal thread that screws into the internal thread, and the proximity sensor facing the end face of the other end is disposed inside the cylindrical portion.

3. The fluid controller according to claim 2, wherein a stopper portion is formed on the stem near the other end, facing the lower end surface of the cylindrical portion, and the upper limit of the movable position of the stem is set by the lower end surface of the cylindrical portion and the end surface of the stopper portion coming into contact with each other.

4. The fluid controller according to claim 3, wherein the stem has an extended portion that extends from the stopper portion into the interior of the cylindrical portion, and the position of the end face of the extended portion is measured by the proximity sensor.

5. The fluid controller according to claim 3, wherein the proximity sensor measures the position of the end face of the stopper portion.

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