Static eliminator for charged fluid

Abstract

To provide a technology capable of removing static electricity from the entire fluid while keeping pressure loss of fluid in a pipe low.SOLUTION: A static eliminator is an instrument used to remove static electricity from fluid in a pipe, and comprises a static elimination rod. The static elimination rod is made of conductive resin, is a member that does not allow fluid to pass through, is grounded, and is arranged in a flow path in the pipe so as to intersect with a center part of the flow path. The static elimination rod includes a cavity at a position where it intersects with the center part of the flow path. The cavity passes through the static elimination rod parallel to a direction of the flow path.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to plumbing equipment, and more particularly to a technique for removing static electricity from fluid in a pipe. [Background technology]

[0002] In semiconductor processes, various chemicals and ultrapure water are used for coating wafers with resist, cleaning wafers, and other processes. Semiconductor manufacturing equipment includes piping equipment, such as tubes, fittings, valves, and pumps, that handle these chemicals. This piping equipment is characterized by the fact that the wetted parts are made of non-metallic materials such as resin. This is because it is necessary to prevent metallic contamination from chemicals, which can cause crystal defects and degradation of the electrical characteristics of semiconductors. Another characteristic of this piping equipment is that it requires relatively frequent maintenance, such as cleaning. This is because it is necessary to prevent the accumulation of fine particles, which can cause wiring processing defects, and organic matter, which can cause film formation abnormalities, in various parts of the piping equipment. Given these characteristics, the piping equipment for semiconductor manufacturing equipment is required to have high sealing properties as well as be easy to assemble and disassemble.

[0003] Because the wetted parts of piping are nonmetallic, flow electrification is likely to occur with low-conductivity fluids, such as organic solvents and ultrapure water. Excessive fluid electrification can easily induce seal damage due to insulation breakdown in valves, potentially resulting in leaks. Furthermore, if the charge carried by the charged fluid accumulates on wafers, it could lead to the destruction of semiconductor devices. Furthermore, if flammable organic solvents are electrified and cause spark discharge, there is even a risk of fire. Therefore, various techniques have been proposed to remove static electricity from fluids in piping. For example, Patent Documents 1 and 2 disclose techniques that make part of the inner wall of the flow path conductive by incorporating carbon fiber into the gasket or sealing material, and then ground that part. Patent Documents 3 and 4 disclose techniques that pass the fluid through a grounded metal mesh or filter. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 04-129993 [Patent Document 2] Japanese Patent Publication No. 2022-114505 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-305095 [Patent Document 4] Japanese Patent Application Laid-Open No. 2003-202098 Summary of the Invention [Problem to be solved by the invention]

[0005] In the technology disclosed in Patent Documents 1 and 2, in which a grounded, highly conductive section (hereinafter referred to as "static removal section") is provided on the inner wall of the flow path, static electricity can be removed from the fluid passing near the inner wall of the flow path, but it is difficult to remove static electricity from the fluid passing through the center in the radial direction of the flow path (hereinafter simply referred to as "center"). Fluids in which the amount of charge can become large enough to become a problem have a fairly low conductivity (typically, 10 -8 This is because, since the electric field strength is less than 1000 s / m, it is difficult to move the charge from the center of the flow path to the inner wall while the fluid is passing through the static elimination section. Extending the static elimination section to allow for this movement in time, or applying a magnetic or electric field to the fluid in the static elimination section to promote the movement of the charge, would make the static elimination structure large-scale or complex, and therefore neither is practical.

[0006] For the sole purpose of sufficiently neutralizing the fluid not only near the inner wall of the flow path but also in the center of the flow path, the use of meshes or filters as disclosed in Patent Documents 3 and 4 is desirable. This is because meshes, etc., come into contact with the fluid not only near the inner wall of the flow path but also in the center of the flow path. However, because meshes, etc., are made of metal, their use in semiconductor processes poses a high risk of contaminating the fluid with metal. It is also difficult to change the material of meshes, etc., from metal to conductive resin. Because meshes, etc., are thin in the direction of flow, conductive resins have high electrical resistance and are unable to extract a sufficient amount of charge from the fluid. Increasing the thickness of meshes, etc., in order to reduce electrical resistance, tends to result in excessive fluid pressure loss due to the mesh, etc.

[0007] An object of the present invention is to solve the above problems, and in particular to provide a technique that can remove static electricity from the entire fluid while keeping the pressure loss of the fluid in the piping low. [Means for solving the problem]

[0008] A static eliminator according to one aspect of the present invention is a device for removing static electricity from a fluid in a pipe, and includes a static eliminator rod. The static eliminator rod is a member made of conductive resin that is impermeable to the fluid, is grounded, and is disposed within a flow path in the pipe so as to intersect with the center of the flow path. The static eliminator rod includes a cavity at the position where it intersects with the center of the flow path. The cavity penetrates the static eliminator rod parallel to the direction of the flow path.

[0009] When the piping is a manifold, the static eliminator may further include a fixed part. The fixed part is in the form of a stopcock (a stopper that blocks an unnecessary open end of a manifold; also called a plug or cap) and removably blocks one branch of the manifold. A static eliminator rod may extend from the fixed part through the branch to beyond the center of the flow path in the manifold. The static eliminator rod may include multiple fins. Each fin extends from within the branch path blocked by the fixed part to beyond the center of the flow path and is parallel to the direction of the flow path. In this case, the cavity of the static eliminator rod is a slit formed by the fins. [Effects of the Invention]

[0010] The static eliminator according to the present invention uses a static eliminator rod to guide a fluid passing through the center of a flow path in a pipe into the cavity of the static eliminator rod. Because the static eliminator rod is disposed within the flow path, the cavity of the static eliminator rod is narrower than the flow path. Therefore, even if the fluid has low conductivity, static electricity can be sufficiently removed from the fluid passing through the cavity. In particular, the surface area of ​​the inner wall of the cavity adjusts the electrical resistance of the static eliminator rod, and the cross-sectional area of ​​the cavity adjusts the pressure loss of the fluid. When the static eliminator rod includes fins, the surface area of ​​the inner wall of the cavity can be easily designed by the surface area of ​​the fins, and the cross-sectional area of ​​the cavity can be easily designed by the spacing between the fins. Therefore, by optimizing the surface area and cross-sectional area of ​​the inner wall of the cavity, static electricity can be removed from the entire fluid while keeping the pressure loss of the fluid low.

[0011] When the static eliminator is equipped with the above-described fixing portion, the structure of the existing manifold can be used as is for fixing the static eliminator rod and for sealing. This simplifies both installation and removal of the static eliminator, while ensuring high stability of the static eliminator rod and high reliability of the seal. Furthermore, the cavity that penetrates the static eliminator rod may also be provided in the branch passage of the manifold, or may extend into the branch passage. This increases the surface area of ​​the inner wall of the cavity, further reducing the electrical resistance of the static eliminator rod. Furthermore, the cross-sectional area of ​​the cavity is also increased, further reducing pressure loss of the fluid. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view of a static eliminator according to a first embodiment of the present invention. [Figure 2] 2 is a longitudinal sectional view of the static eliminator taken along a plane including the line II-II shown in FIG. 1. FIG. [Figure 3] 3 is a cross-sectional view of the static eliminator taken along a plane including the line III-III shown in FIG. 1. FIG. [Figure 4] FIG. 10 is a vertical cross-sectional view of a static eliminator according to a second embodiment of the present invention. [Figure 5]FIG. 5 is a cross-sectional view of the static eliminator shown in FIG. [Figure 6] FIG. 10 is a vertical cross-sectional view of a modified example of the static eliminator according to the second embodiment of the present invention. [Figure 7] FIG. 7 is a cross-sectional view of the static eliminator shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First Embodiment [Structure of static eliminator]

[0014] FIG. 1 is a perspective view of a static eliminator 100 according to a first embodiment of the present invention. The static eliminator 100 closes, for example, the branch pipe section 210 of a tee pipe 200. The tee pipe 200 (also called a T-shaped pipe) is a three-pronged pipe joint, with the branch pipe section 210 protruding vertically (upward in FIG. 1) from a straight main pipe section 220. The main pipe section 220 connects a tube 510 to another tube 520. The tee pipe 200 is preferably made of a fluororesin such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), or perfluoroalkoxyalkane (PFA). The tubes 510 and 520 are preferably made of a fluororesin such as PTFE or PFA.

[0015] FIG. 2 is a longitudinal cross-sectional view of the static eliminator 100 taken along a plane including line II-II in FIG. 1 (i.e., a cross-sectional view parallel to the longitudinal direction of the main pipe portion 220 of the tee 200). FIG. 3 is a transverse cross-sectional view of the static eliminator 100 taken along a plane including line III-III in FIG. 1 (i.e., a cross-sectional view perpendicular to the longitudinal direction of the main pipe portion 220). As shown in FIG. 2, the main pipe portion 220 contains a flow path 221 connecting the two tubes 510 and 520. The branch pipe portion 210 of the tee 200 contains a branch path 211 that protrudes from the middle of the flow path 221 perpendicularly (upward in FIG. 2) to the direction of the flow path 221 (the left-right direction in FIG. 2). The tip end (the upper end in FIGS. 2 and 3) of the branch pipe portion 210 has a double structure consisting of an outer tube 213 and an inner tube 214. The outer tube 213 includes a male thread 215 on its outer circumferential surface. The inner cylinder 214 has a tip (upper end in FIGS. 2 and 3) that includes an inversely tapered truncated cone surface 216. The portion where the inner peripheral surface of the outer cylinder 213 and the outer peripheral surface of the inner cylinder 214 face each other forms an annular groove 217.

[0016] The static eliminator 100 is removably fitted into the outer tube 213 of the branch pipe section 210, and closes the branch pipe 211. As shown in FIGS. 2 and 3, the static eliminator 100 includes a static eliminator rod 110, a fixing section 120, and a union nut .

[0017] The static eliminator 110 is a square rod-shaped member, and its cross section perpendicular to the longitudinal direction, i.e., its transverse cross section, is smaller than that of the branch path 211 of the tee 200. The static eliminator 110 is arranged coaxially within the branch path 211, and extends from within the branch path 211 to beyond the center of the flow path 221. The static eliminator 110 is made of a resin that is more conductive than fluororesin, preferably a fluororesin such as PFA in which a conductive material such as carbon fiber is dispersed, and has a higher conductivity than the tee 200.

[0018] The tip end (lower end in FIGS. 2 and 3 ) 111 of the static eliminator 110 is disposed in the flow path 221 of the tee 200 so as to intersect with the center of the flow path 221, and as shown in FIG. 3 , includes four fins 112. The fins 112 are parallel to the direction of the flow path 221 (the left-right direction in FIG. 2 ). The fins 112 are arranged at equal intervals in a direction perpendicular to the direction of the flow path 221 (the left-right direction in FIG. 3 ), forming three slits 113. The slits 113 are hollows that penetrate the static eliminator 110 parallel to the direction of the flow path 221 and extend from the tip end (lower end in FIGS. 2 and 3 ) of the static eliminator 110 to the inside of the branch path 211. The depth THC of the slit 113, i.e., the width of the fins 112 (the size in the direction of the flow path 221) is narrower than the inner diameter of the branch path 211. The width WDT of the slits 113, i.e., the spacing between the fins 112, is about 10% of the inner diameter of the flow path 221. The height HGT of the slits 113, i.e., the length of the fins 112 (the size in the direction perpendicular to the direction of the flow path 221 (the up-and-down direction in FIGS. 2 and 3)) is about 1.5 times the inner diameter of the flow path 221. The static elimination rod 110 does not allow the fluid flowing from the tubes 510 and 520 into the flow path 221 to pass through, so the fluid not only detours around the static elimination rod 110 but also passes through each slit 113. In particular, the fluid that has passed through the center of the flow path 221 flows into the central slit 113.

[0019] The fixed part 120 is a cylindrical member, and its tip (lower end in FIGS. 2 and 3) is coaxially connected to the base end (upper end in FIGS. 2 and 3) of the static elimination rod 110. The fixed part 120 has an outer diameter substantially equal to the inner diameter of the outer tube 213 of the tee 200 (i.e., the difference between the outer diameter of the fixed part 120 and the inner diameter of the outer tube 213 is within the dimensional tolerance), and removably closes the outer tube 213. In other words, the fixed part 120 has the shape of a stopper. Like the static elimination rod 110, the fixed part 120 is formed from a highly conductive resin and has a higher conductivity than the tee 200. The base end (upper end in FIGS. 2 and 3) of the fixed part 120 is connected to a ground electrode (not shown) via a conductor or the like (not shown). Preferably, the fixed part 120 is molded integrally with the static elimination rod 110. Therefore, the entire static elimination rod 110 and the fixed part 120 are maintained at ground potential.

[0020] The tip end (lower end in FIGS. 2 and 3) of the fixed part 120 includes an annular protrusion 121 and a tapered truncated conical surface 122. The annular protrusion 121 protrudes axially (downward in FIGS. 2 and 3) from the entire circumference of the fixed part 120 and is press-fit into an annular groove 217 of the tee 200. In particular, the inner diameter of the annular protrusion 121 is slightly narrower than the outer diameter of the inner tube 214 of the tee 200. Therefore, the inner circumferential surface of the annular protrusion 121 and the outer circumferential surface of the inner tube 214 closely contact each other, forming a seal. The truncated conical surface 122 of the fixed part 120 is coaxially disposed inside the base end (upper end in FIGS. 2 and 3) of the annular protrusion 121 and closely contacts the truncated conical surface 216 of the inner tube 214.

[0021] The base end of the fixed part 120 (the upper end in Figures 2 and 3) includes a flange 123 and a handle hole 124. The flange 123 projects outward from the outer peripheral surface of the fixed part 120, close to the outer peripheral surface of the outer cylinder 213 of the tee 200. The handle hole 124 is a through-hole that extends straight in a direction perpendicular to the central axis 125 of the fixed part 120. When the fixed part 120 is removed from the branch pipe part 210 of the tee 200, a rod-shaped handle (not shown) is inserted into the handle hole 124 and used to pull the fixed part 120 out of the branch pipe part 210. Preferably, the longitudinal direction of the handle hole 124 is the same as the direction of the fins 112 of the static elimination rod 110, i.e., the direction of the flow path 221 of the tee 200. When the fixing part 120 is attached to the branch pipe part 210 , the direction of the handle hole 124 is aligned with the direction of the flow path 221 , so that the fins 112 can be aligned parallel to the direction of the flow path 221 .

[0022] The union nut 130 is a cylindrical member preferably made of a fluororesin such as PVDF, PTFE, or PFA, and coaxially surrounds the fixed part 120 and the outer cylinder 213 of the tee 200. A female thread 134 is formed on the inner circumferential surface of a tip end (lower end in FIGS. 2 and 3) 131 of the union nut 130, and a step 135 is formed on the inner circumferential surface of a base end (upper end in FIGS. 2 and 3). The female thread 134 meshes with the male thread 215 of the outer cylinder 213. The step 135 has an inner diameter narrower than the female thread 134, and contacts the flange 123 of the fixed part 120 from the side opposite the static elimination rod 110 (the upper side in FIGS. 2 and 3). As a result, when the female threads 134 of the union nut 130 are screwed onto the male threads 215 of the outer tube 213, the axial force from the union nut 130 is applied to the flange 123 via the step portion 135 and transmitted to the annular protrusion 121 and the annular surface 122 of the fixing part 120. As a result, the inner peripheral surface of the annular protrusion 121 further increases the sealing pressure against the outer peripheral surface of the inner tube 214 of the tee 200, and the truncated cone surface 122 forms a seal with the truncated cone surface 216 of the inner tube 214. In this way, the branch passage 211 of the tee 200 is doubly sealed. [Static elimination effect]

[0023] The static eliminator 100 uses a static eliminator rod 110 to guide a fluid passing through the center of a flow path 221 in a Tee 200 into the slit 113 of the static eliminator rod 110. The gap between each slit 113 and the inner wall of the flow path 221 is narrower than the flow path 221. Therefore, even if the fluid has low conductivity, such as ultrapure water, the charge stored in the fluid can be released to the static eliminator rod 110 as the fluid passes through the static eliminator rod 110. Therefore, static electricity can be sufficiently removed from both the fluid passing through the slit 113 and the fluid bypassing the static eliminator rod 110. In particular, the surface area THC×HGT of the inner wall of the slit 113 (see FIG. 2) adjusts the electrical resistance of the static eliminator rod 110, and the cross-sectional area WDT×HGT of the slit 113 adjusts the pressure loss of the fluid caused by the static eliminator rod 110. The surface area of ​​the inner wall of slit 113 can be easily designed by the width THC and height HGT of fin 112, and the cross-sectional area of ​​slit 113 can be easily designed by the spacing WDT and height HGT of fin 112. Therefore, by optimizing the surface area and cross-sectional area of ​​the inner wall of slit 113, static electricity can be removed from the entire fluid while keeping the pressure loss of the fluid low.

[0024] Because the fixing portion 120 is in the shape of a stop plug, the structure of the existing tee 200, particularly the double seal structure formed by the outer tube 213 and inner tube 214, can be used as is to fix the static eliminator 110 and seal the branch passage 211. This makes it easy to attach and detach the static eliminator 100, while ensuring high stability of the static eliminator 110 and high sealing reliability. Furthermore, because the slit 113 extends into the branch passage 211 of the tee 200, the surface area of ​​the inner wall of the slit 113 is sufficiently large, making it easy to reduce the electrical resistance of the static eliminator 110, and the cross-sectional area of ​​the slit 113 is also sufficiently large, making it easy to suppress pressure loss of the fluid. [Variations]

[0025] (1) Although the static eliminator 100 closes the branch pipe 210 of the tee 200, the invention is not limited to this. For example, the static eliminator 100 may close one open end of the main pipe 220. In this case, the space extending from the other open end of the main pipe 220 to the branch pipe 211 may be used as a flow path. Also, instead of the tee 200, the pipe joint may be a Y-shaped pipe, a cross, or a manifold with four or more open ends.

[0026] (2) The shapes and sizes of each part of the static eliminator 100 are merely examples. For example, the static eliminator rod 110 may be a round rod or a flat plate instead of a square rod. The number of fins 113 is not limited to four, but may be three or less, or five or more. The surfaces of the fins 113 may be curved instead of flat. Furthermore, instead of the fins 113, an array of multiple rod-shaped members may be provided at the tip 111 of the static eliminator rod 110.

[0027] (3) In the static eliminator 100, the static eliminator 110 and the fixed part 120 are integrally molded from the same conductive resin. This makes the entire static eliminator 110 conductive. Alternatively, only the static eliminator rod 110 may be made of conductive resin. In this case, a conductive part such as a conductor is embedded in the fixed part 120, and the static eliminator rod 110 is electrically connected to an external ground electrode. Second Embodiment

[0028] Fig. 4 is a longitudinal sectional view of a static eliminator 150 according to a second embodiment of the present invention, and Fig. 5 is a transverse sectional view of the static eliminator 150 shown in Fig. 4. Compared to the static eliminator 100 according to the first embodiment, the static eliminator 150 according to the second embodiment differs only in the structure of the tip 151 of the static eliminator rod 110. Since the other structures are the same, only the different structures will be described below, and the above description of the first embodiment will be used for the common structures.

[0029] The static eliminator 110 is rod-shaped, and its tip (the lower end in FIGS. 4 and 5) 151 is disposed in the flow path 221 of the tee 200 so as to intersect with the center of the flow path 221. As shown in FIG. 5, the tip 151 includes a cylindrical cavity 152. The cavity 152 penetrates the static eliminator 110 parallel to the direction of the flow path 221 (the left-right direction in FIG. 4). The depth THC of the cavity 152 is narrower than the inner diameter of the branch path 211. The inner diameter DMT of the cavity 152 is, for example, approximately 25% of the inner diameter of the flow path 221. In the radial direction of the flow path 221, the cavity 152 is located in the center of the flow path 221. The static eliminator 110 does not allow fluid flowing from the tubes 510 and 520 into the flow path 221 to pass through, so the fluid not only bypasses the static eliminator 110 but also passes through the cavity 152. In particular, the fluid that has passed through the center of the flow path 221 flows into the cavity 152 .

[0030] The static eliminator 100 uses the static eliminator rod 110 to guide a fluid passing through the center of a flow path 221 in a tee 200 into a cavity 152 in the static eliminator rod 110. Both the cavity 152 and the gap between the static eliminator rod 110 and the inner wall of the flow path 221 are narrower than the flow path 221. Therefore, even if the fluid has low conductivity, such as ultrapure water, the charge stored in the fluid can be released to the static eliminator rod 110 while the fluid passes through the static eliminator rod 110. Therefore, static electricity can be sufficiently removed from both the fluid passing through the cavity 152 and the fluid bypassing the static eliminator rod 110. In particular, the electrical resistance of the static eliminator rod 110 is adjusted by the surface area of ​​the tip 151 of the static eliminator rod 110 and the surface area of ​​the inner wall of the cavity 152, 2π×DMT×THC (see FIG. 4), and the cross-sectional area of ​​the cavity 152, π×DMT 2 (See FIG. 5) adjusts the pressure loss of the fluid caused by the static elimination rod 110. Therefore, by optimizing the surface area and cross-sectional area of ​​the inner wall of the cavity 152, static electricity can be removed from the entire fluid while keeping the pressure loss of the fluid low. [Variations]

[0031] The shape and size of cavity 152 are merely examples. For example, the cross-sectional shape of cavity 152 may be an ellipse or a polygon instead of a circle. The number of cavities 152 is not limited to one, and may be two or more.

[0032] Fig. 6 is a longitudinal sectional view of a modified static eliminator 170 according to embodiment 2 of the present invention, and Fig. 7 is a transverse sectional view of the static eliminator 170 shown in Fig. 6. Compared to the static eliminator 110 according to embodiment 1, the static eliminator 170 according to the modified embodiment of embodiment 2 differs only in the structure of the tip 171 of the static eliminator rod 110. Since the other structures are the same, only the different structures will be described below, and the above description of embodiment 1 will be used for the common structures.

[0033] The static eliminator 110 is round and has a tip (lower end in FIGS. 6 and 7) 171 disposed in the flow path 221 of the tee 200 so as to intersect with the center of the flow path 221. As shown in FIG. 6, the tip 171 includes multiple cavities 172 (five in FIGS. 6 and 7). Each cavity 172 penetrates the static eliminator 110 parallel to the direction of the flow path 221 (the left-right direction in FIG. 6). The depth THC of each cavity 172 is narrower than the inner diameter of the branch path 211. The inner diameter DMT of each cavity 172 is uniform, for example, to about 25% of the inner diameter of the flow path 221. In the direction perpendicular to the direction of the flow path 221 (the up-down direction in FIGS. 6 and 7), the cavities 172 are aligned in a row at equal intervals along the central axis 125 of the static eliminator 110, from the inside of the branch path 211 to beyond the center of the flow path 221. The cavities 172 may be in two or more rows, and the inner diameter, shape, or spacing may not be uniform. The static elimination rod 110 does not allow the fluid flowing from the tubes 510 and 520 into the flow path 221 to pass through, so the fluid not only detours around the static elimination rod 110 but also passes through all of the cavities 172. In particular, the fluid that has passed through the center of the flow path 221 flows into the cavity 172 closest to the tip of the static elimination rod 110.

[0034] The static eliminator 100 uses the static eliminator rod 110 to guide the fluid passing through the center of the flow path 221 in the Tee 200 into the cavity 172 of the static eliminator rod 110. Since each cavity 172 and the gap between the static eliminator rod 110 and the inner wall of the flow path 221 are narrower than the flow path 221, even if the fluid has low conductivity such as ultrapure water, the charge stored in the fluid can be released to the static eliminator rod 110 while the fluid passes through the static eliminator rod 110. Therefore, static electricity can be sufficiently removed from both the fluid passing through the cavities 172 and the fluid bypassing the static eliminator rod 110. In particular, the electrical resistance of the static eliminator rod 110 is adjusted by the surface area of ​​the static eliminator rod 110 and the surface area of ​​the entire inner walls of the cavities 172, 2π×DMT×THC×(number of cavities 172) (see FIG. 6), and the cross-sectional area of ​​the entire cavities 172, π×DMT 2 The pressure loss of the fluid caused by the static elimination rod 110 is adjusted by × (the number of cavities 172) (see FIG. 7). Therefore, by optimizing the surface area of ​​the entire inner wall of the cavities 172 and the cross-sectional area of ​​the entire cavities 172, static electricity can be removed from the entire fluid while keeping the pressure loss of the fluid low. [Explanation of symbols]

[0035] 100 Anti-static equipment 110 Antistatic rod 111 Tip of static elimination rod 112 Finn 113 Slit 120 Fixed part 121 Annular protrusion 122 Tapered sealing surface 123 flange 124 Handle hole 125 Central axis of fixed part 130 Union nut 131 Union nut tip 132 Base end of union nut 134 Female thread 135 Stepped section 200 Tea 210 Branch pipe section 211 Branch road 213 Outer Cylinder 214 Inner cylinder 215 Male thread 216 Reverse tapered sealing surface 217 Circular Groove 220 Main pipe section 221 Channel 510, 520 tubes

Claims

1. A device for removing static electricity from fluids in pipes. a static elimination rod that is made of conductive resin, is a member that does not allow the fluid to pass through, is grounded, and is disposed within the flow path in the pipe so as to intersect with the center of the flow path; Equipped with The static elimination rod is disposed at a position where it intersects with the center of the flow path. A cavity that penetrates the static elimination rod parallel to the direction of the flow path. Contains A static eliminator characterized by:

2. The static elimination rod is A plurality of fins, each of which is parallel to the direction of the flow path. Including, The cavity is a slit formed by the plurality of fins. The static eliminator according to claim 1 .

3. If the piping is a manifold, a fastener in the form of a stopcock for removably blocking one branch of said manifold; Further provided with The static elimination rod extends from the fixed portion through the branch path to a position beyond the center of the flow path. The static eliminator according to claim 1 .

4. The static elimination rod is A plurality of fins each extending from within the branch channel to beyond the center of the channel and parallel to the direction of the channel. Including, The cavity is a slit formed by the plurality of fins. The static eliminator according to claim 3.

Images