JP2012078223A - Flow detection unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow detection unit that is capable of preventing liquid leakage without an operator.SOLUTION: A flow detection unit for detecting flow of liquid through a tube comprises a tube, a flow meter for detecting flow of liquid through the tube, and a connection member for connecting the tube and the flow meter. The flow meter includes a cylindrical body having a tapered inner peripheral surface, the cross-sectional area of which gets wider from a flow-in end toward a flow-out end, a float provided in the cylindrical body, a male screw part formed on an outer peripheral end of the cylindrical body, and an O ring that is provided on an end surface of the outer peripheral end and slightly protruded from the end surface. The connection member has a fixed end fixed to an end of the tube and a connection end connected to the flow meter. The connection end has a female screw part that engages with the male screw part of the flow meter and a contact end face with which the O ring is tightly brought into contact by engagement between the male screw part of the flow meter and the female screw part.

Description

  The present invention relates to a flow rate detection unit that detects a flow rate of a fluid flowing in a pipe.

  A workpiece such as a semiconductor wafer having a plurality of semiconductor devices such as IC and LSI formed on the front surface is ground to a predetermined thickness by a grinding device, and the back surface is polished by a polishing device as necessary. Then, after the fine grinding distortion caused by grinding is removed, it is cut by a cutting device and divided into individual semiconductor devices. The divided semiconductor devices are widely used in electric devices such as mobile phones and personal computers.

  Occurs in a processing device such as a grinding device, a polishing device, or a cutting device, a constant temperature processing water supply device that supplies processing water at a constant temperature to the processing device (for example, see Japanese Patent Application Laid-Open No. 2007-127343), or a processing device. In peripheral devices such as a processing waste liquid treatment apparatus (see, for example, Japanese Patent Application Laid-Open No. 2009-95941) that processes the processed waste liquid, and a pure water generation apparatus that generates pure water as processing water to be supplied to the processing apparatus, And various pipes through which the waste fluid flows, and a flow meter for measuring the flow rate in the pipes.

  As the flow meter, a float type (floating type) area flow meter is generally used, and a threaded connection between conical surfaces is adopted for connection between the flow meter and a pipe through which a fluid flows. That is, a conical male screw (tapered screw) is formed at the end of the tube, and a nut having a conical female screw corresponding to the male screw is rotatably attached to the end of the flowmeter, and the nut is rotated, The pipe and the flow meter are connected by screwing the female screw into the male screw.

  In order to prevent liquid leakage during connection, a sealing tape is wound around the conical (tapered) male screw in advance so that a slight gap between the male screw and the female screw is filled. Yes.

JP 2007-127343 A JP 2009-95941 A

  However, the number and manner of winding of the sealing tape and the tightening condition of the taper screw are different depending on the operator. There was a problem that liquid leakage occurred.

  The present invention has been made in view of these points, and an object of the present invention is to provide a flow rate detection unit capable of preventing liquid leakage regardless of the operator.

  According to the present invention, there is provided a flow rate detection unit for detecting a flow rate of a liquid flowing in a pipe, wherein the pipe, a flow meter for detecting a flow rate of the liquid flowing in the pipe, and the pipe and the flow meter are connected. A connecting member, and the flowmeter includes a cylindrical main body having a tapered inner peripheral surface whose cross-sectional area increases from the inflow end toward the outflow end, a float accommodated in the main body, A male screw portion formed at the outer peripheral end portion, and an O-ring disposed on the end face in a state of slightly protruding from the end face of the outer peripheral end portion, and the connecting member is fixed to the end portion of the pipe A fixed end portion and a connection end portion connected to the flow meter, the connection end portion including a female screw portion to which the male screw portion of the flow meter is screwed, and the male screw portion of the flow meter being the A flow rate detecting unit characterized by having a contact end face to which the O-ring is press-contacted by being screwed into a female screw part. Tsu door is provided.

  In the flow rate detection unit of the present invention, the O-ring is pressed against the contact end surface to seal the joint between the pipe and the flow meter, so that no liquid leakage occurs and the operator may be affected. Absent.

1A is an external perspective view of the flow meter, and FIG. 1B is a partially enlarged side view thereof. It is a typical longitudinal section showing the principle of a flow meter. It is a front view of a flowmeter detection unit. It is an expanded sectional view of the connection part of a pipe and a flow meter.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1A, an external perspective view of the flow meter 10 is shown. FIG. 1B is a partially enlarged side view thereof, and FIG. 2 is a schematic longitudinal sectional view for explaining the principle.

  As shown in the longitudinal sectional view of FIG. 2, the cylindrical main body 12 of the flow meter 10 has a tapered inner peripheral surface 15 whose cross-sectional area increases from the fluid inflow end 12a to the outflow end 12b. Since the outer peripheral surface 13 of the cylindrical main body 12 is formed into a cylindrical surface, the thickness of the cylindrical main body 12 is formed so as to continuously decrease from the inflow end 12a to the outflow end 12b.

  The cylindrical main body 12 is made of a transparent resin such as polycarbonate. A float (floating element) 22 that can freely move up and down is accommodated in a flow path 19 defined by a tapered inner peripheral surface 15 of the cylindrical main body 12.

  When a fluid (liquid, gas, vapor) flows in the flow path 19 of the flow meter 10 from the lower inflow end 12a toward the upper outflow end 12b, the float 22 is caused by a force due to a pressure difference generated before and after that. Pushed up.

  As the float 22 moves upward, the flow area between the float 22 and the tapered inner peripheral surface 15 increases, so the speed of the fluid passing therethrough decreases and the pressure difference decreases, so that the float 22 has its movable part. It rests at a balanced position between the mass and the pressure difference.

  Since the flow area determined by the position of the float 22 at this time and the flow rate passing therethrough are in a fixed relationship, the flow rate of the fluid is determined by detecting the position of the flow and 22 using the scale 17 formed on the outer periphery 13 of the cylindrical body 12. To detect.

  As shown in FIG. 1A, male screw portions 14 are formed at both ends of the outer periphery of the cylindrical main body 12. Further, as best shown in FIG. 1B, an O-ring 18 is provided so as to slightly protrude from the end face 16. An O-ring similar to the O-ring 18 is disposed on the lower end surface of the cylindrical main body 12, and an opening communicating with the flow path 19 is formed.

  Referring to FIG. 3, a front view of the flow rate detection unit 25 of the embodiment of the present invention is shown. The flow rate detection unit 25 includes a pipe 24 through which a fluid such as pure water flows, a flow meter 10 that detects a flow rate of the fluid flowing through the pipe 24, and a connection member (adapter) 28 that connects the pipe 24 and the flow meter 10. Consists of

  As best shown in the partial cross-sectional view of FIG. 4, the connection member 28 has a fixed end 28 a fixed to the end of the tube 24 and a connection end 28 b connected to the flow meter 10. Yes. A male screw portion 26 is formed at the protruding end portion of the tube 24, and a female screw portion 29 into which the male screw portion 26 is screwed is formed at the fixed end portion 28 a of the connection member 28.

  When the internal thread portion 29 formed on the fixed end portion 28 a of the connecting member 28 is screwed into the external thread portion 26 of the tube 24 and tightened, an O-ring 30 provided on the outer periphery of the proximal end portion of the external thread portion 26 of the tube 24 is formed. The fluid is sealed by pressing between the end face of the connecting member 28 and the end of the tube 24.

  Similarly, an internal thread portion 31 into which the external thread portion 14 of the flow meter 10 is screwed is formed at the connection end portion 28 b of the connection member 28. When the male screw portion 14 of the flow meter 10 is screwed and tightened to the female screw portion 31 formed at the connection end portion 28 b of the connection member 28, the O-ring 18 disposed on the end surface 16 of the flow meter 10 is crushed and the flow meter is collapsed. 10 end surfaces 16 and the contact end surface 33 of the connecting member 28 are pressed against each other to seal the fluid passing therethrough.

  Referring again to FIG. 3, the upper end of the flow meter 10 and the pipe 32 are connected by a connection member 34 having the same structure as the connection member 28. That is, the connection member 34 has a fixed end 34a and a connection end 34b, and is connected to the pipe 32 at the fixed end 34a and connected to the flow meter 10 at the connection end 34b.

  According to the flow rate detection unit 25 of the above-described embodiment, the O-ring 18 is pressed against the end face 16 of the flow meter 10 and the contact end face 33 of the connection member 28 to seal the joint, and thus liquid leakage occurs at the joint. In addition, the sealing performance is not affected by the operator.

DESCRIPTION OF SYMBOLS 10 Flowmeter 12 Cylindrical main body 14 Male thread part 15 Tapered inner peripheral surface 16 End surface 18 O-ring 19 Flow path 22 Float 24, 32 Pipe 28, 34 Connection member 28a, 34a Fixed end part 28b, 34b Connection end part 31 Female thread part 33 Contact end face

Claims (1)

A flow rate detection unit for detecting a flow rate of a liquid flowing in a pipe,
A pipe, a flow meter for detecting the flow rate of the liquid flowing in the pipe, and a connecting member for connecting the pipe and the flow meter,
The flow meter is formed at a cylindrical main body having a tapered inner peripheral surface whose cross-sectional area increases from an inflow end toward an outflow end, a float accommodated in the main body, and an outer peripheral end of the main body. A male screw part, and an O-ring disposed on the end face in a state slightly protruding from the end face of the outer peripheral end part,
The connection member includes a fixed end fixed to the end of the pipe, and a connection end connected to the flow meter,
The connection end portion has a female screw portion into which the male screw portion of the flow meter is screwed, and a contact end surface to which the O-ring is pressed against when the male screw portion of the flow meter is screwed into the female screw portion. A flow rate detection unit characterized by

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