JP2011064543A - Shunt-type flowmeter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shunt-type flowmeter improving maintainability. <P>SOLUTION: A shunt-type flowmeter includes a main channel 11 through which a fluid flows, a main channel holder 10 provided with shunt holes 4a and 4b communicating with the main channel 11, a shunt channel holder 30 provided with a shunt channel 25 communicating with the main channel 11 via the shunt holes 4a and 4b and attachable to and detachable from the main channel holder 10, opening and closing plates for opening and closing opening parts of the shunt holes 4a and 4b, springs for blocking the opening parts by the opening and closing plates when the shunt channel holder 30 is removed from the main channel holder 10, and protrusion members 32a and 32b for separating the opening parts and the opening and closing plates from each other when the shunt channel holder 30 is attached to the main channel holder 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  Some embodiments according to the present invention relate to measurement technology, and more particularly to a shunt flow meter.

  Conventionally, as a shunt flow meter, a shunt channel (bypass channel) is formed, and a shunt channel holder (bypass channel) configured to be detachable from a main channel holder (main channel module) that forms the main channel A module having a module) is known (for example, see Patent Document 1).

JP-A-2005-300365

  However, in the conventional shunt type flow meter, there is a problem that if the branch channel holder is removed from the main channel holder in a state where the fluid is flowing through the main channel, the fluid leaks from the branch holes communicating with the main channel. Therefore, when removing the branch flow path holding body from the main flow path holding body, it is necessary to stop the fluid flowing through the main flow path, and also stop the device installed downstream of the shunt flow meter. Ease of use).

  Some aspects of the present invention have been made in view of the above-described problems, and an object of the present invention is to provide a shunt flow meter that can improve maintainability.

  A shunt flow meter according to the present invention is provided with a main flow path holding body provided with a main flow path through which a fluid flows and a shunt hole communicating with the main flow path, and a shunt flow path communicating with the main flow path through the shunt holes, A diversion channel holding body that can be attached to and detached from the main flow path holding body, an opening and closing plate for opening and closing the opening in the diversion hole, and an opening and closing plate that closes the opening when the diversion channel holding body is removed from the main flow path holding body And an protruding member that separates the opening and the opening / closing plate when the branch flow path holding body is attached to the main flow path holding body.

  According to such a configuration, the opening is closed by the opening / closing plate when the branching channel holder is removed from the main channel holding member, and the opening and the switching plate are connected when the branching channel holder is attached to the main channel holder. Separate. Thereby, since the opening part of a diversion hole opens at the time of attachment of a diversion flow path holding body, a main flow path and a diversion flow path are connected via a diversion hole, and a fluid distribute | circulates between a main flow path and a diversion flow path. On the other hand, since the opening of the diversion hole is closed when the diversion channel holder is removed, the flow of fluid between the main flow channel and the diversion channel is hindered, and the fluid flowing through the main flow channel is prevented from leaking from the diversion hole. Can do.

  Preferably, the elastic body urges one surface of the opening / closing plate so that the opening / closing plate closes the opening, the protruding member is provided on the branch flow path holding body, and the branch flow path holding body serves as the main flow path holding body. When attached, force is applied to the other side of the opening / closing plate.

  Preferably, the opening is formed by an annular spacer.

  Preferably, the opening / closing plate has a diameter larger than the inner diameter of the spacer and smaller than the diameter of the opening.

  According to this configuration, the opening / closing plate has a diameter larger than the inner diameter of the spacer and smaller than the diameter of the opening. As a result, the opening / closing plate is securely locked by the spacer and can move inside the flow dividing hole.

  Preferably, the opening / closing plate is made of rubber.

  According to this configuration, the opening / closing plate is made of rubber. Thereby, the sealing property of an opening part can be improved and a fluid can be interrupted | blocked reliably.

  Preferably, the elastic body is a spring.

  According to the shunt flow meter of the present invention, the opening of the shunt hole is opened when the shunt holder is attached, so that the main channel and the shunt channel communicate with each other via the shunt hole, Fluid flows between them. On the other hand, since the opening of the diversion hole is closed when the diversion channel holder is removed, the flow of fluid between the main flow channel and the diversion channel is hindered, and the fluid flowing through the main flow channel is prevented from leaking from the diversion hole. Can do. Thereby, when the fluid is flowing through the main flow path, the branch flow path holding body can be removed from the main flow path holding body, and the maintainability can be improved.

It is a perspective view of a shunt type flow meter in one embodiment of the present invention. FIG. 2 is a side sectional view of the shunt flow meter shown in FIG. 1. FIG. 2 is a top view of the main channel holder shown in FIG. 1. FIG. 4 is a cross-sectional view taken along the line III-III shown in FIG. 3. FIG. 4 is a cross-sectional view in the direction of arrows IV-IV shown in FIG. 3. FIG. 2 is a bottom view of the branch passage holder shown in FIG. 1. FIG. 3 is a perspective view of the flow sensor shown in FIG. 2. FIG. 8 is a cross-sectional view taken along the line VII-VII shown in FIG. 7. It is an expanded side sectional view explaining the state of a diversion hole at the time of removal of a diversion flow path holding body. It is an expanded side sectional view explaining the state of a diversion hole at the time of attachment of a diversion channel holder.

  Embodiments of the present invention will be described below. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  1 to 10 show an embodiment of a shunt flow meter according to the present invention. FIG. 1 is a perspective view of a shunt flow meter according to an embodiment of the present invention. As shown in FIG. 1, the shunt flow meter 1 includes a main flow path holding body 10 provided with a main flow path 11 and a diversion flow path holding body 30 that can be attached to and detached from the main flow path holding body 10. In addition, the shunt flow meter 1 includes a display device 35 disposed on the upper part of the shunt passage holder 30. The display device 35 includes a light emitter such as an LED, a liquid crystal display, and the like.

  FIG. 2 is a side sectional view of the shunt flow meter shown in FIG. The branch channel holder 30 is provided with a branch channel 25, and the shape of the branch channel holder 30 is, for example, a plate shape or a block shape. Further, the branch flow path holding body 30 includes a flow sensor 8 and projecting members (shafts) 32a and 32b, which will be described later, a central processing unit (hereinafter referred to as a CPU) 300, an input device 251, and a storage device. 400. The input device 251 has input means such as an input key, and is configured to be able to input various settings and information. The storage device 400 is for storing information relating to a ratio between the flow rate of the fluid flowing through the branch flow path 25 and the flow rate of the fluid flowing through the main flow path 11 (hereinafter referred to as a diversion ratio), and a random access memory (hereinafter referred to as RAM). Volatile memory, etc.). The flow sensor 8, the input device 251, the storage device 400, and the display device 35 are electrically connected to the CPU 300. Further, the CPU 300 has a calculation circuit 301 for calculating the flow rate of the fluid flowing through the main flow path 11. 2 is schematically illustrated, and actually further includes a microprocessor, a RAM, a read only memory (ROM), an I / O circuit, and the like.

  3 is a top view of the main flow path holding body shown in FIG. 1, FIG. 4 is a cross-sectional view taken along the line III-III shown in FIG. 3, and FIG. 5 is an IV shown in FIG. It is -IV line arrow direction sectional drawing. As shown in FIG. 3, an elliptical concave portion 16 is provided on the upper surface of the main flow path holding body 10. The recess 16 is provided with a pair of flow dividing holes 4 a and 4 b that communicate with the main flow path 11. That is, as shown in FIG. 5, the flow dividing hole 4 a penetrates from the bottom surface of the recess 16 to the inner wall (inner surface) of the main flow path 11. Although not shown, the flow dividing hole 4b similarly penetrates from the bottom surface of the recess 16 to the inner wall (inner surface) of the main flow path 11. As a result, as shown in FIG. 4, the flow dividing holes 4 a communicate with the upstream of the main flow path 11 from the concave portion 16, and the flow dividing holes 4 b communicate with the downstream of the main flow path 11 from the concave portion 16.

  In the hexahedral main flow path holding body 10 shown in FIG. 1, as shown in FIG. 4, an inlet 13 and an outlet 14 are provided on two opposing faces. A pipe (not shown) through which a fluid such as gas or liquid is inserted is inserted into each of the inlet 13 and the outlet 14. The main flow path 11 provided inside the flow path holding body 10 penetrates from the inlet 13 to the outlet 14. The main flow path 11 communicates with piping connected to the inlet 13 and the outlet 14, and the fluid that flows in from the inlet 13 flows out from the outlet 14. A part of the main channel 11 is provided with a differential pressure generating structure 12 that narrows the inner diameter of the main channel 11. The differential pressure generating structure 12 generates a differential pressure according to the flow rate of the fluid between the inlet 13 side and the outlet 14 side of the main channel 11. The differential pressure generating structure 12 is, for example, an orifice or a venturi. In the present application, the inlet 13 side from the differential pressure generating structure 12 of the main channel 11 is referred to as “upstream”, and the outlet 14 side of the differential pressure generating structure 12 of the main channel 11 is referred to as “downstream”. The material of the main channel holder 10 can be metal or resin.

  FIG. 6 is a bottom view of the branch passage holder shown in FIG. As shown in FIG. 2, the branch flow path holding body 30 is disposed so as to cover the recess 16 shown in FIGS. 3 to 5 when the branch flow path holding body 30 is attached to the main flow path holding body 10. The branch channel 25 is provided on the surface facing the main channel holder 10, that is, on the lower surface of the branch channel holder 30 as shown in FIG. 6. The branch channel 25 is a recess having the same or substantially the same contour as the elliptical recess 16 shown in FIGS. As shown in FIG. 2, the branch channel 25 communicates with the main channel 11 via the pair of branch holes 4 a and 4 b. Note that when the branch flow path holding body 30 is attached to the main flow path holding body 10, the concave portion 16 covered with the branch flow path holding body 30 may form a part of the branch flow path 25. The branch channel 25 includes a pair of projecting members 32 a and 32 b respectively disposed on the pair of branch holes 4 a and 4 b when the branch channel holder 30 is attached to the main channel holder 10, and a fluid flowing through the branch channel 25. And a flow sensor 8 for detecting the flow rate of.

  7 is a perspective view of the flow sensor shown in FIG. 1, and FIG. 8 is a cross-sectional view in the direction of arrows VII-VII shown in FIG. As shown in FIGS. 7 and 8, the flow sensor 8 includes a substrate 60 provided with a cavity 66, an insulating film 65 disposed on the substrate 60 so as to cover the cavity 66, and a heater 61 provided on the insulating film 65. The upstream side resistance thermometer element 62 provided on the upstream side of the heater 61, the downstream side resistance thermometer element 63 provided on the downstream side of the heater 61, and the upstream side of the upstream temperature sensor element 62. An ambient temperature sensor 64 is provided.

  A portion of the insulating film 65 shown in FIG. 8 that covers the cavity 66 forms a heat insulating diaphragm. The ambient temperature sensor 64 measures the temperature of the fluid flowing into the branch channel 25 shown in FIG. The heater 61 shown in FIGS. 7 and 8 is disposed at the center of the insulating film 65 covering the cavity 66, and the fluid flowing through the branch flow path 25 has a constant temperature, for example, 10 ° C., than the temperature measured by the ambient temperature sensor 64. Heat to increase. The upstream temperature measuring resistance element 62 is used for detecting the temperature upstream of the heater 61, and the downstream temperature measuring resistance element 63 is used for detecting the temperature downstream of the heater 61.

  Here, when the fluid in the branch flow path 25 shown in FIG. 2 is stationary, the heat applied by the heater 61 shown in FIGS. 7 and 8 is diffused symmetrically in the upstream direction and the downstream direction. Accordingly, the temperatures of the upstream resistance temperature element 62 and the downstream resistance temperature element 63 are equal, and the electrical resistances of the upstream resistance temperature element 62 and the downstream resistance temperature element 63 are equal. On the other hand, when the fluid in the branch flow path 25 shown in FIG. 2 flows from upstream to downstream, the heat applied by the heater 61 shown in FIGS. 7 and 8 is carried in the downstream direction. Therefore, the temperature of the downstream side resistance thermometer element 63 becomes higher than the temperature of the upstream side resistance thermometer element 62. Therefore, there is a difference between the electrical resistance of the upstream side resistance thermometer element 62 and the electrical resistance of the downstream side resistance thermometer element 63. The difference between the electrical resistance of the downstream resistance thermometer element 63 and the electrical resistance of the upstream resistance thermometer element 62 has a correlation with the velocity of the fluid in the branch channel 25 shown in FIG. Therefore, the flow rate of the fluid flowing through the shunt flow path 25 is obtained from the difference between the electrical resistance of the downstream temperature measuring resistance element 63 and the electrical resistance of the upstream temperature measuring resistance element 62.

As a material of the substrate 60 shown in FIGS. 7 and 8, silicon (Si) or the like can be used. As a material of the insulating film 65, silicon oxide (SiO ₂ ) or the like can be used. The cavity 66 is formed by anisotropic etching or the like. In addition, platinum (Pt) or the like can be used as the material of the heater 61, the upstream temperature measuring resistance element 62, the downstream temperature measuring resistance element 63, and the ambient temperature sensor 64, and can be formed by a lithography method or the like. is there.

  The flow rate of the fluid flowing through the branch flow path 25 detected by the flow sensor 8 is output to the calculation circuit 301 of the CPU 300 shown in FIG. Further, information on the diversion ratio, for example, the value of the diversion ratio, is input from the input device 251 shown in FIG. 2 by a user or an engineer. The shunt ratio value input by the input device 251 is written and stored in the storage device 400 by the calculation circuit 301 of the CPU 300. Note that the information regarding the flow division ratio may be stored in the storage device 400 via a personal computer or the like.

  When the diversion flow meter 1 measures the flow rate of the fluid flowing through the main flow path 11, the calculation circuit 301 reads information about the diversion ratio stored in advance from the storage device 400. Next, the calculation circuit 301 calculates the flow rate of the fluid flowing through the main flow path 11 based on the information related to the diversion ratio read from the storage device 400 and the flow rate of the fluid flowing through the diversion path 25 input from the flow sensor 8. To do. The display device 35 displays information related to the diversion ratio read from the storage device 400 by the calculation circuit 301 and the flow rate of the fluid flowing through the main flow path 11 calculated by the calculation circuit 301.

  FIG. 9 is an enlarged side cross-sectional view for explaining the state of the diversion holes when the diversion channel holder is removed. 9 and 10, only the state of the flow dividing hole 4a is shown, but the state of the flow dividing hole 4b is also the same. Therefore, illustration and description of the state of the diversion holes 4b are omitted. As shown in FIG. 4, a step is provided in each of the flow dividing holes 4 a and 4 b, and the inner diameter of each of the flow dividing holes 4 a and 4 b is connected to the recess 16 on the side connected to the main flow path 11. It is narrower than the side. As shown in FIG. 9, a spring 41, an opening / closing plate 42, and a spacer 43 are installed in the diversion hole 4a. The spring 41 is for moving the opening / closing plate 42 by using an elastic force, and is inserted into the step inside the flow dividing hole 4a from the concave portion 16 side. The opening / closing plate 42 is for opening and closing the opening 5 of the flow dividing hole 4 a and is installed on the spring 41. Thereby, the lower surface of the opening / closing plate 42 is biased upward by the spring 41. The spacer 43 is for forming the opening 5 of the flow dividing hole 4a and has an annular shape. The spacer 43 is press-fitted onto the opening / closing plate 42 from the concave portion 16 side of the flow dividing hole 4a. Thus, the opening / closing plate 42 is fixed by the spring 41 and the spacer 43, and the opening 5 is closed by the opening / closing plate 42.

  FIG. 10 is an enlarged side cross-sectional view for explaining the state of the diversion hole when the diversion channel holder is attached. As shown in FIG. 10, when the branch flow path holding body 30 is attached to the main flow path holding body 10, the protruding member 32 a disposed on the flow dividing hole 4 a comes into contact with the upper surface of the opening / closing plate 42 and applies a force. Thereby, the opening / closing plate 42 is pushed down, and the opening 5 and the opening / closing plate 42 that has closed the opening 5 are separated. When the branch channel holder 30 is removed from the main channel holder 10, the protruding member 32 a is separated from the upper surface of the opening / closing plate 42, and the opening / closing plate 42 is pushed up by the elastic force of the spring 41. As a result, the opening 5 is closed by the opening / closing plate 42 as shown in FIG.

  Thus, the opening 5 is closed by the opening / closing plate 42 when the branching channel holder 30 is removed from the main channel holder 10, and the opening 5 is installed when the branching channel holder 30 is attached to the main channel holder 10. And the opening / closing plate 52 are separated from each other. Thereby, since the opening part 5 of the flow dividing holes 4a and 4b opens at the time of attachment of the flow dividing holder 30, the main flow path 11 and the flow dividing path 25 communicate with each other through the flow dividing holes 4a and 4b, and the main flow path 11 and the flow dividing flow path The fluid flows between 25. On the other hand, since the openings 5 of the flow dividing holes 4a and 4b are closed when the branch flow path holding body 30 is removed, the flow of fluid between the main flow path 11 and the flow path 25 is hindered, and the fluid flowing through the main flow path 11 is separated from the flow path. Leakage from 4a and 4b can be prevented.

  The diameter of the opening / closing plate 42 is preferably larger than the inner diameter of the spacer 43 and smaller than the inner diameter of the flow dividing hole 4 a on the side connected to the main flow path 11. As a result, the opening / closing plate 42 is reliably locked by the spacer 43 and can move inside the flow dividing hole 4a.

  The opening / closing plate 42 is preferably made of rubber. Thereby, the sealing property of the opening part 5 can be improved and a fluid can be interrupted | blocked reliably.

  In addition, by installing the spring 41, the opening / closing plate 42, and the spacer 43 in the flow dividing holes 4a and 4b, the measured value of the flow sensor 8 (the flow rate of the fluid flowing through the flow dividing channel 25) is not affected. As the value of the diversion ratio, values in a state where the spring 41, the opening / closing plate 42 and the spacer 43 are installed in the diversion holes 4a and 4b are input, and the flow rate of the fluid flowing through the main flow path 11 is determined based on the value of the diversion ratio. Calculated.

  In the present embodiment, the openings 5 of the flow dividing holes 4a and 4b are formed by the spacers 43. However, the present invention is not limited to this. For example, the spacers 43 are not provided and the flow dividing holes 4a and 4b have the recesses 16 side. The opening may be formed (processed) so as to protrude inward.

  Thus, according to the flow dividing type flow meter 1 according to the present invention, the opening 5 is closed by the opening / closing plate 42 when the flow dividing body 30 is removed from the main flow path holding body 10, When attached to the main flow path holder 10, the opening 5 and the opening / closing plate 52 are separated from each other. Thereby, since the opening part 5 of the flow dividing holes 4a and 4b opens at the time of attachment of the flow dividing holder 30, the main flow path 11 and the flow dividing path 25 communicate with each other through the flow dividing holes 4a and 4b, and the main flow path 11 and the flow dividing flow path The fluid flows between 25. On the other hand, since the openings 5 of the flow dividing holes 4a and 4b are closed when the branch flow path holding body 30 is removed, the flow of fluid between the main flow path 11 and the flow path 25 is hindered, and the fluid flowing through the main flow path 11 is separated from the flow path. Leakage from 4a and 4b can be prevented. Thereby, when the fluid is flowing through the main flow path 11, the branch flow path holding body 30 can be removed from the main flow path holding body 10, and the maintainability can be improved.

  Further, according to the flow dividing meter 1 according to the present invention, the opening / closing plate 42 has a diameter larger than the inner diameter of the spacer 43 and smaller than the inner diameter of the flow dividing holes 4a and 4b on the side connected to the main flow path 11. As a result, the opening / closing plate 42 is securely locked by the spacer 43 and can move inside the flow dividing holes 4a and 4b.

  Further, according to the shunt flow meter 1 according to the present invention, the opening / closing plate 42 is made of rubber. Thereby, the sealing property of the opening part 5 can be improved and a fluid can be interrupted | blocked reliably.

  The configuration of the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Split flow type flow meter 4a, 4b ... Split flow hole 5 ... Opening part 8 ... Flow sensor 10 ... Main flow path holding body 11 ... Main flow path 25 ... Split flow path 30 ... Split flow path holding body 32a, 32b ... Projection member 41 ... Spring 42 … Opening and closing plate 43… Spacer.

Claims (6)

A main flow path holding body provided with a main flow path through which fluid flows and a diversion hole leading to the main flow path;
A diversion channel communicating with the main channel via the diversion hole is provided, and a diversion channel holder that is detachable from the main channel holder;
An opening and closing plate for opening and closing the opening in the diversion hole;
An elastic body that closes the opening by the opening and closing plate when the branch flow path holding body is removed from the main flow path holding body;
A shunt flow meter comprising: a projecting member that separates the opening and the opening / closing plate when the branch flow path holding body is attached to the main flow path holding body. The elastic body biases one surface of the opening / closing plate so that the opening / closing plate closes the opening,
The projection member is provided on the branch passage holding body, and applies a force to the other surface of the opening / closing plate when the branch passage holding body is attached to the main flow path holding body. The shunt flow meter described in 1. The shunt flow meter according to claim 1 or 2, wherein the opening is formed by an annular spacer. The shunt flow meter according to claim 3, wherein the opening / closing plate has a diameter larger than an inner diameter of the spacer and smaller than a diameter of the opening. The shunt flow meter according to any one of claims 1 to 4, wherein the opening / closing plate is made of rubber. The shunt flow meter according to any one of claims 1 to 5, wherein the elastic body is a spring.

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