JP2018194505A - Flow measurement unit and gas meter using the same - Google Patents

Abstract

To provide a flow measurement unit capable of reducing the size and simplifying the structure of a gas meter with shut-off function.SOLUTION: The flow measurement unit comprises: a flow rate measurement part having a straight tubular measuring flow path 12 which has an introduction part 12a and an outflow part 12b of a fluid to be measured; and a shutoff valve which has a valve seat 17 formed in the introduction part 12a and a valve body 15 abutting on the valve seat 17. By using the flow measurement unit the structure of the gas meter is simplified and is reduced in size.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a flow rate measurement unit that measures a flow rate of a fluid such as a gas, and a gas meter in which the flow rate measurement unit is incorporated.

  As a flow meter such as a gas meter, a so-called electronic meter using an ultrasonic wave or a flow sensor has been put into practical use, and a flow rate measuring unit capable of independently measuring a flow rate and a gas meter using the same have been proposed as applications.

  Further, the gas meter has a built-in shut-off valve for shutting off the gas when there is an abnormality by monitoring the gas flow rate as a safety function.

  FIG. 7 shows such a gas meter. A flow meter 403 is accommodated in a gas meter 400 having an inlet 401 and an outlet 402, and a gas as a fluid to be measured is an introduction part 403a of the flow meter 403. From the lead-out portion 403b connected to the outlet pipe 404. A shutoff valve 405 is connected to the inlet 401, and the gas that has entered from the inlet 401 diffuses into the main body of the gas meter 400 via the passage in the shutoff valve 305, and is introduced to the flow measurement unit 403. 403a (for example, see Patent Document 1).

  As another form, a gas meter 500 having a configuration in which a shutoff valve 502 and a flow rate measurement unit 503 are attached to the middle of a straight pipe 501 as shown in FIG. 6 has been proposed (see, for example, Patent Document 2). ).

JP 2012-18031 A JP 2012-247299 A

  However, in the case of the gas meter described in Patent Document 1, since the flow rate measuring unit 403 and the shutoff valve 405 are separated, the gas diffused into the gas meter 400 via the shutoff valve 405 is flow rate measuring unit from various directions. Since the gas flows into the gas meter 403, it is difficult to make the gas flow into the flow rate measurement unit 403 constant due to the shape and size of the gas meter 400. It was necessary to optimize the shape of the flow rate measurement unit 403 or the flow rate coefficient.

  In the case of the gas meter described in Patent Document 2, since the openings 501a and 501b for attaching the flow rate measurement unit 503 and the shutoff valve 502 to the pipe 501 are separately configured, it is difficult to reduce the size of the gas meter. Alternatively, each of the openings 501a and 501b needs to ensure airtightness against gas leakage, and there is a problem that the seal configuration for this is complicated.

  The present invention solves the above-described conventional problems, and has a shut-off function, enables a stable flow rate measurement regardless of the shape of the built-in gas meter, and enables a reduction in the size of the gas meter. The purpose is to provide.

  In order to solve the above-described conventional problems, a flow rate measurement unit according to the present invention is formed in a flow rate measurement unit having a straight tubular measurement flow path having an introduction portion and a discharge portion for a fluid to be measured, and the introduction portion. And a shut-off valve having a valve body that abuts the valve seat.

  As a result, the gas flow from the shut-off valve to the measurement flow path becomes constant, so that stable flow rate measurement is possible regardless of the shape of the gas meter. Can be realized.

  According to the flow rate measurement unit of the present invention, stable flow rate measurement can be performed regardless of the shape of the gas meter, and the gas meter can be miniaturized by integrating the flow rate measurement function and the cutoff function. .

Side view of the flow rate measurement unit according to Embodiment 1 of the present invention. Sectional drawing of the flow measurement unit in Embodiment 1 of this invention Sectional drawing of the gas meter using the flow measurement unit in Embodiment 1 of this invention Sectional drawing of the gas meter using the flow measurement unit in Embodiment 1 of this invention Sectional drawing of the gas meter using the flow measurement unit in Embodiment 1 of this invention Cross section of the same flow measurement unit Cross section of a gas meter that uses a conventional flow rate measurement unit Cross section of a gas meter that uses a conventional flow rate measurement unit

  According to a first aspect of the present invention, there is provided a flow rate measuring unit having a straight tubular measurement channel including an introduction part and a lead-out part for a fluid to be measured, a valve seat formed in the introduction part, and a valve body that contacts the valve seat A flow measurement unit equipped with a shutoff valve, which enables stable flow measurement regardless of the shape of the gas meter, and miniaturization of the gas meter by integrating the flow measurement function and the shutoff function. I can plan.

  According to a second aspect of the invention, particularly in the first aspect of the invention, the shut-off valve extends from the introduction portion and drives the cylindrical portion having an opening and the valve body fixed inside the cylindrical portion. And a driving device for

  In a third aspect of the invention, particularly in the second aspect of the invention, the drive device is configured to move the valve body by a motor and a linear motion mechanism that converts a rotational motion of the motor into a linear motion. The rotating shaft of the motor, the introduction part, and the lead-out part are arranged substantially linearly.

  4th invention is equipped with the main body provided with the meter inlet and meter outlet of the to-be-measured fluid, and the flow volume measurement unit of any one of 1st-3rd invention, The said derivation | leading-out part is airtight to the said meter outlet. This is a gas meter connected to.

A fifth invention includes a main body in which a meter inlet and a meter outlet of a fluid to be measured are arranged substantially linearly, and a flow rate measuring unit according to any one of the first to third inventions, wherein the derivation unit is The gas meter is hermetically connected to the meter outlet.

  A sixth invention includes a main body in which a meter inlet and a meter outlet of a fluid to be measured are arranged substantially linearly, and a flow rate measuring unit according to any one of the first to third inventions, wherein the opening is The gas meter is hermetically connected to the meter inlet.

  Hereinafter, embodiments of a flow rate measurement unit and a flow meter according to the present invention will be described with reference to the accompanying drawings. The same components are given the same reference numerals. The description of the components already described is omitted. The present invention is not limited to the embodiments described below.

  In this specification, the gas meter is connected to a pipe for delivering a fluid, and measures the flow rate of the fluid flowing through the pipe. The gas meter incorporates a flow rate measurement unit, and the flow rate measurement unit measures the flow rate of the fluid. That is, it is assumed that the flow rate measurement unit is a part of the gas meter. Hereinafter, the detailed configuration of the flow rate measurement unit will be described first, and then the gas meter in which the flow rate measurement unit is incorporated will be described.

(Embodiment 1)
FIG. 1 is an external side view of the flow rate measuring unit 10, and FIG.

  The flow rate measurement unit 11 includes a measurement channel 12 having a gas introduction unit 12a and a deriving unit 12b that is a fluid to be measured, and a flow rate measurement block 13 that measures the flow rate of the gas flowing through the measurement channel 12.

  The flow rate measurement unit 11 uses a measurement method using ultrasonic waves. Specifically, the flow rate measurement unit 11 uses a pair of ultrasonic transmitters / receivers 13a and 13b and is transmitted from one ultrasonic transmitter / receiver into the measurement channel 12. The ultrasonic wave propagates in the gas, is reflected on the inner wall 12c of the opposing measurement channel 12, is further propagated in the gas, and is measured by the other ultrasonic transmitter / receiver. The gas flow rate is obtained, and finally the gas flow rate is obtained.

  A shutoff valve 14 is configured on the upstream side of the measurement channel 12. The shut-off valve 14 includes a valve body 15, a drive device 19 for the valve body 15, a valve seat 17 formed in the introduction portion 12 a, and a cylindrical portion 18 that holds the drive device 19. The gas 15 is shut off by moving 15 and contacting the valve seat 17. The drive device 19 includes a motor 16 including a stator 16a, a rotor 16b, and a rotary shaft 16c, and a female screw 15a provided on the tip of the rotary shaft 16c. The female screw 15a of the valve body 15 is screwed to rotate the rotary shaft 16c. It consists of a linear motion mechanism that converts to linear motion, and moves the valve body 15.

  Here, the cylindrical portion 18 may be molded with resin integrally with the measurement flow path 12, or may be separately molded with resin and bonded to the measurement flow path 12. Further, a passage through which gas passes is formed as a gap between the inner wall 18a of the cylindrical portion 18 and the outer periphery of the driving device 19, and the gas passes into the measurement flow path 12 through a path as indicated by a white arrow. be introduced. An opening 18b is formed at the gas inlet of the cylindrical portion 18, and the driving device 19 is inserted into the cylindrical portion 18 through the opening 18b, and the flange 16e of the driving device 19 is connected to the fixing portion 18c. It is fixed with screws (not shown).

  As described above, according to the flow rate measurement unit 10 of the present embodiment, since it has a shut-off function, it is possible to realize the functions of measurement and shut-off simply by being incorporated in a gas meter. In addition, since the valve body 15 is located in the vicinity of the upstream portion of the introduction portion 12a of the measurement flow path 12, gas flows uniformly into the measurement flow path 12 due to the rectification effect of the valve body 15, so that stable flow rate measurement is possible. It becomes possible.

  Moreover, even if there is a difference in the flow state of the gas flowing into the flow rate measurement unit 10 due to the difference in the size and shape of the meter internal space, the influence on the flow rate measurement can be mitigated by the rectification effect by the valve body 15, It is possible to cope with various types of gas meters with one flow rate measurement unit 10.

  FIG. 3 shows a cross-sectional view of the flow rate measurement unit 10 incorporated in the gas meter 100. The flow rate measurement unit 10 is built in a gas meter main body 103 having a meter inlet 101 and a meter outlet 102, and an opening 18b is provided in the meter. The connecting member 104 connected to the inlet 101 is connected. In this configuration, the gas that is the fluid to be measured passes through the flow rate measurement unit 10 from the meter inlet 101 via the connecting member 104 and flows out from the meter outlet 102 as indicated by the white arrow.

  As described above, a gas meter with a shut-off function can be easily realized by incorporating the flow rate measurement unit 10 of the present application into a gas meter.

  FIG. 4 shows a gas meter 200 according to another embodiment in which the flow rate measurement unit 10 of the present application is incorporated. The flow rate measurement unit is disposed inside a gas meter main body 203 in which a meter inlet 201 and a meter outlet 202 are linearly arranged. 10 is built in, and the lead-out part 12b of the flow rate measurement unit 10 is directly connected to the meter outlet 202 by the mounting member 20 in an airtight manner.

  According to the gas meter 200 having the above configuration, the gas meter main body can be further downsized as compared with the gas meter 100 shown in FIG. In addition, it becomes possible to attach a gas meter in the middle of the straight pipe, increasing the degree of freedom of installation.

  FIG. 5 shows a gas meter 300 of another embodiment in which the flow rate measurement unit 10 of the present application is incorporated, and a connecting member 30 for connecting the meter inlet 301 to the opening 18b of the flow rate measurement unit 10 is connected. Yes. FIG. 6 is a cross-sectional view of the state in which the connecting member 30 and the meter inlet 301 are joined to the flow rate measuring unit 10. The flow rate measuring unit 10 and the connecting member 30 are airtightly connected by an O-ring 31. The connecting member 30 and the meter inlet 301 are hermetically connected by an O-ring 32.

  According to the gas meter 300 having the above configuration, the gas meter main body can be further downsized as compared with the gas meter 100 shown in FIG. In addition, it becomes possible to attach a gas meter in the middle of the straight pipe, increasing the degree of freedom of installation.

  According to the measuring unit according to the present invention, since the shut-off valve is built in, the gas meter having the shut-off function can be miniaturized.

DESCRIPTION OF SYMBOLS 10 Flow measurement unit 11 Flow measurement part 12 Measurement flow path 12a Introduction part 12b Derivation part 14 Shut-off valve 15 Valve body 16 Motor 17 Valve seat 18 Cylindrical part 18b Opening part 19 Drive device 100,200,300 Gas meter 101,201,301 Meter inlet 102, 202, 302 Meter outlet

Claims (6)

A flow rate measurement unit having a straight tubular measurement channel having an introduction part and a lead-out part for the fluid to be measured;
A shut-off valve having a valve seat formed in the introduction portion and a valve body that contacts the valve seat;
A flow measurement unit with The said cutoff valve was provided with the cylindrical part extended from the said introducing | transducing part and having an opening part, and the drive device which drives the said valve body fixed inside this cylindrical part. Flow measurement unit. The drive device is configured to move the valve body by a motor and a linear motion mechanism that converts a rotational motion of the motor into a linear motion,
3. The flow rate measurement unit according to claim 2, wherein the opening, the rotation shaft of the motor, the introduction part, and the lead-out part are arranged substantially linearly. A main body having a meter inlet and a meter outlet of the fluid to be measured;
Any one flow rate measurement unit according to claims 1 to 3,
With
A gas meter in which the lead-out portion is hermetically connected to the meter outlet. A main body in which the meter inlet and the meter outlet of the fluid to be measured are arranged substantially linearly;
Any one flow rate measurement unit according to claims 1 to 3,
With
A gas meter in which the lead-out portion is hermetically connected to the meter outlet. A main body in which the meter inlet and the meter outlet of the fluid to be measured are arranged substantially linearly;
Any one flow rate measurement unit according to claims 1 to 3,
With
A gas meter in which the opening is hermetically connected to the meter inlet.

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