JP2019152491A - Gas meter - Google Patents

Abstract

To provide a gas meter with which it is possible to reduce the number of screws used in assembly while securing the airtightness of a sealed space that is required for the measurement of a gas flow rate.SOLUTION: Provided is a gas meter 1 for measuring the flow rate of a gas in the process of a gas having flowed into a sealed space from a gas inflow port 21 reaching a gas outflow port 22 from the gas inflow port 21, comprising: a lid member 12 for forming a sealed space between a housing 11 and itself by fitting to the inner face of the housing 11; a screw hole 12b for detachment which is formed in the lid member 12; a screw hole 31b for attachment which counter-contacts the screw hole 12b for detachment on the inside of the housing 11, the diameter of which is smaller than the hole diameter of the screw hole 12b for detachment; and a screw 41 for attachment which is screwed into the screw hole 31b for attachment penetrating through the screw hole 12b for detachment.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas meter for measuring a gas flow rate.

  Usually, a gas meter is provided with a gas inlet connected to a gas supply source and a gas outlet connected to a gas device such as a combustor. Thereby, in the gas meter, the flow rate of the gas flowing in from the gas inlet can be measured in the process of passing through the series of gas flow paths from the gas inlet to the gas outlet.

  And as a conventional gas meter as mentioned above, it is indicated by patent documents 1, for example.

Japanese Patent No. 6022203

  In the conventional gas meter, the bottom cover is provided at the lower part of the gas meter main body, and the gas flow path is formed by assembling the gas meter main body and the bottom cover in this way. However, in the conventional gas meter, since the gas meter main body and the bottom lid are assembled to face each other, a considerable number of fixing members are required in order to sufficiently crush the seal member provided between them. .

  This invention solves the said subject, and provides the gas meter which can reduce the quantity of the screw used for an assembly | attachment, ensuring the sealing property of the sealed space required for the flow measurement of gas. Objective.

  A gas meter according to the present invention is a gas meter that measures a gas flow rate in a process in which a gas flowing into a sealed space from a gas inlet reaches the gas outlet, and is fitted to an inner surface of a housing. By doing so, the lid member that forms a sealed space with the housing, the removal screw hole formed in the lid member, and the removal screw hole in contact with the inside of the housing, the diameter of the removal screw hole A mounting screw hole having a smaller diameter and a mounting screw that passes through the removal screw hole and is screwed into the mounting screw hole.

  According to the present invention, it is possible to reduce the number of screws used for assembling while securing the sealing property of the sealed space necessary for gas flow rate measurement.

It is the schematic block diagram seen from the front side of the gas meter which concerns on Embodiment 1 of this invention. It is a schematic block diagram seen from the back side of the gas meter which concerns on Embodiment 1 of this invention. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. FIG. 4 is a cross-sectional view taken along arrow IV-IV in FIG. 2. It is sectional drawing corresponding to FIG. 4 when removing a cover member.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG.
1 is a schematic configuration diagram seen from the front side of a gas meter according to Embodiment 1 of the present invention. FIG. 2 is a schematic configuration diagram seen from the back side of the gas meter according to Embodiment 1 of the present invention. In addition, the arrow shown in FIG.1 and FIG.2 represents the flow of gas.

  As shown in FIGS. 1 and 2, the ultrasonic gas meter 1 includes a housing 11, a lid member 12, and a seal member 13. The casing 11 and the lid member 12 constitute a main body of the gas meter 1. The housing 11 is disposed on the back side of the gas meter 1, and the lid member 12 is disposed on the front side of the gas meter 1.

  The housing 11 has an opening that opens toward the front side. The lid member 12 is fitted inside the casing 11 so as to close the opening of the casing 11. The seal member 13 is interposed in a fitting portion between the housing 11 and the lid member 12. As described above, the gas meter 1 has a hollow structure in which the casing 11 and the lid member 12 are fitted together, and the sealed space serving as the internal space is a gas chamber 14 filled with the gas to be measured.

  A gas inlet 21, a gas outlet 22, a flow rate measurement unit 23, a communication member 24, a shutoff valve 25, and a motor 26 are accommodated in the housing 11.

  The gas inflow port 21 and the gas outflow port 22 have a cylindrical shape, penetrate the upper part of the housing 11, and protrude outward from the upper surface of the housing 11. The gas inlet 21 allows the gas supplied from the gas supply source to flow into the gas chamber 14. The downstream opening end of the gas inlet 21 opens toward the back side of the gas meter 1 and communicates with the gas chamber 14. The gas outlet 22 allows the gas whose flow rate is measured by the flow rate measuring unit 23 to flow out toward a gas device such as a combustor.

  The flow rate measurement unit 23 measures the flow rate of the gas flowing in from the gas chamber 14. The flow rate measurement unit 23 has a cylindrical shape and has a measurement flow path 23a therein. The upstream opening end of the measurement flow channel 23 a communicates with the gas chamber 14, while the downstream opening end of the measurement flow channel 23 a communicates with the communication member 24.

  The flow rate measurement unit 23 measures the flow rate in the process in which the gas flowing in from the gas chamber 14 passes through the measurement flow path 23a. Specifically, the flow rate measurement unit 23 has a pair of ultrasonic sensors capable of transmitting and receiving ultrasonic waves, and the gas flow rate is determined based on the propagation time of ultrasonic waves between the pair of ultrasonic sensors. Measure and output the integrated flow rate.

  That is, the gas meter 1 does not directly introduce the gas flowing in from the gas inlet 21 into the measurement flow path 23a, but introduces the gas into the measurement flow path 23a after filling the gas chamber 14 once. As a result, the flow of gas introduced from the gas chamber 14 to the flow rate measuring unit 23 is not disturbed because there is no sudden change in direction compared to the gas flow directly introduced from the gas inlet 21 to the flow rate measuring unit 23. There will be less flow. Therefore, the flow rate measuring unit 23 can measure the gas flow rate with high accuracy.

  The communication member 24 is a bellows member having a cylindrical shape, and communicates the flow rate measurement unit 23 and the gas outlet 22. That is, the communication member 24 can communicate the position shift between the downstream opening end of the flow rate measurement unit 23 and the upstream opening end of the gas outlet 22 by absorbing the expansion and contraction of the bellows. it can.

  The shut-off valve 25 and the motor 26 are provided on the downstream side of the gas inlet 21. The shutoff valve 25 opens and closes the downstream opening end of the gas inlet 21 from the inside of the gas inlet 21. The motor 26 opens and closes the shutoff valve 25 with respect to the downstream opening end of the gas inlet 21 to open and close.

  For example, the shutoff valve 25 moves forward by the forward rotation of the motor 26 in an emergency such as abnormal use of gas or occurrence of an earthquake, and closes the downstream opening end of the gas inlet 21. Thereby, the inflow of gas from the gas inlet 21 to the gas chamber 14 is blocked. Further, the shutoff valve 25 is retracted by reverse rotation driving of the motor 26 during normal use of the gas meter 1, that is, during flow rate measurement, and opens the downstream opening end of the gas inlet 21. Thereby, the inflow of gas from the gas inlet 21 to the gas chamber 14 is released.

  Therefore, when measuring the gas flow rate using the gas meter 1, first, the gas supplied from the gas supply source once flows into the gas chamber 14 from the gas inlet 21. Next, the gas flowing into the gas chamber 14 is introduced into the measurement channel 23 a of the flow rate measurement unit 23. Thereby, the flow measurement part 23 measures the flow volume of the gas which passes the measurement flow path 23a using an ultrasonic wave. Then, the gas whose flow rate is measured by the flow rate measurement unit 23 passes through the communication member 24 and flows out from the gas outlet 22 toward the gas device.

  Next, the assembly structure of the housing 11 and the lid member 12 will be described with reference to FIGS. 3 is a cross-sectional view taken along arrow III-III in FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. FIG. 5 is a cross-sectional view corresponding to FIG. 4 when the lid member is removed.

  As shown in FIGS. 1 and 2, the rectangular lid member 12 is fitted inside the housing 11. Therefore, the four corners on the inner surface of the housing 11 have an R shape (arc shape). On the other hand, the four corners on the outer surface of the lid member 12 have an R shape (arc shape).

  Therefore, when the lid member 12 is fitted inside the housing 11, the slip between the corner of the housing 11 and the corner of the lid member 12 is improved and the frictional force is reduced. Assembly to the body 11 becomes easy. However, among the four corners on the inner surface of the housing 11 and the four corners on the outer surface of the lid member 12, at least four corners on the outer surface of the lid member 12 have an R shape. It is easy to fit the lid member 12 inside the housing 11.

  As shown in FIG. 3, the housing 11 has a folded portion 11a. The folded portion 11 a is a portion that is folded back until the opening end portion of the housing 11 faces the outside of the housing 11 and comes into contact with the outer surface, and covers the entire circumferential direction in the opening portion of the housing 11. Is formed. Thereby, the folding | returning part 11a is improving the intensity | strength in the opening part of the housing | casing 11. FIG.

  On the other hand, the lid member 12 has a flange portion 12a. The flange portion 12 a is formed over the entire circumferential direction at the opening end of the lid member 12. Moreover, the front-end | tip part of the flange part 12a is engaged with the base end part of the folding | returning part 11a. Thereby, the flange part 12a is improving the positioning accuracy of the cover member 12 in the casing depth direction.

  The seal member 13 is interposed between the inner surface of the housing 11 and the outer surface of the lid member 12 over the entire circumferential direction thereof. That is, the seal member 13 seals between the inner surface of the housing 11 and the outer surface of the lid member 12. At this time, the seal member 13 is opposed to the folded portion 11a in the thickness direction, and is disposed along the flange portion 12a.

  As shown in FIGS. 2 and 4, a support member 31 is provided inside the housing 11. The support member 31 is supported on the bottom surface of the housing 11 and extends from the bottom surface toward the opening. Furthermore, the support surface 31 a that is the top surface of the support member 31 is in contact with and supports the back surface of the lid member 12 fitted inside the housing 11. An attachment screw hole 31b is formed in the support surface 31a.

  On the other hand, a screw hole 12b for removal is formed in the lid member 12. The removal screw hole 12b and the attachment screw hole 31b of the support member 31 are in contact with each other in the depth direction of the housing 11 (the front-rear direction of the gas meter 1). The lid member 12 is attached to the housing 11 by the attachment screw 41 penetrating the removal screw hole 12 b being screwed into the attachment screw hole 31 b of the support member 31.

  Here, as shown in FIGS. 4 and 5, the hole diameter of the mounting screw hole 31 b is smaller than the hole diameter of the removing screw hole 12 b, and the shaft diameter of the mounting screw 41 is the removing screw 42. It is smaller than the shaft diameter. The attachment screw 41 can be fastened to the attachment screw hole 31b, and the removal screw 42 can be fastened to the removal screw hole 12b. That is, the attachment screw 41 passes through the removal screw hole 12b without being fastened. Further, the removal screw 42 is not fastened to the attachment screw hole 31b.

  Therefore, when assembling the gas meter 1, first, the gas inlet 21, the gas outlet 22, the flow rate measurement unit 23, the communication member 24, the shutoff valve 25, the motor 26, and the support member 31 are arranged inside the casing 11. Is fixed at a predetermined position.

  Next, the seal member 13 is disposed on the outer surface of the lid member 12 along the flange portion 12a.

  Then, the lid member 12 provided with the seal member 13 is inserted into the inside through the opening of the housing 11. At this time, since the four corners on the inner surface of the housing 11 and the four corners on the outer surface of the lid member 12 that are in contact with each other are in an R shape, the inside of the housing 11 of the lid member 12 Insertion into can be done with a light force compared to when they are not.

  Thereby, the flange portion 12 a of the lid member 12 engages with the proximal end portion of the folded portion 11 a of the housing 11, and the back surface of the lid member 12 abuts on the support surface 31 a of the support member 31. That is, the lid member 12 is positioned in the depth direction of the housing 11.

  Further, the screw hole 12 b for removing the lid member 12 and the screw hole 31 b for attaching the support member 31 are in contact with each other in the depth direction of the housing 11. Furthermore, since the sealing member 13 seals the gap between the inner surface of the housing 11 and the outer surface of the lid member 12, the sealed space formed by the housing 11 and the lid member 12 becomes a gas chamber 14.

  Next, as shown in FIG. 4, the attachment screw 41 is screwed into the attachment screw hole 31b through the removal screw hole 12b. At this time, the attachment screw 41 only passes through the removal screw hole 12b and is not screwed into it. Thereby, the housing | casing 11 and the cover member 12 are fastened.

  When disassembling the gas meter 1, first, the attachment screw 41 is extracted from the attachment screw hole 31 b through the removal screw hole 12 b. Thereby, the fastening between the housing | casing 11 and the cover member 12 is cancelled | released.

  Next, as shown in FIG. 5, the removal screw 42 is screwed into the removal screw hole 12b. Thereby, the front-end | tip part of the screw 42 for removal contacts the support surface 31a, without screwing in the screw hole 31b for attachment of the support member 31. FIG.

  As shown in FIG. 5, when the removal screw 42 is further screwed into the removal screw hole 12b, the removal screw 42 is restricted by the support surface 31a. As the removal screw 42 rotates, it floats from the support member 31. Thereby, the fitting between the inner surface of the housing 11 and the outer surface of the lid member 12 is released, and the lid member 12 is removed from the opening of the housing 11 toward the outside.

  Next, the gas inlet 21, the gas outlet 22, the flow rate measurement unit 23, the communication member 24, the shutoff valve 25, the motor 26, and the support member 31 are removed from the inside of the housing 11 as necessary, and these Replacement or maintenance is performed.

  As described above, the gas meter 1 according to Embodiment 1 of the present invention is formed on the lid member 12 and the lid member 12 that form the gas chamber 14 serving as a sealed space by fitting with the inner surface of the housing 11. The removal screw hole 12b is in contact with the removal screw hole 12b on the inner side of the housing 11, and passes through the attachment screw hole 31b having a diameter smaller than the diameter of the removal screw hole 12b and the removal screw hole 12b. And a mounting screw 41 to be screwed into the mounting screw hole 31b. Thereby, the gas meter 1 can reduce the quantity of the screws used for assembly | attachment, ensuring the sealing property of the sealed space required for the flow volume measurement of gas only by inserting the cover member 12 in the housing | casing 11. FIG. .

  Further, the gas meter 1 is formed with an attachment screw hole 31b, and is screwed into the support surface 31a for supporting the lid member 12 fitted to the inner surface of the housing 11 and the removal screw hole 12b, and into the attachment screw hole 31b. A removal screw 42 that comes into contact with the support surface 31a without being screwed in is provided. Accordingly, the gas meter 1 can remove the lid member 12 from the housing 11 by screwing the removal screw 42.

  Moreover, the gas meter 1 forms the flange part 12a engaged with the housing | casing 11 in the cover member 12, and has arrange | positioned the sealing member 13 along this flange part 12a. Thereby, the gas meter 1 can position the lid member 12 and the seal member 13 with high accuracy in the depth direction of the housing 11.

  Further, the gas meter 1 has a folded portion 11 a formed at the opening end of the housing 11, and a seal member 13 is disposed facing the folded portion 11 a. Thereby, the gas meter 1 can crush the sealing member 13 efficiently only by inserting the cover member 12 in the housing | casing 11 with the folding | returning part 11a which has high rigidity. As a result, the gas meter 1 can improve the sealing performance of the sealed space.

  In the present invention, any constituent element of the embodiment can be modified or any constituent element of the embodiment can be omitted within the scope of the invention.

DESCRIPTION OF SYMBOLS 1 Gas meter 11 Case 11a Folding part 12 Cover member 12a Flange part 12b Removal screw hole 13 Seal member 14 Gas chamber 21 Gas inlet 22 Gas outlet 23 Flow measurement part 23a Measurement flow path 24 Communication member 25 Shut-off valve 26 Motor 31 Support member 31a Support surface 31b Attachment screw hole 41 Attachment screw 42 Removal screw

Claims (5)

A gas meter that measures the flow rate of gas in the process from the gas inlet to the gas outlet when the gas flowing into the sealed space from the gas inlet,
A lid member that forms the sealed space with the housing by fitting with an inner surface of the housing;
A screw hole for removal formed in the lid member;
An attachment screw hole that is in contact with the removal screw hole inside the housing and has a diameter smaller than the diameter of the removal screw hole;
A gas meter comprising: a mounting screw that passes through the removal screw hole and is screwed into the mounting screw hole. The mounting screw hole is formed, and a support surface for supporting the lid member fitted to the inner surface of the housing;
The gas meter according to claim 1, further comprising: a removal screw that is screwed into the removal screw hole and abuts on the support surface without being screwed into the attachment screw hole. The gas meter according to claim 1, further comprising a seal member that seals between an inner surface of the casing and an outer surface of the lid member. The lid member has a flange portion that engages with the housing;
The gas meter according to claim 3, wherein the seal member is disposed along the flange portion. The housing has a folded portion formed by folding the opening end of the housing toward the outside of the housing.
The gas meter according to claim 3, wherein the seal member is disposed to face the folded portion.

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