JP4459734B2 - Gas meter - Google Patents

Description

  The present invention relates to a gas meter. Specifically, the present invention relates to an ultrasonic gas meter that facilitates the work of assembling main members constituting the gas meter.

As a conventional example of an ultrasonic gas meter, there is one in which an ultrasonic transmitter / receiver is arranged in a measurement channel through which a gas flows (see Patent Document 1). The measurement channel is a U-shaped resin pipe member. A pair of through holes facing each other at a predetermined angle are formed on the side wall of the measurement channel. An ultrasonic transmitter and an ultrasonic receiver are fitted into both through holes from the outside of the measurement channel.
Further, the opening portion of the through hole opened in the inner wall surface of the measurement channel is covered with an inflow suppressing body (corresponding to the “turbulent flow suppressing member” in the present invention) which is a plate member. The ultrasonic wave transmitted from the ultrasonic transmitter passes through this inflow suppressor and is received by the ultrasonic receiver. For this reason, the material and shape of the inflow suppressor are set strictly in advance in consideration of the detection sensitivity of the ultrasonic receiver.
The measurement channel is formed by a molding operation in which molten resin is poured into a mold. The assembly operation of the inflow suppressing body is generally performed together with the molding operation of the measurement channel. That is, the inflow suppression body is mounted in advance on the measurement channel mold. And the inflow suppression body is assembled | attached to a measurement flow path by pouring molten resin into a shaping | molding die.
Japanese Patent Laid-Open No. 2003-202254

However, in the above assembling operation, there is a possibility that the inflow suppressing body is deformed by heat at the time of forming the measurement flow path. However, in order to prevent the deformation of the inflow suppressor, it is only necessary to add heat to the inflow suppressor when the measurement channel is formed. That is, the assembly work of the inflow suppressing body may be performed after the molding operation of the measurement channel. However, if both operations are separate operations, it takes time to assemble the gas meter.
The present invention has been devised in view of the above points. That is, the problem to be solved by the present invention is to save time and labor for assembling the gas meter by simultaneously assembling the inflow suppressing member (turbulent flow suppressing member) during the assembling work.

In order to solve the above problems, each invention of the present invention takes the following means.
A gas meter according to a first aspect of the present invention is a gas meter that measures the flow rate of a gas flowing through a measurement flow path using ultrasonic waves, and the measurement flow path is a cylindrical body having a quadrangular cross section and is adjacent to the measurement flow path. A first measurement channel member having a substantially L-shaped cross section that forms two sides and a second measurement channel member having a quadrangular cross section that forms the other two sides adjacent to the measurement channel; A propagation window portion for allowing ultrasonic waves to pass through is formed on the opposing surfaces of the measurement channel member and the second measurement channel member, and the propagation window portion has a propagation window from the inside of the measurement channel. A turbulent flow suppressing member that prevents gas from flowing out from the propagation window by covering the portion is attached, and the turbulent flow suppressing member includes a first measurement flow path member and a second measurement flow path member. A fixed portion is formed at a position corresponding to the contact point with the first measurement flow path member and the second measurement flow path The contact portion sites wood are formed means assembled assembled both each have a configuration using a means of assembling the fixation site of the turbulence suppression member fixed to the contact portion.

In the first aspect of the invention, first, the contact location portions of the first measurement flow path member and the second measurement flow path member are brought into contact with each other and brought into contact (contact). An assembling means is formed at each contact portion. By this assembling means, the measuring flow path members are assembled in contact with each other.
A turbulence suppressing member is assembled to the propagation window portion of the measurement channel. A fixed part is formed in the turbulent flow suppressing member. The fixed portion is disposed at a position facing (corresponding to) a contact portion of each measurement flow path member. And a fixing | fixed site | part is fixed to the contact location of each measurement flow path member using the above-mentioned assembly means. By fixing the fixed part to the contact part, the turbulent flow suppressing member is assembled to the propagation window part.

Next, in the gas meter according to the first aspect of the present invention , the assembling means includes a convex portion provided at one of the contact portions of the first measurement channel member and the second measurement channel member, and the other And a concave portion into which the convex portion provided at one of the contact locations can be inserted. Has been.
In the first invention, a convex portion is formed in one of the contact location portion of the first measurement flow path member and the contact location location of the second measurement flow path member. Further, a concave portion is provided in the other contact portion. By inserting the convex portion into the concave portion, the first measurement flow path member and the second measurement flow path member are assembled.
Moreover, the hole is formed in the fixing | fixed site | part of a turbulent flow suppression member. The fixed part of the turbulent flow suppressing member is fixed to the contact part by inserting the above-described convex part into the hole part.

Then gas meter according to the second aspect of the present invention is the gas meter of the first inventions, the measurement flow path is provided with a rectifying plate that adjust the flow of gas rectifying plates, the turbulence suppression from the interior side of the measurement flow path The member is disposed at a position where the member is pressed against the measurement channel.
In the second invention, the rectifying plate presses the turbulent flow suppressing member in the attached state from the inside of the measurement channel to the measurement channel.

Then gas meter according to the third aspect, in the first aspect or gas meter according to the second inventions, it is possible fit the turbulence suppression member, and the interior of the measurement flow path turbulence suppression member during fixed state The first measurement flow path member and the second measurement flow path member are formed with recessed portions having a shape in which the surface facing the side and the surface on the inner side of the measurement flow path where the propagation window portion is formed are substantially in the same plane. Yes.
In 3rd invention, the turbulent flow suppression member at the time of an attachment state is engage | inserted by the recessed part position formed in the 1st measurement flow path member and the 2nd measurement flow path member. In this state, the surface on the inner side of the measurement channel where the propagation window is formed and the surface of the turbulent flow suppressing member facing the inner side of the measurement channel are substantially in the same plane.

According to the present invention described above, the following effects can be obtained.
First, according to the first aspect, each measurement channel member is brought into contact with the fixed portion of the turbulent flow suppressing member arranged at a position corresponding to the contact location of each measurement channel member. At this time, the assembling means assembles each measurement flow path member and also fixes the fixed part to the contact part. For this reason, a turbulent flow suppression member will be assembled | attached to a propagation window part simultaneously with the assembly | attachment operation | work of each measurement flow path member. For this reason, compared with the case where the assembly operation | work of each measurement flow path part and the assembly operation of a turbulent flow suppression member are performed separately, the work time concerning the assembly operation | work of a measurement flow path can be shortened. As a result, it is possible to save time and labor for assembling the gas meter even if the assembly operation of the turbulent flow suppressing member and the molding operation of the measurement flow path are performed separately.
According to the first invention, the convex portion, which is an assembling means for each measurement channel member, can also be used as an assembling means for the turbulent flow suppressing member .

Next, according to the second invention, the rectifying plate is pressed against the measurement flow channel from the inside of the measurement flow channel to prevent the turbulent flow suppression member from being displaced in the measurement flow channel inward direction or To reduce.
Next, according to the third invention, the surface on the inner side of the measurement flow path where the propagation window is formed and the surface of the turbulent flow suppressing member facing the inner side of the measurement flow path are substantially the same plane. For this reason, gas can be flowed smoothly compared with the case where there exists a level | step difference between the said surface of a measurement flow path, and the said surface of a turbulent flow suppression member.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is an external view of a gas meter, FIG. 2 is an internal structure diagram of the gas meter, and FIGS. 3 to 7 are diagrams of each component of the gas meter.
The gas meter 1 according to the present embodiment is a device for measuring a gas flow rate using ultrasonic waves. The gas meter 1 measures the flow rate of the gas flowing in a measurement tube 30 (see FIG. 4) described later disposed therein. A turbulent flow suppressing member 60 described later is disposed inside the measurement tube 30. The turbulent flow suppressing member 60 and the measuring tube 30 have a configuration in which an assembling operation for assembling each other is easy.

[Gas meter appearance]
The gas meter 1 of FIG. 1 is a substantially rectangular box. As shown in the figure, a gas supply source inlet 3 and a gas facility outlet 5 are provided above the gas meter 1.
A gas supplied from a gas company or the like as a gas supply destination flows into the gas meter 1 from the gas supply source inlet 3. The gas whose gas flow rate is measured in the gas meter 1 flows out from the gas facility outlet 5 and is supplied to facilities and facilities that use the gas.

Display means 7 for displaying the integrated value of the gas flow rate and the like is provided on the front of the gas meter 1. The display content of the display means 7 can be changed as appropriate with a switching switch (not shown).
A communication terminal (not shown) is disposed inside the portion covered with the terminal cover 9. By connecting a communication device (not shown) to the communication terminal, the gas meter 1 can be operated by a signal sent from the communication device.

[Inside gas meter]
A first gas flow path 10, a gas flow rate measurement flow path 20, and a second gas flow path 15 are formed inside the gas meter 1 of FIG. 2. Each flow path communicates within the gas meter 1, and a passage through which gas passes is formed in a substantially U shape as viewed in the figure.
The gas that has flowed into the gas meter 1 from the gas supply source inlet 3 passes through the first gas flow path 10 and flows into the gas flow rate measurement flow path 20. The flow rate of the gas flowing into the gas flow rate measurement channel 20 is measured using ultrasonic waves. The gas whose flow rate is measured flows out of the gas facility outlet 5 through the second gas flow path 15 to the outside.

  The pressure of the gas flowing into the gas meter 1 is measured by a pressure sensor 15 a provided in the second gas flow path 15. The first gas flow path 10 is provided with a shutoff valve 10a. And when abnormality is detected by the pressure sensor 15a, the cutoff valve 10a moves to the left direction seeing in FIG. 2, and the 1st gas flow path 10 is interrupted | blocked. As an abnormality detected, for example, the gas pressure may exceed a preset pressure range.

[Gas flow measurement channel]
The gas flow measurement channel 20 of FIG. 3 includes a main body case 21 and a measurement tube 30.
The main body case 21 includes an upper lid member 21a and a bottom lid member 21b.
The upper lid member 21 a is a box that forms the outer shape of the main body case 21. Openings 22 and 23 are formed in the upper part of the upper lid member 21a so as to communicate the inside of the main body case 21 and each gas flow path. Two sensor storage portions 25 for assembling two ultrasonic transmission / reception sensors (not shown) are formed on both side surfaces of the upper lid member 21a. The two sensor storage portions 25, 25 are opposed to each other with a predetermined angle θ with respect to the gas flow direction (the direction indicated by the arrow in the figure).
By fitting a flat bottom cover member 21b into the upper cover member 21a, a body case 21 having a hollow interior is formed. A measuring tube 30 is accommodated in the main body case 21.

[Measurement tube]
The measuring tube 30 in FIG. 3 is a tube member having a substantially rectangular cross section including four sides of a first side wall portion 30l, a second side wall portion 30r, an upper surface portion 30u, and a bottom surface portion 30d.
The measurement tube 30 in FIG. 4 includes a first measurement tube member 40, a second measurement tube member 50, a turbulent flow suppressing member 60, and a rectifying plate 70.
The first measurement tube member 40 and the second measurement tube member 50 are members that constitute the outer portion of the measurement tube 30. The turbulent flow suppressing member 60 is disposed on the inner wall side of each of the side wall portions 30 l and 30 r of the measuring tube 30. Note that the turbulent flow suppressing member 60 disposed on the second side wall 30r side is not shown for convenience.
Further, the current plate 70 is bridged to the side wall portions 30l and 30r.
Hereinafter, each component will be described.

[First measuring tube member, second measuring tube member]
The first measurement tube member 40 and the second measurement tube member 50 in FIG. 4 are long plate members having a substantially L-shaped cross section. The first measuring tube member 40 constitutes two surfaces, the first side wall portion 30l and the bottom surface portion 30d described above (see FIG. 3). The second measuring tube member 50 constitutes two surfaces, a second side wall portion 30r and an upper surface portion 30u (see FIG. 3).
A first sensor hole 41 is formed in the first side wall portion 30l. A groove 85 is formed on the inner wall surface of the first side wall 30l. A second sensor hole 52 is formed in the second side wall 30r. A groove portion 85 is formed on the inner wall surface of the second side wall portion 30r.

First, the first sensor hole 41 and the second sensor hole 52 are substantially rectangular through holes penetrating the side wall portions 30l and 30r.
The first sensor hole 41 is formed on the left side of the first side wall portion 30l as viewed in FIG. The second sensor hole 52 is formed on the right side of the second side wall portion 30r as seen in the figure. Therefore, the sensor holes 41 and 52 face each other with a predetermined angle θ when the measuring tube 30 is assembled. The pair of ultrasonic transmission / reception sensors housed in the sensor housing portions 25, 25 face the inside of the measurement tube 30 through the sensor holes 41, 52.

  Further, a turbulent flow suppressing member 60 described later is attached to each sensor hole 41, 52 from the inner wall side of each side wall portion 30l, 30r. For this reason, the circumference | surroundings of each sensor hole 41 and 52 in which the turbulent flow suppression member 60 is arrange | positioned are formed in concave shape toward the thickness direction of each side wall part 30l and 30r. The concave portion serves as a storage portion 45 that stores the turbulent flow suppressing member 60. The storage portions 45 and 45 shown in FIG. 4 are concave portions each having a substantially rectangular front shape, and have a shape in which a turbulent flow suppressing member 60 described later can be fitted. Further, the recess size of the storage portions 45, 45 is set to be substantially the same as the thickness of the turbulent flow suppressing member 60.

Next, the groove 85 is a groove that runs parallel to the bottom surface 30d. Three grooves 85 are formed in the first side wall 30l. Further, three groove portions 85 that run parallel to the upper surface portion 30u are formed in the second side wall portion 30r. The groove 85 is formed across the sensor holes 41 and 52. The length of the groove 85 is set to be longer than the interval between the sensor holes 41 and 52 described above.
The groove part 85 formed in the first side wall part 30l and the groove part 85 formed in the second side wall part 30r face each other when the measuring tube 30 is assembled. Then, using the two groove portions 85 facing each other, a later-described rectifying plate 70 is bridged and fixed.
Incidentally groove 85 end portions of the respective side wall portions 30l, holes that penetrate in the thickness direction of 30r (not shown.) Is provided. When the rectifying plate 70 is bridged and fixed, a protruding portion 72 described later formed on the rectifying plate 70 is fitted.

Next, a protruding member 90 is formed above the first side wall portion 30l. The protruding members 90 have a cylindrical shape and are formed six above the first side wall portion 30l. The six projecting members 90 are formed in parallel with the bottom surface portion 30d and are arranged at a predetermined interval from each other. One of the projecting members 90 is formed at an upper position of the first sensor hole 41. Also, six projecting members 90 are formed below the second side wall portion 30r in parallel to the upper surface portion 30u. One of the projecting members 90 is formed at a lower position of the second sensor hole 52.
An insertion hole 80 is formed at the edge of the long side of the bottom surface portion 30d. The insertion hole 80 is a hole having a size into which the above-described protruding member 90 can be inserted. As shown in FIG. 4, six insertion holes 80 are formed at positions corresponding to the above-described protruding members 90.
Six insertion holes 80 are also formed at the edge of the long side of the upper surface portion 30u.

[rectifier]
The rectifying plate 70 is a member for adjusting the gas flow in the measuring tube 30.
The rectifying plate 70 in FIG. 4 is a substantially flat plate member. The shape of the rectifying plate 70 is rectangular when viewed from above. The length of the long side of the current plate 70 is substantially the same as the length of the groove 85 described above. For this reason, the current plate 70 fitted in each of the sensor holes 41 and 52 described above is disposed across the sensor holes 41 and 52.
Further, projecting portions 72 projecting in the short direction are formed at the four corners of the current plate 70. When the rectifying plate 70 is fitted into the groove 85, the protruding portion 72 is inserted into the holes at both ends of the groove 85 for positioning.

[Turbulent member]
The turbulent flow suppressing member 60 is a member necessary for the gas flowing in a predetermined direction (see FIG. 3) to flow smoothly without generating vortices or the like. That is, the turbulent flow suppression member 60 is a member that prevents gas from flowing in and out of the sensor holes 41 and 52 described above. A predetermined flow rate measurement accuracy can be maintained by smoothly flowing the gas through the measurement tube 30.
The turbulent flow suppressing member 60 in FIG. 5 is a substantially flat plate member, and has a size that covers the sensor holes 41 and 52 described above. Moreover, the turbulent flow suppressing member 60 forms a fixed portion 61 whose upper portion protrudes in a convex shape as seen in FIG. An attachment hole 62 that penetrates the turbulent flow suppressing member 60 in the thickness direction is formed in the fixed portion 61. The mounting hole 62 has a diameter into which the above-described protruding member 90 (see FIG. 4) can be inserted. In the state where the turbulent flow suppressing member 60 is disposed in each sensor hole 41, 52, the mounting hole 62 faces the above-described protruding member 90.

  In addition, a fine hole is formed in the ultrasonic wave passing portion 63 located in the central portion of the turbulent flow suppressing member 60. The ultrasonic waves transmitted from one ultrasonic transmitter / receiver are transmitted into the measurement tube 30 through the fine holes of the turbulent flow suppressing member 60 attached to the first sensor hole 41. The transmitted ultrasonic wave passes through the fine hole of the turbulent flow suppressing member 60 attached to the second sensor hole 52 and is received by the other ultrasonic transceiver. For this reason, the fine holes of the ultrasonic wave passing portion 63 are set to the optimum shape, size, and interval in consideration of the detection sensitivity of the ultrasonic transceiver.

[Assembly method of each member]
A method for assembling each member of the measuring tube 30 will be described with reference to FIGS. FIG. 6 is a partially transparent view of the measuring tube 30. FIG. 7 is a cross-sectional view of the measurement tube 30 in a state where the turbulent flow suppressing member 60 is assembled to the protruding member 90 in FIG.
First, the turbulent flow suppressing member 60 is fitted into the storage portion 45 provided on the inner wall surface of the first side wall portion 30l from the direction of the arrow in FIG. At this time, as shown in FIG. 7, the protruding member 90 provided at the upper position of the first sensor hole 41 is inserted into the mounting hole 62 of the turbulent flow suppressing member 60. Then, the turbulence suppressing member 60 is also fitted into the storage portion 45 provided on the inner wall surface of the second side wall portion 30r. Also in this case, the protruding member 90 provided at the lower position of the second sensor hole 52 is inserted into the mounting hole 62 of the turbulent flow suppressing member 60.
Further, one edge of the rectifying plate 70 is fitted into the groove portion 85 provided on the inner wall surface of the first side wall portion 301 from the arrow direction in FIG.

Next, the second measurement tube member 50 is moved closer to the first measurement tube member 40 from the direction of the arrow in FIG.
The edge of the long side of the upper surface part 30u abuts on the first side wall part 30l. At the same time, the edge of the long side of the lower surface portion 30d abuts below the second side wall portion 30r.
Then, the protruding member 90 provided above the first side wall portion 30l is inserted into the insertion hole 80 provided in the upper surface portion 30u. At this time, the protruding member 90 provided at the upper position of the first sensor hole 41 is also inserted into the corresponding insertion hole 80. The protrusion member 90 is inserted into the insertion hole 80 in a state of being inserted into the attachment hole 62 of the turbulent flow suppressing member 60. And the fixing | fixed part 61 of the turbulent flow suppression member 60 will be in the state pressed and fixed by the upper surface part 30u to the 1st side wall part 30a.

  At the same time, the protruding member 90 provided below the second side wall portion 30r is also inserted into the insertion hole 80 provided in the lower surface portion 30d. At this time, the protruding member 90 provided at the lower position of the second sensor hole 52 is also inserted into the corresponding insertion hole 80. The protrusion member 90 is inserted into the insertion hole 80 in a state where the protrusion member 90 is inserted into the attachment hole 62 of the turbulent flow suppression member 60. And the fixing | fixed part 61 of the turbulent flow suppression member 60 will be in the state pressed and fixed by the lower surface part 30d to the 2nd side wall part 30b.

The other edge of the current plate 70 is fitted into a groove 85 provided on the inner wall surface of the second side wall 30r. Thereby, the rectifying plate 70 is bridged between the first side wall part 30l and the second side wall part 30r. As shown in FIG. 6, the rectifying plate 70 is disposed across the turbulent flow suppressing member 60. In this state, one edge of the rectifying plate 70 presses the turbulent flow suppressing member 60 arranged on the first side wall portion 30l from the inside of the measuring tube 30 to the first side wall portion 30l. At the same time, the other edge of the rectifying plate 70 presses the turbulent flow suppressing member 60 disposed on the second side wall 30r from the inside of the measuring tube 30 to the second side wall 30r.
In this manner, the turbulent flow suppressing member 60 is assembled at the same time as the measurement tube 30 is assembled. In the above assembling operation, a predetermined jig is used as necessary.

[Action / Effect]
First, according to the gas meter 1, the turbulent flow suppressing member 60 is assembled to the sensor holes 41 and 52 simultaneously with the assembling work of the measuring tube members 40 and 50. Therefore, the assembling time in the assembling work of the measuring pipe 30 can be shortened as compared with the case where the assembling work of the measuring pipe members 40 and 50 and the assembling work of the turbulent flow suppressing member 60 are performed separately. . As a result, it is possible to save time and labor when assembling the gas meter 1.
In the preparatory stage for assembly, the protruding member 90 is inserted into the mounting hole 62 with the turbulent flow suppressing member 60 fitted in the storage portion 45. For this reason, positioning of the turbulent flow suppressing member 60 can be performed simultaneously. That is, the protruding member 90 that is an assembling means of the measuring tube 30 also serves as a positioning means for the turbulent flow suppressing member 60.

Next, the turbulent flow suppressing member 60 is pressed against the side wall portions 30l and 30r from the inside of the measuring tube 30 using the rectifying plate 70, thereby preventing the turbulent flow suppressing member 60 from being displaced inward of the measuring tube 30 or To reduce. That is, the appropriate position state of the current plate 70 can be maintained.
Next, the surface of the turbulent flow suppressing member 60 facing the inside of the measurement tube 30 and the inner wall surfaces of the side wall portions 30l and 30r in which the sensor holes 41 and 52 are formed are substantially on the same plane. For this reason, gas flows smoothly compared with the case where there exists a level | step difference between the said surface of the turbulent flow suppression member 60, and each side wall part 30l, 30r inner wall surface. That is, the occurrence of turbulent flow due to the collision of gas with the step is prevented or reduced.

[Other embodiments]
The gas meter 1 according to the present invention is not limited to the above-described embodiment, and can take other various embodiments.
First, the shape and size of each of the sensor holes 41 and 52 are appropriately changed according to the shape and size of the ultrasonic transceiver to be attached. At this time, the shape of the ultrasonic wave passage portion 63 of the turbulent flow suppressing member 60 is also formed corresponding to the shape and size of each sensor hole 41, 52.
Further, the number of the groove portions 85 is appropriately changed according to the number of the rectifying plates 70 arranged.

Next, as long as the sensor holes 41 and 52 can be covered, the shape of the turbulent flow suppression member 60 can take various shapes such as a circle and a polygon. At this time, the shape of the storage portion 45 is also appropriately changed according to the shape of the turbulent flow suppression member 60.
The shape of the fixed portion 61 of the turbulent flow suppressing member 60 can also be changed as appropriate.
Next, the shape of the protruding member 90 may be a prism such as a triangular prism, a quadrangular prism, or a hexagonal prism.
Further, the number and arrangement interval of the protruding members 90 can be changed as appropriate. There may be a plurality of protruding members 90 provided above the sensor holes 41 and 52. In this case, a plurality of holes of the fixing part 61 are also formed.

It is an external view of a gas meter. It is an internal structure figure of a gas meter. It is an exploded view of a gas flow measurement channel. It is an exploded view of a measuring tube. It is a front view of a turbulent flow suppression board. It is a partially transparent figure of a measuring tube. It is sectional drawing of a 1st measurement pipe member and a turbulent flow suppression board.

DESCRIPTION OF SYMBOLS 1 Gas meter 3 Gas supply source inlet 5 Gas equipment outlet 7 Display means 9 Terminal cover 10 Gas flow path 10a Shut-off valve 15 Gas flow path 15a Pressure sensor 20 Gas flow measurement flow path 21 Main body case 21a Top cover member 21b Bottom cover member 22 , 23 Opening 30 Measurement tube 30l First side wall 30r Second side wall 30u Top surface 30d Bottom surface 40 Measurement tube member 41 First sensor hole 45 Storage portion 50 Second measurement tube member 52 Second sensor Hole 60 Turbulence suppressing member 61 Fixed part 62 Mounting hole 63 Ultrasonic passage part 70 Current plate 72 Projection part 80 Insertion hole 85 Groove part 90 Projection member

Claims (3)

A gas meter that measures the flow rate of gas flowing through a measurement channel using ultrasonic waves,
The measurement channel is a cylinder having a quadrangular cross section, a first measurement channel member having a substantially L-shaped cross section that forms two adjacent sides of the measurement channel, and the other two adjacent measurement channels. Formed with a second measurement flow path member having a substantially L-shaped cross section forming a side,
A propagation window for allowing ultrasonic waves to pass through is formed on the opposing surfaces of the first measurement channel member and the second measurement channel member, and the measurement channel is disposed in the propagation window. A turbulent flow suppressing member that prevents the outflow of gas from the propagation window portion to the outside by covering the propagation window portion from the inner side is attached,
The turbulent flow suppressing member is formed with a fixed portion that is disposed at a position corresponding to a contact portion between the first measurement channel member and the second measurement channel member,
Assembling means for assembling both of the first measurement flow path member and the second measurement flow path member is formed on the contact portion of the first measurement flow path member, and the fixed portion of the turbulent flow suppression member is assembled. utilizing means have a structure for fixing the abutment portion,
The assembling means includes a convex portion provided at one contact location part of the first measurement flow path member and the second measurement flow path member, and the protrusion provided at the other contact location part. It consists of a recess that can be inserted into
The gas meter according to claim 1, wherein a hole portion through which a convex portion provided at the one contact portion portion can be inserted is formed in the fixed portion of the turbulent flow suppressing member . The gas meter according to claim 1,
The measurement flow path includes a rectifying plate that regulates the flow of gas,
The rectifying plate is disposed at a position where the turbulent flow suppressing member is pressed against the measurement channel from the inside of the measurement channel . The gas meter according to claim 1 or 2,
The turbulent flow suppressing member can be fitted, and a surface of the turbulent flow suppressing member that faces the measurement flow channel inner side in a fixed state and a surface of the measurement flow channel inner side on which the propagation window portion is formed. A gas meter, wherein concave portions having substantially the same plane are formed in the first measurement channel member and the second measurement channel member .

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