Ultrasonic vortex flowmeter and method for manufacturing the ultrasonic vortex flowmeter

Abstract

To provide a technique capable of suppressing man-hours in a manufacturing process of an ultrasonic vortex flowmeter.SOLUTION: An ultrasonic vortex flowmeter 1 includes: a measuring tube 11 having a vortex generator 110 for generating a Karman vortex in flowing fluid in a flow path; a pair of ultrasonic sensors 14, 15 that is fixed to the measuring tube 11 across the flow path of the measuring tube 11 and detects a Karman vortex; a board 20 electrically connected to the pair of ultrasonic sensors 14. 15; and a case 40 for housing a measurement part including mounting parts 12, 13 for fixing the pair of ultrasonic sensors 14, 15 in the measuring tube 11, and the board 20, in different sections by a partition wall part. The case 40 includes mutually divided case members 41 and case members 42, a partition wall part 411 corresponding to one portion of the partition wall part is provided in the case member 41, and a partition wall 421 corresponding to the remaining part of the partition wall parts is provided in the case member 42.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to ultrasonic vortex flow meters and the like. [Background technology]

[0002] Conventionally, an ultrasonic vortex flowmeter has been known in which a pair of ultrasonic sensors are arranged opposite each other across a measuring tube having a component that generates Karman vortices in the flow path, and the flow rate of a fluid passing through the measuring tube is measured by detecting Karman vortices in the flow path (see Patent Document 1).

[0003] In Patent Document 1, the case (housing) of the ultrasonic vortex flowmeter is composed of an amplifier case that houses a circuit board, a bottom plate that closes the bottom of the amplifier case, and a main body case that holds a measuring tube so as to house an ultrasonic sensor and is assembled to the amplifier case. This allows the bottom plate of the amplifier case to separate the space inside the case into one that houses the circuit board and one that holds and houses the measuring tube. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-164371 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, the manufacturing process requires two steps: a step of assembling a bottom plate to an amplifier case that houses a circuit board, and a step of assembling a main body case that holds a measuring tube to an amplifier case that is integrated with the bottom plate. Therefore, the number of steps in the manufacturing process may become relatively large.

[0006] In view of the above problems, an object of the present invention is to provide a technique that can reduce the number of steps in the manufacturing process of an ultrasonic vortex flowmeter. [Means for solving the problem]

[0007] In order to achieve the above object, in one embodiment of the present disclosure, a measuring tube having a flow path including a member for generating Karman vortices in a fluid flowing therethrough; a pair of ultrasonic sensors fixed to the measuring pipe so as to face each other across the flow path of the measuring pipe and detecting the Karman vortex; a substrate electrically connected to the pair of ultrasonic sensors; a housing that houses a measuring unit including a portion of the measuring pipe to which the pair of ultrasonic sensors are fixed and the substrate in different compartments by a partition wall, the housing includes a first housing portion and a second housing portion that are separated from each other; a first partition wall portion corresponding to a part of the partition wall portion is provided in the first housing portion, and a second partition wall portion corresponding to the remaining part of the partition wall portion is provided in the second housing portion; An ultrasonic vortex flow meter is provided.

[0008] In another embodiment of the present disclosure, a first step of attaching the substrate to the inside of the first housing part or the second housing part; a second step of attaching the measuring pipe including the pair of ultrasonic sensors to the inside of the first housing portion or the second housing portion; and a third step of assembling the first housing part and the second housing part. A method for manufacturing the above ultrasonic vortex flowmeter is provided. [Effects of the Invention]

[0009] According to the above-described embodiment, the number of steps in the manufacturing process of the ultrasonic vortex flowmeter can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an exploded perspective view showing an example of an ultrasonic vortex flowmeter. [Figure 2]FIG. 1 is an external view illustrating an example of an ultrasonic vortex flowmeter. [Figure 3] FIG. 1 is a cross-sectional view showing an example of an ultrasonic vortex flowmeter. [Figure 4] FIG. 1 is a cross-sectional view showing an example of an ultrasonic vortex flowmeter. [Figure 5] FIG. 1 is a cross-sectional view showing an example of an ultrasonic vortex flowmeter. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment will be described with reference to the drawings.

[0012] [Structure of ultrasonic vortex flowmeter] The structure of an ultrasonic vortex flowmeter 1 according to this embodiment will be described with reference to FIGS.

[0013] Fig. 1 is an exploded perspective view showing an example of an ultrasonic vortex flowmeter 1. Fig. 2 is an external view showing an example of the ultrasonic vortex flowmeter 1. Specifically, Fig. 2 is a side view of the ultrasonic vortex flowmeter 1 as viewed from the negative Y-axis direction along the Y-axis. Figs. 3 to 5 are cross-sectional views showing an example of the ultrasonic vortex flowmeter 1. Specifically, Fig. 3 is a cross-sectional view of the ultrasonic vortex flowmeter 1 at the center in the Y-axis direction, taken along a plane parallel to the X-axis and Z-axis, and Figs. 4 and 5 are cross-sectional views taken along lines AA and BB in Fig. 2, respectively.

[0014] Hereinafter, explanations may be made using an orthogonal coordinate system defined by the X-axis, Y-axis, and Z-axis shown in Figures 1 to 5. The positive X-axis direction (+X) and the negative X-axis direction (-X) may be collectively referred to as the X-axis direction. Similarly, the positive Y-axis direction (+Y) and the negative Y-axis direction (-Y) may be collectively referred to as the Y-axis direction. Similarly, the positive Z-axis direction (+Z) and the negative Z-axis direction (-Z) may be collectively referred to as the Z-axis direction.

[0015] As shown in FIGS. 1 to 5, the ultrasonic vortex flowmeter 1 includes a main body 10, a substrate 20, a communication line 30, a case 40, a packing 50, a grommet 60, O-rings 70 and 80, and a screw 90.

[0016] The ultrasonic vortex flowmeter 1 generates Karman vortices in the fluid flowing through the flow path of the measuring tube 11 using a vortex generator 110 arranged in the flow path (pipe line) of the measuring tube 11, and measures the flow rate of the fluid by detecting the Karman vortices in the flow path with a pair of ultrasonic sensors 14, 15.

[0017] The main body 10 includes a measuring pipe 11, mounting portions 12 and 13, and ultrasonic sensors 14 and 15.

[0018] The measuring pipe 11 is a pipe through which a fluid whose flow rate is to be measured flows. The measuring pipe 11 has a substantially circular cross section of the flow path and is provided so as to extend along the X-axis. Specifically, the measuring pipe 11 includes a measuring pipe 11A in the center in the X-axis direction, an inlet pipe 11B connected to the measuring pipe 11A in the negative X-axis direction and allowing the fluid to flow into the measuring pipe 11A, and an outlet pipe 11C connected to the measuring pipe 11A in the positive X-axis direction and allowing the fluid to flow out of the measuring pipe 11A. The measuring pipe 11A is accommodated in a case 40. Hereinafter, the measuring pipe 11A, the mounting units 12 and 13 provided on the measuring pipe, and the ultrasonic sensors 14 and 15 may be referred to as a "measuring unit" for convenience.

[0019] As shown in FIG. 3, a columnar vortex generator 110 is provided in the flow path of the measuring pipe 11A.

[0020] The vortex generator 110 is disposed upstream of the positions in the X-axis direction where the ultrasonic sensors 14 and 15 are provided, that is, on the negative X-axis direction side.

[0021] Furthermore, the measuring pipe 11A is provided with bosses 111 to 114 for fixing the measuring pipe 11 to the case 40.

[0022] Boss 111 is provided so as to protrude in the positive direction of the Z axis from the circular top portion in the positive direction of the Z axis at a location closer to the positive direction of the X axis from the center in the X axis direction of measuring pipe 11A where ultrasonic sensors 14, 15 are provided. The width of boss 111 in the Y axis direction is approximately the same as that of bosses 113, 114. The term "approximately" is intended to allow for, for example, manufacturing errors, and will be used in the same sense hereinafter. Boss 111 fits into groove 414 of case 40 (case member 41).

[0023] Boss 112 is provided so as to protrude in the negative Z-axis direction from the circular top portion in the negative Z-axis direction at a location closer to the positive X-axis direction from the center in the X-axis direction where ultrasonic sensors 14 and 15 of measuring pipe 11A are provided. The width of boss 112 in the Y-axis direction is set larger than that of bosses 111, 113, and 114. Boss 112 fits into groove 415 of case 40 (case member 41).

[0024] Boss 113 is provided so as to protrude in the positive Z-axis direction from the circular top portion in the positive Z-axis direction at a location closer to the negative X-axis direction from the center in the X-axis direction where ultrasonic sensors 14 and 15 of measuring pipe 11A are provided. The width of boss 113 in the Y-axis direction is approximately the same as that of bosses 111 and 114. Boss 113 fits into groove 424 of case 40 (case member 42).

[0025] Boss 114 is provided so as to protrude in the negative Z-axis direction from the circular top portion in the negative Z-axis direction at a location closer to the negative X-axis direction from the center in the X-axis direction where ultrasonic sensors 14, 15 of measuring pipe 11A are provided. The width of boss 114 in the Y-axis direction is approximately the same as that of bosses 111, 113. Boss 114 fits into groove 425 of case 40 (case member 42).

[0026] Mounting portions 12 and 13 are provided on measuring pipe 11A and are used to mount ultrasonic sensors 14 and 15, respectively.

[0027] The mounting part 12 is provided at the center of the measurement pipe 11A in the X-axis direction, at the circular top in the positive Z-axis direction, and has a substantially rectangular parallelepiped shape with each side aligned with the X-axis, Y-axis, and Z-axis. The mounting part 12 has an opening in the positive Z-axis direction and an internal space in which the ultrasonic sensor 14 can be mounted.

[0028] The mounting part 13 is provided at the center of the measurement pipe 11A in the X-axis direction, at the circular top part in the negative Z-axis direction, and has a substantially rectangular parallelepiped shape with each side aligned with the X-axis, Y-axis, and Z-axis. The mounting part 13 has an opening in the negative Z-axis direction and an internal space capable of accommodating the ultrasonic sensor 15.

[0029] The ultrasonic sensor 14 is attached to the attachment portion 12. The ultrasonic sensor 14 includes a piezoelectric element 141, fixing members 142 and 143, and a cover member 144.

[0030] The piezoelectric element 141 is disposed at the innermost part of the internal space of the attachment portion 12 (the end in the negative Z-axis direction).

[0031] The fixing members 142 and 143 are disposed adjacent to the piezoelectric element 141 in the positive direction of the Z axis so as to fill the space between the piezoelectric element 141 and the lid member 144.

[0032] Lid member 144 is heat-welded to the end of mounting portion 12 in the positive Z-axis direction to close the opening at that end. In addition, the surface of lid member 144 in the positive Z-axis direction is configured to have a predetermined gap with a predetermined portion provided inside case member 41.

[0033] The ultrasonic sensor 15 is attached to the attachment portion 13. The ultrasonic sensor 15 includes a piezoelectric element 151, fixing members 152 and 153, and a cover member 154.

[0034] The piezoelectric element 151 is disposed at the innermost part of the internal space of the attachment portion 13 (the end in the positive direction of the Z axis).

[0035] The fixing members 152 and 153 are disposed adjacent to the piezoelectric element 151 in the negative Z-axis direction so as to fill the space between the piezoelectric element 151 and the lid member 154.

[0036] Lid member 154 is heat-welded to the end of mounting portion 13 in the negative Z-axis direction to close the opening at that end. In addition, the surface of lid member 154 in the negative Z-axis direction is configured to have a predetermined gap with a predetermined portion provided inside case member 41.

[0037] The measuring section of the main body 10 (the measuring pipe 11A, the mounting sections 12 and 13 provided on the measuring pipe 11A, and the ultrasonic sensors 14 and 15) is housed in a space SP1 inside the case 40.

[0038] The board 20 is electrically connected to the ultrasonic sensors 14, 15 via predetermined conductors, and performs various processes based on signals output from one of the ultrasonic sensors 14, 15 and received by the other ultrasonic sensor. The various processes include measuring (calculating) the flow rate of the fluid flowing through the measuring pipe 11 based on the signals from the ultrasonic sensors 14, 15. Specifically, the ultrasonic waves output from one of the ultrasonic sensors 14, 15 are modulated by Kármán vortices generated downstream of the vortex shedder 110 by the flow of the fluid to be measured, and then received by the other ultrasonic sensor. The board 20 uses this signal to calculate the measured flow rate of the fluid to be measured. The board 20 transmits the results of the processes to the outside via the communication line 30.

[0039] The substrate 20 has a generally rectangular parallelepiped shape of a flat plate with sides aligned along the X-axis, Y-axis, and Z-axis, and is disposed in a space SP2 separated from the space SP1 inside the case 40.

[0040] The communication line 30 is used for communication between the board 20 and an external device, thereby making it possible to output the results of processing on the board 20 to the external device.

[0041] The communication line 30 is provided so as to extend from the space SP2 of the case 40 in the negative direction of the X axis.

[0042] The case 40 (an example of a housing) is used to secure the components of the ultrasonic vortex flowmeter 1, such as the main body 10, the substrate 20, and the communication line 30. The case 40 accommodates the measurement unit of the main body 10, the substrate 20, and the base end of the communication line 30, and holds the main body 10 in a manner that exposes the inlet pipe 11B, the outlet pipe 11C, and the base end of the communication line 30 to the outside.

[0043] The case 40 includes case members 41 and 42 that are combined to face each other in the X-axis direction. The case members 41 and 42 are, for example, resin molded products.

[0044] Case member 41 (an example of a first housing unit) is disposed opposite case member 42 in the positive X-axis direction. Case member 41 has a generally rectangular parallelepiped shape with sides aligned along the X-axis, Y-axis, and Z-axis, and has an opening in the negative X-axis direction where case member 42 is disposed.

[0045] The case member 41 includes a partition wall portion 411 , a through hole 412 , a groove portion 413 , groove portions 414 and 415 , and seat portions 416 , 417 and 418 .

[0046] Partition wall 411 (an example of a first partition wall) is provided in the center of case member 41 in the Z-axis direction so as to extend substantially parallel to the X-axis and Y-axis, and divides the internal space of case member 41 into a space in the positive Z-axis direction and a space in the negative Z-axis direction. This divides the opening of case member 41 into an opening in the positive Z-axis direction and an opening in the negative Z-axis direction. The end of partition wall 411 in the negative X-axis direction is located at substantially the same position as the end of case member 41 in the X-axis direction.

[0047] The through-hole 412 is provided on the end face of the case member 41 in the positive X-axis direction at a position further in the negative Z-axis direction than the partition wall portion 411, and penetrates in the X-axis direction between the inside and outside of the case member 41. The measuring tube 11 is inserted into the through-hole 412 so that the outflow tube 11C protrudes outside the case member 41.

[0048] Groove 413 (an example of a first groove) is provided on the inner surface of case member 41 closer to the positive X-axis direction than partition wall 411 in the positive Z-axis direction. Groove 413 includes a pair of grooves 413a and 413b provided on the inner surface facing the positive Y-axis direction and the negative Y-axis direction, respectively, to extend in the X-axis direction. Groove 413 has a width in the Z-axis direction that is the same as or slightly larger than the thickness of substrate 20, and the distance in the Y-axis direction between the bottoms of grooves 413a and 413b in the positive Y-axis direction and the negative Y-axis direction is set to be approximately the same as or slightly larger than the dimension of substrate 20 in the Y-axis direction. This allows groove 413 to hold substrate 20 when substrate 20 is inserted.

[0049] 3, the grooves 413 are provided at two different positions in the Z-axis direction. Specifically, as shown in FIG. 5, one groove 413 is located at a first position in the Z-axis direction inside the case member 41 and includes a pair of grooves 413a, 413b that are located at the same position in the Z-axis direction inside the case member 41 and are formed in both the positive and negative Y-axis directions inside the case member 41. Similarly, the other groove 413 includes another pair of grooves 413a, 413b that are located at a second position different from the first position in the Z-axis direction. As a result, for example, when two boards 20 are to be mounted, one board 20 can be mounted in each of the two pairs of grooves 413a, 413b. Furthermore, appropriate grooves 413 can be selected from the two grooves 413 located at different positions in the Z-axis direction depending on the constraints of the manufacturing lines that manufacture the same product (ultrasonic vortex flowmeter 1) and the boards 20 with different specifications.

[0050] Note that, when the number of substrates 20 to be mounted is one, only one groove 413 (groove portions 413a, 413b) may be provided, or when the number of substrates 20 to be mounted is three or more, groove portions 413 may be provided at different positions in the Z-axis direction in numbers equal to or greater than the number of substrates 20. The same may be true for groove portion 423 described below.

[0051] Groove portion 414 is provided in the circular top portion in the positive Z-axis direction of the inner circumferential surface of through-hole 412, recessed in the positive Z-axis direction and extending in the X-axis direction. Groove portion 414 accommodates boss 111 of measuring pipe 11A. The width (dimension in the Y-axis direction) of groove portion 414 is approximately the same as groove portions 424 and 425, which will be described later.

[0052] Groove 415 is provided at the circular top portion of the inner circumferential surface of through hole 412 in the negative Z-axis direction, recessed in the negative Z-axis direction, and extending in the X-axis direction. Groove 415 accommodates boss 112 of measurement pipe 11A. The width (dimension in the Y-axis direction) of groove 415 is larger than groove 414 and grooves 424 and 425 described below, to match the width of boss 112, which is larger than the width of bosses 111, 113, and 114. This allows the worker to check the difference in width between boss 112 and bosses 111, 113, and 114 of measurement pipe 11A and the difference in width between groove 415 and grooves 414, 424, and 425 of case 40, thereby enabling accurate assembly work and preventing incorrect assembly.

[0053] The bearing surface portions 416 to 418 are provided for bearing the screws 90 .

[0054] Seat portion 416 has a flat plate shape that protrudes in the Z-axis positive direction from the end of the Z-axis positive side of the end face of case member 41 in the X-axis positive direction, and is substantially parallel to the Y-axis and Z-axis. Through holes are provided at both ends of seat portion 416 in the Y-axis positive direction and the Y-axis negative direction, allowing screws 90 to be inserted substantially along the X-axis direction.

[0055] The seating surface portions 417 are provided at the corners of the case member 41 facing the positive Y-axis direction and the negative Y-axis direction at the end facing the negative X-axis direction and the end facing the negative Z-axis direction, and have a flat plate shape substantially parallel to the Y-axis and Z-axis. The seating surface portions 417 are provided with through holes that allow the screws 90 to be inserted substantially along the X-axis direction. Corners of the case member 41 facing the negative Z-axis direction and the positive Y-axis direction and corners facing the negative Z-axis direction and the negative Y-axis direction are recessed inwardly, as if cut out, on the sides of the seating surface portion 417 in the positive X-axis direction. This allows the seating surface portion 417 to be exposed when the case member 41 is viewed from the positive X-axis direction, allowing the screws 90 to be inserted through the through holes in the seating surface portion 417.

[0056] The seating surface portion 418 is provided at both ends in the positive and negative Y-axis directions at approximately the same position in the Z-axis direction as the partition wall portion 411 of the case member 41 and at the end in the X-axis direction, and has a flat plate shape approximately parallel to the Y-axis and Z-axis. The seating surface portion 418 is provided with a through-hole through which the screw 90 can be inserted approximately along the X-axis direction. The both end faces in the positive and negative Y-axis directions at approximately the same position in the Z-axis direction as the partition wall portion 411 of the case member 41 are recessed inward beyond the seating surface portion 418 in the positive X-axis direction. This allows the seating surface portion 418 to be exposed when the case member 41 is viewed from the positive X-axis direction, allowing the screw 90 to be inserted through the through-hole in the seating surface portion 418.

[0057] Case member 42 (an example of a second housing unit) is disposed opposite case member 41 in the negative X-axis direction. Case member 42 has a generally rectangular parallelepiped shape with sides aligned with the X-axis, Y-axis, and Z-axis, and has an opening in the positive X-axis direction where case member 41 is disposed.

[0058] The case member 42 includes a partition wall portion 421 , a through-hole 422 , a groove portion 423 , groove portions 424 and 425 , a protrusion portion 426 , and a screw hole 427 .

[0059] Partition wall 421 (an example of a second partition wall) is provided in the center of case member 42 in the Z-axis direction so as to extend substantially parallel to the X-axis and Y-axis, and divides the internal space of case member 42 into a space in the positive Z-axis direction and a space in the negative Z-axis direction. The position of partition wall 421 in the Z-axis direction is substantially the same as that of partition wall 411 of case member 41. This allows partition wall portions 411, 421 to divide the internal space of case 40 into a space SP2 in the positive Z-axis direction and a space SP1 in the negative Z-axis direction.

[0060] The end of partition wall 421 in the positive X-axis direction is recessed in the negative X-axis direction at a part in the Y-axis direction, for example, at the center in the Y-axis direction, and a gap is provided at this location between partition wall 421 and partition wall 411 (specifically, packing 50 abutting partition wall 411). This allows a conducting wire for electrically connecting ultrasonic sensors 14, 15 and substrate 20 to pass through this gap (recess).

[0061] The through hole 422 is provided on the end face of the case member 42 in the negative X-axis direction at a position in the negative Z-axis direction relative to the partition wall portion 421, and passes through in the X-axis direction between the inside and outside of the case member 42. The measuring pipe 11 is inserted into the through hole 422 so that the inflow pipe 11B protrudes to the outside of the case member 42.

[0062] Groove 423 (an example of a second groove) is provided on the inner surface of case member 42 closer to the positive X-axis direction at a position in the positive Z-axis direction than partition wall 421. Groove 423 is provided at approximately the same position in the Z-axis direction as groove 413 so as to face groove 413 in the X-axis direction. Groove 423 includes a pair of grooves 423a and 423b provided on the inner surface facing the positive Y-axis direction and the negative Y-axis direction so as to extend in the X-axis direction. The width of groove 423 in the Z-axis direction is the same as or slightly larger than the thickness of substrate 20, and the distance in the Y-axis direction between the bottoms of grooves 423a and 423b in the positive Y-axis direction and the negative Y-axis direction is set to be approximately the same as or slightly larger than the dimension of substrate 20 in the Y-axis direction. This allows groove 423 to hold substrate 20 when substrate 20 is inserted.

[0063] Groove portion 424 is provided in the circular top portion in the positive Z-axis direction of the inner circumferential surface of through-hole 422, so as to be recessed in the positive Z-axis direction and extend in the X-axis direction. Groove portion 424 receives boss 113 of measuring pipe 11A. The width (dimension in the Y-axis direction) of groove portion 424 is approximately the same as groove portions 414 and 425.

[0064] Groove portion 425 is provided in the circular top portion of the inner circumferential surface of through-hole 422 in the negative Z-axis direction, recessed in the negative Z-axis direction and extending in the X-axis direction. Groove portion 425 accommodates boss 114 of measuring pipe 11A. The width (dimension in the Y-axis direction) of groove portion 425 is approximately the same as groove portions 414 and 424.

[0065] The protrusions 426 are provided on the inner surfaces of the case member 42 in the positive and negative Y-axis directions, starting from the end of the case member 42 in the positive X-axis direction and extending in the negative X-axis direction. This prevents the packing 50 from sinking into the internal space of the case member 42, even if a force that slightly displaces the packing 50 in the Y-axis direction is applied to the packing 50 during the manufacturing process of the ultrasonic vortex flowmeter 1. This allows the packing 50 to more appropriately perform its function. For example, as shown in FIG. 4 , the protrusions 426 are provided at four different positions in the Z-axis direction on the inner surface of the case member 42 in the positive Y-axis direction. Specifically, the protrusions 426 may be arranged at two different positions in the Z-axis direction closer to the positive Z-axis direction than the partition wall 421 and two different positions in the Z-axis direction closer to the negative Z-axis direction than the partition wall 421 on the inner surface of the case member 42 in the positive Y-axis direction. Similarly, for example, protrusions 426 are provided at four different positions in the Z axis direction on the inner surface of case member 42 facing the negative Y axis. Specifically, protrusions 426 may be arranged on the inner surface of case member 42 facing the negative Y axis at two different positions in the Z axis direction closer to the positive Z axis direction than partition wall 421, and at two different positions in the Z axis direction closer to the negative Z axis direction than partition wall 421. Furthermore, protrusions 426 on the inner surface facing the positive Y axis direction and protrusions 426 on the inner surface facing the negative Y axis direction may be aligned in the Z axis direction so as to be at the same position in the Z axis direction.

[0066] Threaded hole 427 is provided so as to extend in the X-axis direction from the end face of case member 42 facing the X-axis positive direction, and has a female thread formed on the inner surface. Threaded hole 427 is provided at positions corresponding to the six through holes of seating surface portions 416 to 418 of case member 41, respectively.

[0067] The packing 50 is disposed so as to be sandwiched between the end of the case member 41 facing the negative X-axis direction and the end of the case member 42 facing the positive X-axis direction. The packing 50 is an elastic member made of a rubber material, a resin material, or the like, with a relatively high Young's modulus. This improves the waterproof performance of the case 40. The packing 50 abuts on the end faces of the outer wall facing the negative X-axis direction, which correspond to the end faces of the case member 41 facing the positive Z-axis direction, the negative Z-axis direction, the positive Y-axis direction, and the negative Y-axis direction, the end faces of the seating portions 416 to 418 facing the negative X-axis direction, and the entire end face of the partition wall portion 411 facing the negative X-axis direction. The packing 50 also abuts on the end faces of the outer wall facing the positive X-axis direction, which correspond to the end faces of the case member 42 facing the positive Z-axis direction, the negative Z-axis direction, the positive Y-axis direction, and the negative Y-axis direction, and the end face of the partition wall portion 421 facing the positive X-axis direction, excluding the recess for passing the conductor therethrough.

[0068] The grommet 60 (an example of an elastic member) is disposed in a gap in the X-axis direction between the packing 50 in contact with the case member 41 (partition wall portion 411) and a portion of the partition wall portion 421 of the case member 42 that is recessed in the negative X-axis direction. The grommet 60 is an elastic member made of a rubber material, a resin material, or the like with a relatively large Young's modulus. The grommet 60 is relatively larger than the gap between the packing 50 in contact with the partition wall portion 411 and the partition wall portion 421, and elastically deforms so as to be crushed between the packing 50 in contact with the case member 41 (partition wall portion 411) and the partition wall portion 421 of the case member 42. The grommet 60 is also provided with a groove or a through-hole that penetrates in the X-axis direction. As a result, grommet 60 can seal the gap in the X-axis direction between partition wall 421 and packing 50 abutting partition wall 411, while holding the conducting wires between ultrasonic sensors 14, 15 (piezoelectric elements 141, 151) and substrate 20 in the grooves or through-holes. Therefore, it is possible to partition space SP1 in which a measurement unit including measuring tube 11A is disposed and space SP2 in which substrate 20 is disposed with relatively high airtightness. Therefore, even when a high-temperature fluid flows through the flow path of measuring tube 11A, for example, it is possible to make it difficult for heat from the fluid to be transmitted to substrate 20, thereby preventing failure of substrate 20 due to overheating. Furthermore, it is possible to prevent a situation in which substrate 20 is damaged by the influence of condensation that may occur on the outer surface of measuring tube 11A due to temperature changes, for example.

[0069] The O-ring 70 is arranged so as to abut against the outer periphery of the measuring pipe 11A near the end in the positive direction of the X-axis and along the inner periphery of the through-hole 412. The O-ring 70 is made of a rubber material or a resin material with a relatively large Young's modulus. This can improve the waterproof performance of the case 40 at the through-hole 412 through which the measuring pipe 11 passes.

[0070] The O-ring 80 is arranged so as to abut against the outer periphery of the measurement pipe 11A near the end in the negative X-axis direction, and along the inner periphery of the through-hole 422. The O-ring 80 is made of a rubber material or a resin material with a relatively large Young's modulus. This can improve the waterproof performance of the case 40 at the through-hole 422 through which the measurement pipe 11 passes.

[0071] There are six screws 90, which are inserted into the six through holes of the seating surface portions 416 to 418 of the case member 41, respectively, and screwed into the screw holes 427 at corresponding positions of the case member 42. In this way, the screws 90 can fix the case members 41 and 42 together.

[0072] [How to assemble an ultrasonic vortex flowmeter] Next, one example of a method for assembling the ultrasonic vortex flowmeter 1 will be described with reference to FIGS.

[0073] For example, the ultrasonic vortex flowmeter 1 can be assembled by the following steps (1) to (6).

[0074] (1) The substrate 20 is inserted into the groove of either the case member 41 or the case member 42 (either the groove 413 or the groove 423) and held therein.

[0075] (2) The measuring pipe 11 is inserted into the through-holes 412, 422 of either the case member 41 or the case member 42, and the boss of the measuring pipe 11A is aligned with the groove of the case member, thereby positioning and holding the pipe. In the case of the case member 41, the measuring pipe 11 is inserted into the through-hole 412 of the case member 41, and the bosses 111, 112 of the measuring pipe 11A are aligned with the grooves 414, 415 of the case member 41, thereby positioning and holding the pipe. Similarly, in the case of the case member 42, the measuring pipe 11 is inserted into the through-hole 422 of the case member 42, and the bosses 113, 114 of the measuring pipe 11A are aligned with the grooves 424, 425 of the case member 42, thereby positioning and holding the pipe. In addition, the O-ring 70 provided on the measuring pipe 11A is disposed so as to abut against the outer periphery of the measuring pipe 11A near the end in the positive direction of the X-axis and along the inner periphery of the through-hole 412. Similarly, the O-ring 80 is disposed so as to abut against the outer periphery of the measuring pipe 11A near the end in the negative X-axis direction and along the inner periphery of the through-hole 422.

[0076] (3) Both ends of the conductor wire inserted into the through-hole or groove of the grommet 60 are connected to the substrate 20 and the ultrasonic sensors 14 and 15 (piezoelectric elements 141 and 151).

[0077] (4) A packing 50 is installed on the end surface of either the case member 41 or the case member 42.

[0078] (5) Insert the substrate 20 into the groove of either the case member 41 or the case member 42, and insert the measuring pipe 11 into the through holes 412, 422. While aligning the boss of the measuring pipe 11A with the groove of the case member, bring the case members 41, 42 into contact with each other via the packing 50. At this time, make sure that the grommet 60 is housed in the recess in the end face of the case member 42 in the positive direction of the X axis.

[0079] (6) Screws 60 are threaded through the through holes of the seating portions 416 to 418 into the screw holes 427 to fix the case members 41 and 42 together.

[0080] The above assembly order and contents are merely examples, and the order and contents may be changed as appropriate.

[0081] [Effect] Next, the operation of the ultrasonic vortex flowmeter 1 according to this embodiment will be described.

[0082] In this embodiment, the ultrasonic vortex flowmeter 1 includes a measuring tube 11, a pair of ultrasonic sensors 14 and 15, a substrate 20, and a case 40. Specifically, the measuring tube 11 has a vortex shedder 110 in its flow path that generates Karman vortices in the fluid flowing therethrough. The pair of ultrasonic sensors 14 and 15 are fixed to the measuring tube 11 so as to face each other across the flow path of the measuring tube 11, and detect Karman vortices. The substrate 20 is electrically connected to the pair of ultrasonic sensors 14 and 15. The case 40 houses the measuring unit, including the portions of the measuring tube 11 to which the pair of ultrasonic sensors 14 and 15 are fixed (mounting portions 12 and 13), and the substrate 20 in different compartments separated by a partition. The case 40 includes a case member 41 and a case member 42 that are separated from each other. A partition portion 411, which corresponds to a portion of the partition portion, is provided in the case member 41, and a partition portion 421, which corresponds to the remaining portion of the partition portion, is provided in the case member 42.

[0083] As a result, by simply assembling the two case members 41 and 42, it is possible to partition the space SP1 that houses the measuring tube 11 (measurement unit) and the space SP2 that houses the substrate 20. Therefore, compared to a case where three case members are required, for example, a case member that houses the measuring tube 11 (measurement unit), a case member that houses the substrate 20, and a case member that corresponds to the partition wall, it is possible to reduce the number of steps in the manufacturing process. Furthermore, since the number of parts can be reduced, it is possible to reduce costs.

[0084] In this embodiment, grooves 413 and 423 may be provided on the inner surfaces of case member 41 and case member 42, respectively. Substrate 20 may be fixed by grooves 413 and 423.

[0085] This allows the substrate 20 to be fixed in the groove of either one of the case members 41 and 42 when the case members 41 and 42 are combined, thereby improving workability in the manufacturing process.

[0086] In this embodiment, a gap may be provided between the partition wall portion 411 and the partition wall portion 421, in which a conducting wire is disposed to electrically connect the substrate 20 and the pair of ultrasonic sensors 14, 15. A grommet 60 may be disposed in the gap.

[0087] This allows the gap to be filled by elastic deformation of grommet 60. Therefore, the gap allows the conductive wires to be arranged to connect spaces SP1 and SP2, and grommet 60 can partition spaces SP1 and SP2 with higher airtightness.

[0088] In the present embodiment, the manufacturing method of the ultrasonic vortex flowmeter 1 may include first to third steps. Specifically, in the first step, the substrate 20 may be attached to the inside of the case member 41 or the case member 42. In the second step, the measuring tube 11 including the pair of ultrasonic sensors 14, 15 may be attached to the inside of the case member 41 or the case member 42. Then, in the third step, the case member 41 and the case member 42 may be assembled.

[0089] In this way, the ultrasonic vortex flowmeter 1 can be assembled.

[0090] Although the embodiments have been described in detail above, the present disclosure is not limited to such specific embodiments, and various modifications and variations are possible within the scope of the gist described in the claims. [Explanation of symbols]

[0091] 1 Ultrasonic vortex flowmeter 10 Main body 11 Measuring tube 11A measuring tube 11B Inflow pipe 11C Outflow pipe 12 Mounting part 13 Mounting part 14 Ultrasonic Sensor 15 Ultrasonic Sensor 20 Substrate 30 Communication lines 40 cases 41 Case material 42 Case material 50 packing 60 Grommets 70 O-rings 80 O-rings 110 Vortex generator 111 Boss 112 Boss 113 Boss 114 Boss 141 Piezoelectric element 142 Fixing member 143 Fixing member 144 Lid member 151 Piezoelectric element 152 Fixing member 153 Fixing member 154 Lid member 411 Bulkhead 412 Through hole 413 Groove 414 Groove 415 Groove 416 Seat part 417 Seat part 418 Seat part 421 Bulkhead 422 Through hole 423 Groove 424 Groove 425 Groove 426 Protrusion 427 screw hole SP1 Space SP2 space

Claims

1. a measuring tube having a flow path including a member for generating Karman vortices in a fluid flowing therethrough; a pair of ultrasonic sensors fixed to the measuring pipe so as to face each other across the flow path of the measuring pipe and detecting the Karman vortex; a substrate electrically connected to the pair of ultrasonic sensors; a housing that houses a measuring unit including a portion of the measuring pipe to which the pair of ultrasonic sensors are fixed and the substrate in different compartments by a partition wall, the housing includes a first housing portion and a second housing portion that are separated from each other; a first partition wall portion corresponding to a part of the partition wall portion is provided in the first housing portion, and a second partition wall portion corresponding to the remaining part of the partition wall portion is provided in the second housing portion; Ultrasonic vortex flow meter.

2. a first groove and a second groove are provided on inner surfaces of the first housing portion and the second housing portion, respectively; the substrate is fixed by the first groove and the second groove; 2. The ultrasonic vortex flowmeter of claim 1.

3. a gap is provided between the first partition wall and the second partition wall, through which a conducting wire is disposed to electrically connect the substrate and the pair of ultrasonic sensors; An elastic member is disposed in the gap.

3. The ultrasonic vortex flowmeter according to claim 1 or 2.

4. a first step of attaching the substrate to the inside of the first housing part or the second housing part; a second step of attaching the measuring pipe including the pair of ultrasonic sensors to the inside of the first housing portion or the second housing portion; a third step of assembling the first housing part and the second housing part together, A method for manufacturing the ultrasonic vortex flowmeter according to any one of claims 1 to 3.

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