Flowmeter

Abstract

To provide a flowmeter capable of reliably mounting a flow measurement unit whose mounting direction is prescribed in the prescribed direction.SOLUTION: A flowmeter includes: a flow measurement unit 10 which has a measurement channel section 11 through which a fluid to be measured flows and measures the flow rate of the fluid flowing through the measurement channel section 11; a gasket 30 which is attached to the downstream side of the flow of the fluid to be measured around the flow measurement unit 10 and is not attached to the upstream side of the flow of the fluid; and an internal machine case 50 which is attached from the outside with the flow measurement unit 10 on which the gasket 30 is attached, and which flows the fluid to be measured flowing through the measurement channel section 11 of the flow measurement unit 10 and relays the fluid to a discharge path which discharges the fluid.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present application relates to a flow meter that measures the flow rate of a fluid to be measured. [Background technology]

[0002] Patent Document 1 describes an ultrasonic flowmeter configured by incorporating a flow rate measurement unit into a housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-90361 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the ultrasonic flowmeter described in Patent Document 1, when assembling the flow measurement unit, if the assembling direction is specified, there is a risk that the upstream side and the downstream side will be assembled in the opposite direction.

[0005] An object of the present application is to provide a flowmeter that enables a flow measurement unit, whose installation direction is specified, to be installed in the specified direction without fail. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the flow meter of the present application is characterized in that it comprises a flow measurement unit having a measurement flow path section through which the measured fluid flows and which measures the flow rate of the measured fluid flowing through the measurement flow path section, a gasket which is attached around the flow measurement unit on the downstream side of the flow of the measured fluid and not on the upstream side of the flow of the measured fluid, and a relay case to which the flow measurement unit with the gasket attached is attached from the outside, which receives the measured fluid that has flowed through the measurement flow path section of the flow measurement unit and relays it to a discharge path that discharges the measured fluid.

[0007] In the flowmeter of the present application, the packing is attached to the downstream side of the flow of the fluid to be measured around the flow measurement unit, and not to the upstream side of the flow of the fluid to be measured, so that it is possible to prevent the packing from being attached erroneously around the flow measurement unit. And since the flow measurement unit with the packing attached is attached to the relay case from the outside, that is, a flow measurement unit without the packing attached cannot be attached to the relay case from the outside, it is possible to attach the flow measurement unit with a specified attachment direction in the specified direction without fail.

[0008] The flow measurement unit also has grooves formed on the downstream and upstream sides of its periphery, into which a gasket can be fitted, and a protrusion located between the upstream groove and the downstream groove and provided at a position where the distance to the upstream groove is narrower than the distance to the downstream groove, and the gasket has a rib of a predetermined length formed on the surface opposite to the surface that faces when attached to the relay case, and when the gasket is fitted into the upstream groove, the rib abuts against the protrusion, making it impossible for the gasket to be fitted into the upstream groove.

[0009] This allows an operator attaching the packing to the flow rate measuring unit to know if the packing is attached from the wrong direction, thereby preventing incorrect attachment.

[0010] The packing is also circular in plan view, the relay case has a circular hole for attaching the circular packing, and a plurality of boss portions formed around the hole, which determine the rotation angle of the packing relative to the hole when the packing is attached, and the packing has a plurality of flange portions formed on its circular periphery, and each of the plurality of flange portions has a hole formed at a position corresponding to each of the plurality of boss portions, which fits with each of the boss portions.

[0011] This allows an operator who attaches the flow measurement unit to the relay case via a gasket to simply attach the flow measurement unit to the relay case with each boss portion fitted into each hole in the multiple flanges, allowing the flow measurement unit to be attached to the relay case at an accurate angle in the rotational direction. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing the appearance of a state in which a flow rate measurement unit and an inner machine case included in a flow meter according to an embodiment of the present application are connected to each other; [Diagram 2] FIG. 4 is a perspective view showing a state before the flow rate measurement unit and the inner unit case are connected to each other. [Diagram 3] 1A is a cross-sectional perspective view showing a state in which a packing is correctly attached to a flow rate measurement unit, and FIG. 1B is an enlarged perspective view of region A. [Figure 4] 1A is a cross-sectional perspective view showing a state in which a gasket has been incorrectly attached to a flow rate measurement unit, and FIG. 1B is an enlarged perspective view of region B. [Diagram 5] 1A is a perspective view showing the state in which the flow rate measurement unit is correctly attached to the inner unit case, and FIG. 1B is an enlarged perspective view of area C. [Figure 6] 1A is a perspective view showing a state in which a flow rate measurement unit has been incorrectly attached to an inner unit case, and FIG. 1B is an enlarged perspective view of area C. [Figure 7] 13 is a perspective view showing the external appearance of a state in which a flow rate measurement unit and an inner machine case included in a flow meter according to another embodiment of the present application are connected to each other. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments of the present application will be described in detail with reference to the drawings. In the drawings used in the following description, some basic configurations may be omitted, and the dimensional ratios of the depicted parts are not necessarily accurate. In each drawing, the front-rear direction D1, the up-down direction D2, and the left-right direction D3 are as shown in each drawing.

[0014] Fig. 1 shows a state in which a flow measurement unit 10 and an inner machine case 50 included in a flow meter according to an embodiment of the present application are connected via a packing 30. Fig. 2 shows a state before the flow measurement unit 10 with the packing 30 attached is connected to the inner machine case 50.

[0015] The flow rate measurement unit 10 includes a measurement flow path section 11 having a substantially rectangular cylindrical shape. The measurement flow path section 11 has a rectangular cross section when cut along a plane defined by a vertical direction D2 and a horizontal direction D3. An inlet section 12 and an outlet section 13 are provided at both ends of the measurement flow path section 11. In the measurement flow path section 11, a fluid to be measured (e.g., fuel gas such as city gas or LP gas) flows from the inlet section 12 to the outlet section 13.

[0016] A circuit case 14 is provided at the upper center in the front-rear direction D1 of the measurement flow path section 11. The circuit case 14 has a pair of ultrasonic transducers (not shown) built in. The flow measurement unit 10 measures the flow rate of the fluid to be measured flowing in the measurement flow path section 11 based on values ​​measured by the pair of ultrasonic transducers.

[0017] A first groove 15 (see FIG. 4(a)) is formed on the rectangular outer periphery of the measurement flow path portion 11 between the front end portion 14A of the circuit case 14 and the outlet portion 13, and a second groove 16 is formed on the rectangular outer periphery of the measurement flow path portion 11 between the rear end portion 14B of the circuit case 14 and the inlet portion 12. In addition, a protrusion 17 is provided facing rearward at the rear end portion 14B of the circuit case 14.

[0018] The packing 30 has a circular shape in plan view, and three flanges 32A to 32C are formed at intervals on its peripheral edge 31. Holes 33A to 33C are drilled in the flanges 32A to 32C, respectively. The flange 32A is formed at a position 45° counterclockwise based on a radius extending upward in the vertical direction D2 from the center of the packing 30, which is circular in plan view, the flange 32B is formed at a position 45° clockwise based on the radius, and the flange 32C is formed at a position 30° counterclockwise based on a radius extending downward in the vertical direction D2 from the center of the packing 30. The flange 32C may be formed directly below the center of the packing 30.

[0019] 3(b), a rectangular hole 34 is formed in the packing 30 for mounting to the rectangular outer periphery of the measurement flow path portion 11. A fitting protrusion 35 that fits into the first groove portion 15 is formed in a peripheral wall 34A that forms the hole 34.

[0020] As shown in Fig. 2, a rib 36 is provided upright (rearward in Fig. 2) on the surface 30A of the packing 30. The rib 36 has a predetermined height from the surface 30A of the packing 30. Furthermore, a pair of opposing ribs 37 are formed around the circular outer periphery on the back side (front side in Fig. 2) of the packing 30. The pair of ribs 37 form a circular groove 38.

[0021] The inner unit case 50 is substantially rectangular parallelepiped-shaped, and its upper surface 51 is open. The inner unit case 50 includes four side walls 52A to 52D, and the rear side wall 52A is provided with a hole 53 that fits into the circular groove 38 formed on the back side of the packing 30. Three bosses 54A to 54C are erected around the hole 53 (at the rear in FIG. 2). The boss 54A is formed at a position 45° counterclockwise based on a radius extending upward from the center of the hole 53 in the vertical direction D2, the boss 54B is formed at a position 45° clockwise based on the radius, and the boss 54C is formed at a position 30° counterclockwise based on a radius extending downward from the center of the hole 53 in the vertical direction D2. The boss 54C may be formed directly below the center of the hole 53.

[0022] 1, with the flow rate measurement unit 10 connected to the inner unit case 50 via the packing 30, the inner unit case 50 is connected to an exhaust pipe (not shown) via a flange portion 56 formed by projecting outward from an upper edge portion 55 of the inner unit case 50. Then, with the exhaust pipe and the inner unit case 50 connected to the flow rate measurement unit 10 fastened together, they are housed in an outer case (not shown).

[0023] The fluid to be measured flows into the outer case from an inlet (not shown) provided in the outer case, flows into the inner case 50 through the flow measurement unit 10, and flows out of the outer case from an outlet (not shown) provided in the outer case through the exhaust pipe. During this process, the flow rate of the fluid to be measured is measured by the flow measurement unit. In this way, the inner case 50 functions to receive the fluid to be measured that has flowed through the measurement flow path section 11 of the flow measurement unit 10, and relay the fluid to be measured toward the exhaust pipe that exhausts the fluid.

[0024] The assembly of the flow rate measurement unit 10, the packing 30, and the inner unit case 50 configured as above will be described below.

[0025] Fig. 3 shows a state in which the packing 30 is correctly attached to the flow rate measurement unit 10. As shown in Fig. 3(a), when the packing 30 is moved from the outlet portion 13 toward the inlet portion 12 of the flow rate measurement unit 10 with its surface 30A facing the front end portion 14A of the circuit case 14, as shown in Fig. 3(b), the packing 30 moves to a position where the fitting protrusion portion 35 formed on the peripheral wall 34A of the hole 34 of the packing 30 fits into the first groove portion 15 of the measurement flow path portion 11 without the rib 36 formed on the surface 30A interfering with the member near the front end portion 14A of the circuit case 14.

[0026] In contrast, when the packing 30 is moved from the inlet 12 to the outlet 13 of the flow measurement unit 10 with its surface 30A facing the rear end 14B of the circuit case 14 as shown in Fig. 4(a), as shown in Fig. 4(b), the rib 36 formed on the surface 30A of the packing 30 interferes with the protrusion 17 formed on the rear end 14B of the circuit case 14, and the packing 30 does not move to a position where the fitting protrusion 35 formed on the peripheral wall 34A of the hole 34 of the packing 30 fits into the second groove 16 of the measurement flow path portion 11. This allows the operator attaching the packing 30 to the flow measurement unit 10 to know that the packing 30 is attached from the wrong direction.

[0027] Fig. 5 shows a state in which the flow rate measurement unit 10 with the packing 30 correctly attached is correctly attached to the inner unit case 50. As shown in Fig. 5(a) and Fig. 5(b), when the packing 30 is attached to the inner unit case 50 in a state in which the boss portions 54A to 54C formed on the rear side wall 52A of the inner unit case 50 are inserted into the holes 33A to 33C of the flange portions 32A to 32C of the packing 30, the flow rate measurement unit 10 is attached to the inner unit case 50 while maintaining the correct angle in the rotational direction.

[0028] 6(a) and 6(b), if the packing 30 is attached to the inner unit case 50 without inserting the bosses 54A-54C formed on the rear side wall 52A of the inner unit case 50 into the holes 33A-33C of the flanges 32A-32C of the packing 30, the flow measurement unit 10 will be attached to the inner unit case 50 at an incorrect angle in the rotational direction. This allows the operator who is attaching the flow measurement unit 10 to the inner unit case 50 via the packing 30 to know that the flow measurement unit 10 is attached at an incorrect angle in the rotational direction.

[0029] As described above, the flow meter of this embodiment is characterized by comprising a flow measurement unit 10 having a measurement flow path section 11 through which the measured fluid flows, which measures the flow rate of the measured fluid flowing through the measurement flow path section 11, a gasket 30 which is attached around the flow measurement unit 10 on the downstream side of the flow of the measured fluid and not on the upstream side of the flow of the measured fluid, and an inner unit case 50 to which the flow measurement unit 10 with the gasket 30 attached is attached from the outside, which receives the measured fluid that has flowed through the measurement flow path section 11 of the flow measurement unit 10 and relays it toward a discharge path that discharges the measured fluid.

[0030] Thus, in the flowmeter of this embodiment, the packing 30 is attached to the periphery of the flow measurement unit 10 on the downstream side of the flow of the fluid to be measured, and not to the upstream side of the flow of the fluid to be measured, which makes it possible to prevent the packing 30 from being erroneously attached to the periphery of the flow measurement unit 10. Furthermore, since the flow measurement unit 10 with the packing 30 attached is attached to the inner machine case 50 from the outside, that is, the flow measurement unit 10 without the packing 30 attached cannot be attached to the inner machine case 50 from the outside, it becomes possible to attach the flow measurement unit 10, whose attachment direction is specified, in the specified direction without fail.

[0031] The flow measurement unit 10 also has first and second groove portions 15, 16 formed on the downstream and upstream sides of its periphery, respectively, into which the gasket 30 can be fitted, and a protrusion portion 17 located between the upstream second groove portion 16 and the downstream first groove portion 15, and provided at a position where the distance between the upstream second groove portion 16 is narrower than the distance between the downstream first groove portion 15. The gasket 30 has a rib 36 of a predetermined length formed on the surface 30A opposite to the opposing surface when attached to the inner unit case 50, and when the gasket 30 is fitted into the upstream second groove portion 16, the rib 36 abuts against the protrusion portion 17, making it impossible for the gasket 30 to be fitted into the upstream second groove portion 16.

[0032] This allows the operator attaching the packing 30 to the flow rate measurement unit 10 to know that the packing 30 is being attached from the wrong direction, thereby preventing incorrect attachment.

[0033] The packing 30 has a circular shape when viewed from above, the inner unit case 50 has a circular hole 53 for attaching the circular packing 30, and a plurality of boss portions 54A-54C formed around the hole 53, the boss portions 54A-54C determining the rotation angle of the packing 30 relative to the hole 53 when the packing 30 is attached, and the packing 30 has a plurality of flange portions 32A-32C formed on a circular peripheral portion 31, and each of the plurality of flange portions 32A-32C has a hole 33A-33C formed at a position corresponding to each of the plurality of boss portions 54A-54C, which fits with each of the boss portions 54A-54C.

[0034] As a result, an operator who attaches the flow measurement unit 10 to the inner unit case 50 via the gasket 30 can attach the flow measurement unit 10 to the inner unit case 50 at an accurate angle in the rotational direction by simply attaching the flow measurement unit 10 to the inner unit case 50 with the boss portions 54A to 54C engaged with the holes 33A to 33C of the flange portions 32A to 32C.

[0035] The packing 30 is also circular in plan view and has a plurality of flange portions 32A-32C formed on a circular peripheral portion 31, and each of the plurality of flange portions 32A-32C has holes 33A-33C formed in positions corresponding to the respective boss portions 54A-54C in the inner machine case 50, which is a mounting member for the packing 30, and which has a hole 53 formed for mounting the packing 30 and a plurality of boss portions 54A-54C formed around the hole 53, the boss portions 54A-54C defining the rotation angle of the packing 30 relative to the hole 53 when the packing 30 is mounted.

[0036] As a result, an operator who attaches the flow measurement unit 10 to the inner unit case 50 via the gasket 30 can attach the flow measurement unit 10 to the inner unit case 50 at an accurate angle in the rotational direction by simply attaching the flow measurement unit 10 to the inner unit case 50 with the boss portions 54A to 54C engaged with the holes 33A to 33C of the flange portions 32A to 32C.

[0037] (Other embodiments) Fig. 7 shows a state in which a flow measurement unit 10 and an inner unit case 50' included in a flowmeter according to another embodiment different from the above embodiment are connected via a packing 30. As can be seen by comparing Fig. 1 with Fig. 7, the inner unit case 50 in the above embodiment is configured so that only one flow measurement unit 10 can be connected, whereas the inner unit case 50' in this embodiment is configured so that, for example, two flow measurement units 10 can be connected. Fig. 7 shows an example in which one flow measurement unit 10 is connected to the inner unit case 50'.

[0038] As shown in Fig. 7, two holes including hole 53' for attaching packing 30 are drilled in a rear side wall 52A' of an inner unit case 50', and packing 30 is attached to the hole other than hole 53' (not shown), and the flow rate measurement unit 10 and the inner unit case 50' are connected via the packing 30. Therefore, in the example of Fig. 7, since hole 53' is not closed by packing 30, packing 30' having a shape similar to that of packing 30 is used to close hole 53'. However, unlike packing 30, packing 30' does not have rectangular hole 34 (see Fig. 3(b)). This is because packing 30' only serves to close hole 53'.

[0039] In this embodiment, when a versatile inner unit case 50' is used, even if there is an extra hole 53' for mounting the flow measurement unit 10, the gasket 30' can be fitted into the hole 53' to close the hole 53', which is convenient.

[0040] In this embodiment, two holes are given as an example for mounting the flow rate measurement unit 10, but the number may be three or more. When the number of holes is, for example, three, the flow rate measurement unit 10 may be mounted in only one of the three holes, or in two of the three holes. The mounting positions may be selected arbitrarily.

[0041] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0042] (1) In the above embodiment, the number of holes 33A-33C and boss portions 54A-54C of the flange portions 32A-32C is three, but the number may be more or less than three. However, if one is used, when the flow measurement unit 10 is attached to the inner unit case 50 with one boss portion fitted into that one hole, deviation from the accurate angle in the rotation direction may occur, which is not preferable.

[0043] (2) In the above embodiment, the packing 30 has a circular shape in a plan view, but is not limited thereto and may have an elliptical shape, for example. However, a rectangular shape is not preferable because the seal near the apex is weak. [Explanation of symbols]

[0044] 10...flow rate measuring unit, 11...measuring flow path portion, 15...first groove portion, 16...second groove portion, 17...projection portion, 30...packing, 30A...surface, 32A to 32C...flange portion, 33A to 33C, 53...hole, 36...rib, 50...inner unit case (relay case), 54A to 54C...boss portion.

Claims

1. a flow rate measurement unit having a measurement flow path portion through which a fluid to be measured flows and configured to measure a flow rate of the fluid to be measured flowing through the measurement flow path portion; a packing attached to a downstream side of the flow of the fluid to be measured around the flow rate measurement unit and not attached to an upstream side of the flow of the fluid to be measured; a relay case that is attached from the outside to the flow rate measurement unit to which the packing is attached, receives the fluid to be measured that has flowed through the measurement flow path of the flow rate measurement unit, and relays the fluid to be measured toward a discharge path that discharges the fluid to be measured; A flow meter comprising:

2. The flow rate measurement unit includes: a groove portion into which the packing can be fitted, the groove portion being formed on each of the downstream side and the upstream side around the downstream side; a protrusion located between the upstream groove and the downstream groove, the protrusion being provided at a position where the distance between the upstream groove and the downstream groove is narrower than the distance between the upstream groove and the downstream groove; having The packing is A rib of a predetermined length is formed on the surface opposite to the surface that faces when the relay case is attached. having When the packing is fitted into the upstream groove, the rib abuts against the protrusion, and the packing cannot be fitted into the upstream groove.

2. The flow meter of claim 1.

3. The packing has a circular shape in a plan view, The relay case is A circular hole for mounting the circular packing; a plurality of bosses formed around the hole, the bosses defining a rotation angle of the packing relative to the hole when the packing is attached; having The packing is A plurality of flanges formed on the periphery of the circular shape having Each of the plurality of flange portions is formed at a position corresponding to each of the plurality of boss portions, and a hole is formed to fit with each of the boss portions.

3. The flow meter of claim 2.

4. A packing having a circular shape in a plan view, A plurality of flanges formed on the periphery of the circular shape having Each of the plurality of flange portions is an attachment member for the packing, the attachment member having a hole formed for attaching the packing and a plurality of boss portions formed around the hole, the boss portions defining a rotation angle of the packing relative to the hole when the packing is attached, and a hole is formed in each of the plurality of flange portions at a position corresponding to each of the plurality of boss portions, the boss portions fitting with each of the boss portions being formed. A packing characterized by:

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