JP6671522B2 - Ultrasonic flow switch - Google Patents

Description

  The present invention relates to an ultrasonic flow switch that operates based on a flow rate of a fluid flowing in a pipe.

  2. Description of the Related Art A flowmeter is used to accurately measure the value of the flow rate of a fluid flowing in a pipe. For example, Patent Document 1 discloses an ultrasonic flowmeter having a sensor. The sensor can measure the flow rate of the fluid flowing in the pipe using ultrasonic waves. Two sled-shaped blades projecting downward are formed on the sensor. A sheet-like silicone gel is arranged between two blades. The sensor is fixed to the outer peripheral surface of the pipe by being tightened with a tightening band until the bottom sides of the two blades contact the pipe.

JP 2001-356032 A

  Patent Literature 1 states that “Sensors are not limited to the horizontal, vertical, and inclined portions of the upper and lower portions of each pipe, and most pipes except for the distance between the two sled-shaped blades or less. It is possible to stably fix in diameter. " However, in practice, even if the sensor is fixed to a pipe that is larger than the distance between the two sled-shaped blades, the position of the ultrasonic emission surface of the sensor is not accurately determined. Therefore, it is difficult to adjust the sensitivity of the sensor. In addition, if the sensor is excessively tightened with the tightening band to stabilize the position of the ultrasonic emission surface, the ultrasonic emission surface may be damaged.

  On the other hand, it is not necessary to determine the exact flow rate of the fluid flowing through the pipe, as in the case of managing the operation status of equipment in the factory. In some cases, you may want to do it. In such a case, a flow switch that outputs an on / off signal can be used instead of a flow meter. The flow switches are attached to pipes having various outer diameters in a factory, for example. Therefore, it is desired that the flow switch can be stably attached to pipes having various dimensions.

  An object of the present invention is to provide an ultrasonic flow switch that can be stably attached to piping having various dimensions.

  (1) An ultrasonic flow switch according to the present invention is an ultrasonic flow switch attached to a pipe, and a first ultrasonic element that performs at least transmission among ultrasonic transmission and reception, and an ultrasonic transmission and reception unit. A second ultrasonic element that performs at least reception among reception, a calculation unit that calculates a flow rate of fluid in the pipe based on an output signal of at least one of the first and second ultrasonic elements, An element holding unit for holding the second ultrasonic element integrally or individually, a display unit provided on the element holding unit, for displaying the flow rate calculated by the calculation unit, and an outer surface of the pipe for holding the element holding unit and holding the element holding unit A mounting member detachably attached to the device, and a fixing member for fixing the element holding portion to the mounting member on both sides of the display portion in the axial direction of the pipe of the element holding portion, the mounting device comprising: In a state where the element holding part is not fixed by the fixing member, the displacement of the element holding part in the axial direction of the pipe and the circumferential direction of the pipe is restricted, and the displacement of the element holding part in the radial direction of the pipe is allowed. Is done.

  In this ultrasonic flow switch, ultrasonic waves are transmitted to the fluid flowing in the pipe by the first ultrasonic element, and ultrasonic waves from the fluid flowing in the pipe are received by the second ultrasonic element. A flow rate of the fluid in the pipe is calculated based on an output signal of at least one of the first and second ultrasonic elements. The first and second ultrasonic elements are integrally or individually held by the element holding section.

  A fitting is attached to the outer surface of the pipe. The element holding portion is fixed to the mounting tool by a fixing member. Here, in a state where the element holding portion is not fixed to the fixture by the fixing member, the displacement of the element holding portion in the axial direction of the pipe and the circumferential direction of the pipe is regulated, but the element holding in the radial direction of the pipe is restricted. Part displacement is allowed. In this case, the mounting position of the element holder in the axial direction and the circumferential direction of the pipe is determined by the mounting position of the mounting tool. Further, the position of the element holding portion in the radial direction of the pipe can be adjusted on the attachment.

  According to this configuration, the fixing force of the attachment to the pipe and the fixing force of the element holding portion to the attachment can be adjusted separately. Therefore, the position of the element holding portion in the axial direction and the circumferential direction of the pipe can be determined by firmly fixing the attachment to the pipe. Thereafter, by operating the fixing member, the position of the element holding unit in the radial direction of the pipe can be determined so that the element holding unit sufficiently contacts the pipe.

  Therefore, even when the element holding section is attached to a pipe having various dimensions, it is not necessary to make the element holding section excessively strongly contact the pipe, so that the position of the ultrasonic emission portion can be accurately determined without damaging the element holding section. Can be determined. In addition, when the position of the emission part of the ultrasonic wave is accurately determined, it becomes easy to adjust the reception sensitivity of the ultrasonic wave to a desired value. As a result, it becomes possible to stably attach the ultrasonic flow switch to piping having various dimensions.

  (2) The first and second ultrasonic elements have transmission / reception surfaces for transmitting or receiving ultrasonic waves, respectively, and the fixture has first and second contact surfaces capable of contacting the pipe. The first and second contact surfaces may be located on one side and the other side of the symmetry plane, respectively, so as to intersect the transmission / reception plane and to be symmetrically inclined with respect to the symmetry plane including the radial direction and the axial direction.

  According to this configuration, the first and second contact surfaces of the fixture come into contact with the pipe even when the fixture is attached to pipes having various dimensions. Thereby, the fixing force of the fixture to the pipe can be improved. The transmitting and receiving surfaces of the first and second ultrasonic elements are located between the first contact surface and the second contact surface. Therefore, even when the fitting is attached to a pipe having various dimensions, the element holding section is not displaced in the axial direction of the pipe and in the circumferential direction of the pipe on the fitting, and the element holding section is held only in the radial direction of the pipe. Can be displaced.

(3) The element holding portion has a guide portion for guiding the element holding portion so that it cannot be displaced in the axial direction and the circumferential direction and can be displaced in the radial direction when the element holding portion is not fixed by the fixing member. May be.

  According to this configuration, even when the fitting is attached to the pipe having various dimensions, the element holding portion is not displaced on the fitting in the axial direction of the pipe and the circumferential direction of the pipe, and only in the radial direction of the pipe. It becomes easier to displace the element holding part.

(4) fitting a first mounting member in contact with the outer surface of the pipe holds the element holding portion, and a second mounting member in contact with the outer surface of the pipe, the first attachment member across the pipe A fastening member for fastening the first and second attachment members to each other with the second attachment member facing the second attachment member.

  In this case, the first and second attachment members can be formed by members having high rigidity. Thereby, the fixing force of the fixture to the pipe can be further improved.

  (5) The attachment includes a fixed portion attached to the pipe, and a movable portion movably attached to the fixed portion between the first position and the second position, and the movable portion is moved to the first position. In some cases, the operation of attaching the fixed portion to the pipe is possible, and the operation of attaching the element holding portion to the fixture is not possible. When the movable portion is at the second position, the operation of attaching the fixed portion to the pipe is The operation may not be possible, and the operation of attaching the element holding unit to the attachment may be possible.

  In this case, when the element holding portion is attached to the attachment, the attachment cannot be attached to the pipe. Therefore, after attaching the attachment to the pipe, the element holding section is attached to the attachment. Thereby, the procedure for fixing the element holding portion with an appropriate fixing force can be reliably executed.

  (6) The fixing member may include first and second fixing members arranged so as to sandwich the first and second ultrasonic elements in the axial direction.

  In this case, the element holding portion can apply a fixing force in the radial direction toward the center of the pipe without tilting with respect to the pipe. Thereby, the worker can perform the attaching work of the element holding unit without being conscious of the adjustment of the inclination of the element holding unit with respect to the pipe.

  (7) The attachment and the element holding unit may be configured such that the operation of attaching the attachment to the pipe and the operation of fixing the element holding unit to the attachment by the fixing member are performed from a common direction.

  In this case, the operator can efficiently perform the operation of attaching the attachment to the pipe and the operation of fixing the element holding portion to the attachment by the fixing member from a common direction.

  It is possible to stably attach the ultrasonic flow switch to piping having various dimensions.

1 is an external perspective view of a flow switch according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view illustrating an internal configuration of the flow switch of FIG. 1. It is a perspective view of an upper clamp member. It is an end elevation and a longitudinal section of an upper clamp member. It is a top view of an upper clamp member. It is a side view of an upper clamp member. It is a perspective view of a lower clamp member. It is an end view of a lower clamp member. It is a top view of a lower clamp member. It is a side view of a lower clamp member. It is a perspective view of a sensor part. It is an end elevation of a sensor part. It is a top view of a sensor part. It is a bottom view of a sensor part. It is a side view of a sensor part. FIG. 14 is a sectional view taken along line BB of the sensor unit of FIG. 13. It is a perspective view of the upper housing | casing part and electronic circuit part of a housing | casing part. It is a perspective view of a lower housing | casing part. It is a perspective view of a path member and an ultrasonic control mechanism. It is a perspective view of a connection part. It is an exploded perspective view of a clamp part before being attached to piping. It is a perspective view of the clamp part after being attached to piping. FIG. 23 is a plan view and a side view of the clamp unit of FIG. 22. It is a perspective view of a clamp part before a sensor part is attached. FIG. 25 is a plan view and a side view of the clamp unit of FIG. 24. It is an end elevation and a sectional view of a flow switch. It is the side view and sectional drawing of a flow switch. It is the perspective view and side view of the flow switch in the state where the lower clamp member was arranged in the 1st direction. It is the perspective view and side view of the flow switch in the state where the lower clamp member was arranged in the 2nd direction. It is the side view and sectional drawing of the sensor part in the 1st modification of the installation method of an acoustic couplant. It is the side view and sectional drawing of the sensor part in the 2nd modification of the installation method of an acoustic couplant. It is the side view and sectional view of the lower housing part in the 3rd modification of the attachment system of an acoustic couplant. It is a side view and a sectional view of a flow switch in the 1st modification of a crush amount control system of an acoustic couplant. It is a side view and a sectional view of a flow switch in a 2nd modification of a crush amount control system of an acoustic couplant. It is a side view and a sectional view of a flow switch in a 3rd modification of a crush amount control system of an acoustic couplant. It is a side view and a sectional view of a flow switch in a 4th modification of a crush amount control system of an acoustic couplant. It is an end elevation and a sectional view of a flow switch in a 5th modification of a crush amount control system of an acoustic couplant. It is a figure which shows the 1st modification of the shape of a notch part. It is a figure which shows the 2nd modification of the shape of a notch part. It is a figure which shows the 3rd modification of the shape of a notch part. It is a figure which shows the 4th modification of the shape of a notch part. It is a side view of the flow switch in the 1st modification of arrangement of an ultrasonic element. It is a side view of the flow switch in the 2nd modification of arrangement of an ultrasonic element. It is an end view of the flow switch in the 1st modification of composition of a clamp part. It is an end view of the flow switch in the 2nd modification of composition of a clamp part.

[1] Schematic Configuration of Ultrasonic Flow Switch Hereinafter, an ultrasonic flow switch (hereinafter, abbreviated as a flow switch) according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of a flow switch according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing the internal configuration of the flow switch 1 of FIG. As shown in FIG. 1, the flow switch 1 includes a clamp unit 100 and a sensor unit 400.

  The clamp unit 100 includes an upper clamp member 200 and a lower clamp member 300. The clamp unit 100 is disposed so as to sandwich the pipe 2 between the upper clamp member 200 and the lower clamp member 300. Thereby, the clamp part 100 is attached to the outer peripheral surface of the pipe 2. 1 and 2, the inside diameter of the pipe 2 is d. In the present embodiment, the sensor section 400 is fixed to the upper clamp member 200 of the clamp section 100 by two sensor fixing screws 410.

  As shown in FIG. 2, the sensor section 400 includes a housing section 500, a coupling section 600, an ultrasonic control mechanism 700, and an electronic circuit section 800. The housing unit 500 includes an upper housing unit 510, a lower housing unit 520, and a path member 530. The upper housing 510 has a window 511 formed of a transparent member on the upper surface. The upper casing 510 is attached to the upper part of the lower casing 520, and the path member 530 is attached to the lower part of the lower casing 520. Thereby, a space in which liquid such as water and oil cannot enter is formed inside the casing 500.

  The coupling unit 600 includes a solid-state acoustic couplant 610 and a holding member 620 described later (see FIGS. 14 and 20). The acoustic couplant 610 is arranged between the path member 530 of the housing section 500 and the pipe 2. The holding member 620 holds the acoustic couplant 610 in the lower housing 520 of the housing 500.

  The ultrasonic control mechanism 700 is housed inside the housing section 500. The ultrasonic control mechanism 700 includes two ultrasonic elements 710 and 720, an ultrasonic shielding plate 730, and two filling members 740 and 750. The ultrasonic element 710 is arranged so as to form a predetermined angle with respect to the pipe 2, and is joined to the path member 530 by the acoustic joining agent 711. Similarly, the ultrasonic element 720 is arranged so as to form a predetermined angle with respect to the pipe 2, and is bonded to the path member 530 by the acoustic bonding agent 721.

  The ultrasonic shielding plate 730 is disposed between the ultrasonic elements 710 and 720 so as to penetrate the path member 530. The filling members 740 and 750 are formed of members different from each other. The filling member 740 is arranged so as to surround the ultrasonic elements 710 and 720. The filling member 750 is disposed above the filling member 740. The details of the ultrasonic shielding plate 730 and the filling members 740 and 750 will be described later.

  In the above arrangement, the ultrasonic wave transmitted by the ultrasonic element 710 is incident on the fluid in the pipe 2 at an incident angle θ through the path member 530 and the acoustic couplant 610. The ultrasonic wave that has passed through the fluid is reflected by the inner surface of the pipe 2 at a reflection angle θ, and is received by the ultrasonic element 720 through the acoustic couplant 610 and the path member 530.

  Similarly, the ultrasonic wave transmitted by the ultrasonic element 720 is incident on the fluid in the pipe 2 at an incident angle θ through the path member 530 and the acoustic couplant 610. The ultrasonic wave that has passed through the fluid is reflected by the inner surface of the pipe 2 at a reflection angle θ, and is received by the ultrasonic element 710 through the acoustic couplant 610 and the path member 530.

  The electronic circuit unit 800 includes a control unit 811, a storage unit 812, a display unit 821, a connection unit 830, an operation unit 840, and a display lamp 850. The control unit 811, the storage unit 812, and the display unit 821 are housed inside the housing unit 500. The connection unit 830, the operation unit 840, and the display lamp 850 are provided on the upper surface of the upper housing unit 510 of the housing unit 500.

  Various data and programs for operating the flow switch 1 are stored in the storage unit 812. The control unit 811 controls the operation of the ultrasonic elements 710 and 720, the display unit 821, and the display lamp 850 based on the data and the program stored in the storage unit 812. The control unit 811 is connected to an external device (not shown) through the connection unit 830 and the cable 3.

In the present embodiment, control unit 811 measures time difference Δt. The time difference Δt is the time until the ultrasonic wave transmitted by the ultrasonic element 710 is received by the ultrasonic element 720 and the time until the ultrasonic wave transmitted by the ultrasonic element 720 is received by the ultrasonic element 710. Is the difference. Based on the measured time difference Δt, the control unit 811 calculates the velocity _Vf of the fluid flowing in the pipe 2 by the following equation (1), and calculates the flow rate Q of the fluid flowing in the pipe 2 by the following equation (2). It is calculated by:

ここで、ｄは配管２の内径であり、θは超音波の入射角であり、Ｖ_ｓは超音波の速度である。Ｋは、配管２の断面内で所定の分布を有する流体の速度を平均速度に換算するための流量補正係数である。入射角θ、速度Ｖ_ｓおよび流量補正係数Ｋは既知である。使用者は、操作部８４０を操作することにより、配管２の内径ｄを記憶部８１２に記憶させることができる。また、使用者は、操作部８４０を操作することにより、流量のしきい値を記憶部８１２に記憶させることができる。

Here, d is the inner diameter of the pipe 2, theta is the angle of incidence of the ultrasonic wave, V _s is the velocity of ultrasonic waves. K is a flow rate correction coefficient for converting the velocity of the fluid having a predetermined distribution in the cross section of the pipe 2 into the average velocity. Incident angle theta, the speed V _s and a flow rate correction coefficient K is known. The user can cause the storage unit 812 to store the inner diameter d of the pipe 2 by operating the operation unit 840. Further, the user can cause the storage unit 812 to store the threshold value of the flow rate by operating the operation unit 840.

  The control unit 811 compares the flow rate Q calculated by the above equation (2) with the threshold value stored in the storage unit 812, and outputs an on / off signal based on the comparison result. The on / off signal is a signal for switching an external device connected to the connection unit 830 between an on state and an off state. The display lamp 850 lights up so that the on state and the off state of the external device can be identified.

The display unit 821 is arranged at a position near the window 511 of the upper housing unit 510. The display unit 821 displays various information such as the fluid velocity V _f calculated by the above equation (1), the flow rate Q calculated by the above equation (2), or the threshold value stored in the storage unit 812. can do.

[2] Clamp Section (1) Upper Clamp Member FIG. 3 is a perspective view of the upper clamp member 200. FIG. 4 is an end view and a longitudinal sectional view of the upper clamp member 200. FIG. 5 is a plan view of the upper clamp member 200. FIG. FIG. 6 is a side view of the upper clamp member 200. FIG. 4B is a cross-sectional view of the upper clamp member 200 of FIG. Hereinafter, the configuration of the upper clamp member 200 will be described with reference to FIGS.

  As shown in FIG. 3, the upper clamp member 200 includes a fixed portion 210 and a movable portion 220. The fixed part 210 is fixed to the pipe 2 of FIG. The movable part 220 is provided movably with respect to the fixed part 210. In the present embodiment, the movable part 220 is movable by sliding with respect to the fixed part 210.

  FIGS. 5A and 6A show the upper clamp member 200 when the movable portion 220 is not slid, and FIGS. 5B and 6B show the upper clamp member when the movable portion 220 is slid. 2 shows a member 200. The position of the movable part 220 in FIGS. 5B and 6B is called a first position, and the position of the movable part 220 in FIGS. 5A and 6A is called a second position.

  The fixing part 210 includes a top part 230, two end parts 240, two side parts 250, and two contact parts 260. In the present embodiment, upper surface portion 230, two end surface portions 240, two side surface portions 250, and two contact portions 260 are integrally formed of a highly rigid member such as metal.

  The upper surface portion 230 has a rectangular frame shape extending in one direction in plan view. Hereinafter, the longitudinal direction of the upper surface portion 230 in plan view is referred to as the longitudinal direction of the flow switch 1, the width direction of the upper surface portion 230 is referred to as the width direction of the flow switch 1, and the direction orthogonal to the longitudinal direction and the width direction is the flow switch 1. The vertical direction is called. When the flow switch 1 is attached to the pipe 2, the longitudinal direction of the flow switch 1 matches the axial direction of the pipe 2 (the direction in which the pipe 2 extends), and the width direction of the flow switch 1 matches the circumferential direction of the pipe 2. They substantially coincide with each other, and the vertical direction of the flow switch 1 coincides with the radial direction of the pipe 2.

  As shown in FIGS. 3 and 5A and 5B, screw holes 231 vertically penetrating are formed at both ends of the upper surface 230 in the longitudinal direction. 2 is screwed into each screw hole 231. Notches 232 are formed on the inner peripheral surfaces of both ends in the longitudinal direction of the upper surface 230. Each cutout 232 has a protruding portion 233 that protrudes downward. Thereby, two concave portions 234 are formed on the inner peripheral surfaces of both ends in the longitudinal direction of the upper surface portion 230 so as to sandwich the projecting portion 233.

  As shown in FIGS. 3 and 6A and 6B, the two end surfaces 240 extend downward from both ends of the upper surface 230 in the longitudinal direction. As shown in FIG. 4A, a polygonal notch 241 that opens downward is formed in each end surface 240. Thereby, a plurality of cut surfaces appear at the cut of the end surface 240 in the cutout 241. In this example, two vertical cut surfaces 211, one horizontal cut surface 212, and two inclined cut surfaces 213 appear on each end surface 240.

  The two vertical cut surfaces 211 extend vertically upward from the lower part of the end face part 240. The interval in the width direction between the two vertical cut surfaces 211 is larger than the outer diameter of the pipe 2. The horizontal cutting surface 212 extends horizontally in the width direction above the two vertical cutting surfaces 211. The length of the horizontal cut surface 212 in the width direction is smaller than the outer diameter of the pipe 2. One inclined cut surface 213 extends so as to be inclined from the upper portion of the one vertical cut surface 211 to one end of the horizontal cut surface 212. The other inclined cut surface 213 extends so as to be inclined from the upper portion of the other vertical cut surface 211 to the other end of the horizontal cut surface 212.

  As shown in FIGS. 3 and 4A and 4B, the two side portions 250 extend downward from both ends of the upper surface portion 230 in the width direction. As shown in FIG. 4B, two contact portions 260 are provided corresponding to the two side portions 250, respectively. Each contact part 260 includes a horizontal part 261 and an inclined part 262. The horizontal portion 261 extends inward and horizontally so as to bend from a lower end portion of the corresponding side surface portion 250. The inclined portion 262 extends inward and obliquely upward so as to be inclined from an end of the horizontal portion 261.

  The inclination angles of the one and the other inclined portions 262 are substantially equal to the inclination angles of the one and the other inclined cut surfaces 213 of the end surface portion 240, respectively. When the upper clamp member 200 is not attached to the pipe 2, the lower surfaces of the one and the other inclined portions 262 project slightly inward and downward from the one and the other inclined cut surfaces 213 of the end surface portion 240. Thereby, the lower surfaces of the one and other inclined portions 262 can abut on the outer peripheral surface of the pipe 2.

  As shown in FIG. 4B and FIGS. 6A and 6B, a plurality of through holes 263 penetrating in the vertical direction are formed in each horizontal portion 261. In this example, two through holes 263 are formed in each horizontal portion 261 so as to be arranged in the longitudinal direction at a predetermined distance. The plurality of clamp fixing screws 110 are inserted into the plurality of through holes 263 of the horizontal portion 261 from above, respectively.

  In this example, as shown in FIG. 5B and FIG. 6B, by sliding the movable portion 220 to the first position, the plurality of through holes 263 can be visually recognized from above. In this state, the plurality of clamp fixing screws 110 are inserted into the plurality of through holes 263, respectively. When the movable portion 220 is in the first position, the sensor section 400 cannot be attached to the upper clamp member 200. Therefore, when attaching the sensor unit 400 of FIG. 1 to the upper clamp member 200, the movable part 220 is returned to the second position as shown in FIGS. 5A and 6A.

  Each clamp fixing screw 110 is provided with a posture maintaining mechanism 120. Each posture maintaining mechanism 120 includes an annular member 121 and a spring member 122. The annular member 121 is fixed to a substantially central portion of the clamp fixing screw 110 in the vertical direction in a state where the clamp fixing screw 110 is inserted into the through hole 263 of the horizontal portion 261. The spring member 122 has a spiral shape, and the outer diameter of the spring member 122 is smaller than the outer diameter of the annular member 121. The spring member 122 is disposed between the horizontal portion 261 and the annular member 121 so as to urge the horizontal portion 261 and the annular member 121.

  According to this configuration, even when the upper clamp member 200 is arranged so that the longitudinal direction or the width direction is vertical, the plurality of clamp fixing screws 110 are maintained substantially perpendicular to the horizontal portion 261 by the posture maintaining mechanism 120. Is done. Accordingly, even when the upper clamp member 200 is attached to the pipe 2 extending in the vertical direction, the plurality of clamp fixing screws 110 can be easily screwed into a plurality of screw holes described later of the lower clamp member 300.

(2) Lower Clamp Member FIG. 7 is a perspective view of the lower clamp member 300. FIG. 8 is an end view of the lower clamp member 300. FIG. 9 is a plan view of the lower clamp member 300. FIG. FIG. 10 is a side view of the lower clamp member 300. Hereinafter, the configuration of the lower clamp member 300 will be described with reference to FIGS.

  As shown in FIG. 7, the lower clamp member 300 includes a bottom surface 310, two end surfaces 320, and two side surfaces 330. In the present embodiment, bottom surface portion 310, two end surface portions 320, and two side surface portions 330 are integrally formed of a highly rigid member such as metal.

  As shown in FIGS. 7 and 8, the bottom surface portion 310 has a curved shape extending in the longitudinal direction. The curvature of the upper surface of the bottom part 310 is larger than the curvature of the outer peripheral surface of the pipe 2. Therefore, the outer peripheral surface of the pipe 2 of FIG. 1 can abut on the curved upper surface of the bottom portion 310. As shown in FIGS. 7 and 9, the two side portions 330 are provided at both ends of the bottom portion 310 in the width direction. Each side portion 330 includes two protruding pieces 331, two protruding pieces 332, and one inclined piece 333.

  9 and 10, the two protruding pieces 331 of each side surface section 330 are called protruding pieces 331A and 331B, respectively, and the two protruding pieces 332 are called protruding pieces 332A and 332B, respectively. As shown in FIGS. 9 and 10, on each side surface portion 330, the protruding piece 331A, the protruding piece 332B, the inclined piece 333, the protruding piece 331B, and the protruding piece 332A are arranged in this order in the longitudinal direction.

  As shown in FIGS. 7 to 10, each end face portion 320 includes two projecting pieces 321. The two protruding pieces 321 of one end face 320 are provided so as to protrude upward from one end of the two protruding pieces 331A in the longitudinal direction. The two protruding pieces 321 of the other end face portion 320 are provided so as to protrude upward from the other ends in the longitudinal direction of the two protruding pieces 332A.

  As shown in FIG. 9, the protruding pieces 331A and 331B of each side part 330 project horizontally outward from both ends of the bottom part 310 in the width direction. The protruding pieces 332A and 332B of each side part 330 horizontally protrude outward from both ends of the bottom part 310 in the width direction. The inclined piece 333 of each side part 330 protrudes so as to incline outward and upward from both ends of the bottom part 310 in the width direction.

  As shown in FIG. 10, the protruding pieces 331A and 331B are located at substantially the same height. The projecting pieces 332A, 332B are located at substantially the same height below the projecting pieces 331A, 331B. As shown in FIG. 9, a screw hole 331h is formed in each protruding piece 331A, 331B so as to penetrate in the vertical direction. A screw hole 332h is formed in each of the projecting pieces 332A and 332B so as to penetrate in the vertical direction.

  The interval between the screw holes 331h of the protruding pieces 331A and 331B in each side portion 330 is equal to the interval between two through holes 263 in one horizontal portion 261 of the upper clamp member 200 in FIG. The interval between the screw holes 332h of the projecting pieces 332A and 332B on each side surface 330 is equal to the interval between two through holes 263 in one horizontal portion 261 of the upper clamp member 200 in FIG.

  Hereinafter, as shown in FIGS. 9 and 10, the direction of the lower clamp member 300 when the projecting piece 331A is located at one end in the longitudinal direction and the projecting piece 332A is located at the other end in the longitudinal direction is referred to as a first direction. Call. On the other hand, contrary to FIGS. 9 and 10, the direction of the lower clamp member 300 when the projecting piece 331A is located at the other end in the longitudinal direction and the projecting piece 332A is located at one end in the longitudinal direction is referred to as the second direction. Call. The operator can arrange the lower clamp member 300 in the first direction or the second direction by rotating the lower clamp member 300 by 180 degrees about an axis parallel to the vertical direction.

  According to the above configuration, when the pipe 2 is sandwiched between the upper clamp member 200 and the lower clamp member 300 with the lower clamp member 300 arranged in the first direction, the plurality of clamp fixing screws 110 shown in FIG. Are screwed into the plurality of screw holes 331h, respectively. On the other hand, when the pipe 2 is sandwiched between the upper clamp member 200 and the lower clamp member 300 with the lower clamp member 300 arranged in the second direction, the plurality of clamp fixing screws 110 in FIG. 332h.

  Here, the projecting pieces 331 and 332 are located at different heights. That is, the vertical distance from the through hole 263 to the screw hole 331h in FIG. 6A is different from the vertical distance from the through hole 263 to the screw hole 332h in FIG. 6A. Therefore, by appropriately selecting the direction in which the lower clamp member 300 is arranged in accordance with the outer diameter of the pipe 2 between the first direction and the second direction, the lower clamp member 300 can be more easily and appropriately connected to the pipe 2. Can be attached.

[3] Sensor Unit As described above, the sensor unit 400 includes the housing unit 500, the coupling unit 600, the ultrasonic control mechanism 700, and the electronic circuit unit 800. FIG. 11 is a perspective view of the sensor unit 400. FIG. 12 is an end view of the sensor unit 400. FIG. 13 is a plan view of the sensor unit 400. FIG. FIG. 14 is a bottom view of the sensor unit 400. FIG. 15 is a side view of the sensor unit 400. FIG. 16 is a sectional view taken along line BB of the sensor unit 400 in FIG.

  The housing section 500 includes a plurality of sealing members, a plurality of reinforcing members, and a plurality of screw members in addition to the upper housing section 510, the lower housing section 520, and the path member 530. FIG. 17 is a perspective view of the upper housing unit 510 and the electronic circuit unit 800 of the housing unit 500. FIG. 18 is a perspective view of the lower housing part 520. FIG. 19 is a perspective view of the path member 530 and the ultrasonic control mechanism 700. FIG. 20 is a perspective view of the coupling portion 600. Hereinafter, the configuration of each unit of the sensor unit 400 will be described with reference to FIGS.

(1) Housing part (a) Upper housing part The upper housing part 510 is formed of, for example, resin. As shown in FIGS. 11, 16, and 17, upper housing portion 510 has a substantially rectangular shape extending in the longitudinal direction in plan view. Two screw openings 512 penetrating vertically are formed in the upper housing part 510. The two screw openings 512 are arranged at both ends of the upper housing part 510 in the longitudinal direction. Each screw opening 512 includes a counterbore for locking the screw head of the sensor fixing screw 410 inserted from above from being inserted into the upper housing portion 510. The two sensor fixing screws 410 are rotatably fixed in the two screw openings 512, respectively.

  As shown in FIG. 12, FIG. 13 and FIG. 15, two bottomed screw holes 517 extending in the vertical direction are formed on each of the lower surfaces of both ends of the upper housing portion 510 in the longitudinal direction. Each screw hole 517 is arranged at a substantially central portion of the upper casing 510 in the width direction. As shown in FIGS. 12 and 13, the two screw holes 517 are arranged so as to be arranged in the width direction with the screw opening 512 interposed therebetween.

  As shown in FIGS. 11, 16 and 17, the upper housing portion 510 has a display portion opening 513, a connection portion opening 514, an operation portion opening 515, and a lamp opening 516 penetrating in the vertical direction. Is formed. The display section opening 513 is disposed at a substantially central portion of the upper housing section 510 in the longitudinal direction. The connection portion opening 514 is disposed between the one screw opening 512 and the display portion opening 513. The operation section opening 515 and the lamp opening 516 are arranged between the other screw opening 512 and the display section opening 513 so as to be arranged in the longitudinal direction.

  The display section opening 513 has a substantially rectangular shape. A display portion flange 513F that protrudes inward is formed on the inner peripheral surface of the display portion opening 513. The display unit sealing member 541 is disposed between the upper surface of the display unit flange 513F and the edge of the lower surface of the window 511. In this state, window portion 511 is fitted into display portion opening 513 from above.

  The connection portion opening 514 has a substantially circular shape. A connection portion flange 514F that protrudes inward is formed on the inner peripheral surface of the connection portion opening 514. The connection section 830 of the electronic circuit section 800 has a substantially cylindrical outer peripheral surface. A flange portion 831 protruding outward is formed on the outer peripheral surface of the connection portion opening 514. The connection portion sealing member 542 is arranged between the upper surface of the connection portion flange 514F and the lower surface of the connection portion 830 flange portion 831. In this state, the connection portion 830 is fitted into the connection portion opening 514 from above.

  The operation section opening 515 has a substantially rectangular shape. An operation portion flange 515F that protrudes inward is formed on the inner peripheral surface of the operation portion opening 515. An operating portion seal member 543 is arranged between the upper surface of the operating portion flange 515F and the lower surface of the operating portion 840 of the electronic circuit portion 800. In this state, the operation unit 840 is fitted into the operation unit opening 515 from above.

  The lamp opening 516 has a substantially rectangular shape. An inwardly protruding lamp flange 516F is formed on the inner peripheral surface of the lamp opening 516. A lamp seal member 544 is disposed between the upper surface of the lamp flange 515F and the edge of the lower surface of the display lamp 850 of the electronic circuit section 800. In this state, the display lamp 850 is fitted into the lamp opening 516 from above.

(B) Lower Housing Section The lower housing section 520 is formed of, for example, resin. As shown in FIG. 16 and FIG. 18, the lower housing part 520 includes a fitting part 521, an outer flange part 522, and an inner flange part 523. As shown in FIGS. 12 and 14, the fitting portion 521 has two fitting side surface portions 521A and two fitting end surface portions 521B. The two fitting side portions 521A are side portions at both ends of the fitting portion 521 in the width direction, respectively. The two fitting end surfaces 521B are end surfaces at both ends of the fitting portion 521 in the longitudinal direction, respectively. The upper and lower parts of the fitting part 521 are open.

  The outer peripheral surface of each fitting side surface portion 521A has a shape that fits into the inner peripheral surface of the upper surface portion 230 in the width direction of the upper clamp member 200 in FIG. As shown in FIG. 18, a plurality of hook-shaped hook portions 529 for attaching the coupling portion 600 to the housing portion 500 are formed below each fitting side surface portion 521A. Each fitting end surface portion 521B has two convex portions 524 arranged in the width direction. Each of the two protrusions 524 extends in the up-down direction and protrudes outward in the longitudinal direction. The plurality of protrusions 524 fit into the plurality of recesses 234 of the upper surface 230 of FIG. 5A, respectively.

  In the present embodiment, the lower end surface of fitting end surface portion 521B protrudes below the lower end surface of fitting side surface portion 521A. Therefore, when the flow switch 1 is attached to the pipe 2, the lower end face of each fitting end face 521 </ b> B contacts the pipe 2. Therefore, as shown in FIGS. 11, 12, 14, and 18, a pipe contact surface reinforcing sheet metal 551 for reinforcing the lower end surface is attached to each fitting end surface portion 521B.

  Each pipe contact surface reinforcing sheet metal 551 has a J-shaped cross section. Each pipe contact surface reinforcing sheet metal 551 goes around between the two convex portions 524 on the outer peripheral surface of the fitting end surface portion 521B, passes through the lower end surface of the fitting end surface portion 521B, and goes around to the inner peripheral surface of the fitting end surface portion 521B. Be placed.

  As shown in FIGS. 11, 12, 14 to 16, and 18, the outer flange portion 522 protrudes outward from the upper portion of the fitting portion 521. Two screw holes 525, screw openings 526, and two screw openings 527 are formed on each of the upper surfaces of both ends of the outer flange portion 522 in the longitudinal direction. Each screw opening 526 is disposed substantially at the center of the outer flange 522 in the width direction. As shown in FIGS. 12 and 16, the plurality of screw openings 526 penetrate vertically and communicate with the plurality of screw openings 512 of the upper housing part 510, respectively.

  As shown in FIG. 18, each of the two screw holes 525 is arranged so as to be arranged in the width direction with the screw opening 526 interposed therebetween. The plurality of screw holes 525 are formed on the upper end surface of the outer flange portion 522 and have a bottomed shape extending in the up-down direction.

  The two screw openings 527 are arranged so as to be arranged in the width direction with the two screw holes 525 and the screw openings 526 interposed therebetween. As shown in FIGS. 12 and 15, the plurality of screw openings 527 penetrate vertically and communicate with the plurality of screw holes 517 of the upper housing part 510, respectively. Each screw opening 527 includes a counterbore for locking a screw head of a case fixing screw 501, which will be described later, inserted from below into the outer flange portion 522.

  As shown in FIGS. 11, 15, 16, and 18, a lower housing part reinforcing sheet metal 552 for reinforcing the upper end surface is attached to the outer flange part 522. The lower housing part reinforcing sheet metal 552 is arranged so as to cover the upper end surface of the outer flange part 522 and the side surfaces at both ends of the outer flange part 522 in the width direction.

  As shown in FIG. 18, two screw openings 552 a, a screw opening 552 b, and two screw openings 552 c that penetrate vertically are provided at each end of the lower housing portion reinforcing sheet metal 552 in the longitudinal direction. It is formed. The plurality of screw openings 552a are arranged so as to overlap with the plurality of screw holes 525 of the outer flange portion 522, respectively. The plurality of screw openings 552b are arranged so as to overlap with the plurality of screw openings 526 of the outer flange portion 522, respectively. The plurality of screw openings 552c are arranged so as to overlap with the plurality of screw openings 527 of the outer flange 522, respectively.

  A plurality of sheet metal fixing screws 502 are respectively inserted into the plurality of screw openings 552a of the lower housing part reinforcing sheet metal 552 from above. In this state, each sheet metal fixing screw 502 is screwed into the corresponding screw hole 525 of the outer flange portion 522. Thus, the lower housing portion reinforcing sheet metal 552 is attached to the outer flange portion 522.

  As shown in FIGS. 16 and 18, an inter-casing seal member 545 is arranged on the inner edge of the upper end surface of the outer flange portion 522. Next, the upper housing part 510 is arranged on the outer flange part 522 from above. Thereafter, as shown in FIG. 14, the plurality of housing fixing screws 501 are inserted into the plurality of screw openings 512, respectively.

  In this state, each housing fixing screw 501 is screwed into the corresponding screw hole 517 through the screw opening 552c of the lower housing part reinforcing sheet metal 552. Thereby, the upper housing part 510 is attached to the lower housing part 520. As shown in FIGS. 11, 12, 15, and 16, the distal end of the sensor fixing screw 410 inserted into each screw opening 512 of the upper housing portion 510 passes through the screw opening 526 to the outer flange portion 522. Project below.

  As shown in FIGS. 16 and 18, the inner flange portion 523 protrudes inward from the inner peripheral surface of the fitting portion 521. As shown in FIG. 14, a plurality of (three in this example) positioning projections 523a, 523b, 523c projecting downward are formed on the outer edge of the lower surface of the inner flange portion 523. The two positioning projections 523a and 523b are arranged at one end of the inner flange portion 523 in the width direction so as to be arranged in the longitudinal direction. One positioning projection 523c is arranged at the other end of the inner flange portion 523 in the width direction.

  A plurality of screw holes 528 having a bottomed shape are formed on the outer edge of the lower surface of the inner flange portion 523 so as to extend in the up-down direction. Half of the plurality of screw holes 528 are arranged at one end of the inner flange portion 523 in the width direction so as to be arranged in the longitudinal direction. The other half screw holes 528 are arranged at the other end of the inner flange portion 523 in the width direction so as to be arranged in the longitudinal direction. At the inner edge of the lower surface of the inner flange portion 523, a casing path sealing member 546 is arranged. A path member 530 is attached to the lower surface of the inner flange portion 523. Details will be described later.

(C) Path Member The path member 530 is formed of a nonmetallic material having high rigidity and high sound transmission. Further, it is preferable that the path member 530 be formed of a material having high environmental resistance. In this example, the path member 530 is formed of PPS (polyphenylene sulfide) resin or ULTEM (registered trademark) resin.

  As shown in FIGS. 16 and 19, the path member 530 includes a bottom surface 531 and an outer flange 532. The bottom surface portion 531 has a substantially rectangular shape extending in the longitudinal direction in plan view. The lower surface of the bottom portion 531 has a planar shape. The lower surface of the bottom portion 531 is referred to as a pipe connection surface 530C.

  Two protruding structures 533 and 534 protruding upward are formed on the upper surface of the bottom portion 531 so as to be arranged in the longitudinal direction. In addition, a shielding plate opening 535 is formed in the bottom surface portion 531 so as to extend in the width direction and penetrates between the protruding structures 533 and 534 in the vertical direction. The ultrasonic shielding plate 730 of the ultrasonic control mechanism 700 is fitted into the shielding plate opening 535.

  In this case, the ultrasonic wave is prevented from traveling from the ultrasonic element 710 to the ultrasonic element 720 without propagating in the fluid flowing in the pipe 2. Similarly, the ultrasonic wave is prevented from traveling from the ultrasonic element 720 to the ultrasonic element 710 without propagating in the fluid flowing in the pipe 2. Thereby, the flow rate of the fluid in the pipe 2 can be calculated more accurately.

  The protruding structure 533 has an inclined surface facing obliquely upward and outward in the longitudinal direction. The protruding structure 534 has an inclined surface facing obliquely upward and outward in the longitudinal direction. The inclined surfaces of the protruding structures 533 and 534 are referred to as element coupling surfaces 530A and 530B, respectively.

  Specifically, the element coupling surface 530A has an end a1 closest to the element coupling surface 530B in the longitudinal direction, and an end a2 farthest from the element coupling surface 530B in the longitudinal direction. The element coupling surface 530A is inclined such that the end a2 is closer to the pipe than the end a1. The element coupling surface 530B has an end b1 closest to the element coupling surface 530A in the longitudinal direction, and an end b2 farthest from the element coupling surface 530A in the longitudinal direction. The element coupling surface 530B is inclined such that the end b2 is closer to the pipe than the end b1.

  The ultrasonic element 710 of the ultrasonic control mechanism 700 is joined to the element coupling surface 530A. The ultrasonic element 720 of the ultrasonic control mechanism 700 is joined to the element coupling surface 530B. In this case, the ultrasonic element 710 is arranged so as to transmit ultrasonic waves to the fluid in the pipe 2 while being inclined with respect to the pipe 2. The ultrasonic element 720 is arranged to receive an ultrasonic wave propagating through the fluid in the pipe 2 while being inclined with respect to the pipe 2. Thereby, transmission of ultrasonic waves to the fluid in the pipe 2 and reception of ultrasonic waves propagated in the fluid in the pipe 2 can be performed efficiently.

  In this way, the ultrasonic elements 710 and 720 can be supported by the common path member 530. This further reduces component costs, manufacturing costs, and assembly costs. Further, the assembly process of the flow switch 1 can be further simplified. Further, the flow switch 1 can be downsized.

  The outer flange portions 532 protrude outward from upper portions of both ends of the bottom surface portion 531 in the width direction. A plurality of (three in this example) positioning openings 536a, 536b, 536c are formed in the outer flange portion 532 so as to penetrate in the vertical direction. The two positioning openings 536a and 536b are arranged at one end of the outer flange portion 532 in the width direction so as to be arranged in the longitudinal direction. One positioning opening 536c is arranged at the other end of the outer flange 532 in the width direction. The plurality of positioning openings 536a to 536c correspond to the plurality of positioning projections 523a to 523c (FIG. 14) of the inner flange portion 523, respectively.

  Below the path member 530, a path fixing sheet metal 553 having a rectangular frame shape is arranged. The bottom surface portion 531 of the path member 530 fits on the inner peripheral surface of the path fixing sheet metal 553. The lower surface of the outer flange portion 532 of the path member 530 contacts the upper surfaces of both ends of the path fixing sheet metal 553 in the width direction.

  A plurality of screw openings 553a penetrating in the up-down direction are formed at both ends of the path fixing sheet metal 553 in the width direction. Half of the screw openings 553a among the plurality of screw openings 553a are arranged at one end of the path fixing sheet metal 553 in the width direction so as to be arranged in the longitudinal direction. The remaining half of the screw openings 553a are arranged at the other end of the path fixing sheet metal 553 in the width direction so as to be arranged in the longitudinal direction. The plurality of screw openings 553a correspond to the plurality of screw holes 528 (FIG. 14) of the inner flange portion 523, respectively.

  The plurality of positioning projections 523a to 523c of the inner flange portion 523 in FIG. 14 are fitted into the positioning openings 536a to 536c of the path member 530 from above. In this case, an inter-casing path sealing member 546 (FIG. 18) is disposed between the lower surface of the inner flange portion 523 and the upper surface of the outer flange portion 532 of the path member 530.

  The plurality of sheet metal fixing screws 503 are inserted from below into the plurality of screw openings 553a of the path fixing sheet metal 553, respectively. In this state, each sheet metal fixing screw 503 is screwed into the corresponding screw hole 528 of the inner flange portion 523. Thereby, the path member 530 and the path fixing sheet metal 553 are attached to the lower housing part 520.

  In the above configuration, the positioning mechanism is configured by the plurality of positioning projections 523a to 523C of the inner flange portion 523 and the positioning openings 536a to 536c of the path member 530. According to this configuration, the path member 530 cannot be attached to the lower housing 520 in a direction opposite to the normal direction in the longitudinal direction. Therefore, the path member 530 can be easily attached to the lower housing part 520 in a normal direction in the longitudinal direction.

  By the above-described mounting operation, the housing section 500 having a space inside is completed. In the joint portion of the plurality of members in the housing portion 500, the display portion seal member 541, the connection portion seal member 542, the operation portion seal member 543, the lamp seal member 544, the inter-housing seal member 545, and the housing An inter-path seal member 546 is provided. This prevents liquids such as water and oil from entering the space inside the housing 500.

(2) Coupling Unit As shown in FIGS. 14 and 20, the coupling unit 600 includes an acoustic couplant 610 and a holding member 620. The acoustic couplant 610 is formed of a soft elastic material made of a polymer rubber or a gel-like substance.

  The acoustic couplant 610 preferably has an acoustic impedance value between the acoustic impedance value of the path member 530 of FIG. Thereby, reflection of ultrasonic waves between acoustic couplant 610 and pipe 2 and between acoustic couplant 610 and path member 530 can be further reduced. As a result, the transmission efficiency and the reception efficiency of the ultrasonic wave by the ultrasonic elements 710 and 720 can be improved.

  The acoustic couplant 610 includes a bottom part 611 and an outer flange part 612. The bottom portion 611 has a substantially rectangular shape extending in the longitudinal direction in plan view. A slit 613 extending in the width direction is formed substantially at the center of the bottom surface portion 621 in the longitudinal direction.

  The outer flange portions 612 protrude outward from upper portions of both ends of the bottom portion 611 in the width direction. In the outer flange portion 612, a plurality of positioning openings 614 penetrating in the up-down direction are formed. Half of the positioning openings 614 among the plurality of positioning openings 614 are arranged at one end of the outer flange portion 612 in the width direction so as to be arranged in the longitudinal direction. The remaining half of the positioning openings 614 are arranged at the other end of the outer flange portion 612 in the width direction so as to be arranged in the longitudinal direction.

  The holding member 620 is formed of, for example, a resin. The holding member 620 includes a bottom part 621 and two side parts 622. The bottom surface portion 621 has a substantially rectangular shape extending in the longitudinal direction in plan view. A couplant opening 623 extending in the longitudinal direction is formed at the center of the bottom surface portion 621 in the width direction.

  A plurality of positioning projections 624 projecting upward are formed on the bottom surface portion 621. Half of the positioning projections 624 out of the plurality of positioning projections 624 are arranged at one end of the bottom portion 621 in the width direction so as to be arranged in the longitudinal direction. The remaining half of the positioning projections 624 are arranged at the other end of the bottom surface portion 621 in the width direction so as to be arranged in the longitudinal direction. The plurality of positioning projections 624 correspond to the plurality of positioning openings 614 of the acoustic couplant 610, respectively.

  The two side portions 622 are provided so as to extend upward from both ends of the bottom portion 621 in the width direction. A plurality of hook-shaped engaging portions 625 are formed on the inner surface of each side surface portion 622. The plurality of hooks 625 of the two side portions 622 correspond to the plurality of hooks 529 of the lower housing 520 (FIG. 18), respectively.

  The plurality of positioning projections 624 of the bottom portion 621 are fitted into the positioning openings 614 of the bottom portion 611 from below. Further, the bottom portion 611 is fitted into the couplant opening 623 of the bottom portion 621 from above. As a result, the acoustic couplant 610 is fixed to the holding member 620, and the coupling section 600 is completed. In this state, the plurality of hooks 625 of the two side portions 622 and the plurality of hooks 529 (FIG. 18) of the lower housing 520 are respectively connected to each other. As a result, the coupling section 600 is attached to the housing section 500.

  In this configuration, acoustic couplant 610 is held in lower housing 520 by holding member 620. The upper surface of the bottom portion 611 of the acoustic couplant 610 is in close contact with the pipe connection surface 530C of the path member 530 (FIG. 16). Further, the lower surface of the bottom portion 611 of the acoustic couplant 610 protrudes below the lower surface of the bottom portion 621 of the holding member 620. Since the operator can handle the acoustic couplant 610 together with the housing section 500, the handling of the flow switch 1 is improved. In addition, the efficiency of the mounting work of the flow switch 1 is improved.

(3) Ultrasonic Control Mechanism The ultrasonic control mechanism 700 is housed inside the casing 500. As shown in FIG. 16, the ultrasonic control mechanism 700 includes two ultrasonic elements 710 and 720, an ultrasonic shielding plate 730, and two filling members 740 and 750. Each of the two ultrasonic elements 710 and 720 has a flat plate shape.

  In addition, the ultrasonic control mechanism 700 includes an acoustic bonding agent 711 (FIG. 2) corresponding to the ultrasonic element 710, an element back sound wave blocking member 712, and an element fixing member 713. Further, the ultrasonic control mechanism 700 includes an acoustic bonding agent 721 (FIG. 2) corresponding to the ultrasonic element 720, an element back sound wave blocking member 722, and an element fixing member 723. In the present embodiment, the acoustic bonding agents 711 and 721 are grease in which fine fillers are dispersed. The element back sound wave blocking members 712 and 722 are formed of foamed rubber. The element back sound wave blocking members 712 and 722 may be formed of, for example, a porous material.

  One surface of the ultrasonic element 710 is joined to the element coupling surface 530A of the path member 530 (FIG. 16) by the acoustic bonding agent 711. An element back sound wave blocking member 712 is attached to the other surface of the ultrasonic element 710. In this state, the ultrasonic element 710 is fixed to the path member 530 by the element fixing member 713. The ultrasonic element 710 is provided so as not to block between the ultrasonic element 710 and the element coupling surface 530A.

  Similarly, one surface of the ultrasonic element 720 is joined to the element coupling surface 530B (FIG. 16) of the path member 530 by the acoustic bonding agent 721. An element back sound wave blocking member 722 is attached to the other surface of the ultrasonic element 720. In this state, the ultrasonic element 720 is fixed to the path member 530 by the element fixing member 723. The element fixing member 723 is provided so as not to block between one surface of the ultrasonic element 720 and the element coupling surface 530B.

  According to this configuration, the ultrasonic elements 710 and 720 are fixed to the path member 530 by the element fixing members 713 and 723, respectively. In this case, it is not necessary to use an adhesive to fix the ultrasonic elements 710 and 720 to the path member 530. That is, no adhesive is disposed between one surface of the ultrasonic element 710 and the element coupling surface 530A and between one surface of the ultrasonic element 720 and the element coupling surface 530B. Thereby, loss of the ultrasonic wave is prevented. As a result, the efficiency of transmission and reception of ultrasonic waves by the ultrasonic elements 710 and 720 can be improved.

  Further, ultrasonic waves are efficiently extracted from one surface of the ultrasonic element 710 by the acoustic bonding agent 711, and transmitted from the element coupling surface 530A into the path member 530. Similarly, ultrasonic waves are efficiently extracted from one surface of the ultrasonic element 720 by the acoustic bonding agent 721, and transmitted from the element coupling surface 530 </ b> B into the path member 530.

  As described above, the acoustic bonding agents 711 and 721 have a configuration in which fine fillers are dispersed in grease. In this case, the acoustic impedance of the acoustic bonding agents 711 and 721 has a value close to the acoustic impedance of the element coupling surfaces 530A and 530B of the path member 530. Thereby, the reflection of the ultrasonic wave between the ultrasonic element 710 and the element coupling surface 530A is reduced, and the reflection of the ultrasonic wave between the ultrasonic element 720 and the element coupling surface 530B is reduced. As a result, the efficiency of transmission and reception of ultrasonic waves by the ultrasonic elements 710 and 720 can be improved. The acoustic bonding agents 711 and 712 may have a configuration in which fine fillers are dispersed in an adhesive.

  Further, on the other surface of the ultrasonic element 710 and the other surface of the ultrasonic element 720, element back sound wave blocking members 712 and 722 are attached, respectively. In this case, the ultrasonic waves extracted from the other surface of the ultrasonic element 710 and the other surface of the ultrasonic element 720 are cut off. Thereby, the loss of the ultrasonic waves generated by the ultrasonic elements 710 and 720 can be reduced, and the intensity of the ultrasonic waves extracted from one surface of the ultrasonic element 710 and one surface of the ultrasonic element 720 can be increased.

  The ultrasonic shielding plate 730 is formed of the same material as the material of the element back acoustic shielding members 712 and 722. As described above, the ultrasonic shielding plate 730 is fitted into the shielding plate opening 535 of the path member 530. In this case, transmission of ultrasonic waves between the ultrasonic elements 710 and 720 in the path member 530 is blocked. This prevents the ultrasonic wave transmitted from the ultrasonic element 710 from being directly received by the ultrasonic element 720 through the inside of the path member 530. Similarly, the ultrasonic wave transmitted from the ultrasonic element 720 is prevented from passing through the path member 530 and being directly received by the ultrasonic element 710.

  The filling member 740 is formed of a material having a characteristic impedance close to the characteristic impedance of the path member 530 and having a large characteristic of attenuating (dispersing) ultrasonic waves. For example, the filling member 740 is formed of a material in which a plurality of members having different characteristic impedance values are dispersed. In this embodiment, the filling member 740 is formed of silicon in which aluminum oxide is dispersed as a filler.

  The filling member 740 is disposed so as to partially cover the periphery of the ultrasonic elements 710 and 720. In this case, the ultrasonic waves transmitted to the surroundings from the ultrasonic elements 710 and 720 without propagating in the fluid flowing in the pipe 2 are attenuated by the filling member 740. This prevents the ultrasonic wave transmitted from the ultrasonic element 710 to the surroundings from being received by the ultrasonic element 720 as a stray signal. Similarly, the ultrasonic wave transmitted from the ultrasonic element 720 to the surroundings is prevented from being received by the ultrasonic element 710 as a stray signal.

  The filling member 750 is formed of a heat insulating material. The filling member 750 is arranged above the filling member 740 and below a control board 810 of the electronic circuit section 800 described later. According to this arrangement, even when a low-temperature fluid flows in the pipe 2, heat (cold air) radiated from the pipe 2 to the control board 810 is blocked by the filling member 750. This prevents dew condensation on the control board 810. Further, since there is no need to fill the control board 810 with resin or the like in order to prevent dew condensation, the sensor unit 400 can be easily assembled and disassembled.

  According to the above configuration, the ultrasonic wave transmitted by the ultrasonic element 710 is input to the element coupling surface 530A, and is output from the pipe coupling surface 530C through the inside of the path member 530. The ultrasonic wave output from the pipe connection surface 530C is incident on the fluid in the pipe 2 through the acoustic couplant 610, is reflected on the inner surface of the pipe 2, and is again input to the pipe connection surface 530C through the acoustic couplant 610. The ultrasonic wave input to the pipe coupling surface 530C is output from the element coupling surface 530B through the inside of the path member 530, and is received by the ultrasonic element 720.

  Similarly, the ultrasonic wave transmitted by the ultrasonic element 720 is input to the element coupling surface 530B, and is output from the pipe coupling surface 530C through the inside of the path member 530. The ultrasonic wave output from the pipe connection surface 530C is incident on the fluid in the pipe 2 through the acoustic couplant 610, is reflected on the inner surface of the pipe 2, and is again input to the pipe connection surface 530C through the acoustic couplant 610. The ultrasonic wave input to the pipe coupling surface 530C is output from the element coupling surface 530A through the inside of the path member 530, and is received by the ultrasonic element 710.

(4) Electronic Circuit Unit As shown in FIGS. 16 and 17, the electronic circuit unit 800 includes a control board 810, a display board 820, a connection unit 830, an operation unit 840, and a display lamp 850. The control unit 811 includes, for example, a CPU (Central Processing Unit). The storage unit 812 includes, for example, a volatile memory or a hard disk. The control unit 811 and the storage unit 812 are mounted on the control board 810. The display unit 821 includes, for example, a segment display. The display unit 821 may include a dot matrix display. The display portion 821 is mounted on the display substrate 820.

  The control board 810 is disposed above the ultrasonic elements 710 and 720 so as to be close to the ultrasonic elements 710 and 720. Accordingly, the connection line connecting the ultrasonic elements 710 and 720 and the control board 810 is minimized. Thereby, radiation noise from the ultrasonic elements 710 and 720 can be suppressed.

  Operation unit 840 includes a plurality of operation buttons. The display lamp 850 includes a plurality of light emitting elements. Each light emitting element is, for example, an LED (light emitting diode). The operation unit 840 and the display lamp 850 are connected to the display board 820, and the display board 820 is connected to the control board 810. The control board 810 is connected to an external device (not shown) through the connection unit 830 and the cable 3.

  The control board 810, the display board 820, and the ultrasonic elements 710 and 720 acquire power from a power supply of an external device through the cable 3. In this case, it is not necessary to provide a power supply for supplying power to the control board 810, the display board 820, and the ultrasonic elements 710, 720 in the housing section 500. Therefore, the flow switch 1 can be downsized.

  The display substrate 820 is disposed at a position close to the window 511 of the upper housing 510. Thereby, the user can visually recognize the display portion 821 from the window portion 511 of the upper housing portion 510. The display unit 821 displays various information such as the fluid velocity Vf calculated by the above equation (1), the flow rate Q calculated by the above equation (2), or the threshold value stored in the memory of the control unit 811. Can be displayed.

  The display lamp 850 lights up so that the on state and the off state of the external device can be identified. For example, the display lamp 850 may be turned on when the external device is on, and may be turned off when the external device is off. Conversely, the display lamp 850 may be turned off when the external device is on, and the display lamp 850 may be turned on when the external device is off. Thus, the user can easily distinguish between the ON state and the OFF state of the external device.

  In this embodiment, display lamp 850 includes a light-emitting element that emits green light and a light-emitting element that emits red light. When the external device is on, the display lamp 850 turns on green, and when the external device is off, the display lamp 850 turns on red. Conversely, when the external device is on, the display lamp 850 may be lit red, and when the external device is off, the display lamp 850 may be lit green.

[4] Attachment of Flow Switch (1) Attachment of Clamp Section to Pipe FIG. 21 is an exploded perspective view of the clamp section 100 before being attached to the pipe 2. FIG. 22 is a perspective view of the clamp unit 100 after being attached to the pipe 2. FIGS. 23A and 23B are a plan view and a side view, respectively, of the clamp unit 100 of FIG. Hereinafter, attachment of the clamp unit 100 to the pipe 2 will be described with reference to FIGS. 21 to 23, the lower clamp member 300 is arranged in the first direction.

  First, as shown in FIGS. 22 and 23A and 23B, the movable portion 220 of the upper clamp member 200 is slid to the first position. In this case, as shown in FIG. 23A, the plurality of clamp fixing screws 110 can be visually recognized from above. Thereby, the plurality of clamp fixing screws 110 can be operated from above. In the present example, the plurality of clamp fixing screws 110 are rotatably fixed while being inserted through the plurality of through holes 263 (FIG. 21), respectively.

  Next, as shown in FIG. 21, the upper clamp member 200 and the lower clamp member 300 are arranged so as to oppose each other in the up-down direction with the pipe 2 interposed therebetween. Here, as described above, the lower surface of the inclined portion 262 of the contact portion 260 of the upper clamp member 200 projects slightly inward and downward from the inclined cut surface 213 of the end surface portion 240. Therefore, the outer peripheral surface of the upper part of the pipe 2 contacts the lower surface of the inclined part 262 of the contact part 260 of the upper clamp member 200. The outer peripheral surface of the lower part of the pipe 2 contacts the upper surface of the bottom part 310 of the lower clamp member 300.

  In this state, a plurality of clamp fixing screws 110 are operated from above by a tool such as a screwdriver. Thereby, the plurality of clamp fixing screws 110 are screwed into the screw holes 331h of the plurality of projecting pieces 331 of the lower clamp member 300, respectively. When the lower clamp member 300 is arranged in the second direction, the plurality of clamp fixing screws 110 are screwed into the screw holes 332h of the plurality of projecting pieces 332 of the lower clamp member 300, respectively.

  By screwing the plurality of clamp fixing screws 110 into the plurality of screw holes 331h, the pressure between the lower surface of the inclined portion 262 of the contact portion 260 and the outer peripheral surface of the pipe 2 increases. In this case, the inclined part 262 of the contact part 260 is deformed so as to be distorted outward and upward from the initial position. Thereby, the outer peripheral surface of the upper part of the pipe 2 comes into contact with the inclined cut surface 213 of the end surface 240 of the upper clamp member 200. The outer peripheral surface of the lower part of the pipe 2 contacts the upper surface of the bottom part 310 of the lower clamp member 300.

  According to this configuration, on the cut surface perpendicular to the pipe 2, the pipe 2 contacts the upper clamp member 200 at at least two places and the lower clamp member 300 at least one place. That is, the pipe 2 abuts on the clamp unit 100 at least three places on a cut surface perpendicular to the pipe 2. Thereby, the clamp part 100 is securely fixed to the pipe 2.

  Further, as described above, the length of the horizontal cut surface 212 in the width direction is smaller than the outer diameter of the pipe 2, and the interval between the two vertical cut surfaces 211 in the width direction is larger than the outer diameter of the pipe 2. According to this configuration, the clamp portion 100 is attached to the pipe 2 having various outer diameters in a range not less than the length in the width direction of the horizontal cut surface 212 and not more than the interval in the width direction of the two vertical cut surfaces 211. It becomes possible.

(2) Attachment of Sensor Unit to Clamp Unit FIG. 24 is a perspective view of the clamp unit 100 before the sensor unit 400 is attached. FIGS. 25A and 25B are a plan view and a side view of the clamp unit 100 of FIG. 24, respectively. Hereinafter, the attachment of the sensor unit 400 to the clamp unit 100 will be described with reference to FIGS.

  After the clamp unit 100 is attached to the pipe 2, the movable part 220 is returned to the second position as shown in FIGS. 24 and 25A and 25B. Thus, the sensor unit 400 can be attached to the clamp unit 100. The two sensor fixing screws 410 are screwed into the two screw holes 231 of the clamp unit 100, respectively, so that the sensor unit 400 is attached to the clamp unit 100.

  As described above, in the present embodiment, when the sensor unit 400 is attached to the clamp unit 100, the clamp unit 100 cannot be attached to the pipe 2. Therefore, after the clamp unit 100 is attached to the pipe 2, the sensor unit 400 is attached to the clamp unit 100. Accordingly, a procedure for fixing the sensor unit 400 with an appropriate fixing force can be reliably executed.

  In addition, since the two sensor fixing screws 410 are arranged with the ultrasonic elements 710 and 720 interposed therebetween in the longitudinal direction, the sensor unit 400 can be moved in the radial direction toward the center of the pipe 2 without inclining with respect to the pipe 2. Can be fixed. Thus, the worker can perform the mounting work of the sensor unit 400 without being conscious of adjusting the inclination of the sensor unit 400 with respect to the pipe 2.

  The outer peripheral surface of the fitting part 521 of the lower housing part 520 of the housing part 500 is fitted to the inner circumferential surfaces of both ends in the width direction of the upper surface part 230. Here, as described above, each fitting side surface portion 521A of the fitting portion 521 fits on the inner peripheral surface of the upper surface portion 230 in the width direction. Further, two concave portions 234 are formed on the inner peripheral surface of each end of the upper surface portion 230 in the longitudinal direction so as to sandwich the protruding portion 233. On each fitting end surface portion 521B of the lower housing portion 520 of the housing portion 500, a convex portion 524 that fits into each of the two concave portions 234 on the inner peripheral surface of the upper surface portion 230 is formed.

  In this case, the sensor portion 400 is displaced by the fitting portion 521 only in the radial direction of the pipe 2 without displacing the sensor portion 400 on the clamp portion 100 in the axial direction of the pipe 2 and the circumferential direction of the pipe 2. Can be. As described above, when the sensor unit 400 is attached to the clamp unit 100, the displacement of the sensor unit 400 in the longitudinal direction and the width direction is restricted. On the other hand, the vertical displacement of the sensor unit 400 is allowed.

  FIGS. 26A and 26B are an end view and a cross-sectional view of the flow switch 1, respectively. FIGS. 27A and 27B are a side view and a sectional view of the flow switch 1, respectively. 26B shows a cross-sectional view of the flow switch 1 of FIG. 26A along the line CC, and FIG. 27B shows a cross-sectional view of the flow switch 1 of FIG.

  When the sensor fixing screw 410 in FIG. 7B is tightened, the sensor unit 400 moves downward, that is, in a direction approaching the pipe 2. In this case, the acoustic couplant 610 in FIGS. 26B and 27B is crushed by the housing section 500.

  As described above, in the present embodiment, the lower end surface of the fitting end surface portion 521B protrudes below the lower end surface of the fitting side surface portion 521A. Therefore, the lower end surface (the pipe contact surface reinforcing sheet metal 551) of the fitting end surface portion 521B comes into contact with the pipe 2. Accordingly, the downward movement of the sensor unit 400 is stopped, and the crushing of the acoustic couplant 610 by the housing unit 500 is stopped. As described above, the fitting end surface portion 521B has a function of restricting the amount of crushing of the acoustic couplant 610. The fitting end face portion 521B regulates the amount of crushing of the acoustic couplant 610 at the portion where the amount of crushing of the acoustic couplant 610 is the largest.

  In the present embodiment, the amount of crushing of acoustic couplant 610 is regulated to be 10% or more and 50% or less of the thickness of acoustic couplant 610 when not crushed. In this case, the pipe connection surface 530C (FIG. 16) of the path member 530 and the pipe 2 are in close contact with a sufficient pressure. Thereby, an ultrasonic wave can be efficiently incident on the fluid in the pipe 2. On the other hand, the application of excessive pressure to the acoustic couplant 610 is suppressed. This prevents the acoustic couplant 610 from being damaged.

(3) Orientation of Lower Clamp Member When the clamp unit 100 is attached to the pipe 2, the lower clamp member 300 is arranged in the first direction, but the lower clamp member 300 is arranged in the second direction. Is also good. FIGS. 28A and 28B are a perspective view and a side view, respectively, of the flow switch 1 in a state where the lower clamp member 300 is arranged in the first direction. FIGS. 29A and 29B are a perspective view and a side view of the flow switch 1 in a state where the lower clamp member 300 is arranged in the second direction, respectively.

  As shown in FIG. 28A, when the lower clamp member 300 is arranged in the first direction, the plurality of clamp fixing screws 110 are screwed into the screw holes 331h of the plurality of projecting pieces 331, respectively. On the other hand, as shown in FIG. 29A, when the lower clamp member 300 is arranged in the second direction, the plurality of clamp fixing screws 110 are screwed into the screw holes 332h of the plurality of projecting pieces 332, respectively. I do.

  Here, the projecting piece 331 is located above the projecting piece 332. That is, the vertical distance from the through hole 263 of the horizontal portion 261 to the screw hole 332h of the protruding piece 332 is larger than the vertical distance from the through hole 263 of the horizontal portion 261 to the screw hole 331h of the protruding piece 331.

  When the outer diameter of the pipe 2 is relatively large, when the lower clamp member 300 is arranged in the second direction, the vertical distance from the through hole 263 to the screw hole 332h is larger than the length of the clamp fixing screw 110. There is. In this case, the clamp 100 cannot be attached to the pipe 2. Therefore, as shown in FIG. 28B, when the outer diameter of the pipe 2 is relatively large, the lower clamp member 300 is arranged in the first direction. Thereby, the clamp 100 can be appropriately attached to the pipe 2.

  On the other hand, when the outer diameter of the pipe 2 is relatively small, when the lower clamp member 300 is arranged in the first direction, the vertical distance from the through hole 263 to the screw hole 331h is longer than the length of the clamp fixing screw 110. May be smaller. In this case, the operation amount (the number of times of tightening) of the clamp fixing screw 110 for fixing the clamp unit 100 to the pipe 2 increases, and the burden on the operator increases. Therefore, as shown in FIG. 29B, when the outer diameter of the pipe 2 is relatively small, the lower clamp member 300 is arranged in the second direction. Thus, the clamp 100 can be attached to the pipe 2 with a low load.

[5] Modifications (1) Acoustic couplant installation method In the present embodiment, acoustic couplant 610 is held by holding member 620, and a plurality of hooks 625 of holding member 620 and a plurality of lower housing 520 are provided. The hooks 529 are respectively coupled. The acoustic couplant 610 is attached to the housing 500 by this method, but the present invention is not limited to this. The acoustic couplant 610 may be attached to the housing section 500 by another method.

  FIG. 30 is a side view and a cross-sectional view of the lower housing part 520 in a first modification of the mounting method of the acoustic couplant 610. FIG. 30B is a sectional view taken along line EE of the sensor unit 400 in FIG. In the example of FIG. 30, the upper surface of the bottom portion 611 of the acoustic couplant 610 is bonded to the lower surface of the fitting portion 521 of the lower housing portion 520 and the lower surface of the outer flange portion 532 of the path member 530 by the bonding member 421. As a result, the acoustic couplant 610 is attached to the housing section 500. In this example, the acoustic couplant 610 can be integrated with the housing section 500 with a simple configuration.

  FIG. 31 is a side view and a cross-sectional view of a lower housing part 520 in a second modification of the mounting method of the acoustic couplant 610. FIG. 31B is a cross-sectional view taken along line FF of the sensor unit 400 in FIG. In the example of FIG. 31, the upper surface of the bottom part 611 of the acoustic couplant 610 is fixed to the lower surface of the fitting part 521 of the lower housing part 520 by a plurality of screw members 422. As a result, the acoustic couplant 610 is attached to the housing section 500.

  FIG. 32 is a side view and a cross-sectional view of the lower housing part 520 in a third modification of the mounting method of the acoustic couplant 610. FIG. 32B is a sectional view taken along line GG of the sensor unit 400 in FIG. In the example of FIG. 32, the acoustic couplant 610 and the holding member 620 are integrally formed. In this state, the plurality of hooks 625 of the holding member 620 and the plurality of hooks 529 of the lower housing 520 are respectively coupled. As a result, the acoustic couplant 610 is attached to the housing section 500.

  30 and 31, the holding member 620 is not provided in the coupling portion 600. In the example of FIG. 30 or FIG. 31, instead of using the adhesive member 421 or the plurality of screw members 422, the acoustic couplant 610 and the lower casing 520 are integrally formed, so that the casing 500 Acoustic couplant 610 may be attached to the device. In the example of FIG. 32, the acoustic couplant 610 may be attached to the housing 500 by using an adhesive member or a plurality of screw members instead of using the plurality of hooks 625.

(2) Squeezing Amount Control Method In the present embodiment, the fitting end face portion 521B is a squeezing amount control portion of the acoustic couplant 610. In this method, the crushing amount of the acoustic couplant 610 is regulated by the lower end surface of the fitting end surface portion 521B coming into contact with the pipe 2, but the present invention is not limited to this. The crushing amount of the acoustic couplant 610 may be regulated by another method.

  FIG. 33 is a side view and a cross-sectional view of the flow switch 1 in a first modification of the crushing amount control method of the acoustic couplant 610. FIG. 33 (b) is a sectional view taken along line HH of the flow switch 1 of FIG. 33 (a). In the example of FIG. 33, crushing amount regulating screws 401 are provided at both ends of the casing 500 in the longitudinal direction so as to penetrate in the up-down direction. Each of the squeezing amount regulating screws 401 is disposed at a substantially central portion of the casing 500 in the width direction.

  The tip of each crushing amount regulating screw 401 protrudes below the lower surface of the housing section 500. By operating each of the crushing amount regulating screws 401 from above with a tool such as a screwdriver, it is possible to adjust the amount of protrusion of the tip of each of the crushing amount regulating screws 401 with respect to the lower surface of the housing section 500.

  When the flow switch 1 is attached to the pipe 2, the acoustic couplant 610 is crushed by the lower surface of the housing section 500. Here, when the tip of each crushing amount regulating screw 401 comes into contact with the pipe 2, the downward movement of the sensor unit 400 on the clamp unit 100 stops, and the crushing of the acoustic couplant 610 by the housing unit 500 occurs. Stop. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  FIG. 34 is a side view and a cross-sectional view of the flow switch 1 in a second modification of the crush amount control method of the acoustic couplant 610. FIG. 34B is a sectional view taken along line II of the flow switch 1 of FIG. In the example of FIG. 34, plate-shaped crush amount regulating members 402 are arranged on the outer peripheral surface of the pipe 2 so as to correspond to the lower surfaces of both ends of the housing portion 500 in the longitudinal direction, respectively. The thickness of each crush amount regulating member 402 in the vertical direction is smaller than the thickness of the bottom surface portion 611 (FIG. 20) of the acoustic couplant 610 in the vertical direction.

  When the flow switch 1 is attached to the pipe 2, the acoustic couplant 610 is crushed by the lower surface of the housing section 500. Here, when the lower surfaces of both ends of the housing portion 500 in the longitudinal direction come into contact with the upper surface of the squeezing amount regulating member 402, the downward movement of the sensor portion 400 on the clamp portion 100 is stopped, and the housing portion 500 is stopped. The crushing of the acoustic couplant 610 by 500 stops. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  In this example, the squeezing amount regulating member 402 can be arranged at a desired position between the casing 500 and the outer surface of the pipe 2. Thereby, the degree of freedom of the arrangement of the crushing amount regulating member 402 is improved.

  FIG. 35 is a side view and a cross-sectional view of the flow switch 1 in a third modification of the crushing amount control method of the acoustic couplant 610. FIG. 35B is a sectional view taken along line JJ of the flow switch 1 of FIG. In the example of FIG. 35, a plurality of (two in this example) squeezing amount regulating protrusions 101 of the upper clamp member 200 correspond to the lower surfaces of both ends of the outer flange portion 522 of the housing portion 500 in the longitudinal direction. It is formed on the upper surface.

  The tip of each squeezing amount regulating projection 101 projects above the upper surface of the clamp part 100. The amount of protrusion of the tip of each squeezing amount regulating protrusion 101 with respect to the upper surface of the clamp portion 100 is smaller than the thickness of the bottom surface portion 611 (FIG. 20) of the acoustic couplant 610 in the vertical direction.

  When the flow switch 1 is attached to the pipe 2, the acoustic couplant 610 is crushed by the lower surface of the housing section 500. Here, when the lower surfaces of both ends of the outer flange portion 522 of the housing portion 500 in the longitudinal direction contact the tips of the plurality of squeezing amount regulating protrusions 101, the downward movement of the sensor portion 400 on the clamp portion 100 stops. At the same time, the crushing of the acoustic couplant 610 by the casing 500 stops. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  In the third modification of the crush amount control method of the acoustic couplant 610, the crush amount protrusion 101 is not provided on the upper surface of the upper clamp member 200, and is not provided on the upper clamp member 200. It may be provided on the lower surface. In this example, the operator can handle the squeezing amount regulating protrusion 101 together with one of the housing section 500 and the clamp section 100, so that the handleability of the flow switch 1 is improved. In addition, the efficiency of the mounting work of the flow switch 1 is improved.

  FIG. 36 is a side view and a cross-sectional view of the flow switch 1 in a fourth modification of the crushing amount control method of the acoustic couplant 610. FIG. 36B shows a cross-sectional view of the flow switch 1 of FIG. In the example of FIG. 36, plate-shaped crush amount regulating members 403 are arranged on the upper surface of the upper clamp member 200 so as to correspond to the lower surfaces of both ends of the outer flange portion 522 of the housing portion 500 in the longitudinal direction, respectively. The thickness of each crush amount regulating member 403 in the up-down direction is smaller than the thickness of the bottom surface portion 611 (FIG. 20) of the acoustic couplant 610 in the up-down direction.

  When the flow switch 1 is attached to the pipe 2, the acoustic couplant 610 is crushed by the lower surface of the housing section 500. Here, when the lower surfaces of both ends of the outer flange portion 522 of the housing portion 500 in the longitudinal direction come into contact with the upper surface of the squeezing amount regulating member 403, the downward movement of the sensor portion 400 on the clamp portion 100 is stopped and Then, the crushing of the acoustic couplant 610 by the casing 500 stops. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  In this example, the squeezing amount regulating member 403 can be arranged at a desired position between the housing section 500 and the upper clamp member 200. Thereby, the degree of freedom of the arrangement of the crushing amount regulating member 403 is improved.

  FIG. 37 is an end view and a cross-sectional view of the flow switch 1 in a fifth modification of the crushing amount control method of the acoustic couplant 610. FIG. 37B is a sectional view taken along line LL of the flow switch 1 of FIG. In the example of FIG. 37, plate-shaped crush amount regulating members 601 are arranged on both end surfaces of the acoustic couplant 610 so as to respectively correspond to the lower surfaces of both ends of the outer flange portion 522 of the housing portion 500 in the longitudinal direction.

  The thickness of each crush amount regulating member 601 in the up-down direction is smaller than the thickness of the bottom surface portion 611 (FIG. 20) of the acoustic couplant 610 in the up-down direction. The crushing amount regulating member 601 may be adhered to the acoustic couplant 610 by an adhesive member, or may be formed integrally with the acoustic couplant 610.

  When the flow switch 1 is attached to the pipe 2, the acoustic couplant 610 is crushed by the lower surface of the housing section 500. Here, when the acoustic couplant 610 is crushed until the thickness of the bottom portion 611 of the acoustic couplant 610 becomes substantially equal to the thickness of each crushing amount regulating member 601, the lower end surface of each crushing amount regulating member 601 is connected to the pipe 2. Contact. In this case, the downward movement of the sensor unit 400 on the clamp unit 100 stops, and the crushing of the acoustic couplant 610 by the housing unit 500 stops. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  In this case, since the operator can handle the crushed amount regulating member 601 together with the acoustic couplant 610, the handleability of the flow switch 1 is improved. In addition, the efficiency of the mounting work of the flow switch 1 is improved.

(3) Shape of Notch In the present embodiment, the notch 241 of each end surface 240 of the upper clamp member 200 has two vertical cut surfaces 211, one horizontal cut surface 212, and two inclined cut surfaces. 213, but the present invention is not limited to this. The notch 241 of each end surface 240 of the upper clamp member 200 may have any one of the following first to fourth modifications, or may be a combination of the first to fourth modifications. Or may have another shape.

  FIG. 38 is a diagram illustrating a first modification of the shape of the notch 241. As shown in FIG. 38, in the first modification of the shape of the cutout portion 241, the cutout portion 241 includes a curved cut surface 212a instead of the horizontal cut surface 212 in FIG. The curved cutting surface 212a connects between the upper part of one inclined cutting surface 213 and the upper part of the other inclined cutting surface 213 so as to be curved.

  FIG. 39 is a diagram illustrating a second modification of the shape of the notch 241. As shown in FIG. 39, in the second modified example of the shape of the notch 241, the notch 241 has two steeply cut sections 213 a instead of the two cut sections 213 in FIG. And two gentle slope cut surfaces 213b.

  One steeply cut surface 213a extends inward from the upper portion of the one vertical cut surface 211 while being inclined. One gentle slope cut surface 213b extends inward while being inclined from the upper part of one sharp slope cut surface 213a. The other steep cut surface 213a extends inward from the upper portion of the other vertical cut surface 211 while being inclined. The other gentle inclined cutting surface 213b extends inward while being inclined from the upper part of the other steeply inclined cutting surface 213a. The horizontal cutting surface 212 connects between the inner ends of the two gentle inclined cutting surfaces 213b so as to extend horizontally.

  The inclination of the steeply inclined cutting surface 213a with respect to the horizontal direction is larger than the inclination of the gentlely inclined cutting surface 213b. In the example of FIG. 39, the two gentle slope cut surfaces 213b abut on the outer peripheral surface of the upper part of the pipe 2. Instead of the two gently inclined cut surfaces 213b, two steeply inclined cut surfaces 213a may be configured to contact the outer peripheral surface of the upper part of the pipe 2.

  FIG. 40 is a diagram illustrating a third modification of the shape of the notch 241. As shown in FIG. 40, in the third modification of the shape of the cutout portion 241, the cutout portion 241 does not include the horizontal cut surface 212 of FIG. Are connected to each other substantially at the center of the end surface portion 240 in the width direction.

  FIG. 41 is a diagram illustrating a fourth modification of the shape of the notch 241. As shown in FIG. 41, in the fourth modified example of the shape of the cutout portion 241, the cutout portion 241 does not include the two vertical cut surfaces 211 of FIG. One end extends to the end of the end face 240 in the width direction. The outer end of each inclined cut surface 213 may extend not to the width direction but to the end of the end surface 240 in the vertical direction.

(4) Arrangement of Ultrasonic Elements In the present embodiment, two ultrasonic elements 710 and 720 are joined to the common path member 530 and are integrally held by the common casing 500. The invention is not limited to this. The two ultrasonic elements 710, 720 may be joined to separate path members 530. In this case, the two ultrasonic elements 710 and 720 may be held by the common housing 500, or may be individually held by separate housings 500. Thereby, the degree of freedom of arrangement of the ultrasonic elements 710 and 720 is improved. Note that the electronic circuit section 800 may be held by one of the housing sections 500 or may be held by both of the housing sections 500.

  FIG. 42 is a side view of the flow switch 1 in a first modification of the arrangement of the ultrasonic elements 710 and 720. In the example of FIG. 42, two housing units 500 and two clamp units 100 are prepared. The ultrasonic element 710 is held by one casing 500 and is attached to the pipe 2 by one clamp 100. The ultrasonic element 720 is held by the other housing part 500, and is attached to the pipe 2 by the other clamp part 100. The two housing units 500 may be arranged to face each other with the pipe 2 interposed therebetween.

  FIG. 43 is a side view of the flow switch 1 in a second modification of the arrangement of the ultrasonic elements 710 and 720. In the example of FIG. 43, two housing units 500 are prepared. The lower clamp member 300 of the clamp unit 100 can attach the housing unit 500 to the pipe 2. The ultrasonic element 710 is held by one of the housing parts 500 and is attached to the pipe 2 by the upper clamp member 200. The ultrasonic element 720 is held by the other housing part 500, and is attached to the pipe 2 by the lower clamp member 300.

  In this case, the ultrasonic element 710 and the ultrasonic element 720 are arranged so as to face each other with the pipe 2 interposed therebetween. Thereby, the flow rate of the fluid in the pipe 2 can be calculated using the transmission type configuration without adding any members.

(5) Configuration of Clamp Section In the present embodiment, the upper clamp member 200 and the lower clamp member 300 of the clamp section 100 are configured to be separable, but the present invention is not limited to this. The upper clamp member 200 and the lower clamp member 300 of the clamp unit 100 may be integrally formed. Alternatively, the clamp unit 100 may not include the lower clamp member 300.

  FIG. 44 is an end view of the flow switch 1 according to a first modification of the configuration of the clamp unit 100. In the example of FIG. 44, a part of the upper clamp member 200 and a part of the lower clamp member 300 of the clamp unit 100 are joined by the hinge 111. Thus, the upper clamp member 200 and the lower clamp member 300 can sandwich the pipe 2 with a part thereof fixed. In this example, since the upper clamp member 200 and the lower clamp member 300 of the clamp unit 100 are integrally formed, the handling of the clamp unit 100 is improved.

  FIG. 45 is an end view of the flow switch 1 in a second modified example of the configuration of the clamp unit 100. In the example of FIG. 45, the clamp unit 100 does not include the lower clamp member 300 but includes the binding band 112. The upper clamp member 200 is fixed to the pipe 2 by the binding band 112. In this case, the sensor unit 400 is attached to the pipe 2 by the upper clamp member 200 and the binding band 112.

[6] Effect (1) Effect by Clamp In the flow switch 1 according to the present embodiment, the clamp 100 is attached to the outer surface of the pipe 2. The sensor unit 400 is fixed to the clamp unit 100 by the sensor fixing screw 410. Here, when the sensor unit 400 is not fixed to the clamp unit 100, the displacement of the sensor unit 400 in the axial direction of the pipe 2 and the circumferential direction of the pipe 2 is restricted, but the sensor in the radial direction of the pipe 2 is restricted. The displacement of the part 400 is allowed. In this case, the mounting position of the sensor unit 400 in the axial direction and the circumferential direction of the pipe 2 is determined by the mounting position of the clamp unit 100. Further, the position of the sensor section 400 in the radial direction of the pipe 2 can be adjusted on the clamp section 100.

  According to this configuration, the fixing force of the clamp unit 100 to the pipe 2 and the fixing force of the sensor unit 400 to the clamp unit 100 can be separately adjusted. Therefore, the position of the sensor unit 400 in the axial direction and the circumferential direction of the pipe 2 can be determined by firmly fixing the clamp unit 100 to the pipe 2. Thereafter, by operating the sensor fixing screw 410, the position of the sensor unit 400 in the radial direction of the pipe 2 can be determined so that the sensor unit 400 sufficiently contacts the pipe 2.

  Therefore, even when the sensor section 400 is attached to the pipe 2 having various dimensions, it is not necessary to make the sensor section 400 contact the pipe 2 excessively strongly. Can be determined accurately. In addition, when the position of the emission part of the ultrasonic wave is accurately determined, it becomes easy to adjust the reception sensitivity of the ultrasonic wave to a desired value. As a result, it becomes possible to stably attach the flow switch 1 to the pipes 2 having various dimensions.

  The end surface 240 of the upper clamp member 200 includes two inclined cut surfaces 213. The two inclined cut surfaces 213 intersect the ultrasonic transmission / reception surface of the sensor unit 400 and are respectively provided on one side and the other side of the symmetry plane so as to be inclined symmetrically with respect to the symmetry plane including the radial direction and the axial direction. To position.

  According to this configuration, even when the clamp 100 is attached to the pipe 2 having various dimensions, the two inclined cut surfaces 213 of the clamp 100 contact the pipe 2. Thereby, the fixing force of the clamp part 100 to the pipe 2 can be improved. The transmitting / receiving surface of the sensor unit 400 is located between the two inclined cut surfaces 213. Therefore, even when the clamp unit 100 is attached to the pipe 2 having various dimensions, the sensor unit 400 is not displaced in the axial direction of the pipe 2 and the circumferential direction of the pipe 2 on the clamp unit 100, and the radial direction of the pipe 2 is not changed. The sensor unit 400 can be displaced only at.

  Further, at least one portion of the bottom surface 310 of the lower clamp member 300 of the clamp unit 100 contacts the pipe 2. Therefore, the fixing force of the clamp part 100 to the pipe 2 can be improved regardless of the outer diameter of the pipe 2. Further, even if the clamp portion 100 is firmly fixed to the pipe 2, the pipe 2 is prevented from being deformed into an elliptical shape.

(2) Effect of Housing Unit In the flow switch 1 according to the present embodiment, the ultrasonic elements 710 and 720 are acoustically connected to the element connection surfaces 530A and 530B of the path member 530 of the housing unit 500, respectively. . The pipe connection surface 530C of the path member 530 of the housing 500 is acoustically connected to the pipe 2. According to this configuration, the ultrasonic elements 710 and 720 are supported by the path member 530 at a desired position and a desired posture. Thereby, the ultrasonic element 710 is arranged so as to transmit the ultrasonic wave to the fluid in the pipe 2 and the ultrasonic element 720 is arranged so as to receive the ultrasonic wave propagated in the fluid in the pipe 2. Becomes easier.

  The ultrasonic wave transmitted by the ultrasonic element 710 is guided to the pipe 2 through the path member 530, and the ultrasonic wave propagated in the fluid in the pipe 2 is guided to the ultrasonic element 720 through the path member 530. Here, since the path member 530 is formed of a member that transmits ultrasonic waves, the sound transmittance of the path member 530 is improved.

  As described above, it is not necessary to separately provide a member for supporting the ultrasonic elements 710 and 720 and a member for forming an ultrasonic path. This reduces component costs, manufacturing costs, and assembly costs. In addition, since the members supporting the ultrasonic elements 710 and 720 and the members constituting the path of the ultrasonic wave are integrally joined, even if there is a temperature change and a mechanical load, the ultrasonic wave is applied at the joint portion. The transmission and reception efficiency do not decrease. In addition, liquid such as water or oil does not enter the joint. Further, the assembly process of the flow switch 1 can be simplified. As a result, the flow switch 1 can be easily manufactured at low cost without lowering the transmission and reception efficiency of the ultrasonic wave.

  Further, a part of the ultrasonic control mechanism 700 and a part of the electronic circuit unit 800 are housed in a housing unit 500 including an upper housing unit 510, a lower housing unit 520, and a path member 530. The housing section 500 includes a display section seal member 541, a connection section seal member 542, an operation section seal member 543, a lamp seal member 544, an inter-chassis seal member 545, and an inter-chassis path seal member 546. A waterproof structure is provided. Thereby, the durability of the flow switch 1 such as heat resistance, water resistance and oil resistance is improved.

(3) Effect of Joint Portion In the flow switch 1 according to the present embodiment, when the clamp unit 100 is attached to the outer surface of the pipe 2 and the sensor unit 400 is held by the clamp unit 100, the ultrasonic elements 710, 720 Acoustic couplant 610 is pressed against the outer surface of pipe 2 so that is acoustically coupled to pipe 2. Here, the crushing amount of the acoustic couplant 610 in the portion where the crushing amount of the acoustic couplant 610 by the pipe 2 is the largest is regulated by the fitting end face portion 521B of the housing section 500.

  According to this configuration, even when the sensor unit 400 is attached to the pipe 2 having a relatively large outer diameter, the acoustic couplant 610 is connected to the pipe 2 so that the ultrasonic elements 710 and 720 and the pipe 2 are acoustically coupled with each other. Is pressed. On the other hand, even when the sensor unit 400 is attached to the pipe 2 having a relatively small outer diameter, the maximum amount of crushing of the acoustic couplant 610 is reliably regulated. Is prevented.

  In these cases, the maximum crushing amount of the acoustic couplant 610 is regulated to a constant value regardless of the outer diameter of the pipe 2 and the operator, and the acoustic couplant 610 has a constant thickness at a minimum thickness portion. Thereby, the acoustic coupling between the ultrasonic elements 710 and 720 and the pipe 2 is uniformly determined. As a result, the flow switch 1 can be stably mounted on the pipes 2 having various dimensions without deteriorating the uniformity of the performance of the flow switch 1.

  Further, in the present embodiment, a fitting end surface portion 521B is provided integrally with the casing 500 as a crushing amount regulating portion. When the fitting end surface portion 521B comes into contact with the outer surface of the pipe 2, the distance between the outer surface of the pipe 2 and the lower surface of the path member 530 is regulated. Thus, the amount of crushing of acoustic couplant 610 is regulated.

  In this case, there is no need to separately prepare the squeezing amount regulating section, so that the number of parts of the flow switch 1 can be reduced. Further, the operator can handle the crushing amount regulating section together with the housing section 500, so that the handleability of the flow switch 1 is improved. Further, the efficiency of the work of mounting the flow switch 1 is improved.

  Further, the acoustic couplant 610 can be attached to and detached from the housing section 500 by the holding member 620. Therefore, attachment of acoustic couplant 610 to casing 500 and removal of acoustic couplant 610 from casing 500 are facilitated. Thus, the operator can easily perform the replacement work of the acoustic couplant 610. As a result, the maintenance cost of the flow switch 1 can be reduced.

(4) Effect of Another Sensor Unit In the flow switch 1 according to the present embodiment, the operation of the clamp fixing screw 110 and the sensor fixing screw 410 can be operated from a common direction (in this example, the vertical direction). The display portion 821 is provided so as to be visible from a common direction, and the connection portion 830 is provided so that the cable 3 can be connected from a common direction.

  In this case, the operator can efficiently perform the operation of attaching the clamp unit 100 to the pipe 2 and the operation of fixing the sensor unit 400 to the clamp unit 100 by the sensor fixing screw 410 from a common direction. Further, the user can easily visually recognize the display portion 821 from a common direction. Further, the cable 3 can be easily connected to the connection portion 830 without interfering with the pipe 2.

[7] Other Embodiments (1) In the above embodiment, the sensor unit 400 calculates the flow rate Q of the fluid flowing in the pipe 2 by the equation (2) based on the propagation time difference method. It is not limited to. The sensor unit 400 may calculate the flow rate Q of the fluid flowing in the pipe 2 based on the Doppler method. In this case, one of the ultrasonic elements 710 and 720 may be configured by an ultrasonic transmitting element, and the other of the ultrasonic elements 710 and 720 may be configured by an ultrasonic receiving element.

  (2) In the above embodiment, the electronic circuit section 800 includes the display section 821 and the display lamp 850, but the present invention is not limited to this. The electronic circuit section 800 may not include the display section 821 and may not include the display lamp 850.

  (3) In the above embodiment, the lower housing part 520 and the path member 530 are formed separately, but the present invention is not limited to this. The lower housing part 520 and the path member 530 may be formed integrally. In this case, waterproofing between the lower housing part 520 and the path member 530 can be easily performed.

  (4) In the above embodiment, the waterproof part is not formed at the joint between the lower housing part 520 and the joint part 600, but the present invention is not limited to this. A waterproof structure may be formed at the joint between the lower housing 520 and the joint 600.

  (5) In the above embodiment, the housing section 500 includes one path member 530, and the path coupling member 530 is formed with the element coupling surfaces 530A and 530B and the common pipe coupling surface 530C. It is not limited to this. The housing section 500 may include two path members 530 provided separately. In this configuration, one path member 530 has an element coupling surface 530A and a pipe coupling surface 530C, and the other path member 530 has an element coupling surface 530B and a pipe coupling surface 530C.

  (6) In the above embodiment, the movable part 220 is provided on the fixed part 210 of the upper clamp member 200 of the housing part 500, but the present invention is not limited to this. The upper clamp member 200 may not have the movable portion 220 provided on the fixed portion 210. In particular, when the sensor unit 400 is attached to the clamp unit 100 and the plurality of clamp fixing screws 110 are located below the sensor unit 400, the plurality of clamp fixing screws 110 cannot be operated from above. In such a case, it is not necessary to provide the movable portion 220 on the fixed portion 210.

  (7) In the above embodiment, the posture maintaining mechanism 120 is provided for each clamp fixing screw 110, but the present invention is not limited to this. The posture maintaining mechanism 120 may not be provided for each clamp fixing screw 110. In particular, when the clamp portion 100 is attached to the horizontally extending pipe 2, the clamp fixing screws 110 are maintained substantially vertically, so that it is not necessary to provide the posture maintaining mechanism 120 for each clamp fixing screw 110.

  In addition, when the dimensions of the clamp unit 100 are small and the clamp fixing screws 110 are short, even if the clamp unit 100 is arranged so that the longitudinal direction or the width direction faces the vertical direction, each clamp fixing screw 110 is substantially vertically Will be maintained. In such a case, it is not necessary to provide the posture maintaining mechanism 120 for each clamp fixing screw 110.

  (8) In the above embodiment, by selecting the lower clamp member 300 between the first direction and the second direction, the screw holes into which the clamp fixing screws 110 are screwed are formed by the screw holes 331h and 332h. Although selected, the invention is not so limited. The screw hole into which the clamp fixing screw 110 is screwed may be selectable between the screw hole 331h and the screw hole 332h by another method.

  For example, the lower clamp member 300 may be further provided with a screw hole 331h or 332h so as to be arranged in the longitudinal direction. In this case, by selecting the position of the upper clamp member 200 with respect to the lower clamp member 300 in the longitudinal direction, the screw holes into which the clamp fixing screws 110 are screwed can be selected from the screw holes 331h and 332h.

  (9) In the above embodiment, the clamp fixing screw 110 and the sensor fixing screw 410 are provided so as to be operable from a common direction, the display unit 821 is provided so as to be visible from a common direction, and the connection unit 830 is provided in a common direction. Although the cable 3 is provided so as to be connectable from the cable, the present invention is not limited to this. The clamp fixing screw 110 and the sensor fixing screw 410 may be provided so as to be operable from another direction, the display unit 821 may be provided so as to be visible from another direction, and the connection unit 830 may be provided from another direction. The cable 3 may be provided so as to be connectable. Alternatively, the display portion 821 or the connection portion 830 may be provided rotatably with respect to the housing portion 500 so as to face an arbitrary direction.

  (10) In the above embodiment, the acoustic couplant 610 is preferably arranged so as to acoustically couple both the ultrasonic elements 710 and 720, the ultrasonic element and the pipe 2, but the present invention is not limited thereto. It is not limited to. The acoustic couplant 610 may be arranged so as to acoustically couple at least one of the ultrasonic elements 710 and 720 with the pipe 2.

  (11) In the above embodiment, the path members 530 that support the ultrasonic elements 710 and 720 and configure the path of the ultrasonic wave are provided as a part of the housing 500, but the present invention is not limited to this. . Instead of the path member 530, a member that supports the ultrasonic elements 710 and 720 and a member that configures an ultrasonic path may be separately provided in the housing section 500.

  (12) In the above-described embodiment, it is preferable that the solid-state acoustic couplant 610 is attached to the housing section 500, but the present invention is not limited to this. The acoustic couplant 610 may not be attached to the housing section 500. In this case, an acoustic couplant is arranged between the pipe 2 and the housing 500. The acoustic couplant may be in solid form, in liquid form, or in semi-liquid form.

[8] Correspondence relationship between each component of the claims and each unit of the embodiment Hereinafter, an example of correspondence between each component of the claims and each unit of the embodiment will be described. Not limited.

  In the above embodiment, the pipe 2 is an example of a pipe, the flow switch 1 is an example of an ultrasonic flow switch, and the ultrasonic elements 710 and 720 are examples of the first and second ultrasonic elements, respectively. , The control unit 811 is an example of a calculation unit and an output unit. The housing section 500 is an example of an element holding section, the clamp section 100 is an example of a fixture, the sensor fixing screw 410 is an example of a fixing member and first and second fixing members, and the inclined cut surface 213 is It is an example of a 1st and 2nd contact surface. The fitting portion 521 is an example of a guide portion, the upper clamp member 200 is an example of a first attachment member and a first holding portion, and the lower clamp member 300 is an example of a second attachment member and a second holding portion. It is an example.

  The clamp fixing screw 110 is an example of a fastening member and a screw member, the screw holes 331h and 332h are examples of first and second screw holes, respectively, and the posture maintaining mechanism 120 is an example of a posture maintaining mechanism. 263 is an example of a through hole. The spring member 122 is an example of a spring member, the fixed portion 210 is an example of a fixed portion, the movable portion 220 is an example of a movable portion, the display portion 821 is an example of a display portion, and the cable 3 is a connection line. This is an example, and the connection unit 830 is an example of a connection unit.

  Various other elements having the configuration or function described in the claims may be used as the constituent elements in the claims.

  The present invention can be effectively used for various ultrasonic flow switches.

  DESCRIPTION OF SYMBOLS 1 ... Flow switch, 2 ... Piping, 3 ... Cable, 100 ... Clamp part, 101 ... Squeeze amount control protrusion, 110 ... Clamp fixing screw, 111 ... Hinge part, 112 ... Bundling band, 120 ... Position maintaining mechanism, 121 ... Annular member, 122 spring member, 200 upper clamp member, 210 fixed portion, 211 vertical cut surface, 212 horizontal cut surface, 212a curved cut surface, 213 inclined cut surface, 213a steep cut surface , 213b ... gentle slope cut surface, 220 ... movable part, 230 ... upper surface part, 231 331h, 332h, 517, 525, 528 ... screw hole, 232, 241 ... notch, 233 ... protrusion, 234 ... recess, 240 , 320 ... end face part, 250, 330, 622 ... side face part, 260 ... contact part, 261 ... horizontal part, 262 ... inclined part, 263 ... through hole, 300 ... lower part , 310, 531, 611, 621: bottom surface, 321, 331, 331A, 331B, 332, 332A, 332B: protruding piece, 333: inclined piece, 400: sensor part, 401: crushing amount regulating screw, 402 , 403, 601: crushing amount regulating member, 410: sensor fixing screw, 421: adhesive member, 422: screw member, 500: housing part, 501: housing fixing screw, 502, 503: sheet metal fixing screw, 510 ... Upper housing part, 511: window part, 512, 526, 527, 552a to 552c, 553a: screw opening, 513: display part opening, 513F: display part flange, 514 ... connection part opening, 514F ... connection Part flange, 515 ... Opening for operation part, 515F ... Flange for operation part, 516 ... Opening for lamp, 516F ... Flange for lamp, 520 ... Lower housing Part, 521 fitting part, 521A fitting side part, 521B fitting end part, 522, 532, 612 outer flange part, 523 inner flange part, 523a, 523b, 523c, 624 positioning protrusion, 524: convex portion, 529: hook portion, 530: path member, 530A, 530B: element coupling surface, 530C: piping coupling surface, 533, 534: protruding structure, 535: opening for shielding plate, 536a to 536c, 614 ... Positioning opening, 541: Display section seal member, 542: Connection section seal member, 543: Operating section seal member, 544: Lamp seal member, 545: Seal member between casings, 546: Seal between casing paths Member, 551: sheet metal for reinforcing the pipe contact surface, 552: sheet metal for reinforcing the lower housing part, 553: sheet metal for fixing the path, 600: coupling part, 610: acoustic couplant, 613 Slit, 620 ... holding member, 623 ... opening for coplant, 700 ... ultrasonic control mechanism, 710, 720 ... ultrasonic element, 711, 721 ... acoustic bonding agent, 712, 722 ... element back sound wave blocking member, 713, 732 ... Element fixing member, 730: Ultrasonic shielding plate, 740, 750: Filling member, 800: Electronic circuit section, 810: Control board, 811: Control section, 812: Storage section, 820: Display board, 821: Display section, 830 ... Connection part, 831 ... Flange part, 840 ... Operation part, 850 ... Display lamp, a1, a2, b1, b2 ... End part

Claims (7)

An ultrasonic flow switch attached to a pipe,
A first ultrasonic element that performs at least transmission among transmission and reception of ultrasonic waves,
A second ultrasonic element that performs at least reception among transmission and reception of ultrasonic waves,
A calculating unit that calculates a flow rate of the fluid in the pipe based on an output signal of at least one of the first and second ultrasonic elements;
An element holding unit that integrally or individually holds the first and second ultrasonic elements;
A display unit provided on the element holding unit, for displaying the flow rate calculated by the calculation unit,
A fixture that holds the element holding portion and is detachably attached to the outer surface of the pipe,
On both sides of the display unit in the axial direction of the pipe of the element holding unit, a fixing member for fixing the element holding unit to the fixture,
In the state where the element holding portion is not fixed by the fixing member, the attachment restricts displacement of the element holding portion in the axial direction of the pipe and in the circumferential direction of the pipe and in the radial direction of the pipe. An ultrasonic flow switch configured to allow displacement of the element holding unit. The first and second ultrasonic elements each have a transmitting / receiving surface for transmitting or receiving ultrasonic waves,
The fitting has first and second contact surfaces capable of contacting the pipe,
The first and second contact surfaces are respectively located on one side and the other side of the symmetry plane so as to intersect the transmission / reception plane and to be symmetrically inclined with respect to a symmetry plane including the radial direction and the axial direction. The ultrasonic flow switch according to claim 1, wherein The element holding portion guides the element holding portion so as not to be displaceable in the axial direction and the circumferential direction and to be displaceable in the radial direction in a state where the element holding portion is not fixed by the fixing member. 3. The ultrasonic flow switch according to claim 1, further comprising a guide. The fitting is
A first mounting member in contact with the outer surface of the pipe while holding the element holding portion,
A second mounting member that contacts an outer surface of the pipe;
4. A fastening member for fastening the first and second attachment members to each other in a state where the first attachment member and the second attachment member face each other with the pipe interposed therebetween. The ultrasonic flow switch according to claim 1. The fitting is
A fixed portion attached to the pipe,
A movable portion movably attached to the fixed portion between a first position and a second position;
When the movable portion is at the first position, an operation of attaching the fixed portion to the pipe is possible, and an operation of attaching the element holding portion to the attachment is impossible.
The operation of attaching the fixed portion to the pipe is impossible when the movable portion is at the second position, and the operation of attaching the element holding portion to the attachment is possible. The ultrasonic flow switch according to any one of claims 4 to 7. The said fixing member contains the 1st and 2nd fixing member arrange | positioned across the said 1st and 2nd ultrasonic element in the said axial direction, The Claims any one of Claims 1-5. Ultrasonic flow switch. The attachment and the element holding portion are configured such that an operation of attaching the attachment to the pipe and a fixing operation of the element holding portion to the attachment by the fixing member are performed from a common direction. Item 7. The ultrasonic flow switch according to any one of Items 1 to 6.

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