WO2023119381A1

WO2023119381A1 - Straight flow meter sensor

Info

Publication number: WO2023119381A1
Application number: PCT/JP2021/047143
Authority: WO
Inventors: 勇気村井; 尚孝松下; 啓真外村; 克幸稲垣; 裕也石黒
Original assignee: 本多電子株式会社
Priority date: 2021-12-20
Filing date: 2021-12-20
Publication date: 2023-06-29
Also published as: JPWO2023119381A1; KR20240008421A; CN117980703A; JP7074391B1

Abstract

Provided is a straight flow meter sensor that has excellent chemical and thermal resistance and also has an excellent holding force for holding a pipe against a case. This straight flow meter sensor 11 comprises a pair of ultrasonic transducers 33, a case 20 that houses, positions and fixes same, an elastic member 2, and a pressing and fixing member 41. The elastic member 2 is fitted around a pipe 1 and has a polygon external shape when viewed from the axial direction of the pipe 1. The pressing and fixing member 41 fixes the pipe 1 to the case 20 by sandwiching the elastic member 2 and pressing the outer circumferential surface 2a including a vertex section 2b, towards the center of the elastic member. Selected drawing: FIG. 2

Description

Straight type flow meter sensor

The present invention relates to a straight type flowmeter sensor.

2. Description of the Related Art Conventionally, various ultrasonic flowmeters for measuring the flow rate of liquid have been proposed as measurement devices using ultrasonic waves. In this ultrasonic flowmeter, a flow rate measuring pipe is provided in the middle of a pipe through which liquid flows, and ultrasonic sensors are installed at upstream and downstream positions of the flow rate measuring pipe. Then, ultrasonic waves are transmitted and received using these ultrasonic sensors, and based on the time difference between the propagation time of the ultrasonic waves propagating from the upstream side to the downstream side and the propagation time of the ultrasonic waves propagating from the downstream side to the upstream side, A liquid flow rate is calculated.

This type of ultrasonic flowmeter is used, for example, to measure the flow rate of various chemicals and ultrapure water flowing in semiconductor manufacturing equipment. In particular, the chemical solution is usually at a high temperature and corrosive. Therefore, a straight tube made of a fluororesin such as PFA, which has excellent chemical resistance and heat resistance, is sometimes selected as the piping for the wetted part.

Further, as an ultrasonic flowmeter for such a PFA tube, there has conventionally been a clamp-on type that can be attached (see, for example, Patent Document 1).

A straight type flowmeter sensor of this type includes a pair of ultrasonic transducers capable of transmitting and receiving ultrasonic waves, which are arranged offset in the axial direction of the straight pipe through which the liquid flows, and a pair of ultrasonic transducers. A conventional proposal has a case that accommodates and positions and fixes the pipe, and the pipe is held and fixed by being sandwiched between a pair of case split pieces that form the case (see, for example, Patent Document 2).

Japanese Patent No. 5927394 Japanese Patent No. 6789766

However, since the PFA tube is flexible, even if it is held and fixed by directly sandwiching it between cases, it is likely to be deformed, and it is difficult to hold it firmly. Therefore, there is a possibility that the PFA tube may be axially displaced with respect to the case, which may affect the measurement accuracy. In addition, there is a possibility that water or the like may enter the interior through a gap formed at the interface between the case and the PFA tube, and it is difficult to say that the waterproofness is high.

Here, it is conceivable that the PFA tube may be held and fixed to the case via an elastic member such as rubber, but no concrete structure capable of holding it firmly has been proposed in the past.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a straight-type flowmeter sensor that is excellent in chemical resistance and heat resistance, and that is excellent in holding force of piping to a case.

In order to solve the above problems, the invention according to claim 1 provides a pair of ultrasonic transducers capable of transmitting and receiving ultrasonic waves, which are arranged offset in the axial direction of a straight fluororesin pipe through which a fluid flows. and a case for housing and positioning and fixing the pair of ultrasonic transducers, wherein the sensor is fitted on the pipe and has a polygonal outer shape when viewed from the axial direction of the pipe. An elastic member having a shape, and a press fixing member that sandwiches the elastic member and presses an outer peripheral surface including a vertex portion of the elastic member toward the center of the elastic member, thereby fixing the pipe to the case. The gist thereof is a straight-type flowmeter sensor characterized by:

Therefore, according to the first aspect of the invention, the pressing and fixing member sandwiches and presses the elastic member fitted on the pipe, whereby a holding force acts on the outer peripheral surface of the pipe via the elastic member that is in close contact with the pipe. As a result, the pipe is held and fixed to the case. Here, the elastic member has a polygonal outer shape when viewed from the axial direction of the pipe, and the pressing and fixing member has an outer peripheral surface including the vertex of such a polygonal elastic member directed toward the center of the elastic member. and press. Therefore, the pressing force from the pressing and fixing member efficiently acts on the elastic member to compress the elastic member, thereby firmly holding and fixing the pipe to the case with a sufficient holding force. Therefore, it is possible to prevent the pipe from being displaced in the axial direction, and also to prevent water or the like from entering through the gap between the case and the pipe.

The gist of the invention according to claim 2 is that in claim 1, the elastic member is externally fitted to a region outside the case of the pipe.

Therefore, according to the second aspect of the invention, it is possible to reduce the size of the case itself because the elastic member does not have to be built in the case.

The gist of the invention according to claim 3 is that in claim 2, a projection is formed on the end surface of the case, and the elastic member and the projection are sandwiched between the pressing and fixing members.

Therefore, according to the third aspect of the invention, the pressing and fixing member sandwiches the projection together with the elastic member, so that the pipe is held and fixed to the case more firmly.

The gist of the invention according to claim 4 is that in claim 1, the elastic member is externally fitted to a region inside the case of the pipe.

Therefore, according to the fourth aspect of the present invention, since the elastic member is housed in the case and is not visible from the outside, it is possible to achieve a neat overall design with less protruding portions.

According to a fifth aspect of the present invention, in the first or second aspect, a protrusion is formed on the outer side surface of the pressing and fixing member, and the protrusion is sandwiched between the cases.

Therefore, according to the fifth aspect of the invention, the pipe is held and fixed to the case more firmly by sandwiching the projection together with the elastic member in the case.

The invention according to claim 6 is characterized in that, in any one of claims 1 to 5, the pressing fixing member is provided separately from the case.

Therefore, according to the sixth aspect of the invention, since it can be manufactured through a process different from that of the case, it has a complicated shape suitable for pressing compared to, for example, one formed integrally with the case. It has the advantage of being easy to Moreover, since the pressing force does not depend on the screw tightening force of the case, the case is less likely to be thermally deformed even when a high-temperature liquid is flowed through the pipe. In addition, the risk of reduction in pressing force due to thermal deformation is eliminated.

According to a seventh aspect of the present invention, in the first, second or fourth aspect, the press fixing member is formed integrally with a part of the case.

Therefore, according to the seventh aspect of the invention, it is possible to reduce the number of parts and the number of assembling man-hours compared to, for example, a case formed separately from the case.

According to an eighth aspect of the invention, in any one of the first to seventh aspects, the gist is that the elastic member has a polygonal shape having an even number of the vertex portions.

Therefore, according to the eighth aspect of the invention, it is easier to form the elastic member itself and the pressing and fixing member having a shape corresponding thereto, compared to, for example, a polygonal shape having an odd number of vertices. can. Moreover, since the pressing force can be applied from two diagonal directions, the pressing force can be applied effectively.

According to a ninth aspect of the invention, in any one of the first to eighth aspects, the elastic member has a quadrangular or hexagonal outer shape when viewed from the axial direction of the pipe, The fixing member is configured by combining a pair of split pieces, and an elastic member holding member comprising a plurality of pressing surfaces contacting the apex portion and the outer peripheral surface of the elastic member on the joint surfaces of the pair of split pieces. A concave portion is formed, and of the plurality of pressing surfaces, the one connected to the opening edge of the elastic member holding concave portion is inclined so as to face the joint surface side, and the elastic member is sandwiched between the pair of split pieces. The gist of this is that sometimes the center of the pipe is positioned on the extension of the joint surface.

Therefore, according to the ninth aspect of the invention, by holding the elastic member in the elastic member holding recesses of the pair of split pieces and joining the split pieces together in this state, the plurality of pressing surfaces are formed at the vertex portions of the elastic members. contact the outer peripheral surface including As a result, the outer peripheral surface including the apex portion of the elastic member is efficiently and reliably pressed toward the center of the elastic member, and the pressing force can be applied effectively. In addition, since the pressing surface located near the opening of the elastic member holding recess is inclined to face the joint surface side, it is possible to easily hold the square or hexagonal elastic member in the elastic member holding recess. can. Furthermore, when the elastic member is sandwiched between the pair of split pieces, the structure in which the center of the pipe is positioned on the extension of the joint surface is easy to design, and the pressing force is evenly applied to the elastic member. It has the advantage of being easy to add.

The invention according to claim 10 is the invention according to claim 3 or 5, wherein the projection is a flange portion projecting so as to surround the pipe from the end surface of the case or the outer surface of the pressing and fixing member. This is the gist of it.

Therefore, according to the tenth aspect of the present invention, the pressure fixing member sandwiches the flange portion having such a shape together with the elastic member, so that the pipe is held and fixed to the case more firmly.

According to an eleventh aspect of the invention, in the ninth aspect, the pressing and fixing member is a pressing and fixing ring formed in a substantially annular shape by combining a pair of split pieces, and the pair of split pieces are provided at both end portions. has a first connecting portion and a second connecting portion, respectively, and in the first connecting portion, the engaging claw protruding from one of the split pieces is connected to the engaging claw provided on the other split piece The pair of split pieces are connected to each other by engaging with the holes and screwing a fastening member inserted through one of the split pieces into the other split piece at the second connecting portion. is the gist of it.

Therefore, according to the eleventh aspect of the invention, the elastic member is secured by tightening the fastening member provided at the second connecting portion while the elastic member is arranged in the pressing and fixing ring constituted by the pair of split pieces. The pressing force can be efficiently and reliably applied in the central direction.

A twelfth aspect of the invention is directed to any one of the first to eleventh aspects, wherein reinforcing ribs extending in the circumferential direction of the pipe are protruded from the outer surface of the pressing and fixing member. This is the gist.

Therefore, according to the twelfth aspect of the invention, the press fixing member is reinforced by the reinforcing ribs extending in the circumferential direction of the pipe. As a result, even if the fastening member is strongly tightened, the pressing and fixing member is less likely to deform, and the elastic member can be reliably pressed with a sufficient pressing force.

The gist of the invention according to claim 13 is that in any one of claims 1 to 12, the pressing and fixing member includes the elastic member.

Therefore, according to the thirteenth aspect of the invention, since the elastic member is contained in the pressing and fixing member, deformation in the direction of both end surfaces during pressing is suppressed. Pressure can be applied centrally.

As described in detail above, according to the first to thirteenth aspects of the present invention, it is possible to provide a straight type flowmeter sensor that is excellent in chemical resistance and heat resistance and that is excellent in holding force of piping to the case.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the straight type|mold flowmeter sensor of 1st Embodiment which actualized this invention. FIG. 2 is a partially exploded perspective view showing the straight type flow meter sensor of the first embodiment; FIG. 2 is a partially exploded longitudinal sectional view showing the straight-type flow meter sensor of the first embodiment; The perspective view which shows the 1st division|segmentation piece of the press fixing ring in the straight type flowmeter sensor of the modification of 1st Embodiment. The perspective view which shows the 2nd split piece of the said press fixing ring. The perspective view which shows the 1st division|segmentation piece and the 2nd division|segmentation piece of the said press fixing ring. The perspective view which shows the 1st division|segmentation piece and the 2nd division|segmentation piece of the said press fixing ring. FIG. 5 is a schematic diagram for explaining how the elastic member is sandwiched between the first split piece and the second split piece of the pressing and fixing ring. FIG. 4 is a schematic diagram for explaining a state when an elastic member is sandwiched between the first split piece and the second split piece of the pressing and fixing ring; The exploded perspective view which shows the straight type|mold flowmeter sensor of 2nd Embodiment. FIG. 10 is an exploded vertical cross-sectional view showing a straight type flowmeter sensor according to a second embodiment; The exploded perspective view which shows the straight type|mold flowmeter sensor of 3rd Embodiment. FIG. 11 is an exploded cross-sectional view showing a straight-type flowmeter sensor according to a third embodiment; The exploded perspective view which shows the straight type|mold flowmeter sensor of 4th Embodiment. FIG. 11 is an exploded cross-sectional view showing a straight-type flowmeter sensor according to a fourth embodiment; (a) to (d) are schematic diagrams showing a pair of split pieces in another embodiment.

[First Embodiment]

A first embodiment in which the present invention is embodied in a straight type flowmeter sensor will be described in detail below with reference to FIGS. 1 to 9. FIG.

1 to 3 are perspective views of a straight type flow meter sensor 11 of this embodiment, FIG. 2 is a partially exploded perspective view of the same, and FIG. 3 is a partially exploded longitudinal sectional view of the same.

As shown in FIGS. 1 to 7 and the like, the straight-type flowmeter sensor 11 of this embodiment is a clamp-on type ultrasonic flowmeter sensor that can be attached to a straight-shaped pipe 1 .

The straight pipe 1 to which the straight flowmeter sensor 11 is attached is not particularly limited, but preferably a tube made of a resin material having excellent chemical resistance and heat resistance. Specifically, a fluororesin tube made of PFA or the like and having a diameter of about several millimeters is used as the pipe 1 here.

As shown in FIG. 3 and the like, this straight type flowmeter sensor 11 includes a pair of ultrasonic transducers 33, a case 20, a square rubber block 2 as an elastic member, a pressing fixing ring 41 as a pressing fixing member, and the like. ing. A sensor module assembled by a transducer housing box 31, a pair of ultrasonic transducers 33, and a pair of shoes 32 is attached to a predetermined location in the case inner region R2 of the pipe 1. As shown in FIG.

The pair of shoes 32 is a member that functions as a transducer support and has an ultrasonic transducer 33 capable of transmitting and receiving ultrasonic waves. A pair of shoes 32 are arranged on the outer peripheral surface of the pipe 1 so as to substantially face each other in order to configure the transmission type straight flow meter sensor 11 . The pair of shoes 32 support the ultrasonic transducer 33 in such a manner that the ultrasonic waves can be obliquely incident on the straight pipe 1 through which the fluid flows, and are offset in the axial direction of the pipe 1. are placed. The ultrasonic vibrator 33 is made of a disc-shaped ceramic sintered body and is adhered to and supported by the shoe 32 . In this embodiment, for example, the ultrasonic transducer 33 that generates ultrasonic waves of 2 MHz is used, but it is of course possible to generate other frequencies. The ultrasonic wave emitting surfaces of these ultrasonic transducers 33 are arranged in a state of being inclined toward the direction of the straight pipe 1 .

The vibrator housing box 31 is a rectangular box-shaped container, and plays a role of housing a pair of shoes 32 inside itself and holding and fixing them in correct positions with respect to the pipe 1 . A pair of shoes 32 are housed in the internal space of the transducer housing box 31 in a state in which the piping 1 is sandwiched from both sides and fixed. As a result, the ultrasonic transducer 33 is held and fixed to the transducer housing box 31 and the pipe 1 so as not to be displaced.

As shown in FIGS. 1 to 3, the case 20 is a rectangular box-shaped container that is slightly larger than the transducer housing box 31, and has an outer side that houses and protects the transducer housing box 31 and the like constituting the sensor module. Acts as a case. Although the material for forming the case 20 is not particularly limited, for example, a resin such as PPS is used. The case 20 is composed of a case main body 21 and a lid portion 28 .

The case main body 21 has a rectangular box shape with an open top side, and has an accommodation space 22 therein. The case body 21 has a pair of end faces 21a and 21b. Piping insertion portions protrude from the central portions of the outer surfaces of these

end surfaces

21a and 21b. A flange portion 25 (protrusion) having a circular shape in a front view is integrally formed at the tip of the pipe insertion portion. An insertion hole 23 is formed to allow communication between the inside and the outside of the case body 21 , and both ends of the pipe 1 are inserted through the insertion hole 23 . The flange portion 25 of the pipe insertion portion surrounds the outer peripheral surface of the pipe 1 that is inserted. A vibrator housing box 31 is fixedly arranged substantially in the central portion of the housing space 22 of the case body 21 . A lid portion 28 is arranged in the opening of the case body 21, and the lid portion 28 is fixed to the case body 21 using a fastening member such as a screw (not shown).

As shown in FIGS. 2 and 3, a square rubber block 2 as an elastic member has a center hole 3 and is fitted onto a case outer region R1 of the pipe 1. As shown in FIGS. The square rubber block 2 of the present embodiment is formed using a chemical-resistant and heat-resistant material such as hard fluororubber. Suitable fluororubbers include, for example, vinylidene fluoride (FKM), tetrafluoroethylene-propylene (FEPM), and tetrafluoroethylene-purple vinyl ether (FFKM) rubbers. In this embodiment, a square rubber block 2 made of FKM rubber is used. The rectangular rubber block 2 has a polygonal outer shape when viewed from the axial direction of the pipe 1, and in this embodiment, has a square shape with a side length of about 9 mm. In addition, the length of the square rubber block 2 in the axial direction is set longer than the length of one side of the square in order to provide a sufficient holding force, and in this embodiment is set to, for example, about 10 mm to 15 mm. The square rubber block 2 is arranged so as to contact the flange portion 25 at the tip of the pipe insertion portion. In this case, an O-ring (not shown) may be interposed between the square rubber block 2 and the flange portion 25 in order to improve waterproofness.

As shown in FIGS. 1 to 3, a pressure fixing ring 41 as a pressure fixing member is constructed by combining and joining a pair of divided pieces 42 having substantially semicircular shapes and having the same shape. None. These split pieces 42 are resin molded products formed using a heat-resistant resin material such as PPS. An elastic member holding recess 40 for holding the square rubber block 2 is formed on the joint surfaces of the pressing and fixing rings 41 . The elastic member holding recess 40 has four pressing surfaces 44 on its inner surface. These pressing surfaces 44 contact the vertex portion 2b and the outer peripheral surface 2a of the square rubber block 2. As shown in FIG. Two substantially V-shaped pressing surfaces 44 are formed on the inner surface of each split piece 42 . The split piece 42 has a first wall portion 43 and a second wall portion 46 on both sides of the pressing surface 44 . A flange accommodation groove 45 is formed between the pressing surface 44 and the second wall portion 46 . The inner edge portion of the second wall portion 46 forms part of the pipe insertion hole and is narrower than the portion of the flange accommodation groove 45 . The inner edge of the first wall portion 43 also forms part of the pipe insertion hole.

A pair of split pieces 42 constituting the press fixing ring 41 sandwiches the square rubber block 2 and the flange portion 25 arranged in contact therewith to fix them so that they cannot be displaced. At this time, the first wall portion 43 of the split piece 42 covers one end surface of the square rubber block 2 , and the second wall portion 46 covers the other end surface of the square rubber block 2 . That is, the pressing and fixing ring 41 holds the rectangular rubber block 2 in a state of being enclosed therein. The dimensions of the rectangular central hole formed in the central portion of the pressing and fixing ring 41 are slightly smaller than the external dimensions of the square rubber block 2, and in this embodiment, they are squares with a side length of about 8 mm. Therefore, mainly the vertex portion 2b of the square rubber block 2 arranged in the rectangular center hole is pressed toward the center of the square rubber block 2. As shown in FIG. The pipe 1 is thereby fixed to the case 20 . The pair of split pieces 42 can be joined to each other by any method, such as adhesion, welding, caulking, or screwing.

Here, a pressing fixing ring 41 of a modified example of the present embodiment will be described with reference to FIGS. 4 to 9. FIG. FIG. 4 is a perspective view showing the first split piece 42A of the press fixing ring 41, and FIG. 5 is a perspective view showing the second split piece 42B. 6 and 7 are perspective views showing the first split piece 42A and the second split piece 42B arranged to face each other. 8 and 9 are schematic diagrams showing the state before the square rubber block 2 is sandwiched between the first split piece 42A and the second split piece 42B, and schematic diagrams showing the square rubber block 2 sandwiched. It should be noted that the configuration common to the pressing and fixing ring 41 of FIGS. 1 to 3 described above is omitted from detailed description instead of attaching common member numbers.

The pressing and fixing ring 41 of the modified example is configured in a substantially annular shape by combining a first split piece 42A and a second split piece 42B. 1 to 3, the structure of the pair of split pieces 42 is basically the same. However, the structures of the first split piece 42A and the second split piece 42B of the modified example are slightly different. 42 A of 1st division|segmentation pieces and the 2nd division|segmentation piece 42B have the 1st connection part C1 and the 2nd connection part C2 in both ends, respectively. An engagement protrusion 51 is formed on the first connection portion C1 side of the first split piece 42A, and a rectangular engagement hole 52 is provided in the engagement protrusion 51 . A bolt insertion hole 47 is formed on the second connection portion C2 side of the first split piece 42A. On the other hand, an engaging claw 53 that can be engaged with the engaging hole 52 of the first split piece 42A protrudes from the second split piece 42B on the side of the first connecting portion C1. A bolt insertion hole 47 is formed on the second connection portion C2 side of the second split piece 42B.

Reinforcing ribs 54 protrude from the first connecting portion C1 to the second connecting portion C2 so as to extend in the circumferential direction of the pipe 1 on the outer surfaces of the first divided piece 42A and the second divided piece 42B. . The number of ribs 54 for reinforcement is not particularly limited and is arbitrary, but it is preferable that there be a plurality of ribs.

The pressure fixing ring 41 of the modified example configured in this way is attached to the case 20 as follows. First, the first split piece 42A and the second split piece 42B are separated and arranged so that the inner surfaces on which the pressing surfaces 44 are formed face each other (see FIG. 8). At that time, the pipe 1 to which the rectangular rubber block 2 is previously fitted is arranged between the first split piece 42A and the second split piece 42B. At this time, one end surface of the square rubber block 2 is brought into contact with the flange portion 25 provided on the case 20 side. Further, the outer peripheral surface 2a of the square rubber block 2 is arranged so as to correspond to the position where the pressing surface 44 on the side of the first split piece 42A and the pressing surface 44 on the side of the second split piece 42B are located. In addition, the vertex portion 2b of the square rubber block 2 is made to correspond to the position of the intersection of the pressing surfaces 44 on the first split piece 42A side and the intersection of the pressing surfaces 44 on the second split piece 42B side. Deploy.

Then, the engaging claws 53 projecting from the second split piece 42B are engaged with the engaging holes 52 provided in the first split piece 42A, and the fastening members 57 such as bolts are inserted into both bolt insertion holes 47. Insert and tighten (see Figure 9). As a result, the first split piece 42A and the second split piece 42B are connected to each other, and the square rubber block 2 arranged therebetween is sandwiched and pressed by both members. Then, as a result of holding force acting on the outer peripheral surface of the pipe 1 via the square rubber block 2 which is in close contact with the pipe 1 , the pipe 1 is held and fixed to the case 20 . The square rubber block 2 has a square outer shape when viewed from the axial direction of the pipe 1 . The pressing and fixing ring 41 of the modified example presses the outer peripheral surface 2a including the vertex portion 2b of such a square-shaped square rubber block 2 toward the center. Therefore, the pressing force from the pressing fixing ring 41 of the modified example efficiently acts on the square rubber block 2 to compress the square rubber block 2 . This compression action firmly holds and fixes the pipe 1 to the case 20 with a sufficient holding force. Specifically, in this modification, sufficient holding force is obtained to the extent that the pipe 1 is not displaced even when pushed in the axial direction with a force of 10 kgf.

Therefore, according to this embodiment, the following effects can be obtained.

(1) According to the straight type flowmeter sensor 11 of the present embodiment, the pressing force from the press fixing ring 41 efficiently acts on the square rubber block 2 to compress the square rubber block 2 as described above. That is, the diameter of the center hole 3 of the square rubber block 2 is reduced. This compression action firmly holds and fixes the pipe 1 to the case 20 with a sufficient holding force. Therefore, it is possible to prevent the pipe 1 from being displaced in the axial direction, and it is also possible to prevent a gap from forming between the case 20 and the pipe 1 and to prevent water or the like from entering therethrough. Therefore, waterproofness is improved. In addition, since the wetted part is formed of a straight tube made of fluororesin such as PFA, it is excellent in chemical resistance and heat resistance.

(2) In the straight type flowmeter sensor 11 of this embodiment, the square rubber block 2 is fitted onto the outer case region R1 of the pipe 1, and the press fixing ring 41 is attached there. With this configuration, the square rubber block 2 does not need to be built in the case 20, so the case 20 itself can be made smaller.

(3) In the straight type flowmeter sensor 11 of the present embodiment, the flange portions 25 are formed as projections on the end faces 21a and 21b of the case 20, and the square rubber block 2 and the flange portions 25 are sandwiched between the pressing and fixing rings 41. there is Therefore, the pipe 1 is held and fixed to the case 20 more firmly.

(4) In the straight type flowmeter sensor 11 of the present embodiment, the press fixing ring 41 is provided separately from the case 20, so that it can be manufactured through processes different from those for the case 20. FIG. For this reason, there is an advantage in that it is easier to form a complicated shape suitable for pressing compared to, for example, one formed integrally with the case 20 (see the modified examples shown in FIGS. 4 to 9). Moreover, the pressing force for holding and fixing the square rubber block 2 does not have to depend on the case 20 . In other words, it becomes unnecessary to use part of the screw tightening force when fixing the lid portion 28 to the case body 21 using the fastening member as the pressing force. Therefore, for example, even when a high-temperature liquid is flowed through the pipe 1, the case 20 is less likely to be thermally deformed, and the risk of lowering the pressing force resulting therefrom is eliminated.

(5) In the straight type flow meter sensor 11 of the present embodiment, a square rubber block 2 having a square shape in front view and having four vertex portions 2b is used as an elastic member. Therefore, compared to a polygonal rubber block having an odd number of vertex portions 2b, for example, the elastic member itself and the press fixing ring 41 having a corresponding shape can be formed more easily. Moreover, since the pressing force can be applied toward the center of the elastic member from two diagonal directions, the pressing force can be applied effectively to the pipe 1 and the like.

(6) The pressing fixing ring 41 in the straight type flowmeter sensor 11 of the present embodiment is formed into a substantially annular shape by combining a pair of split pieces 42 having the same shape, or a first split piece 42A and a second split piece 42B. It is configured. In particular, in the pressing and fixing ring 41 of the modified example, the second split piece 42B is provided with the engaging claw 53, and the first split piece 42A is provided in the engaging hole 52. to engage. Then, the first split piece 42A and the second split piece 42B are connected to each other using a fastening member. Therefore, by tightening the fastening member while the square rubber block 2 is arranged in the press fixing ring 41 , the pressing force can be efficiently and reliably applied toward the center of the square rubber block 2 . Further, since the reinforcing ribs 54 extending in the circumferential direction of the pipe 1 protrude from the outer surface of the pressing and fixing ring 41, the pressing and fixing ring 41 is reinforced. As a result, even if the square rubber block 2 is strongly tightened, the pressing fixing ring 41 is less likely to deform. Therefore, it is possible to reliably press the square rubber block 2 with a sufficient pressing force, thereby more reliably preventing displacement of the pipe 1 in the axial direction.

(7) The pressing fixing ring 41 in the straight type flowmeter sensor 11 of the present embodiment has a substantially annular shape, and the inner surface has four pressing surfaces that contact the vertex portion 2b and the outer peripheral surface 2a of the square rubber block 2. 44. Therefore, the four pressing surfaces 44 contact the four vertex portions 2b and the outer peripheral surface 2a of the square rubber block 2, respectively. Due to this contact, the outer peripheral surface 2a including the vertex portion 2b of the square rubber block 2 is efficiently and reliably pressed toward the center of the elastic member. Also, the pressing and fixing ring 41 includes the square rubber block 2 . That is, the first wall portion 43 contacts and covers one end surface of the square rubber block 2 , and the second wall portion 46 contacts and covers the other end surface of the square rubber block 2 . As a result, deformation of the rectangular rubber block 2 in the direction of both end faces when pressed by the pressing fixing ring 41 is suppressed. As a result, the loss of the pressing force is reduced, and the pressing force can be efficiently applied toward the center of the square rubber block 2 .

[Second embodiment]

The straight type flowmeter sensor 11A of the second embodiment will be described in detail below with reference to FIGS. 10 and 11. FIG. FIG. 10 is an exploded perspective view showing this straight type flow meter sensor 11A, and FIG. 11 is an exploded longitudinal sectional view of the same. Here, common member numbers are given to the same configurations as in the first embodiment, and detailed descriptions thereof are omitted.

A straight type flowmeter sensor 11A of this embodiment includes a case 20, a square rubber block 2 as an elastic member, a pressing fixing ring 41 as a pressing fixing member, and the like. In addition, a transducer housing box, a pair of ultrasonic transducers, and a sensor module assembled by a pair of shoes are attached to predetermined locations in the case inner region R2 of the pipe 1, but the illustration is omitted here. there is

In this straight-type flowmeter sensor 11A, square rubber blocks 2 are fitted on the pipe 1 at two spaced apart locations in the case inner region R2. This point is different from the first embodiment. The press fixing ring 41 is composed of a pair of divided pieces 42C having the same shape. Two substantially V-shaped pressing surfaces 44 are formed on the inner side surfaces of these split pieces 42C. The split piece 42</b>C has a first wall portion 74 and a second wall portion 72 on both sides of the pressing surface 44 . A pipe insertion portion 73 is provided on the outer surface of the first wall portion 72 , and a flange portion 71 as a projection is formed at the tip of the pipe insertion portion 73 . In other words, the present embodiment differs from the first embodiment in that the flange portion 71 is integrally formed on the press fixing ring 41 side instead of on the case 20 side.

Further, the case 20 in this straight type flowmeter sensor 11A is composed of an upper case member 61 and a lower case member 62 having the same structure. The upper case member 61 has end faces 61a and 61b on both sides thereof. The central portions of the end faces 61a and 61b are notched in a semicircular shape, and a concave portion 64 forming a part of the pipe insertion hole is formed there. A flange holding groove 63 is formed outside the recess 64 . The concave portion 64 is narrower than the portion of the flange portion holding groove 63 . Pressing recesses 65 are formed on the inner surface of the upper case member 61 near the

respective end surfaces

61a and 61b so as to contact the outer peripheral surface of the pressing fixing ring 41 and apply a pressing force. The inner surface of this pressing recess 65 is an arc-shaped concave surface. The lower case member 62 has end faces 62a and 62b on both sides thereof. The lower case member 62 also has the same configuration as the upper case member 61 (recess 64, flange holding groove 63, pressing recess 65).

This straight type flowmeter sensor 11A is assembled in the following procedure. First, the square rubber blocks 2 are fitted on the outside of the piping 1 at two spaced apart locations in the case inner region R2. Next, each square rubber block 2 is vertically sandwiched between a pair of split pieces 42C. Further, this is arranged between the upper case member 61 and the lower case member 62 and sandwiched between them. At this time, the outer peripheral surface of one split piece 42C contacts the pressing recess 65 of the upper case member 61, and the outer peripheral surface of the other split piece 42C contacts the pressing recess 65 of the lower case member 62. As shown in FIG. Moreover, the flange portions 71 of these split pieces 42C are arranged so as to engage with the flange portion holding grooves 63 . Then, the upper case member 61 and the lower case member 62 are fastened and fixed to each other using a fastening member (not shown).

In the case of the straight type flowmeter sensor 11A configured as described above, the tightening force for fixing the upper case member 61 and the lower case member 62 acts as a force for closing the pair of split pieces 42C via the pressing recess 65. do. As a result, the square rubber block 2 arranged between the pair of split pieces 42C is sandwiched and pressed by both members. Therefore, it is possible to obtain the straight type flowmeter sensor 11A which is excellent in chemical resistance and heat resistance, and excellent in holding force of the pipe 1 with respect to the case 20, which can reliably prevent displacement of the pipe 1 in the axial direction. . Also, with this configuration, the square rubber block 2 and the split piece 42C are accommodated in the case 20 and are not visible from the outside. Therefore, it is possible to achieve a neat design as a whole with a small number of protruding parts. A flange portion 71 projecting from the outer surface of the press fixing ring 41 is also sandwiched between the upper case member 61 and the lower case member 62 that constitute the case 20 . Therefore, the pipe 1 is held and fixed to the case 20 more firmly.

[Third embodiment]

The straight type flowmeter sensor 11B of the third embodiment will be described in detail below with reference to FIGS. 12 and 13. FIG. FIG. 12 is an exploded perspective view showing this straight type flowmeter sensor 11B, and FIG. 13 is an exploded cross-sectional view of the same. Here, the same member numbers are assigned to the same configurations as in the first and second embodiments, and detailed descriptions thereof are omitted.

The straight flowmeter sensor 11B of this embodiment includes a case 20 (an upper case member 61 and a lower case member 62), a square rubber block 2 as an elastic member, a press fixing member 81, and the like. In addition, a transducer housing box, a pair of ultrasonic transducers, and a sensor module assembled by a pair of shoes are attached to predetermined locations in the case inner region R2 of the pipe 1, but the illustration is omitted here. there is

This straight type flowmeter sensor 11B differs from that of the second embodiment in that the structures of the upper case member 61 and the lower case member 62 are not the same. The upper case member 61 has end faces 61a and 61b on both sides thereof. The central portions of the end faces 61a and 61b are notched in a semicircular shape, and a concave portion 77 forming a part of the pipe insertion hole is formed there. The lower case member 62 has end faces 62a and 62b on both sides thereof. The central portions of the end surfaces 62a and 62b are notched in a semicircular shape, and recesses 77 forming part of the pipe insertion holes are formed there. However, a pressure fixing portion 78 as a pressure fixing member is integrally formed on the inner surface side of the lower case member 62 . In other words, the straight type flowmeter sensor 11B of this embodiment includes a pressing fixing member formed separately from the case 20 and a pressing fixing member integrally formed with the case 20. . These pressing fixing portions 78 are arranged at both ends of the lower case member 62, and recesses 77, pressing surfaces 44, and recesses 79 are formed there. Bolt insertion holes 75 are formed on both sides of the pressing surface 44 .

The press fixing member 81 of this embodiment, which is formed separately from the case 20, has a shape similar to the split piece 42C shown in the second embodiment, and has a substantially V-shaped inner surface. Two pressing surfaces 44 are formed. The split piece 42C has a pair of plate-like portions 83, and bolt insertion holes 84 are formed in the plate-like portions 83, respectively.

This straight type flow meter sensor 11B is assembled in the following procedure. First, the square rubber blocks 2 are fitted on the outside of the piping 1 at two spaced apart locations in the case inner region R2. Next, each square rubber block 2 is set so as to be fitted into the press fixing portion 78 of the lower case member 62 . In this state, the square rubber block 2 is covered with the press fixing member 81, and the bolts are inserted through the bolt insertion holes 75 and 84 and tightened. As a result, the square rubber block 2 is sandwiched and fixed from above and below. Thereafter, the upper case member 61 is covered with the lower case member 62 and fixed to each other.

Even the straight type flowmeter sensor 11B having the above configuration is excellent in chemical resistance and heat resistance, and is excellent in holding force of the pipe 1 with respect to the case 20, thereby surely preventing displacement of the pipe 1 in the axial direction. It is possible to obtain a straight type flow meter sensor 11B that can In addition, since the press fixing portion 78 is formed integrally with a part of the case 20, the number of parts can be reduced compared to the case 20 formed separately. Also, it is possible to reduce the number of assembly man-hours.

[Fourth embodiment]

The straight type flowmeter sensor 11C of the fourth embodiment will be described in detail below with reference to FIGS. 14 and 15. FIG. FIG. 14 is an exploded perspective view showing this straight type flowmeter sensor 11C, and FIG. 15 is an exploded cross-sectional view of the same. Here, the same member numbers are assigned to the same configurations as those of the first to third embodiments, and detailed descriptions thereof are omitted.

A straight flowmeter sensor 11C of this embodiment includes a case 20 (an upper case member 61 and a lower case member 62) and a square rubber block 2 as an elastic member. Further, the straight type flow meter sensor 11C is different from that of the third embodiment in that it does not have a pressure fixing member 81 formed separately, but only a pressure fixing portion 78. there is In addition, a transducer housing box, a pair of ultrasonic transducers, and a sensor module assembled by a pair of shoes are attached to predetermined locations in the case inner region R2 of the pipe 1, but the illustration is omitted here. there is

A lower case member 62 constituting the case 20 of this embodiment has basically the same structure as the lower case member 62 of the third embodiment, except that the bolt insertion holes 75 are not provided. Also, the upper case member 61 has the same structure as the lower case member 62 . That is, the press fixing portion 78 is integrally formed with the upper case member 61 and the lower case member 62 of the present embodiment.

This straight type flow meter sensor 11C is assembled in the following procedure. First, the square rubber blocks 2 are fitted on the outside of the piping 1 at two spaced apart locations in the case inner region R2. Next, each square rubber block 2 is set so as to be fitted into the press fixing portion 78 of the lower case member 62 and the upper case member 61, respectively. In this state, the lower case member 62 and the upper case member 61 are fastened and fixed with a fastening member. As a result, the square rubber block 2 is sandwiched and fixed from above and below.

Even the straight type flowmeter sensor 11C having the above configuration is excellent in chemical resistance and heat resistance, and is excellent in holding force of the pipe 1 with respect to the case 20, thereby surely preventing displacement of the pipe 1 in the axial direction. A straight type flowmeter sensor 11C can be obtained. In addition, since the press fixing portion 78 is formed integrally with a part of the case 20, the number of parts can be reduced compared to the case 20 formed separately. Also, it is possible to reduce the number of assembly man-hours.

It should be noted that the embodiment of the present invention may be modified as follows.

- In the above-described embodiment, the square rubber block 2 having a square shape in a front view is used as the elastic member, but the present invention is not limited to this. For example, a hexagonal rubber block or an octagonal rubber block may be used as a polygonal shape having an even number of vertex portions 2b.

FIGS. 16(a) to (d) exemplify a pressing fixing member 41 of another embodiment. The pressing fixing member 41 of FIG. 16(a) is constructed by combining a pair of split pieces 42D. An elastic member holding concave portion 40 is formed on the joint surface between the pair of split pieces 42D. The elastic member holding recess 40 is for holding the square rubber block 2, which is an elastic member, and has a rectangular cross section. The elastic member holding recess 40 is composed of three pressing surfaces 44 that contact the vertex portion 2b and the outer peripheral surface 2a of the square rubber block 2. As shown in FIG. Of the three pressing surfaces 44, the two pressing surfaces 44 connected to the opening edge of the elastic member holding recess 40 are not inclined to face the joint surface side, but are perpendicular to the joint surface. Therefore, when using a square rubber block 2 slightly larger than the elastic member holding recess 40 , it becomes difficult to dispose the square rubber block 2 in the elastic member holding recess 40 .

On the other hand, in the press fixing member 41 shown in FIG. 16(b), the elastic member holding recess 40 formed in the joint surface between the pair of split pieces 42E is for holding the square rubber block 2 and has an isosceles triangular cross section. It has a shape. The elastic member holding recess 40 is composed of two pressing surfaces 44 that contact the vertex portion 2b and the outer peripheral surface 2a of the square rubber block 2. As shown in FIG. These two pressing surfaces 44 are connected to the opening edge of the elastic member holding recess 40 and are inclined at 45° so as to face the joint surface side. Therefore, even when the square rubber block 2 having a size slightly larger than the elastic member holding recess 40 is used, the square rubber block 2 can be easily arranged in the elastic member holding recess 40 . Further, the outer peripheral surface 2a including the vertex portion 2b of the square rubber block 2 is efficiently and reliably pressed toward the center of the elastic member, and the pressing force acts effectively. Note that when a pair of split pieces 42E is used, mainly the vertex portion 2b of the square rubber block 2 is pressed toward the center of the square rubber block 2. As shown in FIG.

16(c) is configured by combining a pair of split pieces 42F. An elastic member holding recess 40 is formed in the joint surface between the pair of split pieces 42F. The elastic member holding recess 40 is for holding a hexagonal rubber block 92, which is an elastic member, and has a pentagonal shape. The elastic member holding recess 40 is composed of three pressing surfaces 44 that contact the vertex portion 2b and the outer peripheral surface 2a of the hexagonal rubber block 92. As shown in FIG. Of the four pressing surfaces 44, two pressing surfaces 44 connected to the opening edge of the elastic member holding recess 40 are not inclined to face the joint surface side, but are perpendicular to the joint surface. Therefore, when the hexagonal rubber block 92 having a size slightly larger than the elastic member holding recess 40 is used, it becomes difficult to dispose the hexagonal rubber block 92 inside the elastic member holding recess 40 .

On the other hand, in the press fixing member 41 shown in FIG. 16(d), the elastic member holding recess 40 formed in the joint surface between the pair of split pieces 42G is for holding the hexagonal rubber block 92 and has a trapezoidal cross section. presenting. The elastic member holding recess 40 is composed of three pressing surfaces 44 that contact the vertex portion 2b and the outer peripheral surface 2a of the hexagonal rubber block 92. As shown in FIG. Two of these three pressing surfaces 44 are connected to the opening edge of the elastic member holding recess 40 and are inclined by 30° so as to face the joint surface side. Therefore, even when the hexagonal rubber block 92 having a size slightly larger than the elastic member holding recess 40 is used, the hexagonal rubber block 92 can be easily arranged in the elastic member holding recess 40 . Further, the outer peripheral surface 2a including the apex portion 2b of the hexagonal rubber block 92 is efficiently and reliably pressed toward the center of the elastic member, and the pressing force acts effectively. Note that when a pair of split pieces 42G is used, mainly the outer peripheral surface 2a of the hexagonal rubber block 92 is pressed toward the center of the hexagonal rubber block 92. As shown in FIG.

- In the above-described embodiment, the pressing and fixing ring 41 is configured in a substantially annular shape by combining the two split pieces 42, but the configuration is not limited to this. For example, the pressing and fixing ring 41 having a substantially annular shape may be configured by combining three split pieces 42 .

1... Piping

2 ... Square rubber block as an elastic member

2a: outer peripheral surface of the elastic member

2b... vertex portion of the elastic member

11, 11A, 11B, 11C...Straight type flowmeter sensor

20... Case

21a, 21b... end faces of the case

25, 71... Flanges as projections

33... Ultrasonic vibrator

40... Elastic member holding recessed part

41: pressing and fixing ring as a pressing and fixing member

42, 42C, 42D, 42E, 42F, 42G, ... segmented pieces

42A... First split piece

42B... second split piece

44... Pressing surface

52... Engagement hole

53... Engagement pawl

54 ... Rib for reinforcement

57 ... bolt as a fastening member

81: Pressing and fixing portion as a pressing and fixing member

C1... 1st connecting part

C2... second connection part

R1: area outside the case

R2: region inside the case

Claims

a pair of ultrasonic transducers arranged offset in the axial direction of a straight fluororesin pipe through which a fluid flows and capable of transmitting and receiving ultrasonic waves;

a case that accommodates and positions and fixes the pair of ultrasonic transducers;

A straight flow meter sensor comprising:

an elastic member that is fitted onto the pipe and has a polygonal outer shape when viewed from the axial direction of the pipe;

a press fixing member that fixes the pipe to the case by sandwiching the elastic member and pressing the outer peripheral surface including the apex portion of the elastic member toward the center of the elastic member;

A straight flowmeter sensor, comprising:
2. The straight type flow meter sensor according to claim 1, wherein the elastic member is fitted on the outside of the case of the pipe.
3. The straight type flowmeter sensor according to claim 2, wherein a projection is formed on the end surface of said case, and said elastic member and said projection are sandwiched between said pressing and fixing member.
2. The straight type flowmeter sensor according to claim 1, wherein the elastic member is fitted on the inside of the case of the pipe.
5. The straight type flow meter sensor according to claim 2, wherein a protrusion is formed on the outer side surface of said pressing and fixing member, and said protrusion is sandwiched between said cases.
6. The straight type flow meter sensor according to claim 1, wherein said pressing fixing member is provided separately from said case.
5. The straight type flow meter sensor according to claim 1, wherein said pressing fixing member is formed integrally with a part of said case.
8. The straight type flowmeter sensor according to claim 1, wherein said elastic member has a polygonal shape with an even number of said vertex portions.
The elastic member has a rectangular or hexagonal outer shape when viewed from the axial direction of the pipe,

The pressing and fixing member is configured by combining a pair of split pieces, and the joint surface between the pair of split pieces is an elastic member comprising a plurality of pressing surfaces that come into contact with the apex portion and the outer peripheral surface of the elastic member. A member holding recess is formed, and among the plurality of pressing surfaces, one connected to an opening edge of the elastic member holding recess is inclined so as to face the joint surface,

When the elastic member is sandwiched between the pair of split pieces, the center of the pipe is positioned on the extension of the joint surface.

The straight type flowmeter sensor according to any one of claims 1 to 8, characterized in that:
6. The straight type flowmeter sensor according to claim 3, wherein the protrusion is a flange portion projecting from the end surface of the case or the outer surface of the pressing and fixing member so as to surround the pipe. .
The pressing and fixing member is a pressing and fixing ring configured in a substantially annular shape by combining a pair of split pieces,

The pair of split pieces each have a first connection portion and a second connection portion at both ends,

In the first connecting portion, an engaging claw projecting from one of the split pieces is engaged with an engaging hole provided in the other split piece, and at the second connecting portion, one of the split pieces The pair of split pieces are connected to each other by screwing the fastening member through which the split piece is inserted into the other split piece.

10. The straight type flow meter sensor according to claim 9, characterized in that:
12. The straight type flowmeter sensor according to claim 1, wherein reinforcing ribs extending in the circumferential direction of the pipe are protruded from the outer surface of the pressing and fixing member.
13. The straight type flowmeter sensor according to any one of claims 1 to 12, wherein the pressing and fixing member includes the elastic member.