JP2008002879A - Ultrasonic sensor mounting member for flow meter - Google Patents

Abstract

An object of the present invention is to provide a sensor mounting member capable of preventing occurrence of a short circuit in a terminal pin portion of an ultrasonic sensor of an ultrasonic flow meter.
A terminal pin 7c, 7c of an ultrasonic sensor 7 is fitted on an outer periphery of the other end surface 7b of the ultrasonic sensor 7 on an attachment member 5 used for attaching the ultrasonic sensor 7 to an intermediate flow path of a gas meter. A presser portion 5c that presses against and seals the end surface and outer peripheral surface of the seal member 9 to the end surface and inner peripheral surface of the step portion 1m of the mounting opening 1k, and a terminal pin penetrating the presser portion 5c. In the installed state of the gas meter 1 projecting from the open hole 5d for exposing 7c, 7c, the partition piece 5e extending from the holding portion 5c and interposed between the terminal pins 7c, 7c, and the upper mounting piece portion 5a A shielding piece 5f is provided above each terminal pin 7c, 7c to cover them.
[Selection] Figure 3

Description

  The present invention relates to a member used for mounting an ultrasonic sensor in an ultrasonic flow meter that measures a flow rate of gas or the like using an ultrasonic sensor.

  As one of the electronic gas meters that measure the gas flow rate using a microcomputer, a pair of ultrasonic sensors facing each other are displaced in the gas flow direction in the flow path and intersect with the gas flow direction. There is an ultrasonic gas meter that is arranged at intervals in the width direction of the flow path and calculates the flow rate or flow rate of the gas flowing through the flow path by a microcomputer from the difference in ultrasonic transmission speed between the pair of ultrasonic sensors. is there.

In this ultrasonic gas meter, in order to eliminate the influence of gravity on the gas flow velocity, the measurement of the gas flow velocity or flow rate by the ultrasonic sensor is performed at the bottom of the gas meter casing that extends horizontally in the installed state of the gas meter. While being performed in the flow channel part, by attaching each ultrasonic sensor to the openings formed on the side walls on both sides in the horizontal width direction of the flow channel part, exposing the transmitting and receiving surfaces inside the flow channel part, Both ultrasonic sensors are positioned in the same horizontal plane with the gas meter installed (for example, Patent Documents 1 and 2).
JP 2005-257444 A JP 2006-17499 A

  Incidentally, some of the above-described ultrasonic sensors have a substantially cylindrical shape, and when such an ultrasonic sensor is attached to the flow channel portion, one end surface side that is a transmission / reception surface is an opening on the side wall of the flow channel portion. In general, the flange is inserted into the flow path portion from the portion, and a flange extending in the radial direction from the circumferential surface of the ultrasonic sensor is applied to the side wall portion of the flow path portion at the periphery of the opening portion and screwed.

  Thus, when performing the work of attaching the ultrasonic sensor to the flow path part, since a pair of terminal pins for signal input and output projecting on the other end face is often pinched with fingers, Depending on the force applied at that time, the terminal pins are bent, and there is a risk that the terminal pins will contact each other and be short-circuited only by a slight vibration after the gas meter is installed.

  Also, since the gas meter is often installed outdoors, the surface of the flow channel etc. accommodated inside the gas meter is cooled by a decrease in the outside air temperature etc. Condensation may occur in the gas meter, or rainwater that has entered the inside of the gas meter may adhere to the surface of the flow path, etc., and the condensed water or rainwater will drop on the terminal pin of the ultrasonic sensor through the flange. There is a risk that the terminal pins are electrically connected via dew condensation water and short-circuited.

  If the terminal pins are electrically connected to each other, whether directly or indirectly, a short circuit may occur, causing damage or failure of the ultrasonic sensor and its surrounding electrical elements. This is not preferable because it hinders the performance.

  Further, such a problem is not limited to the ultrasonic gas meter described above. For example, the flow rate of a fluid containing liquid (pure water, ultrapure water, chemical liquid, highly corrosive liquid, etc.), etc. This is widely applied to all types of flowmeters that measure using the.

  The present invention has been made in view of the above circumstances, and an object of the present invention is an ultrasonic flow meter that measures the flow rate of a fluid such as gas or liquid using an ultrasonic sensor, in a terminal pin portion of the ultrasonic sensor. An object of the present invention is to provide a sensor mounting member capable of preventing occurrence of a short circuit.

  In order to achieve the object, the ultrasonic sensor mounting member for a flow meter according to the present invention described in claim 1 is dropped from the outside of the flow channel of the flow meter to the opening for mounting the flow channel to the inside of the flow channel. The ultrasonic sensor inserted in the retaining state in which the protrusion is prevented is inserted into the flow path with the protruding surfaces of the pair of signal input / output terminal pins of the ultrasonic sensor exposed to the outside of the flow path. An attachment member used for attachment, wherein the attachment piece is attached to a flow passage portion at a peripheral edge of the attachment opening in the flow passage, and the attachment piece portion is attached to the flow passage portion. A state where the ultrasonic sensor inserted into the opening for preventing the ultrasonic sensor is pressed against the peripheral edge of the projecting surface, and a state where the attachment piece is attached to the flow path portion. And inserted into the mounting opening in a retaining state. An opening hole for exposing the pair of terminal pins of the acoustic wave sensor, and extending from the pressing portion into the opening hole, and the attachment piece portion being attached to the flow path portion, the attachment opening. And a partitioning piece made of an insulating material interposed between the pair of terminal pins of the ultrasonic sensor inserted in a retaining state.

  The ultrasonic sensor mounting member for a flow meter according to the present invention described in claim 2 is provided so as to protrude from the mounting piece in the ultrasonic sensor mounting member for a flow meter according to the present invention described in claim 1, A cover made of an insulating material extending from the tip of each terminal pin to a location spaced in the projecting direction of the terminal pin and covering the tip of each terminal pin; and the cover and the partition piece Are connected to each other.

  Furthermore, the ultrasonic sensor mounting member for a flow meter according to the present invention described in claim 3 is prevented from dropping into the flow channel from the outside of the flow channel to the mounting opening of the flow channel. The ultrasonic sensor inserted in the retaining state is used to attach the ultrasonic sensor to the flow path with the protruding surfaces of the pair of signal input / output terminal pins exposed to the outside of the flow path. An attachment member, wherein the attachment piece is attached to a flow passage portion at the periphery of the attachment opening in the flow passage, and the attachment piece portion is attached to the flow passage portion. A pressing part that presses against a peripheral edge of the projecting surface of the ultrasonic sensor that is inserted in a stopped state, and a penetrating through the pressing part. Of the ultrasonic sensor inserted in the opening for preventing An open hole for exposing the pair of terminal pins, and the terminal pin of the liquid that protrudes from the mounting piece along the pair of terminal pins and is dropped from above the terminal pins in the installed state of the flow meter And a shielding piece for preventing adhesion to the surface.

  According to the ultrasonic sensor mounting member for a flow meter of the present invention described in claim 1, the mounting piece is mounted on the flow path portion at the periphery of the mounting opening, and is inserted into the mounting opening in a retaining state. A partition made of an insulating material that extends from the presser part toward the open hole that exposes the pair of terminal pins that protrude from the projecting surface when the presser part is pressed against the peripheral edge of the projecting surface of the acoustic wave sensor A piece is interposed between the pair of terminal pins.

  For this reason, even when the ultrasonic sensor is inserted into the mounting opening, even if the pair of terminal pins is bent by being pinched with fingers, the direct or indirect electrical connection between the pair of terminal pins can be separated. Therefore, the occurrence of a short circuit can be surely prevented.

  Further, according to the ultrasonic sensor mounting member for a flow meter of the present invention described in claim 2, the ultrasonic sensor mounting member for a flow meter of the present invention described in claim 1 is provided so as to protrude from the mounting piece. Since the cover and the partition piece extending from the tip of each terminal pin to the location spaced in the projecting direction are connected, the terminal pin can be protected from mechanical damage such as breakage by the cover. In addition, the strength of the partition piece can be increased as compared with the case where it is connected only to the presser piece, and the strength of the cover itself can be increased as compared to the case where it is connected only to the attachment piece portion.

  Furthermore, according to the ultrasonic sensor mounting member for a flow meter of the present invention as set forth in claim 3, the mounting piece is mounted on the flow path portion around the mounting opening in the installation state of the flow meter, and the mounting opening When the presser part is pressed against the peripheral edge of the protruding surface of the ultrasonic sensor inserted in a state where it is prevented from coming off, it is dropped from above the terminal pin by the shielding piece protruding from the mounting piece along the terminal pin. Liquid is prevented from adhering to the terminal pins.

  For this reason, the shielding piece prevents the liquid from dropping and adhering to the terminal pins that would cause the pair of terminal pins to be electrically connected to each other. Can be prevented.

  Hereinafter, embodiments of an ultrasonic sensor mounting member for a flow meter of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a gas meter to which the present invention is applied. A gas meter (corresponding to a flow meter in the claims) shown in FIG. 1 is cut off by a shutoff valve 3 from a gas inlet 1a. A gas meter 1 is connected to the inflow side channel 1c and the outflow side channel 1d by connecting the inflow side channel 1c and the outflow side channel 1d with respect to the flow rate of the gas flowing in through the valve port 1b and the inflow side channel 1c and flowing out through the outflow side channel 1d. In the intermediate flow path 1f (corresponding to the flow path in the claims) extending horizontally in the installed state.

  As shown in the plan view of FIG. 2, the intermediate flow path 1f has an inflow port 1g connected to the inflow side flow path 1c and an outflow port 1h connected to the outflow side flow path 1d. An attachment member made of an insulating material such as plastic according to an embodiment of the present invention is provided at a position near the inlet 1g of the one side wall 1i of the flow path 1f and a position near the outlet 1h of the other side wall 1j (in claims) The ultrasonic sensors 7 are respectively attached to the flow meter ultrasonic sensor attaching member 5).

  FIG. 3 is an enlarged cross-sectional view of a main part showing a mounting portion of the ultrasonic sensor 7, and the ultrasonic sensor 7 having a substantially cylindrical shape is formed on the side walls 1i and 1j of the intermediate flow path 1f to which the ultrasonic sensor 7 is mounted. A mounting opening 1k having a slightly larger diameter is provided so as to communicate between the inside and the outside of the intermediate flow path 1f. The mounting opening 1k near the outer surface of the side walls 1i, 1j A step portion 1m for preventing the ultrasonic sensor 7 from dropping out into the flow path 1f is formed.

  The ultrasonic sensor 7 has one end surface 7a on which an ultrasonic transmission / reception unit is disposed and a pair of terminal pins 7c and 7c for signal input / output (only one terminal pin 7c is shown in FIG. 3). The other end surface 7b (corresponding to the projecting surface in the claims) is provided, and one end surface 7a side is formed with an outer diameter smaller than the inner diameter of the mounting opening 1k, The end face 7b side is formed with an outer diameter smaller than the inner diameter of the stepped portion 1m and larger than the one end face 7a.

  An annular seal member 9 is fitted on the outer periphery of the ultrasonic sensor 7 on the other end surface 7 b side, and the peripheral surface of the ultrasonic sensor 7 on the one end surface 7 a side is from the seal member 9. It is covered with a thin cylindrical portion 9a extending integrally.

  When the seal member 9 is fitted to the outer periphery on the other end surface 7b side, the one end surface 7a side of the ultrasonic sensor 7 is attached to the mounting opening so that the one end surface 7a is exposed inside the intermediate flow path 1f. 1k, the end surface and the outer peripheral surface of the seal member 9 come into contact with the end surface and the inner peripheral surface of the stepped portion 1m, respectively, and the outer peripheral surface of the cylindrical portion 9a is slightly spaced from the inner peripheral surface of the mounting opening 1k. It is comprised so that it may be arranged.

  Each of the mounting members 5 has upper and lower flange portions 1n, 1p formed on the side walls located at the upper and lower peripheral edges of the mounting opening 1k in the installed state of the gas meter 1 among the side walls 1i, 1j of the intermediate flow path 1f. The upper and lower mounting pieces 5a and 5b are screwed to (corresponding to the flow path portion at the periphery of the mounting opening in the claims).

  Further, as shown in the enlarged perspective view as seen from the front side in FIG. 4, each mounting member 5 is provided with a presser portion 5c formed between the two mounting piece portions 5a and 5b, and the presser portion 5c. 5 d of open holes, the partition piece 5e extended toward the inside of the open hole 5d from the press part 5c, the shielding piece 5f projected from the peripheral part of the open hole 5d among the upper attachment piece parts 5a, 5b, and a cover 5g protruding from the peripheral edge of the opening hole 5d. As shown in the enlarged perspective view seen from the back side in FIG. It is connected with the partition piece 5e.

  As shown in FIG. 3, the mounting member 5 has one end face 7a side for mounting in a state where the upper and lower mounting pieces 5a and 5b are screwed to the upper and lower flange portions 1n and 1p of the intermediate flow path 1f. The pressing portion 5c is pressed against the seal member 9 fitted on the outer periphery of the other end surface 7b of the ultrasonic sensor 7 inserted into the opening 1k, and the end surface and the outer peripheral surface of the seal member 9 are connected to the step portion 1m of the mounting opening 1k. The end face and the inner peripheral surface are pressed against and brought into close contact with each other, and the open hole 5d penetrating the holding portion 5c exposes the pair of terminal pins 7c, 7c of the ultrasonic sensor 7, and between the pair of terminal pins 7c, 7c. Further, a partition piece 5e extending from the presser portion 5c is interposed.

  The attachment member 5 includes a shielding piece 5f protruding from the upper attachment piece 5a in a state where the upper and lower attachment pieces 5a and 5b are screwed to the upper and lower flange portions 1n and 1p of the intermediate flow path 1f. The gas meter 1 is installed above the terminal pins 7c, 7c so as to cover the terminal pins 7c, 7c, and project along the terminal pins 7c, 7c from the lower mounting piece 5b. A cover 5g extends to a portion on the extension line of each terminal pin 7c, 7c so as to cover the tip of each terminal pin 7c, 7c.

  Using the mounting member 5 having such a configuration, the terminal pins 7c and 7c of the ultrasonic sensor 7 inserted and mounted in the mounting openings 1k of the side walls 1i and 1j of the intermediate flow path 1f of the gas meter 1 The female connectors 11a and 11a of the transmission / reception lead wires 11 and 11 are fitted.

  As shown in the enlarged perspective view of the mounting member as viewed from the front side in FIG. 6, the lead wires 11 and 11 pass through the clip 5h projecting from the portion in the vicinity of the shielding piece 5f of the mounting member 5. It is wired to the microcomputer side (not shown) in the gas meter 1 that performs the measurement process.

  In the gas meter 1 of the present embodiment configured as described above, one end surface 7a side of the ultrasonic sensor 7 in which the seal member 9 is fitted to the outer periphery on the other end surface 7b side is used as the attachment opening 1k of the intermediate flow path 1f. When inserting, since it cannot have the other end surface 7b part and the sealing member 9 of the ultrasonic sensor 7 accommodated in the level | step-difference part 1m of the opening 1k for attachment, it often has the terminal pins 7c and 7c. The terminal pins 7c and 7c are bent depending on how the force is applied when the work is performed and the terminal pins 7c and 7c are held.

  However, if the mounting member 5 is used for mounting the ultrasonic sensor 7 to the mounting opening 1k of the intermediate flow path 1f as in the gas meter 1 of the present embodiment, the partition pieces 5e of the mounting member 5 made of an insulating material have both ends. Since these electrical connections are prevented by interposing between the child pins 7c and 7c, for example, even if a slight vibration is applied after the gas meter 1 is installed, the terminal pins 7c and 7c may come into contact with each other and short-circuit. There is no.

  Further, since the gas meter 1 is often installed outdoors, the inflow side in which the gas meter 1 into which the outside air has entered when the humidity is high is cooled by a decrease in the outside air temperature and is accommodated inside the gas meter 1. Condensation may occur on the surface of the flow path through which the gas in the gas meter 1 passes, such as the flow path 1c, the outflow side flow path 1d, and the intermediate flow path 1f.

  Moreover, since the gas meter 1 is installed outdoors, the intrusion into the rainwater does not always occur even though the gas meter 1 is sealed.

  However, like the gas meter 1 of this embodiment, if the attachment member 5 is used for attaching the ultrasonic sensor 7 to the attachment opening 1k of the intermediate flow path 1f, the shielding piece protruding from the upper attachment piece 5a. Since 5f is located above the connection portion between the terminal pins 7c and 7c of the ultrasonic sensor 7 and the female connectors 11a and 11a of the lead wires 11 and 11 when the gas meter 1 is installed, dew condensation water, infiltrated rainwater, etc. Even if it is dropped toward the connecting portion between the terminal pins 7c, 7c and the female connectors 11a, 11a along the surface of the mounting member 5, it is blocked by the shielding piece 5f and does not adhere to the terminal pins 7c, 7c. Therefore, there is no possibility that the terminal pins 7c and 7c are electrically connected via dew condensation water, infiltration rainwater, or the like and short-circuited.

  For this reason, the terminal pins 7c, 7c are directly mechanically contacted with each other due to the bending of the terminal pins 7c, 7c, etc., and the terminal pins 7c, 7c are in contact with each other through the condensed water or the infiltrated rain water in the gas meter 1. Due to the indirect electrical connection, it is possible to reliably prevent the ultrasonic sensor 7 and the microcomputer (not shown) from being broken and damaged due to a short circuit.

  In addition, any one of the partition piece 5e and the shielding piece 5f may be omitted, and when the partition piece 5e is provided, the cover 5g and the partition piece 5e are connected on the back side of the cover 5g. May be omitted.

  However, if the cover 5g and the partition piece 5e are connected as in this embodiment, the cover 5g is connected only to the holding part 5b, or the cover 5g is connected only to the lower attachment piece 5b. Since the strength of the cover 5g and the partition piece 5e can be increased compared with the structure to perform, it is advantageous.

  Furthermore, the cover 5g may be omitted regardless of whether the partition piece 5e and the shielding piece 5f are both provided or one of them is omitted. However, the cover 5g is provided as in the present embodiment. This is advantageous because the terminal pins 7c, 7c can be protected from mechanical damage such as breakage.

  In the above-described embodiment, the case where the present invention is applied to the ultrasonic gas meter 1 that measures the gas flow rate using the ultrasonic sensor 7 has been described as an example. Needless to say, the present invention is widely applicable to all flow meters that measure the flow rate of fluids including pure water, ultrapure water, chemicals, highly corrosive liquids, etc.) using an ultrasonic sensor.

It is sectional drawing of the gas meter to which this invention is applied. It is a top view of the intermediate flow path of FIG. It is a principal part expanded sectional view which shows the attachment part of the ultrasonic sensor in the intermediate | middle flow path of FIG. It is the expansion perspective view seen from the front side of the attachment member of FIG. It is the expansion perspective view seen from the back side of the attachment member of FIG. It is the expansion perspective view seen from the front side of the attachment member of FIG. 3 in the state which wired the lead wire.

Explanation of symbols

1 Gas meter (flow meter)
1f Intermediate flow path (flow path)
1k Mounting opening 1n, 1p Flange (flow path part around the mounting opening)
5a, 5b Mounting piece portion 5c Presser portion 5d Open hole 5e Partition piece 5f Shielding piece 5g Cover 7b End surface (projecting surface)

Claims (3)

An ultrasonic sensor inserted from the outside of the flow channel of the flow meter into the mounting opening of the flow channel in a state of being prevented from falling into the flow channel is connected to a pair of signal inputs of the ultrasonic sensor. An attachment member used to attach the projecting surface of the terminal pin for output to the flow path in a state exposed to the outside of the flow path,
An attachment piece attached to the flow passage portion at the periphery of the attachment opening in the flow passage;
With the attachment piece attached to the flow path portion, a pressing portion that presses against a peripheral edge of the projecting surface of the ultrasonic sensor inserted in the attachment opening in a retaining state, and
An opening hole that exposes the pair of terminal pins of the ultrasonic sensor that is inserted in the presser portion and is inserted in the attachment opening in a state of retaining the attachment piece portion attached to the flow path portion. When,
The pair of ultrasonic sensors that are extended from the presser portion into the open hole and are inserted into the attachment opening in a state of being prevented from being detached while the attachment piece portion is attached to the flow path portion. A partition made of insulating material interposed between the terminal pins;
An ultrasonic sensor mounting member for a flow meter, comprising:   A cover made of an insulating material projecting from the mounting piece and extending from the tip of each terminal pin to a location spaced in the projecting direction of the terminal pin to cover the tip of each terminal pin; The ultrasonic sensor mounting member for a flow meter according to claim 1, further comprising: the cover and the partition piece connected to each other. An ultrasonic sensor inserted from the outside of the flow channel of the flow meter into the mounting opening of the flow channel in a state of being prevented from falling into the flow channel is connected to a pair of signal inputs of the ultrasonic sensor. An attachment member used to attach the projecting surface of the terminal pin for output to the flow path in a state exposed to the outside of the flow path,
An attachment piece attached to the flow passage portion at the periphery of the attachment opening in the flow passage;
With the attachment piece attached to the flow path portion, a pressing portion that presses against a peripheral edge of the projecting surface of the ultrasonic sensor inserted in the attachment opening in a retaining state, and
An opening hole that exposes the pair of terminal pins of the ultrasonic sensor that is inserted in the presser portion and is inserted in the attachment opening in a state of retaining the attachment piece portion attached to the flow path portion. When,
A shielding piece that protrudes from the mounting piece along the pair of terminal pins and prevents the liquid dropped from above the terminal pins in the installed state of the flow meter from adhering to the terminal pins;
An ultrasonic sensor mounting member for a flow meter, comprising:

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