JP5510133B2 - Ultrasonic gas meter - Google Patents

Description

  The present invention relates to an ultrasonic gas meter that measures the flow rate of gas by propagating ultrasonic waves.

  Conventionally, this type of ultrasonic gas meter is provided with a gas inlet and outlet on the top surface of the gas meter so as to be suspended from a gas pipe. The inflow port and the outflow port are connected by a gas flow path member formed in a U-shaped cylinder provided inside the gas meter, and a measurement pipe for measuring the gas flow velocity is provided in the gas flow path member (for example, Patent Document 1).

  FIG. 4 shows a cross-sectional view of a conventional ultrasonic gas meter described in Patent Document 1. As shown in FIG. As shown in FIG. 4, the gas inlet 2 and outlet 3 provided on the top surface of the gas meter 1 formed in a rectangular box shape are connected by a gas flow path member 4 formed in a U-shaped cylindrical shape. It is a configuration. A measuring tube 6 for measuring the gas flow rate from the propagation time of ultrasonic waves is installed on the bottom surface portion 5 of the U-shaped channel. The measuring tube 6 is provided so that the ultrasonic wave propagation means 7a and 7b are opposed to the upstream side and the downstream side.

JP 2009-186430 A

  However, in the conventional configuration, water that has entered the gas flow path of the gas meter may accumulate on the bottom surface of the U-shaped gas flow path and the measurement pipe may be submerged. For example, in a gas meter for city gas, when the gas pipe and water pipe are installed adjacent to each other, when the water pipe corrodes and water leaks, the leaked water corrodes the gas pipe, Water may intrude into the gas meter, and as a result, water may enter the gas flow path of the gas meter.

  Even if water that has entered the gas flow path with sufficient capacity is stored, there is a limit depending on the amount of water that enters, and if the water storage capacity is increased, the gas meter becomes large and heavy. In an ultrasonic gas meter, the gas flow rate is measured based on the propagation time of the ultrasonic wave, and the gas flow rate is obtained by multiplying the flow rate by the area through which the gas passes. When the measuring tube is submerged, the propagation time of the ultrasonic wave changes and the passage area of the gas changes, which causes a problem that an error occurs in the measurement of the gas flow rate.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide an ultrasonic gas meter that does not cause a measurement error even if water contained in a gas pipe enters the gas meter.

In order to solve the above-described conventional problems, an ultrasonic meter according to the present invention includes a flow path member formed of an I-shaped tubular member that forms a flow path from an inlet to an outlet formed at both ends. A substantially cylindrical measurement tube attached to an opening provided in the flow path member, a pair of ultrasonic wave propagation means installed at a predetermined interval on the upstream side and downstream side of the measurement tube, and ultrasonic wave propagation A flow rate detecting means for calculating a flow rate of the gas flowing in the measuring tube based on a detection signal output from the means, and an opening provided in the flow path member, and the flow path based on the flow rate calculated by the flow rate detecting means. Including a shut-off device that shuts off the flowing gas, and the axis of the measuring tube is installed in the vertical direction.

  As a result, even if water enters the gas meter, it flows from the inlet to the outlet and does not stay in the measuring pipe, so that it is possible to eliminate a measurement error caused by the water intrusion.

  The ultrasonic gas meter of the present invention can eliminate measurement errors caused by water intrusion.

1 is an exploded perspective view showing a configuration of an ultrasonic gas meter according to Embodiment 1 of the present invention. AA sectional view shown in FIG. Installation form diagram of ultrasonic gas meter in Embodiment 1 of the present invention Sectional view of a conventional ultrasonic gas meter

1st invention is attached to the flow-path member comprised from the I-shaped cylindrical member which comprises the flow path from the inflow port formed in both ends to the outflow port, and the opening part provided in the flow-path member. Based on a substantially cylindrical measurement tube, a pair of ultrasonic wave propagation means installed at a predetermined interval on the upstream side and downstream side of the measurement pipe, and a detection signal output from the ultrasonic wave propagation means A flow rate detecting means for calculating a flow rate of the gas flowing in the pipe, and a shut-off device attached to an opening provided in the flow path member and blocking the gas flowing in the flow path based on the flow rate calculated by the flow rate detecting means; Since the measurement tube axis is installed in the vertical direction, even if water enters the gas meter, the water flows from the inlet to the outlet and does not stay in the measurement tube. Measurement errors that occur can be eliminated

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is an exploded perspective view showing a configuration of an ultrasonic gas meter according to Embodiment 1 of the present invention.

  In FIG. 1, a flow path member 11 has gas inlets 12 and outlets 13 disposed on both ends of an I-shaped cylindrical member on a substantially vertical axis i. The flow path 11a to 13 is comprised. Further, the flow path member 11 is provided with an opening 14 for attaching the gas shut-off valve 19 between the inlet 12 and the outlet 13 and an opening 15 for attaching a substantially cylindrical measuring tube 20 for measuring the gas flow rate. .

  A partition plate 17 having an opening matched to the valve body 19a of the gas shut-off valve 19, a gas shut-off valve 19 and a valve lid 16 are attached to the opening 14 via a shut-off valve support plate 18 in this order. .

  A measurement pipe 20 that matches the inner diameter of the flow path member 11, a control device 23 that controls the gas meter 10 that calculates the gas flow rate and drives the gas shut-off valve 19, and a cover 22 are attached to the opening 15 in order. ing. A pair of ultrasonic wave propagation means 21 a and 21 b for transmitting and receiving ultrasonic signals to each other is attached to the measurement tube 20 with a predetermined interval.

The control device 23 includes a battery 23a serving as a driving power source, a microcomputer 23b that controls a main part of the control, a wireless communication device 23c that communicates with an external wireless base station and terminal equipment, and the like.

  Although not shown, the gas cutoff valve 19 and the ultrasonic wave propagation means 21a, 21b are connected to the control device 23 by lead wires.

  FIG. 2 shows a cross-sectional view of the ultrasonic gas meter according to Embodiment 1 of the present invention.

  2 is a cross-sectional view taken along the line AA in the configuration diagram of FIG.

  The gas on the upstream side (inlet 12 side) is not leaked outside the gas meter 10 while maintaining airtightness between the cutoff valve support plate 18 and the flow path member 11 and between the cutoff valve support plate 18 and the gas cutoff valve 19. It is like that. Further, the airtightness between the flow path member 11 and the partition plate 17 is maintained, and the valve body 19a when the gas shut-off valve 19 is shut off closes the opening of the partition plate 17, so that the upstream side (inlet 12 side) ) Gas is blocked so that it does not flow downstream (outlet 13 side).

  Further, airtightness is maintained between the measurement tube 20 and the flow path member 11 so that the gas on the downstream side (outlet 13 side) does not leak to the outside of the gas meter 10.

  The measuring tube 20 is disposed on a substantially vertical axis i connecting the inlet 12 and the outlet 13 of the flow path member 11, and gas passes through the measuring tube 20 from the inlet 12 toward the outlet 13. It is as. The pair of ultrasonic wave propagation means 21 a and 21 b are provided on the same side surface of the measurement tube 20, and are configured to transmit and receive ultrasonic signals to each other by reflecting ultrasonic waves at a point P on the inner wall of the measurement tube 20.

  The control device 23 is installed in a space partitioned by a cover 22 and a surface of the measurement tube 20 on which the ultrasonic wave propagation devices 21 a and 21 b are installed.

  FIG. 3 shows an installation form diagram of the ultrasonic gas meter according to Embodiment 1 of the present invention.

  The gas pipe 26 installed in the underground 24 is raised on the ground in the vicinity of the house 25. The gas meter 10 is installed at the rising portion of the gas pipe 26 so that the inlet 12 is on the gas supply side.

  About the ultrasonic gas meter comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, gas flowing into the inlet 12 from the pipe 26 passes through the opening of the partition plate 17, passes through the measuring pipe 20, flows out of the outlet 13, passes through the pipe 26, and is supplied to various gas appliances. The Since the inflow port 12 is installed on the lower side, the gas flows in the gas meter 10 from the bottom to the top. Since the inflow port 12, the outflow port 13, and the measuring tube 20 are arranged on the same axis i, the gas passes through the gas meter 10 almost linearly.

  The flow rate of the gas passing through the measurement tube 20 is calculated from the gas passage speed and the gas passage area of the measurement tube 20. In general, the gas passage speed is such that an ultrasonic signal is transmitted and received between the pair of ultrasonic propagation means 21a and 21b, and the difference between the ultrasonic propagation speed from the upstream side and the ultrasonic propagation speed from the downstream side is calculated. Use and calculate. The control device 23 receives the detection signals from the ultrasonic wave propagation means 21a and 21b, forms a waveform after amplification, and calculates the flow rate in the microcomputer 23b.

  The microcomputer 23b integrates the flow rate and calculates the amount of gas used. Further, when an excessive flow rate exceeding a predetermined value is detected or when an abnormal state occurs when the flow rate is detected continuously for a predetermined time or longer, the gas cutoff valve 19 is closed to stop the gas supply.

  The wireless communication device 23c transmits the amount of gas used and the occurrence of an abnormal event determined by the microcomputer 23b to the gas supply company via a wireless base station and a telephone line. In addition, the amount of gas used is transmitted by wireless communication with a terminal device for meter reading.

  As described above, in the present embodiment, the inlet 12, the outlet 13, and the measuring pipe 20 are coaxially arranged in the I-shaped channel member 11, and installed in the gas pipe with the axial direction as the vertical direction. As a result, the water that has entered the supply gas passes from the inlet 12 to the outlet 13 without staying in the gas meter 10 even if it reaches the gas meter 10, so that the measuring tube 20 is not infiltrated. Measurement errors that occur can be eliminated.

  In addition, since the measurement pipe 20 is built inside the flow path member 11, the measurement pipe 20 is made to flow in the external environment (for example, corrosion due to water leakage) and external stress (stress applied from the gas pipe). ), It is possible to reduce the deformation and deterioration of the measuring tube that plays an important role in measuring the flow rate, and the reliability and durability of the gas meter 10 can be improved.

  It is obvious that the same effect can be obtained even if the gas pipe is installed with the inlet 12 being the upper side and the outlet 13 being the lower side.

  Moreover, in this Embodiment, since the inflow port 12 and the outflow port 13 are coaxial, it becomes possible to cut and connect a part of existing gas piping, and can perform installation construction easily. Moreover, it becomes possible to install in a gas piping path | route, and it can install in a small area.

  Moreover, in this Embodiment, the flow path of gas becomes I character type, and the flow path resistance inside the gas meter 10 can be reduced.

  Moreover, in this Embodiment, since the ultrasonic propagation means 21a and 21b used as the pair were arrange | positioned on the same side surface of the measurement pipe | tube 20, the measurement pipe | tube 20 can be rationally arrange | positioned in the cylindrical flow-path member 11. FIG. Therefore, the gas meter 10 can be downsized. In addition, the lead wire can be taken out from one direction and connected to the control device 23, so that the configuration of the gas meter requiring airtightness can be simplified.

  In the present embodiment, in the configuration of the flow path from the inlet to the outlet, the measurement tube 20 is provided inside the flow path member 11 formed integrally from the inlet 12 to the outlet 13. However, the present invention is not limited to this configuration, and the flow path may be configured by sequentially connecting a plurality of flow path members and measurement tubes from the inlet to the outlet.

  In the present embodiment, the measurement tube is arranged so as to be substantially vertical. However, the present invention is not limited to this, and water may not stay in the measurement tube even when the shaft is inclined. A similar effect can be obtained.

  As described above, since the ultrasonic gas meter according to the present invention can eliminate measurement errors caused by water intrusion, gas flow velocity measurement, flow measurement, etc. in an environment where condensation occurs inside the pipe It can be applied to other uses.

DESCRIPTION OF SYMBOLS 10 Gas meter 11 Flow path member 11a Flow path 12 Inlet 13 Outlet 19 Gas shut-off valve (shut-off device)
20 Measuring tube 21a, 21b Ultrasonic wave propagation means 23b Microcomputer (flow rate detection means)
i axis

Claims (1)

A flow path member configured from an I-shaped cylindrical member that forms a flow path from the inlet to the outlet formed at both ends;
A substantially cylindrical measuring tube attached to an opening provided in the flow path member ;
A pair of ultrasonic wave propagation means installed at a predetermined interval on the upstream side and downstream side of the measurement tube;
A flow rate detection means for calculating a flow rate of the gas flowing in the measurement tube based on a detection signal output by the ultrasonic wave propagation means;
A blocking device that is attached to an opening provided in the flow path member and blocks gas flowing in the flow path based on the flow rate calculated by the flow rate detection means,
The axis of the measuring tube is installed in the vertical direction,
Ultrasonic gas meter.