Automatic meter reading system and automatic meter reading method

Abstract

To provide a communication system, origination device, and communication method capable of performing automatic meter-reading regardless of a wire and a mobile line / IoT radio or the like.SOLUTION: A meter-reading system 303 includes: a flow meter 11 for measuring a flow rate of tap water flowing through a water pipe 50; a flow rate origination device 30 having an origination function (speaker) for originating a sonic wave with respect to the water pipe 50 whose flow rate is to be measured by the flow meter 11; and a flow rate collection device 40 arranged at a place separated from the flow meter 11 and having a reception function (microphone) for receiving the sonic wave from the water pipe 50 of the system being the same as that of the water pipe with the flow meter 11 arranged therein. In the meter-reading system 303, the flow rate reception device 40 can acquire a flow rate from the flow rate origination device 30 by a sonic wave with water inside the water pipe 50 or the water pipe 50 as a communication medium.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a communication system, a transmitting device, and a communication method for transmitting a physical quantity of a fluid in a pipe located at a distance using the pipe or the fluid. [Background technology]

[0002] In water supply services, flow meters are installed on the water pipes that connect to the homes and businesses that use the service, and the flow rate is measured to charge the customer according to the amount of water used. The process of obtaining this flow rate measurement is called meter reading here.

[0003] This meter reading has traditionally been done visually by meter readers, but manual meter readings have had issues such as difficulty in reading depending on the installation location, discrepancies in the date and time of reading, increased costs due to the need for manpower, and the difficulty in securing meter readers.

[0004] Therefore, communication lines have been used for meter reading without manual intervention (here called automatic meter reading) (see, for example, Non-Patent Document 1). Specifically, analog telephone lines and ISDN lines have been used in the past, but in recent years mobile lines, ADSL and optical lines have also been used (see, for example, Non-Patent Document 2).

[0005] A system model for automatic meter reading is shown in Figure 1. A central terminal 10 having a flow meter 11 reports the flow rate to a central device 20 connected via wired / wireless, allowing the central device to read the meters of flow meters installed in multiple homes, businesses, etc. without manual intervention. Furthermore, automation using wireless technology for IoT, such as LPWA (Low Power Wide Area), that avoids wired communication lines and mobile devices has also been proposed (see, for example, Non-Patent Document 3). [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Seiji Watanabe, "Recent Automatic Meter Reading Systems, Measurement and Control", 1978, Vol. 17, No. 12, pp. 899-906 [Non-patent document 2] https: / / www.ntt-tc.co.jp / service / kensin / water.html (accessed March 31, 2020) [Non-patent document 3] Susumu Matsui, "Technological Trends of IoT Systems and Efforts Towards Practical Use," IEICE Transactions on Information and Communication Engineers, C, J100-C, 4, pp. 151-158 (2017). Summary of the Invention [Problem to be solved by the invention]

[0007] Unlike gas meters and electricity meters, water flow meters are often installed underground rather than above ground or in exposed outdoor locations, making it difficult to install wiring or receive radio waves. This has made automatic meter reading difficult via wired, mobile lines, IoT wireless, etc.

[0008] Therefore, in order to solve the above problems, the present invention aims to provide a communication system, a transmitting device, and a communication method that enable automatic meter reading regardless of whether it is wired or via mobile lines / IoT wireless or the like. [Means for solving the problem]

[0009] In order to achieve the above object, the communication system according to the present invention transmits measurement data from a water flow meter by means of a water pipe or a sound wave signal using the water in the water pipe as a medium.

[0010] Specifically, the communication system according to the present invention comprises: a transmitter that transmits sound waves to an installed pipe or a fluid in the pipe; a receiver that receives the acoustic waves propagating through the pipe or the fluid; Equipped with.

[0011] Furthermore, the transmitting device according to the present invention comprises: a measuring instrument for measuring a physical quantity of a fluid in an installed pipe; a transmitter that modulates the physical quantity measured by the measuring device using an arbitrary modulation method to generate a sound wave and transmits the sound wave to the pipe or the fluid; Equipped with.

[0012] Furthermore, the communication method according to the present invention comprises: transmitting acoustic waves to the installed pipe or the fluid within said pipe; and receiving the acoustic waves propagating through the piping or the fluid; Do the following.

[0013] This communication system, this transmitting device, and this communication method communicate using installed pipes and the fluid inside them, making automatic meter reading possible even in places where wiring is difficult or where radio waves are difficult to reach. Therefore, the present invention can provide a communication system, transmitting device, and communication method that enable automatic meter reading without relying on wired or mobile lines / IoT wireless, etc.

[0014] The communication system of the present invention further includes a measuring instrument that measures a physical quantity related to the fluid, and the transmitter generates the sound wave by modulating the physical quantity measured by the measuring instrument using an arbitrary modulation method.

[0015] The communication system according to the present invention is characterized by further comprising a management device that communicates with the receiver by a medium other than the acoustic wave and collects information about the acoustic wave from the receiver.

[0016] The communication system according to the present invention is characterized by further comprising a power generator that generates power using the physical quantity of the fluid and supplies the power to at least one of the transmitter and the receiver.

[0017] The above inventions can be combined as much as possible. [Effects of the Invention]

[0018] The present invention can provide a communication system, a transmitting device, and a communication method that enable automatic meter reading regardless of whether it is wired or via mobile lines / IoT wireless or the like. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating an automatic meter reading system. [Figure 2] 1 is a diagram illustrating a communication system according to the present invention. [Figure 3] 1 is a diagram illustrating a communication system according to the present invention. [Figure 4] 1 is a diagram illustrating a communication system according to the present invention. [Figure 5] 1 is a diagram illustrating a communication system according to the present invention. [Figure 6] 1 is a diagram illustrating a communication system according to the present invention. [Figure 7] 1 is a diagram illustrating a communication system according to the present invention. [Figure 8] 1 is a diagram illustrating a communication system according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] The following description of the preferred embodiments of the present invention will be given with reference to the accompanying drawings. The preferred embodiments described below are examples of the present invention, and the present invention is not limited to the preferred embodiments. In this specification and the drawings, components having the same reference numerals are intended to represent the same components. In the following explanation, an example will be given in which the piping is a water pipe and the fluid is tap water, but the present invention is not limited to this example and can be applied to systems that flow gases or liquids.

[0021] (Embodiment 1) In this embodiment, a communication system is described that includes a transmitter that transmits sound waves to an installed pipe or a fluid in the pipe, and a receiver that receives the sound waves propagating through the pipe or the fluid. The communication system further includes a measuring device that measures a physical quantity related to the fluid. The transmitter generates the sound waves by modulating the physical quantity measured by the measuring device using an arbitrary modulation method.

[0022] FIG. 2 shows an example in which the communication system of this embodiment is applied to a water meter reading system 301. The meter reading system 301 includes: a flowmeter 11 for measuring the flow rate of tap water flowing through the water pipe 50; a flow rate transmitter 30 having a transmitting function (speaker) for transmitting sound waves to a water pipe 50 whose flow rate is measured by the flow meter 11; a flow rate collecting device 40 that is disposed at a location remote from the flow meter 11 and has a receiving function (microphone) for receiving the sound waves from a water pipe 50 of the same system as the water pipe in which the flow meter 11 is disposed; Equipped with. That is, in the meter reading system 301, the flow rate receiving device 40 can acquire the flow rate from the flow rate transmitting device 30 by sound waves using the water in the water pipe 50 or the water pipe 50 as a communication medium.

[0023] The transmitter corresponds to the flow rate transmitting device 30, the receiver corresponds to the flow rate collecting device 40, and the measuring device corresponds to the flow meter 11.

[0024] (Embodiment 2) Here, the flow rate transmitting device 30 and the flow rate receiving device 40 do not depend on the direction of the water flow.

[0025] First, a meter reading system 302 will be described in which a flow rate transmitting device 30 is located upstream and a flow rate receiving device 40 is located downstream. Fig. 3 is a diagram illustrating the meter reading system 302. The meter reading system 302 further comprises a management device (center device 20) that communicates with a receiver (flow rate receiving device 40) by a medium other than sound waves and collects sound wave information (flow rate) from the receiver (flow rate receiving device 40), in addition to the meter reading system 301 described in Fig. 2.

[0026] The meter reading system 302 comprises a center terminal 10 placed on a water pipe 50, and a center device 20 installed at a different location from the center terminal 10 via a wired / wireless line 60 or the like. The center terminal 10 has the flow meter 11, flow rate transmitting device 30, and flow rate receiving device 40 described in the meter reading system 301. The meter reading system 302 notifies the flow rate measured by the flow meter 11 from the flow rate transmitting device 30 to the flow rate receiving device 40 via the water pipe 50, and further reports the flow rate information from the flow rate receiving device 40 to the center device 20 via the line 60.

[0027] The line 60 is an existing line that is installed separately within the home / business and that communicates with the outside world. The flow rate measured by the flow meter 11 installed on the water pipe 50 within the home / business can be transmitted to the line 60 via the flow rate transmitting device 30 and the flow rate receiving device 40, and notified to the center device 20. The meter reading system 302 has the advantage that if the flow rate receiving device 40 is installed in a location that is easy to connect to the line 60, there is no need to move the position of the flow meter 10 or install new wiring.

[0028] (Embodiment 3) Next, a meter reading system 303 will be described in which a flow rate receiving device 40 is located upstream and a flow rate transmitting device 30 is located downstream. Fig. 4 is a diagram illustrating the meter reading system 303. The meter reading system 303 is a center-type system in which a flow rate receiving device 40 as a center device 20 can collect information from flow rate transmitting devices 30 of a plurality of center terminals 10 of different users. At this time, in order for the flow rate receiving device 40 to identify different flow rate transmitting devices 30, it is preferable that the flow rate transmitting device 30 attaches a unique identifier to the information it transmits.

[0029] The meter reading system 303 can connect the flow meters 11 of multiple homes / businesses (center terminals 10) to the center device 20 by using a flow transmitting device 30 and a flow receiving device 40. By using the water pipes 50, the meter reading system 303 can perform automatic meter reading for multiple homes / businesses without using new lines.

[0030] (Embodiment 4) Fig. 5 is a diagram illustrating a central meter reading system 304 of this embodiment. The water pipes 50 are not shown in Fig. 5. The meter reading system 304 has a configuration in which one central device 20 is connected to multiple central terminals 10 via lines 60. Furthermore, each central terminal 10 has a configuration in which one flow rate receiving device 40 receives flow rates from multiple flow rate transmitting devices 30, as described in Fig. 4.

[0031] The flow rate receiving device 40 in a central system does not necessarily have to be placed in the water delivery facility. Considering the reach of sound waves, it is preferable to place the flow rate receiving devices 40 in units where the flow rate transmitting device 30 for each water pipe 50 is grouped together with the branch of the water pipe 50, as shown in Figure 5. The central device 20 may manage multiple flow rate receiving devices 40 using a line 60, as explained in Figure 3. In other words, the multiple flow rate transmitting devices 30 and flow rate receiving devices 40 can be considered as a single central terminal 10 and connected to the central device 20.

[0032] (Embodiment 5) It may also be configured as shown in Fig. 6. Fig. 6 is a diagram for explaining a meter reading system 305. The meter reading system 305 is configured by combining the meter reading system 303 of Fig. 4 and the meter reading system 304 of Fig. 5. The flow rate transmitting devices (30-1, 30-2) and the flow rate receiving device 40-1 are configured as the meter reading system 303 of Fig. 4. On the other hand, the flow rate transmitting device 30-3, the flow rate receiving device 40-2, and the center device 20 are configured as the meter reading system 304 of Fig. 5.

[0033] (Embodiment 6) In the first to fifth embodiments, the measuring device is a flowmeter 11 that measures the flow rate of tap water. The measuring device is not limited to measuring flow rate, but may also measure physical quantities such as turbidity, color, and residual chlorine concentration as well as the condition and quality of the water pipes and tap water. In this case, the flow rate transmitting device 30 transmits the physical quantity to the flow rate receiving device 40 using sound waves.

[0034] (Embodiment 7) In this embodiment, a description will be given of a flow rate transmitting device 30 and a flow rate receiving device 40. FIG.

[0035] The flow rate transmitting device 30 has a flow meter 11, a transmitting unit 13 such as a speaker, and a reading / control unit 12. The reading / control unit 12 acquires the value of the flow meter 11, controls the timing of transmission of the value, and modulates it using an appropriate sound wave modulation method. The transmitting unit 13 converts the modulated flow rate value into sound waves and transmits them to the water pipe 50 or the water in the water pipe 50.

[0036] The flow rate receiving device 40 has a receiving unit 24 such as a microphone, and a control unit / output unit 22. The receiving unit 24 acquires sound waves transmitted by the flow rate transmitting device 30 from the water pipe 50 or the water in the water pipe 50. The control unit / output unit 22 converts the sound wave signal acquired by the receiving unit 24 into a flow rate value and outputs a signal that can be read by an external device.

[0037] The timing at which the reader / control unit 12 acquires the flow rate and transmits sound waves may be based on a timer or the time of day. The timing may also be in response to a request from the flow rate receiving device 40. In this case, two-way communication is required between the flow rate transmitting device 30 and the flow rate receiving device 40. When two-way communication is performed, the flow rate transmitting device 30 further includes a receiving unit 14 such as a microphone, and the flow rate receiving device 40 further includes a transmitting unit 23 such as a speaker. The control unit / output unit 22 of the flow rate receiving device 40 causes the transmitting unit 23 to output sound waves of an instruction signal to the water pipe 50 or the water in the water pipe 50 at the desired timing.

[0038] The control unit / output unit 22 of the flow rate receiving device 40 causes the transmitting unit 23 to output sound waves of the instruction signal to the water pipe 50 or the water in the water pipe 50 at the desired timing. The receiving unit 14 of the flow rate transmitting device 30 receives the sound waves of the instruction signal transmitted from the flow rate receiving device 40 via the water pipe 50 or the water in the water pipe 50. The reading / control unit 12 obtains the flow rate from the flowmeter 11 based on the instruction signal. In this way, the operation of the flow rate transmitting device 30 can be controlled from the flow rate receiving device 40.

[0039] The transmitting unit 13 and the transmitting unit 23 can use either ultrasonic waves or audible waves, or both, as the sound waves to be transmitted.

[0040] In addition, the receiving unit (14, 24) not only receives sound waves from the transmitting unit (23, 13) of the opposite device, but may also receive sound waves from the transmitting unit (13, 23) of its own device, allowing echo cancellation during transmission to prevent deterioration of communication quality due to near-end crosstalk.

[0041] To achieve bidirectional communication, the transmitting units (13, 23) time-share their transmission timing. The time-sharing can be based on a timing signal from the flow rate receiving device 40. A guard time can also be set to account for the propagation time in water pipes. In order to achieve two-way communication, the transmitting units (13, 23) may divide their respective frequencies. Time division and frequency division may also be combined.

[0042] When a centralized meter reading system automatically transmits flow rates, it prevents interference between signals from multiple flow rate transmitting devices 30 by staggering the transmission times of each flow rate transmitting device 30, staggering the frequencies, or a combination of both.

[0043] The signal may also be coded to provide error detection.

[0044] The signal may also be encrypted to prevent tampering and eavesdropping.

[0045] If the receiver (14, 24) cannot receive the sound waves due to noise caused by water flow, the transmitter (13, 23) retransmits the signal at a different time. For example, water usage in homes is often instantaneous, and the water flow is often stopped, so it is preferable for the transmitter (13, 23) to retransmit the signal at this time.

[0046] In communication between the flow rate transmitting device 30 and the flow rate receiving device 40, waveform distortion of sound waves occurs due to the difference between the propagation time through the water pipe medium and the propagation time through the water medium. Alternatively, waveform distortion occurs due to multiple reflections of sound waves in the water medium. In order to correct these, it is preferable to perform communication between the flow rate transmitting device 30 and the flow rate receiving device 40 using OFDM (Orthogonal Frequency Division Multiplexing) modulation.

[0047] The flow rate transmitting device 30 can transmit the flow rate as well as the status of its own device, such as errors and remaining battery power, to the flow rate receiving device 40. This allows the center device 20 to remotely obtain information on the need for maintenance as well as meter reading. As a result, the administrator can perform maintenance only on the necessary equipment, rather than uniform maintenance based on the number of years since the installation of the flow meter 11. Similarly, the administrator can perform maintenance on each device before it stops or breaks down.

[0048] (Embodiment 8) The meter reading system described with reference to FIGS. 2 to 6 may further include a generator that generates electricity using the physical quantity of the fluid and supplies the power to at least one of the transmitter and the receiver. The flow rate transmitting device 30 or the flow rate receiving device 40 can have a power generator such as a thermoelectric converter or a power generator using water flow (hereinafter referred to as a hydroelectric power generator) to generate its own power. The flow rate transmitting device 30 or the flow rate receiving device 40 also has a storage battery, and the power generator can charge the storage battery.

[0049] For example, the flow rate transmitting device 30 or the flow rate receiving device 40 can convert vibrations of water pipes caused by water flow or vibrations of the earth's crust where they are installed into electricity. The power generator can extend the life of the primary battery required to operate the flow rate transmitting device 30 or the flow rate receiving device 40, or can eliminate the need for a primary battery.

[0050] 8 is a diagram illustrating an example of a thermoelectric converter 70 that utilizes the temperature difference between a water pipe and the ground or the outside air. The thermoelectric converter 70 includes a first heat exchanger 71, a second heat exchanger 72, a heat transfer unit 73, and an installation box lid 74. The first heat exchanger 71 exchanges heat with the water pipe 50 and the water in the water pipe 50. Here, the first heat exchanger 71 can also be integrated with the flow rate transmitting device 30. The second heat exchanger 72 can efficiently exchange heat with the ground surface by being installed on the front surface of the lid 74. The heat exchanger 73 is made of a material with a high heat transfer coefficient, and can efficiently exchange heat by being attached to the back surface of the lid 74 or by being integrated with the metal lid 74.

[0051] Heat from the first heat exchange unit 71 is transferred via the heat transfer unit 73 to the thermoelectric element provided in the second heat exchange unit 72, or heat from the second heat exchange unit 72 is transferred via the heat transfer unit 73 to the thermoelectric element provided in the first heat exchange unit 71. This enables thermoelectric conversion using the temperature difference between the temperature near the ground and the water temperature. While the water temperature is fairly stable, the outside air temperature changes significantly depending on environmental changes such as weather, season, and time of day, which can easily cause a temperature difference with the water temperature. This temperature difference is used to generate electricity, which is supplied to the flow rate transmitting device 30 or the flow rate receiving device 40.

[0052] A hydroelectric power generation device may be used as the power generator. A hydroelectric power generation device may utilize a turbine generator that converts the water flow in the water pipe into electricity. If an impeller type flow meter is used, the impeller type may be used in common, and the rotation of its rotating shaft may be transmitted to a generator motor via gears or the like. Furthermore, a hydroelectric power generation device imposes a load on the water flow, which reduces the load on the water supply pump or the water pressure at the faucet. Therefore, power generation can be stopped when the power generation efficiency decreases, such as when the water pressure decreases. Furthermore, power generation can be stopped when the storage battery is sufficiently charged.

[0053] (effect) This meter reading system uses water pipes and the water in them as a communication medium for sonic signals, allowing automatic meter reading in places where wireless / wired lines are physically difficult to use. For example, this meter reading system can transmit information such as flow rate to places where wired / wireless lines are easily accessible. Furthermore, when it is difficult to supply electricity, this meter reading system can operate continuously by equipping it with a generator and storage battery. [Industrial Applicability]

[0054] The communication system according to the present invention can be applied to reading water flow meters installed in homes and businesses, and to measuring the quality of water pipes and tap water. [Explanation of symbols]

[0055] 10: Center terminal 11:Flow meter 12: Read / control unit 13: Transmission Department 14: Receiving unit 20: Center device 22: Control / output section 23: Transmission Department 24: Receiving unit 30: Flow rate transmitter 40: Flow rate receiving device 50: Water pipe 60: Line 70: Thermoelectric conversion device 71: 1st heat exchange section 72:Second heat exchange section 73:Heat exchange section 74: Lid 301~305: Meter reading system

Claims

1. a plurality of first transmitters arranged in each of the branched first pipes of the laid first pipes that branch into a plurality of first pipes, and that transmit first acoustic waves to the first pipes or to a fluid in the first pipes; a first receiver disposed in the first pipe before the branching, for receiving the first acoustic wave propagating through the first pipe or the fluid in the first pipe; a first communication system comprising: a plurality of second transmitters arranged in each of the branched second pipes of the laid second pipes that branch into a plurality of second pipes, and transmitting second acoustic waves to the second pipes or to the fluid in the second pipes; a management device that is disposed in the second pipe before the branching and has a second receiver that receives the second acoustic wave propagating through the second pipe or the fluid in the second pipe; A second communication system comprising: It is equipped with The automatic meter reading system is characterized in that the first receiver transmits information about the received first sound wave to the management device via a communication line.

2. the first communication system further includes a first measuring device that measures a first physical quantity related to the fluid in the first pipe; the second communication system further includes a second measuring instrument that measures a second physical quantity related to the fluid in the second pipe; The first transmitter modulates the first physical quantity measured by the first measuring device using an arbitrary modulation method to generate the first sound wave. The second transmitter modulates the second physical quantity measured by the second measuring device using an arbitrary modulation method to generate the second sound wave.

2. The automatic meter reading system according to claim 1,

3. The automatic meter reading system according to claim 1 or 2, characterized in that the first communication system further comprises a generator that generates electricity using a physical quantity of a fluid in the first pipe and supplies power to at least one of the first transmitter and the first receiver.

4. The automatic meter reading system according to claim 1 or 2, characterized in that the second communication system further comprises a generator that generates electricity using a physical quantity of a fluid in the second pipe and supplies power to at least one of the second transmitter and the second receiver.

5. disposing a first transmitter in each of the first pipes at branch destinations of the laid first pipes that branch out from one pipe to a plurality of pipes; disposing one first receiver in the first pipe before the branching; transmitting a first acoustic wave from the first transmitter to the first pipe or to a fluid within the first pipe; receiving the first acoustic wave propagating through the first pipe or the fluid in the first pipe with the first receiver; disposing a second transmitter in each of the second pipes at branch destinations of the laid second pipes that branch out from one to a plurality of pipes; disposing a management device having one second receiver in the second pipe before the branching; transmitting a second acoustic wave from the second transmitter to the second pipe or to a fluid within the second pipe; receiving the second acoustic wave propagating through the second pipe or the fluid in the second pipe with the second receiver; and transmitting information about the first sound wave received by the first receiver to the management device via a communication line; An automatic meter reading method characterized by:

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