Water leak detection system

Abstract

To facilitate detection of a water leak from piping with high sensitivity.SOLUTION: A vibration sensor unit 100 has a vibration sensor 110 that detects vibrations of water in tap water piping 500 and generates vibration data D110. A wireless communication device 400 can wirelessly transmit and receive data. A power source 250 supplies power. A control device 200 is electrically connected to the vibration sensor 110, the wireless communication device 400, and the power source 250, and acquires the vibration data D110 from the vibration sensor 110, generates piping condition data D200 based on the acquired vibration data D110, and causes the wireless communication device 400 to generate transmission data D201 including the generated piping condition data and to transmit it to a water piping management server 3. A holding member 300 is held by the piping 500 at one end inside the piping 500, and holds the vibration sensor unit 100 in a position not in contact with an inner wall of the piping.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a water leak detection system. [Background technology]

[0002] Water pipes buried underground (referred to as "buried pipes") are buried underground, so it is not easy to detect a leak when one occurs. A method is known in which a listening rod or the like is used in the ground above the buried pipe to detect vibrations caused by a leak in the buried pipe. Also known is a leak detection system that can remotely detect the presence or absence of a leak in the buried pipe based on information about vibrations of the buried pipe detected and transmitted by a vibration sensor terminal having wireless communication capabilities that is placed on the outer wall of the buried pipe.

[0003] Generally, the larger the diameter of a water pipe, the thicker the pipe, so the vibration of the pipe caused by a water leak becomes smaller and the attenuation of the vibration over the distance it travels through the pipe becomes greater. As a result, the larger the diameter of the water pipe, the narrower the water leak detection range of the vibration sensor terminal and the shorter the installation interval of the vibration sensor terminal.

[0004] In this specification, water pipes with an inner diameter of about 75 mm to 5000 mm are referred to as "large pipes". Large pipes are often buried deep, and are often laid under main roads. For this reason, the installation locations of vibration sensor terminals for large pipes are limited. Therefore, it is necessary to install vibration sensor terminals with relatively high sensitivity that can widen the water leakage detection range for large pipes so that vibrations of the large pipes can be detected even if the installation intervals of the vibration sensor terminals are long. Therefore, the vibration sensor terminals to be installed in large pipes are required to have higher sensitivity than the vibration sensor terminals to be installed in small and medium diameter pipes.

[0005] Therefore, there is a technique for detecting the leakage sound of a large-mouth pipe using a vibration sensor terminal with a relatively high sensitivity. For example, Patent Document 1 describes a leakage sound detection device having a sound collection section, a main body section, a connection section, and a fitting section. Here, the sound collection section has a peripheral wall section that gradually expands in diameter downward in order to detect vibrations. The lower end of the peripheral wall section is an open end. The main body section has a housing. The lower end of the housing has the upper end of the sound collection section fixed thereto, and a piezoelectric element used to detect vibrations transmitted to the sound collection section is installed therein. The fitting section is a buffer member made of an elastic material and provided between the lower housing and the upper housing of the housing. The fitting section is formed so that the fitting section can be fixed to the large-mouth pipe. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2005-283169 A Summary of the Invention [Problem to be solved by the invention]

[0007] The water leakage sound detection device described in Patent Document 1 measures vibrations while attached to a fire hydrant installed at a branch point of the pipe. Therefore, the water leakage sound detection device described in Patent Document 1 may erroneously detect vibrations that are not related to water leakage and are transmitted from the surroundings of the fire hydrant as vibrations due to water leakage.

[0008] An object of the present invention is to provide a water leak detection system that makes it easy to detect water leaks in piping with high sensitivity. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, one aspect of the water leakage detection system of the present invention is a water leakage detection system comprising a vibration sensor unit, a control device, a wireless communication device, a power source, and a holding member, wherein the vibration sensor unit has a vibration sensor that detects vibrations of water in a water pipe and generates vibration data, and is positioned so as to be submerged in a position that does not contact the inner wall of the water pipe, the wireless communication device can transmit and receive data wirelessly, the power source supplies power to the vibration sensor unit, the control device, and the wireless communication device, the control device is electrically connected to the vibration sensor, the wireless communication device, and the power source, acquires the vibration data from the vibration sensor, generates pipe status data including information on the status of the pipe based on the acquired vibration data, causes the wireless communication device to generate transmission data including the generated pipe status data, and further causes the wireless communication device to transmit the generated transmission data to a water pipe management server, and the holding member is held to the pipe at one end inside the pipe, and holds the vibration sensor unit in a position that does not contact the inner wall of the pipe. Effect of the Invention

[0010] According to a representative embodiment of the present invention, it is possible to easily detect water leakage from piping with high sensitivity. Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of the configuration of a water leakage detection system according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram illustrating an example of a functional block diagram of the water leakage detection system according to the first embodiment. [Diagram 3] FIG. 3 is a block diagram illustrating an example of signal processing in the water leakage detection system according to the first embodiment. [Figure 4] FIG. 4 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the first embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Diagram 5]FIG. 5 is a schematic explanatory diagram showing an example of a state in which the water leak detection system of the first embodiment is installed, including a cross-sectional view of a diameter surface of a pipe. [Figure 6] FIG. 6 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the second embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Figure 7] FIG. 7 is a schematic explanatory diagram showing an example of a state in which the water leak detection system of the third embodiment is installed, including a cross-sectional view of a diameter surface of a pipe. [Figure 8] FIG. 8 is a schematic explanatory diagram showing an example of a state in which the water leak detection system of the fourth embodiment is installed, including a cross-sectional view of a diameter surface of a pipe. [Figure 9] FIG. 9 is a schematic explanatory diagram showing an example of a state in which the water leak detection system of the fifth embodiment is installed, including a cross-sectional view of a diameter surface of a pipe. [Figure 10] FIG. 10 is a schematic explanatory diagram showing an example of a state in which the length of the holding member of the water leakage detection system according to the fifth embodiment of FIG. 9 is changed. [Figure 11] FIG. 11 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the sixth embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Figure 12] FIG. 12 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the seventh embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Figure 13] FIG. 13 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the eighth embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Figure 14] FIG. 14 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system of the ninth embodiment is installed, including a cross-sectional view in the extension direction of the piping. [Figure 15] FIG. 15 is a block diagram showing an example of a functional block diagram of a water leakage detection system according to a ninth embodiment. [Figure 16] FIG. 16 is a block diagram showing an example of a functional block diagram of a water leakage detection system according to a tenth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not to be interpreted as being limited to the description of the embodiment shown below. It will be easily understood by those skilled in the art that the specific configuration can be changed without departing from the concept or purpose of the present invention.

[0013] In the configurations of the invention described below, the same or similar configurations or functions are given the same reference numerals, and duplicated explanations are omitted.

[0014] In this specification, the terms "first," "second," "third," and the like are used to identify components and do not necessarily limit the number or order.

[0015] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings, etc. may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not limited to the position, size, shape, range, etc. disclosed in the drawings, etc. EXAMPLES

[0016] <Outline of the vibration sensor unit 100> Fig. 1 is a diagram showing an example of the configuration of a water pipe management system 1000. As shown in Fig. 1, the water pipe management system 1000 includes a water leak detection system 1 that is attached to a large water pipe 500 and detects vibrations, a wireless device 2 that wirelessly receives information about water leaks in the large pipe 500 transmitted from the water leak detection system 1 and transfers the received information to a water pipe management server 3, and a water pipe management server 3 that receives the information about water leaks in the large pipe 500 from the wireless device 2. The wireless device 2 and the water pipe management server 3 are connected to a network NW. A user terminal 4 is connected to the network NW.

[0017] The water piping management system 1000 is a system that detects water leakage vibrations caused by water W inside a large pipe 500 leaking out of the large pipe 500 using a vibration sensor 110 installed inside the large pipe 500, and accumulates information regarding the detected water leakage vibrations from the large pipe 500 in a water piping management server 3.

[0018] The large pipe 500 is a water pipe with an inner diameter of 75 mm or more and 5000 mm or less. As described below, the water leakage detection system 1 uses a holding member 300 to hold the vibration sensor 110 used for detecting water leakage in a position where it does not contact the inner wall of the large pipe 500. The large pipe 500 is an example of a water pipe to which the water leakage detection system 1 is attached.

[0019] The large pipe 500 may leak due to corrosion of the large pipe 500 or damage caused by a physical impact from the outside of the large pipe 500. The location of the leak in the large pipe 500 is referred to as a "leak point 501."

[0020] The water leakage detection system 1 includes a vibration sensor unit 100 having a vibration sensor 110, a control device 200 electrically connected to the vibration sensor 110 via a cable 150, a power source 250, a holding member 300 that holds the vibration sensor unit 100 inside a large pipe 500, and a wireless communication device 400. The holding member 300 is held inside the large pipe 500 by being held by a holding tool 510 provided inside the large pipe 500. A portion of the holding member 300 that is not in contact with the holding tool 510 is not in contact with the inner wall of the large pipe 500. The holding member 300 holds the vibration sensor unit 100 inside the large pipe 500. In other words, the vibration sensor unit 100 is held by the holding member 300 at a position that is not in contact with the inner wall of the large pipe 500 and is submerged in water W. Therefore, the vibration sensor 110 is held inside the large pipe 500.

[0021] In FIG. 1, inside the large pipe 500, a holding member 300 held at the upper part of the large pipe 500 holds the vibration sensor unit 100 inside the large pipe 500. The arrangement of the holding member 300 and the vibration sensor unit 100 (including the position and orientation of the holding member 300 and the vibration sensor unit 100) shown in FIG. 1 and other figures is an example of the arrangement of the holding member 300 and the vibration sensor unit 100. The arrangement of the holding member 300 and the vibration sensor unit 100 may be any arrangement in which the holding member 300 holds the vibration sensor unit 100 inside the large pipe 500 (pipe). The arrangement of the holding member 300 and the vibration sensor unit 100 can be changed. For example, the orientation of the holding member 300 can be changed to be horizontal or diagonal. A holder 510 may be provided at a position other than the top of the large pipe 500, such as the side or bottom of the inner wall of the large pipe 500, and a holding member 300 held by the holder 510 at a position other than the top of the large pipe 500 may hold the vibration sensor unit 100 inside the large pipe 500.

[0022] The control device 200 acquires vibration data D110 of the large pipe 500 from the vibration sensor 110 via the cable 150. Then, the control device 200 generates pipe condition data D200 including information on the condition of the large pipe 500 based on the vibration data D110 acquired via the cable 150 (see FIG. 3).

[0023] The wireless communication device 400 generates transmission data D201 including the piping condition data D200, and transmits the transmission data D201 to the water piping management server 3 via the wireless device 2. Note that, although details will be described later, the wireless communication device 400 may also have a function of receiving the transmission data D202 transmitted from the water piping management server 3 or the wireless device 2, and transferring the transmission data D202 to the control device 200.

[0024] The wireless communication device 400 and the radio 2 are wirelessly connected. There is no limitation on the wireless system between the wireless communication device 400 and the radio 2. The wireless system may be, for example, a public line network such as LTE (Long Term Evolution) or LPWA (Low Power Wide Area), a wireless LAN (Local Area Network) connection using Wi-Fi, or a short-distance connection using Bluetooth.

[0025] The control device 200, the wireless communication device 400, and the power source 250 are housed inside the control device housing 240. This allows the control device 200, the wireless communication device 400, and the power source 250 to be regarded as a single device. Also, the control device 200, the wireless communication device 400, and the power source 250 may be separate entities rather than being housed in a single housing.

[0026] The wireless device 2 is connected to the network NW, and when it receives transmission data D201 including piping condition data D200 from the wireless communication device 400, it extracts the piping condition data D200 from the received transmission data D201 and transmits the piping condition data D200 to the water piping management server 3 via the network NW.

[0027] The water piping management server 3 receives and stores the piping status data D200 transmitted from the wireless device 2. The administrator can use the water piping management server 3 to obtain information D300 related to water leakage from the large pipe 500 from the stored piping status data D200. There is no restriction on the location where the water piping management server 3 is installed. The water piping management server 3 may be installed in a remote location away from the water leakage detection system 1 and the wireless device 2. The water piping management server 3 may be a server in an on-premise environment, or may be a server in a virtual environment built in a cloud environment.

[0028] The user terminal 4 is connected to the network NW, and can access the water piping management server 3 to obtain information D300 about water leakage (e.g., information about whether or not a leak has been detected from a large pipe 500) from the water piping management server 3. Furthermore, when a leak from a large pipe 500 is detected, the water piping management server 3 may transmit the information D300 about water leakage to the user terminal 4. The user terminal 4 is, for example, a personal computer, a smartphone, or a tablet terminal. There is no limit to the number of user terminals 4.

[0029] <<Configuration of Water Leak Detection System 1>> <Outline of the configuration of the water leak detection system 1> Fig. 2 is a block diagram showing an example of a functional block diagram of the water leakage detection system 1 of the embodiment 1. As shown in Fig. 2, the water leakage detection system 1 includes a vibration sensor unit 100, a control device 200, a wireless communication device 400, a power source 250, and a holding member 300.

[0030] The control device 200, the wireless communication device 400, and the power source 250 are housed inside the control device housing 240 outside the large pipe 500. This allows the control device 200, the wireless communication device 400, and the power source 250 to be regarded as a single device. The control device 200, the wireless communication device 400, and the power source 250 may be separate entities rather than being housed in a single housing. The wireless communication device 400 and the power source 250 may be provided outside the large pipe 500, and the control device 200 may be provided inside the large pipe 500 (for example, inside the vibration sensor unit 100).

[0031] The vibration sensor unit 100 has a vibration sensor 110. A cable 150 is connected to the vibration sensor 110. The cable 150 includes a power cable 151 and a signal cable 152. The power cable 151 is connected to a power source 250. The power source 250 supplies power to the vibration sensor 110 via the power cable 151. The signal cable 152 is connected to a control device 200. The signal cable 152 is a cable that transmits vibration data D110 including information on vibrations detected by the vibration sensor 110 to the control device 200. In order to easily ensure pressure resistance and waterproofing of the connection between the cable 150 and the vibration sensor unit 100, the cable 150 is connected to a connector 130 of the vibration sensor unit 100.

[0032] As described above, the holding member 300 holding the vibration sensor unit 100 is held at one end by the holder 510 inside the large pipe 500, and holds the vibration sensor unit 100 inside the large pipe 500. As described above, the arrangement of the holding member 300 and the vibration sensor unit 100 may be other than the arrangement in which the holding member 300 held at the top of the large pipe 500 shown in FIG. 2 holds the vibration sensor unit 100 inside the large pipe 500. For example, the orientation of the holding member 300 can be changed to be horizontal or diagonal. In addition, the holder 510 may be provided at a position other than the top of the large pipe 500, such as the side or bottom of the inner wall of the large pipe 500, and the holding member 300 held by the holder 510 at a position other than the top of the large pipe 500 may hold the vibration sensor unit 100 inside the large pipe 500. Furthermore, although the antenna 420 of the wireless communication device 400 is housed inside the control device housing 240 , the antenna 420 may be arranged to extend outward from the control device housing 240 .

[0033] The control device 200 has a processing unit 210 that executes processing, and a storage unit 220 that stores information. The processing unit 210 has a vibration data recording unit 211 and a signal processing unit 212. The storage unit 220 stores a vibration data log 221 that stores the vibration data D110 received from the vibration sensor unit 100, and a vibration analysis result data log 222 that stores the piping condition data D200 generated by the signal processing unit 212 of the processing unit 210 from the vibration data D110 through signal processing described later.

[0034] The control device 200 has, as its hardware configuration, a processor, a main storage device, a secondary storage device, an input device, an output device, a network I / F, and a bus connecting these. The processing unit 210 is a processor that reads data and programs stored in the secondary storage device into the main storage device and executes processing defined by the programs. The storage unit 220 is a secondary storage device.

[0035] The processing unit 210, the vibration data recording unit 211, and the signal processing unit 212 are realized by the processor reading out a program stored in a secondary storage device into the main storage device and executing it. Furthermore, in this specification, when a process is described in a sentence with the processing unit 210, the vibration data recording unit 211, and the signal processing unit 212, which are functional units, as the subject, it indicates that the processor is executing a program that realizes the functional unit.

[0036] Furthermore, the control device 200 may have a dedicated circuit such as a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or a complex programmable logic device (CPLD) instead of a processor.

[0037] The water pipe management server 3 and the user terminal 4 can be realized by adding an input / output device to the same hardware resources as the control device 200. The input / output device is an input device such as a keyboard or a mouse that acquires information input by a user's operation, an output device such as a display that outputs information, or a device such as a touch panel that inputs and outputs information.

[0038] Hereinafter, the processing of the vibration data recording unit 211 and the signal processing unit 212 in the processing unit 210 will be described. The vibration data recording unit 211 acquires the vibration data D110 transmitted by the vibration sensor 110 of the vibration sensor unit 100 to the control device 200 via the signal cable 152. Then, the vibration data recording unit 211 outputs the acquired vibration data D110 to the signal processing unit 212, and stores the vibration data D110 in the vibration data log 221.

[0039] The signal processing unit 212 executes signal processing, the details of which will be described below with reference to Fig. 3. In the signal processing, the signal processing unit 212 performs signal processing on the vibration data D110 acquired from the vibration data recording unit 211 to generate pipe condition data D200 including information on the condition of the large pipe 500. The signal processing unit 212 also stores the generated pipe condition data D200 in a vibration analysis result data log 222, and outputs the generated pipe condition data to the wireless communication device 400. Note that the signal processing unit 212 may read out the vibration data D110 used as input for signal processing from the vibration data log 221 instead of acquiring it from the vibration data recording unit 211.

[0040] The piping condition data D200 may be any data that includes information on the condition related to water leakage from the large piping 500. The piping condition data D200 may be the vibration data D110, or may be data obtained by extracting a portion of the data from the vibration data D110. In this manner, the signal processing may be a process of outputting the vibration data D110 as the piping condition data D200, or may be a process of extracting a portion of the data from the vibration data D110 and outputting the extracted data as the piping condition data D200.

[0041] Furthermore, for example, the piping condition data D200 may be information (referred to as "determination information") indicating whether or not the large piping 500 is leaking. When the determination information is used as the piping condition data D200, the signal processing unit 212 performs filter processing and FFT processing on the vibration data D110, and performs correlation analysis to determine whether or not the large piping 500 is leaking, and calculates the determination result as the determination information, for example, as shown in the example of the signal processing flowchart in Fig. 3.

[0042] Fig. 3 is a flowchart showing an example of signal processing in the water leakage detection system 1 of Example 1. As shown in Fig. 3, the signal processing unit 212 receives the vibration data D110 generated by the vibration sensor 110 from the vibration sensor 110 (step S1).

[0043] Next, the signal processing unit 212 performs a filter process on the vibration data D110 to remove noise from the vibration data D110 and extract features of the vibration data D110 (step S2). Next, the signal processing unit 212 performs a frequency analysis using FFT processing on the data obtained in step S2 to obtain frequency analysis data (step S3). Next, the signal processing unit 212 performs a correlation analysis on the frequency analysis data obtained in step S3 to extract features for each frequency of the frequency analysis data (step S4).

[0044] Next, the signal processing unit 212 performs a leak determination using the feature amount for each frequency of the frequency analysis data extracted in step S4, and calculates a determination result as to whether or not the large pipe 500 is leaking (step S5). Next, the signal processing unit 212 generates pipe condition data D200 from the determination result of step S5 (step S6).

[0045] Next, the signal processing unit 212 stores the piping condition data D200 generated in step S6 in the vibration analysis result data log 222, outputs the generated piping condition data D200 to the wireless communication device 400, and ends the signal processing (step S7). Here, instead of the signal processing unit 212 transmitting the piping condition data D200 to the wireless communication device 400 in step S7, the signal processing unit 212 may acquire the piping condition data D200 stored in the vibration analysis result data log 222 at a predetermined timing and output the acquired piping condition data D200 directly or after regenerating it to the wireless communication device 400. Here, the signal processing unit 212 may output a plurality of piping condition data D200 together to the wireless communication device 400.

[0046] 2, the wireless communication device 400 has a communication circuit 410 and an antenna 420. The communication circuit 410 generates transmission data D201 by adding header information and the like to the piping condition data D200 output from the signal processing unit 212 of the processing unit 210.

[0047] When the wireless communication device 400 acquires the piping condition data D200 from the signal processing unit 212, the wireless communication device 400 generates transmission data D201 by adding header information and the like to the piping condition data D200 using the communication circuit 410. Then, the wireless communication device 400 wirelessly transmits the generated transmission data D201 to the wireless device 2 using the antenna 420. Note that the signal processing unit 212 may generate the transmission data D201 from the piping condition data D200 and cause the wireless communication device 400 to transmit the transmission data D201 to the wireless device 2.

[0048] Furthermore, the wireless communication device 400 may have a function of receiving transmission data D202 transmitted from the wireless device 2 and transferring it to the control device 200. The transmission data D202 may include, for example, a program for processing the vibration data D110 of the processing unit 210, and commands for controlling the processing unit 210 and the vibration sensor 110. The processing unit 210 of the control device 200 may be configured to change the processing included in the signal processing (see FIG. 3) based on the received transmission data D202.

[0049] 2, the power source 250 is a power source that supplies power to the vibration sensor 110 of the vibration sensor unit 100, the processing unit 210 of the control device 200, the storage unit 220, the wireless communication device 400, etc. The power source 250 is a battery 250A such as a primary battery such as an alkaline battery, a rechargeable secondary battery such as a lithium ion secondary battery or a lead storage battery, or a fuel cell.

[0050] <Example of configuration of vibration sensor unit 100 and holding member 300, and installation state of water leakage detection system 1> Fig. 4 is a schematic explanatory diagram showing an example of an installed state of the water leakage detection system 1 of the first embodiment, including a cross-sectional view in the extension direction of the large pipe 500. Fig. 5 is a schematic explanatory diagram showing an example of an installed state of the water leakage detection system 1 of the first embodiment, including a cross-sectional view of a diameter surface of the large pipe 500. The cross section shown in Fig. 4 and the cross section shown in Fig. 5 are perpendicular to each other.

[0051] 4 and 5, the vibration sensor unit 100 has a vibration sensor 110, a vibration sensor unit housing 120, and a connector 130. Note that, in Fig. 4 and Fig. 5, the installation angle of the vibration sensor 110 is set perpendicular to the flow velocity direction as an example, but the installation angle of the vibration sensor 110 can be set freely.

[0052] The vibration sensor 110 may be any sensor capable of measuring a vibration waveform, and may be, for example, a capacitance type vibration sensor, a piezoelectric type vibration sensor, or an electrodynamic type vibration sensor made using MEMS (Micro Electro Mechanical Systems) technology.

[0053] The vibration sensor unit housing 120 is a case for the vibration sensor unit 100. Although the shape of the vibration sensor unit housing 120 is depicted as a rectangle in Fig. 4 and Fig. 5, the shape of the vibration sensor unit housing 120 may be a sphere, a cylinder, or a cone. The material of the vibration sensor unit housing 120 is, for example, metal, resin, or ceramics.

[0054] The vibration sensor unit housing 120 has a waterproof structure so that the water W in the large pipe 500 does not enter the internal space 120x of the vibration sensor unit housing 120. In addition, the vibration sensor unit housing 120 has a pressure resistance against a pressure equal to or greater than the pressure of the water W in the large pipe 500. For example, if the large pipe 500 is a ductile cast iron pipe and the design pressure resistance of the large pipe 500 is a maximum hydrostatic pressure of 0.75 MPa and a water hammer pressure of 0.55 MPa, it is desirable that the pressure resistance of the vibration sensor unit housing 120 is 1.3 MPa or more, which is the sum of 0.75 MPa (the maximum hydrostatic pressure which is the design pressure resistance of the large pipe 500) and 0.55 MPa (the water hammer pressure). In this way, it is desirable that the pressure resistance of the vibration sensor unit housing 120 is greater than the theoretical pressure (for example, the sum of the maximum hydrostatic pressure which is the design pressure resistance of the large pipe 500 and the water hammer pressure) that the vibration sensor unit housing 120 receives. This ensures sufficient pressure resistance against water pressure for the vibration sensor unit 100. Furthermore, the vibration sensor 110 can stably detect the vibration of the water W in the large pipe 500.

[0055] In order to easily ensure the pressure resistance and waterproofing of the vibration sensor unit housing 120, a connector 130 to which a cable 150 (power cable 151 and signal cable 152) is connected is used as an electrical path for the vibration sensor unit housing 120. As with the connector 130, a connector 241 is used for the control device housing 240 of the control device 200 in order to easily ensure the waterproofing of the control device housing 240. Note that, like the pressure resistance of the vibration sensor unit housing 120 described above, it is desirable to set the pressure resistance of the connector 130 to a pressure greater than the theoretical pressure that the connector 130 will receive (for example, the sum of the maximum hydrostatic pressure, which is the design pressure resistance of the large pipe 500, and the water hammer pressure).

[0056] The vibration sensor 110 detects vibration and outputs digital vibration data D110 to the control device 200 via the signal cable 152. By converting the vibration data D110 into digital data that is more resistant to electromagnetic noise than analog data, degradation of the vibration data D110 (reduction in the S / N ratio of vibration due to water leakage) is suppressed in the process of the vibration data D110 transmitting through the signal cable 152. As a result, even if the length of the signal cable 152 is set to 1 m or more, degradation of the vibration data D110 can be sufficiently suppressed in the process of the vibration data D110 transmitting through the signal cable 152. The digital transmission method of the vibration data D110, which is digital data, can be, for example, SPI (Serial Peripheral Interface), I2C (Inter-Integrated Circuit), or UART (Universal Asynchronous Receiver Transmitter).

[0057] Between the large pipe 500 and the vibration sensor unit housing 120 of the vibration sensor unit 100, there are a cable 150 (a power cable 151 and a signal cable 152) and a holding member 300. It is necessary to suppress a decrease in the sensitivity (S / N (Signal / Noise) ratio) of the vibration sensor 110 to vibrations due to water leakage caused by vibrations transmitted from the cable 150 and the holding member 300.

[0058] Therefore, the resonance frequency f300 of the holding member 300 and the resonance frequency f150 of the cable 150 (the power cable 151 and the signal cable 152) are higher than the frequency fr110 of the vibration that the vibration sensor 110 detects to detect water leakage.

[0059] As a result, the vibration sensor 110 does not detect vibrations at the resonant frequency of the holding member 300 and the resonant frequency of the cable 150 (the power cable 151 and the signal cable 152). Even if the holding member 300 and the cable 150 (the power cable 151 and the signal cable 152) vibrate relatively greatly at the resonant frequency, the vibration sensor 110 can generate vibration data D110 that can detect vibrations caused by water leakage from the large pipe 500 with high sensitivity (high S / N ratio).

[0060] The frequency range of vibrations detected by the vibration sensor 110 to detect water leakage is, for example, 1 Hz to 2 kHz. The resonant frequency f300 of the holding member 300 and the resonant frequency f150 of the cable 150 are, for example, frequencies higher than 2 kHz.

[0061] Furthermore, the resonant frequency f300 of the holding member 300 and the resonant frequency f150 of the cable 150 (the power cable 151 and the signal cable 152) are different from the resonant frequency f100 of the vibration sensor unit 100. This prevents the vibration sensor unit 100 from resonating with the holding member 300 or the cable 150, resulting in a decrease in the sensitivity of the vibration sensor 110.

[0062] One end of the holding member 300 is held by the inner wall of the large pipe 500 via a holder 510, and is held inside the large pipe 500. The holder 510 is fixed to the inner wall of the large pipe 500. The other end of the holding member 300 holds the vibration sensor unit housing 120 of the vibration sensor unit 100 inside the large pipe 500 (for example, the other end of the holding member 300 and the vibration sensor unit housing 120 are joined). Furthermore, the part of the holding member 300 that is not held by the holder 510 is disposed in a position that does not contact the inner wall of the large pipe 500, and the vibration sensor unit 100 is disposed in a position that does not contact the inner wall of the large pipe 500 so as to be submerged in the water W.

[0063] As described above, the arrangement of the holding member 300 and the vibration sensor unit 100 may be other than the arrangement shown in Figs. 4 and 5 in which the holding member 300 held at the top of the large pipe 500 holds the vibration sensor unit 100 inside the large pipe 500. The arrangement of the holding member 300 and the vibration sensor unit 100 can be changed. The arrangement of the holding member 300 and the vibration sensor unit 100 may be changed so long as the holding member 300 holds the vibration sensor unit 100 inside the large pipe 500 (pipe). For example, the orientation of the holding member 300 can be changed to be horizontal or diagonal. A holder 510 may be provided at a position other than the top of the large pipe 500, such as the side or bottom of the inner wall of the large pipe 500, and the holding member 300 held by the holder 510 at a position other than the top of the large pipe 500 may hold the vibration sensor unit 100 inside the large pipe 500.

[0064] The holding member 300 is formed in a shape that holds the vibration sensor unit 100 at a position that does not contact the inner wall of the large pipe 500, for a large pipe 500 with an inner diameter of 75 mm or more and 5000 mm or less. The holding member 300 may be formed to have a rigidity sufficient to prevent it from bending due to the water pressure or water flow in the large pipe (pipe) 500. The holding member 300 may be formed to have a flexibility sufficient to bend due to the water pressure or water flow in the large pipe (pipe) 500.

[0065] The holding member 300 can be formed, for example, in a rod, plate or tube shape from a rigid material such as metal, resin or ceramic so that it has enough rigidity to prevent bending due to the water pressure or water flow inside the large pipe (pipe) 500. By forming the holding member 300 to have rigidity in this manner, the vibration sensor unit 100 and the vibration sensor 110 are held in fixed positions inside the large pipe 500, so that the vibration sensor 110 can stably detect the vibration of the water inside the large pipe 500.

[0066] The holding member 300 may be formed of a wire or cable so as to have flexibility to the extent that it can be bent by the water pressure or water flow in the large pipe (pipe) 500, or may be formed in a rod, plate, or tube shape using a material such as a flexible resin such as polypropylene. The cable 150 may also serve as the holding member 300. In this way, by forming the holding member 300 to have flexibility, the holding member 300 can bend so that the resistance of the holding member 300 and the vibration sensor unit 100 to the water in the large pipe 500 is reduced when the flow rate of the water in the large pipe 500 increases. This allows the water in the large pipe 500 to flow more stably inside the large pipe 500 when the flow rate of the water in the large pipe 500 increases.

[0067] When the holding member 300 is formed to have a degree of flexibility that allows it to bend due to the water pressure or water flow in the large pipe (pipe) 500, it is necessary to select the material and shape of the holding member 300 so that the resonance frequency f300 of the holding member 300 deviates from the frequency fr110 of the vibration detected by the vibration sensor 110 to detect water leakage. Also, in order to increase the water resistance of the holding member 300, the holding member 300 may be coated with paint.

[0068] Various methods can be used to hold the holding member 300 and the holding fixture 510, and to hold the holding member 300 and the holding fixture 510 together, such as screwing using screws after drilling screw holes in the holding member 300 and the holding fixture 510, welding, brazing, soldering, riveting, caulking, shrink fitting / press fitting, adhesion, and adhesion using an adhesive. Furthermore, these various methods can also be combined for holding.

[0069] A buffer material 511 is disposed between one end side (the inner wall side of the large pipe 500) of the holding member 300 and the inner wall of the large pipe 500. The buffer material 511 is shaped like a sheet or a ring. The thickness of the buffer material 511 is, for example, several mm to about 1 cm. The buffer material 511 is made of a soft material such as rubber, elastomer, or foamed resin. Since the buffer material 511 is made of a soft material, vibrations from the surroundings of the large pipe 500 that are transmitted to the large pipe 500 are prevented from being transmitted from the large pipe 500 to the holding member 300. This makes it possible to prevent vibrations from the surroundings of the large pipe 500 that are transmitted to the large pipe 500 from being transmitted from the large pipe 500 to the vibration sensor unit 100 via the holding member 300. The vibration sensor 110 can detect vibrations caused by a leak in the large pipe 500, which are transmitted through the water W in the large pipe 500, with higher sensitivity (higher S / N ratio).

[0070] In the portion of the retaining member 300 that exists within the large pipe 500, in an orthogonal cross section perpendicular to the extension direction E of the retaining member 300, the length 300Dx (see FIG. 4) in the water flow direction X in which the water W in the large pipe 500 flows is greater than the length 300Dy (see FIG. 5) in the width direction Y perpendicular to the water flow direction X (length 300Dx in the water flow direction X > length 300Dy in the width direction Y). This makes it possible to ensure the strength of the retaining member 300 while reducing the resistance to the water W in the large pipe 500.

[0071] It should be noted that the cross-sectional shape of the holding member 300 can be appropriately changed. For example, the cross-sectional shape of the holding member 300 may be a polygon such as a rectangle, a star, a circle, or an ellipse.

[0072] The control device 200 is installed above the large pipe 500 with a base 242 in between.

[0073] Magnets 243 are embedded in pedestal 242 on the side facing large pipe 500. If large pipe 500 is made of a ferromagnetic material, pedestal 242 is detachably held to large pipe 500 by magnet 243.

[0074] It is not necessary to use the base 242. Also, the control device 200 may be installed near the ground (the control device 200 is buried at a depth of 1 m or less) so that the control device 200 and the wireless device 2 can easily communicate with each other.

[0075] <Effects of the Invention> As described above, the vibration sensor 110 is disposed inside the large pipe 500 by the holding member 300 so as to be submerged in the water W at a position not in contact with the inner wall of the large pipe 500. The large pipe 500 (e.g., with an inner diameter of about 75 mm to 5000 mm) has a thicker wall than a small pipe (e.g., with an inner diameter of about 8 mm to 25 mm). Since the large pipe 500 has a thicker wall, vibrations caused by water leakage from the large pipe 500 are smaller. Furthermore, vibrations caused by water leakage from the wall surface of the large pipe 500 are less likely to be transmitted through the wall surface of the large pipe 500. As a result, the strength of vibrations caused by water leakage traveling through the water W in the large pipe 500 at the center of the diameter surface of the large pipe 500 is generally greater than the strength of vibrations caused by water leakage traveling through the wall surface of the large pipe 500. Therefore, the vibration sensor 110 of the water leakage detection system 1, which detects vibrations caused by water leakage from the large pipe 500 underwater within the large pipe 500, can detect vibrations caused by water leakage from the large pipe with relatively high sensitivity.

[0076] Furthermore, when a vehicle passes over the large pipe 500, vibrations that become noise may be transmitted from the surroundings of the large pipe 500 into the large pipe 500. Because the vibration sensor 110 is installed underwater inside the large pipe 500, the strength of vibrations that become noise transmitted from the surroundings of the large pipe 500 through the water W inside the large pipe 500 to the vibration sensor 110 is reduced compared to when the vibration sensor 110 is installed on the outer periphery of the large pipe 500.

[0077] The above describes the case where the water leakage detection system 1 is installed in a large pipe 500. Even when the water leakage detection system 1 is installed in a pipe with an inner diameter of, for example, 75 mm or less, the vibration sensor 110 is similarly installed underwater in the pipe, so that the intensity of vibration that becomes noise and is transmitted from the surroundings of the pipe through the water W inside the pipe to the vibration sensor 110 is reduced compared to the case where the vibration sensor 110 is installed on the outer periphery of the pipe.

[0078] Therefore, in the water leakage detection system 1, the vibration sensor 110 is positioned so that it is submerged in the water W at a position that does not contact the inner wall of the large pipe (piping) 500, so that the vibration sensor 110 can generate vibration data D110 that can detect vibrations caused by a leak in the large pipe 500 that travels through the water within the large pipe (piping) 500 with higher sensitivity (higher S / N ratio).

[0079] Then, the control device 200 generates piping status data D200 capable of detecting leakage from the large pipe (pipe) 500 with higher sensitivity from the vibration data D110, and transmits the generated piping status data D200 to the water piping management server 3. This enables a user of the water piping management server 3 (including a user of the user terminal 4) to detect leakage from the large pipe 500 with higher sensitivity using the piping status data D200 stored in the water piping management server 3. Therefore, the leakage detection system 1 makes it easy to detect leakage from the large pipe (pipe) 500 with higher sensitivity.

[0080] Moreover, the vibration data D110 output from the vibration sensor 110 to the control device 200 is digital data. Generally, digital data is less susceptible to noise than analog data. Therefore, since the vibration data D110 is digital data that is less susceptible to noise, the control device 200 can acquire the vibration data D110, which is digital data that is less susceptible to noise, and transmit the piping condition data D200 generated from the acquired vibration data D110 to the water piping management server 3. This makes it possible to receive and analyze the piping condition data D200 transmitted from the control device 200 and reliably detect water leakage from the large piping 500 with high sensitivity.

[0081] The holding member 300 is formed in a shape that holds the vibration sensor unit 100 at a position that does not contact the inner wall of the large pipe 500, for the large pipe 500 with an inner diameter of 75 mm or more and 5000 mm or less. This makes it easy to attach the vibration sensor unit 100 at a position that does not contact the inner wall of the large pipe 500.

[0082] In addition, the resonant frequency of the holding member 300 and the resonant frequency of the cable 150 (the power cable 151 and the signal cable 152) are higher than the frequency within the frequency range of vibrations detected by the vibration sensor 110 to generate the vibration data D110. Therefore, the vibration sensor 110 does not detect vibrations at the resonant frequency of the holding member 300 and the cable 150. As a result, even if the holding member 300 and the cable 150 vibrate relatively greatly at the vibration of the resonant frequency, the vibration sensor 110 can generate vibration data D110 that can detect vibrations caused by leakage of the large pipe 500 with high sensitivity (high S / N ratio). Then, the control device 200 can generate piping status data D200 that can detect leakage of the large pipe 500 with high sensitivity from the vibration data D110 and transmit the generated piping status data D200 to the water pipe management server 3. This makes it possible to receive and analyze the piping status data D200 and detect leakage of the large pipe 500 with high sensitivity.

[0083] Furthermore, in an orthogonal cross section perpendicular to the extension direction E of the holding member 300, the portion of the holding member 300 present within the large pipe 500 has a length 300Dx (see FIG. 4) in the water flow direction X in which the water W within the large pipe 500 flows (see FIG. 5) that is greater than a length 300Dy (see FIG. 5) in the width direction Y perpendicular to the water flow direction X (length 300Dy in width direction Y > length 300Dx in water flow direction X). This makes it possible to ensure the strength of the holding member 300 while reducing the resistance to the water W within the large pipe 500. If the resistance of the holding member 300 to the water within the large pipe 500 were large, the supply of water by the large pipe 500 would be hindered due to the water resistance of the holding member 300.

[0084] Furthermore, since the resistance of the holding member 300 to the water W is small, it is possible to suppress vibration of the holding member 300 caused by the water W. This suppresses vibration transmitted from the holding member 300 to the vibration sensor unit 100. Thus, the vibration sensor 110 can detect vibrations caused by a leak in the large pipe 500 that travel through the water in the large pipe 500 with higher sensitivity (higher S / N ratio).

[0085] Furthermore, by using battery 250A as power supply 250, it can be built into control device 200. This eliminates the need to transmit power from above ground to control device 200 and vibration sensor 110 via a cable, making it easy to install control device 200 and vibration sensor 110 in large underground pipe 500. Battery 250A is a primary battery such as an alkaline battery, a rechargeable secondary battery such as a lithium ion secondary battery or a lead storage battery, or a battery such as a fuel cell.

[0086] Moreover, the control device 200 is installed outside the large pipe (pipe) 500, and has the wireless communication device 400 built in. The antenna 420 used by the control device 200 to transmit pipe condition data is built in the control device 200, and does not extend outside the control device 200. If the antenna 420 were to extend outside the control device 200, care must be taken to ensure that the antenna 420 is waterproof and not to cut the antenna 420. Therefore, by having the antenna 420 built in the control device 200, it becomes easy to install the control device 200 in the large pipe 500 that is underground.

[0087] Hereinafter, the water leakage detection systems 1 of Examples 2 to 10 will be described. Among the components of the water leakage detection systems 1 of Examples 2 to 10, those components that have substantially the same configurations and functions as the components of the water leakage detection system 1 described in Example 1 will be assigned the same reference numerals as the components of the water leakage detection system 1 of Example 1, and descriptions thereof will be omitted.

[0088] Moreover, in the water leakage detection systems 1 of Examples 2 to 10, similar to the water leakage detection system 1 of Example 1, an example is shown in which a holding member 300 held at an upper part of a large pipe 500 holds the vibration sensor unit 100 inside the large pipe 500. As in the water leakage detection system 1 of Example 1, the arrangement of the holding member 300 and the vibration sensor unit 100 in the water leakage detection systems 1 of Examples 2 to 10 can be changed. The arrangement of the holding member 300 and the vibration sensor unit 100 may be such that the holding member 300 holds the vibration sensor unit 100 inside the large pipe 500 (pipe). For example, the orientation of the holding member 300 can be changed to horizontal or diagonal. A holder 510 may be provided at a position other than the top of the large pipe 500, such as the side or bottom of the inner wall of the large pipe 500, and a holding member 300 held by the holder 510 at a position other than the top of the large pipe 500 may hold the vibration sensor unit 100 inside the large pipe 500. EXAMPLES

[0089] The water leakage detection system 1 of the second embodiment will be described with reference to Fig. 6. In the water leakage detection system 1 of the first embodiment, the cables 150 (power cable 151 and signal cable 152) are located outside the holding member 300. In the water leakage detection system 1 of the second embodiment, the cables 150 (power cable 151 and signal cable 152) are stored inside the holding member 300.

[0090] FIG. 6 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the second embodiment is installed, including a cross-sectional view in the extension direction of the large pipe 500. As shown in FIG. 6, the water leakage detection system 1 of the second embodiment includes a cylindrical holding member 300P as the holding member 300. The cable 150 (power cable 151 and signal cable 152) is housed inside the holding member 300P. Both ends of the holding member 300P are closed by the large pipe 500 and the connector 130. In other words, the holding member 300P has a cable introduction hole 300P1. The internal space of the holding member 300P is the cable introduction hole 300P1 that extends from the part held by the large pipe 500 to the part holding the vibration sensor unit 100. The cable 150 is inserted through the cable introduction hole 300P1 of the holding member 300P.

[0091] As a result, the cable 150 (the power cable 151 and the signal cable 152) is protected by the holding member 300P. Deterioration of the sheath of the cable 150 due to exposure of the cable 150 to the water W is suppressed. The vibration sensor 110 of the vibration sensor unit 100 can stably detect vibrations. Therefore, it is possible to more stably receive and analyze piping condition data and detect water leakage from the large piping 500 with high sensitivity.

[0092] The cross-sectional shape of the holding member 300P may be any shape as long as it is hollow. For example, the cross-sectional shape of the holding member 300P may be a polygon such as a rectangle, square, diamond, or triangle. The cross-sectional shape of the holding member 300P may be a curved shape such as an ellipse. The curved shape can reduce the resistance of the holding member 300P to the water W. EXAMPLES

[0093] Third embodiment The water leakage detection system 1 according to the third embodiment will be described with reference to FIG. FIG. 7 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the third embodiment is installed, including a cross-sectional view of a diameter surface of a large pipe 500.

[0094] The water leakage detection system 1 of the first embodiment includes one holding member 300. The water leakage detection system 1 of the third embodiment includes two (a plurality of) holding members 300. The two (a plurality of) holding members 300 hold one vibration sensor unit 100 inside the large pipe 500.

[0095] As described above, two (plural) holding members 300 hold one vibration sensor unit 100 inside the large pipe 500, so that the vibration sensor unit 100 is suppressed from vibrating due to the water flow in the large pipe 500. Therefore, after reducing the influence of vibration of the vibration sensor unit 100 due to the water flow in the large pipe 500, the vibration sensor 110 in the vibration sensor unit 100 can detect vibration caused by water leakage in the large pipe 500, which travels through the water W in the large pipe 500. As a result, the vibration sensor 110 can generate vibration data D110 that can detect vibration caused by water leakage in the large pipe 500 with higher sensitivity (high S / N ratio) that travels through the water in the large pipe 500. Then, the control device 200 can generate pipe status data D200 that can detect water leakage in the large pipe 500 with higher sensitivity from the vibration data D110, and transmit the generated pipe status data D200 to the water pipe management server 3. This makes it possible to receive and analyze the pipe condition data D200 and detect leakage from the large pipe 500 with high sensitivity. EXAMPLES

[0096] Fourth embodiment The water leakage detection system 1 according to the fourth embodiment will be described with reference to FIG. 8 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the fourth embodiment is installed, including a cross-sectional view of a diameter surface of the large pipe 500. In the water leakage detection system 1 of the fourth embodiment, the holding member 300A is formed by connecting two partial holding members 310A and 310B to each other. More specifically, the holding member 300A is formed by joining the partial holding member 310A on the large pipe 500 side and the partial holding member 310B on the vibration sensor unit 100 side by at least one screw 311.

[0097] The number of screws used to screw the partial holding member 310A and the partial holding member 310B together may be one. By using two or more screws to screw the partial holding member 310A and the partial holding member 310B together and screwing them at two or more locations with two or more screws 311, the connection state of the partial holding members 310A and 310B can be made stronger. This makes it possible to suppress vibrations occurring in the partial holding members 310A and 310B and the vibration sensor unit 100 due to the connection state of the partial holding members 310A and 310B. As a result, the vibration sensor 110 can detect vibrations caused by a water leak in the large pipe 500 that propagates through the water in the large pipe 500 with higher sensitivity (higher S / N ratio). In addition, the partial holding members 310A and 310B can be joined by various methods other than screw fastening, such as welding, brazing, soldering, riveting, caulking, shrink fitting / press fitting, adhesion, adhesion using an adhesive, etc. Furthermore, these various methods can also be combined for joining.

[0098] A buffer material 312 is provided between the partial holding member 310A and the partial holding member 310B. The buffer material 312 is formed in a sheet shape from a soft material such as rubber, elastomer, or foamed resin. Since the buffer material 312 is formed from a soft material, vibrations from the surroundings of the large pipe 500 that are transmitted from the large pipe 500 to the partial holding member 310A are prevented from being transmitted from the partial holding member 310A to the partial holding member 310B. This prevents vibrations from the surroundings of the large pipe 500 that are transmitted to the large pipe 500 from being transmitted to the vibration sensor unit 100 via the partial holding members 310A and 310B. As a result, the vibration sensor 110 can detect vibrations caused by water leakage from the large pipe 500 that travel through the water in the large pipe 500 with higher sensitivity (higher S / N ratio).

[0099] Furthermore, the number of partial holding members 310 constituting the holding member 300A is not limited to two, the partial holding members 310A and 310B, but may be two or more.

[0100] As described above, the holding member 300A is formed by connecting at least two partial holding members 310 (partial holding members 310A, 310B) to each other. When attaching the water leakage detection system 1 to each of various large pipes 500 with different inner diameters, a plurality of partial holding members 310 (partial holding members 310A or 310B) with different lengths are prepared, and the partial holding member 310 (partial holding member 310A or 310B) to be used is changed according to the inner diameter of the large pipe 500, so that the vibration sensor unit 100 can be attached to various large pipes 500 with different inner diameters. Here, what is needed to attach the water leakage detection system 1 to various large pipes 500 with different inner diameters is not the holding members 300 with various lengths, but the partial holding members 310 (partial holding members 310A or 310B) with various lengths that are lighter than the holding member 300.

[0101] Therefore, the total weight of the parts of the water leak detection system 1 required to attach the vibration sensor unit 100 to various large pipes 500 with different inner diameters is less when the partial holding members 310 (partial holding members 310A, 310B) are used than when an integrally formed holding member 300 is used. Therefore, since the holding member 300 is formed by connecting at least two partial holding members 310, the amount of raw materials of the water leak detection system 1 required to attach the water leak detection system 1 to various large pipes 500 with different inner diameters can be reduced. EXAMPLES

[0102] The water leakage detection system 1 of the fifth embodiment will be described with reference to FIGS. Fig. 9 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the fifth embodiment is installed, including a cross-sectional view of a diameter surface of a large pipe 500. Fig. 10 is a schematic explanatory diagram showing an example of a state in which the length of the holding member 300B of the water leakage detection system 1 of the fifth embodiment in Fig. 9 is changed.

[0103] In the water leakage detection system 1 of the fifth embodiment, the holding member 300B is formed by connecting two partial holding members 310C and 310D to each other. A plurality of screw holes 313 are provided in each of the two partial holding members 310C and 310D. The two partial holding members 310C and 310D are screwed together by two screw holes 313 and two screws 311 out of the plurality of screw holes 313 in each of the two partial holding members 310C and 310D. The screw holes 313 used for screwing can be changed as appropriate in each of the two partial holding members 310C and 310D. The length of the holding member 300B can be changed by changing the screw holes 313 used for screwing. For example, as shown in FIG. 9, the holding member 300B set to an appropriate length can be made longer as shown in FIG. 10. As a result, the length of the holding member 300B can be adjusted to an appropriate length by changing the screw holes into which the screws 311 are screwed as described above for various large pipes 500 with different inner diameters, and then the water leakage detection system 1 of Example 5 can be attached. Therefore, the water leakage detection system 1 of Example 5 can be easily attached to various large pipes 500 with different inner diameters.

[0104] The multiple screw holes 313 are multiple connecting parts 313 that connect at least two partial holding members 310C, 310D to each other. The holding member 300B is formed so that the length of the holding member 300B connecting at least two partial holding members 310C, 310D from one end side held by the large pipe 500 to the part holding the vibration sensor unit 100 can be changed by changing the combination of the connecting parts 313 used to connect at least two partial holding members 310C, 310D among the multiple connecting parts 313. This makes it easy to adjust the length of the holding member 300B. Therefore, the water leakage detection system 1 can easily attach the vibration sensor unit 100 to various large pipes 500 with different inner diameters.

[0105] Between the partial holding member 310C and the partial holding member 310D, there is a buffer material 312. The buffer material 312 has the same configuration and effect as the buffer material 312 of the fourth embodiment shown in Fig. 8, and therefore a description of the configuration and effect will be omitted.

[0106] As described above, the holding member 300B is formed by connecting at least two partial holding members 310 (partial holding members 310C, 310D) to each other. When attaching the water leakage detection system 1 to each of various large pipes 500 with different inner diameters, a plurality of partial holding members 310 (partial holding members 310C or 310D) with different lengths are prepared, and the partial holding member 310 (partial holding member 310C or 310D) to be used is changed according to the inner diameter of the large pipe 500, so that the vibration sensor unit 100 can be attached to various large pipes 500 with different inner diameters. Here, what is needed to attach the water leakage detection system 1 to various large pipes 500 with different inner diameters is not the holding members 300 with various lengths, but the partial holding members 310 (partial holding members 310C or 310D) with various lengths that are lighter than the holding member 300.

[0107] Therefore, the total weight of the parts of the water leak detection system 1 required to attach the vibration sensor unit 100 to various large pipes 500 with different inner diameters is less when the partial holding members 310 (partial holding members 310C, 310D) are used than when an integrally formed holding member 300 is used. Therefore, since the holding member 300 is formed by connecting at least two partial holding members 310, the amount of raw materials of the water leak detection system 1 required to attach the water leak detection system 1 to various large pipes 500 with different inner diameters can be reduced. EXAMPLES

[0108] A water leakage detection system 1 according to a sixth embodiment will be described with reference to FIG. FIG. 11 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the sixth embodiment is installed, including a cross-sectional view of the extension direction of the large pipe 500. In the water leakage detection system 1 of the sixth embodiment, the vibration sensor unit 100 has a vibration sensor unit housing 120 including a box body 121 and a lid body 122. That is, the vibration sensor unit housing 120 is formed by connecting a box-shaped box body 121 having an opening 121a on one end face side and a lid body 122 that covers the opening 121a on one end face side of the box body 121. A seal material 123 is sandwiched at the boundary between the box body 121 and the lid body 122. The seal material 123 waterproofs the boundary between the box body 121 and the lid body 122. The material of the seal material 123 is soft resin, rubber, metal, or the like.

[0109] The vibration sensor 110 is disposed inside the box 121 of the vibration sensor unit housing 120. The cover 122 of the vibration sensor unit housing 120 has a connector 130 to which a cable 150 is connected.

[0110] As described above, the vibration sensor unit housing 120 is formed by connecting a box-shaped box body 121 having an opening 121a on one end face side and a lid body 122 that covers the opening 121a on one end face side of the box body 121. When assembling the vibration sensor unit 100, an object to be placed inside the vibration sensor unit 100, such as the vibration sensor 110, is placed inside the box body 121 through the opening 121a of the box body 121, and further, the box body 121 and the lid body 122 are connected to each other to assemble the vibration sensor unit 100. Since the vibration sensor unit 100 can be assembled in this manner, the assembly of the vibration sensor unit 100 becomes easy. In FIG. 11, the shapes of the vibration sensor unit housing 120, the box body 121, and the lid body 122 are shown as squares, but the shape of the vibration sensor unit housing 120 may also be a sphere, a cylinder, or a cone, and the shapes of the box body 121 and the lid body 122 may be any shape that matches the shape of the vibration sensor unit housing 120.

[0111] Furthermore, since the vibration sensor unit 100 has the connector 130, it is possible to easily connect the cable 150 to the vibration sensor 110 while ensuring pressure resistance at the portion where the cable 150 is connected. Furthermore, since the connector 130 is provided on the cover 122 of the vibration sensor unit housing 120, it is possible to easily provide the connector 130 on the vibration sensor unit housing 120. Therefore, since the vibration sensor unit 100 has the connector 130, it is possible to both ensure pressure resistance at the portion where the cable 150 is connected and facilitate assembly of the vibration sensor unit 100. EXAMPLES

[0112] The water leakage detection system 1 of the seventh embodiment will be described with reference to FIG. FIG. 12 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the seventh embodiment is installed, including a cross-sectional view of the extension direction of the large pipe 500. In the water leakage detection system 1 of the seventh embodiment, the vibration sensor unit 100 has a vibration sensor unit housing 120 including a box body 121 and a lid body 122. The vibration sensor unit housing 120 is formed by connecting a box-shaped box body 121 having an opening 121b on one end face side (the inner wall side of the large pipe 500) and a lid body 122 that covers the opening 121b on one end face side (the inner wall side of the large pipe 500) of the box body 121. The opening 121b on one end side of the box body 121 of the vibration sensor unit housing 120 faces the one end side (the inner wall side of the large pipe 500) of the holding member 300 held by the large pipe (pipe) 500 in the vibration sensor unit housing 120.

[0113] A sealant 123 is sandwiched at the boundary between the box body 121 and the lid body 122. The boundary between the box body 121 and the lid body 122 is waterproofed by the sealant 123. The material of the sealant 123 is soft resin, rubber, metal, or the like.

[0114] The vibration sensor 110 is disposed inside the box 121 of the vibration sensor unit housing 120. The cover 122 of the vibration sensor unit housing 120 has a connector 130 to which a cable 150 is connected.

[0115] As described above, the vibration sensor unit housing 120 is formed by connecting a box-shaped box body 121 having an opening 121b on one end face side (the inner wall side of the large pipe 500) and a lid body 122 that covers the opening 121b on one end face side (the inner wall side of the large pipe 500). When assembling the vibration sensor unit 100, an object to be placed inside the vibration sensor unit 100, such as the vibration sensor 110, is placed inside the box body 121 through the opening 121b of the box body 121, and further connected to the box body 121 and the lid body 122 to assemble the vibration sensor unit 100. Since the vibration sensor unit 100 can be assembled in this manner, the assembly of the vibration sensor unit 100 becomes easy. In FIG. 12, the shapes of the vibration sensor unit housing 120, the box body 121, and the lid body 122 are shown as squares, but the shape of the vibration sensor unit housing 120 may also be a sphere, a cylinder, or a cone, and the shapes of the box body 121 and the lid body 122 may be any shape that matches the shape of the vibration sensor unit housing 120.

[0116] Furthermore, since the vibration sensor unit 100 has the connector 130, it is possible to easily connect the cable 150 to the vibration sensor 110 while ensuring pressure resistance at the portion where the cable 150 is connected. Furthermore, since the connector 130 is provided on the cover 122 of the vibration sensor unit housing 120, it is possible to easily provide the connector 130 on the vibration sensor unit housing 120. Therefore, since the vibration sensor unit 100 has the connector 130, it is possible to both ensure pressure resistance at the portion where the cable 150 is connected and facilitate assembly of the vibration sensor unit 100.

[0117] Moreover, the opening 121b at one end side (the inner wall side of the large pipe 500) of the box 121 of the vibration sensor unit housing 120 faces one end side (the holder 510 side) of the holding member 300 in the vibration sensor unit housing 120. Therefore, the part of the vibration sensor unit housing 120 closest to the one end side (the holder 510 side) of the holding member 300 is the upper surface of the lid 122. Therefore, in order to shorten the length of the cable 150 (the power cable 151 and the signal cable 152) inside the large pipe (pipe) 500, it is necessary to provide the connector 130 on the upper surface of the lid 122 and connect the cable 150 (the power cable 151 and the signal cable 152) to the connector 130.

[0118] Also, holes can be drilled more easily in the top surface of the lid 122 than in the side surface. Therefore, it is easier to provide the connector 130 on the top surface of the lid 122 than on the side surface of the lid 122. That is, it is easier to provide the connector 130 on the top surface of the lid 122 (the portion covering the opening 121b of the box 121). This makes it easier to provide the connector 130 on the top surface of the lid 122 (the portion covering the opening 121b of the box 121) so as to shorten the length of the cables 150 (power cable 151 and signal cable 152) inside the large piping (piping) 500.

[0119] As described above, the opening 121b on one end side (the inner wall side of the large pipe 500) of the box 121 of the vibration sensor unit housing 120 faces one end side (the holder 510 side) of the holding member 300 in the vibration sensor unit housing 120. As a result, it becomes easy to provide the connector 130 on the cover 122 (the part covering the opening 121b of the box 121) so as to shorten the length of the cable 150 (the power cable 151 and the signal cable 152) inside the large pipe (pipe) 500. EXAMPLES

[0120] The water leakage detection system 1 of the eighth embodiment will be described with reference to FIG. FIG. 13 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the eighth embodiment is installed, including a cross-sectional view of the extension direction of the large pipe 500. In the water leakage detection system 1 of the eighth embodiment, a vibration sensor element 112 is used as the vibration sensor 110. The vibration sensor element 112 (vibration sensor 110) is mounted on a vibration sensor board 111 arranged in a vibration sensor unit housing 120. In other words, the vibration sensor 110 is provided on the vibration sensor board 111. The vibration sensor element 112 is, for example, a vibration sensor in the shape of a semiconductor package. The vibration sensor element 112 is, for example, a capacitive vibration sensor, a piezoelectric vibration sensor, or an electrodynamic vibration sensor made by MEMS (Micro Electro Mechanical Systems) technology.

[0121] An electric circuit 113 is formed on the vibration sensor board 111, and the cable 150 (power cable 151 and signal cable 152) is electrically connected to the vibration sensor board 111. In other words, the control device 200 and the vibration sensor 110 are electrically connected via a signal cable (cable) 152, and the vibration sensor board 111 has an electric circuit 113 that electrically connects the vibration sensor 110 and the signal cable (cable) 152. In addition, the vibration sensor element 112 is supplied with power from the vibration sensor board 111 via the electric circuit 113. In this way, since the vibration sensor board 111 has the electric circuit 113 that electrically connects the vibration sensor 110 and the signal cable (cable) 152, it becomes easy to electrically connect the vibration sensor 110 and the signal cable (cable) 152.

[0122] As described above, by using the vibration sensor element 112 arranged on the vibration sensor board 111 as the vibration sensor 110, the vibration sensor 110 can be easily installed in the vibration sensor unit housing 120. Furthermore, by mounting the vibration sensor element 112 on the vibration sensor board 111 arranged on the vibration sensor unit housing 120, it becomes easy to ensure the sensitivity of the vibration sensor 110 (vibration sensor element 112). EXAMPLES

[0123] The water leakage detection system 1 of the ninth embodiment will be described with reference to Fig. 14 and Fig. 15. Fig. 14 is a schematic explanatory diagram showing an example of a state in which the water leakage detection system 1 of the ninth embodiment is installed, including a cross-sectional view in the extension direction of a large pipe 500. Fig. 15 is a block diagram showing an example of a functional block diagram of the water leakage detection system 1 of the ninth embodiment.

[0124] As shown in Fig. 14, in the water leakage detection system 1 of the ninth embodiment, the control device 200A and the vibration sensor 110 are provided in a vibration sensor unit housing 120. As shown in Fig. 15, the control device 200A has a processing unit 210 (signal processing unit 212 and vibration data recording unit 211) and a memory unit 220 (vibration data log 221, vibration analysis result data log 222, etc.) like the control device 200 (see Fig. 2). Also, as shown in Fig. 14, the control device housing 240 located outside the large pipe 500 does not include the control device 200, but instead includes a wireless communication device 400 and a power source 250.

[0125] The control device 200A of the water leakage detection system 1 of the ninth embodiment has the same functional units as the control device 200 of the first embodiment (see FIG. 2) as shown in FIG. 15. The control device 200A of the ninth embodiment has the same hardware resources as the control device 200 of the first embodiment. The water leakage detection system 1 of the ninth embodiment differs from the water leakage detection system 1 of the first embodiment in the following points. 1. In the ninth embodiment, the piping condition data D200 generated by the control device 200A is transmitted from the control device 200A inside the vibration sensor unit housing 120 to the wireless communication device 400 inside the control device housing 240. 2. The control device 200A receives power from a power supply 250 in the control device housing 240 via a power cable 151. 3. The signal cable 152 in the ninth embodiment is used for transmitting piping condition data, unlike the first embodiment. The piping condition data D200 is digital data.

[0126] The amount of data of the pipe condition data D200 is usually smaller than that of the vibration data D110. Therefore, the amount of data transmitted by the signal cable 152 in the water leakage detection system 1 of the ninth embodiment is smaller than that of the vibration data D110 transmitted by the signal cable 152 in the first embodiment. This allows the power consumption of the control device 200A to be reduced, and when the power source 250 is a battery 250A, the battery 250A lasts longer. Furthermore, since the amount of data of the pipe condition data D200 is smaller than that of the vibration data D110, the deterioration of data occurring during the data transmission of the signal cable 152 is smaller in the water leakage detection system 1 of the ninth embodiment than in the water leakage detection system 1 of the first embodiment. This makes it possible to receive and analyze the pipe condition data D200 and detect the leakage of the large pipe 500 with higher reliability and sensitivity. The water leakage detection system 1 makes it easier to detect the leakage of the large pipe 500 with higher reliability and sensitivity.

[0127] The signal processing unit 212 of the ninth embodiment may compile a plurality of pieces of piping condition data D200 and transmit them to the wireless communication device 400. The signal processing unit 212 of the ninth embodiment may compile a plurality of pieces of piping condition data D200, further compress them, and transmit them to the wireless communication device 400. This reduces the amount of data transmitted through the signal cable 152, thereby saving power to the control device 200A and suppressing data degradation that occurs in the process of transmitting data through the signal cable 152.

[0128] In addition, since the control device 200A is located near the vibration sensor 110, the vibration data D110 stored in the vibration data log 221 has less noise, and the piping condition data D200 stored in the vibration analysis result data log 222 has less noise than the water leakage detection system 1 of the first embodiment. Note that an electromagnetic shield 201 (see Figs. 14 and 15) is provided between the control device 200A and the vibration sensor 110. EXAMPLES

[0129] The water leakage detection system 1 of the tenth embodiment will be described with reference to Fig. 16. Fig. 16 is a block diagram showing an example of a functional block diagram of the water leakage detection system 1 of the tenth embodiment.

[0130] As shown in FIG. 16, in the water leakage detection system 1 of the tenth embodiment, the control device 200B and the vibration sensor 110 are provided in the vibration sensor unit housing 120, as in the ninth embodiment. Also, in the water leakage detection system 1 of the tenth embodiment, the control device housing 240 outside the large pipe 500 does not include the control device 200, but includes the wireless communication device 400 and the power source 250, as in the water leakage detection system 1 of the ninth embodiment. As shown in FIG. 16, the control device 200B does not include the signal processing unit 212 of the processing unit 210 and the vibration analysis result data log 222 of the storage unit 220, unlike the control device 200 (see FIG. 2) and the control device 200A (see FIG. 15) of the first embodiment. In the tenth embodiment, the signal processing is omitted, and the vibration data D110 is used as the pipe condition data D200.

[0131] Furthermore, since the control device 200B is located near the vibration sensor 110, the vibration data D110 stored in the vibration data log 221 contains less noise than the water leakage detection system 1 of the first embodiment.

[0132] The present invention is not limited to the above-mentioned embodiment, but includes various modified examples. For example, the above-mentioned embodiment describes the configuration in detail to easily explain the present invention, and the present invention is not necessarily limited to the configuration including all the described configurations. Also, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration. [Explanation of symbols]

[0133] 1000: Water piping management system, 1: Water leakage detection system, 2: Wireless device, 3: Water piping management server, 4: User terminal, NW: Network, 100: vibration sensor unit, 110: vibration sensor, 111: vibration sensor board, 112: vibration sensor element, 113: electric circuit, 120: vibration sensor unit housing, 120x: internal space, 121: box body, 121a, 121b: openings, 122: lid body, 123: sealing material, 130: connector, 150: cable, 151: power cable, 152: signal cable, 200:, 200A, 200B: control device, 201: shield, 210: processing unit, 211: vibration data recording unit, 212: signal processing unit, 220: memory unit, 221: vibration data log, 222: vibration analysis result data log, 240: control device housing, 241: connector, 242: base, 243: magnet, 250, 250A: Power supply (battery) 300, 300A, 300B, 300P: holding member, 300P1: cable introduction hole, 310A, 310B, 310C, 310D: partial holding member, 311: screw, 312: cushioning material, 313: screw hole (connection part), 400: wireless communication device, 410: communication circuit, 420: antenna, 500: Large piping (piping), 501: Water leak point, 510: Holder, 511: Cushioning material, D110: Vibration data, D200: Pipe condition data, D201: Transmission data, D202: Transmission data, D300: Information on water leakage, W:Water, X: water flow direction, Y: width direction, E: elongation direction.

Claims

1. A water leak detection system, comprising: The device includes a vibration sensor unit, a control device, a wireless communication device, a power source, and a holding member. The vibration sensor unit has a vibration sensor that detects vibrations in water in a water pipe and generates vibration data, and is disposed so as to be submerged in water at a position not in contact with an inner wall of the water pipe; The wireless communication device is capable of wirelessly transmitting and receiving data; The power source supplies power to the vibration sensor unit, the control device, and the wireless communication device; The control device includes: a vibration sensor, a wireless communication device, and a power source; acquiring the vibration data from the vibration sensor; generating pipe condition data including information on a state of the pipe based on the acquired vibration data; causing the wireless communication device to generate transmission data including the generated piping status data, and further causing the wireless communication device to transmit the generated transmission data to a water piping management server; The holding member is held by the pipe at one end side inside the pipe and holds the vibration sensor unit at a position not in contact with an inner wall of the pipe. Leak detection system.

2. 2. The water leak detection system according to claim 1, The vibration data generated by the vibration sensor is digital data. Leak detection system.

3. 2. The water leak detection system according to claim 1, The holding member is formed in a shape for holding the vibration sensor unit at a position not in contact with an inner wall of a large pipe having an inner diameter of 75 mm or more and 5000 mm or less. Leak detection system.

4. 2. The water leak detection system according to claim 1, the control device and the vibration sensor are electrically connected via a cable; a resonant frequency of the holding member and a resonant frequency of the cable are higher than a frequency of vibration detected by the vibration sensor to generate vibration data; Leak detection system.

5. 2. The water leak detection system according to claim 1, In a cross section perpendicular to the extension direction of the holding member, the length of the portion of the holding member present in the pipe in the water flow direction in which the water in the pipe flows is longer than the length in the width direction perpendicular to the water flow direction. Leak detection system.

6. 2. The water leak detection system according to claim 1, The power source is a battery. Leak detection system.

7. 2. The water leak detection system according to claim 1, The control device is installed outside the piping and has the wireless communication device built therein. Leak detection system.

8. 2. The water leak detection system according to claim 1, A plurality of the holding members are provided, A plurality of the holding members hold one of the vibration sensor units inside the piping. Leak detection system.

9. 2. The water leak detection system according to claim 1, The holding member is formed by connecting at least two partial holding members to each other. Leak detection system.

10. 10. The water leak detection system according to claim 9, At least two of the partial holding members have a plurality of connecting portions that connect to each other, The holding member is formed so that a length of the holding member connecting at least two of the partial holding members from the one end side held by the piping to a portion holding the vibration sensor unit can be changed by changing a combination of the connecting parts used to connect at least two of the partial holding members among the plurality of connecting parts. Leak detection system.

11. 2. The water leak detection system according to claim 1, The vibration sensor unit has a vibration sensor unit housing, The vibration sensor unit housing is formed by connecting a box-shaped box body having an opening on one end surface side and a lid body covering the opening on the one end surface side of the box body. Leak detection system.

12. 12. The water leak detection system according to claim 11, The control device and the vibration sensor are electrically connected via a cable, The box body of the vibration sensor unit housing accommodates the vibration sensor therein, The cover of the vibration sensor unit housing has a connector for connecting the cable. Leak detection system.

13. 13. The water leak detection system of claim 12, The opening at the one end side of the box body of the vibration sensor unit housing faces the one end side of the holding member in the vibration sensor unit housing. Leak detection system.

14. 2. The water leak detection system according to claim 1, the control device and the vibration sensor are electrically connected via a cable; the holding member has a cable introduction hole extending from a portion held by the piping to a portion holding the vibration sensor unit, The cable is inserted through the cable introduction hole of the holding member. Leak detection system.

15. 2. The water leak detection system according to claim 1, The vibration sensor unit further includes a vibration sensor unit housing and a vibration sensor substrate provided inside the vibration sensor unit housing, The vibration sensor is provided on the vibration sensor substrate. Leak detection system.

16. 16. The water leak detection system of claim 15, the control device and the vibration sensor are electrically connected via a cable; The vibration sensor board has an electric circuit that electrically connects the vibration sensor and the cable. Leak detection system.

17. 17. The water leak detection system of claim 16, The electric circuit is provided with a signal processing unit that processes the vibration data of the vibration sensor, and a storage unit that stores the vibration data processed by the signal processing unit and the vibration data. Leak detection system.

18. 2. The water leak detection system according to claim 1, The vibration sensor unit has a vibration sensor unit housing, The control device is provided in the vibration sensor unit housing. Leak detection system.

19. 2. The water leak detection system according to claim 1, The holding member has a rigidity sufficient to prevent bending due to water pressure or water flow in the piping. Leak detection system.

20. 2. The water leak detection system according to claim 1, The holding member has a degree of flexibility such that it can be bent by the water pressure or water flow in the piping. Leak detection system.

Images