JP6971948B2 - Leakage detector - Google Patents

Description

The present invention relates to the structure of a liquid leakage detection device, particularly the structure of a liquid leakage detection device using a constant voltage element.

As a method of detecting the occurrence of liquid leakage from air conditioning equipment, etc., when a current is passed through a liquid leakage detection band in which two conductors are arranged in parallel in a non-conducting state, and liquid leaks enter between the two conductors. A method of detecting liquid leakage by detecting a short circuit is used.

However, with such a leak detection method, although the leak can be detected, the location where the leak occurs cannot be detected. Therefore, a method of identifying the leak location by using a leak sensor in which three electrode wires insulated so as to allow liquid to pass through are arranged in parallel and the resistance values per unit length of the two electrode wires are different. Have been proposed (see, for example, Patent Documents 1 and 2).

On the other hand, liquid leakage monitoring may target not only a partitioned plane such as under the floor of a server room but also a complicated shape having a large number of spatial branches such as an air conditioning pipe. In the conventional liquid leakage detection method as described in Patent Documents 1 and 2, since the liquid leakage location is specified based on the resistance value per unit length of the electrode wire, the liquid leakage is matched to the shape of the pipe. It is difficult to branch the sensor. Therefore, an electrode wire is arranged for each branch, each electrode wire and the detector are connected by an electric wire via a changeover switch, and the changeover switch switches the connection between the detector and each electrode wire to detect leakage. A method has been proposed (see, for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 8-271461 Special Fair 2-43130 Gazette Special Fair 7-119664 Gazette

However, in the conventional technique as described in Patent Document 3, there is a problem that the number of electric wires arranged for each branch and connecting between each electrode wire and the detector increases, and the structure becomes complicated. was there.

Therefore, it is an object of the present invention to enable leakage monitoring of an object having a complicated shape with a simple configuration.

The liquid leakage detection device of the present invention is composed of a pair of conductive wires, and is connected to and applied to a liquid leakage detection band including a detection region in which a current flows when a leak comes into contact between the conductive wires and a liquid leakage detection band. A trunk liquid detection unit in which one or a plurality of liquid leakage detection units including a node having a constant voltage element that conducts when a voltage reaches a predetermined voltage value is connected in series, and one of the liquid leakage detection units. Alternatively, a branch leakage detection unit in which a plurality of the branch leakage detection units are connected in series, a power supply connected to the start end of the trunk leakage detection unit, and a current detection unit that detects an input current value at the start end of the trunk leakage detection unit. A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided, and the branch start end of the branch leakage detection unit is one or more of the trunk leakage detection units. It is connected to the leak detection unit of the above, and each of the leak detection units has a characteristic of conducting current according to an input voltage value, and the power supply outputs a voltage corresponding to a voltage command value input from the determination unit. Then, the determination unit fluctuates the voltage command value output to the power supply before and after the standby voltage value, and fluctuates the input voltage value of the trunk leakage detection unit before and after the standby voltage value, and causes the voltage. By comparing the conductance or resistance value calculated from the command value or the input voltage value and the input current value detected by the current detection unit with a predetermined threshold value, leakage occurs in at least one of the leak detection units. It rukoto is determined that the liquid has occurred, characterized by.

In a leak detection device that includes a trunk leak detection unit and a branch leakage detection unit, each of which has a leakage detection unit, the input voltage value of the trunk leakage detection unit is changed before and after the standby voltage value using a common power supply. , Leakage in the leak detection unit by comparing the conductance or resistance value calculated from the voltage command value or input voltage value in the common judgment unit and the input current value detected in the current detection unit with a predetermined threshold value. Can be determined to have occurred. This makes it possible to monitor the leakage of an object having a complicated shape including branching with a simple configuration.

In the liquid leakage detection device of the present invention, the node of the liquid leakage detection unit has a pair of start end side terminals, a pair of end side terminals to which the pair of conductive wires are connected, and a start end side terminal and an end side terminal. The constant voltage element may be arranged so as to be interposed between any one or both of the connection lines, including a pair of connection lines connecting the two in parallel.

In this way, since the arrangement of the constant voltage element of the node can be variously changed according to the liquid to be detected, it is possible to detect the leak according to the liquid to be detected.

The liquid leakage detection device of the present invention is composed of a pair of conductive wires, and is connected to and applied to a liquid leakage detection band including a detection region in which a current flows when a leak comes into contact between the conductive wires and a liquid leakage detection band. A trunk liquid detection unit in which one or a plurality of liquid leakage detection units including a node having a constant voltage element that conducts when a voltage reaches a predetermined voltage value is connected in series, and one of the liquid leakage detection units. Alternatively, a branch leakage detection unit in which a plurality of units are connected in series, a power supply connected to the start end of the trunk leakage detection unit, and a current detection unit that detects an input current value at the start end of the trunk leakage detection unit. A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided, and the branch start end of the branch leakage detection unit is one or more of the trunk leakage detection units. Each of the leak detection units is connected to the leak detection unit and has a characteristic that each of the leak detection units conducts according to an input voltage value, and each of the leak detection units is connected in series from the start end to the leak detection unit. The unit numbers are assigned in ascending order of the integrated voltage value of the energization voltage value of each constant voltage element included in each of the leak detection units, and the power supply is set to the voltage command value input from the determination unit. The corresponding voltage is output, and the determination unit sweeps the voltage command value output to the power supply to sweep the input voltage value of the trunk leakage detection unit, and sets each of the leakage detection units as a unit number. By comparing the voltage command value or the input voltage value with the conduction or resistance value calculated from the input current value detected by the current detector and a predetermined threshold value, the unit number in the conduction state It is characterized in that it is determined that a leak has occurred in the leak detection unit having at least one unit number among the leak detection units.

In the leak detection device including the trunk leak detection unit and the branch leak detection unit, each of which has a leak detection unit, each leak detection unit is assigned a unit number in this way, and the trunk leak is supplied by a common power supply. The input voltage value of the detector is swept, each leak detection unit is made conductive in the order of the unit number, and it is calculated from the voltage command value or input voltage value in the common judgment unit and the input current value detected by the current detector. By comparing the conductance or resistance value with a predetermined threshold value, it can be determined that a leak has occurred in the leak detection unit having at least one unit number among the leak detection units having a unit number in a conducting state. With a simple configuration, it is possible to monitor the leakage of an object with a complicated shape including branching.

The liquid leakage detection device of the present invention is composed of a pair of conductive wires, and is connected to and applied to a liquid leakage detection band including a detection region in which a current flows when a leak comes into contact between the conductive wires and a liquid leakage detection band. A trunk liquid detection unit in which one or more of the liquid leakage detection units including a node having a constant voltage element that conducts when the voltage reaches a predetermined voltage value and a plurality of them are connected in series, and one of the liquid leakage detection units. Alternatively, a branch leakage detection unit in which a plurality of the branch leakage detection units are connected in series, a power supply connected to the start end of the trunk leakage detection unit, and a current detection unit that detects an input current value at the start end of the trunk leakage detection unit. A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided, and the branch start end of the branch leakage detection unit is one or more of the trunk leakage detection units. Each of the leak detection units is connected to the leak detection unit and has a characteristic that each of the leak detection units conducts according to an input voltage value, and each of the leak detection units is connected in series from the start end to the leak detection unit. The unit numbers are assigned in ascending order of the integrated voltage value of the energization voltage value of each constant voltage element included in each of the leak detection units, and the power supply is set to the voltage command value input from the determination unit. The corresponding voltage is output, and the determination unit sweeps the voltage command value output to the power supply to sweep the input voltage value of the trunk leakage detection unit, and sets each of the leakage detection units as a unit number. The input current value detected by the current detection unit and the range when the range from the start end of the trunk leakage detection unit to the leakage detection unit of one unit number is brought into a conduction state. Among them, the leak detection unit having one unit number is used with the input current value detected by the current detection unit when the range other than the leak detection unit of one unit number is made conductive. By calculating the conductance of the above and comparing the calculated conductance with a predetermined threshold value, the unit number of the leak detection unit in which the leak has occurred is specified .

In a leak detection device including a trunk leak detection unit and a branch leak detection unit, each of which has a leakage detection unit, each leak detection unit is thus assigned a unit number and input to the trunk leakage detection unit. Leakage by sweeping the voltage value, conducting each leak detection unit in the order of unit number, calculating the conductance of the leak detection unit with one unit number, and comparing the calculated conductance with a predetermined threshold. It is possible to specify the unit number of the leak detection unit in which the liquid is generated. This makes it possible to identify the region where the leak has occurred when the leak occurs in an object having a complicated shape including branching or the like with a simple configuration.

In the leak detection device of the present invention, each leak detection unit has a current voltage value of each constant voltage element included in each leak detection unit connected in series from the start end to the leak detection unit. The integrated voltage values are all different, and unit numbers are assigned in ascending order of the integrated voltage values. The determination unit is at least one of the leak detecting units in a conductive state. It may be determined that a liquid leak has occurred.

In this way, since all the leak detection units are assigned different unit numbers, the occurrence of leaks can be determined for each leak detection unit by determining the occurrence of leaks for each unit number. Therefore, it can be determined that a leak has occurred in at least one leak detection unit.

In the leak detection device of the present invention, each leak detection unit has an integrated voltage value of the energization voltage value of each constant voltage element included in each leak detection unit connected in series from the start end to the leak detection unit. All are different, and the unit numbers are assigned in ascending order of the integrated voltage value, and the determination unit may specify the leak detection unit in which the leak has occurred.

In this way, since all the leak detection units are assigned different unit numbers, the occurrence of leaks can be determined for each leak detection unit by determining the occurrence of leaks for each unit number. Therefore, it is possible to identify the leak detection unit in which the leak has occurred.

In the leak detection device of the present invention, the branch start end of the branch leak detection unit is connected to the connection point between the branch start end and the leak detection unit of one of the stem leak detection units, and the end side of the connection point. A trunk switch provided between the other leakage detection unit of the trunk leakage detection unit and a branch switch provided between the connection point and the branch start end of the branch leakage detection unit. You may have it. Further, the determination unit determines whether the location where the leakage occurs is located in the trunk leakage detection unit or the branch leakage detection unit by switching between the trunk switch and the branch switch. You may.

With this configuration, when the occurrence of leak is detected by the leak detection device including the trunk leak detection unit and the branch leak detection unit, each of which has a leak detection unit, the location where the leak occurs is the trunk leak. Since it is possible to determine whether it is located in the liquid detection unit or the branch leak detection unit, it is possible to narrow down the area where the leak has occurred with a simple configuration.

In the liquid leakage detection device of the present invention, the liquid leakage detection band includes a non-detection region which is composed of a pair of covered electric wires and no current flows even if a liquid leaks between them, and the liquid leakage detection is performed. The node of the unit has a pair of start-side terminals, a pair of end-side terminals to which the pair of conductive wires are connected directly or via a pair of covered electric wires, and a start-end side terminal and a end-side terminal in parallel. The constant voltage element may be arranged so as to be interposed between one or both of the connection lines, including a pair of connection lines to be connected.

In this way, it is possible to reduce the cost by forming the portion that does not require monitoring of leakage with an inexpensive coated electric wire and shortening the length of the conductive wire.

In the leak detection device of the present invention, the branch start end of the branch leak detection unit is connected to the leak detection unit of the trunk leak detection unit via a pair of branch lines, and the pair of branch lines is connected to the branch line. In the meantime, it may be composed of a pair of the conductive wires through which an electric current flows when a leak comes into contact with the liquid.

With this configuration, it is possible to detect the occurrence of liquid leakage between the liquid leakage detection unit of the trunk liquid leakage detection unit and the branch start end of the branch liquid leakage detection unit.

In the leak detection device of the present invention, the branch start end of the branch leak detection unit is connected to the leak detection unit of the trunk leak detection unit via a pair of branch lines, and the pair of branch lines is connected to the branch line. , It may be composed of a pair of covered electric wires in which a current does not flow even if a leak comes into contact between them. Further, a part of the pair of branch wires is composed of a pair of conductive wires to which a current flows when a leak comes into contact between them, and a pair of coatings in which a current does not flow even if a leak comes into contact between the other portions. It may be composed of electric wires.

With this configuration, it is possible to shorten the length of the conductive wire by constructing a portion of the branch wire that does not require monitoring of liquid leakage with an inexpensive coated conductor wire, so that cost reduction can be achieved.

In the leak detection device of the present invention, between the leak detection units connected in series with the trunk leak detection unit, or between the leak detection units connected in series with the branch leak detection unit. In the repeater, the voltage value of the output terminal is set to a predetermined magnification of the voltage value of the input terminal, and the current value of the input terminal and the current value of the output terminal are the same. It may be held in.

With this configuration, the number of nodes that can be connected to the stem leak detection unit and the branch leakage detection unit can be increased. As a result, the lengths of the stem leakage detection unit and the branch leakage detection unit can be lengthened, and leakage can be detected in a wider range. In addition, the length of each unit can be shortened to detect leaks in a narrower range.

The liquid leakage detection device of the present invention is composed of a pair of conductive wires, and is connected to and applied to a liquid leakage detection band including a detection region in which a current flows when a leak comes into contact between the conductive wires and a liquid leakage detection band. A leak detection unit in which one or a plurality of leakage detection units including a node having a constant voltage element that conducts when the voltage reaches a predetermined voltage value is connected in series, and a start end of the leakage detection unit are connected. The power supply is provided, a current detection unit that detects the input current value at the start end of the liquid leakage detection unit, and a determination unit that determines the occurrence of liquid leakage from the input current value detected by the current detection unit. The one or a plurality of the leak detection units are composed of a pair of the conductive wires, and include a branch detection zone including a detection region in which a current flows when a leak comes into contact between the conductive wires, and the branch detection is performed. The band is connected to the leak detection band or the node, and has a characteristic that each leak detection unit conducts according to an input voltage value, and the determination unit detects the current detection unit. The occurrence of liquid leakage is determined from the input current value, and the node of the liquid leakage detection unit has a pair of start end side terminals, a pair of end side terminals to which the pair of conductive wires are connected, and the start end side terminal. The constant voltage element is arranged so as to be interposed between one or both of the connection lines, including a pair of connection lines for connecting the terminal and the terminal in parallel, and the power supply is the determination unit. The determination unit outputs the voltage corresponding to the voltage command value input from, and the determination unit changes the voltage command value output to the power supply before and after the standby voltage value to obtain the input voltage value of the liquid leakage detection unit. The conduction or resistance value calculated from the voltage command value or the input voltage value and the input current value detected by the current detection unit, which is varied before and after the standby voltage value, is compared with a predetermined threshold value. The present invention is characterized in that it is determined that a leak has occurred in at least one of the leak detection units.

With this configuration, it is possible to detect leaks such as branches of short pipes with one leak detection unit, and it is possible to monitor leaks of objects with complicated shapes including branches with a simple configuration. It will be possible. In addition, the conductance or resistance value is calculated by fluctuating the input voltage value of the liquid leakage detection unit before and after the standby voltage value, and the leakage is determined by this. Therefore, the leakage is determined by a physical quantity different from the input current value. It can be performed.

In the liquid leakage detection device of the present invention, the liquid leakage detection band includes a non-detection region which is composed of a pair of covered electric wires and no current flows even if a liquid leaks between them, and the liquid leakage detection. The terminal terminals of the node of the unit may be connected to each other by a pair of the conductive wires directly or via a pair of covered electric wires. Further, the branch detection band may include a non-detection region which is composed of a pair of covered electric wires and in which a current does not flow even if a leak comes into contact between them.

As a result, the length of the conductive wire can be shortened by forming the portion that does not require monitoring of the leak with an inexpensive coated conductor wire, so that the cost can be reduced.

The liquid leakage detection device of the present invention is composed of a pair of conductive wires, and is connected to and applied to a liquid leakage detection band including a detection region in which a current flows when a leak comes into contact between the conductive wires and a liquid leakage detection band. A leak detection unit in which one or more of the leakage detection units including a node having a constant voltage element that conducts when the voltage reaches a predetermined voltage value is connected in series, and a start end of the leakage detection unit are connected. The power supply is provided, a current detection unit for detecting the input current value at the starting end of the liquid leakage detection unit, and a determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit. A leak detection device including a repeater interposed between the leak detection units connected in series with the leak detection unit, and the repeater inputs a voltage value of an output terminal. A predetermined magnification of the voltage value of the terminal is set, and the current value of the input terminal and the current value of the output terminal are kept the same. The determination unit has a property of conducting, and the determination unit determines the occurrence of liquid leakage from the input current value detected by the current detection unit, and the node of the liquid leakage detection unit has a pair of start end side terminals and a pair. The constant voltage element includes a pair of terminal-side terminals to which the conductive wires of the above are connected, and a pair of connection wires for connecting the start-end side terminal and the terminal-side terminal in parallel. It is characterized in that it is arranged so as to intervene between both connecting lines.

By providing the repeater in this way, the number of liquid leakage detection units that can be connected to the liquid leakage detection unit can be increased. As a result, a long leak detection unit can be configured to detect leaks in a wider range. Further, it is possible to connect a large number of short-length leak detection units U to form a leak detection unit, narrow the identifiable leak range, and perform finer leak monitoring.

In the liquid leakage detection device of the present invention, the liquid leakage detection band includes a non-detection region which is composed of a pair of covered electric wires and no current flows even if a liquid leaks between them, and the liquid leakage detection. The terminal terminals of the node of the unit may be connected to each other by a pair of the conductive wires directly or via a pair of covered electric wires.

As a result, the length of the conductive wire can be shortened by forming the portion that does not require monitoring of the leak with an inexpensive coated conductor wire, so that the cost can be reduced.

In the liquid leakage detection device of the present invention, the power supply applies a standby voltage of a predetermined voltage value to the start end of the liquid leakage detection unit, and the determination unit has the input current value detected by the current detection unit. , The occurrence of leakage in at least one leakage detection unit may be determined by comparing with a predetermined threshold value.

As described above, with a simple configuration in which the standby voltage value is set to a predetermined voltage value, it is possible to determine the occurrence of liquid leakage in a short time.

In the liquid leakage detection device of the present invention, the power supply outputs a voltage corresponding to the voltage command value input from the determination unit, and the determination unit outputs the voltage command value to the power supply as the standby voltage value. The input voltage value of the leak detection unit is varied before and after the standby voltage value, and calculated from the voltage command value or the input voltage value and the input current value detected by the current detection unit. By comparing the conducted conduction or resistance value with a predetermined threshold value, it may be determined that a leak has occurred in at least one of the leak detection units.

In this way, the conductance or resistance value is calculated by fluctuating the input voltage value of the leak detection unit before and after the standby voltage value, and the leakage is determined by this. Therefore, the leak is determined by a physical quantity different from the input current value. Can be determined.

In the liquid leakage detection device of the present invention, the power supply outputs a voltage corresponding to the voltage command value input from the determination unit, and the determination unit sweeps the voltage command value output to the power supply. The input voltage value of the leak detection unit is swept, and each of the leak detection units is made conductive in the order in which they are connected to the start end, and the voltage command value or the input voltage value and the input detected by the current detection unit are performed. By comparing the conductance or resistance value calculated from the current value with a predetermined threshold value, it is determined that a leak has occurred in at least one of the leak detecting units in a conducting state. You may.

In this way, the conductance or resistance value is calculated by sweeping the input voltage value of the liquid leakage detection unit, and the leakage is determined by this. Therefore, the leakage can be determined by a physical quantity different from the input current value. can.

In the liquid leakage detection device of the present invention, the power supply outputs a voltage corresponding to the voltage command value input from the determination unit, and the determination unit sweeps the voltage command value output to the power supply. The input voltage value of the leak detection unit is swept, and each of the leak detection units is made conductive in the order in which they are connected to the start end, and the range from the start end of the leak detection unit to one of the leak detection units. The input current value detected by the current detection unit when the current detection unit is set to the conduction state, and the current value detected by the current detection unit when the range other than one of the leak detection units is set to the continuity state. The conductance of one of the leak detection units is calculated using the input current value, and the calculated conductance is compared with a predetermined threshold to identify the leak detection unit in which the leak has occurred. May be good.

In this way, the input voltage value of the leak detection unit is swept, the leak detection units are conducted in the order in which they are connected to the starting end, the conductance of each leak detection unit is calculated, and the calculated conductance is set as a predetermined threshold value. By comparing, it is possible to identify the leak detection unit in which the leak has occurred. This makes it possible to improve the detection reliability of the leaked portion with a simple configuration.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to monitor the leakage of an object having a complicated shape with a simple configuration.

It is a system diagram which shows the structure of the leakage detection apparatus of 1st Embodiment. It is a system diagram which shows the structure of the liquid leakage detection unit of the liquid leakage detection apparatus shown in FIG. It is a graph which shows the characteristic of the current with respect to the voltage of the constant voltage element which connected the ideal Zener diode in anti-series. It is a system diagram showing the flow of current when the branch leak leak detection unit leakage in U _n of the detection portion of the leakage detecting device shown in FIG. 1 has occurred. It is a graph which shows the voltage value applied to each liquid leakage detection unit when the input voltage value is raised in the liquid leakage detection apparatus shown in FIG. 1. It is a graph which shows the voltage value applied to each liquid leakage detection unit when the input voltage value is a standby voltage value in the liquid leakage detection apparatus shown in FIG. 1. It is a graph which shows the time change of three kinds of input voltage values input to the leakage detection apparatus shown in FIG. The change characteristic (VI characteristic) of the input current value with respect to the change of the input voltage value when the leak occurs and when the leak does not occur in the leak detection device shown in FIG. 1, and the input current value due to the occurrence of the leak. It is a graph which shows the change of. Input current value change characteristics (VI characteristics) with respect to changes in the input voltage value when liquid leakage occurs and when liquid leakage does not occur in the liquid leakage detection device shown in FIG. 1 and input when liquid leakage occurs. It is a graph which shows the change of the input current value when the voltage is changed before and after the standby voltage value. The change characteristic (VG characteristic) of the conductance with respect to the change of the input voltage value when the leak occurs and the case where the leak does not occur in the leak detection device shown in FIG. 1 and the change of the conductance due to the occurrence of the leak are shown. It is a graph which shows. It is a system diagram showing the flow of current when the branch leak leak detection unit leakage in U _n of the detection portion of the leakage detecting device shown in FIG. 1 has occurred. Change characteristics of the input current value with respect to the change of the input voltage value when the branch leak leak detection unit leakage in U _n of the detection portion of the leakage detecting device shown in FIG. 1 does not occur if the leakage occurred ( It is a graph which shows the VI characteristic), the change of the input current value with respect to the change of the input voltage value in each leakage detection unit when the input voltage value is swept, and the change of the conduction range. It is a graph which shows the change (VG characteristic) of conductance with respect to the input voltage value calculated based on the VI characteristic shown in FIG. It is a graph which shows the conductance of each leakage detection unit obtained from the characteristic shown in FIG. System diagram illustrating a leak detection unit U ₂ stem leakage detecting portion of the leakage detecting device shown in FIG. 1, the flow of current when the liquid leakage in leakage detection unit U _n branches leak detection unit has occurred Is. Two leak detection unit U _2, the change characteristics of the input current value and liquid leakage in U _n is to changes in the input voltage value in the case of no occurrence of the case and leakage occurred in leakage detecting device shown in FIG. 1 (VI It is a graph which shows the characteristic), the change of the input current value with respect to the change of the input voltage value in each leakage detection unit when the input voltage value is swept, and the change of the conduction range. It is a graph which shows the change (VG characteristic) of conductance with respect to the input voltage value calculated based on the VI characteristic shown in FIG. It is a graph which shows the conductance of each leak detection unit obtained from the characteristic shown in FIG. It is a system diagram which shows the structure of the leakage detection apparatus of 2nd Embodiment. It is a system diagram showing the flow of current when the branch leak leak detection unit leakage in U _m of the detection portion of the leakage detecting device shown in FIG. 19 is generated. FIG. 19 is a system diagram showing a current flow when a leak occurs in _{the leak detection unit U 2} of the trunk leak detection unit of the leak detection device and the leak detection unit U _{m of the branch leak detection unit.} Is. It is a system diagram which shows the structure of the leakage detection apparatus of 3rd Embodiment. It is a system diagram which shows the structure of the leakage detection apparatus of 4th Embodiment. It is a system diagram which shows the structure of the liquid leakage detection apparatus of 5th Embodiment. It is a system diagram which shows the structure of the leakage detection apparatus of 6th Embodiment. It is a system diagram which shows the structure of the liquid leakage detection apparatus of 7th Embodiment. It is a system diagram which shows the structure of a repeater. It is a wiring diagram which shows the structure of the repeater shown in FIG. 27. The change characteristic (VI characteristic) of the input current value with respect to the change of the input voltage value when the leak occurs and when the leak does not occur in the leak detection device shown in FIG. 26, and the input current value due to the occurrence of the leak. It is a graph which shows the change of. It is a system diagram which shows the structure of the liquid leakage detection apparatus of 8th Embodiment. It is a system diagram which shows the state which attached the leakage detection apparatus of 9th Embodiment to the pipe with a branch. It is explanatory drawing which shows the other example of the node applied to the leakage detection apparatus shown in FIGS. 1, 19, 22-26, 30, 31.

<Structure of the leak detection device 100 of the first embodiment>
Hereinafter, the leak detection device 100 of the embodiment will be described with reference to the drawings. As shown in FIG. 1, the leak detection device 100 includes a trunk leak detection unit 40, a branch leak detection unit 50, a power supply 81 connected to a start end 41 of the trunk leak detection unit 40, and a trunk leak. It is composed of a current sensor 82, which is a current detection unit that detects the input current value of the detection unit 40, and a determination unit 90 that determines liquid leakage based on the input current value detected by the current sensor 82.

As shown in FIG. 1, the trunk leak detection unit 40 is formed by connecting a plurality of leak detection units U _{1 to} U ₅ in series. Further, the branch leak detection unit 50 is formed by connecting a plurality of leak detection units U _{6 to} U ₈ in series, and the branch start end 51 of the branch leak detection unit 50 is the leak of the trunk liquid detection unit 40. It is connected to the detection unit U _2. The number of leak detection units U constituting the trunk leak detection unit 40 and the branch leak detection unit 50 is not limited to five or three, respectively, and may be any number, one, or six or more. It may be composed of.

With reference to FIG. 2, the configuration of one leak detection unit U _n. As shown in FIG. 2, leak detection unit _{U n} has a node ND _n that includes a constant voltage element _{D n,} and a leak detection zone 30 consists of a pair of conductive lines 31, 32. The node ND _n has a pair of connection lines 12 connecting the pair of start end side terminals 13, 15 and the pair of end side terminals 14, 16 and the start end side terminals 13, 15 and the end side terminals 14, 16 in parallel. Includes. As shown in FIG. 2, the intermediate of the connection line 12 which connects the one start terminal 13 and end terminal 14, constant voltage element D _n it is connected so as to be disposed interposed. Also, the other starting end side terminal 15 and the terminal-side terminals 16 are connected by a connecting line 12, constant voltage element D _n is not connected. A pair of conductive wires 31 and 32 of the liquid leakage detection band 30 are connected to the pair of terminal terminals 14 and 16, respectively, and the end portions 31e and 32e of the pair of conductive wires 31 and 32 on the terminal side are leaking liquid. the distal end of the sensing unit U _n. Further, the pair of the starting side terminals 13 and 15, the starting end of the leak detection unit U _n.

As shown in FIG. 1, leak detection unit U ₂ from the beginning 41 of the second stem leakage detecting unit 40 has a pair of conductive lines 31 of the leak detection zone 30 of the leak detection unit U _n previously described , 32 is a leakage detection unit with a branch line in which a branch line 60 composed of a pair of conductive lines 61 and 62 is connected to the connection points 63 and 64. The pair of connection points 63 and 64 constitutes a connection point 65 to the liquid leakage detection zone 30 of the branch line 60. Incidentally, the branch line 60, rather than being connected to a pair of conductive lines 31 and 32 may be directly connected to the end terminal 14, 16 of the leak detection unit U _n. Further, a plurality of branch lines 60 may be configured to be connected to the liquid leakage detection band 30 or the terminal terminals 14 and 16.

Constant voltage element D _n, as shown in FIG. 3, when the absolute value of the applied voltage is conducted to reach a predetermined rising voltage value Vf, the absolute value of the applied voltage does not reach the rising voltage value Vf is not It is an element that becomes conductive. In leakage detection device 100 of the present embodiment, the constant voltage element D _n, the configuration of the constant voltage element D _n of characteristic as shown in FIG. 3 by connecting the Zener diode 11a rising voltage value Vf, and 11b to the anti-series doing. Further, in the liquid leakage detection device 100 of the present embodiment, it will be described that the rising voltage values of the _{constant voltage elements D 1 to} D _{8 are all the same in Vf.} However, the configuration of the constant voltage element D _n is not limited thereto. This point will be described later.

The conductive wires 31 and 32 are non-conducting when there is no leakage, and are mutually conductive due to the leakage when the leakage occurs. The conductive wires 31 and 32 may be made of, for example, twisted copper wires covered with a hygroscopic insulating film or the like.

As shown in FIGS. 1 and 2, stem leakage detecting unit 40, leak detection distal end 31e of the conductive wire 31, 32 is an end of the terminal side of leak detection units U _n, the 32e It is configured by sequentially connecting to the start end side terminals 13 and 15 which are the end ends of the unit Un _{+ 1 on the start end side.} Then, the starting side terminals 13, 15 of the leak detection unit U ₁ from the starting end 41 first stem leakage detection unit 40 constitutes a leading end 41 of the stem leakage detecting portion 40, stem leakage detector 40 distal end 31e of the starting end 41 the fifth leak detection unit _{U 5} conductive lines 31 and 32, 32e constitute the end 42 of Mikimo liquid detecting unit 40. Further, the terminal 42 of the stem leak detection unit 40 is open. Thus, stem leakage detecting unit 40, the terminal a leakage detection unit U _n including node ND _n disposing the constant voltage element D _n between the starting end side of the connecting line 12 of the conductive wire 31 from the beginning 41 42 It is connected in series toward.

Branch leakage detecting unit 50, like the stem leakage detecting unit 40, which are connected in series towards the branch terminal 52 a leak detection unit U _n from the branch starting end 51. Branch branch leak detection unit 50 start 51 is connected to the end of the branch line 60 connected to the leak detection unit U ₂ of Mikimo liquid detecting unit 40. Further, the branch end 52 of the branch leak detecting unit 50 is open.

As shown in FIG. 1, each of the leak detection units U _{1 to} U ₈ is assigned a unit number N. Unit number N is the current voltage value of the constant-voltage element D _n included in each leak detection unit U _n connected in series from the starting 41 of stem leakage detecting portion 40 to the leak detection unit U _n The integrated voltage value (= ΣVf) of the rising voltage value Vf is attached in ascending order.

Since the liquid leakage detection unit U ₁ is directly connected to the start end 41, the integrated voltage value from the start end 41 to the liquid leakage detection unit U _{1 is Vf.} From start 41 to leak detection unit U _2, since the leak detection unit U ₁ and leak detection unit U ₂ are connected in series, the integrated voltage value from the beginning 41 to leak detection unit U ₂ is , Vf + Vf = 2Vf. Moreover, from the beginning 41 to leak detection unit _{U 3,} since leak detection unit _U 1 ~U ₃ are connected in series, the integrated voltage value from the beginning 41 to leak detection unit _{U 3} is, Vf + Vf + Vf = It becomes 3Vf. Hereinafter, similarly, the integrated voltage value from the start end 41 to the leak detection unit U _{4 is 4} Vf, and the integrated voltage value from the leak detection unit U _{5 is 5} Vf.

Further, from the start end 41 of the trunk liquid leakage detection unit 40 to the liquid leakage detection unit U ₆ of the branch liquid leakage detection unit 50, three liquid leakage detection units U of the liquid leakage detection units U ₁ , U ₂ , and U ₆ are connected in series. The integrated voltage value from the start end 41 to the leak detection unit U ₆ is Vf + Vf + Vf = 3Vf. Similarly, the integrated voltage value from the start end 41 to the leak detection unit U ₇ is 4 Vf, and the integrated voltage value from the leak detection unit U ₈ is 5 Vf.

Unit number N, since the integrated voltage value from the start 41 (= ΣVf) are assigned in the ascending order, the unit number N of leak detection unit U ₁ of the integrated voltage value is smallest Vf is 1, the accumulated voltage leakage unit number of the sensing unit _{U 2} is 2 2Vf, integrated voltage value is 3Vf leak detection unit _U 3, unit number _{U 6} is 3, the integrated voltage value is 4Vf leak detection unit _U 4, _{U 7} the unit number N 4, unit number N of leakage accumulated voltage is 5Vf sensing unit _U 5, _{U 8} is 5. As described above, in the liquid leakage detection device 100 of the present embodiment, one unit number N is attached to the plurality of liquid leakage detection units U.

Starting side terminals 13, 15 of the leak detection unit U ₁ constituting the starting end 41 of the stem leakage detection unit 40 is connected to the power source 81 through the covering wire 33. A current sensor 82 is connected between the power supply 81 and _one of the start end side terminals 13 of the liquid leakage detection unit U1. Here, the coated electric wire 33 is an electric wire coated with an insulating film and does not conduct with each other even if a leak comes into contact between the pair of coated electric wires 33.

The power supply 81 is an AC power supply. The power supply 81 may be, for example, an AC 100 Hz and an output voltage of about 10 V. The current sensor 82 is an alternating current detector that detects an alternating current value. The determination unit 90 is a computer including a CPU 91, a memory 92, an input interface 93 to which the power supply 81 and the current sensor 82 are connected, and an output interface 94 for outputting the calculation result of the CPU 91. The CPU 91, the memory 92, the input interface 93, and the output interface 94 are connected by a data bus 95. The power supply 81 outputs a voltage corresponding to the voltage command value input from the determination unit 90 of the determination unit 90. The configuration of the determination unit 90 is not limited to this, and may be configured by, for example, an analog circuit.

<Leakage determination operation of the leak detection device 100>
Hereinafter, the liquid leakage determination operation of the liquid leakage detection device 100 will be described with reference to FIGS. 4 to 10. FIG. 4 is a generalization of the reference numerals of the system diagram shown in FIG. 1 for the purpose of explaining the liquid leakage determination operation of the liquid leakage detection device 100. In FIG. 4, the description of the determination unit 90 is omitted. 4, stem leakage detection unit 40 is obtained by connecting the leak detection unit _{U 1 ~U k +} 1 in series. Further, the branch leak detection unit 50 is connected in series with the leak detection units UK _{+ 2 to Un + 1.} Branch branch leak detection unit 50 start 51 is connected to the leak detection zone 30 of the leak detection unit U ₂ via the branch line 60. The number of liquid leakage detection units U [(k + 1) -2] connected to the terminal side of the _{liquid leakage detection unit U 2} of the trunk liquid leakage detection unit 40, and the liquid leakage detection unit constituting the branch liquid leakage detection unit 50. It is the same as the number of U [(m + 1)-(k + 2) + 1]. Each leak detection unit U is assigned a unit number N in the same order as described above. Leakage unit number N is 1 the sensing unit _{U 1,} unit number N is a leak detection unit _{U 2,} leak detection unit _{U 3, U k + 2} of the unit number N is 3, leak detection unit _U k, U _{The unit number N of n} is m, and the unit number N of the leak detection unit U _{k + 1 and Un + 1} is m + 1. Here, k, n, and m are natural numbers, and k <k + 1 <k + 2 <n-1 <n <n + 1. Hereinafter, the input voltage value, the applied voltage of each leak detection unit U, and the conduction range A will be described with reference to FIGS. 5 and 6.

<Input voltage value and continuity range>
When the input voltage value is zero, all the constant voltage elements D are off and non-conducting. As shown in FIG. 5, when the input voltage value of the starting end 41 is increased from zero to the rising voltage value Vf, the voltage of Vf is applied to the constant voltage element D _{1 of the liquid leakage detection unit U 1 having the unit number N 1.} .. Then, the constant voltage element D ₁ is turned on. Since the voltage drop of the constant voltage element D ₁ is Vf, when the starting voltage exceeds Vf, a voltage starts to be applied between the conductive wires 31 and 32 of the _{liquid leakage detection unit U 1.} As a result, the leak detection unit U ₁ can detect the leak. After that, as the input voltage is increased, the voltage between the conductive wires 31 and 32 gradually increases from zero. At this time, the conduction range A ₁ is only the liquid leakage detection unit U _{1 having the unit number N 1.}

As shown in FIG. 5, increasing the input voltage value to twice = 2 × Vf rising voltage value Vf, unit number N is the voltage between the first leak detection unit U ₁ of the conductive lines 31 and 32 Vf reached, the unit number N 2 of leak detection units U ₂ of the constant voltage element D ₂ to the rising voltage value Vf is applied. Thus, the constant voltage element D ₂ is turned on, it takes a voltage began between conductive lines 31 and 32 of the leak detection units U _2, it is possible to leak detection of leak detection unit U _2. The continuity range A _{2 at} this time is the liquid leakage detection units U ₁ and U ₂ having unit numbers N 1 and 2. Further, when the input voltage value is raised to 3 times the rising voltage value Vf = 3 × Vf, the rising voltage value rises to the constant voltage elements D ₂ and D _{k + 2} of _{the liquid leakage detection units U 3} and _{UK + 2 having the unit number N 3.} Vf is applied. Thus, the constant voltage element _{D 2, D k +} 2 is turned on, it takes a voltage began between leak detection unit _{U 3, U k + 2} of the conductive wire 31, 32, leak detection unit _{U 3, U k + 2} of the leak Detection is possible. Conducting range _{A 3} when this is the unit number leak detection unit N from the _{1 3 U 1 ~U 3, U} k + 2

Similarly, when the input voltage value is _{increased to V m} = m × Vf, the constant voltage element D of the leak detection unit U having the unit number N is turned on, and the leak detection unit U having the unit number N is 1. each leak detection unit _U 1 _~U k from ₁ to leak detection unit U of the unit number n _m, which conducts _{U k} + 2 ~U _n. Conduction range when this is A _m. As described above, when the input voltage value is increased, one or a plurality of liquid leakage detection units U are sequentially conducted in the order of the unit number N each time the input voltage value is increased by Vf.

Then, as shown in FIG. 6, when the input voltage value is _raised to V Nend = Nend × Vf (where Nend is the maximum unit number N), the leak detection unit U having the unit number N is 1. _{All the leak detection units U from 1} to the leak detection unit U whose unit number N is Nend are electrically connected, and all the leak detection units U can detect the leak. _{Therefore, by setting the} input voltage value to a standby voltage value V ₀ higher than that of V Nend, all the leak detection units U can detect the leak.

Hereinafter, the operation when the leakage is detected by _{setting the} input voltage value to the standby voltage value V _{0 higher than that of V Nend will be described.} In this case, as shown by line a in FIG. 7, the input voltage value is _{set to a constant standby voltage value V 0} (first determination operation), and as shown in line b in FIG. 7, the input voltage value is set to standby voltage. A method of varying before and after the value V ₀ (second judgment operation) and a method of sweeping the input voltage value between zero and the standby voltage value V ₀ as shown by line c in FIG. 7 (third judgment operation). There is. Hereinafter, the first determination operation will be described first, and then the second and third determination operations will be described. In the following description, as shown in FIG. 4, the unit number N is fluid leakage in leak detection unit U _n branches leak detection unit 50 of the m will be described as having been generated.

<First judgment operation>
The determination unit 90 outputs a voltage command value that keeps the output voltage constant at the standby voltage value V _{0 to the power supply 81.} Accordingly, the power source 81 applies a standby voltage value V ₀ constant voltage start 41 of stem leakage detection unit 40.

As shown in FIG. 8, when no liquid leakage has occurred, no current flows between the conductive wires 31 and 32 of each liquid leakage detection unit U, so that the input current value detected by the current sensor 82 is zero. It has become.

On the other hand, as shown in FIG. 4, when the unit number N is leakage occurs in leak detection unit _{U n} of m, between the leak detection unit _{U n} of conductive lines _31,32, I _n = _G n A current of (V ₀ −V _{m) flows.} Here, _{G n} is the conductance between the leak detection unit _{U n} of the conductive lines 31 and 32. At this time, since no liquid leakage has occurred from the _{liquid leakage detection unit U 3 of the trunk liquid detection unit 40 to UK + 1} , the liquid leakage detection unit U on the trunk liquid detection unit 40 side having the unit number N of m. _No current flows between the conductive wires 31 and 32 of k. Thus, leak detection unit _U k of the unit number N m, the total conductance _{G m} of _{U n} is equal to _{G n.}

Therefore, the determination unit 90 compares the input current value detected by the current sensor 82 with the predetermined threshold value, and determines that the liquid leakage has occurred when the input current value becomes larger than the predetermined threshold value. .. When the determination unit 90 determines that a leak has occurred, the determination unit 90 issues an alarm for the occurrence of the leak to the external device via the output interface 94.

Here, the predetermined threshold value can be freely set, but it may be determined by a test or the like according to the type of the liquid or the like.

<Second judgment operation>
As explained above, when increasing the input voltage value to _V m = m × Vf, leak detection unit _U k of the unit number N m, the constant voltage element _D k of _{U n, D n} are turned on , the unit number n is leak detection unit _U 1 _~U k from 1 to _m, is _{U k} + 2 ~U _n conductive. In this case, when the liquid leakage unit number N is leak detection unit U _n of m occurs, current starts flowing between the leak detection unit U _n of the conductive lines 31 and 32. At this time, the conductance of the leaked portion 35 is _Gn . Thereafter, increasing the input voltage value, the voltage between the leak detection unit U _n of the conductive wire 31, 32 is increased, the input current value gradually increases. Therefore, when the leakage occurs at the leak detection unit U _n, the change characteristics of the input current value with respect to the change of the input voltage values (hereinafter, referred to as VI characteristics), as indicated by the broken line in FIG. 9, the input voltage value V _The input current value is zero up to _{m, and when the input voltage value exceeds V m} , the input current value increases with a certain inclination. Further, the conductance of the variation characteristics to changes in the input voltage values (hereinafter, referred VG characteristics), as indicated by the broken line in FIG. 10, the conductance G is the input voltage value to V _m is zero, the input voltage value V _m When it exceeds, the conductance G becomes _{the conductance Gn of the leaked portion 35.}

Therefore, in the second determination operation, as shown in FIG. 9, the input voltage value is _{fluctuated by ΔV before and after the standby voltage value V 0} , and the change amount ΔI of the input current value from the change of the input current value detected by the current sensor 82. , The conductance G = ΔI / ΔV is calculated, and the calculated conductance G is compared with a predetermined threshold value to determine the leakage.

The determination unit 90 fluctuates the voltage command value output to the power supply 81 by ΔV before and after the _{standby voltage value V 0.} Power source 81 is varied by ΔV the input voltage applied to the starting end 41 of the stem leakage detection unit 40 according to the voltage command value before and after the standby voltage value V _0. The determination unit 90 detects the input current value by the current sensor 82. The determination unit 90 calculates the amount of change ΔI of the input current value from the two input current values corresponding to the two different voltage command values. Then, the determination unit 90 calculates conductance G = ΔI / ΔV and compares it with a predetermined threshold value. Then, as shown in FIG. 10, when the calculated conductance G is larger than a predetermined threshold value, it is determined that the liquid leakage has occurred.

The calculation of the change amount ΔI of the input current value is not limited to using two input current values corresponding to two different voltage command values, and the input current corresponding to three or more voltage command values. It may be calculated using a value. Further, in the second determination operation, the resistance value R = ΔV / ΔI may be calculated instead of the conductance G, and it may be determined that leakage occurs when the resistance value is smaller than a predetermined threshold value.

Further, in the above description, the change amount ΔI of the input current value is calculated from the two input current values corresponding to the two different voltage command values. However, the voltage sensor that detects the input voltage value of the start end 41 is used. It may be provided to detect the input voltage value, and the input voltage value detected by the voltage sensor may be used instead of the voltage command value. In this case, the amount of change ΔI of the input current value is calculated from the two input current values corresponding to the two different input voltage values.

<Third judgment operation>
In the third determination operation, the determination unit 90 _{sweeps the voltage command value between zero and the standby voltage value V 0} as shown by line c in FIG. 7, and corresponds to the two voltage command values changed by the sweep. The amount of change ΔI of the input current value is calculated from the two input current values. Then, as in the second determination operation, conductance G = ΔI / ΔV is calculated, and when the calculated conductance G is larger than a predetermined threshold value, it is determined that liquid leakage has occurred. In this case, the conductance G may be calculated using the input current value at the minimum voltage value and the input current value at the maximum voltage value.

Further, as in the second determination operation, the calculation of the change amount ΔI of the input current value is not limited to using the two input current values corresponding to the two voltage command values, and the voltage command is three or more. It may be calculated using the input current value corresponding to the value. Further, the resistance value R = ΔV / ΔI may be calculated instead of the conductance G, and it may be determined that leakage occurs when the resistance value is smaller than a predetermined threshold value. Further, as in the second determination operation described above, the change amount ΔI of the input current value may be calculated using the input voltage value detected by the voltage sensor instead of the voltage command value.

Further, in the explanation of this operation, the voltage command value is _{swept between zero and the standby voltage value V 0} , but if the maximum value of the voltage command value is _{larger than V Nend} = Nend × Vf, the standby voltage. may be smaller than the value V _0, it may be larger than the standby voltage value V _0.

As described above, in the liquid leakage detection device 100 of the present embodiment, it can be seen that liquid leakage has occurred in the trunk liquid leakage detection unit 40 or the branch liquid leakage detection unit 50 by one power supply 81 and one determination unit 90. Since it can be determined, it is possible to monitor the leakage of an object having a complicated shape including branching with a simple configuration. Further, in the first determination operation, it is possible to determine the occurrence of liquid leakage in a short time with a simple configuration in which the _{standby voltage value V 0 is constant at a predetermined voltage value.} Further, in the second and third determination operations, the conductance or resistance value is calculated by fluctuating the input voltage value before and after the _{standby voltage value V 0 or sweeping the input voltage value, whereby the leakage of liquid is calculated.} Since the determination is made, the leakage can be determined by the physical quantity different from the input current value.

In the above description, the liquid leakage in leak detection unit U _n branches leak detection unit 50 of the unit number N m are described as occurring, the unit number of stem leakage detecting portion 40 of the m leakage If a leak occurs in the detection unit U _k , or if a leak occurs in the leak detection units U ₁ and U ₂ of the trunk leak detection unit 40 with unit numbers N 1 and 2, the same operation is performed. Leakage can be determined.

<Specific operation of unit number N where liquid leakage occurred>
Hereinafter, the operation of specifying the unit number N in which the leak has occurred will be described with reference to FIGS. 11 to 14. FIG. 11 is a generalization of the reference numerals of the system diagram shown in FIG. 1 for the purpose of explaining the specific operation of the unit number in which the leak has occurred in the leak detection device 100. Unit numbers are assigned as in FIG.

Specific operation of the generated unit number N of leakage sweeps between zero and the standby voltage V ₀ of the voltage command value as the line c in FIG. 7, the order of the leak detection unit U the unit number N conduction is, leak detection unit _U 1 m-1 of the unit numbered from _{1 ~U k-1, U k} + 2 total conductance in _~U state where _n-1 and the conductive state _[G 1 + · · + and _{G k-1 + G k +} 2 + ·· + G n-1], a total of at state 1 leak detection unit _U 1 _~U k the unit numbered as _m, the conductive state of _{U k} + 2 ~U _n conductance _{[G 1 + ·· + G k} + G k + 2 + ·· + G n] leak detection unit from the difference unit number n is m and _U k, each conductance _G k of _{U n,} the total conductance _{G m} of _{G n} calculated is the calculated conductance G _m intended to identify the generated unit number N of comparison to leakage with a predetermined threshold value. Hereinafter, leak detection unit _U k of the unit number N m, the conductance _G k of _{U n,} the total conductance _{G m} a leak detection unit _{G n [U k, U n} ] that conductance _{G m} of.

<Input voltage value, conductance and conduction range>
_{When the input voltage value is increased from zero to the standby voltage value V 0 as} shown by the line c in FIG. 7, each leak detection unit U has a unit number N as described above with reference to FIG. Conducts in order of. FIG. 12 is a graph in which the change in the input current value with respect to the change in the input voltage value at each unit number N when the input voltage value is swept to the VI characteristic and the change in the conduction range are superimposed. The solid line in FIG. 12 shows the VI characteristics when no liquid leakage occurs, and the broken line shows the VI characteristics when liquid leakage occurs in any of the leak detection units U having the unit number N of m.

As shown in FIG. 12, leak detection unit _U 1 _~U k of Increasing the input voltage value to between _{V m} and _{V m + 1} from unit number 1 _m, the _{U k} + 2 ~U _n becomes conductive. When the input voltage value is fluctuated by ΔV in this state and the change amount ΔI of the input current value is calculated from the input current value detected by the current sensor 82, as shown in FIG. 13, the conductance G calculated by ΔI / ΔV , as shown in the following equation (1), the conductance _G 1, _{G 2} may leak from the unit number 1 that the conductive state of the m detection unit _U 1, _{U 2} and, leak detection unit [U _{3, U k + 2] ~} [U k, the total conductance of each conductance _G 3 ~G _m of _{U n].}

Similarly, when the input voltage value is _{raised to between V m-1} and V _{m , the leak detection units U 1 to} U _k-1 and U _{k + 2 to} Un-1 of unit numbers 1 to m _-1 are in a conductive state. _{Therefore, the conductance G calculated by ΔI / ΔV is the conductance of the liquid leakage detection units U 1} and U ₂ of the unit numbers 1 to m-1 in the conducting state, as shown in the following equation (2). It is the total conductance of each conductance G _{3 to} G _{m-1 of G 1} , G ₂ and the leak detection unit [U ₃ , U _{k + 2} ] to [U _k-1 , _Un-1].

Therefore, it is possible to calculate the conductance _{G m} of formula (1) from as shown in Figure 14 by subtracting Equation (2), leak detection unit with a unit number _{N = m [U k, U} n]. Then, the conductance G _m and the unit number by comparing a predetermined threshold value N = leak detection unit m is attached U _k, it is possible to determine the occurrence of leakage in the U _n. In this case, although it is possible to identify the generated unit number N of leakage, it can not be specified whether leak detection unit U _k that unit number N is _attached, and liquid leakage in either U _n occurs .. In this case, the maintenance staff inspects the site and identifies which leak detection unit U the leak occurred in.

<Details of specific operation of the unit number where the leak occurred>
Hereinafter, the details of the specific operation of the unit number N in which the leak has occurred will be described with reference to FIGS. 12 to 14. In the following description, as shown in FIG. 11, the unit number N is fluid leakage in leak detection unit U _n branches leak detection unit 50 of the m will be described as having been generated.

The determination unit 90 sweeps the voltage value command value from zero to the standby voltage value V _{0 along the line c in FIG. 7.} Thus, the power supply 81 sweeps the input voltage applied to the starting end 41 of the stem leakage detection unit 40 according to the voltage command value from zero to a quiescent voltage value V _0. As described above, the input voltage value is the unit number N reaches the Vf becomes possible leakage detected by leak detection unit U ₁ of 1.

The determination unit 90 sweeps the voltage command value from Vf to a value slightly smaller than 2 × Vf, and sweeps the input voltage value from Vf to a value slightly smaller than 2 × Vf. During this time, the unit number N is in the only leak detection unit U ₁ of 1 conduction range (conduction range A _1). During this period, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the change amount ΔI of the input current value is calculated from the detected input current value, and the conductance G ₁ = ΔI / ΔV is calculated. No leak has occurred in the leak detection unit U1 with unit number N ₁ , and as shown in FIG. 12, the input current value remains zero while the input voltage value is between Vf and 2 × Vf. Therefore, conductance G ₁ = ΔI / ΔV = 0.

Next, the determination unit 90 sweeps the voltage command value from 2 × Vf to a value slightly smaller than 3 × Vf, and sweeps the input voltage value from 2 × Vf to a value slightly smaller than 3 × Vf. During this period, the liquid leakage detection units U ₁ and U ₂ having unit numbers N 1 and 2 are in the conduction range (conduction range A ₂ ). During this time, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the amount of change ΔI of the input current value is calculated from the detected input current value, and the total value of the conductances of _{the leak detection units U 1} and U _{2 having the unit number N in the conduction range 1 and 2 [G 1} + G ₂ ]. = ΔI / ΔV is calculated.

Leak in leak detection unit U _1, U ₂ unit number N is 1, 2 is not generated, as shown in FIG. 12, the input voltage value is input current value between 3 × Vf from 2 × Vf Since is still zero, ΔI = 0, and the total conductance value [G ₁ + G ₂ ] = ΔI / ΔV = 0. The determination unit 90 subtracts the previously calculated G _{1 from [G 1} + G ₂ ] to obtain the result of _{G 2 = 0.}

Similarly, the determination unit 90 sweeps the voltage command value, calculates the total conductance ΣG of the leak detection unit U in the conduction range every time the conduction range expands in the order of the unit number N, and calculates the previous conductance. Each conductance G of the leak detection unit U of each unit number is calculated from the difference from the total value of conductance calculated in the range. Since the unit number 1 m-1 of the leak detection unit _{U 1 ~U k-1, U} k + 2 ~U n-1 in the leakage has not occurred, as shown in FIG. 12, the input voltage value _{V m} Until, the input current value is zero, and the conductance G of each unit number N calculated as shown in FIG. 13 is all zero.

The determination unit 90 sweeps the voltage command value from m × Vf to a value slightly smaller than (m + 1) × Vf, and sweeps the input voltage value from m × Vf to a value slightly smaller than (m + 1) × Vf. During this time, the consist unit number N is 1 leak detection unit _U 1 _~U k of _m, and _{U k} + 2 ~U _n conduction range (conduction range _{A m).} During this time, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the amount of change ΔI of the input current value is calculated from the detected input current value, and the leak detection units U ₁ , U ₂ and the leak detection unit [U ₃ , calculating a _{U k + 2] ~ [U} k, the sum of the conductance of _{U n] [G 1 + ···} + G m] = ΔI / ΔV.

Since the unit number N is fluid leakage in leak detection unit U _n of m occurs, as shown in FIG. 12, the input voltage value is a change in the input current value during changes by ΔV is not zero, [G ₁ + ... + G _m ] = ΔI / ΔV is a non-zero value. Determination unit 90 _obtains the values of _{G m} by subtracting the previously calculated from _{[G 1 + ··· + G m} ] [G 1 + ··· + G m-1].

The determination unit 90 sweeps the voltage command value from (m + 1) × Vf to a value slightly smaller than (m + 2) × Vf, and sweeps the input voltage value from (m + 1) × Vf to a value slightly smaller than (m + 2) × Vf. do. During this period, the leak detection units U _{1 to} U _{k + 1} and U _{k + 2 to} Un _{+ 1} having unit numbers N from 1 to m + 1 are in the conduction range (conduction range _{Am + 1} ). During this time, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the amount of change ΔI of the input current value is calculated from the detected input current value, and the leak detection units U ₁ , U ₂ and the leak detection unit [U ₃ , calculating a _{U k + 2] ~ [U} k + 1, the total value of the conductance of _{U n + 1] [G 1} + ··· + G m + 1] = ΔI / ΔV.

Since the unit number N is not m + 1 of the leak detection units _{U k + 1, U n +} 1 in leakage occurs, as shown in FIG. 12, the change in the input current value between the input voltage value is ΔV changes, unit number n is the same as if the leak detection unit _U 1 _~U k from 1 to _m, is _{U k} + 2 ~U _n has a conductive range (conduction range _{a m),} the slope of the VI characteristics are also the same. Therefore, [G ₁ + ... + G _{m + 1} ] = ΔI / ΔV has the same value as _{G m.} The determination unit 90 subtracts _{[G 1} + ... + G _m ] = G _m calculated earlier from _{[G 1} + ... + G _{m + 1} ] = G _m to obtain a value of _{G m + 1 = 0.}

Each conductance G ₁ ~G m + ₁ from the unit number N is 1 calculated in the above manner to m + 1, as shown in FIG. 14, leak detection unit of the generated unit number N of leakage is m [U _k , _Un ] only the conductance is a non-zero value G _m , and each conductance G of the other unit number N leak detection unit U is zero.

The determination unit 90 compares each conductance G _{1 to} G _{m + 1} of each calculated unit number with a predetermined threshold value, and identifies m having a conductance G larger than the predetermined threshold value as the unit number N in which the leak has occurred.

In the operation for specifying the unit number N in which the leak has occurred described above, the unit number N in which the leak has occurred can be specified, but the two leak detection units with the same unit number N = m are assigned. U _k, liquid leakage in either of U _n it is not possible to identify whether it has occurred. In this case, the maintenance staff inspects the site and identifies which leak detection unit U the leak occurred in.

Next, with reference to FIGS. 15 18, the leak detection unit U ₂ unit number 2 stem leakage detecting unit 40, the leakage in leak detection unit U _n of the unit number m of branches leak detection unit 50 The operation of specifying the unit number in which the leak occurred when the liquid is generated will be described. The specific operation similar to the operation of the unit number N when liquid leakage in leak detection unit U _n of the unit number m described earlier occurs briefly described. FIG. 15 is a generalization of the reference numerals of the system diagram shown in FIG. 1 for the purpose of explaining the specific operation of the unit number in which the leak has occurred in the leak detection device 100. A unit number similar to that in FIG. 11 is assigned.

Similar to previously as described with reference to FIG. 11 to 14, since the leak detection unit U ₁ of the unit number N is 1 leakage has not occurred, a G 1 _{= 0.}

Since a leak has occurred in _{the leak detection unit U 2} having the unit number N 2 _{, the conductance G 2} has a non-zero value. Since no leak has occurred in the leak detection unit U having unit numbers N from 3 to m-1, the slope of the VI characteristic is constant as shown in FIG. 16, and the total conductance [G] is shown in FIG. ₁ + ... + G ₃ ] to [G ₁ + ... + G _m-1 ] are constant at _{G 2.} Then, as shown in FIG. 18, leak detection unit m-1 unit number N from _{3 [U 3, U k +} 2] ~ [U k-1, U n-1] the conductance _G 3 ~G _m of _-1 is all zero.

Then, similarly to the previously described, as shown in FIG. 18, leak detection unit _{[U k,} U _n] of the unit number N m becomes conductance G _m is not zero the value of the unit number N is m + 1 The conductance G _{m + 1} of the leak detection unit [U _{k + 1} , _{Un + 1} ] becomes zero.

Determination unit 90 compares each conductance G ₁ from the calculated unit number ₁ m + 1 ~G m + 1 with a predetermined threshold value, the conductance G 2 is larger than a predetermined threshold, m the leakage of the generated unit number N Specified as.

The specific operation of the unit number N in which the leak has occurred when the leak has occurred in the leak detection unit U of the two unit numbers N has been described above, but the leak has occurred in the three or more unit numbers N. The specific operation of the unit number N in the case is the same as the above-mentioned specific operation.

In the specific operation described above, the input voltage value is swept by one power supply 81 and one determination unit 90, the leak detection unit U is made conductive in the order of the unit number N, and the leak detection unit U of each unit number N is conducted. The conductance G of the above can be calculated, and the calculated conductance G can be compared with a predetermined threshold value to identify the unit number N in which the leak has occurred. This makes it possible to monitor the leakage of an object having a complicated shape including branching with a simple configuration.

Further, in the above specific operation, the change amount ΔI of the input current value is calculated from the two input current values corresponding to the two different voltage command values, but the same as the second determination operation described above, the same. A voltage sensor for detecting the input voltage value of the starting end 41 may be provided to detect the input voltage value, and the input voltage value detected by the voltage sensor may be used instead of the voltage command value. In this case, the amount of change ΔI of the input current value is calculated from the two input current values corresponding to the two different input voltage values.

_{In the above description of the specific operation, the total conductance [G 1} + ... + G _m-1 ] in the state where the leak detection unit U having the unit number N from 1 to m-1 is in a conductive state and the unit number N are Calculate _{the conductance G m} of the leak detection unit U having the unit number N m from the difference from _{the total conductance [G 1} + ... + G _m ] when the leak detection unit U from 1 to m is in the conductive state. It has been described as, may calculate the conductance G _m of leak detection unit U unit number m by the calculation method other than the calculation method.

_{For example, the total conductance [G 1} + ... + G _Nend ] when the leak detection unit U whose unit number N is 1 to Nend is in a conductive state, and the leak detection unit whose unit number N is 1 to m-1. _{From the difference from the total conductance [G 1} + ... + G _m-1 ] when U is in a conductive state, when the leak detection unit U whose unit number N is from m to Nend is virtually in a conductive state. Calculate the total conductance [G _m + ... + G _Nend]. Further, the difference between the total conductance [G ₁ + ... + G _{Nend ] and the total conductance [G 1} + ... + G _m ] when the leak detection unit U having the unit number N from 1 to m is in a conductive state. _{Calculates the total conductance [G m + 1} + ... + G _Nend ] when the leak detection unit U whose unit number N is from m to Nend is virtually in a conductive state. _{Then, G m} may be calculated from the difference between the total conductance [G _m + ... + G _Nend ] and the total conductance [G _{m + 1} + ... + G _Nend].

<Structure of the leak detection device 200 of the second embodiment>
The configuration of the leak detection device 200 of the second embodiment will be described with reference to FIGS. 19 to 21 below. The same parts as those of the leak detection device 100 described above with reference to FIGS. 1 to 18 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 19, the leak detection device 200 of the present embodiment is a constant voltage element D ₆ included in the node ND _{6 of the leak detection unit U 6} constituting the branch start end 51 of the branch leak detection unit 50. The rising voltage value is 4Vf, which is four times the rising voltage Vf of the other constant voltage element D. As described above, the three leak detection units U ₁ , U ₂ , and U ₆ are connected in series from the start end 41 of the trunk leak detection unit 40 to the leak detection unit U _6. Therefore, the integrated voltage value from the start end 41 to the leak detection unit U ₆ is Vf + Vf + 4Vf = 6Vf. The integrated voltage value from the start end 41 to the leak detection unit U _{7 is 7} Vf, and the integrated voltage value from the start end 41 to the leak detection unit U _{8 is 8} Vf. Further, as in the case of the liquid leakage detection device 100 described above, _{the integrated voltage values from the start end 41 to the liquid leakage detection units U 1} , U ₂ , U ₃ , U ₄ , and U ₅ are Vf, 2Vf, 3Vf, and 4Vf, respectively. It becomes 5Vf.

The unit numbers N are assigned in the order of the leakage detection units U ₁ , U ₂ , U ₃ , U ₄ , U ₅ , U ₆ , U ₇ , and U ₈ in ascending order of the integrated voltage value. Thus, the unit number N is 1 the leak detection unit _{U 1,} unit number N is a leak detection unit _{U 2,} leak detection unit _{U 3} of unit number N is 3, or less, leak detection unit _U 4, The _{unit numbers N of U 5} , U ₆ , U ₇ , and U ₈ are 4 to 8, respectively.

As described above, in the liquid leakage detection device 200 of the present embodiment, one unit number N corresponds to one liquid leakage detection unit U. Therefore, even in a configuration in which the branch leak detection unit 50 is branched from the trunk leak detection unit 40, the unit number N in which the leak has occurred is specified by the same method as the leak detection device 100 described above. Therefore, the leak detection unit U in which the leak has occurred can be identified.

<Specific operation of the leak detection unit U where leak has occurred>
Next, the specific operation of the liquid leakage detection unit U of the liquid leakage detection device 200 will be described with reference to FIGS. 20 and 21. 20 and 21 are generalized reference numerals of the system diagram shown in FIG. 19 for the purpose of explaining the operation of specifying the leak detection unit of the leak detection device 200, as in FIGS. 11 and 15 described above. be. In Figure 20 and 21, stem leakage detection unit 40 is obtained by connecting the leak detection unit _{U 1 ~U k +} 1 in series. Further, the branch leak detection unit 50 is a branch leak detection unit U _{k + 2 to} U _{m + 1} connected in series. Branch branch leak detection unit 50 start 51 is connected to the leak detection zone 30 of the leak detection unit U ₂ via the branch line 60. The number of liquid leakage detection units U [(k + 1) -2] connected to the terminal side of the _{liquid leakage detection unit U 2} of the trunk liquid leakage detection unit 40, and the liquid leakage detection unit constituting the branch liquid leakage detection unit 50. It is the same as the number of U [(m + 1)-(k + 2) + 1]. Each leak detection unit U is assigned a unit number N in the same order as described above. Leak detection unit U ₁ of the unit number N is 1, the unit number N of leak detection unit U ₂ 2, the unit number N of leak detection units U ₃ 3, unit number N of leak detection units U _k is k, leak detection unit _{U k + 1} of the unit number N is k + 1, leak detection unit _{U k + 2} of the unit number N is k + 2, unit number N of leak detection unit _{U m} is m, leak detection unit _{U m + 1} of the unit number N is m + 1. Here, k and m are natural numbers, and k <k + 1 <k + 2 <m-1 <m <m + 1.

Therefore, in the leak detection device 200 shown in FIGS. 20 and 21, when the input voltage value of the start end 41 is increased, each leak detection unit U has the leak detection units U ₁ and U _{2 in the order of the unit number N.} , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _m , U _{m + 1} conduct in this order.

Similar to the specific operation of the unit number N of the liquid leakage detection device 100 described above, the determination unit 90 conducts the liquid leakage detection unit U in the order of the unit number N, and the unit number N is leakage from 1 to m-1. _{Total conductance [G 1} + ... + G] with the liquid detection units U ₁ , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 in a conductive state. _{m-1 ] and leak detection units U 1} , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , with unit numbers N from 1 to m. calculating a conductance G _m of leak detection units U _m from the difference between the total conductance _{[G 1 + ·· + G m} ] in a state in which the U _m conductive, compares the calculated conductance G _m with a predetermined threshold value Then, the leak detection unit U in which the leak has occurred is identified.

<Details of specific operation of the leak detection unit U where leak has occurred>
The determination unit 90 sweeps the voltage value command value from zero to the standby voltage value V ₀ along the line c in FIG. 7, and each time the conduction range expands in the order of the unit number N, the liquid leakage detection unit U in the conduction range The total conductance value ΣG is calculated, and each conductance G of the leak detection unit U of each unit number is calculated from the difference from the total conductance value calculated in the previous conduction range. Leak detection unit _U 1 of the m-1 from unit number _{1, U 2, U 3 ··} U k-1, U k, U k + 1, U k + 2, leakage in · · _{U m-1} has not occurred Therefore, as shown in FIG. 12 _{, the input current value is zero until the input voltage value reaches V m} , and the conductance G of each unit number N calculated as shown in FIG. 13 is all zero. There is.

The determination unit 90 sweeps the voltage command value from m × Vf to a value slightly smaller than (m + 1) × Vf, and sweeps the input voltage value from m × Vf to a value slightly smaller than (m + 1) × Vf. During this period, the leak detection units U ₁ , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _m, whose unit numbers N are 1 to m, are conducting. It is within the range (conduction range _Am ). During this time, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the amount of change ΔI of the input current value is calculated from the detected input current value, and the leak detection units U ₁ , U ₂ , U ₃ ... U _k-1 , U whose unit number N, which is the conduction range, is 1 to m. Calculate the total value [G ₁ + _... + G _m ] = ΔI / ΔV of _{the conductances of k} , U _{k + 1} , U _{k + 2} , ... U _m-1 , and U _m.

_{Since a leak has occurred in the leak detection unit U m} whose unit number N is m, as shown in FIG. 12, the change in the input current value while the input voltage value changes by ΔV is not zero. [G ₁ + _... + G _m ] = ΔI / ΔV is a non-zero value. Determination unit 90 _obtains the values of _{G m} by subtracting the previously calculated from _{[G 1 + ··· + G m} ] [G 1 + ··· + G m-1].

The determination unit 90 sweeps the voltage command value from (m + 1) × Vf to a value slightly smaller than (m + 2) × Vf, and sweeps the input voltage value from (m + 1) × Vf to a value slightly smaller than (m + 2) × Vf. do. _{During this period, the leak detection units U 1} , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _m , U with unit numbers N from 1 to m + 1. _{m + 1} is the conduction range (conduction range A _{m + 1} ). During this time, the determination unit 90 detects with the current sensor 82 two input current values corresponding to the two voltage command values in which the difference between the voltage command values is ΔV. Then, the amount of change ΔI of the input current value is calculated from the detected input current value, and the leak detection units U ₁ , U ₂ , U ₃ ... U _k-1 , U whose unit number N, which is the conduction range, is 1 to m + 1. Calculate the total value [G ₁ + _... + G _{m + 1} ] = ΔI / ΔV of _{the conductances of k} , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _m , and U _{m + 1.}

_{Since no leak has occurred in the leak detection unit U m + 1} having the unit number N of m + 1, as shown in FIG. 12, the change of the input current value while the input voltage value changes by ΔV is determined by the unit number N. Leakage detection units from 1 to m U ₁ , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _m are the conduction range (conduction range _Am ). It is the same as the case of, and the inclination of the VI characteristic is also the same. Therefore, [G ₁ + _... + G _{m + 1} ] = ΔI / ΔV has the same value as _{G m.} The determination unit 90 subtracts _{[G 1} + _... + G _m ] = G _m calculated earlier from _{[G 1} + _... + G _{m + 1} ] = G _m to obtain a value of _{G m + 1 = 0.}

_{Leakage detection units U 1} , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 whose unit number N calculated as described above is from 1 to m + 1. , U _m , U _{m + 1} conductances G _{1 to} G _{m + 1 are G m} having a non-zero value only for _{the leak detection unit U m} in which the unit number N where the leak has occurred is m, as shown in FIG. , Other conductance G of each unit number N leak detection unit U ₁ , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 , U _{m + 1.} It becomes zero.

_{The determination unit 90 compares each conductance G 1 to} G _{m + 1} of each leak detection unit U of each calculated unit number with a predetermined threshold value, and leaks m when the conductance G is larger than the predetermined threshold value. Specify as unit number N. As described above, in the liquid leakage detection device 200, one unit number N corresponds to one liquid leakage detection unit U. Therefore, by specifying the unit number N, it is possible to specify the leak detection unit U in which the leak has occurred at the same time.

Next, as shown in FIG. 21, leaks occur in _{the leak detection unit U 2} of unit number 2 of the trunk leak detection unit 40 _{and the leak detection unit U m} of unit number m of the branch leak detection unit 50. The specific operation of the leak detection unit U in which the leak has occurred will be described.

Since the unit number N is not leakage in leak detection unit U ₁ of 1 occurs, a G 1 _{= 0.} Since a leak has occurred in _{the leak detection unit U 2} having the unit number N 2 _{, the conductance G 2} has a non-zero value. _{Leakage detection units U 3} ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 with unit numbers N from 3 to m-1 have no leaks, so FIG. 16 As shown in, the gradient of the VI characteristic is constant, and as shown in FIG. 17, the total conductance [G ₁ + ... + G ₃ ] to [G ₁ + ... + G _m-1 ] is constant at _{G 2.} Become. Then, as shown in FIG. 18, the conductances _{of the leak detection units U 3} ... U _k-1 , U _k 1, U _{k + 1} , U _{k + 2} , ... U _m-1 , whose unit numbers N are 3 to m-1. G _{3 to} G _m-1 are all zero.

Then, as described above, as shown in FIG. 18, the conductance G _{m of the leak detection unit U m} having the unit number N m is a non-zero value, and the leak detection unit U having the unit number N m + 1. conductance _{G m + 1} of the _{m + 1} is zero.

The determination unit 90 of the unit numbers 1 to m-1 of the leak detection units U ₁ , U ₂ , U ₃ ... U _k-1 , U _k , U _{k + 1} , U _{k + 2} , ... U _m-1 calculated. Each conductance G _{1 to} G _{m + 1} is compared with a predetermined threshold value, and 2, m in which the conductance G is larger than the predetermined threshold value is specified as the unit number N in which the leak has occurred. Since one specified unit number N corresponds to one leak detection unit U, by specifying the unit number N, it is possible to specify the leak detection unit U in which the leak has occurred at the same time.

The specific operation of the unit number N in which the leak has occurred when the leak has occurred in the leak detection unit U of the two unit numbers N has been described above, but the leak has occurred in the three or more unit numbers N. The specific operation of the unit number N in the case is the same as the above-mentioned specific operation.

The leak detection device 200 described above is configured such that one unit number N corresponds to one leak detection unit U. Therefore, even in a configuration in which the branch leak detection unit 50 is branched from the trunk leak detection unit 40, the leak detection unit U in which the leak has occurred is specified by one power supply 81 and one determination unit 90. Can be done. This makes it possible to identify the location of leakage in an object having a complicated shape including branching and the like with a simple configuration.

<Leakage detection device 300 of the third embodiment>
Next, the configuration of the leak detection device 300 of the third embodiment will be described with reference to FIG. 22. The same parts as those of the leak detection device 100 described above with reference to FIGS. 1 to 18 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 22, leakage detecting device 300, the node of the leak detection unit U ₆ constituting the branch starting end 51 of the branch leak detection unit 50 of the leakage detection apparatus 100 described with reference to FIG. 1 ND The rising voltage value of the constant voltage element D _{6 included in 6} is 2Vf, which is twice the rising voltage Vf of the other constant voltage element D. As described above, the three leak detection units U ₁ , U ₂ , and U ₆ are connected in series from the start end 41 of the trunk leak detection unit 40 to the leak detection unit U _6. Therefore, the integrated voltage value from the start end 41 to the leak detection unit U ₆ is Vf + Vf + 2Vf = 4Vf. The integrated voltage value from the start end 41 to the leak detection unit U ₇ is 5 Vf, and the integrated voltage value from the start end 41 to the leak detection unit U ₈ is 6 Vf. Further, as in the case of the liquid leakage detection device 100 described above, _{the integrated voltage values from the start end 41 to the liquid leakage detection units U 1} , U ₂ , U ₃ , U ₄ , and U ₅ are Vf, 2Vf, 3Vf, and 4Vf, respectively. It becomes 5Vf.

Unit number N, since the integrated voltage value from the start 41 (= ΣVf) are assigned in the ascending order, the unit number N of leak detection unit U ₁ of the integrated voltage value is smallest Vf is 1, the accumulated voltage The unit number of the 2Vf leak detection unit U ₂ is 2, the unit number of the leak detection unit U ₃ with an integrated voltage value of 3Vf is 3, and the unit number of the leak detection units U ₄ and U ₆ with an integrated voltage value of 4 Vf. N is 4, the unit number N of the leak detection units U ₅ and U _{7 having} an integrated voltage of 5 Vf is 5, and the unit number N of the leak detection unit U ₈ having an integrated voltage value of 6 Vf is 6.

As the input voltage is increased, the leak detection units U ₁ , U ₂ , and U ₃ are sequentially conducted, and then the leak detection units U ₄ , U ₆ , and the leak detection units U ₅ , U ₇ . The two leak detection units U are conducting at the same time. The liquid leakage determination operation of the liquid leakage detection device 300 and the specific operation of the unit number N in which the liquid leakage has occurred are described in FIG. 1 first, except that the conduction order of the liquid leakage detection unit U when increasing the input voltage is different. It is the same as each operation of the leak detection apparatus 100 described with reference to.

<Leakage detection device 400 of the fourth embodiment>
Next, the configuration of the leak detection device 400 of the fourth embodiment will be described with reference to FIG. 23. The same parts as those of the leak detection devices 100 and 200 described above with reference to FIGS. 1 to 21 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 23, leakage detector 400, the node of the leak detection unit U ₆ constituting the branch starting end 51 of the branch leak detection unit 50 of the leakage detection apparatus 100 described with reference to FIG. 1 ND The rising voltage value of the constant voltage element D _{6 included in 6} is 1.5 Vf, which is 1.5 times the rising voltage Vf of the other constant voltage element D. As described above, the three leak detection units U ₁ , U ₂ , and U ₆ are connected in series from the start end 41 of the trunk leak detection unit 40 to the leak detection unit U _6. Therefore, the integrated voltage value from the start end 41 to the leak detection unit U ₆ is Vf + Vf + 1.5Vf = 3.5Vf. The integrated voltage value from the start end 41 to the leak detection unit U ₇ is 4.5 Vf, and the integrated voltage value from the start end 41 to the leak detection unit U ₈ is 5.5 Vf. Further, as in the case of the liquid leakage detection device 10 described above, _{the integrated voltage values from the start end 41 to the liquid leakage detection units U 1} , U ₂ , U ₃ , U ₄ , and U ₅ are Vf, 2Vf, 3Vf, and 4Vf, respectively. It becomes 5Vf.

Unit number N, since the integrated voltage value from the start 41 (= ΣVf) are assigned in the ascending order, the unit number N of leak detection unit U ₁ of the integrated voltage value is smallest Vf is 1, the accumulated voltage The unit number of the 2Vf leak detection unit U ₂ is 2, the unit number of the leak detection unit U ₃ with an integrated voltage value of 3Vf is 3, and the unit number N of the _{liquid leakage detection unit U 6 with an integrated voltage value of 3.5Vf.} 4, leak detection unit _{U 4} unit number N of the integrated voltage 4Vf 5, unit number N of the integrated voltage value is leak detection unit _{U 7} of 4.5Vf 6, leak detection integrated voltage 5Vf The unit number N of the unit U ₅ is 7, and the unit number N of the liquid leakage detection unit U ₈ having an integrated voltage value of 5.5 Vf is 8. In this way, in the liquid leakage detection device 400, the unit number N is alternately attached by the trunk liquid leakage detection unit 40 and the branch liquid leakage detection unit 50.

In the liquid leakage detection device 400, as in the liquid leakage detection device 200, one unit number N corresponds to one liquid leakage detection unit U. Therefore, even in a configuration in which the branch leak detection unit 50 is branched from the trunk leak detection unit 40, the unit number N in which the leakage has occurred can be specified by specifying the unit number N in which the leakage has occurred, as in the case of the leakage detection device 200 described above. At the same time, the leak detection unit U in which the leak has occurred can be identified.

The specific operation of the liquid leakage detection unit U in which the liquid leakage has occurred in the liquid leakage detection device 400 is the same as the operation of the liquid leakage detection device 200 described above.

<Leakage detection device 500 of the fifth embodiment>
Next, the leak detection device 500 of the fifth embodiment will be described with reference to FIG. 24. The same parts as those of the leak detection device 100 described above with reference to FIGS. 1 to 18 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 24, leakage detecting device 500 includes a connection point 65 between the leak detection unit U ₂ branches starting 51 and Mikimo liquid detecting portion 40 of the branch leakage detecting unit 50, the ends of the connection point 65 is provided between the stem switch 45 provided between the leak detection unit U ₃ stem leakage detection unit 40 connected to the side, the branch starting end 51 of the connection point 65 and Edamo liquid detecting unit 50 It has a branch switch 55 and. The trunk switch 45 and the branch switch 55 are connected to the determination unit 90, and are turned on / off by a command from the determination unit 90.

In the first to third leak determination operations of the leak detection device 100 described above, it is possible to determine the occurrence of leak, but whether the trunk leak detection unit 40 has leaked or not. It is not possible for the branch leak detecting unit 50 to determine whether or not a leak has occurred. Further, in the specific operation of the unit number N in which the leak has occurred, the unit number N in which the leak has occurred can be specified, but the leak of the trunk liquid detection unit 40 to which the specific unit number N is attached. It is not possible to distinguish whether the leak is occurring in the detection unit U or the leak detection unit U of the branch leak detection unit 50.

Therefore, in the liquid leakage detection device 500, normally, the trunk switch 45 and the branch switch 55 are turned on, and when it is determined by the liquid leakage determination operation that a leak has occurred, the determination unit 90 determines the trunk switch 45 and the branch switch. By switching between 55 and 55, it is determined whether the location where the leakage occurs is located in the trunk leakage detection unit 40 or the branch leakage detection unit 50.

When the input current value detected by the current sensor 82 becomes zero when the branch switch 55 is turned off, the determination unit 90 determines that the leakage has occurred in the branch leakage detection unit 50. Further, when the input current value becomes zero when the trunk switch 45 is turned off, it is determined that the leak is generated on the terminal side of the connection point 65 of the stem leak detection unit. If the input current value does not become zero even when both the branch switch 55 and the trunk switch 45 are turned off, it is determined that the leak is generated in the trunk leak detection unit 40 on the starting end side of the connection point 65. do.

Similarly, when the determination unit 90 identifies the unit number N in which the liquid leak occurs, and the input current value detected by the current sensor 82 becomes zero when the branch switch 55 is turned off, the leak occurs. It is determined that the liquid has leaked in the leak detection unit U of the branch leak detection unit 50 to which the specified unit number N is attached. If the input current value becomes zero when the trunk switch 45 is turned off, the leak is leaked by the leak detection unit U of the trunk leak detection unit 40 to which the specified unit number N is attached. It is determined that liquid is generated.

In this way, the leak detection device 500 of the present embodiment can determine whether the location where the leak is generated is located in the trunk leak detection unit 40 or the branch leak detection unit 50. With a simple configuration, the area where leakage has occurred can be narrowed down.

<Leakage detection device 600 of the sixth embodiment>
Next, the leak detection device 600 of the sixth embodiment will be described with reference to FIG. 25. The same parts as those of the leak detection device 100 described above with reference to FIGS. 1 to 18 are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 25, in the liquid leakage detection device 600, the liquid leakage detection band 30 is composed of a pair of covered electric wires 33, and a non-detection region in which a current does not flow even if a liquid leaks in contact between them is partially a part. Includes.

The pair of terminal pins 14, 16 of the node ND ₁ of leak detection unit _{U 1} shown in FIG. 25, a pair of conductive lines 31 and 32 constituting the leak detection zone 30 is connected, a pair of conductive lines 31 A pair of covered electric wires 33 constituting a non-detection region are connected to the ends of the 32. The ends of the pair of covered electric wires 33 are connected to the pair of start end side terminals 13 and 15 of the node ND _{2 of the liquid leakage detection unit U 2.}

Further, a pair of coated electric wires 33 are connected to the pair of terminal side terminals 14 and 16 of the node ND ₃ of the liquid leakage detection unit U ₃ , and a pair of conductive wires 31 and 32 are connected to the ends of the pair of coated electric wires 33. It is connected. That is, a pair of conductive wires 31 and 32 are connected to the pair of terminal side terminals 14 and 16 of the node ND _{3 via a pair of covered electric wires 33, respectively.} Further, between the node ND ₅ node ND ₄ and leak detection unit U ₅ of leak detection unit U ₄ is leak detection comprising a non-detection region that consists of a pair of covered wires at the starting end side and the distal side It is connected by a band 30. Further, the end side terminal 14, 16 of the node ND ₅ of leak detection unit U _5, leak detection zone 30 comprises a non-detection region that consists of a pair of covered wire in the middle is connected.

Further, as shown in FIG. 25, in the liquid leakage detection device 600, the branch line 60 is composed of the covered electric wire 33. Further, as shown in FIG. 25 (a), a part of the branch line 60 may be composed of a pair of conductive wires 31 and 32, and the other part may be composed of a pair of covered electric wires 33.

As described above, the lengths of the conductive wires 31, 32, 61, and 62 are formed by forming a part of the leak detection band 30 or a part or the whole of the branch wire 60 which does not require monitoring of the leak with an inexpensive coated electric wire. The cost can be reduced by shortening the length.

<Leakage detection device 700 of the 7th embodiment>
Next, the leak detection device 700 of the seventh embodiment will be described with reference to FIGS. 26 to 29. As shown in FIG. 26, the leak detection unit 140 of the leak detection device 700 is a _{series of five leak detection units U 1 to} U 5, and the leak detection unit U ₂ and the leak detection unit U are connected in series. _A repeater 70 is connected in series with 3.

As shown in FIG. 27, the repeater 70 is a 4-terminal circuit having input terminals 71 and 72 and output terminals 73 and 74, and the voltage value V _out of the output terminals 73 and 74 is the voltage of the input terminals 71 and 72. A predetermined magnification a of the value V _in is set, and the current value I _{in of the input terminals 71 and 72 and the current value I out} of the output terminals 73 and 74 are kept the same.

As shown in FIG. 26, the input terminals 71 and 72 of the repeater 70 _{are connected to the end of the liquid leakage detection band 30 of the liquid leakage detection unit U 2} , and the output terminals 73 and 74 are the start ends of the liquid leakage detection unit U ₃ . It is connected to the side terminals 13 and 15. Therefore, the repeater 70 has the liquid leakage detection unit U connected to the output terminals 73 and 74 with the voltage value at the end of _{the liquid leakage detection unit U 2 connected to the input terminals 71 and 72 as the voltage value having a predetermined magnification a. Output to 3} and keep the current value flowing through the leak detection units U ₂ and U _{3 at a constant current value.}

The repeater 70 may have any electric circuit as long as it has the above-mentioned functions, but as an example, as shown in FIG. 28, a plurality of operational amplifiers 76 and an instrumentation amplifier 75 A voltage amplification unit 70A and a mirror circuit 70B may be realized by combining resistors 78.

As described above with reference to FIG. 5, the leak detection unit U conducts in the order of the unit number N each time the input voltage value applied to the start end 41 is increased by Vf. Therefore, in order to connect a large number of leak detection units U in series to form the leak detection unit 140 and to make all the leak detection units U conductive, a standby voltage value V ₀ applied to the start end 41 is connected in series. It is necessary that the number of leak detection units U connected to the above × Vf or more. However, the lower the standby voltage value V _0, the more advantageous in the design of each device. When the repeater 70 is sandwiched between the liquid leakage detection units 140 as in the liquid leakage detection device 700 of the present embodiment, the voltage value at the end of the _{liquid leakage detection unit U 2 on the start end side of the repeater 70 has a predetermined magnification a.} voltage value multiplied by is applied to the distal side of the leakage detection unit U ₃ repeater 70. Therefore, all the leak detection units U can be made conductive without increasing the standby voltage value V _{0 applied to the leak detection unit U 1} connected to the start end 41.

Further, since the repeater 70 holds the current value I _{in of the input terminals 71 and 72 and the current value I out} of the output terminals 73 and 74 in the same manner, the leakage detection connected in series via the repeater 70. The current value flowing through the unit U can be detected by the current sensor 82. Therefore, the leakage can be determined by the same determination operation as that of the leakage detection device 100.

Repeater 70, since the voltage value _{V out} of _the output terminals 73 and 74 with a predetermined magnification a voltage value _{V in} of the input terminals 71 and 72, as shown in FIG. 29, leakage of the distal side of the repeater 70 When a leak occurs in the liquid detection units U _{3 to} U ₅ , the rate of change of the current with respect to the input voltage value to the start end 41 is such that the leak is found in the leak detection units U ₁ and U _{2 on the start end side of the repeater 70.} When it occurs, it becomes larger than the rate of change of the current with respect to the input voltage value to the start end 41. Therefore, when the unit number N in which the leak has occurred is specified by the same method as the leak detection device 100, it is necessary to increase the voltage resolution of the power supply 81 so that a minute voltage change can be performed.

As described above, the liquid leakage detection device 700 can increase the number of liquid leakage detection units U that can be connected to the liquid leakage detection unit 140 by providing the repeater 70. As a result, a long leak detection unit 140 can be configured to detect leaks in a wider range. Further, it is possible to connect a large number of short-length leak detection units U to form a leak detection unit 140, narrow the identifiable leak range, and perform finer leak monitoring.

<Leakage detection device 800 of the eighth embodiment>
Next, the leak detection device 800 of the eighth embodiment will be described with reference to FIG. 30. The same parts as those of the leak detection device 100 described above with reference to FIGS. 1 to 18 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 30, in the liquid leakage detection device 800 _{, the branch line 60 is only connected to the liquid leakage detection unit U 2} of the trunk liquid detection unit 40, and the branch liquid detection unit is connected to the end of the branch line 60. 50 is not connected. As shown in FIG. 30A, the branch line 60 is composed of a pair of conductive lines 31 and 32, and the branch detection band 66 includes a detection region in which a current flows when a leak comes into contact between the conductive lines 31 and 32. However, as shown in FIG. 30 (b), a non-detection region partially composed of a pair of covered electric wires 33 may be included.

The liquid leakage detection unit U ₂ is a current when a liquid leak occurs in either the liquid leakage detection band 30 connecting the _{node ND 2} and the node ND _{3 or the branch detection band 66 branched from the liquid leakage detection band 30.} Flows, and the occurrence of liquid leakage at the branch line 60 can be detected.

With this configuration, it is possible to perform the leakage detection, such as branches of the short pipe at one leak detection unit U _2, performs leakage monitoring of objects of complex shape including a branch or the like with a simple structure Is possible.

<Leakage detection device 900 of the ninth embodiment>
Next, the leak detection device 900 of the ninth embodiment will be described with reference to FIG. 31. The leak detection device 900 is a combination of each part of the leak detection devices 100, 200, 300, 400, 500, 600, 700, 800 of each embodiment described so far according to the shape of the piping device 20. .. The piping device 20 is composed of a trunk pipe 21, a short branch pipe 22, and a long branch pipe 23.

_{The liquid leakage detection unit U 1} of the liquid leakage detection device 900 shown in FIG. 31 is a branch detection band capable of detecting the leakage of the branch pipe 22 like the liquid leakage detection device 800 described with reference to FIG. 30. It is a liquid leakage detection unit having 66. Unit number N of leak detection unit U ₁ is 1.

The leak detection unit U ₂ is connected to a branch leak detection unit 50 in _{which the leak detection units U 6} and U ₇ are connected in series, as in the leak detection device 100 described with reference to FIG. It is a leak detection unit. The leak detection unit U ₂ detects the leak in the long branch pipe 23. Further, the _{liquid leakage detection unit U 4} includes a non-detection region in which the liquid leakage detection band 30 is partially composed of a covered electric wire 33, as in the liquid leakage detection device 600 described with reference to FIG. 25.

As described above, by combining each part of the leak detection device 100, 200, 300, 400, 500, 600, 700, 800 of each embodiment described so far according to the shape of the piping device 20, a simple configuration can be obtained. It is possible to monitor the leakage of an object having a complicated shape including branching.

<Variations of constant voltage elements>
With reference to FIG. 32 will be described variation of the constant voltage element D _n. At reference to leakage detecting device described with 100 to FIG. 18, constant voltage element D _n is connected zener diodes 11a, and 11b to the anti-series, it is arranged so as to be interposed in one of the connecting line 12 However, the present invention is not limited to this, and may be configured as shown in FIGS. 32 (a) to 32 (f).

As shown in FIG. 32 (a), the connection directions of the Zener diodes 11a and 11b may be connected in anti-series in the opposite direction to the state shown in FIG. Further, as shown in FIG. 32 (b), the connection line 12 may be arranged on the side opposite to the side shown in FIG. Further, as shown in FIGS. 32 (c) and 32 (d), one Zener diode 11a and 11b are arranged in the same direction on both connection lines 12, respectively, and a current flow when a liquid leak occurs. The two Zener diodes 11a and 11b may be in anti-series with respect to the above. Further, as shown in FIG. 32 (e), the Zener diode 11a may be interposed only in one of the connection lines 12. In this case, the power supply 81 may be configured by using a DC power supply. Further, instead of using the Zener diodes 11a and 11b, a constant voltage element circuit 18 in which an electric circuit having a voltage-current characteristic as shown in FIG. 3 is composed of an IC or the like may be used.

Thus, by variously changing the arrangement of the constant voltage element D _n nodes ND _n in accordance with the liquid to be detected, it is possible to perform the leakage detection in accordance with the liquid to be detected.

11a, 11b Zener diode, 12 connection line, 13,15 start end side terminal, 14,16 end side terminal, 18 constant voltage element circuit, 20 piping device, 21 trunk pipe, 22,23 branch pipe, 30 leak detection band, 31, 32, 61, 62 Conductive wire, 31e, 32e end, 33 covered wire, 35 leak part, 40 trunk leak detector, 41 start end, 42 end, 45 trunk switch, 50 branch leak detector, 51 Branch start end, 52 branch end, 55 branch switch, 60 branch line, 63, 64, 65 connection point, 66 branch detection band, 70 repeater, 70A voltage amplifier, 70B mirror circuit, 71,72 input terminal, 73,74 Output terminal, 75 instrument amplifier, 76 amplifier, 78 resistor, 81 power supply, 82 current sensor, 90 judgment unit, 91 CPU, 92 memory, 93 input interface, 94 output interface, 95 data bus, 100, 200, 300, 400 , 500, 600, 700, 800, 900 Leakage detector, 140 Leakage detector, D, D _{1 to} D ₈ , D _k , D _m , D _n constant voltage element, N unit number, ND, ND ₁ to _{ND 8,} ND m, ND _{n nodes, U, U 1 ~U 8,} U k, U m, U n leak detection unit.

Claims (23)

It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A trunk leak detection unit in which one or more of the leak detection units including a node having a conductive constant voltage element are connected in series, and a trunk leak detection unit.
A branch leak detection unit in which one or more of the leak detection units are connected in series,
The power supply connected to the start end of the trunk liquid detection unit,
A current detection unit that detects the input current value at the beginning of the trunk liquid detection unit, and a current detection unit.
A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided.
The branch start end of the branch leak detection unit is connected to any one or more of the trunk leak detection units of the leak detection unit.
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value .
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit fluctuates the voltage command value output to the power supply before and after the standby voltage value, and fluctuates the input voltage value of the stem leak detection unit before and after the standby voltage value.
At least one leak detection unit by comparing a conductance or resistance value calculated from the voltage command value or the input voltage value and the input current value detected by the current detector with a predetermined threshold value. To determine that a leak has occurred in
A leak detection device characterized by. It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A trunk leak detection unit in which one or more of the leak detection units including a node having a conductive constant voltage element are connected in series, and a trunk leak detection unit.
A branch leak detection unit in which one or more of the leak detection units are connected in series,
The power supply connected to the start end of the trunk liquid detection unit,
A current detection unit that detects the input current value at the beginning of the trunk liquid detection unit, and a current detection unit.
A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided.
The branch start end of the branch leak detection unit is connected to any one or more of the trunk leak detection units of the leak detection unit.
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value.
Each of the leak detection units has a unit number in ascending order of the integrated voltage value of the energization voltage value of each constant voltage element included in each of the leak detection units connected in series from the start end to the leak detection unit. Is attached,
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit sweeps the voltage command value output to the power supply, sweeps the input voltage value of the trunk leak detection unit, and conducts each of the leak detection units in the order of the unit number.
By comparing the conductance or resistance value calculated from the voltage command value or the input voltage value with the input current value detected by the current detection unit and a predetermined threshold value, the leak detection of the unit number in the conducting state is detected. Determining that a leak has occurred in the leak detection unit having at least one unit number among the units.
A leak detection device characterized by. It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A trunk leak detection unit in which one or more of the leak detection units including a node having a conductive constant voltage element are connected in series, and a trunk leak detection unit.
A branch leak detection unit in which one or more of the leak detection units are connected in series,
The power supply connected to the start end of the trunk liquid detection unit,
A current detection unit that detects the input current value at the beginning of the trunk liquid detection unit, and a current detection unit.
A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided.
The branch start end of the branch leak detection unit is connected to any one or more of the trunk leak detection units of the leak detection unit.
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value.
Each of the leak detection units has a unit number in ascending order of the integrated voltage value of the energization voltage value of each constant voltage element included in each of the leak detection units connected in series from the start end to the leak detection unit. Is attached,
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit sweeps the voltage command value output to the power supply, sweeps the input voltage value of the trunk leak detection unit, and conducts each of the leak detection units in the order of the unit number.
The input current value detected by the current detection unit when the range from the start end of the trunk liquid detection unit to the liquid leakage detection unit of one unit number is made conductive, and one of the ranges. The conductance of the leak detection unit with one unit number is calculated by using the input current value detected by the current detection unit when the range other than the leak detection unit of the unit number is made conductive. ,
By comparing the calculated conductance with a predetermined threshold value, the unit number of the leak detection unit in which the leak has occurred can be specified.
A leak detection device characterized by. The leak detection device according to any one of claims 1 to 3.
The node of the leak detection unit
A pair of start end terminals and
A pair of terminal terminals to which the pair of conductive wires are connected,
Comprises a pair of connection lines for connecting the distal terminal and the starting end side terminals in parallel,
The constant voltage element is arranged so as to be interposed between one or both connection lines.
A leak detection device characterized by. The liquid leakage detection device according to claim 2.
Each of the leak detection units has different integrated voltage values of the energization voltage values of the constant voltage elements included in the leak detection units connected in series from the start end to the leak detection unit. , The unit numbers are assigned in ascending order of the integrated voltage value.
The determination unit determines that a leak has occurred in at least one of the leak detection units in a conductive state.
A leak detection device characterized by. The liquid leakage detection device according to claim 3.
Each of the leak detection units has different integrated voltage values of the energization voltage values of the constant voltage elements included in the leak detection units connected in series from the start end to the leak detection unit. , The unit numbers are assigned in ascending order of the integrated voltage value.
The determination unit identifies the leak detection unit in which the leak has occurred.
A leak detection device characterized by. The leak detection device according to any one of claims 1 to 3.
The connection point between the branch start end of the branch leakage detection unit and the leakage detection unit of one of the trunk leakage detection units, and the other of the trunk leakage detection unit connected to the terminal side of the connection point. The trunk switch provided between the leak detection unit and
A branch switch provided between the connection point and the branch start end of the branch leak detection unit,
A leak detection device characterized by having. The liquid leakage detecting device according to claim 7.
The determination unit
By switching between the trunk switch and the branch switch, it is determined whether the location where the leakage occurs is located in the trunk leakage detection unit or the branch leakage detection unit.
A leak detection device characterized by. The liquid leakage detecting device according to any one of claims 1 to 8.
The leak detection band is composed of a pair of covered electric wires, and includes a non-detection region in which no current flows even if a leak comes into contact between them.
The node of the leak detection unit
A pair of start end terminals and
A pair of terminal terminals to which the pair of the conductive wires are connected directly or via a pair of covered wires, respectively.
Comprises a pair of connection lines for connecting the distal terminal and the starting end side terminals in parallel,
The constant voltage element is arranged so as to be interposed between one or both connection lines.
A leak detection device characterized by. The leak detection device according to any one of claims 1 to 9.
The branch start end of the branch liquid detection unit is connected to the liquid leakage detection unit of the trunk liquid detection unit via a pair of branch lines.
The pair of branch lines shall be composed of a pair of conductive lines through which an electric current flows when a leak comes into contact with the branch lines.
A leak detection device characterized by. The leak detection device according to any one of claims 1 to 9.
The branch start end of the branch liquid detection unit is connected to the liquid leakage detection unit of the trunk liquid detection unit via a pair of branch lines.
The pair of branch wires shall be composed of a pair of covered wires that do not allow current to flow even if a leak comes into contact with them.
A leak detection device characterized by. The leak detection device according to any one of claims 1 to 9.
The branch start end of the branch liquid detection unit is connected to the liquid leakage detection unit of the trunk liquid detection unit via a pair of branch lines.
A part of the pair of branch wires is composed of a pair of conductive wires to which a current flows when a leak comes into contact between them, and the other part is a pair of coated electric wires to which a current does not flow even if a leak comes into contact between them. Being configured,
A leak detection device characterized by. The liquid leakage detecting device according to any one of claims 1 to 12.
A repeater arranged between the leak detection units connected in series with the trunk leak detection unit or between the leak detection units connected in series with the branch leak detection unit. Including
In the repeater, the voltage value of the output terminal is set to a predetermined magnification of the voltage value of the input terminal, and the current value of the input terminal and the current value of the output terminal are kept the same.
A leak detection device characterized by. It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A leak detection unit in which one or a plurality of leak detection units including a node having a conductive constant voltage element are connected in series, and a leak detection unit.
The power supply connected to the start end of the liquid leakage detection unit,
A current detection unit that detects the input current value at the beginning of the liquid leakage detection unit, and a current detection unit.
A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided.
The one or more of the leak detection units comprises a pair of the conductive wires and includes a branch detection zone including a detection region in which a current flows when a leak comes into contact between the conductive wires.
The branch detection band is connected to the leak detection band or the node.
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value.
The node of the leak detection unit
A pair of start end terminals and
A pair of terminal terminals to which the pair of conductive wires are connected,
Includes a pair of connecting wires that connect the start end side terminal and the end end side terminal in parallel.
The constant voltage element is arranged so as to be interposed between one or both connection lines .
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit fluctuates the voltage command value output to the power supply before and after the standby voltage value, and fluctuates the input voltage value of the liquid leakage detection unit before and after the standby voltage value.
At least one leak detection unit by comparing a conductance or resistance value calculated from the voltage command value or the input voltage value and the input current value detected by the current detector with a predetermined threshold value. To determine that a leak has occurred in
A leak detection device characterized by. It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A leak detection unit in which one or a plurality of leak detection units including a node having a conductive constant voltage element are connected in series, and a leak detection unit.
The power supply connected to the start end of the liquid leakage detection unit,
A current detection unit that detects the input current value at the beginning of the liquid leakage detection unit, and a current detection unit.
A determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit is provided.
The one or more of the leak detection units comprises a pair of the conductive wires and includes a branch detection zone including a detection region in which a current flows when a leak comes into contact between the conductive wires.
The branch detection band is connected to the leak detection band or the node.
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value.
The node of the leak detection unit
A pair of start end terminals and
A pair of terminal terminals to which the pair of conductive wires are connected,
Includes a pair of connecting wires that connect the start end side terminal and the end end side terminal in parallel.
The constant voltage element is arranged so as to be interposed between one or both connection lines.
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit sweeps the voltage command value output to the power supply, sweeps the input voltage value of the leak detection unit, and conducts each of the leak detection units in the order in which they are connected to the start end.
The input current value detected by the current detection unit when the range from the start end of the liquid leakage detection unit to one of the leakage detection units is made conductive, and one of the above ranges, the leakage detection. The conductance of one of the leak detection units is calculated by using the input current value detected by the current detection unit when the range other than the unit is made conductive.
By comparing the calculated conductance with a predetermined threshold value, the leak detection unit in which the leak has occurred can be identified.
A leak detection device characterized by. The liquid leakage detecting device according to claim 14 or 15.
The leak detection band is composed of a pair of covered electric wires, and includes a non-detection region in which no current flows even if a leak comes into contact between them.
The terminal on the terminal side of the node of the liquid leakage detection unit is connected to the pair of conductive wires directly or via a pair of covered electric wires.
A leak detection device characterized by. The liquid leakage detecting device according to claim 16.
The branch detection band is composed of a pair of covered electric wires, and includes a non-detection region in which no current flows even if a leak comes into contact between them.
A leak detection device characterized by. It consists of a pair of conductive wires, and when the applied voltage reaches a predetermined voltage value, it is connected to the leak detection band including the detection region where current flows when the leak contacts between the conductive wires and the leak detection band. A leak detection unit in which one or a plurality of leak detection units including a node having a conductive constant voltage element are connected in series, and a leak detection unit.
The power supply connected to the start end of the liquid leakage detection unit,
A current detection unit that detects the input current value at the beginning of the liquid leakage detection unit, and a current detection unit.
A liquid leakage detection device including a determination unit for determining the occurrence of liquid leakage from the input current value detected by the current detection unit.
Includes a repeater located between the leak detection units connected in series with the leak detector.
In the repeater, the voltage value of the output terminal is set to a predetermined magnification of the voltage value of the input terminal, and the current value of the input terminal and the current value of the output terminal are kept the same.
The leak detection unit is
Each of the leak detection units has the characteristic of conducting conduction according to the input voltage value.
The node of the leak detection unit
A pair of start end terminals and
A pair of terminal terminals to which the pair of conductive wires are connected,
Includes a pair of connecting wires that connect the start end side terminal and the end end side terminal in parallel.
The constant voltage element is arranged so as to be interposed between one or both connection lines.
A leak detection device characterized by. The liquid leakage detecting device according to claim 18.
The leak detection band is composed of a pair of covered electric wires, and includes a non-detection region in which no current flows even if a leak comes into contact between them.
The terminal on the terminal side of the node of the liquid leakage detection unit is connected to the pair of conductive wires directly or via a pair of covered electric wires.
A leak detection device characterized by. The liquid leakage detection device according to claim 18 or 19.
The power supply applies a standby voltage having a predetermined voltage value to the starting end of the liquid leakage detection unit.
The determination unit determines the occurrence of liquid leakage in at least one liquid leakage detection unit by comparing the input current value detected by the current detection unit with a predetermined threshold value.
A leak detection device characterized by. The liquid leakage detection device according to claim 18 or 19.
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit fluctuates the voltage command value output to the power supply before and after the standby voltage value, and fluctuates the input voltage value of the liquid leakage detection unit before and after the standby voltage value.
At least one leak detection unit by comparing a conductance or resistance value calculated from the voltage command value or the input voltage value and the input current value detected by the current detector with a predetermined threshold value. To determine that a leak has occurred in
A leak detection device characterized by. The liquid leakage detection device according to claim 18 or 19.
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit sweeps the voltage command value output to the power supply, sweeps the input voltage value of the leak detection unit, and conducts each of the leak detection units in the order in which they are connected to the start end.
By comparing the conductance or resistance value calculated from the voltage command value or the input voltage value with the input current value detected by the current detection unit and a predetermined threshold value, the liquid leakage detection unit in the conductive state is included. , Determining that a leak has occurred in at least one of the leak detection units.
A leak detection device characterized by. The liquid leakage detection device according to claim 18 or 19.
The power supply outputs a voltage corresponding to the voltage command value input from the determination unit.
The determination unit sweeps the voltage command value output to the power supply, sweeps the input voltage value of the leak detection unit, and conducts each of the leak detection units in the order in which they are connected to the start end.
The input current value detected by the current detection unit when the range from the start end of the liquid leakage detection unit to one of the leakage detection units is made conductive, and one of the above ranges, the leakage detection. The conductance of one of the leak detection units is calculated by using the input current value detected by the current detection unit when the range other than the unit is made conductive.
By comparing the calculated conductance with a predetermined threshold value, the leak detection unit in which the leak has occurred can be identified.
A leak detection device characterized by.

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