JP4743036B2 - Leak sensor device - Google Patents

Description

  The present invention relates to a leakage sensor device that detects liquid leaking from equipment such as a production line, and in particular, the amount of phase change in which the current flowing through parallel electric wires arranged in parallel along the pipeline or under the floor of a semiconductor factory changes due to leakage. The present invention relates to a liquid leakage sensor device that detects a liquid leakage and identifies a liquid leakage position.

  As disclosed in "Patent Document 1" (leakage detection device), a conventional leakage sensor device has a detection line composed of first and second conductors that are insulated from each other and arranged substantially in parallel. A detection line as a position detection conductor having at least a second conductor having a uniform conductor resistance in the length direction or every section, and connected to one end of the detection line, the first conductor side being the upstream side As a constant current power source for supplying a constant current, a voltage measuring means, and a judging means, and from the leak position of the position detection conductor to the near end or the far end by a constant current supplied from the constant current power supply at the time of leak The voltage drop value is measured by the voltage measuring means, and the determining means calculates the leak position from the measured voltage value. The constant current power source has a duty ratio equal to or less than a predetermined value, and the peak value is A pulse power supply that generates a constant pulse current. Voltage measuring means is composed of a pulse voltage measuring means for measuring the peak value of the pulse voltage.

As described above, the constant current power source is a pulse power source that generates a pulse current having a duty ratio equal to or less than a predetermined value and a constant peak value, and the voltage measuring unit is a pulse voltage measuring unit that measures the peak value of the pulse voltage; Therefore, the peak value of the pulse current is stabilized at a true value in a short time without causing the leakage of the liquid, and the position of the liquid leakage can be accurately measured.
Japanese Patent Laid-Open No. 7-113719 (refer to claim 1 and FIG. 4)

  However, since the leak sensor device disclosed in “Patent Document 1” (leak detector) generates a voltage drop from the leak position to the near end or the far end by a pulse current, the second conductor is long. Since it is composed of a plurality of resistors having a uniform conductor resistance in each direction or section, when detecting the leak position with high accuracy, a lot of resistors must be provided on the second conductor, There exists a subject which causes the increase in the number of parts of a resistor.

  In addition, the leak sensor device disclosed in “Patent Document 1” measures the voltage drop from the leak position to the near end or the far end, and therefore leaks from the far end to the near end of the second conductor. The conductor covered with the insulating layer which does not melt | dissolve is needed, and the conductor (wire material) covered with the insulating layer which does not melt | dissolve in one liquid leak is changed into the 1st and 2nd conductor ( Therefore, three wires are required, resulting in an increase in cost, and there is a problem that man-hours are required for laying the wire.

  Furthermore, the leak sensor device disclosed in “Patent Document 1” requires switch means for switching and measuring the voltage drop between the leak position and the near end or far end of the second conductor, There is also a problem that an operation for switching the switch means occurs.

  The present invention has been made to solve such a problem, and its object is to apply a sinusoidal high-frequency voltage between two parallel wire lines and measure the phase of the initial current at which no leakage occurs. Detecting the phase of the leakage current that flows through the electric line when leakage occurs, and pinpointing the leakage position from the amount of phase change that is the deviation between the leakage current phase and the initial current phase The object is to provide a possible liquid leakage sensor device.

In order to solve the above-described problems, a leak sensor device according to the present invention includes two parallel wires covered with an insulator, and the center of the insulator is formed with a continuous groove or an intermittent groove along the extending direction of the parallel wires. A leakage sensor that generates a capacitance between parallel wires due to leakage stored in a groove or bowl-shaped groove, and a high-frequency sine wave voltage applied to the power supply end of the leakage sensor. Detection / determination that detects the phase change amount of the high-frequency sine wave current flowing in the parallel wires based on the capacitance and determines the distance from the feeding end of the parallel wire to the leak occurrence position corresponding to the detected phase change amount And a detection / judgment means for supplying the high-frequency sine wave voltage to the feeding ends of the parallel wires and an initial state of flowing through the parallel wires in a liquid-free initial state. Current detector that detects current and converts it to sine wave voltage And a cancellation unit that adjusts and cancels the phase and amplitude of the sine wave voltage supplied from the reference voltage unit and the sine wave voltage supplied from the current detection unit, and the phase change amount of the leakage current that flows at the time of leakage The phase change detection unit to detect, the phase change from the phase change detection unit are integrated, and a phase-voltage conversion unit that outputs a DC voltage, and a high-frequency sine wave voltage is generated from the reference clock, and the phase change And a clock processor for generating a trigger pulse for detecting the quantity .

The liquid leakage sensor device according to the present invention covers two parallel electric wires with an insulator, and forms a continuous groove or intermittent groove along the extending direction of the parallel electric wire at the center of the insulator, thereby forming the continuous groove or intermittent groove. A leakage sensor that generates capacitance between parallel wires due to leakage stored in the battery, and a high-frequency sine wave voltage applied to the power supply end of the leakage sensor, and parallel based on the capacitance generated in the leakage sensor Detection / determination means for detecting a phase change amount from an initial current phase of a high-frequency sine wave current flowing in the electric wire, and determining a distance from a feeding end of the parallel wire corresponding to the detected phase change amount to a leakage occurrence position; Therefore, the leak sensor has a simple configuration in which parallel wires are covered with an insulator, generates a capacitance between the parallel wires due to the leak, and a high-frequency sine wave current corresponding to the distance of the parallel wires. Phase detection amount, and the detection / determination means is high. Since the phase change amount of the sinusoidal current of the wave is detected and this phase change amount is determined as the distance from the feeding end of the parallel wire to the leak occurrence position, the leak position is determined as a pin point on the parallel wire. Can do. Further, the detection / determination means according to the present invention detects a reference voltage unit that supplies a high-frequency sine wave voltage to the feeding end of the parallel wires, and an initial current that flows through the parallel wires in an initial state without leakage, A current detection unit that converts to a sine wave voltage, a cancellation unit that adjusts and cancels the phase and amplitude of the sine wave voltage supplied from the reference voltage unit and the sine wave voltage supplied from the current detection unit, and flows when the liquid leaks Phase change amount detection unit for detecting the phase change amount of the current at the time of leakage, phase-voltage conversion unit for integrating the phase change amount from the phase change amount detection unit and outputting it as a DC voltage, and a high frequency sine from the reference clock In addition to generating a wave voltage and a clock processing unit that generates a trigger pulse that detects the amount of phase change, the phase of the initial current without leakage flowing through the parallel line is canceled and output at a DC voltage of 0 v The phase change amount of leakage when the current extracted by the pulse width, by integrating the pulse width, it is possible to output a DC voltage corresponding to the phase variation amount.

  The parallel wire according to the present invention is characterized in that the far end is terminated with the characteristic impedance of the parallel wire.

  In the parallel wire according to the present invention, the far end is terminated with the characteristic impedance of the parallel wire, so that the matching between the impedance of the parallel wire and the characteristic impedance is obtained, the reflection at the end is minimized, and the phase change amount is accurately determined. Can be detected.

  Furthermore, the phase change amount according to the present invention is characterized by corresponding to the distance from the feeding end of the parallel wire where the capacitance is generated regardless of the capacitance generated between the parallel wires due to leakage.

  The phase change amount according to the present invention corresponds to the distance from the feeding end of the parallel wire where the capacitance is generated regardless of the capacitance generated between the parallel wires due to the leakage, and thus the parallel generation where the leakage occurs. The position on the electric wire can be pinpointed.

  Furthermore, the detection / determination means according to the present invention includes a phase change-distance conversion unit that converts the phase change amount from the phase change amount detection unit into a distance at which leakage occurs from the power supply end. .

  Since the detection / judgment means according to the present invention includes the phase change amount-distance conversion unit that converts the phase change amount from the phase change amount detection unit to the distance at which the liquid leakage occurs from the power supply end, the power supply of the leak sensor The position on the parallel electric wire where the liquid leakage has occurred from the end can be specified.

  The liquid leakage sensor device according to the present invention covers two parallel electric wires with an insulator, and forms a continuous groove or intermittent groove along the extending direction of the parallel electric wire at the center of the insulator, thereby forming the continuous groove or intermittent groove. A leakage sensor that generates capacitance between parallel wires due to leakage stored in the battery, and a high-frequency sine wave voltage applied to the power supply end of the leakage sensor, and parallel based on the capacitance generated in the leakage sensor Since the phase change amount of the high-frequency sine wave current flowing through the electric wire is detected, and the detection / determination means for determining the distance from the feeding end of the parallel electric wire corresponding to the detected phase change amount to the position where the leakage occurs, The leak sensor has a simple configuration in which the parallel wires are covered with an insulator, generates capacitance between the parallel wires due to the leak, and measures the phase change of the high-frequency sine wave current corresponding to the distance of the parallel wires. The detection / determination means generates a high-frequency sine wave current Since the phase change amount is detected and this phase change amount is determined as the distance from the feeding end of the parallel wire to the leak occurrence position, the leak position can be determined as a pinpoint on the parallel wire, With a leak sensor with a simple configuration, the leak position can be specified with high accuracy.

  In addition, since the parallel wire according to the present invention terminates at the characteristic impedance of the parallel wire, the matching between the impedance of the parallel wire and the characteristic impedance is obtained, the reflection at the end is minimized, and the phase change amount is accurately determined. It is possible to detect the liquid leakage position on the parallel wire corresponding to the phase change amount.

  Furthermore, the amount of phase change according to the present invention corresponds to the distance from the feeding end of the parallel wire where the capacitance is generated regardless of the capacitance generated between the parallel wires due to the leakage, so that leakage occurs. The position on the parallel electric wire can be pinpointed, and the liquid leakage sensor can be detected with high accuracy by making the liquid leakage sensor a simple configuration of the parallel electric wire.

  Further, the detection / judgment means according to the present invention detects the initial current flowing through the parallel wires in a reference voltage unit that supplies a high-frequency sine wave voltage to the feeding ends of the parallel wires and an initial state without leakage, and the sine A current detection unit for converting to a wave voltage, a cancel unit for adjusting and canceling the phase and amplitude of the sine wave voltage supplied from the reference voltage unit and the sine wave voltage supplied from the current detection unit, Phase change amount detection unit for detecting the phase change amount of the liquid current, phase-voltage conversion unit for integrating the phase change amount from the phase change amount detection unit and outputting it as a DC voltage, and a high frequency sine wave from the reference clock In addition to generating a voltage and a clock processing unit for generating a trigger pulse for detecting the amount of phase change, the phase of the initial current without leakage flowing through the parallel line is canceled, and output at a DC voltage of 0 v, The phase change amount of the hourly current is extracted by the pulse width, and this pulse width can be integrated to output a DC voltage corresponding to the phase change amount, and the occurrence of liquid leakage is recognized by the output of the DC voltage. The position of the liquid leakage on the parallel electric wires corresponding to the output of the DC voltage can be accurately specified.

  Further, the detection / judgment means according to the present invention includes the phase change amount-distance conversion unit that converts the phase change amount from the phase change amount detection unit into the distance at which the liquid leakage has occurred from the power supply end. The position on the parallel electric wire where the liquid leakage has occurred can be specified from the power feeding end of the battery, and the distance of the liquid leakage position where the liquid leakage has occurred can be recognized pinpoint.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in the present invention, in order to identify the position of leakage when leakage occurs from under the floor in a semiconductor factory or from a pipeline, a two-wire parallel wire covered with an insulator is placed under the floor or under the pipe. The phase change amount of the high-frequency sine wave current flowing in the parallel wires due to the capacitance generated between the parallel wires due to liquid leakage is detected, and the feed ends of the parallel wires corresponding to this phase change amount are detected. The distance from the liquid leakage position to the liquid leakage position is determined to identify the liquid leakage position.

  FIG. 1 is a basic configuration diagram of an embodiment of a liquid leakage sensor device according to the present invention. In FIG. 1, a liquid leakage sensor device 1 includes a liquid leakage sensor 2 and detection / determination means 3.

  The leak sensor 2 includes conductors C1. The two parallel wires EL of C2 are coated with an insulator Io, a high-frequency sine wave voltage Va is applied to the feeding end A1-A2 of the parallel wires EL, and the far ends B1-B2 of the parallel wires EL Is terminated with the characteristic impedance Zo of the parallel electric wire EL. By terminating the parallel wire EL with the characteristic impedance Zo, impedance matching can be achieved between the impedance of the parallel wire EL and the characteristic impedance Zo, and the reflection of the high-frequency sine wave voltage Va from the end is minimized. Can do.

  In addition, the leak sensor 2 is arranged in parallel along a pipeline for supplying wafer cleaning water in a semiconductor manufacturing factory, a pipeline for supplying cooling water for a nuclear power plant nuclear reactor, and the like. When water leaks, the leakage of cleaning water or cooling water is configured to wet the insulator Io or to be accumulated on the insulator Io.

  In addition, the leak sensor 2 shall be applied to the environment which is not exposed to rain water, dew condensation, etc., when there is no leak.

  In such a state, when a high-frequency sine wave voltage Va is applied to the power feeding end A1-A2 of the liquid leakage sensor 2, a high-frequency sine is applied to the parallel wires EL in an initial state where there is no leakage of cleaning water or cooling water. A wave initial current IN flows.

  This initial current IN includes conductors C1. The phase θ1 generated with the capacitance CN determined by C2 and the dielectric constant εN of the insulator Io appears.

  When leakage occurs at a position (leakage position P) at an arbitrary distance XS from the power feed end A1-A2 of the leakage sensor 2 from the initial state, a high-frequency sinusoidal leakage current IR flows through the parallel wire EL. .

  The leakage current I R includes the conductors C 1. By storing liquid leakage in C2 and the insulator Io, the capacitance Cm is generated as the dielectric constant of this portion (leakage position P) changes to the dielectric constant εR, and as the capacitance Cm is generated. The leaked phase θ2 appears. However, the leakage phase θ2 appears as the sum of the initial phase θ1 of the initial current IN and the phase change φ due to the capacitance Cm generated due to leakage.

  As will be described later, the phase change amount φ of the leakage current IR due to the occurrence of leakage is not related to the capacitance Cm when the capacitance Cm due to leakage is within a predetermined range. The distance XS from the power feeding end A1-A2 to the liquid leakage position P is determined.

  The detection / judgment means 3 applies a high-frequency sine wave voltage Va to the power feeding terminals A 1 -A 2 of the liquid leakage sensor 2, and the high-frequency sine flowing in the parallel electric wire EL based on the capacitance Cm generated in the liquid leakage sensor 2. The phase change amount φ of the wave current (leakage current IR) is detected, and the distance from the feed end A1-A2 of the parallel wire EL corresponding to the detected phase change φ to the leak occurrence position (leakage position P) (XS) is determined.

  FIG. 2 is a configuration diagram of an embodiment of a liquid leakage sensor according to the present invention. FIG. 2-a shows a cross-sectional view of the liquid leakage sensor, FIG. 2-b shows a liquid leakage sensor having a continuous groove, and FIG. 2-c shows a liquid leakage sensor having an intermittent groove. The liquid leakage sensor 2 includes conductors C1 and. Conductor C2 and conductors C1. And an insulator Io covering C2.

  The insulator Io is made of a material that does not dissolve in the liquid leakage, and forms a continuous groove M1 or an intermittent groove M2 in the center along the extending direction of the parallel electric wires EL, and the liquid leakage at a distance XS from the power feeding end A1-A2. When liquid leakage occurs at the position P, the target liquid leakage (for example, cleaning water or cooling water) is stored in the continuous groove M1 or the intermittent groove M2.

  In the initial state where there is no leakage, the leakage sensor 2 is connected to the conductors C1. A capacitance CN determined by C2 and the dielectric constant εN of the insulator Io is generated.

  On the other hand, when the leaked liquid is stored in the continuous groove M1 or the intermittent groove M2 of the insulator Io, the dielectric constant of the insulator Io including the leak changes to the dielectric constant εR in the vicinity of the leak position P, A capacitance Cm is generated.

  The electrostatic capacity Cm generated due to the leakage increases in the continuous groove M1 shown in FIG. 2B, since the leakage spreads around the leakage position P, and therefore increases according to the range in which the leakage is stored. become.

  On the other hand, in the intermittent groove M2 shown in FIG. 2C, since the leakage is stored in the intermittent groove M2 in the leakage position P, the capacitance Cm is determined by the size of the intermittent groove M2.

  The initial phase θ1 of the high-frequency sine wave initial current IN flowing through the leak sensor 2 appears in the initial state without leak due to the capacitance CN.

  On the other hand, when leakage occurs, the high-frequency sine wave leakage current IR flowing through the leakage sensor 2 has a leakage phase θ2 due to the capacitance CN and the capacitance Cm generated by storing the leakage. .

  By detecting the phase change amount φ, which is the deviation (= θ2-θ1) between the leakage phase θ2 of the leakage current IR and the initial phase θ1 of the initial current IN, the occurrence of leakage and the position P of the leakage are specified. can do.

  Next, the principle of determining the relationship between the capacitance Cm generated due to leakage, the phase change amount φ, and the distance XS from the power supply terminal A1-A2 to the leak position P from the phase change amount φ will be described. FIG. 3 is an experimental circuit diagram of an embodiment of the phase change amount according to the present invention. In FIG. 3, a high-frequency sine wave voltage Va is applied to the feeding end A1-A2 of the parallel wire EL, and the far end B1-B2 is terminated with the line impedance Zo of the parallel wire EL.

  A capacitance Cm (capacitor) is inserted at a distance XS from the power supply end A1-A2, a high-frequency sine wave current IL flowing through the parallel wire EL is measured, and a phase (phase change amount φ) of the sine wave current IL is measured. To detect. The capacitance Cm (capacitor) to be inserted is 10 pF, 30 PF, and 50 pF, and the distance XS from the power feeding end A1-A2 is 0 to 100 m.

  The phase change amount φ of the sine wave current IL when the electrostatic capacitance Cm is inserted between the parallel wires EL of the distance XS is generally expressed by the equation − (1), and ω = 2πf, β = ωZo, f Is the frequency of the sinusoidal voltage Va.

φ = tan ⁻¹ [1-ωCmZo-tan (β · XS)] / [2-ωCmZo tan (β · XS)] Equation (1).

  FIG. 4 is a calculation result diagram of an embodiment of the phase change amount according to the present invention. In FIG. 4, it is apparent that the phase change amount φ depends on the distance XS regardless of the value (10 to 50 pF) of the capacitance Cm shown in the equation (1). Note that the calculation result of the phase change amount φ coincides with the experimental result using FIG.

  Since the phase change amount φ of the leakage current IR due to the leakage depends on the distance XS from the power feeding end A1-A2, the position of the leakage occurrence position on the parallel wire EL is detected by detecting the phase change amount φ. The distance XS from the power supply end can be specified.

  Accordingly, the groove shape of the leak sensor 2 is such that the intermittent groove M2 shown in FIG. 2-c specifies the distance XS rather than the continuous groove M1 along the extending direction of the parallel electric wires EL shown in FIG. 2-b. desirable.

  Thus, since the parallel electric wire EL which concerns on this invention terminates far end B1-B2 with the line impedance Zo of the parallel electric wire EL, it can match between the impedance of a parallel electric wire, and characteristic impedance, and can reflect reflection of a termination | terminus. The phase change amount φ can be accurately detected with the minimum, and the liquid leakage position P on the parallel electric wire EL corresponding to the phase change amount φ can be specified.

  In addition, the phase change amount φ according to the present invention is equal to the distance XS from the power feeding end A1-A2 of the parallel wire EL where the capacitance is generated, regardless of the capacitance Cm generated between the parallel wires EL due to leakage. Therefore, it is possible to pinpoint the position (leakage position P) on the parallel electric wire where the liquid leak occurs, and make the leak sensor 2 a simple configuration of the parallel electric wire EL to increase the liquid leakage position. It can be detected with accuracy.

  Subsequently, the detection / determination means 3 for detecting the phase change amount φ of the leakage current IR flowing in the parallel electric wire EL and detecting the distance XS (leakage position P) from the power supply end at the time of leakage will be described. FIG. 5 is a block diagram showing the principal part of one embodiment of the detection / determination means according to the present invention. In FIG. 5, the detection / determination means 3 is connected to the power feeding ends A1-A2 of the parallel electric wires EL, and the reference voltage unit 4, the current detection unit 5, the cancellation unit 6, the phase change amount detection unit 7, and the phase-voltage conversion unit. 8. A phase-distance conversion unit 9 and a clock processing unit 10 are provided.

  The reference voltage unit 4 adjusts the amplitude of the high frequency sine wave voltage supplied from the band pass filter unit 13 of the clock processing unit 10, and, for example, applies a 1 v reference voltage (high frequency sine wave voltage Va) to the liquid leakage sensor 2. While being applied to the power feeding end A1-A2, it is provided to the cancel unit 6.

  The current detection unit 5 detects an initial current IN or a leakage current IR that is a high-frequency sine wave current flowing through the parallel electric wire EL of the leakage sensor 2, and the detected initial current IN or leakage current IR is detected as a high frequency. The signal is converted into a sine wave voltage signal, and the converted voltage signal is provided to the cancel unit 6.

  The cancel unit 6 compares the high-frequency sine wave voltage Va provided from the reference voltage unit 4 with the voltage signal obtained by converting the initial current IN provided from the current detection unit 5, and the phase, amplitude, and as necessary. Then, the polarity is reversed, the sine wave voltage Va and the voltage signal obtained by converting the initial current IN are canceled, and an output of 0 v is supplied to the phase change amount detection unit 7.

  The cancel unit 6 compares the voltage signal converted from the leakage current IR provided from the current detection unit 5 with the voltage signal obtained by correcting and outputting the voltage signal converted from the initial current IN at 0v. A voltage signal vK corresponding to the difference between the current IR and the initial current IN is supplied to the phase change amount detector 7.

  The voltage signal vK is an output corresponding to the difference current between the leakage current IR and the initial current IN because the voltage signal corresponding to the initial current IN is corrected (phase and amplitude) by the cancel unit 6. The phase of the voltage signal vK also becomes the phase change amount φ of the difference between the leakage current IR and the initial current IN.

  That is, the voltage signal vK has the phase change amount φ of the leakage current IR that flows when leakage occurs in the leakage sensor 2.

  The phase change amount detection unit 7 has a zero cross converter function and a flip / flop (F / F) function, and outputs a voltage signal vK, which is a high-frequency sine wave voltage supplied from the cancel unit 6, via the zero cross converter. By converting the pulse signal to a 50% pulse signal, using the pulse signal as an F / F set pulse, and using the trigger pulse supplied from the clock processing unit 10 as an F / F reset pulse, the phase change amount φ of the voltage signal vK Is detected as a phase detection output (pulse). The phase detection output (pulse) φ is provided to the phase-voltage conversion unit 8 and the phase-distance conversion unit 9. Note that the duty of the pulse signal may be greater than 50% (> 50%) or less (<50%).

  The phase-voltage conversion unit 8 includes an integration circuit and the like, integrates and averages the phase detection output (pulse) φ supplied from the phase change amount detection unit 7 and outputs the output voltage Vo.

  Since the output voltage Vo changes corresponding to the phase detection output (pulse) φ, the correspondence between the output voltage Vo and the phase change amount φ and the correspondence between the phase change amount φ and the distance XS from the power supply end shown in FIG. The distance XS (leakage position P) from the power feed end of the leak sensor 2 can be specified.

  The phase-distance conversion unit 9 stores a data table of the phase change amount φ and the distance XS from the power feeding end shown in FIG. 4, and based on the phase detection output (pulse) φ supplied from the phase change amount detection unit 7. The phase change amount φ is detected, the data table is searched, and the distance XS from the power feed end corresponding to the phase change amount φ is output. Thereby, the distance XS from the power feeding end to the liquid leakage position P can be specified.

  The clock processing unit 10 includes a crystal oscillation unit 11, a frequency division unit 12, a band pass filter unit 13, and a trigger pulse generation unit 14.

  The crystal oscillation unit 11 is configured by a crystal oscillator, generates a high frequency pulse of the crystal resonator, and supplies the high frequency pulse to the frequency division unit 12.

  The frequency dividing unit 12 is configured by a frequency dividing circuit, divides the high frequency pulse supplied from the crystal oscillation unit 11 into a predetermined number, and uses the divided frequency pulse as a reference pulse to generate the bandpass filter unit 13 and the trigger pulse. To the unit 14.

  The band-pass filter unit 13 filters the reference pulse supplied from the frequency dividing unit 12 to generate a high-frequency sine wave voltage of the reference pulse, and provides the generated high-frequency sine wave voltage to the reference voltage unit 4.

  The trigger pulse generator 14 generates a one-shot trigger pulse at the rising edge of the reference pulse supplied from the frequency divider 12, and provides the trigger pulse to the phase change amount detector 7.

  FIG. 6 is a waveform diagram of each part of the detection / determination means according to the present invention. In FIG. 6, the waveform (1) represents the reference pulse output from the frequency divider 12. The waveform of (2) represents the high frequency sine wave voltage Va supplied from the reference voltage unit 4 to the parallel electric wire EL.

  The waveform of (3) represents the leakage current IR detected by the current detector 5 and converted into the voltage signal vK. If the line impedance is capacitive, the phase is advanced, and if the line impedance is inductive, the phase is delayed. As in the embodiment, in the parallel two-wire electric line, the line impedance becomes capacitive and the phase advances. The waveform (4) represents a pulse signal obtained by the phase change amount detection unit 7 performing 0-cross conversion processing on the voltage signal vK and converting the voltage signal vK into a pulse having a duty of 50%.

  The waveform (5) represents a trigger pulse output from the trigger pulse generator 14. The waveform of (6) represents the phase detection output (pulse) φ output from the phase change amount detection unit 7. The waveform of (7) represents the output voltage Vo output from the phase-voltage conversion unit 8.

  FIG. 7 is a leakage position detection diagram of an embodiment of a leakage sensor device according to the present invention. In FIG. 7, the relationship between the distance XS from the power feeding end and the output voltage Vo using the capacitance Cm as a parameter (10 pF, 51 pF and 100 pF) is shown.

  As described above, the detection / determination means 3 according to the present invention includes the reference voltage unit 4 that supplies the high-frequency sine wave voltage Va to the power feeding ends A1-A2 of the parallel wires EL, and the parallel wires in the initial state without leakage. The current detection unit 5 that detects the initial current IN flowing through the EL and converts it into a sine wave voltage, and the phase and amplitude of the sine wave voltage supplied from the reference voltage unit 4 and the sine wave voltage supplied from the current detection unit 5 Cancellation unit 6 for adjusting and canceling, phase change amount detection unit 7 for detecting phase change amount φ of leakage current IR flowing at the time of leak, and phase change amount (phase detection output from phase change amount detection unit 7) Pal φ) is integrated and a phase-voltage converter 8 that outputs a DC voltage (output voltage Vo) and a clock that generates a high-frequency sine wave voltage from a reference clock and a trigger pulse that detects a phase change amount With the processing unit 10 As a result, the phase of the initial current IN without leakage flowing through the parallel wire EL is canceled and output with a DC voltage of 0 V, and the phase change amount φ of the leakage current IR is extracted with the pulse width (phase detection output pulse φ). The pulse width can be integrated to output a DC voltage (output voltage Vo) corresponding to the phase change amount φ, and the occurrence of liquid leakage is recognized by the output of the DC voltage (output voltage Vo). The liquid leakage position XS on the parallel wires corresponding to the output of the DC voltage (output voltage Vo) can be accurately specified.

  Further, the detection / judgment means 3 according to the present invention converts the phase change amount (phase detection output pulse φ) from the phase change amount detection unit 7 into the distance XS where the leakage has occurred from the power supply end A1-A2. Since the amount-distance conversion unit 9 is provided, the position (leakage position P) on the parallel electric wire EL where the liquid leakage has occurred from the power feeding end A1-A2 of the liquid leakage sensor 2 can be specified, and the liquid leakage occurs. The distance XS of the leaked liquid position P can be recognized pinpointed.

  As described above, the liquid leakage sensor device 1 according to the present invention covers the two parallel wires EL with the insulator Io, and the center of the insulator Io along the extending direction of the parallel wires EL or the continuous groove M1 or A leakage sensor 2 that forms an intermittent groove M2 and generates a capacitance Cm between the parallel electric wires EL due to leakage stored in the continuous groove M1 or the intermittent groove M2, and a power supply terminal A1-A2 of the leakage sensor 2 Applying a high-frequency sine wave voltage Va, detecting a phase change amount φ of a high-frequency sine wave current (leakage current IR) flowing in the parallel wire EL based on the capacitance Cm generated in the liquid leakage sensor 2; Since it is provided with detection / determination means 3 for determining the distance XS from the feeding end A1-A2 of the parallel wire EL corresponding to the detected phase change amount φ to the leakage occurrence position (leakage position P), the leakage sensor 2 is a simple configuration in which the parallel wire EL is covered with the insulator Io. A capacitance Cm between the parallel wires EL due to leakage is generated, and a phase change φ of the high frequency sine wave current corresponding to the distance XS of the parallel wires EL is generated. The phase change amount φ of the wave current (leakage current IR) is detected, and this phase change amount φ is determined as the distance XS from the feeding end A1-A2 of the parallel wire EL to the leak occurrence position (leakage position P). Therefore, the leak position can be determined as a pin point on the parallel wires, and the leak position can be specified with high accuracy by a leak sensor having a simple configuration of the parallel wires.

  In the present embodiment, the liquid to be leaked has been described as cleaning water or cooling water. However, the insulator of the leak sensor is not dissolved in the target liquid and the dielectric constant changes. Any liquid may be used.

  The liquid leakage sensor device according to the present invention applies a sinusoidal high-frequency voltage between two parallel wire lines, measures the phase of the initial current at which no liquid leakage occurs, Detects the phase of the leakage current flowing through the sensor and pinpoints the leakage position from the amount of phase change, which is the deviation between the phase of the leakage current and the phase of the initial current. The present invention can be applied to any liquid leakage sensor device that runs on electric wires.

Embodiment Basic Configuration of Leak Sensor Device According to the Invention Sectional view of a leak sensor according to the present invention Liquid leakage sensor configuration diagram having a continuous groove according to the present invention Configuration diagram of a leak sensor having an intermittent groove according to the present invention Experimental circuit diagram of one embodiment of phase change amount according to the present invention Calculation result diagram of one embodiment of phase change amount according to this invention Block diagram of main part of one embodiment of detection / determination means according to the present invention Waveform diagram of each part of detection / determination means according to the present invention One embodiment of a leak sensor apparatus according to the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Leak sensor 2 Leak sensor 3 Detection / determination means 4 Reference voltage part 5 Current detection part 6 Cancellation part 7 Phase change amount detection part 8 Phase-voltage conversion part 9 Phase-distance conversion part 10 Clock processing part 11 Crystal oscillation Part 12 Frequency Dividing Part 13 Band Pass Filter Part 14 Trigger Pulse Generating Part A1-A2 Feeding End B1-B2 Far End EL Parallel Wire C1. C2 Conductor Io Insulator Zo Line impedance P Leakage position Va High frequency sine wave voltage IN Initial current IR Leakage current L Parallel wire length L
XS Distance from feed end M1 Continuous groove M2 Intermittent groove Cm Capacitance θ1 Initial phase θ2 Phase at leakage φ Phase change

Claims (4)

By covering two parallel electric wires with an insulator, forming a continuous groove or an intermittent groove along the extending direction of the parallel electric wire at the center of the insulator, and leaking liquid stored in the groove or the groove-like groove A leakage sensor that generates a capacitance between the parallel wires, and a high-frequency sine wave voltage is applied to a power feeding end of the leakage sensor, and the parallel wires are applied to the parallel wires based on the capacitance generated in the leakage sensor. detecting a phase variation of the sinusoidal current of high frequency, a, a detecting / determining means for determining the distance from the feeding end of said parallel electric wire corresponding to the detected phase variation to leakage generation position configurations flowing Furthermore, the detection / determination means includes
A reference voltage unit for supplying a high-frequency sine wave voltage to the feeding end of the parallel wires;
A current detector that detects an initial current flowing through the parallel wires in an initial state without leakage and converts the current into a sine wave voltage;
A cancellation unit that adjusts and cancels the phase and amplitude of the sine wave voltage supplied from the reference voltage unit and the sine wave voltage supplied from the current detection unit;
A phase change amount detection unit for detecting a phase change amount of a leakage current that flows at the time of leakage;
Integrates the phase change amount from the phase change amount detection unit, outputs a DC voltage, and generates a high-frequency sine wave voltage from the reference clock, and generates a trigger pulse for detecting the phase change amount A clock processing unit to
A liquid leakage sensor device comprising:   The liquid leakage sensor device according to claim 1, wherein the parallel wire terminates a far end with a characteristic impedance of the parallel wire.   2. The phase change amount corresponds to a distance from the feeding end of the parallel wires in which the capacitance is generated regardless of the capacitance generated between the parallel wires due to liquid leakage. The liquid leakage sensor device described. The detection / determination means, wherein the phase change amount for converting the phase variation at a distance and liquid leakage from the feeding end is generated from the phase variation detecting unit - according to claim 1, characterized in that with a distance transform unit Liquid leakage sensor device.

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