JPH0725651Y2 - Leakage detector - Google Patents

Description

[Field of the Invention] The present invention relates to a leak detector, and more particularly to a multi-point leak detector that minimizes wiring between a monitoring device provided in a central monitoring room and a sensor provided at a plurality of monitored locations. Regarding vessels.

2. Description of the Related Art In the conventional device, as shown in FIG. 3, the central monitoring device (leakage warning panel) is composed of a multi-point detector having the same number of leak detection circuits as the leak sensors, and each of the sensors is connected to each other. There were devices that were connected by using multiple pairs of extension wires, and devices that had a resistance fault point detection type that measured and displayed the distance to the water leak point using a resistance measurement circuit using a special detection wire. When an additional water leak occurred, the additional sensor was connected to the central monitoring system with a new multi-pair extension line.

Problems to be Solved by the Present Invention Since the above-mentioned conventional device requires connection of a water leak detection circuit corresponding to each water leak sensor to the central monitoring device by each multi wire extension line, the multi wire extension line is connected. Will be used more. In addition, when adding a new location to be monitored, it was necessary to install a multi-pair extension line from the central monitoring device to the additional location.

Means for Solving Problems According to the typical solution of the present invention, at least one child device (C) for detecting water leakage having a parent device (M) forming a central monitoring device and a water leakage sensor is provided. And a common 2-wire signal transmission line (L) that connects each slave unit (C) to the master unit (M), and displays each slave unit identified by a number in a predetermined order, A leak detection device that displays an identification number and issues an alarm when water leakage is detected in any of the slave units, and counts clock pulses in synchronization with the master unit and each slave unit. And a control means 1 and 21 for synchronizing the counting start timing of each counter; the master unit has the following components: Precision clock generator 9 controlled by the control means Count output corresponding to the identification number of each slave unit when counting the clock pulses of Counter means 7 for sequentially generating
And a pulse detection circuit 3 for detecting a current pulse generated by a slave unit having water leakage detection means 37, 35 connected to each slave unit through the signal transmission line to detect water leakage, and an output of the circuit 3. And an alarm display circuit 11 for issuing an alarm together with the display of the identification number of the slave unit that has detected water leakage in response to the count output sequentially generated from the first counter means; Has the following components: water leakage detection means 37 for detecting water leakage at a measurement point and generating a water leakage detection output (Det); and a counting operation of the first counter means 7 controlled by the control means. The second counter means 27 for synchronously generating the count output, the code switch 33 for setting and outputting the voltage representing the identification number of the corresponding slave unit to which it belongs, the output voltage of the code switch and the second Compare with the counting output of the counter means A comparison circuit 31 for generating a coincidence display output (Acc) when both matches are obtained, and the water leakage detection output (Det) connected to the water leakage detection means 37, 35 and the comparison circuit 31. In response to the coincidence display output (Acc), the pulse current is connected to the signal transmission line (L) to transmit the leak information of the corresponding slave unit to the pulse detection circuit 3 of the master unit (M). And a current pulse circuit 29 for generating the water leak detection device.

The clock pulses 9 and 25 having the same contents are counted by the counters 7 and 27 in the parent device and the plurality of child devices, respectively. The counting operation of each counter is synchronized by providing a control means for synchronizing (making the same) the counting start time of each counter. At the time of starting the counting, the normal polarity output of the DC power supply 1 provided in the master unit is detected by the first counter means 7 or the polarity detection circuit 21 and set at the start of the same output (when the counter is reset). In each slave unit, a comparison circuit detects a match between the set voltage of the code switch 33 indicating the identification number of the slave unit and the count output of the second counter means 27, and a coincidence display output (Acc) generated and water leakage when water leakage is detected. In response to the water leak detection signal (Det) generated from the detection circuit 35, the current pulse circuit 29 of the corresponding slave unit generates a current pulse signal of a predetermined frequency, and the signal is a signal transmission line common to each slave unit ( L) is transmitted to the parent device. In the master unit, the first counter unit 7 which started the clock pulse counting at the same time as the second counter unit 27 of the slave unit generates the count output corresponding to the corresponding slave unit identification number in synchronization with the generation of the coincidence display output (Acc). The display circuit 11 issues a water leak warning of the corresponding slave unit by using the output of the transmitted current pulse signal detected by the pulse detection circuit 3 and the count output of the first counter means. Even after the comparison circuit 31 detects a match between the code switch 33 of the slave unit having the next identification number and the count output of the second counter means 27 of the slave unit, the same operation as described above occurs and Leakage inspection of multiple slaves is performed.

Embodiment FIG. 1 shows an embodiment of a water leak detection device according to the present invention, in which a main unit M constituting a monitoring device (water leak warning panel) provided in a central monitoring room and a two-wire transmission line L are connected to the main unit M. A block diagram of the slave C connected in parallel is shown. The master unit M includes an alarm / display circuit 11 having a DC power supply 1 for generating a DC output whose polarity is inverted at regular intervals, an alarm lamp 13, an alarm sound generator 15, a slave unit number display unit 17, a reset circuit 5, Black
Precision clock generator 9 for generating pulses,
A first counter 7, which counts the pulses and generates a voltage output corresponding to a slave unit number (a plurality of slave units are assumed to be connected), and outputs an alarm in response to a current pulse signal on the two-wire transmission line L. A pulse detection circuit 3 that generates a drive output for display is connected as shown in the figure. The cordless handset C is a code for generating a corresponding output voltage by setting a water leak sensor 37 indicating a resistance drop when in a flooded state, a water leak detection circuit 35 generating an output signal Det indicating the resistance drop, and an identification number of the corresponding handset. The switch 33, a second counter 27 that counts clock pulses from the precision clock generator 25 having the same configuration as the precision clock generator 9 of the master unit, and generates a voltage output corresponding to the corresponding slave unit identification number. Comparison circuit 3 for comparing with the code switch output and generating the coincidence display output signal Acc
1, a polarity detection circuit 21, which is connected to the master DC power supply 1 via the rectifier 23 and the transmission line L, and outputs a reset signal to the counter 27 when the DC power supply reverses its polarity from normal polarity, water leakage detection output Det and coincidence A current pulse circuit 29 for receiving the display output signal Acc and outputting a current pulse of a predetermined frequency on the transmission line L is connected as shown in the figure.

In the above structure, the water leakage sensor 37 and the water leakage detection circuit 35 constitute the water leakage detection means referred to in the present invention.
The counter 27 constitutes counter means, and the DC power source 1 and the polarity detection circuit 21 constitute control means for synchronizing the counter means.

A description will be given of a water leak detecting operation in the case where a plurality of slave units 1 to n are connected in parallel to the transmission line L and the slave unit C shown corresponds to the i-th unit in the water leak detecting device having the above-described configuration. Base unit M
On the side, when the detection operation starts, the reset of the counter 7 is released by the output change from the inversion polarity of the DC power supply output to the normal polarity. During the normal polarity period of the power output,
The counter 7 counts the clock pulses from the precision clock generator 9 and sequentially applies the output code voltages corresponding to the slave unit numbers 1 to n to the alarm display circuit 11 for every predetermined number. 1-n
The leakage detection state of the slave unit is examined in order via the transmission line L in synchronization with the count value of the counter 7, and if there is leakage, the alarm display circuit 11 is driven via the current pulse circuit 29 and the pulse detection circuit 3. Then, the alarm and the count value of the counter 7 at that time, that is, the slave unit number which has detected the water leakage are displayed. For example, in the i-th cordless handset C, when the water leak detection sensor 37 detects water leak, the indicator 17 displays the number i and the alarm lamp
13 and the alarm sound generator 15 generate an alarm.

On the i-th handset C side, an output code voltage Vi indicating that the code switch 33 is the i-th handset is preset and applied to one input terminal of the comparison circuit 31. When the water leak detection sensor 37 is flooded, the water leak detection circuit 35 applies the signal Det to one input terminal of the current pulse circuit 29. On the other hand, the polarity detection circuit 21 starts the counting operation of the counter 27 in response to the output change of the DC power supply 1 applied via the transmission line L and the full-wave rectifier 23 from the above-mentioned inverted polarity to the normal polarity. Counter during this normal polarity period
Reference numeral 27 counts the clock pulses from the precision clock pulse generator 25 and applies the output code voltage corresponding to the slave unit numbers 1 to n to the other input terminal of the comparison circuit 31 for every predetermined number. The generation of the code voltages corresponding to the child device numbers 1 to n of the counters 7 and 27 is set so that they are temporally at the same time. The comparison circuit 31 detects a match between the counter output code voltage and the output code voltage Vi of the code switch 33 and applies a match output signal Acc to the current pulse circuit 29. Current pulse circuit 29 is a signal
With the inputs Acc and Det, a current pulse of a predetermined frequency is generated and output on the transmission line L. In response to the current pulse, the pulse detection circuit 3 of the master unit drives the alarm lamp 13 and the alarm sound generator 15 of the alarm / display circuit 11. While the comparator circuit 31 is outputting the signal Acc, the alarm display circuit 11 of the master unit also displays the slave unit number i, so it is displayed that the sensor of the slave unit has detected water leakage.

The reset circuit 5 of the master unit is connected to the DC power source 1 and forcibly returns the output of the DC power source to the starting end of the normal polarity output at an arbitrary time point to start the detecting operation from the slave unit 1. Both the parent device and the child device are assumed to use the power of the DC power supply 1 as the circuit operating power, but the child device may have its own power source. Instead of the slave unit current pulse circuit 29, an oscillator circuit that receives the signals Acc and Det and outputs a pulse signal of a predetermined frequency may be used to superimpose the pulse signal on the DC power on the transmission line L.

FIG. 2 shows a configuration in which the parent device M and a plurality of child devices 1 to n are connected, and an additional water leakage sensor Sa and an additional child device Ca are connected to cope with the occurrence of a new leakage point. In the conventional configuration shown in FIG. 3, the additional water leakage sensor Sa is provided with a separate additional extension line to be connected to the water leakage warning panel, but according to the present invention shown in FIG. Only the extension transmission line that connects the additional slave Ca can be used. Therefore, the amount of transmission lines used can be reduced.

Although the water leak sensor is displayed in the child device block in FIG. 1, the child device main body and the sensor do not necessarily have to be provided in the same place, and as shown in FIG. The sensor may be separated and connected. Various other design changes are possible. In addition, although the embodiment shows the water leak detector, the sensor detects a change in the state of the measured point and issues an alarm.
It is obvious that the present invention can be applied to various alarm devices to be displayed, and the present invention is not limited to the illustrated configuration.

Effect The amount of signal transmission lines connecting the sensor and the central monitoring equipment can be saved to a minimum. You can easily add or move sensors.

[Brief description of drawings]

FIG. 1 is a block wiring diagram showing an embodiment of a one-way transmission type leak detection device according to the present invention, and FIG. 2 is a connection diagram when a plurality of slave units of the device of FIG. 1 are arranged, and FIG. The figure is a connection diagram of a conventional example. M: base unit, 1 ... DC power supply, 3 ... pulse detection circuit,
5 ... Reset circuit, 7 ... Counter, 9 ... Precision clock generator, 11 ... Alarm / display circuit, 13 ... Alarm lamp, 15 ... Alarm sound generator, 17 ... Slave unit number display, C ...
… Slave unit, 21 …… Polarity detection circuit, 23 …… Full wave rectifier, 25…
… Precision clock generator, 27 …… Counter, 29 …… Current pulse circuit, 31 …… Comparison circuit, 33 …… Code switch, 35
... Leakage detection circuit, S ... Leakage detection sensor, L ... Signal transmission line.

Claims (2)

[Scope of utility model registration request] 1. A master unit (M) forming a central monitoring device and at least one slave unit (C) for detecting a leak having a leak sensor, and each slave unit (C) in the master unit (M). And a common two-wire signal transmission line (L) for connecting each of the cordless handsets, each cordless handset identified by a number is displayed in a predetermined order, and if any one of the cordless handsets has detected water leakage, the corresponding identification number is displayed. Is a water leakage detection device that issues an alarm together with the display of, and has counter means for counting clock pulses in synchronization with the master unit and each slave unit, and the counting start timing of each counter The master unit has the following components: Each of the master units is controlled by the control unit to start counting clock pulses of the precision clock generator (9). First counter means (sequentially generating a count output corresponding to the identification number of the slave unit) ), And a pulse detection circuit (3) for detecting a current pulse generated by a slave unit having water leakage detection means (37, 35) connected to each slave unit through the signal transmission line to detect water leakage. An alarm display circuit (11) for issuing an alarm together with an identification number of the slave unit that has detected water leakage in response to the output of the circuit (3) and the count output sequentially generated from the first counter means. In addition, each slave unit has the following components: Water leakage detection means (37, 35) for detecting water leakage at a measurement point and generating a water leakage detection output (Det), and control by the control means Second counter means (27) for generating a count output in synchronization with the counting operation of the first counter means (7)
And a code switch (33) for setting and outputting a voltage representing the identification number of the corresponding slave unit to which it belongs, and the output voltage of the code switch and the count output of the second counter means are compared. When a match is obtained, a comparator circuit (31) for generating a match display output (Acc), the water leak detection means (37, 35) and the comparator circuit (31) are connected to detect the water leak. Output (Det) and the match display output (Acc)
And a current pulse circuit connected to the signal transmission line (L) to transmit the leak information of the corresponding slave unit to the pulse detection circuit (3) of the master unit (M) in response to (29) The water leakage detection device having: 2. The DC power supply (1), wherein the control means (1, 21) includes a DC power supply (1) provided in the master unit and a polarity detection circuit (21) provided in each slave unit. Has a function of alternately inverting the output polarity between the normal polarity output and the inverted polarity output, and when the DC power source (1) in the master unit is inverted from the normal polarity output to the inverted polarity output, first counter means (7) ) Is reset and then returns from the inverted polarity output to the normal polarity output, the first counter means starts counting the precision clock (9), while each slave unit passes through the signal transmission line (L). Are connected to the DC power supply (1), the respective polarity detection circuits (21) output normal polarity output in response to the change in the output polarity of the DC power supply (1). The second counter means (27) resets When the reverse polarity output is returned to the normal polarity output after that, the counting of the precision clock (25) is started by the second counter means (27) to count the first counter means and the second counter means. The leak detection device according to claim 1, characterized in that the start is synchronized.