JPH0668368A - Gas leak warning cutoff system - Google Patents

Abstract

PURPOSE:To wire and connect plural gas leak alarm units to one gas meter, to accurately transmit an answer signal from the gas meter to all the gas leak alarm units and make a warning, and to reduce the battery consumption for the transmission. CONSTITUTION:The gas leak alarm units 2 and one gas meter 1 are wired and connected through a repeating adapter 10. Alarm signals from the gas leak alarm units are monitored by the monitor part 10b of the repeating adapter and when the alarm signal is inputted from even one alarm unit to the alarm- side input/output part 10a of the repeating adapter, the alarm signal from the gas leak alarm unit is outputted to the gas meter through the meter-side input/ output part 10c of the repeating adapter while inhibited from being outputted to the gas leak alarm unit. Further, when an answer signal is inputted from the gas meter through the meter-side input/output part, the input of the alarm signal is inhibited for a time of one answer signal and the answer signal from the gas meter is outputted to all the gas leak alarm units through the alarm-side input/output part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas leak alarm device which has a non-voltage output terminal and outputs an alarm signal at a constant cycle during an alarm, and a gas meter which incorporates a shutoff valve and outputs an answer signal such as a closing signal thereof. The present invention relates to a gas leak alarm cutoff system for connecting and wiring.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a conventional gas leak alarm shutoff system of this type. In the figure, the solid line indicates the wiring connection state of one gas meter 1 and one gas leak alarm device 2, and the dotted line indicates the state in which a plurality of gas leak alarm devices 2 are additionally connected. The gas leak alarm device 2 transmits / receives a signal to / from the gas meter 1 through two wires 5 that connect the pair of non-voltage output terminals 3 and the pair of input / output terminals 4 on the gas meter 1 side.

The gas leak alarm device 2 includes a gas leak detection unit 6 for detecting a gas leak, an alarm unit 7 for notifying a gas leak according to the detection, and an external output unit 8 composed of two photocouplers PC1 and PC2. When a gas leak is detected, the photocoupler PC1 is repeatedly turned on and off at regular intervals, and an alarm signal is transmitted to the gas meter 1 at regular intervals through the wiring 5. When the gas meter 1 continues to detect the alarm signal for a certain period of time, it shuts off the built-in shutoff valve and returns an answer signal indicating the closing of the shutoff valve to the gas leak alarm device 2 through the wiring 5.

In the gas leak alarm device 2, when no gas leak is detected, the photocoupler PC1 is kept in the ON state. When the answer signal from the gas meter 1 is received, the photocoupler PC2 is turned on / off to change the potential at the point A. Then, the change in the potential at the point A is discriminated, and the alarm signal of the shutoff valve closing, advance notice, use permission, and 1-minute monitoring answer signal is given by the alarm unit 7.

FIG. 8 shows a timing chart of an operation example of the photocouplers PC1 and PC2, and FIG. 9 shows an example of an answer signal for shutting off the shutoff valve, notifying, permitting use, and 1 minute monitoring.

[0006]

Conventionally, the connection between a gas leak alarm having a non-voltage output terminal and a gas meter having a shut-off valve is, as shown by the solid line in FIG. 7, one for each. It is normal to connect each gas meter one by one, and a system in which multiple gas leak alarms are connected to one gas meter has not been put to practical use, and as shown by the dotted line, multiple gas leak alarms are provided for each gas meter 1. Although it is conceivable to wire the container 2 so-called crossover wiring, it has not been put into practical use because of the following problems.

That is, if additional crossover wiring as shown by the dotted line is performed, even if one of the plurality of gas leak alarms 2 detects a gas leak and the photocoupler PC1 repeatedly turns on and off, If other gas leak alarms are in the monitoring state, those photocouplers PC1 are turned on, so that the two wirings 5 are in a conductive state and the gas leak alarm signal cannot be discriminated on the gas meter 1 side. Further, with respect to the gas leak alarm device in which the photocoupler PC1 is turned off in the monitoring state and repeatedly turned on and off at the time of alarm, the gas leak alarm signal can be discriminated by the gas meter.

However, since a plurality of diodes of the photocoupler PC2 are connected in both of these gas leak alarms, the current consumed by the diodes increases when the answer signal is output from the gas meter, and the gas meter is equipped with this. Expends the consumed battery. If the voltage across the diode of the photocoupler PC2 varies, A
The potential of the point also varies, and it becomes impossible to accurately determine and notify the answer signal.

The object of the present invention is to solve the above problems,
It is possible to connect multiple gas leak alarms with non-voltage output terminals to one gas meter with a built-in shutoff valve without any problem, and the answer signal from the gas meter can be accurately applied to all gas leak alarms. Another object of the present invention is to provide a highly reliable gas leak alarm cutoff system that can transmit and notify the user of the gas leak and reduce the battery consumption required for the transmission.

[0010]

In the gas leak alarm shutoff system according to the present invention, a relay that enables connection of a plurality of gas leak alarms to one gas meter and relays signal transmission between them. Equipped with an adapter. The relay adapter is capable of inputting / outputting a signal to / from a plurality of gas leak alarms, and has an alarm side input / output unit capable of switching its input and output and one gas meter. Monitors the meter-side input / output section that inputs and outputs signals between them and the signal input from the alarm-side input / output section and meter-side input / output section, and issues an alarm from any one of a plurality of gas leak alarms. When an alarm signal is input to the side input / output section,
The output from the alarm device side input / output unit to the gas leak alarm device is prohibited, and the alarm signal from the gas leak alarm device is output to the gas meter through the meter side input / output unit, and the gas meter outputs the answer through the meter side input / output unit. When a signal is input, it has a monitoring unit that prohibits the input of the alarm signal in the alarm side input / output unit and outputs the answer signal from the gas meter to all gas leak alarms through the alarm unit side input / output unit.

[0011]

The alarm signals from a plurality of gas leak alarms are monitored by the monitoring section of the relay adapter, and if any one of the alarm signals is input to the alarm side input / output section of the relay adapter, the alarm signals are output. While the output from the side input / output unit to the gas leak alarm is prohibited, the alarm signal from the gas leak alarm is output to the gas meter through the meter side input / output unit of the relay adapter. When an answer signal is input from the gas meter through the meter-side input / output unit, conversely, the alarm signal input is prohibited at the alarm-side input / output unit for one answer signal time, and the answer signal from the gas meter is input. Is output to all gas leak alarms through the input / output unit on the alarm side.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of the configuration of a gas leak alarm cutoff system according to the present invention. This gas leak alarm cutoff system includes a relay adapter 10, and a plurality of gas leak alarms 2 are connected to one gas meter 1 by wiring via the relay adapter 10. The gas leak alarm 2 itself is the same as the conventional example shown in FIG. 7, and there is no change. The same applies to the gas meter 1. The relay adapter 10 includes an alarm device side input / output unit 10a, a monitoring unit 10b, and a meter side input / output unit 10c.
Is roughly divided into

The alarm device side input / output section 10a includes a pair of non-voltage output terminals 3 and two wirings 11 of n gas leak alarm devices 2.
And n pairs of input / output terminals I _{1 to} In respectively connected to each other, and n first and second
Third and fourth analog switch _{A 1 ~An · B 1 ~Bn ·} a
_{1 to} an.b _{1 to} bn and n resistors R _{1 to} Rn for discriminating the gas leak alarm 2.

The monitoring unit 10b is an alarm unit side input / output unit 10a.
A first logic circuit C for logically processing a gas leak alarm signal input to the microcomputer D, a microcomputer D for monitoring its output, and a second logic circuit E for canceling an answer signal from the gas meter 1 when a gas leak is detected. It consists of and.

The meter side input / output section 10c is a gas meter 1
Pair of input / output terminals 4 connected to the pair of input / output terminals 4 by two wires 12 and two photocouplers PC3
-It consists of PC4.

FIG. 2 shows the input / output truth value relationship of the first logic circuit C, and FIG. 3 shows the input / output truth value relationship of the second logic circuit E. Further, FIG. 4 shows a microcomputer D.
3 shows a flowchart of the operation processed by the. The operation will be described below according to this flowchart.

First, in step S1, the microcomputer D is set to the initial state, its internal counter CN is set to 0, the P ₁ port of the microcomputer D is set to L, Px.
The port and Py port are detected, and the P ₂ port is set to L.

Next, in step S2, the P ₁ port is set to H. At this time, the first and second analog switches A _{1 to} An
When B _{1 to} Bn are turned on and all of the gas leak alarms 2 connected to the input / output terminals I _{1 to} In are in the monitoring state, current flows through the resistors R _{1 to} Rn and a voltage is induced at both ends thereof. . Therefore, as shown in FIG. 2, the inputs of the logic circuit C are all H, the outputs thereof are L, and the Px port of the microcomputer D is L. Therefore, it is determined in step S3 that Px = L,
Go to step S4. Since CN (internal counter) = 0 in step S4, the process proceeds to step S5. When the Py port is L in step S5, the process returns to step S2 and the above operation is repeated to continue the monitoring operation.

When the Py port is H in step S5, that is, when the second photocoupler PC4 of the meter side input / output section 10c is turned on by the answer signal from the gas meter 1, the process proceeds to step S6. ₁ port is L
And at the same time, the first and second analog switches A _{1 to} An
· B ₁ to Bn off the third with H output from the logic circuit E
・ Turning on the fourth analog switches a _{1 to} an and b _{1 to} bn, that is, operating the photocoupler PC2 of the all gas leak alarm device 2 in synchronization with the answer signal of the gas meter 1, and issuing a notification according to the answer signal. Let In step S7, the timer is operated in order to transmit the answer signal to the gas leak alarm 2 for one time.

When even one of the n gas leak alarms 2 detects a gas leak during the gas leak monitoring as described above, the photocoupler PC1 in the gas leak alarm 2 causes the photocoupler PC1 to operate as shown in the timing chart of FIG. Repeat on and off.
At this time, when the voltage across one or more of the resistors R _{1 to} Rn becomes ground level due to the photocoupler PC1 being turned off in step S2, the output of the first logic circuit C becomes H, and the Px port becomes H in step S3. Therefore, the process proceeds to step S8. The P ₁ port is H.

In step S8, the P ₂ port is set to H, the first photocoupler PC3 of the meter side input / output unit 10c is turned off, and the process proceeds to step S9. In step S9, a timer for the off time is operated to allow a certain time to elapse, and the process proceeds to step S10. Step of P ₂ port from the turn on the photocoupler PC3 in the L at step S10 S11
Go to. In step S11, a timer for the ON time is operated to allow a certain time to elapse, and the process proceeds to step S12 to set the internal counter to 1. Next, returning to step S2, when the Px port is H in step S3, the same operation is repeated. As a result, the photocoupler PC3 is repeatedly turned on and off, and the gas leak alarm signal is transmitted to the gas meter 1.

When it is determined in step S3 that the Px port is L and the internal counter CN is determined to be 1 in step S4, the process proceeds to step S13. In steps S13 to S18, the Px port becomes H only within a short fixed time after step S4 in order to eliminate a malfunction due to the difference between the on / off time of the gas leak alarm device 2 and the on / off time of the microcomputer D. Closely monitor whether or not. When the Px port becomes H within this time, the process proceeds from step S16 to step S8, and the alarm operation is repeated. On the right side of FIG. 5, at the time of step S3 and step S1.
The difference between the H and L inversion operations in the case of 6 is shown.

In step S13, the memory M in the microcomputer D is set to 0, and in step S14, a timer shorter than the on / off time is operated. In step S15, 1 is added to the memory, and in step S16, it is determined whether or not the Px port is H. If it is H, the process proceeds to step S8, and if it is L, the process proceeds to step S17 to determine whether or not the memory has reached the set value XX. When the set value is reached, the process proceeds to step S18, the internal counter CN is set to 0, the process proceeds to step S5, and the monitoring state is continued as described above. The above operation is the same as shown in FIG. 6 when a plurality of gas leak alarms 2 issue a gas leak alarm.

[0024]

According to the gas leak alarm cutoff system according to the present invention, a plurality of gas leak alarms each having a non-voltage output terminal, and a single gas leak alarm device which incorporates a cutoff valve and outputs an answer signal such as a closing signal thereof. If the alarm signal is input to the relay adapter from any one of the gas leak alarms by wiring connection to the gas meter via the relay adapter, the output from the gas meter side to the gas leak alarm is prohibited in the relay adapter. On the other hand, when the alarm signal from the gas leak alarm is output to the gas meter through the relay adapter, and when the answer signal is input from the gas meter to the relay adapter, the answer signal from the gas meter leaks all gas through the relay adapter. Output to alarm device. Therefore, the answer signal from the gas meter can be accurately transmitted to all the gas leak alarms to be notified, and the battery leak alarm cutoff system with high reliability can reduce the battery consumption required for the transmission.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an example of a gas leak alarm cutoff system according to the present invention.

FIG. 2 is a diagram showing a truth value relationship between inputs and outputs of a first logic circuit of the relay adapter of the same system.

FIG. 3 is a diagram showing a truth relation of inputs and outputs of a second logic circuit of the relay adapter of the same system.

FIG. 4 is a flowchart illustrating an operation of the system.

FIG. 5 is a timing chart when one gas leak alarm device issues an alarm in the system.

FIG. 6 is a timing chart when two gas leak alarms issue an alarm.

FIG. 7 is a configuration diagram of a conventional gas leak alarm cutoff system.

FIG. 8 is a timing chart of the above.

FIG. 9 is an aspect diagram of various answer signals from the gas meter in the above.

[Explanation of symbols]

 1 gas meter 2 gas leak alarm device 3 non-voltage output terminal 10 relay adapter 10a alarm device side input / output unit 10b monitoring unit 10c meter side input / output unit

Claims (1)

[Claims] A gas leak alarm device having a non-voltage output terminal for outputting an alarm signal at a constant cycle at the time of alarm, and a gas meter for wiring connecting a gas meter having a shut-off valve and outputting an answer signal such as a closing signal thereof. In the leak alarm cutoff system,
A relay adapter that relays one gas meter and a plurality of the gas leak alarms is provided, and the relay adapter can input and output a signal to and from the plurality of gas leak alarms, An alarm side input / output unit that can switch between input and output, a meter side input / output unit that inputs and outputs signals to and from one gas meter, and these alarm side input / output unit and meter side input / output unit Monitoring the signal input from the gas leak alarm device, and if any one of the gas leak alarm devices has an alarm signal input to the alarm input / output unit, the gas leak from the alarm device input / output unit is detected. When output to the alarm device is prohibited and an alarm signal from the gas leak alarm device is output to the gas meter through the meter-side input / output unit, and an answer signal is input from the gas meter through the meter-side input / output unit. Is a policeman And having a monitoring unit for outputting an answer signal from the gas meter in the side output section to total gas leak alarm through the alarm device-side input-output unit, gas leak alarm shut-off system.