JPS60157697A - Gas cut-off valve controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a shutoff system in which a gas leakage signal generated when a gas leakage detector detects a gas leakage is input, and a gas shutoff valve provided in a gas flow path is closed in response to the gas leakage signal. This invention relates to a gas cutoff valve control device that generates a signal.

This type of device, together with a gas leak detector and a gas shutoff valve, constitutes a gas leak detector interlocking shutoff system. Conventionally, as shown in FIG. 1, in such a system, a gas leak detection alarm 1 and a shutoff valve 2 are electrically connected via a controller 3, and the alarm 1 detects leaked gas. There is a known device that automatically closes the gas flow path and stops the gas supply if the alarm continues to be issued for a certain period of time or more, thereby preventing further gas leakage.

The controller 3 closes the cutoff valve 2 in response to gas leak detection by the alarm 1, thereby preventing further gas leaks and ensuring safety.

However, the conventional controller 3 only generates a single shutoff signal after a predetermined period of time in response to the occurrence of a gas leak signal. Therefore, if the valve body of the shutoff valve 2 is mechanically stuck and cannot be switched by the single shutoff signal described above, there will be no chance to close the shutoff valve 2 after that, causing a dangerous situation due to continued gas leakage. This caused an extremely serious safety problem.

By the way, some conventional gas cutoff valves have a switch that opens and closes in conjunction with the opening and closing of the valve, and a valve closing signal is input to a controller via a signal line depending on the state of the switch. . However, in the past, this valve close signal was used merely as a signal to indicate valve shutoff in the controller.

The present invention has been made in order to solve the problems of the conventional ones described above, and its purpose is to proactively utilize valve signals corresponding to the open/closed state of the valve generated by the gas cutoff valve, and to To provide a gas shutoff valve control device that securely closes the shutoff valve and further improves safety by repeatedly generating a shutoff signal until a leakage signal input release valve close signal is input. .

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a schematic configuration of a gas leak detector interlocking shutoff system using the gas shutoff valve control device according to the present invention. The illustrated system includes three gas leak detectors 10 and a gas cutoff valve 20a of a gas meter section 20.

It is composed of a control device 30 and the like according to the present invention.

When gas leaks, the gas leak detector 10 detects the gas at one-quarter or less of the lower explosive limit, displays a lamp, and outputs a gas leak signal to the control device 30. In addition, intentional damage to a part of the sensor of the gas leak detector 10 (self-inflicted acts such as suicide)
Detects any act of self-inflicted injury, etc., and outputs a self-inflicted act signal to the control device 30.

The control device 30 receives a gas leak signal and a self-inflicted act signal from the gas leak detector 10, issues an alarm with a buzzer and a lamp in response to the gas leak signal, and outputs a cutoff signal to the gas cutoff valve 20a. Further, the gas cutoff valve 20a can be manually shut off using the manual cutoff switch 309 on the control device 30.

Furthermore, it is also possible to output an external output signal that can be linked to an external device O such as a central monitoring panel in an apartment complex or the like. Shutoff valve 20
a receives a cutoff signal from the control device 30, closes the valve 20a, and outputs a valve close signal for displaying the cutoff valve on the control device 30.

In order to do both of these things, the control device 30 has a number of terminals on its back side as shown in FIG.

First, there are nine 24V terminals 30a and three O terminals 30b that supply power to the three gas leak detectors 10, and three signal terminals 30C that accept input signals from the three gas leak detectors 10. The terminals are arranged in one row. In addition, three terminals 30d, 30e, 30f are connected to the gas cutoff valve 20a to connect 3-core cables for Φ, ○ and signals, and two terminals for Φ and θ are connected to the auxiliary contacts of the breaker. Seven terminals, terminals 30g and 30h, and two terminals 30i and 30j for Φ and θ, which output signals according to input signals from the gas leak detector 10 to the external device 40, are located at a certain distance from the terminals 30a to 30c. l1i
lt11! and arranged in a line. Furthermore, there is a power terminal 30 at the bottom for drawing AC 100V power into the device.
k is provided.

On the surface of the control device 30, as shown in FIG. 2, there is a power lamp 307 composed of a light emitting diode! In addition to the alarm lamp 30m and the cutoff lamp 30n, there is also a switch that can be set to either the monitoring side to shut off the gas shutoff valve in the event of a normal gas leak or self-damage, or to the manual side to shut off the shutoff valve immediately. A manual switch 30T) configured by a waveform switch to select is provided, and a control circuit for controlling the above-mentioned operations is housed inside the manual switch 30T.

By the way, each of the gas leak detectors 10 operates by being supplied with a DC 24V voltage from the terminals 30a and 30b of the control device 30, and when a gas leak is not detected, the voltage is 6V, and when a gas leak is detected, the voltage is 12V (gas leak signal), When a disconnection of the connection line between the gas sensor section and the Meborya control device 30 is detected, a voltage signal that becomes an OV (self-inflicted act signal) is generated and applied to the corresponding one of the terminals 30C.

Further, the gas cutoff valve 20a, as shown in FIG.
It has a valve operating circuit 21, a valve interlocking magnet 23, and a reed switch 24 that is turned on and off by the magnet 23, and is turned on when the valve is opened and turned off when the valve is closed. The valve actuation circuit 21 includes terminals 30d' and 30e' connected to terminals 30d and 30e of the control device 30 via connection lines.
and a 20V discrimination circuit 21a that determines when the voltage between the terminals 30d' and 30e', which is normally about 6■, reaches about 20V, and when the voltage between the terminals 30d' and 30a' is OV.
It consists of a 0V discrimination circuit 21b that discriminates when the voltage is 0V, and a valve opening/closing circuit 21c. The circuit 21C is the circuit 20 described above.
A switch element SWI is triggered by the 20V voltage discrimination by the V discrimination circuit 21a, and a switch element S is triggered by the OV lightning voltage discrimination by the Ov discrimination circuit 21b.
When SWI becomes conductive, a thick current is passed through the valve drive coil in the direction of the solid arrow to open the valve, and SW2
The electrical charge in the capacitor C is discharged by the conduction of the capacitor C, and a small current is passed through the valve drive coil in the direction of the dotted arrow to close the valve.

It should be noted that the 20V OV lightning voltage applied from the control device 30 between the terminals 30d' and 30a' provides the necessary force to establish the closed state and open state of the cutoff valve 20a, and provides a predetermined signal as a cutoff signal and a valve return signal, respectively. It is applied only for a short time, and at other times 6 is applied between terminals 30d' and 30a'.
A voltage of (2) is applied.

Next, the configuration of the control device 30 will be explained with reference to FIG. 5, in which the same parts as those in FIGS. 2 to 4 are given the same reference numerals.

In the figure, 31 is a detector power supply circuit, which steps down AClooV supplied to the terminal 30k via a breaker (not shown) by a transformer T, rectifies and smoothes the applied AC to obtain DC 24V, and supplies this to the terminal 30a. , 30b to three detectors 10. A short circuit protection circuit 32 protects the power supply circuit 31 from being damaged due to a short circuit between the terminals 30a and 30b.

33 is a power supply circuit that supplies DC power to the control circuit of the device, and the DC obtained by rectifying and smoothing the voltage of the AClooV supplied to the terminal 30k by the transformer T and rectifying and smoothing the supplied AC is indicated by the black arrow. It is supplied from this section to each section in the circuit indicated by the same arrow. This rectified and smoothed DC is made into a constant voltage and is supplied from the part indicated by the white arrow to each part in the circuit indicated by the same arrow.

34 is a buck-up power supply circuit, which has a large-capacity charging capacitor C1 that is charged via a diode D by the rectified and smoothed DC.

The hack-up voltage stored in this capacitor C1 is approximately 6 mm, and is supplied from the part indicated by the single point arrow to each part in the circuit indicated by the same arrow, but the part to which this voltage is supplied is
Manual switch 30p after looV supply runs out
This circuit is necessary for shutting off the valve when the breaker is shut off, or shutting off the valve 5 minutes after the breaker is shut off. Note that the same diode D as above is used to prevent backflow.

35 is a shutoff valve output circuit, in which a switching transistor circuit Q+ connected between the backup power supply 34 and the terminal 30d is turned on and off by a signal applied to its base, and when on, approximately 6V is applied between the terminals 30d and 308.
When the terminal is off, the voltage between the terminals 30d and 30a is set to OV. This 0■ voltage becomes a cutoff signal that closes the cutoff valve 20a.

36 is a valve return pulse output circuit, in which the switching transistor circuit Q2 connected between the power supply circuit 31 and the terminal 30d is turned on and off by a signal applied to its base.
Approximately 20V between terminals 30d and 306 when turned off and on
Outputs the voltage of

This 20V voltage becomes a valve opening signal.

Reference numeral 37 denotes a gas leakage signal determination circuit, which determines that there is a gas leakage signal when the voltage signal applied from the detector 10 to the terminal 30C is equal to or higher than the approximately 7.5V determination voltage from the Zener diode ZD, and detects this. Inverter 37 according to
Change the output of a from H to L level.

Reference numeral 38 denotes a self-inflicted act signal discrimination circuit, which detects that the voltage signal applied from the detector 10 to the terminal 30C is OV and determines that it is a self-inflicted act signal, and in response, the NAND circuit The output of inverter 38a is changed from L to H level, and the output of inverter 38b is changed from H to L level.

39 is an external device output circuit, which is usually the above-mentioned discrimination circuit 38.
The output of the NAND circuit 38a inside is at L level, the transistor circuit Q3 is turned on, and the transistor circuit Q4 is turned on.
．． ．． A constant voltage of about 6 cm set by Q5 is output from terminals 30i and 303 through transistor circuit Q3. When determining the self-inflicted act signal, the output of the NAND game 1.38a is 11 levels, and the L transistor circuit Q3 is turned off, so the output voltage of the terminals 3Qi and 30j becomes O■. When the gas leak signal is determined, the output of the inverter 37H becomes L level and the transistor circuit Q3 is turned on, so that the approximately 12V voltage applied to the terminal 30C at this time is directly transmitted to the terminals 30i and 30j through the transistor circuit Q3. is output from.

40 is a buzzer drive circuit; 41 is a buzzer driven by the circuit; circuit 40 is connected to circuit 3 when determining a gas leak signal;
When the output of the inverter 37a of No. 7 reaches the I7 level, the internal oscillation circuit oscillates, causing the buzzer 41 to sound.

42 is a power supply interruption detection circuit, and when the power supply to the device is cut off due to a power outage or a breaker tripping, the inverter 42
The output of a changes from L to H level.

43 is a breaker disconnection detection circuit, and when the auxiliary terminal 22 of the breaker that supplies power to the device (turns on when the breaker is on) is connected between terminals 30g and 30h as shown by the dotted line, the auxiliary terminal 44 is on, the output of the inverter 42a is grounded and the function of the circuit 42 is disabled.

Then, by turning off the auxiliary terminal 44, the capacitor C2 is charged by the bank amplifier power supply, and the output of the inverter 43a changes from the H level to the L level.

When the auxiliary terminal 44 is not connected to the terminals 30g and 30h, the inverter 42a is connected to the power supply Nu
Since the output of inverter 43a becomes H level, the output of inverter 43a changes from H level to L level accordingly.

45 is a 60 second delay circuit, and the circuit 37 determines the gas leak signal and changes the output of the impark 37a from H to L.
level, or when @1i83B determines the self-inflicted act signal and the output of the inverter 38b changes from H to 1 level, the output of the inverter 45a changes from L to H level, and this causes the capacitor C3 to resist the resistance. R1
, R2. When the charge level of capacitor C3 exceeds a predetermined value, programmable unijunction transistor PUTI turns on and rapidly discharges the charge of capacitor C3 through resistor R2, thereby causing P
UTI is turned off again. At this time, the output of the inverter 45b changes from H level to L level due to PUTI being turned on, and P
When the UTI is turned off, it goes to L Kara I (level) and outputs an L level pulse.

Then, capacitor C3 is charged again when PUT 1 is turned off, but the time constant by R+, R2, and C3 is set so that it takes about 40 seconds until PUT' 1 is turned on again. One L level pulse is generated at the output of inverter 45b every approximately 40 seconds until C3 is no longer charged.

46 is monostable multi-by-break (one-shot circuit)
46a, and when a pulse of level I generated at the output of the inverter 45a is applied to the trigger input of the one-shot I circuit 4.62, its output, which is normally at H level, is becomes L level for a certain period of time, and this is inverted by inverter 46b and output as an H level pulse. The output of this pulse generating circuit 46 is connected to the base of the transistor circuit Q1 of the cutoff valve output circuit 35, and turns off the transistor circuit Q1 while the pulse at the I(level) continues. 30d.

The voltage applied from 30e to the shutoff valve 20a changes from 6■ to O■ during the pulse period and returns to 6■ again.

Reference numeral 47 designates an anzabank circuit, to which the terminal 30f of the reed switch 24 of the cutoff valve 20a is connected as shown by a dotted line. The reed switch 24 is on when the cutoff valve 20a is open, but the OV from the cutoff valve output circuit 35
When the cutoff valve 20a is closed by application of the main voltage, it is turned off.

When the reed switch 24 is turned off, the output of the inverter 47a changes from H level to L level.

The output of this inverter 47a is connected via a diode D to a connection point between resistors R1 and R2 of the circuit 45. Therefore, when the output of the inverter 47a reaches the 4I7 level, the capacitor C3 is no longer charged, and an L level pulse is no longer generated at the output of the inverter 45b, and the one-shot circuit 46
Trigger a will no longer be triggered.

By the way, the answer pack circuit 47 has one toss isochi 24.
If the line connecting the inverter 47a is cut off for some reason, the output of the inverter 47a remains at level I even if the cutoff valve 20a is open, just as if the valve were closed. Therefore, even if a gas leak or self-damage signal is determined, the capacitor C3 will not be charged. In this case, since the L level of the output of the inverter 47a is applied to one input of the NAND circuit 46c, the L level of the output of the inverter 45a is applied to the other input of the NAND circuit 46C in accordance with the H level of the output of the inverter 45a by the second signal discrimination. When the output of the connected inverter 46d becomes level ■, the output of the NAND circuit 46C changes from L to H level, and in response, L and \ pulses are generated at the output of the inverter 45b. It becomes like this. Therefore, the output of the circuit 46a is triggered by the L level pulse and generates an L level pulse at its output.

This pulse is inverted to turn off the one-herald transistor circuit Q1 for the pulse period, so that a cutoff signal is generated, albeit only once.

Reference numeral 48 denotes a 5-minute timer circuit composed of a counter circuit, and the output of the breaker disconnection detection circuit 43 is connected to the input of the resetting 1 circuit, and the circuit 48 is in the resetting state while the human power level is at the H level. , the reset is canceled and the start is started. 5 minute recess 1-
If there is no human power, an L-level pulse is generated at its output and applied to the trigger input of the one-shot circuit 46a. Therefore, a cutoff signal can be generated 5 minutes after the power supply is cut off or the breaker is cut off.

49 is a 40-second delay circuit, which creates a 40-second delay for returning the shutoff valve 20a approximately 40 seconds after the gas leakage and self-injury signals disappear and the compressed state returns. Due to the return to the compacted state, Inhark 45
When the output of the inverter 46d changes from the H level to the L12 level, the output of the inverter 46d changes from the L level to the H level, and the transistor circuit Q6 is turned on. As a result, capacitor C3 is charged via resistors R3 and R4, and when the level exceeds a predetermined value after about 40 seconds, P
UT2 turns on. By turning on PUT2, the output of the inverter 49a, which had been at I level, temporarily becomes L level.

50 is a pulse generation circuit consisting of a one-shot circuit 50a and an inverter 50b, and when a pulse of level I is inputted from the delay circuit 49 to the trigger input of the one-shot circuit, the output becomes the H level for about 2 seconds. occurs. This pulse is inverted by the inverter 50b, and the transistor circuit Q2 of the valve return pulse output circuit 36 is inverted.
is applied to the base of the transistor circuit Q.
2 turns on for 2 seconds. By this, the terminal 30d,
A valve opening signal of about 20V is supplied to the shutoff valve 20a through the voltage line 30e, and the shutoff valve 20a is opened. By opening this valve,
The reed switch 24 is turned on 76 again.

51 is a manual cutoff switch circuit, and when the output of the inverter 51a becomes L level by turning off the switch 30p, it is directly applied to the pulse generation circuit 46 through the capacitor C4.

Therefore, when the switch 30p is turned off, a cutoff signal is immediately generated and the cutoff valve 20a is closed.

However, if the valve does not close for some reason, the output of the inverter 45a is at the [■] level at this time, so the one-shot circuit 46a continues to be triggered until the valve is closed. When this switch 30p is returned to its original on state, a valve return pulse is generated in the same manner as in the above case.

52 is an initial reset circuit, and a one-shot circuit 46
a, 50a are reset at the start of energization to prevent unnecessary valve shutoff signals and valve return signals from being generated.

As explained above, according to the present invention, the shutoff signal that closes the gas cutoff valve is generated repeatedly intermittently until the valve close signal generated when the gas cutoff valve is closed is received. Even if the movement of the valve body is not smooth and may become mechanically stuck for some reason, it can be reliably closed by repeatedly applying the shutoff signal, resulting in a highly safe device.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing a conventional gas leak detector interlocking shutoff system, FIG. 2 is a diagram schematically showing the same system using the device according to the present invention, and FIG. 3 is a rear view of the device according to the present invention. FIG. 4 is a circuit diagram of a gas cutoff valve used in the system of FIG. 2, and FIG. 5 is a circuit diagram showing details of the circuit configuration of the apparatus according to the invention. 10... Gas leak detector, 20a...
Gas cutoff valve, 24... Reed switch, 45.
...1 minute delay time i, 46...pulse generation circuit, 47...anza hasok circuit, C3...
...Capacitor, PUTI...Programmable unijunction transistor.

Claims (1)

[Claims] In a gas cutoff valve control device that generates a cutoff signal to close a gas cutoff valve in response to a gas leakage signal generated by a gas leakage detector, a valve close signal generated by the gas cutoff valve in response to the valve closing is inputted. A gas cutoff valve control device comprising a cutoff signal generation circuit means for intermittently and repeatedly generating the cutoff signal in response to the gas leakage signal.