JPH0229412Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field] The present invention relates to an automatic gas flow path shutoff device that can automatically shut off a gas flow path such as a gas pipe when a gas leak is detected or a fire occurs. .

[Background Art] Conventionally, a gas flow path automatic shutoff device has been put into practical use, which combines a gas leak detector and a gas circuit breaker to automatically shut off the gas flow path when a gas leak is detected. By the way, in this type of gas flow path automatic shutoff device, if the solenoid that drives the gas circuit breaker is disconnected or the gas circuit breaker is disconnected, the gas circuit breaker will not be able to operate.
Even if a gas leak occurs, the gas flow path is not blocked, which is dangerous. To prevent such dangers,
It is desired to notify that a gas circuit breaker is inoperable.

[Purpose of the invention] This invention was made in view of the above-mentioned points.
It is an object of the present invention to provide an automatic gas flow path shutoff device that can notify when a gas circuit breaker becomes inoperable due to a disconnection of the gas circuit breaker.

[Disclosure of the invention] Hereinafter, the configuration of the invention will be explained with reference to an illustrated embodiment. As shown in the block diagram of FIG. A gas circuit breaker that has a gas circuit breaker 3 that automatically shuts off the circuit, and input terminals I ₁ and I ₂ that input the detection output of the gas leak detector 1, and that energizes the gas circuit breaker 3 when there is a gas leak detection output. In the gas flow path automatic shutoff device comprising a drive device 2, the gas leak detector 1 is of a voltage output type in which the output voltage changes between detection and non-detection, and the gas leak detector 1 is The output voltage is applied to the gas circuit breaker drive device 2 as a power source, and the gas circuit breaker drive device 2 is provided with a comparator which is a display unit that can set two types of display states: continuous lighting that is always on and intermittent lighting that repeats blinking. CP ₁ and light emitting diode
Output terminal equipped with LED and connected to gas circuit breaker 3
The display state of the display section is selectively set depending on whether there is continuity or non-conduction between T ₁ and T ₂ , and with this configuration, the solenoid L that drives the gas circuit breaker 3 can be disconnected. When the gas circuit breaker 3 becomes inoperable due to the gas circuit breaker 3 being disconnected from the output terminals T ₁ and T ₂ , the light emitting diode LED
The lighting state of the lamp changes to notify the user.

In this embodiment, the gas circuit breaker driving device 2 is provided with input terminals I ₃ and I ₄ to which detection outputs from detectors such as the fire detector 4 other than the gas leak detector 1 are input,
The gas circuit breaker 3 is energized when there is a detection output from other detectors such as the fire alarm 4, and the gas circuit breaker 3 is energized not only when a gas leak occurs but also when a fire occurs. This allows the gas flow path to be shut off.

FIG. 2 is a circuit diagram showing a more specific circuit configuration of this embodiment. In the figure, 1 is a voltage output type gas leak detector, 2 is a gas leak alarm connected to the detection output of the gas leak detector 1,
3 is a gas circuit breaker that blocks the gas flow path. The gas leak detector 1 generates a voltage output of 6V during normal times, and generates a voltage output of 12V when detecting a gas leak. Furthermore, when the power of the gas leak detector 1 is cut off or the line connecting the gas leak detector 1 and the gas circuit breaker drive device 2 is disconnected, a voltage of 0V is input to the gas circuit breaker drive device 2. ing. The input terminal I ₁ of the gas circuit breaker driving device 2 is a positive input terminal, and the input terminal I ₂ is a negative input terminal. In the circuit of gas circuit breaker drive device 2, the power line is connected to diode D ₁
It is connected to the input terminal _I1 via the ground line, and the ground line is directly connected to the input terminal _I2 . The input voltage applied between input terminal I ₁ and input terminal I ₂ is applied via diode D ₁ to a voltage divider circuit made up of resistor R ₄ and resistor R ₅ . The resistance values of resistor R ₄ and resistor R ₅ are the same value,
The input voltage is divided into half. The voltage divided by the resistor R ₄ and the resistor R ₅ is applied to the positive input terminal of the comparator CP ₁ . A positive feedback resistor _R2 is connected between the output terminal of the comparator _CP1 and the positive input terminal to provide hysteresis characteristics. A light emitting diode is connected between the output terminal of comparator CP ₁ and the ground line to indicate operation.
The LED is connected through a current limiting resistor _R1 . The output terminal of the comparator CP ₁ and the negative input terminal are connected via a high resistance R ₃ .
In addition, a capacitor C ₂ is connected between the negative input terminal of the comparator CP ₁ and the earth line, and when the transistor Tr ₁ connected in parallel to this capacitor C ₂ is off, the resistor
The comparator CP ₁ performs an oscillating operation at a period determined by the time constant of R ₃ and the capacitor C ₂ , and the light emitting diode LED is driven in dimming mode. Further, the voltage applied between the input terminals I ₁ and I ₂ is divided by a resistor R ₉ and a resistor R ₈ and is applied to the base of the transistor Tr ₂ . The collector of the transistor Tr ₂ is connected to the power supply line via a resistor R ₁₀ and input terminals I ₃ and I ₄ . The input terminals I ₃ and I ₄ are input terminals to which a non-voltage output type detector such as the fire detector 4 is connected. Furthermore, the collector of transistor Tr ₂ is connected to the base of transistor Tr ₃ . There is a resistor between the power line and the ground line.
A voltage divider circuit consisting of _R13 and a resistor _R11 is connected, and the divided voltage of this voltage divider circuit is applied to the positive input terminal of the comparator _CP2 . Furthermore, an integrating circuit consisting of a high resistance R ₁₂ and a capacitor C ₃ is connected between the power supply line and the earth line, and the integrated output of this integrating circuit is applied to the negative input terminal of the comparator CP ₂ . There is. Further, a transistor Tr ₃ is connected in parallel to the capacitor C ₃ of the integrating circuit. A positive feedback resistor _R14 for latching the comparator _CP2 is connected between the output terminal and the positive input terminal of the comparator _CP2 . The output terminal of comparator CP ₂ is connected to the base of transistor Tr ₄ via resistor R ₁₅ . The gas circuit breaker drive device 2 has output terminals T ₁ and T ₂ connected to the gas circuit breaker 3. One output terminal T ₁ is directly connected to the power supply line, and the other output terminal T ₂ is connected to the earth line via a Zener diode ZD ₁ . A transistor Tr ₅ is connected in parallel to both ends of the Zener diode ZD ₁ . A resistor _R18 is connected in parallel between the base and emitter of the transistor _Tr5 . Also, the base of transistor Tr ₅ is connected to resistor R ₁₇ and transistor Tr _4.
and is connected to the connection point between resistor R ₁₂ and capacitor C ₃ . A diode D ₂ is connected in parallel between the output terminals T ₁ and T ₂ in a direction opposite to the voltage application direction. Furthermore, a relatively large capacity capacitor _C1 is connected in parallel between the power supply line and the earth line. Output terminal of gas circuit breaker drive device 2
A gas circuit breaker 3 is connected between T ₁ and T ₂ , and this gas circuit breaker 3 has a solenoid L and a reed switch SW that shut off the gas flow path.

Next, the operation of this embodiment will be explained. first,
In normal times when there is no gas leak or fire, a voltage output of 6V is generated from the voltage output type gas leak detector 1, and the contact of the non-voltage output type fire detector 4 is in the on state. It's summery. At this time, the transistor Tr ₂ is off and the transistor Tr ₃ is on. Therefore, the charging voltage of the capacitor _C3 has become low, and therefore the voltage applied to the negative input terminal of the comparator _CP2 has become low. _The voltage applied to the positive input terminal of comparator CP ₂ is determined by the voltage divided by resistor R ₁₃ and resistor R ₁₁ .
and resistor R ₁₁ have the same low resistance value, so the voltage applied to the positive input terminal of comparator CP ₂ is equal to the voltage applied between the power supply line and the earth line (approximately 6V) divided by half. However, this voltage is higher than the voltage applied to the negative side of comparator CP ₂ , so the comparator
The output terminal of CP ₂ becomes high level, and the transistor Tr ₄ is turned off. When the transistor Tr ₄ is off, no base current flows through the transistor Tr ₅ , so the transistor Tr ₅ is turned off.
The zener voltage of the zener diode ZD ₁ connected in parallel with the transistor Tr ₅ is set to about 6V, so the gas circuit breaker 3 does not operate under normal conditions.

Next, when the voltage output type gas leak detector 1 detects a gas leak, the gas leak detector 1
A voltage output of 12V is generated, and in this case, the resistors R _{9 and} Tr _{2 are connected so that the transistor Tr 2} is turned on.
The value of _R8 has been adjusted. When transistor Tr ₂ turns on, transistor Tr ₃ turns off and capacitor C ₃ starts charging. The time constant of the integrating circuit consisting of capacitor C ₃ and resistor R ₁₂ is set to a value that does not cause comparator CP ₂ to malfunction when the voltage at input terminals I ₁ and I ₂ temporarily increases due to noise voltage. ing. Therefore, when the voltage of the capacitor _C3 becomes higher than the voltage applied to the positive input terminal of the comparator _CP2 , the output terminal of the comparator _CP2 becomes a low level. Once the output voltage of comparator CP ₂ becomes low level, the voltage applied to the positive input terminal of comparator CP ₂ decreases via the positive feedback resistor R ₁₄ , so the output voltage of comparator CP ₂ latches to low level. will be done. This turns on transistor Tr ₄ and
Tr ₅ is also turned on. Therefore, the charging voltage of the capacitor _C1 is applied to the gas circuit breaker 3, and the gas flow path is cut off.

Furthermore, when a fire occurs and the contact of the non-voltage output type fire detector 4 is turned off, the base voltage of the transistor Tr ₃ becomes low level, so the transistor Tr ₃ is turned off. Therefore, in this case as well, the charging voltage of the capacitor C ₃ starts to rise, and the gas circuit breaker 3 cuts off the gas flow path in the same manner as when the gas leak detector 1 operates. It is.

By the way, the input terminal I ₁ of the gas circuit breaker drive device 2,
The values of the resistors R ₆ and R ₇ are set so that the transistor Tr ₁ turns on when a voltage of 6 V or 12 V is applied between I ₂ . When the transistor Tr ₁ is on, the voltage applied to the negative input terminal of the comparator CP ₁ becomes extremely low. On the other hand, since a relatively high voltage divided by resistors R ₄ and R ₅ is applied to the positive input terminal of comparator CP ₁ , the output voltage of comparator CP ₁ becomes high level, and the light emitting diode
The LED lights up. In addition, in order to check the operation, the gas circuit breaker 3 is connected to the output terminal of the gas circuit breaker drive device 2.
When removed from T ₁ and T ₂ , transistor Tr ₁
is turned off, and comparator _CP1 performs an oscillating operation. In other words, when the output voltage of comparator CP ₁ is at high level, the capacitor
C ₂ is gradually charged through high resistance R ₃ and its charging voltage increases. This makes the comparator
When the voltage applied to the negative input terminal of CP ₁ becomes higher than the voltage applied to the positive input terminal, the output voltage of comparator CP ₁ becomes low level. Comparator CP ₁ has a positive feedback resistor R ₂ to provide hysteresis characteristics, so once the output voltage becomes low level, the voltage applied to the positive input terminal becomes low, and therefore comparator CP ₁ The output voltage of is held at low level. When the output voltage of the comparator _CP1 becomes low level, the charge in the capacitor _C2 is discharged through the high resistance _R3 , and the charge voltage in the capacitor _C2 gradually decreases. Then, when the charging voltage of the capacitor _C2 becomes lower than the voltage applied to the positive input terminal of the comparator _CP1 , the output voltage of the comparator _CP1 returns to the high level. Once the output voltage of comparator CP ₁ returns to high level, comparator CP ₁
The output voltage of the comparator _CP1 is held at a high level due to the hysteresis characteristic of the comparator CP1. Thereafter, the same operation is repeated so that the output voltage of the comparator _CP1 becomes high level or low level at regular intervals, and thereby the light emitting diode LED performs a blinking operation.
The blinking period of the light emitting diode LED is determined by the time constant of the high resistance _R3 and the capacitor _C2 . In this way, when the gas circuit breaker 3 is removed from the output terminals T ₁ and T ₂ of the gas circuit breaker drive device 2, the light emitting diode LED changes from continuous lighting to intermittent lighting. In other words, when the output terminals T ₁ and T ₂ are electrically connected, the lighting is continuous, and when there is no electrical continuity, the lighting is intermittent, so if the solenoid L that drives the gas circuit breaker 3 is disconnected or the If the gas circuit breaker 3 is disconnected from the output terminals T ₁ and T ₂ , the lighting state of the light emitting diode LED changes, and it is possible to notify that the gas circuit breaker 3 is inoperable. Note that if the reed switch SW connected in series with the solenoid L is configured to operate in conjunction with the solenoid L so that when the gas circuit breaker 3 operates, the gas flow path is shut off and the reed switch SW is opened at the same time. Blockage of the flow path can also be detected by blinking the light emitting diode LED.
Furthermore, as described above, the gas leak detector 1 is a voltage output type, and the output voltage is applied to the gas circuit breaker drive device 2 as a power source. deviate from 2,
If the line between the gas leak detector 1 and the gas circuit breaker drive device 2 is disconnected, the light emitting diode
The LED turns off, and from this, it is possible to know that there is an abnormality in the gas leak detector 1.

In the explanation of the embodiment, a non-voltage contact output type fire detector 4 is used as a detector other than the gas leak detector 1, but this is different from a voltage output type fire detector. It is okay to use. In this case, the voltage output of the fire detector should be connected to the resistor.
applied to the base of transistor Tr ₃ through R ₁₀ ,
It is sufficient that _the transistor Tr ₃ is turned on during normal times, and turned off during abnormal times. Further, the other detectors mentioned above are not necessarily limited to fire detectors, but other gas leak detectors may also be connected.

[Effects of the invention] The invention is constructed as described above, and includes a gas leak detector that detects the occurrence of gas leaks, a gas circuit breaker that automatically shuts off the gas flow path when electricity is applied, and a gas leak detector that detects gas leaks. In a gas flow path automatic shutoff device, the device includes a gas circuit breaker drive device that receives the detection output of a gas leak detector and energizes the gas circuit breaker when there is a gas leak detection output. In addition to using a voltage output type in which the output voltage changes over time, the output voltage of the gas leak detector is applied as a power source to the gas circuit breaker drive device, and the gas circuit breaker drive device has continuous lighting and blinking. A display section is provided that can be set to two types of display states: repeated intermittent lighting, and the display state of the display section can be selectively set depending on whether there is continuity or non-conduction between the output terminals connected to the gas circuit breaker. If the internal circuit of the gas circuit breaker is disconnected or the gas circuit breaker is disconnected from the output terminal and the gas circuit breaker becomes inoperable, the lighting status of the display will change. , the user can be notified of the malfunction of the device, and the user can easily discover the malfunction of the device and take prompt action. As a result, the gas circuit breaker can be made to operate reliably at all times, increasing safety. Furthermore, since the gas leak detector is a voltage output type and the output voltage of the gas leak detector is applied to the gas circuit breaker drive device as a power source, the gas leak detector can be disconnected from the gas circuit breaker drive device. At times, the display section turns off, and this operation allows the user to know that there is an abnormality in the gas leak detector, making it even more reliable to discover the malfunction. In short, one display can display three states: when there is no failure, when there is a failure in the gas leak detector, and when there is a failure in the gas circuit breaker. can be easily discovered.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention, and FIG. 2 is a circuit diagram showing a more specific circuit configuration of the same. 1 is a gas leak detector, 2 is a gas circuit breaker drive device, 3 is a gas circuit breaker, 4 is a fire detector, CP ₁ is a comparator, and LED is a light emitting diode.

Claims (1)

[Scope of utility model registration request] A gas leak detector that detects the occurrence of gas leaks,
A gas circuit breaker that automatically shuts off the gas flow path when energized, and a gas circuit breaker drive device that has an input terminal for inputting the detection output of a gas leak detector and energizes the gas circuit breaker when there is a gas leak detection output. In a gas flow path automatic shutoff device comprising:
The gas leak detector is a voltage output type in which the output voltage changes between detection and non-detection, and the output voltage of the gas leak detector is applied as a power source to the gas circuit breaker drive device. The display section is equipped with a display section that can be set to two types of display states: continuous lighting that is always on and intermittent lighting that repeatedly flashes. A gas flow path automatic shutoff device characterized in that a display state is selectively set.