JPS649031B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas piping monitoring device for monitoring abnormalities in gas supply systems in homes, factories, and the like.

``Prior art'' Conventionally, this type of device was
As shown in No. 116941, a solenoid valve is installed upstream of the gas piping, and an in-pipe pressure detector is placed downstream of the solenoid valve to detect gas pressure in the pipe and open/close a pressure switch. When the valve start switch is turned on, the solenoid valve is opened for a certain period of time and then closed.After the solenoid valve is closed, the pressure inside the pipe is detected by the pressure change within a certain period of time, and the pressure is set. A circuit that closes the pressure switch and opens the solenoid valve again when the value is maintained at an abnormal value, and when the pressure drops below the set pressure, the pressure switch opens and the solenoid valve remains closed and an alarm is issued. A device comprising the following has been proposed. Additionally, this document further states that when the device is stopped, when the stop switch is closed, the solenoid valve is closed, and after the solenoid valve is closed, the pressure change within a certain period of time is detected by the pipe pressure detector to determine the set pressure. It is also proposed that a circuit be added that would issue an alarm if the aeroplane descends below this level.

``Problems to be Solved by the Invention'' However, in conventional gas pipe monitoring devices of this type, the start switch of the solenoid valve is turned ON when the device is started (gas use), and the stop switch is closed when the device is stopped (gas use is finished). The gas piping can only be monitored if the system is properly operated (by turning on a stop switch that is separate from the start switch, or by turning the start switch OFF), and even if the gas usage is finished, the stop switch will still be turned on. had the disadvantage that it would be impossible to monitor the gas piping unless it was closed.

In addition, this conventional device attempts to detect piping defects, or in other words, the presence or absence of gas leaks, based on changes in gas pressure that are closed downstream from the solenoid valve, but in actual results, Changes in the pressure of the gas closed on the downstream side are greatly affected by the internal volume of the pipe downstream of the solenoid valve, changes in the ambient temperature, etc., so in order to accurately detect small gas leaks, the solenoid valve must be closed before starting the equipment. It was found that it was necessary to open the solenoid valve once, set the supply gas pressure downstream from the solenoid valve, close the solenoid valve, and then measure the change in gas pressure in the pipe over a long period of time. For example, in a normal city gas supply system, there is a
If a 15M pipe were connected, it would take more than 10 minutes to monitor the pressure change prior to use, making it inconvenient to use gas. On the other hand,
If you set a long time to monitor changes in closed gas pressure in order to reliably detect gas leaks, when you finish using a gas stove in a cold region, the gas pressure may drop due to changes in room temperature, causing damage to the pipes. An abnormality will be detected even though there is no defect.

Therefore, the present invention was made to solve the above-mentioned drawbacks, and it is possible to detect the end of gas use and automatically turn off the start switch, thereby accurately monitoring gas piping without causing any inconvenience to gas use. The purpose of this invention is to provide a gas piping monitoring device that can perform the following tasks.

"Means for Solving the Problems" In line with the above-mentioned object, the configuration of the present invention, the gist of which is defined in the preceding claims, is such that the upstream portion of the gas pipe 1 is connected to the gas pipe 1. A solenoid valve 2 that opens and closes gas supply to the downstream side of the solenoid valve 2 is disposed downstream of the solenoid valve 2, and a gas pressure detector 3 that detects a change in gas pressure in the pipe as a change in voltage value is disposed downstream of the solenoid valve 2. has an input end 11 of the gas pressure detector 3, a start switch 12 that turns ON when gas is used and turns OFF when gas use is finished, a reset switch 17, and an alarm display section 13, and furthermore, A memory circuit 14 that stores the input voltage from the gas pressure detector 3 at that time every time the solenoid valve 2 closes when the start switch 12 is turned off, and a memory circuit 14 that stores the stored value of the memory circuit 14 and the subsequent gas pressure detector 3. 3
A comparison circuit 15 that compares the voltage value of 12 is turned on, the comparison circuit 15 compares the input voltage from the gas pressure detector 3 at that point with the previous input signal from the gas pressure detector 3 stored in the memory circuit 14. Therefore, the comparison circuit 1 is applied only when there is no voltage drop.
5 outputs an energizing signal to the solenoid valve power supply circuit 16 to open the solenoid valve 2, and also, when the solenoid valve 2 is energized, the gas pressure detector 3
When the input voltage of the solenoid valve 2 decreases by more than a certain percentage than the voltage value stored in the memory circuit 14, the comparator circuit 15 outputs a energization cutoff signal to the solenoid valve power supply circuit 16 to close the solenoid valve 2. If the input voltage from the gas pressure detector 3 is the same as the memorized voltage value for a certain period of time in the energized state, a signal to cut off the energization is output from the comparison circuit 15 to the solenoid valve energizing circuit 16, and the solenoid valve 2 is closed for a certain period of time. When the input voltage from the gas pressure detector 3 drops below the memorized voltage value, the comparator circuit 15 outputs an energizing signal to the solenoid valve power supply circuit 16 to immediately open the solenoid valve 2, and the gas remains open even after a certain period of time has passed. If the input voltage from the pressure detector 3 does not drop below the voltage value stored in the memory circuit 14, the starting switch 12 is automatically turned off. Also, when the starting switch 12 is turned off, the comparator circuit 15 A signal to cut off the energization is output to the solenoid valve power supply circuit 16, and then, when the input voltage from the gas pressure detector 3 falls below the previous stored value stored in the memory circuit 14 within a certain period of time, the alarm display section 13 is energized. In addition to issuing an alarm, the solenoid valve power supply circuit 16
The current is electrically locked in the cut-off state, and when the input voltage from the gas pressure detector 3 decreases after a certain period of time has passed, the solenoid valve 2 is opened once, the downstream side is set to the supply gas pressure, and the comparison is made again. The circuit 15 compares the input voltage within a certain period of time with the stored value, and when the reset switch is turned on, the electrical lock is released and the alarm display section 13
The start switch 12 is then turned off.
When turned on, the solenoid valve power supply circuit 16 opens the solenoid valve 2 for a certain period of time, and the voltage value of the gas pressure detector 3 after a certain period of time after the solenoid valve 2 closes is compared with the value stored in the storage circuit 14 and the comparison circuit 15 If a voltage drop is detected by comparison, the alarm display unit 13 is notified again and the solenoid valve power circuit 16 is electrically locked in the energized state. If no voltage drop is detected, the solenoid valve power circuit 16 is energized again. This is a technical measure in which a control panel 10 is connected to output a signal to open the solenoid valve 2.

``Function'' Therefore, in the gas piping monitoring device of the present invention, when the start switch 12 is turned ON when starting to use gas, the input from the gas pressure detector 3 is lower than the value previously stored in the storage circuit 14. If not, it is determined that no piping failure has occurred before then, and the solenoid valve 2 is immediately energized to make the gas usable.

Further, even when the solenoid valve 2 is energized, if the effective voltage from the gas pressure detector 3 does not change from the memorized voltage for a certain period of time, the comparator circuit 15 sends a signal to the solenoid valve power supply circuit 1.
A signal to cut off the power is output to 6, and if the solenoid valve 2 is closed and the input voltage from the gas pressure detector 3 does not drop, it will be determined that gas is not being used and the starter switch 12 has been forgotten to be turned off, and the starter switch 12 will be automatically turned off. to
OFF and eggplant.

Further, when the energization of the solenoid valve 2 is completed, an after-use inspection is performed, and if an abnormality is detected, the solenoid valve 2 is locked.

Furthermore, if an abnormality is detected through the above inspection,
By turning on the reset switch 17, the solenoid valve 2 is unlocked, and then the starting switch 12 is turned on.
When set to ON, it shifts to inspection confirmation operation before use.
Inspection and monitoring of piping is performed over a certain period of time.

"Embodiments" Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

In the figure, 1 is a gas pipe, and the upstream end of this gas pipe 1 is connected to a gas supply source (not shown) (an outdoor end for city gas, a gas cylinder for propane gas, or an outlet of a gas meter connected to these). , a conventionally known gas supply system to which a gas appliance F is connected is formed on the downstream side. It goes without saying that the gas pipe 1 may be one that is already installed in a home, factory, or the like.

An electromagnetic valve 2 for opening and closing gas supply to the downstream side of the gas pipe 1 is disposed at an upstream portion of the gas pipe 1. This solenoid valve 2 opens only when energized and supplies gas to the downstream side, that is, to the gas appliance F, and gas is not supplied downstream from this solenoid valve 2 at all times when the energization is cut off. .

A gas pressure detector 3 is disposed downstream of the electromagnetic valve 2 in the gas pipe 1 to detect changes in gas pressure within the pipe as changes in voltage value. This gas pressure detector 3 is a so-called strain gauge in which a material whose resistance value changes with strain is laminated on a flexible substrate.One side of this strain gauge is placed inside the gas pipe 1, and the other side is placed in the atmosphere. It is configured so that it faces to the side.

A control panel 10 is connected to the electromagnetic valve 2 to control opening and closing of the electromagnetic valve using a detection signal outputted from the gas pressure detector 3. This control panel 10 has a circuit configuration as shown in Fig. 2, and includes an input terminal 11 of the gas pressure detector 3, a start switch 12 that turns on when gas is in use, and turns off when gas is finished, and a reset switch. Switch 17 and
Further, a memory circuit 14 stores the input voltage from the gas pressure detector 3 at that time each time the solenoid valve 2 closes when the start switch 12 is turned off; a comparison circuit 15 that compares the stored value of 14 with a subsequent voltage value from the gas pressure detector 3; and a solenoid valve power supply circuit that opens and closes the energizing circuit to the solenoid valve 2 based on a signal output from the comparison circuit 15. It has 16 internal organs.

The output end of the gas pressure detector 3 is connected to the input end 11, and a voltage that changes according to the gas pressure in the gas pipe 1 is input from the gas pressure detector 3 as an in-pipe gas pressure signal. It's getting old. This in-pipe gas pressure signal is amplified by an amplifier circuit 18 and converted into a digital signal by an A/D conversion circuit 19.
The output terminal of 9 is connected to the memory circuit 14 via the branch point P1.
The output terminal of the storage circuit 14 is connected to the storage signal input terminal of the comparison circuit 15.

The output terminal of an ON state memory circuit 12a connected to the output terminal of the start switch 12 is connected to the memory circuit 14, and each time the ON state memory circuit 12a is reset, the output terminal of the ON state memory circuit 12a is stored. (Preferably after a few seconds to stabilize the gas pressure in the pipe)
Then, the input voltage from the gas pressure detector 3 is stored again, and this stored value is output to the comparison circuit 15 until the next new input voltage is stored.

Further, the comparison circuit 15 is connected to the output terminal of the ON state memory circuit 12a and also houses a timer function. connected to the input terminal of the circuit 16, and also connected to the input terminal of the comparison circuit 15.
Other output terminals are connected to the input terminals of the prohibition circuit 20 and the alarm display unit 13, respectively, which maintain the solenoid valve power supply circuit 16 in a state of de-energization until the next reset signal is input by the signal input from the comparison circuit 15. It is connected.

Then, when starting to use the gas, the start switch 12 is activated.
When turned on, the comparison circuit 15 compares the input voltage from the gas pressure detector 3 at that point with the previous input signal from the gas pressure detector 3 stored in the memory circuit 14. Only when there is no voltage drop, the comparator circuit 15 outputs an energizing signal to the solenoid valve power supply circuit 16 to open the solenoid valve 2.

In addition, when the solenoid valve 2 is energized, the gas pressure detector 3
When the input voltage of the solenoid valve 2 decreases by more than a certain percentage than the voltage value stored in the memory circuit 14, the comparator circuit 15 outputs a energization cutoff signal to the solenoid valve power supply circuit 16 to close the solenoid valve 2. If the input voltage from the gas pressure detector 3 is the same as the memorized voltage value for a certain period of time in the energized state, a signal to cut off the energization is output from the comparison circuit 15 to the solenoid valve energizing circuit 16, and the solenoid valve 2 is closed for a certain period of time. When the input voltage from the gas pressure detector 3 falls below the memorized voltage value within a certain period of time, the comparator circuit 15 outputs an energizing signal to the solenoid valve power supply circuit 16 to immediately open the solenoid valve 2, and even after a certain period of time has elapsed. If the input voltage from the gas pressure detector 3 does not fall below the memory voltage value of the memory circuit 14, the comparison circuit 15
A reset signal is output to the ON state memory circuit 12a, so that the starting switch 12 is automatically turned off appropriately. In addition, this start switch 12
is a push button type; press it once to turn on the switch.
Pressing the signal a second time turns on the switch OFF signal.
Although the starting switch 12 is designed to output the ON state signal, the ON state storing circuit 12a may be connected to a manual switch (not shown) exclusively for outputting the OFF signal.

In addition, when the solenoid valve 2 is energized, the gas pressure detector 3
If the input voltage of the gas pipe 1 decreases by more than a certain percentage than the voltage value stored in the memory circuit 14, a large amount of gas leakage such as a hose disconnection is expected.
When the gas pressure in the pipe decreases at a rate greater than when all of the gas appliances F connected to the pipe are used at once, the comparator circuit 15 considers it to be a gas leak and closes the solenoid valve 2. .

In addition, if the input voltage from the gas pressure detector 3 is the same as the memorized voltage value for a certain period of time while the solenoid valve 2 is energized, the start switch 12 is activated even though gas is not used.
This may be the case if you do not turn it off.
Therefore, if the input voltage from the gas pressure detector 3 is the same as the voltage value stored in the memory circuit 14 for a certain period of time, for example, one hour, it is assumed that the starter switch 12 has been turned off and the solenoid valve 2 is closed. After that, within a certain period of time (e.g.
20 seconds), when the input voltage from the gas pressure detector 3 falls below the memorized voltage value, this means that gas is in use, so the comparator circuit 15 outputs an energizing signal to the solenoid valve power supply circuit 16, and the solenoid valve is immediately turned on. Open 2. In this case, if the time between closing and opening the solenoid valve 2 is short, the gas appliance F in use will not be extinguished by the residual gas in the gas pipe 1, and will continue to burn after the solenoid valve 2 is opened. . On the other hand, if the input voltage from the gas pressure detector 3 does not drop below the memory voltage value of the memory circuit 14 even after a certain period of time has elapsed, this means that the gas is not being used.
2 is automatically turned off.

Furthermore, when the starting switch 12 is turned off (more precisely, when the ON state memory circuit 12a is reset), the comparator circuit 15 outputs the information to the solenoid valve power supply circuit 1.
After that, the input voltage from the gas pressure detector 3 is output to the memory circuit 1 within a certain period of time.
4, the alarm display unit 13 is energized to issue an alarm, and the solenoid valve power supply circuit 16 is electrically locked in the energized cutoff state, and after a certain period of time, the gas pressure detector 3 When the input voltage decreases, the solenoid valve 2 is once opened, the downstream side is set to the supplied gas pressure, and the comparison circuit 15 again compares the input voltage within a certain period of time with the stored value. Thereafter, after the solenoid valve 2 closes, a certain period of time is required for comparing the input voltage from the gas pressure detector 3 with the previous memory value stored in the memory circuit 14.
A relatively long time, such as 20 minutes, is set so that even the slightest gas leak can be detected. Also,
Even after this certain period of time, the gas pressure in the gas pipe 1 may decrease due to the change in the ambient temperature described above. Therefore, if the input voltage from the gas pressure detector 3 decreases after a certain period of time, Once opened, the downstream side is set to the supplied gas pressure, and the comparator circuit 15 again compares the input voltage within a certain period of time with the stored value, and then when it is time to start using the gas, the memory circuit 14 is The stored value corresponds to the supply gas pressure. In addition, solenoid valve power supply circuit 1
6, in order to electrically lock the energization cutoff state, the prohibition circuit 20 is connected to the comparison circuit 15 and the solenoid valve power supply circuit 16.
When a lock signal is sent from the comparison circuit 15 to the prohibition circuit 20, the solenoid valve power supply circuit 16 is electrically cut off until the next reset signal is input to the prohibition circuit 20. A device that locks onto the camera is used.

Furthermore, when the reset switch is turned on, the electrical lock is released and the alarm display section 13 is turned on.
The start switch 12 is then turned off.
When turned on, the solenoid valve power supply circuit 16 opens the solenoid valve 2 for a certain period of time, and the voltage value of the gas pressure detector 3 after a certain period of time after the solenoid valve 2 closes is compared with the value stored in the storage circuit 14 and the comparison circuit 15 When a voltage drop is detected, the alarm display unit 13 is energized again, and the solenoid valve power circuit 16 is electrically locked in the de-energized state. If no voltage drop is detected, the solenoid valve power circuit 16 is energized again. A signal is output to open the solenoid valve 2.

Note that 21 in the figure is a power supply circuit that supplies necessary power to each part. Further, 22 is an external signal output terminal, and a timer 2 for energizing the ventilation fan 23.
4, and when the solenoid valve 2 is energized, the timer 2
4, the ventilation fan 23 is operated intermittently at regular intervals.Furthermore, a signal from a comparator circuit 15 is input to the timer 24, and the amount of gas pressure drop within a certain range due to gas usage is inputted to the timer 24. The operating amount of the ventilation fan 23 is controlled accordingly.

[Effects of the Invention] The gas pipe monitoring device of the present invention is as described above, and when the start switch 12 is turned on at the time of starting gas use, the input voltage from the gas pressure detector 3 at that time is stored in the memory circuit 14. The comparator circuit 15 compares the input signal from the gas pressure detector 3 that was previously installed, and if there is no voltage drop, it is determined that there is no gas leak due to piping failure due to the previous non-use of gas. It is possible to omit the conventional pre-use inspection in which the electromagnetic valve is opened once, supply gas pressure is sent downstream, and the electromagnetic valve is closed to monitor changes in the gas pressure in the pipe over a certain period of time.

Further, in the gas pipe monitoring device of the present invention, when the input voltage from the gas pressure detector 3 is the same as the stored voltage value for a certain period of time, the comparison circuit 15
A signal to cut off the energization is output to close the solenoid valve 2. After that, when the input voltage from the gas pressure detector 3 falls below the memorized voltage value within a certain period of time, the comparator circuit 15 outputs a signal to energize the solenoid valve power supply circuit 16. The solenoid valve 2 is immediately opened, and if the input voltage from the gas pressure detector 3 does not drop below the voltage value stored in the memory circuit 14 even after a certain period of time has elapsed, the start switch 12 is automatically activated.
Since the switch is configured to turn off, the starter switch 12 is checked at regular intervals to ensure that it has not been turned off.
OFF, and the solenoid valve 2 can be kept closed as a general rule with the least risk of danger.

Furthermore, the gas pipe monitoring device of the present invention not only performs the same post-use inspection as the conventional device when the start switch 12 is turned off, but also ensures that the gas leakage during this post-use inspection is so small as to pose no danger. or when the gas pressure in the pipe decreases due to a cause other than gas leakage, the solenoid valve 2 is opened once to send the supply gas pressure to the downstream side, and the next time the gas is used, the pre-use inspection can be omitted. It's becoming like that.
If this transfer is detected when the gas is not in use, the gas cannot be used unless the reset switch 17 is turned on.Furthermore, if the reset switch 17 is turned on, it will be different from when the normal gas use starts. In contrast, the present invention provides a gas pipe monitoring device that performs inspection before use and ensures high stability without any restrictions that require particular effort in gas use.

[Brief explanation of the drawing]

FIG. 1 is a front view of the gas pipe monitoring device of the present invention, and FIG. 2 is a block wiring diagram of a control panel used in the present invention. 1-Gas piping, 2-Solenoid valve, 3-Gas pressure detector, 10-Control panel, 11-Input end, 12-Start switch, 13-Alarm display section, 14-Storage circuit, 1
5 - Comparison circuit, 16 - Solenoid valve power supply circuit, 17 - Reset switch, 18 - Amplification circuit, 19 - A/D conversion circuit, 20 - Inhibition circuit.

Claims (1)

[Claims] 1. A solenoid valve 2 for opening and closing the gas supply to the downstream side of the gas piping 1 is provided at the upstream portion of the gas piping 1, and a voltage value is provided downstream of the solenoid valve 2 to measure changes in the gas pressure in the pipe. The electromagnetic valve 2 includes an input end 11 of the gas pressure detector 3, and a start switch 12 that turns on when gas is used and turns off when gas is used. , a reset switch 17, and an alarm display section 13, and further includes a memory circuit that stores the input voltage from the gas pressure detector 3 at that time each time the solenoid valve 2 is closed when the start switch 12 is turned off. 14, the memory value of this memory circuit 14 and the subsequent gas pressure detector 3
A comparison circuit 15 that compares the voltage value of 12 is turned on, the comparison circuit 15 compares the input voltage from the gas pressure detector 3 at that point with the previous input signal from the gas pressure detector 3 stored in the memory circuit 14. Therefore, the comparison circuit 1 is applied only when there is no voltage drop.
5 outputs an energizing signal to the solenoid valve power supply circuit 16 to open the solenoid valve 2, and also, when the solenoid valve 2 is energized, the gas pressure detector 3
When the input voltage of the solenoid valve 2 decreases by more than a certain percentage than the voltage value stored in the memory circuit 14, the comparator circuit 15 outputs a energization cutoff signal to the solenoid valve power supply circuit 16 to close the solenoid valve 2. If the input voltage from the gas pressure detector 3 is the same as the memorized voltage value for a certain period of time in the energized state, a signal to cut off the energization is output from the comparison circuit 15 to the solenoid valve energizing circuit 16, and the solenoid valve 2 is closed for a certain period of time. When the input voltage from the gas pressure detector 3 drops below the memorized voltage value, the comparator circuit 15 outputs an energizing signal to the solenoid valve power supply circuit 16 to immediately open the solenoid valve 2, and the gas remains open even after a certain period of time has passed. If the input voltage from the pressure detector 3 does not drop below the voltage value stored in the memory circuit 14, the starting switch 12 is automatically turned off. Also, when the starting switch 12 is turned off, the comparator circuit 15 A signal to cut off the energization is output to the solenoid valve power supply circuit 16, and then, when the input voltage from the gas pressure detector 3 falls below the previous stored value stored in the memory circuit 14 within a certain period of time, the alarm display section 13 is energized. In addition to issuing an alarm, the solenoid valve power supply circuit 16
The current is electrically locked in the cut-off state, and when the input voltage from the gas pressure detector 3 decreases after a certain period of time has passed, the solenoid valve 2 is opened once, the downstream side is set to the supply gas pressure, and the comparison is made again. The circuit 15 compares the input voltage within a certain period of time with the stored value, and furthermore, when the reset switch is turned on,
The electrical lock is released and the power to the alarm display section 13 is cut off. Next, when the start switch 12 is turned on, the solenoid valve power supply circuit 16 opens the solenoid valve 2 for a certain period of time. The voltage value of the gas pressure detector 3 after a certain period of time after closing is compared with the value stored in the memory circuit 14 by the comparator circuit 15, and when a voltage drop is detected, the alarm display section 13 is energized again and the solenoid valve power supply circuit 16 is energized. If the state is electrically locked and no voltage drop is observed, a energization signal is output to the solenoid valve power supply circuit 16 again to close the solenoid valve 2.
A gas piping monitoring device formed by connecting a control panel 10 with an open circuit.