JP4288731B2 - Gas shut-off device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas shut-off device that prevents a gas accident in advance.
[0002]
[Prior art]
Conventionally, this type of gas cutoff device will be described with reference to FIG. 1 is a flow rate sensor that outputs a flow rate signal corresponding to the flow rate of the passing gas, 2 is a flow rate measuring unit that measures a passing flow rate from the flow rate signal of the flow rate sensor 1 and outputs a gas flow rate value, and 3 opens and closes the gas passage. A shut-off valve, 4 is a valve drive unit that opens and closes the shut-off valve 3, 5 is a pressure sensor that outputs a pressure signal corresponding to the pressure of the gas passage, and 6 is a seismic signal that responds to shaking in the event of an earthquake. The seismic sensors 700 and 701 output various sensor input units that output sensor values from the signals of the respective sensors, and 110 indicates the pressure because the sensor input unit 700 of the pressure sensor 5 has a large current of several mA. Sensor power on / off unit composed of a resistor and a transistor for turning on / off power only when measuring, 8 is a notification unit composed of LED and LCD, 9 is a communication unit communicating with the center, etc., 14 is a gas shut-off device Power supply Batteries and, 10 is a control unit. When the gas flow rate value from the flow rate measuring unit 2 is an abnormal value such as a gas leak or when the sensor value is abnormal from the various sensor input units 700 and 701 (the pressure is abnormally low or there is an earthquake) In this case, the valve drive unit 4 is driven to operate the shut-off valve 3 to close the gas passage to ensure the safety of the gas, and the content is notified by the notification unit 8, and the communication unit 9 is remotely notified to the center or the like. .
[0003]
[Problems to be solved by the invention]
However, in such a gas shut-off device, the current leakage abnormality of various sensor input sections is not known as described below, so that not only the reliability of the gas shut-off device is lowered, but also the capacity of the battery that is the power source of the entire device In some cases, the service life was less than 10 years. Whether there is a signal from the flow rate measuring unit 2, whether there is a signal from the sensor input unit 701 of the seismic sensor 6, or even if the sensor value of the sensor input unit 701 of the pressure sensor 5 is 0, the signal or value itself In such a configuration, an abnormality such as a leakage current cannot be determined. Furthermore, various sensor input units (flow rate measuring unit 2, sensor input units 700 and 701) have recently been made of semiconductors and are often miniaturized due to the miniaturization of gas cutoff devices. Therefore, there is a high possibility that current leakage due to semiconductor leakage current or dew condensation will occur, and when such leakage current occurs, the current of each sensor input section increases and each sensor input section malfunctions. Although it was not found, there was a case where the power supply was a battery, and the usage period was less than 10 years. Further, as shown in FIG. 8 as an example of a pressure sensor, a sensor input unit is incorporated in the pressure sensor, and there are many cases in which a lead wire is connected therebetween. In such a configuration, the circuit current increases due to short-circuiting or miswiring of the lead wires, and the abnormality cannot be found, and the power source is a battery, so there is a case where there is no use period.
[0004]
Therefore, in the gas shut-off device of the present invention, the leakage current abnormality of each of the flow rate measuring unit and the various sensor input units is individually detected and immediately detected where the abnormality has occurred, so that the gas shut-off device abnormality can be quickly detected. The purpose is not to unnecessarily consume battery capacity.
[0005]
[Means for Solving the Problems]
This gas shut-off device is equipped with an abnormal current detection unit that detects abnormal currents in the power supply line of the flow rate measurement unit and various sensor input units, and controls this signal when there is an abnormal current signal from the abnormal current detection unit. The information is determined by the display unit, the LED or LCD is displayed by the notification unit, or the valve drive unit is driven to operate the valve to shut off the gas passage, and the communication unit notifies the center of the abnormality. As a result, it is possible to notify which sensor's intake part is abnormal, so that it is possible to take quick measures such as replacement of the gas cutoff device and confirmation of connection of the sensor part.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 of the present invention inserts a resistor having a value that hardly causes a voltage drop in a current flowing in a normal state in the power supply lines of the flow rate measuring unit and various sensor input units, and the leakage current is reduced. When there is an abnormal signal from the abnormal current detection unit and the abnormal current detection unit that detects the voltage after the voltage drop of the resistance that occurs when it flows, it is notified by the notification unit or the valve drive unit is driven to shut off the valve A control unit is provided that shuts off the gas passage and notifies the center, etc. via the communication unit. If there is an abnormality such as a leakage current or wiring abnormality, it is detected by the abnormal current detection unit and controlled by the abnormal signal. It has the effect of performing notification or blocking of the gas passage and notification to the center.
[0007]
The invention according to claim 2 detects the voltage drop of the resistance between the emitter and the base of the PNP transistor by inserting the abnormal current detection part of claim 1 into the power supply line of the flow rate measurement part and various sensor input parts. It is composed. When detecting the voltage after a voltage drop due to resistance, even if no abnormal current is flowing, the current increases due to the addition of a detection element to detect the current, placing a burden on the battery as the power supply of the device However, in this configuration, when the abnormal current does not flow, the transistor is not turned on, so that the current for detecting the abnormal current is made almost zero.
[0008]
According to the third aspect of the present invention, when a leakage current flows when a resistor having a value that hardly causes a voltage drop is inserted in a normal current flowing in the power supply line of the flow rate measuring unit and various sensor input units. An abnormal current detection unit that detects the voltage after the voltage drop of the resistance occurs in the sensor, a sensor power on / off unit that controls the power supply on / off of the various flow rate measurement units and various sensor input units, When there is an abnormal signal from the abnormal cancel input unit that gives instructions from the outside to turn on the power of various sensor input units, the abnormal current detection unit of the flow rate measurement unit and various sensor input units, the sensor power on / off unit is driven. Turn off the power of the sensor input unit or flow rate measurement unit that is abnormal and notify it by the notification unit, or drive the valve drive unit to operate the shutoff valve to shut off the gas passage and notify the center etc. via the communication unit Do On the other hand, if there is a signal from the abnormality canceling input unit, a control unit that drives the sensor power on / off unit again to turn on the power is provided, and if there is an abnormality such as leakage current or wiring abnormality, current detection The sensor power supply on / off unit is driven from the control unit by the abnormality signal detected by the control unit, and the sensor input unit or the flow rate measurement unit that detects the abnormality is turned off to notify or block the gas passage and notify the center. After that, in the case of wiring abnormality, the wiring is returned to normal and a signal is input from the abnormality canceling input unit to drive the sensor power on / off unit from the control unit to turn on the power and return to normal as a gas shut-off device. Have.
[0009]
【Example】
Embodiments of the present invention will be described below with reference to FIGS.
[0010]
Example 1
FIG. 1 is a functional block diagram of the first aspect of the present invention. In FIG. 1, 1 is a flow rate sensor that outputs a flow rate signal corresponding to the flow rate of the passing gas, 2 is a flow rate measuring unit that measures a passing flow rate from the flow rate signal of the flow rate sensor 1 and outputs a gas flow rate value, and 3 is a gas passage opening and closing unit. 4 is a valve drive unit that opens and closes the shut-off valve 3, 5 is a pressure sensor that outputs a pressure signal corresponding to the pressure in the gas passage, and 6 is a shock-sensitive device that responds to shaking in the event of an earthquake. The seismic sensors 700 and 701 output various sensor input units for outputting sensor values corresponding to the signals from the respective sensors, and 110 is a pressure because the sensor input unit of the pressure sensor 5 has a large current of several mA. The sensor power on / off section 120, 121, 122 is composed of a resistor and a transistor for turning on / off the power only when measuring the power, and the power supply lines of the various sensor input sections 700, 701 and the flow rate measuring section 2 are normal. Various abnormal current detectors composed of a resistor with a value that causes little voltage drop when a current is flowing and a low voltage detection IC that detects the voltage after the voltage drop of the resistor when an abnormal current flows , 8 is a notification unit configured with an LED and an LCD, 9 is a communication unit that communicates with the center, 14 is a battery as a power source for the gas shut-off device, and 15 is a control unit configured with a microcomputer.
[0011]
The control unit 15 has a conventional function (i.e., when the gas flow rate value entering the INF terminal from the flow rate measurement unit 2 is an abnormal value such as gas leakage, or from various sensor input units entering the IN1 terminal and IN2 terminal. When the sensor value is abnormal, that is, when the pressure is abnormally low or when there is an earthquake, the valve drive unit 4 is driven to operate the shut-off valve 3 to close the gas passage to ensure gas safety. In addition to the function of notifying by the notification unit 8 and remote notification to the sensor or the like by the communication unit 9), when there is an abnormal signal from the various abnormal current detection units 120, 121, 122 to the AC1 terminal and AC2 terminal, the notification unit 8 is It has a function of notifying by driving or driving the valve driving unit 4 to operate the shutoff valve 3 to shut off the gas passage and to notify the center or the like via the communication unit 9.
[0012]
Now, if there is an abnormality such as a leakage current or wiring abnormality in the seismic sensor input unit 701, it is detected by the abnormal current detection circuit 121 and input to the IN2 terminal. This signal is detected by a microcomputer to notify the notification unit 8 that there has been an abnormality in the sensor input unit 701 of the seismic sensor 6, or the valve drive unit 4 is driven to operate the shut-off valve 3 and the gas passage. Shut off and notify the center, etc. via the communication unit 9, and check the wiring status of the seismic sensor according to the contents of the notification, and if it is necessary to replace the gas shut-off device, replace it and take a quick response it can.
[0013]
The above-described control can be easily realized by using a calculation or determination function based on a program operation of the microcomputer. The AC2 terminal and ACF terminal are used as microcomputer interrupt port inputs. FIG. 2 shows a program flow when an abnormal current is detected by various abnormal current detectors.
[0014]
First, a program flow for detecting an abnormal current at the sensor input portion of the pressure sensor 5 will be described. In process 201, it is monitored whether or not the interval timer for inputting the pressure value of the pressure sensor 5 has elapsed, and if a certain period of time has elapsed, the BC1 terminal is turned on in process 202 and the sensor input unit 700 is turned on. To. Next, in step 203, the AC1 terminal is input, and in step 204, it is determined whether or not an abnormal current flows according to the state of the AC1 terminal. If no abnormal current flows, a sensor value is input from the IN1 terminal. If an abnormal current is flowing, it is notified by the notification unit 8 in a process 205 or the valve drive unit 4 is driven to operate the shut-off valve 3 to shut off the gas passage and notify the center or the like via the communication unit 9.
[0015]
Next, a program flow for detecting abnormal currents in the sensor input unit 701 of the seismic sensor 6 and the flow rate measuring unit 2 of the flow rate sensor 1 is shown. When there is an abnormal current signal at the AC2 terminal and the ACF terminal, the AC2 terminal and the ACF terminal are interrupt ports, so the interrupt start is started, and the notification unit 8 notifies in the process 208 or the valve drive unit 4 is driven. Then, the shutoff valve 3 is operated to shut off the gas passage and notify the center or the like via the communication unit 9.
[0016]
(Example 2)
3 and 4 are functional block diagrams of the abnormal current detector according to claim 2. FIG. 3 is a circuit block diagram of the abnormal current detection unit of the sensor input units 700 and 701 of the pressure sensor 5 and the seismic sensor 6. FIG. 4 is a circuit block diagram of the abnormal current detection unit of the flow rate measurement unit 2 of the flow rate sensor 1.
[0017]
In FIG. 3, reference numeral 301 denotes a resistor inserted into the power supply lines of various sensor input units 700 and 701. The resistance value is usually selected so that the Vbe of the PNP transistor 302 does not exceed 0.4 V due to the current flowing through the input units 700 and 701 in various sensors. Reference numeral 302 denotes a PNP transistor in which an emitter and a base are connected to both ends of the resistor 301. When an abnormal current flows through the various sensor input units 700 and 701, when the potential of Vbe of the PNP transistor 302 becomes 0.7V or more, the PNP transistor 302 is turned ON and the resistor 303 connected to the collector of the PNP transistor 302 becomes a voltage of VB. Thus, this voltage is input as an abnormal current signal to the AC1 terminal and AC2 terminal of the microcomputer which is the control unit 15.
[0018]
When the abnormal current does not flow, the PNP transistor 302 is not turned on. Therefore, there is no current flowing to the PNP transistor 302 side other than the current flowing through the sensor input units 700 and 701. As a result, the increase in current when no abnormal current is detected is set to zero, and the battery as a device is not burdened. In FIG. 4, reference numeral 401 denotes a resistor inserted in the power supply line of the flow rate measuring unit 2. This resistance is selected so that the current flowing through the normal flow rate measuring unit 2 is such that Vbe of the PNP transistor 402 does not exceed 0.4V. Reference numeral 402 denotes a PNP transistor having an emitter and a base connected to both ends of the resistor 401.
[0019]
When an abnormal current flows in the flow measurement unit, the potential of Vbe of the PNP transistor 402 becomes 0.7 V or more, the PNP transistor 402 is turned on, and the resistor 403 connected to the collector of the PNP transistor 402 becomes a voltage of VB. Is input as an abnormal current signal to the ACF terminal of the microcomputer as the control unit 15. When the abnormal current cannot flow, the PNP transistor 402 is not turned on, so that there is no current flowing to the PNP transistor 402 side other than the current flowing through the flow rate measuring unit 2. As a result, like the abnormal current detection unit in FIG. 3, the increase in current when no abnormal current is detected is made zero, and the battery as a device is not burdened.
[0020]
(Example 3)
FIG. 5 is a functional block diagram of the invention according to claim 3. In FIG. 5, 1 is a flow rate sensor that outputs a flow rate signal corresponding to the flow rate of the passing gas, 2 is a flow rate measuring unit that measures a passing flow rate from the flow rate signal of the flow rate sensor 1 and outputs a gas flow rate value, and 3 is a gas passage opening and closing unit. 4 is a valve drive unit that opens and closes the shut-off valve 3, 5 is a pressure sensor that outputs a pressure signal corresponding to the pressure in the gas passage, and 6 is a shock-sensitive device that responds to shaking in the event of an earthquake. Seismic sensors 700 and 701 for outputting signals, various sensor input units for outputting values corresponding to the signals from the respective sensors, 110, 111 and 112 for power sources for the various sensor input units 700 and 701 and the flow rate measuring unit 2 Among them, 110 is a sensor power on / off section that turns on / off power only when measuring pressure because the sensor input section of the pressure sensor 5 has a large current of several mA. .
[0021]
When 120, 121, and 122 have normal currents flowing through the power supply lines of the various sensor input units 700 and 701 and the flow rate measurement unit 2, resistance and abnormal current with values that hardly cause a voltage drop flowed. Various abnormal current detection units 17 composed of a low voltage detection IC that sometimes detects a voltage after a voltage drop of the resistor, 17 instructs the various sensor input units 700 and 701 and the flow rate measurement unit 2 to turn on the power again. Anomaly cancellation input unit configured with commands from a switch and a communication unit, 8 is a notification unit configured with an LED and an LCD, 9 is a communication unit that communicates with the center and the like, 14 is a battery as a power source for the gas shut-off device, Reference numeral 16 denotes a control unit composed of a microcomputer.
[0022]
The control unit 16 has a conventional function (i.e., when the gas flow rate value entering the INF terminal from the flow rate measuring unit 2 is an abnormal value such as a gas leak, or from various sensor input units entering the IN1 terminal and IN2 terminal. When the sensor value is abnormal, that is, when the pressure is abnormally low or when there is an earthquake, the valve drive unit 4 is driven to operate the shut-off valve 3 to close the gas passage to ensure the safety of the gas and to inform the contents In addition to the function of notifying in the unit 8 and notifying the sensor etc. remotely in the communication unit 9), if there is a terminal abnormality signal in the AC1 terminal, AC2 terminal, ACF from various abnormal current detection units 120, 121, 122 In order to turn off the power of the flow rate measuring unit 2 or the sensor input unit 700, 701, the sensor power on / off unit is turned off by controlling the BC1 terminal, the BC2 terminal, and the BCF terminal according to the block where the abnormality occurred. Part 8 via the communication unit 9 to drive to shut off the gas passage by operating the shut-off valve 3 to drive the or a valve driving unit 4 notifies centers has a function of notifying. Further, when there is an input from the abnormality cancellation input unit 17, the control unit 16 controls the BC1 terminal, the BC2 terminal, and the BCF terminal to turn on the flow rate measurement unit 2 and the sensor input units 700 and 701 again.
[0023]
Now, if there is an abnormality such as a leakage current or wiring abnormality in the pressure sensor input unit 700, it is detected by the abnormal current detection circuit 120 and input to the IN1 terminal. This signal is detected by a microcomputer and the BC1 terminal is controlled so that the power to the sensor input unit 701 is not turned on to notify the notification unit 8 that there is an abnormality in the sensor input unit 700 of the pressure sensor 5 or The valve drive unit 4 is driven to operate the shut-off valve 3 to shut off the gas passage and notify the center or the like via the communication unit 9 to check the wiring status of the pressure sensor according to the content of the notification or to replace the gas shut-off device If necessary, it can be replaced and a quick response can be taken.
[0024]
At this time, if the pressure sensor has a configuration as shown in FIG. 8 and the leakage current has increased due to a short of the lead wire, the lead wire is corrected and the sensor input is again performed by operating the abnormality canceling input unit 17. The power of the unit 701 can be turned on to recover normally.
[0025]
The above-described control can be easily realized by using a calculation or determination function based on a program operation of the microcomputer. The AC2 terminal and ACF terminal are used as microcomputer interrupt port inputs. In addition, an abnormal flag is provided in the microcomputer to indicate whether or not an abnormality is detected, so that the sensor power supply on / off portion is not turned on during the abnormality. This flag is reset in the initial state. FIG. 6 shows a program flow when an abnormal current is detected by various abnormal current detectors.
[0026]
First, the program flow of the pressure sensor 5 will be described. In process 601, it is monitored whether or not the interval timer for inputting the pressure value of the pressure sensor 5 has elapsed. If a certain period of time has elapsed, the process proceeds to process 602. In step 602, it is determined whether the abnormal flag is set. If not set, the next process 604 is performed. If it is set, the process returns to the standby state without performing the processing from 604 onward. In step 604, the AC1 terminal is input. In step 605, it is determined whether an abnormal current has flown according to the state of the AC1 terminal. If no abnormal current flows, the sensor value from the IN1 terminal is input.
[0027]
If an abnormal current is flowing, an abnormal flag is set in step 606, and a notification unit 8 notifies in step 607 or the valve drive unit 4 is driven to operate the shut-off valve 3 to shut off the gas passage to the center or the like. Notification is made via the communication unit 9. If it is determined in step 601 that the predetermined period has not elapsed, it is determined in step 610 whether there is a cancel input from the error cancel input unit. If there is no cancel input, the process returns to the standby state. If there is a cancel input, the various abnormality flags are reset in processing 611, and if the BC2 terminal and BCF terminal are in the cut state in processing 616, they are turned on. In step 606, the abnormal flag is set, and in step 611, the BC1 terminal is not turned ON until the abnormal flag is reset.
[0028]
Next, a program flow for detecting abnormal currents in the sensor input unit 701 of the seismic sensor 6 and the flow rate measuring unit 2 of the flow rate sensor 1 is shown. If there is an abnormal current signal at the AC2 terminal or ACF terminal, the AC2 terminal and ACF terminal are interrupt ports, so the interrupt start is started, and it is determined in processing 612 whether or not the abnormal flag is set. If yes, the following process 613 is performed. If it is not set, no processing is executed and the process returns from the interrupt. In step 613, the BC2 terminal or BCF terminal is controlled to turn off the flow rate measuring unit 2 or the sensor input unit 701. In step 614, an abnormal flag is set. In step 615, the notification unit 8 notifies or The drive unit 4 is driven to operate the shutoff valve 3 to shut off the gas passage and notify the center or the like via the communication unit 9.
[0029]
In processing 613, an abnormal flag is set, and in step 614, the BC2 terminal and the BCF terminal are turned off. In processing 611, the abnormal flag is reset, and in processing 616, the BC2 terminal and BCF terminal are turned on. Since the sensor input unit 701 of the seismic sensor 6 is not turned on, no interruption occurs. That is, AC2 and ACF interrupt processing is not executed.
[0030]
【The invention's effect】
Each leak current of the gas shut-off device input section (flow rate measurement section and various sensor input sections) is individually detected to immediately detect where an abnormality has occurred and respond quickly to the gas shut-off device abnormality. In addition, it is possible to improve the reliability of the gas shut-off device by not unnecessarily consuming the battery capacity.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a gas shut-off device according to a first embodiment of the present invention. FIG. 2 is a program flowchart of the device.
(b) Program flow chart for detecting an abnormal current of the apparatus. FIG. 3 is a functional block diagram of an abnormal current detecting section of various sensor input sections in Embodiment 2 of the invention. FIG. 4 is an abnormal current of a flow measuring section in the apparatus. FIG. 5 is a functional block diagram of a gas shut-off device in Embodiment 3 of the present invention. FIG. 6 is a program flowchart of the device. FIG. 7 is a functional block diagram of a conventional gas shut-off device. Configuration diagram of pressure sensor with integrated sensor input [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Flow sensor 2 Flow measurement part 3 Shut-off valve 4 Valve drive part 8 Notification part 9 Communication part 14 Battery 15 Control part 120, 121, 122 Various abnormal current detection parts 701, 702 Various sensor input parts

Claims (3)

A flow rate sensor that outputs a flow rate signal corresponding to the flow rate of the passing gas, a flow rate measurement unit that measures a passing flow rate from the flow rate sensor signal and outputs a gas flow rate value, a shut-off valve that opens and closes the gas passage, and opening and closing the shut-off valve A valve drive unit for driving, various sensor input units for inputting signals from various sensors and outputting respective sensor values, an informing unit for informing a shut-off event, a communication unit for communicating to the outside, and the flow rate measurement Various abnormal current detectors that detect abnormal currents of the sensor and various sensor input units and generate abnormal current signals, and when the gas flow rate value from the flow rate measuring unit is abnormal or the sensor values from the various sensor input units In the case of abnormality, the valve drive unit is driven to operate the shut-off valve to close the gas passage, and when there is an abnormal current signal from the various abnormal current detection units, the notification unit is notified or the valve drive is performed. Gas cutoff device including a control unit for notifying to the outside, a battery as a power source of the apparatus by the communication unit is driven to close the gas passage by operating the shutoff valve. The gas cutoff device according to claim 1, wherein the various abnormal current detectors detect a voltage drop of a resistance provided on a power supply line of the flow rate measuring unit and each sensor input unit between the emitter and base of the transistor. A flow rate sensor that outputs a flow rate signal corresponding to the flow rate of the passing gas, a flow rate measurement unit that measures a passing flow rate from the flow rate sensor signal and outputs a gas flow rate value, a shut-off valve that opens and closes the gas passage, and opening and closing the shut-off valve A valve drive unit for driving, various sensor input units for inputting signals from various sensors and outputting respective sensor values, an informing unit for informing a shut-off event, a communication unit for communicating to the outside, and the flow rate measurement Various abnormal current detection units that detect abnormal currents of the sensor and various sensor input units and generate abnormal current signals, and various sensor power on / off units that turn on and off the respective flow rate measurement units and various sensor input units Unit, an abnormality canceling input unit that gives an instruction to turn on the power again to the various sensor input units, and when the gas flow rate value from the flow rate measuring unit is abnormal or the sensor value from the various sensor input units is abnormal When the valve drive unit is driven to operate the shut-off valve to close the gas passage, and when there is an abnormal current signal from the various abnormal current detection units, the various sensor power on / off units are driven to output abnormal currents. Turn off the power of the flow rate measuring unit or the various sensor input units with a signal, notify the notification unit or drive the valve drive unit to operate the shut-off valve, close the gas passage, and notify the outside by the communication unit On the other hand, when there is a signal from the abnormality canceling input unit, the control unit for driving the various sensor power on / off unit and turning on the flow rate measuring unit or the various sensor input unit having an abnormal current signal again, Gas shut-off device equipped with a battery as a power source for the device.

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