JPH11141870A - Gas shutoff device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the opened- and closed-state of a shutoff valve by means of one kind of control section even when the shutoff valve is manufactured for different specifications or by a different manufacture. SOLUTION: First and second limit driving circuits 7 and 11 which are respectively adapted to the electrical characteristics of cutoff values 1a and 1b which are assumed to be used as a shutoff valve 1 are provided ant the limit driving circuit which is used for the actual shutoff valve 1 is stored in advance in a storing means 22. When a control section 23 detects the opened- and closed- state of the valve 1, the section 23 impresses a voltage upon the valve 1 by operating the adaptive limit control circuit stored in the storing means 22 and a transient response detecting section 15 detects the state of the transient response of the valve 1 and detects the opened- and closed-state of the valve based on the detected results. Since the resistance values of first and second limiting resistors 8 and 12 are set so that the same transient response may be outputted correspondingly to the electrical characteristics of the shutoff valves 1a and 1b, the control section 23 can discriminate on the same basis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shut-off device for preventing a gas accident from occurring.

[0002]

2. Description of the Related Art Various types of safety devices have been used to prevent a gas accident that is likely to be a catastrophe once it occurs. When the flow rate is monitored and the microcomputer determines that the gas usage status is abnormal, or when the status of sensors such as earthquake sensors, gas pressure sensors, and gas alarms is monitored and the status is determined to be dangerous. A gas meter (hereinafter, referred to as a microcomputer meter) having a built-in gas shut-off device equipped with a microcomputer using a battery power supply that shuts off gas by a shut-off valve built in the gas meter has a high safety and ease of gas piping. It has been promoted because of its advantages such as low price, and in recent years, it has been spread to all households. In addition, the ratio of centralized monitoring type microcomputer meters equipped with a telemeter function that centrally monitors the gas flow rate information measured by the flow rate sensor using a telephone line etc. has also increased, improving the convenience of information terminals. It has been demanded.

[0003] As a shut-off valve of this gas shut-off device, in order to suppress the power consumption of the battery, current flows only at the time of shut-off operation or return operation, and in other cases, the balance between the attractive force of the permanent magnet and the reaction force of the spring. A self-holding type solenoid valve that holds an open state or a closed state is generally used as a shutoff valve. However, there is a possibility that this shut-off valve malfunctions such that the opening / closing state changes when an impact or the like is applied. Therefore, a gas shut-off device having a means for detecting the open / closed state of the shut-off valve is required in order to check the operation of the shut-off valve, detect a state change due to an impact or the like, and report or correct a malfunction.

Hereinafter, a conventional gas shut-off device will be described. Japanese Patent Application Laid-Open No. 7-55052 discloses a gas shut-off device provided with means for detecting the open / close state of the shut-off valve as described above. FIG. 8 is a circuit diagram showing the configuration of the gas shut-off device. In FIG. 8, reference numeral 101 denotes a shut-off valve for shutting off a gas passage, which includes an equivalent resistor 102 and an equivalent inductance 103; 104, a drive circuit including a transistor 105 and a resistor 106 for driving the shut-off valve 101 to open and close;
107 is a limiting resistor 108, a transistor 109 and a resistor 1
10 and the shut-off valve 1 through the limiting resistor 108.
01 is a limiting drive circuit that applies a voltage to 01, 111 is a resistor 11
A transient response detector configured to include a transient response of the shut-off valve 101 when the limiting drive circuit 107 is operated, and detect and output a transient response situation; Reference numeral 116 denotes a flow rate measuring means for measuring the passing gas flow rate, and 117 detects the abnormal flow rate pattern by the flow rate measuring means 116 to drive the drive circuit 104 to close the shutoff valve 101 and to operate the limit drive circuit 107. A control unit for detecting the open / closed state of the shut-off valve 101 based on the state of the transient response detected by the transient response detection unit 111; a display unit 118 for displaying the control state; and a battery 119 as a power supply.

In the shut-off valve 101, the equivalent resistance 102 is the equivalent resistance of the electromagnetic coil, and the equivalent inductance 10
3 is the equivalent inductance of the electromagnetic coil. The value of the equivalent inductance 103 differs depending on the open / closed state of the shut-off valve 101. When the value in the open state is L1 and the value in the closed state is L2, L1> L2. In the transient response detection unit 111, the resistance 112 and the resistance 113 set the reference potential of the comparator 115, and the resistance 114
Pulls up the output of the comparator 115. The limiting drive circuit 107 is a means for applying a voltage to the shut-off valve 101 via the limiting resistor 108 to output a transient response, and does not open or close the shut-off valve 101 because the current is small.

The operation of the gas shut-off device having the above configuration will be described. FIG. 9 is a characteristic diagram illustrating a transient response input to the transient response detection unit 111 when the limiting drive circuit 107 is operated. When the limiting drive circuit 107 is operated immediately after opening / closing the shutoff valve 101 or the like, the transient response input to the comparator 115 of the transient response detection unit 111 is based on the shutoff valve 1
Since there is a difference in the value of the equivalent inductance 103 in the open / close state of 01, the waveform corresponds to the open / close state of the shut-off valve 101, as shown in FIG. Assuming that the reference potential of the comparator 115 is Vref, the time when the potential of the transient response input to the comparator 115 becomes lower than the reference potential Vref from the start of operation of the limiting drive circuit 107 is referred to as the shut-off valve 101.
If T1 is in the closed state and T2 is in the open state, the shut-off valve 1
01 is equal to L1>
Since L2, T1> T2.

A timer is incorporated in the control unit 117, and a determination time T3 substantially intermediate between T1 and T2 is set in a program of the timer written in a ROM (read-only storage device). The output potential of the comparator 115 at the time when the determination time T3 has elapsed since the drive circuit 107 started operating is taken in. When the output potential is H (high potential), it is determined that the shut-off valve 101 is closed, and L ( (Low potential), it is determined that the shutoff valve 101 is in the open state.

[0008]

In such a gas shut-off device, it is required that the open / close state of the shut-off valve 101 can be reliably detected. On the other hand, since the shut-off valve 101 is designed with an emphasis on opening and closing reliably with power saving, it is difficult to design the value of the equivalent inductance 103 in the open / closed state to a predetermined value. Therefore, when the design is modified or the manufacturer is different, the value of the equivalent inductance 103 is not unified and generally becomes many. In this case, in the above-described conventional configuration, since the predetermined determination time T3 is set in the ROM of the control unit 117 by the burning means, the design of the shut-off valve 101 is changed, or when the shut-off valve of a different maker is used together. The control unit 117 may erroneously detect the open / closed state. For this reason, when using shut-off valves of different specifications and manufacturers, it is necessary to prepare a control unit for each specification and manufacturer with a suitable judgment time set for each. There is a problem that the burden on the user increases.

The present invention solves the above-mentioned problems, and provides a gas shut-off device that can reliably detect the open / close state of the shut-off valve with one type of control unit even when shut-off valves of different specifications and manufacturers are used together. The purpose is to:

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a flow rate measuring means for measuring a flow rate of a passing gas, a shutoff valve for shutting off a gas passage, and a drive for opening and closing the shutoff valve. A voltage is applied to the shut-off valve via a limiting resistor set corresponding to the circuit and the shut-off valve which is assumed to be used as the shut-off valve, and adapted to the corresponding shut-off valve without opening and closing operation. A plurality of limited drive circuits, storage means for storing in advance which one of the plurality of limited drive circuits is a limited drive circuit that is compatible with an actually used shut-off valve, and operating the limited drive circuit. The transient response of the shut-off valve at the time of input, a transient response detection unit that detects and outputs the state of the transient response, a control unit that controls the overall operation, and a battery as a power supply, the control The part is the flow rate measurement When an abnormal flow pattern is detected by the stage, the shutoff valve is closed by the drive circuit, and, if necessary, a suitable limit drive circuit stored in the storage means is operated, and the transient response detection unit This is a gas shut-off device that detects the open / closed state of the shut-off valve based on the state of the detected transient response.

According to the present invention, even when a shut-off valve of a different specification or a different manufacturer is used, a plurality of limited drive circuits can be used.
Select a limiting drive circuit having a limiting resistor suitable for the electrical characteristics of the actually used shut-off valve by designating the storage means,
The transient response detector detects the transient response when the limiting drive circuit is operated, and based on the result, detects whether the shut-off valve is open or closed. Can be provided.

[0012]

According to the present invention, there is provided a flow rate measuring means for measuring a flow rate of a passing gas, a shutoff valve for shutting off a gas passage, a drive circuit for opening and closing the shutoff valve, and the shutoff valve. A plurality of limiting drive circuits provided corresponding to each of the shut-off valves supposed to be used and applying a voltage to the shut-off valve via a limiting resistor set in conformity with the corresponding shut-off valve without opening / closing operation. Storage means for preliminarily storing which of the plurality of limited drive circuits is the limited drive circuit that is compatible with the actually used shutoff valve; and the shutoff valve when the limited drive circuit is operated. A transient response detection unit for inputting the transient response of the transient response, detecting and outputting the state of the transient response, a control unit for controlling the overall operation, and a battery as a power supply, wherein the control unit is configured to measure the flow rate. Abnormal flow by means When a pattern is detected, the drive circuit closes the shut-off valve, and, if necessary, activates a suitable limiting drive circuit stored in the storage means, thereby detecting the transient response detected by the transient response detector. The gas shut-off device is configured to detect an open / close state of the shut-off valve based on a situation.

In the present invention, each of the limiting drive circuits is means for applying a voltage to the shut-off valve via the limiting resistor without opening / closing operation.
It has a limiting resistor with a resistance value that matches the electrical characteristics of the corresponding shut-off valve, and when operated in combination with the corresponding shut-off valve, the same transient response is output from the shut-off valve. Therefore, the open / closed state of the shut-off valve can be detected by one type of control unit.

The storage means is a means for storing which of the plurality of limiting drive circuits is to be used. The storing means is realized by a RAM or the like, and indicates which limit drive circuit is suitable for the actually used shut-off valve. Remember. This memory input can be input in advance through an input means by a human action, or, as in the present invention according to claim 2, can be input to the limited drive circuit specified by learning by the limited drive circuit selecting means.

The transient response detecting section is means for detecting the state of the transient response of the shutoff valve. In the embodiment, the transient response potential of the shutoff valve when the limiting drive circuit is operated is compared with a predetermined reference potential. Then, a means for outputting whether the potential of the transient response is higher or lower than the reference potential with the passage of time. This output is obtained by detecting a temporal change in the potential of the transient response as a state of the transient response. Note that this transient response detection unit can be composed of a reference potential generated by resistance division and a comparator,
An H level or L level signal is output from the comparison result.
Further, the comparison result is inverted depending on whether the reference potential is set to the positive input terminal or the negative input terminal of the comparator. In the embodiment, the positive input terminal is used as the reference potential, but the present invention is not limited to this.

The control unit is constituted by a microcomputer or the like and controls the entire operation. Particularly, when the flow rate of the passing gas has an abnormal flow pattern, the control unit operates to close the shut-off valve to ensure safety. In order to confirm the operation of the shut-off valve, the limiting drive circuit adapted to the shut-off valve is operated, and the open / close state is determined based on the transient response state of the shut-off valve detected by the transient response detecting unit.
In this case, detection is performed by determining whether the output of the transient response detector at the time when a predetermined determination time has elapsed since the start of operation of the limited drive circuit is at the H level or the L level. The fact that the transient response differs between the open state and the closed state of the valve is used.

By the above operations, the same transient response is output even when the judgment time is fixed and the shut-off valves of different specifications and manufacturers are used together. Can be detected.

According to a second aspect of the present invention, the control unit includes a limited drive circuit selecting unit, and the limited drive circuit selecting unit shuts off based on a transient response situation when individually operating the limited drive circuits. 2. A limiting drive circuit suitable for a shut-off valve is detected by detecting an open / closed state of a valve and comparing the detected result with an actual open / closed state as a determination, and outputs the limited drive circuit to a storage means to store it in advance. It is a gas shut-off device related to.

In the present invention, the limited drive circuit selecting means selects, by learning, which of the plurality of limited drive circuits is the limited drive circuit to be used for the actually used shut-off valve, and stores it. This is means to be stored in the means, and is realized by, for example, a learning procedure program stored in the microcomputer. The basics of this learning procedure are as follows: the shutoff valve is forcibly set to the open state or the closed state via the control unit, a plurality of limit drive circuits are sequentially operated under the state, and the transient response detection unit outputs This is a process of selecting a limited drive circuit in which the open / closed state determined by the control unit based on the state of the transient response to be performed matches the open / closed state of the shutoff valve previously set. Note that the detection result of the control unit in this process is treated as a determination.

According to the above-mentioned operation, when the shut-off valves of different specifications or manufacturers are used together, it is not necessary to write in advance in the storage means which of the limiting drive circuits to be used by active means such as dip switches and communication. The open / closed state of the shutoff valve can be reliably detected by one type of control unit using the limited drive circuit.

According to a third aspect of the present invention, the control section has one determination time for referring to a state of the transient response detected by the transient response detection section, and the determination time is determined after the limited drive circuit is operated. 3. The gas shut-off device according to claim 1, wherein a state of a transient response at a time point when a predetermined time has elapsed is inputted to detect an open / close state of the shut-off valve.

In the present invention, the control unit has a built-in timer. For example, one determination time is set in a program of the timer. As described in the first aspect of the present invention, the H level or the L level output as the state of the transient response by the transient response detecting unit at the point in time after the determination time has elapsed.
The open / closed state of the shut-off valve is detected by referring to the level signal.

According to a fourth aspect of the present invention, the control unit includes a first determination time for referring to a state of the transient response detected by the transient response detection unit and a second determination time longer than the first determination time. Detecting the open / closed state of the shut-off valve based on the transient response status at the time when the first determination time has elapsed after operating the limited drive circuit, and detecting the transient response status at the time when the second determination time has elapsed. 3. The gas shut-off device according to claim 1, wherein the detection result is confirmed based on the following.

In the present invention, the control unit includes a timer built therein, and for example, two determination times are set in a program of the timer. Using the two determination times, the open / closed state can be detected while the shut-off valve is kept open. Originally, the potential of the transient response has a characteristic that attenuates and changes with the lapse of time. When one limiting drive circuit is operated, the determination of the detection result at the first determination time and the detection result at the second determination time If the determination is the same, the fact that the response can be determined to be abnormal is used. In this case, the second determination time is set to be considerably longer than the first determination time. For example, if a second determination time is set such that the state determined to be open in the first determination time is determined to be closed in the second determination time, the second determination time considering the characteristics of the transient response is set. The determination time is set to 2, and the condition of the transient response that matches this may be normal, and the determination at the first determination time is correct. Otherwise, it may be in an abnormal state. In such a determination method, it is not necessary to forcibly switch the state of the shut-off valve, and it is not necessary to operate the same limited drive circuit again.

With the above operation, the number of times of driving the drive circuit and the limited drive circuit can be reduced, and confusion and power consumption due to opening and closing of the gas passage can be suppressed.

Hereinafter, specific embodiments of the present invention will be described.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) Hereinafter, Embodiment 1 of a gas shut-off device of the present invention will be described with reference to the drawings. This embodiment relates to claims 1 and 3.

FIG. 1 is a circuit diagram showing the configuration of this embodiment. In the figure, reference numeral 1 denotes a shut-off valve. When two types of shut-off valves having different specifications or different manufacturers are used together, one is a 1a,
The other is 1b. 2 is the equivalent resistance of the electromagnetic coil in the shut-off valve 1, 3 is the equivalent inductance of the electromagnetic coil,
Reference numeral 4 denotes a drive circuit that includes a transistor 5 and a resistor 6 to open and close the shut-off valve 1. Reference numeral 7 denotes a drive circuit that includes a first limiting resistor 8, a transistor 9, and a resistor 10, via the first limiting resistor 8. A first limiting drive circuit for applying a voltage to the shutoff valve 1,
11 is a second limiting resistor 12, a transistor 13 and a resistor 1
And the shut-off valve 1 via the second limiting resistor 12.
A second limiting drive circuit for applying a voltage to
6, a resistor 17, a resistor 18, a resistor 19, and a comparator 20, and the shut-off valve 1 when a voltage is applied to the shut-off valve 1 by either the first limiting drive circuit 7 or the second limiting drive circuit 11. The transient response detector 21 inputs the potential of the transient response of the above, compares it with a predetermined reference potential, and outputs the result, and 21 is a flow rate measuring means for measuring the passing gas flow rate.

Reference numeral 22 denotes a first limiting drive circuit 7 and a second
Storage means 23, such as a RAM (random access memory) for storing which one of the limited drive circuits 11 is to be used, and a drive circuit 23 when the flow rate signal of the flow rate measurement means 21 is an abnormal flow rate pattern. 4 to shut off the gas passage with the shut-off valve 1 and to store the first state stored in the storage means 22 in order to detect the open / close state of the shut-off valve 1.
A control unit that operates either the limited drive circuit 7 or the second limited drive circuit 11 to detect the open / close state of the shut-off valve 1 based on the output of the transient response detection unit 15.
3 is a notifying means for notifying the open / closed state or abnormal state of the shutoff valve 1 to the outside, and 25 is a first limiting drive circuit 7 or a second limiting drive circuit.
Is input means mainly for communication or the like for writing information on which of the limited drive circuits 11 to use in the storage means 22 via the control unit 23, and 26 is a battery as a power supply for the entire gas shut-off device.

In the above configuration, the shut-off valve 1 and the drive circuit 4 are replaced with the shut-off valve 101 and the drive circuit 10 in the conventional example.
4 is substantially the same. The first and second limiting drive circuits 7 and 11 have the same configuration as the configuration of the limiting drive circuit 107 in the conventional example, but the first and second limiting resistors 8 and 12 Suitable values of resistance mainly corresponding to the equivalent inductance 3 of the two types of shutoff valves 1 assumed in advance are set. In the transient response detecting section 15, the resistors 16 and 17 generate the reference potential of the comparator 20 when the first limited drive circuit 7 is operated, and the resistors 16 and 18 are connected to the second limited drive circuit. When the circuit 11 is operated, a reference potential of the comparator 20 is generated.

FIG. 2 is a sectional view showing a schematic configuration of the shut-off valve 1 in the present embodiment. FIG. 2A shows the open state of the shut-off valve 1, and FIG. 2B shows the closed state of the shut-off valve 1. In FIG. 2, a magnetic circuit is formed by a permanent magnet 27, a yoke 28, and a movable iron core 29, and an electromagnetic coil 30 capable of exciting this magnetic circuit, and a valve element 31 disposed at one end of the movable iron core 29. ,
The shut-off valve 1 is constituted by a spring 32 for urging the valve element 31 in the valve closing direction. As shown in FIG. 2, since the position of the movable iron core 29 is different between the open state and the closed state, the value of the equivalent inductance 3 is different. If the value of the equivalent inductance 3 in the open state is L1 and the value in the closed state is L2, then L1> L2.

The operation of the gas shut-off device having the above configuration will be described. Now, it is assumed that the shutoff valve 1 is one of two types of shutoff valves 1a used together. In the normal state, the shut-off valve 1a is opened as shown in FIG. 2 (a) with the movable iron core 29 inserted into the electromagnetic coil 30, and the movable iron core 29 is in a permanent state. The gas is held by being attracted to the magnet 27, and as a result, the gas passage is opened and the gas can be used. On the other hand, the control unit 2
3 detects the abnormal flow pattern by the flow measuring means 21 and drives the drive circuit 4 to drive the electromagnetic coil 3 of the shut-off valve 1a.
0 is excited, and the movable iron core 29 is urged by the spring 32 to protrude from the electromagnetic coil 30 to be brought into the closed state shown in FIG.

FIG. 3 is a characteristic diagram showing a transient response inputted to the transient response detecting section 15. FIG. 3A shows a transient response when the first limiting drive circuit 7 is operated, and FIG. () Shows a transient response when the second limiting drive circuit 11 is operated.

When the first limiting drive circuit 7 is operated, the transient response inputted to the comparator 20 of the transient response detector 15 has a difference of L1> L2 in the value of the equivalent inductance 3 depending on the open / close state of the shut-off valve 1a. Therefore, as shown in FIG. 3A, a transient response corresponding to the open / closed state of the shutoff valve 1a is obtained. Now, the value of the first limiting resistor 8 is R1, the shut-off valve 1a
When the value of the equivalent resistance 2 is r, the value of the equivalent inductance 3 is L, and the voltage of the battery 26 is E, ignoring Vccsat of the transistor 9, the potential V of the transient response of the shut-off valve 1a is obtained.
0 is the resistance R1, the resistance r, and the equivalent inductance L
From the transient response

[0035]

(Equation 1)

Is given by Assuming that the reference potential of the comparator 20 is Vref, the time from when the first limiting drive circuit 7 starts operating until the potential of the transient response input to the comparator 20 of the transient response detection unit 15 becomes lower than the reference potential Vref is determined. T1 when the shut-off valve 1 is open and T when the shut-off valve 1 is closed.
Assuming that 2, the value of the equivalent inductance 3 of the shut-off valve 1a is L1> L2 as described above, so that T1> T2. The control unit 23 has a timer therein, and a determination time T3, which is approximately intermediate between T1 and T2, is previously set in a program or the like burned into the ROM.
Judgment time T3 since the first limiting drive circuit 7 started operating
, The output potential of the comparator 20 at the time of elapse is taken, and when the output potential is H (high potential), the shutoff valve 1a is determined to be closed, and when it is L (low potential), the shutoff valve 1a is determined to be open. .

On the other hand, in the second limiting drive circuit 11,
The value of the second limiting resistor 12 is the value of the other shut-off valve 1 assumed.
b, the transient response input to the comparator 20 of the transient response detector 15 is set to be substantially the same as the transient response when the shut-off valve 1a and the first limiting drive circuit 7 are combined. When the second limiting drive circuit 11 is driven, the time from when the second limiting drive circuit 11 starts operating until the potential of the transient response input to the comparator 20 becomes lower than the reference potential Vref of the comparator 20 is determined by the shut-off valve. 1b is T4 in the open state, T5 in the closed state,
As shown in FIG. 3B, T4ＴT1 and T5, respectively.
≒ T2. Therefore, it is possible to detect the open / closed state of the shut-off valve 1b in the same determination time T3 as the determination time T3 of the first limiting drive circuit 7.

The assembly maker or the manager of the gas shut-off device determines which of the first limit drive circuit 7 and the second limit drive circuit 11 depends on which one of the shut-off valve 1a and the shut-off valve 1b to be used together is actually used. It is determined whether or not to use the information. The information is externally input to the input means 25 by a telegram of the setting device or the like, and is stored in the RAM of the storage means 22 via the control unit 23 and the second limited drive circuit 7 and the second limited drive. Information on which of the circuits 11 to use is written.

When it is necessary to detect the open / closed state of the shut-off valve 1 immediately after the shut-off valve 1 is opened or closed, or when detection information such as impact is obtained, the control unit 23 refers to the information in the storage unit 22. The first limit drive circuit 7 or the second limit drive circuit 11 is operated, the transient response detector 15 detects the status of the transient response, and based on the result, detects the open / closed state of the shut-off valve 1 and informs the user. 24.

As described above, according to the gas shut-off device of this embodiment, the shut-off valves 1a and 1b of different specifications and manufacturers are different.
When the first and second limiting drive circuits 7 and 11 each having a limiting resistor having a resistance value suitable for each characteristic are prepared, the specifications of the shutoff valve 1 actually used and Information as to which one of the first limited drive circuit 7 and the second limited drive circuit is to be used according to the maker is stored in advance in the storage means 22 by means of an electric signal.
In order to detect the state of the transient response by the transient response detector 15 and to detect the open / closed state of the shut-off valve 1 based on the result, the shut-off valve of a different specification or manufacturer is operated. Is used together, the open / closed state of the shutoff valve 1 can be reliably detected by one type of control unit 23.

In this embodiment, the case where two types of shut-off valves are used in combination has been described. However, even in the case where more types of shut-off valves are used in combination, it is possible to cope with them by preparing a limiting drive circuit suitable for each type. It goes without saying that you can do it. Further, although the configuration in which the drive circuit 4 can perform only the shutoff operation has been described, a configuration in which the drive circuit 4 can be energized in both forward and reverse directions to enable shutoff and return may be employed. The comparator 20
Has been described in which the first reference drive circuit 7 and the second limit drive circuit 11 have the same reference potential.
A different reference potential may be used by setting the value of the resistor 17 and the value of the resistor 18 to different values. In addition, although the storage unit 22 has been described as an example configured by a RAM rewritable by information from the input unit 25, it is needless to say that the storage unit 22 may be configured by a switchable dip switch.

(Embodiment 2) Hereinafter, Embodiment 2 of the gas shut-off device of the present invention will be described with reference to the drawings. This embodiment relates to claim 2.

FIG. 4 is a circuit diagram showing the configuration of this embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The present embodiment is different from the first embodiment in that the control unit 23 includes a limited drive circuit selecting unit 33, and detects the state of the transient response using the first limited drive circuit 7 and the second limited drive circuit 11. Then, the state of the shutoff valve detected based on the result is compared with the actual state to determine which of the first limited drive circuit 7 and the second limited drive circuit 11 is to be used, and the storage means 22 and stored in advance, and the limited drive circuit is used in the subsequent detection processing. Therefore, the limiting drive circuit selecting means 33 is operated before the gas shut-off device is actually operated, and the suitable limiting drive circuit is stored in the storage means 22.

As in the first embodiment, the determination time T3 is set in the timer of the control unit 23, and the output potential of the comparator 20 at the time when the determination time T3 has elapsed since the first limiting drive circuit 7 started operating. When the output potential is H (high potential), the shutoff valve 1 is determined to be closed, and when the output potential is L (low potential), the shutoff valve 1 is determined to be open. The same applies to the second limiting drive circuit 11. Now, it is assumed that there is a possibility that both the shutoff valve 1a having a high equivalent inductance and the shutoff valve 1b having a low equivalent inductance may be used together as the shutoff valve 1, and the first limiting resistor 8 in the first limiting drive circuit 7 is used.
Is set so that the open / closed state of the shutoff valve 1a can be determined, and the closed state of the shutoff valve 1b is determined regardless of the open / closed state. The second limiting resistor 12 in the second limiting drive circuit 11 Is set so that the open / close state of the shutoff valve 1b can be determined, and the open state of the shutoff valve 1a is determined regardless of the open / closed state. FIG. 5 is a characteristic diagram showing a transient response corresponding to the above setting. In addition,
The limited drive circuit selecting means 33 is constituted by a program written in the ROM.

The operation of the gas shut-off device having the above configuration will be described with reference to the drawings. FIG. 6 is a flowchart showing the operation of this embodiment.

When the gas meter equipped with the gas shut-off device is started to be used, upon receiving a learning start command by a trigger such as a return signal or a telegram communication with the outside, the limited drive circuit selecting means 33 is activated and the learning process is started. You. First, in step 1, the shut-off valve 1 is returned to the open state by the drive circuit 4. Next, in step 2, the first limiting drive circuit 7 is activated, and in step 3, the transient response detection unit 1
Reference numeral 5 compares the potential of the transient response caused by the first limiting resistor 8 with the reference potential Vref, and outputs an H or L potential corresponding to the result. Next, in step 4, it is checked whether the output potential of the transient response detector 15 is H or L. If H, the shutoff valve 1 is closed, and if L, the shutoff valve 1 is open. Is determined.

When it is determined in step 4 that the shut-off valve 1 is closed, the shut-off valve 1 is returned to the open state, so that the determination of the closed state is false, and the first limiting drive circuit 7 is not appropriate. Therefore, the process proceeds to step 5 and the shutoff valve 1
b, the process proceeds to step 6, and the storage unit 22
To use the second limited drive circuit 11. If it is determined in step 4 that the valve is in the open state, the process proceeds to step 7 and the drive circuit 4 shuts off the shutoff valve 1 to switch to the closed state. Next, in step 8, the first limiting drive circuit 7 is driven again. In step 9, the transient response detecting section 15 compares the potential of the transient response by the first limiting resistor 8 with the reference potential Vref, and corresponds to the result. An H or L potential is output. Next, proceeding to step 10, the control unit 23 checks whether the output potential is H or L, and when the output potential is H, the shutoff valve 1 is in the closed state.
If L, the shutoff valve 1 is determined to be in the open state.

If it is determined in step 10 that the shut-off valve 1 is closed, it is true that the closed state is determined, and the first limiting drive circuit 7 is appropriate. It is determined that the valve is the shut-off valve 1a, and in step 12, the use of the first limiting drive circuit 7 is stored in the storage means 22. If it is determined in step 10 that the output is in the open state, the output potential of the transient response
Is determined to be an unconnected state due to a connection error of the shut-off valve 1 or an abnormal state in which the shut-off valve 1 does not perform the shut-off operation in Step 13, and the limited drive circuit selection is not completed, that is, finish. Note that the other operations are the same as those in the first embodiment, and a description thereof will not be repeated.

As described above, the gas shut-off device of this embodiment is
When the shut-off valves that are assumed to be used are the shut-off valve 1a and the shut-off valve 1b, the control unit 23 receives the return signal at the start of use and a learning start instruction by a trigger such as communication and communicates with the drive circuit 4 and the first restriction The drive circuit 7 is operated, the state of the shutoff valve 1 at that time is compared with the determination result, and if they do not match, the other second limited drive circuit 11 is determined to be appropriate and selected,
Further, when the conditions match, the state of the shut-off valve 1 is changed and the first limiting drive circuit 7 is operated again, and the determination result is compared with the state of the shut-off valve 1. 7
Is determined to be appropriate, and if they do not match, it is determined that the limiting drive circuit is suitable by learning a connection error or an abnormal operation of the shutoff valve 1 and storing the storage means 22.
When the shut-off valve 1a and the cut-off valve 1b of different specifications or manufacturers are used together by detecting an abnormal state, the first limit drive circuit 7 and the second limit drive circuit 11 are used.
The limit drive circuit selecting means 33 learns and writes which of the two is not to be written into the storage means 22 by an active means such as a dip switch or communication. The state can be reliably detected.

In this embodiment, the process of learning the suitability by using only the first limiting drive circuit 7 when there are two types of shut-off valves 1 has been described. You may learn using.

The basis of the learning process in this embodiment is to select a limited drive circuit in which the actual opening / closing state of the shut-off valve 1 matches the result of determination using one determination time T3, and does not match any of them. In this case, it is basically determined to be an abnormal state, and a plurality of limited drive circuits can be sequentially operated to select and store a matching one and detect an abnormal state. It goes without saying that the processing is not limited.

(Embodiment 3) Hereinafter, a third embodiment of the gas shut-off device of the present invention will be described with reference to the drawings. This embodiment relates to claims 2 and 4.

The configuration of this embodiment is almost the same as the configuration of the second embodiment shown in FIG. This embodiment is different from the second embodiment in that a timer in the control unit 23 has two short and long determination times,
That is, the second determination time T6 is set with respect to the determination time T3, the determination using these two determination times is performed together, and the operation of the limited drive circuit selection means 33 is performed.
Here, the determination time T3 is the determination time T3 in the second embodiment.
And the same time. When the second limiting drive circuit 11 having a low limiting resistance is operated, the potential of the transient response in the open state of the shut-off valve 1a having a large equivalent inductance 3 is equal to the reference potential Vref. It is set longer than the lowering time. T6 shown in FIG.
Is the second determination time T6. Note that the control unit and the limited drive circuit selecting unit in this embodiment are slightly different from those in the second embodiment, but the control unit
3. A description will be given of the limited drive circuit selection means 33.

The operation of the gas shut-off device having the above configuration will be described with reference to the drawings. FIG. 7 is a flowchart showing the operation of this embodiment.

First, in response to a return signal for starting use of a gas meter equipped with a gas shutoff device or a learning start command by a trigger such as a message communication with the outside, the limited drive circuit selecting means 33 is activated, and the learning process is started. Is started. First, in step 1, the drive circuit 4 returns the shut-off valve 1 to an open state. Next, in step 2, the first
Is driven by the transient response detection unit 15 in step 3 and the first
Is compared with a reference potential Vref, and an H or L potential corresponding to the determination result is output. Next, in step 4, it is checked whether the output potential of the transient response detector 15 is H or L. If the output potential is H, the shutoff valve 1 is closed, and if L, the shutoff valve 1 is open. Is determined.

If it is determined in step 4 that the shut-off valve 1 is in the closed state, the shut-off valve 1 is returned to the open state, so that the determination of the closed state is false, and the first limiting drive circuit 7 is not appropriate. Then, proceeding to step 5, it is determined that the shut-off valve 1 is the shut-off valve 1b.
That the limited drive circuit 11 is used. The operation up to this point is the same as the operation of the second embodiment. Next, when it is determined in step 4 that it is in the open state, the process proceeds to step 7 and the transient response detecting unit 15 sets the transient state at the time when the second determination time T6 has elapsed since the driving of the first limiting drive circuit 7. The response potential is compared with the reference potential Vref,
An H or L potential corresponding to the determination result is output. Next, in step 8, it is checked whether the output potential is H or L.

Here, when the second limiting drive circuit 11 having a low value of the limiting resistance is operated, the potential of the transient response in the open state of the shut-off valve 1a having a large value of the equivalent inductance is the second determination time T6. If the output potential is L, the control unit 23 proceeds to step 9 to set the shut-off valve 1 to a longer time than the reference potential Vref.
Judge that the connection state is unconnected or abnormal due to a connection error, and terminate abnormally as the limited drive circuit selection is not completed. If the output potential is H in step 8, the shut-off valve 1 is normal and the judgment result based on the judgment time T3 is true. Therefore, it is judged in step 10 that the shut-off valve is 1a.
In step 11, the storage means 22 stores the use of the first limited drive circuit 7. The other operations are the same as those of the gas shut-off device of the first embodiment, and therefore the description is omitted.

As described above, the gas shut-off device of this embodiment
When the shut-off valves that are assumed to be used are the shut-off valve 1a and the shut-off valve 1b, the limited drive circuit selecting means 33 is activated upon receiving a learning start instruction by a return signal at the start of use or a trigger such as communication, and the drive circuit 4 and the first limiting drive circuit 7 are operated, the state of the shut-off valve 1 at that time is compared with the determination result based on the determination time T3, and if they do not match, the other second limiting drive circuit 11 is appropriate. Is determined, and if they match, the result of the determination by the second determination time T6 is compared with the state of the shutoff valve 1, and if they match, the first limiting drive circuit 7 is appropriate. If it does not match, it is determined that there is a suitable limiting drive circuit by storing a connection error or an abnormal operation of the shut-off valve 1 and storing it, and an abnormal state is detected. Depending on different specifications and manufacturer's shut-off valve Is used, the selection of the first drive circuit 7 or the second drive circuit 11 is not required to be written into the storage means 22 by an active means such as a dip switch or communication. Since the means 33 learns and writes, the open / close state of the shut-off valve 1 can be reliably detected by one type of control unit 23, and the drive circuit 4, the first limited drive circuit 7 or the second limited drive circuit 11 Since the number of times of operation is reduced, it is possible to provide a gas shut-off device capable of avoiding confusion caused by shutting off a gas passage at the time of determination and reducing power consumption.

In this embodiment, the process of learning the suitability using only the first limiting drive circuit 7 when there are two types of shutoff valves 1 has been described. You may learn using.

The learning process in the present embodiment is performed by comparing the actual open / closed state of the shut-off valve 1 with the judgment result using the judgment time T3, and by checking the second judgment time T longer than the judgment time T3.
6 is based on the detection of the open / closed state and the abnormal state by comparison with the determination result using FIG. 6, and it goes without saying that the processing is not limited to the processing shown in FIG.

[0061]

According to the first aspect of the present invention, when a shut-off valve of a different specification or a different manufacturer is used in combination, a plurality of limiting drive circuits having limiting resistors adapted to the respective specifications are provided. Which of these limit drive circuits is to be used is stored in advance in the storage means, the appropriate limit drive circuit stored in the storage means is operated, and the state of the transient response of the shut-off valve at that time is detected as a transient response. Part,
By using a gas shut-off device that detects the open / closed state of the shut-off valve based on the result, even if the shut-off valves of different specifications and manufacturers are used together, the open / closed state of the shut-off valve can be ensured by one type of control unit Can be detected.

According to a second aspect of the present invention, there is provided a limiting drive circuit selecting means, and which limit drive circuit is adapted by comparing the actual open / closed state of the shut-off valve with the open / closed state determined based on the state of the transient response. The gas shut-off device according to claim 1, which learns whether or not the limiting drive circuit is compatible with a shut-off valve of a different specification or a different manufacturer. Need not be stored in the storage means in advance, and the open / closed state of the shut-off valve can be reliably detected by one type of control unit.

According to a third aspect of the present invention, the open / close state of the shut-off valve is determined based on the state of the transient response at the time when one predetermined determination time has elapsed since the operation of the limiting drive circuit. And the state of the shut-off valve is compared with each other to determine which of the limited drive circuits is suitable. The gas shut-off device according to any one of claims 1 and 2, Based on the comparison between the two states and the determination result based on the state of the transient response, it is possible to specify a suitable limiting drive circuit or detect an abnormal state of the shutoff valve.

According to a fourth aspect of the present invention, the open / close of the shutoff valve is determined based on the state of each transient response at the time when two predetermined determination times have elapsed since the operation of the limiting drive circuit. The gas shut-off device according to claim 2, wherein the judgment result and one state of the shut-off valve are compared to judge which of the limited drive circuits is suitable, so that the state of the shut-off valve is not changed. It can identify the limiting drive circuit that conforms to the requirements, detect the abnormal state of the shut-off valve, reduce the number of times that the shut-off valve is opened and closed, and operate the limiting drive circuit, avoiding confusion due to shutting off the gas passage. Thus, power consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of a gas shutoff device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a schematic configuration of a shut-off valve used in the first embodiment.

FIG. 3 is a characteristic diagram showing a transient response in the first embodiment.

FIG. 4 is a circuit diagram showing a configuration of a gas cutoff device according to a second embodiment of the present invention.

FIG. 5 is a characteristic diagram showing a transient response in the second embodiment.

FIG. 6 is a flowchart showing the operation of a limited drive circuit selecting unit according to the second embodiment.

FIG. 7 is a flowchart showing the operation of the gas shut-off device in Embodiment 3 of the present invention.

FIG. 8 is a circuit diagram showing a configuration of a conventional gas shut-off device.

FIG. 9 is a characteristic diagram showing a transient response in the conventional example.

[Explanation of symbols]

1, 1a, 1b Shutoff valve 2, 102 Equivalent resistance 3, 103 Equivalent inductance 4, 104 Drive circuit 5, 9, 13, 105, 109 Transistor 6, 10, 14, 16, 17, 18, 19, 106, 1
DESCRIPTION OF SYMBOLS 10 Resistance 7 1st limiting drive circuit 8 1st limiting resistor 11 2nd limiting drive circuit 12 2nd limiting resistor 15 Transient response detection part 20 Comparator 21 Flow rate measuring means 22 Storage means 23,117 Control part 24 Notification means Reference Signs List 25 input means 26, 119 battery 27 permanent magnet 28 yoke 29 movable iron core 30 electromagnetic coil 31 valve 32 spring 33 limited drive circuit selecting means 101 cutoff valve 107 limited drive circuit 108 limited resistance 111 transient response detector 112, 113, 114 Resistance 115 Comparator 116 Flow rate measuring means 118 Display

Claims (4)

[Claims] 1. A flow rate measuring means for measuring a passing gas flow rate, a shutoff valve for shutting off a gas passage, a drive circuit for opening and closing the shutoff valve, and a shutoff valve which is assumed to be used as the shutoff valve. A plurality of limited drive circuits that apply a voltage to the shut-off valve via a limiting resistor that is set in conformity with the corresponding shut-off valve without an opening / closing operation; and A storage means for storing in advance which limit drive circuit is suitable for the actually used shut-off valve, and a transient response of the shut-off valve when operating the limit drive circuit, A transient response detection unit that detects and outputs a situation, a control unit that controls the entire operation, and a battery as a power supply, the control unit is configured to detect an abnormal flow pattern by the flow measurement unit. Drive The shut-off valve is closed by an operating circuit, and a suitable limiting drive circuit stored in the storage means is operated as necessary, and the shut-off is performed based on the state of the transient response detected by the transient response detection unit. A gas shut-off device that detects the open / closed state of a valve. 2. The control section includes a limited drive circuit selecting means,
The limiting drive circuit selecting means detects the open / close state of the shut-off valve based on the state of the transient response when individually operating the limit drive circuit, and compares the detection result with the actual open / close state as a determination. 2. The gas shut-off device according to claim 1, wherein a limiting drive circuit suitable for the shut-off valve is specified and output to a storage means to be stored in advance. 3. The control unit has one determination time for referring to a state of the transient response detected by the transient response detection unit, and the transient response at the time when the determination time has elapsed since the operation of the limited drive circuit. The gas shut-off device according to claim 1 or 2, wherein the open / close state of the shut-off valve is detected by inputting the state of (1). 4. The control unit includes: a first determination time for referring to a status of a transient response detected by the transient response detection unit;
A second determination time longer than that, and detecting the open / closed state of the shut-off valve based on the state of the transient response at the time when the first determination time has elapsed since the operation of the limiting drive circuit.
3. The gas shut-off device according to claim 1, wherein the detection result is confirmed based on a state of a transient response at the time when the determination time has elapsed. 4.