JP2007298255A - Gas shutoff device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein, when a motion conversion mechanism of a gas shutoff device is clogged with a foreign substance to disturb its shutoff operation, it is unlikely to shut off gas even if no matter how many times the shutoff operation is executed. <P>SOLUTION: The flow rate of gas flowing through a flow-rate detection part 24 is detected after a shutoff operation of a shutoff valve. When the flow rate detected by the flow-rate detection part 24 is above a predetermined flow-rate value, the shutoff valve is driven in a return direction opposite to the shutoff direction by a shutoff driving part 26. The drive in the return direction is continued until a predetermined period elapses, and a normal shutoff operation is executed in the shutoff direction by the shutoff driving part 26 after the predetermined period elapses. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gas shut-off device that prevents a gas accident.

  Conventionally, as shown in FIG. 7, this type of gas shut-off device includes a shut-off valve 3 that is built in the gas meter 1 and shuts off the gas flow path 2, a flow rate detection unit 4 that uses a flow rate sensor that detects the flow rate of gas, When the flow rate signal 5 of the flow rate detection unit 4 is greater than or equal to a predetermined flow rate, the flow rate determination unit 8 that outputs the cutoff signal 7 to the cutoff drive unit 6 that drives the cutoff valve 3 and the cutoff that stores the output of the cutoff signal 7 When the state of the storage unit 9 and the shut-off storage unit 9 is shut off and the flow rate detection unit 4 outputs the flow rate signal 5, the flow rate during shutoff is output to output the cutoff signal 10 to the cutoff drive unit 6. It is comprised from the determination part 11 and the power supply part 13 by the battery etc. which supply electric power to these control parts 4-11 and the cutoff valve 3. FIG.

  In a normal state where there is no danger in using the gas, the shut-off valve 3 is in an open state and supplies gas to a gas appliance or the like downstream of the gas meter 2 (not shown). If the gas flow rate is detected at this time, the flow rate detection unit 4 outputs a flow rate signal 5.

  When the flow rate detection unit 8 determines that the gas consumption pattern is abnormal, such as when the flow rate signal 5 is an abnormally large flow rate, or when the continuation of the flow rate signal 5 is abnormally long due to a timer means (not shown) The shutoff signal 7 is output to the shutoff drive unit 6 to drive the shutoff valve 3 to shut off the gas flow path 2, and at the same time, the shutoff storage unit 9 stores the shutoff drive.

After this, when the flow rate detection unit 4 detects the flow rate, the flow rate signal 5 is output to the abnormality determination unit 11 during interruption, and when the memory of the interruption storage unit 9 is being interrupted, the determination unit 11 with flow rate during interruption is an interruption drive unit The shut-off signal 10 is output to 6 and the shut-off drive unit 6 drives the shut-off valve to shut off again. Thus, the gas shut-off device of FIG. 7 has a structure in which the shut-off operation is performed again when there is a flow rate during shut-off (see, for example, Patent Document 1).
JP 59-69618

  Currently, a motor type shut-off valve using a stepping motor is generally used as the shut-off valve device. The motor type shut-off valve converts the rotational motion of the output shaft of the stepping motor into a linear motion by a motion conversion mechanism such as a worm gear mechanism or a cam mechanism, moves the valve body, and opens and closes the flow path.

  However, in the above-described conventional configuration, when the valve body is determined to be abnormal, the valve element operates only in the direction of blocking the flow path. Therefore, when a foreign substance enters the motion conversion mechanism of the shut-off valve device and acts to hinder the blocking direction. However, there is a problem that the valve body cannot be normally linearly operated and the flow path cannot be blocked, or the possibility that the valve body can be blocked even if a plurality of blocking operations are performed is low.

  In view of such a conventional problem, the present invention increases the probability that the shutoff valve can shut off the gas flow path even when foreign matter enters the motion conversion mechanism of the shutoff valve device and cannot shut off the gas shutoff device with higher safety. The purpose is to provide.

In order to solve the above-mentioned problem, the gas shut-off device of the present invention drives the shut-off means in a gas shut-off means having a flow rate detecting means for detecting the flow rate flowing through the flow path and a shut-off means for shutting off the flow path. When the flow rate detection means later detects a flow rate of a predetermined amount or more, the cutoff means is driven in the cutoff direction after the cutoff means is driven in the direction opposite to the cutoff.

  According to this, when foreign matter enters the motion conversion mechanism of the shut-off valve device and cannot be shut off, the foreign matter is converted into motion by driving in the direction opposite to the shut-off direction once and returning to the state before the foreign matter is clogged in the motion conversion mechanism. It is possible to make it possible to be disconnected from the mechanism. Thereby, it is possible to increase the probability that the shutoff valve can shut off the gas flow path and provide a safer gas shutoff device.

  As described above, according to the gas shut-off device of the present invention, even if foreign matter enters the motion conversion mechanism of the shut-off valve device and cannot be shut off, the motion conversion mechanism is once driven in the direction opposite to the shut-off direction. Therefore, the foreign matter can easily come off, and the probability that the shutoff valve can shut off the gas flow path can be increased, and the safety can be improved.

  The first invention relates to a gas shut-off device. When it is detected that the shut-off means for shutting off the flow path and the flow path is not completely shut off after the shut-off operation of the flow path, the shut-off means is reverse to the shut-off direction. After being driven in the direction, the shut-off control for driving in the shut-off direction is performed.

  With this configuration, when it is detected that the flow path blocking operation of the blocking means is incomplete after the flow path blocking operation, the blocking valve device is driven in the blocking direction after being driven in the direction opposite to the blocking, thereby Even if a foreign substance that impedes the blocking operation enters, the valve operation in the reverse direction increases the probability that the foreign substance is removed and the gas flow path is blocked.

  The second invention relates to a gas shut-off device, which has a flow rate detecting means for detecting a flow rate flowing through a flow path, a shut-off means for shutting off the flow path, and a shut-off drive unit for controlling the shut-off drive by the shut-off means. In the shut-off device, when the flow rate detecting means detects a flow rate greater than or equal to a predetermined amount after the shut-off means is driven to shut off, the shut-off drive unit drives the shut-off means in the direction opposite to the shut-off direction and then drives in the shut-off direction.

  With this configuration, when the flow rate detection means detects a flow rate of a predetermined amount or more, even if foreign matter that would block the shutoff operation enters the shutoff valve device, the foreign matter is removed by the valve operation in the reverse direction. Probability of blocking the road increases.

  The third invention relates to a gas shut-off device, and includes a flow rate detecting means for detecting a flow rate flowing through the flow path, a shut-off means for shutting off the flow path, and a shut-off drive unit for controlling the drive of the shut-off by the shut-off means. The gas shut-off device is equipped with an open / close detecting means for detecting whether the shut-off valve is opened / closed after the shut-off means is driven to shut off, and when the open / close detecting means cannot detect the closing by the shut-off means, the shut-off means is driven in the direction opposite to the shut-off direction. After that, the shut-off control for driving in the shut-off direction is performed.

  With this configuration, when the shutoff is in progress and the open / close detection means is incomplete while shutting off, the valve operation in the reverse direction increases the probability that foreign matter is removed and the gas flow path is shut off.

  In a fourth aspect of the invention, particularly in the first to third aspects of the invention, when it is detected that the flow path is not blocked after the flow path blocking operation, the position where the cutoff valve does not reach the fully open position in the direction opposite to the cutoff direction To drive up to.

With this configuration, when it is detected that the flow path blocking operation of the blocking means is incomplete after the flow path blocking operation, it is not driven until the shut-off valve is fully opened in the direction opposite to the blocking direction, but is driven halfway By doing so, the probability that the foreign substance is removed and the gas flow path is shut off is increased while suppressing power consumption.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram of a gas cutoff device in the present embodiment. In FIG. 1, a gas meter 21 includes a shutoff valve 23 capable of shutting off a gas flow path 22, a flow rate detection unit 24 for detecting a gas flow rate, a microcomputer 32 for controlling the operation, and a power source unit for supplying power thereto. 33 is built-in.

  The shut-off valve 23 includes, for example, a PM type stepping motor, and the flow rate detection unit 24 includes a magnetic sensor, a pressure sensor, an ultrasonic sensor, a heat ray flow sensor, a fluid element sensor, a mass flow sensor, a float sensor, and the like. The microcomputer 32 stores a flow rate determination unit 28, a cutoff storage unit 29, a cutoff flow rate determination unit 31, and a cutoff drive unit 26, which are realized by software means, a logic IC, or the like.

  The gas meter 21 monitors the status of sensors such as an earthquake sensor, a gas pressure sensor, a gas alarm device, and a carbon monoxide sensor when the flow determination unit 28 determines that the usage state of the gas is abnormal use. If it is determined, the gas is shut off by the shut-off valve 23. If it is determined that the gas is not abnormally used or not in a dangerous state, the gas is supplied to a downstream gas appliance.

  The operation and action of the gas shut-off device configured as described above will be described below.

  When gas flows through the gas flow path 22, the flow rate detection unit 24 detects the flow rate and outputs a flow rate signal 25. When the flow rate signal 25 indicates an abnormal flow rate, the flow rate determination unit 28 outputs a cutoff signal 27 to the cutoff drive unit 26 that drives the cutoff valve 23 and the cutoff storage unit 29 that stores the cutoff operation. The interrupting flow rate determining unit 31 that receives the signal of the blocking storage unit 29 and the flow rate signal 25 of the flow rate detecting unit 24 is configured by two input AND gates and outputs a blocking signal 30. Specifically, the determination unit 31 having a flow rate during shut-off will be described. When the state of the shut-off storage unit 29 is being shut off, and the flow rate detection unit 24 determines that there is a flow rate above a predetermined flow rate Q0, the shut-off drive unit 26 The shut-off signal 30 is output.

  The cutoff drive unit 26 receives the cutoff signal 27 and drives the cutoff valve 23 in the normal cutoff direction or drive amount. When the shut-off signal 30 is received, that is, when the shut-off storage unit 29 is shut off and the flow rate during shut-off is detected, a shut-off valve 23 performs a normal shut-off operation. Drive in the return direction opposite to the direction, and then drive with a drive amount that can be shut off again in the shut-off direction.

  Next, processing when the shut-off valve 23 is driven in the return direction opposite to the direction in which the normal shut-off operation is performed will be described with reference to the flowchart shown in FIG. First, after the shut-off operation, the flow rate of the gas flowing through the flow rate detection unit 24 is detected (step 201), and it is determined whether the detected flow rate is a predetermined flow rate value (step 202).

If it is determined that the flow rate detected in step 202 is the flow rate, the shut-off storage unit 29 increments a shut-off counter indicating the number of shut-off operations during the shut-off (step 203), and the shut-off valve 23 serves as a shut-off drive unit. 26 is driven in the return direction opposite to the shut-off direction (step 20).
4) Thereafter, a normal cutoff operation is performed in the cutoff direction by the cutoff drive unit 26 (step 205).

  Steps 201 to 205 are repeated every time a predetermined flow rate value is detected. When the predetermined flow rate value is not detected, the cutoff counter is cleared to zero (step 206), and the process is terminated.

  If a predetermined flow rate value continues to be detected by the flow rate detection unit 24 due to a failure of the shut-off valve, etc., a process for stopping the shut-off valve drive is added when the shut-off counter exceeds a predetermined value. It is possible to prevent the valve 23 from continuously operating in the shut-off direction or the return direction, and to suppress wasteful power consumption.

  Further, a specific driving method of the cutoff driving unit 26 shown in steps 204 and 205 will be described in more detail with reference to the flowchart shown in FIG.

  In FIG. 3, when the cutoff signal 30 is input to the cutoff drive unit 26, the drive timer T is started (step 301). It is determined whether or not the drive timer T has reached a predetermined time (step 302). If the drive timer T has not reached the predetermined time, the cutoff valve 23 is driven in a return direction opposite to the cutoff direction (step 303). . When the shut-off timer reaches a predetermined time, the shut-off valve 23 is driven so as to shut off the gas flow path in the shut-off direction (step 304). That is, it is driven in the return direction only for a predetermined time, and a normal shut-off operation is performed beyond that. The operation of the shut-off valve 23 is determined by such driving.

  As described above, when it is determined that the gas flow path 22 is not completely shut off after the shut-off operation, it is not driven until the shut-off valve is fully opened in the return direction, but is driven only for a predetermined time, thereby reducing power consumption. It is possible to remove foreign substances that interfere with the motion conversion mechanism of the shut-off device, that is, shut-off while suppressing. Furthermore, it is possible to provide a safer gas cutoff device with reduced power consumption.

  The predetermined time in step 303 may be set so that the shut-off valve 23 driven in the reverse direction is completely at the initial driving position (position reaching the fully opened position) or does not reach the fully opened position. You may set as follows. In particular, by setting the predetermined time so as not to reach the fully open position, it is possible to increase the probability that foreign substances are removed and the gas flow path is blocked while suppressing power consumption.

  Further, the same effect can be obtained by adjusting the drive amount in the return direction by using various methods such as the drive rotation speed of the stepping motor and the drive pulse instead of the drive timer T.

  The same effect can be obtained when the shutoff valve 23 is not a motor shutoff valve but an electromagnetic solenoid shutoff valve. When it is determined that the electromagnetic solenoid shut-off valve has not completely shut off the gas flow path 22 after the shut-off operation, the valve disc is moved in the return direction opposite to the shut-off direction, and then moved in the shut-off direction. When foreign matter cannot be blocked from the linear motion mechanism that moves the foreign matter, that is, the probability that the foreign matter is removed and blocked can be increased.

  As described above, according to the gas shut-off device of the first embodiment, when a predetermined flow rate value is detected after the shut-off operation, the valve is driven in the opposite direction to the shut-off, and then the valve is driven in the shut-off direction. Thus, the motion conversion mechanism of the gas shut-off device, that is, the foreign matter that obstructs the shut-off can be removed to make the shut-off state possible. For this reason, the probability that the shutoff valve 23 can shut off the gas flow path 22 increases, and a safer gas shutoff device can be provided.

(Embodiment 2)
A second embodiment of the gas cutoff device of the present invention will be described with reference to the drawings. In FIG. 4, the same reference numerals as those in FIG. 1 are the same as those in the first embodiment, so that the description thereof will be omitted and different structures will be described below.

  The gas meter 41 includes an open / close detection unit 42 that detects the open / close state of the shut-off valve 23 not shown in FIG. The open / close detection unit 42 includes a limit switch, a magnetic switch, inductance detection means, a search coil, a photo sensor, a pressure sensitive element, and the like. In the microcomputer 32, an incomplete shutoff incomplete determination unit 43 is recorded instead of the interrupted flow rate determination unit 31 in FIG. 1, and is realized by software means, a logic IC, or the like.

  The opening / closing detection unit 42 and the shut-off / closing incomplete determination unit 43 will be further described. After the shut-off valve 23 is shut off, the open / close detection hand unit 42 detects whether the shut-off valve 23 is closing the gas flow path 22. . Further, the incompletely closed / closed incomplete determination unit 43 outputs the cutoff signal 30 by an AND gate or the like of two inputs of the state of the open / close detection unit 42 and the state of the cutoff storage unit 29. Specifically, the incomplete closing / closing determination unit 43 will be described. When the state of the interruption storage unit 29 is being interrupted and the open / close detection unit 42 determines that it is not closed, the interruption drive unit 26 receives an interruption signal. 30 is output. The operation of the cutoff drive unit 26 is the same as that of the first embodiment.

  The opening / closing detector 42 will be further described with reference to FIG. In FIG. 5, the open / close detection unit 42 includes a rod 54, a housing 52, a spring 55, a permanent magnet 53, and a magnetic reed switch 57.

  The shut-off valve 23 is the same as that shown in FIGS. The rod 54 is arranged coaxially with the shut-off valve 23, one end abuts when the shut-off valve 23 is closed, and a permanent magnet 53 is fixed to the other end. The housing 52 holds the rod 54 so as to be slidable. The spring 55 is weaker than the closing force of the shut-off valve 23 and is disposed so as to separate the rod 54 and the gas partition wall 56 in the gas meter. The magnetic reed switch 57 is disposed on the opposite side of the shut-off valve 23 with the gas partition wall 56 interposed therebetween, and is turned on when the permanent magnet 53 approaches and turned off when separated.

  The operation of the open / close detection unit 42 will be described below. When the position of the valve body 51 of the shut-off valve 23 is in the open state as shown in FIG. 5A, the rod 54 is not in contact with the valve body 51 but is biased by the spring 55 and is on the right side in the figure. The permanent magnet 53 is separated from the magnetic reed switch 57, and the magnetic reed switch is in an OFF state.

  When the position of the valve body 51 of the shut-off valve 23 is closed as shown in FIG. 5B, the rod 54 contacts the valve body 51 and is pushed by the closing force of the shut-off valve 23 and moves to the left in the figure. When the permanent magnet 53 approaches the magnetic reed switch 57 and the magnetic reed switch is turned on, the open / closed state of the shutoff valve 23 can be detected as an electric signal.

  During normal driving due to an abnormal flow rate or the like, the cutoff drive unit 26 performs a cutoff operation in the normal cutoff direction or drive amount, the cutoff storage unit 29 is in the cutoff state, and the signal of the open / close detection unit 42 is not closed. In this case, that is, when the magnetic reed switch is incompletely closed during shut-off, the valve is driven in a direction opposite to the direction in which the shut-off valve 23 normally performs the shut-off operation, and then the shut-off valve is driven again in the shut-off direction. .

  FIG. 6 is a flowchart of the gas shutoff device according to the second embodiment of the present invention after detecting any abnormality or danger and once shutting off the gas flow path.

In FIG. 6, after the blocking operation, the opening / closing detection unit 42 first detects whether the gas flow path 22 is blocked (step 601). When it is determined that the gas flow path 22 is not closed, the shut-off storage unit 29 increments a shut-off counter indicating the number of shut-off operations during the shut-off (step 602), and the shut-off valve 23 is shut off in the shut-off drive unit 26. It is driven in the reverse return direction (step 603). Thereafter, a normal shut-off operation is performed in the shut-off direction by the shut-off drive unit 26 (step 604).

  The specific driving method of the cutoff driving unit 26 in Step 603 and Step 604 is the same as that in Steps 204 and 205 described in the first embodiment, and a description thereof will be omitted.

  Thus, according to the gas shutoff device of the second embodiment of the present invention, when the shutoff storage unit 29 is shutting down and the signal of the open / close detection unit 42 is incompletely closed during shutoff, By driving the shut-off valve 23 in the direction opposite to the shut-off direction and then driving the shut-off valve 23 in the shut-off direction, it is possible to remove the foreign matter that obstructs the shut-off, that is, to make the shut-off state possible. It is. For this reason, the probability that the shutoff valve 23 can shut off the gas flow path 22 increases, and a safer gas shutoff device can be provided.

  Moreover, since the same effect as Example 1 is acquired even if the cutoff valve 23 is not a motor type cutoff valve but an electromagnetic solenoid cutoff valve, description is abbreviate | omitted.

  As described above, the gas shutoff device according to the present invention includes various gas media, LP gas, city gas, and hydrogen gas flowing in the pipe using a membrane type, ultrasonic sensor, hot wire sensor, fluidic sensor, and the like. It can be applied to uses such as water meters that measure liquids such as water using measurement or ultrasonic sensors.

1 is a block diagram of a gas cutoff device according to Embodiment 1 of the present invention. Flowchart of the gas cutoff device of Embodiment 1 of the present invention Flowchart of shut-off drive unit of embodiment 1 of the present invention Block diagram of a gas cutoff device according to Embodiment 2 of the present invention (A) Cross-sectional view of the valve opening state of the opening / closing detection unit of Embodiment 1 of the present invention (b) Cross-sectional view of the valve opening state of the opening / closing detection unit of Embodiment 1 of the present invention Flowchart of shut-off drive unit of embodiment 1 of the present invention Block diagram of a conventional gas shut-off device

Explanation of symbols

Reference Signs List 21 Gas meter 22 Gas flow path 23 Blocking means 24 Flow rate detecting means 26 Blocking drive unit 28 Flow rate determining means 29 Blocking storage means 31 Blocking state determining unit 32 Microcomputer 33 Power supply unit 42 Opening / closing detecting unit 43 Blocking interruption / incomplete determination unit

Claims (4)

A blocking means for blocking the flow path, and when it is detected that the flow path is not blocked after the flow blocking action by the blocking means, the blocking means is driven in the direction opposite to the blocking direction and then driven in the blocking direction A gas shut-off device having a shut-off drive unit that performs shut-off control. In a gas shut-off device having a flow rate detecting means for detecting a flow rate flowing through a flow path, a shut-off means for shutting off the flow path, and a shut-off drive unit for controlling the drive of shut-off by the shut-off means, the shut-off means is driven to shut off. After that, when the flow rate detecting means detects a flow rate of a predetermined amount or more, the shut-off drive unit drives the shut-off means in the direction opposite to the shut-off direction and then drives in the shut-off direction. In a gas shut-off device having a flow rate detecting means for detecting a flow rate flowing through a flow path, a shut-off means for shutting off the flow path, and a shut-off drive unit for controlling the drive of shut-off by the shut-off means, the shut-off means is driven to shut off. An open / close detecting means for detecting whether the rear shut-off valve is opened or closed, and when the open / close detecting means cannot detect the closing by the shut-off means, the shut-off drive unit drives the shut-off means in a direction opposite to the shut-off direction and then shuts off A gas shut-off device that is driven in a direction. 2. When it is detected that the flow path is not blocked after the flow path blocking operation by the blocking means, the blocking means is driven to a position that does not reach the fully open position in the direction opposite to the blocking direction. 4. The gas shut-off device according to any one of 3 above.