JPH0644939B2 - Gas shutoff device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a gas leak or a gas supply path that is automatically shut off when gas is abnormally used to prevent an accident such as an explosion or a poisoning accident due to city gas or propane gas. The present invention relates to a gas shutoff device that prevents the occurrence of the gas.

2. Description of the Related Art A conventional gas shutoff device of this type is as shown in FIG.
Flow rate measuring means 1 which emits a signal according to the amount of passing gas of a gas meter provided in a gas supply line, calculation unit 2 which calculates the amount of gas passing through the gas meter by a signal from the flow rate measuring unit, and calculation by the calculating unit A division determination unit 3 that calculates the individual gas flow rate from the change in the gas amount and determines to which of the gas flow rate divisions previously divided into a plurality of portions, continuously corresponding to the plurality of gas flow rate divisions. Use time setting changing unit 4 for setting the allowable use time, continuous use time after the individual gas flow rate calculated by the classification determination unit starts to flow, and the use time is preset A use time determination unit 5 that makes a cutoff determination when the allowable time is exceeded, an alarm device input determination unit 6 that determines the presence or absence of a signal from a gas leak alarm device, the use time determination unit or the alarm device input determination A control unit 8 which further the blocking signal output section 7 for outputting a blocking signal in the signal from, and a blocking means 9 for blocking the gas passage in response to a signal from the control unit. Reference numeral 10 is a gas leak alarm that outputs a predetermined signal when a gas leak is detected. Further, reference numeral 11 is a use time setter that sets an allowable time that can be continuously used from the outside.

Here, the permissible time that can be continuously used as a cutoff condition is a predetermined gas combustion amount, that is, for each predetermined gas flow rate range, from statistical data of the time when a gas appliance having a gas flow rate is continuously used. Even if the gas appliance is forgotten to be turned off, etc., it sends an operation signal to shut off when the set judgment time exceeds the set time based on the data from the classification judgment section. This is a condition for ensuring safety.

In FIG. 3, the horizontal axis shows the gas flow rate and the vertical axis shows the continuous use allowable time, and the continuous use allowable time corresponding to the gas flow rate regions (1, 2, ... 6) grouped into predetermined gas flow rate ranges. It is shown. In the figure, L1 represents the first allowable continuous use time, and L2 represents the second allowable continuous use time. That is, the amount of gas leaked when a predetermined value is applied to the ventilation rate in a room of a predetermined size (for example, 6 tatami mats) (for example, 1
From m ³ / h), the corresponding time domain is defined. L2 indicates a gas leakage allowable range in a range that does not lead to a large gas accident when considering the natural ventilation rate as described above. L1 is a special gas appliance (for example,
The table shows the allowable range when the continuous use time becomes long when using (slow heating water heater, etc.). However, since there is a risk that the amount of gas leakage increases in L1, it is actually used in conjunction with the gas leakage alarm device. Therefore, in the conventional gas shutoff device, the gas leak alarm is installed, and after confirming that the gas leak alarm is connected to the control unit, the allowable time of L1 is set.

FIG. 2 shows the concept of detecting which gas flow range value has flowed and how many minutes have been continuously used from the gas flow rate passing through the gas supply system. The horizontal axis represents elapsed time and the vertical axis represents gas flow rate. That is, the total gas flow rate at each time of passing through the gas meter is detected by the flow rate measuring means 1 and the calculation unit 2. On the time axis, the gas flow rate Q ₁ is detected at t = t ₀ , and the continuous use time for the Q ₁ is measured. At t = t ₁ , the gas flow rate becomes Q ₃ , and the classification determination unit 3 determines that the gas flow rate has increased by O ₂ = O ₃ −O ₁ , and the continuous use time is also measured for this Q ₂ . At t = _{t 2,} the gas flow rate _{Q 1,} and the continuous use time _{Q 2 'is} determined to have a _{T 2} of the t 1 ~t _2.
Also, clocking for _{Q 1} also _{t 2} later is carried out continuously, it is determined that ended at t = _{t 3,} it is determined that the continuous use time was _{T 1} of the _t 0 ~t _3. That is, the usage time for each gas flow rate is measured as described above, and when the value exceeds the allowable value shown in FIG. 3, the gas shutoff operation is performed.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-mentioned configuration, when the gas leak alarm is installed and the signal thereof operates in conjunction with the control unit, the installer of the gas shutoff device, etc. However, the allowable time was set using the usage time setting device. However, when the alarm device was removed during use, it was necessary to change the permissible time, and sometimes the troublesome time changing operation was not performed.

The present invention solves such a conventional problem, and provides a safer gas shutoff device having a function of discriminating connection / non-connection of a gas leak alarm and automatically changing setting of shutoff conditions. The purpose is to

Means for Solving the Problems In order to solve the above problems, the gas shutoff device of the present invention is a flow rate measuring unit that emits a signal according to the amount of passing gas of a gas meter provided in a gas supply line, and the flow rate measuring unit. A calculation unit for calculating the gas amount passing through the gas meter by a signal from, a section for determining to which one of the gas flow rate sections divided in advance by calculating the individual gas flow rate from the change in the gas amount calculated by the calculation section A determination unit, a usage time setting change unit that sets an allowable time that can be continuously used corresponding to the plurality of divided gas flow rates, and an individual gas flow rate calculated by the classification determination unit after starting to flow. A usage time determination unit that measures continuous usage time and makes a disconnection determination when the usage time exceeds a preset allowable usage time,
An alarm device input determination unit that determines the presence or absence of a signal from the gas leak alarm device, a shutdown signal output unit that outputs a shutdown signal by a signal from the usage time determination unit or the alarm device input determination unit,
A control unit including an alarm device connection identifying unit that identifies whether or not the gas leak alarm device is connected and sends a signal to the usage time setting changing unit, and a gas passage according to a cutoff signal from the control unit. It is provided with a configuration of a blocking means for blocking.

Action The present invention, by the above-described configuration, determines whether or not the gas leak alarm is connected by the alarm connection identification unit,
The determination signal is transmitted to the use time setting changing unit, and the allowable time continuously usable corresponding to whether or not the alarm device is connected is automatically changed.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a functional block diagram of the gas shutoff device of the present invention. In the figure, blocks having the same numbers as in FIG. 4 are components having the same function. Reference numeral 12 is a use time setting changing unit, which sets allowable time data that can be continuously used in the use time determining unit 5 in response to a signal from the alarm device connection identifying unit 13. Reference numeral 14 is a control unit having the use time setting changing unit and an alarm device connection identifying unit.

In the above configuration, whether or not the gas leak alarm device 10 is connected is determined by the alarm device connection identifying unit 13,
The continuous use time is changed depending on whether or not there is a connection. Further, the alarm device input determination unit 6 receives a signal from the gas leak alarm device 10 when a gas leak occurs and sends a signal to the shutoff signal output unit 7 to perform a shutoff operation.

By the way, the alarm device connection identification unit 13 is used for the gas leak alarm device 1.
Various means such as connection determination using a circuit element that constitutes 0 (for example, a rectifying element for preventing reverse connection of a line) or connection determination using a pulse signal from an alarm device or a voltage signal Can be identified by. further,
Not only the presence / absence of the connection, but also the alarm device using the commercial power supply can be configured to be able to determine not only the content of the alarm device that does not operate at the time of power failure.

As described above, in the gas shutoff device of the present invention, by automatically identifying the alarm device connection, while maintaining the convenience in gas utilization,
When the gas leak detection function of the alarm device is secured, the disconnection condition is set to a predetermined value after confirming the connection of the alarm device, so that safety certainty is improved.

Further, as another embodiment of the present invention, as described above with reference to FIG. 3, the use time setting changing unit 12 includes the first continuous use allowable time corresponding to the gas flow rate section and the second continuous use time shorter than the first time.
Has a continuous use allowable time of 1) and has a first continuous use allowable time when the alarm device is connected in accordance with the signal from the alarm device connection identifying unit, and a second continuous use allowable time when the alarm device is not connected. It is configured to change the allowable continuous use time of. That is, in the case where the gas leak alarm device operates in conjunction with each other and the alarm device is connected, the continuous use permissible time L1 for households such as slow heating water heaters is applied. It is the one to try.

Effects of the Invention As described above, the gas cutoff device of the present invention has the following effects.

(1) Special gas combustion appliances (for example, slow heating water heater)
In some cases, it is normal to use the product continuously for longer than the allowable continuous use time set as the lowest level for gas leak accidents. Installation and its operation is required to work with the gas shutoff device. Therefore, the connection of the gas leak alarm is automatically identified, and the predetermined allowable continuous use time is automatically set, so that the convenience in using the device is maintained and the safety is secured. In addition, if the alarm is removed during use, the time for resetting the allowable continuous use time can be saved, and the setting can be changed reliably, so shut off if gas usage is determined to be abnormal. Since the means is activated and the gas supply is stopped, there is an effect that a dangerous state such as gas poisoning or gas explosion can be prevented in advance.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a gas shutoff device in one embodiment of the present invention, FIG. 2 is a characteristic diagram showing changes in gas flow rate, and FIG. 3 is a characteristic diagram showing relationship between gas flow rate and allowable continuous use time, FIG. 4 is a functional block diagram of a conventional gas shutoff device. 1 ... Flow rate measuring means, 2 ... Calculation section, 3 ... Classification determination section, 5 ... Usage time determination section, 6 ... Alarm input determination section,
7: Shutdown signal output section, 9 ... Shutdown means, 12 ... Use time setting change section, 13 ... Alarm device connection identification section, 14 ...
Control unit.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroshi Horii 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Ichitaka Asano 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Shinzo Kato 2-16-4 Tadao, Machida, Tokyo Metropolitan Gas Safety Association Liquefied Petroleum Gas Laboratory (72) Inventor Mitsuo Namba 2-16-4 Tadao, Machida, Tokyo High-pressure gas Liquefied petroleum gas research institute of the Japan Security Association (72) Inventor Reihei Uematsu 2-16-4 Tadao, Machida, Tokyo High-pressure gas

Claims (2)

[Claims] 1. A flow rate measuring means for outputting a signal in accordance with a passing gas amount of a gas meter provided in a gas supply line, a computing section for computing the gas meter passing gas amount with a signal from the flow rate measuring means, and the computing. A division determination unit that calculates the individual gas flow rate from the change in the gas amount calculated by the section and determines which of the gas flow rate divisions is divided into a plurality of parts in advance, which is continuous corresponding to the plurality of gas flow rate divisions. The usage time setting change section that sets the allowable usage time, and the continuous usage time after the individual gas flow rate calculated by the classification determination section begins to flow is used and the usage time is preset Time judgment unit that makes a cutoff judgment when the allowable time is exceeded, an alarm device input judgment unit that judges the presence / absence of a signal from a gas leak alarm device, the usage time judgment unit or the alarm device input judgment A shutoff signal output unit that outputs a shutoff signal by a signal from the control unit, and a control unit that includes an alarm device connection identification unit that identifies whether the gas leak alarm device is connected and sends a signal to the usage time setting change unit. A gas shutoff device that shuts off the gas passage in response to a shutoff signal from the control unit. 2. The use time setting changing unit has a first continuous use allowable time corresponding to a gas flow rate category and a second continuous use allowable time shorter than the first time, and the alarm device connection identification. When the alarm device is connected according to the signal from the section, the first continuous use allowable time is set, and when it is not connected, the second continuous use allowable time is set and changed. The gas shutoff device according to claim 1.