JPH05248600A - Safety device for gas supply - Google Patents

Abstract

PURPOSE:To suppress the permissible gas leakage per unit time for the fuel gas to be used by the gas appliance which leaks from a gas supplying passage provided indoors freely and to a small amount, detect this permissible gas leakage appropriately and rapidly, and reduce the total gas leakage which is the production of the permissible gas leakage by the required time to detect the gas leaking. CONSTITUTION:A gas appliance such as a gas water heater consumes the specified gas flow rate of the fuel gas supplied from a gas supplying pipe 1 through a gas piping 3, and the gas flow rate signal which is obtained by converting the required gas flow rate with the common unit from a flow rate signal transmitter 22 or the like is appropriately transmitted. Then, a flow rate signal receiver 12 adds the gas flow rate signal, and the integrated required gas flow rate which is consumed by the gas appliance is obtained by the common unit. A gas flow meter 11 measures the supply to the gas piping 3, and the difference between the integrated required gas flow rate and the supplied quantity is compared with the permissible leakage by a gas leaking judging device 13, suppressing the total gas leakage from the gas piping to a small value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas supply safety device for safely managing leaks in a gas supply pipe in a home.

[0002]

2. Description of the Related Art Conventionally, this type of gas supply safety device has a standard required gas flow rate for various gas appliances that use fuel gas at each home and a standard continuous use time at this required gas flow rate. According to the so-called pattern control, a usage pattern is set by the gas flow meter, and if the usage pattern of the fuel gas detected by the gas flowmeter with a required time interval deviates from the usage pattern set as described above, a gas leak in the gas supply path is determined. Was adopted.

[0003]

However, in the above-mentioned pattern control, when the required time interval for judging the usage pattern is required and the required detection time for gas leakage is long, and there is a gas leakage of the minimum required gas flow rate. , For example, when a gas-using instrument with a large required gas flow rate is in proportional control operation with a small amount corresponding to the minimum required gas flow rate, this gas leakage cannot be detected, and a unit time of a considerable amount as the minimum required gas flow rate is detected. The fuel gas per hit leaked from the gas supply path for the required detection time, and the total amount of leaked fuel gas was large, which was dangerous, and improvement thereof was desired.

Therefore, the present invention provides a safer gas supply safety device by suppressing the total leakage amount of the fuel gas from the gas supply passage to itself and a small amount.

[0005]

In order to achieve the above-mentioned object, the means of the gas supply safety device of the present invention comprises:
A gas supply passage that receives fuel gas from the gas supply pipe, a gas use device that controls and receives the fuel gas at the required gas flow rate from the gas supply passage, and an allowable leakage amount of fuel gas that leaks from the gas supply passage per unit time. A flow rate signal oscillator that sets a unit gas flow rate that is obtained by dividing the allowable leakage amount by a predetermined safety factor, and converts the control signal of the required gas flow rate of the gas using instrument into a gas flow rate signal that is a multiple of the unit gas flow rate and outputs the signal. And a supply control valve for controlling the supply of the fuel gas to the gas supply path and a gas flow meter for detecting the supply amount with the unit gas flow rate as the minimum unit, and the gas flow rate signal from the flow rate signal oscillator for adding the unit. Deviation between the flow rate signal receiver that calculates the cumulative required gas flow rate of the gas appliance based on the gas flow rate and the amount of fuel gas detected by the gas flow meter to the gas supply path and the cumulative required gas flow rate. The comparison with the permissible leakage amount, those having a gas leakage determination unit for instructing the stop of the supply of fuel gas to the supply control valve to determine the gas leakage of the gas supply channel.

[0006]

With the above-described means, the gas supply safety device of the present invention is such that, when a gas leak occurs from the gas supply passage while the fuel gas is being used by the gas use instrument, the gas use instrument that is using the fuel gas has a required gas flow rate. The flow rate signal transmitter that receives the signal for controlling the gas outputs the gas flow rate signal, and the flow rate signal receiver adds the single or multiple gas flow rate signals to add the required gas of the fuel gas used by the gas using device. Calculate the flow rate.
The gas leak determination device compares the deviation amount of the supply amount of the fuel gas detected by the gas flow meter to the supply path and the deviation value of the cumulative required gas flow rate with the preset allowable leakage amount of the fuel gas, and the deviation value is the allowable leakage amount. If it is more, it is determined that the fuel gas is leaking from the gas supply passage, and the supply control valve is instructed to stop the supply of the fuel gas to the gas supply passage.

At this time, the flow rate signal receiver receives a gas flow rate signal corresponding to the control signal from the flow rate signal transmitter each time the gas use instrument changes the required gas flow rate by proportional control, program control, etc., and uses the gas. By accurately detecting the cumulative required gas flow rate of the equipment, if a gas leak exceeding the allowable leak amount occurs in the gas supply path, the signal of the gas flow rate, the cumulative required gas flow rate, and the supply amount signal are transmitted / received and the calculation process is performed. Gas leakage can be determined in a short time only for the required time.

Further, this determination operation is an allowance for determining the safety factor based on the error in the control, measurement and arithmetic processing of the device, and the risk to the human body due to the diffusion of leaked gas into the room where the gas-using equipment is used. By setting the unit gas flow rate from the leak rate, the gas flow rate signal and the gas flow meter supply rate can be rationally measured and calculated based on the unit gas flow rate, and the time required for gas leak detection can be further shortened. In addition, the allowable leak amount can be freely set to flexibly respond to the operating environment conditions of gas appliances, and the shortened time required for gas leak detection and the gas leak amount per unit time set to a lower value (allowable The total gas leakage amount as an integrated value of the leakage amount) can be suppressed to a smaller amount, and sufficient safety against gas leakage can be secured.

[0009]

Embodiments of the gas supply safety device of the present invention will be specifically described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention, in which a fuel gas drawn from a fuel gas supplier by a gas supply pipe 1 is received by a gas meter 2 and a gas pipe 3 is provided in each room as an indoor gas supply passage. Fuel gas is constantly supplied to the water heater 4, the gas range 5, and the dryer 6 as gas-using equipment via
The gas is also supplied to the gas stove 8 and the like which is used by being connected to the gas stopper 7 as needed. The gas meter 2 is a supply control valve 10 that stops the supply of fuel gas to the gas pipe 3 when a gas leaks, a gas flow meter 11 that measures the passage amount of the fuel gas in a short time and converts it into the supply amount per unit time, and the gas. Receive the gas flow rate signal from the equipment used and convert the added value separately with the unit gas flow rate,
Allowable leak amount of fuel gas that leaks from the gas pipe 3 per unit time by using the deviation value between the supply amount of the flow rate signal receiver 12 and the gas flow meter 11 for calculating the integrated required gas flow rate of the gas using instrument and the integrated required gas flow rate. And a display 14 for displaying the integrated value of the supply amount of the gas flow meter 11 and the like.

Even if the fuel gas leaks while the air is tightly closed by shutting off the doors and windows of a room with good airtightness,
Amount that is not dangerous to humans when dispersed indoors (for example, 0.0
05m ³ = 5l) and set to a level that does not malfunction due to gas leakage when the gas stove 8 is gas-connected to the gas plug 7. In addition, a safety factor (for example, 1.1) is set in consideration of the measurement and calculation errors of the device due to the measurement error of the gas flow meter 11 and the calculation error of the flow rate signal receiver 12, and the safety factor (1.1) is set. The unit gas flow rate (0.045 m ³ = 4.5 l / hour) obtained by dividing the allowable leak amount (0.005 m ³ ) is set by. The allowable leak amount and safety factor are low depending on the dangerous action components contained in the fuel gas to the human body, the tightness of the room to be used, etc. It is possible to further reduce the amount in order to suppress or suppress the amount of gas leakage from the gas plug 7. In addition, when the room is well ventilated from the outside, it increases conversely, so that the supply control valve 10 does not operate very sensitively even if the leak amount at the time of gas connection of the gas stove 8 from the gas plug 7 is large, The gas meter 2 is provided with a permissible amount changer 9 for changing the set value of the permissible leakage amount.

The water heater 4, the gas range 5 and the dryer 5 as the gas use equipment are respectively provided in the combustors 15, 16 and 1.
7. A program for controlling the hot water supply load and the time, such as the required gas flow rate for setting the fuel amount of the combustors 15, 16 and 17,
And a combustion controller 18, 19, which controls according to a predetermined value,
20. Flow rate signal oscillators 22, 23, 24 for receiving a required gas flow rate control signal of the combustion controllers 18, 19, 20 and outputting a gas flow rate signal divided by the unit gas flow rate (4.5 l / hour). Prepare Gas pipe 3 is gas meter 2
When is installed outdoors, the part outside the wall 21 on the roof side is also included. The gas stove 8 does not have electric combustion control, and the combustion controller 25 controls the combustion of the combustor 27 by the operation lever 26 that is manually operated. Then, the combustion controller 25 transmits the required gas flow rate to the flow rate signal oscillator 28 by mechanical means, and the flow rate signal oscillator 28 divides this transmission amount by the unit gas flow rate (4.5 l / hour) into a gas flow rate signal. Convert. The flow rate signal oscillators 22, 23, 24, 28, etc. communicate with the flow rate signal receiver 12 of the gas meter 2 such as gas flow rate signals.

FIG. 2 shows a conversion characteristic in which a required gas flow rate, which changes due to load, program control, or the like, of a gas using instrument changes into a gas flow rate signal. The required gas flow rate is divided by a gas flow rate of a common unit with the unit gas flow rate (4.5 l / hour) as one unit, and is converted into a gas flow rate signal as a multiple of the common unit (1). For example, the required gas flow rate is a predetermined value (1.0 m ³ /
The dryer 6 of (at the time) always outputs a constant gas flow rate signal 222 at the time of operation using gas. For gas appliances that can change the heating capacity according to other loads, such as the water heater 4, the control range is from the minimum value of the required gas flow rate (0.25 m ³ / hour) to the maximum value (2.5 m ³ / hour). Corresponding to 65 to 555
The gas flow rate signal in the range is transmitted from the flow rate signal oscillator 22.

Each gas-using instrument has its own control range of the required gas flow rate, and has a value on the conversion line K (shown with a slight shift in the drawing). Then, a single or a plurality of gas flow rate signals are output according to the operating state of each gas using instrument, and the flow rate signal receiver 12 of the gas meter 2 that has received this signal simply adds the plurality of gas flow rate signals, and It is as simple as multiplying the gas flow rate (4.5 l / hour), and therefore, it can be processed quickly and accurately by a short time arithmetic processing.
It is possible to detect the cumulative required gas flow rate while the gas-using equipment is in use. Comparing this detection operation with the detection method in the conventional pattern control, when the integrated value of the gas usage of the gas usage instrument that is using the fuel gas, which is detected by the gas flow meter in the pattern control, changes, the deviation value due to the change is calculated. Calculate and further detect changes in the required time interval to estimate the type of gas appliance (whether you are using a water heater or a gas range),
Moreover, the presence / absence of gas leakage is determined by waiting for the time determination as to whether or not the usage time exceeds the general usage time interval. As is apparent from this, the speed of the present embodiment can be remarkably increased as compared with the time required for the conventional gas leak detection.

Next, the flowchart of FIG. 3 (step S
1 to S15), a description will be given of the operation when the gas-using appliance is burnt. The gas range 5 is operated in S1, and the flow rate signal oscillator 23 which receives the control signal of the required gas flow rate from the combustion controller 19 in S2 converts the required gas flow rate into a gas flow rate signal and outputs it. The flow rate signal receiver 12 of the gas meter 2 that has received this gas flow rate signal converts the gas flow rate signal into an integrated required gas flow rate (correctly, it is independent data but not an integrated value) and outputs it. On the other hand, the gas flow meter 11 detects the use of the fuel gas by the gas range 5, and uses the gas flow rate detected in a predetermined short time as the gas flow rate per unit time to supply the fuel gas from the supply control valve 10 to the gas pipe 3. Is detected and output (S3).

In S4, the gas leak determination device 13 that has received both the supply amount signal and the integrated required gas flow rate signal compares the deviation value of both signals with the allowable leak amount of the fuel gas stored in advance, and The presence or absence of gas leakage in the gas pipe 3 is determined. The time required for this determination is only the time required for the arithmetic processing of the received signal, and can be shortened if a microcomputer (not shown) is used. If the cumulative required gas flow rate is larger than the supply rate, the fuel gas other than the gas range 5 was used improperly without the output of the gas flow rate signal, or the gas leaked in the gas pipe 3. Means the occurrence of. Therefore, the gas leak determination device 13 immediately instructs the supply control valve 10 to the gas pipe 3 for normal maintenance of the device and for prohibiting unsafe use of fuel gas due to dangerous gas leakage. Stop the supply of fuel gas (S
5).

When there is no gas leakage in S4, the supply of combustion gas from the supply control valve 10 is continued and the valve is continuously opened in S6. The gas range 5 program-controls cooking and changes a required gas flow rate for every predetermined time, and the flow signal oscillator 23 outputs a different gas flow signal each time (S7). Then, the flow from S3 to S6 is repeated, but it is omitted here. At this time, when the water heater 4 is operated at the same time (S8), a gas flow rate signal (currently 555) is also oscillated from the flow rate signal oscillator 22, and the flow rate signal receiver 12 that has received this signal is already in the micro state. The flow rate signal of the gas range 5 (which is now 65) on the RAM of the computer is added, and the flow rate signal of the integrated value 620 is converted into the unit gas flow rate to obtain the integrated required gas flow rate of about 2.8 m ³ / hour. Detect. On the other hand, the gas flow meter 11 detects the supply amount, and the gas leak determination device 13 determines the gas leak (S9). The flow before and after this is omitted in the figure. Also, the explanation of the operation of the determination result is omitted.

At S10, the operation of the gas range 5 is stopped,
When the gas flow meter 11 outputs signals of different supply amounts, S
In 11, the gas leak determination unit 13 determines a gas leak based on the gas flow rate signal of the water heater 4 on the RAM and the supply amount signal. That is, when the gas-using instrument stops operating, the amount of fuel gas supplied to the gas pipe 3 changes, and the gas flow meter 11
Automatically detects this condition.

When the gas controller does not control the gas flow rate correctly with respect to the gas flow rate signal due to deterioration of the combustion controller 18 or the like, the gas leak determining device consumes a gas flow rate higher than the gas flow rate signal. 13 determines that there is a gas leak, detects an abnormal state of the gas-using instrument, and can detect the correct recovery / repair time of the capability. Further, when a gas flow rate lower than the gas flow rate signal is used, the gas leak determination device 13 is
A message to that effect is displayed on 4, and the supply control valve 10 stops the supply of the fuel gas in order to instruct the normal recovery of the capacity of the gas using appliance and to prevent an accident due to unsafe use of the gas using appliance.

Next, in S12, a case where a gas leak occurs in the gas pipe when the gas using tool is not used at all will be described. As described above, the control accuracy of the gas flow rate of the combustion controller 18 and the like must be taken into consideration during the operation of the gas use instrument, but at this time, it is desired to detect even a slight gas leak, and it is under possible conditions. Therefore, when the gas leak determination unit 13 does not continuously receive the gas flow rate signal for a predetermined time, the gas leak determination unit 13 instructs the gas flow meter 11 to give a smaller unit for detecting the supply amount. The gas flow meter 11 uses the unit gas flow rate of 1
It is set to 1/0 or less and input to the gas leak determination device 13 (S
13). In this way, when the gas appliance is not in use, a minute amount of gas leakage can be detected in accordance with the detection accuracy of the gas flow meter 11, and it does not have a negative effect on the time required for gas leakage detection when the gas appliance is used.

Fuel gas is not only harmful to humans,
Depending on the type of fuel gas, the allowable leakage amount may be set to avoid the danger of explosion due to ignition of smoking flames and the like, which may cause an explosion accident.

[0022]

As is clear from the above description, the gas supply safety device of the present invention has the following effects.

(1) The gas leak determination device corresponds to the usage environment condition of the gas-using appliance, and freely sets the allowable leak amount for gas leak determination that occurs in the gas supply passage while the fuel gas is being used in the gas-using appliance. It is possible, and can respond flexibly to the usage environment conditions.

(2) Based on the unit gas flow rate common to the gas use appliances reasonably set by the flow signal oscillator by utilizing the control signal of the required gas flow rate of the gas use appliance, the gas is changed every time the required gas flow rate is changed. The flow rate signal is transmitted, and the flow rate signal receiver can detect the total gas usage amount as the cumulative required gas flow rate of multiple gas usage appliances in a timely and swift manner. The total amount of gas leaked over the required time can be reduced, and the safety in using fuel gas can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a gas supply safety device of the present invention.

FIG. 2 is a characteristic diagram for setting a gas flow rate signal of the device.

FIG. 3 is a flowchart showing the operation of the device.

[Explanation of symbols]

 3 gas piping 10 supply control valve 11 gas flow meter 12 flow signal receiver 13 gas leak determination device 22, 23, 24, 28 flow signal oscillator

Claims (1)

[Claims] 1. A gas supply passage for receiving a fuel gas from a gas supply pipe, a gas use device for controlling and receiving a fuel gas of a required gas flow rate from the gas supply passage, and a fuel leaking from the gas supply passage per unit time. Set the allowable leak amount of gas and the unit gas flow rate that is obtained by dividing this allowable leak amount by the predetermined safety factor, and convert the control signal of the required gas flow rate of the gas using instrument into the gas flow rate signal as a multiple of the unit gas flow rate. A flow rate signal oscillator that outputs, a supply control valve that controls the supply of fuel gas to the gas supply path, a gas flow meter that detects the supply amount with the unit gas flow rate as the minimum unit, and a gas flow rate signal from the flow rate signal oscillator. A flow rate signal receiver for adding and calculating the integrated required gas flow rate of the gas using appliance by the unit gas flow rate, the supply amount of the fuel gas detected by the gas flow meter to the gas supply path, and the integrated required gas flow rate. Compared to the allowable amount of leakage of deviation of the gas supply safety apparatus having a gas leakage determination unit for instructing the stop of the supply of fuel gas to the supply control valve to determine the gas leakage of the gas supply channel.