JP3137511B2 - Used gas appliance discriminator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas appliance discriminating apparatus for discriminating the type of a gas appliance in use in a gas supply system for supplying gas to a gas appliance via a gas meter, and more particularly to a gas governor. The present invention relates to a used gas appliance discriminating apparatus for discriminating a used gas appliance based on the presence or absence of a (pressure regulator).

[0002]

2. Description of the Related Art In a gas meter, there are two representative methods for detecting the occurrence of gas leakage and shutting off gas, namely, an abnormal gas flow rate inspection function and an instrument continuous use time excess inspection function. The former has a function of driving a gas shut-off valve to shut off a gas flow path when an abnormally large gas flow is detected by a gas flow meter, while the latter uses a gas appliance for an abnormally long time. In this case, similarly, the function is to drive the gas cutoff valve to cut off the gas flow path.

As a conventional gas meter to which such a safety function is added, there is a city gas meter equipped with a microcomputer.
As an abnormal gas flow rate inspection function, there are a case where the gas flow path is cut off when the total maximum flow rate is exceeded, and a case where the gas flow path is cut off when the individual maximum flow rate is exceeded. Specific values of the total maximum flow rate and the individual maximum flow rate differ depending on the number of gas meters.

For example, meter numbers 1, 2, 3, 5, 7
In the city gas meter of, the individual maximum flow rate (m ³ / h)
"1.5", "2.8", "4.8", "5.6",
Each is set to “6.9” and the total maximum flow rate (m ³ / h)
Are “1.8”, “3.7”, “5.4”, “8.
8 "and" 12.2 ".

On the other hand, the duration of a gas meter having a function for inspecting the excessive use of the appliance is classified according to the amount of heat, and the calorific value classification (Kcal / h) is -500, -5.
Less than 000, less than -6000, less than -7000, -90
In the categories of less than 00, less than -12000, and less than -14000, the durations (minutes) are "unlimited" and "7
20 "," 720 "," 720 "," 390 "," 39 "
0 "and" 120 ".

[0006]

However, the gas meters having the above-mentioned safety functions have the following problems. That is, in the case of a gas meter having an abnormal gas flow rate inspection function, if a very small amount of gas flows as a gas leak state, it cannot be detected. Therefore, there is a problem that the gas continues to flow without being shut off, resulting in a gas accident. Conversely, when a gas appliance using a high-calorie gas is used for a long time, there is a problem that this is determined to be a gas leak and a malfunction is caused.

[0007] On the other hand, in the case of a gas meter having an equipment continuous use time excess inspection function, a gas leak accident can be prevented beforehand by changing the continuous time according to the gas use amount, but the gas use amount is large. The use time is not as short as the appliance. Therefore, there is a problem that a malfunction is likely to occur.

[0008] In a gas meter having both an abnormal gas flow rate inspection function and an instrument continuous use time excess inspection function as described above, in order to prevent erroneous operation of gas leak detection, a gas instrument used on the gas meter side must be installed. It is indispensable to determine the type. However, in the conventional gas meter, there is no method for effectively discriminating the type of the used gas appliance.

The present invention has been made in view of such a problem, and an object of the present invention is to easily determine a gas appliance to be used by utilizing a relationship between an active fluctuation amount of a gas supply pressure and a gas flow rate. Accordingly, it is an object of the present invention to provide a used gas appliance discriminating apparatus that prevents malfunction of a safety function and enables early detection of gas leakage.

[0010]

According to a first aspect of the present invention, in a gas supply system for supplying gas to a gas appliance via a gas meter having a gas shutoff function, the gas supply pressure in the gas meter is determined. Pressure fluctuation means for actively fluctuating, gas flow rate detection means for detecting the flow rate of the gas whose supply pressure fluctuated by this pressure fluctuation means,
Average value calculating means for calculating an average value of the gas flow rates detected by the gas flow rate detecting means at regular intervals, and whether or not a gas governor is provided in the used gas appliance based on the calculation result of the average value calculating means. And a discriminating means for discriminating the type of the gas appliance to be used based on the result.

In the used gas appliance discriminating apparatus, the gas supply pressure in the gas meter is actively fluctuated by the pressure fluctuation means. The gas flow rate changes due to the fluctuation of the supply pressure,
The gas flow rate is detected by the gas flow rate detecting means, and the average value of the gas flow rate detected by the average value calculating means is calculated at regular intervals. The gas appliance determining means determines whether or not the gas governor used is equipped with a gas governor based on the calculation result of the average value calculating means, and determines the type of the used gas appliance based on the result.

Here, the principle of discriminating the type of used gas appliance according to the present invention will be described.

In general, in a gas meter, when the gas supply pressure is actively varied, when the gas governor (pressure regulator) is installed in the gas appliance to be used (for example, a gas grill), the fluctuation of the gas supply pressure is reduced. Since the gas governor absorbs, there is no influence on the gas flow rate. On the other hand, when there is nothing obstructing the gas flow inside the used gas appliance, that is, when a gas governor is not provided (for example, a gas table), the fluctuation of the gas supply pressure directly affects the gas flow rate. Therefore, in the present invention, whether or not a gas governor is provided, that is, the gas appliance to be used is, for example, a gas grill or a gas, based on the correlation between the fluctuation amount of the average value of the gas flow rate every predetermined time and the active pressure fluctuation amount This is to determine which of the tables it is.

According to a second aspect of the present invention, the gas appliance discriminating apparatus is configured to calculate the average value by the average value calculating means after a predetermined time has elapsed after the pressure fluctuation means has been operated and the gas flow has stabilized. It is.

[0015] In this used gas appliance discriminating apparatus, the data in the state where the gas flow is unstable immediately after the pressure fluctuation means is operated is excluded, so that the type of gas appliance can be discriminated more accurately.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a gas supply system 1 according to one embodiment of the present invention. The gas supply system 1 includes a pipe 1 between a gas meter 10 and a gas appliance 20 formed of, for example, a gas grill or a gas table.
7 for supplying the gas a. The pipe 17 is provided with a gas stopper 17a as opening / closing means.

A gas pipe 11 serving as a gas flow path is provided inside the gas meter 10. In this gas pipe 11,
A pressure fluctuation device 12 as gas pressure fluctuation means, a gas shutoff valve 13 for shutting off a gas flow path at the time of abnormality, a gas pressure sensor 14 for detecting pressure fluctuation by the pressure fluctuation device 12, and a gas flow rate are measured. Gas flow meters 15 are sequentially arranged.

As the pressure fluctuation device 12, any device capable of actively causing pressure fluctuation can be used. For example, a proportional valve is used. According to this proportional valve, it is possible to suppress the pressure fluctuation on the upstream side of the gas meter 10 and cause the same pattern of pressure fluctuation.

FIG. 2 shows the configuration of the control unit 16 in the gas supply system 1 of the present embodiment. This control unit 1
6 has a CPU (central processing unit) 30. CPU
Reference numeral 30 is connected to each unit of the apparatus via a bus. Among them, a ROM (read only memory) 31 stores a control program for determining the gas appliance 20 as shown in a flowchart (FIG. 3) described later.

RAM (random access memory) 3
2 stores data such as a predetermined gas flow rate or the like serving as a gas shutoff reference, and an active pressure fluctuation amount by the pressure fluctuation device 12 and a gas flow rate for each predetermined time, which serve as a determination reference for the gas-using instrument 20. And data representing the correlation with the variation of the average value of. The I / O (input / output) port 33 transmits a drive signal from the CPU 30 to the pressure fluctuation device 1.
2 and an interface for sending each output signal of the pressure fluctuation device 12, the gas pressure sensor 14, and the gas flow meter 15 to the CPU 30.

The CPU 30 sends a drive signal to the pressure fluctuation device 12 to actively fluctuate the supply pressure of the gas a flowing through the gas meter 10 and receives a detection result of the gas pressure sensor 14 accompanying the pressure fluctuation. The fluctuation amount is detected. Further, the CPU 30 receives the output of the gas flow meter 15 and calculates an average value of the gas flow rate that changes due to the pressure fluctuation at regular time intervals. The presence or absence of the gas governor in the appliance 20 is determined, and the type of the gas appliance 20 is determined based on the result.

Here, immediately after the gas supply pressure is changed by the pressure change device 12, the gas flow is unstable. Therefore, in the present embodiment, the ignition pressure is obtained by ignoring the data of the supply pressure and the gas flow rate at the unstable point immediately after the fluctuation, and comparing the magnitude of the average value of the gas flow rate over a certain period of time of the data at the stable point thereafter. It is determined whether or not the gas appliance 20 is equipped with a gas governor.

The CPU 30 also has the above-described abnormal gas flow rate inspection function and the instrument continuous use time excess inspection function, and determines whether or not the gas flow path should be shut off by these safety functions according to the type of the gas instrument 20. When it is determined that the valve should be shut off, a valve shutoff signal is output. I
The / O (input / output) port 34 is an interface for sending the valve shutoff signal to the drive circuit 35. CPU 30
The drive circuit 35 that has received the valve shut-off signal sent from the controller closes the gas shut-off valve 13 and shuts off the gas flow path 11.

Next, the operation of the gas supply system 1 of this embodiment will be described with reference to the flowchart shown in FIG.

First, the CPU 30 sends a drive signal to the pressure fluctuation device 12 and sends the gas a
Is actively changed, for example, at a constant cycle (step S300). Then, the gas supply pressure is detected based on the detection result of the gas pressure sensor 14 (Step S).
301), and the amount of change is detected (step S301).
302). Further, the CPU 30 receives the output of the gas flow meter 15 to detect the gas flow rate (step S303), and after the gas flow is stabilized after a predetermined time (for example, one second) has elapsed from the start of the pressure fluctuation ( In step S304; Y), the average value of the gas flow rate for each fixed time is calculated (step S305). Next, the CPU 30 refers to the gas flow average value and the data representing the correlation stored in the RAM 32 to determine whether the gas appliance 20 is equipped with a gas governor (step S306).
Then, based on the result, the type of the gas appliance 20 is determined, and in this embodiment, it is determined whether the gas appliance 20 is a gas grill or a gas table.
That is, when it is determined that the gas governor is provided (step S306; Y), the gas grill is set, and when it is determined that the gas governor is not provided (step S306; N), the gas table is set.

After the type of the gas appliance 20 has been determined,
The CPU 30 further receives the result of the determination, and determines whether or not to interrupt the gas flow path by using the abnormal gas flow rate inspection function or the tool continuous use time excess inspection function. here,
If it is determined that the gas appliance 20 is equipped with a gas governor, that is, if the gas appliance 20 is a gas grill, there is clearly no possibility of gas leakage. On the other hand, when it is determined that the gas appliance 20 is not equipped with the gas governor, that is, when the gas appliance 20 is a gas table, there is a possibility of gas leakage.

As described above, in the present embodiment, the type of the gas appliance 20 can be easily determined, and the possibility of gas leakage can be determined according to the type. Leaks can be detected early.

It should be noted that after the type of the gas appliance 20 has been determined, it is necessary to determine the presence or absence of gas leakage by the above-described abnormal gas flow rate inspection function or the appliance continuous use time excess inspection function, and to shut off the gas flow path. Gas shut-off valve 1 when judged
The operation of closing 3 is the same as the conventional operation.

FIGS. 4 to 8 show specific examples of the determination of the gas appliance 20 in the present embodiment. FIG. 4 shows a state of pressure fluctuation given by the pressure fluctuation device 12, FIG. 5 shows a state of flow rate change in the gas grill when such pressure fluctuation is given, and FIG. 6 shows a state of flow rate change in the gas table similarly. Respectively. The number of pulses on the vertical axis in FIGS. 5 and 6 corresponds to the gas flow rate.

Further, the data for one second immediately after the fluctuation of the gas pressure are ignored, and the data (gas flow rate) for the subsequent one second are averaged and displayed. FIG. 7 (gas grill) and FIG. ). The data in FIG. 7 shows that the fluctuation of the gas flow rate is small, the gas governor is clearly installed, and the gas appliance 20 is a gas grill. On the other hand, in the data of FIG. 8, the gas flow rate fluctuates greatly, so that no gas governor is provided.
Therefore, it is understood that the gas appliance 20 is a gas table.

The present invention has been described with reference to the embodiments.
The present invention is not limited to the above embodiments, and can be variously modified without changing the gist of the invention. For example, in the above embodiment, as a gas appliance to be determined,
Although the description has been given using the gas grill and the gas table, it is needless to say that the present invention can be applied to determination of other appliances such as a gas stove.

[0033]

As described above, according to the gas appliance discriminating apparatus according to the first aspect, the pressure fluctuation is actively generated, the fluctuation amount of the gas flow rate accompanying the pressure fluctuation is detected, and the detection result is obtained. It is determined whether or not the gas governor is provided in the used gas appliance based on the above, and the type of the used gas appliance is determined based on the result, so that the determination can be easily performed. Therefore, it is possible to detect a gas leak at an early stage, prevent a gas accident from occurring, and improve the safety.

According to the apparatus for discriminating a used gas appliance according to the second aspect of the present invention, the discrimination of the used gas appliance is made after a predetermined time has elapsed after the pressure fluctuation and the gas flow is stabilized. Therefore, it is possible to determine the used gas appliance more accurately.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a gas supply system according to an embodiment of the present invention in a partial cross section.

FIG. 2 is a block diagram illustrating a configuration of a control unit in the used gas appliance discriminating apparatus according to one embodiment of the present invention.

FIG. 3 is a flowchart for explaining the operation of the used gas appliance discriminating apparatus.

FIG. 4 is a diagram illustrating an example of a pressure change applied to a gas governor.

FIG. 5 is a diagram showing a state of fluctuation of a gas flow rate in the gas grill when the pressure fluctuation of FIG. 4 is given.

6 is a diagram showing a state of fluctuation of a gas flow rate in a gas table when the pressure fluctuation of FIG. 5 is given.

FIG. 7 is a diagram showing average value data of the gas flow rate change shown in FIG. 5 every second.

FIG. 8 is a diagram showing average value data of the gas flow rate change shown in FIG. 6 every second.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas supply system 10 Gas meter 12 Pressure fluctuation device 13 Gas shutoff valve 14 Gas pressure sensor 16 Control unit 30 CPU (central processing unit)

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-191853 (JP, A) JP-A-3-236513 (JP, A) JP-A-2-266229 (JP, A) JP-A 64-64 44824 (JP, A) JP-A-1-110218 (JP, A) JP-A-4-44198 (JP, A) JP-A-64-23626 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01F 3/22

Claims (2)

(57) [Claims] 1. A gas supply system for supplying gas to a gas appliance via a gas meter having a gas shut-off function, comprising: a pressure change unit for actively changing a gas supply pressure in the gas meter; Gas flow rate detecting means for detecting the flow rate of the gas whose pressure has fluctuated; average value calculating means for calculating an average value of the gas flow rates detected by the gas flow rate detecting means at regular intervals; and calculation of the average value calculating means. A use gas appliance discriminating device, comprising: a judgment unit for judging whether or not a gas governor is provided on the used gas appliance based on a result, and discriminating a type of the used gas appliance based on the result. 2. The method according to claim 1, wherein the calculation of the average value by the average value calculation means is performed after a predetermined time has elapsed after the pressure fluctuation means has been operated and the gas flow has stabilized.
Use gas appliance discriminating apparatus as described.