JPH05282574A - Shut-off control unit - Google Patents

Abstract

PURPOSE:To monitor the usage conditions of gas by decision reference which is normally matched with the usage conditions of a gas equipment of a consumer in accordance with the change of seasons, etc. CONSTITUTION:The shut-off control unit is characterized by providing ROM 301 which has a shut-off decision time table where shut-off decision time corresponding to the flow rate classification of the gas equipment is previously stored, RAM 305 which has a continuity time table where the average value of continuity usage time measured in a fixed period after the gas equipment starts working is stored and a control means 201 which shuts off gas supply when gas is permitted to continuously flow into the gas equipment over shut-off decision time in the shut-off decision time table and also which shuts off gas supply based on new shut-off decision time obtained in accordance with the average value of consecutive usage time after the average value of consecutive usage time is stored in the continuity time table.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shutoff control unit built in a gas meter with an automatic shutoff function and having a function of automatically shutting off gas by detecting an abnormality such as a gas flow rate.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional example of a gas meter with an automatic shutoff function.

A gas meter with an automatic shut-off function comprises a gas meter body 11, a vibration sensor 12, a pressure sensor 13, and a shut-off valve 1.
4, a shutoff valve return device 15, a control unit 16 having a one-chip microcomputer 17 and a battery 10, a flow rate sensor 18, and a display device 19 are incorporated.

In the gas meter with the automatic shut-off function having such a configuration, the one-chip microcomputer 17 of the control unit 16 judges the abnormality of the flow rate data detected by the flow rate sensor 18, and operates the shut-off valve 14 to discharge the gas. It has the function of blocking. Further, in the gas meter with the automatic shutoff function, the following five basic functions (abnormality judgment program) are programmed in the ROM in the one-chip microcomputer 17 in order to prevent a gas accident. (1) The gas is shut off by judging an abnormality in the gas flow rate. (2) The gas is shut off when it is judged that the gas equipment has been used for an abnormally long time. (3) The signal from the seismic sensor 12 shuts off the gas in the event of a large earthquake. (4) The gas is shut off when an abnormal drop in the gas supply pressure is detected. (5) Gas is shut off by external signals from the city gas alarm (gas leak alarm), incomplete combustion alarm, etc. These five basic functions are operated by the program of the one-chip microcomputer 17 in the control unit 16.

Among the above-mentioned functions, the function (2) of cutting off gas by judging abnormal use of the gas equipment for a long time (safety use time over cut-off function) is a one-chip microcomputer 17
When the flow rate classification and the cutoff time table corresponding to that flowrate classification are stored in the ROM built in the and the flow rate continues to flow for longer than the cutoff time stored in the flowrate category corresponding to the measured flow rate. The gas is automatically shut off.

[0006]

In the conventional safety meter over-use shutoff function in the gas meter with the automatic shutoff function, the shutoff time is stored in advance in the ROM of the one-chip microcomputer, so that it is installed once in the customer. And cannot be changed. On the other hand, the usage status of gas appliances in consumers varies not only with the seasons but also with the times. In particular, once a gas meter is installed in a customer, it will be used for about 10 years, so the usage status of the gas equipment in the customer may change with the times and may not match the cutoff time initially stored in the ROM, resulting in erroneous cutoff. There is.

[0007] Therefore, an object of the present invention is to provide a shutoff control unit capable of monitoring the gas usage condition according to a judgment criterion that always matches the usage condition of the gas equipment of the consumer due to changes in seasons and times. It is in.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention continuously supplies a gas to a gas device of a certain flow rate section for more than a cutoff determination time set corresponding to the flow rate section. A shutoff control unit having a function of shutting off gas supply when flowing, and having a shutoff determination time table in which a shutoff determination time corresponding to the flow rate category is stored in advance.
OM, a RAM having a duration time table that stores the average value of the continuous use time in the flow rate section measured in a certain period after the operation of the gas equipment, and the gas to the gas equipment in the cutoff determination time table. When the continuous flow exceeds the cutoff determination time, the supply of the gas is cut off, and after the average value of the continuous use time is stored in the continuation time table, it is calculated based on the average value of the continuous use time. The gist of the present invention is to have a control unit that shuts off the gas supply based on the new shutoff determination time.

[0009]

In the above structure, when the gas equipment is initially installed, R
The interruption determination is performed based on the interruption determination time stored in the OM interruption determination time table. The average value of the continuous use time of the gas in the flow rate section is measured in a fixed period (for example, one month) after the operation of the gas device, and the measured data is stored in the continuous time table in the RAM. Then, after the average value of the continuous use times is stored in the continuous time table, the cutoff determination is performed based on the new cutoff determination time obtained based on the average value of the continuous use times. As a result, it becomes possible to monitor the gas usage status based on a determination standard that always matches the usage status of the gas equipment of the consumer due to changes in seasons and times.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. First, the overall configuration of a gas meter with an automatic shutoff function that incorporates a shutoff control unit will be described.

As shown in FIG. 1, a gas meter 218 with an automatic shut-off function has a fault display LED 202 for displaying a reason for shut-off and a shut-off function centered on a one-chip microcomputer 201 as a control means in the shut-off control unit 219. A test switch 203 for performing a test, a pressure sensor 204 for detecting a pressure drop, and a pressure sensor input circuit 20.
5. Seismic detector 206 and seismic detector input circuit 207 for detecting an earthquake, reed switch 208 and flow pulse input circuit 209 for detecting flow rate pulse, shutoff valve 210 for shutting off gas, and one-chip A communication signal I / O for communicating with a center device 220 installed in a gas company or the like using a telephone line through a shutoff signal output circuit 211 that drives a shutoff valve 210 by a shutoff signal from the microcomputer 201 and a T-NCU 216. O circuit 212, HA installed in the house
HA board I / O circuit 213 for communicating with the board 217, battery 214 for supplying power to each circuit, battery 21
4 voltage drop detection circuit 215 for detecting voltage drop
It consists of

The one-chip microcomputer 201 is a ROM 301 for storing a program as shown in FIG.
From an instruction decoder 302 for controlling the I / O circuit, an I / O circuit 303 for outputting a cutoff signal, an arithmetic circuit (ALU) 304 for calculating the gas flow rate, a RAM 305 for storing the calculation result of the gas flow rate, etc. It is configured.

As shown in FIG. 3, the ROM 301 is provided with a cutoff determination time table (ROM table) in which a plurality of flow rate sections and cutoff determination times corresponding to the flow rate sections are stored. Further, in the RAM 305, FIG.
As shown in FIG. 5, a continuation time table (RAM table) for storing the continuation time corresponding to the flow rate classification of the ROM table and its deviation is provided. Next, the operation of the gas meter with the automatic shutoff function configured as described above will be described.

First, the operation immediately after mounting the gas meter will be described. Immediately after the gas meter is installed, the “safety use time over interruption” interruption judgment is performed according to the flow rate classification stored in the ROM 301 in the one-chip microcomputer 201 and the interruption determination time corresponding to the flow rate classification as in the conventional case.

Next, the shutoff control unit 219 is instructed by the center device 220 for a certain period (for example, one month).
The continuous use time of the gas is measured for each flow rate category stored in the ROM 301, the average time and the deviation thereof are calculated, and this is stored in the newly provided continuation time table (FIG. 4) in the RAM 305 when a certain period has elapsed. ..

The one-chip microcomputer 201 has a RAM 3
If the duration and deviation are registered (stored) in the duration table (FIG. 4) in 05, the center device 220
According to the instruction from, the deviation is added to the registered continuation time (average value) as shown in equation (1), and the product is multiplied by a coefficient (for example, 1.2) to "safe use time over cutoff". The cutoff judgment is performed. (Shutdown determination time + deviation) × coefficient (1) When the duration is not registered in the RAM 305, the shutoff determination time table stored in advance in the ROM 301 is used.

Therefore, the "cutoff determination time" stored in advance in the ROM 301 according to the instruction from the center device 220 is changed to the "shutdown determination time" that matches the usage status of the gas equipment of the customer.
Can be changed to

As described above, according to the shutoff control unit of this embodiment, the "shutdown determination time" registered in advance in the ROM 301 is used as the "shutoff determination time" depending on the usage status of the gas equipment of the customer. Since it can be changed to "time", it is possible to prevent erroneous disconnection due to changes in the usage status of gas appliances of consumers.

[0019]

As described above, according to the present invention,
The usage status of the gas equipment (the continuous usage time of the gas in the flow rate category) is measured for a certain period after the gas equipment is operated, and based on the measured data, the cutoff judgment time registered in advance in the ROM is used by the customer. Since it was changed to a new cutoff judgment time that matches the usage status of gas equipment, the usage status of gas should be monitored with a judgment standard that always matches the usage status of gas equipment of consumers due to changes in seasons and times. You can

[Brief description of drawings]

FIG. 1 is a block diagram showing a gas meter with an automatic shutoff function, which incorporates an embodiment of a shutoff control unit according to the present invention.

FIG. 2 is a block diagram showing an internal configuration of the one-chip microcomputer in FIG.

FIG. 3 is a diagram showing an interruption determination time table provided in a ROM in FIG.

FIG. 4 is a diagram showing a duration table provided in a RAM shown in FIG.

FIG. 5 is a configuration diagram showing a conventional gas meter with an automatic shutoff function.

[Explanation of symbols]

 201 one-chip microcomputer (control means) 210 shutoff valve 211 shutoff valve drive circuit 218 gas meter with automatic shutoff function 219 shutoff control unit 301 ROM 305 RAM

Claims (1)

[Claims] 1. A shutoff control unit having a function of shutting off gas supply when a gas to a gas device of a certain flow rate category continuously flows for an interruption determination time set corresponding to the flow rate category. A ROM having a shutoff determination time table in which the shutoff determination time corresponding to the flow rate category is stored in advance, and an average value of continuous use time in the flow rate category measured in a certain period after the gas appliance is operated. And a RAM having a continuation time table for storing the gas, and interrupting the supply of the gas to the gas device when the gas continuously flows beyond the interruption judgment time in the interruption judgment time table, and the continuation time table. After the average value of continuous use time is stored in, the control to cut off the gas supply based on the new cutoff determination time obtained based on the average value of the continuous use time. Cut-off control unit, characterized in that it comprises a means.