| 摘要 |
PURPOSE:To firmly prevent explosion and the like which occurs owing to discharge of unburnt gas by stopping discharge of gas before the density of gas reaches a dangerous degree in case the unburnt gas is discharged accidently. CONSTITUTION:When a gas appliance is operated, gas enters a gas meter 3 through a gas supply pipe 1 to operate the gas meter. The operation of the meter 3 rotates a rotary shaft 6, outputting signals from a flow rate meter 6 one pulse signal every rotation of the shaft 6. The output signals are received in a control apparatus 9 which makes count and calculation of an average flow rate every one minite or so. The average flow rate is traced to see how long the rate is kept constant, the respective flow rate of respective gas appliance which constitutes the traced average flow rate is compared with the judging standard of a program previously stored in the control apparatus 9 or a duration time assigned to the specific class of flow rate, and the appropriate signal is transmitted. |
