| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas meter which can obtain a proper precision and precisely detect gas leakage by restraining the change of a measured value especially in fine flow rate level (gas leakage detecting level), in a gas meter using a principle of measuring instantaneous flow rate. SOLUTION: When a measured instantaneous flow rate is at least the minimum flow rate wherein precision can be ensured (step S3, YES), result processed by a low-pass filter having a small time constant is outputted as a measured result (step S4). In the other case, i.e., when a measured instantaneous flow rate is at the minimum flow rate level, processing by a low-pass filter having a large time constant is performed (step S5). Basically, when the result is equal to or greater than a leakage detecting flow rate (step S8, YES), the result processed by the low-pass filter having a large time constant is outputted as a measured result (step S10). When it is decided that a rapid change in the flow rate is generated in practical use (step S6, YES), the result processed by the low-pass filter having a small time constant is outputted as a measured result (step S7).
|
