| 摘要 |
PROBLEM TO BE SOLVED: To provide a flow-rate measuring apparatus by which pulses according to a passage volume can be output without making a sampling cycle short and whose power consumption is reduced and to provide an electronic gas meter whose power consumption is reduced and which is provided with a flow- rate measuring part and a security logic part. SOLUTION: A flow-rate measuring means 14a-1 intermittently measures a physical quantity which is changed according to the flow velocity of a gas, it finds the flow velocity of the gas, it finds an instantaneous flow rate on the basis of the flow velocity and on the basis of the cross-sectional area of a flow passage, and it finds a passage volume by multiplying the instantaneous flow velocity by the intermittent time. A passage-volume storage means 14c-1 integrates the passage volume so as to be stored. An output-pulse-number calculation means 14a-2 divides the stored passage volume by a unit passage volume so as to calculate the number of pulses to be output. A pulse output means 14a-3 outputs the calculated number of pulses in a prescribed width until a next sampling cycle is started at a predetermined interval. In a security monitoring means 20, a processing operation which is used to detect the abnormality of a gas flow is performed in units of a sampling cycle.
|
