Patent ID: 8099248

Claim:
A flow rate measuring device comprising: a flow rate measurement unit configured to measure a gas flow rate flowing in a flow channel; an appliance registering unit configured to store at least first gas flow rate variation profiles exhibited by a first gas appliance and a second gas appliance, respectively, upon activation thereof, which are coupled to the flow channel, and second gas flow rate variation profiles exhibited by the first gas appliance and the second gas appliance, respectively, under control peculiar thereto; a calculating unit configured to determine a differential value of flow rate value data outputted from the flow rate measurement unit; a determining unit configured to compare the differential value determined by the calculating unit with a preset variation determination value to thereby determine that a state of at least one of the first gas appliance and the second gas appliance has varied when the differential value is larger than the preset variation determination value; a first appliance identifying unit configured to compare a gas flow rate variation profile measured by the flow rate measurement unit with the first gas flow rate variation profiles stored in the appliance registering unit to thereby identify the first gas appliance and the second gas appliance that are activated; and a second appliance identifying unit, wherein when the calculating unit calculates a differential value based on variation of the gas flow rate measured by the flow rate measurement unit and the determining unit detects a stop of one of the first gas appliance and the second gas appliance based on the calculated differential value, the second appliance identifying unit compares a gas flow rate variation profile exhibited after the stop is detected with the second gas flow rate variation profiles stored in the appliance registering unit to thereby identify a gas appliance in use and a gas appliance having stopped of the gas appliances that are determined to be activated by the first appliance identifying unit.