Flow rate measuring device

摘要

A flow rate measuring device simplifies calculation, reduces memory required for calculation, absorbs variations due to manual operation and, depending on the state of ignition, improves the accuracy of appliance identification by extracting features of appliances. The flow rate measuring device includes: a difference value conversion unit that converts into codes difference values of the flow rate measured at constant time intervals by an ultrasonic flowmeter; an appliance feature extraction unit creates an appliance feature code string indicating a feature of each appliance by, for example, making comparison and judgment using a third last code, a second last code, a last code and a current code of the codes obtained at constant time intervals, and by performing code deletion; and an identification unit performs appliance identification by comparing the appliance feature code string with an appliance inherent feature code string indicating the feature code string inherent in each appliance.

主权项

1. A flow rate measuring device comprising:
a computer processor; a flow rate measurement device to measure the flow rate of fluid flowing through a flow passage at constant time intervals; a calculation unit executable by the computer processor to calculate difference values of the flow rate measured by the flow rate measurement device at the constant time intervals; a flow rate classification table in which classifications of a plurality of difference values, depending on magnitudes of the difference values, are associated with codes representing the classifications; a difference value conversion unit executable by the computer processor to convert the difference values calculated by the calculation unit into codes on the basis of the flow rate classification table; an appliance feature extraction unit executable by the computer processor to generate an appliance feature code string indicating the feature of an appliance from the codes obtained at constant time intervals by the difference value conversion unit; and an appliance identification unit executable by the computer processor to perform appliance identification by comparison of the appliance feature code string with a predetermined appliance inherent feature code string indicating the feature code string inherent in each appliance, wherein in response to a last code of the codes obtained by execution of the difference value conversion unit being larger than a second to last code and the last code being larger than a current code, or in the case that the last code is smaller than the second to last code and the last code is smaller than the current code, the appliance feature extraction unit executable by the computer processor to store the current code in the appliance feature code string; and in all other cases, the extraction unit executable by the computer processor to overwrite the current code onto the last code stored in the appliance feature code string.