MICRO-FLOW METER AND MICRO-FLOW MEASURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a micro-flow meter which is inexpensive and highly accurate with a simple structure, whose necessity of maintenance is low, and moreover which is capable of comparatively-extensive micro-flow measurement, and to provide a micro-flow measuring method.;SOLUTION: The micro-flow meter includes: a channel for making a fluid pass through; a heater 4 for heating the fluid in the channel; a temperature detecting section 5 for detecting the temperatures of the fluid before and after being heated on the more downstream side than the heater 4; and an information processor 54 for acquiring a flow rate from the detected temperatures obtained by the temperature detecting section 5. The information processor 54 includes a memory device for storing beforehand a calibration function representing the relation between the amount of temperature increase of the fluid and its flow rate, and an arithmetic processor for acquiring the amount of temperature increase from the detected temperatures obtained by the temperature detecting section 5, and acquiring a flow rate corresponding to this amount of temperature increase from the calibration function. The calibration function has a first region where the relation between the amount of temperature increase and the flow rate is a positive linear relation, and a second region where the relation between the amount of temperature increase and the flow rate is a negative linear relation on the larger flow-rate side than the first region.;COPYRIGHT: (C)2010,JPO&INPIT