Patent ID: 7467547
Filing Date: 2008-12-23
Classification: G01F,G01N

Abstract:
1. A fluid-measuring device using a flow sensor said flow sensor including: a heater for heating a fluid flowing in a flow path and generating a specific temperature profile; an upstream side temperature sensor for detecting temperature of the fluid at the upstream of the flow path with respect to the heater, and outputting an upstream side temperature signal; a downstream side temperature sensor for detecting the temperature of the fluid at the downstream of the flow path with respect to the heater, and outputting a downstream side temperature signal; and lateral side temperature sensors disposed at a direction substantially perpendicular to a flow of the fluid for detecting the temperature of the fluid and outputting lateral side temperature signals, said fluid-measuring device comprising: a heater controller for intermittently driving the heater for a measuring interval from a start of measuring the flow rate to the end of measuring; a lateral side temperature signal upon non-driving receiving member for receiving a lateral side temperature signal outputted from the lateral side temperature sensor whenever the heater stops driving by a control of the heater controller as a lateral side temperature signal upon non-driving; a lateral side temperature signal upon driving receiving member for receiving a lateral side temperature signal outputted from the lateral side temperature sensor in response to the driving of the heater controlled by the heater controller after the lateral side temperature signal upon non-driving receiving member receives the lateral side temperature signal upon non-driving as a lateral side temperature signal upon driving corresponding to the lateral side temperature signal upon non-driving received by the lateral side temperature signal upon non-driving receiving member; a physical properties data detecting member for detecting physical properties data indicating physical properties of the fluid corresponding to the thermal profile in the substantially perpendicular direction on the basis of the lateral side temperature signal upon non-driving received by the lateral side temperature signal upon non-driving receiving member and the lateral side temperature signal upon driving received by the lateral side temperature signal upon driving receiving member; a temperature signal receiving member for receiving the upstream side temperature signal outputted by the upstream side temperature sensor and the downstream side temperature signal outputted by the downstream side temperature sensor corresponding to the lateral side temperature signal upon driving received by the lateral side temperature signal upon driving receiving member when the heater is driven by a control of the heater controller; a correcting member for correcting the upstream and downstream side temperature signals received by the temperature signal receiving member on the basis of the physical properties data detected by the physical properties data detecting member; and a flow rate calculating member for detecting the temperature profile varied corresponding to the velocity of the fluid on the basis of the upstream and downstream side temperature signals corrected by the correcting member and calculating the flow rate of the fluid on the basis of the detected temperature profile.