System for measuring fluid flow


A system for measuring fluid flow, e.g. in an air duct 10, comprises a first sensor 16 adapted to produce an output signal dependent on the temperature of the fluid, and a second sensor 18 which is disposed in the flow path of the fluid. The second sensor 18 includes a temperature responsive integrated circuit device 23 and a heater 24 located adjacent thereto, and produces an output signal indicative of the resultant temperature due to the heating effect of the heater and the cooling effect of the flow of fluid past the second sensor. The signals from the first and second sensors are processed to produce an output indicative of the rate of fluid flow. As shown the sensor 18 comprises an aerodynamically shaped pod 22 containing paste 23 to provide thermal coupling between the heater and temperature responsive device. The pod is mounted on a transverse strut 17 attached to a frame 13 intended to be bolted between two duct sections. A display 20 shows both temperature in the duct and flow rate. <IMAGE>




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Cited By (6)

    Publication numberPublication dateAssigneeTitle
    EP-0606983-A2July 20, 1994Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.Heating resistor type air flow meter
    EP-0606983-A3August 30, 1995Hitachi Ltd, Hitachi Automotive EngHeizwiderstand-Luftdurchflussmesser.
    US-5440924-AAugust 15, 1995Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.Heating resistor type air flow meter with separate/processing unit
    WO-0106215-A1January 25, 2001Robert Bosch GmbhDispositif de traitement analogique ou numerique de signaux
    WO-9601982-A2January 25, 1996Bear Medical Systems, Inc.Systeme de detection de flux
    WO-9601982-A3February 29, 1996Bear Med Syst IncFlow sensor system