APPARECCHIO DI RILEVAMENTO DELLA VELOCITA DI UN FLUSSO DI FLUIDO AD ALTA TEMPERATURA

摘要

A speed detection apparatus intended to be placed in a borehole containing high temperature flowing fluid consists of an elongated casing with a rotary shaft having a helical rotary blade in the casing. Secured to the rotary shaft is a sensor control rotor with a plurality of metal targets on the periphery. Opposed to these targets is an eddy currents displacement transducer with electric circuitry including a coil. The displacement of the targets due to fluid flow causes impedance change in the coil which produces an electrical signal proportional to the rate of flow.