Fluid flow measuring apparatus

Claim 1

APPARATUS FOR DETECTING THE DIRECTION AND MAGNITUDE OF FLUID FLOW WITH RESPECT TO A GIVEN AXIS OF FLOW COMPRISING, A CONDUIT FOR DEFINING SAID AXIS OF FLOW, MEANS FORMING A FLUID FLOW OBSTACLE PLACED WITHIN SAID CONDUIT ON SAID AXIS OF FLOW AND PRESENTING LIKE CONTOURS TO FLOW ABOUT SAID OBSTACLE IN EITHER DIRECTION ALONG SAID AXIS OF FLOW, AT LEAST TWO TEMPERATURE SENSING ELEMENTS, MEANS FOR TENDING TO MAINTAIN THE TEMPERATURE OF EACH ELEMENT AT A PREDETERMINED LEVEL, AND MEANS POSITIONING SAID ELEMENTS SYMMETRICALLY WITH RESPECT TO SAID OBSTACLE MEANS AND SAID AXIS OF FLOW SO THAT FOR FLOW ALONG SAID AXIS IN ONE DIRECTION ONE ELEMENT WILL BE AT A TEMPERATURE GREATER THAN THE OTHER ELEMENT, DUE TO DIFFERENT AMOUNT OF HEAT TRANSFER BETWEEN EACH ELEMENT AND THE FLUID SURROUNDING IT, AND VICE-VERSA FOR FLOW ALONG THE AXIS IN THE OPPOSITE DIRECTION, AND WHEREIN THE OBSTACLE IS A FLAT PLATE MEMBER INCLINED TO THE AXIS OF THE FLOW AND WHICH COMPRISES TWO OF SAID ELEMENTS POSITIONED ON OPPOSITE SIDES OF SAID PLATE.