Fluid flow measuring apparatus

The apparatus for measuring the velocity and direction of a fluid moving in a fluid flow path comprising:

• housing means having a fluid flow path, side wall means having a plurality of rows of openings open to the outside of the housing means, and annular passage means in communication with said plurality of rows of openings and the fluid flow path, ionizing means mounted on the housing means and located adjacent the fluid flow path for producing ions, ion collecting means mounted on the housing means and located adjacent the fluid flow path and generally opposite the ionizing means, said ion collecting means having more than two separated electrical conductor members, each member having angularly related side edges, the side edges of adjacent members being spaced from each other, means for maintaining an electrical potential between said ionizing means and ion collecting means whereby ions migrate from the ionizing means and impinge on the conductor members producing a current in each conductor member, said fluid moving in the fluid flow path deflecting said ions in the direction of movement of the fluid and in an amount proportional to the velocity of the fluid thereby producing different currents in at least some of the conductor members, and amplifier means electrically connected to each conductor member, said amplifier means having output signals directly proportional to the difference in the currents in selected conductor members, said signals providing information as to the velocity and direction of the moving fluid.