Electronic fuel control systems with nonlinearizing circuit means interconnecting the pressure transducer with the main computation means

Claim 1

An engine control circuit for providing an output signal with a value indicative of the fuel requirement of an inteRnal combustion engine having an air intake manifold and a fuel requirement that increases nonlinearly and monotonically in response to decreasing air pressure in the manifold, said control circuit comprising: an energy receiving input terminal; a ground terminal; an output terminal; means defining an electrically conductive path between said input and ground terminals and including a first electrically resistive element having an electrical resistance that varies linearly along said element; a contact member movable along said resistive element in response to changing air pressure within the intake manifold, said contact member connecting said resistive element with said output terminal to provide an output signal at said output terminal; and means defining a second electrically conductive path connecting said contact member with said ground terminal, said second path including a passive electrical resistance in parallel with one portion of said first resistive element and in series with another portion of said first resistive element, the relative sizes of said portions of said first resistive element being varied by motion of said contact member along said first resistive element to cause that output signal to vary nonlinearly and in accordance with engine fuel requirement.