Manifold pressure controller fuel limiter

Claim 1

For scheduling and limiting the flow of fuel to an internal combustion engine having a throttle, a manifold and a lubricating system in which air and oil pressures build up on starting of the engine, the combination of a power actuator coupled to said throttle and selectively energizable to move the throttle in opposite directions to increase and decrease the fuel supply to said engine, a stop limiting the fuel-increasing movement of said throttle and movable away from a starting position to change the limit to which said throttle may be moved by said actuator, said stop, when in starting position, establishing a fuel admission rate adequate for starting the engine in the absence of manifold pressure in excess of atmospheric pressure, a power operator activated in response to a combined build-up by the engine after starting of air pressure in said manifold and oil pressure in said syStem and acting to move said stop away from said starting position, said operator comprising a fluid servo having a piston slidable in a cylinder and moving said stop away from said starting position by pressure fluid admitted to one end of the cylinder by the action of valve means controlled jointly by the build-up of pressures in said lubricating system and said manifold following starting of the engine, means exerting on said piston a force continuously biasing said stop toward said starting position, a controller selectively operable to govern the energization of said actuator, a motion-transmitting connection coupling said throttle to said controller and acting to adjust the fuel supply setting thereof, if above the prevailing limit determined by said stop, for a lesser supply rate, and said valve means being responsive to a decrease in said lubricating oil pressure upn interruption of said fuel supply and stopping of the engine and enabling said biasing means to move said stop back to said starting position.