Transmission throttle valve modulator responsive to both positive manifold pressure and negative manifold pressure

摘要

A pneumatic throttle valve actuator for an automatic power transmission mechanism for use with a supercharged or turbocharged internal combustion engine wherein the relationship between manifold pressure and actuator force is changed when the engine manifold pressure changes from a positive pressure to a negative pressure or vice-versa. A correct shift point signal and a correct pressure regulator output thus are maintained regardless of whether the turbocharger or supercharger is active or inactive.