US Patent 7490590 Electronic throttle

A throttle having: a housing having an airflow passage therein; a throttle plate rotatably mounted to the housing and disposed within the passage; a motor disposed outside the passage for rotating the throttle plate within the passage between an open position and a closed position in accordance with demanded torque signals; a spring coupled to the throttle plate for urging the throttle plate to a closed position in the absence of a demanded torque signal; and, an actuator assembly operative to place a stop, disposed outside the passage, in a position to limit rotation of the throttle plate to a predetermined minimum closed position in the absence of a demanded torque signal and for removing the stop when the motor receives a demanded torque signal.