Throttle body default actuation

摘要

The air control valve comprises a housing (12) having an air intake passage or throttle bore (14) extending through it. The bore conducts air to the intake system of the IC engine. The throttle valve includes a throttle plate (18) attached to a shaft (20), and is rotatably mounted within the bore and rotates about an axis, in the range of min. and max. air flow positions. Intermediate of the range is a default position which relates to a predetermined positive air flow, allowing continuous engine operation, should the actuating mechanism used to position the throttle become inoperative. A spring is used to bias the valve to the default position. The valve actuating mechanism includes an electronic actuator (26) operably connected to the throttle shaft of the valve. The actuator drives the valve based on operational input, positioning the valve between the min. and max. air flow positions.