Throttle apparatus for an internal combustion engine

摘要

A returning spring 7 of the electronic control throttle and a default spring 8 for securing an initial opening degree (default opening degree) of the throttle valve 3 have diameters different from each other, and both of the springs 7, 8 are held around a shaft of the throttle valve shaft 3 and arranged between a gear 43 attached to the throttle valve shaft 3 and a wall portion of the throttle body 100. A shaft supporting gap of the throttle valve shaft 3 is filled with an air leak preventing material, and a minimum opening degree of the throttle valve is set to a value larger than an amount of overshoot of the throttle valve occurring when opening degree of the throttle valve is changed from a maximum opening degree of the throttle valve to the minimum opening degree.