Patent ID: 7055498

Claim:
A throttle assembly comprising a throttle body and, as components mounted to the throttle body, a throttle valve for controlling the flow rate of intake air in an internal combustion engine, an electrically-driven actuator for actuating the throttle valve, a reduction gear mechanism for the actuator, and a sensor for detecting the degree of opening of the throttle valve, wherein one end of a throttle valve shaft is projected outwards from a side wall of the throttle body, said reduction gear mechanism and said sensor are disposed on a side face of the throttle body on the projecting side of said throttle valve shaft, a bearing which supports one side shaft-part close to the projecting part of the throttle valve shaft, out of bearings which support the throttle valve shaft, is a ball bearing, a bearing, which supports the other side shaft-part opposite to the projecting part of the throttle valve is a plain bearing, a cap, and one end of the plain bearing is covered with a gear of the reduction gear mechanism is fixed on the projecting part of the throttle valve shaft, a coil spring arrangement having a return spring element and a default spring element for the throttle valve is provided around a boss for the ball bearing and a part of the throttle shaft, and one end of the coil spring arrangement is operatively joined to the throttle body, and the other end thereof is joined to the throttle valve.