Throttle device for internal combustion engine

Abstract

In an initial opening degree setting mechanism which keeps an initial opening degree of a throttle valve (24) larger than that of a fully closed position thereof when no current is supplied to a motor (12) for driving a throttle shaft (18) for the throttle valve (24), a throttle lever (3) and a sleeve (45) are inserted into the throttle shaft (18) and secured thereto and a sleeve (42) integrated with a return lever (2) is fitted over the sleeve (45) so as to permit a relative rotational mevement with respect to the sleeve (45). The sleeve (42) is urged by a return spring (4) in the direction of closing the throttle valve (24) upto the position of the initial opening degree. With the urging force the return lever (2) is placed to be engageable with the throttle lever (3). The throttle shaft (18) is applied of a valve opening force by a spring for keeping the initial opening degree of the throttle valve (24) near the fully closed position thereof, thereby parts belonging to the throttle valve initial opening degree setting mechanism are collectively and rationally arranged, a driving load of the throttle actuator motor (12) is reduced and a throttle valve control operation is stabilized.

Dependencies are inferred from the claim text.