Patent ID: 7231903
Filing Date: 2007-06-19
Classification: F02D,F16N

Abstract:
1. A throttle device for an internal combustion engine comprising an electric drive actuator for opening and closing a throttle valve to control an intake air flow rate of the internal combustion engine, a default opening degree setting mechanism for keeping an opening degree of said throttle valve at a default opening degree larger than a full close position when said electric drive actuator is not energized, a gear case for containing a gear mechanism to transmit power of said electric drive actuator to a throttle valve shaft is arranged on an outer wall of a throttle body, said throttle valve shaft being provided between said gear mechanism and a wall portion of said throttle body, a returning spring providing a spring force on said throttle valve in a closing direction and a default spring providing a spring force on said throttle valve in a direction toward a side of the default opening degree seen from the full close position of the throttle valve have diameters different from each other, a default lever provided around said throttle valve shaft so as to be able to rotate respectively to said throttle valve shaft, said default spring provided between said default lever and said gear mechanism, and said returning spring is provided between said default lever and said wall portion of said throttle valve shaft wherein one portion of said default spring is overlapped to one portion of said returning spring, and said default lever is arranged between the overlapped portion of both springs.