Patent attributes
According to the present apparatus, there are provided throttle valves 20 that are disposed in intake passages, a throttle shaft 30 that supports the throttle valves 20 to be opened/closed, drive means 40 that rotatably drives the throttle shaft 30, and a torsion type return spring 50 that deforms in a manner interlocked with the turn of the throttle shaft 30, and returns the throttle valves 20 to a rest position on a close side, and a deformation force transmission mechanism 60 including a speed reducing gear 62 is provided to cause a torsion deformation on the return spring 50 within an angular range smaller than the rotation angle range of the throttle shaft 30. As a result, the maximum energizing force is reduced. Consequently, the maximum energizing force of the return spring is reduced on the throttle apparatus where the throttle valves are returned to the rest position by the return spring.
