Dual Ratio Constant Mesh Gearbox

摘要

A dual ratio constant mesh gearbox is provided that is suitable for use with an automobile, and particularly well-suited for an electric vehicle. The gearbox, which may be configured either as a manual or automatic gearbox, utilizes a planetary gear set and a pair of clutches to shift between under drive and direct drive modes.

主权项

1. A dual ratio constant mesh gearbox, comprising:
a housing; an input drive shaft at least partially contained within said housing, wherein said input drive shaft is coupled to a vehicle propulsion electric motor; a sun gear rigidly coupled to said input drive shaft; a ring gear; a set of planetary gears interposed between said sun gear and said ring gear, wherein said set of planetary gears are in constant mesh with said sun gear and said ring gear; a planetary gear carrier coupled to said set of planetary gears and to an output drive shaft, wherein said output drive shaft is at least partially contained within said housing; a sprag clutch assembly contained within said housing, wherein said sprag clutch assembly permits rotation of said ring gear in a first direction and prevents rotation of said ring gear in a second direction; and a second clutch assembly separate and independent of said sprag clutch assembly, wherein engaging said second clutch assembly locks said ring gear to said sun gear, and wherein disengaging said second clutch assembly unlocks said ring gear from said sun gear.