MULTI-MODE TRANSMISSION FOR VEHICLE POWERTRAIN SYSTEM

摘要

A torque transmission device for a powertrain system includes a continuously variable unit (CVU) of a continuously variable transmission (CVT) arranged in parallel with a fixed-gear-ratio transmission. The fixed-gear-ratio transmission includes first and second planetary gear sets and a plurality of transmission clutches, wherein the first and second planetary gear sets are arranged to transfer torque between an input member and an output member in one of first and second fixed-gear-ratio modes by selectively activating the transmission clutches. The torque transmission device operates in a first fixed overdrive input/output speed ratio when the CVU input clutch is deactivated and a first set of two of the transmission clutches is activated. The torque transmission device operates in a second fixed overdrive input/output speed ratio when the CVU input clutch is deactivated and a second set of two of the transmission clutches is activated.

主权项

1. A torque transmission device for a powertrain system, comprising:
a continuously variable unit (CVU) arranged in parallel with a fixed-gear-ratio transmission to transfer torque between a transmission input member and a transmission output member; the transmission input member selectively rotatably coupled to an input member of the CVU by activating a CVU input clutch; the transmission output member rotatably coupled to a CVU output member; the fixed-gear-ratio transmission including first and second planetary gear sets and a plurality of transmission clutches, wherein the first and second planetary gear sets are arranged to transfer torque between the transmission input member and the transmission output member in one of first and second fixed-gear-ratio modes by selectively activating the transmission clutches; the first and second planetary gear sets each including a plurality of meshingly engaged gear members including a ring gear, a plurality of planet gears coupled to a carrier and a sun gear, wherein each of the gear members is a node; the transmission input member rotatably coupled to one of the nodes of one of the first planetary gear set and the second planetary gear set and the transmission output member rotatably coupled to another of the nodes of one of the first planetary gear set and the second planetary gear set; the torque transmission device operating in a continuously variable mode when the CVU input clutch is activated; the torque transmission device operating in the first fixed-gear-ratio modes including a first fixed overdrive input/output speed ratio when the CVU input clutch is deactivated and a first set of two of the transmission clutches is activated; and the torque transmission device operating in the second fixed-gear-ratio modes including a second fixed overdrive input/output speed ratio when the CVU input clutch is deactivated and a second set of two of the transmission clutches is activated.