Credit the inventors of the
NexxtDrive CVT concept with some original thinking, as it’s a transmission not quite like anything we’ve seen
before. Using a generator and motor to create a controlled secondary energy path, the NexxDrive directs engine
torque through three epicyclical gear sets to effectively create a continuously-variable gear ratio.
Despite the use of the motor and generator, the system isn’t just for use with hybrids – although it’s said to
lend itself nicely to that application. The energy developed with the generator system can be directly fed back
into the motor, or stored in a battery pack for future use. With a lack of clutches, pulleys, belts, and
chains, the current design is said to be suitable for engines up to 270 HP, and there doesn’t appear to be any issues
with scaling the technology for larger applications. The layout of this gearbox looks to be perfectly suited to
longitudinal engine orientations.
Yes, there are some similarities here to the planetary-based Toyota
Hybrid Synergy Drive system, and hopefully NexxtDrive’s patent lawyers have given this the go-ahead so that we can
avoid future posts on intellectual property litigation.