Variable and differential output drive system

A drive system with the capability for providing continuously variable and differential outputs, the drive system comprising:

• a power source system including a combustion engine coupled to an electric generator;
• first, second, and third electric drive units coupled to the electric generator;
• first and second planetary gear assemblies, each planetary gear assembly including a sun gear, a ring gear, a carrier, and a plurality of planetary elements;
• the first electric drive unit mechanically coupled via a first gear to the ring gear of the first planetary gear assembly;
• the second electric drive unit mechanically coupled via a second gear to the ring gear of the second planetary gear assembly;
• the third electric drive unit mechanically coupled to the sun gear of the first planetary gear assembly and to the sun gear of the second planetary gear assembly;
• and
• first and second output shafts coupled, respectively, to the carrier of the first planetary gear assembly and to the carrier of the second planetary gear assembly.

A drive system with the capability for providing continuously variable and differential outputs, the drive system comprising:

• a power source system including a combustion engine coupled to an electric generator;
• first, second, and third electric drive units coupled to the electric generator;
• first and second planetary gear assemblies, each planetary gear assembly including a sun gear, a ring gear, a carrier, and a plurality of planetary elements;
• the first electric drive unit coupled to the sun gear of the first planetary gear assembly;
• the second electric drive unit coupled to the sun gear of the second planetary gear assembly;
• the third electric drive unit coupled to the ring gear of the first planetary gear assembly and to the ring gear of the second planetary gear assembly;
• and
• first and second output shafts coupled, respectively, to the carrier of the first planetary gear assembly and to the carrier of the second planetary gear assembly.

A method for providing continuously variable and differential outputs to first and second output shafts coupled, respectively, to first and second planetary gear assemblies, the method comprising:

• providing a first variable drive unit coupled to the first planetary gear assembly;
• providing a second variable drive unit coupled to the second planetary gear assembly;
• providing a third variable drive unit coupled to both the first and the second planetary gear assemblies;
• operating the first drive unit to drive the first output shaft;
• operating the second drive unit to drive the second output shaft;
• and
• operating the third drive unit to drive the first and the second output shafts.