High speed and continuously variable traction drive

A method of transferring rotational mechanical energy between a shaft and a ring roller comprising:

• providing a shaft that has a central portion, said central portion having a shaft traction surface;
• placing a plurality of planet roller traction surfaces of a plurality of planet rollers in contact with said shaft traction surface so that a plurality of first traction interfaces are created between said plurality of planet roller traction surfaces and said shaft traction surface;
• placing a ring roller in contact with said plurality of planetary rollers so that a plurality of second traction interfaces are created between said plurality of planet rollers and said ring roller;
• mounting said plurality of planetary rollers on a planet carrier that rotates in a direction opposite to said ring roller.

A continuously variable traction drive comprising:

• a first race that is rotationally coupled to a shaft;
• a second race that is fixed with respect to said continuously variable traction drive;
• a third race that is rotationally coupled to said shaft and mounted in said continuously variable traction drive to allow lateral translation of said third race with respect to said first race and said second race;
• a fourth race that is rotationally coupled to a gear, said fourth race mounted in said continuously variable traction drive to allow lateral translation of said fourth race by an amount and in a direction that is substantially equal to said lateral translation of said third race;
• a plurality of traction ball bearings disposed between said first race, said second race, said third race and said fourth race.

A method of transferring rotational mechanical energy between a first shaft and a second shaft in a substantially continuously variable manner in a continuously variable traction drive comprising:

• rotationally coupling a first race to said first shaft, said first race having a first curved surface;
• fixing a second race to said continuously variable traction drive, said second race having a second curved surface;
• rotationally coupling a third race to said third shaft in a manner that allows lateral translation of said third race with respect to said first race and said second race, said third race having a third curved surface;
• rotationally coupling a fourth race to said second shaft in a manner that allows lateral translation of said fourth race by an amount and in a direction that is substantially equal to said lateral translation of said third race, said fourth race having a fourth curved surface;
• clamping a plurality of ball bearings between said first race, said second race, said third race and said fourth race that have a spherical surface that has a radius of curvature that is less than radii of curvature of said first curved surface, said second curved surface, said third curved surface and said fourth curved surface, so that said lateral translation of said third race and said fourth race changes contact locations of said plurality of ball bearings on said first race, said second race, said third race and said fourth race, which changes rotational speed of said ball bearings at a contact point between said plurality of ball bearings and said fourth race, which varies a rotational speed of said second shift with respect to said first shaft.