A speed increaser includes an annular peripheral wall rotatable with a rotation of the low-speed shaft, a high-speed shaft disposed within the peripheral wall and having a rotation axis extending in the same direction as that of the peripheral wall, and three rollers disposed within the peripheral wall and in contact with both the peripheral wall and the high-speed shaft. The three rollers are disposed at different positions along the rotation axis of the high-speed shaft with rotation axes of the three rollers extending in the same direction as the rotation axis of the high-speed shaft, and the rotation axes of the three rollers are spaced in a circumferential direction of the high-speed shaft. The three rollers are disposed so that at least part of contact areas between the high-speed shaft and the rollers is free from overlapping with each other along the rotation axis of the high-speed shaft.

A high speed ratio drive system is formed of planet rollers, each having varying diameter, an outer fixed ring in contact with one diameter of the planet rollers, and an outer drive ring in contact with another diameter of the planet rollers. An inner drive element is provided by a sun drive roller in contact with the planet rollers or by a planet carrier. Preferably the system has an axial reflective symmetry minimizing twisting forces on the planet rollers.

Disclosed is a spring for preload in a planetary traction drive designed for a driven turbocharger on an engine. The ring roller of the planetary traction drive has two parts with a spring between the two parts for generating a preload force on the ring roller assembly of the planetary traction drive. The spring provides a spreading force on the ring roller, and allows for setting a desired preload force on the traction surfaces of the traction drive during assembly and operation, even with variations in manufacturing of the different parts of the traction drive.

Disclosed is an adjustable ring shim for a planetary traction drive designed for a driven turbocharger on an engine. The adjustable ring shim has two parts that interface through a ramp feature to provide an ability to vary the overall width of the ring roller assembly of the planetary traction drive. This adjustability in the width of the ring roller allows for setting a desired preload force on the traction surfaces of the traction drive during assembly, even with variation in manufacturing of the different parts of the traction drive.

A planetary gearbox with two rows of planets between an inner race and a coaxial outer race. An input gear may also mesh with the inner planets or the outer planets. To avoid unmeshing of the gears due to twisting from the applied torque, a camming effect may be used in which applied torque generates a radial preload. The gears that mesh with the input gear may do so at portions of the gears that also mesh with a corresponding one of the inner or outer race. The planets may be geared with axial portions with different helix angle. The inner race or outer race may be formed of two components geared with different helix angle to mesh with the different axial portions of the planets. By using these different components, assembly is eased as the components can be slid onto the planets axially.

A planetary gearbox with two rows of planets between an inner race and a coaxial outer race. An input gear may also mesh with the inner planets or the outer planets. To avoid unmeshing of the gears due to twisting from the applied torque, a camming effect may be used in which applied torque generates a radial preload. The gears that mesh with the input gear may do so at portions of the gears that also mesh with a corresponding one of the inner or outer race. The planets may be geared with axial portions with different helix angle. The inner race or outer race may be formed of two components geared with different helix angle to mesh with the different axial portions of the planets. By using these different components, assembly is eased as the components can be slid onto the planets axially.

Disclosed is a spring for preload in a planetary traction drive designed for a driven turbocharger on an engine. The ring roller of the planetary traction drive has two parts with a spring between the two parts for generating a preload force on the ring roller assembly of the planetary traction drive. The spring provides a spreading force on the ring roller, and allows for setting a desired preload force on the traction surfaces of the traction drive during assembly and operation, even with variations in manufacturing of the different parts of the traction drive.

A gearbox is disclosed. The gearbox can have planetary gears. Each planetary gear can revolve around a rotational center of itself while concurrently revolving around a rotational center of the gear system as a whole. The gearbox can be used to deliver rotational output energy at a right (or other angle) from the direction of a received input energy.

A gearbox is disclosed. The gearbox can have planetary gears. Each planetary gear can revolve around a rotational center of itself while concurrently revolving around a rotational center of the gear system as a whole. The gearbox can be used to deliver rotational output energy at a right (or other angle) from the direction of a received input energy.

A method of controlling a continuously variable electric drivetrain (CVED) including a high ratio traction drive transmission and at least one of a first motor-generator and a second motor-generator is disclosed. The method includes the steps of receiving an output speed, determining a kinematic output speed, and determining a slip state of the high ratio traction drive transmission based on a comparison of the output speed to the kinematic output speed.