In part, skew limiter for a toric-drive CVT embodiments are disclosed. A skew limiter may include a shaped piece that limits the skew angle to a known angle notwithstanding the tilt angle of the rollers.

A direct shift continuously variable transmission for a vehicle engine includes a variator having a toroidal cavity; a plurality of traction roller rotatably and radially located within the toroidal cavity; an input shaft rotatably disposed within the variator, the input shaft being adapted to receive a torque from the vehicle engine; an input disk coaxially connected to the input shaft and frictionally contacting the traction roller to provide a rotational force to the traction roller; an output disk opposed to the input disk and frictionally contacting the traction roller, the output disk being annularly rotatable by receiving the rotational force from the traction roller; and an output shaft coaxially connected to the output disk and receiving the rotational force from the output disk.

A direct shift continuously variable transmission for a vehicle engine includes a variator having a toroidal cavity; a plurality of traction roller rotatably and radially located within the toroidal cavity; an input shaft rotatably disposed within the variator, the input shaft being adapted to receive a torque from the vehicle engine; an input disk coaxially connected to the input shaft and frictionally contacting the traction roller to provide a rotational force to the traction roller; an output disk opposed to the input disk and frictionally contacting the traction roller, the output disk being annularly rotatable by receiving the rotational force from the traction roller; and an output shaft coaxially connected to the output disk and receiving the rotational force from the output disk.

One aspect of an electric actuator of the present invention includes: a motor having a motor shaft rotatable about a motor axis; a transmission mechanism coupled to one side in the axial direction of the motor shaft; an output shaft extending in the axial direction of the motor shaft and to which rotation of the motor shaft is transmitted via the transmission mechanism; and a rolling member group including three or more rolling members arranged to surround the motor axis. The motor shaft is a hollow shaft. At least a part of the output shaft is located inside the motor shaft. The motor shaft and the output shaft are supported with each other in the axial direction and the radial direction via the rolling member group.

One aspect of an electric actuator of the present invention includes: a motor having a motor shaft rotatable about a motor axis; a transmission mechanism coupled to one side in the axial direction of the motor shaft; an output shaft extending in the axial direction of the motor shaft and to which rotation of the motor shaft is transmitted via the transmission mechanism; and a rolling member group including three or more rolling members arranged to surround the motor axis. The motor shaft is a hollow shaft. At least a part of the output shaft is located inside the motor shaft. The motor shaft and the output shaft are supported with each other in the axial direction and the radial direction via the rolling member group.

A method is disclosed for controlling a drill-free curve-CVT including a ring wheel, a set of planet wheels, and a sun wheel, wherein the ring and sun wheel are clamped together. The normal forces between the ring and sun wheel on the one hand and the planet wheels on the other hand are well defined when the transmission ratio is constant. The normal forces for constant ratio are called the static values. The method is configured so that during a continuous increase or decrease of the transmission ratio, any force component added to the static values of the first and/or the second normal force is either zero or smaller than a predefined force component to maintain a microslip condition of the rolling contacts between the planet wheels and the ring and sun wheels. This control of the forces is applied regardless of the speed of the ratio change.

A method is disclosed for controlling a drill-free curve-CVT including a ring wheel, a set of planet wheels, and a sun wheel, wherein the ring and sun wheel are clamped together. The normal forces between the ring and sun wheel on the one hand and the planet wheels on the other hand are well defined when the transmission ratio is constant. The normal forces for constant ratio are called the static values. The method is configured so that during a continuous increase or decrease of the transmission ratio, any force component added to the static values of the first and/or the second normal force is either zero or smaller than a predefined force component to maintain a microslip condition of the rolling contacts between the planet wheels and the ring and sun wheels. This control of the forces is applied regardless of the speed of the ratio change.

A nonlinear closed-loop control combined with an integral time-delay feedback control is disclosed to adjust a speed ratio of an infinitely variable transmission (IVT) system. A speed ratio control for an IVT system involves a forward speed controller and a crank length controller for different speed ranges. The time-delay control is designed to reduce speed fluctuations of the output speed of an IVT with an accurate speed ratio. The speed ratio of an IVT with the disclosed control strategy can achieve an excellent tracking response for the desired constant output speed and reduce speed fluctuations of the output speed of an IVT by the time-delay feedback control.

A nonlinear closed-loop control combined with an integral time-delay feedback control is disclosed to adjust a speed ratio of an infinitely variable transmission (IVT) system. A speed ratio control for an IVT system involves a forward speed controller and a crank length controller for different speed ranges. The time-delay control is designed to reduce speed fluctuations of the output speed of an IVT with an accurate speed ratio. The speed ratio of an IVT with the disclosed control strategy can achieve an excellent tracking response for the desired constant output speed and reduce speed fluctuations of the output speed of an IVT by the time-delay feedback control.

A transmission assembly includes a ring gear configured to receive an input torque from a power source, a carrier assembly coupled to the ring gear, the carrier assembly configured to rotate about a first axis and including a housing, and a spider gear rotatably coupled to the housing, a carrier outlet shaft including a carrier outlet gear in meshed engagement with the spider gear, wherein the carrier outlet shaft is configured to transmit an output torque to a driveshaft, a control shaft including a control gear in meshed engagement with the spider gear, and a load applicator coupled to the control shaft, wherein the load applicator is configured to provide a resistive torque to the control shaft to resist rotation of the control shaft and vary a gear ratio between the driveshaft and the input shaft.