F16H61/664

Control device and control method for continuously variable transmission
11067172 · 2021-07-20 · ·

A control device for a continuously variable transmission performs transmission control so that an actual transmission control value becomes a target transmission control value. The control device includes a lead compensation unit, delay compensation unit, and a setting unit. The lead compensation unit performs lead compensation of the target transmission control value. The delay compensation unit performs delay compensation of the target transmission control value. The setting unit is configured to set as the target transmission control value a post-compensation target transmission control value for which compensation is performed by the lead compensation unit and the delay compensation unit according to at least one of an input side rotation speed of the continuously variable transmission, an input torque to a driven side rotation element of the continuously variable transmission, a transmission ratio of the continuously variable transmission, and a rate of change of the transmission ratio.

Control device and control method for continuously variable transmission
11067172 · 2021-07-20 · ·

A control device for a continuously variable transmission performs transmission control so that an actual transmission control value becomes a target transmission control value. The control device includes a lead compensation unit, delay compensation unit, and a setting unit. The lead compensation unit performs lead compensation of the target transmission control value. The delay compensation unit performs delay compensation of the target transmission control value. The setting unit is configured to set as the target transmission control value a post-compensation target transmission control value for which compensation is performed by the lead compensation unit and the delay compensation unit according to at least one of an input side rotation speed of the continuously variable transmission, an input torque to a driven side rotation element of the continuously variable transmission, a transmission ratio of the continuously variable transmission, and a rate of change of the transmission ratio.

Variators

A variator for a mechanical transmission system is disclosed. Transfer means are in rolling contact with input and output members of the variator to transfer rotary motion between them. The input member is coupled to the variator input through a first biasing device arranged to exert a first biasing force on the variator according to a first, input gain which relates input torque acting on the input member and the first biasing force. The output member is coupled to the variator output through a second biasing device arranged to exert a second biasing force on the variator according to a second, output gain which relates output torque acting on the output member and the second biasing force. The first and second biasing forces clamp the variator to provide traction. The first, input gain and second, output gain are different, which, at least in specific variator applications, optimises the traction coefficient.

CONTROL SYSTEM FOR POWER TRANSMISSION UNIT

A control system for a power transmission unit configured to shift an operating mode smoothly by manipulating engagement devices, and to simplify a structure of the power transmission unit. The control system is configured to reduce a speed difference between an axially stationary engagement element and a reciprocatable engagement element of a second engagement device when shifting from a first continuously variable mode to a second continuously variable mode by engaging the second engagement device. After the second engagement device has been engaged completely, a first engagement device is disengaged.

CONTROL SYSTEM FOR POWER TRANSMISSION UNIT

A control system for a power transmission unit configured to shift an operating mode smoothly by manipulating engagement devices, and to simplify a structure of the power transmission unit. The control system is configured to reduce a speed difference between an axially stationary engagement element and a reciprocatable engagement element of a second engagement device when shifting from a first continuously variable mode to a second continuously variable mode by engaging the second engagement device. After the second engagement device has been engaged completely, a first engagement device is disengaged.

SYSTEMS AND METHODS FOR CONTROLLING ROLLBACK IN CONTINUOUSLY VARIABLE TRANSMISSIONS

A continuously variable transmission capable of operating in a forward direction or reverse direction may be controlled in the reverse direction by providing an initial skew angle in a first skew direction, followed by a set or sequence of skew angle adjustments in an opposite direction to prevent runaway or other unintended consequences. A continuously variable transmission may include a timing plate to maintain all planets at an angle or within a range of an angle in forward and reverse operations.

SYSTEMS AND METHODS FOR CONTROLLING ROLLBACK IN CONTINUOUSLY VARIABLE TRANSMISSIONS

A continuously variable transmission capable of operating in a forward direction or reverse direction may be controlled in the reverse direction by providing an initial skew angle in a first skew direction, followed by a set or sequence of skew angle adjustments in an opposite direction to prevent runaway or other unintended consequences. A continuously variable transmission may include a timing plate to maintain all planets at an angle or within a range of an angle in forward and reverse operations.

Slip detection and mitigation for an electric drive powertrain having a high ratio traction drive transmission

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 a 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.

SKEW LIMITER FOR A TORIC-DRIVE CVT

A skew limiter for a toric-drive CVT is described herein. The skew limiter proposes a shaped piece that limits the skew angle to a known angle notwithstanding the tilt angle of the rollers.

Systems and methods for controlling rollback in continuously variable transmissions

A continuously variable transmission capable of operating in a forward direction or reverse direction may be controlled in the reverse direction by providing an initial skew angle in a first skew direction, followed by a set or sequence of skew angle adjustments in an opposite direction to prevent runaway or other unintended consequences. A continuously variable transmission may include a timing plate to maintain all planets at an angle or within a range of an angle in forward and reverse operations.