Patent · US Expired

Method of controlling a CVT speed ratio

US6721643B1 · kind B1 · utility

9Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 2002
Grant dateApr 13, 2004
Priority date
Expiry dateOct 12, 2022

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/66254
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A method is provided for controlling an output/input speed ratio of a continuously variable transmission (CVT) plant including primary and secondary pulleys actuated by primary and secondary pressures (Pp,Ps,), respectively, which generate forces to move the pulleys and adjust a corresponding belt, thereby adjusting the output/input ratio. The method includes calculating a desired force ratio for the CVT plant. Desired primary and secondary pressures (PP,PS) are then determined based, in part, upon the calculated desired force ratio, and the desired PS and PP signals are sent to the CVT plant to control operation of the CVT plant. An actual speed ratio is calculated based on measurements of input and output speed from the CVT plant. An error signal is generated based upon the measured actual speed ratio for use in calculating a next sample time desired force ratio which is then used to calculate desired PS and PP signals to be sent as inputs to the CVT plant, thereby using the desired force ratio as the controlled variable in controlling the output/input speed ratio of the CVT plant.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.