Patent · US Expired

Control of toroidal continuously variable transmission

US6604039B2 · kind B2 · utility

3Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 18, 2002
Grant dateAug 5, 2003
Priority date
Expiry dateJul 18, 2022

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H37/022
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

The trunnion (23) of a vehicle toroidal continuously variable transmission is displaced by a step motor (52) via a control valve (56) and oil pressure servo cylinder (50) in order to vary a speed ratio of the transmission. A controller (80) calculates a target value (z*) of a control variable (z) based on an accelerator pedal depression amount (APS) and output disk rotation speed (&ohgr;co) (S5). Further, a time-variant coefficient (f) showing the relation between the trunnion displacement (y) and variation rate ({dot over (&phgr;)}) of the gyration angle (&phgr;) of the power roller, is calculated (S10). The error between the speed change response of the transmission and a target linear characteristic can be decreased by determining a command value (u) to the step motor (52) under a control gain determined based on a time differential ({dot over (f)}) of the coefficient (f) (S20).

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