Patent · US Expired

Control system for belt-type continuously variable transmission

US5427579A · kind A · utility

36Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1993
Grant dateJun 27, 1995
Priority date
Expiry dateSep 30, 2013

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/66259
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A belt-type continuously variable transmission has a drive pulley coupled to an input shaft, a driven pulley coupled to an output shaft, a V-belt trained around the drive and driven pulleys, a drive-pulley cylinder for varying the pulley width of the drive pulley, and a driven-pulley cylinder for varying the pulley width of the driven pulley. The belt-type continuously variable transmission is controlled by a control system including a high-pressure regulator valve for producing high-pressure control oil under a high control pressure, a low-pressure regulator valve for producing low-pressure control oil under a low control pressure which is lower than the high control pressure, a shift valve for selectively supplying the high-pressure control oil and the low-pressure control oil to the drive-pulley cylinder and the driven-pulley cylinder, and a shift controller for controlling the shift valve to move in a direction to eliminate an difference between a target speed ratio control value and a present speed ratio control value from a reference position in which an axial thrust force ratio between an axial thrust force required to be applied by the drive-pulley cylinder and an axial thr…

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