Patent · US Expired

Double-downshift gear strategy for a dual clutch automatic transmission

US6869382B2 · kind B2 · utility

27Cited by
41References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 7, 2003
Grant dateMar 22, 2005
Priority date
Expiry dateMay 7, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19228
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A method of double-downshifting from a first gear ratio to a second gear ratio includes the steps of first reducing torque transfer from a first clutch to a first driven gear. Engine speed then increases. Next, torque transfer from a second clutch to a third driven gear is increased while simultaneously the first clutch is disengaged from the first driven gear. Torque transfer from the second clutch to the third driven gear is then reduced. Torque transfer from the second clutch to the third driven gear is next increased. The first clutch is engaged to the second driven gear. Then, torque transfer from the first clutch to the second driven gear is increased while simultaneously the torque transfer from the second clutch to the third driven gear is reduced. Finally, the second clutch is disengaged from the third driven gear.

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