Patent · US Expired

Transmission speed matching control

US5265018A · kind A · utility

14Cited by
17References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 3, 1991
Grant dateNov 23, 1993
Priority date
Expiry dateJun 3, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2312/06
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A vehicle transmission system having shift levers mechanically linked to couplers for selection of ranges of gear speed ratios and electro-hydraulic powershift clutches for selection of a gear speed ratio within the selected range is provided with controls for avoiding unexpected speeds or speed changes under certain conditions. If the vehicle is moving at start-up as a result of a stall or accidental reset of the microprocessor, and the shift levers have not been moved since the stall or reset, the microprocessor retrieves from a nonvolatile memory an indication of the last selected powershift gear prior to the reset and uses it for the initial powershift gear selection. When an operator depresses a clutch, shifts a shift lever and then changes his mind and shifts the shift lever back to its original position before releasing the clutch above a threshold point, the microprocessor selects the powershift gear in effect at the time the clutch pedal was depressed.

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