Patent · US Expired

Shift hunting prevention for an automatic transmission

US5669850A · kind A · utility

19Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 13, 1996
Grant dateSep 23, 1997
Priority date
Expiry dateJun 13, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/1926
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear of a four speed automatic transmission.

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