Patent · US Expired

Lock up control of a hydraulic torque converter type automatic transmission

US4687083A · kind A · utility

14Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 22, 1984
Grant dateAug 18, 1987
Priority date
Expiry dateMar 22, 2004

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/143
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A vehicle automatic transmission including a torque converter having a lock up clutch. A lock up control circuit is provided and has a memory including a first lock up control line for controlling the engagement and release of the lock up clutch when the torque converter turbine speed is close to the pump impeller speed, and a second lock up control line which is drawn along a line wherein the engine output torque is substantially zero so that the lock up clutch is released at a given engine load when the turbine speed is decreased beyond the first lock up control line, or when the turbine speed is increased beyond the second lock up control line.

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