Patent · US Expired

Hydraulic control system for controlling line pressure based on backtorque and throttle rate in an automatic transmission

US5349885A · kind A · utility

8Cited by
8References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 27, 1992
Grant dateSep 27, 1994
Priority date
Expiry dateAug 27, 2012

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/0096
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

An automatic transmission includes a multi-speed transmission gear mechanism having an input shaft, an output shaft and a plurality of friction coupling elements. A hydraulic control system selectively supplies a hydraulic pressure to the friction coupling elements, thereby selectively applying the friction coupling elements to cause the transmission gear mechanism to shift to a speed which is determined according to a predetermined shift pattern. The control system sets a target hydraulic pressure to be applied to the friction coupling elements according to the kind of the shift to be effected and the engine load, and, when it is detected that the transmission gear mechanism is to make a backout upshift due to reduction in the engine load, increases the target hydraulic pressure by an amount which is determined according to the throttle opening and the turbine speed.

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