Patent · US Expired

Automatic transmission control system having two accumulators for four clutches controlled by a single accumulator back pressure valve

US5399131A · kind A · utility

10Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1993
Grant dateMar 21, 1995
Priority date
Expiry dateJan 28, 2013

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/0258
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

An automatic transmission control system includes a hydraulic circuit for controlling coupling pressure supplied to frictional coupling elements of the automatic transmission, which are selectively coupled and uncoupled so as to shift the automatic transmission into desired gears. The hydraulic circuit has a solenoid valve, for regulating a principal hydraulic pressure to provide a control pressure in accordance with vehicle driving conditions. The coupling pressure, supplied to a frictional coupling element, is regulated by a regulating valve in accordance with a control pressure level, and during shifting of the automatic transmission, is supplied through an accumulator whose back pressure is controlled in accordance with the control pressure by a control valve.

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