Patent · US Expired

Hydraulic transmission controller with coupling pressure compensation

US4928557A · kind A · utility

20Cited by
16References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 23, 1988
Grant dateMay 29, 1990
Priority date
Expiry dateNov 23, 2008

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/0087
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic control apparatus for controlling a frictional coupling device of an automatic transmission for a motor vehicle includes a shift valve for effecting an engaging action of the coupling device from a first position to a second position, and an accumulator for reducing a change in a hydraulic pressure applied to the coupling device. The control apparatus is adapted to control a control value to regulate a back pressure of the accumulator, based on a parameter associated with an output of an engine, and according to a predetermined relationship between the control value and the parameter, so as to reduce a shifting shock of the transmission. The control apparatus includes a detector for detecting an engaging time of the engaging action of the coupling device. The control apparatus further includes a compensating device for updating the relationship between the control value and the parameter, depending upon the detected engaging time, with respect to a specific value of the parameter at which the engaging action takes place. The compensating device maintains the updated relationship for use for a subsequent engaging action of the coupling device from the first position to t…

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