Patent · US Expired

Method of controlling hydraulic pressure for an automatic transmission gear system

US4813307A · kind A · utility

11Cited by
11References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 26, 1987
Grant dateMar 21, 1989
Priority date
Expiry dateJun 26, 2007

Classification

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

Abstract

A method of controlling the hydraulic pressure for an automatic transmission gear system, in which the actual rotation speed of a rotatable element during a speed shift from, for example, the 1st speed ratio to the 2nd speed ratio is detected, and the hydraulic pressure supplied to a frictional engaging element acting to change the rotation speed of the rotatable element is controlled so that the rate of change of the rotation speed of the rotatable element can converge to a predetermined change rate when the speed change rate due to the speed shift is ideal. On the other basis of the hydraulic pressure supplied to the frictional engaging element in the final state of the speed shift, the initial hydraulic pressure to be supplied to the frictional engaging element immediately after starting of the next speed shift is computed. Such a trial is repeated a plurality of times so that an automatic transmission whose operating hydraulic pressure is not primarily designed to meet the operation of an engine from the aspect of the capacity can be adapted to operate with the engine.

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