Patent · US Expired

Line pressure control apparatus of automatic transmission

US5906556A · kind A · utility

8Cited by
11References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1997
Grant dateMay 25, 1999
Priority date
Expiry dateOct 23, 2017

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H59/44
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A line pressure control apparatus of an automatic transmission controls the line pressure of the automatic transmission under a lockup condition to ensure an engagement capacity and an amount of lubrication oil for an engaged friction element under a high vehicle speed condition. The line pressure control apparatus comprises a line pressure lowering section, a vehicle speed deciding section and a pressure changing section. The pressure lowering section lowers a line pressure under a lockup condition of the automatic transmission. The vehicle speed deciding section decides whether a vehicle speed of the automotive vehicle is higher than a predetermined value. The pressure changing section changes the line pressure under the lockup condition from the lowered line pressure to a line pressure under a normal condition when the vehicle speed is higher than the predetermined value.

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