Patent · US Expired

Line pressure control arrangement for automatic automotive transmission

US4972738A · kind A · utility

4Cited by
11References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 11, 1989
Grant dateNov 27, 1990
Priority date
Expiry dateApr 11, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/0255
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

During non-shift modes of transmission operation, the line pressure is controlled according to a first control schedule. Upon a shift being initiated a second control schedule is used. The use of this schedule is maintained until such time as the ratio of the transmission input shaft rotational speed to the transmission output shaft rotational speed reaches a predetermined limit whereafter a third control schedule is utilized. Control is switched from the third control schedule to the first one upon the expiration of a predetermined period which is timed from the point in time a decision that a shaft between gears of the transmission should be implemented.

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