Patent · US Expired

Control apparatus for hydraulically operated vehicular transmission

US5887483A · kind A · utility

5Cited by
4References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 1997
Grant dateMar 30, 1999
Priority date
Expiry dateSep 23, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/1926
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

When switching to a forward running is made while a vehicle is running in a reverse direction, a switching to the forward running condition is made at an early time to thereby prevent the deterioration of the durability of the hydraulic engaging element due to slipping. For that purpose, when a vehicle speed (V) has exceeded a predetermined value (YVa) in a reverse range (R) and also when the vehicle speed (V) has never fallen below the predetermined value (YVa) in a neutral range (N), a reverse signal (FREV=1) is outputted. If FREV=1 at the time of switching to the forward range, the relationship between the vehicle speed and the speed stage (speed change map) is set to one (a reverse-running-measure speed change map) which is different from that at an ordinary time, to thereby determine the speed stage to be established. Then, a low speed stage is established even at a relatively high vehicle speed. Switching is thus made at an early time to the forward running condition with a large torque to be transmitted via the low speed stage.

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