Patent · US Expired

Control method and control system for automatic transmission

US5630772A · kind A · utility

15Cited by
10References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1995
Grant dateMay 20, 1997
Priority date
Expiry dateApr 25, 2015

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2312/02
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A system and method for controlling an automatic transmission in a vehicle drive train including an engine, the automatic transmission and a fluid coupling for transmitting the rotation of the engine to the transmission. The transmission includes a clutch applied when a forward running range is selected; a second one-way clutch which is applied, when the first clutch is applied, to establish a forward 1st speed; and a brake for locking the one-way clutch, when applied, to block the reverse rotation of the output shaft of the transmission. A first hydraulic servo receives a first oil pressure for applying the first clutch and a second hydraulic servo receives a second oil pressure for applying the brake. When a forward running range is selected, with the vehicle stopped, the engine idling and a foot brake engaged, the oil pressure of the first hydraulic servo is lowered from the oil pressure at the 1st speed whereas the oil pressure of the second hydraulic servo is raised to a modulated pressure. The modulated pressure is set to generate, against the reverse force on the vehicle facing up an incline, a resistance corresponding to the forward driving force generated when the engine i…

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