Patent · US Expired

Hydraulic control system for automatic transmission

US4395926A · kind A · utility

10Cited by
2References
2Claims
0Family size

Assignees

Inventors

Key dates

Filing dateAug 15, 1980
Grant dateAug 2, 1983
Priority date
Expiry dateAug 15, 2000

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/026
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic control system for an automatic transmission including a fluid coupling type torque converter, and a gear system provided with two or more frictional devices adapted to establish two or more speed conditions. The hydraulic control system includes a hydraulic pressure source, a line pressure control valve receiving pressure from the hydraulic pressure source to generate a regulated line pressure, a throttle pressure control valve for generating a throttle pressure commensurate with the intake throttle opening, a governor pressure control valve for generating a governor pressure commensurate with the vehicle speed, a detent regulator valve receiving the line pressure to generate a regulated detent pressure, a manual valve for enabling manual shifts of the transmission, two or more shift valves for shifting the paths of the line pressure to the frictional engaging devices in response to the opposingly acting forces of the throttle pressure and governor pressure, the shift valves including one shift valve operative to establish the highest speed ratio for the transmission, and a control valve provided in the shift valve for the highest speed ratio and adapted to draw in the…

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