Patent · US Expired

Transmission control with a clutch priority valve

US4756213A · kind A · utility

14Cited by
13References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 1, 1987
Grant dateJul 12, 1988
Priority date
Expiry dateJun 1, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19251
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic transmission control uses a plurality of solenoid valves to control the engagement of friction devices during the shifting of a transmission between gear ratios. A clutch priority valve is provided to prevent the continuous simultaneous engagement of friction devices which will establish more than one ratio. Also provided is a manually controlled valve which permits the operator to determine the range in which the transmission will operate. If the clutch priority valve has been actuated, the transmission ratio can be controlled between a low ratio, for example, second gear, and a high ratio, for example, third or fourth gear, by use of the manual valve in combination with an actuator mode valve. The clutch priority valve, when actuated, is also operable to disengage a torque converter clutch.

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