Patents Represented by Attorney C. H. Graze
  • Patent number: 4495838
    Abstract: Disclosed is an automatic control system for a powershift, preselect transmission (10) including a plurality of power paths (36, 38) alternately connectable between input (12) and output (20) shafts by first engaging selected ones of synchronizer clutches (42, 74, 84) associated with each of a plurality speed ratio gears (44, 46, 76, 78, 80) in each path and then alternately engaging a powershift clutch (48, 82) associated with each path. The control system includes a hydraulic logic system (118) which may be electronic and a hydraulic and shift valve system which may be electrically controlled should the logic be electronic. The control system preselects ratio gears in a nondriving path and then alternately engages the powershift clutches to switch driving connections from one path to the other. The logic system includes an improved reverse sequence valve (132) and improved shift valves (124, 126, 128).
    Type: Grant
    Filed: December 16, 1981
    Date of Patent: January 29, 1985
    Assignee: Eaton Corporation
    Inventor: Douglas C. Gooch