Abstract: An agricultural harvesting combine is provided with a hydraulically positioned reel at the forward end of the combine. One single acting hydraulic cylinder is carried at each end of the reel. Hydraulic fluid is supplied to the cylinders through a rotary flow divider to cause each cylinder to synchronously be displaced to raise both ends of the reel in unison.

Abstract: A self propelled combine having forward main drive wheels and rear steerable wheels. A hydrostatic drive including a variable displacement motor is arranged to drive the main drive wheels. An electronic-hydraulic control system is automatically operable to drive the rear steerable wheels in response to sensing preselected pressure and combine attitude values while automatically varying the displacement of the hydrostatic drive motor to minimize combine speed changes and to provide torque as required under varying loads imposed by hilly terrain or increasing amounts of grain collected in the grain tank of the combine.

Abstract: A self-propelled combine for harvesting a crop and including a crop threshing and separating mechanism and a feeder for feeding crop material into the threshing and separating mechanism. The feeder has an electro-hydraulic control system for engaging and disengaging drive to the feeder. An electronic control system monitors the speed of the feeder drive and actuates the electro-hydraulic control system to disengage the feeder drive in response to sensing feeder drive speed below a predetermined minimum.

Abstract: an open center hydraulic system in which a pair of flow divider valves is connected in series with the system's hydraulic pump to create a parasitic pressure upstream of these flow valves and the feeder and separator clutches are controlled remotely by simple solenoid actuated two-position valves. The cylinders actuating the clutches are of sufficient size upon application of the minimum parasitic pressure to hold the clutches in a given position so that no center neutral position is necessary on the two-position valves.