#$%^&*AU2017203627B220191003.pdf#####APPARATUS, SYSTEMS AND METHODS FOR ROW UNIT DOWNFORCE CONTROL ABSTRACT A system for applying downforce to an agricultural implement having multiple row units, the system comprising a first actuator (500), said first actuator (500) disposed to apply force to a first row unit (10), said first actuator (500) including a first down chamber (515) and a first lift chamber (535), pressure in said first down chamber (515) tending to oppose pressure in said first lift chamber (535)； a second actuator, said second actuator disposed to apply force to a second row unit, said second actuator including a second down chamber (525) and a second lift chamber, pressure in said second down chamber (525) tending to oppose pressure in said second lift chamber； a first downpressure control device (317) in fluid communication with said first down chamber (515) for controlling pressure in said first down chamber (515), said first downpressure control device (317) configured to maintain as a selected first downpressure any one of a continuous range of pressures in said first downpressure chamber (317)； a second downpressure control device (315) in fluid communication with said second down chamber (525) for controlling pressure in said second down chamber (525), said second downpressure control device (315) configured to maintain as a selected second downpressure any one of a continuous range of pressures in said second downpressure chamber, wherein said selected second downpressure is different from said selected first downpressure； and a lift pressure control device (310) in fluid communication with both said first lift chamber (535) and said second lift chamber for controlling pressure in said first lift chamber (535) and said second lift chamber, said lift pressure control device (310) configured to maintain as a selected lift pressure any one of a continuous range of pressures in both said first lift cham
