| 主权项 |
1. An agricultural implement for use with a towing frame hitched to a tractor having a hydraulic system for supplying pressurized hydraulic fluid to said implement, said implement comprising at least one row unit comprising:
an attachment frame adapted to be rigidly connected to said towing frame, a plurality of support members, each of which is pivotably coupled to said attachment frame or another of said support members to permit vertical pivoting vertical movement of said support members, a plurality of soil-engaging tools, each of which is coupled to at least one of said support members, a plurality of hydraulic cylinders, each of which is coupled to one of said support members for urging the respective support member downwardly toward the soil, each of said hydraulic cylinders including a movable ram extending into said cylinder, a plurality of hydraulic lines, each of which is coupled to at least one of said hydraulic cylinders for supplying pressurized hydraulic fluid to the respective cylinders, a plurality of controllable pressure control valves, each of which is coupled to one of said hydraulic lines for controlling the pressure of hydraulic fluid supplied by the respective hydraulic lines to the respective cylinders, a plurality of sensors, each of which produces an electrical signal corresponding to a predetermined condition, and at least one controller coupled to said sensors and said controllable pressure control valves, said controller being adapted to receive said electrical signal from said sensors and produce control signals for controlling said pressure control valves. |
