Abstract: An agricultural row unit for use with a towing frame hitched to a tractor includes an attachment frame adapted to be rigidly connected to the towing frame, a linkage pivotably coupled to the attachment frame, and a row unit frame having a leading end pivotably coupled to the linkage to permit vertical pivoting movement of the row unit frame relative to the attachment frame. A hydraulic cylinder coupled to the attachment frame and the linkage, for urging the row unit frame downwardly toward the soil, includes a movable ram extending into the cylinder, and a hydraulic-fluid cavity within the cylinder for receiving pressurized hydraulic fluid for advancing the ram in a direction that pivots the linkage and the row unit frame downwardly toward the soil.

Abstract: An agricultural row unit for use with a towing frame hitched to a tractor includes an attachment frame adapted to be rigidly connected to the towing frame, a linkage pivotably coupled to the attachment frame, and a row unit frame having a leading end pivotably coupled to the linkage to permit vertical pivoting movement of the row unit frame relative to the attachment frame. A hydraulic cylinder coupled to the attachment frame and the linkage, for urging the row unit frame downwardly toward the soil, includes a movable ram extending into the cylinder, and a hydraulic-fluid cavity within the cylinder for receiving pressurized hydraulic fluid for advancing the ram in a direction that pivots the linkage and the row unit frame downwardly toward the soil.

Abstract: An agricultural row unit includes a linkage assembly that is pivotably coupled to an attachment frame. A hydraulic cylinder is coupled to the linkage assembly and applies pressure to the linkage assembly. A controller is mounted in the row unit such that is coupled to the hydraulic cylinder for controlling the pressure applied by the hydraulic cylinder.

Abstract: An agricultural row unit includes a linkage pivotably coupled to an attachment frame, and a row unit frame with a leading end pivotably coupled to the linkage. A hydraulic cylinder is coupled to the attachment frame and the linkage, for urging the row unit frame downwardly toward the soil, and includes a movable ram extending into the cylinder. A hydraulic-fluid cavity is located within the cylinder for receiving pressurized hydraulic fluid for advancing the ram in a direction that pivots the linkage and the row unit frame downwardly toward the soil. An accumulator is positioned adjacent to the hydraulic cylinder and has a fluid chamber containing a diaphragm, with the portion of the chamber on one side of the diaphragm being connected to the hydraulic-fluid cavity in the hydraulic cylinder, and the portion of the chamber on the other side of the diaphragm containing a pressurized gas.