08776702 is referenced by 14 patents and cites 336 patents.

An agricultural row unit includes an attachment frame adapted to be rigidly connected to a towing frame, and a linkage assembly pivotably coupled to the attachment frame to permit vertical pivoting movement of the linkage assembly relative to the attachment frame. A hydraulic cylinder is coupled to the linkage assembly for urging the linkage assembly downwardly toward the soil, and an accumulator is mounted to the hydraulic cylinder for supplying pressurized gas to the hydraulic cylinder urging the linkage assembly upwardly away from the soil. A manifold is removably mounted to the hydraulic cylinder via a mounting interface, the manifold being selected from a group of different types of modular manifolds in which each manifold is removably mountable to the hydraulic cylinder, one at a time, via the same mounting interface, the manifold having two hydraulic-fluid ports including an inlet port and an outlet port.

Title
Hydraulic down pressure control system for an agricultural implement
Application Number
13/561934
Publication Number
8776702 (B2)
Application Date
July 30, 2012
Publication Date
July 15, 2014
Inventor
Joseph D Bassett
Sycamore
IL, US
Agent
Nixon Peabody
Assignee
Dawn Equipment Company
IL, US
IPC
A01B 23/06
A01B 15/18
A01B 15/16
A01B 15/14
A01B 7/00
A01B 5/10
A01B 23/04
A01B 21/08
A01B 63/32
A01B 61/04
A01C 5/00
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