08544398 is referenced by 25 patents and cites 305 patents.

In one embodiment, 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 support member is pivotably coupled to the attachment frame to permit vertical pivoting movement of the support member relative to the attachment frame, and at least one furrow-closing device is mounted on the support member. A hydraulic cylinder is coupled to the support member for urging the row unit frame downwardly toward the soil. The hydraulic cylinder includes a movable ram extending into the cylinder, and a hydraulic-fluid cavity within the cylinder for receiving pressurized hydraulic fluid for urging the ram in a first direction that pivots the support member in a first vertical direction. An accumulator has a fluid chamber containing a pressurized gas for urging the ram in a second direction that pivots the support member in a second vertical direction.

Title
Hydraulic down pressure control system for closing wheels of an agricultural implement
Application Number
13/75574
Publication Number
8544398 (B2)
Application Date
March 30, 2011
Publication Date
October 1, 2013
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 63/32
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