04766962 is referenced by 28 patents and cites 13 patents.

A furrow forming apparatus for a seed planter is disclosed wherein the construction facilitates convenient adjustment of spring-biasing exerted on furrow forming disks of the assembly. The apparatus includes a parallel linkage which permits relative vertical movement of the disks. Springs operatively associated with the linkage are positionable for creating either downward or upward pressure on the disks. Adjustment of the springs is accommodated by the provision of an upper support rod which receives upper ends of the springs, with the support rod selectively positionable along upper links of the parallel linkage by the provision of an adjustable rack and pinion mounting arrangement.

Title
Furrow forming apparatus for attachment to a tool bar
Application Number
6/923280
Publication Number
4766962
Application Date
October 27, 1986
Publication Date
August 30, 1988
Inventor
Roland J Frase
Roselle
IL, US
Agent
Dressler Goldsmith Shore Sutker & Milnamow
Assignee
J I Case Company
WI, US
IPC
A01B 39/22
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