04295532 is referenced by 65 patents and cites 12 patents.

A double disc attachment for planters, operating to present a debris-cleared area ahead of the furrow opener of the planter, has one of the discs peripherally fluted so that the discs cooperate in their debris-clearing function rather than work in opposition to one another. The fluting permits lateral displacement by the other disc of debris which might otherwise be contacted simultaneously by the soil-penetrating cutter disc and left lying across the path of the oncoming furrow opener. The discs are properly oriented insofar as tilt, spacing, convergence, relative overlapping and lead are concerned, with at least certain of such relative positioning and depth being adjustable to accommodate for various conditions.

Title
Planter with cooperating trash clearing discs
Application Number
6/90790
Publication Number
4295532
Application Date
November 2, 1979
Publication Date
October 20, 1981
Inventor
Terry K Gigot
Garden City
KS, US
C Dean Gigot
Garden City
KS, US
Forrest E Robertson
Garden City
KS, US
Donald E Williams
Garden City
KS, US
Agent
Schmidt Johnson Hovey & Williams
Assignee
Acra Plant
KS, US
IPC
A01C 5/06
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