3749035 is referenced by 82 patents and cites 7 patents.

A precision depth planter including a plurality of furrow-forming units mounted on a main frame for relative vertical movement, each unit including a pair of depth gauge wheels for carrying the unit and for regulating the depth of the furrow formed thereby. A seed dispensing unit is mounted on the frame directly above each furrow-forming unit and includes a seed container and selecting mechanism for delivering seeds to the furrow, the several selecting mechanisms being commonly driven from a drive shaft extending transversely between the dispensing units. A separate hydraulic cylinder acts on each furrow-forming unit to maintain a constant force on said unit regardless of the position thereof relative to the main frame. A ground-engaging sensing unit mounted on the planter frame measures soil hardness and in conjunction with a hydraulic control valve acts to vary the force exerted by the hydraulic cylinders to maintain a uniform planting depth irrespective of variations in soil hardness.

Precision depth seed planter
Application Number
Publication Number
Application Date
December 28, 1970
Publication Date
July 31, 1973
Johnson Leslie William
Cayton David Walter
Deere & Company
A01c 05/00
A01C 07/00
A01C 07/20
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