05709271 is referenced by 66 patents and cites 59 patents.

An agricultural planter comprises a frame with a plurality of wheels and adapted to be towed by a tractor. The planter has a plurality of row planting units mounted on the frame and carrying planting implements, and the planting units are vertically movable relative to the frame. A soil-hardness sensing unit carried on the frame produces a signal representing the hardness of the soil. A controllable biasing device is connected to the planting units for adjusting the force applied to the soil by the planting units, in response to the signal representing the hardness of the soil.

Title
Agricultural planter
Application Number
189840
Publication Number
5709271
Application Date
September 22, 1995
Publication Date
January 20, 1998
Inventor
James H Bassett
Sycamore
IL, US
Agent
Arnold White & Durkee
Assignee
Dawn Equipment Company
IL, US
IPC
A01B 63/00
A01C 5/00
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