Patent ID: 8186450

Claim:
A zone tillage tool for tilling soil in a plurality of parallel elongated zones in a farm field with the zones being laterally spaced apart or separated from one another by untilled portions of the farm field, which comprises: (a) a laterally extending tool bar overlying the farm field and movable across the farm field in a forward direction of motion; (b) a plurality of rotary tillage coulters operatively carried on the tool bar with each tillage coulter rotating about a substantially horizontal axis for rolling over the farm field in engagement with the soil, wherein the tillage coulters are parallel to one another, rotate in planes that are parallel to the forward direction of motion of the tool bar, and are laterally spaced apart from one another along the tool bar by a lateral spacing equal to the lateral spacing of the zones such that a single rotary tillage coulter tills the soil to form a single zone, each tillage coulter having a circumference that is notched to provide a plurality of teeth having leading edges taken with reference to a direction of rotation of the coulter as the tool frame is moved forwardly over the zone; and (c) a plurality of substantially radially extending shovel bits carried around the circumference of each tillage coulter, wherein each shovel bit has at least a portion which forms a substantially radially extending and laterally projecting wing on at least one face of the tillage coulter which wing lifts and loosens the soil in the zone as the tillage coulter rolls along the zone and the shovel bit is inserted into and rotated through the soil in the zone by rotation of the tillage coulter, wherein the laterally projecting wings of the shovel bits are the only laterally projecting members carried on the tillage coulter that act on or till the soil in the zone along which the tillage coulter rolls, and wherein the shovel bits are carried by the teeth of the tillage coulters with the shovel bits being located in a trailing position behind the leading edges of the teeth that carry the shovel bits to expose the leading edge of each tooth to the soil to permit the leading edge of each tooth to enter the soil before the shovel bit carried by said tooth enters the soil.