Patent ID: 7311466

Claim:
A subgrade preparation apparatus for leveling, grading and compacting a subgrade surface for receiving concrete thereon, said subgrade preparation apparatus comprising: a base unit positionable on a support surface adjacent to a targeted subgrade area; a support boom extending from said base unit; and a subgrade head assembly adjustably mounted on said support boom, said subgrade head assembly being vertically adjustable relative to said support boom to be lowered onto a subgrade surface at the targeted subgrade area, said subgrade head assembly including a framework, a plow and a material moving device for moving material toward at least one side of said subgrade head assembly for establishing the subgrade surface, said plow having a longitudinal axis and an outer end, said subgrade head assembly including a plow end plate pivotally attached at said outer end and pivotable about a generally horizontal pivot axis that is generally transverse to a longitudinal axis of said plow, said plow end plate being pivotable between a raised postion, where said plow end plate is generally horizontally oriented and generally transverse to said longitudinal axis of said plow, and a lowered position, where said plow end plate is generally vertical and is positioned at said outer end of said plow and generally transverse to said longitudinal axis of said plow to form an end portion of said plow to limit plowed material from flowing around said outer end of said plow as said subgrade head assembly is moved over and along the subgrade surface at the targeted subgrade area.