Patent ID: 7096971

Claim:
A grader designed to be transported by a self propelled machine; the grader comprising: a rigid overhead support attachable to the self-propelled machine so as to extend therefrom substantially horizontal to the earth surface to be graded and to extend substantially parallel to the direction of travel; a substantially rectangular rigid frame having a leading edge and a trailing edge and end stringers attaching between said leading edge and said trailing edge; a pair of blades, one fastening to each of said leading edge and said trailing edge of said substantially rectangular rigid frame; a rearward pair of chain lengths, each attached to said substantially rectangular rigid frame and adjacent to said trailing edge and one of said end stringers and attached to said rigid overhead support; a forward pair of chain lengths, each attached to said substantially rectangular rigid frame and adjacent to said leading edge and one of said end stringers and attached to said rigid overhead support; said forward pair of chain lengths and said rearward pair of chain lengths attaching to said substantially rectangular rigid frame at a separation distance s, said forward pair of chain lengths and said rearward pair of chain lengths attaching to said rigid overhead support at a support member separation S, wherein S>s.