Grading machine having rotary cutting drums

Claim 1

A GRADING MACHINE COMPRISING: A VEHICLE, A NORMALLY HORIZONTAL, ROTARY, CYLINDRICAL CUTTING DRUM AT THE FRONT END OF SAID VEHICLE HAVING ITS CENTRAL AXIS IN A PLANE APPROXIMATELY NORMAL TO A LONGITUDINAL AXIS OF THE VEHICLE, A SUPPORTING FRAME ON SAID VEHICLE INCLUDING A PAIR OF SUPPORTING MEMBERS STRADDLING THE ENDS OF SAID DRUM AND MEANS SUPPORTING THE ENDS OF SAID DRUM ON SAID SUPPORTING MEMBERS FOR ROTATION OF THE DRUM ON ITS CENTRAL AXIS, A PAIR OF ROTARY, CONICAL CUTTING DRUMS AT THE ENDS OF SAID CYLINDRICAL DRUM, RESPECTIVELY, OUTBOARD OF SAID SUPPORTING MEMBERS, THE LARGE ENDS OF SAID CONICAL DRUMS BEING LOCATED PROXIMATE TO SAID SUPPORTING MEMBERS AND THE CENTRAL AXES OF SAID CONICAL DRUMS SLOPING DOWNWARDLY AS THE AXES APPROACH THE SMALL, OUTER ENDS OF SAID CONICAL DRUMS, MEANS ROTATABLY SUPPORTING SAID CONICAL DRUMS ON SAID SUPPORTING MEMBERS FOR ROTATION OF SAID CONICAL DRUMS ON THEIR CENTRAL AXES, THE CUTTING RADII OF SAID DRUMS BEING APPROXIMATELY TANGENT ALONG SUBSTANTIALLY THE ENTIRE LENGTH OF EACH DRUM TO A PLANE PASSING BELOW THE DRUMS NORMAL TO SAID FIRST PLANE AND THE POINT OF TANGENCY OF THE CUTTING RADIUS OF THE LARGE END OF EACH CONICAL DRUM WITH SAID LATTER PLANE BEING PROXIMATE TO THE POINT OF TANGENCY OF THE CUTTING RADIUS OF THE ADJACENT END OF SAID CYLINDRICAL DRUM WITH SAID LATTER PLANE, AND MEANS INCLUDING A ROTARY POWER TRANSMISSION MECHA NISM EXTENDING BETWEEN THE LARGE END OF EACH CONICAL DRUM AND THE ADJACENT END OF THE CYLINDRICAL DRUM FOR DRIVING SAID DRUMS IN ROTATION.