Patent ID: 8851203

Claim:
A vibratory drill head comprising: a housing; a spindle mounted to said housing for axial rotation, said spindle presenting a passage therethrough extending between upper and lower ends of said spindle to allow materials to move through said spindle; a sine generator in said housing coupled to said spindle between said upper end and said lower end of said spindle in a manner to apply a sinusoidal vibration to said spindle, wherein said sine generator comprises six eccentric rotors radially distributed about a center point, each said rotor having an eccentric weight, wherein all said eccentric weights reach top dead center and bottom dead center simultaneously, wherein each of said six eccentric rotors include an axis of rotation, wherein the six axes of rotation are spaced radially equidistant, and wherein each of said axes of rotation are tilted from horizontal; and an isolation mechanism in said housing acting between said sine generator and said housing to dampen the effect on said housing of the sinusoidal vibration applied to said spindle by said sine generator.