Sonic large bore earth auger

Claim 2

In an earth hole boring auger having cutter blade means and drive means for driving said cutter blade means rotatably around a centrally positioned axis, the improvement wherein means are provided to sonically drive said blade means unidirectionally with arcuate motion along the extended cutting edge of said blade means comprising: resonant bar means, means for supporting the resonant bar means on said drive means for rotation therewith, said resonant bar means being supported with a vibratory energy delivering portion thereof in proximity to a face portion of said cutter blade means located radially out from said centrally positioned axis and opposite to the cutting edge thereof, a mechanical oscillator having an orbiting rotor connected to said resonant bar means, and drive means for rotatably driving the rotor of said oscillator means so as to set up resonant standing wave vibrations of the resonant bar means, whereby resonant energy is transferred from said bar means to said cutter blade means in unidirectional torque pulses increasing in vibrational amplitude radially from said axis so as to vibrationally drive the cutting edge of said cutter means against the earthen material with arcuate vibration which provides a shearing type of vibratory turning action with resonant pulverizing force as the cutter blade drive means simultaneously drives the cutter blade means rotatably.

Claim 3

The device of claim 1 wherein said resonant bar means comprises a distributed longitudnal bar structure positioned around said axis, said cutter blade means comprising cutter blades also distributed around said axis.

Claim 4

An earth augering machine comprising: a central drive stem, a pair of cutter blades attached to said drive stem near one end thereof, said cutter blades extending laterally out from said drive stem in directions substantially normal to the longitudinal axis of said drive stem, a pair of resonant bar members, means for supporting said resonant bar members with their longitudinal axes substantially parallel to the longitudinal axis of said drive stem and with one end thereof proximate to the face of an associated one of said cutter blades opposite to the face of the cutting edge thereof, a mechanical oscillator having an orbiting rotor mounted on each of said resonant bars, drive means for rotatably driving the rotors of said oscillators at a speed such as to set up resonant elastic lateral mode vibration in each of said bars whereby said bars transfer unidirectional pulses of vibrational energy to the blades, and means for rotatably driving said stem and along with it the blades and resonant bars while the blades are being vibrationally driven by the bars.

Claim 5

An earth augering machine comprising: a central drive stem, a pair of cutter blades attached to said drive stem near one end thereof, said cutter blades extending laterally out from said drive stem in directions substantially normal to the longitudinal axis of said drive stem, a pair of resonant bar members, means for supporting said resonant bar members with their longitudinal axes substantially parallel to the longitudinal axis of said drive stem and with one end thereof proximate to the face of an associated one of said cutter blades opposite to the face of the cutting edge thereof, a mechanical oscillator having an orbiting rotor mounted on each of said resonant bars, drive means for rotatably driving the rotors of said oscillators at a speed such as to set up resonant elastic lateral mode vibration in each of said bars whereby said bars transfer unidirectional pulses of vibrational energy to the blades, and means for rotatably driving said stem and along with it the blades and resonant bars while the blades are being vibrationally driven by the bars.

Claim 6

The device of claim 3 wherein said means for supporting the bars and cutter blades on said central stem comprises a first and second set of trunnions separated from each other longitudinally and fixedly attached to said stem, bar means pivotally connected to said resonant bars and said cutter blades and means for attaching each of said bar means to its associated trunnion, said last mentioned attachment means comprising means for vibrationally isolating the bar means from the trunnions.

Claim 7

In an earth auger having cutter blade means and drive means for driving said cutter blade means around a centrally positioned axis, the improvement wherein means are provided to sonically drive said blade means unidirectionally with arcuate motion along the extended cutting edge of said blade means comprising: resonant bar means comprising at least a pair of longitudinal bars positioned opposite each other, means for supporting the longitudinal bars on said drive means for rotation therewith, said resonant bar means being supported with a vibratory energy delivering portion thereof in proximity to a face of said cutter blade means opposite to the cutting edge thereof, said cutter blade drive means comprising a central stem, said cutter blade means comprising a cutter blade associated with each of said bars, said cutter blades being attached at one end thereof to said stem and extending laterally away from said stem, said bars being positioned near the ends of the cutter blades opposite said one ends thereof, a mechanical oscillator having an orbiting rotor connected to said resonant bar means, and drive means for rotatably driving the rotor of said oscillator means so as to set up lateral resonant standing wave vibrations of the resonant bar means, whereby resonant energy is transferred from said bar means to said cutter blade means in unidirectional pulses so as to vibrationally drive the cutting edge of said cutter means against the earthen material with arcuate vibration as the cutter blade drive means simultaneously drives the cutter blade means rotatably.

Claim 8

In an earth auger having cutter blade means and drive means for driving said cutter blade means around a centrally positioned axis, the improvement wherein means are provided to sonically drive said blade means unidirectionally with arcuate motion along the extended cutting edge of said blade means comprising: resonant bar means comprising at least a pair of longitudinal bars positioned opposite each other, means for supporting the longitudinal bars on said drive means for rotation therewith, said resonant bar means being supported with a vibratory energy delivering portion thereof in proximity to a face of said cutter blade means opposite to the cutting edge thereof, said cutter blade drive means comprising a central stem, said cutter blade means comprising a cutter blade associated with each of said bars, said cutter blades being attached at one end thereof to said stem and extending laterally away from said stem, said bars being positioned near the ends of the cutter blades opposite said one ends thereof, a mechanical oscillator having an orbiting rotor connected to said resonant bar means, and drive means for rotatably driving the rotor of said oscillator means so as to set up lateral resonant standing wave vibrations of the resonant bar means, whereby resonant energy is transferred from said bar means to said cutter blade means in unidirectional pulses so as to vibrationally drive the cutting edge of said cutter means against the earthen material with arcuate vibration as the cutter blade drive means simultaneously drives the cutter blade means rotatably.