Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
161 words
In a sonic drill for boring into earthen material, an elongated elastic column member, a cutter bit attached to the lower end of said column, said cutter bit having a greater diameter than that of said column so as to permit passage of cuttings alongside the shaft, and a sonic drive unit connected to the other end of said column, said sonic drive unit including a housing, an orbiting mass oscillator supported in said housing, oscillator coupling means for rigidly coupling said oscillator to said column, prime mover means for rotatably driving said oscillator at a frequency such as to set up resonant elastic vibrations of said shaft, and air spring means for providing resilient coupling between said oscillator and said drive unit housing, said air spring means being adapted to provide a restoring force which tends to automatically maintain the relative vertical positioning between said oscillator support means and said housing with variations in the loading on these two components.
Claim 2
Dependent Claim
161 words
In a sonic drill for boring into earthen material, an elongated elastic column member, a cutter bit attached to the lower end of said column, said cutter bit having a greater diameter than that of said column so as to permit passage of cuttings alongside the shaft, and a sonic drive unit connected to the other end of said column, said sonic drive unit including a housing, an orbiting mass oscillator supported in said housing, oscillator coupling means for rigidly coupling said oscillator to said column, prime mover means for rotatably driving said oscillator at a frequency such as to set up resonant elastic vibrations of said shaft, and air spring means for providing resilient coupling between said oscillator and said drive unit housing, said air spring means being adapted to provide a restoring force which tends to automatically maintain the relative vertical positioning between said oscillator support means and said housing with variations in the loading on these two components.
Claim 3
Dependent Claim
74 words
The device of claim 1 wherein said air spring means comprises a plurality of pistons and means for providing pressurized air to the opposite sides of said pistons, vertical relative motion occurring between said pistons and said drive unit housing, and orifice means formed in said housing for permitting air to escape from one side of said pistons to create a pressure differential to restore the pistons and housing to their original relative positions.
Claim 4
Dependent Claim
26 words
The device of claim 1 and additionally including means for vertically guiding and positioning said drive unit so as to minimize lateral movement of said column.
Claim 5
Dependent Claim
19 words
The device of claim 1 and further including means for torsionally rigidly coupling said prime mover to said oscillator.
Claim 6
Dependent Claim
19 words
The device of claim 3 and additionally including means for torsionally rigidly coupling said prime mover to said oscillator.