Percussion drilling system

Claim 2

A percussion drilling apparatus comprising: a drilling mass having a fundamental damped vibrational frequency; means for elastically biasing the drilling mass into engagement with a formation to be drilled; driver means for reciprocating the drilling mass toward the formation at a rate substantially equal to its fundamental damped vibrational frequency; and fluid means for actuating the driver means to reciprocate the drilling mass.

Claim 3

A prime mover apparatus for drilling purposes comprising: a drilling mass; elastic restoring means for cooperation with the drilling mass to provide a natural damped period of oscillation of the drilling mass, and for biasing the drilling mass toward a formation to be drilled; fluid powered hammer means for reciprocating the drilling mass toward the formation at a frequency substantially identical to the natural damped period of oscillation of the drilling mass; and valving means for regulating the operation of the fluid powered hammer means.

Claim 4

A prime mover apparatus for drilling purposes comprising: a drilling mass; elastic restoring means for cooperation with the drilling mass to provide a natural damped period of oscillation of the drilling mass, and for biasing the drilling mass toward a formation to be drilled; fluid powered hammer means for reciprocating the drilling mass toward the formation at a frequency substantially identical to the natural damped period of oscillation of the drilling mass; and valving means for regulating the operation of the fluid powered hammer means.

Claim 5

A forced resonant harmonic prime mover apparatus for borehole drilling comprising: a reciprocal drilling mass; means for elastically restoring the mass to provide a natural damped period of oscillation of the mass and for biasing the drilling mass toward a formation to be drilled; means for reciprocating the drilling mass relative to the formation at a frequency substantially equal to the natural period of oscillation of the mass; and fluid means for actuating the means for reciprocating the drilling mass at a frequency substantially equal to the natural period of oscillation of the drilling mass and thereby reinforcing the movement of the mass to increase the amplitude of oscillation of the mass.

Claim 6

A forced resonant harmonic prime mover apparatus for borehole drilling comprising: a reciprocal drilling mass; means for elastically restoring the mass to provide a natural damped period of oscillation of the mass and for biasing the drilling mass toward a formation to be drilled; means for reciprocating the drilling mass relative to the formation at a frequency substantially equal to the natural period of oscillation of the mass; and fluid means for actuating the means for reciprocating the drilling mass at a frequency substantially equal to the natural period of oscillation of the drilling mass and thereby reinforcing the movement of the mass to increase the amplitude of oscillation of the mass.

Claim 7

A forced resonant harmonic prime mover for borehole drilling according to claim 3 wherein the means for elastically restoring the drilling mass includes means for applying a separate force directed along the axis of oscillation of the drilling mass and thereby superimposing the oscillation forces of the drilling mass on the separate force.

Claim 8

The prime mover according to claim 4 wherein the means for reciprocating the drilling mass includes a reciprocal hammer powered in both directions of reciprocation by fluid under pressure.

Claim 9

A percussion drilling apparatus comprising: a down hole reciprocatory percussion motor; a drilling bit mounted for outward reciprocation by the percussion motor to form a borehole in the earth; a drill string for supporting the percussion motor and the drilling bit and for applying an outwardly directed force; and spring means mounted between the drill string and the drilling bit for applying the drill string force to the drilling bit during the outward reciprocation of the bit by the percussion motor so that the outwardly directed force of the percussion motor is superimposed on the outwardly directed force of the drill string to increase the drilling action of the bit.

Claim 10

A percussion drilling apparatus comprising: a down hole reciprocatory percussion motor; a drilling bit mounted for outward reciprocation by the percussion motor to form a borehole in the earth; a drill string for supporting the percussion motor and the drilling bit and for applying an outwardly directed force; and spring means mounted between the drill string and the drilling bit for applying the drill string force to the drilling bit during the outward reciprocation of the bit by the percussion motor so that the outwardly directed force of the percussion motor is superimposed on the outwardly directed force of the drill string to increase the drilling action of the bit.

Claim 11

The percussion drilling system according to claim 6 wherein the percussion motor reciprocates the drilling bit at a predetermined frequency and wherein the means for applying the force of the drill string to the drilling bit comprises at least one elastic element mounted between the drill string and the drilling bit for cooperation with the formation of the earth to oscillate the drilling bit at a frequency substantially identical to the predetermined frequency of operation of the percussion motor.

Claim 12

The percussion drilling system according to claim 7 wherein the percussion motor comprises an anvil slidably supported at the distal end of the drill string and having the drilling bit secured thereto, a hammer mounted for reciprocation into and out of engagement with the anvil, and valving means for alternately directing fluid pressure supplied through the drill string to the opposite sides of the hammer and thereby causing alternate inward and outward reciprocation of the hammer.

Claim 13

The percussion drilling system according to claim 8 wherein the valving means comprises a valving member mounted on the hammer for movement with respect thereto under its own inertia to a first valving position whenever the hammer reaches one extreme of its reciprocation and for movement under its own inertia to a second valving position whenever the hammer reaches the other extreme of its reciprocation, and means for moving the hammer toward the anvil whenever the valving member is in the first valving position and for moving the hammer away from the anvil whenever the valving member is in the second valving position.

Claim 14

The percussion drilling system according to claim 8 wherein the valving means comprises a member extending from the drill string through the hammer to the anvil and having pressurized fluid inlet and exhaust fluid outlet passages formed in it, and a pair of passageways formed through the hammer, the first extending to one end of the hammer and including a portion located for communication with the inlet passageway when the hammer is at one extreme of its reciprocation and for reciprocation with the outlet passageway when the hammer is at the other extreme of its reciprocation, and the second extending to the opposite end of the hammer and including a portion located for communication with the inlet passageway when the hammer is at one extreme of its reciprocation and a portion located for communication with the outlet passageway when the hammer is at the other extreme of its reciprocation.

Claim 15

A percussion drilling system comprising: a drilling bit for penetrating a formation of the earth in a predetermined direction; drill string means providing a force having the predetermined direction; means for reciprocating the drilling bit relative to the drill string means; and means mounted between the drill string means and the drilling bit for transferring the drill string force energy to the drilling bit inphase with the movement of the bit toward the formation under the action of the reciprocating means.

Claim 16

A percussion drilling system comprising: a drilling bit for penetrating a formation of the earth in a predetermined direction; drill string means providing a force having the predetermined direction; means for reciprocating the drilling bit relative to the drill string means; and means mounted between the drill string means and the drilling bit for transferring the drill string force energy to the drilling bit inphase with the movement of the bit toward the formation under the action of the reciprocating means.

Claim 17

The percussion drilling system according to claim 11 wherein the force energy transferring means further comprises means for storing energy from the force of the drill string during movement of the bit toward the drill string.

Claim 18

The percussion drilling system according to claim 12 wherein the force energy transferring means comprises at least one spring mounted between the drill string means and the drilling bit and having such a spring constant that the formation of the earth and the spring cooperate to restore the drilling bit substantially inphase with the movement of the drilling bit reciprocating means.

Claim 19

The percussion drilling system according to claim 13 wherein the drilling bit reciprocating means comprises a percussion motor mounted in the distal end of the drill string and including a hammer which is reciprocated both inwardly and outwardly relative to the drill string means under the action of fluid pressure.

Claim 22

The system according to claim 15 wherein the means for cooperation with the formation being drilled and the anvil-bit mass includes means for applying the force of the drill string and thereby superimposing the anvil-bit mass oscillation forces on the force of the drill string.

Claim 23

The system according to claim 16 wherein the drill string provides an outwardly directed force and wherein the means for cooperation with the formation being drilled and the anvil-bit mass includes means for storing the force energy of the drill string during inward oscillation of the anvil-bit mass and transferring the force energy of the drill string to the anvil-bit mass simultaneously with the outward oscillation of the anvil-bit mass and thereby changing the phase of energy application from the drill string to the anvil-bit.

Claim 24

The percussion drilling system according to claim 15 wherein the means for reciprocating the anvil-bit mass includes a reciprocating hammer and wherein the anvil-bit mass oscillating means comprises at least one spring mounted between the drill string and the anvil-bit mass which in combination with the formation being drilled forms a combined elastic system that functions to substantially return the anvil-bit mass to a predetermined location in a prescribed period of time with a predetermined direction of movement.

Claim 25

The drilling system according to claim 18 further comprising an anvil as part of the bit mass for impact by the hammer and wherein the hammer is driven in both directions of its reciprocation by fluid pressure which is supplied through the drill string.

Claim 26

A percussion drilling system according to claim 19 wherein the drilling anvil-bit mass is retained in one directional longitudinal movement with the drill string by a retainer in the groove of the drilling mass having an outer surface larger than the reduced internal surface of the drill string and having a surface that coacts with the reduced internal surface of the drill string so that when said surfaces are forced together said surfaces will forcibly keep the retainer in the groove of the drilling anvil-bit mass.

Claim 27

The borehole drilling system according to claim 15 wherein the anvil-bit reciprocating means comprises a hammer mounted for reciprocation into and out of engagement with the anvil-bit and valving means for alternately directing fluid pressure supplied through the drill string to the opposite sides of the hammer and thereby causing alternate inward and outward reciprocation of the hammer.

Claim 28

The borehole drilling system according to claim 21 wherein the valving means comprises a valving member mounted on the hammer for movement with respect thereto under its own inertia to a first valving position whenever the hammer reaches one extreme of its reciprocation and for movement under its own inertia to a second valving position whenever the hammer reaches the other extreme of its reciprocation, and means for moving the hammer toward the anvil-bit whenever the valving member is in the first valving position and for moving the hammer away from the anvil-bit whenever the valving member is in the second valving position.

Claim 29

The borehole drilling system according to claim 21 wherein the valving means comprises a member extending from the drill string through the hammer to the anvil-bit and having pressurized fluid inlet and exhaust fluid outlet passages formed in it, and a pair of passageways formed through the hammer, the first extending to one end of the hammer and including a portion located for communication with the inlet passageway when the hammer is at one extreme of its reciprocation and for reciprocation with The outlet passageway when the hammer is at the other extreme of its reciprocation, and the second extending to the opposite end of the hammer and including a portion located for communication with the inlet passageway when the hammer is at one extreme of its reciprocation and a portion located for communication with the outlet passageway when the hammer is at the other extreme of its reciprocation.

Claim 30

A drilling prime mover consisting of: an anvil-bit mass; pipe means supporting the anvil-bit mass; means mounted between the pipe means and the anvil-bit mass for cooperation with the formation being drilled and the anvil-bit mass to cause oscillation of the anvil-bit mass at its fundamental damped vibrational frequency; and means for periodically impulsively forcing the anvil-bit in its direction of movement during oscillation to increase the amplitude of anvil-bit oscillation.

Claim 31

A drilling prime mover consisting of: an anvil-bit mass; pipe means supporting the anvil-bit mass; means mounted between the pipe means and the anvil-bit mass for cooperation with the formation being drilled and the anvil-bit mass to cause oscillation of the anvil-bit mass at its fundamental damped vibrational frequency; and means for periodically impulsively forcing the anvil-bit in its direction of movement during oscillation to increase the amplitude of anvil-bit oscillation.

Claim 32

The prime mover according to claim 24 wherein the pipe means provides a force and the means mounted between the pipe means and the anvil-bit mass for cooperation with the formation being drilled and the anvil-bit mass includes means for transferring the force of the pipe means so that the oscillation forces of the anvil-bit are superimposed on the force of the pipe means.

Claim 33

The prime mover according to claim 24 wherein means mounted between the pipe means and the anvil-bit mass is an elastic member that biases the pipe means and the anvil-bit mass in opposite directions.

Claim 36

The method according to claim 27 wherein the step of forcing the bit outwardly from the drill string is carried out by repeatedly actuating the bit with a percussion motor.

Claim 37

The method according to claim 28 wherein the step of forcing the drilling bit outwardly from the drill string is further characterized by repeatedly impacting an anvil connected to the drilling bit with a reciprocatory hammer which is actuated by fluid pressure supplied through the drill string.

Claim 38

The method according to claim 27 wherein the bit has a natural period of oscillation and further characterized by forcing the bit outwardly at a frequency substantially equal to the natural period of oscillation of the bit.

Claim 41

The method of percussion drilling according to claim 31 wherein the oscillating step is carried out by biasing the drilling bit with a spring which cooperates with a formation to be drilled to oscillate the drilling bit at said natural period of oscillation.

Claim 42

The method of percussion drilling according to claim 32 including the additional step of storing energy in said spring and transferring energy from said spring to the drilling bit during outward reciprocation of the drilling bit.

Claim 43

The method of percussion drilling according to claim 33 wherein the impacting step is carried out by impacting the bit with a reciprocating hammer which is driven both into and out of engagement with the drilling bit under the action of fluid pressure.

Claim 46

The method of drilling a borehole according to claim 35 including the additional step of adding additional energy to the oscillating mass by forcing the mass along the axis of oscillation.

Claim 47

A method of drilling a borehole according to claim 36 wherein the step of periodically adding energy to the oscillating mass is carried out by the percussive impact of a reciprocal hammer driven in both directions of reciprocation by pressurized fluid.

Claim 48

A percussion drilling apparatus comprising: a drill string forming a pressurized fluid inlet passageway; an anvil-bit slidably supported at the distal end of the drill string and including a fluid discharge passageway; means forming a cylinder adjacent the anvil-bit; a piston mounted in the cylinder for reciprocation therein into and out of engagement with the anvil-bit; said piston having at least two passageways formed through it, the first extending into communication with the portion of the cylinder beneath the piston and the second extending into communication with the portion of the cylinder above the piston; fluid inlet means for directing pressurized fluid from the drill string to a pressurized fluid outlet opening; and fluid outlet means for directing exhaust fluid from an exhaust fluid inlet opening to the fluid discharge passageway of the anvil-bit, valving means responsive to positioning of the piston in the lower portion of the cylinder to connect the pressurized fluid outlet opening in communication with the first passageway in the piston to direct pressurized fluid to the portion of the cylinder beneath the piston and to connect the exhaust fluid inlet opening in communication with the second passageway in the piston to direct exhaust fluid from the portion of the cylinder above the piston into the fluid discharge passageway of the anvil-bit and responsive to positioning of the piston in the upper portion of the cylinder to connect the pressurized fluid outlet opening in communication with the second passageway in the piston to direct pressurized fluid to the portion of the piston above the cylinder and to connect the exhaust fluid inlet opening in communication with the first passageway in the piston to direct exhaust fluid from the portion of the cylinder beneath the piston into the fluid discharge passageway of the anvil-bit.

Claim 49

A percussion drilling apparatus comprising: a drill string forming a pressurized fluid inlet passageway; an anvil-bit slidably supported at the distal end of the drill string and including a fluid discharge passageway; means forming a cylinder adjacent the anvil-bit; a piston mounted in the cylinder for reciprocation therein into and out of engagement with the anvil-bit; said piston having at least two passageways formed through it, the first extending into communication with the portion of the cylinder beneath the piston and the second extending into communication with the portion of the cylinder above the piston; fluid inlet means for directing pressurized fluid from the drill string to a pressurized fluid outlet opening; and fluid outlet means for directing exhaust fluid from an exhaust fluid inlet opening to the fluid discharge passageway of the anvil-bit, valving means responsive to positioning of the piston in the lower portion of the cylinder to connect the pressurized fluid outlet opening in communication with the first passageway in the piston to direct pressurized fluid to the portion of the cylinder beneath the piston and to connect the exhaust fluid inlet opening in communication with the second passageway in the piston to direct exhaust fluid from the portion of the cylinder above the piston into the fluid discharge passageway of the anvil-bit and responsive to positioning of the piston in the upper portion of the cylinder to connect the pressurized fluid outlet opening in communication with the second passageway in the piston to direct pressurized fluid to the portion of the piston above the cylinder and to connect the exhaust fluid inlet opening in communication with the first passageway in the piston to direct exhaust fluid from the portion of the cylinder beneath the piston into the fluid discharge passageway of the anvil-bit.

Claim 50

A percussion drilling system according to claim 38 wherein the fluid inlet means and the fluid outlet means comprise passageways formed in a member mounted in the cylinder and extending from the drill string through the hammer to the anvil-bit.

Claim 51

The percussion drilling system according to claim 39 further including a reduced diameter passageway extending through the member from the passageway in the member comprising the fluid inlet means to the passageway in the member comprising the fluid outlet means for providing continuous fluid flow through the fluid discharge passageway of the anvil-bit while maintaining a pressure differential between the fluid inlet passageway of the drill string and the fluid discharge passageway of the anvil-bit.

Claim 52

The percussion drilling system according to claim 40 wherein at least portions of the passageways in the piston are formed in a valve block mounted in the piston for reciprocation therewith.

Claim 53

In a percussion drilling system of the type including an anvil-bit having a fluid discharge passageway formed through it, a hammer mounted for reciprocation into and out of engagement with the anvil-bit, and a drill string for supporting the anvil-bit and the hammer and having a pressurized fluid inlet passageway formed through it, the improvement comprising: a member extending from the drill string through the hammer to the anvil-bit, said member having a pressurized fluid passageway extending through it from the pressurized fluid inlet passageway in the drill string to a pressurized fluid outlEt opening and having an exhaust fluid passageway extending through it from an exhaust fluid inlet opening to the fluid discharge passageway in the anvil-bit; and two passageways formed through the hammer, the first extending to one end of the hammer and including a portion located for communication with the pressurized fluid outlet opening when the hammer is at one extreme of its reciprocation and another portion located for communication with the exhaust fluid inlet opening when the hammer is at the other extreme of its reciprocation, and the second extending to the opposite end of the hammer and including a portion located for communication with the pressurized fluid outlet opening when the hammer is at one extreme of its reciprocation and another portion located for communication with the exhaust fluid inlet opening when the hammer is at the other extreme of its reciprocation.

Claim 54

In a percussion drilling system of the type including an anvil-bit having a fluid discharge passageway formed through it, a hammer mounted for reciprocation into and out of engagement with the anvil-bit, and a drill string for supporting the anvil-bit and the hammer and having a pressurized fluid inlet passageway formed through it, the improvement comprising: a member extending from the drill string through the hammer to the anvil-bit, said member having a pressurized fluid passageway extending through it from the pressurized fluid inlet passageway in the drill string to a pressurized fluid outlEt opening and having an exhaust fluid passageway extending through it from an exhaust fluid inlet opening to the fluid discharge passageway in the anvil-bit; and two passageways formed through the hammer, the first extending to one end of the hammer and including a portion located for communication with the pressurized fluid outlet opening when the hammer is at one extreme of its reciprocation and another portion located for communication with the exhaust fluid inlet opening when the hammer is at the other extreme of its reciprocation, and the second extending to the opposite end of the hammer and including a portion located for communication with the pressurized fluid outlet opening when the hammer is at one extreme of its reciprocation and another portion located for communication with the exhaust fluid inlet opening when the hammer is at the other extreme of its reciprocation.

Claim 55

The improvement according to claim 42 wherein the pressurized fluid passageway and the exhaust fluid passageway of the member are of relatively large diameter and further including a relatively small diameter passageway extending through the member from the pressurized fluid passageway to the exhaust fluid passageway for permitting constant fluid flow through the exhaust fluid passageway to the fluid discharge passageway of the anvil-bit while maintaining a predetermined pressure differential between the pressurized fluid passageway and the exhaust fluid passageway.

Claim 56

The improvement according to claim 43 wherein the pressurized fluid outlet opening and the exhaust fluid inlet opening are outwardly facing and wherein the portions of the passageways of the hammer located for communication with the pressurized fluid inlet opening and the exhaust fluid outlet opening are inwardly facing so that sliding valve action is effected during reciprocation of the hammer.

Claim 57

For use in a percussion drilling apparatus, an anvil-bit having a mass which cooperates with elastic restoring forces to establish a natural period of oscillation of the anvil-bit and having a drilling bit on one end thereof, an anvil on the opposite end thereof, a shank diameter smaller than the bit extending from the anvil end, rotational drive surfaces on said shank, a retainer groove near said anvil end on said shank, fluid passageway through said anvil, shank, and bit and a substantially radially surface connecting the outside of the shank surface with an enlarged diameter of the anvil-bit mass extending from the drilling bit end toward the anvil end and adapted to receive the application of said elastic restoring forces.

Claim 58

For use in a percussion drilling apparatus, an anvil-bit having a mass which cooperates with elastic restoring forces to establish a natural period of oscillation of the anvil-bit and having a drilling bit on one end thereof, an anvil on the opposite end thereof, a shank diameter smaller than the bit extending from the anvil end, rotational drive surfaces on said shank, a retainer groove near said anvil end on said shank, fluid passageway through said anvil, shank, and bit and a substantially radially surface connecting the outside of the shank surface with an enlarged diameter of the anvil-bit mass extending from the drilling bit end toward the anvil end and adapted to receive the application of said elastic restoring forces.