Swivel/tilting bit crown for earth-boring drills

A bit for use in earth boring at a distal end of a drill string, said bit comprising:

• a shank for attachment of said bit to the end of a drill string;
• lugs extending from said shank to rotate therewith for transmitting torque;
• and
• a crown movably engaged with said lugs to rotate therewith and adapted to tilt with respect to said shank for cutting an earth formation;
• said crown including a plurality of cutting elements disposed thereon for cutting said earth formation, and said tilt adaption of said crown affording substantially continuous engagement of said cutting elements with said earth formation.

A system for drilling a formation in the earth, said system comprising:

• a drill string for selective rotation in a borehole;
• a downhole prime mover attachable to said drill string and having an output shaft;
• a bit attachable to said drill string for cutting a formation to a gage diameter, said bit comprising:
• a connection element for attaching said bit to said downhole prime mover output shaft;
• and
• a crown having cutting elements mounted thereon, at least one of which cutting elements is diposed to cut said gage diameter, for cutting said formation, said crown being tiltably secured to said connection element for substantially continuous contact of said cutting elements with the bottom of said borehole;
• and
• a guide assembly for orienting said output shaft of said downhole prime mover at an angle to said drill string.

A drill bit for drilling a borehole in subterranean formations, comprising:

• a shank for attaching said drill bit to a drill string;
• a crown having an exterior including a face extend radially outwardly from a center to gage, said gage defining the diameter of said borehole;
• a plurality of cutting elements carried on said face of said crown, said cutting elements being disposed over said face to and including said gage;
• and
• a tilting assembly immediately adjacent said crown, said tilting assembly permitting tilting of said crown with respect to said shank while transmitting torque and axial loads from said drill string through said shank and to said crown;
• said tilting assembly being comprised of:
• at least one drive element attached to said shank and rotatable therewith;
• at least one lug pivotably secure to said at least one drive element and rotatable with said at least one drive element;
• and
• at least one way associated with said crown for receiving said at least one lug in substantially axial sliding engagement therewith.

A drill bit for drilling a borehole in substance formations, comprising:

• a shank for attaching said drill bit to a drill string;
• a crown having an exterior including a face extending radially outwardly from a center to gage, said gage defining the diameter of said borehole;
• a plurality of cutting elements carried on said face of said crown, said cutting elements being disposed over said face to and including said gage;
• and
• a tilting assembly immediately adjacent said crown, said tilting assembly permitting tilting of said crown with respect to said shank while transmitting torque and axial loads from said drill string through said shank and to said crown;
• said tilting assembly being comprised of:
• circumferentially-spaced lugs disposed about said shank;
• and
• circumferentially-spaced ways in said crown for receiving said lugs in fixed rotational and sliding axial engagement therewith.