Extraction device and method
View Patent ↗A stuck drill bit having a KCS shank can be removed using an article with a body structure. The body structure has an opening that fits onto the shank, and an inward-facing surface around the opening is at least partially complementary to the surface of the shank. The surfaces engage sufficiently that rotary manual force is transferred from the inward-facing surface to the surface of the shank.
1. An article of manufacture comprising:
a KCS rotary hammer drill shank comprising a coupling section including a plurality of open-ended slots running parallel to an axis of rotation of said shank defining an extraction structure, said extraction structure comprising:
a body substructure having:
an opening having at least a first portion adapted to fit onto said KCS rotary hammer drill shank coupling section, wherein said first portion comprises an inward-facing surface around the opening, the inward-facing surface is adapted to fit on and slide down said shank with a slideable fit, wherein said inwardly facing surface further comprises a plurality of inward-facing surface having a plurality of apertures, said body substructure further comprising a plurality of spaced apart cavities formed in said body substructure each radially extending away from a center said opening through said body substructure;
a plurality of spring loaded splines each comprising a spring and spline disposed in said plurality of spaced apart cavities where each of said spring loaded splines are configured as laterally moveable splines respectively extending out of said plurality of apertures, wherein some of said splines are respectively biased by said springs to retract or extend such that said splines can extendably fit into at least two of said open-ended slots; and
one or more arm substructures extending radially outward from the body substructure adapted to and formed from a material which permits application of a rotary force through the inward-facing surface to the KCS rotary hammer drill shank or coupling section by application of said rotary force through said splines.
2. A method of using the article of claim 1 with the KCS drill bit stuck in a hole drilled in an object, the method comprising:
placing said extraction structure onto said shank and turning said shank extraction structure in a first rotary direction, fitting the opening in the body substructure onto a KCS drill bit's shank;
rotating said body on said shank until said at least two said splines slideably inserts and engages into at least two said open ended slots due to bias of said springs; and
manually turning at least one of the arm substructures in a second rotary direction opposite the first rotary direction to withdraw the KCS drill bit.
3. The method of claim 2 , further comprising, before the act of fitting the opening onto the KCS drill bit's shank:
rotating in a first direction said KCS drill bit shank and applying a forward hammer force to said KCS drill bit with a drill configured to rotate said KCS drill bit only in said first direction;
removing a KCS drill's chuck coupled to said drill from the KCS drill bit's shank, the KCS drill being non-reversible.