| 主权项 |
1. An adaptor for holding a threading device to a chuck of a power tool, said adaptor comprising a shank defined by three consecutive flat sides in lateral cross section, wherein said threading device is a tap member having a four sided end, wherein said tap member when rotated will make internal threads within an aperture of a workpiece, and wherein said adaptor further comprises:
a) a first component having a stop ring,
wherein said shank extends centrally from a first side of said stop ring and a cylindrical shaft having four externally threaded jaws extends from a second side of said stop ring,wherein said stop ring is free of any lateral voids and extends only slightly radially outwardly; and b) a second component being an internally threaded collar threads onto said four externally threaded jaws,
wherein when said four sided end of said tap member is inserted between said four externally threaded jaws and said internally threaded collar is tightened on said four externally threaded jaws, said four sided end of said tap member will be grasped by said four externally threaded jaws and held in place; wherein said four externally threaded jaws of said cylindrical shaft define an axial bore; wherein said axial bore defined by said four externally threaded jaws of said cylindrical shaft replaceably receives said tap member; wherein said axial bore defined by said four externally threaded jaws of said cylindrical shaft has a first portion; wherein said axial bore defined by said four externally threaded jaws of said cylindrical shaft has a second portion; wherein said first portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft is coaxial with said second portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft; wherein said first portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft has a cross section; wherein said second portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft has a cross section; wherein said cross section of said first portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft is less than said cross section of said second portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft so as to form a shoulder stop within said four externally threaded jaws of said cylindrical shaft; wherein said first portion of said axial bore defined by said four externally threaded jaws of said cylindrical shaft replaceably receives said four sided end of said tap member, with said shoulder stop within said four externally threaded jaws of said cylindrical shaft having an adjacent portion of said four sided end of said tap member abut thereagainst; wherein said shoulder stop is conical-frustum-shaped thereby smoothly tapering from said second portion of said axial bore to said first portion of said axial bore; wherein said four externally threaded jaws are separated from each other by axial slots; and wherein said axial bore extends further in said cylindrical shaft than does said axial slots. |
