Adjustable ball pin

Claim 1

AN ADJUSTABLE-LENGTH BALL PIN COMPRISING A TUBULAR STEM HAVING A BALL APERTURE AT AN INNER END THEREOF AND A THREADED PORTION AT AN OUTER END OPPOSITE SAID INNER END AND A SMOOTH OUTER CYLINDERICAL SURFACE BETWEEN THE BALL APERTURE AND THE THREADED PORTION, A BALL WITHIN THE APERTURE AND OF SUCH DIAMETER AS TO PROJECT THERETHROUGH, A PLUNGER RECIEVED WITHIN THE TUBULAR STEM HAVING A BALLACCOMMODATING CAM NOTCH ADJACENT TO ITS TIP, THE CAM NOTCH INCLUDING A SHOLLOW PORTION OF SUCH DEPTH AS TO PROJECT THE BALL BEYOND THE OUTER CYLINDRICAL SURFACE AND A PORTION THEREADJACENT OF SUCH DEPTH AS TO PERMIT THE BALL TO RECEDE INWARDLY OF THE CYLINDRICAL SURFACE, THE PLUNGER FURTHER HAVING AN ANNULARLY ENLARGED PORTION ADJACENT ITS OUTER END, SAID PORTION HAVING AN INWARD-FACING ABUTMENT AND AN OUTWARD-FACING ANNULAR SHOULDER, FURTHER COMPRISING A HELICAL SPRING COMPRESSED BETWEEN THE INWARD-FACING ABUTMENT AND THE OUTER END OF THE TUBULAR STEM, AN EXTERNALLY-THREADED SLEEVE OF GREATER OUTER DIAMETER THAN THE PIN AND OF GREATER INNER DIAMETER THAN THE ANNULAR ENLARGEMENT OF THE PLUNGER, THE SLEEVE HAVING AT ITS INNER END INTERNAL THREADS ENGAGING THE THREADED OUTER END OF THE PIN, AND HAVING AT ITS OUTER END AN INWARD-EXTENDING FLANGE TERMINATING IN A CENTRAL BORE IN WHICH THE PLUNGER IS ACCOMMODATED FOR RECIPROCATION AND FORMING AN INWARDLY-PRESENTED ANNULAR SEAT SURFACE AGAINST WHICH THE ANNULAR SHOULDER IS PRESSED BY THE SPRING, FURTHER COMPRISING A HANDLE HAVING AN AXIAL BORE INTERNALLY THREADED TO MATE WITH THE THREADS ON THE EXTERNAL SURFACE OF THE SLEEVE, THE HANDLE HAVING A BOSS TERMINATING IN AN INWARD-FACING ANNULAR ABUTMENT SURFACE, AND MEANS TO RESTRAIN SAID HANDLE FROM INADVERTENT ROTATION.