Twist drill bit sharpening device

Claim 1

A PORTABLE TWIST DRILL BIT SHARPENING ASSEMBLY FOR OPERATIVE ATTACHMENT TO AN ELECTRIC POWER DRILL HAVING A HOUSING AND A CHUCK, COMPRISING IN COMBINATION, (1) A SUPPORT STRUCTURE (2) A ROTARY GRINDING ELEMENT ON AN AXIALLY ROTATABLE SHAFT CARRIED BY SAID SUPPORT STRUCTURE AND HAVING A GRINDING SURFACE, SAID SHAFT HAVING A FREE END EXTENDING BEYOND A PORTION OF SAID SUPPORT STRUCTURE, (3) A DRILL BIT HOLDER CARRIED BY SAID SUPPORT STRUCTURE PROXIMATE TO SAID GRINDING ELEMENT FOR PRESENTING A DRILL BIT TIP TO BE GROUND IN OPERATIVE GRINDING RELATIONSHIP TO THE SAID GRINDING SURFACE, SAID DRILL BIT HOLDER BEING IN THE FORM OF A ROTARY BIT DIAMETER SIZE SELECTOR MOUNTED FOR ROTATION ABOUT A PART OF SAID SUPPORT STRUCTURE PASSING THERETHROUGH, SAID SELECTOR HAVING A ROTARY WALL PORTION WITH A PLURALITY OF DIFFERENT SPECIFICALLY SIZED APERTURES THERETHROUGH CORREPSPONDING TO THE SIZES OF DIFFERENT DIAMETER BITS