Patent ID: 6514017
Filing Date: 2003-02-04
Classification: B23B,Y10T

Abstract:
A pilot tool assembly for a core drill comprising:a pilot tool unit that includes an elongate mandrel having first and second opposite ends and a pilot tool secured to and projecting from first end of the mandrel, said mandrel having a tapered outer surface characterized by a diameter that increases with increasing distance from second end thereof; and an expandable locking sleeve that surrounds and engages said outer surface of said mandrel, said sleeve being made so that moving it relative to the mandrel in the direction of increasing mandrel diameter will cause the sleeve to expand radially, whereby when said pilot tool assembly is inserted into a core drill said sleeve will engage an inner surface of the core drill and will move axially relative to the mandrel until it has expanded enough to frictionally secure the mandrel to the core drill, thereby making the pilot tool an auxiliary extension of the core drill.