Cutting tool with an eccentric drive and pinned fastener with de-binding release feature

摘要

A cutting tool assembly having a tool holder and a cutting tool. The cutting tool has a shank that is matingly received within an axial bore in the lower end of the tool holder. The shank includes an eccentrically-shaped driver portion. The tool holder's axial bore includes an enlarged eccentrically-shaped drive opening which is complementary in shape to, but slightly larger than, the driver portion. When the shank is inserted into the axial bore, the driver portion and drive opening are aligned allowing the cutting tool to be partially rotated relative to the tool holder. This partial rotation abuts a portion of the eccentric driver portion against the drive opening wall to provide rigid support of the cutting tool against further rotation as the tool assembly cuts. A cammed fastener releasably interlocks the partially rotated cutting tool within the tool holder.

主权项

1. A tool assembly suited to be removably received into a rotatable spindle of a machine tool, comprising:
a cutting tool having a cutter on one end and a shank on the opposite end, the shank including a eccentrically-shaped drive section having diametrically opposed drive lobes extending radially from a cylindrical drive body, a fastening portion extends axially from the drive section, the fastening portion including an oblong fastening head having diametrically opposed lugs; a tool holder having a generally cylindrical body with an axial opening in one end, the axial opening including a drive wall portion having opposed drive members that extend radially inwardly into the axial opening, whereby each drive lobe abuts one of the drive members when the cutting tool is partially rotated within the axial opening; and a second fastener portion contained within the axial opening and connected to the fastening portion of the cutting tool to axially move the cutting tool toward the tool holder body and telescopically receive the shank within the second end of the tool holder body, wherein the second fastener portion comprises: a retention sleeve having a cylindrical-shaped body sized to be telescopically received within the axial opening, the retention sleeve having a recess in one end which receives the fastening head, the recess being shaped to retain the fastening head axially when the cutting tool is partially rotated and the drive lobes abut the drive members, the retention sleeve including a bore passing perpendicularly there through relative to a longitudinal axis of the retention sleeve; and a camming pin having an tapered cam surface which is rotatable to engage an upper inner surface of the sleeve bore and pull the retention sleeve further into the axial opening.