ATTACHED COUNTERSINKING APPARATUS Russian patent published in 2006 - IPC B23B51/10 

FIELD: machining of parts, countersinking and counterboring of end surfaces from reverse side.

SUBSTANCE: countersinking apparatus has casing with cutting teeth and seating aperture for mounting on mandrel and is further equipped with device for holding on mandrel before beginning of countersinking process. Mandrel used is drill equipped with helical groove and positioned for axial displacement within aperture of countersinking apparatus. The latter is furnished with stop provided in side wall of casing with outlet oriented toward said aperture so as to cooperate with helical groove of drill and restricting device for restricting axial displacement of drill along straight path within aperture of countersinking apparatus, said device being made in the form of base body overlapping base aperture. Annular groove is provided through casing aperture wall. Device for holding of countersinking apparatus on drill is made in the form of springy ring located within groove so as to be released. Outer diameter of springy ring in its free state exceeds diameter of aperture, and inner diameter of ring is smaller than diameter of drill.

EFFECT: increased efficiency by reducing the number of intermediate operations.

2 dwg