Reamer for the production of cylindrical fitting holes in workpieces of aluminum - alloys

摘要

The reamer forms a bore for a fitted bolt, particularly in work of aluminium alloy, the rotary tool being fed forward for a set stroke and then returned to the starting position. A gas, vapour or initially liquid cleaning agent is delivered under pressure into the work, emerging into the swarf-chambers of the tool near the latter's tip, so that the fine dust formed is extracted from the bore in the rearwards direction. Spiral cutters (3) extend along the reamer (1), which has to the rear of its cylindrical guide pin (4) a cone friction surface (5) with an angle of less than 10 degrees and of a predetermined length. The cutters extending for this length have a negative rake. The length of the cone surface can be approximately 5 mm and its angle approximately 2 degrees. The negative rake can be roughly 45 degrees, and it can extend for between 0.01 and 0.05 mm.