ANNULAR BIT Russian patent published in 2008 - IPC B23B51/04 

FIELD: technological processes.

SUBSTANCE: annular bit pertains to processing materials by cutting and has a hollow case with a cutting end and shank end. The cutting end has cutting teeth and grooves for removing swarf, going into the swarf removal groove of the case. To increase efficiency by increasing the number of teeth, the cutting end is made in form of a ring, rigidly fixed to the hollow case, with projections for interaction with sidewalls of corresponding grooves made on the hollow case. The above mentioned ring had a flat end and overlapping cylindrical base surfaces for interaction with the corresponding flat end and overlapping base surfaces on the hollow case. The cutting end can be joined to the case by soldering or gluing.

EFFECT: obtaining a drill bit which increases efficiency of cutting metal.

2 cl, 4 dwg