SELF-DRILLING SCREW Russian patent published in 2013 - IPC F16B25/10 

FIELD: construction.

SUBSTANCE: self-drilling screw is described with a drilling part installed on the free end of a screw rod, from the drilling part two wings stretch radially, and their border surface facing the drilling tip of the drilling part is made in the form of a cutting edge. The drilling part has a zone of chips removal formed by the fact that the border surface of the wings facing the drilling tip forms a crossing point with a boring radius. The crossing point has at least one gap to the screw rod, which corresponds to 2/3 of the length of the cutting edge of the drilling tip. Availability of the chips removal zone makes it possible to remove chips produced under the cutting edge (on the drilling tip) without hindrances and jams. The material removed by the cutting edge in the form of chips during the drilling process is removed due to rotary motion of a screw from the drilling tip in direction of the crossing point in the lower area of wing adjacency, and therefore free removal of chips is ensured. It is possible to compact chips intended for removal by maximum of 2/3 from the cross section produced after drilling.

EFFECT: possibility to remove chips critical in mass from a drilling part area without blocking of a chips removal process.

10 cl, 7 dwg