LAMINATE WOOD SCREW Russian patent published in 1999 - IPC

FIELD: manufacture of fastening articles, possibly for building, machine engineering and other structures. SUBSTANCE: laminate wood screw includes at least two subareas of materials. At least a part of line of section boundary and(or) at least a part of line of material subareas boundary is in the form of fragment of oblique cone section of straight circular cone. EFFECT: constructionally caused directivity of strength properties, enhanced efficiency of fixation against self-turning off, increased corrosion resistance, easy identification of wood screw maker. 16 cl, 16 dwg