| 摘要 |
FIELD: manufacture of fastening articles, possibly for building, machine engineering and other metallic structures. SUBSTANCE: wood screw includes at least in one cross section of smooth portion of its rod line of section boundary. At least a part of length of line of section boundary is in the form of fragment or combination of fragments of oblique cone section of straight circular cone. EFFECT: constructionally caused directivity of strength properties at operation, enhanced efficiency of fixation against self-turning off in part due to increased lateral surface of wood screw rod smooth portion, easy identification of wood screw maker. 14 cl, 13 dwg |
