| 摘要 |
FIELD: mechanical engineering. SUBSTANCE: screw is provided with the axial hollow which can to receive the tip of the wrench whose horizontal projection is a star with six beveled points. The side walls of the hollow are diverging outward and inclined to the axis of the screw at 7-15°. The sides of the beveled points of the star consist of flat surfaces the pairs of which form six answering ribs on the side wall of the hollow. The cross-section of the ribs is a isosceles triangle whose top angle is about 90° and height is about half length of its base. The wrench has the tip mated with the side walls of the screw hollow. EFFECT: enhanced reliability. |
