Document Type and Number:
Japanese Patent JPH0237487
Kind Code:
B2
Abstract:
1. Cross recessed screw (1) having a forged central hole (5) with a base (8) having a circular cross-sectional area, and preferrably four slots arranged radially around said central hole (5) and staggered by 90 degrees with respect to each other, where the outer wall (6) of the slots forms a part of an inverted truncated cone, which is coaxial with the axis (x-x) of the screw and the base of which lies on the surface of the screw head, as well as having a cylindrical guide zone (7), characterized in that the diameter of the cross-sectional area of the central hole (5) is equal to the diameter of the top face of the truncated cone which is associated with said slots (4) and that there are approximately V-shaped valleys (12) between the slots (4) and that the neighbouring side-walls (9, 10 or 15, 16) of said slots (4) and said valleys (12) form common edges (17) respectively which are located on a cylindrical generated surface whose diameter corresponds to the diameter of said guide zone (7).
Inventors:
ROBERUTO DEITSUKE
Application Number:
JP6756081A
Publication Date:
August 24, 1990
Filing Date:
May 01, 1981
Export Citation:
Assignee:
BORUFUGANGU ERUZENHAIMA
International Classes:
A47G3/00; B25B15/00; F16B23/00; F16B37/14
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