| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a connection anchor structure having large fastening strength with relatively short length of a connection anchor. <P>SOLUTION: A cylindrical connection anchor made of metal is provided with a screw hole for screwing a bolt along the center axis of the cylindrical body of the anchor from the top face to the vicinity of the central part. The outside surface of the anchor is provided with two to five annular concave grooves spaced apart from each other. The outside surface of the anchor except for the annular concave grooves is provided with knurling. Preferably the screw hole for screwing a bolt has a diameter of 10 mm to 24 mm. Preferably the anchor has an outer diameter of 14 mm to 36 mm, and a length of 30 mm to 200 mm. A plastic cap for the connection anchor is provided with an external threaded projection to be screwed into the screw hole for screwing a bolt on the down side of a disk-like collar part, opening on the top face of the anchor body, and a projection for screwing the cap in and out on the upper side. <P>COPYRIGHT: (C)2013,JPO&INPIT |
