Threaded dowel with cylindrical externally threaded casing - has hollow cylindrical or conical body with cylindrical interior, and has hexagonal head

摘要

The threaded dowel (10) has a shaft with cylindrical, externally-threaded outer casing (14) and a hollow, cylindrical or conical interior (13) with internal thread to take a fixture. The hollow interior (13) has axial ridges or such like and a hexagonal cross-section. The dowel head (11) is also hexagonal, and has a contact flange (24) beneath it. The angle (16, 17) between the thread-flanks (18) of the outer thread (12) is flatter in the front of the threaded dowel (10) than at the back. The flank angle (16, 17) of the thread-flanks (18) becomes continually flatten from the beginning of the outer thread at the back of the dowel to the tip. ADVANTAGE - The thread dowel is better for inserting into foam or other soft materials and is secured against pulling out.