Expanding sleeve, integrated in screw head or nut used in particular in joining of metal parts subject to variable forces

摘要

The screw head or the nut is provided with a sleeve (1) extending from its upper edge and guided downwards first in a curve and then parallel to the outer surface. The lower edge of the sleeve (2) is positioned slightly below a shoulder located at the shaft of the screw. When tension is applied the sleeve is deformed (2) storing energy for a later stage when the connection starts to settle. Shape (3) and material can be adjusted as required by the particular purpose.