Tubular window frame plastic connection joint - has serrated corner surface and elastically deformabable gusseted sides

摘要

The tough plastic angle (1) is used as a joint between the tubular metal pieces of a composite window frame. The piece has two flat sides (4,5) at right angles, and each side has reinforcing webs (6,7). Convex deformable gussets (11,12, 13,14) span the webs and offer frictional resistance to sliding between the tubes and the angle. Shallow rectangular grooves (9) in the inside face of each side, limit the travel of the tubes along the angle, as the edge of the tube butts against the groove. The outside edge of the angle is serrated (15) at the bend to provide a key for mastic sealant.