Expansion bellows with fold enclosing angle - has folds, each with at least one stepped side with saw tooth profile

摘要

At least one side (12,14) of a fold (10) is stepped, when seen in circumferential direction. It has a step (20), which is closed in that direction, and has a saw tooth-shaped profile. The stepped sides are located on the sides of neighbouring folds, which face away from each other. The tips (20') of the saw tooth steps face away from the base (18) of a fold. Both sides of a fold form a step. The inner flank (12') of the step is steeper than the outer flank (12'') which has a weaker wall strength tha the other flank. ADVANTAGE - Automatic return of inward-moved bellows folds.