Patent ID: 7235018

Claim:
A convoluted boot for sealing an articulatable and plungeable joint, comprising: a flexible polymer material; a first larger collar; a second smaller collar; and a plurality of annular fold units which extend between the first collar and the second collar and which comprise outer folds having two annular flanks forming a fold peak between two fold valleys; wherein the fold units form a first group (A) of at least three annular folds joining the first collar, the diameters of the fold peaks and fold valleys decreasing in the direction from the first collar to the second collar, and a second group (B) of at least two annular folds joining the second collar, the diameters of the fold valleys and the fold peaks of the second group (B) being substantially constant; and wherein the two annular flanks of each of the annular folds of the first group (A) form opposed angles with a radial plane (R 1 ), wherein a smaller angle (β 1 ) is formed by the annular flank pointing towards the second collar and wherein a larger angle (α 1 ) with α 1 ≧(β 1 +25°) is formed by the annular flank pointing towards the first collar, and the annular flanks of each of the annular folds of the first group (A) which point to the first collar are curved so as to be outwardly convex; and wherein a ratio of a diameter (D 1 ) of the fold peak of largest annular fold of the first group (A) to a diameter (D 2 ) of the second collar is ≧2.5.