Patent ID: 8206136

Claim:
A system including a diaphragm and co-acting part, comprising: a co-acting part which comprises a stiff outer wall, a first annular protrusion, and a second annular protrusion, wherein the stiff outer wall comprises a generally radially extending portion of the co-acting part having radial protrusions extending therefrom and including the outermost annular wall; and a diaphragm co-acting therewith which comprises a flexible wall of a predetermined shape and thickness, wherein the flexible wall of the diaphragm is movable along the stiff outer wall of the co-acting part, and wherein the diaphragm comprises at least two separately deformable flexible wall parts, wherein a first deformable flexible wall part is sized and configured to co-act with the first annular protrusion and a second deformable flexible wall part is sized and configured to co-act with the second annular protrusion.