Air spring strut

An air spring strut for mounting between a vehicle axle and a body of a vehicle, the air spring strut comprising:

• a shock absorber including a cylinder, a piston rod having a first end and a second end, a piston connected to said piston rod at said first end thereof and being displaceable in said cylinder;
• an air spring including a cover attached to said vehicle and a roll-off piston supported on said cylinder of said shock absorber;
• said cylinder having a foot point articulately connected to said axle and said second end of said piston rod being pivotally connected to said cover;
• said air spring further including a resilient member clamped between said roll-off piston and said cover and said resilient member forming a rolling lobe during operation of said vehicle;
• said resilient member having an outer surface;
• a bell having an annular side wall enclosing at least a portion of said outer surface of said resilient member and said annular side wall defining a nonlinear center axis;
• said bell being so configured that each cross section thereof has an approximately circular cross-sectional area defining a center point on said axis;
• the center points of all of the cross-sectional areas being disposed along said axis defining approximately a nonlinear path segment over the largest part of the excursion path described by said air spring during deflection thereof;
• said cross-sectional areas having respective diameters which become greater in a direction toward said foot point;
• and,
• said roll-off piston being curved and said axis being a center line of curvature coincident with said curve on which said center points of said cross-sectional areas lie.