Patent ID: 8733743

Claim:
A gas spring piston dimensioned to receive an open end of an associated flexible wall, said gas spring piston comprising: a piston body having a longitudinal axis and including: a first piston end; a second piston end spaced longitudinally from said first piston end; a first side wall extending circumferentially about said axis and longitudinally between said first and second piston ends; an end wall extending transverse to said axis and interconnecting with said first side wall; and, a second side wall extending circumferentially about said axis and projecting longitudinally from said end wall in a direction opposite said first side wall, said second side wall including an outer surface and a retainment ridge disposed in longitudinally-spaced relation to said end wall such that said outer surface is disposed between said retainment ridge and said end wall, said retainment ridge projecting radially-outwardly beyond said outer surface such that a shoulder surface is formed adjacent said outer surface and extends radially-outwardly along said retainment ridge in approximate alignment with said end wall, said outer surface including an engagement feature dimensioned to compressively engage an end surface of the associated flexible wall, said engagement feature being positioned along said outer surface in longitudinally-spaced relation to said end wall and said shoulder surface of said retainment ridge, wherein said engagement feature includes a groove extending radially-inwardly into said second side wall, said outer surface includes a first surface portion disposed between said end wall and said engagement feature, a second surface portion disposed between said shoulder surface and said engagement feature, and a third surface portion disposed between said first and second surface portions with said third surface portion at least partially defining said groove of said engagement feature, and wherein said third portion includes a curvilinear cross-sectional profile extending into said second side wall in a concave orientation and at least partially forms said groove of said engagement feature, and wherein said first and second surface portions have a linear cross-sectional profile and extend respectively between said end wall and said engagement feature and said shoulder and said engagement feature, said first, second and third surface portions defining the entirety of said outer surface between said shoulder surface and said end wall.