Patent ID: 8375529

Claim:
A touch fastener comprising a first portion for attaching to a second portion, said first portion including a generally thin shell structure comprising a continuous undulating three-dimensionally shaped sheet of generally uniform thickness with: a plurality of protrusions with generally convex sidewalls, each protrusion having bilaterally undercut edges with undersides coincident with a meeting plane, said edges arcuately arching away from a longitudinal axis, said edges separated by a first stem and a second stem, each stem contiguous with said sidewalls and extending below said meeting plane; a receptor between each laterally adjacent pair of said protrusions, said receptor bounded laterally by at least said first stems, bounded vertically by said undersides of adjacent said undercut edges, and bounded longitudinally by at least one next proximate stem wall associated with a next proximate protrusion of a longitudinally adjacent row; and a receptor opening, longitudinally offset from said receptor, coincident with said meeting plane, extending between said undercut edges of adjacent protrusions and said at least one next proximate stem wall; said protrusions and said receptor configured so that: the depth of said receptor below said meeting plane is greater than the height of said protrusions above said meeting plane; the width of said protrusion at said meeting plane between said undercut edges is greater than the gap between the undercut edges of laterally adjacent protrusions, and said gap is at least as great as the width of at least said first stem; said receptor opening is sized to snuggly receive a respective corresponding protrusion associated with said second portion; and said next proximate stem wall is obliquely inclined into said receptor; so that application of a relative compressive force to said first and second portions causes at least one protrusion of said second portion to vertically align with and pass through said receptor opening, and thence shift longitudinally into an interlocking juxtaposition as said generally convex sidewalls interface said obliquely inclined stem walls.