Attachment device for flexible films and fabrics

Claim 1

In a two piece separable device for securely holding flexible material having an inner and an outer surface, the combination comprising complementary inferior male means beneath said inner surface and superior female means above said outer surface which releasably mate together by flex action to capture said material between said means, said male means being provided with an arcuate concave groove opening outward in opposite directions on each of its two outwardly extending sides, one of said grooves being larger than the other with said larger groove being disposed towards the body of said material, and said female means being substantially even and regular in cross-section and having a symmetrical arcuate bead on each edge of its two dependent sides, said beads having a cross-section complementary to the smaller of said concave grooves and said larger groove having sufficient larger size relative to said engaging bead to permit said female means to be rotationally displaced by a tension load placed on said flexible material while being sufficiently small in size to prevent rotational disengagement of said bead due to said tension load, thereby clamping said material between said female and said male means without permitting rotational disengagement of said bead due to said tension load, said grooves and said beads being arranged to engage each other so as to interlock and thereby securely clamp said material between said male and said female means in response to said rotational displacement.