Design of Angular Snap-Fits for Positive Interference Assembly

This article introduces a new design for a cantilever type snap-fit fastener. This new design is configured to provide a positive interference between the mating parts even in the assembled position. The legs are therefore not in a relaxed position at the end of assembly. This results in higher levels of alignment quality and part fit in a completed assembly. The positive interference is achieved by the use of angular legs as opposed to orthogonal legs in a traditional snap-fit. Issues of material strength, fastener geometry, part stiffness, attachment strategy and manufacturability are addressed in the paper.