A Novel Buckling Configuration: Rigid-Outer / Flexible-Inner Cantilevered Fan with Constrained Inward Buckling

A multi-layer cantilevered fan configuration is described in which two rigid outer cards constrain two flexible inner cards to buckle inward (toward each other) under sideways compression, forming a U-shaped cooperative deformation that provides progressive resistance. The configuration is not found in standard mechanical engineering literature or patent databases. This note documents the configuration for prior art and timestamp purposes.