Band Clamp Locking Dimple Forming and Cutting

The patent replaces the conical punch tip with a hemispherical punch tip. This spherical curvature distributes the forming force uniformly across the band material, creating a locking dimple with uniform wall thickness. The uniform geometry eliminates the slip-back problem that occurs with conical tips, as the band walls engage properly with the buckle aperture without creating gaps that lead to force loss.

The patent segments the knife-edge into multiple portions (first, second, and third portions) that cut the band at different times during the reciprocating motion. The first portion cuts initially, followed by the second and third portions completing the cut as the knife continues its motion. This sequential cutting allows the punch sufficient time to fully form the locking dimple before the cut is completed, ensuring maximum lock strength while maintaining manufacturing efficiency.

The patent implements preliminary action by having the punch begin forming the locking dimple before the knife-edge completes the cutting operation. The punch starts deforming the band material early in the reciprocating cycle, and continues to apply force throughout the cutting process. This ensures the locking dimple is fully formed with proper wall thickness and geometry before the band is completely severed, maximizing retained force while maintaining efficient production cycles.