Self-Locking Micro Threaded Fastener With Helical Edge Contact

The patent applies asymmetry by modifying the thread profile from a symmetric standardized form to an asymmetric custom profile. The asymmetric thread profile creates a larger contact surface area between the screw and nut threads, distributing the tightening forces over multiple points rather than concentrating them at a single point. This asymmetric design maintains ease of manufacture while improving tightening stability and preventing loosening under shock or vibration.

The patent applies self-service by designing a thread profile that inherently provides self-locking capability through its asymmetric geometry. The modified thread profile creates friction and mechanical interference that automatically prevent loosening without requiring external locking mechanisms or chemical adhesives. This eliminates the need for additional gluing operations, maintaining reliability while simplifying the assembly process.

The patent applies local quality by modifying only the critical local geometry of the thread profile where contact occurs, rather than requiring high precision throughout the entire thread. The asymmetric thread profile is designed with specific local features that create the self-locking effect, while other portions of the thread can be manufactured with standard tolerances. This approach achieves tightening stability without requiring very difficult machining precision in small modules.