Abstract: The phenomena of sliding and loosening due to vibration exist extensively in engineering. In order to found the mechanical principle of preventing sliding and loosening due to vibration, and thus further analyse and slove the problems of sliding and loosening in working condition of vibration, we advance tine conception of dynamic self-locking, found the theory of dynamic self-locking, and treat upon them by emphatically connecting the application in mechanical engineering. It will be hopeful that this principle can offer a new content for dynamic design of the machine.

Key words: Dynamic self-locking, Loosening due to vibration, Sliding due to vibration