A lock nut threadably engageable and lockingly retainable about a threaded shaft extending through a workpiece, the lock nut having at least one deformable slot disposed on a side portion thereof and disposed transversely relative to the lock nut bore axis, the lock nut also having a nut deforming member...http://www.google.es/patents/US5915902?utm_source=gb-gplus-sharePatente US5915902 - Undeformed lock nut with slot
