A bolt fixing assembly comprises a bolt body, a resilient sleeve, and a pressing member. The bolt body includes a head and a shank. The resilient sleeve includes plural toothed plates integrally formed on an outer periphery thereof. Each resilient toothed plate is initially located in an interior space...http://www.google.de/patents/US6588997?utm_source=gb-gplus-sharePatent US6588997 - Bolt fixing assembly
