20100313616 | COMBINATION LOCK CYLINDER - A combination lock cylinder has a shell and multiple external wheels. Multiple resilient ribs are attached respectively in mounting recesses of the shell. Each resilient rib corresponds to one mounting recess and has a central protrusion. Each external wheel has multiple elongated ribs formed transversely out from the outside wall. With the resilient force of the resilient ribs and the interaction between the elongated ribs and the central protrusions, the external wheels are positioned at predetermined positions automatically. | 12-16-2010 |