Structure e.g. trestle, elements locking visualizing device for use during fixation of vehicle wheel, has spring lock washer interposed between two support washers, where one of support washers is directed towards colored visualizing washer

摘要

The device has a spring lock washer (20) e.g. contracted spring lock washer, constituting a mechanical door of the device and interposed between two rigid support washers (8, 9). The washer (8) has a plane lower face (10) and a tapered upper face, and directed towards a visualizing washer (7), which is colored. The washer (8) extends from a passage hole (12) of a screw (5) upto a peripheral end (13) of the visualizing washer to constitute a sliding ramp (11) to facilitate return of the washer (8) towards an initial position during unlocking.