| 摘要 |
<p>A cylinder lock (10) comprises a shell (14), a core (12), and a plurality of pin tumbler stacks (22, 24). The core includes an outer surface, a keyway and a cut-out offset from, but alignable with, at least one of the tumbler stacks. A plate (34) disposed on the cut-out is movable between a first position, wherein the plate acts as an extension of the core surface to prevent a tumbler stack from entering the cut-out, and a second position, wherein the plate does not prevent a tumbler stack from entering the cut-out. Upon insertion of an authorized key (46) having a projection (58) extending from a side thereof, the projection urges the plate from the second position to the first position to permit the core to rotate to an unlocked position. Upon the insertion of a properly bitted key, but without the projection, only partial rotation is permitted whereupon the tumbler stack enters the cut-out to thereby render the lock inoperable and trap the unauthorized key within the keyway.</p> |
