| 摘要 |
<p>A key-operated security lock of the kind including a key-identification mechanism, a thrower turned by the key and a deadbolt, has the deadbolt isolated from the thrower, and includes means operable only by correct identification of the key for connecting the thrower to the deadbolt and for removing a stop preventing retraction of the deadbolt from its extended position. The said means preferably includes a lever pivoted to the deadbolt and formed with a locking projection capable of engagement with a complementary recess in a runner driven along a path parallel with that of the bolt by co-operation with the thrower to connect the thrower to the deadbolt as a result of pivoting of the lever which is prevented by a further member in the form of a pivoted arm which holds the pivoted lever in a position such that its locking projection is clear of its recess until the pivoted arm is allowed to turn by the key-identification mechanism. The key-identification mechanism may comprise detainers having slots which, when a correct key is employed, are lined up to allow the entry of a probe which, in its turn, allows movement of the pivoted arm and the thrower may be formed with a cam which holds the pivoted arm in a position such that the probe is clear of the detainers of the key-identification mechanism until the thrower reaches an angular position in which the slots are lined up by the use of a correct key.</p> |
