| 摘要 |
A high security-unit-type, door lock having opposite side escutcheon plates which are drawn tightly against the opposite faces of the door by means accessible only from the edge of the door, so that the escutcheon plates cannot be removed when the door is closed. The lock cylinder and plug have longitudinally-spaced, radially-extending, tumbler pins therein, spring biased toward the center of the lock, the plug being formed of body end sections which are relatively rotatable for assembly at 90 DEG incremental positions. The end plugs determine the rotational position in which the key enters the lock whereby four lock combinations are provided for by relative rotation between the ends and body of the plug without changing the lengths of the tumbler pins. The lock plug directly drives bolt-extending means over-center as the plug rotates 90 DEG to prevent the bolt being pushed back into the lock from the exterior thereof. In the 90 DEG , bolt-extended position of the plug, the key may be withdrawn from the lock without rotating the plug back to its original key-insert position. The key may enter the lock from either side, using the same cylinder and tumbler pins, and the key is of cylindrical shape having straight through transverse notches milled in its outer surface spaced 90 DEG about the circumference of the key and spaced longitudinally thereof in accordance with the tumbler pin spacing.
|
