Abstract: A locking system is utilized to control the locking and unlocking of a lock, such as on a door. The lock includes a magnetic card reader for reading a coded key card into a lock computer which in turn determines functions of and access to the lock. The key card includes a key code, key level code, and key record number stored thereon. The lock includes a memory accessed by the computer which is partitioned and includes a level storage area with level records identified by a lock level code and operational information for the level, and a key storage area for storing lock key records identified by a lock record number and associated with at least one lock level for storing key information associated with the record number. The computer validates a key card by reading and comparing the key level code to the lock level code to determine the level and the key record number to one of the lock record numbers identified with the level in the key storage area.

Abstract: A mortise lock assembly disposed within a housing for mounting in a door. The assembly includes a latch bolt and a dead bolt, both of which are movably mounted within the housing and reciprocal between an extended position cut out of the housing and a retracted position within the housing. The assembly also includes latch bolt and dead bolt biasing mechanism for continuously biasing the latch bolt and dead bolt to their extended positions. The assembly further includes a trigger movably mounted within the housing and a dead bolt stop element movable between a dead bolt engaged position and a released position for restraining the dead bolt in the retracted position against the biasing force of the dead bolt biasing mechanism.

Abstract: A recentering device for a shaft is disclosed which includes a return spring means and a recentering spring. The return spring applies a torque which varies directly with the angular displacement of the shaft from the center position over a predetermined range corresponding to the full operating range of the shaft. The recentering spring means applies a torque which varies inversely with the angular displacement of the shaft over the range of displacement. The maximum torque exerted by the recentering spring means is not substantially greater than the maximum torque exerted by the return spring. The torque exerted by each of the springs is a substantially linear function of angular displacement whereby a substantially uniform value of torque tends to return the shaft to its center position and thereby provides accurate recentering when the shaft is released.