Combination lock with security feature

A combination lock including a plurality of manually movable rotary combination dials which must each be disposed in a particular orientation in order for the locked to be opened, the particular orientations of the respective combination dials together defining an opening combination of the lock, the dials being mounted in axially adjacent positions on a shaft for rotation about the axis of the shaft, a manual actuator capable of movement from a locked position to an unlocked position only when the dials are disposed in the particular orientations defining said opening combination, and upsetting means for rotating said dials from said particular orientations into other set orientations when the lock is opened, thereby upsetting the opening combination of the lock, said upsetting means including a cam formation on each dial and a cam operator having a follower for each cam formation, the cam operator comprising an elongate member mounted for pivoting movement about an axis parallel to said shaft, the followers comprising arms extending from said elongate member to engage the respective cam formations, and drive means connected between the manual actuator and said cam operator for pivoting said elongate member and causing the arms to cam the dials into their said other set orientations responsive to movement of the manual actuator when the lock is opened, a locking member controlled by the combination dials, and coupling means between the manual actuator and the locking member, and wherein the manual actuator is movable from a first position to a second position, when the combination dials are in the particular orientations to open the lock, for releasing the coupling means, and the manual actuator is movable beyond the second position to operate said drive means.

A combination lock including a plurality of manually movable rotary combination dials which must each be disposed in a particular orientation in order for the locked to be opened, the particular orientations of the respective combination dials together defining an opening combination of the lock, the dials being mounted in axially adjacent positions on a shaft for rotation about the axis of the shaft, a manual actuator capable of movement from a locked position to an unlocked position only when the dials are disposed in the particular orientations defining said opening combination, and upsetting means for rotating said dials from said particular orientations into other set orientations when the lock is opened, thereby upsetting the opening combination of the lock, said upsetting means including a cam formation on each dial and a cam operator having a follower for each cam formation, the cam operator comprising an elongate member mounted for pivoting movement about an axis parallel to said shaft, the followers comprising arms extending from said elongate member to engage the respective cam formations, and drive means connected between the manual actuator and said cam operator for pivoting said elongate member and causing the arms to cam the dials into their said other set orientations responsive to movement of the manual actuator when the lock is opened, a movable locking member controlled by the combination dials, biasing means urging the locking member to a locking position and coupling means between the manual actuator and the locking member, the manual actuator being movable from a first position to a second position for moving the locking member from its locking position and for releasing the coupling means, thereby allowing the biasing means to return the locking member to its locking position, and the manual actuator then being movable beyond said second position to operate said drive means, return of the actuator to the first position reengaging the coupling means.

A combination lock comprising a casing having a faceplate, a plurality of indicia-bearing combination dials supported for coaxial rotation on a shaft in said casing, said dials having peripheral portions exposed through corresponding openings in said faceplate for manual rotation of the dials individually, dial spring means in said casing for engaging said dials to index the same as they are rotated, a manual actuator supported in said casing for movement between a locked position and an unlocked position, said actuator having a portion exposed through a corresponding opening in said faceplate for manual movement of said actuator, locking means in said casing controlled by said dials and coupled to said manual actuator for permitting said manual actuator to move from said locked position to said unlocked position only when the dials are disposed in particular orientations so as to display at their said peripheral portions a predetermined combination of said indicia for opening the lock, said locking means comprising a locking member supported for movement in said casing in a predetermined direction in response to movement of said manual actuator toward its unlocked position, said manual actuator being coupled to said locking member by releasable coupling means that uncouple said manual actuator from said locking member in response to a predetermined amount of movement of said manual actuator toward its unlocked position, means connecting said manual actuator to said dial spring means for disengaging the dial spring means from the dials when the manual actuator is moved toward said unlocked position, and means responsive to movement of said manual actuator toward said unlocked position for rotating all of said dials to predetermined orientations at which said peripheral portions of the dials display a predetermined combination of indicia different from the combination of indicia for opening the lock, said locking member having means for biasing the same in a direction opposite to said predetermined direction, whereby said locking member moves with said manual actuator toward its unlocked position and, when uncoupled from said manual actuator, moves in the opposite direction.

A combination lock comprising a casing having a faceplate, a plurality of indicia-bearing combination dials supported for side-by-side coaxial rotation on a shaft in said casing, said dials having peripheral portions exposed through corresponding openings in said faceplate for manual rotation of the dials individually, dial spring means in said casing for engaging said dials to index the same as they are rotated, a manual actuator supported in said casing for movement along the length of said shaft between a locked position and an unlocked position, said actuator having a portion exposed through a corresponding opening in said faceplate adjacent to a terminal one of said dials for manual movement of said actuator, locking means in said casing controlled by said dials and coupled to said manual actuator for permitting said manual actuator to move from said locked position to said unlocked position only when the dials are disposed in particular orientations so as to display at their said peripheral portions a predetermined combination of said indicia for opening the lock, means connecting said manual actuator to said dial spring means for disengaging the dial spring means from the dials when the manual actuator is moved toward said unlocked position, and means responsive to movement of said manual actuator toward said unlocked position for rotating all of said dials to predetermined orientations at which said peripheral portions of the dials display a predetermined combination of indicia different from the combination of indicia for opening the lock.