A plug assembly including a plug, a sidebar movably mounted on the plug, and a plurality of rack pins seated in the plug. The sidebar is biased to an outer position in which the sidebar extends beyond an outer surface of the plug. Each rack pin includes a key-following leg and a sidebar-engaging leg. The sidebar-engaging leg includes at least one true gate. When a true gate of each rack pin is aligned with the sidebar, the sidebar is free to move radially inward to an inner position.

A key-operated lock comprising a housing, a core and a set of pin stacks. The housing has a set of driver chambers and a set of inactive master-pin chambers. Each pin stack comprises pin stack elements, which include a driver and a tumbler. The driver is movably mounted in one of the driver chambers. The tumbler assembly is movably mounted in the core for radial movement relative to the bore in the body. Further, the tumbler assemblies including a plurality of releasably engaged parts movable relative to each other upon disengagement to change a dimension of the tumbler assemblies. Additionally, for at least one of the pin stacks, the pin stack elements further comprise one or more master pins.

A rekeyable lock cylinder with a cylinder body and a plug assembly. The lock cylinder includes a plurality of key followers and a corresponding plurality of racks disposed in the plug assembly. Disengaging the racks from the key followers allows rekeying of the lock cylinder.

A rekeyable lock cylinder with a cylinder body and a plug assembly. The lock cylinder includes a plurality of key followers and a corresponding plurality of racks disposed in the plug assembly. Disengaging the racks from the key followers allows rekeying of the lock cylinder.

An exemplary lock apparatus includes a housing and a plug assembly rotatably mounted in the housing. The plug assembly includes a tumbler assembly operable to selectively prevent rotation of the plug assembly relative to the housing and a retention mechanism operable to selectively prevent removal of the plug assembly from the housing. A system including the lock apparatus may include a change key configured to actuate the tumbler assembly without actuating the retention mechanism and/or a control key configured to actuate both the tumbler assembly and the retention mechanism.

A system including a lock class having a plurality of lock families, with each lock family including a plurality of lock cylinders. Each of the lock families has a control pin location which is different from the control pin location of another of the lock families within the lock class. Each of the lock cylinders generally includes a shell, a plug rotatably mounted in the shell, and a control ring rotatably mounted on the plug at the control pin location of the lock family of which the lock cylinder is a member, and a control pin operable to selectively couple the plug with the control ring. Each lock family may be associated with a control key family. Each control key family may include a plurality of control keys, each of which may have a control bitting configured to urge control pins of the associated lock family to a coupling position.

In one aspect of the present disclosure, a locking device is provided including an interchangeable core (IC), a barrel, an anti-rotation plate, a prong driver, a bolt and a backplate. The barrel is coupled to the backplate and includes a hollow interior to receive the IC. The bolt is slidably disposed in a slot of the backplate. The IC includes a key hole. The prong driver is coupled to the IC and the bolt, such that, when a proper key is inserted into the key hole and rotated the bolt can be extended from the slot in a direction away from the locking device or retracted into the slot in a direction toward the interior of the locking device. The anti-rotation plate of the locking device is coupled to the barrel to prevent the locking device from being rotated relative to a structure the locking device is mounted to.

In one aspect of the present disclosure, a locking device is provided including an interchangeable core (IC), a barrel, an anti-rotation plate, a prong driver, a bolt and a backplate. The barrel is coupled to the backplate and includes a hollow interior to receive the IC. The bolt is slidably disposed in a slot of the backplate. The IC includes a key hole. The prong driver is coupled to the IC and the bolt, such that, when a proper key is inserted into the key hole and rotated the bolt can be extended from the slot in a direction away from the locking device or retracted into the slot in a direction toward the interior of the locking device. The anti-rotation plate of the locking device is coupled to the barrel to prevent the locking device from being rotated relative to a structure the locking device is mounted to.

Lock assemblies having cylinders with interchangeable cores are provided. In one embodiment a lock assembly comprises a cylinder including a keyway and a core. Also, the lock assembly includes a first driver operatively connected to the cylinder. In particular, key cuts of the core are changeable without removing the cylinder from the driver.

A self-learning lock cylinder assembly or lock tumbler and tools capable of teaching the self-learning key configuration of a pre-existing key is disclosed. The individual performing the self-learning does not need to have prior locksmith experience. The individual performing the self-learning procedure can verify that the original key and copies of the original key function properly within the lock cylinder prior to final assembly and installation in the lock through a self-learning test housing. The pre-installation testing eliminates problems associated with an incorrectly assembled lock cylinder