Abstract: A lock assembly having a key plug with an axis, a first housing defining a receptacle for the key plug and guiding movement of the key plug in the receptacle around the key plug axis, a latch assembly including a first movable latch element, structure cooperating between the first housing and the latch assembly for supporting the latch assembly in an operative position on the first housing wherein the first latch element is movable between first and second positions relative to the first housing, a retaining element, structure for mounting the retaining element to the key plug for movement relative to the key plug between first and second positions, with the key plug being movable into the key plug receptacle to an operative position and removable from the key plug receptacle with the retaining element in its first position, and structure cooperating between the retaining element and latch assembly for preventing withdrawal of the key plug from the first housing receptacle with the key plug in its operative p

Abstract: A safety, insurance and alarm mechanical lock contains an external lock portion, a multicylinder type lock cylinder portion, and a lock body portion engaging with the lock cylinder portion. The lock cylinder portion comprises a front part including an external cylinder, a middle cylinder and an internal cylinder and a back part including a back external cylinder and a back internal cylinder. A self-locking control mechanism is provided between the front and back lock cylinders which can automatically perform self-locking and alarming when destroying act applied to the lock cylinder from outside takes place. The lock body portion is provided with an internal lock mechanism. Furthermore, in accordance with the various requirement, it can also be provided with an anti-invading mechanism, an alarm mechanism sensing the deformation of the door. The lock of the present invention has overcome many disadvantages of the prior lock and give a great deal of safety to users.

Abstract: A floating bar, ball bearing, dead bolt-type lock comprising rotatable plug means disposed within stationary core means and carrying a bolt rest means engagable with a reciprocal bolt member for selectively moving the bolt member between locked and unlocked positions. Floating bar means having cooperating elements disposed in both the plug means and core means retain ball bearing means in preselected positions for riding along one edge of the proper key in order to permit movement of the bolt member to an open position, and to permit movement of the bolt member to a closed position, and to substantially preclude picking of the lock.

Abstract: A lock assembly has a housing in which is provided a cylinder lock having a shell fixed in the housing and a plug rotatable in the shell by means of a key. A tongue is carried on and jointly rotatable with the plug and is formed with a plurality of bittings each engageable with a respective tumbler in the housing and displaceable into an aligned position. A locking element such as a bolt is engageable with the tumblers and is only displaceable between a locked and unlocked position when the tumblers are in the aligned position. The tongue is formed of a plurality of plates each constituting a respective one of the bittings. Thus even if the cylinder lock is forcibly ripped out of the assembly a tumbler-type lock structure is left within that cannot readily be overcome to allow operation of the locking element.