Rotary combination lock
Encyclopedia
A rotary combination lock is a lock
commonly used to secure safe
s and as an unkeyed padlock
mechanism. This type of locking mechanism consists of a single dial which must be rotated left and right in a certain combination in order to open the lock.
Contained inside the mechanism are discs, usually three, with notches that must be aligned to allow for a release of the piece holding the lock in place, and the lock to open. The position of the discs are manipulated by turning the dial left and right; on the dial is a catch - a sort of nub - and on each side of the discs is also a small catch. As the dial rotates, there will not be enough space for the catch on the dial to pass the catch on that side of the disc, and so the disc will begin to rotate with the dial. As this disc rotates, its catch will in turn begin rotating the next disc in a similar fashion. Once all discs and the dial are rotating together, the dial is rotated until the last disc is in place and the notch is in the proper positioning, then by rotating the dial in the other direction, the catches will all disconnect, starting from the dial to the first disc and so on until they connect from the other side and the discs begin to rotate together by the same method but in the opposite direction. In this way, the remaining discs are able to rotate and change their position without further disturbing the last disc. The process is completed back and forth until all discs are in place, and the lock is released.
Lock (device)
A lock is a mechanical or electronic fastening device that is released by a physical object or secret information , or combination of more than one of these....
commonly used to secure safe
Safe
A safe is a secure lockable box used for securing valuable objects against theft or damage. A safe is usually a hollow cuboid or cylinder, with one face removable or hinged to form a door. The body and door may be cast from metal or formed out of plastic through blow molding...
s and as an unkeyed padlock
Padlock
Padlocks are portable locks used to protect against theft, vandalism, sabotage, unauthorized use, and harm. They are designed to protect against some degree of forced and surreptitious entry.- History :...
mechanism. This type of locking mechanism consists of a single dial which must be rotated left and right in a certain combination in order to open the lock.
Contained inside the mechanism are discs, usually three, with notches that must be aligned to allow for a release of the piece holding the lock in place, and the lock to open. The position of the discs are manipulated by turning the dial left and right; on the dial is a catch - a sort of nub - and on each side of the discs is also a small catch. As the dial rotates, there will not be enough space for the catch on the dial to pass the catch on that side of the disc, and so the disc will begin to rotate with the dial. As this disc rotates, its catch will in turn begin rotating the next disc in a similar fashion. Once all discs and the dial are rotating together, the dial is rotated until the last disc is in place and the notch is in the proper positioning, then by rotating the dial in the other direction, the catches will all disconnect, starting from the dial to the first disc and so on until they connect from the other side and the discs begin to rotate together by the same method but in the opposite direction. In this way, the remaining discs are able to rotate and change their position without further disturbing the last disc. The process is completed back and forth until all discs are in place, and the lock is released.
External links
- How rotary combination locks work
- Rotary combination lock cracker
- Installing rotary combination locks
- Matt Blaze's paper Safecracking for Computer Scientists contains a detailed description, with photographs, of rotary combination locks and their security concerns