Design and operation of rotary combination locks
– Rotary combination locks have an internal mechanism consisting of wheels with notches called gates.
– The dial on the lock is connected to the internal mechanism and is used to release the shackle or lock bolt.
– The wheels are arranged in a stacked wheel pack and can be manipulated by turning the dial.
– The number of wheels determines the number of specific dial positions required to open the lock.
– As the dial rotates, the wheels are picked up and rotate together with the dial until all wheels are in position.
Wheel sandwich construction
– The wheels in a rotary combination lock are typically made of a three-layer sandwich.
– The outer layers, known as the wheel case, contain the gate and surround the wheel center.
– When a change key is inserted, it forces apart the lever arms, allowing the wheel center to rotate freely.
– This mechanism allows the owner to set a custom combination.
– The wheel center also includes the change key cam and lever arms.
Additional security features
– Some rotary combination locks include internal relockers that separately lock the shackle or bolt when an attack is detected.
– These relocking devices respond to attempts to dislodge or cut the locking mechanism.
– Other security measures include the use of radiotransparent materials for the wheels to prevent X-ray imaging.
– Tempered glass may be used to break in response to a drilling attempt.
– These additional security features enhance the resistance of the lock to various attacks.
Relationship to combination locks and safes
– Rotary combination locks are closely related to combination locks in general.
– Combination locks are commonly used in safes to provide security.
– Both types of locks rely on a specific sequence of numbers or positions to open.
– Safes are used to protect valuable items or documents.
– Understanding rotary combination locks can provide insights into the functioning of other types of locks.
References
– Sargent and Greenleaf Mechanical Safe Lock Guide provides detailed information on rotary combination locks.
– HowStuffWorks offers an explanation of how rotary combination locks work.
– A YouTube video demonstrates the functioning of a combination lock.
– Locraker is an automatic combination lock cracker designed to open rotary combination locks.
– The Safecracking for the computer scientist PDF provides insights into the techniques used in cracking combination locks.Sources: https://en.wikipedia.org/wiki/Rotary_combination_lock
