I.Mechanical key locksPrinciple and unlocking method
1、Code disc type lock
This is a high-reliability, all-mechanical cipher lock with a large key capacity and no electronic components. Its operation is unique, similar to the dial of an old telephone – starting from the initial position, rotate the dial clockwise to a specific digit, then return to the starting point, which enters one digit of the password. This process is repeated until all digits of the password are entered, and then the dial can be rotated counterclockwise to unlock. At the same time as unlocking, the internal mechanism is reset, so after returning the dial to the starting position to lock, the password must be re-entered to unlock. If the wrong password is entered, rotating the dial counterclockwise (simulated unlocking) can also reset the internal mechanism, and the password can be re-entered.
2、Multi-dial password lock
The simplest type of lock uses a common, low-security combination lock with multiple shims. Each shim has a recessed area in the middle. The central axis of the lock has several protruding teeth that are used to engage with the shims. When the shims are rotated to the correct combination, the lock can be opened. This type of lock is the easiest to open. Many such locks can be opened without knowing the combination. Unless the internal components are perfectly manufactured, simply pulling the axis outwards will cause one of the teeth to tighten against the shim. When the tightened shim is rotated until a small "click" sound is heard, it indicates that the tooth has entered the correct recess. Repeating this process allows the lock to be opened quickly.
II.Mechanical key locksAdvantages
1. Simple operation, similar to dialing a rotary phone. Single-axis operation: rotate clockwise half a turn to enter the password, and rotate counterclockwise half a turn to unlock. Short operating time.
2. The large number of passwords (over 3.25 million) and the fact that they are all permutations, allowing for unrestricted selection, pose a security risk.
3. The lock can be automatically destroyed without leaving any traces, and cannot be used for password cracking.
4、The number of digits in the password can be set freely, with both simplified and traditional Chinese characters allowed. The maximum password length is 6 digits.
5、Fully mechanical structure, does not require power, and can be used in various harsh environments.
6、Compact size, comparable to standard door locks.
7. Suitable for use in locking mechanisms of vaults, weapon cabinets, safes, and other critical areas.