For the 1957 film, see Time Lock

Time Lock

Time Lock is a 1957 British thriller film directed by Gerald Thomas. The plot is about a six-year old boy who is accidentally locked in a bank vault. With less than 10 hours of oxygen left in the vault, it becomes a race to save the boy. The film features a young, pre-James Bond Sean Connery...

A time lock (also timelock) is a part of a locking mechanism commonly found in bank vault

Bank vault

A bank vault is a secure space where money, valuables, records, and documents can be stored. It is intended to protect their contents from theft, unauthorized use, fire, natural disasters, and other threats, just like a safe...

s and other high-security containers. The timelock is a timer designed to prevent the opening of the safe or vault until it reaches 0, even if the correct combination(s) are known. Most safes or vaults utilize at least two independent clock mechanisms as a fail-safe system to guarantee the unlocking of the safe in case one of the timers (called movements) fails. Only one needs to reach 0 in order for the safe to be opened. Timelocks can typically be set from 15 minutes to 144 hours (6 days).

Timelocks are mounted on the inside of the safe's or vault's door; they are not visible when the door is closed and locked.

Timelocks were originally created to prevent criminals from kidnapping and torturing the person(s) who knows the combination, and then using the extracted information to later burgle the safe or vault.

Timelocks are not to be confused with time-delay combination locks

Time-delay combination locks

A time-delay combination lock is most commonly a digital electronic combination lock equipped with a delay timer that delays the unlocking of the lock by a user definable delay period, usually less than one hour...

, which will open at any time with the correct combination, but will not actually unlock until a set delay period elapses, usually less than one hour.

Modern timelocks are electronic but otherwise serve the same function as the old mechanical, wind-up timelock. When the battery dies, the timelock unlocks.

Operation

Both mechanical and electronic timelocks are set by installing a winding key on the arbor (square post) near the bottom of the timelock and then turning it until the desired amount of time is set. Just before closing the safe or vault, the timelock is set to a certain number of hours and minutes. The timelock will count down to zero at some point before the vault will actually be unlocked the next day. At that point the timelock(s) will be at 0 and the vault can be unlocked and opened.

A properly adjusted mechanical timelock will keep running for up to 2 hours after reaching 0. Electronic timelocks turn off after they reach 0.