timedlock

A timed lock is a locking device that remains in a locked state until a predetermined time or countdown has elapsed. It is designed to enforce access windows and reduce the risk of unauthorized or opportunistic entry. Timed locks are commonly used on safes, vaults, and other high-security containers.

There are two main forms: mechanical and electronic. Mechanical time locks use a clockwork timer that drives a lever or cam to release the lock at a preset moment. They are often installed behind a standard vault lock and require a separate combination or key to operate once the timer allows. In two-person control systems, one person holds the physical key while the other must wait for the timer to permit access. Electronic time locks rely on an internal real-time clock and programmable software. Access windows can be scheduled, one-time or recurring, and unlock can require authentication. Electronic locks typically provide audit logs, status indicators, and integration with alarms, and run on batteries or a power supply.

History and use: Mechanical time locks gained prominence in the early 20th century as a security enhancement for bank vaults; manufacturers such as Sargent & Greenleaf produced widely used models. Today, both mechanical and electronic variants are used in banks, casinos, data centers, and other facilities requiring controlled release of valuables or sensitive assets.

Limitations and risks: Mechanical time locks can fail or be mis-set, and electronic units can suffer power outages, software glitches, or tampering. Proper maintenance, periodic testing, dual-control procedures, secure programming, and alarms are important to maintaining reliability and security.

See also: time-locked encryption and time-release cryptography.