- Project plans
- Project activities
- Legislation and standards
- Industry context
- Specialist wikis
Last edited 11 Mar 2021
How door locks work
|This iron metalwork object is a 16th century rim lock and key from France.|
A door lock is a mechanism used for security purposes - preventing a door from being opened by unauthorised people. There are many different types of door locks. Two of the most basic types of locks are rim locks and cylinder locks.
One of the oldest types of locks, the rim lock uses a bolt and key to secure the door. The bolt in the lock is moved when the correct key is inserted into the mechanism and turned. This action presses the tumbler - which is kept in place by a spring - up, and frees the bolt.
A cylinder lock uses a rotating mounted plug. When locked, the cylinder is held in place by several pin tumblers that have been moved into the proper position by springs. This allows the pins to fit into corresponding holes in the cylinder and keep the cylinder from moving.
A key is then inserted into the lock, which raises the pins so their tops move to a position that corresponds to the top of the outer surface of the cylinder. When the different segments of the tumbler are not connected, the cylinder can move freely when the key is turned. This allows the bolt to move and unlocks the door.
 Related articles on Designing Buildings Wiki
Featured articles and news
It’s not always a case of the centre leading.
PHribbon toolbar developed for US market.
CIOB consultation seeks feedback on APPG 2020 report.
How to respond to changes made in the October 2021 update.
Resource provides professional installation assistance.
Adaptive planning proposal spans 15 years.
Activities summarised by the Construction Industry Council.
How Islamic architecture shaped Europe. Book review.
The campaign to preserve a rare blacksmith bridge.