Mortise lock

Key lock closed

A mortise lock (also known as a keyhole lock or goblin) is a small locking cylinder that is primarily used to increase the security of tumbler locks. Small versions of the mortise lock can be used for furniture locks , special models also for trailer hitches and the like.

Tumbler locks offer insufficient security by today's standards, as they can be opened with the simplest of locking tools . Today they are used almost exclusively in room doors and are rarely found in house / apartment doors or public buildings. By using a mortise lock, the unauthorized opening of tumbler locks can be made more difficult. Furthermore, authorized persons (who have a key) can be temporarily denied operation. When installed, the mortise lock prevents the tumbler lock from being closed with the key provided.

For use, the mortise lock is inserted into the keyway of the tumbler lock and locked. It remains there and, like a stopper, prevents keys or locking tools from being inserted on both sides. Thus, the lock secured with the mortise lock can no longer simply be opened or closed.

The security of a lock with a profile cylinder is not achieved by key locks secured with mortise locks. This is primarily due to the large manufacturing tolerances of the mortise locks, which facilitate subsequent locking. In addition, mortise locks can be removed easily by force or the blockage of the locking channel can be bypassed with the help of a particularly thin locking tool.

technology

In the open state, the locking lug (rear part) is aligned with the body (front part) of the cylinder and thus enables it to be inserted into the keyway of the tumbler lock. After the key lock has been inserted, the key is turned. The locking lug rotates against the body of the mortise lock and engages in the case of the tumbler lock. Since the lock body cannot be rotated in the locking channel, the folded-out locking lug effectively prevents removal in the locked state.

The key, which is usually quite long, serves as an assembly aid during installation, as the mortise lock is protected inside the locking channel when it is installed; it can only be removed when it is closed.

Mortise locks are usually made of brass .