Cylinder lock
A cylinder lock is a locking device in which a lock cylinder is used as a drive for the actual lock device .
concept
The cylinder lock is based on the concept of separating functions. The lock itself causes the actual locking (locking) of the door, while the function of the drive of the bolt or the latch as well as securing the locking mechanism against foreign keys (or other unauthorized opening attempts) is taken over by the lock cylinder .
Construction
In the building industry, cylinder locks are mostly manufactured as mortise locks that are pushed into a corresponding recess ( lock pocket) in the narrow side of a door leaf and fastened to the door with screws. Both the mortise lock and the door leaf must have a suitable opening on the side for inserting the lock cylinder. The lock cylinder is fixed with a long screw that is turned into the cylinder from the narrow side of the open door through the so-called faceplate of the mortise lock.
A driver protruding from the profile cylinder at the bottom drives the bolt of the lock. If the mortise lock has a so-called changeover , the catch of the lock can also be withdrawn via the driver. This is necessary, for example, for house entrances, staff entrances, etc. if they only have a door knob (instead of a handle) on the outside.
The driver of the cylinder can be compared to the key bit of a key for tumbler or chubbing locks , which usually drives the bolt directly in box or mortise locks for simple room doors. The internal structure of a cylinder lock otherwise corresponds to these conventional locks. The main difference is that a smaller key is used in the cylinder lock, which first acts on the driver of the lock cylinder instead of directly activating the bolt.
The driver of the lock cylinder is normally arranged in such a way that it protrudes laterally obliquely out of the cylinder in the state in which the key can be removed from the cylinder. In this way, the cylinder is locked inside the mortise lock so that it cannot be removed or changed without a suitable key.
The latch of the cylinder lock can in principle also be operated without a profile cylinder via the door handle ( handle ), so that the door can also be used without a lock cylinder. The openings provided for the cylinder can be covered by door rosettes or blanking plates. The lock cylinder is only required to lock the lock.
If the cylinder locks have not yet been equipped with a door handle (handle) and cylinder during the construction phase in new buildings, the handle follower can be operated with a so-called construction key to retract the latch and open the door.
advantages
Advantages of cylinder locks compared to conventional tumbler or chubb locks:
- Cylinders of various degrees of security can be used, from simple security cylinders to those with electronic security elements or armor.
- If the locking needs change, it is easier to swap out the cylinder than to change the entire lock. Theoretically, the individual cylinders can be adapted to other keys by exchanging the standardized locking pins.
history
Linus Yale Junior, son of an American locksmith , is responsible for the cylinder lock as we know it today . In 1850 he got into the lock business of his father Linus Yale Senior in Franklin County (Massachusetts) and expanded the Pin Tumbler Lock (to German security lock ) developed by Yale Senior . In doing so, he took up the old principle of the Egyptian drop bolt lock and developed the first security cylinder lock using special pin tumblers in the years 1860–65. Until 1865, keys had to be long enough to reach through the door as most door locks were on the inside of the door. By using four pairs of locking pins and installing them in a cylinder (a novelty at the time), the shape and length of the key could be reduced to a uniform, much shorter dimension, regardless of the thickness of the door in which the cylinder was installed. The locking pins prevented opening with another, similarly constructed key, as the length of the respective locking pins was precisely adapted to the differences in level of the key bit compatible with the lock . So there was only one key that could actually open the lock. With this invention, the foundation for all subsequent cylinder lock variants was laid. The work of the two Yales - especially the latter - had a deep and lasting impact on the lock industry. Almost all American and many foreign lock manufacturers have adopted the principles of Yale's lock construction and have followed their example in design and production methods.