A warded lock (also called a ward lock) is a type of lock that uses a set of obstructions, or wards, to prevent the lock from opening unless the correct key is inserted. The correct key has notches or slots corresponding to the obstructions in the lock, allowing it to rotate freely inside the lock.
The warded lock is one of the oldest lock designs, found as far back as ancient China and Rome. [1] During the Middle Ages they were used prolifically on monasteries where, because money and time were available, their complexity grew. Warded locks are still in use today in the UK and Ireland for low-security applications, and on heritage sites such as ancient monuments and churches to preserve original features, with primary security being provided by other means such as a lever lock mechanism installed in addition. [2]
In a basic warded lock, a set of obstructions, often consisting of concentric plates protruding outwards, blocks the rotation of a key not designed for that lock. Warded locks may have one simple ward, or many intricate wards with bends and complex protrusions; the principle remains the same. Unless the notches or slots in the key correspond to the wards in the lock, the key will strike an obstruction and will not turn. [3]
Additionally, a series of grooves on either side of the key's blade may limit the type of lock the key can slide into. As the key slides into the lock through the keyway, the wards align with the grooves in the key's profile to allow or deny entry into the lock cylinder. [3] Although this is not commonly recognized when discussing warded locks, it is more applicable to current locksmithing applications such as pin-tumbler or wafer-tumbler locks.
In double-sided locksets (meaning locksets where the key can be inserted from either side of the door) the centre of the key shaft is solid and protrudes past the end of the bit, which slots into a hole on the opposite side of the lock. Double-sided ward locks nearly always have perfectly symmetrical bits. For single-sided locks, a cylindrical post is typically located in the center of the lock. Its purpose is to provide a point of leverage and pivot for rotating the key, and to help correctly align the key with the wards. The key has a corresponding hole which fits over the post.
When the correct key is inserted, it will clear the wards and rotate about the center post. The key may then strike a lever, activating a latch or sliding bolt, or it may itself push against the latch or bolt. In a double acting lever lock, the key may additionally push against a spring-loaded lever which holds the sliding bolt in place.
Due to the design of the lock, a well designed skeleton key can be made to bypass the wards. For this reason, warded lock mechanisms are generally used in low-security applications. There are also a very limited number of unique keys that can be created, so many keys will be able to open other doors that they were not designed to open. [3]
The invention of the lever tumbler lock solves this problem, as each lever is required to be lifted to a certain height in order to operate the locking mechanism.
Lock picking is the practice of unlocking a lock by manipulating the components of the lock device without the original key.
The pin tumbler lock, also known as the Yale lock after the inventor of the modern version, is a lock mechanism that uses pins of varying lengths to prevent the lock from opening without the correct key.
A disc tumbler or disc detainer lock is a lock composed of slotted rotating detainer discs. The lock was invented by Finnish founder of Abloy, Emil Henriksson (1886–1959) in 1907 and first manufactured under the Abloy brand in 1918.
A combination lock is a type of locking device in which a sequence of symbols, usually numbers, is used to open the lock. The sequence may be entered using a single rotating dial which interacts with several discs or cams, by using a set of several rotating discs with inscribed symbols which directly interact with the locking mechanism, or through an electronic or mechanical keypad. Types range from inexpensive three-digit luggage locks to high-security safes. Unlike ordinary padlocks, combination locks do not use keys.
A lock is a mechanical or electronic fastening device that is released by a physical object, by supplying secret information, by a combination thereof, or it may only be able to be opened from one side, such as a door chain.
A lever tumbler lock is a type of lock that uses a set of levers to prevent the bolt from moving in the lock. In the simplest form of these, lifting the tumbler above a certain height will allow the bolt to slide past.
A mortise lock is a lock that requires a pocket—the mortise—to be cut into the edge of the door or piece of furniture into which the lock is to be fitted. In most parts of the world, mortise locks are found on older buildings constructed before the advent of bored cylindrical locks, but they have recently become more common in commercial and upmarket residential construction in the United States. The design is widely used in domestic properties of all vintages in Europe.
A door handle or doorknob is a handle used to open or close a door. Door handles can be found on all types of doors including exterior doors of residential and commercial buildings, internal doors, cupboard doors and vehicle doors. There are many designs of door handle, depending on the appropriate use. A large number of handles, particularly for commercial and residential doors, incorporate latching or locking mechanisms or are manufactured to fit to standardised door locking or latching mechanisms.
A breechblock is the part of the firearm action that closes the breech of a breech loading weapon before or at the moment of firing. It seals the breech and contains the pressure generated by the ignited propellant. Retracting the breechblock allows the chamber to be loaded with a cartridge.
The lock of a firearm is the mechanism used to initiate firing. It is a historical term, in that it generally refers to such mechanisms used in muzzle-loading and early breech-loading firearms. Side-lock refers to the type of construction, in which the individual components of the mechanism are mounted either side of a single plate. The assembly is then mounted to the stock on the side of the firearm. In modern firearm designs, the mechanism to initiate firing is generally constructed within the frame or receiver of the firearm and is referred to as the firing or trigger mechanism.
Padlocks are portable locks usually with a shackle that may be passed through an opening to prevent use, theft, vandalism or harm.
Bitting is the depth of key cuts on a cylinder key for a pin tumbler lock, often expressed as a number. Bitting also refers to the combination of key cuts on a bit key for a warded lock or lever tumbler lock.
A latch or catch is a type of mechanical fastener that joins two objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the other mounting surface. Depending upon the type and design of the latch, this engaged bit of hardware may be known as a keeper or strike.
A skeleton key is a type of master key in which the serrated edge has been removed in such a way that it can open numerous locks, most commonly the warded lock. The term derives from the fact that the key has been reduced to its essential parts.
Lock bumping is a lock picking technique for opening a pin tumbler lock using a specially crafted bump key, rapping key or 999 key. A bump key must correspond to the target lock in order to function correctly.
A wafer tumbler lock is a type of lock that uses a set of flat wafers to prevent the lock from opening unless the correct key is inserted. This type of lock is similar to the pin tumbler lock and works on a similar principle. However, unlike the pin tumbler lock, where each pin consists of two or more pieces, each wafer in the lock is a single piece. The wafer tumbler lock is often incorrectly referred to as a disc tumbler lock, which uses an entirely different mechanism.
The term protector lock has referred to two unrelated lock designs, one invented in the 1850s by Alfred Hobbs, the other in 1874 by Theodor Kromer.
A magnetic keyed lock or magnetic-coded lock is a locking mechanism whereby the key utilizes magnets as part of the locking and unlocking mechanism. Magnetic-coded locks encompass knob locks, cylinder locks, lever locks, and deadbolt locks as well as applications in other security devices.
A lockset is the hardware and components that make up the locking or latching mechanism that can usually be found on a door or other hinged object but can also include sliding doors and dividers. The components of a lockset can include the door handles, latch bolt, dead bolt, face plate, strike plate, escutcheon, thumbturn, push button, turn button, and other trim. The lockset and associated hardware typically defines a door's function and how a user could access the two adjacent spaces defined by the opening associated with the lockset.
This is a glossary of locksmithing terms.
| Fundamental concepts |  | |
|---|---|---|
| Components and hardware | ||
| Keys | ||
| Mechanical locks | ||
| Electronic locks | ||
| Other lock types | ||
| Lock picking | ||
| Security alarms |
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| Miscellaneous | ||
