Blogging Prince : We Blog Whatever You Want: Types of Lock

A lock is a mechanical or electronic fastening device that is released by a physical object (such as a key, keycard, fingerprint, RFID card, or security token) or secret information (such as a keycode or password), or combination of more than one of these.

Typically, in pin-tumbler and wafer-tumbler applications, a lock in the rest position is closed. The key has a series of grooves on either side of the key (the key's blade), which limit the type of lock the key can slide into. As the key slides into the lock, the grooves on the blade of the key align with the wards in the keyway allowing or denying entry to the cylinder. Then, a series of pointed teeth and notches on the blade called bittings allow pins or wafers to move up and down until they are in line with the shear line of the inner and outer cylinder, allowing the cylinder or cam to rotate freely inside the lock and the lock to open.

Types of locks

Locks may be entirely mechanical, or electromechanical. They may be operated by turning some form of removable key, by keying or dialling in a combination which directly or via electromechanical means operates the lock, with some form of magnetic or other card reader, or by moving a part on a safety lock intended to prevent accidental operation rather than to prevent unauthorized access.

Warded lock

The warded lock is one of the earliest types of locks. It said to have been developed in China.

Tumbler locks

Pin-tumbler lock

The Pin tumbler lock is the most widespread lock in the western world. Pin-tumbler locks have been around in some form since 2000 BCE. The Egyptian form of this lock was large, heavy, and made of wood, with pins made of metal, usually bronze, but sometimes iron. This design in its modern form was first patented in 1805 in England. The patent holder was an American named A.O. Stansbury. In the middle of the 18th century, the American locksmiths Linus Yale Sr. and his son, Linus Yale Jr., refined the lock design into the form recognizable today. These early versions of the pin-tumbler lock were expensive to produce, and did not become widely available until mass production became feasible.

Wafer-tumbler lock

The first patent for the wafer lock was issued in the United States in 1868 to P.S. Felter. The wafer lock is relatively inexpensive to produce and is often used in automobiles and cabinetry. This type of lock is generally made of die-cast zinc alloy.

Lever locks

Lever locks were invented in Europe in the 17th century. This is a popular lock type for safes and North American prisons today, as they are generally built of strong materials. They are also used as door locks in some countries. This is the type of lock that replaced the medieval warded lock in the 19th century. Robert Barron of England patented the double-acting lever in 1778. Jeremiah Chubb would follow with his own detector lock in 1818.

Disc tumbler lock

The disc tumbler lock or Abloy lock was invented in 1907, and is widespread in Finland. The mechanism contains no springs and is durable. Picking the lock is too hard compared to alternative means of gaining entry.

Other types

There are also many other types of lock, such as warded locks, tubular locks, electronic locks (itself a huge area) and also many variations of the various types, such as dimple locks, which are a variation on Yale's original cylinder lock in which the pins interact with the side of the key rather than the edge, "laser track" car locks, which are a variation on wafer locks, and some higher security lever locks also include the types of warding found on warded locks.

List of common locks