A knife is a tool or weapon with a cutting edge or blade, usually attached to a handle or hilt. One of the earliest tools used by humanity, knives appeared at least 2.5 million years ago, as evidenced by the Oldowan tools. Originally made of wood, bone, and stone, over the centuries, in step with improvements in both metallurgy and manufacturing, knife blades have been made from copper, bronze, iron, steel, ceramic, and titanium. Most modern knives have either fixed or folding blades; blade patterns and styles vary by maker and country of origin.
A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is 19 inches (482.6 mm) wide. The 19 inch dimension includes the edges or ears that protrude from each side of the equipment, allowing the module to be fastened to the rack frame with screws or bolts. Common uses include computer servers, telecommunications equipment and networking hardware, audiovisual production gear, music production equipment, and scientific equipment.
A hinge is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation, with all other translations or rotations prevented; thus a hinge has one degree of freedom. Hinges may be made of flexible material or moving components. In biology, many joints function as hinges, such as the elbow joint.
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 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 child safety lock is a special-purpose lock for cabinets, drawers, bottles, etc. that is designed to help prevent children from getting at any dangerous things or contents. Young children are naturally curious about their surroundings and will always explore, but as they may be unaware of dangerous substances or situations, the results can be fatal. Numerous cases of poisoning have resulted from eating brightly colored pills or spilling cleaning solvents.
A bank vault is a secure space where money, valuables, records, and documents are stored. It is intended to protect their contents from theft, unauthorized use, fire, natural disasters, and other threats, much like a safe. Unlike safes, vaults are an integral part of the building within which they are built, using armored walls and a tightly fashioned door closed with a complex lock.
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.
Crimping is a method of joining two or more pieces of metal or other ductile material by deforming one or both of them to hold the other. The bend or deformity is called the crimp. Crimping tools are used to create crimps.
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 butt joint is a wood joint in which the end of a piece of material is simply placed against another piece. The butt joint is the simplest joint. An unreinforced butt joint is also the weakest joint, as it provides a limited surface area for gluing and lacks any mechanical interlocking to resist external forces.
A leglock is a joint lock that is directed at joints of the leg such as the ankle, knee or hip joint. A leglock which is directed at joints in the foot is sometimes referred to as a foot lock and a lock at the hip as a hip lock. Leglocks are featured, with various levels of restrictions, in combat sports and martial arts such as Sambo, Brazilian Jiu-Jitsu, catch wrestling, mixed martial arts, Shootwrestling and submission wrestling, but are banned in some sports featuring joint locks such as judo. The technique has been seen across a wide range of different combat sports and is reportedly over 2,500 years old, having been seen in the lost art of Pankration in the original Olympic Games.
A grappling hold, commonly referred to simply as a hold that in Japanese is referred to as katame-waza, is any specific grappling, wrestling, judo, or other martial art grip that is applied to an opponent. Grappling holds are used principally to control the opponent and to advance in points or positioning. The holds may be categorized by their function, such as clinching, pinning, or submission, while others can be classified by their anatomical effect: chokehold, headlock, joint-lock, or compression lock. Multiple categories may be appropriate for some of these holds.
A bayonet mount or bayonet connector is a fastening mechanism consisting of a cylindrical male side with one or more radial pins, and a female receptor with matching L-shaped slot(s) and with spring(s) to keep the two parts locked together. The slots are shaped like a capital letter L with serif ; the pin slides into the vertical arm of the L, rotates across the horizontal arm, then is pushed slightly upwards into the short vertical "serif" by the spring; the connector is no longer free to rotate unless pushed down against the spring until the pin is out of the "serif".
A keycard lock is a lock operated by a keycard, a flat, rectangular plastic card. The card typically, but not always, has identical dimensions to that of a credit card or American and EU driver's license. The card stores a physical or digital pattern that the door mechanism accepts before disengaging the lock.
The Model 1200 is a pump-action shotgun that was manufactured by the Winchester-Western Division of Olin Corporation, starting 1964. It was redesignated the Model 1300 in 1978 with minimal changes. Production ceased in 2006 when the U.S. Repeating Arms Company, the subsequent manufacturer, went bankrupt. A militarized version of the Model 1200 was acquired by the U.S. Army for use during the Vietnam War. It is still in active service within various conflicts throughout the 21st century.
Butt welding is when two pieces of metal are placed end-to-end without overlap and then welded along the joint. Importantly, in a butt joint, the surfaces of the workpieces being joined are on the same plane and the weld metal remains within the planes of the surfaces.
A locker is a small, usually narrow storage compartment. They are commonly found in dedicated cabinets, very often in large numbers, in various public places such as locker rooms, workplaces, schools, transport hubs and the like. They vary in size, purpose, construction, and security.
Three-point locking, or a multipoint lock, is a locking system installed in cabinet or locker doors to enable more secure locking. Whereas in single-point locking, the door on a cabinet locks only at the point where the key is turned, halfway up the edge of the door, three-point locking enables the top and bottom of the door to be simultaneously secured. This is accomplished by attaching two long steel rods to the lock on the inside of the door, which extend vertically upwards and downwards: when the lock is turned, the rotary movement of the latch on the inside of the door translates to vertical movement in these rods, with the result that the upper rod moves upwards by an inch or so, and the lower rod moves downwards similarly. This causes the ends of the rods to move through small holes in the flanges at the top and bottom of the door, resulting from the metal of the door being turned inwards, and the rods then move a short distance into holes in the metal surrounding the door. This effectively immobilizes the top and bottom of the door, and greatly increases the security of the door-locking compared to a door with only single-point locking.
A twistlock or twist lock, together with matching corner castings, as defined in norms including ISO 1161:1984, form a standardized (rotating) connector system, for connecting and securing intermodal, and predominantly ISO-standard international shipping containers. The primary uses are to securely stack containers, for locking them into place on a container ship, semi-trailer or rail carriage, and for lifting and handling by specific container-handling equipment, like straddle carriers, reach stackers, container-handling forklifts, sidelifters, and various types of container cranes.
