This article needs additional citations for verification .(January 2017) |
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.
Ancient remains of stone, marble, wood, and bronze hinges have been found. Some date back to at least Ancient Egypt, although it is nearly impossible pinpoint exactly where and when the first hinges were used. [1]
In Ancient Rome, hinges were called cardō and gave name to the goddess Cardea and the main street Cardo. This name cardō lives on figuratively today as "the chief thing (on which something turns or depends)" in words such as cardinal . [2]
According to the OED, the English word hinge is related to hang .
Other types of hinges include:
Since at least medieval times, there have been hinges to draw bridges for defensive purposes for fortified buildings. Hinges are used in contemporary architecture where building settlement can be expected over the life of the building. For example, the Dakin Building in Brisbane, California, was designed with its entrance ramp on a large hinge to allow settlement of the building built on piles over bay mud. This device was effective until October 2006, when it was replaced due to damage and excessive ramp slope.
Hinges appear in large structures such as elevated freeway and railroad viaducts, to reduce or eliminate the transfer of bending stresses between structural components, typically in an effort to reduce sensitivity to earthquakes. The primary reason for using a hinge, rather than a simpler device such as a slide, is to prevent the separation of adjacent components. When no bending stresses are transmitted across the hinge, it is called a zero moment hinge.
A variety of self-actuating, self-locking hinges have been developed for spacecraft deployable structures such as solar array panels, synthetic aperture radar antennas, booms, radiators, etc. [6]
A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fits into the doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.
A mortiseand tenon joint connects two pieces of wood or other material. Woodworkers around the world have used it for thousands of years to join pieces of wood, mainly when the adjoining pieces connect at right angles.
A leaf spring is a simple form of spring commonly used for suspension in wheeled vehicles. Originally called a laminated or carriage spring, and sometimes referred to as a semi-elliptical spring, elliptical spring, or cart spring, it is one of the oldest forms of vehicle suspension. A leaf spring is one or more narrow, arc-shaped, thin plates that are attached to the axle and chassis in a way that allows the leaf spring to flex vertically in response to irregularities in the road surface. Lateral leaf springs are the most commonly used arrangement, running the length of the vehicle and mounted perpendicular to the wheel axle, but numerous examples of transverse leaf springs exist as well.
A balisong, also known as a butterfly knife, fan knife or Batangas knife, is a type of folding pocketknife that originated in the Philippines. Its distinct features are two handles counter-rotating around the tang such that, when closed, the blade is concealed within grooves in the handles. A latch sometimes holds the handles together; typically mounted on the one facing the cutting edge. An exceptionally large balisong is called a balisword.
A double wishbone suspension is an independent suspension design for automobiles using two wishbone-shaped arms to locate the wheel. Each wishbone or arm has two mounting points to the chassis and one joint at the knuckle. The shock absorber and coil spring mount to the wishbones to control vertical movement. Double wishbone designs allow the engineer to carefully control the motion of the wheel throughout suspension travel, controlling such parameters as camber angle, caster angle, toe pattern, roll center height, scrub radius, scuff, and more.
Door furniture or door hardware refers to any of the items that are attached to a door or a drawer to enhance its functionality or appearance.
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.
A door closer is a mechanical device that regulates the speed and action of a door’s swing. Manual closers store the force used to open the door in some type of spring and reuse it to close the door. Automatic types use electricity to regulate door swing behavior.
The lock of a firearm is the mechanism used to initiate firing. It is generally used as a historical term, referring to such mechanisms used in muzzle-loading and early breech-loading firearms, as modern firearms uniformly fire by use of a firing pin to strike the rear of a cartridge. 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.
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.
In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles, and are used on virtually every automobile made. They bionically resemble the ball-and-socket joints found in most tetrapod animals.
The neck is the part of certain string instruments that projects from the main body and is the base of the fingerboard, where the fingers are placed to stop the strings at different pitches. Guitars, banjos, ukuleles, lutes, the violin family, and the mandolin family are examples of instruments which have necks. Necks are also an integral part of certain woodwind instruments, such as the saxophone.
The piano action mechanism of a piano or other musical keyboard is the mechanical assembly which translates the depression of the keys into rapid motion of a hammer, which creates sound by striking the strings. Action can refer to that of a piano or other musical keyboards, including the electronic or digital stage piano and synthesizer, on which some models have "weighted keys", which simulate the touch and feel of an acoustic piano. The design of the key action mechanism determines the "weight" of the keys, i.e., the force required to sound a note; that is, the feeling of the heaviness of the touch of the keys. "A professional pianist is likely to care most about the piano's action, because that is what controls its responsiveness and relative lightness--or heaviness--of touch. Roughly speaking, a piano's action is light when its keys fall easily under the fingers, and heavy when a noticeable downward thrust is required. The action, in short, is what makes a piano playable or not to an individual musician."
An electric strike is an access control device used for door frames. It replaces the fixed strike faceplate often used with a latch. Like a fixed strike plate, it normally presents a ramped or beveled surface to the locking latch allowing the door to close and latch just like a fixed strike would. However, an electric strike's ramped surface can, upon command, pivot out of the way when the lock on the door is in the locked position and the door is opened, allowing a user to pull/push the door to open it without operating the mechanical lock or using a mechanical key. After the door is opened past the keeper, the keeper returns to its standard position and re-locks when power is removed or applied, depending upon the strike's configuration.
Break action is a type of firearm action in which the barrel(s) are hinged much like a door and rotate perpendicularly to the bore axis to expose the breech and allow loading and unloading of cartridges. A separate operation may be required for the cocking of a hammer to fire the new round. There are many types of break-action firearms; break actions are universal in double-barreled shotguns, double-barreled rifles, combination guns, and are commonly found in single shot pistols, rifles, shotguns, including flare guns, grenade launchers, air guns, and some older revolver designs. They are also known as hinge-action, break-open, break-barrel, break-top, or, on old revolvers, top-break actions.
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.
This glossary of woodworking lists a number of specialized terms and concepts used in woodworking, carpentry, and related disciplines.
Window shutter hardware, usually made of iron, are hinges and latches that attach to the shutter and a window frame. The hinges hold the shutter to the structure and allow the shutter to open and close over the window. The latches secure the shutter in the closed position. Tie-back hardware can be used to hold the shutter in the open position.
A geared continuous hinge is a type of continuous hinge used mostly on doors in high-traffic entrances and features gear teeth that mesh together under a cap that runs the length of the hinge. The hinges use a number of fasteners to attach the door to the frame from top to bottom to distribute a door’s weight more evenly along the frame to stop doors from sagging. They are often used in schools, hospitals, hotels, offices, airports, stadiums, storefronts and many other commercial and industrial buildings.