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Trunion
A trunnion () is a cylindrical protrusion used as a mounting or pivoting point. First associated with cannons, they are an important military development. In mechanical engineering (see the trunnion bearing section below), it is one part of a rotating joint where a shaft (the trunnion) is inserted into (and turns inside) a full or partial cylinder. Medieval history In a cannon, the trunnions are two projections cast just forward of the center of mass of the cannon and fixed to a two-wheeled movable gun carriage. With the creation of larger and more powerful siege guns in the early 15th century, a new way of mounting them became necessary. Stouter gun carriages were created with reinforced wheels, axles, and “trails” which extended behind the gun. Guns were now as long as in length and they were capable of shooting iron projectiles weighing from . When discharged, these wrought iron balls were comparable in range and accuracy with stone-firing bombards.Duffy, Chris ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mortar (weapon)
A mortar today is usually a simple, lightweight, man-portable, Muzzleloader, muzzle-loaded cannon, consisting of a Smoothbore, smooth-bore (although some models use a Rifling, rifled barrel) metal tube fixed to a base plate (to spread out the recoil) with a lightweight bipod mount and a Sight (device), sight. Mortars are typically used as indirect fire weapons for close fire support with a variety of ammunition. Historically mortars were heavy Siege, siege artillery. Mortars launch explosive shell (projectile), shells (technically called Bomb, bombs) in high arching Projectile motion, ballistic trajectories. History Mortars have been used for hundreds of years. The earliest reported use of mortars was in Korea in a 1413 naval battle when Korean gunsmiths developed the ''wan'gu'' (gourd-shaped mortar) (완구, 碗口). The earliest version of the ''wan'gu'' dates back to 1407. Ch'oe Hae-san (1380–1443), the son of Ch'oe Mu-sŏn (1325–1395), is generally credited with inventi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanisms (engineering)
Mechanism may refer to: *Mechanism (economics), a set of Game form, rules for a game designed to achieve Social choice function, a certain outcome **Mechanism design, the study of such mechanisms *Mechanism (engineering), rigid bodies connected by joints in order to accomplish a desired force and/or motion transmission *Mechanism (biology), explaining how a feature is created *Mechanism (philosophy), a theory that all natural phenomena can be explained by physical causes *Mechanism (sociology), a theory that all social phenomena can be explained by the existence of a deterministic mechanism Arts, films, and music * "The Mechanism", song by Disclosure * "Mechanism", song by Front Line Assembly from ''WarMech'' * The Mechanism (TV series), ''The Mechanism'' (TV series), a Netflix TV series See also *Machine *Machine (mechanical) *Linkage (mechanical) *Mechanism of action, the means by which a drug exerts its biological effects *Defence mechanism, unconscious mechanisms aimed a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardware (mechanical)
Hardware may refer to: Technology Computing and electronics * Electronic hardware, interconnected electronic components which perform analog or logic operations ** Digital electronics, electronics that operate on digital signals *** Computer hardware, physical parts of a computer *** Networking hardware, devices that enable use of a computer network ** Electronic component, device in an electronic system used to affect electrons, usually industrial products Other technologies * Household hardware, equipment used for home repair and other work, such as fasteners, wire, plumbing supplies, electrical supplies, utensils, and machine parts *Builders hardware, metal hardware for building fixtures, such as hinges and latches * Hardware (development cooperation), in technology transfer * Drum hardware, used to tension, position, and support the instruments * Military technology, application of technology to warfare * Music hardware, devices other than instruments to create music Entertain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gimbal
A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of the rotation of its support (e.g. vertical in the first animation). For example, on a ship, the gyroscopes, shipboard compasses, stoves, and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling. The gimbal suspension used for mounting compasses and the like is sometimes called a Cardan suspension after Italian mathematician and physicist Gerolamo Cardano (1501–1576) who described it in detail. However, Cardano did not invent the gimbal, nor did he claim to. The device has been known since antiquity, first described in the 3rd c. BC by Philo of Byzantium, although some modern authors support the view that it may not have a single identifiable inventor. His ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walking Beam
A marine steam engine is a steam engine that is used to power a ship or boat. This article deals mainly with marine steam engines of the reciprocating type, which were in use from the inception of the steamboat in the early 19th century to their last years of large-scale manufacture during World War II. Reciprocating steam engines were progressively replaced in marine applications during the 20th century by steam turbines and marine diesel engines. History The first commercially successful steam engine was developed by Thomas Newcomen in 1712. The steam engine improvements brought forth by James Watt in the later half of the 18th century greatly improved steam engine efficiency and allowed more compact engine arrangements. Successful adaptation of the steam engine to marine applications in England would have to wait until almost a century after Newcomen, when Scottish engineer William Symington built the world's "first practical steamboat", the '' Charlotte Dundas'', in 1802. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landing Gear
Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin Company. For aircraft, Stinton makes the terminology distinction ''undercarriage (British) = landing gear (US)''. For aircraft, the landing gear supports the craft when it is not flying, allowing it to take off, land, and taxi without damage. Wheeled landing gear is the most common, with skis or Seaplane, floats needed to operate from snow/ice/water and skids for vertical operation on land. Retractable undercarriages fold away during flight, which reduces drag (physics), drag, allowing for faster airspeeds. Landing gear must be strong enough to support the aircraft and its design affects the weight, balance and performance. It often comprises three wheels, or wheel-sets, giving a tripod effect. Some unusual land ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Motors
American Motors Corporation (AMC; commonly referred to as American Motors) was an American automobile manufacturing company formed by the mergers and acquisitions, merger of Nash-Kelvinator Corporation and Hudson Motor Car Company on May 1, 1954. At the time, it was the largest corporate merger in U.S. history. American Motors' most similar competitors were those automakers that held similar annual sales levels, such as Studebaker, Packard, Kaiser Motors, and Willys-Overland. Their largest competitors were the Big Three (automobile manufacturers), Big Three—Ford Motor Company, Ford, General Motors, and Chrysler. American Motors' production line included Compact car, small cars—the Rambler American, which began as the Nash Rambler in 1950, AMC Hornet, Hornet, AMC Gremlin, Gremlin, and AMC Pacer, Pacer; intermediate car, intermediate and full-size car, full-sized cars, including the AMC Ambassador, Ambassador, Rambler Classic, AMC Rebel, Rebel, and AMC Matador, Matador; musc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grease (lubricant)
Grease is a solid or semisolid lubricant formed as a dispersion of thickening agents in a liquid lubricant. Grease generally consists of a soap emulsified with mineral or vegetable oil. A common feature of greases is that they possess high initial viscosities, which upon the application of shear, drop to give the effect of an oil-lubricated bearing of approximately the same viscosity as the base oil used in the grease. This change in viscosity is called shear thinning. Grease is sometimes used to describe lubricating materials that are simply soft solids or high viscosity liquids, but these materials do not exhibit the shear-thinning properties characteristic of the classical grease. For example, petroleum jellies such as Vaseline are not generally classified as greases. Greases are applied to mechanisms that can be lubricated only infrequently and where a lubricating oil would not stay in position. They also act as sealants to prevent the ingress of water and incompressible ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habsburg Monarchy
The Habsburg monarchy, also known as Habsburg Empire, or Habsburg Realm (), was the collection of empires, kingdoms, duchies, counties and other polities (composite monarchy) that were ruled by the House of Habsburg. From the 18th century it is also referred to as the Austrian monarchy, the Austrian Empire () or the Danubian monarchy. The history of the Habsburg monarchy can be traced back to the election of Rudolf I of Germany, Rudolf I as King of the Romans, King of Germany in 1273 and his acquisition of the Duchy of Austria for the Habsburgs in 1282. In 1482, Maximilian I, Holy Roman Emperor, Maximilian I acquired the Habsburg Netherlands, Netherlands through marriage. Both realms passed to his grandson and successor, Charles V, Holy Roman Emperor, Charles V, who also inherited the Monarchy of Spain, Spanish throne and Spanish Empire, its colonial possessions, and thus came to rule the Habsburg empire at its greatest territorial extent. The abdication of Charles V in 1556 led ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bastion
A bastion is a structure projecting outward from the curtain wall of a fortification, most commonly angular in shape and positioned at the corners of the fort. The fully developed bastion consists of two faces and two flanks, with fire from the flanks being able to protect the curtain wall and the adjacent bastions. Compared with the medieval fortified towers they replaced, bastion fortifications offered a greater degree of passive resistance and more scope for ranged defence in the age of gunpowder artillery. As military architecture, the bastion is one element in the style of fortification dominant from the mid 16th to mid 19th centuries. Evolution By the middle of the 15th century, artillery pieces had become powerful enough to make the traditional medieval round tower and curtain wall obsolete. This was exemplified by the campaigns of Charles VII of France who reduced the towns and castles held by the English during the latter stages of the Hundred Years War, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacis
A glacis (, ) in military engineering is an artificial slope as part of a medieval castle or in early modern fortresses. They may be constructed of earth as a temporary structure or of stone in more permanent structure. More generally, a glacis is any slope, natural or artificial, which fulfils the above requirements. The etymology of this French word suggests a slope made dangerous with ice, hence the relationship with ''glacier''. A ''glacis plate'' is the sloped front-most section of the hull of a tank or other armoured fighting vehicle. Ancient fortifications A glacis could also appear in ancient fortresses, such as the one the ancient Egyptians built at Semna in Nubia. Here it was used by them to prevent enemy siege engines from weakening defensive walls. Hillforts in Britain started to incorporate glacis around 350 BC. Those at Maiden Castle, Dorset were high. Medieval fortifications Glacises, also called taluses, were incorporated into medieval fortifications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
