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Rack And Pinion
rack and pinion is a type of linear actuator that comprises a circular gear (the '' pinion'') engaging a linear gear (the ''rack''). Together, they convert between rotational motion and linear motion: rotating the pinion causes the rack to be driven in a line. Conversely, moving the rack linearly will cause the pinion to rotate. The rack and pinion mechanism is used in rack railways, where the pinion mounted on a locomotive or a railroad car engages a rack usually placed between the rails, and helps to move the train up a steep gradient. It is also used in arbor presses and drill presses, where the pinion is connected to a lever and displaces a vertical rack (the ram). In pipelines and other industrial piping systems, a rack displaced by a linear actuator turns a pinion to open or close a valve. Stairlifts, lock gates, electric gates, and the mechanical steering mechanism of cars are other notable applications. The term "rack and pinion" may be used also when the rac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rack And Pinion Animation
Rack or racks may refer to: Storage, support and transportation * Amp rack, a piece of furniture in which amplifiers are mounted * Autorack or auto carrier, for transporting vehicles in freight trains * Baker's rack, for bread and other baked goods * Bicycle rack: ** Bicycle parking rack ** Bicycle stand, for holding bicycles in service, storage, or transport ** The luggage carrier of a bicycle * Bustle rack, a type of storage bin mounted on armored fighting vehicles * Clothes rack, or clothes horse * hatstand, also known as a coat rack, hall rack, or hat rack * Drum rack, part of a drum kit * Drying rack, for clothing * Ejector rack or hardpoint for attaching external loads to an aircraft * Firearm rack * Flat rack container, a type of railroad freight car * Hay rack, for feeding animals * Laboratory drying rack, a for hanging and draining glassware * Music rack or music stand, to hold sheet music for performance * Newspaper rack, a newspaper vending machine * Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lock Gate
A lock is a device used for raising and lowering boats, ships and other watercraft between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a chamber in a permanently fixed position in which the water level can be varied. (In a caisson lock, a boat lift, or on a canal inclined plane, it is the chamber itself (usually then called a caisson) that rises and falls.) Locks are used to make a river more easily navigable, or to allow a canal to cross land that is not level. Over time, more and larger locks have been used in canals to allow a more direct route to be taken. History Ancient Egypt In Ancient Egypt, the river-locks was probably part of the Canal of the Pharaohs: Ptolemy II is credited by some for being the first to solve the problem of keeping the Nile free of salt water when his engineers invented the lock around 274/273 BC. Ancient China During 960–1279 CE, the natural extension of the flash lock, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ottoman Empire
The Ottoman Empire (), also called the Turkish Empire, was an empire, imperial realm that controlled much of Southeast Europe, West Asia, and North Africa from the 14th to early 20th centuries; it also controlled parts of southeastern Central Europe, between the early 16th and early 18th centuries. The empire emerged from a Anatolian beyliks, ''beylik'', or principality, founded in northwestern Anatolia in by the Turkoman (ethnonym), Turkoman tribal leader Osman I. His successors Ottoman wars in Europe, conquered much of Anatolia and expanded into the Balkans by the mid-14th century, transforming their petty kingdom into a transcontinental empire. The Ottomans ended the Byzantine Empire with the Fall of Constantinople, conquest of Constantinople in 1453 by Mehmed II. With its capital at History of Istanbul#Ottoman Empire, Constantinople (modern-day Istanbul) and control over a significant portion of the Mediterranean Basin, the Ottoman Empire was at the centre of interacti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wu Pei Chih
The ''Wubei Zhi'' (; ''Treatise on Armament Technology'' or ''Records of Armaments and Military Provisions''), also commonly known by its Japanese translated name Bubishi, is a military book in Chinese history. It was compiled in 1621 by （茅元儀 ''Máo Yuányí''; 1594–1640?), an officer of waterborne troops in the Ming dynasty. The ''Wubei Zhi'' contains 240 volumes, 10,405 pages, and more than 200,000 Chinese characters. Structure ''Wubei Zhi'' consists of five sections, "Bing Jue Ping", "Zhan Lue Kao", "Zhen Lian Zhi", "Jun Zi Sheng", and "Zhan Du Zai". *"Bing Jue Ping" (Commentary on Military Formulae) Containing 18 chapters, this section includes military theories from significant figures including, but not limited to, Sun Tzu. Some of these theories date back to the last years of the Eastern Zhou dynasty, more than 1,800 years before the editor. *"Zhan Lue Kao" (Consideration of Tactics) This section consists of 31 chapters, and describes more than 600 specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ottoman Weapons
Military of the Ottoman Empire, Military forces of the Ottoman Empire used a variety of weapons throughout the centuries. The armoury in Topkapı Palace has a large collection showing select items. Yatagan The Yatagan (''yatağan'') makes its appearance in the second half of the 16th century, and is an infantry weapon in which the hilt is generally made of bone or ivory and the pommel is flared. Its short, slightly curved blade is sharp on one edge and comes to a fine point. This form continues unchanged until the end of the 19th century. The yatagan sword was widely used in both the Ottoman army and navy especially for the Janissaries as they were signature weapon for the corps. Kilij The Ottoman cavalry sabre, or kilij (, ), is the Ottoman variant of the Turko-Mongol sabres originating in Central Asia. It was designed for mounted close combat, which was preferred by Turkish and Mamluke troops. It was a one-handed saber with a slight curvature enough to cut and thrust effec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matchlock
A matchlock or firelock is a historical type of firearm wherein the gunpowder is ignited by a burning piece of flammable cord or twine that is in contact with the gunpowder through a mechanism that the musketeer activates by pulling a lever or Trigger (firearms), trigger with their finger. This firing mechanism was an improvement over the hand cannon, which lacked a trigger and required the musketeer or an assistant to apply a match directly to the gunpowder by hand. The matchlock mechanism allowed the musketeer to apply the match himself without losing his concentration. Description The classic matchlock gun held a burning slow match in a clamp at the end of a small curved lever known as the ''serpentine''. Upon the pull of a lever (or in later models a trigger) protruding from the bottom of the gun and connected to the serpentine, the clamp dropped down, lowering the smoldering match into the flash pan and igniting the priming powder. The flash from the primer traveled throug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arquebus
An arquebus ( ) is a form of long gun that appeared in Europe and the Ottoman Empire during the 15th century. An infantryman armed with an arquebus is called an arquebusier. The term ''arquebus'' was applied to many different forms of firearms from the 15th to 17th centuries, but it originally referred to "a hand cannon, hand-gun with a hook-like projection or lug on its under surface, useful for steadying it against battlements or other objects when firing". These "hook guns" were in their earliest forms defensive weapons mounted on German city walls in the early 15th century. The addition of a shoulder stock, priming pan, and matchlock mechanism in the late 15th century turned the arquebus into a handheld firearm and also the first firearm equipped with a trigger. The exact dating of the matchlock's appearance is disputed. It could have appeared in the Ottoman Empire as early as 1465 and in Europe a little before 1475. The heavy arquebus, which was then called a musket, was d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Before Christ
The terms (AD) and before Christ (BC) are used when designating years in the Gregorian calendar, Gregorian and Julian calendar, Julian calendars. The term is Medieval Latin and means "in the year of the Lord" but is often presented using "our Lord" instead of "the Lord", taken from the full original phrase "", which translates to "in the year of our Lord Jesus Christ". The form "BC" is specific to English language, English, and equivalent abbreviations are used in other languages: the Latin (language), Latin form, rarely used in English, is (ACN) or (AC). This calendar era takes as its epoch (date reference), epoch the traditionally reckoned year of the annunciation, conception or Nativity of Jesus, birth of Jesus. Years ''AD'' are counted forward since that epoch and years ''BC'' are counted backward from the epoch. There is no year zero in this scheme; thus the year AD 1 immediately follows the year 1 BC. This dating system was devised in 525 by Dionysius Exiguus but was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antikythera Mechanism
The Antikythera mechanism ( , ) is an Ancient Greece, Ancient Greek hand-powered orrery (model of the Solar System). It is the oldest known example of an Analog computer, analogue computer. It could be used to predict astronomy, astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games similar to an Olympiad, the cycle of the ancient Olympic Games. The artefact was among wreckage retrieved from Antikythera wreck, a shipwreck off the coast of the Greek island Antikythera in 1901. In 1902, during a visit to the National Archaeological Museum, Athens, National Archaeological Museum in Athens, it was noticed by Greek politician Spyridon Stais as containing a gear, prompting the first study of the fragment by his cousin, Valerios Stais, the museum director. The device, housed in the remains of a wooden-framed case of (uncertain) overall size , was found as one lump, later separated into three main fragments which ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South-pointing Chariot
The south-pointing chariot (or carriage) was an ancient Chinese two-wheeled vehicle that carried a movable pointer to indicate the south, no matter how the chariot turned. Usually, the pointer took the form of a doll or figure with an outstretched arm. The chariot was supposedly used as a non-magnetic compass for navigation and may also have had other purposes. The ancient Chinese invented a mobile-like armored cart in the 5th century BC called the Dongwu Che (). It was used for the purpose of protecting warriors on the battlefield. The Chinese war wagon was designed as a kind of mobile protective cart with a shed-like roof. It would serve to be rolled up to city fortifications to provide protection for sappers digging underneath to weaken a wall's foundation. The early Chinese war wagon became the basis of technologies for the making of ancient Chinese south-pointing chariots. There are legends of earlier south-pointing chariots, but the first reliably documented one was creat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheelset (rail Transport)
A wheelset is a pair of railroad car, railroad vehicle Train wheel, wheels mounted rigidly on an Axle#Vehicle axles, axle. Wheelsets are often mounted in a bogie ("List of railroad truck parts, truck" in North America) – a pivoted frame assembly holding at least two wheelsets – at each end of the vehicle. Most modern goods wagon, freight cars and Railroad car#Passenger cars, passenger cars have bogies each with two wheelsets, but three wheelsets (or more) are used in bogies of freight cars that carry heavy loads, and three-wheelset bogies are under some passenger cars. Four-wheeled goods wagons that were once near-universal in Europe and Great Britain and their colonies have only two wheelsets; in recent decades such vehicles have become less common as trainloads have become heavier. Conical wheel-tread Most train wheels have a cone (mathematics), conical taper of about 1 in 20 to enable the wheelset to follow Civil engineering#Surveying, curves with less ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canal
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow under atmospheric pressure, and can be thought of as artificial rivers. In most cases, a canal has a series of dams and locks that create reservoirs of low speed current flow. These reservoirs are referred to as ''slack water levels'', often just called ''levels''. A canal can be called a navigation canal when it parallels a natural river and shares part of the latter's discharges and drainage basin, and leverages its resources by building dams and locks to increase and lengthen its stretches of slack water levels while staying in its valley. A canal can cut across a drainage divide atop a ridge, generally requiring an external water source above the highest elevation. The best-known example of such a canal is the Panama Can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
