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Micrometer (device)
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for accurate measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers. Micrometers are usually, but not always, in the form of calipers (opposing ends joined by a frame). The spindle is a very accurately machined screw and the object to be measured is placed between the spindle and the anvil. The spindle is moved by turning the ratchet knob or thimble until the object to be measured is lightly touched by both the spindle and the anvil. Micrometers are also used in telescopes and microscopes to measure the apparent diameter of celestial bodies or microscopic objects. The micrometer used with a telescope was invented about 1638 by William Gascoigne, an English astronomer. History The word ''micrometer'' is a neoclassical coinage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mahr Micromar 40A 0–25 Mm Micrometer
In Islam, a mahr (in ar, مهر; fa, مهريه; tr, mehir; sw, mahari; also transliterated ''mehr'', ''meher'', ''mehrieh'', or ''mahriyeh'') is the obligation, in the form of money or possessions paid by the groom, to the bride at the time of Islamic marriage (payment also has circumstances on when and how to pay). While the ''mahr'' is often money, it can also be anything agreed upon by the bride such as jewelry, home goods, furniture, a dwelling or some land. Mahr is typically specified in the marriage contract signed upon marriage. "Dower" is the English translation that comes closest to Islamic meaning of mahr, as "dower" refers to the payment from the husband or his family to the wife, especially to support her in the event of his death, although subsequent to marriage the wife also acquires inheritance rights. However, mahr is distinct from dower in two ways: 1) mahr is legally required for all Islamic marriages while dower is optional, and 2) mahr is required to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Gascoigne (scientist)
William Gascoigne (1612 – 2 July 1644) was an English astronomer, mathematician and maker of scientific instruments from Middleton, Leeds who invented the micrometer and the telescopic sight. He was one of a group of astronomers in the north of England who followed the astronomy of Johannes Kepler, which included Jeremiah Horrocks and William Crabtree. Life and work Gascoigne was born in Middleton, Leeds in 1612, the son of a minor country gentleman. His father was Henry Gascoigne, Esq., of Thorpe-on-the-Hill in the parish of Rothwell, near Leeds, Yorkshire. His mother was Margaret Jane, daughter of William Cartwright. Little is known of his early life. He claimed he was educated at the University of Oxford, although no record of this has been found. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis De Tousard
Louis de Tousard (1749-1817) was a French artillerist who served in the American Continental Army under La Fayette, and later was given a US commission. Tousard wrote two very influential books: one was a proposal for a school for officers that became the blueprint for West Point, and the other was a manual for artillery officers that became standard in the young army.. Biography He is the brother of Antoine Étienne de Tousard. Educated at the Strasbourg school of artillery,. Tousard served with the Continental Army between 1777-1778 and lost an arm due to wound received in the Battle of Rhode Island. He was decorated with the Order of Saint Louis on his return to France. After being briefly imprisoned during the French Revolution in 1793 at Prison de l'Abbaye, he returned to the US in 1795 where he received a commission as a major in the 2nd U.S. Artillery Regiment in the Corps of Artillerists and Engineers. By 1800 he was a lieutenant colonel and Inspector of Artillery. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Baptiste Vaquette De Gribeauval
Lieutenant General Jean-Baptiste Vaquette de Gribeauval (15 September 1715 – 9 May 1789) was a French artillery officer and engineer who revolutionised the French cannon, creating a new production system that allowed for lighter, more uniform guns without sacrificing range. His Gribeauval system superseded the de Vallière system. These guns proved essential to French military victories during the Napoleonic Wars. Gribeauval is credited as the earliest known advocate for the interchangeability of gun parts. He is thus one of the principal influences on the later development (over many decades by many people) of interchangeable manufacture. Early life Jean-Baptiste was born in Amiens, the son of a magistrate. He entered the French royal artillery in 1732 as a volunteer, and became an officer in 1735. For nearly twenty years regimental duty and scientific work occupied him, and in 1752 he became captain of a company of miners.Summerfield (2011) ''SOJ-2'', p. 20 In 1755, he was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interchangeable Parts
Interchangeable parts are parts (components) that are identical for practical purposes. They are made to specifications that ensure that they are so nearly identical that they will fit into any assembly of the same type. One such part can freely replace another, without any custom fitting, such as filing. This interchangeability allows easy assembly of new devices, and easier repair of existing devices, while minimizing both the time and skill required of the person doing the assembly or repair. The concept of interchangeability was crucial to the introduction of the assembly line at the beginning of the 20th century, and has become an important element of some modern manufacturing but is missing from other important industries. Interchangeability of parts was achieved by combining a number of innovations and improvements in machining operations and the invention of several machine tools, such as the slide rest lathe, screw-cutting lathe, turret lathe, milling machine and m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toolroom
Tool and die makers are highly skilled crafters working in the manufacturing industries. Variations on the name include tool maker, toolmaker, die maker, diemaker, mold maker, moldmaker or tool jig and die-maker depending on which area of concentration or industry an individual works in. Tool and die makers work primarily in toolroom environments—sometimes literally in one room but more often in an environment with flexible, semipermeable boundaries from production work. They are skilled artisans ( craftspeople) who typically learn their trade through a combination of academic coursework and with substantial period of on-the-job training that is functionally an apprenticeship. They make jigs, fixtures, dies, molds, machine tools, cutting tools, gauges, and other tools used in manufacturing processes. Divisions The main divisions of the tool & die industry include: *Die casting *Dies *Fixtures *Forging * Gauges *Jigs * Metal working * Moulding Job description Traditionally, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edward W
Edward is an English given name. It is derived from the Anglo-Saxon name ''Ēadweard'', composed of the elements '' ēad'' "wealth, fortune; prosperous" and '' weard'' "guardian, protector”. History The name Edward was very popular in Anglo-Saxon England, but the rule of the Norman and Plantagenet dynasties had effectively ended its use amongst the upper classes. The popularity of the name was revived when Henry III named his firstborn son, the future Edward I, as part of his efforts to promote a cult around Edward the Confessor, for whom Henry had a deep admiration. Variant forms The name has been adopted in the Iberian peninsula since the 15th century, due to Edward, King of Portugal, whose mother was English. The Spanish/Portuguese forms of the name are Eduardo and Duarte. Other variant forms include French Édouard, Italian Edoardo and Odoardo, German, Dutch, Czech and Romanian Eduard and Scandinavian Edvard. Short forms include Ed, Eddy, Eddie, Ted, Teddy an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brown & Sharpe
Brown & Sharpe is a division of Hexagon AB, a Swedish multinational corporation focused mainly on metrological tools and technology. During the 19th and 20th centuries, Brown & Sharpe was one of the best-known and most influential machine tool builders and was a leading manufacturer of instruments for machinists (such as micrometers and indicators). Its reputation and influence were such that its name is often considered to be inseparably paired with certain industrial standards that it helped establish, including: * The American wire gauge (AWG) standards for wire; * The Brown & Sharpe taper in machine tool spindle tapers; and * The Brown & Sharpe worm threadform for worm gears. Since being acquired by Hexagon Metrology in 2001, Brown and Sharpe has concentrated exclusively on metrology equipment. History Founding (1833) and early years Brown & Sharpe was founded in 1833 on South Main Street in Providence, Rhode Island by David Brown and his son Joseph R. Brown. The elde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris
Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, fashion, gastronomy, and science. For its leading role in the arts and sciences, as well as its very early system of street lighting, in the 19th century it became known as "the City of Light". Like London, prior to the Second World War, it was also sometimes called the capital of the world. The City of Paris is the centre of the Île-de-France region, or Paris Region, with an estimated population of 12,262,544 in 2019, or about 19% of the population of France, making the region France's primate city. The Paris Region had a GDP of €739 billion ($743 billion) in 2019, which is the highest in Europe. According to the Economis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Laurent Palmer
Jean may refer to: People * Jean (female given name) * Jean (male given name) * Jean (surname) Fictional characters * Jean Grey, a Marvel Comics character * Jean Valjean, fictional character in novel ''Les Misérables'' and its adaptations * Jean Pierre Polnareff, a fictional character from ''JoJo's Bizarre Adventure'' Places * Jean, Nevada, USA; a town * Jean, Oregon, USA Entertainment * Jean (dog), a female collie in silent films * "Jean" (song) (1969), by Rod McKuen, also recorded by Oliver * ''Jean Seberg'' (musical), a 1983 musical by Marvin Hamlisch Other uses * JEAN (programming language) * USS ''Jean'' (ID-1308), American cargo ship c. 1918 * Sternwheeler Jean, a 1938 paddleboat of the Willamette River See also *Jehan * * Gene (other) * Jeanne (other) * Jehanne (other) * Jeans (other) * John (other) John is a common English name and surname: * John (given name) * John (surname) John may also refer to: N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Whitworth
Sir Joseph Whitworth, 1st Baronet (21 December 1803 – 22 January 1887) was an English engineer, entrepreneur, inventor and philanthropist. In 1841, he devised the British Standard Whitworth system, which created an accepted standard for screw threads. Whitworth also created the Whitworth rifle, often called the "sharpshooter" because of its accuracy, which is considered one of the earliest examples of a sniper rifle. Whitworth was created a baronet by Queen Victoria in 1869. Upon his death in 1887, Whitworth bequeathed much of his fortune for the people of Manchester, with the Whitworth Art Gallery and Christie Hospital partly funded by Whitworth's money. Whitworth Street and Whitworth Hall in Manchester are named in his honour. Whitworth's company merged with the W.G. Armstrong & Mitchell Company to become Armstrong Whitworth in 1897. Biography Early life Whitworth was born in John Street, Stockport, Cheshire, where the Stockport Courthouse is today. The site is mark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accuracy And Precision
Accuracy and precision are two measures of '' observational error''. ''Accuracy'' is how close a given set of measurements (observations or readings) are to their '' true value'', while ''precision'' is how close the measurements are to each other. In other words, ''precision'' is a description of '' random errors'', a measure of statistical variability. ''Accuracy'' has two definitions: # More commonly, it is a description of only ''systematic errors'', a measure of statistical bias of a given measure of central tendency; low accuracy causes a difference between a result and a true value; ISO calls this ''trueness''. # Alternatively, ISO defines accuracy as describing a combination of both types of observational error (random and systematic), so high accuracy requires both high precision and high trueness. In the first, more common definition of "accuracy" above, the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
