145 relations: Aerospace, Alexandrian school, American Gear Manufacturers Association, Angular frequency, Antikythera mechanism, Archimedes, Astronomy, Automatic transmission, Backlash (engineering), Belt (mechanical), Bevel gear, Broaching (metalworking), China, Citroën Type A, Continuously variable transmission, Coprime integers, Cotton gin, Crank (mechanism), Cycloid gear, Cycloidal drive, Derailleur gears, Derek J. de Solla Price, Die casting, Differential (mechanical device), Dimension, Donald Hill, Drive shaft, Egypt (Roman province), Electromagnetism, Escapement, Fillet (mechanics), Flywheel, Frequency, Friction, Frustum, Gear, Gear cutting, Gear shaping, Gear train, Greatest common divisor, Heat treating, Helix, Hermetic seal, Hero of Alexandria, Herringbone gear, Hobbing, Hub gear, Hyperboloid, Imperial units, Inch, ..., Indian subcontinent, Injection moulding, Integer, Investment casting, Involute, Involute gear, Irfan Habib, Irrational number, Ismail al-Jazari, Issus (genus), Issus coleoptratus, James Clerk Maxwell, James Watt, Joseph Needham, Kinematic chain, List of gear nomenclature, Luoyang Museum, Ma Jun, Machine (mechanical), Machine head, Machining, Magnetic coupling, Manual transmission, McGraw-Hill Education, McGraw-Hill Encyclopedia of Science & Technology, Mechanical advantage, Mechanical efficiency, Metric system, Millimetre, Milling (machining), Modern physics, Motion control, NASA, Near net shape, Noise barrier, Noise control, Oscillation, Pearson Education, Pinion, Polymath, Potentiometer, Powder metallurgy, Power (physics), Powertrain, Pressure angle, Prime number, Ptolemaic Kingdom, Pulley, Quantum mechanics, Quench press, Rack and pinion, Rack railway, Radial shaft seal, Radian per second, Ratio, Reciprocating motion, Revolutions per minute, Roadway noise, Robotics, Roller chain, Rotation, Rotation around a fixed axis, Rotational speed, Saddle point, Salisbury cathedral clock, Sand casting, Screw, Simple machine, Sintering, Sound intensity, South-pointing chariot, Springer Science+Business Media, Sprocket, Steam engine, Steering, String instrument, Sun and planet gear, Superposition principle, The Verge, TheFreeDictionary.com, Thrust, Thrust bearing, Torque, Toughness, Traction (engineering), Translation (geometry), Transmission (mechanics), Undercut (manufacturing), Unit of measurement, University of Cambridge, Wave–particle duality, Wear, Worm drive, Zhou dynasty, 3D printing. Expand index (95 more) » « Shrink index
Aerospace is the human effort in science, engineering and business to fly in the atmosphere of Earth (aeronautics) and surrounding space (astronautics).
The Alexandrian school is a collective designation for certain tendencies in literature, philosophy, medicine, and the sciences that developed in the Hellenistic cultural center of Alexandria, Egypt during the Hellenistic and Roman periods.
The American Gear Manufacturers Association or AGMA is the trade group of companies involved in gears, couplings and related power transmission components and equipment.
In physics, angular frequency ω (also referred to by the terms angular speed, radial frequency, circular frequency, orbital frequency, radian frequency, and pulsatance) is a scalar measure of rotation rate.
The Antikythera mechanism is an ancient Greek analogue computer and orrery used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance.
Archimedes of Syracuse (Ἀρχιμήδης) was a Greek mathematician, physicist, engineer, inventor, and astronomer.
Astronomy (from ἀστρονομία) is a natural science that studies celestial objects and phenomena.
An automatic transmission, also called auto, self-shifting transmission, n-speed automatic (where n is its number of forward gear ratios), or AT, is a type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually.
In mechanical engineering, backlash, sometimes called lash or play, is a clearance or lost motion in a mechanism caused by gaps between the parts.
A belt is a loop of flexible material used to link two or more rotating shafts mechanically, most often parallel.
Bevel gears are gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped.
Broaching is a machining process that uses a toothed tool, called a broach, to remove material.
China, officially the People's Republic of China (PRC), is a unitary one-party sovereign state in East Asia and the world's most populous country, with a population of around /1e9 round 3 billion.
The Citroën Type A was produced from June 1919 to December 1921 in Paris, France.
A continuously variable transmission (CVT), also known as a single-speed transmission, stepless transmission, pulley transmission, or, in case of motorcycles, a twist-and-go, is an automatic transmission that can change seamlessly through a continuous range of effective gear ratios.
In number theory, two integers and are said to be relatively prime, mutually prime, or coprime (also written co-prime) if the only positive integer (factor) that divides both of them is 1.
A cotton gin is a machine that quickly and easily separates cotton fibers from their seeds, enabling much greater productivity than manual cotton separation.
A crank is an arm attached at a right angle to a rotating shaft by which reciprocating motion is imparted to or received from the shaft.
The cycloidal gear profile is a form of toothed gear used in mechanical clocks, rather than the involute gear form used for most other gears.
A cycloidal drive or cycloidal speed reducer is a mechanism for reducing the speed of an input shaft by a certain ratio.
Derailleur gears are a variable-ratio transmission system commonly used on bicycles, consisting of a chain, multiple sprockets of different sizes, and a mechanism to move the chain from one sprocket to another.
Derek John de Solla Price (22 January 1922 – 3 September 1983) was a physicist, historian of science, and information scientist, credited as the father of scientometrics.
Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity.
A differential is a gear train with three shafts that has the property that the rotational speed of one shaft is the average of the speeds of the others, or a fixed multiple of that average.
In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it.
Donald Routledge Hill (August 6, 1922 – May 30, 1994)D.
A drive shaft, driveshaft, driving shaft, propeller shaft (prop shaft), or Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement between them.
The Roman province of Egypt (Aigyptos) was established in 30 BC after Octavian (the future emperor Augustus) defeated his rival Mark Antony, deposed Queen Cleopatra VII, and annexed the Ptolemaic Kingdom of Egypt to the Roman Empire.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles.
An escapement is a device in mechanical watches and clocks that transfers energy to the timekeeping element (the "impulse action") and allows the number of its oscillations to be counted (the "locking action").
In mechanical engineering, a fillet is a rounding of an interior or exterior corner of a part design.
A flywheel is a mechanical device specifically designed to efficiently store rotational energy.
Frequency is the number of occurrences of a repeating event per unit of time.
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
In geometry, a frustum (plural: frusta or frustums) is the portion of a solid (normally a cone or pyramid) that lies between one or two parallel planes cutting it.
A gear or cogwheel is a rotating machine part having cut like teeth, or cogs, which mesh with another toothed part to transmit torque.
Gear cutting is any machining process for creating a gear.
Gear shaping is a machining process for creating teeth on a gear using a cutter.
A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage.
In mathematics, the greatest common divisor (gcd) of two or more integers, which are not all zero, is the largest positive integer that divides each of the integers.
Heat treating (or heat treatment) is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material.
A helix, plural helixes or helices, is a type of smooth space curve, i.e. a curve in three-dimensional space.
A hermetic seal is any type of sealing that makes a given object airtight (excludes the passage of air, oxygen, or other gases).
Hero of Alexandria (ἭρωνGenitive: Ἥρωνος., Heron ho Alexandreus; also known as Heron of Alexandria; c. 10 AD – c. 70 AD) was a mathematician and engineer who was active in his native city of Alexandria, Roman Egypt.
A herringbone gear, a specific type of double helical gear, is a special type of gear that is a side to side (not face to face) combination of two helical gears of opposite hands.
Hobbing is a machining process for gear cutting, cutting splines, and cutting sprockets on a hobbing machine, which is a special type of milling machine.
A hub gear, internal-gear hub, or just gear hub is a gear ratio changing system commonly used on bicycles that is implemented with planetary or epicyclic gears.
In geometry, a hyperboloid of revolution, sometimes called circular hyperboloid, is a surface that may be generated by rotating a hyperbola around one of its principal axes.
The system of imperial units or the imperial system (also known as British Imperial or Exchequer Standards of 1825) is the system of units first defined in the British Weights and Measures Act of 1824, which was later refined and reduced.
The inch (abbreviation: in or &Prime) is a unit of length in the (British) imperial and United States customary systems of measurement now formally equal to yard but usually understood as of a foot.
The Indian subcontinent is a southern region and peninsula of Asia, mostly situated on the Indian Plate and projecting southwards into the Indian Ocean from the Himalayas.
Injection moulding (British English) or injection molding (American English) is a manufacturing process for producing parts by injecting molten material into a mould.
An integer (from the Latin ''integer'' meaning "whole")Integer 's first literal meaning in Latin is "untouched", from in ("not") plus tangere ("to touch").
Investment casting is an industrial process based on lost-wax casting, one of the oldest known metal-forming techniques.
In the differential geometry of curves, an involute (also known as evolvent) is a curve obtained from another given curve by one of two methods.
The involute gear profile is the most commonly used system for gearing today, with cycloid gearing still used for some specialties such as clocks.
Irfan Habib (born 1931) is an Indian historian of ancient and medieval India, following the approach of Marxist historiography.
In mathematics, the irrational numbers are all the real numbers which are not rational numbers, the latter being the numbers constructed from ratios (or fractions) of integers.
Badīʿ az-Zaman Abū l-ʿIzz ibn Ismāʿīl ibn ar-Razāz al-Jazarī (1136–1206, بديع الزمان أَبُو اَلْعِزِ بْنُ إسْماعِيلِ بْنُ الرِّزاز الجزري) was a Muslim polymath: a scholar, inventor, mechanical engineer, artisan, artist and mathematician.
Issus is a genus of 'planthoppers' belonging to the family Issidae of infraorder Fulgoromorpha of suborder Auchenorrhyncha of order Hemiptera.
Issus coleoptratus is a species of planthopper belonging to the family Issidae.
James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish scientist in the field of mathematical physics.
James Watt (30 January 1736 (19 January 1736 OS) – 25 August 1819) was a Scottish inventor, mechanical engineer, and chemist who improved on Thomas Newcomen's 1712 Newcomen steam engine with his Watt steam engine in 1781, which was fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world.
Noel Joseph Terence Montgomery Needham (9 December 1900 – 24 March 1995) was a British biochemist, historian and sinologist known for his scientific research and writing on the history of Chinese science and technology.
In mechanical engineering, a kinematic chain is an assembly of rigid bodies connected by joints to provide constrained (or desired) motion that is the mathematical model for a mechanical system.
The addendum is the height by which a tooth of a gear projects beyond (outside for external, or inside for internal) the standard pitch circle or pitch line; also, the radial distance between the pitch diameter and the outside diameter.
Luoyang Museum is a historical museum in Luoyang, Henan Province, China.
Ma Jun (220–265), courtesy name Deheng, was a Chinese mechanical engineer and politician who lived in the state of Cao Wei during the Three Kingdoms period of China.
Machines employ power to achieve desired forces and movement (motion).
A machine head (also referred to as a tuning machine, tuner, or gear head) is a geared apparatus for tuning stringed musical instruments by adjusting string tension.
Machining is any of various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process.
A magnetic coupling is a coupling that transfers torque from one shaft, but using a magnetic field rather than a physical mechanical connection.
A manual transmission, also known as a manual gearbox, a standard transmission or colloquially in some countries (e.g. the United States) as a stick shift is a type of transmission used in motor vehicle applications.
McGraw-Hill Education (MHE) is a learning science company and one of the "big three" educational publishers that provides customized educational content, software, and services for pre-K through postgraduate education.
The McGraw-Hill Encyclopedia of Science & Technology is an English-language multivolume encyclopedia, specifically focused on scientific and technical subjects, and published by McGraw-Hill Education.
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system.
Mechanical efficiency measures the effectiveness of a machine in transforming the energy and power that is input to the device into an output force and movement.
The metric system is an internationally adopted decimal system of measurement.
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length.
Milling is the machining process of using rotary cutters to remove material from a workpiece by advancing (or feeding) the cutter into the workpiece at a certain direction.
Modern physics is the post-Newtonian conception of physics.
Motion control is a sub-field of automation, encompassing the systems or sub-systems involved in moving parts of machines in a controlled manner.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
Near net shape is an industrial manufacturing technique.
A noise barrier (also called a soundwall, noise wall, sound berm, sound barrier, or acoustical barrier) is an exterior structure designed to protect inhabitants of sensitive land use areas from noise pollution.
Noise control or noise mitigation is a set of strategies to reduce noise pollution or to reduce the impact of that noise, whether outdoors or indoors.
Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states.
Pearson Education (see also Pearson PLC) is a British-owned education publishing and assessment service to schools and corporations, as well as directly to students.
A pinion is a round gear—usually to the smaller of two meshed gears—used in several applications, including drivetrain and rack and pinion systems.
A polymath (πολυμαθής,, "having learned much,"The term was first recorded in written English in the early seventeenth century Latin: uomo universalis, "universal man") is a person whose expertise spans a significant number of different subject areas—such a person is known to draw on complex bodies of knowledge to solve specific problems.
A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider.
Powder metallurgy (PM) is a term covering a wide range of ways in which materials or components are made from metal powders.
In physics, power is the rate of doing work, the amount of energy transferred per unit time.
In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air.
Pressure angle in relation to gear teeth, also known as the angle of obliquity, is the angle between the tooth face and the gear wheel tangent.
A prime number (or a prime) is a natural number greater than 1 that cannot be formed by multiplying two smaller natural numbers.
The Ptolemaic Kingdom (Πτολεμαϊκὴ βασιλεία, Ptolemaïkḕ basileía) was a Hellenistic kingdom based in Egypt.
A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable or belt, or transfer of power between the shaft and cable or belt.
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
A quench press is a machine that uses concentrated forces to hold an object as it is quenched.
A rack and pinion is a type of linear actuator that comprises a pair of gears which convert rotational motion into linear motion.
A rack railway (also rack-and-pinion railway, cog railway, or cogwheel railway) is a steep grade railway with a toothed rack rail, usually between the running rails.
Radial shaft seals, also known as lip seals, are used to seal rotary elements, such as a shaft or rotating bore.
The radian per second (symbol: rad·s−1 or rad/s) is the SI unit of rotational speed (angular velocity), commonly denoted by the Greek letter ω (omega).
In mathematics, a ratio is a relationship between two numbers indicating how many times the first number contains the second.
Reciprocating motion, also called reciprocation, is a repetitive up-and-down or back-and-forth linear motion.
Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min) is the number of turns in one minute.
Roadway noise is the collective sound energy emanating from motor vehicles.
Robotics is an interdisciplinary branch of engineering and science that includes mechanical engineering, electronics engineering, computer science, and others.
Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, printing presses, cars, motorcycles, and bicycles.
A rotation is a circular movement of an object around a center (or point) of rotation.
Rotation around a fixed axis or about a fixed axis of revolution or motion with respect to a fixed axis of rotation is a special case of rotational motion.
Rotational speed (or speed of revolution) of an object rotating around an axis is the number of turns of the object divided by time, specified as revolutions per minute (rpm), cycles per second (cps), radians per second (rad/s), etc..
In mathematics, a saddle point or minimax point is a point on the surface of the graph of a function where the slopes (derivatives) of orthogonal function components defining the surface become zero (a stationary point) but are not a local extremum on both axes.
The Salisbury cathedral clock is a large iron-framed clock without a dial located in the aisle of Salisbury Cathedral.
Sand casting, also known as sand molded casting, is a metal casting process characterized by using sand as the mold material.
A screw is a type of fastener, in some ways similar to a bolt (see Differentiation between bolt and screw below), typically made of metal, and characterized by a helical ridge, known as a male thread (external thread).
A simple machine is a mechanical device that changes the direction or magnitude of a force.
Clinker nodules produced by sintering Sintering is the process of compacting and forming a solid mass of material by heat or pressure without melting it to the point of liquefaction.
Sound intensity level also known as acoustic intensity is defined as the power carried by sound waves per unit area in a direction perpendicular to that area.
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.
Springer Science+Business Media or Springer, part of Springer Nature since 2015, is a global publishing company that publishes books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing.
A sprocket or sprocket-wheel is a profiled wheel with teeth, or cogs, that mesh with a chain, track or other perforated or indented material.
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.
Steering is the collection of components, linkages, etc.
String instruments, stringed instruments, or chordophones are musical instruments that produce sound from vibrating strings when the performer plays or sounds the strings in some manner.
The sun and planet gear is a method of converting reciprocating motion to rotary motion and was used in the first rotative beam engines.
In physics and systems theory, the superposition principle, also known as superposition property, states that, for all linear systems, the net response caused by two or more stimuli is the sum of the responses that would have been caused by each stimulus individually.
The Verge is an American technology news and media network operated by Vox Media.
TheFreeDictionary.com is an American online dictionary and encyclopedia that gathers information from a variety of sources.
Thrust is a reaction force described quantitatively by Newton's third law.
A thrust bearing is a particular type of rotary bearing.
Torque, moment, or moment of force is rotational force.
In materials science and metallurgy, toughness is the ability of a material to absorb energy and plastically deform without fracturing.
Traction, or tractive force, is the force used to generate motion between a body and a tangential surface, through the use of dry friction, though the use of shear force of the surface is also commonly used.
In Euclidean geometry, a translation is a geometric transformation that moves every point of a figure or a space by the same distance in a given direction.
A transmission is a machine in a power transmission system, which provides controlled application of the power.
In manufacturing, an undercut is a special type of recessed surface.
A unit of measurement is a definite magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity.
The University of Cambridge (informally Cambridge University)The corporate title of the university is The Chancellor, Masters, and Scholars of the University of Cambridge.
Wave–particle duality is the concept in quantum mechanics that every particle or quantic entity may be partly described in terms not only of particles, but also of waves.
Wear is the damaging, gradual removal or deformation of material at solid surfaces.
A worm drive is a gear arrangement in which a worm (which is a gear in the form of a screw) meshes with a worm gear (which is similar in appearance to a spur gear).
The Zhou dynasty or the Zhou Kingdom was a Chinese dynasty that followed the Shang dynasty and preceded the Qin dynasty.
3D printing is any of various processes in which material is joined or solidified under computer control to create a three-dimensional object, with material being added together (such as liquid molecules or powder grains being fused together).
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