A diagram is needed in this article Image File history File links Diagram_Needed. ...

A linear motor is essentially a multi-phase alternating current (AC) electric motor that has had its stator "unrolled" so that instead of producing a torque (rotation) it produces a linear force along its length. The most common mode of operation is as a Lorentz-type actuator, in which the applied force is linearly proportional to the current and the magnetic field (F = qv × B). City lights viewed in a motion blurred exposure. ... For other kinds of motors, see motor. ... The stator is the fixed part of a rotating machine. ... Torque applied via an adjustable end wrench Relationship between force, torque, and momentum vectors in a rotating system In physics, torque (or often called a moment) can informally be thought of as rotational force or angular force which causes a change in rotational motion. ... This article is about rotation as a movement of a physical body. ... For other uses, see Force (disambiguation). ...

Many designs have been put forward for linear motors, falling into two major categories, low-acceleration and high-acceleration linear motors. Low-acceleration linear motors are suitable for maglev trains and other ground-based transportation applications. High-acceleration linear motors are normally quite short, and are designed to accelerate an object up to a very high speed and then release the object. They are usually used for studies of hypervelocity collisions, as weapons, or as mass drivers for spacecraft propulsion. The high-acceleration motors are usually of the linear induction design (LIM) with an active three-phase winding on one side of the air-gap and a passive conductor plate on the other side. The low-acceleration, high speed and high power motors are usually of the linear synchronous design (LSM), with an active winding on one side of the air-gap and an array of alternate-pole magnets on the other side. These magnets can be permanent magnets or energised magnets. The Transrapid Shangai motor is an LSM. Transrapid Shanghai Maglev Train stopping at terminus Longyang Road station Transrapid Shanghai Maglev Train Inside the Shanghai Transrapid maglev Inside the Shanghai Transrapid maglev VIP section Magnetic levitation transport, or maglev, is a form of transportation that suspends, guides and propels vehicles (especially trains) using electromagnetic force. ... Hypervelocity is usually refered to a very high velocity, such as over 10,000 feet per second. ... For other uses, see Weapon (disambiguation). ... A mass driver for lunar launch (artists conception) A mass driver or electromagnetic catapult is a method of spacecraft propulsion that would use a linear motor to accelerate payloads up to high speeds. ... A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is any method used to change the velocity of spacecraft and artificial satellites. ... Three phase systems have 3 waveforms (usually carrying power) that are 2/3π radians (120 degrees,1/3 of a cycle) offset in time. ... Transrapid at the Emsland test facility Transrapid is a German monorail system using magnetic levitation. ...

When a linear motor is used to accelerate beams of ions or subatomic particles, it is called a particle accelerator. The design is usually rather different as the particles move close to the speed of light and are usually electrically charged. This article is about the electrically charged particle. ... Helium atom (schematic) Showing two protons (red), two neutrons (green) and two electrons (yellow). ... For the DC Comics Superhero also called Atom Smasher, see Albert Rothstein. ... The speed of light in a vacuum is an important physical constant denoted by the letter c for constant or the Latin word celeritas meaning swiftness.[1] It is the speed of all electromagnetic radiation, including visible light, in a vacuum. ... Electric charge is a fundamental property of some subatomic particles, which determines their electromagnetic interactions. ...

Low acceleration

ART trains propel themselves using an aluminium induction strip placed between the rails.

The history of linear electric motors can be traced back at least as far as the 1840s, to the work of Charles Wheatstone at King's College in London [1], but Wheatstone's model was too inefficient to be practical. A feasible linear induction motor is described in the US patent 732312 ( 1905 - inventor Alfred Zehden of Frankfurt-am-Main ), for driving trains or lifts. The German engineer Hermann Kemper built a working model in 1935 [2]. In the late 1940s, professor Eric Laithwaite of Imperial College in London developed the first full-size working model. In his design, and in most low-acceleration designs, the force is produced by a moving linear electromagnetic field acting on conductors in the field. Any conductor, be it a loop, a coil or simply a piece of plate metal, that is placed in this field will have eddy currents induced in it thus creating an opposing electromagnetic field. The two opposing fields will repel each other, thus forcing the conductor away from the stator and carrying it along in the direction of the moving magnetic field. Image File history File links Download high-resolution version (831x541, 172 KB) Taken From: english wikipedia File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Linear motor Bombardier Advanced Rapid Transit AirTrain JFK Airport rail link ... Image File history File links Download high-resolution version (831x541, 172 KB) Taken From: english wikipedia File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Linear motor Bombardier Advanced Rapid Transit AirTrain JFK Airport rail link ... Where most trains have a driver’s cab, ART Mark II trains give passengers a large picture window through which they can see where the train is going. ... Charles Wheatstone Sir Charles Wheatstone (February 6, 1802 - October 19, 1875) was the British inventor of many innovations including the English concertina the Stereoscope an early form of microphone the Playfair cipher (named for Lord Playfair, the person who publicized it) He was a major figure in the development of... For other uses, see Kings College. ... 1935 (MCMXXXV) was a common year starting on Tuesday (link will display full calendar). ... Eric Roberts Laithwaite (14 June 1921 – 27 November 1997) was an English engineer, principally known for his development of the linear induction motor and Maglev rail system. ... Royal School of Mines Entrance Imperial College London is a college of the University of London which focuses on science and technology, and is located in South Kensington in London. ... This article is about the capital of England and the United Kingdom. ... The electromagnetic field is a physical field that is produced by electrically charged objects and which affects the behaviour of charged objects in the vicinity of the field. ... As the circular plate moves down through a small region of constant magnetic field directed into the page, eddy currents are induced in the plate. ... For magnetic induction, see Magnetic field. ...

Because of these properties, linear motors are often used in maglev propulsion, as in the Japanese Linimo magnetic levitation train line near Nagoya. However, linear motors have been used independently of magnetic levitation, as in Bombardier's Advanced Rapid Transit systems worldwide and a number of modern Japanese subways, including Tokyo's Toei Oedo Line. This article is about magnetic levitation. ... Linimo train approaching Banpaku Kinen Koen, towards Fujigaoka Station Linimo ), formally the Aichi High-Speed Transit Tobu Kyuryo Line ) is a magnetic levitation train line in Aichi, Japan, near the city of Nagoya. ... Transrapid at the Emsland test facility Transrapid maglev in Shanghai Magnetic levitation transport, or maglev, is a radically new form of transportation that suspends, guides and propels vehicles via electro-magnetic energy. ... Nagoya ) is the fourth largest city in Japan. ... For other uses, see Bombardier (disambiguation). ... Where most trains have a driver’s cab, ART Mark II trains give passengers a large picture window through which they can see where the train is going. ... For other uses, see Tokyo (disambiguation). ... The Toei Ōedo Line (都営地下鉄大江戸線, Toei Chikatetsu Ōedo-sen) is a subway line in Tokyo, Japan operated by the Tokyo Metropolitan Bureau of Transportation (not the Tokyo Metro). ...

Similar technology is also used in some roller coasters with modifications, but at present is still impractical on street running trams, although this in theory could be done by burying it in a slotted conduit. A typical roller coaster The roller coaster is a popular amusement ride developed for amusement parks and modern theme parks. ... This article refers to public transport vehicles running on rails. ...

Outside of public transportation, vertical linear motors have been proposed as lifting mechanisms in deep mines, and the use of linear motors is growing in motion control applications. They are also often used on sliding doors, such as those of low floor trams such as the Citadis and the Eurotram. Dual axis linear motors also exist. These specialized devices have been used to provide direct X-Y motion for precision laser cutting of cloth and sheet metal, automated drafting, and cable forming.Mostly used linear motors are LIM (Linear Induction Motor), LSM (linear Synchronous Motor). Linear DC motors are not used as it includes more cost and Linear SRM suffers from poor thrust. So for long run in traction LIM mostly preferred and for short run LSM mostly preferred. Chuquicamata, the second largest open pit copper mine in the world, Chile. ... Motion control is a sub-field of automation, in which the position and/or velocity of machines are controlled using some type of device such as a hydraulic pump, linear actuator, or an electric motor, generally a servo. ... Passenger door of a low-floor tram Passenger door of a non-low-floor tram In public transportation, low floor is a term describing vehicles such as busses, trolleybusses and trams whose passenger compartment has a floor which is considerably lower than that of traditional cars. ... This article refers to public transport vehicles running on rails. ... A Citadis 202 tram in Melbourne, Australia The Citadis is a low-floor tram built by Alstom in La Rochelle, France, and Barcelona, Spain. ... The modernist Eurotram was first used in Strasbourg. ... Technical drawing, also known as drafting, is the practice of creating accurate representations of objects for technical, architectural and engineering needs. ...

From concept to industrial use

In the 1980s British linear motor manufacturer Linear Drives (now Copley Motion Systems) designed the first tubular linear motor by enclosing the permanent magnets in a sealed stainless steel cylinder. The patented permanent magnet arrangement induces a sinusoidal response in the coils that are enclosed in a square profile body. This allowed machine builders to use the new linear motors with standard sinusoidal servo drives commonly used in motion control.

Tubular Linear Motors

Tubular linear motors are more rugged than early flat bed and u-channel linear motors allowing them to be used in dirty industrial environments such as food packaging and machine tools. The tubular construction protects the permanent magnets from the external environment and automatically balances attractive forces so that the motor is easier to integrate into machines. These motors operate at 5- 9 m/s with high acceleration for dymanamic motion control.

A new type of linear motor, called the ServoTube (see Eureka March 2005) has allowed linear motors to be used in industrial environments by integrating the position sensing electronics into the motor body (called a forcer).

High acceleration

High-acceleration linear motors have been suggested for a number of uses. They have been considered for use as weapons, since current armor-piercing ammunition tends to consist of small rounds with very high kinetic energy, for which just such motors are suitable. Many amusement park roller coasters now use linear induction motors to propel the train at a high speed, as an alternative to using a lift hill. The United States Navy is also using linear induction motors in the Electromagnetic Aircraft Launch System that will replace traditional steam catapults on future aircraft carriers. They have also been suggested for use in spacecraft propulsion. In this context they are usually called mass drivers. The simplest way to use mass drivers for spacecraft propulsion would be to build a large mass driver that can accelerate cargo up to escape velocity. For other uses, see Weapon (disambiguation). ... An Armour piercing shell is a type of ammunition designed to penetrate armour. ... The cars of a roller coaster reach their maximum kinetic energy when at the bottom of their path. ... Electromagnetic Aircraft Launch System (EMALS) is a system under development by the US Navy to launch aircraft from carriers using magnets instead of steam. ... A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is any method used to change the velocity of spacecraft and artificial satellites. ... A mass driver for lunar launch (artists conception) A mass driver or electromagnetic catapult is a method of spacecraft propulsion that would use a linear motor to accelerate payloads up to high speeds. ... Space Shuttle Atlantis launches on mission STS-71. ...

High-acceleration linear motors are difficult to design for a number of reasons. They require large amounts of energy in very short periods of time. One rocket launcher design (see [3]) calls for 300 GJ for each launch in the space of less than a second. Normal electrical generators are not designed for this kind of load, but short-term electrical energy storage methods can be used. Capacitors are bulky and expensive but can supply large amounts of energy quickly. Homopolar generators can be used to convert the kinetic energy of a flywheel into electric energy very rapidly. High-acceleration linear motors also require very strong magnetic fields; in fact, the magnetic fields are often too strong to permit the use of superconductors. However, with careful design this need not be a major problem. This article is about machines that produce electricity. ... Various types of capacitors A capacitor is a device that stores energy in the electric field created between a pair of conductors on which equal but opposite electric charges have been placed. ... A homopolar generator, also known as a unipolar generator, acyclic generator, or disk dynamo, is an electrical generator in which the magnetic field has the same polarity at every point, so that the armature passes through the magnetic field lines of force continually in the same direction. ... Spoked flywheel Flywheel from stationary engine. ... A magnet levitating above a high-temperature superconductor, cooled with liquid nitrogen. ...

Two different basic designs have been invented for high-acceleration linear motors: railguns and coilguns. A railgun is a form of gun that converts electrical energy (rather than the more conventional chemical energy from an explosive propellant) into projectile kinetic energy. ... A coilgun (not to be confused with a railgun) is a type of cannon which uses one or more electromagnetic coils to accelerate a magnetic projectile to high velocity. ...

Rapid transits using linear motor propulsion

The following rapid transits use linear motor propulsion. “Mass Transit” redirects here. ...

• Scarborough RT line (Toronto, Canada, 1985)
• SkyTrain (Vancouver, Canada, 1986)
• Limtrain (Saitama, Japan, 1988 - short-lived demonstration track)
• Nagahori Tsurumi-ryokuchi Line (Osaka, Japan, 1990)
• Toei Ōedo Line (Tokyo, Japan, 1991)
• Kaigan Line (Kobe, Japan, 2001)
• AirTrain JFK (New York, USA, 2003)
• Nanakuma Line (Fukuoka, Japan, 2005)
• Guangzhou Metro Line 4 (Guangdong Province, China, 2005)
• Imazatosuji Line (Osaka, Japan, 2006)
• Green Line (Yokohama, Japan, Under construction)
• Tōzai Line (Sendai, Japan, Under construction)

The Scarborough RT or SRT is an ICTS (Intermediate Capacity Transit System) light rail public transit system in Toronto, Ontario, Canada that uses linear induction technology. ... The SkyTrain is a two-line urban mass transit system in Greater Vancouver, British Columbia, Canada. ... For other uses, see Vancouver (disambiguation). ... Saitama (Japanese: さいたま市; -shi) is the capital city of Saitama Prefecture in Japan. ... a train of the Nagahori Tsurumi-ryokuchi Line The Nagahori Tsurumi-ryokuchi Line ) is one of the lines of Osaka Municipal Subway ), the underground rapid transit system in Osaka City, Japan. ... Osaka )   is a city in Japan, located at the mouth of the Yodo River on Osaka Bay, in the Kansai region of the main island of HonshÅ«. The city is the capital of Osaka Prefecture. ... ÅŒedo Line 12-000 trainset The Toei ÅŒedo Line ) is a subway line in Tokyo, Japan operated by the Tokyo Metropolitan Bureau of Transportation. ... For other uses, see Tokyo (disambiguation). ... The Kaigan Line (海岸線, Kaigan-sen) is one of two lines of Kobe Municipal Subway (7. ... This article is about the Japanese city. ... AirTrain JFK is a 13 km (8. ... New York, New York and NYC redirect here. ... Hashimoto Classification Yard with Type 3000 trainsets. ... This article is about a city in Fukuoka Prefecture, Japan. ... The Guangzhou Metro (廣州地鐵 GuÇŽngzhōu dìtiÄ›) is a metro system in the city of Guangzhou in Guangdong Province of the Peoples Republic of China. ... Not to be confused with the former Kwantung Leased Territory in north-eastern China. ... The Imazatosuji Line ) is one of the lines of Osaka Municipal Subway ), the underground rapid transit system in Osaka City, Japan. ... Osaka )   is a city in Japan, located at the mouth of the Yodo River on Osaka Bay, in the Kansai region of the main island of HonshÅ«. The city is the capital of Osaka Prefecture. ... A train makes a trial run on the Green Line. ... For the town of Yokohama in Aomori Prefecture, see Yokohama, Aomori. ... This April 2007 does not cite its references or sources. ...

See also

• California Screamin' Roller coaster LIM application
• Tomorrowland Transit Authority Slow ride LIM application
• Maverick Another roller coaster LSM application
• SkyTrain (Vancouver, BC, Canada) Rapid transit system
• Brushless wound-rotor doubly-fed electric machine
• capacitor
• coilgun
• compulsator
• flywheel
• homopolar generator
• linear actuator
• pulse transformer
• railgun
• Tether cable catapult system
• Skytran A futuristic Maglev personal rapid transit solution using LIM for forward propulsion.

v • d • e Electric motors
Broad Motor Categories	Synchronous motor • AC motor • DC Motor
Conventional Electric Motors	Induction • Brushed DC • Brushless DC • Stepper • Linear • Unipolar • Reluctance
Novel Electric Motors	Ball bearing • Homopolar • Piezoelectric • Ultrasonic • Electrostatic
Motor Controllers	Adjustable-speed drive • Direct Torque Control • Direct on line starter • Electronic speed control • Variable-frequency drive
See also	Barlow's Wheel • Nanomotor • Traction motor • Lynch motor • Mendocino motor • Repulsion motor • Inchworm motor • Booster (electric power) • Brush (electric)

California Screamin is a steel rollercoaster at Disneys California Adventure theme park. ... TTA logo The Tomorrowland Transit Authority (also called the Blue Line) is a people mover system in Tomorrowland, in the Magic Kingdom in the Walt Disney World Resort near Orlando, Florida. ... Maverick is a linear synchronous motor-launched steel complete-circuit roller coaster at Cedar Point in Sandusky, Ohio. ... The SkyTrain is a two-line urban mass transit system in Greater Vancouver, British Columbia, Canada. ... The Brushless wound-rotor [synchronous] doubly-fed electric machine (i. ... See Capacitor (component) for a discussion of specific types. ... A coilgun (not to be confused with a railgun) is a type of cannon which uses one or more electromagnetic coils to accelerate a magnetic projectile to high velocity. ... A compulsator is the short name for a compensated pulsed alternator, a form of power supply. ... Spoked flywheel Flywheel from stationary engine. ... A homopolar generator, also known as a unipolar generator, acyclic generator, or disk dynamo, is an electrical generator in which the magnetic field has the same polarity at every point, so that the armature passes through the magnetic field lines of force continually in the same direction. ... A linear actuator is a device that develops force and motion linearly. ... A railgun is a form of gun that converts electrical energy (rather than the more conventional chemical energy from an explosive propellant) into projectile kinetic energy. ... Artists conception of satellite with a tether Tether propulsion uses long, strong strings (known as tethers) to change the orbits of spacecraft. ... For the use of unimodal in mathematics and statistics, see Unimodal function Unimodal or SkyTran is a proposal by Douglas Malewicki for a 160km/h (100mph) personal rapid transit system. ... Electric motors of various sizes. ... A synchronous electric motor is distinguished by its rotor spinning at the same rate as the oscillating field which drives it. ... Rotating magnetic field as a sum of magnetic vectors from 3 phase coils An electric motor converts electrical energy into mechanical energy. ... Electric motors of various sizes. ... Image File history File links Download high resolution version (707x768, 49 KB) Summary Largest motor: 1 Hp (750 W) Next largest: 25 W Small motors: CD player motor, toy motor, CD drive head traverse motor Licensing I, the creator of this work, hereby grant the permission to copy, distribute and... Induction Motor (IM) is one kind of AC motor where power is supplied to the rotating device by induction. ... A brushed DC motor is a type of electric motor that, in contrast to a brushless DC motor, has two static electric contacts (brushes) that come in contact with different sections of a split disc (commutator) at different times, spinning the motor through electromagnets. ... A brushless DC motor (BLDC) is an AC synchronous electric motor that from a modeling perspective looks very similar to a DC motor. ... The top electromagnet (1) is charged, attracting the topmost four teeth of a sprocket. ... There are very few or no other articles that link to this one. ... A reluctance motor is a type of synchronous electric motor which uses the phenomenon of reluctance to induce non-permanent magnetic poles on the rotor. ... A ball bearing motor is an unusual electric motor that is constructed as follows: Take a short hollow copper pipe and fit 2 ball bearings on either end. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A piezoelectric motor or piezo motor is a type of electric motor based upon the change in shape of a piezoelectric material when an electric field is applied. ... The electronic (gold-plated) contacts of an EF mount lens. ... An electrostatic motor or capacitor motor is a type of electric motor based on the attraction and repulsion of electric charge. ... A motor controller is a device or group of devices that serves to govern in some predetermined manner the performance of an electric motor. ... Adjustable speed drive (ASD) is one of the most general terms applied to equipment used to control the speed of machinery. ... Direct torque control is one method used in variable frequency drives to control the torque (and thus finally the speed) of the three-phase AC electric motors. ... A direct on line starter is often abbreviated DOL starter and is a widely-used starting method of electric motors. ... An electronic speed control or ESC is a device mounted onboard an electrically-powered R/C model in order to vary its drive motors speed, its direction and even to act as a dynamic brake in certain controllers. ... Small Variable Frequency Drive (VFD) A variable-frequency drive (VFD) is a system for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor. ... Barlows Wheel is the name given to an early demonstration of an electric motor, designed and built by English mathematician and physicist, Peter Barlow in 1822. ... A nanomotor is a molecular device capable of converting energy into movement and forces on the order of the pico-newtons. ... Traction motor typically refers to those motors that are used to power the driving wheels of a railroad locomotive, electrical multi-unit train (such as a subway or light rail vehicle train), or a tram. ... The Lynch Motor is a unique axial gap permanent magnet brushed DC motor invented by Cedric Lynch, U.S. patent 4823039. ... The Mendocino motor is a solar powered magnetically levitated motor. ... A Repulsion motor is a type of electric motor for use on alternating current. ... The inchworm motor is a device using piezoelectric actuators to move a shaft with nanometer precision. ... A Booster was a motor-generator (MG) set used for voltage regulation in direct current (DC) electrical power circuits. ... A pair of carbon brushes In electrical engineering, brushes conduct current between stationary wires and moving parts, most commonly in a rotating shaft. ...

External links

• Electromagnetic Guns - A page describing recent research at MIT.
• MagneMotion Home page Linear Synchronous Motor manufacturer, white papers and applications.
• Malev
• Piezoelectric Linear Motors