This article is about the engine component. For other uses of the term, see Magneto (disambiguation). Image File history File links No higher resolution available. ... For other uses, see Engine (disambiguation). ...

A magneto is a device used in the ignition system of gasoline-powered internal combustion engines to provide pulses of high tension current to the spark plugs. Once found in every gasoline-powered automobile, it is now confined mainly to lawnmowers, chainsaws, and internal-combustion aviation engines. It should be noted that magnetos and coils used in early internal-combustion engines used the term "tension" in lieu of the more modern term "voltage." The term "high tension" is equivalent to "high voltage." The ignition system of an internal-combustion engine is an important part of the overall engine system that provides for the timely burning of the fuel mixture within the engine. ... A colorized automobile engine The internal combustion engine is an engine in which the combustion of fuel and an oxidizer (typically air) occurs in a confined space called a combustion chamber. ... This article or section should include material from Spark gap A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed aerosol gasoline by means of an electric spark. ... A lawn mower (often spelled as one word—lawnmower) is a machine (electric or mechnical) used to cut grass to an even length. ... For other uses, see Chainsaw (disambiguation). ... Aviation encompasses all the activities relating to airborne devices created by human ingenuity, generally known as aircraft. ...

History

The first person to develop the idea of a high-tension magneto was Andre Boudeville, but his design omitted a condenser (capacitor); Frederick Simms in partnership with Robert Bosch were the first to develop a practicable high-tension magneto. ^[1] See Capacitor (component) for a discussion of specific types. ... Daimler has been since 1896 the marque of motor car of the British Daimler Motor Company based in Coventry. ... Robert Bosch at the age of 27 Robert Bosch (September 23, 1861 - March 12, 1942), German industrialist and philanthropist, born in Albeck near Ulm as the 11th child of Servatius and Margarete Bosch, themselves children of wealthy farmers. ...

The magneto was introduced on the 1899 Daimler Phönix. This was followed by Benz, Mors, Turcat-Mery, and Nesseldorf,^[2] and soon were used on most cars up until about 1918 in both low voltage (voltage for secondary coils to fire the spark plugs) and high voltage magnetos (to fire the spark plug directly, similar to coil ignitions, introduced by Bosch in 1903).^[2] Daimler-Motoren-Gesellschaft (Daimler Motor Company or DMG) was a German engine and later automobile manufacturer that operated from 1890 until 1926. ... Daimler-Motoren-Gesellschaft (Daimler Motor Company or DMG) was a German engine and later automobile manufacturer that operated from 1890 until 1926. ... Benz can refer to: Karl Benz, a German automobile engineer and inventor Mercedes-Benz, a brand of automobiles and trucks Kafi Benz, an American writer, historian, designer, and artist, the founder of Friends of Seagate Inc. ... In Roman mythology, Mors is the personification of death. ... An induction coil or spark coil (archaically known as a Ruhmkorff coil) is a type of disruptive discharge coil. ...

Operation

In the type known as a shuttle magneto, the engine rotates a coil of wire between the poles of a magnet. In the inductor magneto, the magnet is rotated and the coil remains stationary. For other uses, see Magnet (disambiguation). ... For other uses, see Magnet (disambiguation). ...

On each revolution, a cam opens the contact breaker one or more times, interrupting the current, which causes the electromagnetic field in the primary coil to collapse. As the field collapses there is a voltage induced (as described by Faraday's Law) across the primary coil. As the points open, point spacing is such that the voltage across the primary coil will arc across the points. A capacitor is placed across the points to suppress the arc, set the amount of voltage across the primary coil, and to control the rate at which the electrical energy dissipates in the primary coil. For other uses, see CAM. Animation showing rotating cams and cam followers producing reciprocating motion. ... In electricity, current refers to electric current, which is the flow of electric charge. ... 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. ... Faradays law can mean: Faradays law of induction (electromagnetic fields) Faradays law of electrolysis Category: ...

A second coil, with many more turns than the primary, is wound on the same The ratio of the number turns in the secondary winding to the number of turns in the primary winding, called the turns ratio,. When the voltage is distributed and dissipates across the primary coil, a proportional voltage is induced across the secondary winding of the coil. The turns ratio between the primary and secondary coil is selected so that the voltage across the secondary reaches a very high value, enough to arc across the gap of the spark plug.

Aviation

Because it requires no battery or other source of energy, the magneto is a compact and reliable self-contained ignition system which is why it is still in use in some aviation applications. Magneto-equipped aircraft engines are typically dual-plugged, that is, each cylinder has two spark plugs, with each plug having its own separate magneto. This arrangement provides redundancy in the event of a failure of one of the magnetos. Two sparks provide for a more complete and efficient burn of the fuel mixture, and if placed far apart in the combustion chamber, decreases burn time, allowing higher engine speeds. For this reason, double-plugging is also used in high-performance automobiles and motorcycles. A battery is of one or more electrochemical cells, which store chemical energy and make it available in an electrical form. ...

1896 Telephone, hand crank on right (Sweden)

Image File history File links 1896_telephone. ... Image File history File links 1896_telephone. ...

Telephone

Many early manual telephones had a "Magneto" or hand cranked generator to produce a (relatively) high voltage alternating signal to ring the bells of other telephones on the same (party) line and to alert the operator. These were usually on long rural lines served by small manual exchanges which were not "common battery". The telephone instrument was "local battery", containing two large "No 6" dry cells. For other uses, see Telephone (disambiguation). ...

See also

• Ignition system

The ignition system of an internal-combustion engine is an important part of the overall engine system that provides for the timely burning of the fuel mixture within the engine. ...

Notes

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