spark plug

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spark plug:

see ignitionignition,
apparatus for igniting a combustible mixture. The German engineer Nikolaus A. Otto, in his first gas engine, used flame ignition; another method was heating a metal tube to incandescence.
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The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Spark Plug


a device used to ignite the air-fuel mixture in the cylinders of internal-combustion engines equipped with carburetors. The mixture is ignited by a spark passing between the spark plug’s electrodes. Spark plugs are threaded into the engine’s cylinder head and consist of a steel shell with a side electrode and an insulator with a center electrode. A terminal is mounted on the top part of the center electrode. A high voltage is applied periodically across the gap between the center electrode and the side electrode, causing a spark to jump across the gap. The length of the skirt of the insulator determines the thermal characteristic of the spark plug. A short skirt provides a high heat transfer from the insulator to the shell. Spark plugs with short skirts are called cold plugs; those with long skirts are called hot plugs. Cold plugs are used for continuous engine operation under heavy loads or at elevated temperatures. [23–208–]

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

spark plug

[′spärk ‚pləg]
A device that screws into the cylinder of an internal combustion engine to provide a pair of electrodes between which an electrical discharge is passed to ignite the explosive mixture.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Spark plug

A device that screws into the combustion chamber of an internal combustion engine to provide a pair of electrodes between which an electrical discharge is passed to ignite the combustible mixture. The spark plug consists of an outer steel shell that is electrically grounded to the engine and a ceramic insulator, sealed into the shell, through which a center electrode passes (see illustration). The high-voltage current jumps the gap between the center electrode and the ground electrode fixed to the outer shell.

The electrodes are made of nickel and chrome alloys that resist electrical and chemical corrosion. Some center electrodes have a copper core, while others have a platinum tip. Many spark plugs have a resistor in the center electrode to help prevent radio-frequency interference. The parts exposed to the combustion gases are designed to operate at temperatures hot enough to prevent electrically conducting deposits but cool enough to avoid ignition of the mixture before the spark occurs. See Ignition system

McGraw-Hill Concise Encyclopedia of Engineering. © 2002 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
On the basis of product type, market is divided into cold spark plug and hot spark plug.
Spark Plug has yet to get on the scoresheet this season, but ran a fine race on his penultimate outing when finishing a half-length runner-up to Mustashry in the Listed Gala Stakes at Sandown.
Spark Plug surged gamely towards the finishing line on the Knavesmire -he was beaten under two lengths by the winner -which tends to suggest the extra furlong in the Cambridgeshire will suit him down to the ground.
Scientists in Japan are finding that perovskites have the potential to improve the fabrication of electrodes and wiring in ceramic-based electronics such as spark plugs.
Durant, who was purchasing his spark plugs from Rahway Plugs in New Jersey, promised Champion that if he could make a better spark plug, he'd switch suppliers.
the spark plugs. What's more, lean fuel mixtures and alternative fuels are more difficult to ignite.
You can use the same old tune-up tools (ratchet, spark plug socket and gap gauge).
* Use a spark plug socket wrench to remove the spark plug.
The device uses two, high-current automotive-style coils connected in parallel to the spark plug through a diode block, which ensure that the coils' discharge path is through the spark plug.
That "P" in the spark plug designated "projected tip," putting the flame too close to the piston crown.