Saturday, March 31, 2012

Lighter



A lighter is a portable device used to generate a flame. It consists of a metal or plastic container filled with a flammable fluid or pressurized liquid gas, a means of ignition, and some provision for extinguishing the flame.

History

The first lighters were invented in the 16th century and were converted flintlock pistols that used gunpowder. One of the first lighters was invented by the German chemist named Johann Wolfgang Döbereiner in 1823 and was often called Döbereiner's lamp.[1] This lighter worked by a reaction of hydrogen to platinum sponge, which gave off a great amount of heat. The device was very large and highly dangerous and fell out of production by the end of the 19th century.[1]
The patenting of ferrocerium (often misidentified as flint) by Carl Auer von Welsbach in 1903 has made modern lighters possible. When scratched, it produces a large spark which is responsible for lighting the fuel of many lighters, and is suitably inexpensive for use in disposable items.
Using Carl Auer von Welsbach's flint, companies like Ronson were able to develop practical and easy to use lighters. In 1910 Ronson released the first Pist-O-Liter and in 1913 the company developed its first lighter, called the "Wonderlite", which was a permanent match style of lighter.[2]
The Zippo lighter and company were invented and founded by George G. Blaisdell in 1932. The Zippo was noted for its reliability, "Life Time Warranty" and marketing as "Wind-Proof".[3] Most early Zippos used naphtha as a fuel source.
In the 1950s there was a switch in fuel choice from naphtha to butane, as butane allows for a controllable flame and has less odour.[4] This also led to the use of piezoelectric spark, which replaced the need for a flint wheel in some lighters and was used in many Ronson lighters.

Operation

Naphtha (very similar to gasoline) based lighters employ a saturated cloth wick and fibre packing to absorb the fluid and prevent it from leaking. They employ an enclosed top to prevent the volatile liquid from evaporating, and to conveniently extinguish the flame. Butane lighters have a valved orifice that meters the butane gas as it escapes.
A spark is created by striking metal against a flint, or by pressing a button that compresses a piezoelectric crystal (piezo ignition), generating an electric arc. In naphtha lighters, the liquid is sufficiently volatile, and flammable vapour is present as soon as the top of the lighter is opened. Butane lighters combine the striking action with the opening of the valve to release gas. The spark ignites the flammable gas causing a flame to come out of the lighter which continues until either the top is closed (naphtha type), or the valve is released (butane type).
A metal enclosure with air holes generally surrounds the flame, and is designed to allow mixing of fuel and air while making the lighter less sensitive to wind. The high energy jet in butane lighters allows mixing to be accomplished by using Bernoulli's principle, so that the air hole(s) in this type tend to be much smaller and farther from the flame.
Specialized "windproof" butane lighters are manufactured for demanding conditions such as shipboard, high altitude, and wet climates. Some dedicated models double as synthetic rope cutters. Such lighters are often far hotter than normal lighters (those that use a "soft flame") and can burn in excess of 1100 °C. Contrary to common misconception, the windproof capabilities are not achieved from "higher pressure" fuel. Windproof lighters use the same fuel (butane) as standard lighters, and therefore develop the same vapour pressure. The difference is that windproof lighters mix the fuel with air, and may also pass the butane/air mixture through a catalytic coil. An electric spark starts the initial flame, and soon after the coil is hot enough to sustain a catalytic reaction and cause the fuel/air mixture to burn on contact. In essence, the flame is constantly reignited by the coil.

Other types

Permanent match

A typical form of lighter is the everlasting match, consisting of a naphtha fuel-filled metal shell and a separate threaded metal rod assembly —the "match"— serving as the striker and wick. This "metal match" is stored screwed into the fuel storage compartment, the shell. (see photo)
The fuel-saturated striker/wick assembly is unscrewed to remove, and scratched against a flint on the side of the case to create a spark. Its concealed wick catches fire, resembling a match. The flame is extinguished by screwing the "match" back into the shell, where it absorbs fuel for the next use. An advantage over other naphtha lighters is that the fuel compartment is sealed shut with a rubber o-ring, which slows or stops fuel evaporation.

Flame-less lighter

A flame-less lighter is the safe alternative to traditional lighters. The flameless lighter uses an enclosed heating element, thus, the device does not emit an open flame. Typical flameless heating elements are an electrically heated wire or an artificial coal.
Flameless lighters are designed for use in any environment where an open flame must not exist or where conventional lighters or matches are not permitted.
Many advertised so-called flameless lighters are not flameless at all, but the flame is invisible. If a piece of paper can be easily ignited, it is probably not a true flameless lighter, and certainly not safe in explosive environments and so forth.

Automobile lighter

Some automobiles are equipped with an electric lighter housed in a 12 V receptacle. Its electric heating element becomes hot in seconds upon activation. The car lighter was claimed to have been invented by Alexander Kucala, a tavern owner/ inventor, on the south side of Chicago in the early 1920's called the AL Lighter.

Safety

Two technical standards relate to the safety of lighters: the International Standard EN ISO 9994:2002[5] and the European standard EN 13869:2002.[6]
The International Standard establishes non-functional specifications on quality, reliability and safety of lighters and appropriate test procedures. For instance, a lighter should generate flame only through positive action on the part of the user, two or more independent actions by the user, or an actuating force greater than or equal to 15 N. The standard also specifies other safety features, such as the lighter's maximum flame height and its resistance to elevated temperatures, dropping, and damages from continuous burning. However, the standard does not include child resistance specifications.
The European standard EN 13869:2002[6] establishes child-resistance specifications and defines as novelty lighters those that resemble another object commonly recognized as appealing to children younger than 51 months, or those that have entertaining audio or animated effects.
As matches, lighters, and other heat sources are the leading causes of fire deaths for children,[7] many jurisdictions, such as the EU,[8] have forbidden the marketing of novelty or non-child resistant lighters. Examples of child resistance features, include the use of a smooth or shielded spark wheel. Many people remove the child proofing from lighters by prying off the metal with scissors or keys, making the lighter easier to ignite.
In 2005 the fourth edition of the ISO standard was released (ISO9994:2005). The main change to the 2004 Standard is the inclusion of specifications on safety symbols.




 



No comments:

Post a Comment