A lighter is a
portable device used to create a flame. It consists of a metal
or plastic container filled with lighter fluid (usually naptha
or liquid butane under pressure), as well as a means of ignition
and some provision for extinguishing the flame, by depriving it
of either air or fuel. Below -0.5 C the pressure in a Butane
lighter disappears.
Lighters using naptha have a wick which is immersed in the fluid
and becomes saturated. This type usually has a fiber packing
material which absorbs the liquid to keep it from leaking. They
also must have 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 as
it escapes as a gas.
A spark is created by striking metal against a flint, or by
pressing a button that compresses a piezoelectric crystal,
generating a voltaic arc (see Piezo ignition). In naphtha
lighters the liquid is volatile enough that flammable gas 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. In a plastic butane lighter
this metal enclosure also regulates the distance from the valve
to the beginning of the flame. If the flame is too close to the
valve, there is a risk of the flame melting some, most, or all
of the plastic components of the lighter which are in close
proximity to the valve.
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Match
History of
the term match
History of the modern match
Friction matches
Special purpose matches
Matchbooks
Fires due to
lit matches
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