Washing machine


A washing machine is a machine designed to assist in the cleaning of
laundry, i.e. clothing and other household textile such as towels and
sheets. It is generally restricted to machines that use water as the primary
cleaning solution, as distinct from dry cleaning which uses alternative
cleaning fluids and is generally performed by specialist businesses.

Mechanical washing machines have been available since at least the 19th
century, and their basic principles of operation have remained largely
unchanged. Their first purpose is to suspend the material to be cleaned in
water contaning detergent. The clothes and water are then "agitated" - moved
back and forth in a chaotic manner. The water is then pumped out and the
clothes partially dried by spinning them rapidly in a low-speed centrifuge.
Clean water is then added and the clothes and water agitated to remove any
remaining traces of the detergent. Finally, the clothes are (usually) spun
again (though some clothes are removed immediately and dried by alternative
means without further spinning).

Virtually all contemporary washing machines are powered by electricity,
though hand-powered or even steam-powered machines were common in earlier
times. They are almost universal in wealthier countries, though some people
living in smaller apartments do not have room for them and use communal
launderettes.

Contemporary washing machines are available in two main configurations -
"top loading" and "front loading". The "top loading" design, the most
popular in the United States and parts of Europe , places the clothes in a
vertically-mounted cylinder, with a propeller-like agitator in the center of
the bottom of the cylinder. Clothes are loaded at the top of the machine,
which is covered with a hinged door. The "front loading" design most popular
in the UK instead mounts the cylinder horizontally, with loading through a
glass door at the front of the machine. Agitation is supplied by the actual
back-and-forth rotation of the cylinder. The cylinder is also called the drum.

Tests comparing front-loading and top-loading machines empirically have
shown that, in general, front-loaders wash clothes more thoroughly, cause
less wear, and use less water and energy than top-loaders. They also allow a
dryer to be mounted directly above the washer, impossible with a top-loader.
Top-loaders do have the advantages that they complete washing much faster,
tend to cost less for the same capacity machine, and allow clothes to be
removed at intermediate stages of the cycle (for instance, if some clothes
within a wash are not to be spun.

In the late 1990s, the British inventor James Dyson launched a type of
washing machine with two cylinders rotating in opposite directions; which,
it is claimed, reduces the wash time and produces cleaner results.

Washing /Drying machine

The single appliance can perform both washing and drying functions to cut
out the process of loading and unloading clothes from one machine to another.

Some time ago, the problem with such machines was that only half of the
laundry can be dried after the washing process is complete. Nowadys, some
washing/driers are capable of performing both functions in a single machine
without interruption and with the full laundry load.