Fan (mechanical)

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Fan (mechanical)

A mechanical fan is an electrically

Electricity

Electricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena such as lightning and static electricity, but in addition, less familiar concepts such as the electromagnetic field and electromagnetic induction....
powered device

Device

Device may refer to:...
used to produce an airflow for the purpose of creature comfort (particularly in the heat), ventilation

Ventilation (architecture)

Ventilation is the intentional movement of air from outside a building to the inside. It is the V in HVAC. With clothes dryers, and combustion equipment such as water heaters, boilers, fireplaces, and wood stoves, their exhausts are often called vents or flues — this should not be confused with ventilation....
, exhaust, or any other gaseous transport.

Mechanically, a fan can be any revolving vane or vanes used for producing currents of air

Current (fluid)

File:Water patterns.JPGA current, in a river or stream, is the flow of water influenced by gravity as the water moves downhill to reduce its potential energy....
.

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Encyclopedia

A mechanical fan is an electrically

Electricity

Device

Device may refer to:...
used to produce an airflow for the purpose of creature comfort (particularly in the heat), ventilation

Ventilation (architecture)

Current (fluid)

File:Water patterns.JPGA current, in a river or stream, is the flow of water influenced by gravity as the water moves downhill to reduce its potential energy....
. Fans produce air flows with high volume and low pressure, as opposed to a gas compressor

Gas compressor

A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe ....
which produces high pressures at a comparatively low volume. A fan blade will often rotate when exposed to an air stream, and devices that take advantage of this, such as anemometer

Anemometer

An anemometer is a device that is used for measuring wind speed, and is one instrument used in a weather station. The term is derived from the Greek word anemos, meaning wind....
s and wind turbine

Wind turbine

A wind turbine is a rotating machine which converts the kinetic energy in wind into mechanical energy. If the mechanical energy is used directly by machinery, such as a pump or grinding stones, the machine is usually called a windmill....
s often have designs similar to that of a fan.

Typical applications include climate control, cooling systems, personal comfort (e.g., an electric table fan), ventilation (e.g., an exhaust fan), winnowing (e.g., separating chaff of cereal

Cereal

Cereals, or cereal grains, are mostly Poaceae cultivated for their edible brans or fruit seeds . Cereal grains are grown in greater quantities and provide more energy worldwide than any other type of crop; they are therefore staple foods....
grains), removing dust (e.g. sucking as in a vacuum cleaner

Vacuum cleaner

A vacuum cleaner is a device that uses an air pump to create a partial vacuum to suck up dust and dirt, usually from floors.Most homes with carpeted floors in developed countries possess a vacuum cleaner for cleaning....
), drying (usually in addition to heat) and to provide draft for a fire

Fire

Fire is the oxidation of a combustion material releasing heat, light, and various Chemical reaction products such as carbon dioxide and water....
. It is also common to use electric fans as air fresheners, by attaching fabric softener

Fabric softener

Fabric Softener is used to prevent static cling and make fabric softer. It is available as a liquid or as dryer sheets. Popular brand names include Downy , Snuggle, Bounce , Comfort and Sta-Soft....
sheets to the protective housing. This causes the fragrance to be carried into the surrounding air.

In addition to their utilitarian function, vintage or antique fans, and in particular electric fans manufactured from the late 19th century through the 1950s, have become a recognized collectible

Collectible

A collectable or collectible is typically a manufactured item designed for people to collect. In this respect, they are distinguishable from other subjects of collections, which may also include natural objects and objects manufactured for purposes other than collecting ....
category, and in the U.S.A. an active collector club, the Antique Fan Collectors Association, supports the hobby..

History

The first recorded mechanical fan was the punkah fan used in the Middle East

Middle East

File:GreaterMiddleEast1.pngThe Middle East is a region that spans southwestern Asia, western Asia, and northeastern Africa. It has no clear boundaries, often used as a synonym to Near East, in opposition to Far East....
in the early 19th century. It had a canvas covered frame that was suspended from the ceiling. Servants, known as punkah wallahs, pulled a rope

Rope

A rope is a length of fibers, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength ....
connected to the frame to move the fan back and forth.

The Industrial Revolution

Industrial Revolution

The Industrial Revolution was a period in the late 18th and early 19th centuries when major changes in agriculture, manufacturing, production, and transportation had a profound effect on the socioeconomics and cultural conditions in United Kingdom....
in the late 19th century introduced belt-driven fans powered by factory waterwheels. Attaching wooden or metal blades to shafts overhead that were used to drive the machinery, the first industrial fans were developed. One of the first workable mechanical fans was built by Alexander Sablukov

Alexander Sablukov

Alexander Alexandrovich Sablukov was a Russian Lieutenant General, engineer and inventor. In 1832 Sablukov is credited with invention of the centrifugal fan , later developed a type of water pumps....
in 1832. He called his invention, a kind of a centrifugal fan, an Air Pump. Centrifugal fans were successfully tested inside coal mines and factories in 1832-1834. When Thomas Edison

Thomas Edison

Thomas Alva Edison was an American inventor and businessman who developed many devices that greatly influenced life around the world, including the phonograph and the long-lasting, practical electric light bulb....
and Nikola Tesla

Nikola Tesla

Nikola Tesla was an inventor and a mechanical engineer and electrical engineer. Tesla was born in the village of Smiljan near the town of Gospic, in Croatia ....
introduced electrical power in the late 19th and early 20th centuries for the public, the personal electrical fan was introduced. Between 1882 and 1886, Dr. Schuyler Skaats Wheeler

Schuyler Wheeler

Schuyler Skaats Wheeler was an United States engineer who invented the two-blade electric fan in 1882 at age 22.Wheeler was born in Massachusetts....
developed the two-bladed desk fan, a type of personal electric fan. It was commercially marketed by the American firm Crocker & Curtis electric motor company. In 1882, Philip Diehl

Philip Diehl (inventor)

Philip H. Diehl was a Germany-United States engineer and inventor who held several U.S. patents, including light bulbs, electric motors for sewing machines and other uses, and ceiling fans....
introduced the electric ceiling fan. Diehl is considered the father of the modern electric fan. In the late 19th century, electric fans were used only in commercial establishments or in well-to-do households. Heat-convection fans fueled by alcohol, oil, or kerosene were common around the turn of the 20th century.

The first American fans were made from around the late 1890s to the early 1920s. They had brass

Brass

Brass is any alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. In comparison, bronze is principally an alloy of copper and tin....
blades, a lot of them also had brass cages, and though they were built very well internally, they were far from finger safe, as a lot of them had cage openings so big that one could put an entire hand or arm right through it. Many children had hands and fingers severely injured by those fans.

In the 1920s, industrial advances allowed steel to be mass-produced in different shapes, bringing fan prices down and allowing more homeowners to afford them. In the 1930s, the first art deco fan (the "Swan Fan") was designed. In the 1950s, fans were manufactured in colors that were bright and eye catching. Central air conditioning

Air conditioning

An air conditioner is an appliance, system, or Mechanism designed to extract heat from an area via a refrigeration cycle. In construction, a complete system of heating, Ventilation , and air conditioning is referred to as "HVAC." Its purpose, in a building or an automobile, is to provide comfort during either hot or cold...
in the 1960s brought an end to the golden age of the electric fan. In the 1970s, Victorian-style ceiling fans became popular.

In the 20th century, fans have become utilitarian. During the 2000s, fan aesthetics have become a concern to fan buyers. The fan is part of everyday life in the Far East

Far East

The Far East is a term current in English language to refer to the countries of East Asia. The term is often expanded to also include Southeast Asia and South Asia, for economic and cultural reasons, for example because Buddhism is common to East Asia, Southeast Asia and South Asia....
, Japan, and Spain

Spain

Spain or the Kingdom of Spain , is a country located in Southern Europe on the Iberian Peninsula.The Spanish constitution does not establish any official denomination of the country, even though Espa?a , Estado espa?ol and Naci?n espa?ola are used interchangeably....
(among other places). Electric fans have been largely replaced by air conditioners in offices, but they are still a common household appliance.

Types of fans

Mechanical revolving blade fans are made in a wide range of designs. In a home you can find fans that can be put on the floor or a table, or hung from the ceiling, or are built into a window, wall, roof, chimney, etc. They can be found in electronic systems such as computer

Computer

A computer is a machine that manipulates Data according to a list of Code .The first devices that resemble modern computers date to the mid-20th century , although the computer concept and various machines similar to computers existed earlier....
s where they cool the circuits inside, and in appliances such as hair dryers and space heaters. They are also used for cooling in air-conditioning systems, and in automotive engines, where they are driven by belts or by direct motor. Fans create a wind chill

Wind chill

Wind chill is the Felt air temperature felt on exposed skin due to wind. The degree of this phenomenon depends on both air temperature and wind speed....
but do not lower temperatures directly.

There are three main types of fans used for moving air, axial, centrifugal (also called radial) and cross flow (also called tangential).

Axial fans

The axial-flow fans have blades that force air to move parallel

Parallel (geometry)

Parallelism is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more line s or plane , or a combination of these....
to the shaft about which the blades rotate. Axial fans blow air across the axis of the fan, linearly, hence their name. This type of fan is used in a wide variety of applications, ranging from small cooling fans for electronics to the giant fans used in wind tunnel

Wind tunnel

A wind tunnel is a research tool developed to assist with studying the effects of air moving over or around solid objects.Ways that wind-speed and flow are measured in wind tunnels:...
s.

Examples of axial fans are:

Table fan - Basic elements of a typical table fan include the fan blade, base, armature and lead wire
Wire

A wire is a single, usually cylinder , elongated string of metal. Wires are used to bear mechanical Structural loads and to carry electricity and telecommunications Wiktionary:signal....
s, motor, blade guard, motor housing, oscillator gearbox, and oscillator shaft. The oscillator is a mechanism that motions the fan from side to side. The axle comes out on both ends of the motor, one end of the axle is attached to the blade and the other is attached to the oscillator gearbox. The motor case joins to the gearbox to contain the rotor and stator. The oscillator shaft combines to the weighted base and the gearbox. A motor housing covers the oscillator mechanism. The blade guard joins to the motor case for safety.

Electro-mechanical fans, among collectors, are rated according to their condition, size, age, and number of blades. Four-blade designs are the most common. Five-blade or six-blade designs are rare. The materials from which the components are made, such as brass, are important factors in fan desirability.

*Ceiling fan

Ceiling fan

A ceiling fan is a device suspended from the ceiling of a room, which employs hub-mounted rotating paddles to circulate air in order to produce a cooling or destratification effect....
- A fan suspended from the ceiling of a room is a ceiling fan.

In automobile
Automobile

An automobile or motor car is a wheeled motor vehicle for transportation passengers, which also carries its own car engine or motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally f...
s, a mechanical fan provides engine cooling
Engine cooling

Engine cooling is cooling an engine, typically using either air or liquid....
and prevents the engine from overheating by blowing or sucking air through a coolant
Coolant

A coolant is a fluid which flows through a device in order to prevent its overheating, transferring the heat produced by the device to other devices that utilize or dissipate it....
-filled radiator
Radiator

Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in automobiles, buildings, and electronics....
. It can be driven with a belt and pulley
Pulley

A pulley is a mechanism composed of a wheel with a Groove between two flanges around the wheel's circumference. A rope, cable or belt usually runs inside the groove....
off the engine
Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs in a combustion chamber inside and integral to the engine. In an internal combustion engine it is always the expansion of the high temperature and pressure gases that are produced by the combustion which apply force to the movable component of the engine, such as...
's crankshaft
Crankshaft

The crankshaft, sometimes casually abbreviated to crank , is the part of an engine which translates reciprocation linear piston motion into rotation....
or an electric fan switched on/off by a thermo
Thermostat

A thermostat is a Measuring instrument for regulating the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature....
switch
Switch

In electronics, a switch is an electrical component which can break an electrical circuit, interrupting the Electric current or diverting it from one conductor to another....
.

Computer fan
Computer fan

A computer fan is any fan inside a computer case used for cooling purposes, and may refer to fans that draw cooler air into the case from the outside, expel warm air from inside, or move air across a heatsink to cool a particular component....

Variable Pitch Fan A variable pitch fan is used where precise control of static pressure within supply ducts is required. The fan wheel will spin at a constant RPM (1780 in this case). The blades follow the control pitch hub. As the hub moves toward the rotor the blades increase their angle of attack and an increase in flow results.

Centrifugal fan

Often called a "squirrel cage" (due to its similarity in appearance to exercise wheels

Hamster wheel

Most wheels are constructed of steel or plastic, both with advantages and problems. Solid plastic wheels are safer for some types of pets, such as hamsters, because the space between rungs is solid and the animal's feet or legs cannot get stuck between rungs, a injury risk in steel wheels....
for pet rodents), the centrifugal fan has a moving component (called an impeller) that consists of a central shaft about which a set of blades, or ribs, are positioned. Centrifugal fans blow air at right angles to the intake of the fan, and spin the air outwards to the outlet (by deflection and centrifugal force

Centrifugal force

In classical mechanics, centrifugal force is an outward force associated with rotation. Centrifugal force is one of several so-called pseudo-forces , so named because, unlike Fundamental interaction, they do not originate in interactions with other bodies situated in the environment of the particle upon which they act....
). The impeller rotates, causing air to enter the fan near the shaft and move perpendicular

Perpendicular

In geometry, two line or plane , are considered perpendicular to each other if they form congruence adjacent angles angles . The term may be used as a noun or adjective....
ly from the shaft to the opening in the scroll-shaped fan casing. A centrifugal fan produces more pressure for a given air volume, and is used where this is desirable such as in leaf blower

Leaf blower

A leaf blower is gardening tool that propels air out of a nozzle to move yard debris such as leaves. Leaf blowers are usually powered by two-stroke engine or an electric motor, but four-stroke engines were recently introduced to partially address air pollution concerns....
s, air mattress inflators, inflatable structures and various industrial purposes. They are typically noisier than comparable axial fans.

Cross flow fan

A cross flow fan, is a centrifugal fan in which the air flows through the fan, rather than through an inlet. The rotor of a cross flow fan is covered to create a pressure differential. When used in household fans, cross flow fans have a smaller opening on one side and a larger opening on the other. The resultant pressure difference allows air to flow straight through the fan, even though the fan blades counter the flow of air on one side of the rotation. Cross flow fans give airflow along the entire width of the fan. Cross flow fans are noisier than ordinary centrifugal fans presumedly because the fan blades fight the flow of air on one side of the rotation unlike normal squirrel cage fans. Cross flow fans are often used in air conditioners, automobile ventilation systems, and for cooling in medium-sized equipment such as photocopier

Photocopier

A photocopier is a machine that makes paper copies of documents and other visual images quickly and cheaply. Most current photocopiers use a technology called xerography, a dry process using heat....
s. The action of a fan or blower causes pressures slightly above atmospheric, which are called plenum

Plenum

Plenum may refer to:* Plenum chamber, a chamber intended to contain air, gas, or liquid at positive pressure* Plenism, or Horror vacui * Plenum, a meeting of a deliberative assembly in which all members are present; contrast with quorum...
s.

Fan motor

A stand alone fan is typically powered with an electric motor

Electric motor

An electric motor uses electrical energy to produce mechanical energy, nearly always by the interaction of magnetic fields and current-carrying conductors....
. Fans are often attached directly to the motor's output, with no need for gears or belts. The electric motor is either hidden in the fan's center hub or extends behind it. For big industrial fans, 3-phase asynchronous motors are commonly used, placed near the fan and driving it through a belt and pulleys

Pulley

A pulley is a mechanism composed of a wheel with a Groove between two flanges around the wheel's circumference. A rope, cable or belt usually runs inside the groove....
. Smaller fans are often powered by shaded pole AC motors

Shaded-pole motor

A shaded-pole motor is a type of alternating current single-phase electric power induction electric motor. As in other induction motors the rotating part is a squirrel-cage rotor....
, or brushed

Brushed DC electric motor

A brushed DC motor is an internally Commutator electric motor designed to be run from a DC power source....
or brushless DC motors

Brushless DC electric motor

A brushless DC motor is a synchronous electric motor which is powered by direct-current electricity and which has an electronically controlled commutation system, instead of a mechanical commutation system based on Brush es....
. AC-powered fans usually use mains voltage, while DC-powered fans use low voltage, typically 24 V, 12 V or 5 V. Cooling fans for computer equipment exclusively use brushless DC motors, which produce much less electromagnetic interference

Electromagnetic interference

Electromagnetic interference is an unwanted disturbance that affects an electrical circuit due to either electromagnetic conduction or electromagnetic radiation emitted from an external source....
.

In machines which already have a motor, the fan is often connected to this rather than being powered independently. This is commonly seen in cars, boats, large cooling systems and winnowing machines, where the fan is connected either directly to the driveshaft

Driveshaft

A drive shaft, driving shaft, propeller shaft, or Universal joint#History shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement between them....
or through a belt and pulleys. Another common configuration is a dual-shaft motor, where one end of the shaft drives a mechanism, while the other has a fan mounted on it to cool the motor itself.

Solar powered fan

Electric fans used for ventilation may be powered by solar panel

Photovoltaic module

In the field of photovoltaics, a photovoltaic module or photovoltaic panel is a packaged interconnected assembly of photovoltaic cells, also known as solar cells....
s instead of mains current. This is an attractive option because once the capital costs of the solar panel have been covered, the resulting electricity is free. In addition, electricity is always available when the sun is shining and the fan needs to run.

A typical example uses a detached 10 watt

WATT

WATT is a radio station broadcasting a News radio-Talk radio-Sports radio format. Licensed to Cadillac, Michigan, it first began broadcasting in 1945....
, 12x12 inch (30x30 cm) solar panel and is supplied with appropriate bracket

Bracket

Brackets are punctuation marks used in pairs to set apart or interject text within other text. In computer science, the term is sometimes said to strictly apply to the square or box type....
s, cable

Cable

A cable is a large fiber or metal rope, used for hauling, lifting, or towing, or an assembly of two or more insulated electrical conductors, laid up together as an assembly....
s, and connector

Connector

Connector may refer to:* Electrical connector, a device for joining electrical circuits together** Audio and video connector** Gender of connectors and fasteners...
s. It can be used to ventilate up to 1250 square feet (100 m²) of area

Area

Area is a quantity expressing the two-dimensional size of a defined part of a surface, typically a region bounded by a closed curve. The term surface area refers to the total area of the exposed surface of a 3-dimensional solid, such as the sum of the areas of the exposed sides of a polyhedron....
and can move air at up to 800 cubic feet per minute (400 L/s). Because of the wide availability of 12 V brushless DC electric motor

Brushless DC electric motor

A brushless DC motor is a synchronous electric motor which is powered by direct-current electricity and which has an electronically controlled commutation system, instead of a mechanical commutation system based on Brush es....
s and the convenience of wiring such a low voltage, such fans usually operate on 12 volt

Volt

The volt is the SI SI derived unit of electric potential difference or electromotive force, commonly known as voltage. It is named in honor of the Lombard physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery ....
s.

The detached solar panel is typically installed in the spot which gets most of the sun light and then connected to the fan mounted as far as 20 to 25 feet (6 to 7 m) away. Other permanently-mounted and small portable fans include an integrated (non-detachable) solar panel.

External links

"the most powerful single axial-flow fan in the world".

Fan (mechanical)

History

Types of fans

Axial fans

Centrifugal fan

Cross flow fan

Fan motor

Solar powered fan

See also

External links