Vacuum cleaner
From Wikipedia, the free encyclopedia
A vacuum cleaner is a device that uses an air pump to create a partial vacuum to suck up dust and dirt, usually from carpeted floors, but also from tiled floors and other smooth surfaces. Most homes with carpeted floors in developed countries possess a domestic vacuum cleaner for cleaning. The dirt is collected by a filtering system or a cyclone for later disposal.
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[edit] History of the Vacuum Cleaner
[edit] Ives W. McGaffey
The first manually-powered cleaner using vacuum principles was the "Whirlwind", invented in Chicago in 1869 by Ives W. McGaffey. The machine was lightweight and compact, but was difficult to operate because of the need to turn a hand crank at the same time as pushing it across the floor. McGaffey obtained a patent for his device on June 5, 1869, and enlisted the help of The American Carpet Cleaning Co. of Boston to market it to the public. It was sold for $25, a steep price in those days. It is hard to determine how successful the Whirlwind was, as most of them were sold in Chicago and Boston, and it is likely that many were lost in the great chicago fire of 1871. Only two are known to have survived to the present day, one of which can be found in the Hoover Historical Center.
[edit] H. Cecil Booth
The first powered cleaner employing a vacuum was patented by H. Cecil Booth, a British engineer, in 1901. He noticed a device used in trains that blew dust off the chairs, and thought it would be much more useful to have one that sucked dust. He tested the idea by laying a handkerchief on the seat of a dinner chair, putting his mouth to it and sucking hard. Upon seeing the dust and dirt collected on the underside of the handkerchief he realised the idea could work. Booth worked to create a device operating on such principles, and patented such a machine in Britain: the large device, known as the Puffing Billy, was drawn by horses and parked outside the building to be cleaned; suction was then provided by an internal-combustion engine burning petrol (gasoline). Booth never achieved great success with his invention.
[edit] Walter Griffiths
In 1905 "Griffith's Improved Vacuum Apparatus for Removing Dust from Carpets" was another manually operated cleaner, patented by Walter Griffiths Manufacturer, Birmingham, England. It was portable, easy to store, and powered by "any one person (such as the ordinary domestic servant)", who would have the task of compressing a bellows-like contraption to suck up dust through a removable, flexible pipe, to which a variety of shaped nozzles could be attached. This was arguably the first domestic vacuum-cleaning device to resemble the modern vacuum cleaner.
[edit] James Murray Spangler
In 1906, James Murray Spangler, a janitor in Canton, Ohio, in the United States, invented an electric vacuum cleaner from a fan, a box, and a pillowcase. In addition to suction, Spangler's design incorporated a rotating brush to loosen debris.
[edit] Hoover
Spangler patented his rotating-brush design 1908, and eventually sold the idea to his cousin's "Hoover Harness and Leather Goods Factory". In the United States, Hoover remains one of the leading manufacturers of household goods, including cleaners; and Hoover became very wealthy from the invention.
In Britain Hoover has become so associated with vacuum cleaners as to become a genericized trademark. The word "hoover" (without initial capitalization) often is used as a generic term for "vacuum cleaner". Hoover is often used as a verb, as well, as in "I've just hoovered the carpet".
Hoover is also notable for an extremely unusual vacuum cleaner, the Hoover Constellation, which is canister type but lacks wheels. Instead, the vacuum cleaner floats on its exhaust, operating as a hovercraft. Introduced in 1952, they are quite collectable today, and are easily identified by the spherical shape of the cannister. They tended to be loud, had relatively poor cleaning power, and could not float over carpets. But they remain a very interesting machine; restored, they work well in homes of nostalgia buffs with lots of hardwood floors. Disposeable paper bags remain available.
In 1959 an updated Constellation with a stationary handle replaced the previous model and was made until 1980. These Constellations route all of the exhaust under the vacuum using a different airfoil. The updated design is rather quiet even by modern standards particularly on carpet as it muffles the sound. These models float on carpet or bare floor. They are typically worth more to collectors than the older version.
Hoover is in the process of re-releasing an updated version of this later model Constellation in the US (model # S3341 in Pearl White and # S3345 in stainless steel). It should be widely availble in the US sometime in September per Hoover. Changes include a HEPA filtration bag, a 12 amp motor, a suction turbine powered rotating brush floor head, and a redesigned version of the handle which was a beautiful design but tended to break.
The 5.2 amp motor on older US units provides respectable suction but they all lack a motorized brush head. Therefore they generally work better on hard floors or short pile rugs. Old units take hoover type J paper bags but the slightly smaller type S allergen filtration bags can be easily trimmed to fit the retaining notches on the old vacuums. The most highly collectible colors are pink and turquoise. Replacement motors are still available from Hoover US for some models.
Hoover made another hovering vauum cleaner model called the Celebrity in the late sixties or early seventies. It has a flatted "flying saucer" shape. Hoover added wheels to it make it a conventional canister model after a brief run as a hovering vacuum. It uses type H bags.
[edit] Post-World War II
For many years after their introduction, vacuum cleaners remained a luxury item; but after World War II they became ubiquitous among the rising middle classes. They tend to be more common in Western countries because, in some parts of the world, wall-to-wall carpeting is uncommon and homes have tile or hardwood floors, which are easily swept, wiped, or mopped.
[edit] How it works
A vacuum's suction is caused by a difference in air pressure. A pump reduces the pressure inside the tube. Atmospheric pressure then pushes the air through the carpet and into the tube, and so the dust is literally pushed into the bag.
[edit] Configurations
Vacuum cleaner configurations:
- Upright vacuum cleaners have the pump mounted directly above the suction intake, with the bag mounted on the handle, which rises to about waist height. Upright designs usually employ mechanical beaters, often rotating brushes, to help disturb dust to be vacuumed up. There are two types of upright vacuums. On a single-motor upright, the beater brush is driven by the vacuum motor via belt, while on a dual motor upright, the vacuum and beater brush are driven by separate motors. The dual motor upright is very common in commercial uprights.
- Canister (or cylinder) designs have the motor and bag in a separate canister unit (usually mounted on wheels) connected to the vacuum head by a flexible hose. Although upright units have been tested as more effective (mainly because of the beaters), the lighter, more manoeuverable heads of canister models are popular. Some upmarket canister models have "power heads", which contain the same sort of mechanical beaters as in upright units, although such beaters are driven by a separate electric motor.
- Wet vacs or wet/dry vacuums—a specialised form of the canister vacuum—can be used to clean up wet or liquid spills. They commonly can accommodate both wet and dry soilage; some are also equipped with a switch or exhaust port for reversing the airflow, a useful function for everything from clearing a clogged hose to blowing dust into a corner for easy collection.
- Back-pack vacs are commonly used for commercial cleaning: they allow the user to move rapidly about a large area. They are essentially canister vacuum cleaners, except that straps are used to carry the canister unit on the user's back.
- Built-in or central vacuum cleaners move the suction motor and bag to a central location in the building and provide vacuum inlets at strategic places throughout the building: only the hose and pickup head need be carried from room to room; and the hose is commonly 8 m (25 ft) long, allowing a large range of movement without changing vacuum inlets. Plastic piping connects the vacuum outlets to the central unit. The vacuum head may either be unpowered or have beaters operated by an electric motor or air-driven motor. The dirt bag in a central vacuum system is usually so large that emptying or changing needs to be done less often, perhaps once per year. The central unit usually stays in "stand-by", and is turned on by a flick on the handle of the hose. Such a unit also produces greater suction than common vacuum cleaners, because a larger fan and more powerful engine can be used when they are not required to be portable.
- Robotic vacuum cleaners move autonomously, usually in a mostly chaotic pattern ('random bounce'). Some come back to a docking station to charge their batteries, and a few are able to empty their dust containers into the dock as well.
- Small hand-held vacuum cleaners, either battery-operated or electric, are also popular for cleaning up smaller spills.
Most vacuum cleaners are supplied with various specialised attachments, tools, brushes and extension wands to allow them to reach otherwise inaccessible places or to be used for cleaning a variety of surfaces.
[edit] Recent developments
Vacuum cleaners working on the cyclone principle became popular in the 1990s, although some companies (notably Filter Queen) have been making similarly-designed vacuum cleaners since at least the 1960s. Modern cyclonic cleaners were adapted from industrial cyclonic separators by James Dyson in 1985. He launched his cyclone cleaner first in Japan in the 1980s at a cost of about US$1,800 and later the Dyson DC01 upright in the UK in 1995 for £200. It was expected that people would not buy a vacuum cleaner at twice the price of a normal cleaner, but it later became the most popular cleaner in the UK. Cyclonic cleaners do not use bags: instead, the dust collects in a detachable, cylindrical collection vessel. Air and dust are blown at high speed into the collection vessel at a direction tangential to the vessel wall, creating a vortex. The dust particles and other debris move to the outside of the vessel by centrifugal force, where they fall because of gravity, and clean air from the center of the vortex is expelled from the machine after passing through a number of successively finer filters at the top of the container. The first filter is intended to trap particles which could damage the subsequent filters that remove fine dust particles. The filters must regularly be cleaned or replaced to ensure that the machine continues to perform efficiently. Since Dyson, several other companies have introduced cyclone models, including Hoover, and the cheapest model is no more expensive than a conventional cleaner.
In early 2000 several companies developed robotic "vacuum" cleaners. Some examples are Roomba, Robomaxx, Trilobite and FloorBot. Although most do not create a vacuum for cleaning, these machines propel themselves in patterns across a floor, cleaning surface dust and debris into their dustbin. They usually can navigate around furniture and find their recharging stations. Most robotic "vacuum" cleaners are designed for home use, although there are more capable models for operation in offices, hotels, hospitals, etc. By the end of 2003 about 570,000 units were sold worldwide.[citation needed]
In 2004 a British company released Airider, a hovering vacuum cleaner that floats on a cushion of air. It is claimed to be light weight and easier to manoeuvre (compared to using wheels), although it is not the first vacuum cleaner to do this - the Hoover Constellation predated it by at least 35 years. (The Hoover Constellation did this with a simple hovercraft-type airfoil on the bottom, using the discharge to float the vacuum. Hoover hover-vacs are now sought-after collectibles with their distinctive round post-Sputnik space-age design, though they do not float on carpets.)
In 2005 it was announced that a British inventor had invented a cleaner which has a closed system which circulates air, picking up dust from the carpet in an air stream rather than using suction. He claims that the advantage of this system is that it does not blow air back into the room disturbing dust on furniture and it is capable of working at a much lower power, saving energy. At current this cleaner has not been manufactured due to a lack of interest from vacuum cleaner manufacturers.[citation needed]
[edit] Vacuum cleaner specifications
The performance of a vacuum cleaner, when mentioned at all by the manufacturer, can be measured by several parameters:
- airflow, in cubic feet per minute (CFM or ft³/min) or litres per second (l/s)
- air speed, in miles per hour (mph) or metres per second (m/s)
- suction, vacuum, or water lift, in inches of water or pascals (Pa)
The suction is the maximum pressure difference that the pump can create. For example, a typical domestic model has a suction of about negative 20 kPa. This means that it can lower the pressure inside the hose from normal atmospheric pressure (about 100 kPa) by 20 kPa. The higher the suction rating, the more powerful the cleaner. One inch of water is equivalent to about 249 Pa; hence, the typical suction is 80 inches of water.
The power consumption of a cleaner, in watts, is often the only figure stated. Many North American vacuum manufacturers only give the current in amperes (e.g. "12 amps"[1]) and the consumer is left to multiply that by the line voltage of 120 volts to get the power ratings in volt amperes (not quite the same as watts for AC current, see AC voltages). The power does not indicate how effective the cleaner is, only how much electricity it consumes. The amount of this power that is converted into airflow at the end of the cleaning hose is sometimes stated, and is measured in air watts: the units are simply watts; "air" is used to clarify that this is output power, not input electrical power. This is calculated using the formula:
| cleaning power (air watts) | = airflow (CFM) × suction (inches of water) / 8.5 |
| = airflow (m³/s) × suction (Pa) |
Air watts measured at the vacuum's motor can differ by as much as 50% (depending on the type of vacuum) from the the air watts measured at the end of the hose. This is most noted in Central Vacuums.
[edit] Electric mop
Some vacuum cleaners include an electric mop in the same machine: for dry and a later wet clean.
[edit] See also
[edit] External links
- Vacuum Cleaners - Online guide explaining advantages of different vacuum brands.
- Eight myths of vacuuming
- The Vintage Vacuum Cleaner Museum
- How Stuff Works - Vacuum Cleaner
- HEPA & ULPA Vacuum Cleaners - What They Can & Can’t Do for IAQ
- The Vintage Hoover Emporium
- Miele vacuum user guide archive
- Tips on stain removal for carpets
- Vacuum repair guides and maintenance tips
- Invention of the vacuum cleaner, by H Cecil Booth (excerpt)
[edit] References
- The origin of the vacuum cleaner - H. Cecil Booth, Transactions of the Newcomen Society, 1934–1935, Volume 15.
- Vacuum Cleaners - Energy Use - MTP, The Captive Air-Flow Cleaner - B. Edginton
