The humble vacuum cleaner has undergone a serious makeover. Learn how these everyday devices keep our homes spic and span.
Vacuum cleaners work in a variety of ways, each largely dependent on the type of suction and filtering methods adopted. However, within the modern vacuum cleaner market, three main systems dominate, each using differing suction, separation and filtering techniques and technology.
The first common type is the direct fan variety, which can either use a bag or canister for dust storage. Direct fan vacuums suckup dirt through a large impeller mounted close to the brushbar- the cylindrical brush typically located at the front-bottom of the appliance – or suction opening. I The dirt is agitated, ie drawn, out of the carpet or other surface through the impeller and then deposited into the device’s storage container, either directly or through a filter. These units are generally used for industrial cleaning purposes, as they generate a high-volume, low-energy consumption airflow, however due to their low suction power and basic filtering system, they’re not so well suited to the domestic environment.
The second main type of vacuum is the cyclonic variety. These differ significantly from direct fan types, as instead of separating dust with a series of impellers and bag filters, they do so by exposing the dirt-filled air to large centrifugal (ie moving away from the centre) forces. This works by the cleaner sucking in airborne dust into a specialised collection vessel at a specific angle (at a tangent).
This process forces the air to generate a fast-spinning vortex, which through its centrifugal force, causes the dust particles trapped within it to move to the outside of the vessel. The dirt, once freed from the air vortex, then falls to the base of the container through gravity for later disposal. In addition, due to the dust being separated without using a bag or extensive series of filters, cyclonic vacuums can boast very high suction levels. As such, they are very popular in residential markets, as their continuous high levels of suction enable various attachments for particular tasks to be used with little to no loss of airflow.
The third and most recent addition to the vacuum market is the robotic vacuum cleaner. These small – often circular -devices operate automatically by analysing a room with a variety of positional, acoustic and visual sensors and then proceed to periodically sweep its floor. These units typically use impellers, compressed vacuum bins and a series of filters to draw in fine particulate dirt through their bottom-mounted brooms and brushes, before storing it internally for later manual extraction.
Due to the small-scale nature of these vacuum cleaners, they are commonly used for small residential or medical applications, however their suction volume and intensity matches neither direct fan nor cyclonic types and they do not generally accept attachments either which limits their usefulness.
Each of these three systems, as mentioned, uses one or more filters to remove particulate dust and dirt from the air, which all vacuums exhaust directly back into the immediate environment. These filters include standard bags, finely perforated paper or cloth containers, water tanks, plastic meshes, charcoal sheets and HEPA (high-efficiency particulate arresting) traps. Often, a combination of these filters is used within any given device, playing to each of their strengths. For example, charcoal sheets are especially good at removing odour particles, while HEPA traps specialise in capturing minuscule particles (as tiny as 0.3 micrometres).
Why is cyclonic cleaning so effective?
A landmark breakthrough in vacuum cleaner tech, cyclonic separation and filtration grants both power and efficiency.
1. Intake – Dirt-containing air is routed into the collection vessel via the brushbar or suction hole and thrown against its outer wall at a tangential angle.
2. Vortex – A vortex is generated by the air’s movement within the central bin, forcing large dirt particles and dust to be prised free and spun to the sides of the vessel.
3. Bin – The dirt, once free from the bin vortex, falls down the sides to the base of the container where it is stored. Typically, this bin can be manually removed by the user and simply tipped out with the general rubbish.
4. Filter – The remaining air-which may still be contaminated with fine dust – is then passed through an internal filter, trapping further dirt that may have been missed.
5. Mini-cyclones – Finally, the air is drawn up through the centre of the vacuum into a series of cyclones. Again the air is routed at a tangential angle, however their smaller size generates a higher velocity spin and allows even the smallest dirt particles to be captured, and again dropped into the bin below.
Facts about vacuum cleaners
2. Dyson – Today the foremost name in the vacuum industry is Sir James Dyson, a British engineer famed for creating bagless vacuum cleaners. It took him 5,000 prototypes to perfect.
3.Roomba – A recent addition to the market is the ¡Robot Roomba series of robotic cleaners. These small, circular devices use a variety of sensors to periodically clean a user’s home automatically.
4. Filtration – Vacuum cleaners can use a variety of methods to filter gathered dust, ranging from traditional material-capturing bags to water filters and cyclonic separation.
5. Suck-cess story – After Dyson perfected his bagless cleaner, every vacuum manufacturer rejected it. Dyson set up his own company and is now worth GBP 2.69bn (USD 4.2bn), according to Forbes.