Operation of Vacuum Cleaners

Posted by


Electric vacuum cleaners have become an essential household appliance in the past century. Their significance is evident when one considers the amount of dust and debris that would have to be manually removed from carpets without them.

When you drink soda with a straw, you use the simplest suction mechanism. The act of sucking creates a pressure drop between the top and bottom of the straw. The soda then gets pushed up towards your mouth due to the higher fluid pressure at the bottom of the straw.

A vacuum cleaner operates on the same principle, albeit in a more complex manner. In this article, we will examine the inner workings of a vacuum cleaner to determine how it uses suction to remove dust and debris from your home. The standard vacuum cleaner design is uncomplicated, but it relies on several physical principles to achieve effective cleaning.

The conventional vacuum cleaner comprises only six essential components:

  • An intake port that may include various cleaning attachments
  • An exhaust port
  • An electric motor
  • A fan
  • A porous bag
  • A housing containing all other components

When you plug in and turn on the vacuum cleaner, the following occurs:

  1. The electric current powers the motor. The motor is connected to the fan, which has angled blades similar to those of an airplane propeller.
  2. As the fan blades rotate, they push air towards the exhaust port (see How Airplanes Work to learn about the principle involved).
  3. When the air particles move forward, the density of particles, and thus the air pressure, increases in front of the fan and decreases behind it.

The pressure drop behind the fan is similar to the pressure drop in the straw when you drink through it. The air pressure behind the fan decreases below the ambient air pressure outside the vacuum cleaner. As a result, a partial vacuum is created inside the vacuum cleaner. The ambient air flows into the vacuum cleaner through the intake port since the air pressure inside it is lower than the pressure outside.

As long as the fan is operational and the vacuum cleaner’s passageway stays open, there will be a constant stream of air flowing through the intake and exhaust ports. But how does a flowing stream of air collect dirt and debris from your carpet? The answer is friction.

Did You Know?

Black and Decker’s space mission technologies led to the creation of the Dustbuster. Learn more about fascinating NASA innovations in this interactive animation from Discovery Channel.

Brushes and Bags in Vacuum Cleaners

When it comes to upright vacuum cleaners, rotating brushes are commonly found at the bottom. These brushes can be spun by the vacuum’s motor or by the air rushing through it.

As we learned in the previous section, the vacuum cleaner’s fan generates suction that creates a stream of air moving through the intake port and out the exhaust port. This stream of air works similarly to a stream of water. As the air particles move, they rub against any loose debris or dust. If the suction is strong enough and the debris is light enough, the friction will carry the material through the vacuum cleaner’s interior. This principle is the same as how leaves and debris float down a stream. Some vacuum designs feature rotating brushes at the intake port, which loosen dirt and dust from the carpet so the air stream can pick it up.

As the air filled with dirt makes its way to the exhaust port, it passes through the vacuum cleaner bag. These bags are typically made of porous woven material like paper or cloth that acts as an air filter. The tiny holes in the bag are big enough to allow air particles to pass through, but too small for most dirt particles. As a result, when the air current flows into the bag, all the air moves through the material, but the dirt and debris are collected in the bag.

The vacuum cleaner bag is essentially a filter that permits air to pass through but traps dirt inside.

You can place the vacuum cleaner bag anywhere between the intake tube and the exhaust port, as long as the air flows through it. In upright vacuum cleaners, the bag is usually the final destination on the path, and the air flows back outside immediately after being filtered. In canister vacuums, the bag may be positioned before the fan so that the air is filtered as soon as it enters the vacuum cleaner.

Using this basic concept, vacuum cleaner designers create a variety of vacuum cleaners with different suction capacities. In the next section, we’ll explore the factors that determine suction power.

Are you shopping for a vacuum cleaner?

Check out Consumer Guide Products to read vacuum cleaner reviews and compare prices before making a purchase.

Factors Affecting Vacuum Cleaner Suction

Vacuum cleaner attachments are used to concentrate the air flow as it enters the vacuum. Since suction power depends on the size and shape of the passage, different attachments are better suited for different cleaning tasks.

In the previous section, we learned that vacuum cleaners pick up dirt by moving a stream of air through an air filter (the bag). The suction power of vacuum cleaners depends on various factors. Suction can be stronger or weaker based on:

The vacuum cleaner works by generating strong suction through the motor that needs to turn at a good speed. However, when there is a blockage in the air passageway due to debris buildup in the vacuum bag, the air faces greater resistance, and the individual air particles move more slowly due to increased drag. Therefore, the vacuum cleaner works better when the bag is replaced than when it has been used for a while. The size of the opening at the end of the intake port affects the suction force, as narrower vacuum attachments create a stronger suction force and can pick up heavier dirt particles than wider attachments.

The upright and canister designs are the most typical types of vacuum cleaners that collect dirt in a porous bag. However, there are many other ways to configure the suction system, which we’ll explore in the next section. The central vacuum system, which turns the whole house into a cleaner, is becoming popular again. It uses a motorized fan to create suction through interconnected pipes in the walls, and the dirt is collected in a large canister that needs to be emptied only a few times a year.

The first vacuum cleaners used hand-operated bellows to create suction, but the electric vacuum cleaners that showed up in the early 1900s were an immediate success, even though they were sold only as a luxury item for many decades.

Wet/Dry Vacuum Cleaners

When it comes to tackling tough cleaning jobs, many people turn to wet/dry vacuum cleaners that can handle both solids and liquids. However, traditional filters made of paper or cloth would not be able to handle the liquid material, so these cleaners require a different type of collection system.

The basic design of a wet/dry vacuum cleaner is quite simple. As the air stream moves through the cleaner, it passes through a wider area that is positioned over a bucket. When the air stream reaches this larger area, it slows down due to the same reason that air speeds up when moving through a narrow attachment. This decrease in speed loosens the air’s grip, allowing liquid droplets and heavier dirt particles to fall out of the air stream and into the bucket. Once you finish vacuuming, all you have to do is empty the contents of the bucket.

One type of wet/dry vacuum cleaner is the steam cleaner, which applies cleaning fluid to the carpet, massages it in, and then vacuums up the fluid along with any dirt.

In the following sections, we will explore two other innovative types of vacuum cleaners: cyclone vacuums and robotic vacuums.

Cyclone Vacuums and Robotic Vacuums

James Dyson with the Root Cyclone™ DC07
Photo courtesy Dyson

A more recent development in vacuum cleaner technology is the “cyclone vacuum.” Invented by James Dyson in the 1980s, this machine does not use a traditional bag or filter system. Instead, the Dyson sends the air stream through one or more cylinders, following a high-speed spiral path. This motion functions similarly to a clothes dryer, roller coaster, or merry-go-round. As the air stream spirals around, all the dirt particles experience a significant centrifugal force that propels them outward, away from the air stream. The dirt simply collects at the bottom of the cylinder without the need for any filter.

The Root Cyclone™. High volumes of air simultaneously move through several cyclones, providing higher, continuous suction power.
Photo courtesy Dyson

The cyclone system is a significant improvement over conventional vacuum cleaners as there are no bags to replace, and the suction does not decline as more dirt is sucked up.

Robotic Vacuums

Until recently, even the most powerful vacuum cleaners still required someone to push them around. Robotic vacuums have changed the game, as they can clean all by themselves, thanks to a combination of motors, sensors and a navigation system. For more information on how robotic vacuums work, check out How Robotic Vacuums Work.

We can expect to see even more advancements in vacuum cleaner technology in the future, including new suction mechanisms and collection systems. However, the fundamental concept of using a moving air stream to pick up dirt and debris is likely to remain for years to come.

For additional information on vacuum cleaners and related topics, check out the links on the next page.

Additional Information

Related HowStuffWorks Articles

  • Learn about Robotic Vacuums
  • Discover Central Vacuum Systems
  • Explore How Washing Machines Work
  • Investigate How Clothes Dryers Operate
  • Uncover How Hot Air Balloons Function
  • Find out How Snow Makers are used
  • Gain knowledge on How Water Blasters Work
  • Learn the Science behind SCUBA
  • Understand How Air Conditioners Function
  • Question whether a vacuum-filled balloon would float
  • Explore why space vacuum doesn’t suck away Earth’s atmosphere
  • Get tips on How to Repair a Vacuum Cleaner
  • Read Carpet-Cleaning Advice

More Useful Links

  • Vacuum and Steam Cleaner Guide
  • Reviews and Prices of Upright Vacuums
  • Reviews and Prices of Canister Vacuums
  • Reviews and Prices of Compact Canister Vacuums
  • Reviews and Prices of Handheld Vacuums
  • Reviews and Prices of Stick Vacuums
  • Visit Stark’s Vacuum Cleaner Museum
  • Find Vacuum Cleaner Reviews on Epinions
  • Discover Dyson Cyclone Vacuum Cleaners
  • Explore Vacuum Cleaners on the Open Directory
  • Learn How to Buy a Vacuum Cleaner


1. What is a vacuum cleaner and how does it work?

A vacuum cleaner is a household appliance that is used to clean floors, carpets, upholstery, and other surfaces. The basic principle behind a vacuum cleaner is suction. The machine creates a partial vacuum which sucks up dust, dirt, and debris from the surface being cleaned. The suction is created by an electric motor that drives a fan or impeller which draws air into the machine through a nozzle or hose. The air, along with the dust and dirt particles, is then filtered and deposited into a dustbin or bag for disposal.

2. What are the different types of vacuum cleaners?

There are several types of vacuum cleaners available in the market, including upright vacuums, canister vacuums, handheld vacuums, stick vacuums, robotic vacuums, and central vacuums. Upright vacuums are the most common type and are best for deep cleaning carpets. Canister vacuums are more versatile and can be used on different surfaces. Handheld and stick vacuums are ideal for quick cleanups and hard-to-reach areas. Robotic vacuums are the latest innovation in vacuum technology and are fully automated. Central vacuums are installed in the home and have a network of pipes that carry dirt and debris to a central location for disposal.

3. What are the features to consider when buying a vacuum cleaner?

When buying a vacuum cleaner, there are several features to consider, including the type of flooring in your home, the size of your home, the amount of traffic in your home, the level of filtration, the noise level, the cord length, the attachments, and the price. For example, if you have a lot of carpets in your home, an upright vacuum with a motorized brush roll may be the best option. If you have pets, you may want to consider a vacuum with a HEPA filter to remove pet dander and hair. If you live in a small apartment, a handheld or stick vacuum may suffice.

4. How do you maintain a vacuum cleaner?

To ensure that your vacuum cleaner works efficiently and lasts longer, it is important to maintain it properly. Regular cleaning of the dustbin or bag, filters, brush rolls, and hoses is essential. Empty the dustbin or replace the bag when it is full. Clean the filters according to the manufacturer’s instructions. Check the brush rolls for tangled hair and debris and clean them. Inspect the hoses for blockages and clean them as necessary. It is also important to replace worn-out parts, such as belts and filters, as needed.

5. Can vacuum cleaners cause allergies?

Vacuum cleaners can cause allergies if they are not equipped with a high-efficiency particulate air (HEPA) filter. HEPA filters can trap tiny particles, such as dust mites, pollen, and pet dander, that can trigger allergies. It is important to choose a vacuum cleaner with a HEPA filter if you or anyone in your family suffers from allergies or asthma. Regular cleaning of the filters is also important to ensure that they work efficiently.

6. Can vacuum cleaners be used for other purposes?

Vacuum cleaners can be used for other purposes besides cleaning floors and carpets. For example, handheld vacuums can be used to clean car interiors, upholstery, and curtains. They can also be used to clean up spills and messes. Vacuum cleaners with attachments, such as crevice tools and dusting brushes, can be used to clean hard-to-reach areas, such as corners, baseboards, and ceiling fans. Some vacuums can also be used to inflate air mattresses, pool toys, and other inflatable items.

Leave a Reply

Your email address will not be published. Required fields are marked *