How Vacuum Cleaner Works

When you sip soda through a straw, you are utilizing the simplest of all suction mechanisms. Sucking the soda up causes a pressure drop between the bottom of the straw and the top of the straw. With greater fluid pressure at the bottom than the top, the soda is pushed up to your mouth. This is the same basic mechanism at work in a vacuum cleaner, even a pet vacuum, though the execution is a bit more complicated. In this article, we’ll look inside a vacuum cleaner to find out how it puts suction to work when cleaning up the dust and debris in your house. As we’ll see, the standard vacuum cleaner design is exceedingly simple, but it relies on a host of physical principles to clean effectively.

It may look like a complicated machine, but the conventional vacuum cleaner is actually made up of only six essential components:

  • An intake port, which may include a variety of cleaning accessories
  • An exhaust port
  • An electric motor
  • A fan
  • A porous bag
  • A housing that contains all the other components

​When you plug the vacuum cleaner in and turn it on, this is what happens:

  1. The electric current operates the motor. The motor is attached to the fan, which has angled blades (like an airplane propeller).
  2. As the fan blades turn, they force air forward, toward the exhaust port 
  3. When air particles are driven forward, the density of particles (and therefore the air pressure) increases in front of the fan and decreases behind the fan.

As long as the fan is running and the passageway through the vacuum cleaner remains open, there is a constant stream of air moving through the intake port and out the exhaust port. But how does a flowing stream of air collect the dirt and debris from your carpet? The key principle is friction.The power of a vacuum cleaner is determined not just by the power of its motor, but also the size of the intake port, the part that sucks up the dirt. The smaller the size of the intake, the more suction power is generated, as squeezing the same amount of air through a narrower passage means that the air must move faster. This is the reason that vacuum cleaner attachments with narrow, small entry ports seem to have a much higher suction than a larger one.There are many different types of vacuum cleaner, but all of them work on the same principle of creating negative pressure using a fan, trapping the sucked-up dirt, cleaning the exhaust air and then releasing it. The world would be a much dirtier place without them.