Even when your house is clean, it's absolutely filthy! That's because most of the dust and dirt in your house is way too small to see. Fortunately, most of us can live without knowing this kind of truth about our homes; a quick run around with the vacuum cleaner is enough to keep us happy. Twenty-first century homes are packed with dozens of appliances and gadgets, but vacuums are one of the few most of us simply couldn't live without. We all know vacuums suck up dirt—but how exactly do they work? And what makes a modern-style cyclonic cleaner different from an old-style bag cleaner? Let's take a closer look!
Vacuum cleaner or suction cleaner?.The name "vacuum cleaner" is a bit of a giveaway when it comes to understanding how your machine works: vacuum cleaners work by suction. ("Suction cleaner" would be a better name than vacuum cleaner, in fact, because there's no actual vacuum involved. There is a difference in air pressure, but nowhere is there is an absolute vacuum.) If you've ever tried that cleaning trick with a tissue paper and a comb, you'll know how effective suction can be for removing dirt. If not, try it now! Wrap a piece of tissue paper around a comb. Breath out as far as you can and hold your breath. Place the comb and paper against your mouth. Now lean against a dusty armchair and press your mouth and the comb against it. Breath in sharply so, effectively, you are breathing straight through the comb. Take the comb away from your mouth and inspect the tissue paper. See how dirty it is!
Now imagine what would happen if you could keep this trick up for hour upon hour, just like a vacuum cleaner. Eventually, the dirt would build up on the tissue paper to such an extent that air would no longer flow through it properly. Your ability to clean—as a human vacuum cleaner—would be greatly impaired. This is a very important point: for a vacuum cleaner to work effectively, it has to maintain powerful suction the whole time. If its bag is full or its filters are clogged up, its suction will be dramatically reduced and it won't pick up dust. This is a problem that plagues almost every type of vacuum cleaner—even the bagless, cyclonic ones that are now so popular.