"Andrew Gabriel" wrote in message
...
In article ,
Archon writes:
My argument still applies, Dyson broke the bag/filter ripoff no matter
what you say.

It came to light (in the patent trial I think) that Hoover did
consider buying the patent in the early days, but that was to
prevent cyclone technology coming to the vacuum cleaner industry
because they were concerned at loss of revenue from consumables
(bags, filters).

Bags were awful, they ripped, blocked, smelled bad and the phony ripoff
copies were everywhere.

The most obvious problem with them is that they can only work
if they block. If they don't block, that's because they aren't
trapping the dust (and that happens too). A cyclone removes
the dust from the air-path.


The cyclone action only moves air in a circular motion inside a chamber.
The dust and other small particles are actually caught by the replaceable
filter traps in the path of the air flow. The cyclone does not drop its
dirt payload on its way round the vacuum cleaner. The dirt falls off the
filter when it reaches a weight heavy enough to allow it to fall off, or you
take the filter out and clean it before it reaches that stage.

How the cyclone action works is very simple. You make a vacuum cleaner as
normal, with a lower pressure atmosphere action at the head unit (the bit on
the carpet that picks the dirt up). You draw the air / dirt mixture into a
chamber that contains a tapered tube. The top of the taper is four times
the diameter of the bottom. When air is blown across the top of the tapered
tube (commonly called the wide end), it causes the air in the tube to spin.

When the air begins to spin, it creates areas of high and low pressure in
the chamber surrounding the tube. The dirty air being sucked in is at high
pressure near the top of the cyclone chamber. Once the spin motion starts,
the air lower down in the cyclone chamber goes to a lower pressure, where
the dirt is to heavy to be lifted back out by the air motion (commonly known
as the narrow end of the tube). So the dirt stays in the chamber. Well,
most of the heavier bits do. The tiny particles are caught by replaceable
filters that you have to buy seperately, just like the old style bags.

The filters need to be replaced just as often, if not more frequently, as
would have replaced a bag in any other vacuum cleaner. But the big bits of
crap getting caught in that chamber, really looks impressive, don'it. Where
it's all actually a load of ballox.

It's not rocket science.

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