bagleses

[singingrainbow]

Im wondering what every ones opinion is about what the most efficient bagless system is I know bagleses were invented to eliminate bags and spin the dirt around the filter to prevent suction loss but what works best? first there is filtered bagless like most dirt devils then single cyclone vacuums like the bissell power force bagless then dual cyclone vacuums like the hoover mach 4 then multi cyclone vacuums like the bissell healthy home vac then there is root cyclone vacs like most dysons finally there is level 3 root cyclone vacs like the latest dysons. I think that anything after dual cyclone to level 3 root cyclone vacs will prevent suction loss. But why did dyson change from dual cyclone to root cyclone I mean if dual cyclone did not lose suction why is root cyclone more effective?

 

[vintagehoover]

Dyson's system is the most efficient. It's been developed and patented by James Dyson and his army of design-engineers over a 30 year period. Dyson have discovered and protected all the best elements of cyclonic separation, leaving everyone else to use their cast-offs.

Dyson's Root Cyclone + Core Separator (AKA Level 3 Root Cyclone) is the most efficient bagless design, followed by the Root Cyclone design, followed by Dual Cyclone.

The claim 'No Loss of Suction' refers to the fact that the cleaner will pull exactly the same airflow and waterlift levels with the canister full as it will when it's empty. Performance is constant - it doesn't trail off as the cleaner picks up dust.

This is not true of bagged cleaners, all of which will experience a measurable drop in performance as the fine dust clogs the pores, making it harder for the air to pass though. This creates a 'back pressure', which reduces the cleaner's ability to carry dirt in.

All that is demonstrable scientific fact; the debatable issue is how much this loss in 'suction' compromises the cleaner's performance. Some cleaners will still pick up perfectly adequately with a bag which is 2/3rds full. It's the inefficiency of this system which annoys Dyson - why have a cleaner which stops working at full performance as you use it, when you could have one which has constant performance?

The answer is that some people just prefer a hygienic, sealed pouch of dirt which they can drop in a bin, without the risk of any allergens escaping. This is what bagged manufacturers emphasise - the hygiene factor of bags. Remember how Air-Way and Hoover used to suggest you burnt their disposable bags in your furnace to kill the 'germs and disease' within? The threat isn't TB anymore, it's allergens and dust mites - but the tactic is the same!

The Root Cyclone system is better than the Dual Cyclone system because it has a higher separation efficiency, and because it can handle more airflow - thus making the cleaner more powerful.

This is Dyson's first own-branded Dual Cyclone system, from the 1993 DC01.

 

[vintagehoover]

And here's an improved Dual Cyclone, from the DC03.

See that the single entry duct to the inner cyclone is gone, and has been replaced by a number of curved vanes? And although you can't really tell from the photo, the vortex finder (ie. the tube through which the air exits the cyclone) has been split with a central divider - this stops the column of air from spinning as it exits, improving separation efficiency.

 

[vintagehoover]

And here's the first Root Cylone system, from the DC07. This is a photo I took of a cutaway display model from the Dyson Press Office.

Instead of one big inner 'cone', we now have 7 smaller cones. Not only that but they're inverted - the forces involved (300,000 times the force of gravity!) mean than the cyclones work just as well upside-down! The fine dust is flung out of the tops of the cones, rather than falling out of the bottom. This was not an entirely new idea; James Dyson's first working prototype of Dual Cyclone technology actually had inverted cyclones.

This system was not only a lot more efficient (the smaller the cone, the higher the centrifugal force generated), but a lot more powerful because it can handle greater airflow. The earliest DC07s generated 300 airwatts, compared to the 90 airwatts of the original DC01. People actually found 300 airwatts too much - the suction made the hose 'fight' against the user, and the cleaner difficult to push on carpets. Dyson redesigned the soleplate with larger rollers, and reduced the suction to 280 airwatts.