OT: Dyson Digital Motors

[Jamster]

It might just be my lack of experience but it seems this great new breakthrough in motors is just a different style of impellor, and instead of having brushes it has a chip creating an alternating magnetic field for the magnet... I'm no expert but I'm sure they've both been invented....

There are a few other points:

• It claims it is 104,000rpm here and 88,000rpm here.
• It claims that as the carbon brushes wear out on a normal motor this can be bad for the environment, I wouldn't have thought that in that quantity or at the rate in which they do is anything to worry about....
• It claims the iron core has no windings, then later goes on to say it does...

</rant>

I'm probably wrong but is this just a sales ploy to those that dont know any better? I'll admit there is definatly a difference....

Jamster

 

[JimPerry]

It claims it is 104,000rpm here and 88,000rpm here.


I'm probably wrong but is this just a sales ploy to those that dont know any better? I'll admit there is definatly a difference....

Jamster

being pedantic - it can spin at 104k but is used at 88k .. mainly marketing spin at 500k ?

Looks like a Brushless DC Motor - not "Rocket Science" but new for a cleaner.

 

[Jeremy Harris]

Nothing new about these motors at all. Dyson is just up to his favourite trick, disguising a well-known gadget as something "new". He did exactly the same with the cyclone vacuum cleaner, a gadget that had been used in industrial filtration for decades. The "digital" motor in a Dyson is just a simple BLDC motor, nothing fancy at all, and pretty much the same as the sort of motor that electric model aircraft folk have been using for years.

All Dyson has done is couple the high RPM capability of these motors (because they have no brushes the RPM limit is determined only by iron losses and physical strength of the rotor) with an efficient high speed impeller, similar to those used on turbochargers. Certainly he deserves credit for having taken some well-understood existing technology and applied it to a new application, but that's as far as his innovation goes.

 

[geoff07]

He might also have solved a few design, production and cost engineering issues along the way! But as a carbon-based life form I would have thought a bit of extra carbon wasn't a big deal.

 

[Jeremy Harris]

It's not the carbon from brushes, it's the ozone from the arcing that's the environmental issue. It's also pretty near impossible to get a small brushed motor to spin at the speeds that a small impeller like this needs, as keeping the commutator and brushes cool gets to be near impossible.

I'm not discrediting his engineering prowess in integrating existing technology into a new application like this, although given the very low cost of small, high power, BLDC motors and controllers I'm not at all sure his cost engineering is that great. For example, my electric boat (18ft long, two or three person, solar powered) uses a small BLDC motor and a cheap controller. The motor is rated at 2.8kW (optimistically, it has to be said) and cost around £35 as a one-off buy. The controller cost around £30, again as a one-off. This delivers a fair bit more power than the Dyson motor, too. I strongly suspect that the cost of the BLDC motor and controller in the Dyson is just a few pounds in total, meaning that they are probably charging a hefty premium for the BS factor...............

 

[techElder]

If you have done engineering at the level of the Dyson products, then the word "discrediting" might not cover it. You might add that you are not "sneering" at their accomplishments. (I don't think you were.) I'm pretty sure that it isn't a one man operation, and they most likely do feel like what they've accomplished is revolutionary ... for their market segment.

We used to talk about the "old" technology that NASA put into their space ships. "I've had more on my desktop for years!", we would say. I've known a NASA engineer. Believe me, they put more engineering design in and around that hardware than meets the eye.

It doesn't always pay to be too far out front.

 

[Jeremy Harris]

I certainly wasn't "sneering" as you put it, just pointing out that the technology in a Dyson isn't exactly cutting edge or particularly novel and it certainly isn't cheap to buy for what it is, yet the component cost is known to be fairly low. The way his company have integrated existing technology into different products is commendable, but it's not that technically complex or expensive.

For example, it would be possible to get pretty close to the fan system in a Dyson using off the shelf model parts (like those used in EDF units, for example), where these high speed, high power BLDC motors have been used for several years now. If you wanted to get get a higher pressure ratio than an EDF can deliver then I strongly suspect that an off-the-shelf small turbocharger impeller fitted to a high Kv EDF BLDC motor would do the job.

Certainly I agree that it doesn't pay to be too far out in front technically when producing simple consumer goods, but in this case Dyson has taken advantage of the availability of very high speed motors to allow the weight and size of a vacuum cleaner to be reduced (there's a direct relationship between mass airflow, impeller RPM and impeller diameter and throat size). That's a good thing, and probably the only worthwhile gain in terms of customer desirability.

I sincerely hope that Dyson have paid more attention to detail design and functionality with this new range than they did with the original range. I'm the sad owner of a (fairly expensive) Dyson DC01 that turned out to be a very poorly thought out design. For example, the exhaust air is expelled down and to the front, so it blows away the very stuff you're trying to sweep up. The cyclone is ineffective once even a small amount of material is collected, quickly leading to blockages in the filters. It is impossible to empty the machine without making a mess, as the main cyclone cone has to be brushed clean each time, meaning a trip to the end of the garden to brush it off.

 

[SAborn]

It just dont have the same effect calling someone a "Vortex" compared to a "Dirt Bag", what will the youth of tomorrow do as technology replaces insults?

 

[JimPerry]

It just dont have the same effect calling someone a "Vortex" compared to a "Dirt Bag", what will the youth of tomorrow do as technology replaces insults?

They'll just call you an "unfriend" or "blocked"