Magnetal AB a Swedish company with unique homopolar electrodynamic bearing technology for extreme high speed operations. Homepage www.magnetal.se Bearings to…
Magnetal Electrodynamic Bearings
May 30th, 2013 by admin
Magnetal AB a Swedish company with unique homopolar electrodynamic bearing technology for extreme high speed operations. Homepage www.magnetal.se Bearings to…
i would like to know if there needs to be any outside electrical input to sustain the high speed.
@camelsonhorizon
No outside electrical input is needed to control the bearing.
As a matter of fact thnks to this the EDB is capable of handing extremely fast events transient events – lets say an impact with extremely short duration (explosion for instance).
A contact ball bearing would in such an event have had all the steel balls crushed and an active magnetic would not manage to send out control signals.
We will shortly post a simulation showing this remarkable feature.
Can a bearing of this type be constructed which could have a large bore shaft of any size and keep the inside to outside diameter thickness at a minimum? I am looking to create a vortex tube and the shaft size needs to be rather large. The shaft would actaully be a tube casing with a ID of at least 6 inches.
Dear AmeriKraine
You are absolutely spot on! This type of bearing actually benefits from having a large diameter. The bigger the better. This has to do with the surface area of the magnets that makes most of the important parameters increases by the square.
There are three different types of bearings. 1. The inner rotor bearing – as you would imagine a normal bearing. 2. Outer rotor, 3. Intermediate (Hollow shaft) with magnets on the inside as well as on the outside.
WBR
Magnetal AB
the magnet are diametic 180 segment 2 segment per side( total 4 segment)? other wise the metal conducting rotor would be drawn to the onside of the magnet
pleease clearify how the contor rortor stay center other wise?
Dear olid777
I am not shure that I understand your description of the system. We have two or more magnets put together. The rotor is made of a conducting material such as copper. Copper is not magnetic (this is not entirely true since copper does contain some magnetism but generally not enough to make a real difference). Thus is not the rotor drawn to one side. Also the magnetic fields are balanced in a cunning way.
I hope this was an adequate anser to your question.
WBR
Magnetal AB.
So, where are your HED bearings available?
I would like to put a couple to the test.
i can see how it stops the side to side play not sure how it would stop the up and down play and im still waiting for an ancer from my email about prices
where can i get some?
Dear @crafter2u
You can contact us at Magnetal at [email protected]
Dear @Appliance0fScience
Please forgive me for late answer. You can order at [email protected]
i like your consept mine is a slightly diffrent design i never used the bearing to stop up and down play. I have been using mine for a few years now tho. Thanks for the wake up call need to move my project on, cant believe how close people are to the big break through
Fantastic!
The genius project. I could see the PhDThesis about it, and presented is simply fantastic.
Many thanks for the compliments.
Hi!
I would like to know about its application to energy storage flywheels. In that case will the hub or the shaft be the rotor for the EDB?
It is very expensive the bearings. Price for one – approximately 2000 euro.
Well the rotor would be on the outside – making it an outer runner bearing. Thus the magnets of the stator would be on the static shaft.
The type of bearing shown in this clip is of an inner runner type.
Hope this explains it.
WBR
Magnetal
Dear engfgaspar – thanks for the kind comment.
There is a PhD Theis and it can be found at magnetal.se (old page) under “Technology”. The PhD was put forward at the Swedish Royal Institute of Technology in Stockholm.
WBR
Magnetal
Thanks 1BustedMyth!
Dear Centurys822
You are correct. The bearing offered right now is of a Research & Development version – tailor made for tests. This specific bearing is made in a very small series – this is thus reflected in the current price.
In high volume production the bearing is comparable in price with a ceramic ball bearing. This is the only thing joining the two – the EDB outperforms the ceramic bearing by far.
The price is one reason why we don’t offer this bearing to other than R&D-departments.
Please view Magnetal new homepage at .com instead of .se
Furthermore we can be compared to an active magnetic bearing in some aspects, but to a fraction of the cost.
We have customers using ball bearings that last about 20 hours (!). The EDB will last for about 20 years or more. The pay back time (without taking into account cost for downtime, maintenance personnel) is quite quite short.
does it mean when the shaft is stationary (0 rpm) or rotating slowly, the bearing will not work?