Looking for a fluid bearing

[DoctorColdSaw]

Hi All,

I'm making a self levelling mechanism using a weighted cage in a bearing. As the cage approaches horizontal the turning force to overcome any stick or friction in the bearing approaches zero. With an insufficiently free running bearing the cage does not self level. It gets stuck at 10 - 15 degrees off.

A complication is that the mechanism has to damp excessive rotation ie it can't be so free running that once set in motion it'll just swing back and forth ad nauseum.

My idea is to find a bearing which uses a non-newtonian fluid as it's bearing medium i.e. it has an inner & outer shell but no balls or rollers. The fluid carries the load.

I do know that such bearings exist but I cannot find anyone that sells or makes them. Searches for "fluid filled bearing" return hits for standard hydrodynamic bearings. Whether I can get a fluid filled bearing filled with a non-newtonian fluid remains to be seen.

Thanks for any pointers.

Wilson.

 

[Compositepro]

For low friction there are air or magnetic bearings. Perhaps a flex joint or hanging cable would be suitable for "self-leveling". Analytical balances use jeweled bearings or pivots and are self-leveling. An aluminum plate and a strong "C" shaped magnet make a zero friction damper.

 

[DoctorColdSaw]

The cage is half aluminium, half tungsten. The magnet idea is a good one and worth definite consideration.
Still and all, I would like to find out a bit more about fluid filled bearings.

Cheers,

Wilson.

 

[unclesyd]

There are several other approaches that you may want to checkout for your proposed bearing. I would search under Fludic Bearings, or Fluid Dynamic Bearings.

You also may want to look at Foil Bearings shown in the sites below.

http://www.miti.cc/

http://www.nasa.gov/centers/glenn/about/fs14grc.html

 

[MikeHalloran]

Hydrostatic bearings might meet your needs, but they mostly use Newtonian fluids.



Mike Halloran
Pembroke Pines, FL, USA