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Ball bearings, no lube?

Posted: Tue May 26, 2015 4:10 pm
by clshore
No grease or oil?

http://www.pddnet.com/news/2015/05/japa ... cation=top

Claims that getting rid of the cage to space the balls eliminates most friction, eliminates need for lubrication.

Re: Ball bearings, no lube?

Posted: Tue May 26, 2015 4:55 pm
by Nikolas Ojala
Very nice!

I am sure that space industry will be extremely interested.

Re: Ball bearings, no lube?

Posted: Tue May 26, 2015 5:10 pm
by twl
Ceramic ball bearings have had that "no lube" ability for quite some time, along with lower moving mass, but the cost for ceramic bearings is probably higher.
I would pick ceramic ball bearings anyway, over these.
But, these are somewhat interesting.

Re: Ball bearings, no lube?

Posted: Wed May 27, 2015 4:51 am
by Kevin Johnson
The outer race has visible eccentricities in movement. See 1:10. I think vibration and load capacity should be looked into carefully.

Re: Ball bearings, no lube?

Posted: Wed May 27, 2015 6:17 am
by clshore
Yah,
I have my reservations about this too, just posted it as an interesting 'claim'.

Re: Ball bearings, no lube?

Posted: Wed May 27, 2015 8:34 am
by pdq67
Me too!

I will wait for long term real life over-the-road tests before I comment.

If this is so, then brennelling of the race should be a good thing....

pdq67

Re: Ball bearings, no lube?

Posted: Sat Jun 06, 2015 11:39 pm
by Dan Timberlake
Check out Fig 8 on page 21 here.
http://ntrs.nasa.gov/archive/nasa/casi. ... 006034.pdf

Without fully developed elastohydrodynamic ( rolling ) lubrication the balls and races will start to spall and even fail by other means at a fraction of the "standard" predicted catalog life.

I think Loads and rpm would have to be so low to take advantage of that technology as to be pretty much useless for most machinery.

Re: Ball bearings, no lube?

Posted: Sun Jun 07, 2015 8:02 am
by Kevin Johnson
Dan Timberlake wrote:Check out Fig 8 on page 21 here.
http://ntrs.nasa.gov/archive/nasa/casi. ... 006034.pdf

Without fully developed elastohydrodynamic ( rolling ) lubrication the balls and races will start to spall and even fail by other means at a fraction of the "standard" predicted catalog life.

I think Loads and rpm would have to be so low to take advantage of that technology as to be pretty much useless for most machinery.
Aside:

Author uses 'absorption' incorrectly on page 8 but 'adsorption' correctly on page 2. Author corrects the error on page 10 of NASA paper submitted several years later (http://archive.org/stream/nasa_techdoc_ ... 7_djvu.txt) .

Rothbart catches and corrects this error in his earlier paper in his paraphrasing of page 8: http://www.slideshare.net/mzrzory/rothb ... whill-2004

"The extreme-pressure additives in the lubricating fluid form a film on the surfaces by a chemical reaction, adsorption, and/or chemisorption."

Re: Ball bearings, no lube?

Posted: Fri Jun 19, 2015 12:55 am
by modok
There is nothing in the video about not requiring lube.
The author of the article thinks "grease has been essential", means these require no lube??? author of article clearly not very sharp on comprehension.

The concept is these bearings require no cage.
Looking at the design, it appears this is accomplished by putting those grooves in the outer race, so the loaded balls accelerate away from the ones behind them, instead of the opposite.
With a ball in a groove, if the contact is on the sides it will speed up, contact at outer end it will slow down. Planetary gears and how trains run on rails! Very interesting.
Seems reasonable that normally the loaded balls will have more contact at the base of the groove and slow down.

Re: Ball bearings, no lube?

Posted: Fri Jun 19, 2015 6:06 am
by Kevin Johnson
modok wrote:There is nothing in the video about not requiring lube.
The author of the article thinks "grease has been essential", means these require no lube??? author of article clearly not very sharp on comprehension.

The concept is these bearings require no cage.
Looking at the design, it appears this is accomplished by putting those grooves in the outer race, so the loaded balls accelerate away from the ones behind them, instead of the opposite.
With a ball in a groove, if the contact is on the sides it will speed up, contact at outer end it will slow down. Planetary gears and how trains run on rails! Very interesting.
Seems reasonable that normally the loaded balls will have more contact at the base of the groove and slow down.
The difficulty is that the spokesperson from Coo Space Ltd. suggests and supports this conclusion:

https://www.youtube.com/watch?v=wN0vhXGVHnI
Published on Sep 1, 2012


Even if the ball of Bowling does not have wax, it rolls.
Why is grease required at a bearing?
Since the ball and the cage always rubbed, grease was required for the bearing.
"A.D.B." which makes balls non-contact without a cage is introduced.
It is the model change for the first time in bearing 500 years.
https://www.youtube.com/watch?v=gJygDep-FSQ

But in this in this additional video by Coo Space, oil is mentioned as being a lubricant with even lower viscosity lubricants contemplated. (See 4:36)

If you read the patents, there is more than one source of sliding friction discussed ("jostling" for example) so if you want to criticize Jacob Meister then it should be on the basis that he did not do this.

https://www.google.com/patents/US8052330
https://www.google.com/patents/US8783958

Re: Ball bearings, no lube?

Posted: Sat Jun 20, 2015 12:20 am
by modok
I am reading between the lines to some degree.

Q: Why is grease required at a (steel) ball bearing?
A:because they could not use oil

It's like asking why the chicken crosssed the road, or if the egg came first. That is too DUMB to be taken literally!!!
I am sure we all understand the basics clearly, cageless bearings are common, bearings do not all use grease, and steel rusts. He knows this too!

You can read between the lines differently if you want, but when I read the engrish what I got out of it was:
I will translate for engineers:
"why do some ball bearings often require high viscosity lubricant with a lot of EP additives? Because there is significant, and differing types of friction which requires this heavy oil, and consumes the additives in a caged ball bearing.
Our invention allows thinner lubricants with less additives to be used, because sliding friction is reduced."