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View Full Version : Zero backlash ball screws. ( Would this work?)



ynneb
05-12-2005, 10:39 PM
The truth is I have never seen the inside of a ballscrew.

I was speaking with this guy the other day, and was trying hard to understand what he was explaining to me.
I think this is what he was describing about his new zero backlash ball screws.

I seem to always see posts about the backlsah in ballscrews. If this does work, then it seems like an obvious design that should have been thought of some time ago. Or was the guy pulling my leg, and this isnt a new idea?

miljnor
05-12-2005, 11:52 PM
if you put pressure on the balls they will not roll without lots of friction.. the grub screw would probably have to be made with its own free rolling ball. i think the reason ball screw idea works is becuase the rolling friction on the ball make the ball roll thru the cage the balls themselves have to have some free play.. not sure..

the best way to prove a concept is imperical... do it! and let all of us know! would be cool if it worked, becuase of the simplicity. But i think the friction will kill it.

ynneb
05-13-2005, 12:01 AM
Yes I think you are right. I guess if the grub screw was cupped to house the ball as you suggested, that would enable smoother movement.
I guess there is no reason why there cant be a few presure balls in series so as to spread the slippage load among them all.
Also I think a high pressure spring between the grubscrew and the balls would assist in keeping the pressure up, and allow for small variations in the screw itself.

As for doing it myself, the only tools I own are simple hand tools.
I was hoping someone else might give it a bash :) Who knows, it may turn out to be a bussiness idea for that person.

JFettig
05-13-2005, 12:10 AM
This maybe show you how they work,
http://www.negribossi.co.uk/newsletter/autumn2003/ballscrews.htm
usually they arent fit exactly(on rolled screws) so they have a little slop, one way is to push them against or together to remove the slop, another way is to put larger balls in it to remove the slop.
-edit- a good pic of a dual circut nut:
http://www.ee.polyu.edu.hk/staff/eencheun/WebSubject2/ch02-actuators_files/image024.jpg
Jon