
h a l f b a k e r y
It's not a thing. It will be a thing.



account: browse anonymously, or get an account and write.



Please log in.

Asymmetric ball-bearing races

  [vote for,

In a ball bearing [link], we will assume that there are four lines on the races along which the balls make contact, two on the inner and two on the outer races (as in the second illustration in the article, captioned "a 4-point angular contact ball bearing"). Now, we'll make half of one race out of a different material, such that that different material is what's in contact with the balls along one of those four lines. This different material has a slightly higher or lower coefficient of rolling resistance with the bearing balls, compared to the material used for the other three-quarters of the races. The result is that the balls turn sideways (each one about a bearing-radial axis passing through its center) in a slow and somewhat controlled fashion as the bearing rotates. This has the obvious advantage of evening out wear over the surface of each ball, which could result in a longer-lived bearing.

Another, less obvious, advantage is that, in the application of a ball-bearing motor [link], each spot on each ball has a longer time of non-contact with the races between each moment of contact, as the bearing rotates. This means it has more time to cool down before needing to heat up again. This should increase the ball-bearing motor's endurance. (It often stops after only a few seconds of operation, due to the bearing balls overheating and expanding all over, meaning they can't expand at the contact points anymore, meaning there's no driving force for the motor. However, my contention is that the bearing balls don't actually expand all over, just around the ring that's been in contact with the races since the motor was started. If the balls are made to rotate sideways as well as rolling, this heating should be spread out over more of each ball's surface.)

N/A [2019-09-25]

notexactly, Sep 25 2019

Wikipedia: Ball bearing https://en.wikipedi...g/wiki/Ball_bearing
Mentioned in idea body [notexactly, Sep 25 2019]

Mike's Electric Stuff: Ball-Bearing Motor http://electricstuff.co.uk/bbmotor.html
Mentioned in idea body [notexactly, Sep 25 2019]


       // This has the obvious advantage of evening out wear over the surface of each ball //   

       No it doesn't, because with the existing symmetric design the rotation (libration? ) of the balls is pseudo-random; if you introduce a deliberate asymmetry, then the wear will also become predictably asymmetric, and the bearing will fail sooner.   

       [-] Bad Engineering.
8th of 7, Sep 25 2019

       // with the existing symmetric design the rotation (libration? ) of the balls is pseudo-random //   

       Ideally, yes. But, once a spot or a ring on ball wears down a little bit, won't the ball favor that spot or ring for further contact, since it's narrower in that axis? Won't that cause positive feedback in uneven wear? If it's a ring that it favors, which seems more likely, that positive feedback will be even stronger, because it will be very easy to stay in that rut; it'll start to act like a roller bearing.   

       As well, my forced rotation of the balls still isn't entirely deterministic. There's still a random component; it just forces that random component to be more uniformly spread out.
notexactly, Sep 26 2019

       //Asymmetric ball-bearing races// Hitler would have won.
MaxwellBuchanan, Sep 26 2019

       So no betting or unique carving and coatings.
wjt, Sep 28 2019


back: main index
