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Greaseless ball bearings: A revolutionary spin on a design that's been around for ages

Greaseless ball bearings: A re...
Coo Space claims it has massively reduced bearing friction by eliminating the cage generally used to keep balls separated in the bearing races
Coo Space claims it has massively reduced bearing friction by eliminating the cage generally used to keep balls separated in the bearing races
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Not ideal – this bearing starts out with its balls unevenly distributed. After a dozen or so revolutions in the grooved bearing, the balls are distributed evenly again.
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Not ideal – this bearing starts out with its balls unevenly distributed. After a dozen or so revolutions in the grooved bearing, the balls are distributed evenly again.
Coo Space's Autonomous Distributed Bearing spins significantly longer with up to 90 percent less friction than a standard bearing
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Coo Space's Autonomous Distributed Bearing spins significantly longer with up to 90 percent less friction than a standard bearing
Coo Space claims it has massively reduced bearing friction by eliminating the cage generally used to keep balls separated in the bearing races
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Coo Space claims it has massively reduced bearing friction by eliminating the cage generally used to keep balls separated in the bearing races
View gallery - 3 images

While the ball bearing might be among Leonardo Da Vinci's less celebrated inventions, it's arguably one of his most important. Though it was initially designed as part of his failed helicopter invention, it has stood the test of time – there are ball bearings of a similar design to Leonardo's in just about every moving machine.

The basic design in simple: in order to reduce rotating friction between two pieces, the bearing has an inner and an outer race. A number of balls roll in between these two races, allowing the smallest possible contact points between the inner and outer races. The balls roll a lot easier than the two pieces would slide against each other.

The ball bearing can only work if the balls are kept separated and evenly spaced throughout the races. Touching each other would produce friction, and uneven spacing would cause the bearing to be weak under loads from a certain direction. So most bearings use cages to separate and evenly space the balls.

These cages cause friction and to reduce this friction, you generally need to lubricate your bearings, often with thick grease to ensure a long lifespan.

All of which is a long way of getting around to this: Japanese company Coo Space has come up with a way to reliably space the balls out without needing a cage.

Coo Space's Autonomous Distributed Bearing spins significantly longer with up to 90 percent less friction than a standard bearing
Coo Space's Autonomous Distributed Bearing spins significantly longer with up to 90 percent less friction than a standard bearing

The Autonomous Decentralised Bearing (ADB) puts a small indentation, or groove, into the outer bearing race. As the balls slide over this tiny groove, they slow down ever so slightly, and then speed back up. This does nothing to affect the bearing's regular performance, but if two balls are touching each other as they cross over the groove, the first ball's deceleration puts a tiny brake on the second ball, which separates the two as they go around the races.

It's an incredibly simple and tiny change, but it does a remarkable job. In the video below, a bearing is rotated with a group of very unevenly spaced balls in it. Within a dozen or two turns, the groove has spaced them all out to just about even, and that's where they stay.

The bearing which a ball does not contact

Without the need for a cage, you can run these bearings unlubricated, and that's where the real performance benefits come in. Coo Space claims the ADB experiences as little as 10 percent of the friction of a regular ball bearing and demonstrates this by spinning a couple of bearings to show just how much longer they'll spin than a lubricated cage bearing. Hint: lots longer, which should come as no surprise to anyone who's played with a regular lubricated bearing.

Greaseless bearings that eliminate sliding friction #DigInfo

Coo Space is already manufacturing prototypes and looking to partner with larger manufacturers to bring the bearings to market.

Source: DigInfo

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29 comments
SubashchandraRaiG
this is a 'revolution' in bearings
Dziks
brilliant! I must try to 3D print it.
ElSmurf
It's a beautiful thing to see such an old technology be improved upon by such a simple change.
Fretting Freddy the Ferret pressing the Fret
I reckon less noisy (computer) fans can be designed at higher rpm for starters. Bio mimicry of whale fins deliver more efficient fan blades, now this! Innovation never stops!
Bob
I'm not sold yet. This might work for very light loads but that little indent will be like a speed bump under heavy loads and may pound the bearing to failure.
Old J Hawthorne
Great…one step closer to perpetual motion…it's gonna happen!
Stickmaker
You're confusing plain ball bearings with caged roller bearings. One of the best claimants to inventing the latter is John Harrison, in the late Eighteenth Century as part of his work on accurate clocks.
garrettholl
Bob - they note in the top video at 2:15 (https://youtu.be/wN0vhXGVHnI?t=2m15s) that there is clearance between the decelerating/accelerating ball and the inner race. This simply drops the load of the affected ball and places it on to the two surrounding balls. Should be pretty smooth.
Conny Söre
I want those in my bike! I'm fully aware that the major resistance on that bike is generated by the weight and drag of my fat arse but still. If all bearings on that bike rolled like this I'm sure it would be a better ride.
Mark Windsor
To assemble a normal ball bearing traditionally is done by feeding the balls in between the races with the inner race eccentric to the outer race, allowing for a larger gap. Once all the balls are in place, the cage is fitted to space the balls evenly, which also brings the two races back to a concentric state. So, with this ball bearing, how do they assemble it? It looks like they have more than a normal number of balls in the bearing race.