An Overview of ZeroF Bearings

The core ZeroF bearing design uses a concentric set of circular neodymium magnets to handle high radial loads, supported by a set of ball and thrust washer elements that ensure optimal axial load handling potential.

Performance

ZeroF bearings can be utilized in products and applications with light to normal loads, running at a range of low to relatively high speeds.

ZeroF - A low-friction bearing

To demonstrate the low frictional moment of a ZeroF bearing it was tested against a range of 8mm deep groove ball bearings currently on the market.

The test involves driving each bearing to a high speed and recording the time required to wind-down to zero RPM.

The time taken to reach zero is an expression of their frictional moment. The longer the time period, the greater the reduction in friction exhibited by the bearing.

The ZeroF bearing is 400% more efficient than its nearest rival. Less friction means less energy loss.

Stiffness

Another key performance aspect is bearing stiffness. This is the ability of the bearing to resist deflection of a rotating shaft around its null position while carrying a load. While direct comparison between ZeroF bearings and steel based competitors shows markedly increased capacity by those competitors it needs to be understood that in a passive magnet bearing stiffness values do not fully explain the capacity of ZeroF bearings.

For a magnetic bearing the stiffness is a function of magnetic volume and air gap; the load carrying capability will increase as these parameters are changed.

This highlights the advantage of incorporating ZeroF bearings into the early design requirements as the load capacity of most bearings is excessive for the application.

The graph to the below compares a standard ZeroF bearing to market competitors while the second graph displays the results for different ZeroF bearing configurations.

As shown to the right different magnetic volumes in relation to air gaps have a range of values around their linear area, as the air gap decreases the force increases in a non linear fashion due to the magnetic fields and their interaction.

From this we can see where there is a need to increase stiffness without any loss of the benefits of ZeroF, this can be achieved by increasing the number of magnetic interactions for the bearing. The graph to the right shows the near linear increase in stiffness as these interactions are added.

Noise

The graph to the right shows comparative sound levels between a ZeroF bearing and competitor bearings running down from 2000 RPM to 0 RPM.

Performance Summary

To highlight the superior benefits of ZeroF® bearings over the competition a comparison is provided below.

	ZeroF	Other Bearings
Lower Friction
Stiffness
Lower Noise
Less Heat
No Lubrication
Maintenance-Free
Increased Lifespan
Energy Saving