New-Tech Europe Magazine | October 2018

around which the rotor spins, just like the point on a spinning top. This approach, using the magnetic structure, means the rotor weight is not borne by the bearing sleeve, but by magnetic forces, which suspend the rotor in the air. This cuts down the friction between the inside of the bearing and the shaft. It also reduces the tilt and wobble problems found with traditional sleeve bearings. Although the magnetic structure significantly reduces the amount of contact between the inside of the bearing and the spinning shaft, the omniCOOL system also includes a specially hardened sleeve to provide higher resistance against any abrasion that may still occur. The enhanced sleeve design also provides heat-resistance up to 90°C, which is more than most sleeve bearings can tolerate. Testing shows that this enhanced, hardened bearing has a significantly longer expected operating life than a traditional sleeve bearing – 3.2 times longer at 70°C and as much as 5.5 times longer at 20°C (Figure 4). The other key difference between the omniCOOL system’s enhanced bearing and a standard sleeve bearing is the absence of the oil rings and Mylar washers. With the magnetic forces reducing abrasion, lubricant is no longer required, so these components can be removed. Doing so reduces friction, which in turn cuts down on noise and the amount of energy required to start and spin the motor. It also means the gases generated by rotational friction are free to escape, instead of solidifying and blocking up the bearing. A new alternative to traditional fan designs The combination of technologies found in the omniCOOL system bridges the gap between ball and sleeve bearings, providing a quiet, strong, long-lasting fan that is suitable for use at any angle and more cost-effective than ball bearing designs. For engineers, it provides a new alternative to cool electronic equipment without the traditional tradeoffs.

Figure 3: Diagram of CUI’s omniCOOL system

Figure 4: Comparing life expectancy of a traditional sleeve bearing and the omniCOOL system

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