Abstract
This paper presents the design and fabrication of a miniature axial-gap spindle motor for small-form-factor optical storage applications. The motor features a fluid dynamic bearing (FDB) and is characterized by a high mechanical rigidity, excellent dynamic characteristics, and a zero cogging torque. The performance of this FDB motor is evaluated experimentally using a laboratory-built prototype. The results show that the motor has an excellent dynamic response, a small axial repeatable runout, a small tilt angle, a high rotational speed, and a low operating current. Furthermore, with overall dimensions of just 15.5 × 3.3 mm, the FDB motor is around 80% smaller than that presented by the current group in a previous study (Liu et al., J Magn Magn Mater 304:362–364, 2006). Consequently, the proposed motor represents an ideal solution for both existing and emerging miniaturized portable storage device applications.
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Acknowledgments
This study was supported by the Ministry of Economic Affairs of Taiwan. The authors would like to express special thanks to the Laser Application Technology Center, Industrial Technology Research Institute, for technologic help.
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Liu, CS., Lin, PD. & Tsai, MC. A miniature spindle motor with fluid dynamic bearings for portable storage device applications. Microsyst Technol 15, 1001–1007 (2009). https://doi.org/10.1007/s00542-009-0830-5
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DOI: https://doi.org/10.1007/s00542-009-0830-5