A miniature spindle motor with fluid dynamic bearings for portable storage device applications

Abstract

This paper presents the design and fabrication of a miniature axial-gap spindle motor for small-formfactor 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 9 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.

A Review on Application of Dynamic Parameters of Journal Bearing for Vibration and Condition Monitoring

“…Liu et al [172] and Nes et al [173] studied that a major component of the data storage devices is the miniature spindle motor is used to spin the disk during data storage or data retrieval. For both miniature spindle motor and tiny fan, they are supported using journal bearings.…”

Microsphere-Based Microsensor for Miniature Motors’ Vibration Measurement

“…Miniature motors are widely used in various applications, such as aerospace, robotics, medical machinery, and intelligence manufacturing, mainly because of their high efficiency, high speed, fast response, good stability, and other superior characteristics [1][2][3][4][5]. Miniature motors have many parameters, among which the vibration of the miniature motor shaft (MMS) is one of the important parameters because the vibration of MMS is closely related to system control, condition monitoring, fault diagnosis, and model systems analysis.…”

“…(1) We combine a stretched single-mode optical fiber with a microsphere, with a diameter that is 5 µm, to fabricate a microsensor with a size in the micrometer scale. (2) The microsensor we propose overcomes difficulties encountered via conventional sensors in measuring the vibration of miniature motor shafts with diameters less than 1 mm or even microns within a confined space. (3) By exploiting the microsphere's focusing properties (PNJ phenomenon), it becomes possible to accurately concentrate a sub-micron-sized light spot onto the surface of the measured rotating shaft.…”

Design of Novel Hydrodynamic Grooved Journal Bearing with Dual-Layer Herringbone-Grooved Patterns

“…For small spindle motors and cooling fans, journal bearings are very important component to support their rational motion [1,2]. There are different kinds of journal bearings, such as fluid dynamic bearings (FDBs), ball bearings, or oil-lubricated bearings.…”