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Robust optimum design of fluid dynamic bearing for hard disk drive spindle motors / Hiromu Hashimoto in Transactions of the ASME . Journal of tribology, Vol. 134 N° 04 (Octobre 2012) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 134 N° 04 (Octobre 2012) . - 11 p. Titre : Robust optimum design of fluid dynamic bearing for hard disk drive spindle motors Type de document : texte imprimé Auteurs : Hiromu Hashimoto, Auteur ; Masayuki Ochiai, Auteur ; Yuta Sunami, Auteur Année de publication : 2012 Article en page(s) : 11 p. Note générale : tribology Langues : Anglais (eng) Mots-clés : robust  optimum  design;  fluid  dynamic  bearings;  hard  disk  drives;  dimensional  tolerances;  spindle  motors Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper describes the robust optimum design considering dimensional tolerances for fluid dynamic bearings (FDBs) of 2.5 in. hard disk drives (HDDs). Recently, 2.5 in. HDDs are widely used for mobile devices such as laptops, video cameras, and car navigation systems. Therefore, in mobile devices, high durability toward external vibrations is essential for high HDD performance. On the other hand, FDBs for HDD spindle motors are generally manufactured by mass production processes which will eventually require reduction of production costs. Consequently, the FDBs are demanded to be easily manufactured and expected to have an insensitive design with low variability of bearing characteristics due to manufacturing errors. In this paper, first, the vibration model of the spindle motor is constructed, and then the vibration experiment was carried out in order to verify the appropriateness of the vibration model. Second, the bearing characteristics are calculated considering dimensional tolerance using optimum design combined with the statistical method in which the dimensional tolerance is assumed to distribute according to the Gaussian distribution. The bearing characteristics are estimated by expectation and standard deviation. Finally, the results of this robust optimum design compared with ones of optimum design neglecting tolerance, and the validity of this technique, were clarified. It was found from the results that the tolerances of radial clearance and groove depth are important factors to be considered to reduce the variability of the amplitude and friction torque. In addition, the variability of the amplitude strongly depends on the groove depth. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE9000134000004 [...] [article] Robust optimum design of fluid dynamic bearing for hard disk drive spindle motors [texte imprimé] / Hiromu Hashimoto, Auteur ; Masayuki Ochiai, Auteur ; Yuta Sunami, Auteur . - 2012 . - 11 p. tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 134 N° 04 (Octobre 2012) . - 11 p. Mots-clés : robust  optimum  design;  fluid  dynamic  bearings;  hard  disk  drives;  dimensional  tolerances;  spindle  motors Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper describes the robust optimum design considering dimensional tolerances for fluid dynamic bearings (FDBs) of 2.5 in. hard disk drives (HDDs). Recently, 2.5 in. HDDs are widely used for mobile devices such as laptops, video cameras, and car navigation systems. Therefore, in mobile devices, high durability toward external vibrations is essential for high HDD performance. On the other hand, FDBs for HDD spindle motors are generally manufactured by mass production processes which will eventually require reduction of production costs. Consequently, the FDBs are demanded to be easily manufactured and expected to have an insensitive design with low variability of bearing characteristics due to manufacturing errors. In this paper, first, the vibration model of the spindle motor is constructed, and then the vibration experiment was carried out in order to verify the appropriateness of the vibration model. Second, the bearing characteristics are calculated considering dimensional tolerance using optimum design combined with the statistical method in which the dimensional tolerance is assumed to distribute according to the Gaussian distribution. The bearing characteristics are estimated by expectation and standard deviation. Finally, the results of this robust optimum design compared with ones of optimum design neglecting tolerance, and the validity of this technique, were clarified. It was found from the results that the tolerances of radial clearance and groove depth are important factors to be considered to reduce the variability of the amplitude and friction torque. In addition, the variability of the amplitude strongly depends on the groove depth. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE9000134000004 [...]