Nonsymmetric groove pattern design for precise micro-spindles

As the fluid dynamic bearing spindles are to be actively adopted to various small form factor mobile applications, mechanical specifications for the motors have been aggressively changed to pursue the fierce information technology sector market trend. One of the major technological challenges for the spindles to be successfully employed in the applications is the reduction of power consumption since the most of the mobile applications operate with a limited power source at relatively lower voltage. Recognizing implication of the power consumption that of course affects stiffness of the spindle, few of options for mechanical designers are available but either lowering rotational speed or adopting thinner lubricant. In the present work, a novel design solution for alleviating side effect of the lower stiffness spindle is introduced and verified.