Enhancement of memory capacity in HDD micro- bearing

The aim of the presented paper is presenting the shapes of HDD micro-bearing journal, which have influence on the enhancement of memory capacity. Moreover the asymmetrically grooved lateral surfaces of journal bearings generate the asymmetric pressure distribution, which leads to concentric rotation and eccentricity of a rotor. Most of the stiffness coefficient due to asymmetric grooves and hyperbolic shapes of lateral journal surfaces are bigger than those of the conventional cylindrical micro-bearings without grooves. The damping coefficients and friction torque due to asymmetric grooves and hyperbolic shapes of lateral journal surfaces are slightly bigger than those of the conventional cylindrical micro-bearings without grooves. The asymmetric grooves of hyperbolic micro journal bearings may have advantages in terms of small whirls radius and large dynamic coefficients occurring during the bearing exploitation. The idea of seeking of the slide micro-bearings with optimum of the capacity memory was implied from the author's investigation of human joints, which fulfil the role of intelligent bio-bearings. This paper investigates the dynamic behaviour of HDD micro-bearings with hyperbolic journal lateral shapes, by solving the proper Reynolds equation and the equation of a motion of a HDD spindle system. This paper presents the friction forces calculation in hydrodynamic HDD micro bearing lubrication with hyperbolic shapes of journals.