The effect of spring pad loading and head penetration on the flight of flexible disk over a spherical head

A flexible disk, spinning at relatively low speed (80-600 r/min) and locally sandwiched between a spherical head and a spring loaded pressure pad, is investigated by stroboscopic white light interferometry. The contours of the disk in the vicinity of the head in general, and the minimum head/disk spacing in particular, are determined for various values of parameters such as disk speed, head penetration, and the pad loading force. Based on the topology of the contours, various modes of flight with distinctive characteristics are classified, and the effects of the head penetration and the pad loading force are thoroughly analyzed. Qualitative explanations of the observed phenomena are given and the problems associated with the optimum head design are discussed.