Temperature compensating mechanism for positioning of a magnetic head of a magnetic disk drive

摘要

A magnetic head actuator assembly for a disk drive, having dissimilar materials with different linear expansion coefficients, is provided with thermal compensation. The movable member of the actuator assembly has spring elements attached at spaced locations thereon and is associated with a cooperating pulley that drives a band. The band ends are connected to the spring elements such that rotation of the pulley imparts motion to the movable member. The spring coefficient of the band, spring, and connector structure between the pulley and one spaced location and the spring coefficient of the band, spring, and connecting structure between the pulley and the other of the spaced locations on the movable member are chosen so that the displacement of the magnetic head with respect to a record track on a cooperating disk surface caused by temperature variation is compensated. In one modification, a bimetal is used to replace a spring element in the thermal compensating system.