Magnetic head and disk tester with head centrally mounted on radially-moving, rotatable platform that surrounds disk

摘要

A positioning device includes a base platform (100) which bears linear slide mechanisms (102 and 104). Stationary shafts (106 and 108) of the slide mechanisms are rigidly attached to the base platform. Sliding bushings (110 and 112) are mounted into a movable housing (124) whose motion is governed by a first stepper motor (136). The translation range of the housing is limited by a stop post (148) mounted onto the base platform. The housing supports a ball bearing (130), which comprises an outer race (132) and an inner race (134). The inner race is rigidly attached to the housing. The outer race supports a rotatable platform (150). The rotational motion of the outer race of the bearing is governed by a second stepper motor (154). The rotatable platform bears a mechanical arm (172) which holds a transducing head (180) centrally disposed with respect to the bearing. The transducing head can be placed at any desired radial position with respect to a disk (168) which is mounted onto a spindle (162) by imparting a specified displacement to the slider mechanisms via the first stepper motor. The necessary angular orientation of the transducing head with respect to the disk can be achieved by rotating the ball bearing via the second stepper motor.