Abstract: A friction wheel includes a ring and bearing assembly, the friction ring extending from opposite sides of the bearing and having an inner facing surface; a hub surrounding an inner passage sized for receipt of the ring and bearing assembly, and the hub including an annular lip extending therefrom on opposite sides of the hub; at least one cap having an annular rim sized and configured for secured attachment to the annular lip, and each cap including an annular sleeve extending therefrom, and wherein the ring is sized for engaged receipt of the annular sleeve; raised elements on the annular sleeve sized and configured for a friction fit against the inner facing surface of the ring; and wherein relative rotation between the at least one cap and the ring requires a force sufficient to overcome the friction fit between the raised elements and the inner facing surface of the ring.

Abstract: An information storage system includes a transducer having a loop of ferromagnetic material with pole tips separated by an nonferromagnetic gap located adjacent to a medium such as a rigid disk. During writing the separation between the pole tips and the media layer of the disk is a small fraction of the gap separation. Due to the small separation between the pole tips and the media layer, the magnetic field generated by the transducer and felt by the media has a larger perpendicular than longitudinal component, favoring perpendicular recording over longitudinal recording. The media may have an easy axis of magnetization oriented substantially along the perpendicular direction, so that perpendicular data storage is energetically favored. The transducer may also include a magnetoresistive sensor for reading magnetic information from the disk.