US Patent 7580225 Tolerance ring having variable height and/or assymmetrically located bumps

A tolerance ring configured to reduce torque ripple for a pivot bearing in an actuator arm assembly. The tolerance ring comprises a cylinder having a predetermined length, and a first and a second row of contacting portions arranged around the surface of the cylinder, the contacting portions of the second row are circumferentially displaced with respect to the first row by a distance greater than zero but less than the distance of the contacting portion and the spacing between adjacent contacting portions in the first row.