Performance characteristics of actuator/bearing joints made with tolerance rings

Tolerance rings have been used for some time as a means of mounting the pivot bearing, providing significant benefits over alternative fixing methods, namely: retention, good rigidity and resonance performance, facilitation of rework, and consistent bearing torque, without the need for adhesive. A successful application of tolerance ring fixing technology is dependent on tolerance ring design, suitable mating component design, and on a controlled application process to ensure consistency of performance. Typically this has involved mounting the tolerance ring on to the bearing into a radial groove in the bearing sleeve. Whilst this is still the favoured arrangement, recent tolerance ring development has permitted higher retention forces to be developed on smaller, tighter structures, and raised the possibility of mounting the bearing directly without a sleeve. This has been achieved by careful design of the tolerance ring to increase its load generating ability whilst improving distribution of the load into the mating structures.