In one example, a FDB motor having a top-cover attached, EM biased bearing
system is provided. The motor includes a shaft and rotor disposed for
relative rotation, and an axial limiter for restricting axial movement of
the rotor with respect to the shaft, wherein the axial limiter is wet or
lubricated during contact. The limiter is spatially fixed with respect to
one of the shaft or the rotor and disposed with an axial end surface
opposing a surface portion spatially fixed with respect to the other of
the shaft or the rotor to form a gap therebetween. The gap may be filled
with a fluid such as bearing lubricant, thereby providing a lubricated or
wet contact surface to restrict axial movement of the shaft and rotor.
Additionally, one or both surfaces may include a groove or slot to
provide circulation of fluid through the gap.