A sealed rolling bearing includes an inner ring and an outer ring defining
a bearing space therebetween. Axially inner and outer contact seals are
provided on each side of the bearing space to seal the bearing space. The
axially outer contact seals stop any splashed muddy water, thereby
keeping the lips of the axially inner contact seals and their sliding
contact surfaces free of muddy water. This prevents the lips of the
axially inner contact seals and their sliding contact surfaces from
becoming worn by muddy water. The axially inner contact seals thus
maintain high sealability even if the bearing is used in environments
where muddy water splashes.