A bearing seal includes an outer seal easily displaceable in the radial
direction, an inner ring as a ring-shaped rigid portion not extendable in
the radial direction, an inner seal having a seal lip, and an outer ring
arranged on the outer peripheral portion of the outer seal, in which the
spring constant of the inner seal is set to be larger than the spring
constant of the outer seal. The sealing performance between the inner
seal and the pin is ensured by using the ring-shaped rigid portion as a
boundary. When the pin is displaced in the radial direction, the
ring-shaped rigid portion is integrally displaced with the pin via the
inner seal, and the displacement of the ring-shaped rigid portion can be
absorbed by the outer seal.