In a foil bearing (23) having a plurality of foils (26) disposed
in a gap between a rotating member (12) and a stationary mount member (25),
a moveable member (27) is disposed on a side of the stationary member opposite
to the rotating member so as to be rotatable with respect to the stationary mount
member, abutting members (30) extend from the moveable member toward the
associated foils through respective through-holes formed in the stationary mount
member, and a surface of the moveable member with which one end of each abutting
member is in contact is provided with a cam surface. In such a structure, by rotating
the moveable member and thus changing the length of the abutting members projecting
out from the surface of the stationary mount member, it is possible to vary the
range of movement of the foils and practically vary the stiffness of the same.