Thrust foil air bearing having downwardly movable top foil leading edge

A thrust foil air bearing usable in apparatuses comprising a stationary part, and a rotating part which rotates relative to the stationary part about a centerline, the thrust foil air bearing comprising:

• a lower plate coupled to the stationary part so as not to move relatively;
• a middle plate disposed on an upper surface of the lower plate and comprising a bump foil capable of elastic deformation;
• and
• an upper plate disposed on an upper surface of the middle plate to face the rotating part and comprising a top foil disposed on the bump foil to contact the rotating part,
• wherein the top foil comprises a leading edge disposed upstream on a basis of flow of air and provided to move downwards toward the lower plate by an air pressure generated by the rotation of the rotating part,
• wherein the top foil further comprises:
• a top foil body;
• and
• a first wing protruding upstream from the top foil body, the first wing being cantilevered with respect to the top foil body such that a rear end of the first wing is fixedly supported by the top foil body and a front end of the first wing is a free end, and the first wing being capable of elastic deformation in a vertical direction, and
• wherein the leading edge is provided at the front free end of the first wing.