Foil bearing device

Abstract

In the present invention, a foil bearing device that rotatably supports a rotating shaft comprises an annular member having an insertion hole through which the rotating shaft is inserted, a top foil of arcuate cross section that is positioned between the inner peripheral surface of the annular member and the outer peripheral surface of the rotating shaft so as to surround the entire outer periphery of the rotating shaft, and a bump foil that supports the top foil from the outer peripheral side of the top foil and that is supported on the inner peripheral surface of the annular member. In a cross-section perpendicular to the center line of the top foil, the top foil includes a first region in which at least one through hole formed through the top foil has an angular position of 240 degrees or more and less than 360 degrees, and a second region in which the angular position at which there are no through holes formed through the top foil is equal to or greater than 0 degrees and less than 240 degrees, if 0 degrees is regarded to be the angular position of a virtual line extending upward in the direction of gravity from the center line of the top foil, the angular position increasing as the imaginary line rotates in the direction of rotation of the rotating shaft with the center line of the top foil as the center of rotation, and 360 degrees is regarded to be the angular position when the imaginary line has completed one rotation.

Dependencies are inferred from the claim text.