Patent ID: 8876116

Claim:
A sealing structure for sealing a clearance between two members liquid-tightly or air-tightly by a seal ring interposed therebetween: the seal ring comprises a slidable structure, which is configured to seal the clearance between the two members by a hydraulic pressure applied thereto, and to unseal the clearance between the two members by a relative movement thereof resulting from a thermal expansion thereof; wherein the slidable structure comprises a pair of slidable pieces arranged adjacent to each other in a width direction of the seal ring while being allowed to slide relatively in counter directions, each of the slidable pieces including a protruding portion and a recessed portion, the recessed portion including a circumferentially extending surface, an axially facing surface and a receiving face, and the protruding portion including a leading end face; and a guiding structure, which is configured to guide one of the slidable pieces in a direction away from the other slidable piece when the slidable pieces move ahead relatively as a result of thermal expansion of the seal ring; and wherein the seal ring further comprises a pair of openings opened between the slidable pieces when said one of the slidable pieces is isolated away from the other slidable piece; the leading end face of the one of the slidable pieces and the receiving face, the circumferentially extending surface, and the axially facing surface of the other slidable piece forming one of the pair of openings, the guiding structure comprises an inclined face formed on the leading end face of said one of the slidable pieces and an inclined face formed on the receiving face of the other slidable piece such that the inclined faces are opposed to one another with respect to the one of the pair of openings, the inclined faces being inclined with respect to a direction perpendicular to the axial direction, thereby producing an outward component of a pushing force between the inclined faces resulting from the thermal expansion of the seal ring in a width direction of the seal ring, the one of the slidable pieces being pushed axially away from the other slidable piece when the inclined faces contact one another.