Abstract: A heavy object supporting device includes: a mounting table which is arranged to face a base, and on which a supported object is mounted; an annular sealing member which is arranged between the mounting table and the base and can be elastically compressed in the direction in which the mounting table and the base face each other; and a separation preventing structure which prevents separation between the mounting table and the base. A space, which is defined by the mounting table, the base, and the sealing member, is formed as a fluid-filled space that is sealed in a state filled with fluid. The separation preventing structure is configured to allow the mounting table to be moved relative to the base in the facing direction and the direction orthogonal to the facing direction while maintaining the sealed state of the fluid-filled space.

Abstract: A hydrostatic pressure guide mechanism includes: a guide member having a smooth guide surface; a movement member having a slide surface facing the guide surface and an annular placement groove formed on the slide surface; an annular seal member (hermetically closing member) that is disposed in the placement groove and capable of hermetically contacting with the guide surface; an oil supply structure configured to supply an oil into a static pressure pocket on the slide surface surrounded by the seal member; and an oil recovery structure configured to recover the oil from the static pressure pocket, in which the oil recovery structure has a recovery hole that is formed in the static pressure pocket and is opened on the slide surface.

Abstract: A fluid sealing mechanism for sealing fluid being fed into a fluid pressure pocket formed between sliding surfaces which are formed on the opposing surfaces of an article being supported and a support for supporting the article, wherein a ring groove being fitted with a resilient ring for sealing fluid is made in the sliding surface of the support. Under a state where a regulation ring for preventing the resilient ring from jumping out of the ring groove is fitted over the re-silient ring, the regulation ring is fitted in the ring groove along with the resilient ring. When the fluid fed into the fluid pressure pocket reaches a specified pressure, the regulation ring comes into pressure contact with the sliding surface of the support along with the resilient ring, thus preventing the resilient ring from jumping out.