Abstract: A rotary joint for maintaining a cryogenic supplying refrigerant comprises a vacuum use cylindrical shaft supported in rotatable condition, a rotary seal ring fitted to an outer circumferential face with a space, a stationary seal ring provided at both sides of the respective rotary seal rings, a resilient bellows to press the stationary ring resiliently to the rotary seal ring side, a spaced fluid passage formed between the respective resilient bellows, a second fluid passage communicating with the spaced fluid passage, a connecting fluid passage communicating with the second fluid passage, a first pipe communicating through the spaced fluid passage, a connecting cover having a suction bore for vacuumizing and a magnetic fluid seal device having a projection constituted as multiple gaps corresponding to a pressure of the vacuumizing.

Abstract: A rotary joint of the present invention maintains cryogenic temperature of a supplying refrigerant flowing through a fluid passage, and makes available to lubricate a seal face by the supplying refrigerant as well as to minimize a running cost for the refrigerant.

Abstract: A rotary joint of the present invention maintains cryogenic temperature of a supplying refrigerant flowing through a fluid passage, and makes available to lubricate a seal face by the supplying refrigerant as well as to minimize a running cost for the refrigerant.

Abstract: The present invention provides a rotary joint which is available to maintain a cryogenic supplying refrigerant which flows in a fluid passage by a vacuum thermal insulation so that a cooling portion is cooled certainly.

Abstract: A mechanical seal device includes a rotational seal ring connected to a rotational shaft, having a rotational seal surface and arc-shaped grooves arranged on the rotational seal surface. The grooves are sectionalized by partition walls. A stationary seal ring has a stationary seal surface facing the rotational seal surface of the rotational seal ring. A spring biases the stationary seal ring against the rotational seal ring. Outlet portions are formed on the stationary seal surface of the stationary seal ring and connect with a fluid supply path for supplying a pressure fluid. A circumferential direction length (W3) of each outlet portion is made to be ½ of a circumferential direction length (W1) of each partition wall or longer (W3?W1/2); and a circumferential direction length (W3) of the outlet portions is made to be shorter than a circumferential direction length (W2) of the arc-shaped grooves (W3<W2).

Abstract: A mechanical seal device, wherein a rotational seal ring (10) and a stationary seal ring are arranged to face to each other between a rotational shaft and a housing fit together, comprising a rotational seal ring (10) connected to said rotational shaft, having a rotational seal surface (11), and having a plurality of arc-shaped grooves (12) arranged on said rotational seal surface to be in a circular shape around an axis center of said rotational shaft, the grooves being sectionalized by partition walls (13); a stationary seal ring having a stationary seal surface facing to the rotational seal surface (11) of said rotational seal ring (10); a spring for pressing said stationary seal ring against said rotational seal ring; and outlet portions formed on said stationary seal surface of said stationary seal ring and capable of connecting with a fluid supply path for supplying a pressure fluid.