Abstract: A rotary joint capable of lubricating a sealing surface of a mechanical seal forming a fluid passage through which a gas flows using a liquid even when the liquid flows through only one fluid passage is disclosed. A rotary joint includes a plurality of mechanical seals provided in an axial direction in an annular space between a case body and a shaft body to form a first intermediate flow passage that connects a first outer flow passage and a first inner flow passage of a first fluid passage through which a liquid flows to each other and form a second intermediate flow passage that connects a second outer flow passage and a second inner flow passage of a second fluid passage through which a gas flows to each other.

Abstract: Provided is a rotary joint capable of lubricating a sealing surface of a mechanical seal forming a fluid passage through which a gas flows using a liquid even when the liquid flows through only one fluid passage. A rotary joint 1 includes a plurality of mechanical seals 7 provided in an axial direction in an annular space A between a case body 2 and a shaft body 5 to form a first intermediate flow passage 41 that connects a first outer flow passage 31 and a first inner flow passage 61 of a first fluid passage 11 through which a liquid flows to each other and form a second intermediate flow passage 42 that connects a second outer flow passage 32 and a second inner flow passage 62 of a second fluid passage 12 through which a gas flows to each other.

Abstract: A mechanical seal which defines an annular space formed between a case body and a shaft body is included. The mechanical seal includes: a first sealing ring having a first seal surface; a second sealing ring having a second seal surface which slidably contacts with the first seal surface; and a plurality of coil springs provided along the first sealing ring in a circumferential direction and configured to apply axial forces to the first sealing ring to press the first seal surface against the second seal surface. The plurality of coil springs are divided into a plurality of groups, and first regions in each of which occurring distortion is increased by the axial forces of the coil springs that belong to the group and second regions in each of which distortion is smaller than that in each first region are present alternately along the circumferential direction in the first sealing ring.

Abstract: Provided is a rotary joint that allows a case body to be made compact. A rotary joint includes: a cylindrical case body having a plurality of first flow passages formed therein; a shaft body having a plurality of second flow passages formed therein; rolling bearings and provided in an annular space formed between the case body and the shaft body; a plurality of tubular members provided in the annular space and each having a third flow passage formed for connecting the first flow passage and the second flow passage; a first seal configured to prevent leak of a fluid flowing through the first flow passage and the third flow passage; and a second seal configured to prevent leak of a fluid flowing through the third flow passage and the second flow passage.

Abstract: Provided is a rotary joint that allows a case body to be made compact. A rotary joint includes: a cylindrical case body having a plurality of first flow passages formed therein; a shaft body having a plurality of second flow passages formed therein; rolling bearings and provided in an annular space formed between the case body and the shaft body; a plurality of tubular members provided in the annular space and each having a third flow passage formed for connecting the first flow passage and the second flow passage; a first seal configured to prevent leak of a fluid flowing through the first flow passage and the third flow passage; and a second seal configured to prevent leak of a fluid flowing through the third flow passage and the second flow passage.

Abstract: A mechanical seal which defines an annular space formed between a case body and a shaft body is included. The mechanical seal includes: a first sealing ring 11 having a first seal surface; a second sealing ring having a second seal surface which slidably contacts with the first seal surface; and a plurality of coil springs provided along the first sealing ring 11 in a circumferential direction and configured to apply axial forces to the first sealing ring 11 to press the first seal surface against the second seal surface. The plurality of coil springs are divided into a plurality of groups, and first regions K1 in each of which occurring distortion is increased by the axial forces of the coil springs that belong to the group and second regions K2 in each of which distortion is smaller than that in each first region K1 are present alternately along the circumferential direction in the first sealing ring 11.