Rotary joint

Patent metadata

Field	Value
Publication number	US-11774018-B2
Application number	US-201917417948-A
Country	US
Kind code	B2
Filing date	Sep 25, 2019
Priority date	Dec 26, 2018
Publication date	Oct 3, 2023
Grant date	Oct 3, 2023

Abstract

Each of the mechanical seal devices of a rotary joint includes a first shaft side seal ring attached to a shaft body and a first case slide seal ring attached to one side of the first shaft side seal ring as well as a second case side seal ring attached to a case body and a second shaft side seal ring attached to the second case side seal ring. A first communication flow passage is formed between a first sliding portion of the first seal rings and a second sliding portion of the second seal rings. A second communication flow passage is formed between the first sliding portion of a mechanical seal device disposed on one side in the axial direction and the second sliding portion of a mechanical seal device disposed on the other side in the axial direction in mechanical seal devices adjacent to each other.

First claim

The invention claimed is:

1. A rotary joint comprising:
a tubular case body in which a plurality of outer flow passages is formed by openings on an inner circumferential side, a sealed fluid flowing through the outer flow passages;
a shaft body relatively rotatably provided in the case body, a plurality of inner flow passages through which a sealed fluid flows being formed therein by openings on an outer circumferential side; and
a plurality of mechanical seal devices disposed side by side in an axial direction in an annular space formed between the case body and the shaft body,
wherein each of the mechanical seal devices includes
a first shaft side seal ring attached to the shaft body,
a first case side seal ring attached adjacent to one side of the first shaft side seal ring in the axial direction in the case body to slide relative to the first shaft side seal ring,
a second case side seal ring attached to one side in the axial direction with respect to the first case side seal ring in the case body, and
a second shaft side seal ring attached adjacent to one side of the second case side seal ring in the axial direction in the shaft body to slide relative to the second case side seal ring,
a first communication flow passage that partitions the annular space and connects one of the outer flow passages and one of the inner flow passages is formed between a first sliding portion of the first shaft side seal ring and the first case side seal ring and a second sliding portion of the second shaft side seal ring and the second case side seal ring in each of the mechanical seal devices, and
a second communication flow passage that partitions the annular space and connects another one of the outer flow passages and another one of the inner flow passages is formed between the first sliding portion of a mechanical seal device disposed on one side in the axial direction and the second sliding portion of a mechanical seal device disposed on the other side in the axial direction in mechanical seal devices adjacent to each other in the axial direction,
wherein the case body has an axial cooling flow passage, through which a cooling fluid flows, formed to extend in the axial direction independently of the annular space.

2. The rotary joint according to claim 1 ,
wherein one of the plurality of mechanical seal devices disposed at one end in the axial direction further includes
a third shaft side seal ring attached to the shaft body on a side of the one end of one of the first sliding portion and the second sliding portion disposed on the one end side, and
a third case side seal ring attached to the case body adjacent to the one end side of the third shaft side seal ring to slide relative to the third shaft side seal ring, and
a third communication flow passage that partitions the annular space and connects still another one of the outer flow passages and still another one of the inner flow passages is formed between the one sliding portion and a third sliding portion of the third shaft side seal ring and the third case side seal ring.

3. The rotary joint according to claim 1 ,
wherein the case body has
a plurality of axial cooling flow passages formed in a circumferential direction thereof, and
a circumferential cooling flow passage that is formed to extend in the circumferential direction independently of the annular space and communicates with the plurality of axial cooling flow passages.

4. The rotary joint according to claim 3 ,
wherein the plurality of axial cooling flow passages includes a first axial cooling flow passage to which the cooling fluid is supplied from an outside of the case body, and two or more second axial cooling flow passages to which the cooling fluid is supplied from the first axial cooling flow passage via the circumferential cooling flow passage,
a cross-sectional area of the first axial cooling flow passage is formed to be smallest among the plurality of axial cooling flow passages, and
respective cross-sectional areas of the two or more second axial cooling flow passages are formed to gradually increase as a distance from the first axial cooling flow passage increases.

Assignees

• Nippon Pillar Packing

Inventors

• Suzuki Osamu
• Okunishi Yasuyuki
• Matsui Shuhei
• Ishijima Masanao

Classifications

• F16L27/08 Primary

  allowing adjustment or movement only about the axis of one pipe · CPC title

• F16L39/04

  allowing adjustment or movement · CPC title

• F16L39/06 Primary

  of the multiline swivel type, e.g. comprising a plurality of axially mounted modules · CPC title