Pipe connecting structure

• US 20070236008A1
• Filed: 04/02/2007
• Published: 10/11/2007
• Est. Priority Date: 04/05/2006
• Status: Active Grant

• Current Assignee: Doowon Climate Control Co., Ltd.
• Original Assignee: Doowon Climate Control Co., Ltd.
• Inventors: Kim, Jong Chul, Lee, Hong Yeol, Hwang, Jung Uk, Sung, Ki Chun
• Granted Patent: US 7,766,391 B2
• Time in Patent Office: Days
• US Class Current: 285/206
• CPC Class Codes: B60H 1/00571 of liquid ducts, e.g. for coolant liquids or refrigerants
• CPC Class Codes: F16L 23/18 the sealing means being rings
• CPC Class Codes: F16L 41/086 fixed with screws

Abstract

The present invention provides a pipe connecting structure including a male flange block combined with a first pipe and a female flange block combined with a second pipe, which is fastened to the male flange block by fastening means, where a protrusion having a hole that communicates with the first pipe is formed through the male flange block, and an insert portion into which the protrusion is inserted is formed through the female flange block, and a sealing member to closely contact with the end face of the protrusion is seated on the bottom inside the insert portion, and the sealing member includes an inner sealing part of soft metal and an outer sealing part of rubber tightly fitted around the outer circumference of the inner sealing part. Therefore joints between pipes, a heat exchanger and a pipe, or two components can bear high pressures in a refrigerating cycle system using a CO₂ refrigerant, air tightness can be maintained under low and high temperatures without changes in quality and shape of a sealing members, and it is possible to prevent and minimize leakage of the refrigerant by preventing permeation of CO₂.

Claims

1. A pipe connecting structure for a refrigerating cycle system, comprising:

a male flange block combined with a first pipe; and

a female flange block combined with a second pipe, the female flange block being fastened to the male flange block by fastening means,

wherein a protrusion having a hole that communicates with the first pipe is formed through the male flange block,

an insert portion into which the protrusion is inserted is formed through the female flange block,

a sealing member closely contacting the end face of the protrusion is seated on the bottom inside the insert portion, and

the sealing member includes an inner sealing part of soft metal and an outer sealing part of rubber tightly fitted around the outer circumference of the inner sealing part.

2. The pipe connecting structure as set forth in claim 1, wherein a seating groove is circumferentially formed along the edge of the bottom inside the insert portion so that the outer sealing part is inserted into the seating groove.

3. The pipe connecting structure as set forth in claim 1, wherein the outer sealing part has a thickness t1 in the range of 1.2 to 2 times larger than a thickness of the inner sealing part to allow the sealing member to keep air tightness as the outer sealing member is pressed by the bottom of the insert portion and the end face of the protrusion.

4. The pipe connecting structure as set forth in claim 1, wherein the inner sealing part is made of soft metal and the outer sealing part is made of propylene-based or nitrol-based rubber for high elasticity and air tightness.

5. The pipe connecting structure as set forth in claim 1, wherein a prominence and a depression fitted to each other are formed on the combining surfaces of the inner sealing part of soft metal and the outer sealing part of rubber to increase combining force.

6. The pipe connecting structure as set forth in claim 1, wherein a step protrudes from the male flange block to uniformly distribute fastening force to the sealing member that is pressed when the male and female flange blocks are fastened by a bolt.

7. The pipe connecting structure as set forth in claim 1, wherein a fixing pin is inserted in the male flange block and the female flange block so that the protrusion is accurately inserted into the insert portion.

8. The pipe connecting structure as set forth in claim 1, wherein a step is formed at the male flange block and a counter step to fit to the step is formed at the female flange block so that the protrusion is accurately inserted into the insert portion.

9. The pipe connecting structure as set forth in claim 1, wherein a prominence or a depression is formed at the male flange block and a counter depression or a counter prominence to fit to the prominence or the depression of the male flange block is formed at the female flange block so that the protrusion is accurately inserted into the insert portion.

10. The pipe connecting structure as set forth in claim 1, wherein beads are circumferentially formed on the end face of the protrusion and the bottom of the insert portion to keep air tightness by pressing the inner sealing part.

11. The pipe connecting structure as set forth in claim 10, wherein engraved beads are formed on both sides of the inner sealing part to which the beads formed on the end face of the protrusion and the beads formed on the bottom of the insert portion are inserted.

12. The pipe connecting structure as set forth in claim 1, wherein beads that are pressed by the end face of the protrusion and the bottom of the insert portion are formed on both sides of the inner sealing part.

20. The pipe connecting structure as set forth in any one of claims 10, 11, 12, 15, and 18, wherein the beads have any one of a triangular, circular, and polygonal cross section.

13. A pipe connecting structure, comprising:

a male flange block combined with a first pipe; and

a female flange block combined with a second pipe, the female flange block being fastened to the male flange block by fastening means,

wherein the male flange block includes a protrusion with a hole that communicates with the first pipe,

the female flange block includes an insert portion into which the protrusion is inserted, and

a sealing member is fitted around the outside of the protrusion,

the sealing member includes an outer sealing part of soft metal and an inner sealing part of rubber closely contacting the inside of the outer sealing part.

14. The pipe connecting structure as set forth in claim 13, wherein the inner diameter Di of the inner sealing part of rubber is set smaller than the outer diameter Do of the protrusion to increase air tightness of the sealing member fitted around the outer circumference of the protrusion.

15. The pipe connecting structure as set forth in claim 13, wherein beads are circumferentially formed around the edge (on the combining surface) of the entrance of the insert portion of the female flange block to keep air tightness by pressing a side of the sealing member, and

beads are formed around the root end (on the combining surface) of the protrusion of the male flange block to keep air tightness by pressing the other side of the sealing member.

16. A pipe connecting structure, comprising:

a male flange block combined with a first pipe; and

a female flange block combined with a second pipe, the female flange block being fastened to the male flange block by fastening means,

wherein the male flange block includes a protrusion with a hole that communicates with the first pipe,

the female flange block includes an insert portion into which the protrusion is inserted, and

a sealing member is fitted around the outside of the protrusion,

a receiving groove to receive the sealing member is formed around the root end of the protrusion,

the sealing member includes an inner sealing part of soft metal and an outer sealing part of rubber closely contacting the outer circumference of the inner sealing part, and

a circumferential prominence to press the inner sealing part is formed around the edge of the entrance of the insert portion of the female flange block.

17. The pipe connecting structure as set forth in claim 16, wherein the receiving groove has a depth d2 equal to or smaller than the thickness t2 of the inner sealing part to closely press the sealing member inserted in the receiving groove.

18. The pipe connecting structure as set forth in claim 16, wherein beads are circumferentially formed on the bottom inside the receiving groove and on the circumferential prominence to keep air tightness.

19. A pipe connecting structure, comprising:

a male flange block combined with a first pipe; and

a female flange block combined with a second pipe, the female flange block being fastened to the male flange block by fastening means,

wherein the male flange block includes a protrusion with a hole that communicates with the first pipe,

the female flange block includes an insert portion into which the protrusion is inserted,

a sealing member is fitted around the outside of the protrusion,

a step to receive and seat the sealing member is formed on an outer circumference of the end of the protrusion, and

the sealing member includes an inner sealing part of soft metal and an outer sealing part of rubber entirely wrapping around the outside of the inner sealing part.

21. The pipe connecting structure as set forth in claim 19, wherein the inner sealing part is a ring having any one of cross sections of plate, rectangle, polygon, and circle.

22. A pipe connecting structure for a refrigerating cycle system, comprising:

first and second pipes that are connected and arranged to allow a refrigerant to circulate in the refrigerating cycle; and

connecting means that connects the first pipe to a second pipe,

wherein the connecting means includes;

a male flange block that includes a first pipe-combining hole to which the first pipe is fitted;

a first combining protrusion that protrudes from a surface of the male flange block in communication with the first pipe-combining hole;

a second combining protrusion that protrudes from the end face of the first combining protrusion and includes a first seating face inside the second combining protrusion;

a sealing member that is fitted around the outside of the second combining protrusion and seated in the first seating face inside the second combining protrusion;

a female flange block that includes a second pipe-combining hole bored from one side to insert the second pipe, a first protrusion-combining hole bored from the other side in communication with the second pipe-combining hole to insert the first combining protrusion, a second protrusion-combining groove formed around the edge inside the first protrusion-combining hole to insert the second combining protrusion, and a second seating face formed inside along the second protrusion-combining groove to seat a side of the sealing member; and

fastening means that fastens the male flange block to the female flange block.

23. The pipe connecting structure as set forth in claim 22, wherein the second combining protrusion includes vertical combining grooves that are formed perpendicular to the end face of the second combining protrusion.

24. The pipe connecting structure as set forth in claim 22, wherein the second combining protrusion has a plurality of horizontal combining grooves that are formed in communication with the vertical combining grooves in a predetermined horizontal length at predetermined intervals along the outer circumference of the second combining protrusion.

25. The pipe connecting structure as set forth in claim 22, wherein the second combining protrusion has the vertical combining grooves that are formed perpendicular to the end face at predetermined intervals along the outer circumference of the second combining protrusion and holding prominences that protrude outside at the end of the outer circumference of the second combining protrusion.

26. The pipe connecting structure as set forth in claim 22, wherein sealing beads protrude from the first seating face or the second seating face.

27. The pipe connecting structure as set forth in claim 22, wherein the sealing member includes an O-ring surrounding the outside of the second combining protrusion for sealing, and an inner sealing part that includes a through hole communicating with the first and second pipe-combining holes and seated on the first seating face inside the second combining protrusion.

28. The pipe connecting structure as set forth in claim 27, wherein the O-ring and the inner sealing part are integrally formed.

29. The pipe connecting structure as set forth in claim 28, further comprising:

a plurality of wings that protrude at predetermined intervals along the outer circumference of the inner sealing part and that have the ends fixed to the O-ring to maintain the space between the inner sealing part and the O-ring.

30. The pipe connecting structure as set forth in claim 28, wherein the ends of the wings are fixedly inserted in the O-ring and parts of the outside of the ends are covered by the O-ring.

31. The pipe connecting structure as set forth in claim 27, wherein the O-ring has a cross-sectional thickness t1 in the range of 1.0 to 2.0 times more than the thickness t2 of the inner sealing part.

32. The pipe connecting structure as set forth in claim 27, wherein the space D1 between the O-ring and the inner sealing part is set to have 1 to 2 times more than the thickness D2 of the second combining protrusion.

33. The pipe connecting structure as set forth in claim 27, wherein the O-ring is made of ethylene-base rubber (EPDN), fluorine-based rubber (FKM), or nitrol-based rubber (H-NBR).

34. The pipe connecting structure as set forth in claim 27, wherein the inner sealing part is made of a softer material than the male flange block or the female flange block, or the inner sealing part is given different hardness due to heat treatment and change of process when the inner sealing part is made of the same material as the male or female flange block, or made of a resin.

35. The pipe connecting structure as set forth in claim 22, wherein a step protrudes from a side end of the male flange block.

36. The pipe connecting structure as set forth in claim 22, wherein the male flange block is combined with the female flange block with a space H1 smaller than the height H2 of the step.

37. The pipe connecting structure as set forth in claim 35, wherein the height H2 of the step ranges from 0.3 to 1.5 mm and the bolt-fastening distance G, i.e. the distance between the centers of the pipes and the bolt ranges from 13 mm to 16 mm.

38. The pipe connecting structure as set forth in claim 22, wherein the holding prominences protrude from the end of the second combining protrusion less than the thickness of the O-ring.

39. A pipe connecting structure, comprising:

a male flange block combined with a first pipe; and

a female flange block combined with a second pipe, the female flange block being fastened to the male flange block by a bolt,

wherein the male flange block includes a protrusion that communicates with the first pipe,

the female flange block includes an insert portion into which the protrusion is inserted,

a primary sealer is provided at the middle of the protrusion for primary sealing,

a secondary sealer is provided at the root end of the protrusion for secondary sealing, and

a fixing pin is inserted into the male flange block and the female flange block so that the protrusion is accurately inserted into the insert portion.

40. The pipe connecting structure as set forth in claim 39, wherein the primary sealer is a rubber ring, and

the secondary sealer is a ring including a metal sealing part and a rubber sealing part combined with the metal sealing part.

41. The pipe connecting structure as set forth in claim 40, wherein the rubber sealing part is 1.05 to 2 times thicker than the metal sealing part.

42. The pipe connecting structure as set forth in claim 39, wherein the protruding length of the protrusion of the male flange block ranges from 12 to 18 mm.

43. The pipe connecting structure as set forth in claim 39, wherein the thickness of the male flange block and the bolt-fastening length (the distance between the centers of the protrusion and the bolt) ranges from 12 to 16 mm.

44. The pipe connecting structure as set forth in claim 39, wherein the fastening torque for the male flange block and the female flange block ranges from 10 to 14 Nm.