A double-wall pipe includes an outer pipe, and an inner pipe disposed inside the outer pipe. An outer wall of the inner pipe has thereon a ridge portion, which defines a groove portion extending in a longitudinal direction of the inner pipe. The outer pipe and the inner pipe are bent to have a strai
A double-wall pipe includes an outer pipe, and an inner pipe disposed inside the outer pipe. An outer wall of the inner pipe has thereon a ridge portion, which defines a groove portion extending in a longitudinal direction of the inner pipe. The outer pipe and the inner pipe are bent to have a straight portion extending straightly, and a bend portion bent from the straight portion. In the straight portion, the outer pipe has an inside diameter that is larger than an outside diameter of an imaginary cylinder defined by an outer surface of the ridge portion of the inner pipe. Furthermore, the ridge portion of the inner pipe contacts an inside surface of the outer pipe to be radially squeezed and held by the outer pipe, in the bend portion. The double-wall pipe can be suitably used for a refrigerant cycle device.
대표청구항▼
1. A double-wall pipe used as a heat exchanger for a refrigerant cycle on a vehicle, the double-wall pipe comprising: an outer pipe providing a piping for refrigerant of the refrigerant cycle on the vehicle; andan inner pipe providing a piping for the refrigerant of the refrigerant cycle on the vehi
1. A double-wall pipe used as a heat exchanger for a refrigerant cycle on a vehicle, the double-wall pipe comprising: an outer pipe providing a piping for refrigerant of the refrigerant cycle on the vehicle; andan inner pipe providing a piping for the refrigerant of the refrigerant cycle on the vehicle, disposed inside the outer pipe, the inner pipe having a plurality of helical ridge portions on an outer surface thereof, the helical ridge portions defining a plurality of helical groove portions extending in a longitudinal direction of the inner pipe, the plurality of helical ridge portions and the plurality of helical groove portions being formed on the outer surface thereof, wherein:the outer pipe and the inner pipe are bent to have a straight portion extending straightly, and a bend portion bent from the straight portion;the outer pipe has an inside diameter that is larger than an outside diameter of an imaginary cylinder defined by an outer surface of the helical ridge portions of the inner pipe, in the straight portion;the helical ridge portions of the inner pipe contact an inside surface of the outer pipe to be radially squeezed and held by the outer pipe, which is radially squeezed and deformed by bending in the bend portion;the helical groove portions define passages between the inner pipe and the outer pipe at the bend portion;all of the helical ridge portions directly contact the inner surface of the outer pipe in at least one cross-sectional view taken along a perpendicular cross section in the bend portion; andat least one of the helical ridge portions kept apart from the inner surface of the outer pipe in the straight portion forming a passage between the helical ridge portion and the inner surface of the outer pipe to allow the refrigerant flow between circumferentially adjacent two helical groove portions. 2. The double-wall pipe according to claim 1, wherein the number of the helical grooves is three. 3. The double-wall pipe according to claim 1, wherein the groove portions define a pitch that is 12 mm or above; the bend portion defines a bend angle that is not smaller than 10° (degrees); and the outside diameter of the imaginary cylinder defined by the outer surface of the ridge portions of the inner pipe in the straight portion is in a range of 0.8 to 0.95 of the inside diameter of the outer pipe in the straight portion. 4. The double-wall pipe according to claim 1, wherein the groove portions have a groove depth that is in a range of 5% to 15% of an outside diameter of the inner pipe. 5. The double-wall pipe according to claim 1, wherein the groove portions have a longitudinal length that is in a range of 300 mm to 800 mm. 6. The double-wall pipe according to claim 1, wherein the outer pipe has an outside diameter that is in a range of 1.1 to 1.3 times of an outside diameter of the inner pipe. 7. The double-wall pipe according to claim 6, wherein the outer pipe has a minimum outside diameter in the bend portion, which is equal to or larger than 0.85 times of an outside diameter of the outer pipe in the straight portion. 8. The double-wall pipe according to claim 1, wherein the outside diameter of the imaginary cylinder defined by the outer surface of the ridge portions of the inner pipe in the straight portion is in a range of 0.7 to 0.95 of the inside diameter of the outer pipe in the straight portion. 9. The double-wall pipe according to claim 1, further comprising a branch pipe branching out from a longitudinal end part of the outer pipe. 10. The double-wall pipe according to claim 9, further comprising a connecting pipe connected to a longitudinal end of the inner pipe. 11. The double-wall pipe according to claim 10, further comprising a holding member, which holds and fixes the branch pipe and the connecting pipe in a predetermined positional relation. 12. The double-wall pipe according to claim 11, wherein the holding member is brazed to the branch pipe and the connecting pipe. 13. The double-wall pipe according to claim 11, wherein the holding member is fitted to the branch pipe and the connecting pipe. 14. The double-wall pipe according to claim 9, wherein the branch pipe is disposed to have a deformable portion for adjusting an end position of the branch pipe. 15. The double-wall pipe according to claim 14, wherein the deformable portion is a bending portion provided in the branch pipe. 16. The double-wall pipe according to claim 1, wherein at least one of the bend portions is provided in a longitudinal length of 700 mm of the outer pipe and the inner pipe. 17. The double-wall pipe according to claim 1, wherein the outer pipe and the inner pipe are made of aluminum. 18. A double-wall pipe used as a heat exchanger for a refrigerant cycle on a vehicle, the double-wall pipe comprising: an outer pipe providing a piping for refrigerant of the refrigerant cycle on the vehicle; andan inner pipe providing a piping for the refrigerant of the refrigerant cycle on the vehicle, disposed inside the outer pipe, the inner pipe having a plurality of ridge portions on an outer surface thereof, the ridge portions defining a plurality of groove portions extending in a longitudinal direction of the inner pipe, the plurality of ridge portions and the plurality of groove portions being formed on the outer surface thereof, wherein:the outer pipe and the inner pipe are bent to have a straight portion extending straightly, and a bend portion bent from the straight portion;the outer pipe has an inside diameter that is larger than an outside diameter of an imaginary cylinder defined by an outer surface of the ridge portions of the inner pipe, in the straight portion;the ridge portions of the inner pipe contact an inside surface of the outer pipe to be radially squeezed and held by the outer pipe, which is radially squeezed and deformed by bending in the bend portion;the groove portions define passages between the inner pipe and the outer pipe at the bend portion;the ridge portions are helical ridge portions winding around the inner pipe;the groove portions are helical groove portions winding around the inner pipe and defining a pitch that is 12 mm or above;the bend portion defines a bend angle that is not smaller than 10° (degrees);the outside diameter of the imaginary cylinder defined by the outer surface of the ridge portions of the inner pipe in the straight portion is in a range of 0.8 to 0.95 of the inside diameter of the outer pipe in the straight portion;all of the helical ridge portions directly contact the inner surface of the outer pipe in at least one cross-sectional view taken along a perpendicular cross section in the bend portion; andat least one of the helical ridge portions kept apart from the inner surface of the outer pipe in the straight portion forming a passage between the helical ridge portion and the inner surface of the outer pipe to allow the refrigerant flow between circumferentially adjacent two helical groove portions. 19. The double-wall pipe according to claim 18, wherein the groove portions have a groove depth that is in a range of 5% to 15% of an outside diameter of the inner pipe. 20. The double-wall pipe according to claim 1, wherein the outside surface of the ridge portions of the inner pipe is separated from or in partial contact with the inside surface of the outer pipe, in the straight portion. 21. The double-wall pipe according to claim 1, wherein the inner pipe is in contact with at least diametrically opposite two parts or three or more circumferentially spaced parts of the inside surface of the outer pipe. 22. The double-wall pipe according to claim 1, wherein the deformation of the outer pipe by squeezing the outer pipe in the radial direction at the bend portion is a deformation into an elliptic cross section, the deformation being provided by both stretching an outside of the outer pipe at the bend portion and shrinking an inside of the outer pipe at the bend portion, the stretching and shrinking being caused by bending the outer pipe at the bend portion. 23. The double-wall pipe according to claim 1, wherein the outer pipe is a pipe having a circular cross section at the straight portion, and the inner pipe is a pipe having a shape of a bellow. 24. The double-wall pipe according to claim 18, wherein the deformation of the outer pipe by squeezing the outer pipe in the radial direction at the bend portion is a deformation into an elliptic cross section, the deformation being provided by both stretching an outside of the outer pipe at the bend portion and shrinking an inside of the outer pipe at the bend portion, the stretching and shrinking being caused by bending the outer pipe at the bend portion. 25. The double-wall pipe according to claim 18, wherein the outer pipe is a pipe having a circular cross section at the straight portion, and the inner pipe is a pipe having a shape of a bellow. 26. The double-wall pipe according to claim 1, wherein the outer surface of the inner pipe does not contact the inside surface of the outer pipe at the straight portion. 27. The double-wall pipe according to claim 1, wherein the groove portions are not in contact with each other. 28. The double-wall pipe according to claim 18, wherein the outer surface of the inner pipe does not contact the inside surface of the outer pipe at the straight portion. 29. The double-wall pipe according to claim 18, wherein the groove portions are not in contact with each other. 30. The double-wall pipe according to claim 1, wherein the passages between the inner pipe and the outer pipe at the bend portion extend into the straight portion, each passage is formed by adjacent helical ridge portions and a helical groove portion disposed between the adjacent helical ridge portions, at least one passage is isolated from at least one other passage in the bend portion by the contact of the helical ridge portions with the inside surface of the outer pipe, the at least one passage is in communication with the at least one other passage in the straight portion by the outer pipe having the inside diameter that is larger than the outside diameter of the imaginary cylinder. 31. The double-wall pipe according to claim 18, wherein the passages between the inner pipe and the outer pipe at the bend portion extend into the straight portion, each passage is formed by adjacent helical ridge portions and a helical groove portion disposed between the adjacent helical ridge portions, at least one passage is isolated from at least one other passage in the bend portion by the contact of the helical ridge portions with the inside surface of the outer pipe, the at least one passage is in communication with the at least one other passage in the straight portion by the outer pipe having the inside diameter that is larger than the outside diameter of the imaginary cylinder.
Wolfgang Geiger DE; Hans-Joachim Krauss DE; Michael Sickelmann DE; Karl-Heinz Staffa DE; Christoph Walter DE; Hagen Mittelstrass DE, Air conditioner with internal heat exchanger and method of making same.
Tsuchiya Shizuo,JPX ; Isaji ; deceased Akira,JPXITX by Tamiko Isaji ; legal representative, Heat exchanger having a double pipe construction and method for manufacturing the same.
Campbell Bonnie J. (Decatur AL) Counts Thomas G. (Decatur AL) Cunningham James L. (Decatur AL) Youtsey Karl J. (Decatur AL), Method of making double wall tubing assembly.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.