GB2382133A

GB2382133A - Heat exchanger tube with stone protection

Info

Publication number: GB2382133A
Application number: GB0211471A
Authority: GB
Inventors: Gregory A Whitlow; Wen Fei Yu
Original assignee: Visteon Global Technologies Inc
Current assignee: Visteon Global Technologies Inc
Priority date: 2001-11-19
Filing date: 2002-05-20
Publication date: 2003-05-21
Anticipated expiration: 2022-05-20
Also published as: US20030094260A1; GB0211471D0; DE10218094A1; GB2382133B

Abstract

Attached to nose ends 21 of a heat exchangers tube 20 are first and second projections 26a, 26b (fig 2A), 41a, 41b (fig 4) spaced from one another so that they do not form an enclosed space and collapse when hit by an object such as a stone that passes through a radiator grill of an automobile in order to protect the tube 20. The projections may be straight and parallel to each other, curved and face each other and end in a point thus providing better protection than the straight projections, or curved and face each other and end in a flat part (fig 5) and provide the maximum protection. The tube 20 comprises a peripheral wall 22 having an elongated circular cross sectional shape, a plurality of compartments 24 and 24a connected to flat wall portions 25 and divided from one another by divisional walls 23. Compartment 24a may be elongated cross sectional shape, an elliptical shape or perfect circular shape. Compartments 24 are typically rectangular in cross sectional shape but maybe triangular, trapezoidal, circular or a star shape. The tubes may be used in a condenser for an automobile, residential condenser and radiator oil cooler.

Description

HEAT EXCHANGER TUBE WITH STONE PROTECTION APPENDAGE

BACKGROUND OF THE INVENTION

Field Of Invention

The present invention relates generally to a heat exchanger 5 tube for use in a heat exchanger and, more particularly, to a heat exchanger tube with a stone protection appendage.

Discussion Of Related Art Fig. 1 shows a cross-sectional view of a conventional heat exchanger flat tube of this kind. The heat exchanger tube 11 10 is made by extruding an aluminum article. The tube 11 has a peripheral wall 12 having an elongated circular cross-

sectional shape and a plurality of divisional walls 13, 13a connecting flat wall portions 12a of the peripheral wall 12.

The divisional walls 13 divide an inside space of the tube 11 15 to form a plurality of unit passages 14, 15 arranged in a lateral direction of the tube 11. Each divisional wall 13, 13a has a constant thickness along the height thereof so that a contact area with the heat exchanging medium can be enlarged, thereby enhancing the heat exchanging performance 20 of the tube 11. The tube 11 includes outermost unit passages 14 and intermediate unit passages 15 located between the outermost unit passages 14. Each intermediate unit passage 15 has a rectangular cross-sectional shape, and each outermost unit passage 14 has a semi-circular cross- sectional shape at 25 a lateral outside portion and a rectangular cross- sectional shape at lateral inside portion. Further, each portion of the tube 11, i.e., the peripheral wall 12 and the divisional walls 13, 13a, are formed to be as thin as possible for the purpose of lightening the weight of the tube 11.

- 2 Further, when the above-mentioned tube 11 is used in a condenser mounted in an automobile, tube 11 may sometimes become damaged and cause leakage of the heat exchanging medium when a stone, or the like, hits the tube 11 while the 5 automobile is moving.

BRIEF SUMMARY OF THE INVENTION

Two objects of the present invention are to provide both protection of the tube body against a stone or the like which hits the tube, and an excellent heat exchanging performance IO by keeping a large contact area with a heat exchange medium.

According to one aspect of the present invention, the above-

referenced objects can be achieved for use in a vehicle by a heat exchanger tube extending in an axial direction that has an end. The end has a first and second appendage attached to 15 it, such that, the first appendage and the second appendage are spaced from one another and the second appendage does not form an enclosed space with the first appendage.

According to another aspect of the present invention, the abovereferenced objects can be achieved for use in an 20 automotive air conditioner by a heat exchanger tube extending in an axial direction that has an end. The end has a first and second appendage attached to it, such that, the first appendage and the second appendage are spaced from one another and the second appendage does not form an enclosed 25 space with the first appendage.

Each of the above aspects of the present invention protects the tube's body from being damaged by the use of the nose tip-appendage. So that when an object, such as a stone, hits the tube, the nose-tip-appendage would collapse, absorbing 30 the energy of the incoming object. Furthermore, although the 3306p4 03 Hay 200Z

3 - present invention may be used in an automotive air conditioner, the present invention may also be used in a radiator oil cooler and, as stated above, the present invention may also be use in a residential heat exchanger.

5 Additional aspects and advantages of the present invention will become apparent from the following description and the

appended claims when considered with the accompanying drawing. BRIEF DESCRIPTION OF THE DRAWINGS

10 Fig. 1 shows a cross-sectional view of a known heat exchanger tube; Fig. 2A shows a cross-sectional view of a first embodiment of a heat exchanger according to the present invention; 15 Fig. 2B shows an enlarged cross-sectional view of the heat exchanger tube of Fig. 2A; Fig. 3 shows a cross-sectional view of a second embodiment of the heat exchanger tubed Fig. 4 shows a cross-sectional view of a third 20 embodiment of a heat exchanger tube according to the present invention; Fig. 5 shows an alternate configuration of the heat exchanger tube of Fig. 4, according to the present invention; 25 Fig. 6 shows front view of an embodiment a heat exchanger that includes one of the heat exchanger tubes of Figs. 2-5 according to the present invention; 3306p4 03 May 2002

- 4 Fig. 7A shows an embodiment of an automobile with a heat exchanger having one of the heat exchanger tubes of Figs. 2-5 according to the present invention; and Fig. 7B shows a residential home with an air conditioner 5 having one of the heat exchanger tubes of Figs. 2-5 according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 6 shows a heat exchanger of a so-called multi-flow type that includes a p arality of multi-bored flat tubes 1 each 10 having a certain length, fins 2 interposed between the tubes 1, and a pair of hollow headcr.s 3 to which the ends of the tubes 1 are connected. Each header 3 is divided by a partition 4. In operation, medium flows into the right hand header 3 through an inlet 5 connected to the upper portion of 15 the header, passes through the left hand header 3 through an outlet 6 connected to the lower portion of the header 3.

Fig. 2A shows an embodiment of a heat exchanger tube 20 or used in a vehicle. The heat exchanger tube 20 is an aluminum extruded article. As shown in Figs. 2A and 2B the heat 20 exchanger tube 20 extends in an axial direction and has nose ends 21. The typical length L of the heat exchanger tube 20 is designed to be in the range of 10.0 mm to 25.0 mm. A peripheral wall 22 is formed to have an elongated circular cross- sectional shape. A plurality of divisional walls 23 25 are provided in the heat exchanger tube 20 to form a plurality of compartments 24, 24a arranged in the axial direction of the heat exchanger tube 20. The divisional walls 23 connect flat wall portions 25 of the peripheral walls 22 with each other at a certain distance. The 30 thickness tl of divisional walls 23 can be designed to be in 3306p4 03 May 2002

- 5 the range of 0.15 mm to 0.45 mm while the thickness t2 of the flat wall portions 25 is designed to be in the range of 0.27 mm to 0..60 mm.

The inner surface of each of the outermost compartments 24a 5 is formed to be a circumferentially smooth curved shape in cross-section. In this embodiment, each compartment 24a is formed to have a rounded, or semicircular, inner surface at the outermost compartment side and a rectangle at the other side. The width cw of compartment 24a is typically from 0.30 10 mm to 3.0 mm. The height ch of compartment 24a is typical y from 0.6 mm to 3.5 mm. However, the compartment 24a may be formed to be an elongated circular cross-sectional shape, an elliptical shape or a perfect circular shape.

The plurality of inner compartments 24 are typically formed 15 to be rectangular in shape in cross-section. The width w of an inner compartment 24 is typically designed to be 1.4 ma;.

However, the inner compartments 24 are not constrained to be rectangular in shape in cross-section. The inner compartments 24 can be designed to have a triangular, a 20 trapezoidal, circular, or a star shape. A particular advantage of the present invention, in any embodiment, is that design of a major portion of the heat exchanger tube 20 is irrelevant as described below.

Attached to each of the nose ends 21 are appendages 26a, 26b.

25 Each of the appendages 26a, 26b are spaced from one another such that appendage 26a and appendage 26b do not form an enclosed space with one another. In this embodiment, each of the appendages 26a, 26b are substantially straight and are integrally formed from the flat wall portions 25. The 30 appendages 26a, 26b are also substantially parallel to each other. The thickness t3 of each of the appendages 26a, 26b 3306p4 03 May 2002

6 - is designed to be from 0.2 mm to 0.5 mm. While the thickness t4 of each of the nose ends 21 is typically in the range of 0.30 mm to 0.65 mm. Each of the appendages 26a, 26b extends 0.5 mm from nose ends 21. The height h, as measured from the 5 top of appendage 26a to the bottom of appendage 26b is designed to be 2.01 + 0.04 mm.

When the above-mentioned heat exchanger tube 2 0 is used in a condenser for an automobile air conditioner, the heat exchanger tube 20 may be hi t by an object, such as a stoic-, 10 that is passed through a radiator gr_ll of the automobile In this case, however, the appendages 26a 26b prevent the nose ends 21 fr em being damaged because typi -ally the appendages 26a/ 26. on the windward side of the he at exchanger would be hit first and collapse, absorbing the 1 energy of the incorm nor s:one, therefore, protecting heat exchanger tube 20.

Fig. 3 shows another embodiment of heat exchanger tube 20.

In this embodiment, the straight appendages 26a, 26b of Fig. 2A have been replaced by appendages 31.

20 Appendages 31 are attached to the center of nose ends 21. In this embodiment, appendages 31 are substantially straight and are integrally formed from the nose ends 21. Appendages 31 extend 0.5 mm from She tip of nose ends 21 and typically have a thickness t5 of 0.44 rnIn.

25 When the above-mentioned heat exchanger tube 20 is used in a condenser for an automobile air conditioner, the heat exchanger tube 20 may be hit by an object, such as a stone, that is passed through a radiator grill of the automobile.

In this case, however, the appendages 31 prevent the nose 30 ends 21 from being damaged because typically the appendage 31 3306p4 03 Hay 2002

- 7 on the windward side of the heat exchanger would be hit first and collapse, absorbing the energy of the incoming object, therefore, protecting heat exchanger tube 20.

Fig. 4 shows another embodiment of heat exchanger tube 20, 5 according to the present invention. In this embodiment, the straight appendages 26a, 26b of Fig. 2A have been replaced by appendages 41a, 41b, respectively.

Appendages 41a, 41b are attached to nose ends 21. Each Of the appendages 41a, 41b are spaced from one another such that 10 appendage 41a and appendage 4lb do not to Em an enclosed space with one another. In this embodiment, each of the appendages 41a, 4'b are curved with a radius of curvature of typically between 0.6 and 1.5 and are integrally formed from the flat .. wall portions 25. The appendages 41a, 41b also face each 15 other and end in a point. Each of the appendages 41a, 41b extend 0.5 rat from nose ends 21. The space S between each appendage 41a, 91b is preferably 1.0 mm.

When the above-mentioned heat exchanger tube 2 0 is used in a condenser for an automobile air conditioner, the heat 20 exchanger tube 20 may be hit by an object, such as a stone, that is passed through a radiator grill of the automobile.

In this case, however, the appendages 41a, 41b prevent the nose ends;21 from being damaged because typically the appendages 41a, 41b on the windward side of the heat 25 exchanger would be hit first and collapse, absorbing the energy of the incoming object, therefore, protecting heat exchanger tube 20. This embodiment of the present invention provides the superior protection for heat exchanger tube 20 because of the size of space S. stones greater than or equal 30 to 1.0 mrn cannot damage the heat exchanger tube 20.

3306p4 03 May 2002

- 8 Fig. 5 shows an alternate configuration of the embodiment as shown in Fig. 4 of heat exchanger tube 20, according to the present invention. In this embodiment, the straight appendages 26a, 26b of Fig. 2A have been replaced by 5 appendages 51a, 5lb.

Appendages 51a, 51b are attached to nose ends 21. Each of the appendages 51a, 51b are spaces from one another such that appendage 51a and appendage 51b do not form an enclosed space with one another. In this embodiment, each of the appendages 10 51a, 51b are curved with a radius of curvature of typically between 0.6 and 1.5 and are integrally formed from the flat wall portions 25. The appendages 51a, 51b also face each other and end in a flat part 52. Each of the appendages 51a, 541b extend 0.5 mm from nose ends 21. The space S between 15 each appendage Ala, 51b is preferably 0.79 mm.

When the above-mentioned heat exchanger tube 20 is used in a condenser for an automobile air conditioner, the heat exchanger tube 20 may be hit by an object, such as a stone, that is passed through a radiator grill of the automobile.

20 In this case, however, the appendages 41a, 41b prevent the nose ends 21 from being damaged because typically the appendages 41a, 91b on the windward side of the heat exchanger would be hit first and collapse, absorbing the energy of the incoming object, therefore, protecting heat 25 exchanger tube 20. This embodiment of the present invention provides the maximum protection for heat exchanger tube 20 because of the size of space S. stones greater than or equal to 0.79 mm cannot damage the heat exchanger tube 20.

As schematically shown in Fig. 7A, the heat exchanger tubes 30 of Figs. 25 and the heat exchanger 7 of Fig. 6 can be installed in an automobile 70, where the heat exchanger 7 is 3306p4 03 May 200Z

_ 9 part of the cooling system and/or air conditioning system of the automobile. In addition, the heat exchanger tubes of Figs. 2-5 and heat exchanger 7 of Fig. 6 can be installed in an air conditioning unit positioned within a residence 71 of 5 Fig. 7B.

The foregoing detailed description is merely illustrative of

several physical embodiments of the invention. Physical variations of the invention, not fully described in the specification, may be encompassed within the purview of the

10 claims. Accordir.gly, any narrower description of the

elements in the specification should be used for general

guidance, rather than to unduly restrict any broader descriptions of the elements in the following claims.

3306p4 03 May Z002

Claims

1. A heat exchanger tube for use in a vehicle, comprising: a tube extending in an axial direction and comprising an 5 end; a first appendage attached to said end; and a second appendage attached to said end; wherein said first appendage and said second appendage are spaced from one another and said second appendage 10 does not form an enclosed space with said first appendage.

2. A heat exchanger tube according to claim 1, wherein said first appendage is curved.

3. A heat exchanger tube according to claim 2, wherein said 15 second appendage is curved.

4. A heat exchanger tube according to claim 3, wherein said first and second appendages face each other.

5. A heat exchanger tube according to claim 1, wherein said first appendage is straight.

20

6. A heat exchanger tube according to claim 5, wherein said second appendage is straight.

7. A heat exchanger tube according to claim 6, wherein said first and second appendages are substantially parallel to one other. 25

8. A heat exchanger tube according to claim 1 wherein said tube further comprises a second end; a third appendage attached to said second end; 3306p4 03 May ZOOZ

- 11 a fourth appendage attached to said second end; and wherein said third appendage and said fourth appendage are spaced from one another and said fourth appendage does not form an enclosed space with said third 5 appendage.

9. A heat exchanger tube according to claim 8, wherein said third appendage is curved.

10. A heat exchanger tube according to claim 9, wherein said fourth appendage is curved.

10

11. A heat exchanger tube according to claim 10, wherein said third and fourth appendages face each other.

12. A heat exchanger tube according to claim 8, wherein said third appendage is straight.

13. A heat exchanger tube according to claim 12, wherein 15 said fourth appendage is straight.

14. The heat exchanger tube of claim 13, wherein said third and fourth appendages are substantially parallel to one other.

15. A heat exchanger system, comprising: 20 a condenser; a tube extending in an axial direction and comprising an end; side tube disposed adjacently to said condenser; a first appendage attached to said end; and 25 a second appendage attached to said end; wherein said first appendage and said second appendage are spaced from one another and said second appendage does not form an enclosed space with said first appendage. 3306p4 03 May 2002

- 12

16. A heat exchanger system according to claim 15, wherein said first appendage is curved.

17. A heat exchanger system according to claim 16, wherein said second appendage is curved.

5

18. A heat exchanger system according to claim 17, wherein said first and second appendages face each other.

19. A heat exchanger system according to claim 15, wherein said first appendage is straight.

20. A heat exchanger system according to claim 19, wherein 10 said second appendage is straight.

21. A heat exchanger system according to claim 20, wherein said first and second appendages are substantially parallel to one other.

22. A heat exchanger system according to claim 15, wherein 15 said condenser is positioned within an automotive.

23. A heat exchanger system according to claim 15, wherein said condenser is a residential condenser.

24. A heat exchanger system according to claim 15, wherein said condenser is a radiator oil cooler.

20

25. A heat exchanger system according to claim 15 wherein said tube further comprises a second end; a third appendage attached to said second end; a fourth appendage attached to said second end; and 25 wherein said third appendage and said fourth appendage are spaced from one another and said fourth appendage does not form an enclosed space with said third appendage. 3306pq 03 May 2002

- 13

26. A heat exchanger system according to claim 25, wherein said third appendage is curved.

27. A heat exchanger system according to claim 26, wherein said fourth appendage is curved.

5

28. A heat exchanger system according to claim 27, wherein said third and fourth appendages face each other.

29. A heat exchanger system according to claim 25, wherein said third appendage is straight.

30. A heat exchanger system according to claim 30, wherein 10 said fourth appendage is straight.

31. A heat exchanger system according to claim 30, wherein said third and fourth appendages are substantially parallel to one other.

32. A heat exchanger tube substantially as herein described, 15 with reference to the accompanying drawings.

33. A heat exchanger system substantially as herein described, with reference to the accompanying drawings.

3306p4 03 May Z002