Heat Exchanger Having Stand-Offs to Maintain Fin Spacing

Abstract

A fin for a heat exchanger that includes a fin body formed from a sheet of material; a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; and at least one stand-off attached to the fin body along the elongated central portion of the opening, wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening.

Description

FIELD

[0001] The present disclosure relates to a heat exchanger having stand-offs to maintain fin spacing.BACKGROUND

[0002] This section provides background information related to the present disclosure which is not necessarily prior art.SUMMARY

[0003] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

[0004] According to a first aspect of the present disclosure, there is provided a fin for a heat exchanger that includes a fin body formed from a sheet of material; a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; and at least one stand-off attached to the fin body along the elongated central portion of the opening, wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening.

[0005] According to the first aspect, the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

[0006] According to the first aspect, the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

[0007] According to the first aspect, the footing includes a curved profile in a shape of a semi-circle.

[0008] According to the first aspect, the at least one stand-off has a length that is about equal to a length of the elongated central opening.

[0009] According to the first aspect, the leg includes a plurality of apertures formed therein.

[0010] According to the first aspect, each of the rounded end portions may include a collar extending outward from the fin body.

[0011] According to the first aspect, the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

[0012] According to the first aspect, each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

[0013] According to a second aspect of the present disclosure, there is provided a heat exchanger that includes a plurality of the fins according to the first aspect; and a tube section mated with the plurality of openings.

[0014] According to the second aspect, a fin density of the heat exchanger is greater than twelve fins per inch.

[0015] According to a third aspect of the present disclosure, there is provided a heat exchanger that includes a plurality of fins that are spaced apart from each other; and a serpentine tube section that is mated with the plurality of fins, wherein each of the fins includes a fin body formed from a sheet of material; a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; and at least one stand-off attached to the fin body along the elongated central portion of the opening, wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening, and wherein the footing is configured to abut an adjacent fin and maintain a spacing between the fin body and the adjacent fin.

[0016] According to the third aspect, the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

[0017] According to the third aspect, the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

[0018] According to the third aspect, the footing includes a curved profile in a shape of a semi-circle.

[0019] According to the third aspect, the at least one stand-off has a length that is about equal to a length of the elongated central opening.

[0020] According to the third aspect, the leg includes a plurality of apertures formed therein.

[0021] According to the third aspect, each of the rounded end portions may include a collar extending outward from the fin body.

[0022] According to the third aspect, the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

[0023] According to the third aspect, each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

[0024] Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.DRAWINGS

[0025] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0026] FIG. 1 is an isometric perspective view of a conventional heat exchanger;

[0027] FIG. 2 is a front perspective view of a fin of the conventional heat exchanger illustrated in FIG. 1;

[0028] FIG. 3 is an isometric perspective view of a tube section of the conventional heat exchanger illustrated in FIG. 1;

[0029] FIG. 4 is an isometric perspective view of a collar of an opening of the fin illustrated in FIG. 3;

[0030] FIG. 5 is a side perspective view of a fin bank used to assemble the conventional heat exchanger illustrated in FIG. 1;

[0031] FIG. 6 is an isometric perspective view of a fin according to a principle of the present disclosure having a plurality of openings that include stand-offs to maintain spacing between adjacent fins;

[0032] FIG. 7 is an isometric perspective view of an opening of the fin illustrated in FIG. 6 having the stand-offs;

[0033] FIG. 8 is an isometric perspective view of one of the stand-offs illustrated in FIG. 7;

[0034] FIG. 9 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0035] FIG. 10 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0036] FIG. 11 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0037] FIG. 12 is an isometric perspective view of another example stand-off according to the present disclosure; and

[0038] FIG. 13 is an expanded isometric perspective view of the fin illustrated in FIG. 6, showing fluid flow enhancement features of the fin in greater detail.

[0039] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.DETAILED DESCRIPTION

[0040] Example embodiments will now be described more fully with reference to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0041] FIG. 1 illustrates an example conventional heat exchanger 10 having a plurality of heat exchanger fins 12 and a tube section 14. Tube section 14 can carry a first fluid or refrigerant, and as the first fluid or refrigerant passes through the tube section, the first fluid or refrigerant will exchange heat with a second fluid (e.g., air) that is passing through heat exchanger 10 (i.e., between fins 12 and over exterior surfaces of tube section 14). The thermal connection between heat exchanger fins 12 and tube section 14 enhances heat exchange between the first and second fluids.

[0042] As best shown in FIG. 2, each heat exchanger fin 12 has a plurality of openings 16 that are each configured and adapted to allow tube passes 18 of tube section 14 to pass therethrough. Fins 12 have a height H and a width W. Openings 16 may be arranged in a plurality of columns 20 and form a plurality of rows 22, that may each be spaced apart. Each fin 12 can be produced with any number of columns 20 and rows 22 of openings 16. The columns 24 may be substantially parallel to side edges 24 of fin 12 and extend from a top edge 26 to a bottom edge 28 of fin 12. Rows 22 may be substantially parallel to top and bottom edges 26, 28 and extend between side edges 24.

[0043] Referring now to FIG. 3, tube section 14 may include a plurality of straight segments 30 and a plurality of connecting segments 32. Each connecting segment 32 interconnects two straight segments 30 so that all of the straight segments 30 are interconnected and form the tube section 14 for use in the heat exchanger 10. The tube section 14 has at least one internal passageway (not shown) that allows the first fluid to flow through the tube section 14.

[0044] Tube section 14 may have a plurality of horizontal and vertical tube passes 18. A tube pass 18 is defined as the part of the tube section 14 that passes through a common (same) opening 16 in a fin 12. The tube section 14 will be configured for the specific application in which the heat exchanger 10 is desired to be used. That is, the number of vertical and horizontal tube passes 18 will vary depending upon the application in which the heat exchanger 10 formed from the tube section 14 is to be used. The tube section 14 may be configured with the tube passes 18 canted so that the heat exchanger 10 formed from the tube portion 30 efficiently transfers heat.

[0045] Each tube pass 18 may include a pair 40 of straight segments 30 which pass through all or a portion of the fins 12 on the heat exchanger 10. The two straight segments 30 are interconnected by a connecting segment 32. The straight segments 30 and the connecting segments 32 are formed into a sinuous or serpentine tube section 14, as is known in the art, to be used in the heat exchanger 10. Preferably, each straight segment 30 that forms a pair 40 of straight segments are parallel to one another. Even more preferably, all the straight segments 30 that comprise tube passes 18 are generally parallel. A single straight segment 30 could also pass through all or a portion of each fin 12 on the heat exchanger 10.

[0046] The tube section 14 is configured so that adjacent horizontal tube passes 18 are uniformly spaced apart and adjacent vertical tube passes 18 are uniformly spaced apart. Preferably, the spacing between adjacent horizontal tube passes 18 is generally the same as the spacing between adjacent vertical tube passes 18.

[0047] The tube section 14 can be made in a variety of manners. For example, tube section 14 can be made by bending a piece of continuous tubing 42 into the desired configuration. Alternatively, the tube section 14 can be formed by connecting independent straight segments 30 with independent connecting segments 32. That is, the tube section 14 can be assembled from a plurality of discreet components. The connecting segments 32 can be connected to the straight segments 30 by brazing, adhesives, or other means known in the art. The connecting segments 32, regardless of being discrete components or part of the tube, may be slightly flattened in a rectangular die (not shown) to facilitate insertion through openings 16 in fin 12.

[0048] Again referring to FIG. 2, it can be seen that the openings 16 in the fins 12 are configured to allow a tube pass 18 to pass therethrough. That is, the openings 16 are configured to allow a pair 40 of straight segments 30 and a connecting segment 32 to pass through the opening 16. The openings 16 are comprised of end portions 44 connected by a central portion 46. The end portions 44 are rounded and substantially complementary to the straight segments 30 that make up the tube section 14. End portions 44 may have a collar 48 (best seen in FIG. 4) that contacts straight segments 30, where collar 48 may have a flared end 49. End portions 44 may have a radius that is slightly less than a radius of the straight segments 30 to allow a press-fit connection with good surface contact between straight segments 30 and fins 12. The central portion 46 connects the end portions 44 and allows the connecting segment 32 attached to the pair of straight segments 30 to pass therethrough so that a fin 12 having the openings 16 can be positioned on a tube section 14 with each tube pass 18 passing through different openings 16 to form a heat exchanger 10. In the illustrated embodiment, the end portions 44 and the intermediate portion 46 are configured to form a “dog-bone” shape, as is known in the art. The openings 16 may be canted relative to the height H and width W. The tube section 14 is configured so that the tube passes 18 are also canted and are complementary to the canting of the openings 16.

[0049] To assemble heat exchanger 10, the desired number of fins 12 are formed and arranged in a fin bank 50, as shown in FIG. 5. The fin bank 50 and / or tube section 14 are aligned with one another and moved relative to one another so that tube passes 18 pass through openings 16 in fins 12 of fin bank 50, as is known in the art. The fins 12 can be secured to the tube section 14, by a variety of methods. Preferably the fins 12 are attached to the tube section 14 by a mechanical or interference fit. The openings 16 can be configured so that the end portions 46 and collar 48 deform slightly as a result of the tube passes 18 extending through the openings 16. The deformation of the end portions 46 and collar 48 mechanically retain the fins 12 at desired locations on the tube section 14 and provide good surface contact between fins 12 and tube section 30. Alternatively, other methods of attaching the fins 12 to the desired location of the tube section 14, such as by brazing and / or adhesives, may be employed.

[0050] Fin bank 50 maintains a spacing between fins 12, and typically comes with a fin density limitation of less than twelve fins per inch. It should be understood, however, that with increasing governmental regulation of the HVAC and R (heating, ventilation, air conditioning, and refrigeration) market, particularly with respect to the types of refrigerants that can be used for the first fluid that passes through the tube section 14, it may be beneficial to increase the fin density of heat exchanger 10 to maintain the same or better heat exchange capability.

[0051] In addition, it should be understood that conventional methods to increase the fin density of heat exchanger 10 to greater than twelve fins per inch typically included using fins having self-stacking features such as the use of a collar 48 that entirely surrounds the rounded end portion 44. These types of fins, however, would not include the dog-bone shaped opening 16 that uses an elongated portion 46 between the rounded end portions 44, which can inhibit the flow of fluid (e.g., air) through the heat exchanger. Moreover, it should be understood that even if fin 12 included dog-bone shaped openings 16 having a collar 48 that surrounded a portion of the rounded end portions 44 like that shown in FIG. 4, the use of a collar 48 having a flared end 49 may not be not feasible because collar 48 does not entirely surround the rounded end portion 44 and, as a result, may lose its strength and collapse when attempting to use a fin density greater than twelve fins per inch. Even if collar 48 does not collapse, there remains a risk that the collar 48 having a flared end 49 may tear or pull away from tube section 14 such that it loses thermal contact therewith such that heat exchange between the first fluid within tube section 14 and the second fluid (e.g., air) passing through heat exchanger 10 cannot be enhanced by fins 12.

[0052] With the above in mind, the present disclosure provides an improved heat exchanger 10 having a modified fin 52, which is shown in FIG. 6. Features common between the fins 12 described above and the fin 52 according to the present disclosure will share common reference numbers. Fin 52 includes a fin body 54 formed of a sheet of metal material (e.g., aluminum) having a plurality of openings 16 that have the characteristic “dog bone” shape described above. That is, openings 16 include a pair of rounded end portions 44 having a collar 48 that are connected by an elongated central portion 46. Notably, collar 48 does not include a flared end 49 because, as noted above, such a feature may collapse or pull away from the tube section 14 and reduce heat exchange capability. To offset the lack of flared end 49, fins 52 include at least one support feature or stand-off 56 associated with each opening 16 that extends outward from fin body 54, is provided along central portion 46, and is best shown in FIGS. 7 and 8.

[0053] Stand-off 56 provides structural rigidity to fins 50 to maintain a proper spacing between adjacent fins 50, as well as avoid buckling of fins 50 while a force is being applied to the fin bank 50 when tube section 14 is being inserted into the openings 16 to form heat exchanger 10. As shown in FIGS. 6-8, stand-off 56 includes a leg 58, which is a first planar member 59 having a proximal end 60 attached to fin body 54 and a distal end 62 positioned away from fin body 54. A footing 64, which is a second planar member 65 that is unitary with distal end 62 of leg 58, extends outward from leg 58 at an angle Φ that may be about 90 degrees (i.e., orthogonally) in a direction away from central portion 46. While the angle Φ being about 90 degrees is preferable, it should be understood that the angle Φ between footing 64 and distal end 62 of leg 58 may lie in the range of about 80 degrees to about 120 degrees, without departing from the scope of the present disclosure.

[0054] As best shown in FIG. 8, a length L1 of proximal end 60 may be greater than a length L2, wherein length L2 is a length of each of distal end 62 of leg 58 and footing 64. Proximal end 60 having a greater length L1 in comparison to distal end 62 and footing 64 provides leg 58 with increased rigidity to avoid buckling when footing 64 of stand-off 56 is abutted against an adjacent fin 50. A chamfered section 66 is positioned between proximal end 60 and distal end 62, which enables length L1 to be greater than length L2. It should be understood, however, that chamfered section 66 may omitted such that L1 may be equal to L2. In any event, in the embodiment illustrated in FIGS. length L1 may be in the range of 5 mm to 10 mm, and length L2 may be in the range of 4 mm to 8 mm. A height H1 of leg 58 may lie in the range of about 0.045 inches (˜1.143 mm) (i.e., such that heat exchanger can have twenty-two fins per inch) to 0.083 inches (˜2.108mm) (i.e., such that heat exchanger can have twelve fins per inch).

[0055] Footing 64, as noted above, may have a length L2 that lies in the range of 4 mm to 8 mm. Footing 64 also has a width W1 that may lie in the range of 2.5 mm to 4.5 mm. Width W1 provides footing 64 with sufficient rigidity to maintain the desired spacing between fin 50 and an adjacent fin 50, while avoiding buckling while a force is being applied to the fin bank 50 when tube section 14 is being inserted into the openings 16 to form heat exchanger 10.

[0056] While the above ranges for lengths L1, L2 and width W1 are preferable, it should be understood that lengths L1, L2 and width W1 are variable. That is, lengths L1, L2 may be greater as shown in FIG. 9 or lesser as shown in FIG. 10. In FIG. 9, the lengths L1 and L2 may be up to three times greater than that described relative to FIG. 7. In FIG. 10, the lengths L1 and L2 may be about half to three-quarters than that described relative to FIG. 7. In either embodiment, width W1 may be about the same, may be greater, or may be lesser that that described above relative to FIG. 7.

[0057] In the embodiment shown in FIGS. 7, 9, and 10 each opening 16 has a pair of stand-offs 56, with one stand-off 56 being positioned at a first end 68 at a first edge 69 of central portion 46 of opening 16 proximate one of the rounded end portions 44 and another stand-off 56 being positioned at an opposite second end 70 at an opposite second edge 71 of central portion 46 of opening 16 proximate the other rounded end portion 44. It should be understood, however, that only a single stand-off 56 is necessary. If only a single stand-off 56 is utilized, however, the lengths L1 and L2 should be much greater than the lengths L1 and L2 described relative to FIG. 7. Indeed, referring to FIG. 11, a single stand-off 56 illustrated having a length L1 that extends substantially an entire length L3 of central portion 46.

[0058] In addition, when stand-offs 56 that are smaller in size are used (see, e.g., FIG. 10), it should be understood that a greater number of stand-offs 56 (e.g., four) may be utilized, with a pair of the stand-offs 56 provided on the first edge 69 and a pair of the stand-offs 56 provided on the second edge 71.

[0059] In each of the above-described embodiments (i.e., FIGS. 7 and 9-11), the footing 64 is described as being composed of a second planar member 65. It should be understood, however, that footing 64 is not necessarily planar. Indeed, as shown in FIG. 12, footing 64 may have an arcuate or curved profile 72. The amount of curvature is variable, but in general the curved profile 72 may define a semi-circle. It should be understood, however, that to provide additional strength to footing 64, the curved profile 72 may define approximately a full circle where a terminal end 74 is curled back to be located in contact or directly proximate leg 58, if desired.

[0060] The distribution of the flow of the second fluid (e.g., air) through heat exchanger 10 may be influenced by the stand-offs 56. In this regard, if the stand-offs are too large, the stand-offs may create a maldistribution that reduces the amount of the second fluid reaching the exterior surface of tube section 14. Thus, it is preferable that the stand-offs of each opening 16 be separated by a gap 76, as shown in FIGS. 6, 7, 9, and 10. In the event that the configuration illustrated in FIG. 11 is selected and only a single stand-off 56 is associated with each opening 16, it should be understood that leg 58 may be modified to include apertures 78 to permit the second fluid to flow therethrough, and attempt to limit any maldistribution. The number, size, and shape (e.g., square, rectangular, circulate, triangular, oval, etc.) of apertures 78 is variable, but should be selected so as to not sacrifice the structural integrity (e.g., rigidity) of the stand-off 56 so that stand-off 56 can maintain the proper spacing between adjacent fins 50.

[0061] In addition, again referring to FIG. 6 as well as FIG. 13, it should be understood that fin 52 may have fluid flow enhancement features 80 at locations of fin body 54 positioned between openings 16. Enhancement features 80 may include an elongated slat 82 having a first portion 84 connected to fin body 54 and an opposite second portion 86 connected to fin body 54 that is punched from fin body 54 during manufacture of fin 52, leaving an elongated opening 88 in fin body 54 beneath slat 82. A length of slat 82 and opening 88 is variable, as shown in FIG. 13 where a first slate 82a is shorter than a second slat 82b, which is shorter than a third slat 82c. It should be understood, however, that each slat 82 may have the same length, if desired. As the second fluid (e.g., air) flows over fin 52, the slats 82 and openings 88 will create a turbulent flow that may enhance heat exchange between the first fluid carried by tube section 14 and the second fluid flowing through heat exchanger 10.

[0062] Fins 52 may be formed by using a stamping apparatus (not shown) that is configured punch openings 16, form stand-offs 56, collar 48, and enhancement features 80. By forming stand-offs 56 along central portion 46, a portion of the material of fin body 54 that is typically lost as scrap can be used to form stand-offs 56, while leaving the material between adjacent openings 16 available to form enhancement features 80. Thus, in addition to providing fins 52 with increased rigidity when abutted against an adjacent 52 in fin bank 50, which permits a greater fin density per inch, the use of stand-offs 56 also permits more material to be utilized and reduces waste. This, in turn, reduces material costs associated with manufacturing fins 52 and heat exchanger 10.

[0063] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Examples

Embodiment Construction

[0040]Example embodiments will now be described more fully with reference to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0041]FIG. 1 illustrates an example conventional heat exchanger 10 having a plurality of heat exchanger fins 12 and a tube section 14. Tube section 14 can carry a first fluid or refrigerant, and ...

FIELD

[0001] The present disclosure relates to a heat exchanger having stand-offs to maintain fin spacing.BACKGROUND

[0002] This section provides background information related to the present disclosure which is not necessarily prior art.SUMMARY

[0003] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

[0004] According to a first aspect of the present disclosure, there is provided a fin for a heat exchanger that includes a fin body formed from a sheet of material; a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; and at least one stand-off attached to the fin body along the elongated central portion of the opening, wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening.

[0005] According to the first aspect, the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

[0006] According to the first aspect, the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

[0007] According to the first aspect, the footing includes a curved profile in a shape of a semi-circle.

[0008] According to the first aspect, the at least one stand-off has a length that is about equal to a length of the elongated central opening.

[0009] According to the first aspect, the leg includes a plurality of apertures formed therein.

[0010] According to the first aspect, each of the rounded end portions may include a collar extending outward from the fin body.

[0011] According to the first aspect, the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

[0012] According to the first aspect, each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

[0013] According to a second aspect of the present disclosure, there is provided a heat exchanger that includes a plurality of the fins according to the first aspect; and a tube section mated with the plurality of openings.

[0014] According to the second aspect, a fin density of the heat exchanger is greater than twelve fins per inch.

[0015] According to a third aspect of the present disclosure, there is provided a heat exchanger that includes a plurality of fins that are spaced apart from each other; and a serpentine tube section that is mated with the plurality of fins, wherein each of the fins includes a fin body formed from a sheet of material; a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; and at least one stand-off attached to the fin body along the elongated central portion of the opening, wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening, and wherein the footing is configured to abut an adjacent fin and maintain a spacing between the fin body and the adjacent fin.

[0016] According to the third aspect, the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

[0017] According to the third aspect, the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

[0018] According to the third aspect, the footing includes a curved profile in a shape of a semi-circle.

[0019] According to the third aspect, the at least one stand-off has a length that is about equal to a length of the elongated central opening.

[0020] According to the third aspect, the leg includes a plurality of apertures formed therein.

[0021] According to the third aspect, each of the rounded end portions may include a collar extending outward from the fin body.

[0022] According to the third aspect, the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

[0023] According to the third aspect, each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

[0024] Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.DRAWINGS

[0025] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0026] FIG. 1 is an isometric perspective view of a conventional heat exchanger;

[0027] FIG. 2 is a front perspective view of a fin of the conventional heat exchanger illustrated in FIG. 1;

[0028] FIG. 3 is an isometric perspective view of a tube section of the conventional heat exchanger illustrated in FIG. 1;

[0029] FIG. 4 is an isometric perspective view of a collar of an opening of the fin illustrated in FIG. 3;

[0030] FIG. 5 is a side perspective view of a fin bank used to assemble the conventional heat exchanger illustrated in FIG. 1;

[0031] FIG. 6 is an isometric perspective view of a fin according to a principle of the present disclosure having a plurality of openings that include stand-offs to maintain spacing between adjacent fins;

[0032] FIG. 7 is an isometric perspective view of an opening of the fin illustrated in FIG. 6 having the stand-offs;

[0033] FIG. 8 is an isometric perspective view of one of the stand-offs illustrated in FIG. 7;

[0034] FIG. 9 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0035] FIG. 10 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0036] FIG. 11 is an isometric perspective view of another example opening having another embodiment of the stand-offs;

[0037] FIG. 12 is an isometric perspective view of another example stand-off according to the present disclosure; and

[0038] FIG. 13 is an expanded isometric perspective view of the fin illustrated in FIG. 6, showing fluid flow enhancement features of the fin in greater detail.

[0039] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.DETAILED DESCRIPTION

[0040] Example embodiments will now be described more fully with reference to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0041] FIG. 1 illustrates an example conventional heat exchanger 10 having a plurality of heat exchanger fins 12 and a tube section 14. Tube section 14 can carry a first fluid or refrigerant, and as the first fluid or refrigerant passes through the tube section, the first fluid or refrigerant will exchange heat with a second fluid (e.g., air) that is passing through heat exchanger 10 (i.e., between fins 12 and over exterior surfaces of tube section 14). The thermal connection between heat exchanger fins 12 and tube section 14 enhances heat exchange between the first and second fluids.

[0042] As best shown in FIG. 2, each heat exchanger fin 12 has a plurality of openings 16 that are each configured and adapted to allow tube passes 18 of tube section 14 to pass therethrough. Fins 12 have a height H and a width W. Openings 16 may be arranged in a plurality of columns 20 and form a plurality of rows 22, that may each be spaced apart. Each fin 12 can be produced with any number of columns 20 and rows 22 of openings 16. The columns 24 may be substantially parallel to side edges 24 of fin 12 and extend from a top edge 26 to a bottom edge 28 of fin 12. Rows 22 may be substantially parallel to top and bottom edges 26, 28 and extend between side edges 24.

[0043] Referring now to FIG. 3, tube section 14 may include a plurality of straight segments 30 and a plurality of connecting segments 32. Each connecting segment 32 interconnects two straight segments 30 so that all of the straight segments 30 are interconnected and form the tube section 14 for use in the heat exchanger 10. The tube section 14 has at least one internal passageway (not shown) that allows the first fluid to flow through the tube section 14.

[0044] Tube section 14 may have a plurality of horizontal and vertical tube passes 18. A tube pass 18 is defined as the part of the tube section 14 that passes through a common (same) opening 16 in a fin 12. The tube section 14 will be configured for the specific application in which the heat exchanger 10 is desired to be used. That is, the number of vertical and horizontal tube passes 18 will vary depending upon the application in which the heat exchanger 10 formed from the tube section 14 is to be used. The tube section 14 may be configured with the tube passes 18 canted so that the heat exchanger 10 formed from the tube portion 30 efficiently transfers heat.

[0045] Each tube pass 18 may include a pair 40 of straight segments 30 which pass through all or a portion of the fins 12 on the heat exchanger 10. The two straight segments 30 are interconnected by a connecting segment 32. The straight segments 30 and the connecting segments 32 are formed into a sinuous or serpentine tube section 14, as is known in the art, to be used in the heat exchanger 10. Preferably, each straight segment 30 that forms a pair 40 of straight segments are parallel to one another. Even more preferably, all the straight segments 30 that comprise tube passes 18 are generally parallel. A single straight segment 30 could also pass through all or a portion of each fin 12 on the heat exchanger 10.

[0046] The tube section 14 is configured so that adjacent horizontal tube passes 18 are uniformly spaced apart and adjacent vertical tube passes 18 are uniformly spaced apart. Preferably, the spacing between adjacent horizontal tube passes 18 is generally the same as the spacing between adjacent vertical tube passes 18.

[0047] The tube section 14 can be made in a variety of manners. For example, tube section 14 can be made by bending a piece of continuous tubing 42 into the desired configuration. Alternatively, the tube section 14 can be formed by connecting independent straight segments 30 with independent connecting segments 32. That is, the tube section 14 can be assembled from a plurality of discreet components. The connecting segments 32 can be connected to the straight segments 30 by brazing, adhesives, or other means known in the art. The connecting segments 32, regardless of being discrete components or part of the tube, may be slightly flattened in a rectangular die (not shown) to facilitate insertion through openings 16 in fin 12.

[0048] Again referring to FIG. 2, it can be seen that the openings 16 in the fins 12 are configured to allow a tube pass 18 to pass therethrough. That is, the openings 16 are configured to allow a pair 40 of straight segments 30 and a connecting segment 32 to pass through the opening 16. The openings 16 are comprised of end portions 44 connected by a central portion 46. The end portions 44 are rounded and substantially complementary to the straight segments 30 that make up the tube section 14. End portions 44 may have a collar 48 (best seen in FIG. 4) that contacts straight segments 30, where collar 48 may have a flared end 49. End portions 44 may have a radius that is slightly less than a radius of the straight segments 30 to allow a press-fit connection with good surface contact between straight segments 30 and fins 12. The central portion 46 connects the end portions 44 and allows the connecting segment 32 attached to the pair of straight segments 30 to pass therethrough so that a fin 12 having the openings 16 can be positioned on a tube section 14 with each tube pass 18 passing through different openings 16 to form a heat exchanger 10. In the illustrated embodiment, the end portions 44 and the intermediate portion 46 are configured to form a “dog-bone” shape, as is known in the art. The openings 16 may be canted relative to the height H and width W. The tube section 14 is configured so that the tube passes 18 are also canted and are complementary to the canting of the openings 16.

[0049] To assemble heat exchanger 10, the desired number of fins 12 are formed and arranged in a fin bank 50, as shown in FIG. 5. The fin bank 50 and / or tube section 14 are aligned with one another and moved relative to one another so that tube passes 18 pass through openings 16 in fins 12 of fin bank 50, as is known in the art. The fins 12 can be secured to the tube section 14, by a variety of methods. Preferably the fins 12 are attached to the tube section 14 by a mechanical or interference fit. The openings 16 can be configured so that the end portions 46 and collar 48 deform slightly as a result of the tube passes 18 extending through the openings 16. The deformation of the end portions 46 and collar 48 mechanically retain the fins 12 at desired locations on the tube section 14 and provide good surface contact between fins 12 and tube section 30. Alternatively, other methods of attaching the fins 12 to the desired location of the tube section 14, such as by brazing and / or adhesives, may be employed.

[0050] Fin bank 50 maintains a spacing between fins 12, and typically comes with a fin density limitation of less than twelve fins per inch. It should be understood, however, that with increasing governmental regulation of the HVAC and R (heating, ventilation, air conditioning, and refrigeration) market, particularly with respect to the types of refrigerants that can be used for the first fluid that passes through the tube section 14, it may be beneficial to increase the fin density of heat exchanger 10 to maintain the same or better heat exchange capability.

[0051] In addition, it should be understood that conventional methods to increase the fin density of heat exchanger 10 to greater than twelve fins per inch typically included using fins having self-stacking features such as the use of a collar 48 that entirely surrounds the rounded end portion 44. These types of fins, however, would not include the dog-bone shaped opening 16 that uses an elongated portion 46 between the rounded end portions 44, which can inhibit the flow of fluid (e.g., air) through the heat exchanger. Moreover, it should be understood that even if fin 12 included dog-bone shaped openings 16 having a collar 48 that surrounded a portion of the rounded end portions 44 like that shown in FIG. 4, the use of a collar 48 having a flared end 49 may not be not feasible because collar 48 does not entirely surround the rounded end portion 44 and, as a result, may lose its strength and collapse when attempting to use a fin density greater than twelve fins per inch. Even if collar 48 does not collapse, there remains a risk that the collar 48 having a flared end 49 may tear or pull away from tube section 14 such that it loses thermal contact therewith such that heat exchange between the first fluid within tube section 14 and the second fluid (e.g., air) passing through heat exchanger 10 cannot be enhanced by fins 12.

[0052] With the above in mind, the present disclosure provides an improved heat exchanger 10 having a modified fin 52, which is shown in FIG. 6. Features common between the fins 12 described above and the fin 52 according to the present disclosure will share common reference numbers. Fin 52 includes a fin body 54 formed of a sheet of metal material (e.g., aluminum) having a plurality of openings 16 that have the characteristic “dog bone” shape described above. That is, openings 16 include a pair of rounded end portions 44 having a collar 48 that are connected by an elongated central portion 46. Notably, collar 48 does not include a flared end 49 because, as noted above, such a feature may collapse or pull away from the tube section 14 and reduce heat exchange capability. To offset the lack of flared end 49, fins 52 include at least one support feature or stand-off 56 associated with each opening 16 that extends outward from fin body 54, is provided along central portion 46, and is best shown in FIGS. 7 and 8.

[0053] Stand-off 56 provides structural rigidity to fins 50 to maintain a proper spacing between adjacent fins 50, as well as avoid buckling of fins 50 while a force is being applied to the fin bank 50 when tube section 14 is being inserted into the openings 16 to form heat exchanger 10. As shown in FIGS. 6-8, stand-off 56 includes a leg 58, which is a first planar member 59 having a proximal end 60 attached to fin body 54 and a distal end 62 positioned away from fin body 54. A footing 64, which is a second planar member 65 that is unitary with distal end 62 of leg 58, extends outward from leg 58 at an angle Φ that may be about 90 degrees (i.e., orthogonally) in a direction away from central portion 46. While the angle Φ being about 90 degrees is preferable, it should be understood that the angle Φ between footing 64 and distal end 62 of leg 58 may lie in the range of about 80 degrees to about 120 degrees, without departing from the scope of the present disclosure.

[0054] As best shown in FIG. 8, a length L1 of proximal end 60 may be greater than a length L2, wherein length L2 is a length of each of distal end 62 of leg 58 and footing 64. Proximal end 60 having a greater length L1 in comparison to distal end 62 and footing 64 provides leg 58 with increased rigidity to avoid buckling when footing 64 of stand-off 56 is abutted against an adjacent fin 50. A chamfered section 66 is positioned between proximal end 60 and distal end 62, which enables length L1 to be greater than length L2. It should be understood, however, that chamfered section 66 may omitted such that L1 may be equal to L2. In any event, in the embodiment illustrated in FIGS. length L1 may be in the range of 5 mm to 10 mm, and length L2 may be in the range of 4 mm to 8 mm. A height H1 of leg 58 may lie in the range of about 0.045 inches (˜1.143 mm) (i.e., such that heat exchanger can have twenty-two fins per inch) to 0.083 inches (˜2.108mm) (i.e., such that heat exchanger can have twelve fins per inch).

[0055] Footing 64, as noted above, may have a length L2 that lies in the range of 4 mm to 8 mm. Footing 64 also has a width W1 that may lie in the range of 2.5 mm to 4.5 mm. Width W1 provides footing 64 with sufficient rigidity to maintain the desired spacing between fin 50 and an adjacent fin 50, while avoiding buckling while a force is being applied to the fin bank 50 when tube section 14 is being inserted into the openings 16 to form heat exchanger 10.

[0056] While the above ranges for lengths L1, L2 and width W1 are preferable, it should be understood that lengths L1, L2 and width W1 are variable. That is, lengths L1, L2 may be greater as shown in FIG. 9 or lesser as shown in FIG. 10. In FIG. 9, the lengths L1 and L2 may be up to three times greater than that described relative to FIG. 7. In FIG. 10, the lengths L1 and L2 may be about half to three-quarters than that described relative to FIG. 7. In either embodiment, width W1 may be about the same, may be greater, or may be lesser that that described above relative to FIG. 7.

[0057] In the embodiment shown in FIGS. 7, 9, and 10 each opening 16 has a pair of stand-offs 56, with one stand-off 56 being positioned at a first end 68 at a first edge 69 of central portion 46 of opening 16 proximate one of the rounded end portions 44 and another stand-off 56 being positioned at an opposite second end 70 at an opposite second edge 71 of central portion 46 of opening 16 proximate the other rounded end portion 44. It should be understood, however, that only a single stand-off 56 is necessary. If only a single stand-off 56 is utilized, however, the lengths L1 and L2 should be much greater than the lengths L1 and L2 described relative to FIG. 7. Indeed, referring to FIG. 11, a single stand-off 56 illustrated having a length L1 that extends substantially an entire length L3 of central portion 46.

[0058] In addition, when stand-offs 56 that are smaller in size are used (see, e.g., FIG. 10), it should be understood that a greater number of stand-offs 56 (e.g., four) may be utilized, with a pair of the stand-offs 56 provided on the first edge 69 and a pair of the stand-offs 56 provided on the second edge 71.

[0059] In each of the above-described embodiments (i.e., FIGS. 7 and 9-11), the footing 64 is described as being composed of a second planar member 65. It should be understood, however, that footing 64 is not necessarily planar. Indeed, as shown in FIG. 12, footing 64 may have an arcuate or curved profile 72. The amount of curvature is variable, but in general the curved profile 72 may define a semi-circle. It should be understood, however, that to provide additional strength to footing 64, the curved profile 72 may define approximately a full circle where a terminal end 74 is curled back to be located in contact or directly proximate leg 58, if desired.

[0060] The distribution of the flow of the second fluid (e.g., air) through heat exchanger 10 may be influenced by the stand-offs 56. In this regard, if the stand-offs are too large, the stand-offs may create a maldistribution that reduces the amount of the second fluid reaching the exterior surface of tube section 14. Thus, it is preferable that the stand-offs of each opening 16 be separated by a gap 76, as shown in FIGS. 6, 7, 9, and 10. In the event that the configuration illustrated in FIG. 11 is selected and only a single stand-off 56 is associated with each opening 16, it should be understood that leg 58 may be modified to include apertures 78 to permit the second fluid to flow therethrough, and attempt to limit any maldistribution. The number, size, and shape (e.g., square, rectangular, circulate, triangular, oval, etc.) of apertures 78 is variable, but should be selected so as to not sacrifice the structural integrity (e.g., rigidity) of the stand-off 56 so that stand-off 56 can maintain the proper spacing between adjacent fins 50.

[0061] In addition, again referring to FIG. 6 as well as FIG. 13, it should be understood that fin 52 may have fluid flow enhancement features 80 at locations of fin body 54 positioned between openings 16. Enhancement features 80 may include an elongated slat 82 having a first portion 84 connected to fin body 54 and an opposite second portion 86 connected to fin body 54 that is punched from fin body 54 during manufacture of fin 52, leaving an elongated opening 88 in fin body 54 beneath slat 82. A length of slat 82 and opening 88 is variable, as shown in FIG. 13 where a first slate 82a is shorter than a second slat 82b, which is shorter than a third slat 82c. It should be understood, however, that each slat 82 may have the same length, if desired. As the second fluid (e.g., air) flows over fin 52, the slats 82 and openings 88 will create a turbulent flow that may enhance heat exchange between the first fluid carried by tube section 14 and the second fluid flowing through heat exchanger 10.

[0062] Fins 52 may be formed by using a stamping apparatus (not shown) that is configured punch openings 16, form stand-offs 56, collar 48, and enhancement features 80. By forming stand-offs 56 along central portion 46, a portion of the material of fin body 54 that is typically lost as scrap can be used to form stand-offs 56, while leaving the material between adjacent openings 16 available to form enhancement features 80. Thus, in addition to providing fins 52 with increased rigidity when abutted against an adjacent 52 in fin bank 50, which permits a greater fin density per inch, the use of stand-offs 56 also permits more material to be utilized and reduces waste. This, in turn, reduces material costs associated with manufacturing fins 52 and heat exchanger 10.

[0063] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Examples

Embodiment Construction

[0040]Example embodiments will now be described more fully with reference to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0041]FIG. 1 illustrates an example conventional heat exchanger 10 having a plurality of heat exchanger fins 12 and a tube section 14. Tube section 14 can carry a first fluid or refrigerant, and ...

Claims

1. A fin for a heat exchanger, comprising:a fin body formed from a sheet of material;a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; andat least one stand-off attached to the fin body along the elongated central portion of the opening,wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening.

2. The fin according to claim 1, wherein the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

3. The fin according to claim 2, wherein the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

4. The fin according to claim 1, wherein the footing includes a curved profile in a shape of a semi-circle.

5. The fin according to claim 1, wherein the at least one stand-off has a length that is about equal to a length of the elongated central opening.

6. The fin according to claim 5, wherein the leg includes a plurality of apertures formed therein.

7. The fin according to claim 1, wherein each of the rounded end portions includes a collar extending outward from the fin body.

8. The fin according to claim 1, wherein the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

9. The fin according to claim 8, wherein each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

10. A heat exchanger comprising:a plurality of the fins according to claim 1; anda tube section mated with the plurality of openings.

11. The heat exchanger according to claim 10, wherein a fin density of the heat exchanger is greater than twelve fins per inch.

12. A heat exchanger, comprising:a plurality of fins that are spaced apart from each other; anda serpentine tube section that is mated with the plurality of fins,wherein each of the fins includes:a fin body formed from a sheet of material;a plurality of openings formed in the fin body, each of the plurality of openings having a pair of rounded end portions connected by an elongated central portion; andat least one stand-off attached to the fin body along the elongated central portion of the opening,wherein the at least one stand-off includes a leg having a proximal end connected to and that extends outward from the fin body and a distal end, and the at least one stand-off includes a footing connected to the distal end of the leg that extends outward from the distal end in a direction away from the central portion of the opening, andwherein the footing is configured to abut an adjacent fin and maintain a spacing between the fin body and the adjacent fin.

13. The heat exchanger according to claim 12, wherein the at least one stand-off includes a first stand-off along a first end of the elongated central opening at a position proximate one of the pair of rounded end portions and a second stand-off along a second and opposite end of the elongated central opening a position proximate another of the pair of rounded end portions.

14. The heat exchanger according to claim 13, wherein the first stand-off is attached to a first edge of the elongated central opening and the second stand-off is attached to an opposite second edge of the elongated central opening.

15. The heat exchanger according to claim 12, wherein the footing includes a curved profile in a shape of a semi-circle.

16. The heat exchanger according to claim 12, wherein the at least one stand-off has a length that is about equal to a length of the elongated central opening.

17. The heat exchanger according to claim 16, wherein the leg includes a plurality of apertures formed therein.

18. The heat exchanger according to claim 12, wherein each of the rounded end portions includes a collar extending outward from the fin body.

19. The heat exchanger according to claim 12, wherein the fin body includes a plurality of fluid flow enhancement features positioned between the plurality of openings.

20. The heat exchanger according to claim 19, wherein each of the fluid flow enhancement features includes an elongated slat that is bent outward relative to the fin body.

Images