WO2010011452A2

WO2010011452A2 - Adapter for heat exchanger

Info

Publication number: WO2010011452A2
Application number: PCT/US2009/048101
Authority: WO
Inventors: Andrew E. Karl; Ron A. Wilson; Derek Leman
Original assignee: Carrier Corporation
Priority date: 2008-07-23
Filing date: 2009-06-22
Publication date: 2010-01-28
Also published as: WO2010011452A3; US20110073277A1

Abstract

A heat exchanger includes a first manifold, a second manifold and a plurality of tubes extending between the first manifold and the second manifold. An adapter is mounted to the first manifold, and the adapter includes a plurality of engagement features engageable by a forming machine to form the heat exchanger into a shape.

Description

ADAPTER FOR HEAT EXCHANGER

RELATED APPLICATIONS

This application claims priority to United States Provisional Patent Application Number 61/082,957, which was filed July 23, 2008.

BACKGROUND OF THE INVENTION

As shown in Figure 1, a prior art heat exchanger 36 of a refrigeration system includes tubes 38 extending between two header plates 40 and 42. A refrigerant flows though the tubes 38 and exchanges heat with air that flows over the tubes 38. Refrigerant flows in a first direction A through a tube 38. The refrigerant exits the tubes 38, flows through a u-shaped tube 44 (or hairpin tube), and then flows through another tube 38 in an opposing second direction B. During manufacture of the heat exchanger 36, the tubes 38 are bent or formed into a desired shape by a forming machine. The forming machine engages the u-shaped tubes 44 and bends or forms the tubes 38 to the desired shape.

A microchannel heat exchanger includes a plurality of flat tubes extending between two manifolds. The microchannel heat exchanger does not include header plates or u-shaped tubes. The manifolds at the ends of the tubes of the microchannel heat exchanger have a different structure than the header plates at the ends of the tubes of the prior art heat exchanger and do not include the u-shaped tubes that can be engaged by the forming machine.

In one prior heat exchanger described in United States Patent No. 5,964,281, an adapter is attached to the heat exchanger to create new inlet and outlet port locations to allow the heat exchanger to be employed in different environments. The adapter is attached to ends of the headers of the heat exchanger. The adapter is substantially perpendicular to the headers and substantially parallel to the plurality of tubes.

SUMMARY OF THE INVENTION

Another illustrative embodiment provides an adapter attachable to a manifold of a heat exchanger. The adapter includes a curved wall, a plurality of attachment members located on a first side of the curved wall, and a plurality of u-shaped members located on an opposing second side of the curved wall. The plurality of attachment members and the curved wall define a space to receive a manifold of a heat exchanger.

These and other features of the present invention will be best understood from the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The various features and advantages of the invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:

Figure 1 schematically illustrates a prior art heat exchanger; Figure 2 schematically illustrates a prior art refrigeration system; Figure 3 schematically illustrates a microchannel heat exchanger before the microchannel tubes are formed; Figure 4 schematically illustrates a forming machine engaging an adapter of the microchannel heat exchanger;

Figure 5 schematically illustrates a perspective view of the adapter; Figure 6 schematically illustrates an enlarged view of the adapter of Figure 5; Figure 7 schematically illustrates another perspective view of the adapter; Figure 8 schematically illustrates a perspective view of the adapter and a return manifold prior to attachment;

Figure 9 schematically illustrates a perspective view of the adapter attached to the return manifold;

Figure 10 schematically illustrates another perspective view of the adapter attached to the return manifold; Figure 11 schematically illustrates a perspective view of the microchannel heat exchanger after the microchannel tubes are formed;

Figure 12 schematically illustrates a perspective view of the microchannel heat exchanger mounted in a cabinet; and Figure 13 schematically illustrates a side view of the microchannel heat exchanger mounted to the cabinet.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Figure 2 schematically illustrates a refrigeration system 20 including a compressor 22, a first heat exchanger 24, an expansion device 26, and a second heat exchanger 28. Refrigerant circulates through the closed circuit refrigeration system 20.

When the refrigeration system 20 is operating in a cooling mode, the refrigerant exits the compressor 22 at a high pressure and a high enthalpy and flows through the first heat exchanger 24, which acts as a condenser. In the first heat exchanger 24, the refrigerant rejects heat to air and is condensed into a liquid that exits the first heat exchanger 24 at a low enthalpy and a high pressure. A fan 30 directs the air through the first heat exchanger 24. The cooled refrigerant then passes through the expansion device 26, expanding the refrigerant to a low pressure. After expansion, the refrigerant flows through the second heat exchanger 28, which acts as an evaporator. In the second heat exchanger 28, the refrigerant accepts heat from air, exiting the second heat exchanger 28 at a high enthalpy and a low pressure. A fan 32 blows air through the second heat exchanger 28. The refrigerant then flows to the compressor 22, completing the cycle.

When the refrigeration system 20 is operating in a heating mode, the flow of the refrigerant is reversed with a four-way valve 34. The first heat exchanger 24 accepts heat from the air and functions as an evaporator, and the second heat exchanger 28 rejects heat to the air and functions as a condenser.

Either or both of the heat exchangers 24 and 28 can be a microchannel heat exchanger 46. The microchannel heat exchanger 46 can be used, for example, with a microdevice, an automobile air conditioner, a residential system, or any type of system. For ease of reference, the microchannel heat exchanger can be referred to as a microchannel heat exchanger 46. Figure 3 illustrates the microchannel heat exchanger 46 before being formed. The microchannel heat exchanger 46 includes an inlet/outlet manifold 48, a return manifold 50, and a plurality of flat microchannel tubes 52 that extend between the manifolds 48 and 50. The manifolds 48 and 50 are substantially cylindrical and have a diameter Y. The microchannel tubes 52 are substantially parallel. Each microchannel tube 52 is a flat multi-port tube, and each port has a hydraulic diameter of less than 1 mm. A plurality of fins 140 are located between adjacent microchannel tubes 52 to increase heat transfer.

In one example, the refrigerant makes two passes through the microchannel heat exchanger 46 (referred to as a circuit). A pass is defined as one trip through the microchannel tubes 52 between the manifolds 48 and 50. However, the refrigerant can make any number of passes through the circuit. For example, the refrigerant can make only one pass or can make more than two passes through the microchannel heat exchanger 46. Although only one circuit is illustrated and described, the microchannel heat exchanger 46 can include multiple independent and separate refrigerant circuits. The refrigerant enters the microchannel heat exchanger 46 through an inlet tube

54 and is directed into an inlet section 56 of the inlet/outlet manifold 48. The refrigerant flows in a first direction A through a group microchannel tubes 52 and enters the return manifold 50. The return manifold 50 directs the refrigerant through another group microchannel tubes 52, and the refrigerant flows in an opposing second direction B and into an outlet section 58 of inlet/outlet manifold 48. The refrigerant exits the microchannel heat exchanger 46 through an outlet tube 60. The inlet section 56 and the outlet section 58 of the inlet/outlet manifold 48 are separated by a divider wall 62 to prevent fluid communication therebetween. As the refrigerant flows through the microchannel tubes 52, the refrigerant exchanges heat with air that flows over the microchannel tubes 52.

The microchannel heat exchanger 46 does not include the u-shaped tubes 44 of the prior art heat exchanger 36. An adapter 68 is attached to the return manifold 50 during assembly to simulate the configuration and structure of the prior art heat exchanger 36. As shown schematically in Figure 4, the microchannel heat exchanger 46 is formed or bent into a desired shape by a forming machine 64. The forming machine 64 includes a forming arm 66 that engages the adapter 68 to form or bend the microchannel heat exchanger 46 into a desired shape. The adapter 68 allows the microchannel heat exchanger 46 to simulate the structure and configuration of the prior art heat exchangers 36, allowing known forming machines 64 to be used. The forming machine 64 and its forming arm 66 can engage the adapter 68 to form or bend the microchannel heat exchanger 46 into the desired shape without requiring modification to the forming machine 64 or the forming arm 66.

Figures 5, 6 and 7 illustrate the adapter 68. The adapter 68 is a single, unitary component. The adapter 68 is attached to the return manifold 50 of the microchannel heat exchanger 46. In one example, the adapter 68 is made of injection molded plastic. The adapter 68 has a length X and includes a plurality of fasteners 70 (a plurality of attachment members). Each fastener 70 is spaced along the length X of the adapter 68 and includes a flexible first arm 74 and a flexible second arm 76. The adapter 68 includes a curved wall 72 having a first side 78 that faces the return manifold 50 and an opposing second side 80 that faces away from the return manifold 50. The arms 74 and 76 extend from the first side 78 of the curved wall 72 (shown in Figures 5 and 6).

As further shown in Figure 6, the first arm 74 and the second arm 76 each includes a curved surface 82 having a curvature that matches the curvature of the return manifold 50. A space 84 is defined by the curved wall 72 and the curved surfaces 82 of the first arm 74 and the second arm 76 and defines a circular opening having a shape that corresponds to the shape of the return manifold 50. An opening 86 having a width W is defined between the first arm 74 and the second arm 76. Before attachment of the adapter 68 to the return manifold 50, the width W of the opening 86 is less than the diameter Y of the return manifold 50. As the first arm 74 and the second arm 76 are flexible, the width W of the opening 86 can increase.

In one example, the curved wall 72 includes segments 88 spaced apart by openings 89. The openings 89 are spaced equally along the length X of the adapter 68. The curved wall 72 can also include an opening 90 within each segment 88. The openings 89 and 90 are formed during the injection molding process and can have any shape. The adapter 68 also includes a first wall 92 and a second wall 94 that extend from the second side 80 of the curved wall 72 (shown in Figure 7). The walls 92 and 94 provide structural support and rigidity to the adapter 68. The first wall 92 includes a first portion 96 and a second portion 98. The first portion 96 connects the second portion 98 to the curved wall 72.

The second portion 98 of the first wall 92 and the second wall 94 are substantially parallel and extend in a direction opposite to the first arm 74 and the second arm 76. The first portion 96 includes a plurality of apertures 100 spaced along the length X of the adapter 68. When the microchannel heat exchanger 46 is assembled, the plurality of apertures 100 receive wires of a wire grill (not shown) that surrounds the microchannel heat exchanger 46 to provide protection from debris and objects, such as leaves.

As shown in Figures 12 and 13, the second wall 94 of the adapter 68 includes a plurality of apertures 104 that can each receive a fastener 122, such as a screw, that secures the adapter 68, and therefore the microchannel heat exchanger 46, to a surrounding cabinet 124 .

In one example, one or both of the first wall 92 and the second wall 94 includes a sheet metal strip (not shown) to provide additional structure and support to the adapter

68. The sheet metal strip can be attached to a surface of the first wall 92 or the second wall 94 or can be impregnated in the first wall 92 or the second wall 94 during the injection molding process.

A plurality of u-shaped members 106 (a plurality of engagement features) extend from the second side 80 of the curved wall 72 and are located between the first wall 92 and the second wall 94. The u-shaped members 106 are equally spaced along the length

X of the adapter 68. The u-shaped members 106 have a size and shape similar to the u- shaped tubes 44 of the prior art heat exchanger 36 and simulate the u-shaped tubes 44.

The adapter 68 is attached to the return manifold 50 of the microchannel heat exchanger 46. The adapter 68 is attached by the plurality of fasteners 70 to a body 51 of the return manifold 50. That is, the adapter 68 is attached between the ends 53 and 55 of the return manifold 50. When the adapter 68 is attached to the return manifold 50, the adapter 68 is substantially parallel to the return header 50 and substantially perpendicular to the plurality of microchannel tubes 52. As shown in Figure 8, prior to attachment, the adapter 68 is positioned such that the first side 78 of the curved wall 72 faces the return manifold 50. The diameter Y of the return manifold 50 is greater than the width W of the opening 86 defined between the first arm 74 and the second arm 76. The return manifold 50 is positioned between the first arm 74 and the second arm 76, biasing the flexible arms 74 and 76 apart and increasing the width W of the opening 86 to allow the return manifold 50 to pass between the arms 74 and 76 and to be received inside the space 84. The first arm 74 and the second arm 76 return to the original position, retaining the adapter 68 on the return manifold 50.

Figures 9 and 10 illustrate a perspective view of the adapter 68 attached to the return manifold 50 of the microchannel heat exchanger 46. The u- shaped members 106 extend from the second side 80 of the curved wall 72 and simulate the u-shaped tubes 44 of the prior art heat exchanger 36.

As shown in Figure 11, a second adapter 108 can be attached to the inlet/outlet manifold 48. The second adapter 108 attaches to the inlet/outlet manifold 48 in the same manner as the adapter 68 attaches to the return manifold 50. The second adapter 108 includes fasteners (not shown) that correspond to the fasteners 70 of the adapter 68, and the second adapter 108 includes a first wall 110 and a second wall 112 that correspond to the first wall 92 and the second wall 94, respectively, of the adapter 68. The second wall 112 includes apertures 132 that receive a fastener (not shown) to secure the microchannel heat exchanger 46 to the cabinet (not shown), and the first wall 110 includes apertures (not shown) that receive wires of the wire grill that provides protection. The second adapter 108 also includes an inlet port 114 in fluid communication with the inlet tube 54, and an outlet port 116 in fluid communication with the outlet tube 60.

During forming or bending of the microchannel heat exchanger 46, the forming arm 66 of the forming machine 64 engages and interacts with the u-shaped members 106 of the adapter 68 in the same manner that the forming arm 66 engages the u-shaped tubes 44 of the prior art heat exchanger 36. The forming machine 64 then forms or bends the microchannel tubes 52 in three locations 126a, 126b and 126c such that the length of the microchannel tubes 52 define a substantially square shape that surrounds a space 122. The resulting bent microchannel tubes 52 defines a first side 118a, a second side 118b, a third side 118c and a fourth side 118d. When the adapter 68 is attached to the return manifold 50, the microchannel heat exchanger 46 can be formed or bent by the same forming machine 64 that forms or bends the prior art heat exchangers 36, allowing the prior art heat exchanger 36 and the microchannel heat exchanger 46 to be formed on the same assembly line or concurrently on the same assembly line, increasing efficiency of the production and preventing the need for a separate forming machine for the microchannel heat exchanger 46. Once the microchannel tubes 52 are formed or bent, the forming machine 64 disengages from the u- shaped members 106 of the microchannel heat exchanger 46.

The adapter 68 also assists in attachment of the microchannel heat exchanger 46 to the cabinet that contains or covers the microchannel heat exchanger 46. When adapter 68 is attached to the microchannel heat exchanger 46, the adapter 68 slightly raises the microchannel heat exchanger 46. In one example, the microchannel heat exchanger 146 is raised half an inch by the adapter 68. The fan 30 or 32 (shown in Figure 2) can be installed in the space 122 defined by the four walls 102a, 102b, 102c and 102d to draw air over the microchannel tubes 52 during heat exchange. A base pan 120 (see Figure 10) is received under the microchannel tubes 52 of the microchannel heat exchanger 46. The cabinet is positioned over the microchannel heat exchanger 46, and the fasteners (not shown) are received in the apertures 104 and 132 of the walls 94 and 112, respectively, to attach the adapters 68 and 108, respectively, to the cabinet. The foregoing description is only exemplary of the principles of the invention.

Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.

Claims

CLAIMSWhat is claimed is:

1. A heat exchanger comprising: a first manifold; a second manifold; a plurality of tubes extending between the first manifold and the second manifold; and an adapter mounted to the first manifold, wherein the adapter includes a plurality of engagement features engageable by a forming machine to form the heat exchanger into a shape.

2. The heat exchanger as recited in claim 1 wherein the adapter is plastic.

3. The heat exchanger as recited in claim 1 wherein the first manifold and the second manifold are substantially cylindrical.

4. The heat exchanger as recited in claim 1 wherein the adapter is substantially parallel to the first manifold and substantially perpendicular to the plurality of tubes.

5. The heat exchanger as recited in claim 1 wherein the adapter includes a curved wall having a first side and an opposing second side.

6. The heat exchanger as recited in claim 5 including a plurality of attachment members that attach the adapter to the first manifold, wherein each of the plurality of attachment members include a first arm and a second arm, and the first arm and the second arm are flexible.

7. The heat exchanger as recited in claim 6 wherein the adapter includes a curved wall having a first side and an opposing second side.

8. The heat exchanger as recited in claim 7 wherein the first arm and the second arm extend from the first side of the curved wall and each include a curved portion, and the curved wall and the curved portions of the first arm and the second arm define a space that receives the first manifold.

9. The heat exchanger as recited in claim 5 wherein the adapter includes a first wall and a second wall that extend from the opposing second side of the curved wall.

10. The heat exchanger as recited in claim 9 wherein the first wall of the adapter includes a plurality of apertures.

11. The heat exchanger as recited in claim 9 wherein the second wall includes a plurality of apertures.

12. The heat exchanger as recited in claim 9 wherein the plurality of engagement features comprise a plurality of u-shaped members that extend from the opposing second side of the curved wall and are located between the first wall and the second wall.

13. The heat exchanger as recited in claim 1 wherein the first manifold is a return manifold and the second manifold is an inlet/outlet manifold.

14. The heat exchanger as recited in claim 1 wherein a second adapter is mounted to the second manifold, and the second adapter includes a plurality of attachment members that attach the second adapter to the second manifold and two walls that each include a plurality of apertures.

15. The heat exchanger as recited in claim 14 wherein the first manifold includes a first end, a second end, and a body defined between the first end and the second end, and the plurality of attachment members attach the adapter to the body of the first manifold.

16. The heat exchanger as recited in claim 1 wherein the heat exchanger is a microchannel heat exchanger.

17. The heat exchanger as recited in claim 1 wherein the adapter is a single, unitary component.

18. The heat exchanger as recited in claim 1 wherein the adapter communicates with a cabinet for mounting the heat exchanger to the cabinet.

19. An adapter attachable to a manifold of a heat exchanger, the adapter comprising: a curved wall including a first side and an opposing second side; a plurality of attachment members located on the first side of the curved wall, wherein the plurality of attachment members and the curved wall define a space to receive a manifold of a heat exchanger; and a plurality of u-shaped members located on the opposing second side of the curved wall.

20. The adapter as recited in claim 19 wherein the adapter is plastic.

21. The adapter as recited in claim 19 wherein the plurality of attachment members include a flexible first arm and a flexible second arm each having a curved portion, wherein the curved wall and the curved portions of the first arm and the second arm define the space.

22. The adapter as recited in claim 19 including a first wall and a second wall that extend from the opposing second side of the curved wall.

23. The adapter as recited in claim 22 wherein the first wall and the second wall include a plurality of apertures.

24. The adapter as recited in claim 19 wherein the plurality of u- shaped members extend from the opposing second side of the curved wall.

25. The adapter as recited in claim 19 wherein the adapter is a single, unitary component.