WO2009110663A1

WO2009110663A1 - Heat exchanger and method of manufacturing the same

Info

Publication number: WO2009110663A1
Application number: PCT/KR2008/004049
Authority: WO
Inventors: Seung-Cheol Baek; Young-Hwan Ko; Tae-Gyun Park; Sim-Won Chin
Original assignee: Lg Electronics Inc.
Priority date: 2008-03-07
Filing date: 2008-07-09
Publication date: 2009-09-11
Also published as: CN101889187A

Abstract

A heat exchanger and a method of manufacturing the same are provided. The heat exchanger includes one or more fins and one or more tubes penetrating the fin. The fin is provided with a plurality of refrigerant passages.

Description

HEAT EXCHANGER AND METHOD OF MANUFACTURING

THE SAME

Technical Field

[1] The present disclosure relates to a heat exchanger and method of manufacturing the same. Background Art

[2] Generally, a refrigerant system includes a compressor, a condenser, an expanding device, and an evaporator. The condenser and evaporator function to allow a refrigerant therein heat-exchanges with external fluid and thus it may be referred to as "heat exchanger."

[3] The heat exchangers may be classified into fin-tube type heat exchangers and micro- channel tube type heat exchangers. The fin-tube type heat exchanger includes a plurality of fins and a plurality of tubes each having a circular or nearly circular section and penetrating the fins. The micro-channel tube type heat exchanger includes a plurality of flat tubes and a pin provided between the flat tubes and having a plurality of bending portions. Disclosure of Invention Technical Problem

[4] Embodiments provide a heat exchanger that is improved in heat exchange efficiency and a method of manufacturing the heat exchanger. Technical Solution

[5] In one embodiment, a heat exchanger includes one or more fins; and one or more tubes penetrating the fin and provided with a plurality of refrigerant passages.

[6] In another embodiment, a method of manufacturing a heat exchanger includes stacking a plurality of fins; and making a plurality of refrigerant fins each provided with a plurality of refrigerant passages penetrate the fins.

Advantageous Effects

[7] According to the embodiments, since the heat exchange is performed by the refrigerant tube provided with the refrigerant passages and the fins penetrating the refrigerant tubes, the heat exchange performance can be improved.

[8] The refrigerant tubes are installed by entirely penetrating the fins, the condensed water can effective flow down along the fins when the heat exchanger is used as an evaporator.

[9] In addition, since the fin, refrigerant tube, connector, return tube, and header are fixed at a time through a brazing process, the manufacturing process can be simplified.

[10] Further, the return tube is formed to have a curvature radius greater than 1/2 of a distance between the refrigerant tubes, the number of the refrigerant tubes that can be installed in the heat exchanger of an identical size can be maximized and thus the heat exchange efficiency of the heat exchanger can be further improved.

[11] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. Brief Description of the Drawings

[12] Fig. 1 is a front view of a heat exchanger according to an embodiment.

[13] Fig. 2 is a cross-sectional view of a contacting portion between a fin and a refrigerant tube.

[14] Fig. 3 is a perspective view of a connector according to an embodiment.

[15] Fig. 4 is a cross-sectional view illustrating a coupling state of a refrigerant tube with a connector.

[16] Fig. 5 is a perspective view of a return tube according to an embodiment.

[17] Fig. 6 is a cross-sectional view illustrating a coupling state of a return tube with a refrigerant tube according to an embodiment.

[18] Fig. 7 is a flowchart illustrating a process for manufacturing a heat exchanger according to an embodiment. Best Mode for Carrying Out the Invention

[19] Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings.

[20] Fig. 1 is a front view of a heat exchanger according to an embodiment.

[21] Referring to Fig. 1, a heat exchanger 100 of an embodiment includes a plurality of flat fins 110, a plurality of refrigerant tubes 120 installed penetrating the plurality of fins 110, a plurality of connectors 140 connecting some of the refrigerant tubes 120 to a capillaries 160, a plurality of return tubes 140 each connecting adjacent two refrigerant twos 120, and a header 150 connected to the plurality of the refrigerant tubes 120.

[22] In more detail, the fins 110 are formed in a rectangular flat plate shape having a predetermined length. The plurality of the fins 110 substantially function to enlarge a heat exchange area between a refrigerant flowing along the refrigerant tubes 120 and external fluid. The fins 110 are spaced apart from each other at predetermined intervals.

[23] For example, the refrigerant tubes 120 are formed to have a predetermined length through a compression molding process. The refrigerant tubes 120 are formed in a flat shape. That is, each of the refrigerant tubes 120 is formed to have a thin rectangular section. [24] The plurality of the refrigerant tubes 120 are spaced apart from each other in a vertical direction and penetrate the fins 110. [25] The refrigerant tubes 120 and the fins 110 are formed of, for example, an aluminum material that is excellent in thermal conductivity. [26] Hereinafter, the uppermost tube in Fig. 1 will be referred to "first refrigerant tube

121." The tubes located under the first refrigerant tube 121 will be referred to as

"second to sixth refrigerant tubes 122, 123, 124, 125, and 126." [27] Meanwhile, the header 150 is connected to the first and fourth refrigerant tubes 121 and 124. When the heat exchanger functions as a condenser, the header 150 operates to dispense the refrigerant to the first and fourth refrigerant tubes 121 and 124. [28] Fig. 2 is a cross-sectional view of a contacting portion between a fin and a refrigerant tube.

[29] Referring to Fig. 2, a plurality of refrigerant passages 120P along which the refrigerant flows are formed in the refrigerant tube 120. A plurality of partitions 127 for dividing the inside of the refrigerant tube 120 into the plurality of the passages 120P are provided in the refrigerant passage 120P.

[30] Each of the partitions 127 has a same length as the refrigerant tube. Therefore, the refrigerant passages 120P in the refrigerant tube 120 extend through an entire length of the refrigerant tube 120. [31] A brazing layer 180 is formed on a contacting portion between the refrigerant tubes

120 and the fins 110. The brazing layer 180 is formed as a brazing material adhered to the refrigerant tubes 120 is melted. This will be described in more detail later. [32] Fig. 3 is a perspective view of a connector according to an embodiment and Fig. 4 is a cross-sectional view illustrating a coupling state of a refrigerant tube with a connector. [33] Referring to Figs. 3 and 4, the connectors 130 connect some of the refrigerant tubes

120 each having the rectangular section to the circular capillaries 160. That is, the connector 130 is designed to interconnect the refrigerant tube 120 and capillary 160 having different shapes. [34] In the embodiment, the connectors 130 connect the third and sixth refrigerant tubes

123 and 126 to the respective capillaries 160. [35] In more detail, each of the connectors 130 includes a first connector 130a to which the refrigerant tube 120 is connected and a second connector 130b to which the capillary 160 is connected. [36] The first connector 130a is provided with an opening 132 in which the refrigerant tube 120 is inserted. The opening 132 is shaped to correspond to the refrigerant tube 120. A coupling hole 131 to which the capillary 160 is coupled is formed through a side of the second connector 130b.

[37] In a state where the capillary 160 is coupled to the coupling hole 131, the first connector 130a is inserted into the refrigerant tube 120, thereby communicating the capillary 160 with the refrigerant tube 120.

[38] The first connector 130a has a greater sectional area than the second connector 130b.

Therefore, a stepped portion 133 is formed at the connecting portion between the first and second connectors 130a and the 130b. When the refrigerant tube 120 is inserted into the connector 130, an end portion of the refrigerant tube 120 closely contacts the stepped portion 133.

[39] The stepped portion 133 is formed away from the coupling hole 131. When the heat exchanger functions as an evaporator, the refrigerant discharged from the capillary 160 is supplied to the refrigerant tube 120 via an inner space of the second connector 130b and thus the refrigerant can be effectively supplied to the refrigerant passages 120P of the refrigerant tube 120. In addition, the inner surface of the refrigerant tube 120 and the inner surface of the second connector 130b are on a same horizontal surface. Therefore, a flow resistance of the refrigerant in the refrigerant tube 120 and the second connector 130b can be minimized.

[40] A brazing layer 180 may be formed on a contacting portion between the first connector 130a and the refrigerant tube 120.

[41] Fig. 5 is a perspective view of a return tube according to an embodiment and Fig. 6 is a cross-sectional view illustrating a coupling state of a return tube with a refrigerant tube according to an embodiment.

[42] Referring to Figs. 5 and 6, the return tube 140 is designed to interconnect end portions of the adjacent tubes 120 so that the adjacent tubes 120 communicate with each other.

[43] In the embodiment, the return tubes 140 interconnect the first and second refrigerant tubes 122, the second and third refrigerant tubes 122 and 123, the fourth and fifth refrigerant tubes 124 and 125, and the fifth and sixth refrigerant tubes 125 and 126, respectively.

[44] Each of the return tubes 140 is formed to have a same section as the refrigerant tube

120 through the compression molding process. Each of the return tubes 140 is bent to have an open curve. The return tube 140 is generally formed in a horseshoe shape having one curved portion 141 and two straight portions 143.

[45] The curved portion 141 has a curvature radius R greater than 1/2 of a length L between the adjacent refrigerant tubes 120.

[46] This structure can make it easy to form the return tube 140 while minimizing the distance between the adjacent refrigerant tubes 120. [47] As the distance L between the adjacent refrigerant tubes 120 is reduced, the number of the refrigerant tubes 120 provided in the heat exchanger of an identical size increases. When the number of the refrigerant tubes 120 increases, a heat exchange capacity of the heat exchanger increases.

[48] However, as the distance L between the adjacent refrigerant tubes 120 is reduced, the curvature radius of the return tube 140 is reduced. This makes it difficult to bend the return tube 140.

[49] Therefore, the curvature radius R of the curved portion 140 is set to be greater than

1/2 of the distance L between the adjacent refrigerant tubes 120. In this case, even when the length L between the adjacent refrigerant tubes 120 is reduced, the forming of the return tube 140, i.e., the bending of the return tube 140, can be easily realized.

[50] The two straight portions 143 are provided on opposite end portions of the curved portion 141. End portions of the respective adjacent refrigerant tubes 120 are respectively inserted into the straight portions 143. Therefore, the respective straight portions 143 are designed to have a larger section than the refrigerant tubes 120.

[51] A plurality of refrigerant passages 140P are provided in the curved portion 141. The number of the refrigerant passages 140P is same as the number of the refrigerant passages 120P of the refrigerant tube 120. Therefore, the refrigerant passages 140P communicate with the respective refrigerant passages 120P of the refrigerant tube 120. A plurality of partitions for dividing the inside of the curved portion 141 into the plurality of the refrigerant passages 140P are provided in the curved portion 140P.

[52] A brazing layer 180 may be formed at the contacting portion between the return tube

140 and the refrigerant tube 120.

[53] Meanwhile, the fins 110 and the refrigerant tubes 120 are coupled to each other by a brazing process. The refrigerant tubes and the connectors 130 are also coupled to each other by the brazing process. The refrigerant tubes 120 and the return tubes 140 are also coupled to each other by the brazing process.

[54] That is, the fins 110 and the refrigerant tubes 120 are coupled to each other as the brazing material between them are melted. The refrigerant tubes and the connectors 130 are also coupled to each other as the brazing material between them are melted. The refrigerant tubes 120 and the return tubes 140 are also coupled to each other as the brazing material between them are melted.

[55] The following will describe a method of manufacturing the heat exchanger according to an embodiment.

[56] Fig. 7 is a flowchart illustrating a process for manufacturing the heat exchanger according to an embodiment.

[57] Referring to Fig. 7, the plurality of the refrigerant tubes 120 and the plurality of the fins 110 are first prepared. The brazing material is provided in the form of a sheet. The brazing material may be clad.

[58] The brazing material is coupled or adhered to the circumferences of the refrigerant tubes 120. The plurality of the refrigerant tubes 120 to which the brazing material is applied are installed penetrating the plurality of the fins 110 (Sl 1).

[59] In addition, the brazing materials are adhered to the circumference of the refrigerant tubes 123 and 126 that will be coupled to the connectors 130 (S 13). The brazing materials are adhered to the circumferences of the refrigerant tubs 121 to 126 that will be coupled to the return tubes 140 and the refrigerant tubes 120 are coupled to the return tubes 140 (S 13).

[60] The brazing materials are adhered to the circumferences of some of the refrigerant tubes 120, these refrigerant tubes 120 are coupled to the header 150.

[61] Next, the fins 110, refrigerant tubes 120, connectors 130, return tubes 140, and header 150 that are assembled in the above processes are heated (Brazing process) (S15).

[62] For example, when the fins 110, refrigerant tubes 120, connectors 130, return tubes

140, and header 150 are heated at a temperature of 580-610⁰C, the brazing materials are melted to form the brazing layers. As a result, when the fins 110, refrigerant tubes 120, connectors 130, return tubes 140, and header 150 are fixed to complete the heat exchanger. At this point, the melting point of the brazing material is less than the melting point of the fins 110, refrigerant tubes 120, connectors 130, return tubes 140, and header 150.

[63] As described above, in a state where the heat exchanger is formed through the brazing process, oils in refrigerant tubes 120, connectors 130, and return tubes 140 are dried (S 17). When the oil drying process is completed in the process S 17, the corrosion resistance layers are coated on the fins 110, refrigerant tubes 120, connectors 130, and return tubes 140 (S 19). In addition, when the coating of the corrosion resistance layers is completed, hydrophilic layers are formed on outer circumferences of the fins 110, refrigerant tubes 120, connectors 130, and return tubes 140 (actually, on outer circumferences of the corrosion resistance layers) (S21).

[64] When the coating of the corrosion resistance layers and the hydrophilic layers is completed, a leakage test is performed for the heat exchanger (S23). The leakage test is performed by along fluid to flow along the heat exchanger using a predetermined pressure 20kg/cm2 and detecting if there is any leak in the heat exchanger.

[65] The following will describe a refrigerant flowing process of the heat exchanger.

[66] First, when the heat exchanger is used as the condenser, a gas-phase refrigerant is directed from the compressor to the header 150 through the refrigerant tubes 170.

[67] The refrigerant directed to the header 150 is dispensed to the first and fourth refrigerant tubes 121 and 124. The refrigerant of the first refrigerant tube 121 is directed to the capillary 160 connected to the third refrigerant tube 123 through the second and third refrigerant tubes 122 and 123. The refrigerant of the fourth refrigerant tube 124 is directed to the capillary 160 connected to the sixth refrigerant tube 126 through the fifth and sixth refrigerant tubes 125 and 126.

[68] When the heat exchanger is used as the evaporator, the refrigerant expands as it is directed to a condenser (not shown) to the capillary 160. The expanded refrigerant is directed to the third and sixth refrigerant tubes 123 and 126.

[69] The refrigerant directed to the third refrigerant tube 123 is directed to the second and first refrigerant tubes 122 and the 121, after which it is directed to the header 150. The refrigerant of the sixth refrigerant tube 126 is directed to the header 150 through the fifth and fourth refrigerant tubes 125 and 124. The refrigerant directed to the header 150 is directed to a compressor (not shown) through the refrigerant tube 170.

[70] According to the embodiment, since the refrigerant flows along the tubes each having the plurality of the passages, the heat exchanging area between the refrigerant and the external fluid increases and thus the heat exchange efficiency is improved.

[71] In addition, when the heat exchanger functions as the evaporator, since the condensed water generated in the course of heat-exchanging of the refrigerant in the heat exchanger with the external fluid effectively flows down along the fins, the phenomenon where the condensed water is collected in the heat exchanger is prevented and thus the heat exchange performance of the heat exchanger is improved.

[72] Although six tubes are provided in the embodiment, the present invention is not limited to this configuration. That is, the number of the tubes may be less or greater than six.

[73] Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.

[74]

Claims

[ 1 ] A heat exchanger comprising : one or more fins; and one or more tubes penetrating the fin and provided with a plurality of refrigerant passages.

[2] The heat exchanger according to claim 1, wherein the refrigerant tube is formed to be flat.

[3] The heat exchanger according to claim 1, wherein an entire outer circumference of the refrigerant tube penetrates the fin.

[4] The heat exchanger according to claim 1, wherein the fin and the refrigerant tube are coupled to each other by a brazing process.

[5] The heat exchanger according to claim 4, further comprising a brazing layer that is formed at a contacting portion between the fin and the refrigerant tube by a brazing material melted.

[6] The heat exchanger according to claim 4, wherein the fin and tube are formed of aluminum and the brazing material is clad.

[7] The heat exchanger according to claim 1, further comprising a return tube interconnecting adjacent two refrigerant tubes. [8] The heat exchanger according to claim 7, wherein a plurality of refrigerant passages are formed in at least a portion of an inside of the return tube. [9] The heat exchanger according to claim 7, wherein the return tube comprises two straight portions to which the respective refrigerant tubes are coupled and a curved portion interconnecting the two straight portions; and the curved portion has a same section as the refrigerant tube. [10] The heat exchanger according to claim 1, further comprising: a plurality of capillaries communicating with some of the refrigerant tubes; and a plurality of connectors connecting the respective capillaries to the some of the refrigerant tubes. [11] The heat exchanger according to claim 10, wherein connector comprises: a first connector in which the refrigerant tube is inserted; and a second connector which extends from the first connector and having a couling hole to which the capillary is coupled. [12] A method of manufacturing a heat exchanger, comprising: stacking a plurality of fins; and making a plurality of refrigerant fins each provided with a plurality of refrigerant passages penetrate the fins. [13] The method according to claim 12, wherein a brazing material is adhered to an outer surface of each of the refrigerant tubes penetrating the fins. [14] The method according to claim 13, further comprising melting the brazing materials adhered to the fins and tubes. [15] The method according to claim 12, wherein an entire outer circumference of the refrigerant tube penetrates the fin. [16] The method according to claim 12, further comprising coupling return tubes to the two adjacent refrigerant tubes. [17] The method according to claim 16, wherein brazing materials are adhered to outer surfaces of the two adjacent refrigerant tubes. [18] The method according to claim 17, further comprising connecting a header to some of the refrigerant tubes. [19] The method according to claim 18, wherein brazing materials are adhered to outer surfaces of the some refrigerant tubes that coulped to the header. [20] The method according to claim 19, further comprising heating the brazing materials to melt the brazing materials.