Heat exchanger and method for manufacturing same

The heat exchanger includes at least one tube array in which refrigerant flows, the tube array includes a plurality of tubes each having a channel formed therein, and connection members coupled to opposite ends of the tubes so as to interconnect the tubes, and the tubes are injection molded integrally with the connection members.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage Application, which claims the benefit under 35 U.S.C. § 371 of PCT International Patent Application No. PCT/KR2015/002568, filed Mar. 17, 2015, which claims the foreign priority benefit under 35 U.S.C. § 119 of Korean Patent Application No. 10-2014-0032198, filed Mar. 19, 2014, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

Embodiments of the present invention relate to a heat exchanger having an improved structure capable of enhancing heat exchange efficiency, and a method of manufacturing the same.

BACKGROUND ART

In general, a heat exchanger is an apparatus which includes a tube in which refrigerant flows and exchanges heat with ambient air, a heat exchange fin coming into contact with the tube so as to enlarge a heat radiation area, and headers communicating with opposite ends of the tube and, as such, refrigerant exchanges heat with ambient air. The heat exchanger includes an evaporator or a condenser, and may form a refrigeration cycle system together with a compressor to compress refrigerant and an expansion valve to expand refrigerant.

In general, the tube of the heat exchanger has a tubular shape made of a copper material and the heat exchange fin has a thin plate shape made of an aluminum material.

The tube and heat exchange fin of the heat exchanger made of a metal material exhibit difficulty in shape deformation, thereby causing an increase in manufacturing costs during shape deformation thereof.

In addition, since the tube is generally manufactured by welding, refrigerant leakage may frequently occur through a gap generated during welding.

Accordingly, for manufacture of a heat exchanger which includes a metal tube and a metal heat exchange fin, complicated manufacturing processes such as a welding process and a refrigerant leakage inspection process are received. For this reason, manufacturing costs of the heat exchanger are increased and a long time is taken to manufacture the heat exchanger.

DISCLOSURE

Technical Problem

It is an aspect of the present invention to provide a heat exchanger having an improved structure capable of enlarging a heat exchange area between refrigerant and ambient air, and a method of manufacturing the same.

It is another aspect of the present invention to provide a heat exchanger having an improved structure capable of simultaneously satisfying mass production and cost reduction, and a method of manufacturing the same.

It is a further aspect of the present invention to provide a heat exchanger having an improved structure capable of preventing refrigerant leakage, and a method of manufacturing the same.

Technical Solution

In accordance with one aspect of the present invention, a heat exchanger includes at least one tube array in which refrigerant flows, the tube array includes a plurality of tubes each having a channel formed therein and connection members coupled to opposite ends of the tubes so as to interconnect the tubes, and the tubes are injection molded integrally with the connection members.

The tubes and the connection members may be made of a polymeric material.

The heat exchanger may further include headers coupled to opposite ends of the tube array.

The headers may include main headers respectively coupled to the opposite ends of the tube array, and the main headers may be injection molded so as to be coupled to the opposite ends of the tube array.

The tube array may include a plurality of tube arrays arranged in parallel, and the main headers may be injection molded so as to be coupled to opposite ends of the tube arrays to form a tube assembly configured by interconnecting the tube arrays.

The main headers may be made of a polymeric material.

The main headers may be injection molded so as to be coupled to the connection members, and each of the connection members may be formed, at an outer surface thereof, with at least one refrigerant leakage prevention groove recessed inward of the connection member.

Each of the headers may further include a sub-header coupled to an outer side of the corresponding main header so as to form a refrigerant flow passage, and a coupling method of the sub-header and the main header may include a thermal bonding method or an induction heating method.

A plurality of cooling fins may be provided at an outer peripheral surface of each tube, and the cooling fins may be injection molded integrally with the tube and the connection members.

The cooling fins may be made of a polymeric material.

A plurality of cooling fins may be provided at an outer peripheral surface of each tube, and the cooling fins may each have an annular shape and be arranged along the outer peripheral surface of the tube in a longitudinal direction of the tube.

The cooling fins may each have an inclined annular shape.

The cooling fins may include first cooling fins each having an annular shape inclined toward one end of each tube and second cooling fins each having an annular shape inclined toward the other end of the tube, and the first and second cooling fins may form at least one intersection point.

The tubes may include a first tube provided, on an outer peripheral surface thereof, with the first cooling fins and a second tube adjacent to the first tube, the second cooling fins being provided at an outer peripheral surface of the second tube, and facing ends of the first and second cooling fins may be alternately arranged in the longitudinal direction of the tubes.

The sub-header may be made of a polymeric material, and the sub-header may include an inflow header having an inlet through which the refrigerant is introduced toward the tubes and an outflow header having an outlet through which the refrigerant is discharged.

The heat exchanger may further include a pipe connected to at least one of the inlet and the outlet such that the refrigerant flows through the pipe, the pipe being made of a material different from the sub-header, and the pipe may be inserted into the sub-header during injection molding thereof so as to be formed integrally with the sub-header.

The pipe may be made of a copper (Cu) material, and a leakage prevention ring may be disposed between the pipe and the sub-header in order to prevent the refrigerant from leaking between the pipe and the sub-header.

The leakage prevention ring may be made of a silicone or rubber material.

In accordance with another aspect of the present invention, a heat exchanger includes a plurality of tubes arranged in parallel such that refrigerant flows through the tubes, headers coupled to opposite ends of the tubes so as to interconnect the tubes, each of the headers having an inlet and an outlet for the refrigerant, and a pipe coupled to at least one of the inlet and the outlet such that the refrigerant flows along the tubes, wherein the pipe is inserted into the header during injection molding thereof so as to be formed integrally with the header.

At least one leakage prevention ring may be disposed between the pipe and the header in order to prevent the refrigerant from leaking between the pipe and the header.

The pipe may include a body therein having a passage in which the refrigerant flows and a neck connected to one end of the body so as to be coupled to at least one of the inlet and the outlet, the neck having a diameter different from the body, and the leakage prevention ring may be disposed on an outer peripheral surface of the body so as to be close to the neck.

The neck may have a larger diameter than the body, and the diameter of the neck may be reduced with decreasing distance to the body.

The header may include a protrusion portion protruding outward of the header so as to provide the inlet and the outlet, and the body may be coupled to at least one of the inlet and the outlet such that the leakage prevention ring is located inside the protrusion portion.

In accordance with another aspect of the present invention, a heat exchanger includes a plurality of tubes each having a channel formed therein, the tubes being arranged in parallel, a plurality of cooling fins coupled to a surface of each tube, the cooling fins being spaced apart from each other in a longitudinal direction of the tube, and headers coupled to opposite ends of the tubes, wherein the tubes are injection molded integrally with the cooling fins.

In accordance with a further aspect of the present invention, a method of manufacturing a heat exchanger includes integrally injection molding a plurality of tubes and connection members coupled to opposite ends of the tubes so as to form at least one tube array, injection molding main headers to opposite ends of the tube array, and coupling a sub-header to an outer side of each of the main headers so as to form a refrigerant flow passage by coupling of the main header and the sub-header.

The tube array may include a plurality of tube arrays, the tube arrays may be arranged in parallel, and the main headers may be injection molded by coupling the main headers to the opposite ends of the tube arrays.

A plurality of cooling fins may be provided at an outer peripheral surface of each tube, and the cooling fins may be injection molded integrally with the tube and the connection members.

A coupling method of the sub-header and the corresponding main header may include a thermal bonding method or an induction heating method.

Each of the connection members may be formed, at an outer surface thereof, with at least one refrigerant leakage prevention groove recessed inward of the connection member.

The sub-header may be injection molded by inserting a pipe, through which refrigerant flows, into the sub-header.

The sub-header may be injection molded by inserting the pipe into the sub-header such that a portion of the pipe is located outside the sub-header.

The sub-header may be injection molded by inserting the pipe into the sub-header in a state in which a leakage prevention ring is disposed on an outer peripheral surface of the pipe in order to prevent the refrigerant from leaking between the pipe and the sub-header.

A first mold may be coupled to a second mold, a third mold may be coupled to a fourth mold so as to form a molding space together with the first and second molds, a piston core may be inserted into the molding space such that each of the tubes has a channel therein through which refrigerant flows, resin may be injected into the molding space so as to injection mold the tube array, and the piston core may be separated from the molding space after separation of the first, second, third, and fourth molds from one another.

The first mold may be coupled to the second mold so as to form shapes of the tubes and the cooling fins.

The third and fourth molds may be coupled to the first and second molds so as to form shapes of the connection members.

Advantageous Effects

As is apparent from the above description, it may be possible to enhance heat exchange efficiency by integrally forming a tube and a cooling fin with a polymeric material and thus by enlarging a contact area between refrigerant flowing in the tube and ambient air.

It may be possible to reduce process costs since the tube made of a polymeric material may be produced in quantity by injection and extrusion molding. In addition, a lightweight heat exchanger may be obtained due to characteristics of the polymeric material.

Since shape deformation of the polymeric tube is easy, the polymeric tube may properly correspond to deformation of products using the heat exchanger.

It may be possible to improve coupling reliability between a main header and a connection member by forming at least one refrigerant leakage prevention groove on an outer surface of the connection member and thus to prevent refrigerant leakage between the main header and the connection member.

MODE FOR INVENTION

Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In addition, terms such as, “front end”, “rear end”, “upper portion”, “lower portion”, “upper end”, and “lower end” are defined with respect to the drawings, and the shape and the position of the components are not limited to the terms. Hereinafter, reference numeral S may represent a sample.

FIG. 1is a perspective view illustrating an external appearance of a heat exchanger according to an embodiment of the present invention.FIG. 2is an exploded perspective view illustrating the heat exchanger according to the embodiment of the present invention.FIG. 3is a perspective view illustrating tube arrays and one tube assembly of the heat exchanger according to the embodiment of the present invention.

As shown inFIGS. 1 to 3, a heat exchanger, which is designated by reference numeral1, may include a tube array100and a tube assembly200as configuration units thereof.

The heat exchanger1may include at least one tube array100within which refrigerant flows.

The tube array100may be formed by coupling a plurality of tubes10, and the tube assembly200may be formed by coupling a plurality of tube arrays100. The heat exchanger1may be formed by coupling at least one tube assembly200.

The heat exchanger1may include a plurality of tubes10, a plurality of cooling fins20, and headers30aand30b.

The tubes10may be arranged in parallel.

Each of the tubes10may have a channel11formed therein such that refrigerant as a fluid may flow along the channel11.

The refrigerant exchanges heat with ambient air while undergoing phase change (compression) from gas phase to liquid phase, or exchanges heat with ambient air while undergoing phase change (expansion) from liquid phase to gas phase. The heat exchanger1is used as a condenser when the refrigerant undergoes phase change from gas phase to liquid phase, whereas the heat exchanger1is used as an evaporator when the refrigerant undergoes phase change from liquid phase to gas phase.

The tubes10may be made of a polymeric material.

The tubes10may be formed by extrusion and injection molding. Hereinafter, the tubes10are regarded as being formed by injection molding for convenience of description.

Opposite ends of the tubes10in each tube array100may be coupled to connection members12, respectively.

The connection members12may be coupled to opposite ends of the tubes10, respectively, so as to form one tube array100.

The connection members12may be made of a polymeric material, similarly to the tubes10.

In addition, the connection members12may be injection molded integrally with the tubes10.

The headers30aand30bmay include a first header30aand a second header30bwhich are respectively coupled to outer sides of the connection members12. The first and second headers30aand30bmay be coupled to the outer sides of the connection members12such that the first header30ais directed in a first direction A and the second header30bis directed in a second direction B. The first and second headers30aand30bare spaced apart from each other by a predetermined distance, and the tubes10may be disposed between the first and second headers30aand30b.

The first header30amay communicate with ends of the tubes10directed in the first direction A, namely, one end of each tube10, and the second header30bmay communicate with ends of the tubes10directed in the second direction B, namely, the other end of each tube10.

However, the arrangement of the header30aand30band the tubes10is not limited to the above structure.

Each of the first and second headers30aand30bmay include main headers40and a sub-header50.

The main headers40may be respectively coupled to opposite ends of a plurality of tube arrays100so as to interconnect the tube arrays100for formation of one tube assembly200.

The main headers40may be made of a polymeric material.

The main headers40may be injection molded so as to be coupled to the opposite ends of the tube arrays100. Specifically, each of the main headers40may be formed around the outer sides of the corresponding connection members12by injection molding so as to form the tube assembly200.

The sub-header50may be coupled to outer sides of the main headers40so as to interconnect a plurality of tube assemblies200.

The sub-header50may be made of a polymeric material.

The sub-header50may be coupled to the outer sides of the main headers40so as to form a refrigerant flow passage70.

The refrigerant flow passage70serves as a chamber through which refrigerant supplied from the outside is supplied to the tubes10in a distributed manner.

The sub header50may include an inflow header51and an outflow header52. The inflow header51may be formed with an inlet51athrough which refrigerant is introduced toward the tubes10, and the outflow header52may be formed with an outlet52athrough which refrigerant is discharged from the tubes10.

The inflow header51may be provided at one of the first and second headers30aand30band the outflow header52may also be provided at the other of the first and second headers30aand30b, such that the inflow header51and the outflow header52are directed in different directions.

The tube assemblies200may have a stacked structure.

The tube assemblies200may have a vertically stacked structure.

When the tube assemblies200are vertically stacked, the refrigerant flow passage70may vertically guide the flow of refrigerant which sequentially flows through the tubes10. In addition, the inflow header51and the outflow header52may be vertically arranged. The outflow header52may be disposed above the inflow header51.

Both of the inflow header51and the outflow header52may be provided at either of the first header30aand the second header30bso as to be directed in the same direction.

As described above, the inflow header51may be provided at one of the first and second headers30aand30band the outflow header52may also be provided at the other of the first and second headers30aand30b, such that the inflow header51and the outflow header52are directed in different directions.

The cooling fins20on each tube10may be coupled to a surface of the tube10such that refrigerant flowing along the channel11of the tube10may efficiently exchange heat with ambient air.

The cooling fins20on each tube10may be arranged to be spaced apart from one another at regular intervals in a longitudinal direction of the tube10. The cooling fins20may be coupled to the outer peripheral surface of the tube10so as to serve to enlarge a contact area between ambient air and refrigerant flowing along the channel11of the tube10.

The cooling fins20may be made of a polymeric material.

The cooling fins20on each tube10may be injection molded integrally with the corresponding tube10.

The cooling fins20provided at a plurality of tubes10may be injection molded integrally with the tubes10and the connection members12to interconnect the tubes10.

The cooling fins20may have various shapes, and a detailed description thereof will be given below.

The heat exchanger1may further include air flow passages60along which ambient air moves.

Each of the air flow passages60may be formed between adjacent ones of the tube arrays100.

The air flow passage60may be arranged in a direction perpendicular to the longitudinal direction of the tubes10in the adjacent tube arrays100. That is, the flow of ambient air moving along the air flow passage60may be perpendicular to the flow of refrigerant flowing along the channels11in the adjacent tube arrays100.

FIG. 4is an enlarged view illustrating a coupling structure between the connection members and one main header of the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in this drawing can be seen fromFIGS. 1 to 3.

As shown inFIG. 4, the main header40may be coupled to the outer sides of the connection members12so as to form one tube assembly200.

Each of the connection members12may be formed, at an outer surface thereof, with at least one refrigerant leakage prevention groove13recessed inward of the connection member12.

The refrigerant leakage prevention groove13may be formed along an outer peripheral surface of the connection member12so as to form a closed loop in a longitudinal direction of the corresponding connection member12.

The refrigerant leakage prevention groove13may be coupled to an insertion protrusion portion41protruding from the main header40. The insertion protrusion portion41may have a closed loop shape corresponding to the refrigerant leakage prevention groove13.

Through coupling of the refrigerant leakage prevention groove13and the insertion protrusion portion41, the connection member12may be securely coupled to the main header40and, as such, refrigerant may be hermetically maintained.

The insertion protrusion portion41may be formed by filling the refrigerant leakage prevention groove13of the connection member12with an injection molded product during the injection molding process of the main header40.

FIG. 5is a view illustrating a process of coupling one main header and one sub-header of the heat exchanger according to the embodiment of the present invention.

As shown inFIG. 5, the sub-header50may be coupled to the outer side of the main header40to form the refrigerant flow passage70.

Coupling portions45of the main header40and the sub-header50may be formed along edges of the main header40and the sub-header50.

A coupling method of the main header40and the sub-header50may include a thermal bonding method or an induction heating method. Specifically, the thermal bonding method is a method of bonding the main header40and the sub-header50by simultaneously fusing and pressing the coupling portions45with a thermal bonding jig (not shown) having a temperature equal to or greater than melting points of the main header40and the sub-header50. The induction heating method is a method of bonding the main header40and the sub-header50by inserting a metal member (not shown) between the coupling portions45and then inducing an external magnetic field or an external electric field.

The refrigerant leakage may be prevented by securely coupling the main header40and the sub-header50.

FIGS. 6A and 6Eare views illustrating various shapes of the cooling fins of the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in these drawings can be seen fromFIGS. 1 to 3. In addition, redundant description thereof will be omitted.

As shown inFIGS. 6A to 6D, the cooling fins20may be provided at the outer peripheral surface of each tube10.

The cooling fins20may have an annular shape.

The cooling fins20on each tube10may be arranged to be spaced along the outer peripheral surface of the tube10in the longitudinal direction of the tube10.

The cooling fins20may have an annular shape inclined on the basis of a perpendicular direction X to the tubes10.

The cooling fins20may be variously inclined.

For convenience of description, it is assumed that a plurality of cooling fins20includes first cooling fins21and second cooling fins22. Each of the first cooling fins21has an annular shape inclined toward one end of the tube10formed with the first cooling fins21in the first direction A on the basis of the perpendicular direction X to the tube10, whereas each of the second cooling fins22has an annular shape inclined toward the other end of the tube10formed with the second cooling fins22in the second direction B on the basis of the perpendicular direction X to the tube10(seeFIG. 6B).

The first and second cooling fins21and22may be provided at the surface of each tube10to form at least one intersection point. For example, the first and second cooling fins21and22on each tube10may intersect in an “X-shape” to form one intersection point (seeFIG. 6C).

For convenience of description, it is assumed that a plurality of tubes10includes a first tube14and a second tube15adjacent thereto. First cooling fins21may be provided at an outer peripheral surface of the first tube14, and second cooling fins22may be provided at an outer peripheral surface of the second tube15. Ends21aand22aof the first and second cooling fins21and22facing each other may be alternately arranged in the longitudinal direction of the tubes10(seeFIG. 6D).

Meanwhile, as shown inFIG. 6E, the cooling fins20may be removed from the outer peripheral surface of each tube10(seeFIG. 6E).

However, when the cooling fins20are provided at the surface of each tube10, a contact area between ambient air and refrigerant flowing along the channel11of the tube10is increased and a turbulent flow is accelerated by the cooling fins20. Therefore, it may be possible to expect an improvement in heat exchange performance of 20˜25%, compared to removal of the cooling fins20.

Particularly, as shown inFIG. 6B, when the ends21aand22aof the first and second cooling fins21and22facing each other are alternately arranged, the contact area between ambient air and refrigerant is large and thermal resistance in the contact area is small. Thereby, a maximum improvement in heat exchange performance may be obtained.

The cooling fins20may have a semispherical shape protruding outward of each tube10.

The cooling fins20may have various shapes, but the present invention is not limited thereto.

FIG. 7is a perspective view illustrating a coupled state of pipes to the heat exchanger according to the embodiment of the present invention.FIG. 8is a perspective view illustrating one pipe coupled to the heat exchanger according to the embodiment of the present invention.FIG. 9is an enlarged cross-sectional view illustrating a coupling structure of one pipe and the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in these drawings can be seen fromFIGS. 1 to 3. In addition, redundant description thereof will be omitted.

As shown inFIGS. 7 to 9, the heat exchanger1may further include a pipe80coupled to at least one of the inlet51aand the outlet52a.

The pipe80may be made of a material different from the sub-header50.

The pipe80may be made of a copper (Cu) material.

When the heat exchanger1is used as an evaporator, liquid phase or gas phase refrigerant, having low-temperature and low-pressure, passing through an expansion valve (not shown) may be introduced into a first pipe81coupled to the inlet51a. The refrigerant introduced into the first pipe81may be evaporated by absorbing heat from the outside during passage through the tubes10, and be discharged to the outside through a second pipe82coupled to the outlet52a.

On the contrary, when the heat exchanger1is used as a condenser, high-temperature and high-pressure gas phase refrigerant passing through a compressor (not shown) may be introduced through a second pipe82. The refrigerant may be condensed by emitting heat to the outside during passage through the tubes10, and the condensed refrigerant may then be discharged to the outside through a first pipe81.

The pipe80may be inserted into the sub-header50during injection molding thereof to be integrally formed with the sub-header50.

At least one leakage prevention ring83may be disposed between the pipe80and the sub-header50in order to prevent refrigerant from leaking between the pipe80and the sub-header50.

The leakage prevention ring83may be made of a material capable of resisting high-temperature heat generated during the injection molding of the sub-header50.

The leakage prevention ring83may be made of a silicone or rubber material.

The pipe80may include a body84and a neck85.

The body84may have a hollow cylindrical shape, and therein have a passage84ain which refrigerant flows.

The neck85may be connected to one end of the body84so as to be coupled to at least one of the inlet51aand the outlet52a, and have a diameter different from the body84.

The neck85may have a larger diameter than the body84.

The diameter of the neck85may be reduced with decreasing distance to the body84. That is, the neck85may have a funnel shape having an increasing diameter with increasing distance from the body84.

The leakage prevention ring83may be disposed on an outer peripheral surface of the body84so as to be close to the neck85.

The leakage prevention ring83may have an annular shape so as to be disposed along the outer peripheral surface of the body84.

The sub-header50may include a protrusion portion53protruding outward thereof so as to provide the inlet51aand the outlet52a.

The body84may be coupled to at least one of the inlet51aand the outlet52asuch that the leakage prevention ring83is located inside the protrusion portion53.

When the sub-header50is injection molded in a state in which the leakage prevention ring83is disposed on the outer surface of the pipe80, the sub-header50presses the leakage prevention ring83by contraction during the injection molding process of the sub-header50, thereby enabling refrigerant to be hermetically maintained.

FIG. 10is a flowchart illustrating a method of manufacturing the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in this drawing can be seen fromFIGS. 1 to 3.

As shown inFIG. 10, a method of manufacturing the heat exchanger1may include forming tube arrays100(S1), forming tube assemblies200(S2), and coupling main headers40and a corresponding sub-header50(S3).

Specifically, one tube array100may be formed by integrally injection molding a plurality of tubes10and connection members12respectively coupled to opposite ends of the tubes10.

A plurality of cooling fins20on each tube10may be injection molded integrally with the tube10and the corresponding connection members12so as to be disposed on an outer peripheral surface of the tube10.

The tube array100may be injection molded such that at least one refrigerant leakage prevention groove13recessed inward of each connection member12is formed on an outer surface of the connection member12.

One tube assembly200may be formed by inserting a plurality of tube arrays100arranged in parallel between the main headers40and injection molding the main headers40together with the tube arrays100.

The tube arrays100and the main headers40may be made of polymeric materials different from each other.

The main headers40may be respectively located at opposite ends of a plurality of tube arrays100.

The sub-header50may be injection molded by inserting a pipe80, in which refrigerant flows, into the sub-header50. Specifically, the sub-header50may be injection molded by inserting the pipe80thereinto such that a portion of the pipe80is located outside the sub-header50, namely, such that a portion of the pipe80is exposed to the outside.

The sub-header50may be coupled to outer sides of the main headers40so as to form a refrigerant flow passage70by coupling with the main headers40.

The coupling method of the main header40and the sub-header50may include a thermal bonding method or an induction heating method.

FIGS. 11A and 11Bare views illustrating a process of manufacturing one tube array of the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in this drawing can be seen fromFIGS. 1 to 3.

As shown inFIGS. 11A and 11B, the tube array100may be formed by a first mold apparatus300.

The first mold apparatus300may include a first mold310, a second mold320, a third mold330, and a fourth mold340. The first mold310is located at an upper side and the second mold320is located at a lower side. The third mold330is located at a left side and the fourth mold340is located at a right side. The first, second, third, and fourth molds310,320,330, and340are coupled to one another so as to form a first molding space350.

The first and second molds310and320may be coupled to each other so as to form shapes of a plurality of tubes10in each tube array100.

The first and second molds310and320may be coupled to each other so as to integrally form shapes of the tubes10and a plurality of cooling fins20provided at each of the tubes10.

The third and fourth molds330and340may be coupled to the first and second molds310and320so as to form respective shapes of the connection members12.

A piston core360may be inserted into the first molding space350such that the channel11for movement of refrigerant is formed within each of the tubes10. The piston core360may pass through the fourth mold340and be inserted into the first molding space350such that one end of the piston core360comes into contact with an inner surface of the third mold330.

When the piston core360is inserted into the first molding space350, resin is injected into the first molding space350through a plurality of resin gates370.

After a predetermined time passes, the first, second, third, and fourth molds310,320,330, and340are separated from one another and the piston core360is finally separated from the first molding space350, so as to take the polymeric tube array100out of the first molding space350.

The piston core360may be separated from the first molding space350using an air cylinder380.

Protrusion portions (not shown) protruding toward the first molding space350may be provided at inner surfaces of the third and fourth molds330and340. The protrusion portions provided at the third and fourth molds330and340may form at least one refrigerant leakage prevention groove13at each of the connection members12. That is, each of the protrusion portions may have a shape corresponding to the refrigerant leakage prevention groove13.

FIGS. 12A and 12Bare views illustrating a process of manufacturing one tube assembly of the heat exchanger according to the embodiment of the present invention. Reference numerals not shown in this drawing can be seen fromFIGS. 1 to 3.

As shown inFIGS. 12A and 12B, the tube assembly200may be formed by a second mold apparatus400.

The second mold apparatus400may include a fifth mold (not shown), a sixth mold420, a seventh mold430, and an eighth mold440. The fifth mold (not shown) is located at an upper side and the sixth mold420is located at a lower side. The seventh mold430is located at a left side and the eighth mold440is located at a right side. The fifth mold (not shown), the sixth mold420, the seventh mold430, and the eighth mold440are coupled to one another so as to form a second molding space450.

The injection molded tube arrays100are arranged in parallel and are inserted into the second molding space450.

When the tube arrays100are inserted into the second molding space450, resin is injected into the second molding space450through a plurality of resin gates470such that the main headers40are formed at opposite ends of the tube arrays100.

After a predetermined time passes, the fifth mold (not shown), the sixth mold420, the seventh mold430, and the eighth mold440are separated from one another and the piston core360is finally separated from the first molding space350, so as to take the tube assembly200out of the second molding space450.

FIG. 13is a flowchart illustrating a method of manufacturing the heat exchanger according to another embodiment of the present invention. Reference numerals not shown in these drawings can be seen fromFIGS. 1 to 3. In addition, redundant description ofFIG. 10will be omitted.

As shown inFIG. 13, a method of manufacturing the heat exchanger1may include forming tube arrays100(T1), forming tube assemblies200(T2), coupling a sub-header50and a pipe80(T3), and coupling main headers40and the sub-header50(T4).

The sub-header50may be injection molded of a polymeric material.

The pipe80may be inserted into the sub-header50during injection molding of the sub-header50such that the pipe80is connected to at least one of an inlet51aand an outlet52aprovided at the sub-header50.

The sub-header50may be injection molded by inserting the pipe80into the sub-header50in a state in which at least one leakage prevention ring83is disposed on an outer peripheral surface of the pipe80in order to prevent refrigerant from leaking between the pipe80and the sub-header50. In this case, injection molding conditions of the sub-header50may be adjusted so as not to damage the leakage prevention ring83.

Although the embodiment in which the headers30aand30bare coupled to the tube assemblies200has been described above, an embodiment in which the headers30aand30bare coupled to the tube arrays100may also be performed. That is, the main headers40may be respectively coupled to opposite ends of each tube array100including the tubes10, and the sub-headers50may be coupled to the outer sides of the main headers40to form one refrigerant flow passage70.

The heat exchanger1according to the present invention may be applied to various electronic apparatuses including a refrigerator and an air conditioner.