Patent Description:
Generally, a heat exchanger may be used as a condenser or an evaporator in a refrigerating cycle device including a compressor, a condenser, an expansion mechanism, and an evaporator.

Further, the heat exchanger is installed in a vehicle, a refrigerator or the like to exchange heat between refrigerant and air.

The heat exchanger may be classified into a fin tube type heat exchanger, a micro channel type heat exchanger, and the like, according to the structure.

Recently, copper is replaced by aluminum as a material for the heat exchanger in view of cost, processability, and corrosion resistance. This is because aluminum is light, inexpensive, and has high thermal conductivity.

The aluminum material for the heat exchanger mainly use pure aluminum (A1XXX) that is advantageous in extrusion, has high thermal conductivity, and is inexpensive, and aluminum-manganese (A3XXX) that is slightly lower in extrudability than the pure aluminum but has relatively high strength and corrosion resistance.

Table <NUM> shows the compositions of A1070 and A3003, which are mainly used as a conventional aluminum material for a heat exchanger. A1070 is pure aluminum material, while A3003 is aluminum- manganese material.

The A1070 material is low in material cost and extrusion cost, so that it is used as a tube and fin material of a condenser for a home appliance, such as an air conditioner and a refrigerator, which does not require high strength but is important in economic efficiency. In contrast, the A3003 material is superior to the A1070 in strength and corrosion resistance but is slightly high in extrusion cost, so that it is used as an extruded tube and fin material for a heat exchanger such as an intercooler and a radiator for a vehicle.

On the other hand, aluminum is a metal that is easily activated but has high corrosion resistance by forming an oxide film on a surface in the atmosphere. However, pitting corrosion occurs in which corrosion occurs only in a local region where the oxide film is damaged when aluminum is corroded. Further, corrosion is intensively propagated to a portion by electrochemical action with various impurities contained in aluminum alloy. Due to the corrosion mechanism of aluminum, the aluminum heat exchanger may be locally penetrated, thus causing the leakage of refrigerant or high-temperature fluid therefrom.

In order to prevent the corrosion, Patent Document <NUM> has attempted to adjust the contents of copper, silicon, iron, and zirconium and use properties of zirconium elements that control a corrosion product and induce uniform corrosion.

However, Patent Document <NUM> is problematic in that zirconium is a very expensive rare metal, so that manufacturing cost is expensive, and the material loses corresponding characteristics during the recrystallization of elements in the material when fins and tubes are subjected to brazing welding at high temperature, so that it is difficult to use this technology in mass production.

Referring to <FIG>, according to the prior art, in order to prevent corrosion, there has been used a method of applying zinc particles <NUM> onto a tube <NUM> and brazing it with a fin <NUM>. The fin <NUM> is usually coated with cladding <NUM>.

However, as shown in <FIG> and <FIG>, in the process of melting the fin <NUM> and zinc, zinc concentration is not constant, thus leading to a section (portion of the tube <NUM> close to the fin <NUM>) in which the zinc concentration is excessive and a section in which the zinc concentration is insufficient. Further, the method of applying zinc has technical limitations in that quality deviation occurs in terms of accurate application amount and uniformity.

Therefore, as shown in <FIG>, the fin <NUM> and the tube <NUM> may be separated from each other in the section where the zinc concentration is excessive, and corrosion may start in the section where the zinc concentration is low.

Patent Document <NUM> - <CIT> <CIT>), which discloses the preamble of claim <NUM>, relates to an aluminum cladding material comprising an aluminum alloy core material and a sacrificial anode material layer cladded on at least one surface of the aluminum alloy core material.

<CIT>) relates to an aluminum alloy which is excellent in extrudability and intergranular corrosion resistance which is used for the extruded small-bore hollow flat tubes which form parts of an aluminum heat exchanger.

An objective of the present invention provides a heat exchanger that uses a sacrificial sheet having a potential difference, thus preventing the corrosion of a fin and a tube and preventing the fin from being separated from the tube.

Another objective of the present invention provides a heat exchanger that uses a sacrificial sheet on an outer surface of a tube, thus enabling easy manufacture and reducing manufacturing cost.

A further objective of the present invention provides a heat exchanger, in which a sacrificial sheet can be easily aligned and coupled to an outer surface of a tube.

The objectives to be achieved by the present invention are not limited to the above-mentioned objectives, and other objectives which are not mentioned will be clearly understood by those skilled in the art from the following description.

The invention is specified by the independent claim. A heat exchanger according to the present invention is characterized in that a corrosion potential of a sacrificial sheet between a fin and a refrigerant tube is lower than that of the refrigerant tube.

Further, a heat exchanger according to the present disclosure is characterized in that the sacrificial sheet between the fin and the refrigerant tube is zinc.

To be more specific, the present invention provides a heat exchanger including a plurality of refrigerant tubes through which refrigerant flows, a fin disposed between adjacent refrigerant tubes to conduct heat, and a sacrificial sheet configured such that a first surface thereof contacts the refrigerant tube and a second surface thereof contacts the fin. A corrosion potential of the sacrificial sheet is lower than a corrosion potential of the refrigerant tube.

The corrosion potential of the sacrificial sheet may be lower than a corrosion potential of the fin.

The corrosion potential of the fin may be lower than the corrosion potential of the refrigerant tube.

The sacrificial sheet may include zinc or alloy of zinc and aluminum.

The fin may include at least one of aluminum, copper and aluminum alloy.

The refrigerant tube may include at least one of aluminum, copper and aluminum alloy.

The sacrificial sheet may be positioned on each of upper and lower surfaces of the refrigerant tube.

The sacrificial sheet may include a first region, and a second region with a step between the first region and the second region.

The second region may be formed by drawing a portion of the first region.

The second region may protrude toward the refrigerant tube contacting the sacrificial sheet.

The second region may be formed by recessing a portion of the first region.

The refrigerant tube may include a matching portion corresponding to the second region.

A width of the first region may be greater than a width of the second region.

A thickness of the sacrificial sheet is thicker than a thickness of the fin.

A thickness of the refrigerant tube is thicker than a thickness of the sacrificial sheet.

Each of the refrigerant tubes may include a plurality of micro channels therein.

The heat exchanger may further include a header coupled to first ends of the plurality of refrigerant tubes to supply the refrigerant into the plurality of refrigerant tubes.

The material of the sacrificial sheet may be different from that of the fin and the refrigerant tube.

The above and other objectives, features, and advantages of the present disclosure will be easily understood from the following preferred embodiments in conjunction with the accompanying drawings. However, the disclosure may be embodied in different forms without being limited to the embodiments set forth herein. Rather, the embodiments disclosed herein are provided to make the disclosure thorough and complete and to sufficiently convey the scope of the present disclosure to those skilled in the art. Like reference numerals refer to like parts throughout various figures and embodiments of the present disclosure.

The spatially relative terms "below", "beneath", "lower", "above", "upper", etc. may be used to easily describe a relationship between one component and another component as shown in the drawings. The spatially relative terms should be understood as encompassing different directions of components in use or operation in addition to directions shown in the drawings. For example, when reversing components shown in the drawings, components described as being "below" or "beneath" other components may be placed "above" the other components. Thus, the exemplary term "below" may include directions of both below and above. The components may also be oriented in other directions, and thus the spatially relative terms may be interpreted according to an orientation.

In the present disclosure, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprise", "include", "have", etc. when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or combinations of them but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or combinations thereof.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs.

The size or shape of components shown in the drawings may be exaggerated for the clarity and convenience of description. Further, the size and area of each component do not entirely reflect the actual size and area.

Further, angles and directions mentioned in the process of describing the structure of the embodiment are based on those described in the drawings. In the description of the structure according to the embodiment in the specification, if the reference point and the positional relationship for the angle are not clearly mentioned, refer to the related drawings.

<FIG> is a diagram illustrating a refrigerating cycle device according to an embodiment of the present disclosure, and <FIG> is a perspective view illustrating the outside of an outdoor unit shown in <FIG>.

Referring to <FIG> and <FIG>, the refrigerating cycle device according to this embodiment may include a compressor <NUM> that compresses a refrigerant, an outdoor heat exchanger <NUM> that exchanges heat between the refrigerant and outdoor air, an expansion mechanism <NUM> that expands the refrigerant, and an indoor heat exchanger <NUM> that exchanges heat between the refrigerant and indoor air.

The refrigerant compressed by the compressor <NUM> may be condensed by exchanging heat with outdoor air while passing through the outdoor heat exchanger <NUM>.

The outdoor heat exchanger <NUM> may be used as a condenser.

The refrigerant condensed in the outdoor heat exchanger <NUM> may flow to the expansion mechanism <NUM> and then be expanded. The refrigerant expanded by the expansion mechanism <NUM> may be evaporated by exchanging heat with indoor air while passing through the indoor heat exchanger <NUM>.

The indoor heat exchanger <NUM> may be used as an evaporator that evaporates the refrigerant. The refrigerant evaporated by the indoor heat exchanger <NUM> may be recovered to the compressor <NUM>.

The heat exchanger may include the indoor heat exchanger <NUM> and the outdoor heat exchanger <NUM>.

The refrigerant is operated in a refrigerating cycle while circulating through the compressor <NUM>, the outdoor heat exchanger <NUM>, the expansion mechanism <NUM>, and the indoor heat exchanger <NUM>.

An intake path of the compressor <NUM> that guides the refrigerant passing through the indoor heat exchanger <NUM> to the compressor <NUM> may be connected to the compressor <NUM>. An accumulator <NUM> in which a liquid refrigerant is accumulated may be installed in the intake path of the compressor <NUM>.

The indoor heat exchanger <NUM> may form a refrigerant path through which the refrigerant passes.

The refrigerating cycle device may be a separable type air conditioner in which an indoor unit I and an outdoor unit O are separated. In this case, the compressor <NUM> and the outdoor heat exchanger <NUM> may be installed in the outdoor unit I. Further, the refrigerating cycle device may be a refrigerator, and the indoor heat exchanger <NUM> may be disposed to exchange heat with air inside a food storage, and the outdoor heat exchanger <NUM> may exchange heat with air outside the food storage. In the case of the refrigerator, the indoor unit I and the outdoor unit O may be disposed together in a main body.

The expansion mechanism <NUM> may be installed in either of the indoor unit I or the outdoor unit O.

The indoor heat exchanger <NUM> may be installed in the indoor unit I.

An outdoor fan <NUM> may be installed in the outdoor unit O to blow outdoor air to the outdoor heat exchanger <NUM>. In addition, the compressor <NUM> may be installed in a machine room of the outdoor unit O.

An indoor fan <NUM> may be installed in the indoor unit I to blow indoor air to the indoor heat exchanger <NUM>.

In the conventional heat exchange, a liquid phase and a gas phase of the refrigerant are mixed. When the two-phase refrigerant flowing into a header is introduced into a refrigerant tube, the gas phase and the liquid phase may be unevenly introduced.

In order to solve the problem, a heat exchanger <NUM> according to the present disclosure will be described in detail.

<FIG> is a perspective view illustrating a heat exchanger according to an embodiment of the present disclosure, <FIG> is a longitudinal sectional view of the heat exchanger shown in <FIG>, and <FIG> is a sectional view taken along line <NUM>-<NUM>' of <FIG>.

Referring to <FIG>, the heat exchanger <NUM> is a device that exchanges heat between the refrigerant of a refrigerating cycle and outside air. Preferably, the heat exchanger <NUM> evenly distributes the refrigerant therein, and has a large heat transfer area.

The heat exchanger <NUM> may be arranged with a plurality of rows, and the flow direction of the refrigerant in one row may be alternately changed.

For example, the heat exchanger <NUM> includes a plurality of refrigerant tubes <NUM> through which the refrigerant flows, a fin <NUM> disposed between adjacent refrigerant tubes <NUM> to conduct heat, and a sacrificial sheet <NUM> configured such that one surface thereof contacts the refrigerant tube <NUM> and the other surface contacts the fin <NUM>.

The heat exchanger <NUM> further includes a header <NUM> to which one end of each of the plurality of refrigerant tubes <NUM> is coupled to supply the refrigerant into the refrigerant tubes <NUM>, an outer pipe <NUM> provided inside the header <NUM>, and an inner pipe <NUM> provided inside the outer pipe <NUM>.

The refrigerant tube <NUM> has a fine inner diameter so that the refrigerant flows therein to maximize a contact area with the air. The plurality of refrigerant tubes <NUM> are connected to the header <NUM>. The refrigerant tubes <NUM> extend in a direction transverse to the header <NUM>.

To be more specific, the refrigerant tubes <NUM> may be arranged long in a horizontal (front-rear) direction (LeRi), and the plurality of refrigerant tubes <NUM> may be stacked in a vertical (longitudinal) direction (UD). While air passes through a space between the plurality of refrigerant tubes <NUM> stacked in the vertical direction, the air exchanges heat with the refrigerant in the refrigerant tubes <NUM>. The plurality of refrigerant tubes <NUM> stacked horizontally define a heat exchange surface together with the fins <NUM> that will be described later.

The refrigerant tube <NUM> may include a plurality of micro channels 50a therein. The plurality of micro channels 50a defines a space through which the refrigerant passes. The plurality of micro channels 50a may extend in parallel with the refrigerant tube <NUM>.

To be more specific, as shown in <FIG>, the sectional shape of the refrigerant tube <NUM> may be a rectangular shape whose horizontal length is greater than a vertical length, and the sectional shape of the micro channel 50a may be a rectangular shape.

The micro channels 50a are usually stacked in one row in a direction (front-rear direction) FR crossing the longitudinal direction of the refrigerant tube <NUM>.

The fin <NUM> transfers heat from the refrigerant tube <NUM>. The fin <NUM> increases the contact area with air to improve heat dissipation performance.

The fin <NUM> is disposed between adjacent refrigerant tubes <NUM>. The fin <NUM> may have various shapes, but may be formed by bending a plate that has the same width as the refrigerant tube <NUM>. The fin <NUM> may be coated by cladding <NUM>.

The fin <NUM> may connect two refrigerant tubes <NUM> stacked in the vertical direction to conduct heat. The fin <NUM> may directly contact the refrigerant tube <NUM>, and may be connected to the refrigerant tube <NUM> by the sacrificial sheet <NUM>.

When seen from the front-rear direction, a contact portion between the fin <NUM> and the sacrificial sheet <NUM> is formed in a U- or V-shape.

The fins <NUM> and the refrigerant tubes <NUM> are alternatively stacked in the vertical direction, and the refrigerant tubes <NUM> are positioned at the lowermost end and the uppermost end of the fin <NUM>. The refrigerant tubes <NUM> are connected to the upper end of the fin <NUM> and the lower end of the fin <NUM>.

Assuming that the refrigerant tube <NUM> located at the uppermost end is defined as a first refrigerant tube <NUM> or <NUM> and the refrigerant tube <NUM> located under the first refrigerant tube <NUM> or <NUM> is defined as a second refrigerant tube <NUM> or <NUM>, the fin <NUM> between the first refrigerant tube <NUM> or <NUM> and the second refrigerant tube <NUM> or <NUM> may be defined as a first fin <NUM> or <NUM>. In this way, an nth refrigerant tube and an nth fin may be defined.

The header <NUM> may be coupled to one end of each of the plurality of refrigerant tubes <NUM> to supply the refrigerant into the plurality of refrigerant tubes <NUM>. Further, the header <NUM> may be coupled to one end of the refrigerant tube <NUM> to collect the refrigerant discharged from the refrigerant tube <NUM> and supply the collected refrigerant to another device.

The header <NUM> has a diameter, inner diameter, or size larger than that of the refrigerant tubes <NUM>, and extends in the vertical direction. The header <NUM> may include a left header <NUM> connected to one end of the refrigerant tube <NUM>, and a lower header <NUM> or <NUM> connected to the other end of the refrigerant tube <NUM>.

The right header <NUM> communicates with right sides of the plurality of refrigerant tubes <NUM>. The right header <NUM> extends long in the vertical direction, and is connected to an inlet pipe <NUM>. The interior of the right header <NUM> is formed as one space, so that the refrigerant introduced through the inlet pipe <NUM> is distributed and supplied to the plurality of refrigerant tubes <NUM>. The inlet pipe <NUM> is an example of a refrigerant supply unit.

The inlet pipe <NUM> is connected to a region adjacent to the lower end of the right header <NUM>.

The left header <NUM> communicates with the left sides of the plurality of refrigerant tubes <NUM>. The left header <NUM> extends long in the vertical direction, and is connected to an outlet pipe <NUM>. The interior of the left header <NUM> is formed as one space to guide the refrigerant, discharged to the upper side of the plurality of refrigerant tubes <NUM>, to the outlet pipe <NUM>.

Of course, the refrigerant discharged from the left header <NUM> may be supplied to the header <NUM> of another heat exchanger <NUM>.

In the heat exchanger <NUM>, the outer pipe <NUM> and the inner pipe <NUM> may be positioned to prevent the refrigerant from being biased inside the header <NUM>. The refrigerant is uniformly distributed through holes of the outer pipe <NUM> and the inner pipe <NUM>.

<FIG> is a sectional perspective view of <FIG>, and <FIG> is an enlarged view of a portion of <FIG>.

Referring to <FIG> and <FIG>, one surface of the sacrificial sheet <NUM> contacts the refrigerant tube <NUM>, and the other surface contacts the fin <NUM>, so that the sacrificial sheet is corroded instead of the fin <NUM> and the refrigerant tube <NUM>, thus suppressing the corrosion of the fin <NUM> and the refrigerant tube <NUM> and preventing the separation of the fin <NUM> from the refrigerant tube <NUM>.

For example, the corrosion potential of the sacrificial sheet <NUM> may be lower than the corrosion potential of the refrigerant tube <NUM>. If corrosion occurs while two metals contact each other, the metal with the lower corrosion potential is corroded first, so that the sacrificial sheet <NUM> is corroded instead of the refrigerant tube <NUM>, thus preventing the refrigerant tube <NUM> from corroding and preventing the refrigerant from leaking out.

Further, the corrosion potential of the sacrificial sheet <NUM> may be lower than the corrosion potential of the fin <NUM>. Even if only the refrigerant tube <NUM> is not corroded, the leakage of the refrigerant is prevented. However, when the fin <NUM> is corroded, the flow of air is hindered and the efficiency of the refrigerant is lowered. Thus, the corrosion potential of the sacrificial sheet <NUM> is preferably lower than the corrosion potential of the fin <NUM>.

If the corrosion potential of the sacrificial sheet <NUM> is lower than the corrosion potential of the fin <NUM>, the sacrificial sheet <NUM> is corroded first instead of the fin <NUM>, thus preventing the fin <NUM> from being corroded.

Preferably, the corrosion potential of the fin <NUM> may be lower than the corrosion potential of the refrigerant tube <NUM>. Among the fin <NUM> and the refrigerant tube <NUM>, a dangerous part when corrosion occurs is the refrigerant tube <NUM>. When the fin <NUM> is corroded, efficiency may be slightly lowered. However, when the refrigerant tube <NUM> is corroded, the refrigerant leaks out and the air conditioner is not operated, causing a major problem.

Therefore, according to the present disclosure, the corrosion potential of the fin <NUM> is set to be lower than the corrosion potential of the refrigerant tube <NUM>, so that the fin <NUM> is corroded prior to the refrigerant tube <NUM>, thus preventing the corrosion of the refrigerant tube <NUM>.

In conclusion, the corrosion potential of the sacrificial sheet <NUM> may be lower than the corrosion potential of the refrigerant tube <NUM>, the corrosion potential of the sacrificial sheet <NUM> may be lower than the corrosion potential of the fin <NUM>, and the corrosion potential of the fin <NUM> may be lower than the corrosion potential of the refrigerant tube <NUM>.

To be more specific, the corrosion potential of the sacrificial sheet <NUM> may range from - <NUM>. 97V to - <NUM>. 1V, the corrosion potential of the fin <NUM> may range from -<NUM>. 75V to - <NUM>. 95V, and the corrosion potential of the refrigerant tube <NUM> may range from -<NUM>. 6V to - <NUM>.

Further, the corrosion potential of the sacrificial sheet <NUM> may be lower than the corrosion potential of the fin <NUM>, or may be lower than the corrosion potential of the refrigerant tube <NUM>.

The material of the sacrificial sheet <NUM> may be different from the material of the fin <NUM> and the material of the refrigerant tube <NUM>. The material of the sacrificial sheet <NUM> may include metal or alloy that satisfies the corrosion potential. Considering cost, the ease of manufacture, thermal conductivity, etc., the sacrificial sheet <NUM> preferably includes zinc or an alloy of zinc and aluminum. However, the material of the sacrificial sheet <NUM> is not limited thereto.

The material of the fin <NUM> may include metal or alloy that satisfies the corrosion potential. Considering cost, the ease of manufacture, thermal conductivity, etc., the fin <NUM> preferably includes at least one of aluminum, copper, and aluminum alloy. However, the material of the fin <NUM> is not limited thereto.

The material of the refrigerant tube <NUM> may include metal or alloy that satisfies the corrosion potential. Considering cost, the ease of manufacture, thermal conductivity, etc., the refrigerant tube <NUM> preferably includes at least one of aluminum, copper, and aluminum alloy. However, the material of the refrigerant tube <NUM> is not limited thereto.

The sacrificial sheet <NUM> is positioned on the upper surface and/or lower surface of the refrigerant tube <NUM>. The sacrificial sheet <NUM> is in surface contact with the upper surface and/or lower surface of the refrigerant tube <NUM>. Preferably, the sacrificial sheet <NUM> may cover the entire upper surface and/or lower surface of the refrigerant tube <NUM>.

The width of the sacrificial sheet <NUM> in the front-rear direction may be at least equal to the width of the fin <NUM> and the refrigerant tube <NUM> or larger than the width of the fin <NUM> and the refrigerant tube <NUM>. This is because when the width of the sacrificial sheet <NUM> is reduced, corrosion first occurs in a portion where the sacrificial sheet <NUM> is not present.

The sacrificial sheet <NUM> may have a structure that enhances a coupling force with the refrigerant tube <NUM> and facilitates alignment with the refrigerant tube <NUM>.

For example, the sacrificial sheet <NUM> may include a first region <NUM> and a second region <NUM> with a step between the first region <NUM> and the second region. The width of the first region <NUM> may be greater than that of the second region <NUM>.

The second region <NUM> is a region having a height difference from the first region <NUM>. For example, the second region <NUM> may be formed by drawing a portion of the first region <NUM>. The second region <NUM> may protrude toward the refrigerant tube <NUM> contacting the sacrificial sheet <NUM>. As another example, the second region <NUM> may be formed by recessing a portion of the first region <NUM>.

The second region <NUM> may be continuously or intermittently formed in the longitudinal direction (left-right direction) of the refrigerant tube <NUM>. The second region <NUM> may be continuously or intermittently formed in the width direction (front-rear direction) of the refrigerant tube <NUM>.

The refrigerant tube <NUM> may further include a matching portion 50b corresponding to the second region <NUM>. The matching portion 50b is a portion matched with the second region <NUM>. The matching portion 50b may be inserted into the second region <NUM> or may be a space into which the second region <NUM> is inserted. Preferably, the matching portion 50b may be configured as a groove.

The thickness T3 of the sacrificial sheet <NUM> is thicker than the thickness T1 of the fin <NUM>. The thickness of the refrigerant tube <NUM> is thicker than the thickness T3 of the sacrificial sheet <NUM>.

If the thickness T3 of the sacrificial sheet <NUM> is too thin, it is rapidly corroded, thus shortening the lifespan of the heat exchanger. If the thickness T2 of the sacrificial sheet <NUM> is too thick, cost burden increases and thermal conductivity also deteriorates.

Therefore, the thickness T2 of the sacrificial sheet <NUM> preferably has a value between the thickness T1 of the fin <NUM> and the thickness T3 of the refrigerant tube <NUM>.

The heat exchanger of the present disclosure has one or more of the follow effects.

First, the present disclosure is advantageous in that a sacrificial sheet disposed between a fin and a refrigerant tube has a low corrosion potential, so that the sacrificial sheet is corroded prior to the refrigerant tube and the fin by external water or air, thus preventing the corrosion of the fin and the tube and preventing the fin from being separated from the tube.

Second, the present disclosure is advantageous in that a sacrificial sheet covers both the upper and lower surfaces of a refrigerant tube to have a thick thickness, so that it can withstand corrosion for a long time, and consequently, sacrificial corrosion is performed for a long time, thus increasing the lifespan of a heat exchanger.

Third, the present disclosure is advantageous in that a sacrificial sheet is attached to an outer surface of a refrigerant tube, and a fin is brazed on the sacrificial sheet, so that it facilitates manufacture, reduces manufacturing time, and reduces manufacturing cost compared to brazing by applying zinc particles, and zinc concentration around the fin becomes uniform.

Fourth, the present disclosure is advantageous in that a region of a sacrificial sheet is inserted into a groove of a refrigerant tube, so that the refrigerant tube and the sacrificial sheet are easily aligned, and the separation of the refrigerant tube from the sacrificial sheet is prevented.

Claim 1:
A heat exchanger comprising:
a plurality of refrigerant tubes (<NUM>, <NUM>, <NUM>) through which refrigerant flows;
a fin (<NUM>, <NUM>) disposed between adjacent refrigerant tubes (<NUM>, <NUM>, <NUM>) to conduct heat; and
a sacrificial sheet (<NUM>) configured such that a first surface thereof contacts the refrigerant tube (<NUM>, <NUM>, <NUM>) and a second surface thereof contacts the fin (<NUM>, <NUM>),
wherein a corrosion potential of the sacrificial sheet (<NUM>) is lower than a corrosion potential of the refrigerant tube (<NUM>, <NUM>, <NUM>),
characterized in that
a thickness of the sacrificial sheet (<NUM>) is thicker than a thickness of the fin (<NUM>, <NUM>), and
wherein a thickness of the refrigerant tube (<NUM>, <NUM>, <NUM>) is thicker than a thickness of the sacrificial sheet (<NUM>).