JP6772731B2 - How to make a heat exchanger - Google Patents

Description

The present invention relates to a method for manufacturing a heat exchanger.

Conventionally, heat exchangers having fins, a plurality of heat transfer tubes, and a header to which a plurality of heat transfer tubes are connected have been manufactured.

For example, in the heat exchanger described in Patent Document 1 (Japanese Unexamined Patent Publication No. 2013-92265), in order to maintain good adhesion between the fins and the heat transfer tube in the initial stage of manufacturing, the fins are first attached to the heat transfer tube. On the other hand, we propose a manufacturing method in which the fins and heat transfer tubes are temporarily fixed by welding and then fixed with an adhesive.

However, according to the method for manufacturing a heat exchanger of Patent Document 1, when the fins are temporarily fixed to the heat transfer tube by welding, the temperature of the heat transfer tube rises significantly, so that the heat transfer tube itself is located at the welded portion. There is a risk that the shape of the will be deformed.

If the heat transfer tube is deformed in this way, then when the deformed heat transfer tube is brazed or welded to the header, the connection portion of the plurality of heat transfer tubes and the connection opening of the header are aligned with each other. It can be difficult.

The present invention has been made in view of the above points, and an object of the present invention is a method for manufacturing a heat exchanger capable of simplifying the manufacturing work while suppressing deformation due to heat of the multi-hole tube. To provide.

The method for manufacturing a heat exchanger according to the first aspect is that the fins made of aluminum or an aluminum alloy, a plurality of multi-hole tubes made of aluminum or an aluminum alloy, and a plurality of multi-hole tubes are connected to each other. It is a method for manufacturing a heat exchanger having a common space forming member, and includes a first step and a second step. In the first step, the fins and the multi-hole tube are joined with an adhesive. In the second step, after the first step, the multi-hole pipe is brazed or welded to the common space forming member while performing a process of suppressing the temperature rise of the joint portion between the fin and the multi-hole pipe . In the first step, heating is performed to cure the adhesive. In the second step, the temperature of the brazed part or the welded part between the multi-hole pipe and the common space forming member becomes higher than the temperature of the adhesive whose temperature has risen due to heating for curing the adhesive. The temperature is raised to.

Here, the common space forming member is not particularly limited, and includes a member forming a space in which a plurality of flow paths such as a header, a branch pipe, and a collecting pipe used in a heat exchanger merge. Is done.

The adhesive used in the first step is not particularly limited, and includes an adhesive that is bonded at a temperature lower than the temperature required for brazing or welding in the second step.

Here, in brazing, a melted brazing material is arranged between the multi-hole pipe and the common space forming member, and both are joined. In welding, the joints of the multi-hole pipe and / or the common space forming member are melted to join the two.

Here, the treatment for suppressing the temperature rise of the joint portion between the fin and the multi-hole pipe is not particularly limited, but for example, when brazing or welding the multi-hole pipe and the common space forming member, the multi-hole pipe is used. It is a process of suppressing the influence of heating or temperature rise of the joint portion between the fin and the common space forming member on the temperature rise of the joint portion between the fin and the multi-hole pipe. For example, the common space forming member with the multi-hole pipe is irradiated with infrared rays. Use a light-shielding plate to prevent or block the infrared rays from reaching the joint between the fins and the multi-hole pipe when heating the connection point, and connect the multi-hole pipe and the common space forming member by high frequency. In the case of heating a portion, the use of a metal plate is included so as to suppress or block the high frequency from reaching the joint portion between the fin and the multi-hole tube.

In this method of manufacturing a heat exchanger, the fins and the multi-hole pipe are first joined with an adhesive in the first step, and then the multi-hole pipe and the common space forming member are brazed or welded in the second step. For this reason, since the fins and the multi-hole pipe are joined with an adhesive, it is possible to prevent the multi-hole pipe from being deformed by heat by a joining method such as brazing with heating, and the deformation is suppressed. Can be brazed or welded to the common space forming member, and the position of the multi-hole pipe and the connection destination of the common space forming member can be easily performed. Therefore, the work of brazing or welding the multi-hole pipe to the common space forming member can be easily performed.

Further, in the method of manufacturing this heat exchanger, when brazing or welding the multi-hole pipe and the common space-forming member, the heating or temperature rise of the joint portion between the multi-hole pipe and the common space-forming member causes the fin and the multi-hole pipe to rise. Since the influence on the joint portion with the fin can be suppressed, the deterioration of the adhesive for joining the fin and the multi-hole pipe due to the temperature can be suppressed.

Further, in this heat exchanger manufacturing method, the temperature of the brazed part or the welded part between the multi-hole pipe and the common space forming member at the time of brazing or welding is higher than the temperature for curing the adhesive. Therefore, the temperature of the adhesive for joining the fin and the multi-hole pipe tends to rise. However, even in this case, when the multi-hole pipe and the common space forming member are brazed or welded, the heating or temperature rise of the joint portion between the multi-hole pipe and the common space forming member causes the fin and the multi-hole pipe to rise. The influence on the joint portion can be suppressed. Therefore, even when the temperature of the brazed portion or the welded portion between the multi-hole pipe and the common space forming member is high, deterioration due to the temperature of the adhesive for joining the fin and the multi-hole pipe is suppressed. Will be possible.

The method for manufacturing the heat exchanger according to the second aspect is that the fins made of aluminum or aluminum alloy, a plurality of multi-hole tubes made of aluminum or aluminum alloy, and a plurality of multi-hole tubes connected to each other are made of aluminum or aluminum alloy. It is a method for manufacturing a heat exchanger having a common space forming member, and includes a first step and a second step. In the first step, the fins and the multi-hole tube are joined with an adhesive. In the second step, after the first step, the multi-hole pipe is brazed or welded to the common space forming member while cooling the joint portion between the fin and the multi-hole pipe. In the first step, heating is performed to cure the adhesive. In the second step, the temperature of the brazed part or the welded part of the multi-hole tube and the common space forming member becomes higher than the temperature of the adhesive whose temperature has risen due to the heating for curing the adhesive. The temperature is raised to.

Here, the common space forming member is not particularly limited, and includes a member forming a space in which a plurality of flow paths such as a header, a branch pipe, and a collecting pipe used in a heat exchanger merge. Is done.

The adhesive used in the first step is not particularly limited, and includes an adhesive that is bonded at a temperature lower than the temperature required for brazing or welding in the second step.

Here, in brazing, a melted brazing material is arranged between the multi-hole pipe and the common space forming member, and both are joined. In welding, the joints of the multi-hole pipe and / or the common space forming member are melted to join the two.

The cooling is not particularly limited, and includes various cooling methods such as air cooling that supplies air at a lower temperature to the cooling target location and water cooling that supplies a liquid having a lower temperature to the cooling target location.

In this method of manufacturing a heat exchanger, the fins and the multi-hole pipe are first joined with an adhesive in the first step, and then the multi-hole pipe and the common space forming member are brazed or welded in the second step. For this reason, since the fins and the multi-hole pipe are joined with an adhesive, it is possible to prevent the multi-hole pipe from being deformed by heat by a joining method such as brazing with heating, and the deformation is suppressed. Can be brazed or welded to the common space forming member, and the position of the multi-hole pipe and the connection destination of the common space forming member can be easily performed. Therefore, the work of brazing or welding the multi-hole pipe to the common space forming member can be easily performed.

Further, in the method of manufacturing this heat exchanger, when brazing or welding the multi-hole pipe and the common space-forming member, the heating or temperature rise of the joint portion between the multi-hole pipe and the common space-forming member causes the fin and the multi-hole pipe to rise. The influence on the joint portion with the fin can be sufficiently suppressed by positively cooling the joint portion between the fin and the multi-hole pipe. In particular, the fins and the multi-hole tube in the heat exchanger are originally required to have high heat exchange performance, and are therefore configured to have high heat transfer performance. Therefore, it is possible to obtain the effect that the joint portion between the fin and the multi-hole pipe is sufficiently cooled by a slight cooling treatment. Therefore, it is possible to sufficiently suppress the deterioration of the adhesive for joining the fin and the multi-hole pipe due to the temperature.

Further, in this heat exchanger manufacturing method, the temperature of the brazed part or the welded part between the multi-hole pipe and the common space forming member at the time of brazing or welding is higher than the temperature for curing the adhesive. Therefore, the temperature of the adhesive for joining the fin and the multi-hole pipe tends to rise. However, even in this case, when the multi-hole pipe and the common space forming member are brazed or welded, the heating or temperature rise of the joint portion between the multi-hole pipe and the common space forming member causes the fin and the multi-hole pipe to rise. The influence on the joint portion can be suppressed. Therefore, even when the temperature of the brazed portion or the welded portion between the multi-hole pipe and the common space forming member is high, deterioration due to the temperature of the adhesive for joining the fin and the multi-hole pipe is suppressed. Will be possible.

Method of manufacturing a heat exchanger according to the third aspect is a method of manufacturing a heat exchanger according to the second aspect, in the second step, the temperature of the joint portion between the fin and the multihole tube maintained at 350 ° C. or less Braze or weld while cooling as per.

In this method of manufacturing a heat exchanger, when brazing or welding a multi-hole pipe and a common space forming member, heating or a temperature rise of the joint portion between the multi-hole pipe and the common space forming member causes the fin and the multi-hole pipe to rise in temperature. Since the influence on the joint portion can be sufficiently suppressed by actively cooling the joint portion between the fin and the multi-hole pipe so as to be maintained at 350 ° C. or lower, the fin and the multi-hole pipe are joined. It is possible to further suppress the deterioration of the adhesive due to the temperature.

The method for manufacturing the heat exchanger according to the fourth aspect is the method for manufacturing the heat exchanger according to any one of the first to third aspects, and the fins used in the first step and the second step are on the surface. , A hydrophilic coating is formed.

In this method for manufacturing a heat exchanger, the fins used in the first step and the second step have a hydrophilic coating film formed on the surface in advance. For this reason, there is a problem that the paint is hard to spread as compared with the case where the paint film is formed by impregnating the paint film forming paint together with the multi-hole tube, the fins, and the common space forming member after assembling the heat exchanger. It is possible to avoid. Further, if the fin temperature rises excessively in the first step or the second step, the previously provided hydrophilic coating film may deteriorate, but the multi-hole pipe and the common space forming member Since it is possible to suppress the influence of heating or temperature rise of the joint portion between the multi-hole pipe and the common space forming member on the joint portion between the fin and the multi-hole pipe when brazing or welding the pipe, hydrophilic coating is applied in advance. Even when fins on which a film is formed are used, deterioration of the hydrophilic coating film due to temperature can be suppressed.

The method for manufacturing a heat exchanger according to the fifth aspect is the method for manufacturing a heat exchanger according to any one of the first to fourth aspects, and the fin has an opening into which a multi-hole tube is inserted. ing.

Here, the multi-hole tube is inserted from the direction perpendicular to the thickness direction of the fin with respect to the opening of the fin.

In this heat exchanger manufacturing method, even if the fixing method of integrating the fin and the multi-hole tube by expanding the multi-hole tube cannot be used, the fin opens the opening into which the multi-hole tube is inserted. Have. Therefore, the work of fixing the fins to the multi-hole pipe becomes easy.

The method for manufacturing the heat exchanger according to the sixth aspect is the method for manufacturing the heat exchanger according to any one of the first to fourth aspects, and the fin is a corrugated fin.

In this method of manufacturing a heat exchanger, since corrugated fins are used as fins, even if the distance between the multi-hole pipes changes, the corrugated fins easily absorb the change. This facilitates the manufacture of heat exchangers.

In the method for manufacturing a heat exchanger according to the first aspect, it is possible to simplify the manufacturing work while suppressing the deformation of the multi-hole tube due to heat. Further, it becomes possible to suppress deterioration due to temperature of the adhesive for joining the fin and the multi-hole pipe. Further, even when the temperature of the brazed portion or the welded portion between the multi-hole pipe and the common space forming member is high, deterioration due to the temperature of the adhesive for joining the fin and the multi-hole pipe should be suppressed. Becomes possible.

In the method for manufacturing a heat exchanger according to the second aspect, it is possible to simplify the manufacturing work while suppressing the deformation of the multi-hole tube due to heat. Further, it becomes possible to sufficiently suppress deterioration due to temperature of the adhesive for joining the fin and the multi-hole pipe. Further, even when the temperature of the brazed portion or the welded portion between the multi-hole pipe and the common space forming member is high, deterioration due to the temperature of the adhesive for joining the fin and the multi-hole pipe should be suppressed. Becomes possible.

In the method for manufacturing a heat exchanger according to the third aspect, it is possible to further suppress deterioration due to temperature of the adhesive for joining the fin and the multi-hole pipe.

In the method for manufacturing a heat exchanger according to the fourth aspect, it is possible to suppress deterioration of the hydrophilic coating film due to temperature even when fins having a hydrophilic coating film formed in advance are used.

In the method for manufacturing a heat exchanger according to the fifth aspect, the work of fixing the fins to the multi-hole pipe becomes easy.

The method for manufacturing a heat exchanger according to the sixth aspect facilitates the manufacture of a heat exchanger.

It is a schematic external perspective view of the heat exchanger according to the embodiment. It is a partially enlarged view which shows the structure of a heat transfer fin. It is explanatory drawing of the brazing work of a flat multi-hole pipe and a header. It is a partially enlarged schematic configuration perspective view of the heat exchanger according to another embodiment (A).

Hereinafter, the heat exchanger manufactured by the method for manufacturing the heat exchanger of the present invention and the manufacturing method thereof will be described with reference to the drawings. The following embodiments are specific examples of the present invention, do not limit the technical scope of the present invention, and can be appropriately modified without departing from the gist of the invention.

(1) Structure of heat exchanger A heat exchanger is a heat exchanger used by being housed in an outdoor unit and / or an indoor unit in a known refrigerating device or air conditioner.

Hereinafter, the detailed structure of the heat exchanger 3 of the present embodiment will be described with reference to the drawings.

FIG. 1 is a schematic external perspective view of the heat exchanger 3 according to the present embodiment. FIG. 2 shows an enlarged view of the heat transfer fin 12 seen from the longitudinal direction of the flat multi-hole tube 11 in the installed state.

The heat exchanger 3 according to the present embodiment is a so-called air heat exchanger in which a working refrigerant flows inside and air passes outside. The heat exchanger 3 is a laminated heat exchanger.

The heat exchanger 3 mainly has a first header 13 and a second header 14 arranged so as to face each other, a plurality of flat multi-hole tubes 11, and a plurality of heat transfer fins 12.

(1-1) Flat multi-hole tube 11
The flat multi-hole tube 11 is manufactured by extrusion molding or the like using a metal material such as aluminum or an aluminum alloy.

The flat multi-hole tube 11 has upper and lower flat portions serving as heat transfer surfaces, and a plurality of internal flow paths 11a (see FIG. 2) through which the refrigerant flows.

The flat surface portion is long and wide, and in the installed state, constitutes an upper portion of the internal flow path 11a and has a normal direction above the vertical flow path, and constitutes a lower portion of the internal flow path 11a and is vertically downward. It has a plane in the line direction. One end of each flat multi-hole tube 11 is connected to the first header 13, and the other end is connected to the second header 14.

Each internal flow path 11a extends so as to penetrate from one end side to the other end side in the longitudinal direction of the flat multi-hole pipe 11. The plurality of internal flow paths 11a are arranged at predetermined intervals in the width direction of the flat multi-hole pipe 11 (longitudinal direction in the cross section perpendicular to the longitudinal direction of the flat multi-hole pipe 11).

Between the first header 13 and the second header 14 arranged so that the longitudinal direction is the vertical direction, the plurality of flat multi-hole pipes 11 are arranged with a space in the vertical direction. The space formed between one flat multi-hole pipe 11 and the other flat multi-hole pipe 11 is a ventilation space through which the air flow supplied from the fan passes in the width direction of the flat multi-hole pipe 11. In this way, the flat multi-hole tube 11 is arranged so that the upper surface of the flat surface portion faces the lower surface of the flat surface portion of the flat multi-hole tube 11 arranged one above.

(1-2) Heat transfer fin 12
The heat transfer fin 12 is a fin made of aluminum or an aluminum alloy. The heat transfer fin 12 is a plate-shaped member, and is arranged so that the normal direction of one surface and the back surface thereof is parallel to the direction in which the internal flow path 11a of the flat multi-hole tube 11 extends.

The heat transfer fin 12 is a cut extending in the horizontal direction from the upwind side end in the air flow direction to the front of the leeward end or from the leeward end to the front of the upwind end in the installed state. Notches 12a (openings) are formed at predetermined intervals in the vertical direction. The notch 12a has a shape along the upper and lower flat portions of the flat multi-hole pipe 11, and is in direct contact with the outer peripheral surface of the inserted flat multi-hole pipe 11 or is in contact with the adhesive layer 10. To do.

In the state where the flat multi-hole tube 11 is inserted, the heat transfer fin 12 is more than a portion bulging upward from the windward end of the air flow of the flat multi-hole tube 11 or a leeward end. Further, it is configured so that a bulging portion is formed on the leeward side.

(1-3) First header 13
The first header 13 is a substantially cylindrical member made of aluminum or an aluminum alloy. The first header 13 has an opening in the longitudinal direction for fixing and supporting the vicinity of one end of the plurality of flat multi-hole pipes 11 in the longitudinal direction in a state where the internal space communicates with the internal flow path 11a of the flat multi-hole pipe 11. It is provided so that multiple lines are lined up in.

Although not particularly limited, the outer diameter of the first header 13 is preferably 15 mm or more and 30 mm or less, and may be 20 mm or more and 25 mm or less.

(1-4) Second header 14
Like the first header 13, the second header 14 is a substantially cylindrical member made of aluminum or an aluminum alloy. In the second header 14, the internal space communicates with the internal flow path 11a of the flat multi-hole pipe 11 in the vicinity of the end opposite to the end on the side of the first header 13 in the longitudinal direction of the plurality of flat multi-hole pipes 11. A plurality of openings for fixing and supporting the state are provided so as to be arranged in the longitudinal direction.

The outer diameter of the second header 14 is not particularly limited, but is the same as the outer diameter of the first header 13.

(2) Manufacturing Method of Heat Exchanger Hereinafter, the manufacturing method of the heat exchanger of the present embodiment will be described in detail with reference to an example.

(2-1) Preparation of flat multi-hole tube, heat transfer fins, and header The flat multi-hole tube is made of the above-mentioned aluminum or aluminum alloy, and a clad material for brazing is applied to the outer surface. Prepare what has been done. A hydrophilic coating film may be further provided on the outer surface of the flat multi-hole tube.

The heat transfer fin is made of the above-mentioned aluminum or aluminum alloy and has a notch (opening) for inserting and fitting a flat multi-hole tube, and a hydrophilic coating film is provided on the outer surface. Prepare things. The hydrophilic coating film is not particularly limited, but is a coating material containing, for example, one or a mixture of two or more selected from the group consisting of an epoxy resin, an acrylic resin, and a polyvinyl alcohol resin on the surface of the heat transfer fin. It may be obtained by applying and drying. The film thickness of the hydrophilic coating film is not particularly limited, but can be, for example, 1 μm or more and 10 μm or less.

As the header, a header made of the above-mentioned aluminum or aluminum alloy and having a clad material for brazing coated on the outer surface is prepared.

(2-2) Adhesion Step of Flat Multi-hole Tube and Heat Transfer Fin The flat multi-hole tube and heat transfer fin prepared above are bonded using an adhesive.

Since the flat multi-hole pipe has a flat shape, it cannot be joined by expanding the pipe as in the case of joining a cylindrical pipe and a heat transfer fin. However, here, the flat multi-hole tube is fitted into the notch provided in the heat transfer fin, and the two can be joined by using an adhesive.

Specifically, an adhesive is applied between the outer surface of the flat multi-hole tube and the notch of the heat transfer fin, and the adhesive is applied in a state where the flat multi-hole tube is fitted in the notch of the heat transfer fin. Join by curing.

Here, the adhesive is not particularly limited, and is, for example, one or more selected from the group consisting of an epoxy resin, a urethane resin, an acrylic resin, a polyvinyl alcohol resin, and a nylon resin. It preferably contains a mixture. The adhesive may be a thermosetting resin or an ultraviolet curable resin. The adhesive to be applied preferably contains a metal filler in order to improve the heat transferability between the flat multi-hole tube and the heat transfer fins.

The adhesive may be cured at room temperature, but may be cured by heating to a temperature of 300 ° C. or lower, more preferably 250 ° C. or lower. The lower limit temperature when heating the adhesive is not particularly limited, but can be, for example, 100 ° C. The heating time when the adhesive is cured by heating is not particularly limited, but can be 3 minutes or more and 10 minutes or less with the ambient temperature raised to the above temperature, and 5 minutes or more and 8 minutes or less. Is preferable.

Even when the adhesive is heated, the flat multi-hole tube and the header are used when brazing the flat multi-hole tube and the header in order to prevent the adhesive from being denatured and deteriorated by high temperature. It is preferable to heat so that the temperature is lower than the temperature of the joint portion with.

In addition, in order to suppress the deformation of the flat multi-hole tube due to heat and the deterioration of the hydrophilic coating film of the heat transfer fins due to heat, welding or brazing of the flat multi-hole tube and the heat transfer fins is performed. Not done.

(2-3) Brazing step between the flat multi-hole tube and the header One end of the flat multi-hole tube to which the heat transfer fins are joined is inserted into the opening of the header, and both are brazed by heating the joint. Let me.

Specifically, since the brazing material as a clad material is applied to the outer surface of the flat multi-hole pipe and the outer surface of the header, the brazing material becomes fluid when heated, and the portion concerned. By stopping the heating or cooling the pipe, the flat multi-hole pipe and the header are hardened at the joint, and the flat multi-hole pipe and the header are joined.

The brazing material as the clad material may be applied only to the outer surface of the flat multi-hole pipe, or may be applied only to the outer surface of the header. Further, when the brazing material is not applied to the flat multi-hole pipe or the header, heating may be performed while separately supplying a wire-shaped or paste-shaped brazing material or the like to the joint portion.

Before brazing the flat multi-hole tube and the header, the flat multi-hole tube may be temporarily fixed with an adhesive or the like while being inserted into the opening of the header.

FIG. 3 shows a state of brazing work between the flat multi-hole pipe and the header when viewed from the longitudinal direction of the header.

The brazed portion between the flat multi-hole tube and the header is irradiated with infrared rays from the lamp 30 (halogen lamp). The temperature of the lamp 30 itself rises to about 1200 ° C. Here, the brazed portion between the flat multi-hole tube and the header is preferably heated to 500 ° C. or higher and 800 ° C. or lower, and more preferably 600 ° C. or higher and 700 ° C. or lower.

As shown in FIG. 3, infrared rays from the lamp 30 are inserted between the heat transfer fins 12 closest to the brazed portion between the flat multi-hole tube 11 and the headers 13 and 14 and the headers 13 and 14. It is preferable that a blocking plate 40 for blocking permeation is arranged. By arranging the blocking plate 40 at the time of brazing, it becomes difficult for the infrared rays from the lamp 30 to be supplied to the adhesive joining the heat transfer fin and the flat multi-hole tube, so that the temperature of the adhesive rises. It is possible to suppress the deterioration of the adhesive due to heat. Further, by arranging the blocking plate 40, it is possible to suppress the temperature rise of the hydrophilic coating film on the surface of the heat transfer fins and to suppress the deterioration of the hydrophilic coating film due to heat to a small extent. Here, when the temperature of the brazed portion between the flat multi-hole tube and the header is raised to about 600 ° C., if the blocking plate 40 is not used (when cooling is not performed), the adhesive or the hydrophilic coating film is used. Although the temperature rises to 500 ° C. or higher, the use of the blocking plate 40 makes it possible to keep the temperature of the adhesive or the hydrophilic coating film as low as about 300 ° C. The blocking plate 40 is not particularly limited, but for example, a known metal member capable of blocking infrared rays may be used.

Further, as shown in FIG. 3, when the flat multi-hole tube 11 and the headers 13 and 14 are brazed, the fan 50 is used to target the location where the heat transfer fins 12 of the heat exchanger 3 are arranged. It is preferable to supply the formed air flow to cool the heat transfer fins 12 and the flat multi-hole tube 11. Here, the air volume by the fan 50 is not particularly limited, but for example, when brazing the flat multi-hole tube 11 and the headers 13 and 14, the adhesive that joins the heat transfer fin 12 and the flat multi-hole tube 11 is used. The air volume is preferably maintained at a temperature of 350 ° C. or lower, more preferably the air volume is maintained at a temperature of 300 ° C. or lower, and further preferably the air volume is maintained at a temperature of 250 ° C. or lower. Here, since the heat transfer fins and the flat multi-hole tube have high heat transfer performance required for a heat exchanger, it is possible to obtain a sufficient cooling effect even if only air at room temperature is supplied. it can. Specifically, even when the temperature of the brazed portion between the flat multi-hole tube and the header is raised to about 600 ° C., the temperature of the adhesive or the hydrophilic coating film can be raised to 250 ° C. by using the blocking plate 40 in combination. It can be kept low to a certain extent.

As described above, in order to avoid deterioration of the adhesive that joins the heat transfer fin and the flat multi-hole tube and the hydrophilic coating film of the heat transfer fin due to heat, the heat transfer fin and the flat multi-hole tube are used. Even if the header is integrated, the integrated product is not put into the furnace and brazed.

(3) Manufacturing method of heat exchanger and features of the heat exchanger In the conventional manufacturing method of the heat exchanger, the heat transfer fin and the flat multi-hole tube are welded before fixing the flat multi-hole tube to the header. Since it is fixed, both the flat multi-hole tube and the heat transfer fin have risen to a very high temperature, so the flat multi-hole tube itself may be deformed by heat, and the heat transfer fin is hydrophilic. If a coating film is provided, the hydrophilic function of the film may be impaired.

On the other hand, in the method for manufacturing a heat exchanger according to the present embodiment, the heat transfer fins and the flat multi-hole tube are first joined with an adhesive, and then the flat multi-hole tube and the header are brazed. There is. Therefore, when the heat transfer fin and the flat multi-hole tube are joined, the temperature rise of both the heat transfer fin and the flat multi-hole tube is suppressed, and the flat multi-hole tube can be prevented from being deformed by high heat. For this reason, since the joint work with the header can be performed using a flat multi-hole pipe that is not deformed, it is easy to align the header with respect to the opening position, and it is possible to easily perform the brazing work. Become. Further, with respect to the heat transfer fins, since the temperature rise is suppressed, functional deterioration of the hydrophilic coating film can be avoided.

Further, although high heat is generated when brazing the flat multi-hole tube and the header, the heat transfer fin and the flat multi-hole tube are joined by continuing to supply cooling air while using the blocking plate 40 that blocks infrared rays. The degree to which the temperature of the hydrophilic coating film on the surface of the adhesive or heat transfer fin is increased can be suppressed to a small extent, and the deterioration of these can be suppressed. Therefore, it is possible to maintain a good joint state between the heat transfer fin and the flat multi-hole tube, and it is possible to fully exert the hydrophilic function of the hydrophilic coating film of the heat transfer fin.

(4) Modification Example The above embodiment can be appropriately modified as shown in the following modification examples. In addition, each modification may be applied in combination with another modification as long as there is no contradiction.

(4-1) Modification A
In the above embodiment, a heat exchanger is manufactured by using a plug-in type heat transfer fin provided with an opening for fitting a flat multi-hole tube at an end portion in a direction perpendicular to the thickness direction of the heat transfer fin. Was explained as an example.

On the other hand, the heat transfer fins used in the method for manufacturing the heat exchanger are not limited to the plug-in type heat transfer fins, and may be, for example, corrugated fins. FIG. 4 shows a partially enlarged schematic configuration perspective view of a heat exchanger in which the corrugated fin 212 is used. When the corrugated fin 212 is used as the heat transfer fin, the flat multi-hole tube is brazed or welded as compared with the plug-in type fin of the above embodiment in which the notch for fitting the flat multi-hole tube is provided. Since the corrugated fin 212 is easily deformed even if it is sometimes deformed, it is possible to easily absorb the change in the shape of the flat multi-hole tube.

(4-2) Modification B
In the above embodiment, a header has been described as an example as a member forming a common space in which a plurality of flat multi-hole pipes are joined.

On the other hand, the member forming the common space is not limited to the header, and a branch pipe, a collecting pipe, or the like to which three or more pipes are joined may be used instead of the header.

(4-3) Modification C
In the above embodiment, a case where the flat multi-hole tube and the header are fixed by brazing by infrared irradiation using a halogen lamp has been described as an example.

On the other hand, the brazing method between the flat multi-hole tube and the header is not limited to brazing by infrared irradiation using a halogen lamp, but brazing is performed by high-frequency heating in which an induction coil is arranged around the heating target portion. You may do so. In this case, in order to make it difficult for the high frequency to reach the heat transfer fin or the flat multi-hole tube side, a metal plate member or the like for blocking the high frequency can be used instead of the blocking plate.

(4-4) Modification D
In the above embodiment, a case where the flat multi-hole tube and the header are fixed by brazing has been described as an example.

On the other hand, the method of fixing the flat multi-hole pipe and the header is not limited to brazing, and may be fixed by welding. The welding is not particularly limited, and examples thereof include laser welding and resistance welding. In particular, when laser welding is used, local heating is possible, so even if the above blocking plate is not used or cooling treatment is not used, the temperature of the adhesive or hydrophilic coating film is about 300 ° C. It is possible to keep it low.

(4-5) Modification E
In the above embodiment, a case where the joint portion between the flat multi-hole pipe and the heat transfer fin is cooled by air cooling when brazing the flat multi-hole pipe and the header has been described as an example.

On the other hand, when brazing or welding the flat multi-hole tube and the header, water cooling may be performed instead of air cooling to supply a liquid such as water having a temperature lower than that of the cooling target portion.

The present invention can be used in refrigeration equipment.

3: Heat exchanger 11: Flat multi-hole tube (multi-hole tube)
11a: Internal space 12: Heat transfer fins (fins)
12a: Notch (opening)
13: First header (common space forming member)
14: Second header (common space forming member)
30: Heater 40: Blocking plate 50: Fan 212: Corrugated fin

Japanese Unexamined Patent Publication No. 2013-92265

Claims (6)

A common space forming member (13) made of aluminum or an aluminum alloy to which a fin (12) made of aluminum or an aluminum alloy, a plurality of multi-hole pipes (11) made of aluminum or an aluminum alloy, and the plurality of the multi-hole pipes are connected. , 14), which is a method for manufacturing a heat exchanger (3).
The first step of joining the fin and the multi-hole tube with an adhesive, and
After the first step, a second step of brazing or welding the multi-hole pipe to the common space forming member while performing a process of suppressing a temperature rise of the joint portion between the fin and the multi-hole pipe .
Equipped with a,
In the first step, heating is performed to cure the adhesive.
In the second step, the temperature of the brazed portion or the welded portion of the multi-hole tube and the common space forming member is higher than the temperature of the adhesive whose temperature has risen by heating for curing the adhesive. To raise the temperature to a higher temperature,
How to manufacture a heat exchanger. A common space forming member (13) made of aluminum or an aluminum alloy to which a fin (12) made of aluminum or an aluminum alloy, a plurality of multi-hole pipes (11) made of aluminum or an aluminum alloy, and the plurality of the multi-hole pipes are connected. , 14), which is a method for manufacturing a heat exchanger (3).
The first step of joining the fin and the multi-hole tube with an adhesive, and
After the first step, a second step of brazing or welding the multi-hole pipe to the common space forming member while cooling the joint portion between the fin and the multi-hole pipe.
With
In the first step, heating is performed to cure the adhesive.
In the second step, the temperature of the brazed portion or the welded portion of the multi-hole tube and the common space forming member is higher than the temperature of the adhesive whose temperature has risen by heating for curing the adhesive. To raise the temperature to a higher temperature,
How to manufacture a heat exchanger. In the second step, the brazing or welding is performed while cooling so that the temperature of the joint portion between the fin and the multi-hole pipe is maintained at 350 ° C. or lower.
The method for manufacturing a heat exchanger according to claim 2. The fins used in the first step and the second step have a hydrophilic coating film formed on the surface thereof.
The method for manufacturing a heat exchanger according to any one of claims 1 to 3 . The fin has an opening into which the multi-hole tube is inserted.
The method for manufacturing a heat exchanger according to any one of claims 1 to 4 . The fin is a corrugated fin,
The method for manufacturing a heat exchanger according to any one of claims 1 to 4 .

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