JP2020094758A - Header, heat transfer pipe, and heat exchanger - Google Patents

Abstract

To provide a header, a heat transfer pipe, and a heat exchanger that can be brazed with sufficient strength.SOLUTION: A header 10R comprises an outer part, a flow passage formed inside the outer part, an insertion hole 11 penetrating to the flow passage from the outer part, and grooves 12 formed in inner walls 111 and 112 of the insertion hole 11. Fluid is passed through the flow passage. A heat transfer pipe 20 is inserted into the insertion hole 11, and thereby the fluid is passed between the heat transfer pipe 20 and the flow passage. The grooves 12 extend in the penetrating direction of the insertion hole 11.SELECTED DRAWING: Figure 4

Description

The present invention relates to a header, a heat transfer tube and a heat exchanger.

Some heat exchangers include a heat transfer tube through which a fluid to be heat-exchanged flows, and a header that distributes the fluid to the heat transfer tube, and the heat transfer tube and the header are joined by a brazing material.

For example, Patent Document 1 includes a header having an insertion hole formed in the outer shell and a heat transfer tube having an end inserted in the insertion hole, and a heat transfer tube in which the heat transfer tube is joined to the header. A switch is disclosed.

In the heat exchanger described in Patent Document 1, the header is formed with a cylinder surrounding the opening of the insertion hole. The inner diameter of the cylinder is larger than the inner diameter of the insertion hole, and the inner diameter of the insertion hole is the same as the outer diameter of the heat transfer tube. In the heat exchanger described in Patent Document 1, the heat transfer tube is inserted into the insertion hole. The brazing material is filled in the gap between the heat transfer tube and the cylinder. Thereby, the heat transfer tube and the header are joined.

JP, 2008-260049, A

In the heat exchanger described in Patent Document 1, the inner diameter of the header cylinder is larger than the inner diameter of the insertion hole, and the inner diameter of the insertion hole is the same as the outer diameter of the heat transfer tube. Therefore, the brazing material is used as the insertion hole and the heat transfer tube. Hardly filled between. As a result, the heat transfer tube is joined only by the cylinder, and the heat transfer tube and the header may not be joined with sufficient strength.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a header, a heat transfer tube, and a heat exchanger that can be brazed with sufficient strength.

In order to achieve the above-mentioned object, a header according to the present invention is formed with an outer shell portion, a flow path through which a fluid flows, and a heat transfer tube inserted from the outer shell portion to the flow path. Accordingly, the insertion hole that allows the fluid to flow between the heat transfer tube and the flow path, and the uneven portion formed on the inner wall of the insertion hole are provided. The uneven portion extends in the penetrating direction of the insertion hole.

According to the configuration of the present invention, the uneven portion is formed on the inner wall of the insertion hole and extends in the penetrating direction of the insertion hole. Therefore, even when a sufficient gap is not formed between the heat transfer tube and the inner wall of the insertion hole when the heat transfer tube is inserted into the insertion hole, a space extending in the penetration direction of the insertion hole between the heat transfer tube and the insertion hole. Can be secured. As a result, the brazing material sufficiently penetrates into the header, and the header and the heat transfer tube can be brazed with sufficient strength.

The perspective view of the heat exchanger which concerns on Embodiment 1 of this invention. The perspective view of the header with which the heat exchanger which concerns on Embodiment 1 of this invention is equipped. 1 is a perspective view of a heat transfer tube included in a heat exchanger according to Embodiment 1 of the present invention. An enlarged plan view of the IV area shown in FIG. Sectional view of the V-V section line shown in FIG. Sectional drawing of a header at the time of manufacture of the heat exchanger which concerns on Embodiment 1 of this invention, a heat transfer tube is inserted in an insertion hole, and a brazing material is arrange|positioned. Sectional drawing of a header at the time of manufacture of the heat exchanger which concerns on Embodiment 1 of this invention, when a brazing material permeates an insertion hole and a groove. The enlarged plan view of the insertion hole of the header with which the heat exchanger which concerns on Embodiment 2 of this invention is equipped. Sectional view of section line IX-IX shown in FIG. Enlarged plan view of the insertion hole of the header provided in the heat exchanger according to Embodiment 3 of the present invention Sectional view of section line XI-XI shown in FIG. The enlarged plan view of the modification of the insertion hole which the header with which the heat exchanger which concerns on Embodiment 1 of this invention has is provided. An enlarged plan view of an insertion hole of a header in which a modification of the heat transfer tube of the heat exchanger according to Embodiment 3 of the present invention is inserted.

Hereinafter, a header, a heat transfer tube, and a heat exchanger according to an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent parts are designated by the same reference numerals. In the Cartesian coordinate system XYZ shown in the figure, when the tube axis of the heat transfer tube provided in the heat exchanger is oriented in the left-right direction, the tube axis direction is the X-axis, the vertical direction is the Z-axis, and the X-axis and the Z-axis are the same. The direction orthogonal to each other is the Y axis. Hereinafter, this coordinate system will be appropriately referred to for description.

(Embodiment 1)
The heat exchanger according to the first embodiment is a heat exchanger in which the ends of the heat transfer tubes are brazed to the header. In this heat exchanger, the end portion of the heat transfer tube is inserted into the insertion hole of the header, and the heat transfer tube and the header are brazed in the insertion hole. Further, in the insertion hole, a groove for penetrating the brazing material is formed in order to enhance brazing strength. First, the configuration of the heat exchanger will be described with reference to FIGS. 1 to 3. Next, the groove formed in the insertion hole of the header will be described with reference to FIGS. 4 and 5. Subsequently, a brazing method using the groove will be described with reference to FIGS. 6 and 7.

FIG. 1 is a perspective view of a heat exchanger 1A according to Embodiment 1 of the present invention. FIG. 2 is a perspective view of the headers 10R and 10L included in the heat exchanger 1A. FIG. 3 is a perspective view of the heat transfer tube 20 included in the heat exchanger 1A. Note that, in FIG. 1, for easy understanding, only some of the fins 30 included in the heat exchanger 1A are illustrated. Further, the brazing material for joining the heat transfer tube 20 and the headers 10R and 10L is omitted. In FIG. 2, the shapes of the flow paths in the headers 10R and 10L are simplified into a rectangular parallelepiped shape. Further, the groove of the insertion hole 11 is omitted.

As shown in FIG. 1, the heat exchanger 1A includes headers 10R and 10L arranged apart from each other on the left and right sides, a plurality of heat transfer tubes 20 extending in the left and right direction to connect the headers 10R and 10L, and a plurality of heat transfer tubes 20. And a plurality of fins 30 attached to the heat transfer tube 20.

The headers 10R and 10L are members that receive supply of a refrigerant, which is a fluid to be heat-exchanged, from an external device or members that discharge the refrigerant. As shown in FIG. 2, each of the headers 10R and 10L is formed in a rectangular parallelepiped shape and has a hollow inside. The headers 10R and 10L are arranged in parallel with each other with the longitudinal direction facing the depth direction. The left side surface of the header 10L is provided with a refrigerant inlet/outlet 100 penetrating the left side surface for supplying the refrigerant from the external device or discharging the refrigerant to the external device.

On the other hand, a plurality of insertion holes 11 are formed in the left side surface portion of the header 10R and the right side surface portion of the header 10L, that is, the side surface portions of the headers 10R and 10L which face each other, for connecting the plurality of heat transfer tubes 20. In addition, since the side surface portion in which the insertion hole 11 is formed is a portion that defines the outer shapes of the headers 10R and 10L and surrounds the internal space, it is also referred to as an outer shell portion in the present specification.

Each of the insertion holes 11 is formed in a flat shape because each heat transfer tube 20 has a flat tube cross section as described later. Here, the flat shape means an open shape, and in the present specification, it means an elongated rectangular shape in which both ends in the longitudinal direction are rounded in a semicircular shape. Each of the insertion holes 11 has its longitudinal direction oriented vertically. Moreover, it penetrates the side surface portions of the headers 10R and 10L and extends to the internal spaces of the headers 10R and 10L.

An end of the heat transfer tube 20 is inserted into each of the insertion holes 11. Specifically, the right end portion of the heat transfer tube 20 is inserted into the insertion hole 11 of the header 10R, and the left end portion of the heat transfer tube 20 is inserted into the insertion hole 11 of the header 10L. As a result, the headers 10R and 10L are connected by the plurality of heat transfer tubes 20. When the refrigerant is supplied from the external device, the refrigerant flows between the headers 10R and 10L.

As shown in FIG. 3, the heat transfer tube 20 is formed in the flat shape described above in a tube cross-sectional view. This is for facilitating heat conduction from the refrigerant flowing through the heat transfer tube 20. The heat transfer tube 20 linearly extends in the left-right direction while maintaining the linear tube cross-sectional shape.

The inside of the heat transfer tube 20 is partitioned by a plurality of partition walls 21 so that heat from the refrigerant can be more easily conducted. Each of the partition walls 21 is formed of a horizontal plate, and the plurality of partition walls 21 are vertically arranged at regular intervals. Thereby, in the heat transfer tube 20, the heat of the refrigerant is transferred to each of the partition walls 21. As a result, in the heat transfer tube 20, the heat transfer path is increased and the heat of the refrigerant is easily transferred.

Returning to FIG. 1, the heat transfer tube 20 is provided with a plurality of fins 30 for exchanging heat conducted from the refrigerant with air.

Each of the fins 30 is formed in a strip shape in order to increase the surface area and promote heat exchange with air. Moreover, it is formed in a plate shape. Their thickness is 0.09-2.0 mm. Further, each of the fins 30 receives heat from the heat transfer tube 20, so that a notch 31 is formed on the upper end side, and the heat transfer tube 20 is fitted into the notch 31. The fins 30 and the fins 30 are superposed in the left-right direction at intervals of 1.0 to 2.0 mm so that air flows between them.

The fins 30 and the heat transfer tubes 20 are formed of aluminum or aluminum alloy having high thermal conductivity in order to enhance thermal conductivity. The surface of the fin 30 is surface-treated in order to prevent corrosion, stain resistance, hydrophobicity or hydrophilicity. A sacrificial anode layer made of zinc is provided on the surface of the heat transfer tube 20 for corrosion protection. The headers 10R and 10L are also made of the same material as the fin 30 and the heat transfer tube 20. This reduces the strain when assembled.

As described above, the heat transfer tube 20 is connected to the headers 10R and 10L by being inserted into the insertion holes 11 of the headers 10R and 10L. In order to firmly fix the heat transfer tube 20 and the headers 10R and 10L to improve airtightness and watertightness, in the assembly of the heat exchanger 1A, after inserting the heat transfer tube 20 into the insertion hole 11, the insertion hole 11 and the heat transfer tube 20 are inserted. The melted brazing material is infiltrated into the gap between and. As a result, the gap between the insertion hole 11 and the heat transfer tube 20 is filled with the brazing material to enhance the joint strength.

However, if the heat transfer tubes 20 are arranged in a biased manner in the insertion hole 11, there may occur a portion having a large gap and a portion having a small gap in the insertion hole 11. In that case, the brazing material is not filled in a part of the portion, which causes so-called wax breakage.

Further, in the assembly of the heat exchanger 1A, the melted brazing material may be supplied from the opening of the insertion hole 11 opened outside the headers 10R and 10L. In this case, if there is a small portion in the above-mentioned gap, the melted brazing material may not sufficiently penetrate, and a sufficient amount of the brazing material may not be supplied to the inside of the headers 10R, 10L. In that case, the row fillet may not be formed inside the headers 10R and 10L.

Therefore, in order to prevent wax breakage or ensure formation of a row fillet and increase the bonding strength, a groove extending in the same direction as the penetrating direction of the insertion hole 11 is formed on the inner wall of the insertion hole 11. Next, the configuration of the insertion hole 11 and its groove will be described with reference to FIGS. 4 and 5.

FIG. 4 is an enlarged plan view of the IV area shown in FIG. FIG. 5 is a cross-sectional view taken along the line VV shown in FIG. 4 and 5, the space inside the heat transfer tube 20 and the partition wall 21 are omitted for easy understanding. Further, the gap between the insertion hole 11 and the heat transfer tube 20, the size of the groove 12, and the size of the brazing material 40 are emphasized. The same applies to FIGS. 6 to 13 described later.

As described above, the insertion hole 11 is formed in a flat shape with the longitudinal direction oriented vertically. As a result, as shown in FIG. 4, the insertion hole 11 and the planar inner walls 111 and 112 that are opposed to each other in the lateral direction and are parallel to the XZ plane and the longitudinally opposed inner walls 113 and 114 that are semi-cylindrical. Have. Of these inner walls 111-114, a plurality of grooves 12 are formed in the inner walls 111, 112, respectively.

Each of the grooves 12 is recessed in a semi-cylindrical shape from the inner walls 111 and 112 to the outside of the insertion hole 11. The depth of the groove 12 is such that, when the brazing material 40 is melted and supplied to the end portion of the groove 12, the melted brazing material 40 penetrates. In general, the penetration of the brazing material 40 depends on the surface energy of the header 10R and the heat transfer tube 20 to be brazed, the surface energy of the melted brazing material 40, and the interfacial energy between the header 10R and the heat transfer tube 20 and the melting brazing material 40. It depends on the wettability determined by the balance. Therefore, although depending on the surface treatment of the header 10R and the heat transfer tube 20, for example, the brazing material 40 is an aluminum braze in which silicon is added to aluminum, and the thickness of the header 10R is 6 mm or more. When the overlapping margin is 6 mm or more, the depth of the groove 12 is 0.20 to 0.25 mm.

Further, as shown in FIG. 5, each groove 12 linearly extends in the X direction, which is the penetrating direction of the insertion hole 11. Thereby, each groove 12 forms a space connecting the outer side and the inner side of the header 10R between the heat transfer tube 20 and the inner walls 111, 112.

On the other hand, the brazing material 40 is filled inside the groove 12. The brazing material 40 is filled not only inside the groove 12 but also in the gap between the heat transfer tube 20 and the inner wall 111-114. The brazing material 40 further protrudes from the −X side opening and the +X side opening of the insertion hole 11 to the periphery of these openings to form a brazing fillet. As a result, the brazing material 40 joins the heat transfer tube 20 and the header 10R.

Although not shown, the other insertion hole 11 of the header 10R is also provided with a groove 12 having a similar structure. Further, the insertion hole 11 formed in the header 10L is also provided with a groove 12 having a similar structure. By filling the groove 12 with the brazing material 40, the heat transfer tube 20 and the headers 10R and 10L are firmly joined. As a result, the airtightness and watertightness of the heat exchanger 1A are improved. Next, a brazing method using the groove 12 will be described with reference to FIGS. 6 and 7.

FIG. 6 is a cross-sectional view of the header 10R when the heat exchanger 1A according to Embodiment 1 of the present invention is manufactured and the heat transfer tube 20 is inserted into the insertion hole 11 and the brazing material 40 is arranged. FIG. 7 is a cross-sectional view of the header 10R when the brazing material 40 has penetrated into the insertion hole 11 and the groove 12. 6 and 7, the shape of the flow path in the header 10R is simplified to a rectangular shape in the XZ sectional view for easy understanding.

First, the fin 30 is formed into the shape described above by pressing. Further, the heat transfer tube 20 is formed into the above-described shape by a processing method such as extrusion molding, drawing molding, and bending. Similarly, the headers 10R and 10L are formed in the shape described above.

Next, the formed fins 30 are attached to the heat transfer tubes 20 in the above-described arrangement. Subsequently, the fins 30 and the heat transfer tubes 20 are brazed. This brazing is performed by applying a paste-like brazing material 40 to the heat transfer tube 20 in advance, attaching the fins 30 and then heating. As a result, a heat exchanger core including the fins 30 and the heat transfer tubes 20 is manufactured.

Next, the above heat exchanger core is attached to the produced headers 10R and 10L. Specifically, as shown in FIG. 6, the +X end of the heat transfer tube 20 of the heat exchanger core is inserted into the insertion hole 11 of the header 10R arranged in the above-described direction. Although not shown, the -X end of the heat transfer tube 20 is inserted into the insertion hole 11 of the header 10L. As a result, the heat exchanger 1A is assembled into the shape shown in FIG.

Next, as shown in FIG. 6, a paste-like or wire-like brazing material 40 is arranged around the opening of the insertion hole 11 formed in the header 10R so as to surround the opening. Although not shown, the brazing material 40 is similarly arranged on the header 10L. Subsequently, the headers 10R and 10L on which the brazing material 40 is arranged and the heat exchanger core are heated. As a result, the brazing material 40 is melted and penetrates into the insertion hole 11.

At this time, the brazing material 40 penetrates into the gap between the heat transfer tube 20 and the inner wall 111-114 of the insertion hole 11. The brazing material 40 also penetrates into the groove 12. As a result, the brazing material 40 reaches the inside of the headers 10R and 10L. As a result, the brazing material 40 fills the gap between the heat transfer tube 20 and the inner wall 111-114 and the inside of the groove 12. As a result, these gaps and the groove 12 are closed.

In addition, when the tube axis of the heat transfer tube 20 is not arranged on the central axis of the insertion hole 11 and the heat transfer tube 20 is arranged deviated in the Y direction, a gap between the heat transfer tube 20 and one of the inner walls 111-114 of the insertion hole 11 is formed. However, since the groove 12 is formed in the inner walls 111 and 112 of the insertion hole 11, the brazing material 40 reaches at least the inside of the headers 10R and 10L through the groove 12. As a result, even in this case, the gap between the heat transfer tube 20 and the inner wall 111-114 and the groove 12 are closed.

Since the brazing material 40 reaches the inside of the headers 10R and 10L, the brazing material 40 forms a row fillet between the inner wall surfaces of the headers 10R and 10L and the heat transfer tube 20 inside the headers 10R and 10L. On the other hand, on the outside of the headers 10R and 10L, the brazing material 40 forms a row fillet between the outer wall surface of the headers 10R and 10L and the heat transfer tube 20. As a result, the gap between the insertion hole 11 and the heat transfer tube 20 is sealed.

Then, the heating of the headers 10R and 10L and the heat exchanger core is terminated. Then, the headers 10R and 10L and the heat exchanger core are cooled. This completes the brazing of the headers 10R, 10L and the heat exchanger core. Through the above steps, the heat exchanger 1A is completed.

In the completed heat exchanger 1A, the gap between the insertion hole 11 and the heat transfer tube 20 is sealed by the row fillet. For this reason, it is possible to obtain the heat exchanger 1A having high pressure resistance, which is unlikely to cause water penetration and crevice corrosion.

In the above brazing, a paste-shaped or wire-shaped brazing material 40 is arranged at the peripheral edge of the heat transfer tube 20 and the opening of the insertion hole 11. However, by forming the fins 30 and the headers 10R and 10L with the clad material in which the base material of aluminum or aluminum alloy is covered with the brazing material layer, the arrangement of the above-mentioned paste-like or wire-like brazing material 40 is omitted. Good.

As described above, in the heat exchanger 1A according to Embodiment 1 of the present invention, the headers 10R and 10L are formed in the inner walls 111 and 112 of the insertion hole 11 and extend in the penetrating direction of the insertion hole 11. It has twelve. Therefore, when the heat transfer tube 20 is inserted into the insertion hole 11, even if a sufficient gap is not formed between the heat transfer tube 20 and the inner wall of the insertion hole 11, a space where the brazing material 40 penetrates into the insertion hole 11 Can be secured. As a result, in the heat exchanger 1A, the brazing material 40 can sufficiently penetrate into the inside of the headers 10R and 10L, and the headers 10R and 10L and the heat transfer tube 20 can be brazed with sufficient strength.

Even if the tube axis of the heat transfer tube 20 is displaced from the hole center axis of the insertion hole 11, the groove 12 serves as a supply path for the brazing material 40. Therefore, the brazing material 40 can sufficiently penetrate into the headers 10R and 10L. As a result, it is not necessary to arrange the heat transfer tube 20 in the insertion hole 11 with high accuracy, and brazing is easy. Moreover, the insertion hole 11 can be sealed more reliably.

(Embodiment 2)
In the heat exchanger 1A according to Embodiment 1, the groove 12 is formed in the inner walls 111 and 112 of the insertion hole 11. However, the present invention is not limited to this. In the present invention, in order to secure the permeation path of the brazing material 40, it is preferable that the inner wall 111-114 of the insertion hole 11 is provided with an uneven portion extending in the penetrating direction of the insertion hole 11. In the heat exchanger 1B according to the second embodiment, the protrusion is provided in the insertion hole 11 as this uneven portion. Hereinafter, the heat exchanger 1B according to Embodiment 2 will be described with reference to FIGS. 8 and 9. In the second embodiment, a configuration different from that of the first embodiment will be described.

FIG. 8 is an enlarged plan view of the insertion hole 11 of the header 10R included in the heat exchanger 1B according to Embodiment 2 of the present invention. FIG. 9 is a cross-sectional view taken along the line IX-IX shown in FIG.

As shown in FIG. 8, in the heat exchanger 1B, the header 10R includes a plurality of protrusions 13 formed on the inner walls 111 and 112 of the insertion hole 11.

Each of the protrusions 13 projects from the inner walls 111 and 112 to the inside of the insertion hole 11. Specifically, the protrusion 13 on the inner wall 111 projects in the −Y direction. Further, the projection 13 on the inner wall 112 projects in the +Y direction. The protrusion amount thereof is the same as the depth of the groove 12 described in the first embodiment. That is, when the brazing material 40 is melted and supplied to the insertion hole 11, the brazing material 40 penetrates into the space between the tip of the projection 13 and the inner walls 111 and 112.

Further, each of the protrusions 13 linearly extends in the X direction, which is the penetrating direction of the insertion hole 11, as shown in FIG. 9. As a result, when the heat transfer tube 20 is inserted into the insertion hole 11, a gap penetrating to the inside of the header 10R is provided between the heat transfer tube 20 and the inner walls 111 and 112 of the insertion hole 11 so that the brazing material 40 can penetrate through the passage. Has been secured.

The gap between the heat transfer tube 20 and the inner walls 111, 112 of the insertion hole 11 formed by the protrusion 13 is filled with a brazing material 40 as shown in FIG. Further, as shown in FIG. 9, the brazing material 40 has a braze fillet formed from the −X side opening and the +X side opening of the insertion hole 11 to the periphery of these openings, as in the first embodiment. Thus, the brazing material 40 joins the heat transfer tube 20 and the header 10R.

Although not shown, the protrusions 13 are formed in all the insertion holes 11 of the header 10R. Further, the projections 13 having the same structure are formed in all the insertion holes 11 of the header 10L. These protrusions 13 also form a gap between the heat transfer tube 20 and the inner walls 111 and 112 of the insertion hole 11. The brazing material 40 is also filled in these gaps to form a braze fillet. The brazing material 40 joins the heat transfer tube 20 to the headers 10R and 10L.

Also in the second embodiment, the brazing filler metal 40 forms the braze fillet to seal the gap between the heat transfer tube 20 and the insertion hole 11 to prevent water from entering and crevice corrosion. Moreover, the pressure resistance of the heat exchanger 1B is improved.

The brazing method of the heat exchanger 1B according to Embodiment 2 is different from the brazing material 40 except that the brazing material 40 penetrates into the gap between the heat transfer tube 20 and the insertion hole 11 formed by the protrusion 13. It is similar to the first embodiment. Therefore, the description of the brazing method of the heat exchanger 1B according to the second embodiment is omitted.

As described above, in the heat exchanger 1B according to Embodiment 2 of the present invention, the headers 10R and 10L are formed on the inner walls 111 and 112 of the insertion hole 11 and extend in the penetrating direction of the insertion hole 11. Equipped with 13. Therefore, as in the first embodiment, a space is ensured between the heat transfer tube 20 inserted into the insertion hole 11 and the inner walls 111 and 112 of the insertion hole 11 so that the brazing material 40 penetrates into the insertion hole 11. can do. As a result, in the heat exchanger 1B, the brazing material 40 can sufficiently penetrate into the inside of the headers 10R and 10L, and the headers 10R and 10L and the heat transfer tube 20 can be brazed with sufficient strength.

(Embodiment 3)
In the heat exchangers 1A and 1B according to the first and second embodiments, the groove 12 or the protrusion 13 is formed in the insertion hole 11. However, the present invention is not limited to this. In the present invention, the groove 12 or the protrusion 13 may be formed as the above-mentioned uneven portion on the heat transfer tube 20 side instead of the insertion hole 11 side. In the heat exchanger 1C according to Embodiment 3, a projection is formed at the end of the heat transfer tube 20. Hereinafter, the heat exchanger 1C according to the third embodiment will be described with reference to FIGS. 10 and 11. In the third embodiment, a configuration different from the first and second embodiments will be described.

FIG. 10 is an enlarged plan view of the insertion hole 11 of the header 10R included in the heat exchanger 1C according to Embodiment 3 of the present invention. 11 is a cross-sectional view taken along the line XI-XI shown in FIG.

As shown in FIG. 10, the heat exchanger 1C is provided with a plurality of protrusions 53 protruding from the outer periphery of the heat transfer tube 50 to the outside thereof.

Specifically, the heat transfer tube 50 has its tube axis oriented in the X direction, as in the first embodiment. The heat transfer tube 50 has a flat shape in a cross section parallel to the YZ plane. The heat transfer tube 50 is arranged on the +Y and -Y sides, and has two plane outer walls parallel to the XZ plane and two semi-cylindrical part outer walls arranged on the +Z and -Z sides and continuous with the plane outer walls. .. The projections 53 are provided on the plane outer walls, and project further outward from the plane outer walls. In addition, each of the protrusions 53 is arranged so as to be separated in the Z direction.

The protrusion 53 is formed in a semicircular shape in the YZ cross section. The radius, in other words, the protrusion amount of the protrusion 53 is the same as the protrusion amount of the protrusion 13 described in the second embodiment. As shown in FIG. 11, the protrusion 53 extends to the end of the heat transfer tube 50 from a position separated from the end of the heat transfer tube 50 by a distance L while maintaining the YZ sectional shape. The distance L is larger than the thickness T of the outer portion of the header 10R. As a result, the protrusion 53 extends further to the +X side than the +X side opening through the −X side opening of the insertion hole 11 in a state where the end side of the heat transfer tube 50 is inserted into the insertion hole 11 of the header 10R. ing.
In addition, in this specification, a portion from the end of the heat transfer tube 50 to the distance L is also referred to as an insertion portion of the heat transfer tube 50.

Returning to FIG. 10, in the header 10R, unlike the first and second embodiments, the groove 12 or the protrusion 13 is not formed in the insertion hole 11, and the inner walls 111 and 112 are flat. The tips of the protrusions 53 are in contact with the inner walls 111 and 112. The brazing material 40 is filled between the projections 53 and between the inner walls 111 and 112 and the heat transfer tube 50. Then, as shown in FIG. 11, the brazing material 40 protrudes from the −X side opening and the +X side opening of the insertion hole 11 to the periphery of these openings to form a row fillet.

Although not shown, the heat transfer tube 50 inserted into the other insertion hole 11 of the header 10R is also provided with a projection 53 having a similar configuration. Further, the heat transfer tube 50 inserted into the insertion hole 11 of the header 10L is also provided with a projection 53 having a similar configuration. The brazing material 40 is also filled between the insertion holes 11 and the heat transfer tubes 50. Then, the brazing material 40 extends to the peripheral edge of the insertion hole 11 to form a brazing fillet.

Also in the third embodiment, as in the first and second embodiments, the brazing material 40 forms a braze fillet to seal the gap between the heat transfer tube 50 and the insertion hole 11 and prevent water from entering and the gap humus. doing. Further, the pressure resistance of the heat exchanger 1C is improved.

The brazing method of the heat exchanger 1C according to the third embodiment is different from the brazing material 40 except that the brazing material 40 penetrates into the gap between the heat transfer tube 50 and the insertion hole 11 formed by the protrusion 53. It is similar to the first embodiment. Therefore, the description of the brazing method of the heat exchanger 1C according to the third embodiment will be omitted.

As described above, in the heat exchanger 1C according to Embodiment 3 of the present invention, the heat transfer tube 50 includes the protrusion 53 extending in the tube axis direction. As a result, similar to the first and second embodiments, a space where the brazing material 40 permeates into the insertion hole 11 can be secured between the heat transfer tube 50 and the insertion hole 11. As a result, in the heat exchanger 1C, the brazing material 40 can sufficiently penetrate into the headers 10R and 10L, and the headers 10R and 10L and the heat transfer tube 50 can be brazed with sufficient strength.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in Embodiment 1-3, groove 12, projections 13 and 53 have a semicircular shape in the YZ plane cross section, but the present invention is not limited to this. In the present invention, as long as uneven portions are formed on the inner wall of the insertion hole 11 or the outer walls of the heat transfer tubes 20 and 50, and the uneven portions extend in the tube axial direction of the heat transfer tubes 20 and 50, their cross-sectional shape Is optional.

FIG. 12 is an enlarged plan view of a modified example of the insertion hole 11 included in the header 10R included in the heat exchanger according to Embodiment 1 of the present invention. In FIG. 12, the same area as the IV area shown in FIG. 1 is enlarged.

As shown in FIG. 12, the groove 62 is formed in an arc shape in the YZ plane cross section. The circular arc projects from the inner walls 611 and 612 of the insertion hole 61 to the +Y side or the −Y side, that is, to the outside of the hole. A brazing material 40 is filled in the groove 62.

Thus, the grooves 12, 62 may be wholly or partially arcuate in the YZ plane cross-sectional view, that is, in the transverse cross-section, and the projections 13, 53 are similarly wholly or partially. It may have an arc shape. Furthermore, the grooves 12, 62 and the protrusions 13, 53 may be semi-elliptical or rectangular in cross-sectional view.

Further, as shown in FIG. 12, the number of the grooves 12, 62 and the protrusions 13, 53 is arbitrary, and the number of the grooves 12, 62, the protrusions 13, 53 may be only one or may be plural. Good.

Further, in the third embodiment, the heat transfer tube 50 has the protrusion 53. However, the present invention is not limited to this. As described above, in the present invention, the uneven portions are formed on the inner walls of the insertion holes 11, 61 or the outer walls of the heat transfer tubes 20, 50, or the uneven portions are formed on both the inner wall of the insertion holes 11 and the outer walls of the heat transfer tubes 20, 50. Is formed, and further, those uneven portions may extend in the tube axis direction of the heat transfer tubes 20, 50. Therefore, the heat transfer tube 50 may have the groove 52.

FIG. 13 is an enlarged plan view of the insertion hole 11 of the header 10R in which the modification of the heat transfer tube 50 of the heat exchanger according to Embodiment 3 of the present invention is inserted.

As shown in FIG. 13, the heat transfer tube 50 may have a groove 52 having a semicircular cross section. In this case, when the heat transfer tube 50 has a flat tube cross section, that is, when the tube cross section has an elongated rectangular shape in which both ends in the longitudinal direction are rounded into semicircles, the groove 52 has the rectangular shape. Is preferably formed on the side in the longitudinal direction. The groove 52 is preferably recessed from the outer circumference of the tube to the inner circumference of the tube. Although not shown, the groove 52 may be formed in the same region as the protrusion 53 of the third embodiment, that is, in the region from the end surface of the heat transfer tube 50 to the distance L. Even in such a configuration, the brazing material 40 can penetrate into the insertion hole 11 to form a brazing fillet protruding to the peripheral edge of the opening.

The groove 52 may be formed over the entire tube axis direction of the heat transfer tube 50. The same applies to the protrusion 53 of the third embodiment. Also in this form, the brazing material 40 can be permeated into the insertion hole 11.

In the first to third embodiments, the heat transfer tubes 20 and 50 have a flat tube cross section. However, when the shapes of the entire tube cross section, that is, the grooves 52 and the projections 53 are formed, the grooves 52 and the projections 53 are excluded. The overall shape is arbitrary as long as it can be inserted into the insertion holes 11 and 61. For example, the heat transfer tubes 20 and 50 may have a circular tube cross section. In other words, the heat transfer tubes 20 and 50 may be circular tubes.

Further, in Embodiments 1-3, the inside of the heat transfer tubes 20 and 50 is partitioned by the plurality of partition walls 21, but the internal structure of the heat transfer tubes 20 and 50 is arbitrary. For example, the heat transfer tube 20 may have one internal space without being partitioned by the partition wall 21.

In Embodiment 1-3, the headers 10R and 10L are formed in a hollow rectangular parallelepiped shape. However, in the present invention, the outer shapes of the headers 10R and 10L are arbitrary, as long as the headers 10R and 10L include the outer portion having the flow passages through which the fluid flows. In addition, the shape of the flow path also includes headers 10R and 10L each having an insertion hole penetrating from the outer shell portion to the flow path, and an uneven portion formed on the inner wall of the insertion hole and extending in the penetrating direction of the insertion hole. To the extent it is optional. For example, the headers 10R and 10L may be formed in a hollow cylindrical shape. Further, the flow paths inside the headers 10R and 10L may be partitioned by partition walls, or may have a plurality of flow paths by incorporating another member.

1A-1C heat exchanger, 10R, 10L header, 11 insertion hole, 12 groove, 13 protrusion, 20 heat transfer tube, 21 partition wall, 30 fin, 31 notch, 40 brazing material, 50 heat transfer tube, 52 groove, 53 protrusion, 61 insertion hole, 62 groove, 100 refrigerant inflow/outlet port, 111-114, 611, 612 inner wall, L distance, T thickness.

Claims (10)

The outer shell,
A flow path formed inside the outer shell, through which a fluid flows,
An insertion hole that penetrates from the outer shell portion to the flow path and causes the fluid to flow between the heat transfer tube and the flow path by inserting a heat transfer tube,
An uneven portion formed on the inner wall of the insertion hole and extending in the penetrating direction of the insertion hole,
Header with. The concavo-convex portion has an arc shape in a hole cross-sectional view that crosses the insertion hole,
The header according to claim 1. The uneven portion is recessed from the inner wall of the insertion hole to the outside of the insertion hole, and has a groove shape linearly extending in the penetrating direction.
The header according to claim 1 or 2. The concavo-convex portion projects from the inner wall of the insertion hole to the inside of the insertion hole, and has a shape of a protrusion that linearly extends in the penetrating direction.
The header according to claim 1 or 2. A header according to any one of claims 1 to 4,
The heat transfer tube inserted into the insertion hole,
A brazing material filled in a gap formed between the uneven portion and the heat transfer tube, and joining the header and the heat transfer tube,
With a heat exchanger. An outer shell part, a heat transfer tube formed inside the outer shell part, which is connected to a header provided with a flow path through which a fluid flows and an insertion hole penetrating from the outer shell part to the flow path,
An insertion portion inserted into the insertion hole,
An uneven portion provided in the insertion portion and extending in the tube axis direction,
Heat transfer tube. The concavo-convex portion has an arc shape in a tube sectional view,
The heat transfer tube according to claim 6. The concavo-convex portion is recessed from the outer circumference of the tube to the inner circumference of the tube, and has a groove shape linearly extending in the tube axial direction.
The heat transfer tube according to claim 6. The concavo-convex portion further protrudes from the outer circumference of the pipe to the outside of the pipe, and has a shape of a protrusion that linearly extends in the pipe axial direction,
The heat transfer tube according to claim 6. A heat transfer tube according to any one of claims 6 to 9,
The header in which the insertion portion is inserted into the insertion hole,
A brazing material filled in a gap formed between the uneven portion and the heat transfer tube, and joining the header and the heat transfer tube,
With a heat exchanger.

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