JP2018017424A - Manufacturing method of heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a heat exchanger enabling brazing a fin in a state where the fin comprising a porous body contacts to a flat tube without any gaps.SOLUTION: A heat exchanger is configured such that a plurality of flat tubes 20 where a medium subjected to heat exchange with air flows therein are disposed in a laminated state with intervals as an air flow passage 40, and fins 30 for heat transfer comprising a porous body are mounted between the respective flat tubes 20. A manufacturing method of the heat exchanger comprises: making intervals between adjacent flat tubes 20 different between an inlet side and outlet side of the air flow passage 40; inserting the fins 30 into the air flow passage 40 from a side with a wide interval toward a side with a narrow interval to contact them with the flat tubes 20; and brazing the fins to the flat tubes 20 in a pressurized manner.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat exchanger such as a heat exchanger for an air conditioner or a radiator for an automobile, and in particular, a heat exchanger having a structure in which fins made of a porous body are provided between a plurality of flat tubes. It relates to a manufacturing method.

  A porous body having a three-dimensional network structure having a three-dimensionally connected skeleton and pores connected in three dimensions by the skeleton allows a fluid such as gas or liquid to pass through the connected pores. At the same time, it is used in filters (Patent Documents 1 and 2 etc.) for filtering these fluids, and catalyst carriers and the like (Patent Document 2 etc.) for reforming these fluids with a catalyst supported on the skeleton surface. Recently, utilization of heat exchanger fins as heat transfer fins has been promoted by utilizing the size of the surface area (Patent Document 3).

JP 05-339605 A Japanese Patent Laid-Open No. 08-020831 JP 2005-326136 A

  Patent Document 3 discloses a heat exchanger having a structure in which fins made of a porous body are provided between a plurality of flat tubes and the ends of the flat tubes are communicated with each other by a header. In such a heat exchanger, in order to ensure sufficient heat exchange performance, it is desirable that the flat tube and the fin be joined in a larger area metallurgically by brazing. In addition, in order to simplify the manufacturing, it is required to braze the headers together. However, there is a problem that a gap is generated between the flat tube and the fin due to variations in the size of the fin and the flat tube, resulting in a decrease in thermal conductivity.

  From the above, the present invention is capable of brazing the flat tube with the fins made of a porous body in contact with no gap, and as a result, the heat exchange can improve the efficiency of the heat exchange due to the high thermal conductivity. It aims at providing the manufacturing method of a vessel.

  In the method for manufacturing a heat exchanger according to the present invention, a plurality of flat tubes in which a medium to be exchanged with air is flowed are disposed in a stacked state with air flow passages therebetween, and a porous body is provided between the flat tubes. A heat exchanger manufacturing method equipped with heat transfer fins comprising: an interval between the adjacent flat tubes is made different between an inlet side and an outlet side of the air flow passage; The flat tube is inserted into the air flow passage from the wide side toward the narrow side to contact the flat tube and brazed to the flat tube while being pressurized.

  According to the present invention, the fins are inserted into the air flow path between the adjacent flat tubes from the wide side toward the narrow side, so that the fins are brazed with no gap therebetween. can do. As a result, high thermal conductivity is obtained, and the efficiency of heat exchange is improved.

  In the present invention, in order to make the interval between adjacent flat tubes different between the inlet side and the outlet side of the air flow passage, the installation angle of the flat tube is adjusted, or the thickness of the flat tube is adjusted Is possible.

  The present invention includes a form in which the side cross-sectional shape and dimensions of the fins are the same as the side cross-sectional shape of the airflow passage. According to this aspect, it is possible to reliably achieve contact of the fins with no gap to the flat tube. Further, the contact pressure of the fin to the flat tube can be made uniform from the inlet side to the outlet side of the flat tube, and the brazing strength is less likely to be biased.

  According to the present invention, a heat exchanger capable of brazing a flat tube with a fin made of a porous body in contact with no gap, resulting in improved heat exchange efficiency due to high thermal conductivity is manufactured. The effect that it can be done is produced.

It is a front view of the heat exchanger which concerns on one Embodiment of this invention. It is sectional drawing which shows the process which brazes a fin between flat tubes in the manufacturing method of one Embodiment, (a) The state which has inserted the fin between flat tubes, (b) It brazes a fin to a flat tube Indicates the attached state. It is sectional drawing which shows the process of brazing between flat tubes in the case of using the flat tube of other embodiment, (a) The state which has inserted the fin between flat tubes, (b) Flattening a fin Shows the state brazed to the tube.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[1] Structure of Heat Exchanger FIG. 1 shows a heat exchanger 1 manufactured by a manufacturing method according to an embodiment. The heat exchanger 1 includes a pair of left and right headers 10 in the figure, a plurality of flat tubes 20 arranged in parallel between the headers 10, and heat transfer fins mounted between the flat tubes 20. 30.

  The header 10 has a hollow pipe shape, and a refrigerant is introduced into one header 10. The refrigerant flows through each flat tube 20 and is led into the other header 10. As shown in FIG. 2, the flat tube 20 has a plurality of refrigerant passages 21 penetrating in the longitudinal direction, and the end portions of the flat tube 20 are in a state where the refrigerant passages 21 communicate with each other in the headers 10. Is fixed to the header 10 by brazing.

  The heat exchanger 1 is applied to, for example, a radiator for an automobile, and in a state where air flows from the front side to the back side (in FIG. 1, from the front side to the back side) in the air flow passage 40 between the flat tubes 20. Installed. As shown in FIG. 1, the flat tube 20 is disposed in a state where the air flow passage 40 is opened and stacked vertically at equal intervals, and the fins 30 are attached to the air flow passage 40 in a filled state. The fins 30 are fixed to the upper and lower flat tubes 20 by brazing.

  The fin 30 is an aluminum-based porous body having a three-dimensional network structure in which a three-dimensionally connected aluminum skeleton is formed and pores connected in three dimensions are formed by the skeleton. . Such a porous body can be obtained by a well-known method, for example, by forming a metal layer on the surface of a foamed resin skeleton by a method such as electroplating or spray coating, and then heating to decompose and remove the resin. it can. Since the aluminum-based porous body having such a three-dimensional network structure has a large contact area with a fluid, it is extremely effective as a heat transfer member or a heat absorption member of a heat exchanger.

  According to this heat exchanger 1, the temperature of the refrigerant flowing from the refrigerant introduction side header 10 through the flat tubes 20 and flowing into the lead-out side header 10 is transmitted to the fins 30 when flowing through the flat tubes 20, and the fins 30. The refrigerant exchanges heat with the air that is transmitted through the air and cools the refrigerant.

[2] Heat Exchanger Manufacturing Method The heat exchanger 1 is manufactured by simultaneously brazing the flat tube 20 to the header 10 and brazing the fins 30 to the flat tube 20. In performing this brazing operation, in this embodiment, the flat tube 20 is installed in parallel in the width direction (left-right direction in FIG. 1), but as shown in FIG. 2, it is perpendicular to the depth direction (vertical direction in which the header 10 extends). 2 and the left and right directions in FIG. 2 are slightly inclined alternately with respect to the depth direction, and the intervals between the flat tubes 20 adjacent to each other on the inlet side and the outlet side of the air flow passage 40 are different. Install it in a closed state. In FIG. 2, A indicates the air inlet side, and B indicates the outlet side. Thereby, the side cross-sectional shape of the air flow passage 40 becomes a wedge shape. The inclination angle of the flat tube 20 is about 1 to 5 ° with respect to the depth direction.

  In FIG. 2, all the flat tubes 20 are inclined, but every other flat tube 20 is inclined in the opposite direction, and the flat tubes 20 between the inclined flat tubes 20 are installed in parallel with the depth direction. The side cross-sectional shape of the air flow passage 40 between the flat tubes 20 adjacent in the vertical direction may be a wedge shape.

  Further, as shown in FIG. 2, the fin 30 is used in which the side sectional shape and dimensions are processed into a wedge shape similar to the side sectional shape of the air flow passage 40.

  In order to perform brazing of the flat tube 20 to the header 10 and brazing of the fins 30 to the flat tube 20 at the same time, the right and left temporarily fixed with the brazing material applied to their joint surfaces in advance. First, the flat tubes 20 are installed between the headers 10 with the depth direction alternately inclined as shown in FIG. Next, the fin 30 is inserted into the air flow passage 40 between the flat tubes 20.

  As shown in FIG. 2A, the fins 30 are inserted on the side where the space between the flat tubes 20 is wide so that the side cross-sectional shape coincides with the air flow passage 40. Insert into the flow passage 40. That is, the fins 30 are inserted from the thin end toward the air flow passage 40 from the wide side toward the narrow side between the flat tubes 20. Accordingly, the fins 30 are alternately inserted into the air flow passage 40 from the inlet side and the outlet side.

  When the fin 30 is inserted in this way, the upper and lower surfaces of the fin 30 come into contact with the flat surfaces of the upper and lower flat tubes 20 as shown in FIG. In this state, the fin 30 is brazed to the flat tube 20, and the flat tube 20 is brazed to the header 10 together with the fin 30. Brazing is achieved by heating the entire heat exchanger 1 to a brazing temperature at which the brazing material melts, and then cooling.

[3] Effects of one embodiment According to the present embodiment, the flat tubes 20 are inserted into the air flow passages 40 between the adjacent flat tubes 20 by inserting the fins 30 from the wide side toward the narrow side. On the other hand, it can braze in the state which made the fin 30 contact without gap. As a result, high thermal conductivity is obtained, and the efficiency of heat exchange is improved.

  In the present embodiment, since the side cross-sectional shape and dimensions of the fin 30 are the same as the side cross-sectional shape of the airflow passage 40, it is possible to reliably achieve the contact of the fin 30 with the flat tube 20 without a gap. . Thereby, the contact pressure of the fins 30 to the flat tube 20 can be made uniform from the inlet side to the outlet side of the flat tube 20, and as a result, the brazing strength is less likely to be biased and good brazing is possible. It becomes.

[4] Other Embodiments In the above embodiment, the installation angle in the depth direction of the flat tube 20 is inclined as means for making the interval between the adjacent flat tubes 20 different between the inlet side and the outlet side of the air flow passage 40. However, it is also possible to adjust the thickness of the flat tube 20 so as to gradually change from the inlet side to the outlet side, as shown in FIG.

  In the case of FIG. 3, all the flat tubes 20 arranged in the vertical direction are wedge-shaped in cross section, with the smaller thickness facing the inlet side and the depth direction being parallel. Therefore, all the air flow passages 40 have a wide inlet side and a narrow outlet side, and the fins 30 are inserted from the inlet side and brazed while pressurizing the fins 30 in the insertion direction as in the above embodiment.

  The present invention can be used as a method of manufacturing a heat exchanger such as a heat exchanger for an air conditioner or a radiator for an automobile.

DESCRIPTION OF SYMBOLS 1 ... Heat exchanger 20 ... Flat tube 30 ... Fin 40 ... Air flow path A ... Inlet side of air flow path B ... Outlet of air flow path

Claims (4)

A plurality of flat tubes in which a medium that exchanges heat with air is flowed are arranged in a stacked state with air flow passages therebetween, and heat transfer fins made of a porous body are mounted between the flat tubes. A method of manufacturing a heat exchanger,
The interval between the adjacent flat tubes is different between the inlet side and the outlet side of the air flow passage,
A method of manufacturing a heat exchanger, wherein the fins are inserted into the air flow passage from the wide side toward the narrow side to contact the flat tube and brazed to the flat tube while being pressurized.   The method for manufacturing a heat exchanger according to claim 1, wherein an interval between the adjacent flat tubes is made different between an inlet side and an outlet side of the air flow passage by adjusting an installation angle of the flat tubes.   The manufacturing method of the heat exchanger of Claim 1 which makes the space | interval between this adjacent flat tube differ by the inlet side and the exit side of the said air flow path by adjusting the thickness of the said flat tube.   The manufacturing method of the heat exchanger in any one of Claims 1-3 which made the side cross-sectional shape and dimension of the said fin the same as the side cross-sectional shape of the said air flow path.

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