JP4221260B2 - Heat exchanger and manufacturing method thereof - Google Patents

Description

  The present invention relates to a heat exchanger and a manufacturing method thereof, and more particularly to a plate heat exchanger and a manufacturing method thereof.

  Conventionally, as one type of heat exchanger, there is a plate-type heat exchanger in which a cooling fluid and a fluid to be cooled are circulated in layers to perform heat exchange.

  This type of heat exchanger 1 includes, for example, as shown in FIG. 5, corrugated fins 2 and plates 3 that are alternately stacked, and a first header 4 that is connected to an end of the corrugated fin 2. In order to change the flow direction of the fluid, a distributor 5 provided at the end of the corrugated fin 2 and a second header 6 connected to the distributor 5 are schematically configured.

  The heat exchanger 1 is manufactured by sandwiching the end portions of the corrugated fins 2 with the side bars 7 and brazing the contact portions of the side bars 7 and the plate 3 together. 6 was welded (for example, refer to Patent Document 1).

  Further, as shown in FIG. 6, another heat exchanger 10 includes a double pipe 13 formed by providing a flat inner pipe 12 in a flat outer pipe 11, an outer pipe 11 and an inner pipe 11. The inner fin 15 inserted into the flow path 14 formed between the pipes 12 and the inlet / outlet pipe 17 to the flow path 14 connected to the long face 16 side of the both ends of the outer pipe 11 are roughly configured.

  The heat exchanger 10 is manufactured after the two outer plates 11 and the inner tube 12 are separately flattened by brazing each of the two plates, and the inner tube 12 is installed inside the outer tube 11. End caps (not shown) are attached to both ends of the outer tube 11 and the inner tube 12, and the inlet / outlet tube 17 is joined to the long surface 16 side of both ends of the outer tube 11 (for example, Patent Documents). 2).

Japanese Utility Model Publication No. 55-167084 Japanese Utility Model Publication No. 58-52462

  However, in the case of each of the heat exchangers 1 and 10 described above, the number of parts, the number of joints, and the number of manufacturing steps are large, and the brazing operation is required. Therefore, the manufacturing takes time and the manufacturing cost is reduced. There is a problem that fluid leakage is likely to occur.

  In the case of the former heat exchanger 1, the corrugated fins 2 and the plate 3 are laminated and integrally brazed, and the pressure cannot be detected in units of one unit. There is a problem that it is difficult to detect the location and it is difficult to improve the reliability of the product.

  Furthermore, in the case of the latter heat exchanger 10, the inlet / outlet pipe 17 to the flow path 14 is connected to the long surface 16 side of the outer pipe 11, so that there is sufficient fluid in the portion 18 on the opposite side of the connecting / exiting pipe 17 connection location. There was a risk that the flow distribution in the flow path 14 would not be uniform and the heat exchange capacity would be insufficient.

  The present invention has been made to solve the above-described problems, and can reduce the number of parts, joint locations, and manufacturing man-hours, and can improve the reliability and heat exchange performance of the product and its heat exchanger. A manufacturing method is provided.

A heat exchanger according to the present invention includes a heat transfer plate composed of a double tube in which a flat inner tube is provided in a flat outer tube, and a flow path formed between the outer tube and the inner tube. A fluid inlet / outlet port is provided on the short side of the outer pipe, and the flat double pipe presses the cylindrical double pipe at the same time, and connects the ends of the outer pipe and the inner pipe to each other. It is formed by joining and closing both ends of the flow path .

  Moreover, the manufacturing method of the heat exchanger according to the present invention includes a step of forming one cylindrical body from one plate, a step of pressing the cylindrical body to form a flat cylindrical body, The method includes a step of closing both end portions of the cylindrical body, and a step of forming an inlet / outlet of a fluid flowing through the inside of the flat cylindrical body on a short surface side of the flat cylindrical body.

Furthermore, the method for manufacturing a heat exchanger according to the present invention includes a step of forming a cylindrical double tube from two plates, and simultaneously pressing the cylindrical double tube to form a flat double tube. Joining the ends of the outer tube and the inner tube of the flat double tube, and closing both ends of the flow path formed between the outer tube and the inner tube; And a step of forming an inlet / outlet of the channel on the short surface side of the outer tube so that the channel on the short side can function as a tank .

  According to the heat exchanger according to the present invention, since the flow rate distribution in the flow path can be kept uniform, the heat exchange performance can be improved.

  Moreover, according to the manufacturing method of the heat exchanger which concerns on this invention, a number of parts, a joining location, and manufacturing man-hours can be reduced, and reduction of manufacturing cost is attained. Furthermore, since the occurrence of leakage can be suppressed and the pressure can be reliably detected, various excellent effects such as improvement of product reliability can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the case where the present invention is applied to an exhaust heat recovery type heat exchanger will be described.

  FIGS. 1 and 2 show the exhaust heat recovery type heat exchanger 21, and a flat heat transfer plate 22 is laminated on the exhaust heat recovery type heat exchanger 21. The heat transfer plate 22 includes a double tube 25 in which a flat inner tube 24 is provided in a flat outer tube 23, and a flat cylindrical air flow path 26 (see FIG. 3) between the outer tube 23 and the inner tube 24. (B) is formed. Exhaust gas flow paths 27 are formed between the heat transfer plates 22 and in the inner pipe 24 of the heat transfer plates 22, and corrugated fins 28 are inserted into the exhaust gas flow paths 27 in order to increase heat transfer efficiency. Nozzles 30 formed by drawing are attached to diagonal positions on the short surface 29 side of the outer tube 23 of the heat transfer plate 22, and the nozzles 30 are respectively provided with air inlet headers 32, An air outlet header 33 is attached. Further, an exhaust gas inlet header 34 and an exhaust gas outlet header 35 are attached to both ends of the heat transfer plate 22, respectively.

  In such a configuration, the high-temperature exhaust gas flows through the exhaust gas flow path 27 via the exhaust gas inlet header 34 and exchanges heat with the air flowing through the air flow path 26 via the air inlet header 32. As a result, the air recovers heat from the high-temperature exhaust gas and is supplied to a predetermined location via the air outlet header 33, and the exhaust gas that has become low temperature is discharged to the outside via the exhaust gas outlet header 35. In this case, since the nozzle 30 is attached to the short surface 29 side of the outer tube 23 and the air flow path 26 on the short surface 29 functions as a tank, air is uniformly distributed in the air flow path 26, The exchange performance can be improved.

  Next, a method for manufacturing the exhaust heat recovery type heat exchanger 21 will be described with reference to FIGS. 1 and 3.

  As shown in FIG. 3 (a), each plate is bent into a cylindrical shape, and its peripheral portions 36 and 37 are welded to form cylindrical outer tube 23 and inner tube 24, respectively. After that, the inner tube 24 is provided in the outer tube 23 to form a cylindrical double tube 25. As shown in FIG. 3 (b), the double pipe 25 is pressed, processed into a flat cylindrical shape, and the nozzle 30 is welded and joined to the diagonal position on the short surface 29 side of the outer pipe 23, Both ends of the outer tube 23 and the inner tube 24 are welded and joined, and both ends of the air flow path 26 are closed. Thereafter, the heat transfer plates 22 thus formed are alternately laminated with the corrugated fins 28, the corrugated fins 28 are inserted into the inner tube 24, and the air inlet header 32 and the air outlet header are inserted into the nozzle 30 via the header plate 31. 33 and the exhaust gas inlet header 34 and the exhaust gas outlet header 35 are attached to both ends of the heat transfer plate 22.

  As described above, since the outer tube 23 and the inner tube 24 can be simultaneously formed from one plate, the number of parts and the joint location can be reduced, and only the welding joint is performed without brazing. Can also be produced. Therefore, the number of manufacturing steps can be reduced, the manufacturing cost can be reduced, and the occurrence of fluid leakage can be suppressed. Furthermore, since the pressure can be detected in units of the heat transfer plate 22, a defective portion can be surely found in advance, and the reliability of the product can be improved. Furthermore, since the number of stacked heat transfer plates 22 can be easily changed and the size of the heat transfer plate 22 can be easily changed, it is possible to flexibly cope with a change in product design.

  In the above embodiment, the case where the heat transfer plate 22 is composed of the double tube 25 has been described. However, the present invention can be applied to the case of the single tube 38 as shown in FIGS. 4 (a) and 4 (b). It can be implemented. Further, the mounting position of the nozzle 30 is not limited to the diagonal position as long as it is on the short surface 29 side, and is provided on the same side as shown in FIG. 4B, for example. Also good.

  Furthermore, you may manufacture the outer tube | pipe 23 and the inner tube | pipe 24 using the wave plate shape | molded in the waveform. In this case, since the heat exchange performance can be sufficiently enhanced without inserting the corrugated fins 28 into the exhaust gas flow path 27, the number of parts can be further reduced, and the above-described effects can be further enhanced.

  Furthermore, in the above-described embodiment, the exhaust heat recovery type heat exchanger 21 has been described. However, this is merely an example, and the present invention can be applied to other heat exchangers such as an oil cooler and an intercooler. The fluid to be heat exchanged may be liquids or liquids and gases.

It is a disassembled perspective view which shows the heat exchanger which concerns on embodiment of this invention. It is a front view which shows the heat-transfer plate in embodiment of this invention. (A) And (b) is a perspective view which shows the manufacture procedure of the heat exchanger which concerns on embodiment of this invention together. (A) And (b) is a perspective view which shows the manufacture procedure of the other heat exchanger which concerns on embodiment of this invention. It is a perspective view which shows a prior art example. It is a front view which shows another prior art example.

Explanation of symbols

21 Heat recovery type heat exchanger 22 Heat transfer plate 23 Outer pipe 24 Inner pipe 25 Double pipe 26 Air flow path 29 Short face

Claims (2)

A heat transfer plate comprising a flat double tube in which a flat inner tube is provided in a flat outer tube, and an inlet / outlet for fluid flowing through a flow path formed between the outer tube and the inner tube, respectively Provided on the short surface side of the outer pipe, the flat double pipe presses the cylindrical double pipe at the same time, joins the ends of the outer pipe and the inner pipe, and A heat exchanger characterized by being formed by closing both ends . Forming a cylindrical double tube from two plates;
Simultaneously pressing the cylindrical double pipe to form a flat double pipe;
Joining each end of the outer tube and the inner tube of the flat double tube, and closing both ends of a flow path formed between the outer tube and the inner tube;
Forming the inlet / outlet of the flow path on the short face side of the outer pipe so that the short face side flow path functions as a tank;
A method for producing a heat exchanger, comprising:

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