Heat Exchange Element

Abstract

This heat exchange element is formed by stacking a plurality of heat transfer plates (1), each of the heat transfer plates (1) having a heat exchange unit (5) for allowing air that has passed by one stacking-direction side of the plurality of heat transfer plates (1) and air that has passed by the other stacking-direction side of the heat transfer plates (1) to pass therethrough in mutually opposite directions and carrying out heat exchange, header parts (6a, 6b) provided to the one side and the other side sandwiching the heat exchange unit (5) as seen along the stacking direction, and joining edge parts (25-28) provided along a side of the heat exchange unit (5) that does not touch the header parts (6a, 6b). The joining edge parts (25-28) provided to the stacked plurality of heat transfer plates (1) are brought into contact with one another and are joined to one another through ultrasonic welding. A first protrusion (16) that protrudes along the stacking direction, and a recess (15) into which a first protrusion (16) of an adjacent heat transfer plate fits, are formed on the joining edge parts (25-28).

Description

[Technical field]

[0001] The present disclosure relates to a counterflow type heat exchange element formed by stacking heat transfer plates.

[0002] In the counterflow type heat exchange element, there is a heat exchange element in which heat transfer plates formed of resin sheets are stacked. For example, Patent Document 1 discloses a heat exchange element formed into a hexagonal prism by stacking hexagonal shaped heat transfer plates. In the hexagonal prism heat exchange element, a part of the side surface becomes an inlet and outlet of the air to be exchanged. In addition, the edge portions of the heat transfer plate other than the edge portion facing the side surface that becomes the inlet and outlet of the air are joined to each other by the stacked heat transfer plates, thereby preventing air leakage from the heat exchange element. The edges are joined to each other by heat welding or adhesion using epoxy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-293862 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, ultrasonic welding is sometimes used to join heat transfer plates together. By using ultrasonic welding, it is possible to shorten the time required to join heat transfer plates together. In ultrasonic welding, ultrasonic vibrations are transmitted to the edges through a tool that holds the edges. When joining heat transfer plates together using ultrasonic welding, there is a problem in that the ultrasonic vibrations can cause the heat transfer plates to shift position.

[0005] The present disclosure has been made in consideration of the above, and aims to obtain a heat exchange element in which the heat transfer plates that constitute the heat exchange element do not shift in position even when the heat transfer plates are fixed to each other by ultrasonic welding, and the heat transfer plates can be accurately and easily positioned. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the object, the heat exchange element according to the present disclosure is a heat exchange element formed by stacking a plurality of heat transfer plates, the heat transfer plate having a heat exchange section for passing air passing on one side of the stacking direction of the plurality of heat transfer plates and air passing on the other side of the stacking direction in opposing directions to exchange heat, header sections provided on one side and the other side of the heat exchange section as viewed along the stacking direction, and a joint edge section provided along a side of the heat exchange section that does not contact the header section. The joint edges of the stacked plurality of heat transfer plates are in contact with each other and joined by ultrasonic welding, and the joint edge section has a first protrusion that is protruding along the stacking direction and a recess into which the first protrusion of the adjacent heat transfer plate fits. The header portion is formed with a base that is convex in the stacking direction and has a recess formed at its top, and a second protrusion that fits into the recess of the adjacent heat transfer plate. Effect of the Invention

[0007] According to the present disclosure, it is possible to obtain a heat exchange element in which the heat transfer plates constituting the heat exchange element are fixed to each other by ultrasonic welding without misalignment, and the heat transfer plates can be accurately and easily positioned to each other. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a heat exchange element according to a first embodiment; [Diagram 2] FIG. 1 is an exploded perspective view of a heat exchange element according to a first embodiment; [Diagram 3] FIG. 1 is a perspective view of a part of a heat exchange element according to a first embodiment; [Figure 4] FIG. 1 is a plan view of a first heat transfer plate according to the first embodiment; [Diagram 5] FIG. 1 is a plan view of a second heat transfer plate according to the first embodiment; [Figure 6] FIG. 1 is a partially enlarged cross-sectional view of a protrusion and a base portion of a heat exchange element according to a first embodiment; [Figure 7] FIG. 1 is a partially enlarged perspective cross-sectional view of a protrusion and a base portion of a heat exchange element according to a first embodiment; [Figure 8] FIG. 1 is a plan view of a base according to the first embodiment; [Figure 9]FIG. 1 is a partially enlarged cross-sectional view of a cone cover and a cone portion in a heat exchange element according to a first embodiment; [Figure 10] FIG. 1 is a partially enlarged perspective cross-sectional view of a cone cover and a cone portion in a heat exchange element according to a first embodiment; [Figure 11] FIG. 1 is a diagram showing a schematic configuration of a manufacturing apparatus for a heat exchange element according to a first embodiment. [Figure 12] FIG. 12 is a perspective cross-sectional view showing a state in which the guide pin shown in FIG. 11 is fitted into a protrusion. [Figure 13] FIG. 1 is a diagram showing a manufacturing process of a heat exchange element according to a first embodiment. [Figure 14] FIG. 1 is a diagram showing a manufacturing process of a heat exchange element according to a first embodiment. [Figure 15] FIG. 1 is a diagram showing a manufacturing process of a heat exchange element according to a first embodiment. [Figure 16] FIG. 1 is a diagram showing a manufacturing process of a heat exchange element according to a first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a heat exchange element according to an embodiment will be described in detail with reference to the drawings.

[0010] Embodiment 1 FIG. 1 is a perspective view of a heat exchange element according to the first embodiment. FIG. 2 is an exploded perspective view of the heat exchange element according to the first embodiment. FIG. 3 is a perspective view of a part of the heat exchange element according to the first embodiment. The heat exchange element 50 is formed into a hexagonal column as a whole by alternately stacking a first heat transfer plate 1 and a second heat transfer plate 2 each having a hexagonal shape. In the following description, the stacking direction of the first heat transfer plate 1 and the second heat transfer plate 2 is simply referred to as the stacking direction. Also, the vertical direction on the paper surface of FIG. 1 will be described as the vertical direction in the heat exchange element 50.

[0011] The heat exchange element 50 has six rectangular side surfaces, one of which serves as a first inflow surface 61 that serves as an air inlet for the inside of the heat exchange element 50. The side surface facing the opposite direction to the first inflow surface 61 serves as a first outflow surface 71 through which the air that has flowed in from the first inflow surface 61 flows out. An air passage 3 that connects the first inflow surface 61 and the first outflow surface 71 is formed inside the heat exchange element 50.

[0012] One of the two side surfaces adjacent to the first outlet surface 71 serves as a second inlet surface 62, which serves as an inlet for air to flow into the inside of the heat exchange element 50. The side surface facing the opposite direction to the second inlet surface 62 serves as a second outlet surface 72 through which the air flowing in from the second inlet surface 62 flows out. The first inlet surface 61 and the second outlet surface 72 are adjacent to each other. Inside the heat exchange element 50, an air passage 4 is formed that connects the second inlet surface 62 and the second outlet surface 72. Inside the heat exchange element 50, the air passage 3 and the air passage 4 do not intersect.

[0013] The heat exchange element 50 is provided, for example, inside a ventilation device, and allows the exhaust air flow from inside the room to the outside to pass through air duct 3, and the intake air flow from the outside to inside the room to pass through air duct 4, thereby enabling heat exchange between the intake air flow and the exhaust air flow.

[0014] FIG. 4 is a plan view of the first heat transfer plate in the first embodiment. The first heat transfer plate 1 has a hexagonal shape in a plan view. By laminating the first heat transfer plate 1 and the second heat transfer plate 2, the air passage 3 is formed on one side of the first heat transfer plate 1, and the air passage 4 is formed on the other side of the first heat transfer plate 1. The first heat transfer plate 1 is provided with a heat exchange section 5 that exchanges heat between the air passing through the air passage 3 and the air passing through the air passage 4. The heat exchange section 5 is formed in a rectangular region with the short sides being sides 1a and 1b that face the side of the heat exchange element 50 on which the first inflow surface 61, the first outflow surface 71, the second inflow surface 62, and the second outflow surface 72 are not formed. Although a detailed description of the structure is omitted, the heat exchange section 5 is formed with a corrugated shape having a plurality of projections and recesses. In the heat exchange section 5, the air passing through the air passage 3 and the air passing through the air passage 4 pass parallel to each other and in opposite directions.

[0015] The first heat transfer plate 1 is provided with a first header portion 6a having a triangular shape in a plan view. The first header portion 6a has a side 1c facing the first inflow surface 61 of the heat exchange element 50 and a side 1d facing the second outflow surface 72.

[0016] The first heat transfer plate 1 is formed with a second header portion 6b that is triangular in plan view. The second header portion 6b has a side 1e that faces the first outflow surface 71 of the heat exchange element 50 and a side 1f that faces the second inflow surface 62. The first header portion 6a and the second header portion 6b are provided on one side and the other side of the heat exchange portion 5. The sides 1a and 1b of the first heat transfer plate 1 are sides that do not contact the first header portion 6a and the second header portion 6b.

[0017] Ribs 8 are formed on the first header portion 6a and the second header portion 6b. The ribs 8 formed on the first header portion 6a extend from the side 1c toward the heat exchange portion 5. The ribs 8 formed on the first header portion 6a extend approximately parallel to the side 1d and allow the air that has flowed in from the first inflow surface 61, i.e., the side 1c side, to pass smoothly toward the heat exchange portion 5.

[0018] The ribs 8 formed on the second header portion 6b extend from the side 1e toward the heat exchange portion 5. The ribs 8 formed on the second header portion 6b extend approximately parallel to the side 1f, allowing the air from the heat exchange portion 5 to pass smoothly toward the side 1e.

[0019] The outer edge of the first header portion 6a is provided with a band-shaped flat portion 21 which is a band-shaped flat area extending along the side 1c. The outer edge of the first header portion 6a is provided with a band-shaped flat portion 22 which is a band-shaped flat area extending along the side 1d. In the first heat transfer plate 1, a step 41 is provided between the band-shaped flat portion 21 and the band-shaped flat portion 22 along the stacking direction to allow air to flow in from the side 1c and prevent air from flowing in from the side 1d. More specifically, the band-shaped flat portion 21 is formed at a position below the area where the rib 8 is formed, and the band-shaped flat portion 22 is formed at a position above the band-shaped flat portion 21. The band-shaped flat portion 21 and the area where the rib 8 is formed may be formed on the same plane.

[0020] The outer edge of the second header portion 6b is provided with a band-shaped flat portion 23 which is a band-shaped flat area extending along the side 1e. The outer edge of the second header portion 6b is provided with a band-shaped flat portion 24 which is a band-shaped flat area extending along the side 1f. In the first heat transfer plate 1, a step 42 is provided between the band-shaped flat portion 23 and the band-shaped flat portion 24 along the stacking direction to allow air to flow out from the side 1e and to prevent air from flowing out from the side 1f. More specifically, the band-shaped flat portion 23 is formed at a position below the area where the rib 8 is formed, and the band-shaped flat portion 24 is formed at a position above the band-shaped flat portion 23. The band-shaped flat portion 23 and the area where the rib 8 is formed may be formed on the same plane.

[0021] The heat exchange section 5 is provided at its outer edge with band-shaped flat sections 25 and 26, which are band-shaped flat regions extending along the side 1a. The band-shaped flat section 25 and the band-shaped flat section 26 are formed with a step 43 provided between them in their intermediate portions in the direction along the side 1a. The band-shaped flat section 26 is formed higher than the band-shaped flat section 25.

[0022] The outer edge of the heat exchange section 5 is provided with band-shaped flat sections 27, 28 which are band-shaped flat regions extending along the side 1b. The band-shaped flat section 27 and the band-shaped flat section 28 are formed with a step 44 provided between them in the middle in the direction along the side 1b. The band-shaped flat section 28 is formed higher than the band-shaped flat section 27. The first heat transfer plate 1 is shaped point-symmetrical with respect to the center position of the hexagonal shape in a plan view.

[0023] 5 is a plan view of the second heat transfer plate in the first embodiment. The second heat transfer plate 2 has a hexagonal shape in a plan view. The same components as those of the first heat transfer plate 1 are given the same reference numerals and detailed description is omitted. The second heat transfer plate 2 and the first heat transfer plate 1 are in a mirror image relationship.

[0024] By laminating the first heat transfer plate 1 and the second heat transfer plate 2, the air passage 4 is formed on one side of the second heat transfer plate 2, and the air passage 3 is formed on the other side of the second heat transfer plate 2. The second heat transfer plate 2 is provided with a heat exchange section 5 that exchanges heat between the air passing through the air passage 3 and the air passing through the air passage 4. In the second heat transfer plate 2, the heat exchange section 5 is formed in a rectangular region with the short sides being sides 2a and 2b that face the side of the heat exchange element 50 on which the first inflow surface 61, the first outflow surface 71, the second inflow surface 62, and the second outflow surface 72 are not formed.

[0025] The second heat transfer plate 2 is provided with a third header portion 6c having a triangular shape in a plan view. The third header portion 6c has a side 2c facing the first inflow surface 61 of the heat exchange element 50 and a side 2d facing the second outflow surface 72.

[0026] The second heat transfer plate 2 is formed with a fourth header portion 6d that is triangular in plan view. The fourth header portion 6d has a side 2e facing the first outflow surface 71 of the heat exchange element 50 and a side 2f facing the second inflow surface 62. The third header portion 6c and the fourth header portion 6d are provided on one side and the other side of the heat exchange portion 5. The sides 2a and 2b of the second heat transfer plate 2 are sides that do not contact the third header portion 6c and the fourth header portion 6d.

[0027] Ribs 8 are formed on the third header portion 6c and the fourth header portion 6d. The ribs 8 formed on the third header portion 6c extend from the side 2d toward the heat exchange portion 5. The ribs 8 formed on the third header portion 6c extend substantially parallel to the side 2c, allowing the air from the heat exchange portion 5 to pass smoothly toward the side 2d.

[0028] The ribs 8 formed on the fourth header portion 6d extend from the side 2f toward the heat exchange portion 5. The ribs 8 formed on the fourth header portion 6d extend approximately parallel to the side 2e and allow the air that has flowed in from the second inlet surface 62, i.e., the side 2f side, to pass smoothly toward the heat exchange portion 5.

[0029] The third header portion 6c has an outer edge provided with a band-shaped flat portion 31 which is a band-shaped flat area extending along the side 2c. The third header portion 6c has an outer edge provided with a band-shaped flat portion 32 which is a band-shaped flat area extending along the side 2d. In the second heat transfer plate 2, a step 51 is provided between the band-shaped flat portion 31 and the band-shaped flat portion 32 along the stacking direction to allow air to flow out from the side 2d and prevent air from flowing out from the side 2c. More specifically, the band-shaped flat portion 32 is formed at a position below the area where the rib 8 is formed, and the band-shaped flat portion 31 is formed at a position above the band-shaped flat portion 32. The band-shaped flat portion 32 and the area where the rib 8 is formed may be formed on the same plane.

[0030] The outer edge of the fourth header portion 6d is provided with a band-shaped flat portion 33 which is a band-shaped flat area extending along the side 2e. The outer edge of the fourth header portion 6d is provided with a band-shaped flat portion 34 which is a band-shaped flat area extending along the side 2f. In the second heat transfer plate 2, a step 52 is provided between the band-shaped flat portion 33 and the band-shaped flat portion 34 along the stacking direction to allow air to flow in from the side 2f and to prevent air from flowing in from the side 2e. More specifically, the band-shaped flat portion 34 is formed at a position below the area where the rib 8 is formed, and the band-shaped flat portion 33 is formed at a position above the band-shaped flat portion 34. The band-shaped flat portion 34 and the area where the rib 8 is formed may be formed on the same plane.

[0031] The heat exchanger 5 is provided at its outer edge with band-shaped flat portions 35 and 36, which are band-shaped flat regions extending along the side 2a. The band-shaped flat portion 35 and the band-shaped flat portion 36 are formed with a step 53 provided between them in their intermediate portions in the direction along the side 2a. The band-shaped flat portion 35 is formed higher than the band-shaped flat portion 36.

[0032] The outer edge of the heat exchange section 5 is provided with band-shaped flat sections 37, 38 which are band-shaped flat regions extending along the side 2b. The band-shaped flat section 37 and the band-shaped flat section 38 are formed with a step 54 provided between them in the middle in the direction along the side 2b. The band-shaped flat section 37 is formed higher than the band-shaped flat section 38. The second heat transfer plate 2 is shaped point-symmetrical with respect to the center position of the hexagonal shape in a plan view.

[0033] Next, the protrusions 13, the base 14, the cone cover 15, and the cone 16 formed on the first heat transfer plate 1 and the second heat transfer plate 2 will be described.

[0034] The protrusions 13 and the base 14 are formed on the header portions 6a, 6b, 6c, and 6d. Fig. 6 is a partially enlarged cross-sectional view of the protrusions and base in the heat exchange element according to the first embodiment. Fig. 7 is a partially enlarged perspective cross-sectional view of the protrusions and base in the heat exchange element according to the first embodiment. Fig. 8 is a plan view of the base in the first embodiment.

[0035] The protrusion 13 is formed so as to be convex downward. The protrusion 13 is a second convex portion. The back surface of the protrusion 13 is recessed. Returning to FIG. 4 and FIG. 5, a plurality of protrusions 13 are formed along the sides 1c, 1e, 2d, and 2f which are the inlets and outlets of air. A plurality of protrusions 13 are formed for each of the sides 1c, 1e, 2d, and 2f. The protrusions 13 are formed at positions which divide the length of each of the sides 1c, 1e, 2d, and 2f at equal intervals. The ratio of the height of the protrusion 13 to the diameter at the base of the protrusion 13 is 1 or less. This ratio can prevent holes from being formed due to the material becoming too thin when the heat transfer plates 1 and 2 are formed by vacuum forming.

[0036] As shown in Figs. 6 and 7, the base 14 is formed so as to be convex upward. The base 14 has a trapezoidal cross-sectional shape. A flat area is provided at the top of the base 14, and a downwardly recessed recess 14a is formed in the flat area. As shown in Fig. 8, the planar shape of the base 14 is a rhombus. The recess 14a has an elongated hole shape with the longitudinal direction being the direction toward the center of the heat transfer plates 1, 2 in a plan view. The width of the recess 14a along the short side direction is a width into which the protrusion 13 fits.

[0037] The pedestal 14 is provided so that the longer of the two diagonals of the rhombus is parallel to the sides 1d, 1f, 2c, and 2e along which the pedestal 14 is located. In other words, the pedestal 14 may be provided so that the longer of the two diagonals of the rhombus is aligned with the air flow direction. The pedestal 14 is provided on a straight line that is approximately parallel to the air flow direction, as close as possible to the band-shaped flat portions 22, 24, 31, and 33, but with a gap therebetween, and at a position away from the band-shaped flat portions 22, 24, 31, and 33 so that the pedestal 14 does not overlap with the band-shaped flat portions 22, 24, 31, and 33. In other words, in this embodiment, the pedestal 14 is disposed on a straight line that is approximately parallel to the band-shaped flat portions 22, 24, 31, and 33.

[0038] The protrusion 13 and the base 14 are formed at a position where they overlap each other in a plan view when the first heat transfer plate 1 and the second heat transfer plate 2 are stacked. As shown in Figs. 6 and 7, when the heat transfer plates 1 and 2 are stacked, the flat area of ​​the top of the base 14 abuts against the heat transfer plates 1 and 2 stacked above. The protrusion 13 fits into the recess 14a of the base 14. Since the protrusion 13 fits into the recess 14a, it is not exposed to the air passages 3 and 4. The protrusion 13 may be convex upward and the base 14 may be convex downward.

[0039] As shown in Fig. 4 and Fig. 5, the cone cover 15 is formed on the band-shaped flat portions 25, 27, 36, 38 of the heat transfer plates 1, 2. A plurality of cone covers 15 are formed for each of the band-shaped flat portions 25, 27, 36, 38. The cone covers 15 are formed at positions that divide the length of each of the band-shaped flat portions 25, 27, 36, 38 at equal intervals. The cone covers 15 are formed at positions closer to the heat exchange portion 5 than the widthwise center of each of the band-shaped flat portions 25, 27, 36, 38.

[0040] FIG. 9 is a partially enlarged cross-sectional view of the cone cover and the cone portion in the heat exchange element according to the first embodiment. FIG. 10 is a partially enlarged perspective cross-sectional view of the cone cover and the cone portion in the heat exchange element according to the first embodiment. The cone cover 15 is a recessed portion recessed from the bottom to the top. The cone cover 15 is convex on the back side of the recessed portion. The cone cover 15 is formed in a cone shape with a flat tip. The height of the cone cover 15 is set to a ratio of 1 or less to the gap distance between the heat exchange portion 5 and the cone cover 15. This ratio can prevent the material from becoming too thin and forming holes when the heat transfer plates 1 and 2 are formed by vacuum molding. The recess of the cone cover 15 is an elongated hole shape extending in the length direction of each of the band-shaped flat portions 25, 27, 36, and 38.

[0041] As shown in Figs. 4 and 5, the cones 16 are formed on the band-shaped flat portions 26, 28, 35, and 37 of the heat transfer plates 1 and 2. A plurality of cones 16 are formed on each of the band-shaped flat portions 26, 28, 35, and 37. The cones 16 are formed at positions that divide the length of each of the band-shaped flat portions 26, 28, 35, and 37 at equal intervals. The cones 16 are formed at positions closer to the heat exchange portion 5 than the widthwise center of each of the band-shaped flat portions 26, 28, 35, and 37. The height of the cones 16 is set to a ratio of 1 or less to the gap distance between the heat exchange portion 5 and the cones 16. This ratio can prevent holes from being formed in the material when the heat transfer plates 1 and 2 are formed by vacuum forming because the material becomes too thin.

[0042] 9 and 10, the cone 16 is a first convex portion that is convex upward. The cone 16 is formed in a conical shape with a curved tip.

[0043] When the heat transfer plates 1, 2 are stacked, the band-shaped plane portion 21 abuts against the lower band-shaped plane portion 31. The band-shaped plane portion 22 abuts against the upper band-shaped plane portion 32. The band-shaped plane portion 23 abuts against the lower band-shaped plane portion 33. The band-shaped plane portion 24 abuts against the upper band-shaped plane portion 34. The band-shaped plane portion 25 abuts against the lower band-shaped plane portion 35. The band-shaped plane portion 26 abuts against the upper band-shaped plane portion 36. The band-shaped plane portion 27 abuts against the lower band-shaped plane portion 37. The band-shaped plane portion 28 abuts against the upper band-shaped plane portion 38. As will be described in detail later, the abutting band-shaped flat portions 21, 22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 36, 37, and 38 become joining edges that are joined by ultrasonic welding.

[0044] The cone cover 15 and the cone 16 are formed at a position where they overlap each other in a plan view when the heat transfer plates 1 and 2 are stacked. When the heat transfer plates 1 and 2 are stacked as shown in Figures 9 and 10, the cone 16 fits into the recess of the cone cover 15. Note that the recess of the cone cover 15 may be recessed downward, and the cone 16 may be protruding downward.

[0045] Next, the manufacturing process of the heat exchange element will be described. FIG. 11 is a diagram showing a schematic configuration of a manufacturing apparatus for a heat exchange element according to the first embodiment. The manufacturing apparatus includes a receiving table 17 for placing the heat transfer plates 1 and 2. The receiving table 17 has a function of holding the heat transfer plates 1 and 2 by a method such as suction, and is provided with a positioning hole (not shown) at the same position as the protrusion 13. Furthermore, a guide pin 18 and a guide pin 19 are provided at the same position as the protrusion 13 on the upper part of the manufacturing apparatus. FIG. 12 is a perspective cross-sectional view showing a state in which the guide pin shown in FIG. 11 is fitted into the protrusion. The guide pin 18 can move up and down, and by moving downward, its tip is inserted into a recess on the back surface of the protrusion 13 as shown in FIG. 12. This is the same for the guide pin 19.

[0046] In the manufacturing process of the heat exchange element 50, stacking and fixing of the first heat transfer plate 1 and the second heat transfer plate 2 are repeated. Fig. 13 to Fig. 16 are diagrams showing the manufacturing process of the heat exchange element according to the first embodiment.

[0047] In the manufacturing process of the heat exchange element 50, as shown in FIG. 13, first, the first heat transfer plate 1, which is the first plate in the stack, is placed on the support 17. At this time, the protrusions 13 are aligned with the holes in the support 17 so that the protrusions 13 fit into the holes in the support 17 and are positioned accordingly.

[0048] Next, as shown in FIG. 14, the tip of the guide pin 18 is fitted into the recess on the back surface of the protrusion 13 of the second heat transfer plate 2 to be stacked next, and then the second heat transfer plate 2 is stacked as shown in FIG. 15. In this way, the abutting band-shaped flat parts 22, 24, 26, 28, 32, 34, 36, 38 are fixed to each other by ultrasonic welding while both the upper and lower heat transfer plates 1, 2 are positioned by the manufacturing device. Next, as shown in FIG. 16, the first heat transfer plate 1 to be stacked next is stacked while being positioned using the guide pin 19. In this way, the first heat transfer plate 1 and the second heat transfer plate 2 are alternately stacked and fixed to an arbitrary height. As can be seen from the explanation of the manufacturing process, the guide pin 18 is used to position the second heat transfer plate 2, and the guide pin 19 is used to position the first heat transfer plate 1.

[0049] Furthermore, the tips of the guide pins 18, 19 fit into the recesses on the back surface of the projections 13 to press the upper heat transfer plates 1, 2 against the lower heat transfer plates 1, 2, generating frictional resistance between the flat surface of the base 14 into which the projections 13 fit and the regions of the header parts 6a, 6b, 6c, 6d that come into contact with the flat surface of the base 14. This improves the reliability of ultrasonic welding and improves yield.

[0050] According to the heat exchange element 50 described above, the projections 13, the base 14, the cone cover 15, and the cone 16 formed on the heat transfer plates 1 and 2 make it difficult for the heat transfer plates 1 and 2 to be misaligned when stacked. Therefore, even when ultrasonic welding is performed to apply vibration to the heat transfer plates 1 and 2, the heat transfer plates 1 and 2 are not easily misaligned. In addition, simply stacking the heat transfer plates 1 and 2 makes the projections 13 fit into the recesses 14a of the base 14 and the cones 16 fit into the cone cover 15, so that positioning can be performed accurately and easily. In addition, if the projections 13 fit tightly into the recesses 14a of the base 14 and the cones 16 fit tightly into the cone cover 15, it is possible to make it even more difficult for the heat transfer plates 1 and 2 to be misaligned. In addition, the heat transfer plates 1 and 2 shrink toward their centers after molding. Since the recess 14a has an elongated hole shape with the longitudinal direction toward the center of the heat transfer plates 1, 2 in a plan view, the protrusion 13 can easily fit into the recess 14a even if the position of the base 14 is displaced due to contraction toward the center of the heat transfer plates 1, 2. In addition, the abutment of the protrusion 13 with the recess 14a prevents the heat transfer plates 1, 2 from shifting relative to each other in a direction different from the direction toward the center of the heat transfer plates 1, 2, thereby improving positioning accuracy.

[0051] Furthermore, even though the protrusion 13 and the base 14 are within the area of ​​the header portions 6a, 6b, 6c, 6d, they are located close to the band-shaped flat portions 22, 24, 31, 33, and the cone cover 15 and the cone 16 are also located on the band-shaped flat portions 25, 26, 27, 28, 35, 36, 37, 38. Therefore, even if a force is applied to shift the heat transfer plates 1, 2 due to ultrasonic welding, the bending stress generated in the heat transfer plates 1, 2 is limited to a short distance, making it difficult for the heat transfer plates to bend.

[0052] In addition, since multiple protrusions 13, bases 14, cone covers 15, and cones 16 are formed for each of the band-shaped flat portions 21, 22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 36, 37, and 38, positional deviation is further prevented.

[0053] In addition, since the protrusions 13 have a tapered shape, the cone cover 15 is conical, and the cone 16 is conical, centering is facilitated when positioning the heat transfer plates 1, 2 relative to each other or the heat transfer plates and the manufacturing equipment, and the positioning of the heat transfer plates 1, 2 relative to each other can be easily performed.

[0054] In addition, by performing ultrasonic welding in an accurately positioned state, it is possible to prevent the welding area from extending into other areas and to prevent the occurrence of defective welding in some areas, thereby preventing clogging due to excessive welding and air leakage from the heat exchange element 50.

[0055] In addition, the pedestal 14 is arranged so that the longer of the two diagonals of the diamond is aligned with the air flow direction, and the top of the pedestal 14 abuts the adjacent heat transfer plates 1 and 2, so that the pedestal 14 is unlikely to obstruct the air flow. Furthermore, by providing a gap between the pedestal 14 and the band-shaped flat parts 22, 24, 31, and 33, the turbulence of the air flow around the pedestal 14 and the sides 1d, 1f, 2c, and 2e can be reduced compared to the case where no gap is provided, and the occurrence of pressure loss can be suppressed. Furthermore, by arranging the pedestal 14 linearly in the air flow direction, the turbulence of the air flow can be similarly reduced, and the occurrence of pressure loss can be suppressed. Furthermore, by arranging the pedestal 14 and the sides 1d, 1f, 2c, and 2e as close as possible to each other with a gap therebetween, the distance between the welding point and the pedestal 14 is shortened as much as possible, and positioning can be more effectively performed during welding.

[0056] In addition, since the pedestal 14 is provided on the header portion 6a, 6b, 6c, 6d, the width of the band-shaped flat portion 21, 22, 23, 24, 31, 32, 33, 34 can be narrower than when the pedestal 14 is provided on the band-shaped flat portion 21, 22, 23, 24, 31, 32, 33, 34. For the same size of heat transfer plates 1, 2, the narrower width of the band-shaped flat portion 21, 22, 23, 24, 31, 32, 33, 34 allows the header portion 6a, 6b, 6c, 6d to be wider. Although the pedestal 14 is provided in the flow path, the wider header portion 6a, 6b, 6c, 6d allows the pressure loss of the heat exchange element 50 to be lower than when the pedestal 14 is provided on the band-shaped flat portion 21, 22, 23, 24, 31, 32, 33, 34.

[0057] The configurations shown in the above embodiments are examples of the contents of the present disclosure. The configurations of the embodiments can be combined with other known technologies. Part of the configurations of the embodiments can be omitted or modified without departing from the gist of the present disclosure. [Explanation of symbols]

[0058] 1 first heat transfer plate, 1a, 1b, 1c, 1d, 1e, 1f side, 2 second heat transfer plate, 2a, 2b, 2c, 2d, 2e, 2f side, 3, 4 air passage, 5 heat exchange section, 6a first header section, 6b second header section, 6c third header section, 6d fourth header section, 8 rib, 13 protrusion, 14 base, 14a recess, 15 cone cover, 16 cone, 17 receiving base, 18, 19 guide pin, 21, 22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 36, 37, 38 band-shaped flat section, 41, 42, 43, 44, 51, 52, 53, 54 step, 50 heat exchange element, 61 A first inlet surface, 62 a second inlet surface, 71 a first outlet surface, and 72 a second outlet surface.

Claims

1. A heat exchange element formed by stacking a plurality of heat transfer plates, The heat transfer plate has a heat exchange section that exchanges heat by passing air passing on one side of the stacking direction of the heat transfer plates and air passing on the other side of the stacking direction in opposing directions, header sections provided on one side and the other side of the heat exchange section as viewed along the stacking direction, and a joint edge section provided along a side of the heat exchange section that does not contact the header section, The joint edges of the stacked heat transfer plates are in contact with each other and joined by ultrasonic welding, The joint edge portion is formed with a first protruding portion that is protruding along the stacking direction and a recessed portion into which the first protruding portion of the adjacent heat transfer plate is fitted, A heat exchange element characterized in that the header portion is formed with a base that is convex along the stacking direction and has a recess at its top, and a second convex portion that fits into the recess of the adjacent heat transfer plate.

2. 2. The heat exchange element according to claim 1, wherein a flat area is provided on a top of the base, and the flat area abuts against the adjacent heat transfer plate.

3. The heat transfer plate has a hexagonal shape when viewed along the stacking direction, the first protrusion and the base are provided along any one of the sides of the hexagonal shape, The heat exchange element according to claim 1 or 2, wherein a plurality of the first protrusions and the plurality of the pedestals are formed on a side along which the first protrusions and the pedestals extend.

4. The heat exchange element according to claim 3 , wherein the first protrusions and the bases are provided at positions that divide the length of the side along which the first protrusions and the bases are disposed at equal intervals.

5. A heat exchange element described in any one of claims 1 to 4, characterized in that the base is diamond-shaped when viewed along the stacking direction, and the longer of two diagonals is formed along the flow direction of air passing through the header portion.

6. The base of the second protrusion is circular, 6. The heat exchange element according to claim 1, wherein a ratio of a height of the second protrusion to a diameter at a base of the second protrusion is 1 or less.

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