Heat exchanger

Abstract

[Problem] To provide a heat exchanger which enables the detection of a bonding state in the same flow passage which cannot be detected in a laminated-type heat exchanger. [Solution] This heat exchanger is bonded by diffusion bonding, and a plurality of first metal plates and a plurality of second metal plates are alternately laminated therein. The plurality of first metal plates are provided with a first partition wall and a plurality of first protrusions. The plurality of second metal plates are provided with a second partition wall and a plurality of second protrusions. One of the plurality of first protrusions and one of the plurality of second protrusions alternately overlap in the lamination direction. In the one of the plurality of first protrusions and the one of the plurality of second protrusions, a first through-hole is formed in the first protrusion, and a second through-hole is formed in the second protrusion. The first through-hole is formed in the first partition wall of a portion where the first protrusion is provided, and the second through-hole is formed in the second partition wall of a portion where the second protrusion is provided. A first passage in which the first through-hole and the second through-hole are connected in the lamination direction is formed.

Description

heat exchanger

[0001] The present invention relates to a stacked heat exchanger.

[0002] There is a stacked heat exchanger in which multiple metal plates, each having a flow path formed therein, are stacked and bonded by diffusion bonding. The multiple metal plates are provided with protrusions that form the fluid flow paths. The protrusions not only form the flow paths but also function as columnar protrusions that prevent the flow paths in the metal plates from being crushed by pressure applied in the thickness direction of the metal plates during diffusion bonding (see, for example, Patent Document 1). Furthermore, the protrusions also function as pressure-resistant structures against the fluid pressure of the fluid flowing through the flow paths.

[0003] To achieve the above-mentioned function, the stacked metal plates must be reliably joined by diffusion bonding. For example, the outer peripheries of the metal plates in the stacking direction must be reliably joined by diffusion bonding, and the protrusions and the metal plates located above the protrusions must be reliably joined by diffusion bonding.

[0004] For this reason, in such heat exchangers, leak tests are conducted to check the bonding state between the metal plates integrated by diffusion bonding. Known leak test methods include helium leak tests using helium gas, such as the vacuum hood method and the vacuum vessel method (bell jar method). These leak tests can also be applied to stacked heat exchangers, in which high-temperature and low-temperature flow paths are alternately arranged, when a hole is formed in the partition wall separating the high-temperature and low-temperature flow paths.

[0005] Japanese Patent Application Laid-Open No. 2018-096581

[0006] The above detection method is applicable when the poorly bonded portion is exposed to the outside of the heat exchanger or when a hole occurs between partition walls stacked one above the other in the stacking direction. However, the above detection method cannot detect insufficient bonding between a protrusion formed inside the heat exchanger and the metal plate located above the protrusion.

[0007] This is because the protrusions are not exposed to the outside of the heat exchanger, and even if an attempt is made to detect a leak by blocking one of the inlet and outlet ports of the flow path and pressurizing or depressurizing the other inlet and outlet port, no leak will occur because the joint surface between the protrusion and the partition wall above it and other areas form the same flow path through which the same fluid flows.

[0008] In view of the above circumstances, an object of the present invention is to provide a heat exchanger that makes it possible to detect the state of bonding within the same flow path when a leak test is used, which cannot be detected in a stacked heat exchanger.

[0009] To achieve the above object, one aspect of the present invention provides a heat exchanger including a laminated block body formed by stacking and bonding multiple metal plates by diffusion bonding. The laminated block body includes multiple first metal plates and multiple second metal plates, and the multiple first metal plates and the multiple second metal plates are alternately stacked in the laminated block body. Each of the multiple first metal plates is provided with a first partition wall and multiple first protrusions protruding from the first partition wall. Each of the multiple second metal plates is provided with a second partition wall and multiple second protrusions protruding from the second partition wall. Any of the multiple first protrusions and any of the multiple second protrusions alternately overlap in the stacking direction of the laminated block body. In any of the multiple first protrusions and any of the multiple second protrusions alternately stacked in the laminated block body, the first protrusion has a first through hole formed therethrough in the stacking direction, and the second protrusion has a second through hole formed therethrough in the stacking direction. The first through-hole is formed in the first partition wall at a portion where any of the plurality of first protrusions is provided, and the second through-hole is formed in the second partition wall at a portion where any of the plurality of second protrusions is provided. In the stacked block main body, a first passage is formed in which the first through-holes and the second through-holes are alternately connected in the stacking direction.

[0010] According to such a heat exchanger, when a leak test is performed, it is possible to detect the state of bonding within the same flow path, which cannot be detected in a stacked type heat exchanger.

[0011] The heat exchanger may further include a ceiling panel and a floor panel that sandwich the stacked block body in the stacking direction and are joined to the stacked block body by diffusion bonding, and at least one of the ceiling panel and the floor panel may have a second passage formed therein that penetrates in the stacking direction and is connected to the first passage.

[0012] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0013] In the heat exchanger, each of the plurality of first metal plates may have a first region in which the area per unit area occupied by the first protrusions is relatively large, and a second region in which the area per unit area occupied by the first protrusions is relatively small, and the first through hole may be formed in the first protrusion arranged in the second region.

[0014] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0015] In the heat exchanger, each of the plurality of second metal plates may have a third region in which the area per unit area occupied by the second protrusions is relatively large, and a fourth region in which the area per unit area occupied by the second protrusions is relatively small, and the second through hole may be formed in the second protrusion arranged in the fourth region.

[0016] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0017] In the heat exchanger, the first metal plate may have a first recess in which the first projection is disposed, and a first outer periphery surrounding the first recess.

[0018] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0019] In the heat exchanger, the second metal plate may have a second recess in which the second protrusion is disposed, and a second outer circumferential portion surrounding the second recess.

[0020] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0021] In the heat exchanger, each of the plurality of first metal plates has a first flow path formed between the plurality of first protrusions and a first inlet / outlet header communicating with the first flow path, and the plurality of first protrusions may include a first protrusion portion arranged along the first inlet / outlet header, and the first through hole may be formed in the first protrusion portion.

[0022] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0023] In the heat exchanger, each of the plurality of second metal plates has a second flow path formed between the plurality of second protrusions and a second inlet / outlet header communicating with the second flow path, and the plurality of second protrusions may include a second protrusion portion arranged along the second inlet / outlet header, and the second through hole may be formed in the second protrusion portion.

[0024] According to such a heat exchanger, when a leak test is performed, the state of bonding within the same flow path can be detected more reliably, which cannot be detected in a stacked type heat exchanger.

[0025] As described above, according to the present invention, a heat exchanger is provided that makes it possible to detect the state of bonding within the same flow path when a leak test is used, which cannot be detected in a stacked heat exchanger.

[0026] 1 is a schematic perspective view showing a heat exchanger of the present embodiment; FIG. 2 is a schematic perspective view showing a metal plate forming a laminated block main body before diffusion bonding; FIG. 3 is a schematic perspective view showing a metal plate forming a ceiling panel before diffusion bonding, and FIG. 4 is a schematic perspective view showing a metal plate forming a floor panel before diffusion bonding; FIG. 4 is a schematic cross-sectional view showing an example of a cross section of a heat exchanger formed after diffusion bonding; FIG. 5 is a schematic cross-sectional view showing an example of an operation of the present embodiment; FIG. 6 is a schematic plan view of a metal plate according to a first modified example of a laminated block main body; FIG. 7 is a schematic plan view of a metal plate according to a first modified example of a ceiling panel; FIG. 8 is a schematic plan view of a metal plate according to a first modified example of a floor panel; FIG. 9 is a schematic plan view of a metal plate according to a second modified example of a laminated block main body; FIG. 10 is a schematic plan view of a metal plate according to a second modified example of a ceiling panel; FIG. 11 is a schematic plan view of a metal plate according to a second modified example of a floor panel; and FIG. 12 is a schematic plan view of a metal plate according to a third modified example of a laminated block main body. Figure (a) is a schematic plan view of a metal plate according to a third modified example of the ceiling board. Figure (b) is a schematic plan view of a metal plate according to a third modified example of the floor board. Figure (a) is a schematic plan view of a metal plate according to a fourth modified example of the laminated block body. Figure (a) is a schematic plan view of a metal plate according to a fourth modified example of the ceiling board. Figure (b) is a schematic plan view of a metal plate according to the fourth modified example of the floor board.

[0027] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. XYZ axis coordinates may be introduced in each drawing. Furthermore, the same components or components having the same functions may be assigned the same reference numerals, and after describing the components, the description may be omitted as appropriate. Furthermore, the form of each component shown below is an example, and is not limited to this example.

[0028] Fig. 1 is a schematic perspective view showing a heat exchanger according to the present embodiment. The heat exchanger 1 shown in Fig. 1 is a stacked type heat exchanger and includes a stacked block body 2, a ceiling panel 3, and a floor panel 4.

[0029] The laminated block body 2 is sandwiched between the ceiling board 3 and the floor board 4 in the stacking direction. The laminated block body 2 includes a plurality of metal plates 21 (first metal plates) and a plurality of metal plates 22 (second metal plates). The laminated block body 2 is a block body in which the plurality of metal plates 21 and the plurality of metal plates 22 are alternately stacked and joined by diffusion bonding. Examples of diffusion bonding include solid-state bonding, hot pressure welding, and cold pressure welding. Because high-temperature fluid and low-temperature fluid exchange heat in the laminated block body 2, the metal plates 21 and 22 may also be referred to as heat transfer plates.

[0030] The ceiling panel 3 is a block body formed by stacking multiple metal plates 30 and bonding them together by diffusion bonding. The floor panel 4 is a block body formed by stacking multiple metal plates 40 and bonding them together by diffusion bonding. The ceiling panel 3 and the laminated block main body 2 are bonded together by diffusion bonding. The floor panel 4 and the laminated block main body 2 are bonded together by diffusion bonding. The ceiling panel 3 may be formed from a single metal plate having the same thickness as the thickness of the multiple stacked metal plates 30, and the floor panel 4 may be formed from a single metal plate having the same thickness as the thickness of the multiple stacked metal plates 40.

[0031] The heat exchanger 1 has an upper surface 1u formed on the ceiling panel 3 side, a lower surface 1d formed on the floor panel 4 side, and a side surface 1w connected to the upper surface 1u and the lower surface 1d. An inlet / outlet pipe 53, an inlet / outlet pipe 54, an inlet / outlet pipe 55, and an inlet / outlet pipe 56 are provided on the upper surface 1u. For example, when the heat exchanger 1 is used as a condenser, the inlet / outlet pipe 53 serves as an inlet pipe for a low-temperature fluid (e.g., water), and the inlet / outlet pipe 54 serves as an outlet pipe for the low-temperature fluid. The inlet / outlet pipe 55 serves as an outlet pipe for a high-temperature fluid (e.g., a refrigerant), and the inlet / outlet pipe 56 serves as an inlet pipe for the high-temperature fluid.

[0032] Headers 23, 24, 25, and 26 are formed at the four corners of the heat exchanger 1, penetrating the ceiling panel 3 and the laminated block main body 2 in the stacking direction. Header 23 communicates with an inlet / outlet pipe 53. Header 24 communicates with an inlet / outlet pipe 54. Header 25 communicates with an inlet / outlet pipe 55. Header 26 communicates with an inlet / outlet pipe 56. Header 25 and 26 are connected to a flow path (described later) provided in the metal plate 21. Header 23 and 24 are connected to a flow path (described later) provided in the metal plate 22. A plurality of passages 60 are provided on the upper surface 1u of the heat exchanger 1, extending in the stacking direction from the upper surface 1u to the lower surface 1d. Details of the passages 60 will be described later.

[0033] In the drawings of this embodiment, solid lines are drawn at the boundaries between the metal plates stacked in the stacking direction, but these solid lines may disappear without being visible in the diffusion-bonded heat exchanger 1. The Z-axis direction shown in the drawings corresponds to the stacking direction of the heat exchanger 1, the X-axis direction is approximately perpendicular to the Z-axis direction and corresponds to the direction from the inlet / outlet pipe 55 toward the inlet / outlet pipe 53, and the Y-axis direction is approximately perpendicular to the Z-axis direction and the X-axis direction and corresponds to the direction from the inlet / outlet pipe 55 toward the inlet / outlet pipe 54.

[0034] The metal plates 21, 22, 30, and 40 have high thermal conductivity and are made of the same material, such as aluminum, stainless steel, copper, an aluminum alloy, titanium, or a magnesium alloy.

[0035] 2(a) and 2(b) are schematic perspective views showing the metal plates forming the laminated block body before diffusion bonding, where Fig. 2(a) shows metal plate 21 and Fig. 2(b) shows metal plate 22.

[0036] As shown in FIG. 2A , the metal plate 21 has a rectangular planar shape, and is provided with a partition wall 211 (first partition wall), a plurality of protrusions 212 (first protrusions) protruding from the partition wall 211, and an outer periphery (first side wall portion) 213 surrounding the partition wall 211. The protrusions 212 have, for example, a circular shape when viewed from above. In the metal plate 21, there is a step between the partition wall 211 and the outer periphery 213, and the thickness of the partition wall 211 is formed thinner than the thickness of the outer periphery 213. In other words, a recess 216 is formed in the metal plate 21 by the partition wall 211 and the outer periphery 213. The recess 216 is surrounded by the outer periphery 213.

[0037] By providing the plurality of protrusions 212 on the partition wall 211, each of the spaces between the plurality of protrusions 212 on the partition wall 211 (the spaces between adjacent protrusions 212 in the XY plane) becomes a flow path 215 in the metal plate 21. In other words, the flow path 215 is formed in the recess 216. The flow path 215 is formed by, for example, half-etching. The partition wall 211 and the plurality of protrusions 212 are provided on, for example, each of the plurality of metal plates 21 included in the laminated block main body 2.

[0038] A through hole 231 (first opening), a through hole 241 (second opening), a through hole 251 (third opening), and a through hole 261 (fourth opening) are provided at the four corners of the metal plate 21 ( FIG. 2( a) ). Each of the through hole 251 and the through hole 261 functions as an inlet / outlet header communicating with the flow path 215. Furthermore, in the metal plate 21, a seal portion 2310 is provided that is continuous from the outer circumferential portion 213 on the flow path 215 side of the through hole 231 so as to surround the through hole 231. The seal portion 2310 is provided between the through hole 231 and the flow path 215, thereby separating the through hole 231 from the flow path 215. Furthermore, in the metal plate 21, a seal portion 2410 is provided that is continuous from the outer circumferential portion 213 on the flow path 215 side of the through hole 241 so as to surround the through hole 241. A seal portion 2410 is provided between the through-hole 241 and the flow path 215 to separate the through-hole 241 from the flow path 215 .

[0039] 2A, in the metal plate 21, a through hole 2121 (first through hole) penetrating in the stacking direction is formed in any one of the plurality of protrusions 212. The through hole 2121 is also formed in the partition wall 211 at a portion where any one of the plurality of protrusions 212 is provided. In other words, the through hole 2121 penetrates the metal plate 21 in the stacking direction.

[0040] As shown in FIG. 2( b ), the metal plate 22 has a rectangular planar shape, and is provided with a partition wall 221 (second partition wall), a plurality of protrusions 222 (second protrusions) protruding from the partition wall 221, and an outer periphery (second side wall portion) 223 surrounding the partition wall 221. When viewed from above, the protrusions 222 have, for example, a circular shape. In the metal plate 22, there is a step between the partition wall 221 and the outer periphery 223, and the thickness of the partition wall 221 is thinner than the thickness of the outer periphery 223. In other words, a recess 226 is formed in the metal plate 22 by the partition wall 221 and the outer periphery 223. The recess 226 is surrounded by the outer periphery 223.

[0041] By providing the plurality of protrusions 222 on the partition wall 221, each of the spaces between the plurality of protrusions 222 on the partition wall 221 (the spaces between adjacent protrusions 222 in the XY plane) becomes a flow path 225 of the metal plate 22. In other words, the flow path 225 is formed in the recess 226. The flow path 225 is formed by, for example, half-etching. The partition wall 221 and the plurality of protrusions 222 are provided on, for example, each of the plurality of metal plates 22 included in the laminated block main body 2.

[0042] A through hole 232 (a fifth opening), a through hole 242 (a sixth opening), a through hole 252 (a seventh opening), and a through hole 262 (an eighth opening) are provided at the four corners of the metal plate 22 (FIG. 2( b)). Each of the through holes 232 and 242 functions as an inlet / outlet header communicating with the flow path 225. In the metal plate 22, a seal portion 2520 is provided that is continuous from the outer circumferential portion 223 on the flow path 225 side of the through hole 252 so as to surround the through hole 252. The seal portion 2520 is provided between the through hole 252 and the flow path 225, thereby separating the through hole 252 from the flow path 225. In addition, in the metal plate 22, a seal portion 2620 is provided that is continuous from the outer circumferential portion 223 on the flow path 225 side of the through hole 262 so as to surround the through hole 262. A seal portion 2620 is provided between the through-hole 262 and the flow path 225 to separate the through-hole 262 from the flow path 225 .

[0043] 2B, in the metal plate 22, a through hole 2221 (second through hole) penetrating in the stacking direction is formed in any one of the plurality of protrusions 222. The through hole 2221 is also formed in the partition wall 221 at a portion where any one of the plurality of protrusions 222 is provided. In other words, the through hole 2221 penetrates the metal plate 21 in the stacking direction.

[0044] For example, when the heat exchanger 1 is used as a condenser, in the metal plate 21, the through hole 261 serves as an inlet for the high-temperature fluid and the through hole 251 serves as an outlet for the high-temperature fluid, and in the metal plate 22, the through hole 232 serves as an inlet for the low-temperature fluid and the through hole 242 serves as an outlet for the low-temperature fluid.

[0045] By alternately stacking a plurality of metal plates 21 and a plurality of metal plates 22 in the stacking direction, the through holes 231 provided in the metal plates 21 and the through holes 232 provided in the metal plates 22 are connected in the stacking direction to form the headers 23 in the stacked block main body 2. Furthermore, the through holes 241 provided in the metal plates 21 and the through holes 242 provided in the metal plates 22 are connected in the stacking direction to form the headers 24 in the stacked block main body 2. Furthermore, the through holes 251 provided in the metal plates 21 and the through holes 252 provided in the metal plates 22 are connected in the stacking direction to form the headers 25 in the stacked block main body 2. Furthermore, the through holes 261 provided in the metal plates 21 and the through holes 262 provided in the metal plates 22 are connected in the stacking direction to form the headers 26 in the stacked block main body 2.

[0046] FIG. 3(a) is a schematic perspective view showing a metal plate forming a ceiling panel before diffusion bonding, and FIG. 3(b) is a schematic perspective view showing a metal plate forming a floor panel before diffusion bonding.

[0047] As shown in Figure 3 (a), the metal plate 30 has a rectangular planar shape and is provided with a plurality of through holes 31 corresponding to the positions of the through holes (first through holes and second through holes) formed in the protrusions provided on the metal plate 21 or the metal plate 22.

[0048] The metal plate 30 has through holes 331, 341, 351, and 361 formed at its four corners. By stacking a plurality of metal plates 30, the through holes 331 formed in the metal plates 30 are connected in the stacking direction to form the header 23 of the ceiling plate 3. The through holes 341 formed in the metal plates 30 are connected in the stacking direction to form the header 24 of the ceiling plate 3. The through holes 351 formed in the metal plates 30 are connected in the stacking direction to form the header 25 of the ceiling plate 3. The through holes 361 formed in the metal plates 30 are connected in the stacking direction to form the header 26 of the ceiling plate 3. For example, when the heat exchanger 1 is used as a condenser, the through hole 331 serves as an inlet for a low-temperature fluid, the through hole 341 serves as an outlet for a low-temperature fluid, the through hole 361 serves as an inlet for a high-temperature fluid, and the through hole 351 serves as an outlet for a high-temperature fluid. Here, for example, the low-temperature fluid is water, and the high-temperature fluid is a refrigerant that undergoes a phase change between gas and liquid.

[0049] As shown in Figure 3 (b), the metal plate 40 has a rectangular planar shape and is provided with a plurality of through holes 41 corresponding to the positions of the through holes (first through holes and second through holes) formed in the protrusions provided on the metal plate 21 or the metal plate 22.

[0050] In the present embodiment, when a plurality of metal plates 21 ( FIG. 2( a) ) and a plurality of metal plates 22 ( FIG. 2( b) ) are alternately stacked in the stacking direction, any of the protrusions 212 provided on the metal plates 21 and any of the protrusions 222 provided on the metal plates 22 alternately overlap in the stacking direction of the laminated block body 2. For example, of the plurality of protrusions 212 provided on each metal plate 21, the protrusions 212 other than the protrusions 212 arranged around the through holes 251 and 261 and, of the plurality of protrusions 222 provided on each metal plate 22, the protrusions 222 arranged along the through holes 232 and 243 alternately overlap in the stacking direction.

[0051] Fig. 4 is a schematic cross-sectional view showing an example of a cross section of a heat exchanger formed after diffusion bonding, showing cross sections corresponding to positions along line A1-A2 in Fig. 2(a), line B1-B2 in Fig. 2(b), line C1-C2 in Fig. 3(a), and line D1-D2 in Fig. 3(b).

[0052] As described above, a plurality of metal plates 21 and a plurality of metal plates 22 are alternately stacked and joined by diffusion bonding to form the laminated block body 2. A plurality of metal plates 30 are stacked and joined by diffusion bonding to form the ceiling board 3. A plurality of metal plates 40 are stacked and joined by diffusion bonding to form the floor board 4. The ceiling board 3 and the laminated block body 2 are joined by diffusion bonding, and the floor board 4 and the laminated block body 2 are joined by diffusion bonding.

[0053] Furthermore, the upper surfaces of the protrusions 212 provided on the metal plate 21 are joined to the partition walls 221 of the metal plate 22 arranged on the metal plate 21, thereby forming flow paths 215 in the metal plate 21. The upper surfaces of the protrusions 222 provided on the metal plate 22 are joined to the partition walls 211 of the metal plate 21 arranged on the metal plate 22, or are joined to the metal plate 30, thereby forming flow paths 225 in the metal plate 22.

[0054] Here, when the protrusions 212 provided on the metal plate 21 and the protrusions 222 provided on the metal plate 22 are alternately stacked, the through holes 2121 provided in the protrusions 212 and the through holes 2221 provided in the protrusions 222 are alternately connected in the stacking direction to form passages 62 (first passages). In other words, the passages 62 that penetrate the stacking direction are formed in the stacked block main body 2.

[0055] Furthermore, when multiple metal plates 40 are stacked, the through holes 41 provided in the metal plates 40 communicate in the stacking direction to form a passage 64. That is, the floor board 4 is formed with a passage 64 that penetrates in the stacking direction. Furthermore, when multiple metal plates 30 are stacked, the through holes 31 provided in the metal plates 30 communicate in the stacking direction to form a passage 63. That is, the ceiling board 3 is formed with a passage 63 that penetrates in the stacking direction. The passage 63 and the passage 64 are collectively referred to as a second passage.

[0056] The passages 62 and 64, and the passages 62 and 63, are connected to each other in the stacking direction to form a passage 60 that penetrates the heat exchanger 1 from the lower surface 1d to the upper surface 1u. The passage 60 is open to the outside of the heat exchanger 1. Note that either the passage 63 provided in the ceiling panel 3 or the passage 64 provided in the floor panel 4 may be omitted. It is sufficient that the passages 62 and 64, or the passages 62 and 63, are connected to each other in the stacking direction.

[0057] Fig. 5 is a schematic cross-sectional view showing an example of the operation of this embodiment. Fig. 5 shows a state in which there is a diffusion bonding defect between one of the upper surfaces of multiple protrusions 212 provided on the metal plate 21 and the partition wall 221 of the metal plate 22 arranged above that protrusion 212. For example, in Fig. 5, the bonding defect location is surrounded by a dashed line 100. In this embodiment, the passage 60 of the heat exchanger 1 is used as a bonding defect detection passage.

[0058] For example, if He (helium) gas flows into passage 60 of heat exchanger 1 as a gas for detecting poor bonding, unless protrusion 212 on metal plate 21 and partition wall 221 of metal plate 22 placed above protrusion 212 are joined by diffusion bonding to connect passage 60 and flow path 215, He gas will not flow from passage 60 into flow path 215 even if inlet / outlet pipe 55 is blocked and a vacuum is drawn from inlet / outlet pipe 56.

[0059] 5 , if a poor joint 100 exists between a protrusion 212 provided on the metal plate 21 and a partition wall 221 disposed on the protrusion 212, connecting the passage 60 and the flow path 215, for example, by closing the inlet / outlet pipe 55 and drawing a vacuum through the inlet / outlet pipe 56 to evacuate the flow path 215 communicating with the inlet / outlet pipe 56 and the through-hole 261, He gas will flow from the passage 60 through the poor joint 100 into the flow path 215. The He gas that has flowed into the flow path 215 will flow to the inlet / outlet pipe 56 via the through-hole 261 in the metal plate 21.

[0060] In other words, when He gas is introduced into the passage 60 of the heat exchanger 1, if He gas is detected flowing out from the vacuumed inlet / outlet pipe 56, it can be determined that there is a poor bond between the protrusion and the metal plate partition wall placed above the protrusion in the heat exchanger 1.

[0061] In this way, with heat exchanger 1, it is possible to detect poor bonding at the joint of the protrusion where the bonding is poor (the joint between the protrusion and the metal plate partition placed on the protrusion) even in a heat exchanger in which the flow path other than this joint is a flow path through which the same fluid flows.

[0062] (First Modification) The through-holes formed in the protrusions may be provided in specific protrusions among the plurality of protrusions.

[0063] For example, when the heat exchanger 1 is in use, the flow path 215 (recess 216) formed by sandwiching the metal plate 21 between the metal plate 22 above it, or the flow path 225 (recess 226) formed by sandwiching the metal plate 22 between the metal plate 21 above it, is subjected to pressure by the fluid that causes it to expand in the vertical direction.

[0064] In this case, it is particularly important that the joints between the partition walls of the multiple protrusions, particularly those sparsely arranged on the partition walls or those with a small occupancy area relative to the partition walls (i.e., those with a small cross-sectional area when cut in a plane parallel to the X-Y plane), and the partition walls above them, maintain a strong bond even when pressure is applied by the fluid to cause them to expand vertically. These protrusions are subject to a larger pressure (pressure to expand vertically) per protrusion than those densely arranged on the partition walls or those with a large occupancy area relative to the partition walls (i.e., those with a large cross-sectional area when cut in a plane parallel to the X-Y plane). If the joint is insufficient, the pressure can easily cause the joint to peel off, or the joint can peel off due to deterioration over time. If the joint peels off, the protrusions will no longer have the strength to hold the partition walls against the pressure, which may cause the flow path to expand vertically and deform the metal plate 21 or the metal plate 22.

[0065] In this way, the joints between the protrusions that are sparsely arranged on the partition wall or the protrusions that occupy a small area relative to the partition wall and the partition wall above them are required to have sufficient pressure resistance to prevent the joints from peeling off even when pressure that tends to spread them in the vertical direction is applied.

[0066] Figures 6(a) and (b) are schematic plan views of metal plates according to a first modified example of the laminated block main body. Figure 6(a) shows one metal plate 21 out of the plurality of metal plates 21. Figure 6(b) shows one metal plate 22 out of the plurality of metal plates 22. Figure 7(a) is a schematic plan view of a metal plate according to a first modified example of the ceiling board. Figure 7(b) is a schematic plan view of a metal plate according to the first modified example of the floor board.

[0067] 6A, when the metal plate 21 is viewed from above, the metal plate 21 has a first region (a region surrounded by dashed line 101 in the recess 216) in which the area occupied by the protrusions 212 per unit area of ​​the metal plate 21 (the area occupied per unit area means the area occupied per unit area of ​​the recess 216) is relatively large, and a second region (a region outside the region surrounded by dashed line 101 in the recess 216 and surrounded by dashed line 102) in which the area occupied by the protrusions 212 per unit area of ​​the metal plate 21 is relatively small. For example, the area surrounded by dashed line S1 and the area surrounded by dashed line S2 are assumed to be equal in area. It can be seen that the area occupied by the protrusions 212 in the region surrounded by dashed line S1 is larger than the area occupied by the protrusions 212 in the region surrounded by dashed line S2.

[0068] In the metal plate 21, the plurality of protrusions 212 arranged in the first region do not have through holes 2121, but the through holes 2121 are formed in one of the plurality of protrusions 212 arranged in the second region.

[0069] The plurality of protrusions 212 arranged in the second region are arranged near the outer periphery 213 or near the sealing portions 2310 and 2410, and occupy a relatively smaller area per unit area than the plurality of protrusions 212 arranged in the first region. As a result, a stronger pressure tends to spread in the vertical direction as described above is applied to each of the plurality of protrusions 212 arranged in the second region than to each of the plurality of protrusions 212 arranged in the first region. Therefore, it is necessary to detect whether any of the plurality of protrusions 212 arranged in the second region is sufficiently bonded to the metal plate 22 above it, prior to detecting the plurality of protrusions 212 arranged in the first region.

[0070] For example, any one of the plurality of protrusions 212 arranged in the second region may have a through hole 2121. This allows the bonding state between any one of the plurality of protrusions 212 arranged in the second region and the metal plate 22 thereon to be reliably detected by a leak test.

[0071] Furthermore, as shown in FIG. 6( b), when the metal plate 22 is viewed from above, the metal plate 22 has a third region (a region surrounded by dashed line 103 in the recess 226) in which the area occupied by the protrusion 222 per unit area of ​​the metal plate 22 is relatively large, and a fourth region (a region outside the region surrounded by dashed line 103 in the recess 226 and surrounded by dashed line 104) in which the area occupied by the protrusion 222 per unit area of ​​the metal plate 22 is relatively small.

[0072] In the metal plate 22, the plurality of protrusions 222 arranged in the third region do not have through holes 2221, but the through holes 2221 are formed in one of the plurality of protrusions 222 arranged in the fourth region.

[0073] The plurality of protrusions 222 arranged in the fourth region are arranged near the outer periphery 223, the through holes 232, 242, or the seal portions 2520, 2620, and occupy a relatively smaller area per unit area than the plurality of protrusions 222 arranged in the third region. As a result, a stronger pressure tends to spread in the vertical direction as described above is applied to each of the plurality of protrusions 222 arranged in the fourth region than to each of the plurality of protrusions 222 arranged in the third region. Therefore, it is necessary to detect whether any of the plurality of protrusions 222 arranged in the fourth region is sufficiently bonded to the metal plate 22 above it, prior to the detection of the plurality of protrusions 222 arranged in the third region.

[0074] For example, any one of the plurality of protrusions 222 arranged in the fourth region may have a through hole 2221. This allows the bonding state between any one of the plurality of protrusions 222 arranged in the fourth region and the metal plate 21 thereon to be reliably detected by a leak test.

[0075] In addition, depending on the metal plate 21 related to the first modified example and the metal plate 22 related to the first modified example, the arrangement of the through holes 31 provided in the metal plate 30 forming the ceiling board 3 is changed (Figure 7(a)), and the arrangement of the through holes 41 provided in the metal plate 40 forming the floor board 4 is changed (Figure 7(b)).

[0076] (Second Modification) Figures 8(a) and (b) are schematic plan views of metal plates according to a second modification of the stacked block main body. Figure 8(a) shows one metal plate 21 out of the plurality of metal plates 21. Figure 8(b) shows one metal plate 22 out of the plurality of metal plates 22. Figure 9(a) is a schematic plan view of a metal plate according to a second modification of the ceiling board. Figure 9(b) is a schematic plan view of a metal plate according to the second modification of the floor board.

[0077] In the metal plate 21, protrusions whose area when viewed from above (the area of ​​the protrusion in the X-Y plane) is relatively smaller than the other protrusions may be arranged in the recess 216. For example, as shown in FIG. 8( a), the area of ​​each of the plurality of protrusions 212a arranged in the region surrounded by the dashed line 105 is smaller than the area of ​​each of the plurality of protrusions 212 arranged in the region surrounded by the dashed line 106. In other words, the plurality of protrusions 212a arranged in the region surrounded by the dashed line 105 are arranged so that the area that the protrusions 212a occupy per unit area is relatively smaller than the area of ​​the plurality of protrusions 212 arranged in the region surrounded by the dashed line 106.

[0078] As a result, a stronger pressure to spread in the vertical direction as described above is applied to each of the plurality of protrusions 212a arranged in the region surrounded by dashed line 105 than to each of the plurality of protrusions 212 arranged in the region surrounded by dashed line 106. Therefore, it is necessary to detect whether any of the plurality of protrusions 212a arranged in the region surrounded by dashed line 105 is sufficiently bonded to the metal plate 22 above it, with priority given to detecting the plurality of protrusions 212 arranged in the region surrounded by dashed line 106.

[0079] For example, one of the plurality of protrusions 212a arranged in the region surrounded by the dashed line 105 is provided with a through-hole 2121. This allows the bonding state between one of the plurality of protrusions 212a arranged in the region surrounded by the dashed line 105 and the metal plate 22 thereon to be reliably detected by a leak test.

[0080] Furthermore, in the metal plate 22, protrusions whose area when viewed from above (the area of ​​the protrusion in the X-Y plane) is relatively smaller than the other protrusions may be arranged in the recess 226. For example, as shown in FIG. 8( b), the area of ​​each of the plurality of protrusions 222a arranged in the region surrounded by the dashed line 107 is smaller than the area of ​​each of the plurality of protrusions 222 arranged in the region surrounded by the dashed line 108. In other words, the plurality of protrusions 222a arranged in the region surrounded by the dashed line 107 are arranged so that the area that the protrusions 222a occupy per unit area is relatively smaller than the area of ​​the plurality of protrusions 222 arranged in the region surrounded by the dashed line 108.

[0081] As a result, a stronger pressure to spread in the vertical direction as described above is applied to each of the plurality of protrusions 222a arranged in the region surrounded by dashed line 107 than to each of the plurality of protrusions 222 arranged in the region surrounded by dashed line 108. Therefore, it is necessary to detect whether any of the plurality of protrusions 222a arranged in the region surrounded by dashed line 107 is sufficiently bonded to the metal plate 21 above it, with priority given to detecting the plurality of protrusions 222 arranged in the region surrounded by dashed line 108.

[0082] For example, any one of the plurality of protrusions 222a arranged in the region surrounded by the dashed line 106 is provided with a through-hole 2221. This makes it possible to reliably detect the bonding state between any one of the plurality of protrusions 222a arranged in the region surrounded by the dashed line 106 and the metal plate 21 thereon by a leak test.

[0083] In addition, depending on the metal plate 21 relating to the second modified example and the metal plate 22 relating to the second modified example, the arrangement of the through holes 31 provided in the metal plate 30 forming the ceiling board 3 is changed (Figure 9(a)), and the arrangement of the through holes 41 provided in the metal plate 40 forming the floor board 4 is changed (Figure 9(b)).

[0084] (Third Modification) Figures 10(a) and (b) are schematic plan views of metal plates according to a third modification of the stacked block main body. Figure 10(a) shows one metal plate 21 out of the plurality of metal plates 21. Figure 10(b) shows one metal plate 22 out of the plurality of metal plates 22. Figure 11(a) is a schematic plan view of a metal plate according to a third modification of the ceiling board. Figure 11(b) is a schematic plan view of a metal plate according to the third modification of the floor board.

[0085] 10( a), in the metal plate 21, the multiple protrusions 212 include a protrusion 212b arranged along the through hole 251 and multiple protrusions 212c arranged along the through hole 261. The outer periphery of the protrusion 212b is cut out to fit the inner periphery of the through hole 251, and when viewed from above, the planar shape of the protrusion 212b is a shape in which a part of a circle is recessed in an arc. The outer periphery of each of the multiple protrusions 212c is cut out to fit the inner periphery of the through hole 261, and when viewed from above, the planar shape of each of the multiple protrusions 212c is a shape in which a part of a circle is recessed in an arc.

[0086] In the metal plate 21, a through hole 2121 is formed in the protrusion 212c. Also, the through hole 2121 is formed in one of the plurality of protrusions 212c. Also, a through hole 2221 is provided in the sealing portion 2520 of the metal plate 22 shown in Fig. 10(b) so as to overlap in the stacking direction with the through hole 2121 provided in the protrusion 212b. Also, a through hole 2221 is provided in the sealing portion 2620 of the metal plate 22 so as to overlap in the stacking direction with the through hole 2121 provided in the protrusion 212c.

[0087] The area of ​​each of the protrusions 212b or the plurality of protrusions 212c is smaller than the area of ​​each of the plurality of protrusions 212 arranged in the region surrounded by the dashed line 101. In other words, each of the protrusions 212b or the plurality of protrusions 212c is arranged so that the area that the protrusion occupies per unit area is relatively smaller than the area of ​​the plurality of protrusions 212 arranged in the region surrounded by the dashed line 101.

[0088] As a result, the pressure tending to expand in the vertical direction as described above is stronger on each of the protrusions 212b or the plurality of protrusions 212c than on each of the plurality of protrusions 212 arranged in the area surrounded by the dashed line 101. Therefore, it is necessary to detect whether the protrusion 212b or the plurality of protrusions 212c is sufficiently bonded to the metal plate 22 above it with priority over the plurality of protrusions 212 arranged in the area surrounded by the dashed line 101.

[0089] Therefore, either the protrusion 212b or the plurality of protrusions 212c is provided with the through-hole 2121. This makes it possible to reliably detect the bonding state between the protrusion 212b or the plurality of protrusions 212c and the metal plate 22 thereon by a leak test.

[0090] 10(b), in the metal plate 22, the plurality of protrusions 222 include a plurality of protrusions 222b arranged along the through hole 232 and a plurality of protrusions 222c arranged along the through hole 242. The outer periphery of each of the plurality of protrusions 222b is cut out to fit the inner periphery of the through hole 232, and when viewed from above, each has a planar shape in which a portion of a circle is recessed in an arc. The outer periphery of each of the plurality of protrusions 222c is cut out to fit the inner periphery of the through hole 242, and when viewed from above, each has a planar shape in which a portion of a circle is recessed in an arc.

[0091] In the metal plate 22, a through hole 2221 is formed in one of the plurality of protrusions 222c. Also, a through hole 2221 is formed in one of the plurality of protrusions 222c. Also, a through hole 2121 is provided in the seal portion 2310 of the metal plate 21 shown in Fig. 10(a) so as to overlap with the through hole 2221 provided in the protrusion 222b in the stacking direction. Also, a through hole 2121 is provided in the seal portion 2410 of the metal plate 21 so as to overlap with the through hole 2221 provided in the protrusion 222c in the stacking direction.

[0092] The area of ​​each of the plurality of protrusions 222b or each of the plurality of protrusions 222c is smaller than the area of ​​each of the plurality of protrusions 222 arranged in the region surrounded by dashed line 103. In other words, each of the plurality of protrusions 222b or each of the plurality of protrusions 222c is arranged so that the area that the protrusion occupies per unit area is relatively smaller than the area of ​​the plurality of protrusions 212 arranged in the region surrounded by dashed line 103.

[0093] As a result, a stronger pressure to spread in the vertical direction as described above is applied to each of the plurality of protrusions 222b or each of the plurality of protrusions 222c than to each of the plurality of protrusions 222 arranged in the area surrounded by dashed line 103. Therefore, it is necessary to detect whether any of the plurality of protrusions 222b or any of the plurality of protrusions 222c is sufficiently bonded to the metal plate 21 above it with priority over the plurality of protrusions 222 arranged in the area surrounded by dashed line 103.

[0094] Therefore, either one of the plurality of protrusions 222b or one of the plurality of protrusions 222c is provided with the through-hole 2221. This makes it possible to reliably detect the bonding state between either one of the plurality of protrusions 222b or one of the plurality of protrusions 222c and the metal plate 21 thereon by a leak test.

[0095] In addition, depending on the metal plate 21 relating to the third modified example and the metal plate 22 relating to the third modified example, the arrangement of the through holes 31 provided in the metal plate 30 forming the ceiling board 3 is changed (Figure 11 (a)), and the arrangement of the through holes 41 provided in the metal plate 40 forming the floor board 4 is changed (Figure 11 (b)).

[0096] In this embodiment, protrusion 212b or protrusion 212c is collectively referred to as a first protrusion portion. Furthermore, through-hole 251 or through-hole 261 is collectively referred to as a first entrance / exit header. Furthermore, protrusion 222b or protrusion 222c is collectively referred to as a second protrusion portion. Furthermore, through-hole 232 or through-hole 242 is collectively referred to as a second entrance / exit header.

[0097] (Fourth Modification) A pressure jig is used when the plurality of metal plates 21 and the plurality of metal plates 22 are alternately stacked and diffusion bonded together. For example, a stack is formed by alternately stacking the plurality of metal plates 21 and the plurality of metal plates 22, and the stack is sandwiched between a pair of pressure blocks from above and below, and diffusion bonding is performed while applying pressure to the stack in the vertical direction by the pair of pressure blocks.

[0098] When the stack is pressed by the pair of pressure blocks, it is difficult to maintain a perfectly parallel state between the pair of pressure blocks, and the stack may deviate slightly from the parallel state. Therefore, the pressure applied during diffusion bonding may be weaker in the center of the stack than on the periphery. That is, the pressure applied to the protrusions disposed in the center of each of the plurality of metal plates 21 and the center of each of the plurality of metal plates 22 during diffusion bonding is weaker than that applied to the protrusions disposed in the periphery. Therefore, the bonding state between the protrusions disposed in the center and the partition wall above them may be insufficient compared to the bonding state between the protrusions disposed in the periphery and the partition wall above them. Therefore, it is necessary to prioritize whether the protrusions disposed in the center are sufficiently bonded to the partition wall above them.

[0099] Figures 12(a) and (b) are schematic plan views of metal plates according to a fourth modified example of the laminated block main body. Figure 12(a) shows one metal plate 21 out of the plurality of metal plates 21. Figure 12(b) shows one metal plate 22 out of the plurality of metal plates 22. Figure 13(a) is a schematic plan view of a metal plate according to a fourth modified example of the ceiling board. Figure 13(b) is a schematic plan view of a metal plate according to the fourth modified example of the floor board.

[0100] 12(a), in the metal plate 21, a through hole 2121 is formed in one of a plurality of protrusions 212 arranged in the central part of the metal plate 21 surrounded by the dashed line 109. This makes it possible to reliably detect the bonding state between one of the plurality of protrusions 212 arranged in the central part of the metal plate 21 surrounded by the dashed line 109 and the metal plate 22 above it by a leak test.

[0101] 12(b), in the metal plate 22, a through hole 2221 is formed in one of a plurality of protrusions 222 arranged in the central portion of the metal plate 22 surrounded by the dashed line 110. This makes it possible to reliably detect the bonding state between one of the plurality of protrusions 222 arranged in the central portion of the metal plate 22 surrounded by the dashed line 110 and the metal plate 21 above it by a leak test.

[0102] In addition, depending on the metal plate 21 relating to the fourth modified example and the metal plate 22 relating to the fourth modified example, the arrangement of the through holes 31 provided in the metal plate 30 forming the ceiling board 3 is changed (Figure 13(a)), and the arrangement of the through holes 41 provided in the metal plate 40 forming the floor board 4 is changed (Figure 13(b)).

[0103] Although the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to the above-described embodiments and various modifications can be made. Each embodiment is not limited to an independent form, and can be combined as far as technically possible.

[0104] DESCRIPTION OF SYMBOLS 1...Heat exchanger 1u...Upper surface 1d...Lower surface 1w...Side surface 2...Laminated block body 3...Ceiling plate 4...Floor plate 21...Metal plate (first metal plate) 22...Metal plate (second metal plate) 23, 24, 25, 26...Header 30, 40...Metal plate 31, 41, 231, 232, 241, 242, 251, 252, 261, 262, 331, 341, 351, 361...Through holes 53, 54, 55, 56...Inlet / outlet pipes 60...Passage 62...Passage (first passage) 63...Passage (second passage) 64...Passage (second passage) 100...Poor joint location 211...Partition wall (first partition wall) 212...Protrusion (first protrusion) 212a, 212b, 212c...Protrusion 213...Outer periphery (first outer periphery) 215...Flow path (first flow path) 216...Recess (first recess) 221...Partition (second partition) 222...Protrusion (second projection) 222a, 222b, 222c...Protrusions 223...Outer periphery (second outer periphery) 225...Flow path (second flow path) 226...Recess (second recess) 2121...Through hole (first through hole) 2221...Through hole (second through hole) 2310, 2410, 2520, 2620...Sealing portion

Claims

1. A heat exchanger including a laminated block body in which a plurality of metal plates are stacked and bonded by diffusion bonding, wherein the laminated block body includes a plurality of first metal plates and a plurality of second metal plates, the plurality of first metal plates and the plurality of second metal plates are alternately stacked in the laminated block body, each of the plurality of first metal plates is provided with a first partition wall and a plurality of first projections protruding from the first partition wall, each of the plurality of second metal plates is provided with a second partition wall and a plurality of second projections protruding from the second partition wall, any of the plurality of first projections and any of the plurality of second projections are alternately overlapped in a stacking direction of the laminated block body, and in any of the plurality of first projections and any of the plurality of second projections alternately overlapped in the laminated block body, the first projection has a first through hole formed therethrough in the stacking direction, and the second projection has a second through hole formed therethrough in the stacking direction, the first through hole is formed in the first partition wall at a portion where any of the plurality of first protrusions is provided, and the second through hole is formed in the second partition wall at a portion where any of the plurality of second protrusions is provided, and a first passage is formed in the stacking block main body in which the first through holes and the second through holes are alternately connected in the stacking direction.

2. A heat exchanger as described in claim 1, further comprising a ceiling plate and a floor plate which sandwich the laminated block body in the stacking direction and are joined to the laminated block body by diffusion bonding, and at least one of the ceiling plate and the floor plate has a second passage formed therein which penetrates in the stacking direction and is connected to the first passage.

3. A heat exchanger as described in claim 1 or 2, wherein each of the plurality of first metal plates has a first region in which the area per unit area occupied by the first protrusions is relatively large, and a second region in which the area per unit area occupied by the first protrusions is relatively small, and the first through holes are formed in the first protrusions arranged in the second region.

4. A heat exchanger as described in claim 1 or 2, wherein each of the plurality of second metal plates has a third region in which the area per unit area occupied by the second protrusions is relatively large, and a fourth region in which the area per unit area occupied by the second protrusions is relatively small, and the second through holes are formed in the second protrusions arranged in the fourth region.

5. A heat exchanger according to claim 1 or 2, wherein said first metal plate has a first recess in which said first protrusion is disposed, and a first outer periphery surrounding said first recess.

6. A heat exchanger as claimed in claim 1 or 2, wherein said second metal plate has a second recess in which said second protrusion is disposed, and a second outer peripheral portion surrounding said second recess.

7. A heat exchanger as described in claim 1 or 2, wherein each of the plurality of first metal plates has a first flow passage formed between the plurality of first protrusions and a first inlet / outlet header communicating with the first flow passage, the plurality of first protrusions include a first protrusion portion arranged along the first inlet / outlet header, and the first through hole is formed in the first protrusion portion.

8. A heat exchanger as described in claim 1 or 2, wherein each of the plurality of second metal plates has a second flow passage formed between the plurality of second protrusions and a second inlet / outlet header communicating with the second flow passage, the plurality of second protrusions include second protrusion portions arranged along the second inlet / outlet header, and the second through hole is formed in the second protrusion portion.

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