WO2021149139A1

WO2021149139A1 - Plate-type heat exchanger and heat transfer device

Info

Publication number: WO2021149139A1
Application number: PCT/JP2020/001889
Authority: WO
Inventors: 寿守務吉村; 亮輔安部; 佳峰永島; 匠白石; 発明孫; 進一内野; 憲成澤田
Original assignee: 三菱電機株式会社
Priority date: 2020-01-21
Filing date: 2020-01-21
Publication date: 2021-07-29
Also published as: JPWO2021149139A1; JP7292435B2

Abstract

This plate-type heat exchanger comprises a main body in which a plurality of heat transfer plates are stacked, and a first flow path through which a first fluid flows and a second flow path through which a second fluid flows are alternatively formed with the heat transfer plates serving as borders. The main body forms the first flow path between a first heat transfer plate and a second heat transfer plate, and has an inner fin in the first flow path. The first heat transfer plate has two plates and a plurality of brazed sections for connecting the two plates. A plurality of hollow sections and a communication path, for connecting hollow sections of the plurality of hollow sections to each other, are formed inside the first heat transfer plate. The inner fin has, in the flowing direction, a plurality of recess-and-protrusion pitches formed in an recessed and protruding manner. At least one or more of the recess-and-protrusion pitches have a first pitch that abuts the first heat transfer plate and the second heat transfer plate, and a second pitch that abuts the second heat transfer plate and is larger than the first pitch. When the inside of the main body is projected in the stacking direction, the plurality of hollow sections are formed in the region of the second pitch, and a discharge flow path, formed by the plurality of hollow sections and the communication path, is configured to communicate with the outside of the body.

Description

Plate heat exchanger and heat transfer device

The present invention relates to a plate-type heat exchanger and a heat transfer device in which a plurality of a pair of first heat transfer plates for circulating a first fluid inside and a pair of second heat transfer plates for passing a second fluid inside are stacked. It is a thing.

Conventionally, a plate-type heat exchanger having openings at four corners and having a plurality of heat transfer plates whose surfaces are formed to be uneven or corrugated is laminated, and the outer wall of the heat transfer plate and the periphery of the openings are brazed and joined. It is known (see, for example, Patent Document 1). In the plate heat exchanger of Patent Document 1, a first flow path through which the first fluid flows and a second flow path through which the second fluid flows are alternately formed. Further, in the plate heat exchanger of Patent Document 1, each of the openings at the four corners is connected to form a first header for allowing the first fluid to flow in and out of the first flow path, and the second flow path has a first header. On the other hand, a second header is formed to allow the second fluid to flow in and out. Each heat transfer plate is composed of a double wall in which two metal plates are superposed.

The plate-type heat exchanger of Patent Document 1 has a double-wall structure even if the heat transfer plate is damaged due to factors such as freezing and a crack should occur. Therefore, it is possible to prevent the refrigerant from leaking to the indoor side through both the first flow path and the second flow path. Further, the plate heat exchanger of Patent Document 1 detects the leaked fluid flowing out to the outside with a detection sensor and stops the device provided with the plate heat exchanger to prevent damage to the device. Can be done.

Japanese Unexamined Patent Publication No. 2014-66411

However, the damaged state of the plate heat exchanger is determined by error factors such as manufacturing conditions or environmental conditions. Therefore, it is difficult for all the plate-type heat exchangers produced to fulfill the function of preventing the leakage of the internal fluid in the long term, and in the plate-type heat exchanger, the first heat transfer plate and the second heat transfer plate are used. There is a possibility that the area in contact with the plate will be damaged. When the area where the first heat transfer plate and the second heat transfer plate are in contact with each other is damaged, both the first heat transfer plate and the second heat transfer plate are damaged, so that the first fluid and the second fluid are mixed. There is a risk of doing so. For example, an air conditioning system in which the second fluid is a flammable refrigerant or a harmful refrigerant (hereinafter, these will be described as flammable refrigerants), and the first fluid is circulated indoors and the second fluid is not circulated indoors. When the first fluid and the second fluid are mixed, a flammable refrigerant that should not normally circulate in the room may flow into the room.

Therefore, it is desired that the plate heat exchanger prevent the first fluid and the second fluid from being mixed even if the first heat transfer plate or the second heat transfer plate is damaged by any chance. In the plate heat exchanger, when the area where the first heat transfer plate and the second heat transfer plate are not in contact is damaged, only one of the first heat transfer plate and the second heat transfer plate is damaged. Therefore, the possibility that the first fluid and the second fluid are mixed is reduced. Therefore, in the plate heat exchanger, even if the first heat transfer plate or the second heat transfer plate is damaged, the first heat transfer plate and the second heat transfer plate are not affected by error factors such as manufacturing conditions or environmental conditions. It is desirable that the area that is not in contact with is damaged.

The present invention is for solving the above-mentioned problems, and even if the first heat transfer plate or the second heat transfer plate is damaged, the first heat transfer plate is not affected by error factors such as manufacturing conditions or environmental conditions. It is an object of the present invention to provide a plate type heat exchanger and a heat transfer device in which a region where the heat transfer plate and the second heat transfer plate are not in contact with each other is damaged.

In the plate-type heat exchanger according to the present invention, a plurality of heat transfer plates are laminated, and the first flow path through which the first fluid flows and the second flow path through which the second fluid flows are each of the plurality of heat transfer plates. A main body is provided which is alternately formed with a heat plate as a boundary, and the main body is a heat transfer plate of a first heat transfer plate and a second heat transfer plate which are arranged so as to face each other among a plurality of heat transfer plates. A first flow path is formed between them, and the first flow path has a plate-shaped inner fin in which a plurality of concave-convex bent portions are formed, and the first heat transfer plates face each other 2 It has one plate and a plurality of brazing portions provided between the two plates to connect the two plates, and the two plates and the plurality of braces are contained in the first heat transfer plate. A plurality of gaps, which are spaces formed by the attachment portion, and a communication passage connecting the gaps of the plurality of gaps are formed, and the inner fin is perpendicular to the flow direction of the first fluid. A plurality of uneven pitches formed in a concave-convex shape in the cross section of the inner fin are provided in the flow direction, and at least one uneven pitch is a first pitch that abuts on the first heat transfer plate and the second heat transfer plate. And a second pitch that is in contact with the second heat transfer plate and is larger than the first pitch in the intersecting direction perpendicular to the stacking direction and the flow direction of the plurality of heat transfer plates, and has the inside of the main body. Is projected in the stacking direction, the plurality of voids are formed in the region of the second pitch, and the discharge flow path formed by the plurality of voids and the communication passage communicates with the outside of the main body. It is something that is.

The heat transfer device according to the present invention includes the plate type heat exchanger according to the present invention.

According to the present invention, the inner fins in the first flow path have a first pitch that abuts on the first heat transfer plate and the second heat transfer plate, and a second pitch that abuts on the second heat transfer plate. It has a concavo-convex pitch with. The second pitch is formed larger than the first pitch in the intersecting direction perpendicular to the stacking direction and the distribution direction of the plurality of heat transfer plates. When the inside of the main body is projected in the stacking direction, the plurality of voids are formed in the region of the second pitch. Therefore, the plate of the first heat transfer plate constituting the first flow path is formed so that the position facing the second pitch is lower in strength than the position facing the first pitch. There is. Therefore, even if a factor that causes damage to the first heat transfer plate should occur, the position of the plate of the first heat transfer plate facing the second pitch is higher than the position facing the first pitch. It becomes easy to get hurt. Therefore, even if a factor that damages the plate heat exchanger occurs, the first heat transfer plate and the second heat transfer plate are not in contact with each other regardless of error factors such as manufacturing conditions or environmental conditions. It can be scratched.

It is a schematic block diagram which shows the heat transfer apparatus which concerns on Embodiment 1. FIG. It is an exploded perspective view which shows the plate type heat exchanger which concerns on Embodiment 1. FIG. It is explanatory drawing which shows a part of the plate type heat exchanger which concerns on Embodiment 1 in the cross section. It is a partial perspective view which shows the structure between two 1st inner fins which concerns on Embodiment 1. FIG. It is a perspective view which shows the 1st inner fin which concerns on Embodiment 1. FIG. It is a top view of the 1st inner fin which concerns on Embodiment 1, and is the perspective view when it projected in the overlapping direction of the 1st heat transfer plate and the 2nd heat transfer plate. FIG. 5 is a plan view of the first inner fin according to the first embodiment, and is a view showing only the first inner fin among the perspective views when projected in the overlapping direction of the first heat transfer plate and the second heat transfer plate. be. It is a top view of the 1st inner fin which concerns on Embodiment 1, and shows only the layer of a heat transfer member and a gap part in the perspective view when projected in the overlapping direction of a 1st heat transfer plate and a 2nd heat transfer plate. It is a figure. FIG. 5 is a plan view of the first inner fin according to the second embodiment, and shows only the heat transfer member and the layer of the gap portion in the perspective view when projected in the overlapping direction of the first heat transfer plate and the second heat transfer plate. It is a figure. It is a plan view of the 1st inner fin which concerns on the modification 1 of Embodiment 2, and in the perspective view when it projected in the overlapping direction of a 1st heat transfer plate and a 2nd heat transfer plate, a heat transfer member and a gap part It is the figure which showed only the layer of. It is a plan view of the 1st inner fin which concerns on the modification 2 of Embodiment 2, and in the perspective view when it projected in the overlapping direction of a 1st heat transfer plate and a 2nd heat transfer plate, a heat transfer member and a gap part It is the figure which showed only the layer of. FIG. 5 is a plan view of the first inner fin according to the third embodiment, and shows only the heat transfer member and the layer of the gap portion in the perspective view when projected in the overlapping direction of the first heat transfer plate and the second heat transfer plate. It is a figure. FIG. 3 is a plan view of the first inner fin according to the first modification in the third embodiment, and the heat transfer member and the gap portion in the perspective view when projected in the overlapping direction of the first heat transfer plate and the second heat transfer plate. It is the figure which showed only the layer of. It is explanatory drawing which shows the plate type heat exchanger which concerns on Embodiment 4 in the cross section.

Hereinafter, the plate heat exchanger 30 and the heat transfer device 100 according to the embodiment will be described with reference to the drawings. In the following drawings including FIG. 1, the relative dimensional relationship and shape of each component may differ from the actual ones, and the form of the component shown in the entire specification is merely an example. The description is not limited to these. Further, in the following drawings, those having the same reference numerals are the same or equivalent thereof, and this shall be common to the entire text of the specification. In addition, terms that indicate directions (for example, "top", "bottom", "right", "left", "front", and "rear") are used as appropriate for ease of understanding. For convenience of explanation, it is described as such, and does not limit the arrangement and orientation of the device or component. Further, in the cross-sectional view, hatching is appropriately omitted in view of visibility.

Embodiment 1.
<Structure of heat transfer device 100>
FIG. 1 is a schematic configuration diagram showing a heat transfer device 100 according to the first embodiment. As shown in FIG. 1, the heat transfer device 100 includes a refrigerant circuit 10 that cools or heats a heat medium as a first fluid, and a heat medium circuit 20 that distributes the heat medium inside a house. The refrigerant circuit 10 is mounted on the outdoor unit 11. The heat medium circuit 20 circulates the heat medium from the outdoor unit 11 into the house 21.

<Structure of outdoor unit 11>
The outdoor unit 11 includes a compressor 12, a flow path switching device 13, a plate heat exchanger 30, a decompression device 14, and an outdoor heat exchanger 15. In the outdoor unit 11, the compressor 12, the flow path switching device 13, the plate heat exchanger 30, the decompression device 14, and the outdoor heat exchanger 15 are sequentially connected in order by the refrigerant pipe 16 to form the refrigerant circuit 10. .. The outdoor unit 11 is a heat pump device. A refrigerant, which is a second fluid, flows in the refrigerant circuit 10.

The compressor 101 is a fluid machine that compresses the sucked refrigerant into a high temperature and high pressure state and discharges it. As the compressor 12, various types of compressors such as a scroll compressor and a rotary compressor are used.

The flow path switching device 13 is, for example, a four-way valve, and is a device that switches the flow direction of the refrigerant flowing through the refrigerant circuit 10 between the cooling operation and the heating operation.

The plate heat exchanger 30 functions as an evaporator or a condenser. In the cooling operation, the plate heat exchanger 30 exchanges heat between the heat medium and the refrigerant that has become cold through the decompression device 14. As a result, the heat medium is cooled in the plate heat exchanger 30. Further, in the heating operation, the plate heat exchanger 30 exchanges heat between the heat medium and the refrigerant in the high temperature and high pressure state compressed by the compressor 12. As a result, the heat medium is heated in the plate heat exchanger 30.

The pressure reducing device 14 is, for example, an expansion valve, which is a device for reducing the pressure of the refrigerant. The decompression device 14 functions as a throttle mechanism between the plate heat exchanger 30 and the outdoor heat exchanger 15. As the pressure reducing device 14, an electronic expansion valve whose opening degree is adjusted by the control of the control device can be used.

The outdoor heat exchanger 15 is an air heat exchanger that exchanges heat between the refrigerant circulating inside and the refrigerant and the air that is the outside air. The outdoor heat exchanger 15 functions as a condenser when the plate heat exchanger 30 functions as an evaporator. Further, the outdoor heat exchanger 15 functions as an evaporator when the plate heat exchanger 30 functions as a condenser.

The refrigerant, which is the second fluid, flows through the refrigerant circuit 10 of the outdoor unit 11. As the refrigerant as the second fluid, for example, a flammable refrigerant such as R32 or R290, which is a low GWP refrigerant, is used.

<Structure of heat medium circuit 20>
The heat medium circuit 20 includes a plate heat exchanger 30, a circulation pump 22, and a radiator 23. The heat medium circuit 20 is configured by connecting a plate heat exchanger 30, a circulation pump 22, and a radiator 23 in an annular shape by a heat medium pipe 24.

A heat medium, which is the first fluid, flows through the heat medium circuit 20. The heat medium that is the first fluid is water or brine. The heat medium circuit 20 may include a storage tank (not shown) for storing the heat medium.

The circulation pump 22 imparts a transport force for circulating in a certain direction to the heat medium circulating in the heat medium piping 24. The circulation pump 22 is mounted on the indoor unit 25 in the house 21. The circulation pump 22 may be mounted on the outdoor unit 11.

The radiator 23 cools the interior of the house 21 by the cold heat of the heat medium. Alternatively, the radiator 23 heats the interior of the house 21 by the heat of the heat medium. The heat medium circuit 20 may be provided with an air conditioner other than the radiator 23. Further, the heat medium circuit 20 may be used as a water heater for supplying hot water by using water as the heat medium.

<Others>
The heat transfer device 100 can be used in many industrial or household appliances equipped with a plate heat exchanger 30. For example, the heat transfer device 100 can be used for air conditioning, power generation, heat sterilization treatment equipment for food, and the like.

<Structure of plate heat exchanger 30>
FIG. 2 is an exploded perspective view showing the plate heat exchanger 30 according to the first embodiment. In FIG. 2, the upward direction U, the downward direction D, the right direction R, the left direction L, the front direction F, and the back direction B are shown. In the plate type heat exchanger 30, a plurality of heat transfer plates are laminated, and the first flow path through which the first fluid flows and the second flow path through which the second fluid flows form each heat transfer plate of the plurality of heat transfer plates. It is provided with a main body 30A formed alternately at the boundary.

As shown in FIG. 2, the main body 30A of the plate heat exchanger 30 includes a pair of side plates 31, a plurality of first heat transfer plates 32, a plurality of first inner fins 33, and a plurality of second heat transfer. A plate 34 and a plurality of second inner fins 35 are provided. As the material of various components of the plate heat exchanger 30, a metal such as stainless steel, copper, aluminum or titanium or a synthetic resin can be used. Further, the first heat transfer plate 32 or the second heat transfer plate 34 may be formed of a clad material.

Each of the pair of side plates 31 has a flat plate shape, and a plurality of first heat transfer plates 32, a plurality of first inner fins 33, a plurality of second heat transfer plates 34, and a plurality of second inner fins 35 are defined. It is placed on both sides in the order of, and serves as a reinforcement. On one of the pair of side plates 31, four passage holes of a heat medium inlet 31a, a heat medium outlet 31b, a refrigerant inlet 31c, and a refrigerant outlet 31d are formed at four corners. In FIG. 2, the heat medium inlet 31a is shown in the lower corner on one of the left and right sides on the drawing, the heat medium outlet 31b is shown in the upper corner, the refrigerant inlet 31c is shown in the upper corner on the left and right other side, and the lower corner is shown. Refrigerant outlet 31d is shown. Further, in FIG. 2, the flow direction of the heat medium is indicated by the symbol X of the solid line arrow, and the flow direction of the refrigerant is indicated by the symbol Y of the broken line arrow.

At each of the four corners of the plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34, the four passage holes of the heat medium inlet 31a, the heat medium outlet 31b, the refrigerant inlet 31c and the refrigerant outlet 31d are communicated with each other. A through hole is formed as a passage hole. Specifically, as shown in FIG. 2, the first heat transfer plate 32 is provided with a heat medium outward path hole 31a1, a heat medium return path hole 31b1, a refrigerant outward path hole 31c1, and a refrigerant return path hole 31d1 as passage holes. There is. Similarly, the second heat transfer plate 34 is provided with a heat medium outward path hole 31a2, a heat medium return path hole 31b2, a refrigerant outward path hole 31c2, and a refrigerant return path hole 31d2 as passage holes.

FIG. 3 is an explanatory view showing a part of the plate heat exchanger 30 according to the first embodiment in a cross section. The plurality of first heat transfer plates 32 have a plate 32a and a plate 32b, respectively, which form a flat heat transfer surface. Similarly, the plurality of second heat transfer plates 34 have a plate 34a and a plate 34b, respectively, which form a flat heat transfer surface. The plate 32a, the plate 32b, the plate 34a and the plate 34b are metal plates. The plate 32a, the plate 32b, the plate 34a, and the plate 34b are not limited to the metal plate. In the plate heat exchanger 30, the first heat transfer plate 32 and the second heat transfer plate 34 are alternately laminated.

The first heat transfer plate 32 is formed as a double wall by superimposing two metal plates of the plate 32a and the plate 32b. The double wall is a double wall structure. Similarly, the second heat transfer plate 34 is formed as a double wall by superimposing two metal plates of the plate 34a and the plate 34b.

The first heat transfer plate 32 has two plates of

plates

32a and 32b facing each other, and a plurality of brazing portions 61 provided between the two plates and connecting the two plates. .. In the first heat transfer plate 32, a plurality of gaps 60, which is a space formed by two plates of the

plates

32a and 32b, and a plurality of brazed portions 61, and a gap portion of the plurality of gaps 60. A communication passage 200a (see FIG. 6) connecting the 60s to each other is formed.

More specifically, as shown in FIG. 3, the two metal plates of the plate 32a and the plate 32b are brazed by a brazing portion 61 as a heat transfer member. The brazing portion 61 is partially arranged in the space between the two metal plates of the plate 32a and the plate 32b so as to form a gap portion 60 between the adjacent brazing portions 61. As a result, the two metal plates of the plate 32a and the plate 32b improve the heat transfer efficiency while forming a double wall structure in which the gap portion 60 is sandwiched by the brazing portion 61 which is a heat transfer member.

Similarly, the two metal plates of the plate 34a and the plate 34b are brazed by the brazing portion 61 as a heat transfer member. The brazing portion 61 is partially arranged in the space between the two metal plates of the plate 34a and the plate 34b so as to form a gap portion 60 between the adjacent brazing portions 61. The two metal plates of the plate 34a and the plate 34b improve the heat transfer efficiency while forming a double wall structure in which the gap portion 60 is sandwiched by the brazing portion 61 which is a heat transfer member.

The plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34 are plate-shaped members having a substantially uniform wall thickness, which are unevenly processed by a press or the like. The first heat transfer plate 32 and the second heat transfer plate 34 are formed so that a flange portion for connecting the plates to each other rises by uneven processing around the main portion which is a flat heat transfer surface. The thickness of the plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34 may be appropriately different. When the thickness of the plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34 becomes thick, it is effective in preventing the progress of corrosion and improving the strength of the plate heat exchanger 30. On the other hand, when the thickness of the plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34 becomes thin, the thermal resistance can be reduced, the deterioration of the heat exchange performance can be suppressed, and the material cost can be reduced. As described above, the plate thicknesses of the plurality of first heat transfer plates 32 and the plurality of second heat transfer plates 34 may be selected according to desired conditions.

The plate heat exchanger 30 has a heat medium flow path 38 and a refrigerant flow path 39 formed between the first heat transfer plate 32 and the second heat transfer plate 34. The heat medium flow path 38 is a first flow path through which the heat medium is circulated, and the refrigerant flow path 39 is a second flow path through which the refrigerant is circulated.

The main body 30A of the plate heat exchanger 30 is a first flow path between the first heat transfer plate 32 and the second heat transfer plate 34, which are arranged so as to face each other among the plurality of heat transfer plates. The heat medium flow path 38 is formed. Here, the first heat transfer plate 32 is the first heat transfer plate in the stacking direction FB of the plurality of heat transfer plates, and the second heat transfer plate 34 is the second heat transfer plate.

The main body 30A of the plate heat exchanger 30 has a second flow path between the first heat transfer plate 32 and the other second heat transfer plate 34, which are arranged so as to face each other among the plurality of heat transfer plates. The refrigerant flow path 39 is formed. Here, the first heat transfer plate 32 is the first heat transfer plate in the stacking direction FB of the plurality of heat transfer plates, and the other second heat transfer plate 34 is the third heat transfer plate.

In the main body 30A of the plate heat exchanger 30, heat medium flow paths 38 and refrigerant flow paths 39 are alternately formed in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. The plate heat exchanger 30 causes heat exchange between the heat medium flowing through the heat medium flow path 38 and the refrigerant flowing through the refrigerant flow path 39.

As shown in FIG. 2, the heat medium flow path 38 circulates the heat medium upward in the height direction extending in the upward direction U and the downward direction D. The heat medium flow path 38 goes from the heat medium inlet 31a located below the right direction R of the plate heat exchanger 30 to the heat medium outlet 31b located above the right direction R of the plate heat exchanger 30. As such, the heat medium is circulated upward in the height direction. The heat medium flow path 38 is, for example, from the lower side of the plate heat exchanger 30 in which the heat medium inlet 31a is located in the right direction R to the left side L of the plate heat exchanger 30 in which the refrigerant inlet 31c is located. The heat medium may be circulated by inclining from the height direction so as to face upward.

As shown in FIG. 2, the refrigerant flow path 39 circulates the refrigerant downward in the height direction extending in the upward direction U and the downward direction D. The refrigerant flow path 39 is directed from the refrigerant inlet 31c located above the left direction L of the plate heat exchanger 30 toward the refrigerant outlet 31d located below the left direction L of the plate heat exchanger 30. The refrigerant is circulated downward in the height direction. The refrigerant flow path 39 is, for example, from the upper side of the plate heat exchanger 30 in which the heat medium outlet 31b is located in the right direction R to the lower side of the plate heat exchanger 30 in which the refrigerant outlet 31d is located in the left direction L. The refrigerant may be circulated at an angle from the height direction so as to be directed toward.

The heat medium flow path 38, which is the first flow path formed in the main body 30A of the plate heat exchanger 30, has a plate-shaped first inner fin 33 in which a plurality of unevenly bent portions are formed. is doing. That is, the first inner fin 33 is arranged in the heat medium flow path 38.

The first inner fins 33 are arranged in each of the heat medium flow paths 38, and the uneven pitch 40 is repeatedly formed on the first inner fins 33. A plurality of second inner fins 35 are arranged in the refrigerant flow path 39. The plurality of second inner fins 35 are respectively arranged in the refrigerant flow path 39, and the uneven pitch 50 is repeatedly formed on the plurality of second inner fins 35.

FIG. 4 is a partial perspective view showing a configuration between the two first inner fins 33 according to the first embodiment. FIG. 5 is a perspective view showing the first inner fin 33 according to the first embodiment. The first inner fin 33 and the second inner fin 35 will be described with reference to FIGS. 3 to 5.

The plurality of first inner fins 33 are offset fins arranged between the corresponding first heat transfer plate 32 and the second heat transfer plate 34 to promote heat transfer. Each of the plurality of first inner fins 33 has a substantially plate-like shape in which the width direction and the height direction are larger than those in the thickness direction.

Each of the plurality of first inner fins 33 includes a structure in which a concave-convex pitch 40 in which thin-walled elements are formed at substantially right angles across the right direction R and the left direction L, which are the width directions, is repeated. Of the uneven pitch 40, the top 40c1 or the bottom 40c2 facing each of the first heat transfer plate 32 and the second heat transfer plate 34 is formed on a flat surface. As a result, the plurality of first inner fins 33 come into surface contact with both the corresponding first heat transfer plate 32 and the second heat transfer plate 34 on the flat surface of the top 40c1 or the bottom 40c2, respectively.

The plurality of second inner fins 35 are offset fins arranged between the corresponding first heat transfer plate 32 and the second heat transfer plate 34 to promote heat transfer. Each of the plurality of second inner fins 35 has a substantially plate-like shape in which the width direction and the height direction are larger than those in the thickness direction. The plurality of second inner fins 35 are arranged on the opposite side of the plurality of first inner fins 33 via the first heat transfer plate 32. Further, the plurality of second inner fins 35 are arranged on the opposite side of the plurality of first inner fins 33 via the second heat transfer plate 34. That is, in the plate heat exchanger 30, the first inner fins 33 and the second inner fins 35 are alternately arranged in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34.

Each of the plurality of second inner fins 35 includes a structure in which a concave-convex pitch 50 in which thin-walled elements are formed at substantially right angles over the right direction R and the left direction L, which are the width directions, is repeated. Of the uneven pitch 50, the top 50c1 or the bottom 50c2 facing each of the first heat transfer plate 32 and the second heat transfer plate 34 is formed on a flat surface. As a result, the plurality of second inner fins 35 come into surface contact with both the corresponding first heat transfer plate 32 and the second heat transfer plate 34 on the flat surface of the top 50c1 or the bottom 50c2, respectively.

The uneven pitch 50 formed on the second inner fin 35 has a portion orthogonal to the crossing direction LR with respect to the flow direction DU of the refrigerant flowing through the refrigerant flow path 39, and has a portion extending in parallel with the flow direction DU, and is perpendicular to the portion. The bent portion is formed so as to be continuous.

The uneven pitch 50 formed on the second inner fin 35 has an orthogonal portion 51 extending so as to connect both the plate 32b of the first heat transfer plate 32 and the plate 34a of the second heat transfer plate 34. The orthogonal portion 51 is provided between the plate 32b of the first heat transfer plate 32 and the plate 34a of the second heat transfer plate 34. The orthogonal portion 51 is a portion of the uneven pitch 50 that is orthogonal to the crossing direction LR of the refrigerant flowing through the refrigerant flow path 39 with respect to the flow direction DU.

The orthogonal portion 51 is a wall extending in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. The orthogonal portion 51 is formed so as to extend in a direction orthogonal to the plate surfaces of the plate 32b and the plate 34a. The orthogonal portion 51 extends continuously between the top 50c1 and the bottom 50c2 and between the top 50c1 and the bottom 50c2, and forms a concave-convex shape with a concave-convex pitch 50 together with the top 50c1 and the bottom 50c2. The second inner fin 35 has a concavo-convex shape in which the bottom portion 50c2, the orthogonal portion 51, and the top portion 50c1 repeat in an intersecting direction LR with respect to the flow direction DU of the refrigerant flowing through the refrigerant flow path 39.

The heat transfer area is different between the first inner fin 33 and the second inner fin 35. Specifically, the first inner fin 33 and the second inner fin 35 have different dimensions of the uneven pitch 40 or the uneven pitch 50, as shown in FIGS. 3 and 4, although details will be described later. In FIG. 2, the first inner fin 33 and the second inner fin 35 are shown in the same manner, giving priority to clarity on the drawing.

The plate 32a of the first heat transfer plate 32 and the plate 34b of the second heat transfer plate 34 sandwiching the first inner fin 33 are brazed to the first inner fin 33, respectively. The plate 34a of the second heat transfer plate 34 and the plate 32b of the first heat transfer plate 32 that sandwich the second inner fin 35 are brazed to the second inner fin 35, respectively.

The plate heat exchanger 30 has a laminated structure between one side plate 31 and the other side plate 31. In the laminated structure, as necessary, laminated elements are repeatedly arranged in the order of the first inner fin 33, the first heat transfer plate 32, the second inner fin 35, and the second heat transfer plate 34.

<Details of plate heat exchanger 30>
As shown in FIGS. 3 to 5, the first inner fin 33 has an uneven pitch 40. Specifically, the first inner fin 33 has a plurality of uneven pitches 40 in the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. The first inner fin 33 has a plurality of uneven pitches 40 formed in a rectangular wave shape in the cross section of the first inner fin 33 perpendicular to the flow direction DU of the first fluid in the flow direction DU.

The uneven pitch 40 is provided in the intersecting direction LR with respect to the height direction extending in the upward direction U and the downward direction D, which is the distribution direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. Has been done. Here, the uneven pitch 40 is a width direction extending between the right direction R and the left direction L, which are directions orthogonal to the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. It is provided in.

The uneven pitch 40 forms a flow path hole extending in the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. The uneven pitch 40 has a shape in which unevenness is repeated in the crossing direction LR with respect to the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. The uneven pitch 40 aligns the plate surface with the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged, and does not block the flow of the heat medium flowing through the heat medium flow path 38. ..

A part of the uneven pitch 40 is from the first pitch 40a and the first pitch 40a in the direction intersecting the direction in which the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged flows. Also has a second pitch 40b with a wide pitch width. Further, among the plurality of uneven pitches 40 provided in the heat medium distribution direction DU, some of the uneven pitches 40 are the distribution directions of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. It has only the first pitch 40a in the direction intersecting the DU. At least one or more uneven pitch 40 of the first inner fin 33 has a first pitch 40a and a second pitch 40b.

The first pitch 40a of the portion constituting the top portion 40c1 comes into contact with the plate 34b of the second heat transfer plate 34. Further, the first pitch 40a of the portion constituting the bottom portion 40c2 comes into contact with the plate 32a of the first heat transfer plate 32. The second pitch 40b of the portion constituting the top portion 40c1 comes into contact with the plate 34b of the second heat transfer plate 34. In the second pitch 40b, the width of the crossing direction LR is larger than the width of the crossing direction LR of the first pitch 40a in the crossing direction LR perpendicular to the stacking direction FB and the distribution direction DU of the plurality of heat transfer plates.

The uneven pitch 40 formed on the first inner fin 33 has a portion orthogonal to the crossing direction LR of the heat medium flowing through the heat medium flow path 38 with respect to the distribution direction DU and a portion extending parallel to the flow direction DU. , The portions that bend at right angles are formed to be continuous.

The uneven pitch 40 formed on the first inner fin 33 has an orthogonal portion 41 extending so as to connect both the plate 32a of the first heat transfer plate 32 and the plate 34b of the second heat transfer plate 34. The orthogonal portion 41 is provided between the plate 32a of the first heat transfer plate 32 and the plate 34b of the second heat transfer plate 34. The orthogonal portion 41 is a portion of the uneven pitch 40 that is orthogonal to the crossing direction LR of the heat medium flowing through the heat medium flow path 38 with respect to the distribution direction DU.

The orthogonal portion 41 is a wall extending in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. The orthogonal portion 41 is formed so as to extend in a direction orthogonal to the plate surfaces of the plates 32a and 34b. The orthogonal portion 41 extends continuously between the top 40c1 and the bottom 40c2 and between the top 40c1 and the bottom 40c2, and forms a concave-convex shape with a concave-convex pitch 40 together with the top 40c1 and the bottom 40c2. The first inner fin 33 forms a concavo-convex shape in which the bottom portion 40c2, the orthogonal portion 41, and the top portion 40c1 repeat in an intersecting direction LR with respect to the distribution direction DU of the heat medium flowing through the heat medium flow path 38.

As shown in FIG. 3, the orthogonal portion 41 heats with respect to the orthogonal portion 41 of the uneven pitch 40 in relation to the adjacent uneven pitch 40 in the distribution direction DU of the heat medium flowing through the heat medium flow path 38. It is provided so as to be offset from the crossing direction LR with respect to the distribution direction DU of the medium. Therefore, the orthogonal portion 41 is located between the two orthogonal portions 41 having the uneven pitch 40 adjacent to the heat medium distribution direction DU when the first inner fin 33 is viewed in the heat medium distribution direction DU. It is provided. In particular, when the first inner fin 33 is viewed in the heat medium distribution direction DU, the orthogonal portion 41 is formed at the uneven pitch 40 with respect to the adjacent uneven pitch 40 in the heat medium distribution direction DU. It is preferable that it is provided so as to be located at the center between the adjacent orthogonal portions 41.

The second pitch 40b has at least one first pitch 40a in the crossing direction LR with respect to the distribution direction DU of the heat medium flowing through the heat medium flow paths 38 in the plurality of first inner fins 33. 1 or more are provided.

For example, as shown in FIGS. 4 and 5, at the uppermost portion of the uneven pitch 40 in which the second pitch 40b is formed, the second pitch 40b is the heat medium flow path 38 in the plurality of first inner fins 33. Two first pitches 40a are provided at one pitch in the crossing direction LR with respect to the circulation direction DU of the heat medium flowing through the heat medium. The number of first pitches 40a formed between the two second pitches 40b is not limited to nine. The number of the first pitch 40a formed between the two second pitches 40b may be 8 or less, or 10 or more. The uppermost portion of the uneven pitch 40 represents the uneven pitch 40 located on the uppermost U side in the distribution direction DU of the heat medium in the first inner fins 33 shown in FIGS. 4 and 5. .. Further, 1 pitch means one of a plurality of uneven pitches 40 formed in the distribution direction DU of the heat medium.

Further, as shown in FIGS. 4 and 5, in the uneven pitch 40 other than the uppermost portion, the second pitch 40b is the distribution direction DU of the heat medium flowing through the heat medium flow path 38 in the plurality of first inner fins 33. On the other hand, one is provided at one pitch in the crossing direction LR.

As shown in FIGS. 4 and 5, the second pitch 40b formed at the uneven pitch 40 is formed at another uneven pitch 40 located immediately before and after the uneven pitch 40 in the distribution direction DU of the heat medium. It is provided so as to be offset from the second pitch 40b in the crossing direction LR. As shown in FIGS. 4 and 5, in the first inner fin 33, the second pitch 40b is arranged in a staggered pattern, but the second pitch 40b is limited to the configuration in which the second pitch 40b is arranged in a staggered pattern. It may be arranged in a grid pattern, for example.

As shown in FIG. 4, in the flow direction DU of the heat medium, between the uneven pitch 40 having the second pitch 40b and the uneven pitch 40 having the second pitch 40b whose formation position is different from that of the second pitch 40b. Is provided with a concave-convex pitch 40 having only the first pitch 40a. That is, the first inner fin 33 has a first uneven pitch 40 having a first pitch 40a and a second pitch 40b, and a second unevenness having a first pitch 40a and a second pitch 40b in the distribution direction DU. It has a pitch of 40 and. The first inner fin 33 has a third uneven pitch 40 having only the first pitch 40a between the first concave-convex pitch 40 and the second concave-convex pitch 40.

As shown in FIGS. 4 and 5, the uneven pitch 40 formed only by the first pitch 40a is formed in a row between the uneven pitch 40s having the second pitch 40b in the distribution direction DU. There is. However, the number of uneven pitches 40 formed only by the first pitch 40a between the uneven pitches 40 having the second pitch 40b is not limited to one row, and may be two or more rows. Further, the number of uneven pitches 40 formed only by the first pitch 40a between the uneven pitches 40 having the second pitch 40b may be the same number or different numbers depending on different positions in the distribution direction DU. ..

Further, the rows formed only by the first pitch 40a in the distribution direction DU may be formed as one row between the rows having the second pitch 40b in the distribution direction DU, or may be formed in a plurality of rows. ..

As shown in FIGS. 3 and 4, the uneven pitch 40 having the second pitch 40b is the first inner fin 33 arranged adjacent to the first heat transfer plate 32 and the second heat transfer plate 34 in the stacking direction FB. Facing the uneven pitch 40 having only the first pitch 40a of the above. This configuration is applied to any part of the plate heat exchanger 30 in the flow direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged.

As shown in FIGS. 4 and 5, the plurality of second pitches 40b provided on the first inner fin 33 open the same side in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. is doing.

The value obtained by dividing the pitch width P1 of the first pitch 40a shown in FIG. 3 by the pitch width P2 of the second pitch 40b is smaller than 1. More preferably, the value obtained by dividing the pitch width P1 of the first pitch 40a by the pitch width P2 of the second pitch 40b is smaller than 1 and larger than 0.5.

<Details of brazing part 61>
As shown in FIG. 3, a brazing portion 61, which is a heat transfer member, is provided between the two metal plates of the plate 32a and the plate 32b. The two metal plates, the plate 32a and the plate 32b, are brazed by a brazing portion 61 as a heat transfer member. Similarly, a brazing portion 61, which is a heat transfer member, is provided between the two metal plates of the plate 34a and the plate 34b. The two metal plates, the plate 34a and the plate 34b, are brazed by a brazing portion 61 as a heat transfer member.

The brazing portion 61 is partially arranged in the space between the two metal plates of the plate 32a and the plate 32b so as to form a gap portion 60 between the adjacent brazing portions 61. Therefore, as shown in FIG. 3, a gap 60 is formed between the two metal plates of the plate 32a and the plate 32b. Similarly, the brazing portion 61 is partially arranged in the space between the two metal plates of the plate 34a and the plate 34b so as to form a gap 60 between the adjacent brazing portions 61. There is. Therefore, a gap 60 is formed between the two metal plates of the plate 34a and the plate 34b.

As the brazing material of the brazing portion 61, any brazing material may be used as long as it is a material having higher heat transfer property than air, such as copper brazing, silver brazing, or metal brazing such as phosphorus deoxidized copper. Further, as the heat transfer member, in addition to the brazed portion 61, a heat transfer member such as metal may be provided by adhesion or the like. Further, the heat transfer member may be a liquid or solid material having high adhesion such as grease.

The heat transfer member may be integrated by directly joining two metal plates of the plate 32a and the plate 32b by spot welding or pressure joining without interposing a separate part. Similarly, the heat transfer member may be integrated by directly joining two metal plates of the plate 34a and the plate 34b by spot welding or pressure joining without interposing a separate part. However, when the two metal plates are directly joined, it is necessary to provide the gap 60.

When the brazing portion 61 is projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the brazing portion 61 is provided in the region of the first pitch 40a. In other words, when the brazing portion 61 is projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the brazing portion 61 does not exist in the region of the second pitch 40b.

FIG. 7 is a plan view of the first inner fin 33 according to the first embodiment, and is the first perspective view when projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. It is a figure which showed only the inner fin 33. FIG. 8 is a plan view of the first inner fin 33 according to the first embodiment, and is a perspective view of the first heat transfer plate 32 and the second heat transfer plate 34 projected onto the stacking direction FB. It is a figure which showed only the layer of a member and a gap 60. Note that FIG. 8 omits the illustration of heat transfer members such as the brazed portion 61. Further, FIGS. 7 and 8 show a part of the distribution direction DU of the first inner fin 33.

The uneven pitch 40 of the first heat transfer plate 32, the second heat transfer plate 34, the first inner fin 33, the uneven pitch 50 of the second inner fin 35, and the positions of the layers of the heat transfer member and the gap 60 are specified. There is a relationship. In FIGS. 4 and 6, the first inner fin 33 is in front of the plate 32a constituting the first heat transfer plate 32, and the layer of the heat transfer member and the gap 60 constitutes the first heat transfer plate 32a. It shows that it is in the back of. FIG. 6 shows that when the plate heat exchanger 30 is viewed through the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the first inner fin 33, the heat transfer member, and the gap portion 60 are formed. It shows the positional relationship with the layer. In this way, when the plate heat exchanger 30 is seen through the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the plate surface of the first heat transfer plate 32 and the second heat transfer plate 34 The positional relationship with the plate surface will be described as "when projected onto the stacking direction FB".

As shown in FIGS. 3 and 4, the first inner fin 33 abuts on one surface of the plate 32a constituting the first heat transfer plate 32, and the other surface of the plate 32a constituting the first heat transfer plate 32. There is a layer of the heat transfer member and the gap 60 on the side. In FIG. 6, the joining between the first inner fin 33 and the plate 32a is not shown. However, basically, as shown in FIG. 3, in the portion where the first inner fin 33 and the plate 32a constituting the first heat transfer plate 32 are not joined, the first inner is interposed through the plate 32a. A gap 60 is formed on the side opposite to the side where the fins 33 are arranged.

However, as shown in FIG. 3, when the size of the gap portion 60 is larger than the uneven pitch 40 of the first inner fin 33, a part of the plate 32a on the opposite side of the position where the gap portion 60 is formed. The first inner fin 33 may be joined to. In this case, the size of the gap portion 60 and the size of the uneven pitch 40 of the first inner fin 33 are the sizes in the direction in which the plate surfaces of the first heat transfer plate 32 and the second heat transfer plate 34 extend. ..

In the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, it is desirable that there is no brazing portion 61 in the region before and after the second pitch 40b. Then, at least the entire second pitch 40b is formed at a position facing the gap 60 via the plate 32a. In other words, as shown in FIG. 6, when the plate heat exchanger 30 is seen through in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, it is within the formation range of the gap 60. The second pitch 40b is formed.

As shown in FIG. 3, in the stacking direction FB, the flat surface 40b1 of the second pitch 40b is in contact with the plate 34b of the second heat transfer plate 34. As shown in FIG. 3, in the stacking direction FB, the flat surface 40b1 of the second pitch 40b is not in contact with the plate 32a of the first heat transfer plate 32. In the stacking direction FB between the plate 34b and the plate 32a, the opening 40b2 of the second pitch 40b is located on the plate 32a side. The flat surface 40b1 of the second pitch 40b faces the plate 32a via the heat medium flow path 38.

As shown in FIGS. 6 to 8, in the layer in which the gap portion 60 is formed, a continuous passage 200a connecting the gap portions 60 to each other is formed. The communication passage 200a is configured to communicate with the outside air located outside the plate heat exchanger 30.

As shown in FIG. 8, the communication passage 200a is connected to the front and rear gaps 60 closest to the flow direction DU of the first fluid so as to be connected by the shortest path. Note that FIG. 6 shows the upper corner of the first gap 60 in the left direction L and diagonally upward to the left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the right direction R of No. 2 is connected by a communication passage 200a. Further, FIG. 6 shows a third position located at the lower corner of the first gap 60 in the left direction L and diagonally lower left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The upper corner of the gap portion 60 in the right direction R is connected by a communication passage 200a. The communication passage 200a is formed so as to connect the gaps 60 formed alternately on the left and right in the flow direction DU of the first fluid.

The passage width of the continuous passage 200a is smaller than the short size of the gap 60. Further, the flow path cross-sectional area of the communication passage 200a is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60.

The second gap 60 with respect to the first gap 60 is a third gap 60 with respect to the first gap 60 located immediately behind the first gap 60 in the flow direction DU of the first fluid. It becomes. Similarly, the third gap 60 with respect to the first gap 60 is a second with respect to the first gap 60 located immediately before the first gap 60 in the flow direction DU of the first fluid. It becomes the gap 60. In the plate heat exchanger 30, the gap portion 60 and the communication passage 200a are connected to form the discharge passage 200a1.

The discharge flow path 200a1 includes a first row gap portion 60 arranged in the flow direction DU, a second row gap portion 60 formed next to the first row gap portion 60 in the crossing direction LR, and a second row gap portion 60. It is formed by a communication passage 200a connecting the gap portion 60 in the first row and the gap portion 60 in the second row.

The discharge flow path 200a1 is formed so that the closest front and rear gaps 60 among the plurality of gaps 60 are connected by the communication passage 200a and extend in the flow direction DU in the flow direction DU of the first fluid. The end of the discharge flow path 200a1 communicates with the outside of the main body 30A. The discharge flow path 200a1 formed by connecting the gap portion 60 and the communication passage 200a has the same passage direction as the flow direction DU of the first fluid flowing through the heat medium flow path 38 which is the first flow path. It is formed to be.

In the plate heat exchanger 30, when the inside of the main body 30A is projected in the stacking direction FB, a plurality of gaps 60 are formed in the region of the second pitch 40b. Further, in the plate heat exchanger 30, the discharge flow path 200a1 formed by the plurality of gaps 60 and the communication passage 200a communicates with the outside of the main body 30A.

<Action of brazing part 61>
The operation of the brazing portion 61 provided between the two metal plates of the plate 32a and the plate 32b of the first heat transfer plate 32 will be described. Similarly, the operation of the brazing portion 61 of the second heat transfer plate 34 provided between the two metal plates of the plate 34a and the plate 34b will be described.

The brazed portion 61 between the two metal plates of the plate 32a and the plate 32b and the brazed portion 61 between the two metal plates of the plate 34a and the plate 34b have high thermal conductivity. Therefore, the plate heat exchanger 30 can reduce the contact thermal resistance between the two metal plates of the plate 32a and the plate 32b, and the contact thermal resistance between the two metal plates of the plate 34a and the plate 34b. Can be reduced. Therefore, the plate-type heat exchanger 30 can suppress a decrease in heat exchange performance as compared with the case where the brazing portion 61 is not provided.

On the other hand, the plate heat exchanger 30 has an unbrazed gap 60 between the two metal plates of the plate 32a and the plate 32b, and is between the two metal plates of the plate 34a and the plate 34b. It has a gap 60 that is not brazed. The plate-type heat exchanger 30 is configured such that the gaps 60 are connected to each other by a communication passage 200a, and the discharge passage 200a1 formed by the gap 60 and the communication passage 200a communicates with the outside air. ..

Therefore, when the plate 32a of the first heat transfer plate 32 is damaged, the heat medium is released to the outside air through the discharge flow path 200a1. Further, by detecting the leaked fluid flowing out to the outside with a detection sensor (not shown), the control device (not shown) can stop the heat transfer device 100 provided with the plate heat exchanger 30. ..

Here, when each component of the plate heat exchanger 30 is projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the plate 32a is located at the position of the second pitch 40b. The gap 60 formed between the plate 34b and the plate 34b is always formed.

Further, the communication passage 200a is connected so as to be connected to the front and rear gaps 60 closest to the flow direction DU of the first fluid by the shortest path, and the passage width is smaller than the short dimension of the gap 60. ing. Therefore, the plate heat exchanger 30 can suppress performance deterioration due to a decrease in the area ratio of the brazing portion 61.

In the first inner fin 33, the pitch width of the second pitch 40b is longer than the pitch width of the first pitch 40a. Therefore, for example, when the heat medium is water and a higher pressure than usual is generated in the heat medium flow path 38 due to freezing or an increase in internal pressure, the plate 32a is generated at a position facing the second pitch 40b. The stress is higher than the surrounding area. As a result, even if the first heat transfer plate 32 is damaged in the plate heat exchanger 30, the damaged portion of the first heat transfer plate 32 can be set to be the position of the second pitch 40b.

In the plate heat exchanger 30, even if an excessive pressure rise occurs in the heat medium flow path 38, even if the first heat transfer plate 32 is damaged by the provision of the plurality of second pitches 40b, the first one. A damaged part of the heat transfer plate 32 can be planned. Then, the plate heat exchanger 30 can discharge the leaked heat medium to the outside. Further, in the plate type heat exchanger 30, due to the configuration, the joint portion between the plate 32a of the first heat transfer plate 32 and the plate 34b of the second heat transfer plate 34 is damaged, so that the leaked refrigerant leaks through the heat medium circuit 20 into the house. It is possible to prevent the inflow into the 21.

<Details of uneven pitch 50 of the second inner fin 35>
As shown in FIGS. 3 and 4, the uneven pitch 50 of the second inner fin 35 is formed by repeating unevenness with a constant pitch width. The uneven pitch 50 of the second inner fin 35 is not provided with a second pitch 40b like the uneven pitch 40 of the first inner fin 33. In the crossing direction LR, which is the width direction of the plate heat exchanger 30, the pitch width P3 of the uneven pitch 50 formed on the second inner fin 35 is the pitch width P1 of the uneven pitch 40 formed on the first inner fin 33. And the pitch width is smaller than P2, and the unevenness is fine.

Here, the first inner fin 33 and the flat heat transfer surface of the plate 32a constituting the first heat transfer plate 32 and the flat heat transfer surface of the plate 34b forming the second heat transfer plate 34 are face-to-face with each other. It is joined with. Further, the second inner fin 35 and the flat heat transfer surface of the plate 32b forming the first heat transfer plate 32 and the flat heat transfer surface of the plate 34a forming the second heat transfer plate 34 are surface-to-face with each other. It is joined.

Therefore, when the heat medium is a fluid having a high pressure and the refrigerant is a fluid having a low pressure, the first inner fin 33 and the second inner fin 35 used in the plate heat exchanger 30 are as follows. It should be configured. In the plate heat exchanger 30, the uneven pitch 40 has a larger contact area with the first heat transfer plate 32 and the second heat transfer plate 34 than the uneven pitch 50 in the heat medium flow path 38 through which the heat medium flows. It is preferable to use the first inner fin 33 in which the above is formed. The plate heat exchanger 30 has a concave-convex pitch 50 in which the contact area between the first heat transfer plate 32 and the second heat transfer plate 34 is smaller than that of the concave-convex pitch 40 in the refrigerant flow path 39 through which the refrigerant flows. It is preferable to use the second inner fin 35 in which the above is formed. As a result, the plate heat exchanger 30 can obtain the necessary and sufficient strength for each part, and can secure the strength without waste as a whole.

As described above, in the plate heat exchanger 30, fins having a small pitch dimension with good heat transfer and fine irregularities are used in the flow path on the refrigerant side, which has a large influence of pressure loss on the flow path on the heat medium side. .. Then, in the plate heat exchanger 30, fins having a large pitch dimension in which heat transfer is not good but pressure loss is small are used in the flow path on the heat medium side with respect to the flow path on the refrigerant side. As a result, the plate heat exchanger 30 can have the same thermal resistance ratio between the refrigerant and water. In this way, in the plate heat exchanger 30, the thermal resistance ratio between the heat medium as the first fluid and the refrigerant as the second fluid can be adjusted according to the physical properties of the flowing fluid, and the heat exchange efficiency can be improved. can.

<Action>
As described above, the plate heat exchanger 30 and the heat transfer device 100 can maintain the same thermal resistance ratio between the heat medium for heat exchange and the refrigerant. Further, the plate heat exchanger 30 and the heat transfer device 100 can maintain good heat exchange efficiency between the heat medium for heat exchange and the refrigerant. The plate heat exchanger 30 has a simple structure and can be manufactured at low cost, but can prevent the refrigerant from entering the house 21 via the heat medium circuit 20 for a long period of time of the heat transfer device 100. Can improve the reliability of. _{Therefore, the plate heat exchanger 30 and the heat transfer device 100 can use natural refrigerants such as CO 2} , flammable hydrocarbons, low GWP refrigerants, etc., which could not be used until now because they do not have a refrigerant infiltration prevention function. .. Further, since the plate type heat exchanger 30 and the heat transfer device 100 increase the selection range of the fluid to be used, a refrigerant having a large latent heat can be selected and the heat exchange performance can be improved.

<Effect of Embodiment 1>
According to the first embodiment, in the plate type heat exchanger 30, a plurality of first heat transfer plates 32 and a plurality of second heat transfer plates 34, each having a flat heat transfer surface, are alternately laminated. There is. In the plate heat exchanger 30, the heat medium flow path 38 as the first flow path through which the heat medium is circulated and the refrigerant flow path 39 as the second flow path through which the refrigerant is circulated are alternately formed. .. Further, the plate heat exchanger 30 includes a first inner fin 33 arranged in each of the plurality of heat medium flow paths 38 and a second inner fin 35 arranged in each of the plurality of refrigerant flow paths 39. .. Further, a plurality of uneven pitches 40 are repeatedly formed on the first inner fin 33, and a plurality of uneven pitches 50 are repeatedly formed on the second inner fin 35.

The first heat transfer plate 32 is formed as a double wall by superimposing two metal plates of the plate 32a and the plate 32b. The second heat transfer plate 34 is formed as a double wall by superimposing two metal plates of the plate 34a and the plate 34b. The plate heat exchanger 30 has a gap 60 between two metal plates of the plate 32a and the plate 32b, and a brazed portion 61 as a heat transfer member partially arranged. Further, the plate heat exchanger 30 has a gap portion 60 between two metal plates of the plate 34a and the plate 34b, and a brazing portion 61 as a heat transfer member partially arranged. There is. The gaps 60 are connected to each other by a communication passage 200a, and the discharge passage 200a1 formed by the gap 60 and the communication passage 200a is configured to communicate with the outside air.

The uneven pitch 40 extending in the crossing direction LR with respect to the flow direction DU of the heat medium as the first fluid flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged is the first pitch 40a and the first pitch. It has a second pitch 40b having a pitch width wider than 40a. When the brazing portion 61 is projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the brazing portion 61 is provided in the region of the first pitch 40a.

According to this configuration, the plate 32a of the first heat transfer plate 32 and the plate 34b of the second heat transfer plate 34 have a narrow pitch width and are strong at the position where the brazed portion 61 exists in the stacking direction FB. It is connected to 1 pitch 40a.

At the position of the second pitch 40b where the pitch width is wide, the first inner fin 33 does not come into contact with the plate 32a of the first heat transfer plate 32 in the stacking direction FB. Then, in the plate heat exchanger 30, the gap portion 60 formed between the plate 32a and the plate 32b of the first heat transfer plate 32 is located at a position where the second pitch 40b is arranged via the plate 32a. It is configured to face the heat medium flow path 38. In other words, in the plate heat exchanger 30, when the inside of the main body 30A is projected in the stacking direction FB, the plurality of gaps 60 are formed in the region of the second pitch 40b. Therefore, the plate 32a of the first heat transfer plate 32 constituting the heat medium flow path 38 has a higher strength at a position facing the second pitch 40b than at a position facing the first pitch 40a. It's getting low.

Therefore, even if a factor that causes damage to the first heat transfer plate 32 occurs, the plate 32a of the first heat transfer plate 32 faces the second pitch 40b rather than the position facing the first pitch 40a. The position where you are is easily damaged. Therefore, even if a factor of damage occurs in the plate heat exchanger 30, the region where the first heat transfer plate 32 and the second heat transfer plate 34 are not in contact with each other regardless of error factors such as manufacturing conditions or environmental conditions. Can be scratched.

Further, in the plate heat exchanger 30, the discharge passage 200a1 formed by the plurality of gaps 60 and the communication passage 200a communicates with the outside of the main body 30A. That is, the gaps 60 are connected to each other by a communication passage 200a and are configured to communicate with the outside air. Therefore, in the plate heat exchanger 30, the heat medium is released to the atmosphere, and the heat transfer device 100 provided with the plate heat exchanger 30 detects the leaked fluid flowing out to the outside with a detection sensor, and the detection sensor. The heat transfer device 100 can be stopped based on the detection of.

As described above, the plate heat exchanger 30 and the heat transfer device 100 have good heat exchange efficiency, have a simple structure, can be manufactured at low cost, can prevent mixing of the heat medium and the refrigerant, or detect refrigerant leakage. To facilitate. According to the plate heat exchanger 30 of the first embodiment, an air conditioning system in which the second fluid is a flammable refrigerant, the heat transfer device 100 circulates the first fluid indoors, and the second fluid does not circulate indoors. In this case, it is possible to prevent the flammable refrigerant, which should not normally circulate in the room, from flowing into the house 21 via the heat medium circuit 20, and the safety can be improved.

According to the first embodiment, the communication passage 200a is connected so as to be connected to the front and rear gaps 60 closest to the flow direction DU of the first fluid by the shortest path, and the passage width is the short side of the gap 60. It consists of dimensions smaller than the dimensions. Therefore, the plate heat exchanger 30 can suppress performance deterioration due to a decrease in the area ratio of the brazing portion 61.

Further, the flow path cross-sectional area of the continuous passage 200a is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. Therefore, the plate heat exchanger 30 can suppress performance deterioration due to a decrease in the area ratio of the brazing portion 61.

Further, the discharge flow path 200a1 is formed so that the closest front and rear gaps 60 among the plurality of gaps 60 in the flow direction DU of the first fluid are connected by the communication passage 200a and extend in the flow direction DU. , The end of the discharge flow path 200a1 communicates with the outside of the main body 30A. Therefore, in the plate heat exchanger 30, the heat medium is released to the atmosphere, and the heat transfer device 100 provided with the plate heat exchanger 30 detects the leaked fluid flowing out to the outside with a detection sensor, and the detection sensor. The heat transfer device 100 can be stopped based on the detection of.

According to the first embodiment, when the inside of the main body 30A is projected in the stacking direction FB, the plurality of gaps 60 are not formed in the region of the first pitch 40a. Therefore, the plate 32a of the first heat transfer plate 32 constituting the heat medium flow path 38 has a higher strength at a position facing the first pitch 40a than at a position facing the second pitch 40b. It's getting higher.

According to the first embodiment, when the brazing portion 61 is projected on the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the brazing portion 61 is located in the region of the second pitch 40b. Does not exist. According to this configuration, the second pitch 40b has a wider pitch than the first pitch 40a, and the position of the second pitch 40b faces the gap 60 via the plate 32a of the first heat transfer plate 32. Can be configured at the desired position. The gap portion 60 is a portion between the first heat transfer plate 32 and the second heat transfer plate 34 without the brazing portion 61. Therefore, even if a factor that damages the plate heat exchanger 30 should occur, the plate 32a of the first heat transfer plate 32 faces the second pitch 40b rather than the position facing the first pitch 40a. The position where you are is easily damaged.

According to the first embodiment, the first pitch 40b is at least one or more in the crossing direction LR with respect to the distribution direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. One or more are provided in one pitch with the pitch 40a in between. According to this configuration, the plate heat exchanger 30 has a second inner fin 33 so that the plate 32a at a position facing the second pitch 40b is provided at a position facing the region where the pressure rise occurs. A pitch 40b is formed. The plate 32a at a position facing the second pitch 40b has a lower strength than the plate 32a at a position facing the first pitch 40a, and when the pressure in the heat medium flow path 38 rises excessively, the first plate 32a It is more easily damaged than the plate 32a at a position facing 1 pitch 40a.

Further, the second pitch 40b formed at the uneven pitch 40 is formed at another uneven pitch 40 located immediately before and after the uneven pitch 40 in the distribution direction DU of the heat medium flowing through the heat medium flow path 38. It is provided so as to be offset from the second pitch 40b in the crossing direction LR. According to this configuration, in the plate heat exchanger 30, a plurality of second pitches 40b are formed adjacent to each other in the distribution direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. Also, the plurality of second pitches 40b are not continuously formed. As a result, in the plate heat exchanger 30, the plate 32a at a position facing the second pitch 40b does not become excessively fragile.

Further, in the distribution direction DU of the heat medium, between the uneven pitch 40 having the second pitch 40b and the uneven pitch 40 having another second pitch 40b formed at a position different from the uneven pitch 40. Another uneven pitch 40 having only the first pitch 40a is provided. According to this configuration, in the plate heat exchanger 30, a plurality of second pitches 40b are formed adjacent to each other in the distribution direction DU of the heat medium flowing through the heat medium flow path 38 in which the first inner fin 33 is arranged. Also, the plurality of second pitches 40b are not continuously formed. As a result, in the plate heat exchanger 30, the plate 32a at a position facing the second pitch 40b does not become excessively fragile.

According to the first embodiment, the value obtained by dividing the pitch width P1 of the first pitch 40a by the pitch width P2 of the second pitch 40b is smaller than 1. According to this configuration, the plate heat exchanger 30 can easily manage the fragility of the first heat transfer plate 32 at a position facing the second pitch 40b. According to the first embodiment, the value obtained by dividing the pitch width P1 of the first pitch 40a by the pitch width P2 of the second pitch 40b is larger than 0.5. According to this configuration, in the plate heat exchanger 30, the plate 32a at the position facing the second pitch 40b has a certain strength without becoming excessively fragile, and the plate at the position facing the second pitch 40b. It is easy to manage the fragility of 32a.

According to the first embodiment, the uneven pitch 40 of the first inner fin 33 extends parallel to the portion orthogonal to the intersecting direction LR with respect to the distribution direction DU of the heat medium flowing through the heat medium flow path 38. It has a portion and is formed so that a portion that bends at a right angle is continuous. According to this configuration, the first inner fin 33 is easy to process and easy to manufacture.

According to the first embodiment, the heat medium as the first fluid is water or brine. Here, it is assumed that the first heat transfer plate 32 is damaged when the heat medium causes deposition expansion or an excessive pressure rise in the heat medium flow path 38 due to freezing or the like. Since the plate 32a at the position facing the second pitch 40b has lower strength than the plate 32a at the position facing the first pitch 40a, it is more easily damaged than the plate 32a at the position facing the first pitch 40a. There is. Then, when the plate 32a of the first heat transfer plate 32 is damaged at a position facing the second pitch 40b, the plate heat exchanger 30 can discharge the heat medium to the gap portion 60.

According to the first embodiment, the second fluid flowing through the refrigerant flow path 39 is a refrigerant. The plate heat exchanger 30 can discharge the heat medium to the gap 60 when the plate 32a of the first heat transfer plate 32 is damaged at a position facing the second pitch 40b. Therefore, even if the refrigerant is a refrigerant such as a flammable refrigerant and the plate 32a of the first heat transfer plate 32 is destroyed at a position facing the second pitch 40b, the heat medium and the refrigerant are not mixed. Therefore, it is possible to prevent a refrigerant such as a flammable refrigerant from flowing into the house 21 via the heat medium circuit 20 through which the heat medium flows, and it is possible to improve safety.

The uneven pitch 50 of the second inner fin 35 arranged in the refrigerant flow path 39 is formed by repeating unevenness with a constant pitch width. The uneven pitch 50 of the second inner fin 35 is not provided with a second pitch 40b like the uneven pitch 40 of the first inner fin 33. In the crossing direction LR, which is the width direction of the plate heat exchanger 30, the pitch width P3 of the uneven pitch 50 formed on the second inner fin 35 is the pitch width P1 of the uneven pitch 40 formed on the first inner fin 33. And the pitch width is smaller than P2, and the unevenness is fine. Therefore, the refrigerant flow path 39 through which the refrigerant such as the flammable refrigerant flows has higher strength than the heat medium flow path 38 in which the first inner fin 33 having the second pitch 40b is arranged, and is higher than the heat medium flow path 38. It is hard to get hurt in comparison. Therefore, the plate heat exchanger 30 can prevent the refrigerant from flowing into the gap 60 from the refrigerant flow path 39.

According to the first embodiment, in the crossing direction LR, the pitch width P3 of the uneven pitch 50 formed on the second inner fin 35 is the pitch width P1 and the pitch width of the uneven pitch 40 formed on the first inner fin 33. It is smaller than P2 and has fine irregularities. According to this configuration, in the plate heat exchanger 30, the uneven pitch 40 and the uneven pitch 50 can be optimally configured according to the physical characteristics such as the viscosity of each of the heat medium and the refrigerant.

According to the first embodiment, the heat transfer device 100 includes the above-mentioned plate heat exchanger 30. Therefore, the heat transfer device 100 can exert the above-mentioned effect of the plate heat exchanger 30. For example, in the heat transfer device 100, even if a factor that damages the plate heat exchanger 30 should occur, the first heat transfer plate 32 and the second heat transfer plate 34 are connected regardless of error factors such as manufacturing conditions or environmental conditions. The area that is not in contact can be scratched.

Embodiment 2.
FIG. 9 is a plan view of the first inner fin 33 according to the second embodiment, and is a perspective view of the first heat transfer plate 32 and the second heat transfer plate 34 projected onto the stacking direction FB. It is a figure which showed only the layer of a member and a gap 60. Note that FIG. 9 omits the illustration of heat transfer members such as the brazed portion 61. Further, FIG. 9 shows a part of the distribution direction DU of the first inner fin 33. In the second embodiment, the components having the same functions and functions as those in the first embodiment are designated by the same reference numerals, the description thereof will be omitted, and only the characteristic portions thereof will be described.

As shown in FIG. 9, the communication passage 200b connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200b is formed so as to diagonally connect the gap portions 60 in the combination of the gap portions 60 arranged alternately on the left and right in the distribution direction DU.

The passage width of the continuous passage 200b is smaller than the short dimension of the gap 60. Further, the flow path cross-sectional area of the communication passage 200b is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. In the plate heat exchanger 30, the gap portion 60 and the communication passage 200b are connected to form a discharge passage 200b1.

The discharge flow path 200b1 intersects the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged, with respect to the flow direction DU. It is formed so as to have an oblique TI located between the LR and the LR.

In the discharge flow path 200b1, in the flow direction DU of the first fluid, the closest front and rear gaps 60 among the plurality of gaps 60 are connected by the communication passage 200b, and the discharge flow path 200b1 is oblique between the flow direction DU and the intersection direction LR. It is formed so as to extend in the direction TI. Further, in the discharge flow path 200b1, the end portion of the discharge flow path 200b1 communicates with the outside of the main body 30A.

Further, in the heat medium flow path 38 as the first flow path through which the heat medium is circulated and the refrigerant flow path 39 as the second flow path through which the refrigerant is circulated, the flow of the first fluid and the second fluid in the flow direction DU. The road length is longer than the flow path width of the crossing direction LR.

According to the second embodiment, since the flow path length of the flow direction DU of the first fluid is always longer than the flow path width of the crossing direction LR, the discharge flow formed along the direction between them and communicates with the outside air. The path 200b1 is shorter than the discharge flow path 200a1 formed along the distribution direction DU. Therefore, in the discharge flow path 200b1, the distance from the damaged portion of the plate 32a to the outside air is short, and the flow path resistance of the leaking fluid can be reduced. Therefore, the plate heat exchanger 30 according to the second embodiment can secure a sufficient outflow flow rate of the leaked fluid to be detected externally.

FIG. 9 shows the upper corner of the first gap 60 in the left direction L and the second diagonally upward left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the right direction R is connected by a communication passage 200b. Further, FIG. 9 shows a third position located at the lower corner of the first gap 60 in the right direction R and diagonally lower right in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The upper corner of the gap portion 60 in the left direction L is connected by a communication passage 200b.

FIG. 10 is a plan view of the first inner fin 33 according to the first modification of the second embodiment, and is a perspective view when projected onto the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. Of these, only the layers of the heat transfer member and the gap 60 are shown. Note that FIG. 10 omits the illustration of heat transfer members such as the brazed portion 61. Further, FIG. 10 shows a part of the distribution direction DU of the first inner fin 33.

As shown in FIG. 10, the communication passage 200c connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200c is formed so as to connect the gaps 60 in the crossing direction LR in the combination of the gaps 60 arranged alternately on the left and right in the distribution direction DU. That is, the continuous passage 200c is formed so as to connect any two rows of the gaps 60 arranged in a staggered pattern in the crossing direction LR.

The passage width of the continuous passage 200c is smaller than the short size of the gap 60. Further, the flow path cross-sectional area of the continuous passage 200c is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. In the plate heat exchanger 30, the gap portion 60 and the communication passage 200c are connected to form a discharge passage 200c1. In the plate heat exchanger 30, the discharge flow path 200c1 formed by the plurality of gaps 60 and the communication passage 200 communicates with the outside of the main body 30A.

The discharge flow path 200c1 has a crossing direction LR whose passage direction intersects with the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged. It is formed to be.

Therefore, the plate heat exchanger 30 can further suppress the fluid resistance of the leaked fluid, prevent the mixing of the first fluid and the second fluid, and allow a sufficient amount of leaked fluid to flow out to the outside. be able to. Then, the heat transfer device 100 can stop the heat transfer device 100 by detecting the leaked fluid leaked from the plate heat exchanger 30, and can prevent damage to the air conditioner.

Note that FIG. 10 shows the upper corner of the first gap 60 in the left direction L and diagonally upward to the left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the right direction R of No. 2 is connected by a communication passage 200c. Further, FIG. 10 shows a third position located diagonally upward to the right in the flow direction of the first fluid and the upper corner of the right direction R of the first gap 60 when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the left direction L of No. 3 is connected by a communication passage 200c. The communication passage 200c is formed so as to connect the gaps 60 formed alternately in the upper and lower directions in the crossing direction LR intersecting the flow direction DU of the first fluid.

FIG. 11 is a plan view of the first inner fin 33 according to the second modification of the second embodiment, and is a perspective view when projected in the overlapping direction of the first heat transfer plate 32 and the second heat transfer plate 34. , Only the layers of the heat transfer member and the gap 60 are shown. Note that FIG. 11 omits the illustration of heat transfer members such as the brazed portion 61. Further, FIG. 11 shows a part of the distribution direction DU of the first inner fin 33.

As shown in FIG. 11, the communication passage 200a connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200a is formed so as to connect the gaps 60 formed in two rows adjacent to the crossing direction LR to the flow direction DU in the combination of the gaps 60 arranged alternately on the left and right in the flow direction DU. ing.

The communication passage 200a is formed in a straight line so as to extend in the distribution direction DU. In the plate heat exchanger 30, the gap portion 60 and the linearly formed communication passage 200a are connected to form the discharge passage 200a2. In the plate heat exchanger 30, the discharge flow path 200a2 formed by the plurality of gaps 60 and the communication passage 200 communicates with the outside of the main body 30A.

The discharge flow path 200a2 has a passage direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged, and the discharge flow path 200a2 has a discharge flow path 200a2. It is formed in a straight line.

Further, the discharge flow path 200a2 has a flow path direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged, and is also a discharge flow path. 200a2 is formed in a straight line. Therefore, in the plate heat exchanger 30, the passage resistance of the leaked fluid is further reduced, and a sufficient amount of leaked fluid flows out of the plate heat exchanger 30 to be detected outside the plate heat exchanger 30. Can be made to.

Embodiment 3.
FIG. 12 is a plan view of the first inner fin 33 according to the third embodiment, and is a perspective view of the first heat transfer plate 32 and the second heat transfer plate 34 projected onto the stacking direction FB. It is a figure which showed only the layer of a member and a gap 60. Note that FIG. 12 omits the illustration of heat transfer members such as the brazed portion 61. Further, FIG. 12 shows a part of the distribution direction DU of the first inner fin 33. In the third embodiment, the components having the same functions and functions as those of the first embodiment or the second embodiment are designated by the same reference numerals, the description thereof will be omitted, and only the characteristic portions thereof will be described.

As shown in FIG. 12, the communication passage 200d connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200d is formed so as to diagonally connect the gaps 60 arranged alternately on the left and right in the distribution direction DU.

The passage width of the continuous passage 200d is smaller than the short size of the gap 60. Further, the flow path cross-sectional area of the continuous passage 200d is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. In the plate heat exchanger 30, the gap portion 60 and the communication passage 200d are connected to form a discharge passage 200d1. In the plate heat exchanger 30, the discharge flow path 200d1 formed by the plurality of gaps 60 and the communication passage 200 communicates with the outside of the main body 30A.

The discharge flow path 200d1 intersects the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged, with respect to the flow direction DU. It is formed in any direction with the direction LR. Therefore, the plate heat exchanger 30 leaks in both the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path, and the crossing direction LR with respect to the flow direction DU. It is formed in a structure that can discharge fluid.

Further, in the heat medium flow path 38 as the first flow path for circulating the heat medium and the refrigerant flow path 39 as the second flow path for circulating the refrigerant, the flow paths in the flow directions DU of the first fluid and the second fluid. The length is longer than the flow path width of the crossing direction LR.

According to the third embodiment, the discharge flow path 200d1 has a flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path, and an intersection direction LR intersecting the flow direction DU. , It is formed in either direction. That is, the discharge flow path 200d1 is formed in the vertical and horizontal directions of the distribution direction DU and the crossing direction LR, and is formed in a grid pattern. Therefore, when the leaked fluid flows out from the inside of the plate heat exchanger 30 to the outside, the leaked fluid can flow out while being divided in a grid pattern from the gap 60 at the outflow start position. Therefore, the plate heat exchanger 30 can reduce the passage resistance of the leaked fluid, and can secure a sufficient outflow flow rate of the leaked fluid to be detected outside the plate heat exchanger 30.

Note that FIG. 12 shows the upper corner of the first gap 60 in the left direction L and diagonally upward to the left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the right direction R of No. 2 is connected by a continuous passage 200d. Further, when the flow direction of the first fluid is upward U, the lower corner of the first gap 60 in the left direction L and the third gap 60 located diagonally lower to the left in the flow direction of the first fluid. Shows a configuration in which the upper corner of the right direction R of the above is connected by a continuous passage 200d.

Further, FIG. 12 shows a second position located diagonally upward to the right in the flow direction of the first fluid and the upper corner of the right direction R of the first gap 60 when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the left direction L of No. 4 is connected by a communication passage 200d. Further, when the flow direction of the first fluid is upward U, the lower corner of the first gap 60 in the right direction R and the fifth gap 60 located diagonally lower to the right in the flow direction of the first fluid. The upper corner of the left direction L is connected by a continuous passage 200d.

FIG. 13 is a plan view of the first inner fin 33 according to the first modification in the third embodiment, and is a perspective view when projected in the overlapping direction of the first heat transfer plate 32 and the second heat transfer plate 34. , Only the layers of the heat transfer member and the gap 60 are shown. Note that FIG. 13 does not show the heat transfer member such as the brazed portion 61. Further, FIG. 13 shows a part of the distribution direction DU of the first inner fin 33.

The plate heat exchanger 30 has a continuous passage 200a and a continuous passage 200c. The communication passage 200a connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200a is formed so as to connect the gaps 60 arranged alternately on the left and right in the distribution direction DU.

The communication passage 200c connects the gaps 60 to each other so that the closest front and rear gaps 60 are connected by the shortest path in the flow direction DU of the first fluid. The communication passage 200c is formed so as to connect the gaps 60 in the crossing direction LR in the combination of the gaps 60 arranged alternately on the left and right in the distribution direction DU.

The passage width of the continuous passage 200a is smaller than the short size of the gap 60. Further, the flow path cross-sectional area of the communication passage 200a is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. Further, the passage width of the continuous passage 200c is configured to be smaller than the short dimension of the gap portion 60. Further, the flow path cross-sectional area of the continuous passage 200c is smaller than the flow path cross-sectional area of one of the gaps 60 among the plurality of gaps 60. In the plate heat exchanger 30, the gap 60 is connected to the communication passage 200a and the communication passage 200c to form a discharge passage 200e. In the plate heat exchanger 30, the discharge flow path 200e formed by the plurality of gaps 60 and the communication passage 200 communicates with the outside of the main body 30A.

The discharge flow path 200e intersects the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path in which the first inner fin 33 is arranged, with respect to the flow direction DU. It is formed in any direction with the direction LR. Therefore, the plate heat exchanger 30 leaks in both the flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path, and the crossing direction LR with respect to the flow direction DU. It is formed in a structure that can discharge fluid.

The discharge flow path 200e includes the number of passages formed in the distribution direction DU by connecting the gap portion 60 and the communication passage 200a, and the passage formed in the intersection direction LR by connecting the gap portion 60 and the communication passage 200c. Is different from the number of. In FIG. 13, the number of passages formed in the distribution direction DU by connecting the gap portion 60 and the communication passage 200a is the number of passages formed in the intersection direction LR by connecting the gap portion 60 and the communication passage 200c. More than. In the discharge flow path 200e, the number of passages formed in the distribution direction DU by connecting the gap portion 60 and the communication passage 200a is formed in the intersection direction LR by connecting the gap portion 60 and the communication passage 200c. It is not limited to a configuration that is larger than the number of passages.

According to the third embodiment, the discharge flow path 200e has a flow direction DU of the first fluid flowing through the heat medium flow path 38, which is the first flow path, and an intersection direction LR intersecting the flow direction DU. , A flow path is formed in either direction. That is, the discharge flow path 200e is formed in the vertical and horizontal directions of the distribution direction DU and the crossing direction LR, and is formed in a grid pattern. Further, in the discharge flow path 200e, the length of the flow path formed in the flow direction DU which is the flow direction of the first fluid and the second fluid is the length of the flow path formed in the intersection direction LR intersecting the flow direction DU. Longer than the length. Therefore, the flow path formed in the flow direction DU has a longer flow path length and a larger fluid resistance than the flow path formed in the crossing direction LR.

As described above, in the discharge flow path 200e shown in FIG. 13, the number of passages formed by connecting the gap portion 60 and the communication passage 200a in the distribution direction DU connects the gap portion 60 and the communication passage 200c. There are more passages formed in the crossing direction LR. That is, the plate heat exchanger 30 is formed so that the number of flow paths in the flow direction DU, which has a larger fluid resistance than the flow paths in the cross direction LR, is larger than the number of flow paths in the cross direction LR. ..

The plate heat exchanger 30 is formed so that the number of flow paths in the flow direction DU is larger than the number of flow paths in the crossing direction LR, so that the plate heat exchanger 30 is detected outside the plate heat exchanger 30. It can be configured with the minimum number of passages required to ensure a sufficient outflow of leaked fluid. Therefore, the plate heat exchanger 30 can suppress a decrease in the area ratio of the brazed portion 61 due to the formation of the discharge flow path 200e, and by extension, a plate type heat exchanger based on the decrease in the area ratio of the brazed portion 61. It is possible to suppress the performance deterioration of 30.

Note that FIG. 13 shows the upper corner of the first gap 60 in the left direction L and diagonally upward to the left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The lower corner of the gap 60 in the right direction R of No. 2 is connected by a communication passage 200a. Further, FIG. 6 shows a third position located at the lower corner of the first gap 60 in the left direction L and diagonally lower left in the flow direction of the first fluid when the flow direction of the first fluid is the upward direction U. The upper corner of the gap portion 60 in the right direction R is connected by a communication passage 200a. The communication passage 200a is formed so as to connect the gaps 60 formed alternately on the left and right in the flow direction DU of the first fluid.

In FIG. 13, some of the gaps 60 among the plurality of gaps 60 are connected to each other by the communication passage 200c as described below. When the flow direction of the first fluid is upward U, the upper corner of the left direction L of the first gap 60 and the second gap 60 located diagonally upward to the left in the flow direction of the first fluid. The lower corner of the right direction R is connected by a connecting passage 200c. Further, when the flow direction of the first fluid is upward U, the upper corner of the right direction R of the first gap 60 and the third gap located diagonally upward to the right in the flow direction of the first fluid. The lower corner of the left direction L of 60 is connected by a continuous passage 200c. The communication passage 200c is formed so as to connect the gaps 60 formed alternately in the upper and lower directions in the crossing direction LR intersecting the flow direction DU of the first fluid.

Embodiment 4.
FIG. 14 is an explanatory view showing a cross-sectional view of the plate heat exchanger 30 according to the fourth embodiment. In the fourth embodiment, the components having the same functions and functions as those of the first embodiment, the second embodiment or the third embodiment are designated by the same reference numerals and the description thereof is omitted, and only the characteristic portions thereof are omitted. Will be explained.

As shown in FIG. 14, of the first heat transfer plate 32 and the second heat transfer plate 34, only the first heat transfer plate 32 is a double wall in which two metal plates of the plate 32a and the plate 32b are overlapped. It is configured in.

Further, in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the length of the first inner fin 33 is substantially the same as the length of the second inner fin 35. That is, in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34, the length of the orthogonal portion 41 of the first inner fin 33 is substantially the same as the length of the orthogonal portion 51 of the second inner fin 35. The length.

According to the fourth embodiment, when the brazing portion 61 is projected in the overlapping direction of the first heat transfer plate 32 and the second heat transfer plate 34, the brazing portion 61 exists in the region of the second pitch 40b. do not. According to this configuration, the second pitch 40b has a wider pitch than the first pitch 40a, and the position of the second pitch 40b faces the gap 60 via the plate 32a of the first heat transfer plate 32. Can be configured at the desired position. Therefore, even if a factor that damages the plate heat exchanger 30 should occur, the plate 32a of the first heat transfer plate 32 faces the second pitch 40b rather than the position facing the first pitch 40a. The position where you are is easily damaged.

In the fourth embodiment, the plate heat exchanger 30 has a double wall structure only in the first heat transfer plate 32. Therefore, the plate heat exchanger 30 has a function that the plate 32a at the position facing the second pitch 40b is easily damaged in comparison with the plate 32a at the position facing the first pitch 40a, and heat is generated. The resistance can be further suppressed and the heat exchange performance can be improved.

In order to make the portion of the plate 32a between the second pitch 40b and the gap 60 more vulnerable than the plate 32b and the second heat transfer plate 34, the plate thickness of the plate 32a is set to the plate 32b and the second heat transfer plate 34. It is desirable to make it smaller than the plate thickness of.

Further, in the fourth embodiment, the length of the second inner fin 35 is the same as the length of the first inner fin 33 in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. However, in the plate type heat exchanger 30, the larger the length of the second inner fin 35, the larger the surface area of the second inner fin 35, and the heat exchange performance can be improved. Therefore, in the plate heat exchanger 30, the length of the second inner fin 35 is made larger than the length of the first inner fin 33 in the stacking direction FB of the first heat transfer plate 32 and the second heat transfer plate 34. You may. Even in this case, the plate heat exchanger 30 has a great influence on the function that the plate 32a at the position facing the second pitch 40b is easily damaged in comparison with the plate 32a at the position facing the first pitch 40a. I will not give it.

The heat transfer device 100 described above includes the plate heat exchanger 30 according to any one of the first to fourth embodiments. Therefore, in the heat transfer device 100, the same effect as that of any one of the first to fourth embodiments can be obtained.

Each of the above embodiments 1 to 4 can be implemented in combination with each other. Further, the configuration shown in the above embodiment is an example, and can be combined with another known technique, and a part of the configuration is omitted or changed without departing from the gist. It is also possible.

10 Refrigerant circuit, 11 Outdoor unit, 12 Compressor, 13 Flow path switching device, 14 Decompression device, 15 Outdoor heat exchanger, 16 Refrigerant piping, 20 Heat medium circuit, 21 House, 22 Circulation pump, 23 Radiator, 24 Heat medium Piping, 25 indoor unit, 30 plate type heat exchanger, 30A main body, 31 side plate, 31a heat medium inlet, 31a1 heat medium outward path hole, 31a2 heat medium outward path hole, 31b heat medium outlet, 31b1 heat medium return path hole, 31b2 heat Medium return hole, 31c refrigerant inlet, 31c1 refrigerant outbound hole, 31c2 refrigerant outbound hole, 31d refrigerant outlet, 31d1 refrigerant return hole, 31d2 refrigerant return hole, 32 first heat transfer plate, 32a plate, 32b plate, 33 first inner fin , 34 2nd heat transfer plate, 34a plate, 34b plate, 35 2nd inner fin, 38 heat medium flow path, 39 refrigerant flow path, 40 uneven pitch, 40a 1st pitch, 40b 2nd pitch, 40b1 flat surface, 40b2 Opening, 40c1 top, 40c2 bottom, 41 orthogonal part, 50 uneven pitch, 50c1 top, 50c2 bottom, 51 orthogonal part, 60 voids, 61 brazing part, 100 heat transfer device, 101 compressor, 200 communication passage, 200a Continuous passage, 200a1 discharge flow path, 200a2 discharge flow path, 200b continuous passage, 200b1 discharge flow path, 200c continuous passage, 200c1 discharge flow path, 200d continuous passage, 200d1 discharge flow path, 200e discharge flow path.

Claims

A plurality of heat transfer plates are laminated, and a first flow path through which the first fluid flows and a second flow path through which the second fluid flows are alternately formed with each heat transfer plate of the plurality of heat transfer plates as a boundary. Equipped with a body that is
The main body
Among the plurality of heat transfer plates, the first flow path is formed between the first heat transfer plate and the second heat transfer plate arranged so as to face each other.
The first flow path has a plate-shaped inner fin in which a plurality of concave-convex bent portions are formed.
The first heat transfer plate is
Two plates facing each other and
A plurality of brazing portions provided between the two plates and connecting the two plates, and
Have,
In the first heat transfer plate,
A plurality of voids, which are spaces formed by the two plates and the plurality of brazed portions,
A continuous passage connecting the gaps of the plurality of gaps and
Is formed,
The inner fin
A plurality of uneven pitches formed in an uneven shape in the cross section of the inner fin perpendicular to the flow direction of the first fluid are provided in the flow direction.
At least one or more of the uneven pitches
The first pitch that comes into contact with the first heat transfer plate and the second heat transfer plate, and
A second pitch that is in contact with the second heat transfer plate and is larger than the first pitch in the intersecting direction perpendicular to the stacking direction and the distribution direction of the plurality of heat transfer plates.
Have,
When the inside of the main body is projected in the stacking direction, the plurality of voids are formed in the region of the second pitch, and the discharge flow formed by the plurality of voids and the communication passage. A plate heat exchanger in which the path communicates with the outside of the main body.
The plate heat exchanger according to claim 1, wherein the plurality of gaps are not formed in the region of the first pitch when the inside of the main body is projected in the stacking direction.
The plate heat exchanger according to claim 1 or 2, wherein the second pitch is provided at least one in one pitch with at least one or more of the first pitch in the crossing direction.
The inner fin
In the distribution direction, the first uneven pitch having the first pitch and the second pitch and the second uneven pitch having the first pitch and the second pitch are between the first uneven pitch. The plate heat exchanger according to any one of claims 1 to 3, which has a third uneven pitch having only one pitch.
The discharge channel is
In the flow direction of the first fluid, the closest front and rear gaps among the plurality of gaps are connected by the communication passage and formed so as to extend in the flow direction, and the end of the discharge flow path. The plate heat exchanger according to any one of claims 1 to 4, wherein the unit communicates with the outside of the main body.
The discharge channel is
In the flow direction of the first fluid, the closest front and rear gaps among the plurality of gaps are connected by the communication passage and formed so as to extend in an oblique direction between the flow direction and the intersection direction. The plate heat exchanger according to any one of claims 1 to 4, wherein the end portion of the discharge flow path communicates with the outside of the main body.
The discharge channel is
In the flow direction of the first fluid, the closest front and rear gaps among the plurality of gaps are connected by the communication passage and formed so as to extend in the crossing direction, and the end of the discharge flow path. The plate heat exchanger according to any one of claims 1 to 4, wherein the unit communicates with the outside of the main body.
The discharge channel is
In the flow direction of the first fluid, the closest front and rear gaps among the plurality of gaps are connected by the communication passage and are formed so as to extend in the flow direction and the intersection direction. The plate heat exchanger according to any one of claims 1 to 4, wherein the end of the discharge flow path communicates with the outside of the main body.
The discharge channel is
In the flow direction of the first fluid, the closest front and rear gaps among the plurality of gaps are connected by the communication passage and are formed so as to extend in the flow direction and the intersection direction. The end of the discharge flow path communicates with the outside of the main body,
The plate heat exchanger according to any one of claims 1 to 4, wherein the number of passages formed in the flow direction is larger than the number of passages formed in the intersection direction.
The plate heat exchanger according to any one of claims 1 to 9, wherein the flow path cross-sectional area of the communication passage is smaller than the flow path cross-sectional area of one of the plurality of voids.
The plate heat exchanger according to any one of claims 1 to 10, wherein the first fluid is water or brine.
The plate heat exchanger according to any one of claims 1 to 11, wherein the second fluid flowing through the second flow path is a refrigerant.
A heat transfer device provided with the plate heat exchanger according to any one of claims 1 to 12.