CN109564067B

CN109564067B - Heat exchanger and refrigeration system using the same

Info

Publication number: CN109564067B
Application number: CN201780047793.4A
Authority: CN
Inventors: 奥村拓也; 山本宪昭; 名越健二; 大城崇裕
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2016-10-21
Filing date: 2017-10-13
Publication date: 2020-06-23
Anticipated expiration: 2037-10-13
Also published as: JP2018066536A; MY195134A; WO2018074348A1; CN109564067A; JP6785409B2

Abstract

The heat exchanger of the present invention includes a plate fin laminate body in which a plurality of plate fins are laminated, a 1 st end plate and a 2 nd end plate, a 1 st inlet connection pipe, a 1 st outlet connection pipe, a 2 nd inlet connection pipe, and a 2 nd outlet connection pipe, and a 2 nd fluid flows between the plate fin laminate bodies. Heat is exchanged between the 1 st fluid and the 2 nd fluid. The inner diameter of the inlet-side header flow path is smaller than the inner diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe. The inner diameter of the outlet-side header flow path is smaller than the inner diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe.

Description

Heat exchanger and refrigeration system using the same

Technical Field

The present invention relates to a heat exchanger and a refrigeration system using the same. The present invention particularly relates to a plate-fin stacked heat exchanger configured by stacking plate-like plate fins through which a refrigerant flows, and a refrigeration system using the same.

Background

In general, a refrigeration system such as an air conditioner or a refrigerator performs cooling or heating by circulating a refrigerant compressed by a compressor through a heat exchanger such as a condenser or an evaporator and performing heat exchange with a fluid to be heat-exchanged. In this refrigeration system, the performance and energy saving performance of the system are greatly influenced by the heat exchange efficiency of the heat exchanger. Therefore, the heat exchanger is strongly required to have high efficiency.

Among these, a fin-tube type heat exchanger in which a fin group penetrates a heat transfer tube is generally used as a heat exchanger of a refrigeration system. Accordingly, the heat transfer pipe can be reduced in diameter to improve heat exchange efficiency and reduce the size of the heat transfer pipe.

However, since there is a limit to the reduction in the diameter of the heat transfer pipe, the improvement in heat exchange efficiency and the reduction in size are becoming more and more limited.

On the other hand, as a heat exchanger for exchanging heat energy, a plate fin stacked type heat exchanger in which plate fins having fluid flow passages are stacked is known.

The plate-fin stacked heat exchanger exchanges heat between a 1 st fluid flowing through flow passages formed in the plate fins and a 2 nd fluid, which is a fluid to be heat exchanged, flowing between the stacked plate fins. Therefore, the present invention is widely used in an air conditioner for a vehicle (see patent document 1).

Fig. 33 and 34 show the plate-fin stacked heat exchanger described in patent document 1. In the heat exchanger 100, the plate fins 102 having the flow passages 101 through which the 1 st fluid flows are stacked to form a plate fin stacked body 103. End plates 104 are laminated on both side portions of the plate-fin laminated body 103.

Documents of the prior art

Patent document

Patent document 1: utility model registration No. 3192719

Disclosure of Invention

The plate-fin stacked heat exchanger described in patent document 1 has an advantage that the cross-sectional area of the flow path 101 can be made smaller than that of the fin-tube type heat transfer tubes because the flow path 101 is formed by press-forming concave grooves in the plate fins 102.

However, the area of the header flow path 105 through which the refrigerant flows in each flow path 101 is extremely larger than the area of each flow path 101, and therefore the pressure of the refrigerant in the header flow path 105 portion becomes large. This causes a problem that the portion of the end plate 102 having the header flow path 105 (the upper and lower portions of the plate-fin stacked heat exchanger indicated by X in fig. 33 and 34) expands and deforms outward.

In the case of a heat exchanger of an automobile air conditioner, the amount of refrigerant is small and the refrigerant pressure is not so high, and therefore, the expansion deformation at the header flow path 105 portion is suppressed by the rigidity of the end plate 104. Therefore, it is not identified as a problem.

However, according to the experiments of the inventors, in the case of a heat exchanger having a larger amount of refrigerant than an automobile air conditioner, such as a home air conditioner and a business air conditioner, the pressure of expansion deformation at the header flow path 105 portion is very large compared to the automobile air conditioner, and it is difficult to suppress the expansion deformation at the header flow path 105 portion. Further, it was found that there was a problem that the end plate 104 expanded and deformed outward depending on the circumstances.

Further, it has been found that the dimension of the plate fin 102 in the stacking direction is limited due to the expansion and deformation, and it is difficult to use the plate fin as a heat exchanger having a width dimension suitable for use in a household air conditioner, a business air conditioner, and the like.

In addition, from the viewpoint of preventing global warming, recent air conditioners are under study for practical use of R1123(1,1, 2-trifluoroethylene) and R1132(1, 2-difluoroethylene) refrigerants having a small Global Warming Potential (GWP). Since these refrigerants have higher pressures than the conventional R410A refrigerant, it is assumed that when such a refrigerant is used, expansion deformation at the header flow path 105 portion becomes remarkable. Thus, some expansion deformation suppression measures must be taken.

The present invention has been made in view of the above-described problems occurring in the conventional findings and environmental measures, and can suppress the expansion deformation of the header flow path portion even in a heat exchanger used for a household or a business air conditioner or the like. Thus, a heat exchanger having high heat exchange efficiency and a high-performance refrigeration system using the same can be provided.

In order to achieve the above object, a heat exchanger of the present invention includes: a plate fin laminate body configured by laminating a plurality of plate fins each having a flow path through which a 1 st fluid flows; a 1 st end plate and a 2 nd end plate respectively arranged at both ends of the plate-fin stacked body in the stacking direction; a 1 st inlet connection pipe connected to the 1 st end plate and into which the 1 st fluid flows; a 1 st outlet connection pipe connected to the 1 st end plate and through which the 1 st fluid flows out; a 2 nd inlet connection pipe connected to the 2 nd end plate and communicated with the 1 st inlet connection pipe; and a 2 nd outlet connection pipe connected to the 2 nd end plate and communicated with the 1 st outlet connection pipe. A 2 nd fluid flows between the plate fin stacked layers of the plate fin stacked body, and heat is exchanged between the 1 st fluid and the 2 nd fluid. Each of the plurality of plate fins includes a flow path region having a plurality of 1 st fluid flow paths through which the 1 st fluid flows, and a header region having a header flow path communicating with the plurality of 1 st fluid flow paths. The header flow path includes an inlet-side header flow path communicating the 1 st inlet connection pipe and the 2 nd inlet connection pipe, and an outlet-side header flow path communicating the 1 st outlet connection pipe and the 2 nd outlet connection pipe. The 1 st fluid flow path is formed by concave grooves provided in the plurality of plate fins, respectively. The inner diameter of the inlet-side header flow path is smaller than the inner diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe. The outlet-side manifold channel has an inner diameter smaller than the inner diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe. Here, the inner diameter of the header flow path refers to the inner diameter of the largest portion of the diameters of the header flow path.

At the header area corresponding portion of the 1 st end plate, the 1 st fluid pressure from the header flow path side and the 1 st fluid pressure from the 1 st inlet connection pipe and the 1 st outlet connection pipe side are applied. Also, at the header area corresponding portion of the 2 nd end plate, the 1 st fluid pressure from the header flow path side and the 1 st fluid pressure from the 2 nd inlet connection pipe and the 2 nd outlet connection pipe side are applied. In the present invention, the inner diameter of the inlet-side header flow path is smaller than the inner diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe. Further, the inner diameter of the outlet-side header flow path is smaller than the inner diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe. Therefore, the 1 st fluid pressure from the 1 st inlet connection pipe and the 1 st outlet connection pipe side is larger than the 1 st fluid pressure from the header flow path side, and the influence of the 1 st fluid pressure from the header flow path side can be cancelled out. Similarly, the 1 st fluid pressure from the 2 nd inlet connection pipe and the 2 nd outlet connection pipe side is greater than the 1 st fluid pressure from the header flow path side, and the influence of the 1 st fluid pressure from the header flow path side can be cancelled out. Thereby, the outward expansion deformation of the header region corresponding portion can be suppressed. Therefore, the heat exchange efficiency of the heat exchanger can be further improved by reducing the diameter of the 1 st fluid flow passage while suppressing such expansion deformation. Thereby providing a high-performance refrigerating system which is small in size and high in energy saving performance.

According to the above configuration, the present invention can suppress expansion deformation of the header region portion even in a heat exchanger used for a household air conditioner, a business air conditioner, or the like. Thus, a small and efficient heat exchanger and a refrigeration system using the same with high energy saving performance can be provided.

Drawings

Fig. 1 is a perspective view showing the appearance of a plate-fin stacked heat exchanger according to embodiment 1 of the present invention.

Fig. 2 is a sectional view a-a of fig. 1.

Fig. 3 is an external perspective view showing a plate-fin stacked body of the plate-fin stacked heat exchanger according to embodiment 1.

Fig. 4 is an exploded perspective view showing the plate-fin stacked body in a vertically separated state.

Fig. 5 is an exploded perspective view of the plate-fin laminate.

Fig. 6 is a side view showing a stacked state of the plate fin stacked body.

Fig. 7 is a schematic view showing a section B-B of fig. 3.

Fig. 8 is a schematic view showing a cross section C-C of fig. 3.

Fig. 9 is a schematic view showing an enlarged section a-a of fig. 1.

Fig. 10 is a perspective view showing a connection portion of each connection pipe at the inlet and the outlet of the plate-fin stacked body according to embodiment 1 of the present invention and a header opening portion in a cut-off manner.

Fig. 11 is a perspective view showing a refrigerant flow path group portion of the plate-fin stacked body of the plate-fin stacked heat exchanger in a cut-off manner.

Fig. 12 is a perspective view showing the plate-fin stacked heat exchanger with the refrigerant flow path group partially cut off.

Fig. 13 is a perspective view showing the plate-fin stacked body of the plate-fin stacked heat exchanger in a position partially cut off by boss holes.

Fig. 14 is a perspective view showing a header opening portion of the plate-fin stacked body of the plate-fin stacked heat exchanger in a truncated state.

Fig. 15 is a plan view of a plate fin constituting the plate fin stacked body of the plate fin stacked type heat exchanger.

Fig. 16 is an enlarged plan view showing a header region of the plate fin.

Fig. 17 is an exploded view showing the structure of the plate fin in an enlarged manner.

Fig. 18A is a plan view of the 1 st plate fin.

Fig. 18B is a top view of the 2 nd plate fin.

Fig. 18C is a plan view for explaining a state where the 1 st and 2 nd fin plates are overlapped.

Fig. 19 is a diagram for explaining the refrigerant flow operation of the plate fin.

Fig. 20 is an enlarged perspective view showing a protrusion provided in the flow path region of the plate fin.

Fig. 21 is an enlarged perspective view showing a projection provided at a U-turn side end portion of the refrigerant flow path of the plate fin.

Fig. 22 is a perspective view showing the appearance of a plate-fin stacked body of the plate-fin stacked heat exchanger according to embodiment 2 of the present invention.

Fig. 23 is a plan view showing the plate fins constituting the plate fin laminate.

Fig. 24 is an exploded view showing an enlarged structure of a plate fin of the plate fin stacked heat exchanger.

Fig. 25 is a perspective view showing a refrigerant flow path group portion of the plate-fin stacked body of the plate-fin stacked heat exchanger in a cut-off manner.

Fig. 26 is a perspective view showing the appearance of a plate-fin laminate of the plate-fin laminated heat exchanger according to embodiment 3 of the present invention.

Fig. 27 is a perspective view showing a state in which the flow distribution control tubes are removed from the plate-fin stacked body.

Fig. 28 is a perspective view showing a flow distribution control tube insertion portion of the plate fin laminate.

Fig. 29 is a perspective view of the flow distribution control tube of the plate fin stacked type heat exchanger.

Fig. 30 is a schematic cross-sectional view showing a flow dividing control tube portion of the plate fin stacked heat exchanger.

Fig. 31 is a refrigeration cycle diagram of an air conditioner using the fin-plate stacked heat exchanger of the present invention.

Fig. 32 is a schematic cross-sectional view of the air conditioner.

Fig. 33 is a schematic cross-sectional view of a conventional plate-fin stacked heat exchanger.

Fig. 34 is a plan view of the plate fins of the conventional plate fin laminated heat exchanger.

Detailed Description

The heat exchanger of the invention 1 comprises: a plate fin laminate body configured by laminating a plurality of plate fins each having a flow path through which a 1 st fluid flows; a 1 st end plate and a 2 nd end plate respectively arranged at both ends of the plate-fin stacked body in the stacking direction; a 1 st inlet connection pipe connected to the 1 st end plate and into which the 1 st fluid flows; a 1 st outlet connection pipe connected to the 1 st end plate and through which the 1 st fluid flows out; a 2 nd inlet connection pipe connected to the 2 nd end plate and communicated with the 1 st inlet connection pipe; and a 2 nd outlet connection pipe connected to the 2 nd end plate and communicated with the 1 st outlet connection pipe. A 2 nd fluid flows between the plate fin stacked layers of the plate fin stacked body, and heat is exchanged between the 1 st fluid and the 2 nd fluid. Each of the plurality of plate fins includes a flow path region having a plurality of 1 st fluid flow paths through which the 1 st fluid flows, and a header region having a header flow path communicating with the plurality of 1 st fluid flow paths. The header flow path includes an inlet-side header flow path communicating the 1 st inlet connection pipe and the 2 nd inlet connection pipe, and an outlet-side header flow path communicating the 1 st outlet connection pipe and the 2 nd outlet connection pipe. The 1 st fluid flow path is formed by concave grooves provided in the plurality of plate fins, respectively. The inner diameter of the inlet-side header flow path is smaller than the inner diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe. The outlet-side manifold channel has an inner diameter smaller than the inner diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe. Here, the inner diameter of the header flow path refers to the inner diameter of the largest portion of the diameters of the header flow path.

In the 2 nd invention, the inner diameter of the inlet-side header flow path is smaller than the outer diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe. The inner diameter of the outlet-side header flow path is smaller than the outer diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe.

This allows the pipe wall of the connection pipe to receive the refrigerant pressure from the header flow path.

In the 3 rd aspect of the present invention, each of the 1 st fluid flow paths is formed in a U-shape. The inlet-side header flow passage and the outlet-side header flow passage are disposed on one end side of each of the plurality of plate fins. The inlet opening and the outlet opening of the inlet-side header flow path are respectively communicated with the 1 st inlet connection pipe and the 2 nd inlet connection pipe. The inlet opening and the outlet opening of the outlet-side header flow path are respectively communicated with a 1 st outlet connection pipe and a 2 nd outlet connection pipe.

Thus, the heat exchange amount of the refrigerant can be increased by extending the 1 st fluid flow path without increasing the plate fin (making the plate fin long), and the heat exchange efficiency can be further improved. And miniaturization can be advanced. Further, since the inlet-side header flow path and the outlet-side header flow path are concentrated on one end side of the plate fin, even if the 1 st fluid flow amount in the header region portion increases and the pressure of the 1 st fluid flow path increases, the above-described pressure cancellation effect can be utilized to reliably prevent the expansion deformation in the header region corresponding portion.

In the 4 th aspect of the present invention, a flow dividing control tube inserted into the header flow path is connected to an inlet opening of the 1 st end plate. The 1 st end plate is formed of a material such that a potential difference between the flow dividing control tube and the 1 st inlet connection tube or a potential difference between the flow dividing control tube and the 1 st outlet connection tube is smaller than a potential difference when the flow dividing control tube and the 1 st inlet connection tube are directly connected or the flow dividing control tube and the 1 st outlet connection tube are directly connected.

This can prevent contact corrosion of different metals which occurs when the flow dividing control pipe and the inflow/outflow pipe are directly connected, and can greatly improve the reliability in long-term use.

In the 5 th aspect, the present invention provides a plurality of the plate-fin stacked body. The plate fin laminate is connected to each other by the 2 nd inlet connection pipe and the 2 nd outlet connection pipe.

This makes it possible to increase the dimension width of the entire heat exchanger in the plate-fin stacking direction, and to realize a long heat exchanger suitable for home air conditioners, business air conditioners, and the like while suppressing expansion deformation.

The 6 th aspect of the present invention is a refrigeration system including the heat exchanger.

Thus, the refrigeration system is provided with a heat exchanger which suppresses expansion deformation in the header region portion and is small and efficient. Therefore, a high-performance refrigeration system with high energy saving performance can be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The heat exchanger according to the present invention is not limited to the structure of the plate-fin stacked heat exchanger described in the following embodiments, and includes a structure of a heat exchanger equivalent to the technical idea described in the following embodiments.

The embodiments described below are merely examples of the present invention, and the structures, functions, operations, and the like described in the embodiments are merely examples and do not limit the present invention.

(embodiment mode 1)

Fig. 1 is a perspective view showing an appearance of a plate-fin stacked heat exchanger (hereinafter, simply referred to as a heat exchanger) 1 according to the present embodiment. Fig. 2 is a sectional view a-a of fig. 1. Fig. 3 is an external perspective view showing a plate-fin stacked body of the plate-fin stacked heat exchanger according to embodiment 1. Fig. 4 is an exploded perspective view showing the plate-fin stacked body in a vertically separated state. Fig. 5 is an exploded perspective view of the plate-fin laminate. Fig. 6 is a side view showing a stacked state of the plate fin stacked body.

As shown in fig. 1, a heat exchanger 1 according to the present embodiment is configured by connecting a plurality of plate fin laminates 2.

As shown in fig. 3 and 4, the plate fin laminate 2 is configured by laminating a plurality of plate fins 2a having a refrigerant flow path group (the refrigerant flow path structure of the plate fins 2a including the refrigerant flow path group will be described later) through which a refrigerant as a 1 st fluid flows between a 1 st end plate 3a and a 2 nd end plate 3 b. When the heat exchanger is used as a condenser in the 1 st end plate 3a and the 2 nd end plate 3b, an inlet connection pipe 4 into which a refrigerant flows is connected and fixed to an outlet connection pipe 5 which discharges the refrigerant flowing through the flow path in the plate fin 2 a.

The refrigerant flow path group of the refrigerant in the flow plate fin 2a is formed in a U shape (including a substantially U shape). An inlet connection pipe 4 and an outlet connection pipe 5 connected to the refrigerant flow path group are collectively arranged on one end side of the plate fin laminated body 2.

The inlet connection pipe 4 and the outlet connection pipe 5 are not provided in the 2 nd end plate 3b of the plate fin laminated body 2 (the lowermost plate fin laminated body 2 shown in fig. 1) which is the endmost in the flow direction of the refrigerant, and are in a closed state.

The 1 st and 2

nd end plates

3a and 3b provided on both sides (upper and lower sides in fig. 1) in the stacking direction of the plate fin laminate 2 and having substantially the same shape as the plate fins 2a in a plan view are formed of a rigid plate material, and are formed by, for example, grinding a metal material such as aluminum, an aluminum alloy, or stainless steel.

The plate fin laminate 2, the 1 st end plate 3a, and the 2 nd end plate 3b are integrally formed by brazing in a laminated state. They may also be joined using other fixing methods having heat resistance, such as chemical joining members.

As shown in fig. 3 and 5, reinforcing

plates

16a and 16b are disposed on the outer surfaces of the header region corresponding portions of the 1 st end plate 3a and the 2 nd end plate 3b disposed on both sides of the plate fin laminate 2. Here, the "header region corresponding portion" refers to a portion of the 1 st and 2 nd end plates (predetermined region of the end plate) that overlaps the header region H (see fig. 15) of the plate fin 2a when the 1 st and 2

nd end plates

3a and 3b are overlapped with the plate fin 2 a. The reinforcing

plates

16a and 16b are connected and fixed by a connecting portion 9 such as a bolt, a nut, or a rivet shaft penetrating the plate-fin stacked body 2. That is, the 1 st end plate 3a and the 2 nd end plate 3b on both sides of the plate fin laminate 2 mechanically connect and fix the plate fin laminate 2 with the plate fin laminate 2 interposed therebetween.

The reinforcing

plates

16a and 16b are made of a rigid plate material, for example, a metal material such as stainless steel or aluminum alloy, as in the

end plates

3a and 3 b.

As shown in fig. 1, a plurality of plate-fin stacked bodies 2 configured as described above are connected to one another by inlet connection pipes 4 and outlet connection pipes 5. Thereby, the heat exchanger is constituted. The refrigerant flowing from the inlet connection pipe 4 of the uppermost plate fin stacked body 2 flows to the other plate fin stacked body 2 connected to each other. The refrigerant returned from the other plate fin laminated bodies 2 to the uppermost plate fin laminated body 2 is discharged from the outlet connection pipe 5 to the outside of the heat exchanger 1. Here, in each plate-fin laminate, the refrigerant flows in parallel in the longitudinal direction through the flow path groups in the respective plate fins 2a, turns around in a U-turn, and turns back. On the other hand, air as the 2 nd fluid passes through gaps formed between the stacked layers of the plate fins 2a constituting each plate fin stacked body 2. Thereby, heat exchange between the refrigerant as the 1 st fluid and the air as the 2 nd fluid is performed.

Next, the plate fins 2a constituting the plate fin laminate 2 will be described, and the plate fin laminate 2 constitutes the main body of the heat exchanger 1.

Fig. 7 to 14 are perspective views showing a plate fin laminate 2 partially cut away. Fig. 15 to 21 are views showing the structure of the plate fin 2 a.

As shown in fig. 11, the plate fin laminate 2 is configured by stacking plate fins 2a (1

st plate fin

6, 2 nd plate fin 7) having 2 kinds of flow path structures.

As shown in fig. 17, the 1 st plate fin 6 and the 2 nd plate fin 7 of the plate fin 2a are each formed by brazing a 1 st plate-like member 6a, which is press-formed with a refrigerant flow path structure described later, to a 2 nd plate-like member 6b having the same structure as the 1 st plate-like member 6a in a face-to-face manner. The 1 st plate-like member 6a and the 2 nd plate-like member 6b have concave grooves, respectively, and the 1 st plate-like member 6a and the 2 nd plate-like member 6b are fixed to each other to constitute a refrigerant flow path. The 1 st plate-like member 6a and the 2 nd plate-like member 6b are formed of rectangular thin metal plates such as aluminum, aluminum alloy, and stainless steel.

The flow path structure formed in the plate fin 2a will be described below.

The 1 st plate fins 6 and the 2 nd plate fins 7 of the plate fin 2a have the same configuration except for the position shift of the refrigerant flow paths 11 described later, and therefore the case of the 1 st plate fins 6 will be described by way of illustration in fig. 15 to 17.

As shown in fig. 15, the plate fin 2a (6, 7) has a header region H formed at one end (left side in fig. 15) in the longitudinal direction, and the other region serves as a flow path region P. In the header region H, an inflow-side header opening 8a and an outlet-side header opening 8b are formed. The inlet connection pipe 4 and the outlet connection pipe 5 are communicated with the inflow-side header opening 8a and the outlet-side header opening 8b, respectively.

In addition, the flow path region P is formed with a plurality of 1 st fluid flow paths (hereinafter, referred to as refrigerant flow paths) 11 through which the refrigerant as the 1 st fluid flows from the header opening 8a in parallel. The group of refrigerant flow paths 11 is folded back at the other end portions (near the right end portions in fig. 15) of the plate fins 2a (6, 7) and connected to the outlet-side header opening 8 b. Specifically, the refrigerant flow path 11 group is composed of a forward flow path portion 11a connected to the inflow side header opening 8a and a return flow path portion 11b connected to the outlet side header opening 8b, and is formed in a substantially U-folded shape. The refrigerant flowing from the inflow side header opening 8a flows from the outward flow path portion 11a to the return flow path portion 11b U while turning around and flows to the outlet side header opening 8 b.

Further, around the inflow-side header opening 8a, as shown enlarged in fig. 16, a header flow path 10 is formed in which the refrigerant from the header opening 8a flows to the group of refrigerant flow paths 11. The header flow path 10 includes an outer peripheral flow path 10a formed so as to bulge from the outer periphery of the header opening 8a, one connection flow path 10b extending toward the refrigerant flow path 11 group side of the outer peripheral flow path 10a, and a multi-branch flow path 10c connecting the connection flow path 10b and each flow path of the refrigerant flow path 11 group.

The outer peripheral flow path 10a, the connection flow path 10b, and the multi-branch flow path 10c of the header flow path 10 are formed wider than the refrigerant flow paths 11 arranged in parallel in the flow path region P. In the header flow passage 10, a vertical cross-sectional shape orthogonal to the flow direction is a rectangular shape.

The opening diameter of the inflow-side header opening 8a is larger than the opening diameter of the outlet-side header opening 8 b. This is because, when the heat exchanger is used as a condenser, the volume of the refrigerant after heat exchange is smaller than the volume of the refrigerant before heat exchange.

The number of return-side flow path portions 11b connected to the outlet-side header opening 8b is smaller than the number of outward-side flow path portions 11a into which the refrigerant flows from the inlet-side header opening 8 a. This is because the volume of the refrigerant after heat exchange is smaller than the volume of the refrigerant before heat exchange for the same reason that the diameters of the

header openings

8a and 8b are different.

In the present embodiment, the number of the forward flow path portions 11a is 7 and the number of the return flow path portions 11b is 2, but the present invention is not limited thereto.

In addition, when the heat exchanger is used as an evaporator, the inlet and outlet of the refrigerant are reversed from the above configuration.

As shown in fig. 9, inlet openings 8aa and outlet openings 8bb are formed in the portions of the plate fins 2a that face the inlet-side header opening 8a and the outlet-side header opening 8b, respectively, in the 1 st and 2

nd end plates

3a and 3b that are positioned on both sides of the plate fin stacked body 2 configured as described above. Inlet connection pipe 4 and outlet connection pipe 5 are connected to 1 st and 2

nd end plates

3a and 3b so as to cover inlet opening 8aa and outlet opening 8 bb.

In the heat exchanger 1 of the present embodiment, as shown in fig. 1 and 9, the refrigerant flows into the plate fin laminate 2 from the 1 st inlet connection pipe 4a connected to the 1 st end plate 3a, and is discharged to the adjacent plate fin laminate 2 through the 2 nd inlet connection pipe 4b connected to the 2 nd end plate 3b and communicating with the inlet-side header flow path 10 and the inlet-side header flow path 10. The refrigerant returned by each plate fin laminate flows into the plate fin laminate 2 from the 2 nd outlet connection pipe 5b connected to the 2 nd end plate 3b, and is discharged to the outside of the heat exchanger 1 through the 1 st outlet connection pipe 5a connected to the 1 st end plate 3b and communicating with the outlet-side header flow path 14 and the outlet-side header flow path 14.

Here, the inner diameters L1 of the 1 st inlet connection pipe 4a and L1 of the 2 nd inlet connection pipe 4b are larger than the opening diameter of the inlet opening 8 aa. Further, inner diameters L2 of 1 st outlet connection pipe 5a and L2 of 2 nd outlet connection pipe 5b are larger than the opening diameter of outlet opening 8 bb.

Further, the inner diameter L1 of the 1 st inlet connection pipe 4a and the inner diameter L1 of the 2 nd inlet connection pipe 4b are larger than the inner diameter M1 of the inlet-side header flow path 10 formed by stacking the

end plates

3a, 3 b. Further, the inner diameter L2 of the 1 st outlet connection pipe 5a and the inner diameter L2 (see fig. 9 and 16) of the 2 nd outlet connection pipe 5b are larger than the inner diameter M2 (see fig. 9 and 16) of the outlet-side header flow passage 14 formed by stacking the

end plates

3a and 3 b.

Further, in the present embodiment, the outer diameter L3 of the 1 st inlet connection pipe 4a and the outer diameter L3 of the 2 nd inlet connection pipe 4b are larger than the inner diameter M1 of the inlet-side header flow path 10 formed by the lamination of the inlet opening 8aa, the outlet opening 8bb, and the plate fins 2 a. Further, the outer diameter L3 of the 1 st outlet connection pipe 5a and the outer diameter L3 of the 2 nd outlet connection pipe 5b are larger than the inner diameter M2 of the outlet-side header flow path 14. In short, the inner diameters M1, M2 are smaller than the inner diameters L1, L2 and the outer diameters L3, L4.

In the plate fin 2a (6, 7), the slits 15 are disposed between a region where the outward flow path portion 11a into which the refrigerant flows from the inflow side header opening 8a is formed and a region where the return flow path portion 11b to the outlet side header opening 8b is formed, as shown in fig. 15, 16, and the like, in order to reduce (insulate) the heat conduction between the refrigerants in the plate fin 2a (6, 7).

The connection channel 10b of the header channel 10 on the inlet side is provided in a portion of the outward flow channel 11a that is offset from the return flow channel 11 b. That is, as shown in FIG. 19, the width V of the flow path 11a-1 from the center line O of the connecting flow path 10b to the end on the return-side flow path portion 11b side is larger than the width W of the flow path 11a-2 to the end on the opposite side of the return-side flow path portion 11 b. Further, a flow dividing collision wall 17 is formed at the end of the connection channel 10b, i.e., at the opening portion connected to the outward flow channel portion 11 a. The outward flow path portion located on the extended line of the connection flow path 10b becomes the non-flow path portion 18. Therefore, the refrigerant from the connecting channel 10b collides with the flow dividing collision wall 17 to be divided (divided vertically in fig. 19), and flows through the multi-branch channel 10c on the downstream side of the connecting channel 10b to the respective channel groups above and below the outward channel 11a divided by the non-channel 18.

In addition, a header flow path 14 is also formed in the header opening 8b on the outlet side. The header flow path 14 is formed in substantially the same shape as the header flow path 10 of the header opening 8a provided on the inlet side, except that the flow dividing collision wall 17 is not provided. In the present embodiment, since the number of the return-side flow path portions 11b of the refrigerant flow path 11 group is as small as two, the connection flow path 10b is provided substantially on the center line of the return-side flow path portion 11b group.

In the plate fins 2a (6, 7) configured as described above, as shown in fig. 18A, a plurality of projections 12(1 st projection: 12a, 12aa, 2 nd projection: 12b) are formed at predetermined intervals in the longitudinal direction in the flow path region P in the 1 st plate fin 6.

Fig. 18A shows the 1 st plate fin 6. Fig. 18B shows the 2 nd plate fin 7. Fig. 18C shows a state in which the two plate fins 2a (6, 7) are superimposed (a diagram showing a displacement of the refrigerant flow path 11 group).

As shown in fig. 18A to C, the 1 st projection 12a is formed at a flat surface end 19a of a long side edge portion (a long side edge portion on both right and left sides in fig. 18A) of the plate fin. The 1 st projection 12aa is formed on the flat end 19b of both side edges of the slit 15. As shown in fig. 8, the 1 st projection 12a abuts against the flat end 19a of the long side edge portion of the 2 nd plate fin 7 adjacently opposing in the stacking direction. The 1 st projection 12aa abuts on the flat end 19b positioned at both side edges of the slit 15 of the 2 nd plate fin 7 adjacent and opposed to each other in the stacking direction. Thus, the distance between the 1 st plate fin 6 and the adjacent 2 nd plate fin 7 is defined to be a predetermined length. The 1 st projection 12a is formed so as to be located inward from the end edge of each long-side edge portion, for example, 1mm or more (on the side of the refrigerant passage 11) inward from the end edge.

As is clear from fig. 18A, the 2 nd projections 12b are formed at predetermined intervals between the passages of the refrigerant passage 11 group, in the present embodiment, the recessed flat portions 20 serving as the non-passage portions 18. The 2 nd projection 12B abuts the recessed planar portion 20 of the 2 nd plate fin 7 adjacent in the stacking direction shown in fig. 18B. Thus, the 2 nd protrusions 12b define the distance between the 1 st plate fin 6 and the 2 nd plate fin 7 in the lamination layer to be a predetermined length, similarly to the 1 st protrusions 12a and 12 aa.

Further, as shown in fig. 20, each of the projections 12(12a, 12aa, 12b) is formed by cutting out a part of the

flat end portions

19a, 19b and the recessed flat portion 20 of the 1 st plate fin 6. Hereinafter, the protrusions 12(12a, 12aa, 12b) may be referred to as cut-and-form protrusions. The cut-forming end edge Y of the cut-forming projection faces the flow direction indicated by an arrow of the 2 nd fluid flowing between the stacked layers of the plate fins 2a, and the cut-forming standing piece Z (see fig. 20) is along the 2 nd fluid flow direction. In the present embodiment, the slit protrusion is formed by slit forming in a substantially コ -shaped (substantially U-shaped) cross section such that the slit protrusion opens in the 2 nd fluid flow direction.

When the plate fins 2a (6, 7) and the end plates 3(3a, 3b) are brazed, the top surfaces of the cut projections 12(12a, 12aa, 12b) are fixed to the adjacent plate fins 2a (6, 7). Thereby integrally connecting the plate fins 2a (6, 7).

In the present embodiment, the 1 st cut-out projections 12a and 12aa and the 2 nd cut-out projection 12b may be arranged linearly along the flow direction of the 2 nd fluid (air), or may be arranged in a staggered manner.

Further, as shown in fig. 21, the plate fin 2a (6) is further formed with a plurality of projections 22(22a, 22b) on the fin flat surface portion 21 at the end portion on the turn-back side of the flow path region P in which the group of refrigerant flow paths 11 is U-turned. The projections 22(22a, 22b) are also formed by cutting the fin planar portion 21 (hereinafter, the projections 22(22a, 22b) may be also referred to as cut projections), and the cut edges Y of the cut projections 22(22a, 22b) face the flow of the 2 nd fluid. Further, the slit forming projections 22(22a, 22b) are provided on the downstream side of the positioning boss hole 13. The cut-forming protrusion 22a closest to the downstream side of the positioning boss hole 13 is formed by cutting so as to have a shape contracting the fluid flow on the downstream side of the positioning boss hole 13, for example, so that the cross-sectional shape thereof is opened in an ハ shape (inverted V shape) toward the 2 nd fluid flow direction. The projections 22b on the downstream side of the projection 22a are arranged alternately so that the center line thereof is shifted from the center line of the next projection 22b on the downstream side.

In addition, the cut-out forming projections 22(22a, 22b) are also fixed so that the top surfaces of the cut-out forming projections 22(22a, 22b) are in contact with the adjacent plate fin 2a (7) in the same manner as the cut-out forming projections 12(1 st cut-out forming projections: 12a, 12aa, 2 nd cut-out forming projection: 12 b). Thereby, the gaps between the adjacent plate fins 2a are defined to a predetermined length and the plate fins 2a are connected to each other.

As shown in fig. 13, through holes (hereinafter, referred to as positioning boss holes) 13 for positioning are formed in the plate fins 2a (6, 7) at the end of the header region H. The positioning boss holes 13 are also formed in the 1 st and 2

nd end plates

3a and 3b and the reinforcing

plates

16a and 16b laminated on both sides of the plate fin 2a (6, 7). A positioning pin jig when stacking the plurality of plate fins 2a (6, 7) is attached to the positioning boss hole 13. This enables the plurality of plate fins 2a to be stacked with high accuracy. In the present embodiment, the reinforcing

plates

16a and 16b of the laminated plate-fin structure 2 and the connection portions 9 (see fig. 5) such as bolts for connecting the 1 st and 2

nd end plates

3a and 3b also serve as positioning pin jigs.

Further, a hole outer peripheral portion (hereinafter referred to as a positioning boss hole outer peripheral portion) 13a is formed in an upper and lower direction in an outer peripheral portion of the positioning boss hole 13 provided at both end portions of the plate fin 2a (6, 7). The positioning boss hole outer peripheral portion 13a forms a space different from a flow path through which the refrigerant flows. As shown in fig. 13, the positioning boss hole outer peripheral portion 13a abuts against the plate fins 2a (6, 7) adjacent in the stacking direction, and serves as a header region support portion that holds the stacking gap of the plate fins 2 a.

The positioning boss hole outer peripheral portion 13a formed around the positioning boss hole 13 is brazed and fixed to the

header flow paths

10 and 14 and the positioning boss hole outer peripheral portion 13a of the plate fins 2a (6, 7) facing each other in the stacking direction, together with the header flow paths 10 and 14(10a, 10b, and 10c) of both the inlet and the outlet formed in the header region H shown in fig. 14. Thereby, the header region portions of the plate fins 2a (6, 7) are integrally connected.

The refrigerant flow path 11 of the present invention is described, for example, as having a circular cross-sectional shape perpendicular to the direction in which the refrigerant flows, but is not limited thereto. The cross-sectional shape of the refrigerant flow path 11 includes a rectangular shape, in addition to a circular shape.

In the present embodiment, the refrigerant flow path 11 is described as having a shape protruding in both sides in the stacking direction, but may be a shape protruding only in one side in the stacking direction. In addition, in the present invention, the circular shape also includes a circle, an ellipse, and a compound curve shape formed by a closed curve.

The heat exchanger of the present embodiment is configured as described above, and its operational effects will be described below.

First, the flow of the refrigerant and the heat exchange action are explained.

The refrigerant flows from the inlet connection pipe 4 connected to one end portion side of each plate fin laminate 2 to the header flow channels 10 of the plate fins 2a through the header openings 8a on the inflow side. The refrigerant then flows through the outer peripheral flow path 10a around the header opening 8a, the connecting flow path 10b, and the multi-branch flow path 10c to the refrigerant flow path 11 group. The refrigerant flowing through the refrigerant flow path 11 group of the plate fins 2a is turned back from the outward flow path portion 11a to the return flow path portion 11 b. Then, the refrigerant flows from the outlet connection pipe 5 to the refrigerant circuit of the refrigeration system through the outlet-side header passage 14 and the outlet-side header opening 8 b.

When flowing through the refrigerant flow paths 11, the refrigerant exchanges heat with air passing through the stacked layers of the plate fins 2a of the respective plate fin stacked bodies 2.

At this time, a strong pressure of the refrigerant is applied to the header region H of each plate-fin laminate 2 having the inlet-side header flow path 10 and the outlet-side header flow path 14, and the header region-corresponding portions of the 1 st and 2

nd end plates

3a and 3b in contact with the atmosphere undergo expansion deformation.

That is, as shown by the arrows in fig. 9, refrigerant pressures from the inlet-side header flow path 10 and the outlet-side header flow path 14 side (upward arrows in the drawing) are applied to the header region corresponding portions of the 1 st end plate 3 a.

However, in the heat exchanger of the present embodiment, not only the refrigerant pressure from the header flow path side but also the refrigerant pressure (downward arrow in the figure) from the 1 st inlet connection pipe 4a side and the 1 st outlet connection pipe 5a side are applied to the header region corresponding portion of the 1 st end plate 3 a. The inner diameter M1 (see fig. 9 and 16) of the inlet-side header flow path 10 is smaller than the inner diameter L1 of the 1 st inlet connection pipe 4a, and the inner diameter M2 (see fig. 9 and 16) of the outlet-side header flow path 14 is smaller than the inner diameter L2 of the 1 st outlet connection pipe 5 a. Therefore, the refrigerant pressures from the 1 st inlet connection pipe 4a side and the 1 st outlet connection pipe 5a side are higher than the refrigerant pressures from the

header passages

10, 14 sides, and the influence of the refrigerant pressures from the inlet-side header passage 10 and the outlet-side header passage 14 side is cancelled out. Similarly, in the header region corresponding portion of the 2 nd end plate 3b, the refrigerant pressures from the 2 nd inlet connection pipe 4b side and the 2 nd outlet connection pipe 5b side are also higher than the refrigerant pressures from the

header channels

10 and 14 side, and the influence of the refrigerant pressures from the inlet-side header channel 10 side and the outlet-side header channel 14 side is cancelled out.

Further, in the present embodiment, the outer diameters L3 of the 1 st and 2 nd

inlet connection pipes

4a and 4b and the outer diameters L4 of the 1 st and 2 nd

outlet connection pipes

5a and 5b are larger than the inner diameter M1 of the inlet-side header flow path 10 and the inner diameter M2 of the outlet-side header flow path 14. Therefore, the refrigerant pressure from the header flow path 10 side can be received by the tube walls of the 1 st and 2 nd

inlet connection tubes

4a and 4b and the 1 st and 2 nd

outlet connection tubes

5a and 5 b.

Thereby suppressing outward expansion deformation of the header region corresponding portions of the 1 st and 2

nd end plates

3a, 3 b.

In the present embodiment, the reinforcing

plates

16a and 16b are provided on the outer surfaces of the header region corresponding portions of the

end plates

3a and 3b, and the reinforcing

plates

16a and 16b are coupled to each other by the coupling portion 9. Therefore, the expansion deformation of the header region corresponding portion can be more reliably suppressed.

In the present embodiment, the refrigerant flow paths 11 provided in the plate fins 2a turn in a substantially U-shape, and the inlet-side header flow path 10 and the outlet-side header flow path 14 are concentrated on one end side of the plate fin laminate 2. Therefore, the one end portion side of the plate fin laminate 2 receives double pressure on the inlet side and the outlet side. However, according to the structure of the present embodiment, the expansion deformation can be reliably suppressed.

In the header region of the plate fin laminate 2, the inlet-side header flow path 10 has the largest flow path area. Therefore, the refrigerant pressure in the inlet-side header flow path 10 portion is also highest. However, since the inlet-side header flow path 10 is brazed in contact with the adjacent inlet-side header flow path 10, the expansion deformation can be effectively prevented. As a result, the expansion deformation of the header region corresponding portion can be prevented more reliably.

The coupling portions 9 such as bolts can be used as guide pins (jigs) when the plate fins 2a, the 1 st and 2

nd end plates

3a and 3b, and the reinforcing

plates

16a and 16b are stacked. This can improve the lamination accuracy and also improve the productivity.

Further, there is a problem that the strong pressure of the refrigerant applied to the header region H of each plate-fin laminated body 2 causes the cross section of the outer peripheral flow channels 10a of the inlet-side header flow channels 10 of the header region H to be deformed by pressure. The top surface of the outer wall of the outer peripheral flow passage 10a of the inlet-side header flow passage 10 is in a state of being brazed in contact with the outer peripheral flow passage 10a of another header flow passage 10 adjacent in the stacking direction. Therefore, the header flow path 10 in the header region H is not deformed, and a highly reliable heat exchanger can be realized.

As described above, in the case of the heat exchanger of the present embodiment, which uses a large amount of refrigerant or uses an environment-compatible refrigerant having a high compression ratio, the heat exchanger of the present embodiment can prevent the expansion deformation of the header region portion of the plate fin laminate 2 formed by laminating the

plate fin laminates

2, 2. As a result, the heat exchanger can be used in a state where the pressure of the refrigerant is higher, and a high-efficiency heat exchanger can be realized.

In this heat exchanger, the cross-sectional area of the concave groove for the refrigerant flow path formed in the plate fin 2a is reduced, thereby reducing the diameter of each flow path of the refrigerant flow path 11 group. This improves heat exchange efficiency and reduces the size.

In short, the flow path cross-sectional area of the refrigerant flow path 11 can be reduced while preventing the expansion deformation in the header region portion of the plate-fin laminated body 2, and the heat exchange efficiency can be improved.

Further, since the heat exchanger of the present embodiment is configured by connecting the plurality of plate fin stacked bodies 2 as described above, the dimension width in the plate fin stacking direction can be increased. In short, a long heat exchanger can be realized which suppresses expansion and deformation and is suitable for use in household air conditioners, business air conditioners, and the like. In the present embodiment, the heat exchanger 1 is configured by connecting a plurality of plate fin laminates 2, but the heat exchanger 1 may be configured by 1 plate fin laminate 2.

As described above, the heat exchanger according to the present embodiment can prevent expansion deformation due to refrigerant pressure by the size of the diameter of the header flow path and the diameters of the inlet and outlet connection pipes of the plate-fin stacked body 2. The heat exchanger of the present embodiment also has the following effects.

That is, in the heat exchanger of the present embodiment, the group of refrigerant flow paths 11 provided in the plate fins 2a is formed in a substantially U-shape and folded back as described above. Therefore, the refrigerant flow path length can be increased without increasing the plate fins 2 a.

This improves the heat exchange efficiency between the refrigerant and the air, and reliably brings the refrigerant into an overcooled state, thereby improving the efficiency of the refrigeration system. Further, the heat exchanger can be miniaturized.

In the present embodiment, the air and the heat-exchanged refrigerant flowing between the plate-fin stacked body 2 and the plate-fin stacked layers flow from the inlet-side header flow path 10 to the group of the connection flow path 10b, the multi-branch flow path 10c, and the refrigerant flow path 11. Here, a flow dividing collision wall 17 is provided on the downstream side of the connection flow path 10b, and the refrigerant collides with the flow dividing collision wall 17 and is divided into upward and downward flows. The refrigerant split vertically is further split from the multi-branch flow passage 10c into the refrigerant flow passages 11. This prevents the refrigerant from traveling extremely unevenly in the flow path at the upper portion of the extension line of the connection flow path 10 b.

In the present embodiment, the refrigerant flow paths 11 are formed in a U-shape, and each refrigerant flow path has a turn portion. Therefore, as is clear from fig. 19, the flow path lengths of the refrigerant flow path 11 group become longer as the distance from the outer periphery of the U-shape, in other words, the flow path 11a-2 side of the slit 15 becomes longer. Then, a drift current is generated due to the difference in the length of the passage.

However, in the present embodiment, the connection channel 10b from the header channel 10 is provided offset to the return channel side with respect to the center line O of the outward channel side channel 11a of the refrigerant channel 11 group. Therefore, the refrigerant can flow substantially uniformly through the respective flow paths while suppressing the drift.

That is, in the present embodiment, even if the flow path resistance varies depending on the flow path length from the inlet-side header flow path 10 to the outlet-side header flow path 14 of each flow path of the refrigerant flow path 11 group because the refrigerant flow path 11 group is formed in a U-shape, the refrigerant can be uniformly branched into the respective flow paths of the refrigerant flow path 11 group. This is because the connecting flow path 10b from the header flow path 10 on the inlet side is located at a position shifted toward the reverse return flow path side of the outward flow path portion 11a, and therefore the length of the branch path from the connecting flow path 10b to each outward flow path portion 11a becomes longer as it approaches the return flow path portion 11b, thereby canceling out the difference in resistance.

Therefore, the heat exchanger having a higher heat exchange efficiency can be obtained while the size reduction is advanced by the synergistic effect of the U-turn of the refrigerant flow path 11 group and the uniform flow distribution by the flow distribution collision wall 17.

Further, a slit 15 is formed between the outward flow path portion 11a and the return flow path portion 11b of the refrigerant flow path 11 group, and is thermally blocked. This prevents heat transfer from the outward flow path portion 11a to the return flow path portion 11b of the refrigerant flow path 11 group, and thus the refrigerant can be efficiently supercooled. As a result, the heat exchange efficiency is further improved.

In the heat exchanger of the present embodiment, the plurality of cut-and-formed projections 12(12a, 12aa, 12b) are provided in the flow path region P of the plate-fin stacked body 2, thereby improving the heat exchange efficiency in the flow path region P.

Specifically, the cut-formed end edge Y of the cut-formed protrusion 12(12a, 12aa, 12b) faces the fluid flow direction of the 2 nd fluid flowing between the stacked layers of the plate fin 2 a. Thus, the interval between the plate-fin stacked layers is fixed. Further, the dead water region generated on the downstream side of the cut forming projections 12(12a, 12aa, 12b) is extremely small, and the front edge effect is generated in the cut forming end edge Y portion in some cases. Further, since the slit protrusions (12a, 12aa, 12b) are slit so as to face the 2 nd fluid flow direction, the flow resistance to the 2 nd fluid can also be made small. Therefore, the heat exchange efficiency of the heat exchanger can be greatly improved while suppressing an increase in the flow path resistance of the flow path region P of the plate fin laminated body 2.

The arrangement structure of the cut projections 12(12a, 12aa, 12b) provided on the plate fin 2a may be a staggered arrangement with respect to the 2 nd fluid or may be formed more on the leeward side than on the windward side. It is sufficient to select an optimum structure for improving the heat transfer rate according to the specification and structure of the heat exchanger and the user's desire.

The cut-and-formed projections 12(12a, 12aa, 12b) are cut and formed so as to open in the direction of flow of air flowing through the gaps of the plate-fin stacked body 2. Therefore, it is not necessary to make the recessed flat portions 20 between the refrigerant flow paths thin in the direction in which air flows, that is, in the direction intersecting the refrigerant flow paths. Therefore, the recessed flat surface portion 20 located between the refrigerant flow paths can be made narrower than the case where the cut-out projections 12b are formed to be raised like cylindrical projections or the like, in accordance with the size not requiring thinning. The width of the plate fins 2a, in other words, the heat exchanger can be miniaturized by the amount of narrowing of the recessed flat portions 20.

In addition, the narrow width flat surfaces 20a and the wide width flat surfaces 20b are formed at the edges of the long side portions of the plate fins 2a by the alternating offset arrangement of the refrigerant flow channels 11 (see fig. 8). Cut projections 12a are formed on the wide flat surface 20b side, and the top surfaces of the cut projections 12a are fixed to the narrow flat surfaces 20a of the adjacent plate fins 2 a. Therefore, the width of the narrow width plane 20a may not be widened to form the protrusion. That is, the slit-formed projections are provided on the wide flat surface side by the wide flat surface 20b, and the slit-formed projections are brought into contact with and fixed to the narrow flat surfaces 20a of the plate fins 2a adjacent to the projections. Therefore, the width of the long side portion of the plate fin on the narrow plane side can be kept unchanged as the narrow plane without being increased, and the heat exchanger can be more downsized.

In the brazing of each plate fin 2a and the

end plates

3a, 3b, the top surfaces of the cut projections 12 are fixed to the adjacent plate fins 2 a. Thereby, the plate fins 2a are integrally connected. As a result, the rigidity of the plate-fin laminate 2 can be improved.

Particularly in the present embodiment, the non-flow path section 18 is formed at the upper part of the extension line of the connection flow path 10b of the refrigerant flow path 11 group, and the 2 nd cut-and-form projection 12b, which is a part of the projection 12(12a, 12aa, 12b), is provided by the non-flow path section 18. This can reliably maintain the spacing between the stacked plate fins in the group of refrigerant flow paths 11 constant. This makes it possible to stabilize the air flow in the group of refrigerant passages 11 uniformly, thereby improving the heat exchange efficiency.

The 1 st cut projections 12a provided on the long side portions of the laminated plate fin body 2 improve the strength of the long side edge portions of the laminated plate fin body 2, which tends to be weakened in strength. In particular, the 1 st cut-out projections 12aa provided on both side edge portions of the slit 15 of the plate-fin laminated body 2 improve the strength of the slit edge portions which are separated by the slit 15 and have reduced strength. Therefore, it is also possible to prevent deformation in the vicinity of the slit 5 while achieving an improvement in heat exchange efficiency.

The 1 st cut forming projections 12aa provided on both side edge portions of the slit 15 may be provided one on the other so as to straddle the slit 15. In this case, there is a problem that heat conduction occurs between the outward flow path part 11a and the return flow path part 11b of the refrigerant flow path 11 group, and the heat insulating effect of the slit 15 is reduced. However, in the present embodiment, since the protrusions 12aa are provided separately at both side edge portions of the slit 15, the problem of heat conduction that occurs such heat conduction is eliminated. The 1 st incision forming protrusion 12aa may be provided at a position apart from the slit.

The 1 st cut-forming projections 12a, 12aa provided on the long side portions of the plate fin laminate 2 and on both side portions of the slit 15 are provided at positions away from the end edges of the long sides of the plate fins of the plate fin laminate 2. Therefore, when dew condensation water is generated in the plate fins 2a of the plate-fin laminated body 2 and flows along the end edges of the plate fins 2a and is discharged, the flow of the dew condensation water is blocked by the 1 st cut-forming projections 12a and 12aa, and various problems caused by the dew condensation water accumulating in the cut-forming projections 12a and 12aa can be prevented. Therefore, a heat exchanger with high reliability can be provided.

In the heat exchanger of the present embodiment, the cut-out projections 22(22a, 22b) are also provided at the refrigerant flow path U-turn side end portions of the plate fins 2 a. Therefore, the degree of contribution of heat exchange at the U-turn side end portions of the plate fins 2a without the refrigerant flow channels 11 can be increased. Therefore, the heat exchange efficiency can be improved over the entire length of the flow path region of the plate fin 2a, and the heat efficiency of the heat exchanger can be improved.

In particular, the plate fin 2a has positioning boss holes 13 at the U-turn side end portion, and the downstream side of the positioning boss holes 13 becomes a dead water region, so that the heat exchange contribution is extremely low. In the present embodiment, since the plurality of cut-out projections 22(22a, 22b) are provided on the downstream side of the positioning boss hole 13, the heat exchange contribution can be improved over the entire downstream side of the positioning boss hole 13.

Further, the slit forming projections 22a provided on the nearest downstream side of the positioning boss hole 13 constrict the fluid flow on the downstream side of the positioning boss hole 13. Therefore, the dead water region having a low heat exchange contribution degree generated on the downstream side of the positioning screw hole can be made extremely small. As a result, the heat exchange efficiency can be further improved.

Furthermore, the respective cut-out projections 22(22a, 22b) are cut out and formed in the same manner as the projections 12(12a, 12aa, 12b) provided in the flow path region P, and the cut-out edge Y faces the 2 nd fluid flow. This can generate a leading edge effect at the cut-formed edge portion, and accordingly, the heat exchange efficiency can be further improved.

The plurality of slit-formed projections 22(22a, 22b) provided on the downstream side of the positioning boss hole 13 are arranged in a staggered manner with respect to the 2 nd fluid flow zigzag line. This can effectively exhibit the heat exchange function and improve the heat exchange contribution.

Further, the top of each cut-out protrusion 22(22a, 22b) is fixed to the adjacent plate fin 2 a. According to this structure, the short side portions of the plate fins 2a are connected and fixed in a stacked state, so the rigidity of the plate fin stacked body 2 can be improved.

The slit protrusion 22 provided on the nearest downstream side of the positioning boss hole 13 is formed by slit forming in the present embodiment in such a sectional shape as to open in an ハ -shape (inverted V-shape) toward the 2 nd fluid flow direction. The slit protrusion 22 may be formed by cutting in a substantially L-shape, and may be provided so as to face a pair of the slit protrusions. That is, the shape of the fluid flow on the downstream side of the contraction positioning boss hole 13 may be any shape.

(embodiment mode 2)

As shown in fig. 22 to 25, the heat exchanger of the present embodiment differs from the heat exchanger of embodiment 1 in the shape of the refrigerant flow path group and the installation position of the header opening. The same reference numerals are given to portions having the same functions as those of the heat exchanger according to embodiment 1, and the following description will focus on the portions having different functions.

Fig. 22 is a perspective view showing one appearance of a plate fin laminate constituting a heat exchanger according to embodiment 2. Fig. 23 is a plan view of the plate fin constituting the plate fin laminate. Fig. 24 is an exploded perspective view showing an enlarged part of the structure of the plate fin. Fig. 25 is a perspective view showing the plate-fin stacked body with the refrigerant flow path group portion cut off.

In fig. 22 to 25, the group of refrigerant flow paths 11 provided in the plate fins 2a of the heat exchanger of the present embodiment is linear. An inlet-side header opening 8a is provided on one end side of the refrigerant flow path 11 group, and an outlet-side header opening 8b is provided on the other end side. An inlet connection pipe 4 is connected to the inlet-side header opening 8a, an outlet connection pipe 5 is connected to the outlet-side header opening 8b, and the refrigerant flows out linearly from one end portion side to the other end portion side of the plate fin 2 a.

The manifold flow path 10 formed around the manifold opening 8a on the inlet side is composed of an outer peripheral flow path 10a around the manifold opening, a connection flow path 10b, and a multi-branch flow path 10 c. The connection flow path 10b is formed to extend from the outer peripheral flow path 10a in the short side direction of the plate fin 2a, and then is connected to the multi-branch flow path 10 c. The outlet-side manifold channel 14 is also configured in the same manner as the inlet-side manifold channel 10, and both have symmetrical shapes.

The

end plates

3a and 3b on both sides of the plate-fin laminated body 2 are connected by the connection portion 9 without using the reinforcing

plates

16a and 16 b. Thereby preventing the expansion deformation of the header region corresponding portions at both ends of the

end plates

3a, 3 b.

The heat exchanger configured as described above is the same as the heat exchanger described in embodiment 1, including the configuration and effects of the detailed portions, except that the refrigerant flow path 11 group is made straight, and therefore, the description thereof is omitted.

In embodiment 1, the slit-formed projections 22 provided at the U-turn side end portions of the plate fins 2a may be provided appropriately in the inlet-side and outlet-side header regions in the present embodiment. For example, the slit projections 22 may be formed on the downstream side of the header flow channel 10 which is a dead water region.

(embodiment mode 3)

The heat exchanger of the present embodiment is suitable for use as an evaporator in which the refrigerant inlet and outlet of the heat exchanger are reversed from those of embodiment 1. In the present embodiment, as shown in fig. 26 to 30, a refrigerant flow dividing control tube 24 is provided in the header passage 14 on the outlet side.

In this embodiment, a case where the heat exchanger having the structure of embodiment 1 is used as an evaporator will be described as an example.

Fig. 26 is a perspective view showing the appearance of the plate-fin stacked body of the heat exchanger according to embodiment 3. Fig. 27 is a perspective view showing a state in which the flow distribution control tubes are removed from the plate-fin stacked body. Fig. 28 is a perspective view showing a flow distribution control tube insertion portion of the plate fin laminate. Fig. 29 is a perspective view of the shunt control tube. Fig. 30 is a schematic cross-sectional view showing a flow distribution control tube portion of the plate fin laminate.

In fig. 26 to 30, the flow dividing control tube 24 is inserted into the outlet-side header flow path 14, which is the header opening 8b on the outlet side as the evaporation outlet of the refrigerant. As shown in fig. 30, the front end portion of the flow distribution control tube 24 extends to the end plate 3b on the side where the header opening is not provided. The front end portion of the flow dividing control tube 24 is closed by the end plate 3 b. The flow distribution control pipe 24 is formed of a pipe having a smaller diameter than the inner diameter of the header opening 8 b. A refrigerant flow communication gap 25 is formed between the flow dividing control tube 24 and the inner surface of the header opening. A plurality of flow distribution ports 26 are formed at substantially equal intervals in the longitudinal direction of the flow distribution control tubes 24, that is, in the stacking direction of the plate fins 2 a.

The plurality of branch flow ports 26 are formed such that the hole diameters thereof become smaller as the header opening 8b on the outlet side, which is the direction in which the refrigerant flows, approaches.

As shown in fig. 27 and 29, the flow distribution control pipe 24 is attached to the reinforcing plate 16 a. The flow distribution control tubes 24 are inserted and disposed in the header openings 8b by fastening the reinforcing plates 16a to the end plates 3a on both sides of the plate-fin laminate 2. The flow distribution control tubes 24 have a length reaching the 2 nd plate fin 7 of the plate fin stacked body 2 that is the farthest (opposite side) among the plurality of plate fin stacked bodies 2 connected and coupled.

The inlet connection pipe 4 is connected and fixed to a surface of the reinforcing plate 16a to which the flow dividing control pipe 24 is attached, the surface facing the flow dividing control pipe 24.

Further, an outlet connection pipe 5 is connected and fixed to the reinforcing plate 16 a. The flow distribution control tube 24 may be in contact with the end plate 3b so as to close the distal end portion thereof.

In the heat exchanger configured as described above, the refrigerant gas flowing from the header opening 8a on the inlet side to the header passage 14 on the outlet side through the group of refrigerant passages 11 flows into the flow dividing control tubes 24 from the refrigerant flow common space 25 through the plurality of flow dividing ports 26(26a, 26b) formed in the tube walls of the flow dividing control tubes 24, as indicated by arrows in fig. 30. Then, the refrigerant flows out from the outlet-side header opening 8b to the outlet connection pipe 5.

Here, the flow dividing port 26 provided in the flow dividing control tube 24 is formed such that the diameter of the flow dividing port becomes smaller as the outlet-side header opening 8b approaches. Therefore, the amount of refrigerant flowing through each of the refrigerant flow paths 11 in the group can be made uniform.

That is, in the heat exchanger of the present embodiment, the refrigerant flow path 11 is made smaller in diameter, so that the pressure loss of the refrigerant is several times larger than that of the header flow path 14 on the outlet side of the header flow path 10 on the inlet side. On the other hand, the refrigerant split flow is greatly affected by the distribution of pressure loss. Thus, even if the flow dividing control tube 24 is provided in the header passage 10 on the inlet side, which is common in the prior art, the pressure loss of the header passage 14 on the outlet side is several times higher than that of the inlet side, and therefore the refrigerant flowing through the refrigerant passage 11 depends on the pressure loss of the header passage 14 on the outlet side. Therefore, the flow cannot be split as designed.

However, in the heat exchanger of the present embodiment, the flow dividing control tube 24 is provided in the header passage 14 on the outlet side where the pressure loss is high. This makes the pressure loss distribution in the axial direction in the outlet-side header flow path 14, which largely affects the flow distribution, uniform. This makes it possible to equalize the flow rates of the refrigerant flowing through the respective flow paths of the refrigerant flow path 11 group.

In the heat exchanger of the present embodiment, the refrigerant flowing from the inlet connection pipe 4 passes through the inlet-side header opening 8a, is introduced into the refrigerant flow paths 11 inside the respective plate fins, and flows into the outlet-side header opening 8 b. Then, the refrigerant flows out of the outlet connection pipe 5.

At this time, due to the pressure loss occurring in each flow path, the refrigerant flows through the refrigerant flow paths 11 of the plate fins located closer to the inlet connection tube 4 (the refrigerant flow paths of the plate fins located closer to the left in fig. 30) more easily than the refrigerant flow paths 11 of the plate fins located farther from the inlet connection tube 4 (the refrigerant flow paths of the plate fins located closer to the right in fig. 30). In other words, there is a possibility that unevenness is generated in the flow rate of the refrigerant.

In the present embodiment, the flow dividing control tube 24 is inserted into the outlet-side header opening 8b, and the flow dividing port 26a closest to the outlet side (the portion closer to the left in fig. 30) is made smaller than the flow dividing port on the opposite outlet side (the portion closer to the right in fig. 30) of the flow dividing control tube 24. Thereby increasing the pressure loss of the refrigerant passing through the outlet-side flow dividing port. As a result, the refrigerant flow rate can be prevented from being biased, the refrigerant amount in the 1 st fluid flow path 11 inside each plate fin can be made uniform, and the heat exchange efficiency can be improved.

As a result, the heat exchanger of the present embodiment can improve the heat exchange efficiency in the group portion of the refrigerant flow path 11, and can provide a heat exchanger with higher heat efficiency.

Further, the refrigerant flow distribution uniformizing structure is a simple structure in which only the flow distribution control tube 24 penetrates the flow distribution port 26, and therefore the heat exchanger can be provided at low cost.

The flow distribution control pipe 24 is integrally provided to the reinforcing plate 16 a. Therefore, the flow distribution control tubes 24 can be inserted and disposed in the outlet-side header passage 14 only by attaching the reinforcing plate 16 a. As a result, defective joining of the plate fins due to melting of the brazing material at the brazed portions of the plate fins, which is problematic when the flow dividing control tubes 24 are additionally mounted by welding or the like, and accompanying quality defects such as leakage of the refrigerant can be prevented, and a high-quality and high-efficiency heat exchanger can be provided.

The reinforcing plate 16a is made of a material having a smaller potential difference between the flow dividing control tube 24 and the outlet connection tube 5 than the potential difference between the flow dividing control tube 24 and the outlet connection tube 5 when they are directly connected (the reinforcing plate 16a is made of stainless steel, the flow dividing control tube 24 is made of aluminum, and the outlet connection tube 5 is made of copper). This can prevent the occurrence of dissimilar metal contact corrosion which occurs when the flow dividing control pipe 24 is directly connected to the outlet connection pipe 5. As a result, the reliability of long-term use can be greatly improved. In particular, in the heat exchanger for an air conditioner in which the inlet connection pipe 4 and the outlet connection pipe 5 are often formed of copper pipes and the flow dividing control pipe 24 is formed of aluminum or the like, a significant effect can be expected.

In the present embodiment, the flow distribution control pipe 24 is provided on the reinforcing plate 16a, but is not limited thereto. The flow distribution control pipe 24 may be provided on the end plate 3a side, or in the case of a type not using the reinforcing plate 16a, the flow distribution control pipe 24 and the outlet connection pipe 5 may be provided on a surface facing the end plate 3 a.

In the present embodiment, the group of refrigerant passages 11 is not limited to having a U-shape. The straight refrigerant flow path 11 group described in embodiment 2 may be used.

(embodiment mode 4)

Embodiment 4 is a refrigeration system configured using the heat exchangers of the respective embodiments described above.

In the present embodiment, an air conditioner will be described as an example of a refrigeration system. Fig. 31 is a refrigeration cycle diagram of the air conditioner. Fig. 32 is a schematic sectional view showing an indoor unit of the air conditioner.

In fig. 31 and 32, the air-conditioning apparatus is composed of an outdoor unit 51 and indoor units 52 connected to the outdoor unit 51. The outdoor unit 51 includes a compressor 53 that compresses a refrigerant, a four-way valve 54 that switches a refrigerant circuit during cooling and heating operation, an outdoor heat exchanger 55 that exchanges heat between the refrigerant and outside air, and a pressure reducer 56 that reduces the pressure of the refrigerant. Further, in the indoor unit 52, an indoor heat exchanger 57 and an indoor fan 58 that exchange heat between the refrigerant and the indoor air are disposed. The compressor 53, the four-way valve 54, the indoor heat exchanger 57, the decompressor 56, and the outdoor heat exchanger 55 are connected by a refrigerant circuit to form a heat pump refrigeration cycle.

In the refrigerant circuit of the present embodiment, a refrigerant is used which is obtained by mixing 2 components or 3 components, using tetrafluoropropene or trifluoropropene as a base component, and difluoromethane, pentafluoroethane, or tetrafluoroethane so that the global warming potential is 5 or more and 750 or less, preferably 350 or less, and more preferably 150 or less.

In the air conditioner, the four-way valve 54 is switched to communicate the discharge side of the compressor 53 with the outdoor heat exchanger 55 during the cooling operation. The refrigerant compressed by the compressor 53 becomes a high-temperature and high-pressure refrigerant, and is sent to the outdoor heat exchanger 55 through the four-way valve 54. The refrigerant exchanges heat with the outside air to dissipate heat, becomes a high-pressure liquid refrigerant, and is sent to the decompressor 56. The refrigerant is decompressed by the decompressor 56 to become a low-temperature low-pressure two-phase refrigerant, and is sent to the indoor unit 52. In the indoor unit 52, the refrigerant enters the indoor heat exchanger 57, exchanges heat with indoor air to absorb heat, evaporates and gasifies, and becomes a low-temperature gas refrigerant. At this time, the indoor air is cooled to cool the room. Further, the refrigerant returns to the outdoor unit 51 and returns to the compressor 53 via the four-way valve 54.

During the heating operation, the four-way valve 54 is switched to communicate the discharge side of the compressor 53 with the indoor unit 52. The refrigerant compressed by the compressor 53 becomes a high-temperature and high-pressure refrigerant, and is sent to the indoor unit 52 through the four-way valve 54. The high-temperature and high-pressure refrigerant enters the indoor heat exchanger 57, exchanges heat with indoor air to dissipate heat, and is cooled to become a high-pressure liquid refrigerant. At this time, the indoor air is heated to heat the room. Thereafter, the refrigerant is sent to the decompressor 56, and decompressed at the decompressor 56 to become a low-temperature low-pressure two-phase refrigerant. The refrigerant is sent to the outdoor heat exchanger 55, exchanges heat with the outside air, and evaporates and gasifies. Further, the refrigerant returns to the compressor 53 via the four-way valve 54.

In the refrigeration system configured as described above, the heat exchangers described in the above embodiments are used for the outdoor heat exchanger 55 and the indoor heat exchanger 57. This enables a high-performance refrigeration system with high energy saving performance to be realized.

Industrial applicability of the invention

The invention provides a small-sized and high-efficiency heat exchanger and a high-performance refrigeration system using the same, which can eliminate expansion deformation in a header region even in a heat exchanger used for household and enterprise air conditioners and the like by setting the diameters of a header flow path and inlet and outlet connecting pipes of a plate fin laminated body. This makes it possible to widely use the heat exchanger and various refrigeration equipment used in air conditioners for home use and business use, etc., and the industrial value thereof is high.

Description of the reference numerals

1 Heat exchanger

2-plate fin laminated body

2a plate fin

3a, 3b end plate

4 Inlet connecting pipe (inlet manifold)

4a 1 st inlet connection pipe

4b 2 nd inlet connection pipe

5 Outlet connecting pipe (outlet header)

5a 1 st outlet connection pipe

5b 2 nd outlet connection pipe

6 st plate fin

6a 1 st plate-like member

6b 2 nd plate-like member

7 nd 2 nd plate fin

8. 8a, 8b header openings

9 connecting part (bolt and nut)

10 manifold flow path (inlet side manifold flow path)

10a peripheral flow path

10b connecting channel

10c multiple branch flow path

11 refrigerant flow path (1 st fluid flow path)

11a forward flow path part

11b return side channel part

13 through hole (boss hole for positioning)

13a hole peripheral part (positioning boss hole peripheral part)

14 manifold flow path (outlet manifold flow path)

15 slit

16a, 16b reinforcing plate

17 shunting collision wall

18 non-flow path part

19a, 19b planar end portions

20 depressed plane part

20a narrow plane

20b broad width plane

21 fin plane part

22(22a, 22b) projection (cut-out projection)

24-flow dividing control tube

25 gap for refrigerant circulation

26. 26a, 26b branch-off opening

51 outdoor machine

52 indoor machine

53 compressor

54 four-way valve

55 outdoor heat exchanger

56 pressure reducer

57 indoor heat exchanger

58 indoor fan.

Claims

1. A heat exchanger, comprising:

a plate fin laminate body configured by laminating a plurality of plate fins each having a flow path through which the 1 st fluid flows;

a 1 st end plate and a 2 nd end plate respectively arranged at both ends of the plate fin laminate in the stacking direction;

a 1 st inlet connection pipe connected to the 1 st end plate, into which the 1 st fluid flows;

a 1 st outlet connection pipe connected to the 1 st end plate, through which the 1 st fluid flows out;

a 2 nd inlet connecting pipe connected with the 2 nd end plate and communicated with the 1 st inlet connecting pipe; and

a 2 nd outlet connecting pipe connected with the 2 nd end plate and communicated with the 1 st outlet connecting pipe,

a 2 nd fluid flows between the plate fin lamination layers of the plate fin lamination body to perform heat exchange between the 1 st fluid and the 2 nd fluid, wherein

The plurality of plate fins each include a flow path region having a plurality of 1 st fluid flow paths through which the 1 st fluid flows and a header region having a header flow path communicating with the plurality of 1 st fluid flow paths,

the header flow path includes an inlet-side header flow path communicating the 1 st inlet connection pipe with the 2 nd inlet connection pipe and an outlet-side header flow path communicating the 1 st outlet connection pipe with the 2 nd outlet connection pipe,

the 1 st fluid flow path is formed by concave grooves provided in the plurality of plate fins,

the inner diameter of the inlet-side header flow path is smaller than the inner diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe,

the outlet-side header flow path has an inner diameter smaller than the inner diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe,

a flow distribution control pipe inserted into the header flow path is connected to the inlet opening of the 1 st end plate,

the 1 st end plate is formed of a material such that a potential difference between the flow dividing control tube and the 1 st inlet connection tube or a potential difference between the flow dividing control tube and the 1 st outlet connection tube is smaller than a potential difference when the flow dividing control tube and the 1 st inlet connection tube are directly connected or the flow dividing control tube and the 1 st outlet connection tube are directly connected.

2. The heat exchanger of claim 1, wherein:

the inner diameter of the inlet-side header flow path is smaller than the outer diameters of the 1 st inlet connection pipe and the 2 nd inlet connection pipe,

the inner diameter of the outlet-side header flow path is smaller than the outer diameters of the 1 st outlet connection pipe and the 2 nd outlet connection pipe.

3. The heat exchanger of claim 1 or 2, wherein:

the plurality of 1 st fluid flow paths are respectively formed in a U-shape,

the inlet-side header flow path and the outlet-side header flow path are arranged on one end side of each of the plurality of plate fins,

the 1 st inlet connection pipe and the 2 nd inlet connection pipe are respectively communicated with the inlet opening and the outlet opening of the inlet-side header flow path,

the 1 st outlet connection pipe and the 2 nd outlet connection pipe communicate with the inlet opening and the outlet opening of the outlet-side header flow path, respectively.

4. The heat exchanger of claim 1 or 2, wherein:

comprising a plurality of said plate-fin laminate,

the plate fin laminate is joined to each other by the 2 nd inlet connection pipe and the 2 nd outlet connection pipe.

5. A refrigeration system, characterized by:

comprising a heat exchanger according to any one of claims 1 to 4.