WO2002025189A1

WO2002025189A1 - Heat exchanger and method of manufacturing the heat exchanger

Info

Publication number: WO2002025189A1
Application number: PCT/JP2001/008241
Authority: WO
Inventors: Akihiko Takano; Shunichi Furuya
Original assignee: Zexel Valeo Climate Control Corporation
Priority date: 2000-09-25
Filing date: 2001-09-21
Publication date: 2002-03-28
Also published as: JP2002098486A

Abstract

A heat exchanger (7) and a method of manufacturing the heat exchanger; the heat exchanger used in a refrigerant circulating compression refrigeration cycle (1) and exchanging heat between the high and low pressure sides of the refrigerant, comprising a tube body (710) allowing the refrigerant to circulate therethrough on the high and low pressure sides for performing a heat exchange by utilizing a heat conducting through the tube body, the tube body further comprising a first flow passage layer (711) formed by disposing a high-pressure side refrigerant flow passage (711) and a second flow passage layer formed by disposing a low-pressure side refrigerant flow passage (712a), wherein the inlet part (720) and outlet part (730) of the first flow passage layer and the inlet part (740) and outlet part (750) of the second flow passage layer are provided at the end part of the tube body.

Description

Akitoda

Heat exchanger and method for manufacturing the same

The present invention relates to a heat exchanger that is used in a compression refrigeration cycle that circulates refrigerant and exchanges heat between a high-pressure side and a low-pressure side of the refrigerant, and a method for manufacturing the same. Background art

As for the compression type refrigeration cycle that circulates the refrigerant, the refrigeration efficiency can be improved by exchanging heat between the high pressure side and the low pressure side of the refrigerant.

Heat exchangers for exchanging heat between the high-pressure side and the low-pressure side of the refrigerant are also described in Japanese Patent Application Laid-Open Nos. Hei 9-111, 152, and Hei 11-114,207. o

By the way, as for the refrigeration cycle, there is a demand for saving installation space and further reducing the production cost.As mentioned above, a simple heat exchanger for exchanging heat between the high-pressure side and low-pressure side of the refrigerant is required. What has been desired is a structure having more excellent performance.

For example, as in a heat exchanger described in the above-mentioned Japanese Patent Application Laid-Open No. 9-11131, a tube is formed in a spiral shape, and refrigerant inlet portions are provided on the outer side and the center side of the spiral, respectively. In addition, the one provided with the outlet portion has a complicated structure for circulating the refrigerant and is very difficult to manufacture.

In recent years, the C 0 ₂ is adopted as the refrigerant, the refrigeration Saikuru is used the pressure inside the radiator exceed the critical point of the refrigerant.

A refrigeration cycle in which the pressure inside the radiator exceeds the critical point of the refrigerant requires extremely high pressure resistance, and the heat exchanger described above can improve the heat exchange efficiency and endure the refrigerant pressure. Configuration is required.

The present invention has been made in view of the above circumstances, and provides a heat exchanger capable of efficiently exchanging heat between a high pressure side and a low pressure side of a refrigerant and a method for manufacturing the same. It is intended to provide. Disclosure of the invention

The invention described in claim 1 of the present application is used in a compression type refrigeration cycle that circulates refrigerant, and in a heat exchanger that exchanges heat between a high pressure side and a low pressure side of the refrigerant, the heat exchanger is A tube body through which the high-pressure side and the low-pressure side refrigerant flows, and performing the heat exchange by heat transmitted to the tube body, wherein the tube body has a line of the high-pressure side refrigerant flow paths. A first flow path layer, and a second flow path layer in which the low-pressure-side refrigerant flow paths are arranged. An end of the tube body has an inlet section of the first flow path layer. The heat exchanger has a structure in which a refrigerant and an outlet are provided, and the inlet and the outlet of the second flow path layer are provided. According to such a structure, the high-pressure side and the low-pressure side of the refrigerant are efficiently heated. Exchanged o

That is, for the tube body, by arranging the refrigerant passages on the high pressure side and arranging the refrigerant passages on the low pressure side, the heat transfer surface with the refrigerant on the high pressure side and the refrigerant passage on the low pressure side are arranged. The heat transfer surface of the refrigerant is expanded, and the heat transfer between the two refrigerants is ensured. In addition, since the diameter of each refrigerant channel is relatively small, it is possible to ensure high pressure resistance.

Furthermore, if the inlet and outlet of the first channel layer and the inlet and outlet of the second channel layer are provided at the end of the tube body, the heat exchanger has a simple configuration. And can be easily manufactured.

In the invention described in claim 2 of the present application, in claim 1, the one end of the tube body is provided with an inlet of the first flow path layer and an outlet of the second flow path layer. A heat exchanger having a structure in which an outlet of the first flow path layer and an inlet of the second flow path layer are provided at the other end of the tube body. The refrigerant on the side flows from one end of the tube to the other end, and the refrigerant on the low pressure side flows from the other end of the tube to one end. In other words, in the tube body, the high-pressure side and the low-pressure side of the coolant flow in directions opposite to each other. In this way, if the high-pressure side and the low-pressure side of the refrigerant are caused to flow in the directions facing each other, the heat exchange efficiency of the heat exchanger is further improved. If the high-pressure refrigerant and the low-pressure refrigerant flow in the same direction, a satisfactory temperature difference is obtained near the outlet of the first flow channel layer and the outlet of the second flow channel layer. In some cases, such an inconvenience is avoided according to the configuration of the present invention.

The invention described in claim 3 of the present application is the invention according to claim 1 or 2, wherein the tube body is a heat exchanger configured by a single extruded tube. The road is formed as small as possible. The invention described in claim 4 of the present application is the invention according to claim 1 or 2, wherein the tube body is formed by assembling or brazing a plurality of extruded tubes, and the plurality of extruded tubes are provided with the plurality of extruded tubes. This is a heat exchanger having a configuration in which one of the first flow path layer and the second flow path layer is provided. According to such a configuration, each refrigerant flow path is formed as small as possible. Further, an inlet and an outlet of the first channel layer and an inlet and an outlet of the second channel layer are provided for each tube.

The invention described in claim 5 of the present application is the invention according to any one of claims 1 to 4, wherein the tube body includes at least one of the first channel layer and the second channel layer. According to such a configuration, the second flow path layer or the first flow path layer is interposed between the plurality of first flow path layers or the plurality of second flow path layers. Heat transfer between them is performed more reliably.

In the invention described in claim 6 of the present application, in claim 5, the tube body includes one first flow path layer and two second flow path layers sandwiching the first flow path layer. According to such a configuration, the tube body is configured in a well-balanced manner.

The invention described in claim 7 of the present application is the heat exchanger according to any one of claims 1 to 6, wherein the inlet portion and the outlet portion of the first flow path layer are symmetrical to each other. According to such a configuration, the flow velocity distribution of the refrigerant in the first flow path layer is set in a well-balanced manner.

The invention described in claim 8 of the present application is directed to any one of claims 1 to 7 The inlet and outlet of the second flow path layer are heat exchangers that are symmetrical to each other. According to such a configuration, the flow velocity distribution of the refrigerant in the second flow path layer is set in a well-balanced manner. Is done.

According to a ninth aspect of the present invention, in the heat exchanger according to any one of the first to eighth aspects, the heat exchanger has a configuration in which a heat insulating material is attached around the tube body. And the heat exchange between the high-pressure refrigerant and the low-pressure refrigerant is promoted. As a result, the performance of the refrigeration cycle is improved.

The invention described in claim 10 of the present application is the liquid crystal display device according to any one of claims 1 to 9, wherein, with respect to a cross section of the tube body, a sum of cross sectional areas in the refrigerant flow path on the high pressure side is X, and When the sum of the cross-sectional areas in the refrigerant passage on the low pressure side is Y, these are

X <Y

According to such a configuration, the flow rates of the high-pressure side and the low-pressure side refrigerant are ensured in a well-balanced manner, and as a result, the heat exchange efficiency is improved.

That is, since the low-pressure side refrigerant expands more reliably than the high-pressure side refrigerant, in the tube body, the sum of the cross-sectional areas of the low-pressure side refrigerant flow path is expressed by the cross-sectional area of the high-pressure side refrigerant flow path. By setting the sum to be larger than the sum of the flow rates, the difference in flow velocity between the high-pressure side and the low-pressure side refrigerant is reduced.

In the invention described in claim 11 of the present application, in claim 10, the sum X of the cross-sectional area in the refrigerant passage on the high-pressure side and the sum 断面 of the cross-sectional area in the refrigerant passage on the low-pressure side are: ,

Χ = η · Υ

1.7≤η≤5.0

According to such a configuration, the flow rates of the refrigerant on the high-pressure side and the low-pressure side are ensured in a more balanced manner.

That is, in the present invention, the condition of claim 8 is further limited in terms of numerical values while considering heat exchange efficiency. It is set between 1.7 times and 5.0 times.

The invention described in claim 12 of the present application is characterized in that, in any one of claims 1 to 11, the equivalent diameter of the high-pressure side refrigerant flow path and the equivalent diameter D _{2 of the} low-pressure side refrigerant flow path Is

0.4 [mm] ≤D i≤ 1.2 [mm]

0.4 [mm] ≤D ₂ ≤ 1.2 [mm]

According to such a configuration, it is possible to set the pressure resistance, the heat exchange property, and the flow path resistance in a well-balanced manner.

That is, when these equivalent diameter D _{l 5} D ₂ is increased, the flow resistance will be low reduction, pressure resistance, heat exchange is reduced. Further, when the D ₂ have these equivalent diameter D decreases, pressure resistance, heat exchange is improved, the channel resistance increases. However, the present invention is configured such that by setting the equivalent diameter _{Dl 3} D ₂ to such a value, the pressure resistance and the heat exchange property can be suitably secured while suppressing the flow path resistance to a practical range. I have.

The invention described in claim 13 of the present application is characterized in that, in the heat exchanger according to any one of claims 1 to 12, the amount of heat transferred between the high pressure side and the low pressure side of the refrigerant is The amount of heat transferred when the temperature difference of

If it is 0 [%], the heat exchanger has a configuration of about 60 to 95 [%]. With such a configuration, the performance of the heat exchanger is sufficiently ensured. In other words, the ratio of the amount of heat transferred between the high pressure side and the low pressure side of the refrigerant increases as the length of the tube increases, and decreases as the length of the tube decreases. By setting the amount of heat transferred between the pressure side and the low-pressure side to such a value, it is possible to avoid unnecessary increase in the size and weight of the heat exchanger and to achieve better performance. I have.

The invention described in claim 14 of the present application is the heat exchanger according to any one of claims 1 to 13, wherein the refrigeration cycle is configured such that a pressure inside a radiator exceeds a critical point of the refrigerant. It is.

Here, the critical point is the limit on the high temperature side (that is, the limit on the high pressure side) where the gas layer and the 禆 layer coexist, and is the end point of one of the vapor pressure curves. Critical point The pressure, temperature, and density at, respectively, are the critical pressure, critical temperature, and critical density. If the pressure exceeds the critical point of the refrigerant inside the radiator, the refrigerant will not condense.

In other words, the heat exchanger can efficiently exchange heat between the high-pressure side and the low-pressure side of the refrigerant, and is suitably used in a refrigeration cycle in which the pressure inside the radiator exceeds the critical point of the refrigerant. Is done.

The invention described in claim 15 of the present application is used in a compression type refrigeration cycle for circulating a refrigerant, and in a method of manufacturing a heat exchanger for exchanging heat between a high pressure side and a low pressure side of the refrigerant, the method comprises: The heat exchanger includes a tube body through which the high-pressure side and the low-pressure side coolant flows, and performs the heat exchange by heat transmitted to the tube body. And a second flow path layer in which the low-pressure-side refrigerant flow paths are arranged in a row, and the first flow path layer and the second flow path layer are arranged in a row. A plurality of extruded tubes provided on one side are brazed, and when brazing the plurality of extruded tubes, fins are arranged on the surface of the extruded tube, and then the fins are placed. This is a method of manufacturing a heat exchanger with a According to such a configuration, the plurality of extruded Ji Interview part, is efficiently brazed by heat transmitted to the fins, the heat exchanger is easily manufactured. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram showing a refrigeration cycle according to a specific example of the present invention.

FIG. 2 is a perspective view showing a heat exchanger according to a specific example of the present invention. FIG. 3 is a cross-sectional view illustrating a tube body according to a specific example of the present invention. FIG. 4 is a perspective view illustrating a manufacturing step of the tube body according to a specific example of the present invention.

FIG. 5 is a perspective view showing a tube body manufacturing process according to a specific example of the present invention. FIG. 6 is a perspective view showing a tank according to a specific example of the present invention. FIG. 7 is a perspective view showing a heat exchanger according to a specific example of the present invention. FIG. 8 is a perspective view showing a heat exchanger according to a specific example of the present invention. FIG. 9 is a cross-sectional view showing a tube body according to a specific example of the present invention. FIG. 10 is a cross-sectional view showing a tube body according to a specific example of the present invention.

FIG. 11 is a cross-sectional view illustrating a main part of a heat exchanger according to a specific example of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

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

The compression-type refrigeration cycle 1 shown in FIG. 1 is used for in-vehicle cooling mounted on an automobile, and includes a compressor 2 for compressing a refrigerant and a radiator 3 for cooling the refrigerant compressed by the compressor 2. A decompressor 4 that decompresses and expands the refrigerant cooled by the radiator 3, an evaporator 5 that evaporates the refrigerant depressurized by the decompressor 4, and a refrigerant that flows out of the evaporator 5 into a gas layer. An accumulator 6 that separates the refrigerant into a liquid layer and sends the refrigerant in the gas layer to the compressor 2 is provided.

The coolant adopts a C 0 _2, the internal pressure of the radiator 3, the operating conditions such as air temperature, exceed the critical point of the refrigerant.

In the refrigerating cycle 1, a heat exchanger 7 for exchanging heat between the high-pressure side and the low-pressure side of the refrigerant is provided between the radiator 3 and the decompressor 4 and between the accumulator 6 and the compressor 2. Is provided. The heat exchanger 7 improves the efficiency of the refrigeration cycle 1 by exchanging heat between the high-pressure side refrigerant and the low-pressure side refrigerant.

The white arrow in the drawing indicates the direction in which the high-pressure side refrigerant flows, and the black arrow indicates the direction in which the low-pressure side refrigerant flows.

As shown in FIGS. 2 and 3, the heat exchanger 7 of the present embodiment includes a tube body 110 through which the high-pressure side and the low-pressure side refrigerant flows, and heat is transferred by the heat transferred to the tube body 7 10. Exchange. The tube body 7110 has a first flow path layer 711 formed by arranging high-pressure side refrigerant flow paths 711a and a second flow path layer formed by arranging a low-pressure side refrigerant flow path 712a. And two flow path layers 12.

The high-pressure side refrigerant flow path 711a and the low-pressure side refrigerant flow path 712a are illustrated in the form of elliptical ones, or they may be circular, elliptical, or square. , Triangular, etc.

In addition, the equivalent diameter of the high-pressure side refrigerant flow path 71 1a and the equivalent diameter of the low-pressure side refrigerant flow path 71 2a are determined in consideration of pressure resistance, heat exchange property, and flow path resistance. It is set in the range of ~ 1.2 [mm].

That, together with the considerable diameter of the coolant channel 7 1 1 a of the high pressure side, when the equivalent diameter of the low pressure side refrigerant flow path 7 1 2 a and D _2, these,

0.4 [mm] ≤Ώ _λ ≤ 1.2 [mm]

0.4 [mm] ≤D ₂ ≤ 1.2 [mm]

Is established.

The tube body 7100 is formed by brazing a plurality of flat extruded tubes. Specifically, one extruded tube provided with the first flow path layer 711 and the second flow path Two extruded tubes provided with layers 7 12 are laminated in parallel and alternately, and this is heated and brazed by heating in a furnace.

However, the tube body 7 10 includes one first flow path layer 7 1 1 and two second flow path layers 7 1 2 sandwiching the first flow path layer 7 1 1, and is connected to the high pressure side of the refrigerant. Heat exchange with the low pressure side takes place between these layers.

The dimensions of the tube body 70 of this example are 30 to 60 [mm] in width and 4.5 to 9.0 [mm] in thickness. The length is set in consideration of the balance between heat exchange performance and installation space.

Further, at the end of the tube body 7 10, there are an inlet 7 20 and an outlet 7 20 of the first flow path layer 7 11 1, and an inlet 7 And an outlet 7400.

The inlet 7 2 0 of the first flow path layer 7 1 1 connects the piping 1 10 on the radiator 3 side A joint type joint block 721, a single pipe section 722 extending from the joint block 721, and a sunset section 723 communicating the tip of the pipe section 722 are provided. One end of an extruded tube provided with the first flow path layer 7 11 is inserted into the tank section 7 23 and brazed. The first flow path layer 7 11 communicates with the tank section 7 23.

The outlet section 730 of the first flow path layer 111 is a union-type joint block 732 that connects the pipe 120 on the pressure reducer 4 side, and one pipe section extending from the joint block 732. The extruded tube provided with the first flow path layer 7 1 1 and the tank 7 3 3 is provided with a nozzle section 7 3 3 communicating the tip of the pipe section 7 32 The other end is inserted and brazed. The first flow path layer 7 11 communicates with the tank section 7 33.

The inlet part 7400 of the second flow path layer 712 is composed of a union type joint work 741 for connecting the pipe 13 on the accumulator 6 side, and two pipe parts 7 extending from the joint work 741. 4 2 and two tank sections 7 4 3 communicating the ends of the pipe sections 7 4 2 with each other, and two extrusions provided with a second flow path layer 7 1 2 for each tank section 7 4 3 One end of the molded tube is inserted and brazed, respectively. The second flow path layer 7 12 communicates with the tank section 7 43.

The outlet 750 of the second flow path layer 712 is a union type joint block 715 for connecting the piping 140 on the compressor 2 side, and two pipe sections extending from the joint block 750. 7 5 2 and two tanks 7 5 3 communicating the ends of the pipes 7 52 respectively, and two extrusions provided with a second flow path layer 7 1 2 for each tank 7 5 3 The other end of the molded tube is inserted and brazed, respectively. The second flow path layer 7 12 communicates with the tank section 753.

In addition, an inlet 720 of the first flow channel layer 711 and an outlet 7500 of the second flow channel layer 7112 are provided at one end of the tube 7 10, The outlet portion 730 of the flow channel layer 711 and the inlet portion 740 of the second flow channel layer 712 are provided at the other end of the tube body 710. Accordingly, the high-pressure side refrigerant flows from one end of the tube: 110 to the other end, and the low-pressure side refrigerant flows from the other end of the tube body 110 to one end. Flows to That is, in the tube body 110, the high-pressure side and the low-pressure side of the refrigerant flow in directions opposite to each other.

As described above, the heat exchange efficiency of the heat exchanger 7 can be further improved by flowing the high-pressure side and the low-pressure side of the refrigerant in directions facing each other. If the high-pressure side refrigerant and the low-pressure side refrigerant flow in the same direction, the outlet section 7300 of the first flow path layer 711 and the outlet section 7500 of the second flow path layer 7 In the vicinity, those temperature differences may not be obtained satisfactorily, but according to the configuration of this example, such inconvenience can be avoided.

In addition, regarding the inlet 720 and the outlet 7330 of the first flow path layer 711, the tank 723 of the inlet 720 and the tank 734 of the outlet 73.0 are as follows. It has a cylindrical shape along the width direction of the first flow path layer 711. The pipe section 722 of the inlet section 702 and the pipe section 732 of the outlet section 730 communicate with both ends of the tank sections 723, 733 in different directions. ing. The inlet part 720 and the outlet part 730 of the first flow path layer 71 1 are symmetric with each other.

Furthermore, regarding the inlet part 7400 and the outlet part 750 of the second flow path layer 712, the tank part 743 of the inlet part 7400 and the tank part 754 of the outlet part 750 It has a cylindrical shape along the width direction of the second flow path layer 7 12. And, the pipe part 742 of the inlet part 7400 and the pipe part 752 of the outlet part 750 communicate with both ends of each tank part 743, 753 in different directions. ing. The inlet 740 and the outlet 7500 of the second flow path layer 712 are symmetric with each other.

However, according to such a configuration, it is possible to average the flow velocity of the refrigerant in each of the refrigerant passages 711a on the high pressure side, and to reduce the flow velocity of the refrigerant in each of the refrigerant passages 712a on the low pressure side. Can be averaged, and as a result, the heat exchange efficiency can be improved.

The direction of each joint block 7 2 1, 7 3 1, 7 4 1, 7 5 1 It can be set arbitrarily by bending the middle part of the eve parts 722, 732, 742, 752.

In addition, regarding the cross section of the tube body 710, when the total cross-sectional area in the high-pressure side refrigerant flow channel 711a is X and the total cross-sectional area in the low-pressure side refrigerant flow channel 712a is Y, They are,

X <Y

Is established.

In particular, in the case of this example, the value of に対する with respect to X is set between 1.7 times and 5.0 times, and the total X of the cross-sectional areas in the high-pressure side refrigerant flow path and the low-pressure side refrigerant The sum of the cross-sectional areas in the channel is 流路

Xii η

1.7≤η≤5.0

Is established.

That is, since the low-pressure side refrigerant expands more reliably than the high-pressure side refrigerant, by adopting such a configuration in the tube body 710, the flow velocity difference between the high-pressure side and the low-pressure side refrigerant is reduced. The flow rate of the refrigerant has been reduced to ensure a good balance.

4 to 5 are perspective views showing the steps of manufacturing the tube body 710. The tube body 710 is constructed by assembling each extruded tube, each pipe section 722, 132, 742, 752, and each tank section 723, 733, 743, 753, and heat-treating this assembly in a furnace. Attached. Prior to the heat treatment, brazing filler metal and flux are provided at key points of each member. In the case of this example, the brazing material is Si powder, which is mixed with a flux and applied.

Then, as shown in these figures, fins F are arranged on the surface of each extruded tube during the heat treatment (see FIG. 4). Fin F is removed after brazing (see Fig. 5). However, brazing of multiple extruded tubes is efficiently performed by the heat transmitted to the fins F. In addition, each joint pro- cess 721, 731, 741, 751 is provided by torch brazing after such brazing in a furnace. In other words, thermal deformation due to heat treatment in the furnace is avoided.

As described above, the heat exchanger 7 of the present embodiment can be easily manufactured, and can efficiently perform heat exchange between the high-pressure side and the low-pressure side of the refrigerant.

In particular, according to the heat exchanger 7, when the refrigeration cycle 1 operates efficiently, the temperature difference between the high pressure side and the low pressure side of the refrigerant is about 1 to 10 ° C. In particular, the amount of heat that moves between the high-pressure side and the low-pressure side of the refrigerant is approximately 60 to 9 if the amount of heat that moves when the temperature difference is 0 ° C is 100 [%]. 5 [%].

Note that the tube body 110 of this example was formed using an extruded tube, or if the required pressure resistance can be satisfactorily secured, a tube formed and brazed plate is used. May be configured. In this case, the plate is formed by mouth forming or press forming.

Furthermore, the tube body 7 10 of this example is formed by brazing a plurality of extruded tubes. However, if sufficient heat exchange between the extruded tubes can be obtained, such brazing may be omitted. Good. That is, the tube body 7100 may be one in which a plurality of extruded tubes are assembled in close contact.

Further, each part of the heat exchanger 7 can be further simplified by reducing the number of parts and using common parts. For example, as shown in FIG. 6, each of the tank sections 7 2 3 and 7 5 3 at the inlet section 7 20 of the first flow path layer 7 11 and the outlet section 7 50 of the second flow path layer 7 12 However, it is also possible to constitute with an integral extruded member. In this case, a brazing member is brazed to the key of the extruded member. Further, such an extruded member is referred to as each of the tank sections 7 2 3 and 7 5 3 at the outlet section 7 30 of the first channel layer 7 11 and the inlet section 7 40 of the second channel layer 7 12. It is also possible to make them common.

As described above, according to the heat exchanger of this example, the heat exchanger includes the tube body through which the high-pressure side and the low-pressure side refrigerant flows, and is transmitted to the tube body. The tube body is composed of a first flow path layer having a high-pressure side refrigerant flow path and a second flow path having a low-pressure side flow path. Since the inlet and outlet of the first channel layer and the inlet and outlet of the second channel layer are provided at the end of the tube body, the high pressure side of the refrigerant and the low pressure The heat can be exchanged efficiently with the side.

That is, for the tube body, by arranging the refrigerant passages on the high pressure side and arranging the refrigerant passages on the low pressure side, the heat transfer surface with the refrigerant on the high pressure side and the refrigerant passage on the low pressure side are arranged. The heat transfer surface can be enlarged, and the heat transfer between the two refrigerants can be reliably performed. In addition, since the diameter of each refrigerant flow path is relatively small, high pressure resistance can be ensured.

Furthermore, if the inlet and outlet of the first channel layer and the inlet and outlet of the second channel layer are provided at the end of the tube body, the heat exchanger has a simple structure. It can be easily manufactured.

Further, according to the heat exchanger of the present example, at one end of the tube body, an inlet of the first flow path layer and an outlet of the second flow path layer are provided, and the other end of the tube body is provided. Since the outlet is provided with the outlet of the first channel layer and the inlet of the second channel layer, the heat exchange efficiency of the heat exchanger can be further improved. If the high-pressure refrigerant and the low-pressure refrigerant flow in the same direction, the temperature difference between the outlets of the first and second flow path layers will not be satisfactory. However, according to the configuration of the present invention, such inconvenience can be avoided.

Also, according to the heat exchanger of this example, the tube body is formed by assembling or brazing a plurality of extruded tubes, and the plurality of extruded tubes are provided with the first flow path layer and the second flow tube. Since one of the road layers is provided, each of the refrigerant passages can be formed as small as possible. The inlet and outlet of the first channel layer and the inlet and outlet of the second channel layer can be provided for each tube.

In addition, according to the heat exchanger of the present example, since the tube body includes at least one of the first flow path layer and the second flow path layer, the plurality of first flow path layers or the plurality of first flow path layers are provided. The second channel layer or the first channel layer is interposed between the second channel layers, so that heat transfer between the two refrigerants can be performed more reliably.

Further, according to the heat exchanger of the present example, the tube body includes one first flow path layer and two second flow path layers sandwiching the second flow path layer, so that the tube body can be configured in a well-balanced manner. it can.

Further, according to the heat exchanger of the present example, the inlet and outlet of the first flow path layer are symmetrical with each other, so that the flow velocity distribution of the refrigerant in the first flow path layer can be set in a well-balanced manner. ·

Further, according to the heat exchanger of this example, the inlet and outlet of the second flow path layer are symmetrical to each other, so that the flow velocity distribution of the refrigerant in the second flow path layer can be set in a well-balanced manner.

Further, according to the heat exchanger of this example, regarding the cross section of the tube body, when the sum of the cross-sectional areas in the refrigerant passage on the high pressure side is X and the sum of the cross-sectional areas in the refrigerant passage on the low pressure side is Υ , They are,

Χ <Υ

Therefore, the flow rates of the refrigerant on the high-pressure side and the low-pressure side can be ensured in a well-balanced manner, and as a result, the heat exchange efficiency can be improved.

In other words, since the low-pressure side refrigerant expands more reliably than the high-pressure side refrigerant, in the tube body, the sum of the cross-sectional areas of the low-pressure side refrigerant flow path 、 is calculated as the cross-sectional area of the high-pressure side refrigerant flow path. By increasing the flow rate of the refrigerant on the high-pressure side and the low-pressure side, it is possible to reduce the difference in flow velocity between the high-pressure side and the low-pressure side. , The sum of the cross-sectional areas in the refrigerant passage on the low pressure side Υ

Xii η

1.7≤η≤5.0

Therefore, the flow rates of the refrigerant on the high-pressure side and the low-pressure side can be ensured in a more balanced manner.

In other words, in this example, the values of X and Υ are more desirably limited while considering the heat exchange efficiency, and the value of に対する for X is from 1.7 times. It is set between 5.0 times.

Further, according to the heat exchanger of this example, the equivalent diameter of the high-pressure side refrigerant flow path and the equivalent diameter D _{2 of the} low-pressure side refrigerant flow path are as follows:

0.4 [mm] ≤D! ≤ 1.2 [mm]

0.4 [mm] ≤D ₂ ≤ 1.2 [mm]

Therefore, the pressure resistance, the heat exchange property, and the flow path resistance can be set in a well-balanced manner.

That is, when these equivalent diameter D ₂ is increased, the flow resistance will be low reduction, pressure resistance, heat exchange is reduced. Further, when these equivalent diameter D ₂ is smaller, pressure resistance, heat exchange is improved, the channel resistance increases. However this example is more to set the equivalent according to the diameter D ₂ value, while suppressing the flow resistance in the practical range, and configured to suitably secure the pressure resistance and the heat exchange.

Further, according to the heat exchanger of this example, in the heat exchanger, the amount of heat that moves between the high-pressure side and the low-pressure side of the refrigerant is equal to the amount of heat that moves when the temperature difference becomes 0 ° C. If it is 0 [%], it is about 60-95 [%], so the performance of the heat exchanger can be satisfactorily secured.

Further, in the refrigeration cycle of this example, the pressure inside the radiator exceeds the critical point of the refrigerant. In other words, the heat exchanger can efficiently exchange heat between the high-pressure side and the low-pressure side of the refrigerant, and is suitably used in a refrigeration cycle in which the pressure inside the radiator exceeds the critical point of the refrigerant. can do.

According to the heat exchanger manufacturing method of this example, when brazing a plurality of extruded tubes, fins are arranged on the surface of the extruded tubes, and then the fins are removed. Extruded tubes can be brazed efficiently by the heat transferred to the fins, and heat exchangers can be easily manufactured.

Next, a second specific example of the present invention will be described with reference to FIG.

As shown in the figure, the heat exchanger 7 of this example is provided around the tube body 7 10. It is equipped with a heat insulator 760. The heat insulating member 760 is for ensuring heat insulation between the tube body 710 and the outside. In the present embodiment, the heat insulating member 760 is a sponge made of rubber or synthetic resin. Since other configurations are the same as those of the above-described specific example, common members are denoted by the same reference numerals, and description thereof is omitted.

As described above, according to the heat exchanger of this example, since the heat insulating material is attached around the tube body, heat insulation with the outside is secured, and heat exchange between the high-pressure refrigerant and the low-pressure refrigerant is performed. Can be promoted. As a result, the performance of the frozen cycle can be further improved.

Next, a third specific example of the present invention will be described with reference to FIG.

As shown in the figure, the heat exchanger 7 of the present example is formed by bending a tube body 710 into a U-shape. Since other configurations are the same as those of the above-described specific example, common members are denoted by the same reference numerals and description thereof is omitted.

As described above, the tube body may be appropriately shaped in consideration of the installation space of the heat exchanger.

Next, a fourth specific example of the present invention will be described with reference to FIG.

As shown in the figure, the tube body 110 of the present example is composed of two extruded tubes provided with a first flow path layer 711, and three extruded tubes provided with a second flow path layer 712. Tubes are stacked in parallel and alternately and brazed. In this case, the pipe section is used for the inlet section 720 and the outlet section 730 of the first flow path layer 711 and the inlet section 740 and the outlet 750 of the second flow path layer 712. Provide the required number of 7 2 2, 7 3 2, 7 4 2, 7 5 2 and tank sections 7 2 3, 7 3 3, 7 4 3, 7 5 3 respectively. Since other configurations are the same as those of the above-described specific example, common members are denoted by the same reference numerals and description thereof is omitted.

As described above, the tube body may be provided with more first and second flow path layers.

Next, a fifth specific example of the present invention will be described with reference to FIGS. As shown in these figures, the tube body 7 10 of the present example is composed of a single extruded tube. Each tank section 72 3, 73 33, 74 43, 75 53 is provided for such a single extruded tube. Also, the ends of the extruded tube, considering each tank section 7 2 3 7 3 3 7 4 3 7 5 3 of assembly property, Note _c is subjected to appropriate processing, the other configurations Since this is the same as the specific example described above, common members are denoted by the same reference numerals, and description thereof is omitted.

As described above, according to the heat exchanger of this example, since the tube body is formed of a single extruded tube, each refrigerant channel can be formed as small as possible. Further, the first channel layer and the second channel layer can be provided integrally without brazing. Industrial applicability

The present invention is a heat exchanger and its production method used in a refrigeration cycle generally for automobiles and home air conditioners, among others, to adopt the example C 0 ₂ as the refrigerant, the critical point of the pressure inside the radiator coolant It is suitable for refrigeration cycles that exceed the above.

Claims

The scope of the claims

1. A heat exchanger that is used in a compression refrigeration cycle that circulates a refrigerant and that exchanges heat between a high-pressure side and a low-pressure side of the refrigerant.

The heat exchanger includes a tube body through which the high-pressure side and the low-pressure side refrigerant flows, and performs the heat exchange by heat transmitted to the tube body.

The tube body includes: a first flow path layer in which the high-pressure side refrigerant flow paths are arranged; and a second flow path layer in which the low-pressure side refrigerant flow paths are arranged. Characterized in that an end portion of the heat exchanger is provided with an inlet portion and an outlet portion of the first flow channel layer, and an inlet portion and an outlet portion of the second flow channel layer.

2. One end of the tube body is provided with an inlet of the first flow path layer and an outlet of the second flow path layer, and the other end of the tube body is provided with the first flow path layer. 2. The heat exchanger according to claim 1, wherein an outlet of the flow channel layer and an inlet of the second flow channel layer are provided.

3. The heat exchanger according to claim 1, wherein the tube body is formed of a single extruded tube.

4. The tube body is formed by assembling or brazing a plurality of extruded tubes, and each of the plurality of extruded tubes is provided with one of the first channel layer and the second channel layer. The heat exchanger according to claim 1 or 2, wherein:

5. The heat exchanger according to claim 1, wherein the tube body includes at least one of the first channel layer and the second channel layer.

6. The heat exchanger according to claim 5, wherein the tube body includes one first flow path layer and two second flow path layers sandwiching the first flow path layer. .

7. The inlet and outlet of the first channel layer are symmetrical to each other. The heat exchanger according to any one of claims 1 to 6, characterized in that:

8. The heat exchanger according to claim 1, wherein an inlet portion and an outlet portion of the second flow path layer are symmetric with each other.

9. The heat exchanger according to claim 1, wherein a heat insulating material is provided around the tube body.

10. With respect to the cross section of the tube body, when the sum of the cross-sectional areas in the high-pressure side refrigerant flow path is represented by: ,

X <Y

10. The heat exchange according to any one of claims 1 to 9, wherein

1 1. The sum X of the cross-sectional areas in the high-pressure side refrigerant flow path and the sum 断面 of the cross-sectional areas in the low-pressure side refrigerant flow path 、

X2 π

1.7≤η≤5.0

10. The heat exchanger according to claim 10, wherein:

1 2. And the equivalent diameter of the high-pressure side refrigerant flow path of D ^, the equivalent diameter D ₂ of the refrigerant flow path of the low pressure side,

0.4 [mm] ≤D _X ≤ 1.2 [mm]

0.4 [mm] ≤D ₂ ≤ 1.2 [mm]

The heat exchanger according to any one of claims 1 to 11, wherein:

13. In the heat exchanger, the amount of heat that moves between the high-pressure side and the low-pressure side of the refrigerant is equal to the amount of heat that moves when the temperature difference between them is 0 ° C.

The heat exchanger according to any one of claims 1 to 12, wherein the heat exchanger is approximately 60 to 95 [%], where 0 [%].

14. The heat exchange according to any one of claims 1 to 13, wherein the refrigeration cycle has a pressure inside a radiator higher than a critical point of the refrigerant.

15. A method for producing a heat exchanger for use in a compression refrigeration cycle that circulates refrigerant and exchanging heat between a high pressure side and a low pressure side of the refrigerant,

The heat exchanger includes a tube body through which the high-pressure side and the low-pressure side refrigerant flows, and performs the heat exchange with heat transmitted to the tube body.

The tube body includes a first flow path layer in which the high-pressure side refrigerant flow paths are arranged, and a second flow path layer in which the low-pressure side refrigerant flow paths are arranged. A plurality of extruded tubes each provided with one of the first flow path layer and the second flow path layer are brazed,

When brazing the plurality of extruded tubes, a fin is disposed on the surface of the extruded tubes, and then the fins are removed.