JP2000220982A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger for improving a heat exchanging performance by improving pressure resistances of a heat exchange tube and a header pipe and preventing an increase in its weight. SOLUTION: In the heat exchanger comprising a heat exchange tube 2 having a refrigerant channel 2a of a circular section, header pipes connected to ends of the tubes 2 to supply and receive a refrigerant, and fins 3 mounted between the tubes 2; refrigerant channel of the pipes each has a circular section, a profile of the tube 2 has a circular section, the fins mounted on the tube 2 have recesses 3a each having a curvature along the profile of the tube, and the recesses 3a are brought into contact with the tube 2 so that the fins 3 are mounted on the tube 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger in which a refrigerant flowing through a heat exchanger exchanges heat by heat transmitted to a heat exchange tube.

[0002]

2. Description of the Related Art Conventionally, there has been known a heat exchanger formed by connecting a heat exchange tube for exchanging heat of a refrigerant with a pair of header pipes for receiving and sending the refrigerant.

[0003] That is, the refrigerant introduced from one header pipe flows through the refrigerant flow path inside the heat exchange tube, and then is discharged from the other header pipe, and the heat exchange of the refrigerant is performed by the heat transmitted to the heat exchange tube. Done.

[0004] A heat exchange tube used in this type of heat exchanger is formed from an aluminum alloy or the like by a method such as extrusion molding.

Further, the heat exchanger has fins which are in contact with the heat exchange tubes, so that the contact area between the heat exchange tubes and the fins is increased, and the heat transfer transmitted from the tubes to the fins is increased. , And is configured to enhance heat exchange performance. In recent years, CFC-based refrigerants have a global warming effect and the like, and therefore there is a strong demand for the ban on the use of these refrigerants and the direction of reduction. For this reason, Japanese Patent No. 2804844 and Japanese Patent Application Laid-Open No. 10-1942.
No. 1 discloses a refrigeration cycle using carbon dioxide (CO ₂ ), which does not destroy the ozone layer, as a refrigerant as an alternative refrigerant to a CFC-based refrigerant.

When CO ₂ is used as a refrigerant in a refrigeration cycle, heat is radiated from the refrigerant which has become high temperature and high pressure.
The state of the refrigerant when flowing through the heat exchanger is in a supercritical region beyond the critical point of the gas-liquid two-phase state, and when the normal refrigerant in the gas-liquid two-phase state flows through the heat exchanger. By comparison, it is assumed that excessive pressure is applied to the heat exchanger.

For example, when CO ₂ is used as a refrigerant,
It is considered that a heat exchanger that exerts a heat radiating effect of the high-temperature and high-pressure refrigerant is required to have a pressure resistance six times or more as compared with a case where a refrigerant in a gas-liquid mixed state flows.

When a supercritical refrigerant is used in the refrigeration system, the pressure resistance required for the heat exchanger is ensured by increasing the thickness of members such as a heat exchange tube and a header pipe through which the refrigerant flows. Conceivable. However, if members such as the heat exchange tube or the header pipe are made thicker, the outer shape of the heat exchanger itself is enlarged, which causes a problem that the layout of the refrigeration system is reduced in a vehicle where the mounting space is limited. Further, when the thickness of the heat exchange tube and the header pipe, which constitute the heat exchanger, is increased, the weight of the heat exchanger also increases, and the weight of the refrigeration system is reduced when mounted on the vehicle body. .

Therefore, the present invention improves the pressure resistance of the heat exchange tubes and header pipes through which the refrigerant flows, prevents the weight of the heat exchanger from increasing, and uses a refrigerant having a high pressure resistance requirement. Another object of the present invention is to provide a heat exchanger that can be reduced in weight.

[0010]

According to a first aspect of the present invention, there is provided a heat exchange tube having a refrigerant passage having a circular cross section, a fin abutting on the tube, and a communication connection with the tube. In a heat exchanger that includes a header pipe that sends and receives a refrigerant and that performs heat exchange by heat transmitted to the tubes and the fins, the heat exchange tube having a refrigerant flow path having a circular cross section has a tube outer shape with a circular cross section. The fin mounted between the tubes is a heat exchanger having a concave portion having substantially the same curvature as the outer shape of the tube, and the concave portion being in contact with the outer shape of the tube having a circular cross section.

When the refrigerant flow path has a circular cross section, the pressure of the flowing refrigerant is uniformly applied to the inside of the refrigerant flow path, so that the pressure resistance can be improved.

When the refrigerant passage of the heat exchange tube has a circular cross section, and the outer shape of the heat exchange tube has a circular cross section,
The tube volume can be minimized while maintaining a wall thickness that can withstand the pressure load of the refrigerant flowing through the inside, thereby preventing an increase in weight.

When the outer shape of the heat exchange tube is circular in cross section, a fin provided with a concave portion having a curvature along the outer shape of the tube is provided.
The contact area between the fin and the tube can be increased by contacting the recess. Therefore, the heat conductivity transmitted from the tube to the fin side increases, and the heat exchange performance can be improved.

According to a second aspect of the present invention, in the heat exchanger according to the first aspect, a fin is mounted between the reciprocating tubes.

As described above, the tube having the refrigerant flow path having a circular cross section is formed, for example, so as to reciprocate in a meandering manner.
By mounting fins between the reciprocating tubes, the heat exchange area is enlarged, and the heat exchange performance can be improved.

According to a third aspect of the present invention, in the first aspect of the present invention, the heat exchange tubes and the fins are alternately laminated to form a multi-stage layer, and each tube end is formed of a pair of headers. This is a heat exchanger configured to be connected to a pipe.

As described above, the heat exchange tubes and the fins are alternately stacked in multiple stages, so that the heat exchange area is enlarged and the heat exchange performance can be improved.

According to a fourth aspect of the present invention, in the second aspect of the present invention, a fin is mounted between the reciprocating tubes, and the heat exchanger in which the tube ends are connected to the header pipe is reciprocated. A plurality of heat exchangers are arranged in parallel so that the continuous surfaces of the tubes and fins are perpendicular to the direction of ventilation of the external air, and the heat exchangers are connected and connected to form a single heat exchanger. It is a vessel.

For example, when the heat exchanger is mounted on a vehicle body, the surface on which the heat exchanger can be installed in the ventilation direction of the external air is as follows.
It is limited to a certain range by the design of the car.

According to the present invention, a continuous surface of the heat exchange tubes and the fins is provided in the direction in which the external air flows through the heat exchanger, and a plurality of heat exchangers are similarly arranged in parallel. In addition, the heat exchange area in contact with the external air is enlarged, and the heat exchange performance can be improved.

According to a fifth aspect of the present invention, in the third aspect of the present invention, the heat exchange tubes and the fins are alternately laminated, and the tube ends are connected to a pair of header pipes. A plurality of heat exchangers are arranged in parallel so that the longitudinal direction of the laminated tubes and fins is orthogonal to the direction of external air flow, and the header pipes of each heat exchanger are connected and connected to each other. This is a heat exchanger having the following configuration.

As described above, by arranging a plurality of heat exchangers such that the longitudinal direction of the tubes of the heat exchanger in which the heat exchange tubes and the fins are stacked in multiple stages is orthogonal to the direction of the external air flow, The heat exchange area in contact with the metal is expanded, and the heat exchange performance can be improved.

According to a sixth aspect of the present invention, in the heat exchanger according to any one of the first to fifth aspects, the refrigerant flow path of the header pipe has a circular cross section.

As described above, when the refrigerant flow path of the header pipe is circular in cross section, the pressure of the refrigerant flowing through the header pipe is evenly applied to the header pipe, and the pressure resistance of the header pipe is improved. .

According to a seventh aspect of the present invention, in the heat exchanger of the sixth aspect, the inner diameter of the header pipe does not exceed 10 mm, and the thickness of the header pipe does not exceed 5 mm. It is a vessel.

In order to ensure the pressure resistance required for the header pipe, the thickness of the header pipe is set in consideration of the effects of the internal pressure applied to the inside of the header pipe and the tensile stress of the material constituting the header pipe. There is a need.

If the refrigerant flow path diameter is 10 mm or more, the pressure applied to the header pipe increases, and the thickness of the header pipe needs to be increased accordingly, resulting in an increase in weight. Also, if the coolant flow path diameter is set small,
Due to the flow of the refrigerant, the pressure applied to the header pipe is reduced.Thus, the thickness of the header pipe is reduced and the problem of weight increase is avoided. The performance as a header pipe for sending and receiving is reduced.

Therefore, when the refrigerant flow path diameter is not larger than 10 mm, the outer diameter of the header pipe can be determined based on the expression (1) described in the embodiment of the invention described later. is there.

For example, when aluminum is used as a material for forming a header pipe, the tensile stress of aluminum is 10 kg / mm ² . The pressure on the high pressure side of the refrigerant is
Since the pressure is about six times as high as the pressure of the refrigerant in a normal gas-liquid mixed state, the internal pressure applied to the member also increases, and pressure resistance is required.

Therefore, the outer diameter of the header pipe can be set to about 20 mm according to the expression (1) described later.

Therefore, when the refrigerant pipe diameter is set to a value not exceeding 10 mm, the required pressure resistance is ensured by setting the thickness of the header pipe to a value not exceeding 5 mm. It becomes possible.

Further, if the header pipe is formed with a minimum thickness to secure the required pressure resistance, an increase in weight is limited and the layout property on the vehicle is improved.

In addition to the header pipe, even in the case of a tube having a circular cross section, the tube is formed in consideration of the tensile stress of the members constituting the tube, the refrigerant flow path diameter, and the internal pressure applied to the tube. The thickness can be set.

According to an eighth aspect of the present invention, in the first aspect, the tube and the header pipe are a heat exchanger formed by molding aluminum or an aluminum alloy.

Forming a tube or header pipe using aluminum or an aluminum alloy has the advantage that the tube or header pipe can be easily formed at low cost. However, for example, when using a refrigerant that becomes a supercritical region when flowing through the heat exchanger as a refrigerant, in order to ensure the pressure resistance required for the heat exchanger, the thickness of each member increases, There is a problem that the weight increase becomes large.

In the present invention, since the required pressure resistance is ensured and the weight is prevented from increasing, it is possible to form a tube or a header pipe using aluminum or an aluminum alloy, thereby reducing the cost of heat. An exchanger is formed.

According to a ninth aspect of the present invention, in the heat exchanger according to any one of the first to eighth aspects, the refrigerant flowing into and out of the heat exchanger is in a gaseous state. .

As described above, when the high-temperature and high-pressure medium in the gaseous state flows between the heat exchangers in the gaseous state, the heat exchanger is required to have high pressure resistance. With the configuration of the heat exchanger of the present invention, even when flowing through a gaseous medium that requires high pressure resistance, it is possible to prevent an increase in weight and a deterioration in layout for securing pressure resistance, The heat exchanger of the present invention is used.

In a refrigeration cycle using a refrigerant that requires high pressure resistance, the heat exchanger of the present invention also
Can be used.

According to a tenth aspect of the present invention, in the first to ninth aspects of the present invention, the refrigerant flowing through the heat exchanger is a heat exchanger using carbon dioxide (CO ₂ ). .

When carbon dioxide is used as a refrigerant in a refrigeration cycle, a high-pressure refrigerant in a supercritical region exceeding a critical point in a gas-liquid two-phase state flows through the heat exchanger.

Therefore, the heat exchanger is required to have a pressure resistance that is at least six times higher than that in the case where a normal refrigerant in a gas-liquid mixed state flows. According to the heat exchanger of the present invention described above, since it is designed to satisfy high pressure resistance, it is possible to use carbon dioxide which is in a supercritical state as a refrigerant.

[0043]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view showing a heat exchanger of this embodiment. The heat exchanger 1 has fins 3 and 3 mounted thereon, and a heat exchange tube 2 formed in a meandering shape. A pair of header pipes 5 provided at the end of the tube 2,
6 is a gas cooler.

Each of the header pipes 5 and 6 is connected to a refrigerant supply pipe. One header pipe 5
Is supplied through the heat exchange tube 2 and discharged from the other header pipe 6.

FIG. 2 is a perspective view showing a schematic configuration of the heat exchange tube 2 and the fins 3. In FIG. 2, reference numeral 4 denotes a louver.

As shown in FIG. 2, in the tube of this embodiment, the refrigerant passage 2a is formed in a circular cross section, and the outer shape of the tube 2 is also formed in a circular cross section.

Also, fins 3 mounted between the tubes 2
Has a concave portion 3a having a curvature along the outer shape of the tube 2 having a circular cross section, and the tube 2 is in contact with the concave portion 3a.

When the refrigerant passage 2a of the tube 2 is formed to have a circular cross section, the refrigerant pressure is uniformly applied to the inside of the refrigerant passage 2 and the pressure resistance can be improved. Further, since the outer shape of the tube 2 of the present example is formed to have a circular cross section, high pressure resistance is required while keeping the wall thickness capable of withstanding a pressure load, minimizing the volume increase. Also in the heat exchanger, the weight of the heat exchange tube can be prevented from increasing.

The fins 3 mounted between the tubes 2
Is provided with a concave portion 3a having a curvature along the outer shape of the tube 2 having a circular cross section. When the tube 2 is in contact with the concave portion 3a, the contact area between the tube 2 and the fin 3 is increased, and Since the heat conductivity transmitted to the fins 3 increases, the heat exchange performance can be improved.
Further, since the fins 3 have the concave portions 3a substantially matching the curvature of the outer shape of the tube 2, the area of the fins 3 mounted between the tubes 2 increases, and the heat exchange area increases.

As shown in FIG. 1, in the present embodiment, the medium passages formed in the header pipes 5 and 6 to which the ends of the tubes 2 are connected are also formed in a circular cross section. As described above, when the refrigerant flow path is formed to have a circular cross section, the pressure of the refrigerant is uniformly applied to the refrigerant flow path, so that the pressure resistance is improved.

In this case, the refrigerant flow path diameter of the header pipe does not exceed 10 mm, and the thickness of the header pipe is 5 m.
The thickness is set so as not to exceed m.

The relationship between the outer diameter of the header pipe and the inner diameter of the refrigerant flow path formed in the header pipe is determined in consideration of the internal pressure applied to the header pipe and the tensile stress of the material constituting the header pipe as follows: 1) It can be determined according to the equation. (1) σ = P (r2 ² + r1 ² ) / (r2 ² −r1 ² ) where σ is the tensile stress of the material constituting the tube, P is the pressure inside the tube, r2 is the outer radius of the tube, r1 indicates a coolant flow path radius of the tube.

For example, when aluminum is used as a material for forming a header pipe, the tensile stress of aluminum is 10 kg / mm ² . When the internal pressure applied to the header pipe is 600 kg / cm ² and the refrigerant flow path diameter of the header pipe is 10 mm, the outer diameter of the header pipe is calculated according to the above equation (1).
The outer diameter of the header pipe can be set to 20 mm.

When CO ₂ or the like which requires high pressure resistance is used as the refrigerant flowing through the refrigeration cycle, if the diameter of the refrigerant flow path is 10 mm or more, the amount of flowing refrigerant increases,
Since the header pipe is required to have higher pressure resistance, it is necessary to make the header pipe thicker, which results in an increase in material cost and an increase in weight of the heat exchanger.

Therefore, the refrigerant flow path diameter of the header pipe is 1
An extent not exceeding 0 mm is considered appropriate. When CO ₂ is used as the refrigerant, a high-pressure refrigerant in a supercritical region exceeding the critical point of the gas-liquid two-phase state flows through the heat exchanger. It is assumed that a pressure resistance of at least 6 times the pressure resistance required when the refrigerant flows through is required.

When the outer diameter of the header pipe is calculated according to the above equation (1) in consideration of these conditions, the minimum outer diameter is 20 mm. From this result, assuming that the thickness of the header pipe does not exceed 5 mm, when the coolant flow path diameter of the header pipe is set to a value not exceeding 10 mm, the minimum thickness ensuring the required pressure resistance is secured. Can be set to form a header pipe, and an increase in weight can be prevented.

The thickness of the tube having a circular cross section can be set based on the above equation (1).

As described above, since the heat exchanger of this embodiment is designed to secure the required pressure resistance and to minimize the increase in weight, it is possible to use an extruded material made of aluminum or an aluminum alloy. Thus, the heat exchanger 1 can be formed lightly and at low cost.

Next, another specific example of the heat exchanger of the present invention will be described.

FIG. 3 is a perspective view showing a schematic configuration of another specific example of the heat exchanger.

As shown in FIG. 3, the heat exchanger 10 of this embodiment
A plurality of meandering reciprocating tubes 24, 25, 26 are connected between a pair of header pipes 5, 6, and fins 3 are mounted between the meandering reciprocating tubes.

The heat exchanger 10 of the present embodiment is arranged such that the surface where the tubes and the fins are continuous is orthogonal to the direction in which external air flows.

As in this example, by arranging a plurality of tubes with fins in parallel between tubes that reciprocate in a meandering manner, the area for exchanging heat with external air increases, and the heat exchange performance improves.

For example, an excellent air conditioning function is required for a one-box vehicle or the like having a large indoor space. In this case, a required air conditioning function can be achieved by enlarging the heat exchange area and mounting a heat exchanger with improved heat exchange performance.

In a vehicle, the range of the surface area with respect to the direction of the external air flow is limited to a certain range depending on the vehicle body design and the like. On the other hand, it is expected that the mounting space of the refrigeration device will increase with the size of the vehicle body.

Therefore, when a plurality of heat exchangers are arranged in parallel while keeping the same surface area range in the external air ventilation direction as in this embodiment, the heat contact with the external air can be prevented without any problem in the mounting space. The heat exchange performance is improved by increasing the exchange area.

FIG. 4 shows another embodiment of the heat exchanger of the present invention. The heat exchanger 11 of this embodiment is a tube in which tubes 12 having a refrigerant passage and an outer shape with a circular cross section are stacked in multiple stages and stacked. Fins 13 are mounted between the tubes 12, and the ends of the tubes 12 stacked in a multi-stage are connected to a pair of header pipes 14 and 15.

As described above, the tube 12 and the fin 13
When the heat exchanger 11 is formed by alternately stacking the heat exchangers 11, heat exchange performance is improved due to an increase in the heat exchange area.

The header pipes 14 and 15 of this embodiment are
Refrigerant channels 14a and 15a having circular cross sections are formed.

FIG. 5 shows a configuration in which the heat exchangers 16 and 17 having the configuration shown in FIG. 4 are arranged in parallel so that the longitudinal direction of the cross section of the tube 12 and the fins 13 is perpendicular to the ventilation direction of the external air. It is a perspective view which shows the schematic structure of the heat exchanger 23 which connected and connected the pipes 19 and 20 with the piping 22 in one. Note that the arrows in the figure indicate the direction of ventilation of the external air.

As shown in FIG. 5, as shown in FIG.
The refrigerant flows through the plurality of heat exchangers 16 and 17 in parallel to increase the flow rate of the refrigerant, increase the heat exchange area, improve the heat exchange performance, and cool the refrigerant at once.

Further, in consideration of the state of the refrigerant which is sequentially cooled as it flows through the heat exchangers 16 and 17, a plurality of heat exchangers 16 and 17 are arranged in parallel to form a refrigerant passage. The heat exchanger 23 has improved heat exchange performance.

For example, a high-temperature and high-pressure refrigerant flows from the header pipe 18 in the rear row in the direction of the external air flow, and a partition plate is installed inside the header pipe. When the refrigerant flow path of the heat exchanger is configured such that the refrigerant flows in the direction, the refrigerant flows through the tubes of the heat exchanger 16 sequentially from the rear row, and the refrigerant that has been cooled to some extent flows in the external air ventilation direction. Since heat flows between the tubes of the heat exchanger 17 constituting the closest refrigerant flow path, the heat radiation performance is improved.

In addition, as described above, in addition to the heat exchanger tube having a circular cross section, a flat tube may be used.
It is also conceivable to form a plurality of refrigerant passages having circular cross sections.

For example, FIG. 6 shows a structure in which a plurality of refrigerant passages 27a having a circular cross section are formed in a tube 27 having a flat outer cross section.

In this example, the flat cross section refers to a cross sectional shape of a tube having at least flat surfaces on the upper and lower surfaces of the tube 27.

When the refrigerant passage 27a of the tube 27 is formed in a circular cross section, the pressure of the refrigerant is evenly applied in the refrigerant passage, so that the pressure resistance is improved.

Even when the heat exchange tube is formed to have a flat cross section, the heat exchange tube needs to have a thickness enough to withstand the pressure applied by the refrigerant flowing through the refrigerant channel. Therefore,
A thick portion 28 is formed in the lateral direction of the tube 27 having a flat cross section. When the thick portion 28 is formed, the pressure resistance of the tube 27 is improved and the tube 2
7 and the area of the fins in contact with the tube 27 are increased, and the heat exchange area is improved by increasing the heat exchange area.

Further, the tube 27 of this embodiment has a thick portion 28
, And compared with other portions in the longitudinal direction of the tube 27,
A tube insertion portion 29 having a reduced cross-sectional area is formed.

When the thickness of the header pipe is increased in order to ensure the required pressure resistance, the inner diameter of the header pipe is reduced, and the width of the tube insertion hole formed for connecting the tube and the header pipe is reduced. Become.

That is, when the tube insertion hole becomes smaller, the width of the tube connected and connected by inserting the tube end into the tube insertion hole becomes narrower, and the amount of heat transfer to the fin mounted between the tubes becomes smaller. This causes a problem that the heat exchange rate is reduced.

In the tube 27 of this example, at the longitudinal end of the tube 27, the thick portions 28 formed at both ends in the lateral direction of the tube are cut and substantially coincide with the tube insertion holes formed in the header pipe. A tube insertion portion 29 having a cross-sectional shape is formed. Therefore, even if the tube insertion hole is reduced by increasing the thickness of the header pipe, the width of the tube 27 in the lateral direction is not changed with the narrowing of the tube insertion hole. The tube 27 can be communicatively connected to the header pipe.

Further, since the tube 27 can be assembled to the header pipe while keeping the contact area with the fins without changing the width of the tube 27 in the lateral direction, the heat exchanger efficiency is improved.

In the tube 27 of this embodiment, since the thick portion 28 is formed, the required pressure resistance is secured, and the heat exchanger can be made of aluminum or an aluminum alloy at a low cost and light weight.

[0086]

As described above, the present invention provides a heat exchange tube having a refrigerant flow path having a circular cross section, a fin abutting on the tube, and a communicative connection with the tube so as to supply and receive the refrigerant. In the heat exchanger having a header pipe to perform heat exchange by heat transferred to the tubes and the fins, the heat exchange tube having the refrigerant flow path having a circular cross section has a tube outer shape having a circular cross section, and is mounted between the tubes. The fin is a heat exchanger having a concave portion having substantially the same curvature as the outer shape of the tube, and the concave portion being in contact with the outer shape of the tube having a circular cross section.

When the refrigerant flow path has a circular cross section, the pressure of the flowing refrigerant is uniformly applied to the inside of the refrigerant flow path, so that the pressure resistance of the tube is improved.

When the cross section of the refrigerant flow path of the heat exchange tube is circular and the outer shape of the heat exchange tube is also circular,
The tube volume can be minimized while maintaining a thickness sufficient to withstand the pressure load of the refrigerant flowing through the inside, and the weight increase of the heat exchanger can be prevented.

In the case where the outer shape of the heat exchange tube is circular, a fin having a concave portion having a curvature along the outer shape of the tube is provided.
The contact area between the fin and the tube is enlarged by bringing the concave portion into contact. Therefore, the heat conductivity transmitted from the tube to the fin side increases, and the heat exchange performance of the heat exchanger improves.

Further, if the heat exchanger has fins mounted between the reciprocating tubes, the heat exchange area is enlarged, and the heat exchange performance of the heat exchanger is improved.

A plurality of heat exchangers are arranged in parallel so that the continuous surface of the reciprocating tube and the fins is orthogonal to the direction of the external air flow, and the heat exchangers are connected and connected to form an integrated heat exchanger. With this configuration, the heat exchange area in contact with the external air is enlarged, and the heat exchange performance of the heat exchanger having fins mounted between the reciprocating tubes is improved.

Further, when the heat exchanger tubes and the fins are alternately laminated to form a heat exchanger in which each tube end is connected to a pair of header pipes, a heat exchange area composed of tubes and fins is provided. And the heat exchange performance of the heat exchanger is improved.

Also, the longitudinal direction of the laminated tubes and fins is perpendicular to the ventilation direction of the external air.
When a plurality of heat exchangers are arranged in parallel, and the heat exchanger is configured such that the header pipes of each heat exchanger are connected and connected to each other, the heat exchange area in contact with the external air is increased,
The heat exchange performance of the heat exchanger is improved.

Further, the header pipe used in the heat exchanger has a circular refrigerant flow section, so that the refrigerant pressure is uniformly applied to the header pipe and the pressure resistance of the header pipe is improved.

When the header pipe is designed to have a refrigerant flow path diameter not exceeding 10 mm and the header pipe is designed to have a wall thickness not exceeding 5 mm, the minimum pressure is required to secure the required pressure resistance. With such a value, the header pipe can be formed, and the increase in weight for securing the pressure resistance is limited, so that the on-board layout of the heat exchange is improved.

In addition, since the required pressure resistance is ensured and the structure is designed to prevent weight increase, it is possible to form a tube or a header pipe using aluminum or an aluminum alloy. Can be formed at low cost.

Further, even when a refrigerant in a gas state requiring high pressure resistance, for example, CO ₂ is used in a refrigeration cycle, an increase in weight for securing pressure resistance and deterioration of layout properties are prevented, and The heat exchanger of the invention is used.

[0098]

[Brief description of the drawings]

FIG. 1 is a front view showing a heat exchanger in which fins are mounted between meandering reciprocating tubes according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a fin and a tube according to a specific example of the present invention.

FIG. 3 is a perspective view showing a heat exchanger in which a plurality of fins and tubes shown in FIG. 1 are arranged in parallel according to a specific example of the present invention.

FIG. 4 is a perspective view showing a schematic configuration of a heat exchanger in which fins and tubes are alternately stacked between a pair of header pipes according to a specific example of the present invention.

5 is a perspective view showing a heat exchanger according to a specific example of the present invention, in which a plurality of heat exchangers shown in FIG. 4 are arranged in parallel, and the heat exchangers are connected and connected to be integrated. .

FIG. 6 is a perspective view showing a heat exchange tube according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Tube 2a Refrigerant flow path 3 Fin 3a Recess 4 Louver 5 Header pipe 6 Header pipe 10 Heat exchanger 11 Heat exchanger 12 Tube 13 Fin 13a Recess 14 Header pipe 14a Refrigerant flow path 15 Header pipe 15a Refrigerant flow path Reference Signs List 16 heat exchanger 17 heat exchanger 18 header pipe 19 header pipe 20 header pipe 21 header pipe 22 piping 23 heat exchanger 24 tube 25 tube 26 tube 27 tube 27a refrigerant flow path 28 thick part 29 tube insertion part

Claims (10)

[Claims] 1. A heat exchange tube having a refrigerant flow path having a circular cross section, a fin abutting on the tube, and a header pipe connected to and connected to the tube to transmit and receive a refrigerant, and In a heat exchanger that performs heat exchange by means of transmitted heat, the heat exchange tube having the refrigerant flow path having a circular cross section has a tube outer shape with a circular cross section, and fins mounted between the tubes have substantially the same shape as the tube outer shape. A heat exchanger comprising a concave portion having a curvature, wherein the concave portion is abutted along a tube outer shape having a circular cross section. 2. The heat exchanger according to claim 1, wherein fins are mounted between the reciprocating tubes. 3. The heat exchange according to claim 1, wherein the tubes and the fins are alternately laminated to form a multi-layer, and each tube end is connected to a pair of header pipes. vessel. 4. A fin is mounted between the reciprocating tubes,
In the heat exchanger in which the tube end is connected to the header pipe, a plurality of heat exchangers are arranged in parallel so that the continuous surface of the reciprocating tube and the fins is orthogonal to the direction of ventilation of the external air. 3. The heat exchanger according to claim 2, wherein the heat exchangers are connected and integrated. 5. The heat exchanger in which the tubes and the fins are alternately stacked, and the tube ends are connected to a pair of header pipes, the longitudinal direction of the stacked tubes and fins relative to the ventilation direction of the external air. 4. The heat exchanger according to claim 3, wherein a plurality of heat exchangers are arranged in parallel so as to be orthogonal to each other, and header pipes of the heat exchangers are connected and integrated. 6. The heat exchanger according to claim 1, wherein a refrigerant passage of the header pipe has a circular cross section. 7. The header pipe has an inner diameter of 10 mm.
7. The heat exchanger according to claim 6, wherein the diameter of the header pipe does not exceed 5 mm, and the thickness of the header pipe does not exceed 5 mm. 8. The heat exchanger according to claim 1, wherein the tube and the header pipe are formed by molding aluminum or an aluminum alloy. 9. The heat exchanger according to claim 1, wherein the refrigerant flowing into and out of the heat exchanger is in a gaseous state. 10. The method according to claim 1, wherein the refrigerant flowing through the heat exchanger is carbon dioxide (CO ₂ ).
A heat exchanger according to any one of claims 9 to 9.