JP2000130887A - Lamination type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of a temperature distribution in passing air by a method wherein a lower front side tank and a lower rear side tank are partitioned at substantially central part of lengthwise direction of the tanks and each end parts communicate with each other through a header, forming a heat exchanging medium flow passage, while a heat exchanging medium introducing and discharging port unit is formed at the opposite side of the header. SOLUTION: A lower front side tank 11a and a lower rear side tank 11b are provided with partitions 8, 9 at substantially central part of them and are defined into two chambers 27, 28 and two chambers 29, 30 in the lengthwise direction of them respectively. The refrigerant introducing port unit 36 is opened in the chamber 29 of the lower rear side tank 11b and the refrigerant discharging port unit 37 is opened in the chamber 27 of the lower front side tank 11a while the chambers 30, 28 are communicated with each other through a header 31. According to this method, mainly liquid refrigerant is conducted to flow through tubes constituting heat exchanging units 34, 35 opposed to the opening units of the unit to improve a heat exchanging efficiency whereby the generation of a temperature distribution of passing air can be eliminated and the outlet temperature of the air can be unified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated heat exchanger used for, for example, a vehicle air conditioner, and more particularly to a laminated heat exchanger housed and used in a unit.

[0002]

2. Description of the Related Art Conventionally, as a laminated heat exchanger used in a vehicle air conditioner or the like, for example, a conventional heat exchanger 7-12 is disclosed.
A proposal such as that described in Japanese Patent Publication No. 778 has been made. FIG. 6 shows a heat exchanger according to the proposal. In FIG. 6, reference numeral 100 denotes a stacked heat exchanger. The heat exchanger 100 is located downstream with respect to the ventilation direction indicated by the arrow. It has an upper rear tank 101 and a lower rear tank 103, and an upper front tank 105 and a lower front tank 107 positioned upstream with respect to the ventilation direction. The heat exchange medium flow paths 102 and 106 through which the heat exchange medium flows are formed by a plurality of tubes (not shown). By disposing fins (not shown) between the tubes, the downstream heat exchange section 104 is provided. , An upstream heat exchange section 108 is formed. The upper rear tank 1
01 has a refrigerant inlet 109 for introducing a heat exchange medium (refrigerant) in a gas-liquid mixed state into the heat exchanger 100, and a refrigerant outlet 110 is provided in the upper front tank 105. . The tanks 101 and 105 are in communication with each other via a coolant channel 111 formed by, for example, a header.

The upper rear tank 101 has a partition 11 inside.
On the other hand, the upper front tank 105 is partitioned by a partition 113.

In the above-described stacked heat exchanger 100, the refrigerant introduced from the inlet 109 forms a flow path as shown in FIG.
It is to be led out.

However, in the heat exchanger 100 proposed above, for example, the gas-liquid two-phase refrigerant flowing into the tank 101 from the inlet 109 is a refrigerant containing a large amount of liquid phase due to gravity (hereinafter, simply referred to as a liquid refrigerant). ) Easily flows into the flow path 102 communicating with the tank 101 relatively upstream in the refrigerant flow direction. Further, when flowing from the tank 103 into the flow path 102, the liquid refrigerant easily flows into the flow path 102 communicating with the downstream side of the tank 103 in the refrigerant flow direction due to a difference in inertial force. For this reason, as shown in FIG.
In 04, there is a possibility that a high-temperature portion 114 in which a portion having a relatively small flow rate of the liquid refrigerant has a higher temperature than other portions may occur. Further, for the same reason as described above, the upstream heat exchange section 10
8, the high-temperature portion 115 may be generated. In the heat exchanger 100 according to the above proposal, the high-temperature section 11
4 and 115 are substantially the same area, that is, the heat exchange sections 104 and 1
08, there is a possibility that a remarkable temperature distribution may occur in the passing air at the air outlet of the heat exchanger 100.

[0006] In order to solve the above problems, in the proposal described in Japanese Patent Application Laid-Open No. 9-170850, the upstream heat exchange section and the downstream heat exchange section are devised by devising a refrigerant flow path in the heat exchanger. The temperature of the air passing through the heat exchanger is made uniform by shifting the regions of the high-temperature part in the heat exchange part from each other.

[0007]

However, in the actual use phase of the heat exchanger, the heat exchanger usually has a substantially central portion of the facing surface (corresponding to a substantially central portion of the heat exchange portion of the heat exchanger). Part) is housed in a unit in which an opening for passing air is formed. In addition, the opening,
Generally, it is narrower than the heat exchange part of the heat exchanger. For this reason, the wind speed of the passing air passing through the heat exchanging portion is higher in the central portion, but lower at the end portions. As a result, the heat exchange at the central portion becomes insufficient, and the temperature of the passing air at the central portion of the heat exchange portion becomes higher than at the end of the heat exchange portion. Therefore, Japanese Patent Application Laid-Open No. 9-17085
When a high-temperature portion is formed in the opening of the unit as in the proposal described in Japanese Patent Publication No. 0, heat exchange of passing air is insufficient, and it is difficult to prevent the occurrence of a temperature distribution. In other words, the proposal described in Japanese Patent Application Laid-Open No. 9-170850 can solve the temperature distribution when the wind speed of the air passing through the heat exchange section is uniform over the entire area of the heat exchange section. If the wind speed of the passing air becomes uneven, the temperature distribution may not be effectively eliminated.

An object of the present invention is to provide a high-performance heat exchanger capable of preventing the occurrence of a temperature distribution of passing air in an actual use state.

[0009]

In order to solve the above-mentioned problems, a laminated heat exchanger according to the present invention has tubes and fins alternately laminated, and is provided at an upper end of the tube at an upstream side with respect to a ventilation direction. A certain upper front tank and an upper rear tank located downstream are formed, and at the lower end of the tube,
In the laminated heat exchanger in which the lower front tank and the lower rear tank are formed, the lower front tank and the lower rear tank are partitioned at substantially the center in the longitudinal direction of the tank,
One end of the lower front tank and one end of the lower rear tank communicate with each other via a header forming a heat exchange medium flow path, and a heat exchange medium introduction / exit portion is formed on the side opposite to the header.

It is preferable to provide a side tank for introducing and discharging a heat exchange medium in the outermost layer of the laminated portion formed by the tubes and the fins. In the present invention, since the heat exchange medium introduction / exit portion is formed in the lower front tank and the lower rear tank, if a side tank is provided, the side tank can communicate with the lower front tank and the lower rear tank. Good.

In the above-described stacked heat exchanger,
Since a large amount of liquid refrigerant flows through the tube forming the heat exchange part in the substantially central part of the heat exchange part, that is, the area corresponding to the opening of the unit, a high-temperature part is formed in the central part. There is no. For this reason, the heat exchange efficiency in the above-mentioned central portion where the wind speed of the passing air is high can be improved, so that the temperature distribution of the passing air after passing through the heat exchanger can be eliminated and the temperature can be made uniform. Further, in the heat exchanger as described above, the high-temperature portion is formed at the end of the heat exchange portion of the heat exchanger, but this portion is blocked by the unit during use, and it is difficult for air to pass through. Since it was a part, there was a risk of frost formation when the refrigerant temperature in the heat exchanger was low. However, the formation of a high-temperature part in this part can eliminate the possibility of frost formation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 to 5
Shows a heat exchanger according to an embodiment of the present invention.
In the figure, reference numeral 1 denotes a heat exchanger. Heat exchanger 1
Shows a laminated heat exchanger in which tubes 2 and fins 3 are alternately laminated. Side plates 12 and 13 are provided at both ends of the laminated portion formed by the tubes 2 and the fins 3. On the side plate 12 side, a side tank 4 that forms a flow path for introducing and discharging a heat exchange medium (refrigerant) is provided. The side tank 4 is provided with a flange 5 for introducing and discharging the refrigerant, and an expansion valve 14 is connected to the flange 5.

The tube 2 is formed by joining forming plates 6 and 7 as shown in FIG. The connecting plates 15, 16, 17, 1 are formed on the forming plate 6 (7).
8 (19, 20, 21, 22) are formed. Also, the bulging portions 23, 24 (2
5, 26) are formed. In order to maintain the internal pressure strength of the tube, ribs that contact each other may be formed, or another member such as an inner fin may be provided in the bulging portion. Then, the connecting plates 15 are connected to the adjacent tubes 2 by joining the forming plates 6 and 7, and the connecting convex portions 15 and 19, 16 and 20, 17 and 21,
By connecting 18 and 22, an upper tank 10 and a lower tank 11 are formed at the upper and lower ends of the tube 2. The upper tank 10 includes an upper front tank 10a located on the upstream side in the ventilation direction and an upper rear tank 10b located on the downstream side. Also, the lower tank 11
Lower front tank 11a located upstream with respect to the ventilation direction
And a lower rear tank 11b located on the downstream side. The upper front tank 10a and the lower front tank 11a
Are communicated with each other through a refrigerant channel 32 formed by the bulging portions 24 and 26. The upper rear tank 10b and the lower rear tank 11b are connected to each other via a refrigerant flow path 33 formed by the bulging portions 23 and 25. And channel 3
2, the fin 3, the tanks 10a and 11a form an upstream heat exchange section 34, and the flow path 33, the fin 3,
A downstream heat exchange section 35 is formed by the tanks 10b and 11b.

Lower front tank 11a, lower rear tank 11b
Partitions 8 and 9 are provided substantially at the center of the tank, and the inside of the tanks 11a and 11b is partitioned into two chambers in the longitudinal direction. The lower front tank 11a is provided in two chambers 27 and 28,
The inside of the lower rear tank 11b is divided into two chambers 29 and 30. A refrigerant inlet 36 is opened in the chamber 29 of the lower rear tank 11b, and a refrigerant outlet 37 is opened in the chamber 27 of the lower front tank 11a. The room 30 and the room 28 are communicated via a header 31.

In the laminated heat exchanger 1 of this embodiment, the lower rear tank 11 is connected to the expansion valve 14 through the flange 5 and the inlet side flow path of the side tank 4 through the inlet 36.
The refrigerant introduced into the chamber 29 of b is connected to the tube 2 communicating with the chamber 29 → the tank 10b → the tube 2 communicating the tank 10b with the chamber 30 → the chamber 30 → the header 31 → the chamber 28 → the chamber 28 and the tank 10a. The tube 2 → the tank 10a → the tube 2 connecting the tank 10a and the chamber 27 → the chamber 27 → the outlet port 37 → the heat exchanger 1 is circulated in the same route as the outlet side flow path of the side tank 4. (Fig. 3).

The refrigerant decompressed by the expansion valve 14 is in a gas-liquid mixed state in which a gas-phase refrigerant and a liquid-phase refrigerant are mixed. For this reason, the refrigerant flowing into the chamber 29 has a large amount of gas refrigerant flowing into the tube 2 communicating with the vicinity of the inlet 36 of the chamber 29 due to a difference in inertia force, and a tube communicating with a position distant from the inlet 36. A large amount of liquid refrigerant flows into 2. The same phenomenon also appears in the flow path from the chamber 28 to the upper front tank 10a. Further, the refrigerant flowing into the tank 10b flows out into the tube 2 communicating the tank 10b and the chamber 30, but in this case, the liquid refrigerant flows into the tube 2 communicating with the upstream side of the refrigerant flow path due to gravity. A large amount of gas refrigerant flows out into the tube 2 communicating with the downstream side of the refrigerant flow path. A similar phenomenon is seen in tank 1
It also appears in the flow path from 0a to the chamber 27. Therefore, the upstream heat exchange unit 34 and the downstream heat exchange unit 35
The high temperature parts 38, 39, 40, 41
Is formed.

Incidentally, when the heat exchanger 1 is normally used (for example, when it is incorporated in a vehicle air conditioner).
Are housed in a unit 44 having openings 42 and 43 for air passage formed on opposite surfaces. The openings 42 and 43 are smaller than the heat exchange parts 34 and 35 of the heat exchanger 1 as shown in FIG. For this reason, the wind speed of the passing air passing through the heat exchanger 1 varies in a direction perpendicular to the wind direction. That is, the opening 42,
The wind speed increases at substantially the central portions of the heat exchange portions 34 and 35 corresponding to 43, while the wind speed decreases at the end portions away from the central portion. For this reason, the heat exchange of the passing air passing through the central portion becomes insufficient, and the temperature tends to be higher than the passing air at the end portion.

However, in the heat exchanger 1 of this embodiment, the liquid refrigerant mainly flows through the tubes 2 constituting the heat exchange portions 34 and 35 corresponding to the openings 42 and 43 of the unit 44. , The high temperature parts 38, 39,
Since 40 and 41 are not formed, the air passing through the central portion can be efficiently heat-exchanged. Therefore, heat exchanger 1
Can eliminate the temperature distribution of the passing air at the outlet portion, and can achieve uniform blowing temperature.

When the heat exchanger 1 is housed in the unit 44, the ends of the heat exchangers 34 and 35 are
4, the end portion has a low velocity of the passing air, so that frost formation is likely to occur. However, in this embodiment, a high-temperature portion is formed at the end portion. Also, frost formation can be prevented.

[0020]

As described above, in the case of the laminated heat exchanger of the present invention, the liquid refrigerant mainly flows through the tubes constituting the heat exchange section corresponding to the opening of the unit, and the heat exchange section is provided. Since the heat exchange efficiency of the air can be improved, the temperature distribution of the passing air can be eliminated and the blowing temperature can be made uniform.

[Brief description of the drawings]

FIG. 1 is a perspective view of a laminated heat exchanger according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a tube of the laminated heat exchanger of FIG.

FIG. 3 is a perspective view illustrating a flow path of a refrigerant in the stacked heat exchanger of FIG. 1;

FIG. 4 is a perspective view showing a position of a high temperature part of a heat exchange part of the stacked heat exchanger of FIG.

FIG. 5 is a perspective view showing a state in which the stacked heat exchanger of FIG. 1 is housed in a unit.

FIG. 6 is a perspective view showing a refrigerant flow path of a heat exchanger according to a conventional proposal.

FIG. 7 is a perspective view showing a position of a high temperature part of a heat exchange part of the heat exchanger of FIG.

[Explanation of symbols]

Reference Signs List 1 laminated heat exchanger 2 tube 3 fin 4 side tank 5 flange 6, 7 forming plate 8, 9 partition 10 upper tank 10a upper front tank 10b upper rear tank 11 lower tank 11a lower front tank 11b lower rear tank 12, 13 side plate 14 expansion valve 15, 16, 17, 18, 19, 20, 21, 22 connecting projection 23, 24, 25, 26 bulging part 27, 28, 29, 30 chamber 31 header 32, 33 refrigerant flow Path 34 Upstream heat exchange section 35 Downstream heat exchange section 36 Refrigerant inlet 37 Refrigerant outlet 38, 39, 40, 41 High temperature section 42, 43 Opening 44 unit

Claims (2)

[Claims] 1. A tube and a fin are alternately laminated,
At the upper end of the tube, an upper front tank on the upstream side with respect to the ventilation direction and an upper rear tank on the downstream side are formed, and at the lower end of the tube, a lower front tank and a lower rear tank are provided. In the laminated heat exchanger to be formed, the lower front tank and the lower rear tank are partitioned at a substantially central portion in the longitudinal direction of the tank, and one end of the lower front tank and the lower rear tank are flowed through a heat exchange medium flow. A stacked heat exchanger characterized in that the heat exchanger communicates with a header forming a passage and a heat exchange medium introduction / exit portion is formed on the side opposite to the header. 2. A side tank for introducing and discharging a heat exchange medium is provided on an outermost layer of a laminated portion formed by the tubes and fins, and the side tank is communicated with a lower front tank and a lower rear tank. The stacked heat exchanger of claim 1, wherein: