JP2007285578A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger capable of efficiently blocking the heat transferred from a core portion of a leeward-side heat exchanger to a core portion of a windward-side heat exchanger through a fin, at a refrigerant introduction side of the leeward-side heat exchanger. <P>SOLUTION: The connection fin 4 has a slit 10 between the windward-side heat exchanger 2 and the leeward-side heat exchanger 3, and a ratio of a length L1 of the slit 10 is determined to be longer at a side 3a of introducing a carbon dioxide gas refrigerant of high pressure to the leeward-side heat exchanger 3 with respect to that at an opposite side 3b, thus the transferring of heat at the refrigerant introduction-side 3a of the leeward-side heat exchanger 3 at a high temperature side to the windward-side heat exchanger 2 is effectively blocked, and heat exchanging efficiency between the refrigerant and the air in the windward-side heat exchanger 2 can be improved. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat exchanger configured to pass a plurality of heat exchangers that are stacked on each other by compressing a high-temperature refrigerant.

  In recent years, the frequency of using environmentally better carbon dioxide as a refrigerant in a refrigeration cycle of an air conditioner is increasing. Thus, when carbon dioxide gas is used as the refrigerant, it is necessary to compress the carbon dioxide gas to a higher pressure. Therefore, the compressed refrigerant temperature becomes higher.

  Therefore, since the capacitor | condenser which cools the refrigerant | coolant compressed with the compressor requires high heat exchange efficiency, the state which piled up two heat exchangers mutually in the air flow direction like patent document 1, for example The heat exchange efficiency between the refrigerant and the air, that is, the cooling efficiency can be increased by continuously passing the refrigerant through the heat exchangers on the leeward side and the leeward side.

  That is, in the heat exchanger in which the two heat exchangers described above are stacked, the compressed refrigerant (carbon dioxide gas) is supplied from the leeward heat exchanger to the upwind heat exchanger, and the upwind side The air that has passed through the core portion of the heat exchanger passes through the core portion of the leeward heat exchanger.

  Therefore, when manufacturing such a heat exchanger, there is a method of efficiently manufacturing by integrally heating the fins together in a furnace and brazing them at once.

  Here, since the core portions of both the windward and leeward heat exchangers are close to each other, the fins of both the core portions are formed in a state of being connected to each other and incorporated into the heat exchangers. Yes. For this reason, the high heat of the leeward heat exchanger serving as the refrigerant introduction side is transmitted to the core portion of the windward heat exchanger through the connected fins, and thus the temperature of the refrigerant is reduced. There may be a problem in that the cooling efficiency of the refrigerant flowing through the refrigerant decreases.

  Therefore, it is desirable to separate the fins of the windward side heat exchanger and the fins of the leeward side heat exchanger to prevent heat transfer between these fins. Even in this case, it is desirable to partially connect the fins in consideration of the ease of assembly to both heat exchangers.

As a structure in which both fins are partially connected while being separated as described above, for example, as shown in Patent Document 2, a connection fin is disclosed in which a slit having a connecting portion provided at a predetermined interval is formed between both fins. Yes.
JP 2002-372383 A Japanese Patent Laid-Open No. 2002-168581

  However, in the connection fin formed with the slit disclosed in Patent Document 2, the connection portion provided in the slit simply connects the fins of both heat exchangers and is arranged at a constant interval.

  However, in a leeward heat exchanger into which a high-pressure and high-temperature (carbon dioxide) refrigerant is introduced, the refrigerant introduction side becomes the highest temperature, and the temperature gradually decreases toward the refrigerant discharge side. The refrigerant on the outlet side of the leeward heat exchanger and the inlet side of the leeward heat exchanger has a smaller temperature difference than the inlet side of the leeward heat exchanger and the outlet side of the leeward heat exchanger, and the fins are connected. Even if it does, there is little influence of heat conduction. Therefore, in order to efficiently reduce the heat transferred from the core part of the leeward heat exchanger to the core part of the leeward heat exchanger, the heat transfer is cut off more efficiently on the refrigerant introduction side of the leeward heat exchanger. There is a need to.

  However, when the connecting portions of the slits formed in the connecting fins are at regular intervals, the refrigerant introduction side and the discharge side are thermally shut off under substantially the same conditions, in other words, on the refrigerant introduction side. The heat shutoff efficiency will deteriorate.

  Therefore, the present invention can more efficiently block the heat transferred from the core portion of the leeward heat exchanger to the core portion of the leeward heat exchanger via the fins on the refrigerant introduction side of the leeward heat exchanger, And it aims at obtaining the heat exchanger which can improve the assembly | attachment property in the case of manufacturing simultaneously.

  The present invention relates to a windward side heat exchanger (2) and a leeward side heat exchanger (3) arranged in a state of being overlapped with each other in the air flow direction, and a core portion of the windward side heat exchanger (2) ( 2C) and connecting fins (4) provided on the core part (3C) of the leeward side heat exchanger (3) and connected to each other, and the refrigerant using carbon dioxide gas is sent to the leeward side heat exchanger ( While being supplied from 3) to the windward heat exchanger (2), it passes through the core (2C) of the windward heat exchanger (2) and the core (3C) of the leeward heat exchanger (3). In the heat exchanger (1) for exchanging heat with the air to be circulated, the connecting fin (4) is appropriately lengthened between the upwind heat exchanger (2) and the downwind heat exchanger (3). The slit (10) is formed, and the length ratio of the slit (10) is set on the side (3a) where the refrigerant is introduced into the leeward heat exchanger (3). The most important feature that the is larger than the opposite side (3b).

  According to the present invention, the slits are formed in the connecting fins attached to the respective core portions of the windward side heat exchanger and the leeward side heat exchanger, so that the leeward side heat exchanger into which the carbon dioxide refrigerant is introduced. The heat of the side is suppressed from being transmitted to the windward heat exchanger side via the connecting fins, and the length ratio of the slit is more on the side where the refrigerant is introduced into the leeward heat exchanger than on the opposite side. Therefore, the heat on the refrigerant introduction side of the leeward heat exchanger on the high temperature side is effectively blocked from being transferred to the windward heat exchanger, and the refrigerant and air in the windward heat exchanger are It is possible to improve the heat exchange efficiency.

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

  (First Embodiment) FIG. 1 is an exploded perspective view of a heat exchanger according to this embodiment, FIG. 2 is an exploded perspective view of a connecting fin, and FIG. 3 is an enlarged perspective view of the connecting fin. In addition, below, it applies to the capacitor | condenser used for the refrigerating cycle of a motor vehicle air conditioner, and demonstrates the case where carbon dioxide is used as a refrigerant | coolant of the refrigerating cycle.

  That is, as shown in FIG. 1, the heat exchanger 1 includes an upwind heat exchanger 2 and a leeward heat exchanger 3 that are arranged so as to overlap each other in the flow direction of the air A, and an upwind heat. It is provided with the connection fin 4 provided in the core part 2C of the exchanger 2 and the core part 3C of the leeward heat exchanger 3 and connected to each other. Of course, the windward side heat exchanger 2 is disposed on the upstream side in the flow direction of the air A, and the leeward side heat exchanger 3 is disposed on the downstream side in the flow direction of the air A. The heat exchangers 3 are arranged close to each other in the assembled state of the heat exchanger 1.

  The windward side heat exchanger 2 and the leeward side heat exchanger 3 are configured by providing header tanks 2Tin, 2Tout and 3Tin, 3Tout at both ends of the core portions 2C, 3C in the refrigerant flow direction (left-right direction in the figure). The carbon dioxide refrigerant that has been compressed to a high temperature is introduced from the inlet 3Pin of the inflow side header tank 3Tin of the leeward side heat exchanger 3 and then discharged through the core portion 3C while exchanging heat with the air A. To the side header tank 3Tout, and then introduced into the inflow side header tank 2Tin of the windward side heat exchanger 2, and is sent to the discharge side header tank 3Tout while flowing through the core portion 2C and exchanging heat with the air A. And is discharged from the discharge port 2Pout provided in the header tank 3Tout. Note that an arrow K in FIG. 1 indicates the flow direction of the carbon dioxide refrigerant.

  The core portion 2C of the windward side heat exchanger 2 is disposed between the header tanks 2Tin and 2Tout at both ends at equal intervals in the length direction (vertical direction in the drawing), and the header tanks 2Tin and 2Tout are mutually connected. A plurality of flat tubes 2Ct communicating with each other are provided, and an upwind portion 4F of the connecting fin 4 is loaded between the plurality of tubes 2Ct.

  Moreover, the core part 3C of the leeward side heat exchanger 3 includes a plurality of flat tubes 3Ct that communicate with the header tanks 3Tin and 3Tout at both ends in the same manner as the core part 2C, and are arranged at equal intervals. It is configured by loading the leeward portion 4R of the connecting fin 4 between the plurality of tubes 3Ct.

  The connecting fin 4 is formed in a corrugated shape as shown in FIG. 3 by corrugating the strip-shaped aluminum thin plate 11 shown in FIG. 2, and its overall width W is the width of the core portion 2 </ b> C of the windward heat exchanger 2. W1 (see FIG. 1), the width W2 of the core portion 3C of the leeward heat exchanger 3 (see FIG. 1), and the spacing S between the leeward heat exchanger 2 and the leeward heat exchanger 3 (FIG. 3). The width direction windward side (front side in the figure) is the windward part 4F, and the widthwise leeward side (the other side in the figure) is the leeward part 4R. Yes.

  Here, in the present embodiment, as shown in FIG. 3, the connecting fin 4 is connected between the windward side heat exchanger 2 and the leeward side heat exchanger 3, that is, the leeward portion 4 </ b> F and the leeward portion 4 </ b> R of the connecting fin 4. A slit 10 having an appropriate length is formed between the slit 10 and the length L1 of the slit 10 is set to the side 3a where the refrigerant is introduced into the leeward heat exchanger 3, that is, the side on which the inlet header tank 3Tin is attached. Thus, it is larger than the opposite side 3b, that is, the side to which the discharge side header tank 3Tout is attached. In the case of this embodiment, the side 3a where the refrigerant is introduced into the leeward heat exchanger 3 can be said to be the side where the refrigerant is discharged from the leeward heat exchanger 2, and is the right side in FIG. Yes.

  That is, in this embodiment, in order to increase the ratio of the length L1 of the slit 10 on the side 3a where the refrigerant is introduced into the leeward side heat exchanger 3, the side on which the inflow side header tank 3Tin of the connecting fin 4 is attached is defined. One slit 10 that is sufficiently long as a base end is formed.

  The connection fin 4 is formed by corrugating the strip-shaped aluminum thin plate 11 shown in FIG. 2 to form a wave shape as shown in FIG. 3, but in this embodiment, at the stage of the strip-shaped aluminum thin plate 11. A slit 10 is formed in advance on the connection side of the inflow side header tank 3Tin, and the aluminum thin plate 11 in a state where the slit 10 is formed is corrugated. At this time, the slit 10 is cut out at the end 11e of the aluminum thin plate 11 on the inflow side header tank 3Tin side.

  As shown in FIG. 3, the length L1 of the slit 10 is, for example, in a state in which the connecting fin 4 is corrugated, with respect to the entire length of the connecting fin 4, that is, the entire width L0 of the core portion 2C (see FIG. 1) ( 1/3 · L0) <L1 <(2/3 · L0).

  With the above configuration, according to the heat exchanger 1 of the present embodiment, the slits 10 are formed in the connecting fins 4 that are attached to the core portions 2C and 3C of the windward side heat exchanger 2 and the leeward side heat exchanger 3 in a connected state. , The heat on the leeward heat exchanger 3 side where the carbon dioxide refrigerant is introduced is prevented from being transferred to the leeward heat exchanger 2 side via the connecting fins 4, and the slit 10 is By being formed on the connection side of the inflow side header tank 3Tin, it is possible to effectively block the heat on the refrigerant introduction side of the leeward side heat exchanger 3 that is the high temperature side from being transferred to the upside heat exchanger 2. . Accordingly, since the heat exchange efficiency between the refrigerant and the air can be improved in the windward heat exchanger 2, the cooling efficiency of the refrigerant in the heat exchanger 1 can be increased. The refrigerant on the outlet side of the leeward heat exchanger and the inlet side of the leeward heat exchanger has a smaller temperature difference than the inlet side of the leeward heat exchanger and the outlet side of the leeward heat exchanger, and the fins are connected. Even if it does, since the influence of heat conduction is connected by a small part, the assembly | attachment property in the case of manufacturing simultaneously can be improved.

  (Second Embodiment) FIG. 4 is an exploded perspective view showing another embodiment of a strip-shaped aluminum thin plate forming a connecting fin. In addition, about the same component as the said 1st Embodiment, while attaching | subjecting a common code | symbol, the overlapping description is abbreviate | omitted.

  In the aluminum thin plate 11A of this embodiment, the end 11e on the inflow side header tank 3Tin side of the slit 10 is not cut out, and the end 11e has no influence on heat transfer (and the connection rigidity and connection at the time of molding and assembly) The connecting portion 11c having a minute width w is provided to such an extent that the strength can be maintained, and the slit 10 is closed by the connecting portion 11c.

  Therefore, in the present embodiment, the slit 10 is formed on the inflow side header tank 3Tin side, so that the same effect as that of the first embodiment can be obtained, and the end 11e of the aluminum thin plate 11A is connected by the connecting portion 11c. It is possible to prevent the windward portion 4F and the leeward portion 4R from being separated. For this reason, when forming the connection fin 4 by corrugating the aluminum thin plate 11A, and further, when assembling the connection fin 4 to the core portions 2C and 3C, it is possible to prevent the end 11e side from being displaced. Assembling property can be improved.

  In order to provide the connecting portion 11c in the aluminum thin plate 11A in this case, as shown in FIG. 5, the continuous strip-shaped thin plate 11R in which a plurality of slits 10 are formed at a predetermined interval is cut to obtain individual aluminum thin plates 11A. When forming, the connection part 11c can be easily provided by shifting the cutting position to the adjacent aluminum thin plate 11A side as shown in the figure.

  (Third Embodiment) FIG. 6 is an exploded perspective view showing another embodiment of a strip-shaped aluminum thin plate forming connection fins. Note that the same constituent elements as those in the first embodiment or the second embodiment are given common reference numerals, and redundant description is omitted.

  In the aluminum thin plate 11B of the present embodiment, a plurality of slits 10 are formed, and the lengths La, Lb, Lc,... Of each of the slits 10 are formed longer as going to the inflow side header tank 3Tin side (refrigerant introduction side 3a). It is.

  Therefore, even in the present embodiment, the lengths La, Lb, Lc... Of the plurality of slits 10 formed become longer as going to the inflow side header tank 3Tin side. The heat of the refrigerant introduction side of the leeward heat exchanger 3 to be effectively blocked from being transmitted to the windward heat exchanger 2, and the cooling efficiency of the refrigerant of the heat exchanger 1 can be increased. Separation of the leeward portion 4F and the leeward portion 4R of the connecting fin 4 can be prevented more reliably.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the heat exchange is not limited to the condenser of the refrigeration cycle. The present invention can also be applied to a container.

The disassembled perspective view of the heat exchanger which shows embodiment of this invention. The expansion | deployment perspective view of the connection fin which shows 1st Embodiment of this invention. The expansion perspective view of the connection fin which shows a 1st embodiment of the present invention. The expansion | deployment perspective view of the connection fin which shows 2nd Embodiment of this invention. The top view which shows the state which cuts the formation thin plate of a connection fin from the continuous strip | belt-shaped thin plate which shows 2nd Embodiment of this invention. The expansion | deployment perspective view of the connection fin which shows 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Windward side heat exchanger 2C Core part of windward side heat exchanger 3 Downward side heat exchanger 3C Core part of leeward side heat exchanger 3a Windward side heat exchanger 3 Side where refrigerant is introduced 4 Connecting fin 4F Upward portion of connecting fin 4R Downward portion of connecting fin 10 Slit

Claims (1)

An upwind heat exchanger (2) and a leeward heat exchanger (3) arranged in a state of being stacked on each other in the air flow direction;
Connecting fins (4) provided on the core part (2C) of the windward side heat exchanger (2) and the core part (3C) of the leeward side heat exchanger (3) and connected to each other,
While the refrigerant is supplied from the leeward heat exchanger (3) to the leeward heat exchanger (2), the core (2C) of the leeward heat exchanger (2) and the leeward heat exchanger (3) In the heat exchanger (1) that exchanges heat with the air passing through the core (3C) of
A slit (10) having an appropriate length is formed in the connecting fin (4) between the windward side heat exchanger (2) and the leeward side heat exchanger (3), and the length ratio of the slit (10). Is larger on the side (3a) where the refrigerant is introduced into the leeward heat exchanger (3) than on the opposite side (3b).

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