JPH10122704A - Heat exchanger of air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve performance without changing the sectional area of a heat transfer pipe or the number of passes, in the heat exchanger of an air conditioner using a refrigerant having a saturation pressure of 2500kPa or over at 50 deg.C. SOLUTION: The indoor heat exchanger 5 which constitutes the freezing cycle of an air conditioner has heat transfer pipes 21-24 where refrigerant flows and a large number of plate-shaped fins 20a-20c. Inside all or part of the heat transfer pipes 21-24, heat transfer accelerating members (spacers S1) having the so-called 'twist tape' form are inserted. The heat transfer on the refrigerant side (inside of the pipe) of the heat transfer pipes 21-24 at large is accelerated by causing the forced secondary flow (radial flow) in the refrigerant mainly within the heat transfer pipes 21-24 by the heat transfer accelerating member S1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger for an air conditioner having a heat transfer tube through which a refrigerant flows.
The present invention relates to a heat exchanger whose performance is improved by promoting heat transfer on the refrigerant side of a heat transfer tube.

[0002]

2. Description of the Related Art Conventionally, an indoor heat exchanger of an air conditioner as shown in FIGS. 17 and 18 has been used. 17 and 18, the indoor heat exchanger 5 '
A main indoor heat exchanger 8 including a first heat exchanger 8a and a second heat exchanger 8b, and a second heat exchanger 8 of the main indoor heat exchanger 8;
b) and an auxiliary heat exchanger 9 disposed above b.

[0003] The main indoor heat exchanger 8 has a first
Fin 2 constituting heat exchanger 8a and second heat exchanger 8b
0a and the fins 20b, which have a large number of plate-like fins 20a and 20b stacked at intervals.
On the other hand, the auxiliary heat exchanger 9 is a fin 2 of the main indoor heat exchanger 8.
It has a large number of plate-like fins 20c separated from 0a and 20b. In FIG. 18, the fins 20a and the fins 20b are shown without any particular distinction.

The indoor heat exchanger 5 ′ is a heat transfer tube 21 to 24 through which a refrigerant flows. The heat transfer tubes 21 to 23 forming the main indoor heat exchanger 8 and a transfer tube forming the auxiliary heat exchanger 9. A heat tube 24 is provided. Here, in FIGS. 17 and 18, arrows indicate the flow of the refrigerant during the heating operation, and reference numerals I and O indicate the inlet and the outlet of the refrigerant in that case, respectively. In the heat transfer tubes 21 to 24, the flow path during the heating operation is such that the flow paths (heat transfer pipes 21 and 22) branched into two at the inlet I of the refrigerant join at the junction J to form one flow path. The heat transfer tubes have a so-called 2-1 pass configuration (a 1-2 pass configuration based on the cooling operation) as the heat transfer tubes (heat transfer tubes 23 and 24) reaching the outlet O.

[0005] The heat transfer tubes 21 to 24 of each pass are respectively connected to a plurality of straight tube portions 31 to 34 penetrating the plate-like fins 20a to 20c and end portions of the adjacent straight tube portions 31 to 34. And a plurality of U-shaped connecting pipes (return bends) 41 to 44 for connecting them.

Although the example of the indoor heat exchanger 5 'of the air conditioner has been described with reference to FIGS. 17 and 18, the basic structure of the outdoor heat exchanger is the same as that of the indoor heat exchanger. It is.

In a heat exchanger of an air conditioner having a heat transfer tube having a plurality of paths through which a refrigerant flows as described above, the performance of the heat exchanger can be improved by increasing the heat transfer coefficient on the refrigerant side (inside the tube). Various means are used. As one of such means, a refrigerant having a saturation pressure at 50 ° C. of 2500 kilopascals (kPa) or more (for example,
In a heat exchanger of an air conditioner using a mixed refrigerant of R32 / 125), the cross-sectional area (tube diameter) and the number of passes (the number of branches of a flow path) of the heat transfer tube are reduced, so that the flow rate of the refrigerant in the heat transfer tube Japanese Patent Application No. 7-54381 discloses a method for improving the heat transfer coefficient on the refrigerant side (inside the pipe) by increasing the temperature.

[0008]

However, such a heat exchanger for an air conditioner has the following problems. That is, for example, the straight pipe portions 31 to 34 of the heat transfer tubes 21 to 24 and the U-shaped connecting pipes (return bends) 41 to 41
44 is generally joined by brazing. However, if the diameter of the heat transfer tubes 21 to 24 is reduced, the brazing becomes difficult, the productivity is deteriorated, and problems such as clogging of the brazing easily occur.

In a heat exchanger having a heat transfer tube having a plurality of paths (particularly, a type in which a flow path is branched in the heat exchanger), generally, the smaller the number of passes, the more the flow rate when used as an evaporator. The branch point of the road is on the downstream side. And
When the number of passes is reduced in such a heat exchanger, when used as an evaporator, the flow state of the refrigerant at the branch point changes to an annular flow (the liquid refrigerant is (Flow in a state biased toward the inner wall surface side of the heat transfer tube). For this reason, the branch flow of the refrigerant at the branch point becomes non-uniform, and on the contrary, the performance of the heat exchanger may be reduced.

The present invention has been made in view of the above points, and is intended to provide a heat exchanger for an air conditioner using a refrigerant having a saturation pressure of 50 ° C. of 2500 kilopascals (kPa) or more. An object is to improve the performance of a heat exchanger without changing the cross-sectional area or the number of passes.

[0011]

A first means is a heat exchanger of an air conditioner having a heat transfer tube through which a refrigerant flows.
A heat transfer promoting member for using a refrigerant having a saturation pressure at 50 ° C. of 2500 kilopascals (kPa) or more and changing a flow state of the refrigerant in the heat transfer tube to promote heat transfer. Is inserted.

According to the first means, heat transfer on the refrigerant side of the heat transfer tube can be promoted by the heat transfer promoting member inserted into the heat transfer tube.

According to a second aspect, in the first aspect, the heat transfer promoting member has a twisted tape shape.

[0014] According to the second means, in the first means, the heat transfer promoting member having a twisted tape shape mainly causes a forced secondary flow of the refrigerant in the heat transfer tube, thereby transferring the heat. Heat transfer on the refrigerant side of the heat tube can be promoted.

According to a third aspect, in the first aspect, the heat transfer promoting member has a coil spring shape.

According to the third means, in the first means, the heat transfer promoting member having a coil spring shape is used.
By mainly disturbing the flow of the refrigerant in the heat transfer tube, heat transfer on the refrigerant side of the heat transfer tube can be promoted.

In a fourth aspect, the heat transfer tube according to any one of the first to third means is provided only in a portion of the heat transfer tube on the downstream side in the refrigerant flow direction when the heat exchanger is a condenser. A heat promoting member is inserted.

According to the fourth means, in any one of the first to third means, the heat transfer promoting member is provided at the downstream side in the refrigerant flow direction when the heat exchanger is a condenser. Heat transfer on the refrigerant side of the heat tube is promoted. Similarly, the pressure loss at the upstream side (downstream in the refrigerant flow direction when the heat exchanger becomes an evaporator) is smaller than when the heat transfer promoting member is inserted. Thereby, the performance of the heat exchanger can be improved while balancing the case where the heat exchanger becomes an evaporator and the case where the heat exchanger becomes a condenser.

The fifth means is that in any one of the first to third means, when the heat exchanger is a condenser, the heat transfer tube has a multi-pass structure having one or more junctions. The heat transfer tube, wherein the heat transfer promoting member is inserted only in a portion downstream of all or a part of the junction in the refrigerant flow direction when the heat exchanger is a condenser. It is.

According to the fifth means, in any one of the first to third means, in the flow direction of the refrigerant in the case where the heat exchanger serves as a condenser, a portion downstream of all or a part of the merging portion is provided. In part, the heat transfer enhancing member enhances the heat transfer of the low-dryness or single-phase refrigerant. Similarly, the pressure loss at the upstream side (downstream in the refrigerant flow direction when the heat exchanger becomes an evaporator) is smaller than when the heat transfer promoting member is inserted. Thereby, the performance of the heat exchanger can be improved while balancing the case where the heat exchanger becomes an evaporator and the case where the heat exchanger becomes a condenser.

The sixth means includes an indoor heat exchanger and an outdoor heat exchanger, and one of the indoor heat exchanger and the outdoor heat exchanger is any one of the first to fifth means. It is an air conditioner characterized by being a heat exchanger.

According to the sixth means, the heat transfer on the refrigerant side of the heat transfer tube of one of the heat exchangers is promoted according to the difference in various conditions between the indoor heat exchanger and the outdoor heat exchanger. It can be facilitated by a member. As a result, the performance of both the indoor heat exchanger and the outdoor heat exchanger can be improved in a well-balanced manner.

[0023]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 16 are diagrams showing an embodiment of a heat exchanger of an air conditioner according to the present invention. In the embodiments of the present invention shown in FIGS. 1 to 16, the same components as those of the conventional example shown in FIGS.

[First Embodiment] First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, the air conditioner includes a refrigeration cycle in which a compressor 1, a four-way valve 2, an outdoor heat exchanger 3, an expansion valve 4, and an indoor heat exchanger 5 are sequentially connected by refrigerant piping. The indoor heat exchanger 5 includes a main indoor heat exchanger 8 and an auxiliary indoor heat exchanger 9. Also, in FIG.
Reference numeral 7 denotes an outdoor fan and an indoor fan, respectively.

In FIG. 1, the solid arrows indicate the flow of the refrigerant during the cooling operation, and the dashed arrows indicate the flow of the refrigerant during the heating operation. During the cooling operation, the outdoor heat exchanger 3 functions as a condenser, and the indoor heat exchanger 5 functions as an evaporator. On the other hand, during the heating operation, on the contrary, the outdoor heat exchanger 3 becomes an evaporator and the indoor heat exchanger 8
Becomes a condenser.

Here, a refrigerant having a saturation pressure at 50 ° C. of 2500 kilopascals (kPa) or more is used as the refrigerant. As such a refrigerant, for example, R32
(CH ₂ F ₂ : difluoroethane) and R125 (CHF
_2- CF ₃ : pentafluoroethane) has a synthetic composition of 80
% Or more, R143a (CF ₃ —CH ₃ : 1,1,1)
1-trifluoroethane) and R125 have a synthetic composition of 80
% Or more, and those with a composition of R32 of 45% or more.
There is a refrigerant.

Next, as shown in FIG. 2, the air conditioner includes an outdoor unit A and an indoor unit B. Among them, the outdoor unit A incorporates the compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the expansion valve 4, and the outdoor fan 6 shown in FIG. 1, and the indoor unit B is the indoor unit shown in FIG. Heat exchanger 5 and indoor fan 7
Has a built-in. The outdoor unit A and the indoor unit B are connected by a connecting pipe C having a gas-side connecting pipe C1 and a liquid-side connecting pipe C2 (see FIG. 1).

Next, as shown in FIG. 3, the indoor unit B has a front panel 15 that covers the indoor heat exchanger 5 and the indoor fan 7. The inverted V-shaped main indoor heat exchanger 8 of the indoor heat exchanger 5 includes a first heat exchanger 8a located in front of the indoor fan 7 and a second heat exchanger 8a located behind and above the indoor fan 7. And a heat exchanger 8b. Also,
The auxiliary heat exchanger 9 is disposed on the upper side of the second heat exchanger 8b. Further, the front panel 15 is provided with a front suction grill 12 corresponding to the first heat exchanger 8a, and a top suction grill 13 corresponding to the auxiliary indoor heat exchanger 9 and the second heat exchanger 8b (see FIG. 2). (See FIG. 2). An outlet 14 is provided at a front lower portion of the front panel 15, and the outlet 14 is provided with a left and right wind direction plate 10 and a vertical wind direction plate 11.

The rotation of the indoor fan 7 allows the indoor air to be sucked from the front suction grill 12 and the top suction grill 13. Among them, the indoor air sucked from the front suction grill 12 is supplied to the first heat exchanger 8.
a, the indoor air sucked from the upper surface suction grill 13 passes through the auxiliary indoor heat exchanger 9 and the second heat exchanger 8b, and is both blown out from the outlet 14 as conditioned air.

Next, as schematically shown in FIGS. 4 and 5, the main indoor heat exchanger 8 comprises fins 20a and 20b constituting the first heat exchanger 8a and the second heat exchanger 8b, respectively. And has a large number of plate-like fins 20a and 20b stacked at intervals. On the other hand, the auxiliary heat exchanger 9 has many plate-like fins 20c separated from the fins 20a and 20b of the main indoor heat exchanger 8. In FIG. 5, the fins 20a and the fins 20b are shown without distinction.

The indoor heat exchangers 5 are heat transfer tubes 21 to 24 through which a refrigerant flows. The heat transfer tubes 21 to 23 forming the main indoor heat exchanger 8 and the heat transfer tubes forming the auxiliary heat exchanger 9. 24. During the heating operation, the heat transfer tubes 21 to 24 are combined into one flow passage (heat transfer tubes 21, 22) at the junction J on the way to form a single flow passage (the heat transfer tubes 21 and 22). The heat transfer tubes have a so-called 2-1 pass configuration (a 1-2 pass configuration based on the cooling operation) as the heat transfer tubes 23 and 24) and reach the outlet O.

The heat transfer tubes 21, 22, 23,
Reference numeral 24 denotes a number of the plate-like fins 20a to 20c, respectively.
And a plurality of U connecting the end portions of the adjacent straight pipe portions 31 to 34 with the end portions of the adjacent straight pipe portions 31 to 34
-Shaped connecting pipe (return bend) 41, 42, 43, 44
And

Next, as shown in FIG.
Inside the entirety of the heat transfer tubes 21 to 24, a heat transfer promoting member (spacer) S1 having a so-called “Twisted Tape” shape is inserted. The heat transfer promoting member S1 has a shape in which a thin flat plate (tape) extending in the axial direction of the heat transfer tubes 21 to 24 is twisted around its axis, and both side edges 100 have inner walls of the heat transfer tubes 21 to 24. Is almost in contact with. This heat transfer promoting member S1
The flow of the refrigerant inside the heat transfer tubes 21 to 24 is forcibly changed into a spiral shape.

Next, the operation of the present embodiment having such a configuration will be described. According to the present embodiment, the heat transfer promoting member S1 mainly changes the flow of the refrigerant in the heat transfer tubes 21 to 24 in a helical manner to cause a forced secondary flow (radial flow). Heat transfer (forced convection heat transfer) on the refrigerant side (inside of the tubes) of the entire heat transfer tubes 21 to 24 can be promoted. As a result, in a heat exchanger of an air conditioner using a refrigerant having a saturation pressure at 50 ° C. of 2500 kilopascals (kPa) or more, the performance of the heat exchanger is improved without changing the cross-sectional area of the heat transfer tube or the number of passes. Can be done.

Next, a modification of this embodiment will be described with reference to FIGS. In the first modification, a heat transfer promoting member S1 'shown in FIG. 7 is used instead of the heat transfer promoting member S1 shown in FIG. As shown in FIG. 7, the heat transfer promoting member S1 'is formed by forming a large number of small holes 110 in the heat transfer promoting member S1. In the second modification, a heat transfer promoting member S1 ″ shown in FIG. 8 is used instead of the heat transfer promoting member S1. As shown in FIG.
The heat transfer promoting member S1 ″ is formed by engraving a large number of cuts 120 extending from both side edges 100 of the heat transfer promoting member S1 to the inside in the radial direction of the heat transfer tubes 21 to 24. In this case, heat transfer is promoted. The member S1 ″ is formed by cutting a large number of cuts 120 in a thin plate (tape) -like material in advance, and twisting the cuts into the “twisted tape” shape, so that adjacent cuts 120 are separated by the cuts 120. It is preferable that the rectangular portions 122 be shaped so as to be slightly different from each other.

According to these modifications, the heat transfer promoting member S
1 ′, S1 ″ causes a forced secondary flow in the refrigerant inside the heat transfer tubes 21 to 24, and induces mixing and turbulence of the flow of the refrigerant, so that the heat on the refrigerant side of the heat transfer tubes 21 to 24 is generated. Communication can be further promoted.

[Second Embodiment] Next, FIGS.
The second embodiment of the present invention will be described below. In the present embodiment, a heat transfer promoting member S2 shown in FIG. 9 is used instead of the heat transfer promoting member S1 of the first embodiment, and other configurations are the same as those of the first embodiment shown in FIGS. This is similar to the first embodiment.

As shown in FIG. 9, the heat transfer promoting member S2 of the present embodiment has a coil spring shape such that its outer peripheral portion 130 substantially contacts the inner walls of the heat transfer tubes 21 to 24.
The cross-sectional shape of the wire constituting the heat transfer promoting member S2 is:
In addition to the semicircle shown in FIG. 9, the shape may be a square, a circle, a triangle, or the like shown in FIGS.

Next, the operation of the present embodiment having such a configuration will be described. According to the present embodiment, the heat transfer promoting member S2 having a coil spring shape mainly disturbs the flow of the refrigerant in the heat transfer tubes 21 to 24 and suppresses the development of the temperature boundary layer. Heat transfer on the entire refrigerant side can be promoted. This allows 50
In a heat exchanger of an air conditioner that uses a refrigerant having a saturation pressure of 2,500 kPa (kPa) or more, the performance of the heat exchanger can be improved without changing the cross-sectional area or the number of passes of the heat transfer tubes.

Third Embodiment Next, FIG. 11 and FIG.
2, a third embodiment of the present invention will be described. As shown in FIGS. 11 and 12, in the present embodiment, among the heat transfer tubes 21 to 24 of the indoor heat exchangers 5A to 5C, the refrigerant flow direction when the indoor heat exchangers 5A to 5C serve as condensers ( FIG.
The heat transfer promoting members S1 to S are provided only on the downstream side (in the direction of the arrow in FIG. 1 and FIG. 12) (the black portion in FIG. 11 and FIG. 12).
The difference from the first and second embodiments is that 1 ″ and S2 are inserted, and the other configuration is the same as the first and second embodiments shown in FIGS. 1 to 10.

First, the heat exchanger 5A shown in FIG. 11 has a straight pipe section 31, which is closest to the inlet I side among the heat transfer pipes 21, 22.
32, the heat transfer promoting members S1 to S1 ″ and S2 are not inserted, and the heat transfer promoting members S1 to S1 ″ and S2 are provided on the downstream side of the heat transfer tubes 21 and 22 and inside the heat transfer tubes 23 and 24. S
1 ″ and S2 are inserted.

Next, in the heat exchanger 5B shown in FIG. 12 (a), the heat transfer promotion members S1 to S1 ″ and S2 are inserted into the heat transfer tubes 21 and 22 upstream of the junction J. Without
Only inside the heat transfer tubes 23, 24 downstream of the junction J,
Heat transfer promoting members S1 to S1 ″, S2 are inserted.

Further, in the heat exchanger 5C shown in FIG. 12B, the heat transfer promoting member S1 is further extended to the intermediate portion of the heat transfer tube 23 further downstream than the case of the heat exchanger 5B shown in FIG. ~ S1 ″ and S2 are not inserted and the heat transfer tubes 23
Only on the downstream side of the middle part of and in the heat transfer tube 24,
Heat transfer promoting members S1 to S1 ″ and S2 are inserted.

Next, the operation of the present embodiment having such a configuration will be described. According to the present embodiment, the heat transfer promoting members S1 to S1 ″ and S2 are provided at the downstream side of the heat transfer tubes 21 to 24 in the refrigerant flow direction when the indoor heat exchangers 5A to 5C serve as condensers. Heat transfer of the refrigerant having a low dryness or a single-phase region (liquid region) is promoted.
1 to 24 (the indoor heat exchangers 5A to 5C)
At the downstream side in the refrigerant flow direction when the evaporator becomes an evaporator), the pressure loss of the refrigerant is smaller than when the heat transfer promoting members S1 to S1 ″ and S2 are inserted.

Thus, the indoor heat exchangers 5A to 5C
The performance of the indoor heat exchangers 5A to 5C can be improved while maintaining a balance between a case in which evaporator becomes an evaporator (during cooling operation) and a case in which it becomes a condenser (during heating operation).

[Fourth Embodiment] Next, FIGS.
5, a fourth embodiment of the present invention will be described. The present embodiment shown in FIGS. 13 to 15 is different from the first and second embodiments in that the indoor heat exchanger 105 is used instead of the indoor heat exchanger 5.
A, 105B, and 105C are used, and other configurations are the same as those of the first and second embodiments shown in FIGS.

As shown schematically in FIGS. 13, 14 and 15, the indoor heat exchangers 105A to 105
C is a heat transfer tube 51-57, 24 through which the refrigerant flows,
Heat transfer tubes 51 to 57 forming the main indoor heat exchanger 8 and heat transfer tubes 24 forming the auxiliary heat exchanger 9 are provided. Then, the heat transfer tubes 51 to 57, 24 are
A flow path (heat transfer tubes 51 to 51) branched into four at the inlet I of the refrigerant
54) merge at the junctions J1 and J2 on the way to form two flow paths (heat transfer tubes 55 and 56), and further merge at the junction J3 to form one flow path (heat transfer tubes 57 and 24). This is a heat transfer tube having a so-called 4-2-1 pass configuration (1-2-4 pass configuration on the basis of the cooling operation) reaching the outlet O.

The heat transfer tubes 51 to 57 and 24 of each pass are, like the heat transfer tubes 21 to 24 shown in FIG. 5, respectively, connected to a plurality of straight tube portions penetrating a large number of plate fins 20a to 20c. It has a plurality of U-shaped connecting pipes (return bends) connecting the ends of the matching straight pipe sections.

Then, as shown in FIGS. 13 and 14,
In the present embodiment, the indoor heat exchangers 105A to 105A
Among the heat transfer tubes 51 to 57, 24 of C, the indoor heat exchanger 10
The heat transfer promoting members S1 to 5A to 105C serve only as condensers only in the downstream portion (the black portion in FIGS. 13 and 14) in the refrigerant flow direction (the direction of the arrow in FIGS. 13 to 15).
S1 ″ and S2 are inserted.

First, the heat exchanger 105 shown in FIG.
In A, the heat transfer promoting members S1 to S1 ″, S2 are not inserted into the heat transfer tubes 51 to 54 on the upstream side, and the junction J
Heat transfer promoting members S1 to S1 ″ and S2 are inserted into heat transfer tubes 55 to 57 and 24 downstream of 1, J2.

Next, the heat exchanger 105 shown in FIG.
In B, the heat transfer tubes 51 to 54 and the heat transfer tubes 55, 5
6, the heat transfer promoting members S1 to S1 ″, S2 are not inserted in the portions that form the second heat exchanger 8a. The second heat exchanger 8a among the heat transfer tubes 55, 56 is formed. Only on the downstream side, and inside the heat transfer tubes 57, 24,
Heat transfer promoting members S1 to S1 ″ and S2 are inserted.

In the heat exchanger 105C shown in FIG. 14, the heat transfer promotion members S1 to S1 ″ and S2 are not inserted into the heat transfer tubes 51 to 56 upstream of the junction J3.
Heat transfer promoting members S1 to S1 ″ and S2 are inserted only into the heat transfer tubes 57 and 24 downstream of the junction J3.

Next, the operation of the present embodiment having such a configuration will be described. According to this embodiment, among the heat transfer tubes 51 to 57, 24, the indoor heat exchangers 105A to 105A
The heat transfer promoting members S1 to S1 ″, S2 promote the heat transfer of the refrigerant having a low dryness or a single-phase region (liquid region) in a downstream portion of the refrigerant flow direction when C is a condenser. Similarly, in the portion of the heat transfer tubes 51 to 57, 24 on the upstream side (downstream in the refrigerant flow direction when the indoor heat exchangers 105A to 105C become evaporators), the heat transfer promoting member S
The pressure loss of the refrigerant is smaller than when 1 to S1 ″ and S2 are inserted.

Thus, the indoor heat exchangers 105A-105A
The performance of the indoor heat exchangers 105A to 105C can be improved while balancing the case where 105C becomes an evaporator (during cooling operation) and the case where 105C becomes a condenser (during heating operation).

In the third and fourth embodiments, the heat transfer tubes 21 to 24 of the indoor heat exchangers 5A to 105C,
Among the 51 to 57, the example in which the heat transfer promoting members S1 to S1 ″ and S2 are attached only to a specific portion on the downstream side when the indoor heat exchangers 5A to 105C serve as condensers has been described. The portions of the heat transfer tubes 21 to 24 and 51 to 57 on which the heat transfer promoting members S1 to S1 ″ and S2 are mounted are not limited to the portions specifically specified in the third and fourth embodiments. That is, the indoor heat exchangers 5A to 105C
In consideration of the balance between the performance during the heating operation in which the condenser serves as a condenser and the performance in the cooling operation also serving as an evaporator, the heat transfer promoting member S
1 to S1 ″, heat transfer tubes 21 to 24 for inserting S2, 51 to 51
The portion 57 may be appropriately adjusted.

[Fifth Embodiment] Next, a fifth embodiment of the present invention will be described with reference to FIG. In the present embodiment shown in FIG. 16, the indoor heat exchanger 5 of the first and second embodiments or the indoor heat exchanger 105A of the fourth embodiment is described.
In the heating operation, only the heat transfer tubes 24 constituting the auxiliary indoor heat exchanger 9 on the downstream side during the heating operation are provided with the heat transfer promoting members S1 to S.
1 ″, S2 is inserted.
This is the same as the first and second embodiments shown in FIGS. 10 to 10 or the fourth embodiment shown in FIGS.

First, the indoor heat exchanger 5 shown in FIG.
D is the indoor heat exchanger 5 of the first embodiment shown in FIG.
, Heat transfer promoting members S1 to S1 ″, S2 are inserted only into the heat transfer tubes 24 that constitute the auxiliary indoor heat exchanger 9. The indoor heat exchanger 105D shown in FIG.
In the indoor heat exchanger 105A of the fourth embodiment shown in FIG. 13A, heat transfer promoting members S1 to S1 ″ and S2 are inserted only into the heat transfer tubes 24 constituting the auxiliary indoor heat exchanger 9. It was done.

As described above, the fin 20c of the auxiliary indoor heat exchanger 9 is connected to the fin 20c of the main indoor heat exchanger 8.
a, 20b, the indoor heat exchanger 5D,
When 105D becomes a condenser (during heating operation),
The auxiliary indoor heat exchanger 9 on the refrigerant outlet O side is a so-called supercooling heat exchanger, and all the refrigerant in the heat transfer tube 24 tends to be in a single-phase region (liquid region).

Next, the operation of the present embodiment having such a configuration will be described. According to the present embodiment, when the indoor heat exchangers 5D and 105D serve as condensers, the single-phase region in the heat transfer tube 24 constituting the auxiliary indoor heat exchanger 9 by the heat transfer promoting members S1 to S1 ″ and S2. This promotes the heat transfer of the refrigerant of the indoor heat exchangers 5D, 10D.
Since the sub-cooling of the refrigerant by the auxiliary indoor heat exchanger 9 when the 5D is a condenser is further promoted, the heating capacity of the air conditioner can be improved.

In the heat transfer tubes 21 to 23 and 51 to 57 constituting the main indoor heat exchanger 8, the heat transfer promoting member S1 is provided.
Since S1 "and S2 are not inserted, the pressure loss of the refrigerant is smaller than when heat transfer promoting members S1 to S1" and S2 are inserted. As a result, it is possible to suppress a decrease in performance when the indoor heat exchangers 5D and 105D serve as evaporators.

In the above embodiment, the indoor heat exchangers 5, 5A to 5D, 105A to 105 of the air conditioner are used.
D (hereinafter simply referred to as “indoor heat exchanger 5 etc.”) has been described, but also in the case of the outdoor heat exchanger 3 shown in FIG. 1, the basic configuration is shown in FIGS. 4 and 5 (or FIGS. 13 to 13). 15)
As in the case of the indoor heat exchanger 5 shown in FIG. In the air conditioner, all or a part of the heat transfer tubes of the outdoor heat exchanger 3 is provided with the heat transfer promoting member S1 similarly to the indoor heat exchanger 5 and the like.
~ S1 "and S2 may be inserted.

Further, only one of the heat transfer tubes such as the outdoor heat exchanger 3 and the indoor heat exchanger 5 is provided with the heat transfer promoting members S1 to S
1 ", S2 may be inserted. In this case, among the outdoor heat exchanger 3 and the indoor heat exchanger 5, etc., the size, the inner / outer volume ratio, the diameter (cross-sectional area) of the heat transfer tube, etc. are taken into consideration. Therefore, it is preferable to insert the heat transfer promoting members S1 to S1 ″ and S2 into the heat transfer tube that needs to promote heat transfer on the refrigerant side of the heat transfer tube.
As a result, the performance of both the indoor heat exchanger 3 and the outdoor heat exchanger 5 can be improved in a well-balanced manner.

Specifically, of the heat transfer tubes of the outdoor heat exchanger 3 and the indoor heat exchanger 5, the heat transfer tube having a larger cross-sectional area (inner diameter) in which the heat transfer coefficient on the refrigerant side of the liquid region is apt to decrease. It is preferable to insert the heat transfer promoting members S1 to S1 ″ and S2 into the outside heat exchanger. Next, of the outdoor heat exchanger 3 and the indoor heat exchanger 5, the supercooling degree (condensation temperature and heat (Difference with the temperature at the outlet of the exchanger) is preferably inserted into the smaller heat transfer tube. It is preferable to insert the heat transfer tube into the larger heat transfer tube.

By the way, in the above embodiment, 5
Since a relatively high-pressure refrigerant having a saturation pressure of 0 ° C. of 2500 kilopascals (kPa) or more is used, the gas side connection pipe C1 and the liquid side shown in FIG. The pipe diameter of the connection pipe C2 can be reduced. Specifically, in an air conditioner having a cooling rated capacity of 3.2 kW or more, one using R22 as a refrigerant usually has an outer diameter of 12.7 mm (1/2 inc.).
h), and the liquid side connection pipe C2 has an outer diameter of 6.4 mm (1/1 /
On the other hand, in an air conditioner having a cooling rating of 3.2 kW or more according to the present invention, the gas-side connection pipe C1 having an outer diameter of 9.5 mm (3/8 inch) is used. Is also good. By reducing the diameter of the gas-side connection pipe C1 or the liquid-side connection pipe C2 in this way, the space occupied by the transfer pipe C shown in FIG. 2 is reduced, and the connection pipes C1, C2 are more flexible. Thus, the workability of the installation around the connecting pipe C of the air conditioner is improved.

[0065]

According to the present invention, the heat transfer on the refrigerant side of the heat transfer tube can be promoted by the heat transfer promoting member inserted into the heat transfer tube. Therefore, the saturation pressure at 50 ° C. is 250
In a heat exchanger of an air conditioner using a refrigerant of 0 kilopascals (kPa) or more, the performance of the heat exchanger can be improved without changing the cross-sectional area of the heat transfer tube or the number of passes.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a refrigeration cycle of an air conditioner to which a heat exchanger according to the present invention is applied.

FIG. 2 is a perspective view showing an external appearance of an air conditioner to which the heat exchanger according to the present invention is applied.

FIG. 3 is a cross-sectional view of the indoor unit shown in FIG.

FIG. 4 is a cross-sectional view of the indoor heat exchanger according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram showing a path configuration of the indoor heat exchanger shown in FIG.

FIG. 6 is a longitudinal sectional view showing the indoor heat exchanger shown in FIG. 4 in a partially enlarged manner.

FIG. 7 is a side view showing a heat transfer promoting member of a first modified example in the first embodiment of the present invention.

FIG. 8 is a perspective view showing a heat transfer promoting member according to a second modification in the first embodiment of the present invention.

FIG. 9 is a cross-sectional view of the indoor heat exchanger according to the second embodiment of the present invention.

FIG. 10 is a view showing another example of the cross-sectional shape of the heat transfer promoting member shown in FIG. 9;

FIG. 11 is a cross-sectional view of an indoor heat exchanger according to a third embodiment of the present invention.

FIG. 12 is a cross-sectional view of another indoor heat exchanger according to the third embodiment of the present invention.

FIG. 13 is a cross-sectional view of an indoor heat exchanger according to a fourth embodiment of the present invention.

FIG. 14 is a cross-sectional view of another indoor heat exchanger according to the fourth embodiment of the present invention.

FIG. 15 is a schematic diagram showing a path configuration of the indoor heat exchanger shown in FIGS. 13 and 14.

FIG. 16 is a cross-sectional view of an indoor heat exchanger according to a fifth embodiment of the present invention.

FIG. 17 is a cross-sectional view showing an example of an indoor heat exchanger of a conventional air conditioner.

FIG. 18 is a schematic diagram showing a path configuration of the indoor heat exchanger shown in FIG.

[Explanation of symbols]

3 Outdoor heat exchanger 5, 5A-5D, 105A-105D, 5 'Indoor heat exchanger 8 Main indoor heat exchanger 8a First heat exchanger 8b Second heat exchanger 9 Auxiliary heat exchangers 21-24, 51-51 57 Heat transfer tube 31-34 Straight tube portion 41-44 U-shaped connecting tube (return vent) A outdoor unit B indoor unit J, J1-J3 junction S1, S1 ', S1 "Heat transfer promoting member in twisted tape shape S2 Coil spring shaped heat transfer promoting member

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Shigenori Hori 3-3-9, Shimbashi, Minato-ku, Tokyo Inside Toshiba AV EE Co., Ltd.

Claims (6)

[Claims] In a heat exchanger of an air conditioner having a heat transfer tube through which a refrigerant flows, a refrigerant having a saturation pressure of 50 ° C. and a pressure of 2500 kilopascals (kPa) or more is used as the refrigerant. A heat exchanger for an air conditioner, wherein a heat transfer promoting member for changing a flow state of the refrigerant to promote heat transfer is inserted. 2. The heat exchanger according to claim 1, wherein the heat transfer promoting member has a twisted tape shape. 3. The heat exchanger according to claim 1, wherein the heat transfer promoting member has a coil spring shape. 4. The heat transfer promoting member is inserted only into a portion of the heat transfer tube on the downstream side in the refrigerant flow direction when the heat exchanger is a condenser. 4. The heat exchanger for an air conditioner according to any one of 3. 5. The heat transfer tube has a multi-pass configuration having one or more junctions when the heat exchanger is a condenser, wherein the heat exchanger is a condenser and a heat exchanger. The air according to any one of claims 1 to 3, wherein the heat transfer promoting member is inserted only in a portion downstream of all or a part of the merging portion in a refrigerant flow direction. A heat exchanger for a harmony device. 6. The heat exchanger according to claim 1, further comprising an indoor heat exchanger and an outdoor heat exchanger, wherein one of the indoor heat exchanger and the outdoor heat exchanger is the heat exchanger according to claim 1. An air conditioner, comprising: