TWI551837B - Air conditioner - Google Patents

Description

Air conditioner

The present invention relates to air having a multipath heat exchanger Adjust the machine.

As the diameter of the refrigerant passage of the heat exchanger is reduced, the flow loss on the refrigerant side is increased. Therefore, in the related art, the refrigerant passage is multipathed, thereby reducing the loss. Further, in the heat exchanger functioning as an evaporator, even in the case of multipathization, if the refrigerant distribution in the gas-liquid two-phase state is not appropriate, there is a problem that the performance of the air conditioner is lowered. As a technique for solving such a problem, Patent Document 1 proposes a technique in which a refrigerant pipe (refrigerant passage) that is divided into a plurality of paths is used, and a refrigerant flowing through each refrigerant pipe is once once merged, and then a shunt tube is provided. It is diverted.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. Hei 8-313115

However, in the technique described in Patent Document 1, the path is divided into the front and rear (upstream side and downstream side) with respect to the air flow direction. Therefore, the path on the front side (upstream side in the air flow direction) is warm air circulation, and is located behind. The path on the side (the downstream side in the air flow direction) is the air that is cooled by the front side, and the heat exchange cannot be performed efficiently.

In view of this, the refrigerant passage of the heat exchanger is divided into the upper and lower sides with respect to the air flow direction, and the distribution pipe (shunt pipe) is provided in the refrigerant pipe separated upward and downward, but in this case, since the distribution pipe is not horizontal Therefore, the refrigerant cannot be uniformly distributed due to the influence of gravity, and the heat exchange performance as the evaporator cannot be improved, causing problems.

The present invention has been developed in order to solve the above-mentioned conventional problems, and an object thereof is to provide an evaporator with a high-performance air conditioner by utilizing the original heat exchange capability.

According to a first aspect of the invention, a compressor includes: a compressor that compresses a refrigerant; a condenser that condenses a refrigerant compressed by the compressor; and a pressure reducing device that decompresses a refrigerant condensed in the condenser; and an evaporator Cooling the refrigerant in the decompressing device; the evaporator having: a plurality of refrigerant passages, at least a portion of which is vertically divided vertically; and a distributor for diverting the refrigerant at one of both ends of the plurality of refrigerant passages To the aforementioned plurality of refrigerant passages; the manifold, in the foregoing plural The other of the two ends of the refrigerant passages merges the refrigerant flowing through the plurality of refrigerant passages; and the communication passage connects the plurality of refrigerant passages; the refrigerant passage has a heat conduction passage that extends in the horizontal direction and performs heat. And the curved passage is separated from the heat transfer passage and returned to the other heat conduction passage; and the communication passage communicates with the outer peripheral side surface of the curved passage in the middle of the refrigerant passage.

A second invention characterized in that it comprises at least a compressor, a refrigerant, a condenser that condenses the refrigerant compressed by the compressor, a pressure reducing device that decompresses the refrigerant condensed in the condenser, and an evaporator that evaporates the refrigerant under reduced pressure of the pressure reducing device; The evaporator has: a plurality of refrigerant passages, at least a portion of which is vertically divided vertically; the distributor, one of the two ends of the plurality of refrigerant passages, diverts the refrigerant to the plurality of refrigerant passages; and the combiner, in the plurality of The other of the two ends of the refrigerant passage merges the refrigerant flowing through the plurality of refrigerant passages; and the communication passage connects the plurality of refrigerant passages; the refrigerant passage has a heat conduction passage that extends in the horizontal direction and performs heat exchange And the curved passage is separated from the heat conduction passage and returned to the other heat conduction passage; and the communication passage communicates with the surface on the outer circumferential side after the flow of the refrigerant in the middle of the refrigerant passage.

A third invention, comprising: at least: a compressor, a refrigerant, a condenser that condenses the refrigerant compressed by the compressor, a pressure reducing device that decompresses the refrigerant condensed in the condenser, and an evaporator that evaporates the refrigerant under reduced pressure of the pressure reducing device; The evaporator has: a plurality of refrigerant passages, at least a part of which is vertically divided And a distributor that diverts the refrigerant to the plurality of refrigerant passages at one of both ends of the plurality of refrigerant passages; and the other of the two ends of the plurality of refrigerant passages at the other of the plurality of refrigerant passages a refrigerant flow flowing through the refrigerant passage; and a communication passage connecting the plurality of refrigerant passages; the refrigerant passage having a heat conduction passage extending in a horizontal direction and performing heat exchange; and a curved passage exiting from the heat conduction passage to return to the other The heat conduction passage; the communication passage is in communication with a bottom surface of the outlet side of the heat conduction passage in the middle of the refrigerant passage.

According to the present invention, the evaporator can be made to have the original heat exchange capability, and a high-performance air conditioner can be provided.

1‧‧‧Air conditioner

2‧‧‧Compressor

3‧‧‧ indoor heat exchanger

4‧‧‧Reducing device

5‧‧‧Outdoor heat exchanger

6‧‧‧ four-way valve

30, 31, 40, 41, 51, 53, 61, 63, 71, 73, 81, 83‧‧‧ refrigerant passage

100‧‧‧Fins

110‧‧‧U-shaped heat pipe (thermal path)

111a, 142a, 143a‧‧‧bend tube (bending path)

111b, 111d, 142b, 143b‧‧‧ outer peripheral surface (outer side)

110e‧‧‧ bottom

111, 111A, 111B, 111C, 111D, 111E, 111F, 111M, 111N, 111O, 111P, 111Q, 111R, 142, 143‧‧‧

11, 933, 951, 953, 973 ‧ ‧ distributor

12, 934, 952, 954, 974 ‧ ‧ confluence

990, 991, 992, 993, 996, 997, 998, 999‧‧‧Connected pipes (connected roads)

[Fig. 1] An air conditioner is shown as a whole.

Fig. 2 is a schematic exploded perspective view of a heat exchanger of an air conditioner.

Fig. 3 is a schematic perspective view of a heat exchanger according to a first embodiment.

Fig. 4 is a view showing a change in temperature of the refrigerant in the evaporator, (a) is a schematic diagram of temperature changes at the time of equal distribution, and (b) is a schematic diagram showing temperature changes at the time of uneven distribution.

[Fig. 5] discloses a change in the pressure of the refrigerant in the evaporator, (a) a change in pressure at the time of equal distribution, and (b) a change in pressure at the time of uneven distribution. Schematic table.

Fig. 6 shows a first installation mode of the communication path, wherein (a) is a plan view and (b) is a cross-sectional view taken along line A-A.

Fig. 7 is a view showing a second installation mode of the communication path, wherein (a) is a plan view and (b) is a cross-sectional view taken along line B-B.

Fig. 8 is a view showing a third arrangement of the communication path, wherein (a) is a plan view and (b) is a C-C line sectional view.

Fig. 9 is a schematic cross-sectional view showing a fourth arrangement of the communication path.

Fig. 10 discloses a gas-liquid two-phase flow, in which (a) is a separation flow and (b) is an annular flow.

Fig. 11 is a schematic side view showing the heat exchanger of the second embodiment.

Fig. 12 is a schematic side view showing a heat exchanger according to a third embodiment.

Fig. 13 is a schematic side view showing the heat exchanger of the fourth embodiment.

Hereinafter, embodiments of the present invention will be specifically described using the drawings. First, the overall configuration of the air conditioner 1 will be described with reference to Fig. 1 . In the first embodiment shown in Fig. 3, a heat exchanger which is simplified in the first embodiment and a second embodiment shown in Fig. 11 are an outdoor heat exchanger for a household air conditioner, as shown in Fig. 12. In the third embodiment and the fourth embodiment shown in Fig. 13, an indoor heat exchanger for a home air conditioner will be described. In addition, it is not limited to household use, and can also be applied to a business air conditioner.

As shown in Figure 1, the air conditioner 1, mainly by the compressor 2. The indoor heat exchanger 3, the decompression device 4 (expansion valve, etc.), the outdoor heat exchanger 5, the four-way valve 6, and the like. These elemental devices are sequentially connected by the refrigerant pipes 120, 121, 122, 123, 124, and 125. Further, although not shown, for example, a cross-flow fan is provided in the indoor heat exchanger 3, and a propeller fan is provided in the outdoor heat exchanger 5.

During the cooling operation, the outdoor heat exchanger 5 functions as a condenser. The indoor heat exchanger 3 functions as an evaporator. In this case, the refrigerant is in accordance with the compressor, the refrigerant pipe 120, the four-way valve 6, the refrigerant pipe 121, the outdoor heat exchanger 5, the refrigerant pipe 122, the decompression device 4, the refrigerant pipe 123, and the indoor heat exchange. The refrigerant 3, the refrigerant pipe 124, the four-way valve 6, the refrigerant pipe 125, and the compressor 2 are circulated in the air conditioner 1 while changing the state of the compressor.

Specifically, compressed by the compressor 2, at high pressure and high temperature The refrigerant that has been discharged in the vapor state flows into the outdoor heat exchanger 5, and heat is released therein to change into a high-pressure medium-temperature liquid refrigerant. The liquid refrigerant passes through the decompressing device 4, and becomes a gas-liquid two-phase state (gas-liquid two-phase flow) having a low pressure and a low temperature, and is then taken away by the surrounding (indoor air) in the indoor heat exchanger 3 to become a low-pressure low-temperature vapor state. (gas state), and then sucked into the compressor 2 again, thus repeating the cycle.

On the other hand, if the flow of the refrigerant is switched by the four-way valve 6 In the direction, it becomes a heating operation. In this case, the outdoor heat exchanger 5 functions as a condenser when the evaporator and the indoor heat exchanger 3 are used. At this time, the refrigerant is in accordance with the compressor 2, the refrigerant pipe 120, the four-way valve 6, the refrigerant pipe 124, the indoor heat exchanger 3, the refrigerant pipe 123, as indicated by a broken line arrow, The order of the decompression device 4, the refrigerant pipe 122, the outdoor heat exchanger 5, the refrigerant pipe 121, the four-way valve 6, the refrigerant pipe 125, and the compressor 2 circulates in the air conditioner 1.

Figure 2 is a schematic exploded view of the heat exchanger of the air conditioner Stereo picture.

As shown in FIG. 2, the heat exchanger used as the indoor heat exchanger 3 or the outdoor heat exchanger 5 is, for example, a cross-fin tube type heat exchanger configured to have a plurality of aluminum sheets. The fins 100 are formed by a U-shaped heat transfer pipe 110 (heat transfer path, hereinafter abbreviated as heat transfer pipe 110) which is bent into a U shape. The fins 100 and the heat transfer tubes 110 are brought into close contact with each other by hydraulically or mechanically expanding the heat transfer tubes 110 inserted into the fins 100. In addition, the heat pipe 110 is configured to extend through the fins 100 extending in a nearly horizontal direction (a direction orthogonal to the vertical direction).

In addition, at the end of the heat pipe 110, by welding, etc. A return bend 111 for connecting to the ends of the other heat transfer tubes 110 is joined to constitute a refrigerant passage. In this way, the heat exchanger has a path in which the one side of the fin 100 is meandered and folded at one end in the stacking direction of the fins 100. Further, the return bend 111 is not limited to the U shape as will be described later.

In addition, the fin 100 is connected to the heat pipe 110 at the fin 100. The portion of the air flowing between the fins 100 corresponds to the heat exchange region of the heat exchanger. Further, the U-shaped tube portion of the heat transfer tube 110 on the one end side in the stacking direction of the fin 100 and the portion of the return bend tube 111 on the other end side are regions which do not contribute to heat exchange.

(First embodiment)

Fig. 3 is a schematic perspective view of the heat exchanger according to the first embodiment. In addition, the arrow (solid line) in the figure indicates the flow direction of the refrigerant when the heat exchanger functions as an evaporator. For example, the heat exchanger shown in Fig. 3 is the outdoor heat exchanger 5, in the case of heating operation.

As shown in Fig. 3, the heat exchanger of the first embodiment is The refrigerant passages 30 and 40 divided into two paths, the distributor 11, the manifold 12, and the communication pipe 990 (communication path) are included.

The refrigerant passage 30 is disposed perpendicular to the heat exchanger The upper portion of the center portion (in the vertical direction) (see an arrow pointing upward with respect to the single-point chain line); the refrigerant passage 40 is disposed at the lower side of the center portion in the vertical direction (vertical direction) of the heat exchanger. Area (refer to the arrow pointing downward with respect to the single point chain). In this manner, the refrigerant passage 30 and the refrigerant passage 40 are not disposed in the vertical direction orthogonal to the air flow direction, but are disposed in the vertical direction orthogonal to the air flow direction.

The distributor 11 is connected to both ends of the refrigerant passages 30, 40. One of the two inlets (the inlets 110a and 110b) is decompressed by the decompressing device 4 (see FIG. 1), and the refrigerant in the gas-liquid two-phase state is branched (distributed) to the refrigerant passage 30 and the refrigerant passage 40.

The manifold 12 is connected to both ends of the refrigerant passages 30 and 40. The other of the two sides (outlet 110c, 110d) is connected in a binary shape and will be in a vapor state.

The communication pipe 990 is a return pipe on the way of the refrigerant passage 30 111A (111) is connected to the return pipe 111B (111) in the middle of the refrigerant passage 40, and constitutes a passage that connects the refrigerant passage 30 and the refrigerant passage 40. In addition, the arrow indicated by the communication pipe 990 indicates the direction in which the refrigerant flows when the pressure of the refrigerant passage 40 is higher than the pressure of the refrigerant passage 30 at the time of uneven distribution described later. The detailed configuration of the communication pipe 990 will be described later.

In the refrigerant passage 30 shown in Fig. 3, for example, the refrigerant is from the inlet. The port 110a flows in a direction perpendicular to the vertical direction on the side of the front side (upstream side) with respect to the air flow direction (see the arrow in the drawing), and then is located on the rear side with respect to the air flow direction at the uppermost portion of the heat exchanger ( The passage on the downstream side flows sideways downward in the vertical direction, and exits the outlet 110c to reach the header 12.

Moreover, in the refrigerant passage 40 shown in FIG. 3, for example, the refrigerant is From the inlet 110b, the passage on the front side (upstream side) with respect to the air flow direction flows sideways downward in the vertical direction, and then in the lowermost portion of the heat exchanger, on the rear side (downstream side) with respect to the air flow direction. One side of the snake flows upward in the vertical direction, and exits the outlet 110d to reach the combiner 12, and merges with the refrigerant passage 30.

In the heat exchanger according to the first embodiment configured as above, The refrigerant toward the refrigerant passage 30 passes through the upper portion of the heat exchanger (evaporator), and the refrigerant toward the refrigerant passage 40 passes through the lower portion of the heat exchanger (evaporator) and then with the air sent by a fan (not shown). Do heat exchange and evaporate the refrigerant. Then, the refrigerant flows into the combiner 12 and flows to the compressor 2.

Figure 4 is a diagram showing the change in the temperature of the refrigerant in the evaporator, (a) A schematic diagram of temperature changes at the time of equal distribution, and (b) a schematic diagram of temperature changes at the time of uneven distribution. In addition, the broken line in FIG. 4(b) indicates the temperature change of the refrigerant passing through the refrigerant passage 30, and the solid line indicates the temperature change of the refrigerant passing through the refrigerant passage 40. 4(a) shows a case where the temperature change of the refrigerant passage 30 coincides with the temperature change of the refrigerant passage 40.

In addition, the "distance from the entrance" is shown on the horizontal axis in Fig. 4, It means the distance (length) when the inlets 110a and 110b are used as a reference. In addition, the "full length of each path" means the total length of the tubes of the respective refrigerant passages 30, 40, and includes the heat transfer pipe 110 (refer to FIG. 3) and the return bend pipe 111 from the inlets 110a and 110b to the outlets 110c and 110d (refer to the figure). 3) The length. Therefore, if the value (percentage) of the horizontal axis (the distance from the entrance/the total length of each path) is low, it is close to the inlets 110a, 110b; as the value (percentage) becomes higher, it gradually moves away from the inlets 110a, 110b (gradually approaching) Exits 110c, 110d).

In addition, the "entry" is not limited to the one shown in Figure 3. The inlets 110a, 110b may also be the branch points P of the dispenser 11 (see Fig. 3). Further, regarding the "full length of each path", the U-shaped portion of the heat transfer pipe 110 and the portion of the return pipe 111 protruding from the end portion in the stacking direction of the fin 100 to the outer side are not helpful for heat exchange. In part, it is also possible to remove the parts of these parts as "the full length of each path".

Having said that, as shown in Figure 4(a), when the refrigerant is being distributed The device 11 is equally divided (the liquid refrigerant flow rate and the gas refrigerant flow rate toward the respective refrigerant passages 30 and 40 are the same), and the refrigerant passage 30 is cold. The medium temperature and the temperature of the refrigerant in the refrigerant passage 40 almost change in the same manner, and the original heat exchange capacity of the evaporator can be exhibited.

However, due to the shape of the piping fitted on the upstream side of the distributor 11, Other factors, gas-liquid two-phase flow of gas refrigerant and liquid refrigerant may be biased. Further, the shape of the pipe attached to the upstream side of the distributor 11 is generally narrow in the upstream side of the distributor 11, and the straight pipe is rarely assembled with respect to the inlets 110a and 110b (refer to Fig. 3), so that the L-shaped word is assembled. In the case of a pipe that is bent like a shape, that is, a centrifugal force occurs with respect to the refrigerant.

For example, if the amount of liquid refrigerant flowing to the refrigerant passage 40 More than the refrigerant passage 30, when uneven refrigerant distribution occurs as described above, as shown in FIG. 4(b), the refrigerant temperature in the refrigerant passage 40 is lowered toward the outlet 110d (see FIG. 3). On the other hand, in the refrigerant passage 30, the liquid refrigerant becomes a gas refrigerant as the liquid refrigerant evaporates in the middle of the refrigerant passage 30, and the refrigerant temperature rises to the vicinity of the air temperature (not shown), and the passage thereafter (near the outlet 110c of the refrigerant passage 30) In the passage), efficient heat exchange is not possible. As a result, the performance as an air conditioner is lowered.

In view of this, in order to prevent unequalities as shown in FIG. 4(b) In the first embodiment, the communication pipe 990 (communication path) is provided, for example, in the middle of the return pipe 111A (111) and the refrigerant passage 40 in the middle of the refrigerant passage 30. The elbow 111B (111) is connected to communicate the refrigerant passage 30 and the refrigerant passage 40.

Figure 5 is a diagram showing the change in refrigerant pressure in the evaporator, (a) The pressure change at the time of equal distribution and (b) the pressure change diagram when the distribution is uneven. In addition, the broken line in FIG. 5(b) indicates the pressure change of the refrigerant passing through the refrigerant passage 30, and the solid line indicates the pressure change of the refrigerant passing through the refrigerant passage 40. Fig. 5(a) shows a case where the pressure change of the refrigerant passage 30 coincides with the pressure change of the refrigerant passage 40.

As shown in Figure 5(a), when the gas-liquid two-phase flow is equal to the refrigerant In the case of the ground distribution, the pressure change of the refrigerant in the refrigerant passage 30 and the refrigerant passage 40 is the same. On the other hand, when uneven refrigerant distribution occurs, the flow rate of the liquid refrigerant flowing through the refrigerant passage 40 and the refrigerant passage 30 flowing in the refrigerant passage 30 is smaller, so the evaporation progresses faster and the dryness increases. Also fast. Therefore, in the refrigerant passage 30, as shown in Fig. 5(b), the refrigerant pressure starts to decrease at a relatively fast pace, but exceeds a certain position (the distance from the inlet/the total length of each path) and the pressure of the refrigerant. The descending speed becomes slower than the pressure drop rate of the refrigerant passage 40, and the refrigerant pressures of the refrigerant passages 30, 40 become the same at the outlets 110c, 110d. That is, the pressure changes of the refrigerant in the refrigerant passages 30 and 40 are different, and there is a pressure difference between the refrigerant passage 30 and the refrigerant passage 40 in the middle of the refrigerant passages 30 and 40.

In the present embodiment, the refrigerant passage is configured to The pressure difference between the refrigerant passage 40 and the refrigerant passage 40 causes the liquid refrigerant to move, thereby improving the heat exchange performance of the evaporator.

As shown in FIG. 5(b), when flowing in each of the refrigerant passages 30, 40 In the case where the flow rates of the liquid refrigerant and the gas refrigerant are different, the refrigerant passage On the way of 30 and 40, there is a pressure difference between the refrigerant passage 30 and the refrigerant passage 40. Accordingly, by providing the communication pipe 990 (see FIG. 3), the refrigerant moves from the refrigerant passage 40 having a high pressure to the refrigerant passage 30 having a low pressure (see an arrow in FIG. 3) through the communication pipe 990 in response to the pressure difference.

When the refrigerant passing through the communication pipe 990 is a liquid refrigerant Then, the evaporation progresses rapidly, and the liquid refrigerant is supplied to the refrigerant passage 30 whose refrigerant dryness is higher than the refrigerant passage 40 (that is, the liquid refrigerant ratio is small). Therefore, compared with the case where the communication pipe 990 is not provided, the end of evaporation becomes slow (refer to FIG. 4(b)), so that the heat transfer area of the heat exchanger can be effectively utilized. Further, in the refrigerant passage 40, the liquid refrigerant is reduced, so that it is possible to solve the problem that the liquid refrigerant evaporation has not returned to the compressor.

However, when the refrigerant passing through the communication pipe 990 is a gas Then, the gas refrigerant is supplied to the refrigerant passage 30 having a higher dryness of the refrigerant than the refrigerant passage 40, and the degree of dryness is further increased. Accordingly, the evaporation is terminated earlier than the case where the communication pipe 990 is not provided, resulting in ineffective use. The heat transfer area increases. On the other hand, in the refrigerant passage 40, as the gas refrigerant is reduced, the thermal conductivity is lost, and the evaporation progress is slower than the case where the communication pipe 990 is not provided. As a result, the performance of the heat exchanger will be degraded.

In view of this, a means is needed to prevent gas in the connecting tube 990. The body refrigerant moves only the liquid refrigerant. This means will be described with reference to Figs. 6 to 10 . 6 is a schematic cross-sectional view showing a first installation mode of a communication path, FIG. 7 is a schematic cross-sectional view showing a second installation mode of the communication path, FIG. 8 is a schematic cross-sectional view showing a third installation mode of the communication path, and FIG. 9 is a fourth sectional view of the communication path. Set side Fig. 10 shows a gas-liquid two-phase flow, (a) is a separation flow, and (b) is an annular flow.

The first setting mode shown in FIG. 6 is to connect the communication tube 990. One end is connected to the outer peripheral surface 111b of the curved tube 111a (the curved passage, the range surrounded by the single-point chain line) which is bent into a semicircular shape among the return bends 111A (111) and 111B (111) (the outer peripheral side surface, curved The outer side)).

As such, when the gas-liquid two-phase flow passes through the curved tube 111a, Due to the centrifugal force, the liquid refrigerant having a high density moves on the inner wall surface on the outer peripheral surface 111b side of the curved tube 111a. On the other hand, the gas refrigerant moves on the inner wall surface on the inner peripheral surface 111c side of the curved tube 111a. Therefore, when the refrigerant pressure of the refrigerant passage 30 is lower than the refrigerant pressure of the refrigerant passage 40 (see FIG. 5(b)), the communication pipe 990 connected to the outer peripheral surface 111b of the curved pipe 111a of the return pipe 111B will be connected. The liquid refrigerant flows and flows into the refrigerant passage 40 on the side of the return pipe 111A.

Like this, it is not just a connection of the connecting pipe 990 to the back. The elbows 111A, 111B are connected to the outer peripheral surface 111b of the curved tube 111a of the return bends 111A, 111B, whereby the refrigerant that moves through the communication tube 990 is prevented from being in the gas phase due to the centrifugal force. The liquid refrigerant flows through.

In this way, the liquid refrigerant will pass from the low-drying refrigerant. The path 40 flows to the refrigerant passage 30 having a high degree of dryness. Therefore, the liquid refrigerant is supplied to the refrigerant passage 30 having a high degree of dryness, and at the same time, the liquid refrigerant in the refrigerant passage 40 having a low dryness is reduced. That is, the communication tube 990 is lowered. In the refrigerant passage, the difference in the state of the refrigerant is reduced, and the difference in the degree of progress of the evaporation of the refrigerant existing between the refrigerant passage 30 and the refrigerant passage 40 is also small.

In addition, when the refrigerant of the gas-liquid two-phase flow is equally distributed Next, as shown in FIG. 5(a), since there is no pressure difference between the refrigerant passage 30 and the refrigerant passage 40, the refrigerant movement does not occur even if the communication pipe 990 is provided. That is to say, the performance of the heat exchanger is not impaired by the arrangement of the communication pipe 990.

In Fig. 6, it is illustrated at one end of the curved tube 111a and another In the case where the communication tube 990 is connected to the intermediate position of one end, the liquid refrigerant can be moved to the inner wall surface on the outer peripheral surface 111b side of the curved tube 111a by centrifugal force, and is not limited to the intermediate position. In the case of the first installation mode, when the refrigerant is introduced from one of the return pipes 111A and 111B as shown by the broken line in FIG. 6, it is also shown by the solid line in FIG. When the other of the 111A and 111B is introduced into the refrigerant, both of them can be applied.

As described above, in the first embodiment, even if it is a complex The heat exchangers in which the plurality of refrigerant passages 30 and 40 are vertically separated in the vertical direction are connected to the outer peripheral surface 111b of the curved tube 111a by connecting the communication tube 990 in the middle of the refrigerant passages 30 and 40, and then When the liquid refrigerant moves, the difference in the degree of progress of the evaporation of the refrigerant existing between the refrigerant passages can be reduced in the refrigerant passage which is lowered by the communication pipe 990, and the heat exchange performance as the evaporator and the machine performance of the air conditioner 1 can be improved. Furthermore, since the structure of the communication pipe 990 is extremely simple, it can be manufactured at a relatively low cost.

Further, in the first embodiment, it is preferable that the communication tube 990 It is designed to be slightly the same distance from the distributor 11 in the refrigerant passages 30, 40 (for example, in the refrigerant passages 30, 40, the refrigerant is on the outlet side of the second heat transfer pipe 110).

When the refrigerant distribution is uneven (see FIG. 5(b)), for example, the outlet of the second heat transfer pipe 110 of the refrigerant passage 30 and the outlet of the third heat transfer pipe 110 of the refrigerant passage 40 are connected by the communication pipe 990. Then, the lengths of the refrigerant passage 30 and the refrigerant passage 40 upstream of the communication pipe are different. In this case, since there is almost no pressure difference between the refrigerant passage 30 and the refrigerant passage 40, the refrigerant movement does not occur, and the effect of providing the communication pipe 990 is completely lost. Alternatively, since the refrigerant passage 40 has a lower pressure than the refrigerant passage 30, the liquid refrigerant moves from the refrigerant passage 30 to the refrigerant passage 40. As a result, in the refrigerant passage 30 in which the communication pipe 990 is lowered, the liquid refrigerant is less than the case where the communication pipe 990 is not provided, and the superheated state is earlier. On the other hand, in the refrigerant passage 40 in which the communication pipe 990 is lowered, the liquid refrigerant is more than the case where the communication pipe 990 is not provided, so that the refrigerant evaporation cannot be completed.

For example, the outlet of the third heat transfer pipe 110 of the refrigerant passage 30 and the outlet of the second heat transfer pipe 110 of the refrigerant passage 40 are connected by the communication pipe 990, and the length of the refrigerant passage 30 and the refrigerant passage 40 upstream of the communication pipe. It will be different. In this case, since the pressure difference existing between the refrigerant passage 30 and the refrigerant passage 40 is large, a large amount of liquid refrigerant flows from the refrigerant passage 40 to the refrigerant passage 30. However, in the refrigerant passage 30, there are only two heat transfer pipes downstream of the communication pipe 990, so that the refrigerant cannot be evaporated. On the other hand, in the refrigerant passage 40, the refrigerant passes through the three heat pipes downstream of the communication pipe 990, and there is a possibility that the refrigerant becomes an overheated state early. As a result, the performance of the heat exchanger cannot be improved.

Further, when the refrigerant distribution is uniform (see Fig. 5 (a)), if the liquid refrigerant moves between the refrigerant passages, the refrigerant evaporation cannot be completed in the refrigerant passage in which the liquid refrigerant increases; on the other hand, the liquid refrigerant is reduced. In the refrigerant passage, the evaporation of the refrigerant will end early. Therefore, it will damage the performance of the heat exchanger.

As described above, in any of the foregoing cases, if the communication pipe is provided at a position different from the heat exchanger inlet, the performance of the heat exchanger cannot be improved. Accordingly, as in the first embodiment, the communication tube 990 is designed to be slightly the same distance from the distributor 11 of the refrigerant passages 30, 40, whereby the heat transfer area of the heat exchanger can be effectively utilized, and the heat exchanger can be improved. performance.

Further, in the first embodiment, it is preferable that the communication pipe 990 is provided in a place where the pressure difference between the refrigerant passage 30 and the refrigerant passage 40 is increased, for example, the range Q shown in Fig. 5(b). Incidentally, even if the communication pipe is provided at a position where the pressure difference is very small, the pressure of each of the refrigerant passages 30, 40 hardly changes, and the effect of providing the communication pipe may be completely lost.

In addition, the arrangement of the communication pipe 990 is not limited to that shown in FIG. 6. For example, as shown in FIG. 7, as the second installation mode, the communication pipe 991 is connected to the outer circumferential surface 111d immediately after the refrigerant downstream side of the bending pipe 111a (bending path) among the return pipes 111A and 111B. Even with this arrangement, the liquid refrigerant can still be used due to the centrifugal force. The outer peripheral surface 111d immediately after the bending of the curved tube 111a is moved while being moved to the outer peripheral surface 111b side of the curved tube 111a, and only the liquid refrigerant flows into the communicating tube 991.

In addition, as shown in FIG. 8, as the third setting party In the refrigerant pipes 142 and 143 having an L-shaped cross section, as in the second installation mode, the refrigerant pipes 142 and 143 are adjacent to the curved pipes 142a and 143a (the curved passage, the range surrounded by the single-point chain line). The outer peripheral surfaces 142b and 143b after the downstream side of the refrigerant are connected to the communication pipe 991 (see the communication pipe 991 of Fig. 11 to be described later). Even in such a manner, the liquid refrigerant flows into the communication pipe 991 by the action of the centrifugal force.

In addition, as shown in FIG. 9, in the heat exchanger The fin 100 and the bottom surface 110e of the heat transfer pipe 110 protruding from the heat exchange region are connected to the communication pipe 991. In such a heat exchanger, since the heat transfer pipe 110 is disposed almost horizontally, the flow state in the heat transfer pipe 110 is as shown in FIG. 10(a) due to the influence of gravity, and the liquid refrigerant flows at the bottom of the heat transfer pipe 110. The gas refrigerant flows on the upper side of the heat transfer pipe 110, that is, a so-called separation flow; or as shown in FIG. 10(b), the liquid refrigerant flows on the inner wall surface of the heat transfer pipe 110, and the gas refrigerant is at the center of the circumscribed section of the heat transfer pipe 110. The flow, that is, the so-called annular flow; in either case, only the liquid refrigerant flows into the communication pipe 991 connected to the bottom surface 110e (pipe wall surface) of the heat transfer pipe 110.

In the first embodiment, the communication tube 990 is used. The case of connecting to the return bend pipes 111A, 111B is taken as an example, but the communication pipe 990 may be connected to the heat exchange area via the heat exchanger and the return bend pipe. The U-shaped tube portion 110s of the heat transfer tube 110 on the opposite side of the 111A and 111B (see Fig. 2).

In addition, the communication tube 990 is not limited to being welded by The return bend pipes 111A and 111B, the refrigerant pipes 142 and 143, and the heat transfer pipe 110 are joined, and an integrally formed one can also be used.

Further, in the first embodiment, the communication pipe 990 is used. The case where it is provided only in one place is described as an example, but it is not limited to one place, and may be provided in two or more places as will be described later. As a result, the difference in the state of the refrigerant between the refrigerant passages 30 and 40 can be further reduced.

(Second embodiment)

Fig. 11 is a schematic side view showing the heat exchanger of the second embodiment. 11 shows an example of a household outdoor heat exchanger, in which a broken line in FIG. 11 indicates a U-shaped pipe portion of a heat pipe (corresponding to the heat pipe 110 of FIG. 2), and a thick arrow indicates when the heat exchanger functions as an evaporator. The flow direction of the refrigerant (when the heating operation is performed, that is, when the outdoor heat exchanger 5 functions as an evaporator, and when the indoor heat exchanger 3 functions as a condenser, the flow direction of the refrigerant). Further, the piping shown by the thick solid line indicates the communication pipes 991, 992, and 993 corresponding to the communication paths in the patent application.

As shown in Fig. 11, in the heat exchanger (evaporator) of the second embodiment, the pressure reducing device 4 (see Fig. 1) and the distributor 933 are connected via a refrigerant pipe 122, and are divided into two refrigerant passages in the distributor 933. 31 and the refrigerant passage 41.

One of the refrigerant passages 31 is through the distributor 933 and The refrigerant pipe 140 to which the heat transfer pipe opening end 301 (one end) of the heat transfer pipe 351 is connected is passed through the heat pipe 351, 352 at the lower portion of the heat exchanger, and is passed through the refrigerant pipe 142 connected to the heat pipe open end 304 of the heat pipe 352. The distributor 953 is divided into two refrigerant passages 51 and a refrigerant passage 61 at the distributor 953. Further, the refrigerant passage 51 and the refrigerant passage 61 are vertically divided in the vertical direction.

The refrigerant passage 51 is a refrigerant pipe 144 that connects the distributor 953 and the heat pipe opening 501 of the heat transfer pipe 551, and then reaches the heat pipe 551, 552, 553, 554, 555, 556 at the uppermost portion of the heat exchanger. Cone 954 (the other end).

The refrigerant passage 61 is a refrigerant pipe 145 that connects the distributor 953 and the heat pipe opening 601 of the heat transfer pipe 651, and then passes through the heat pipes 651, 652, 653, 654, 655, and 656 at the upper portion of the heat exchanger. The device 954 is connected to the refrigerant passage 51.

The other refrigerant passage 41 is a refrigerant pipe 141 that connects the distributor 933 and the heat transfer pipe opening end 401 (one end) of the heat transfer pipe 451, and then passes through the heat pipe 451, 452 at the lower portion of the heat exchanger, and transmits the heat pipe. The refrigerant pipe 143 connected to the open end 404 of the heat pipe 452 reaches the distributor 973, and is divided into two refrigerant passages 71 and a refrigerant passage 81 at the distributor 973. The refrigerant passage 71 and the refrigerant passage 81 are vertically divided in the vertical direction. Further, the refrigerant passage 71 and the refrigerant passage 81 are located below the refrigerant passage 51 and the refrigerant passage 61 in the vertical direction.

The refrigerant passage 71 is a refrigerant pipe 146 that connects the distributor 973 and the heat pipe open end 701 of the heat transfer pipe 751, and then The heat exchanger tubes 751, 752, 753, 754, 755, 756 pass through the intermediate portion of the heat exchanger to reach the combiner 974 (the other end).

The refrigerant passage 81 is a refrigerant pipe 147 that connects the distributor 973 and the heat pipe opening 801 of the heat pipe 851, and then passes through the heat pipes 851, 852, 853, 854, 855, and 856 at the lower portion of the heat exchanger. The 974 is connected to the refrigerant passage 71.

In the manifold 954, the refrigerant passage 51 and the refrigerant passage 61 merge, and in the manifold 974, the refrigerant passage 71 and the refrigerant passage 81 merge, and the refrigerant pipe 148 and the refrigerant pipe 149 pass through the refrigerant pipe 149 to form a single refrigerant passage in the combiner 934. It is connected to the compressor 2 (refer to FIG. 1) through the refrigerant pipe 121.

In the second embodiment, the refrigerant pipe 142 and the refrigerant pipe 143 are connected by the communication pipe 991 in the middle of the refrigerant passage 31 and the refrigerant passage 41, and the refrigerant passage 31 communicates with the refrigerant passage 41. Further, in the middle of the refrigerant passage 51 and the refrigerant passage 61, the return pipe 111C (111) connecting the heat transfer pipe 552 and the heat transfer pipe 553, and the return pipe 111D (111) connecting the heat transfer pipe 652 and the heat transfer pipe 653 are provided. The refrigerant passage 51 is connected to the refrigerant passage 61 by being connected by the communication pipe 992. Further, in the middle of the refrigerant passage 71 and the refrigerant passage 81, the return pipe 111E (111) connecting the heat transfer pipe 752 and the heat transfer pipe 753, and the return pipe 111F (111) connecting the heat transfer pipe 852 and the heat transfer pipe 853 are provided. The refrigerant passage 71 is connected to the refrigerant passage 81 by being connected by the communication pipe 993.

Further, the communication pipe 991 is in the refrigerant pipes 142, 143 The outer peripheral surface (the outer peripheral side surface, the curved outer surface) 142b and 143b (see FIG. 8(b)) immediately after the refrigerant downstream side of the curved tubes 142a and 143a (see FIG. 8(b)) are connected to each other (see FIG. 8). The communication pipe 992 is connected to the outer circumferential surface (the outer circumferential side surface, the curved outer surface) 111b (see FIG. 6) of the curved pipe 111a of the return bend pipe 111C, and the outer circumferential surface of the curved pipe 111a of the return bend pipe 111D ( The outer peripheral side surface, the curved outer side surface 111b (see Fig. 6). The communication pipe 993 is connected to the outer circumferential surface (the outer circumferential side surface, the curved outer surface) 111b (see FIG. 6) of the curved pipe 111a of the return bend pipe 111E, and the outer circumferential surface of the curved pipe 111a of the return bend pipe 111F ( The outer peripheral side surface, the curved outer side surface 111b (see Fig. 6).

According to the heat exchanger (evaporator) of the second embodiment, as in the first embodiment, even if a plurality of refrigerant passages 31 and 41 (51, 61/71, 81) are vertically separated from each other in the vertical direction, The communication pipe 991 (992/993) is connected in the middle of the refrigerant passages 31, 41 (51, 61/71, 81), and the communication pipe 991 is connected to the refrigerant flows in the refrigerant pipes 142a, 143a adjacent to the curved pipes 142a, 143a. The outer peripheral surfaces 142b and 143b after the downstream side (the outer peripheral surface 111b of the curved tube 111a connecting the communicating tubes 992 and 993 to the return bends 111E and 111F) can improve the heat exchange performance.

Further, by the communication pipe 991, the state of the refrigerant before (upstream) of the distributor 953 and the state of the refrigerant before (upstream) of the distributor 973 become almost the same. Further, the communication passage 992 and the communication pipe 993 flow in the refrigerant passage 51, the refrigerant passage 61, the refrigerant passage 71, and the refrigerant passage 81. The moving refrigerant exhibits almost the same state change, and can exert the original heat exchange capacity of the evaporator to improve the performance of the air conditioner 1.

In this way, the difference in the degree of progress of the evaporation of the refrigerant between the refrigerant passages can be reduced, and the heat exchange performance as the evaporator and the machine performance of the air conditioner 1 can be improved. Furthermore, since the structures of the communication pipes 991, 992, and 993 are extremely simple, they can be manufactured at a relatively low cost.

Further, in the second embodiment, the communication pipe 990 is connected to the refrigerant passages 30 and 40 at a slightly the same distance from the distributor 11 (the refrigerant passages 31, 41, 51, 61, 71, 81 are both refrigerant passing through 2). After the heat pipe 110), the heat transfer area of the heat exchanger can be effectively utilized.

Further, in the second embodiment, the communication pipe 991 (992/993) is provided in a place where the pressure difference between the refrigerant passage 31 (51/71) and the refrigerant passage 41 (61/81) is increased, whereby The liquid refrigerant moves between the refrigerant passages, and the difference in the state of the refrigerant between the refrigerant passages can be reduced.

In the second embodiment, the connection pipe 992 (993) is connected to the outer circumferential side surface (the curved outer surface) of the return bend 111C (111E) and the return bend 111D (111F) (refer to FIG. 6) is an example, but is not limited thereto, and the communication pipes 992 and 993 may be connected to the position corresponding to FIG.

(Third embodiment)

Fig. 12 is a schematic side view showing the heat exchanger of the third embodiment. In addition, FIG. 12 discloses an example of an indoor heat exchanger for a home, and a broken line in FIG. The U-shaped pipe portion of the heat pipe (corresponding to the heat pipe 110 of Fig. 2), the thick arrow indicates the flow direction of the refrigerant when the heat exchanger functions as the evaporator (the air conditioner 3 functions as an evaporator during the cooling operation) The function is that when the outdoor heat exchanger 5 functions as a condenser, the flow direction of the refrigerant). Further, the piping shown by the thick solid line indicates the communication pipe 996 corresponding to the communication path in the patent application.

As shown in Fig. 12, the heat exchanger (evaporator) of the third embodiment includes a main heat exchanger M, a subcooler A, a subcooler B, and a two-way valve in a casing (not shown). 7. Distributors 931, 951, manifolds 932, 952, 962, 972. Further, the heat exchanger is disposed in the middle of the air passage from the air suction port (not shown) provided in the casing to the cross flow fan (not shown).

In the heat exchanger according to the third embodiment, the refrigerant pipe 123 connected to the decompressing device 4 (see FIG. 1) is connected to the heat pipe opening end 201 of the subcooler A. The single passage 23 from the open end 201 of the heat pipe passes through the subcooler A, the refrigerant pipe 130 connecting the subcooler A and the subcooler B, the subcooler B, and then reaches the outlet of the single passage 23. The heat pipe open end 206. Next, the heat pipe opening end 206 is connected to the distributor 931 through the refrigerant pipe 131.

Next, in the distributor 931, the refrigerant passage is divided into two. One of the refrigerant passages 33 passes through the refrigerant pipe 132 that connects the distributor 931 and the heat transfer pipe opening end 301 (one end), passes through the back side of the main heat exchanger M, and reaches the flow collector 932. The other refrigerant passage 43 is connected to the open end 401 (one end) of the heat pipe through the distributor 931. The refrigerant pipe 133 passes through the front upper side and the back side of the main heat exchanger M, reaches the flow collector 932, and merges with the refrigerant passage 33.

Thereafter, the refrigerant passage formed by the flow of the refrigerant passage 33 and the refrigerant passage 43 passes through the refrigerant pipe 134, the two-way valve 7, and the two-way valve 7 and the distributor 951 that connect the combiner 932 and the two-way valve 7. The connected refrigerant pipe 135 is then divided into four refrigerant passages 53, 63, 73, 83 at the distributor 951.

Further, the two-way valve 7 is actuated when the air conditioner 1 (see FIG. 1) is subjected to the dehumidifying operation, and has a current limiting function (decompression function). In the dehumidification operation, the refrigerant is not restricted by the decompression device 4 (see FIG. 1), but the refrigerant is restricted (decompressed) by the two-way valve 7 provided in the middle of the indoor heat exchanger 3 (see FIG. 1). The refrigerant is cooled by a heat exchanger downstream of the two-way valve 7, thereby removing moisture from the air. At this time, in the indoor heat exchanger 3 (see FIG. 1), the air heated by the high-temperature refrigerant passing through the heat exchanger on the upstream side of the two-way valve 7 and the heat exchanger passing through the downstream side of the two-way valve 7 The air cooled by the low-temperature refrigerant is mixed and discharged to the outside of the indoor heat exchanger 3 (see Fig. 1).

The refrigerant passage 53 is passed through a refrigerant pipe 136 that connects the distributor 951 to the open end 504 of the heat pipe, and then passes through the heat pipes 581, 582, and 583 at the intermediate portion of the front side of the main heat exchanger M, and reaches the combiner 962 (the other end) ).

The refrigerant passage 63 is a refrigerant pipe 137 that connects the distributor 951 and the open end 604 of the heat pipe, and then passes through the heat pipes 681, 682, and 683 at the intermediate portion of the front side of the main heat exchanger M to reach the manifold. 962, and merges with the refrigerant passage 53.

The refrigerant passage 73 passes through the refrigerant pipe 138 that connects the distributor 951 to the open end 703 of the heat transfer pipe, and then passes through the heat transfer pipes 781, 782, and 783 at the lower portion of the front side of the main heat exchanger M, and reaches the combiner 972 (the other end). .

The refrigerant passage 83 passes through the refrigerant pipe 139 that connects the distributor 951 and the open end 804 of the heat transfer pipe, and then passes through the heat transfer pipes 881, 882, and 883 at the lowermost portion on the front side of the main heat exchanger M, and reaches the manifold 972, and The refrigerant passages 73 merge.

In the manifold 962, the refrigerant passage 53 and the refrigerant passage 63 merge, and after the refrigerant passage 73 and the refrigerant passage 83 merge, the refrigerant passage 73 and the refrigerant passage 83 pass through the refrigerant pipe 151 and the refrigerant pipe 152, and after the manifold 952 becomes a single refrigerant passage. The refrigerant is supplied to the compressor 2 through the refrigerant pipe 124 (refer to FIG. 1). Further, the refrigerant passage 53 and the refrigerant passage 63 are vertically divided in the vertical direction, and the refrigerant passage 73 and the refrigerant passage 83 are vertically divided in the vertical direction.

In the third embodiment, in the middle of the refrigerant passage 53, the refrigerant passage 63, the refrigerant passage 73, and the refrigerant passage 83, the heat transfer pipe 581 and the heat transfer pipe 582 are connected to the return pipe 111M, and the heat transfer pipe 681 and the heat transfer pipe 682 are connected. The return bend 111N, the return bend 111O connecting the heat transfer pipe 781 and the heat transfer pipe 782, and the return bend 111P connecting the heat transfer pipe 881 and the heat transfer pipe 882 are connected by the communication pipe 996. Further, the communication pipe 996 is connected to the outer circumferential surface 111b of the bending pipe 111a of the return bend pipes 111M, 111N, 111O, and 111P (see FIG. 6).

As a result, in the refrigerant passage which is lowered by the communication pipe 996, the difference in the degree of progress of the evaporation of the refrigerant between the refrigerant passage 53 and the refrigerant passage 63 and the refrigerant passage 73 and the refrigerant passage 83 is reduced, and the original heat exchange capacity of the evaporator can be exhibited. It can improve the performance of the air conditioner 1.

(Fourth embodiment)

Fig. 13 is a schematic side view showing the heat exchanger of the fourth embodiment. In the fourth embodiment, the communication pipes 997, 998, and 999 are replaced with the communication pipes 996 in the third embodiment, and the same components as those in the third embodiment are denoted by the same reference numerals, and the description thereof will not be repeated. In addition, the communication pipes 997, 998, and 999 correspond to the communication paths in the scope of the patent application.

As shown in FIG. 13, the heat exchanger (evaporator) of the fourth embodiment is provided with a communication pipe 997 in the middle of the refrigerant passage 53 and the refrigerant passage 63, and is connected to a return pipe connecting the heat pipe 581 and the heat pipe 582. 111M, and a return pipe 111N connecting the heat pipe 681 and the heat pipe 682; and a communication pipe 998 in the middle of the refrigerant passage 73 and the refrigerant passage 83, which is connected to connect the heat pipe 781 and the heat pipe 782 The elbow 111O and the return pipe 111P connecting the heat pipe 881 and the heat pipe 882; and the communication pipe 999 in the middle of the refrigerant passage 63 and the refrigerant passage 73 are connected to connect the heat pipe 682 and the heat pipe 683 The return pipe 111Q and the return pipe 111R that connects the heat pipe 782 and the heat pipe 783.

In addition, the connecting pipes 997, 998, and 999 are all with the return bend The outer circumferential surface (the outer circumferential side surface, the curved outer surface) 111b (see FIG. 6) of the curved tube 111a of 111M, 111N, 111O, 111P, 111Q, and 111R communicates.

As a result, in the refrigerant passage 53, the refrigerant passage 63, the refrigerant passage 73, and the refrigerant passage 83, the change in the state of the refrigerant is almost the same by the communication pipe 997, the communication pipe 998, and the communication pipe 999, whereby the evaporation can be promoted as evaporation. The heat exchange performance of the device can be improved as the air conditioner 1.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention. For example, in each of the embodiments, as a method of connecting the communication pipes, a plurality of types may be selected from the first installation mode to the fourth installation mode.

11‧‧‧Distributor

12‧‧‧Converter

30, 40‧‧‧ refrigerant passage

100‧‧‧Fins

110‧‧‧U-shaped heat pipe (thermal path)

111a‧‧‧Bending tube (bending path)

111b‧‧‧Outer surface (outer side)

111, 111A, 111B‧‧‧rebound tube

110a, 110b‧‧‧ entrance

110c, 110d‧‧‧Export

990‧‧‧Connected pipe (connected road)

P‧‧‧Distribution point for distributor 11

Claims (4)

An air conditioner characterized by comprising: at least a compressor, a compression refrigerant; a condenser for condensing a refrigerant compressed by the compressor; and a pressure reducing device for decompressing the refrigerant condensed in the condenser; and evaporating The evaporator evaporates the refrigerant under reduced pressure in the decompressing device; the evaporator has a plurality of refrigerant passages, at least a portion of which is vertically divided vertically; and a distributor, one of the two ends of the plurality of refrigerant passages, the refrigerant Diverting to the plurality of refrigerant passages; the other of the two ends of the plurality of refrigerant passages, the refrigerant flowing through the plurality of refrigerant passages; and the communication passage connecting the plurality of refrigerant passages; The refrigerant passage has a heat conduction passage extending in a horizontal direction and performing heat exchange, and a curved passage that is separated from the heat conduction passage and returned to the other heat conduction passage; the communication passage is in the middle of the refrigerant passage and the outer circumference of the curved passage The sides are connected. An air conditioner characterized by comprising: at least a compressor, a compression refrigerant; a condenser for condensing a refrigerant compressed by the compressor; and a pressure reducing device for decompressing the refrigerant condensed by the condenser; and The evaporator evaporates the refrigerant decompressing the decompressing device; the evaporator has: a plurality of refrigerant passages, at least a portion of which is vertically divided vertically; and a distributor, one of the two ends of the plurality of refrigerant passages The refrigerant is branched to the plurality of refrigerant passages; the other of the two ends of the plurality of refrigerant passages is configured to merge the refrigerant flowing through the plurality of refrigerant passages; and the communication passage connects the plurality of refrigerant passages; The refrigerant passage has a heat conduction passage extending in a horizontal direction and performing heat exchange, and a curved passage that is separated from the heat conduction passage and returned to the other heat conduction passage; the communication passage is in the middle of the refrigerant passage and adjacent to the curved passage The surface of the outer peripheral side after the downstream flow measurement of the refrigerant is connected. The air conditioner according to claim 1 or 2, wherein the communication passage is located at a distance slightly shorter than the distributor in the refrigerant passage. An air conditioner according to claim 1 or 2, wherein the communication passage is disposed between the refrigerant passages having different heights.