CN113587251B

CN113587251B - Air conditioner

Info

Publication number: CN113587251B
Application number: CN202110845581.9A
Authority: CN
Inventors: 赵东方; 曹法立; 石丽华; 刘晓蕾; 李晓宇
Original assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Current assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority date: 2021-07-26
Filing date: 2021-07-26
Publication date: 2022-11-15
Anticipated expiration: 2041-07-26
Also published as: CN113587251A

Abstract

The invention provides an air conditioner which can solve the problems that in the prior art, a multi-row micro-channel heat exchanger has many welding spots, is easy to generate refrigerant leakage risk and has low production efficiency. The air conditioner comprises a multi-flat-tube parallel flow heat exchanger, the multi-flat-tube parallel flow heat exchanger comprises an inner-row heat exchanger and an outer-row heat exchanger, the flat tubes are U-shaped, the air conditioner also comprises a flow divider, a connector and a gas collecting tube, the connector is used for correspondingly communicating the flat tubes of the inner-row heat exchanger and the flat tubes of the outer-row heat exchanger, the second ends of the flat tubes of the inner-row heat exchanger are connected to the connector, and the second ends of the flat tubes of the outer-row heat exchanger are connected to the connector; the first end of the flat tube of the external heat exchanger is connected with the gas collecting tube. The air conditioner can realize the communication of the inner and outer heat exchangers and the uniform distribution of gas-liquid two-phase refrigerants, greatly simplifies the structure of the heat exchanger and the welding points of the heat exchanger, reduces the leakage points of the refrigerants and improves the production and assembly efficiency.

Description

Air conditioner

Technical Field

The invention relates to the technical field of air conditioners, in particular to an air conditioner.

Background

In order to reduce the production cost of the air-conditioning heat exchanger, part of manufacturers already start to produce all-aluminum heat exchangers, and compared with the traditional finned tube heat exchanger, the cost of the heat exchanger materials can be reduced by 40% because copper tubes are not used. The micro-channel parallel flow heat exchanger is a common all-aluminum heat exchanger, a plurality of flat pipes are arranged in the vertical direction of the heat exchanger, the flat pipes are directly connected through collecting pipes, fins are arranged among the flat pipes and used for reinforcing heat exchange with air, and the common micro-channel heat exchanger is shown in figure 1 and comprises a collecting pipe 1, flat pipes 2 and fins 3.

In order to improve the heat exchange efficiency, some air conditioners may employ a multi-row micro-channel heat exchanger, such as a double-row micro-channel heat exchanger or a three-row micro-channel heat exchanger, that is, two rows or three rows of flat tubes are correspondingly arranged along the air flow direction, and each row is provided with a plurality of flat tubes at intervals from top to bottom, which is described by taking a prior art double-row micro-channel heat exchanger as an example as shown in fig. 2. As shown in fig. 2, for a double-row heat exchanger, the double-row heat exchanger generally includes four collecting pipes, that is, a first collecting pipe 4 and a second collecting pipe 5 which are located at an outer row, and a third collecting pipe 6 and a fourth collecting pipe 7 which are located at an inner row, the first collecting pipe 4 and the second collecting pipe 5 are respectively communicated with two ends of an outer row flat pipe 8, the third collecting pipe 6 and the fourth collecting pipe 7 are respectively communicated with two ends of an inner row flat pipe 9, and the outer row flat pipe 8 and the inner row flat pipe 9 are connected into a whole by a same group of fins to enhance heat exchange with air.

For a dual-row heat exchanger, there must be cross-row flow during refrigerant operation. For example, during heating operation, the refrigerant flows into one flow path of the outer heat exchanger (for example, 6 outer flat discharge pipes 6) through the first collecting pipe 4, reaches the second collecting pipe 5, and flows out of the second collecting pipe 5 again, and there are two flow modes after flowing out of the second collecting pipe 5 according to different flow paths:

one is that the refrigerant flows upwards or downwards and still flows outwards, returns to the first collecting pipe 4 and then enters the fourth collecting pipe 7, and the flowing mode in the fourth collecting pipe 7 is the same as that of the first collecting pipe 1;

alternatively, the flow from the second header 5 to the third header 6 requires a cross-row connection.

Because the all-aluminum heat exchanger generally welds in the tunnel furnace, the multirow heat exchanger of this kind of current many pressure manifolds can lead to the solder joint numerous, for example, flat pipe quantity is 60, then double heat exchanger only the solder joint between pressure manifold and the flat pipe just reaches 272, welding process in the stove has proposed higher requirement simultaneously, if there is the connecting pipe between the row of striding, the connecting pipe can not be installed before the welding in the tunnel furnace, need bend again after the welding completion in the tunnel furnace, the manual welding of connecting pipe is carried out again after bending, required labour is long, low in production efficiency, and probably influence welding quality.

Disclosure of Invention

The invention provides an air conditioner which can solve the problems that in the prior art, a multi-row micro-channel heat exchanger has many welding spots, is easy to generate refrigerant leakage risk and has low production efficiency.

In some embodiments of the present application, an air conditioner is provided, including a multi-flat-tube parallel flow heat exchanger, where the multi-flat-tube parallel flow heat exchanger includes an outer row heat exchanger and an inner row heat exchanger arranged along an air flow direction, the inner row heat exchanger includes a plurality of flat tubes, and the outer row heat exchanger includes a plurality of flat tubes in one-to-one correspondence with the flat tubes of the inner row heat exchanger; the method is characterized in that:

the flat tubes are all U-shaped and comprise an upper horizontal section, a lower horizontal section and a bending part for connecting the upper horizontal section and the lower horizontal section, the free end of the upper horizontal section is a flat tube first end, and the free end of the lower horizontal section is a flat tube second end;

the multi-flat-tube parallel flow heat exchanger further comprises:

the flow divider is used for distributing the gas-liquid two-phase refrigerant to each flat tube of the outer heat exchanger, and the first end of the flat tube of the outer heat exchanger is connected to the flow divider;

the connector is provided with a plurality of connectors, the connectors are arranged in one-to-one correspondence with the flat tubes of the outer heat exchanger and are used for correspondingly communicating the flat tubes of the outer heat exchanger and the flat tubes of the inner heat exchanger, the second ends of the flat tubes of the outer heat exchanger are connected to the connectors, and the second ends of the flat tubes of the inner heat exchanger are connected to the connectors;

and the first end of the flat tube of the inner row heat exchanger is connected to the gas collecting tube.

The utility model provides an air conditioner, among its many flat pipe parallel flow heat exchangers, the flat pipe of interior row heat exchanger and outer heat exchanger all is the U-shaped form, then only need set up shunt and 1 discharge, can realize the intercommunication of interior outer heat exchanger of arranging and the evenly distributed of the double-phase refrigerant of gas-liquid, the heat exchanger structure has been simplified greatly, and the discharge is located the heat exchanger gas side, also need not to utilize the baffle to divide the flow path in the discharge is inside, adopt a siphunculus can, the solder joint of the heat exchanger has significantly reduced, the refrigerant leakage point has been reduced, and production assembly efficiency has been improved.

In some embodiments of the present application, the connector includes a housing and a flat communication flow passage formed in the housing, the flat communication flow passage has two inlet/outlet ports penetrating through the housing, one of the inlet/outlet ports communicates with the second end of the flat tube of the outer heat exchanger, and the other inlet/outlet port communicates with the second end of the flat tube of the inner heat exchanger.

In some embodiments of the present application, the cross-sectional dimension of the flat communication flow passage is matched with the cross-sectional dimension of the flat pipe.

In some embodiments of the present application, a reinforcing rib is provided in the flat communication flow passage.

In some embodiments of this application, the discharge is a both ends are sealed, inside siphunculus that link up, be provided with on the body with the connector that interior row heat exchanger's flat pipe first end corresponds and is connected.

In some embodiments of the present application, the multi-flat-tube parallel flow heat exchanger further comprises a main air tube assembly for connecting the air collecting tube with the refrigeration system.

In some embodiments of the present application, the main air tube assembly includes a main air tube and a plurality of branch air tubes communicated with the main air tube, the branch air tubes are arranged along an extending direction of the main air tube, the branch air tubes are connected with the gas collecting tube, one end of the main air tube is closed, and the other end of the main air tube is a connecting end for connecting with a refrigeration system.

In some embodiments of the present application, the number of the diverters is multiple, and each of the diverters corresponds to one of the flat tubes of the outer heat exchanger; the multi-flat-tube parallel flow heat exchanger further comprises a liquid tube assembly used for connecting the plurality of shunts with the refrigerating system.

In some embodiments of this application, the liquid pipe subassembly include main liquid pipe, branch liquid head and with a plurality of branch liquid pipes that the shunt quantity is the same, main liquid pipe one end be used for with refrigerating system throttle mechanism intercommunication, the other end with branch liquid head connection, it is a plurality of the entrance point of branch liquid pipe is all connected on the branch liquid head, and is a plurality of the exit end and a plurality of branch liquid pipe the shunt one-to-one is connected.

In some embodiments of the present application, the flow splitter comprises:

the flow divider comprises a flow divider main body, a flow divider main body and a flow divider, wherein a flat flow passage is formed in the flow divider main body and extends along the arrangement direction of flat tubes of the outer heat exchanger;

a refrigerant inlet provided in the flow divider main body and communicating with the flat flow channel on one side surface in the thickness direction of the flat flow channel;

the refrigerant outlets are arranged on the splitter main body and communicated with the flat flow channel on the other side face in the thickness direction of the flat flow channel, and the refrigerant outlets are distributed along the extension direction of the flat flow channel.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a perspective view of a prior art microchannel heat exchanger;

FIG. 2 is a schematic diagram of a prior art dual-row heat exchanger configuration;

FIG. 3 is a perspective view of a heat exchanger in a first embodiment of the air conditioner of the present invention;

FIG. 4 is an enlarged view of section I of FIG. 3;

FIG. 5 is a schematic diagram of a heat exchanger with fins and flat tubes according to a first embodiment of the air conditioner of the present invention;

FIG. 6 is a perspective view of a connector in accordance with one embodiment of the air conditioner of the present invention;

FIG. 7 is a perspective view of a main air duct assembly in an embodiment of the air conditioner of the present invention;

FIG. 8 is a perspective view of a liquid pipe assembly in accordance with an embodiment of the air conditioner;

FIG. 9 is a perspective view of a heat exchanger splitter according to one embodiment of the air conditioner of the present invention;

FIG. 10 is an exploded view of FIG. 9;

FIG. 11 is a front view in the direction A of FIG. 9;

FIG. 12 is a sectional view taken along line B-B of FIG. 11;

FIG. 13 is a front view in the direction of C of FIG. 11;

FIG. 14 is a cross-sectional view D-D of FIG. 13;

FIG. 15 is a cross-sectional view of a heat exchanger splitter in a second embodiment of the air conditioner of the present invention;

FIG. 16 is an enlarged view of section E of FIG. 5;

FIG. 17 is a perspective view of an end cap of a splitter according to a second embodiment of the air conditioner of the present invention;

FIG. 18 is a front view F of FIG. 17;

FIG. 19 is a sectional view taken along line G-G of FIG. 18;

FIG. 20 is an enlarged view of section H of FIG. 19;

fig. 21 is a schematic view showing the flow direction of the two-phase gas-liquid refrigerant flow in the flow divider according to the second embodiment of the air conditioner of the present invention.

Reference numbers in fig. 1 to 2:

1-collecting pipe; 2-flat tube; 3-a fin; 4-a compressor; 5-outdoor heat exchanger; 6-a throttling mechanism; 7-indoor side heat exchanger; a 8-four-way valve;

reference numbers in fig. 3:

1-a first header; 2-a second header; 3-a third header; 4-a fourth header; 5-a fin; 6-flat discharge tubes; 7-inner flat discharge pipes;

reference numerals in fig. 4 to 20:

10-an external heat exchanger; 20-inner row heat exchanger;

100-flat tube; 110-a first end; 120-a second end; 130-a bending part; 140-an upper horizontal section; 150-a lower horizontal section;

200-a shunt; 210-a shunt body; 211-flat flow channel; 211A-a thickness direction first side; 211 A1-a first sub-side; 211 A2-second sub-side; 211B-a thickness direction second side; 212-end cap portion; 213-a body portion; 214-annular positioning groove; 220-a refrigerant inlet; 230-a refrigerant outlet; 240-arc shaped recess;

300-a fin;

400-a connector; 410-a housing; 420-flat connected flow channel; 421-inlet/outlet;

500-a gas collecting pipe;

600-main gas tube assembly; 610-main air pipe; 611-a connection end; 620-bronchus;

700-a liquid tube assembly; 710-main liquid pipe; 720-shunting head; 730-Branch liquid tube.

Detailed Description

The technical scheme of the invention is clearly and completely described in the following with reference to the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in a specific case to those of ordinary skill in the art.

Furthermore, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The air conditioner performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve, and an evaporator in the present application. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

The compressor compresses a refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

The expansion valve expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid-phase refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a cooling effect by heat-exchanging with a material to be cooled using latent heat of evaporation of a refrigerant. The air conditioner can adjust the temperature of the indoor space throughout the cycle.

An outdoor unit (outdoor unit) of an air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, an indoor unit (indoor unit) of an air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

The indoor heat exchanger and the outdoor heat exchanger serve as a condenser or an evaporator. When the indoor heat exchanger is used as a condenser, the air conditioner is used as a heater in a heating mode, and when the indoor heat exchanger is used as an evaporator, the air conditioner is used as a cooler in a cooling mode.

Example one

Referring to fig. 3 to 5, an air conditioner according to the present embodiment includes a multiple flat tube parallel flow heat exchanger including an outer row heat exchanger 10 and an inner row heat exchanger 20 arranged along an air flow direction, the air flow direction is shown by an arrow indicating a flow direction of air in fig. 3, and a dotted line on a fin 300 in fig. 3 indicates a boundary line between the outer row heat exchanger 10 and the inner row heat exchanger 20. The air conditioner of the present embodiment further includes a flow divider 200, a connector 400, and a collecting duct 500. Outer heat exchanger 10 includes a plurality of flat pipes 100, and interior heat exchanger 20 includes a plurality of flat pipes 100 with outer heat exchanger 10's flat pipe 100 one-to-one, and many flat pipe parallel flow heat exchangers still include fin 300 certainly.

The flat tubes 100 are arranged in rows at intervals up and down along the height direction of the heat exchanger, and the distance between every two adjacent flat tubes 100 is 10-18mm. A plurality of microchannels for circulating refrigerants are formed in the flat tube 100, the flat tube 100 is arranged in the fin 300 in a penetrating mode, the flowing direction of air flowing through the fin 300 is perpendicular to the flowing direction of the refrigerants flowing through the flat tube 100, heat/cold energy released by the refrigerants in the flat tube is taken away through heat dissipation of the fin 300 and air flow, and heat exchange with air is enhanced.

The flat tube 100 is made of porous micro-channel aluminum alloy, and the fin 300 is made of aluminum alloy with a brazing composite layer on the surface, so that the flat tube is light in weight and high in heat exchange efficiency.

In this embodiment, outer heat exchanger 10 and interior flat tube 100 of arranging heat exchanger 20 all buckle and be the U-shaped, including upper portion horizontal segment 140, lower part horizontal segment 150 and kink 130, kink 130 is located the same one side of upper portion horizontal segment 140 and lower part horizontal segment 150 and connects upper portion horizontal segment 140 and lower part horizontal segment 150, and flat tube 100 has both ends, and the free end of upper portion horizontal segment 140 is flat first end 110, and the free end of lower part horizontal segment 150 is flat second end 120.

The flow divider 200 is used to distribute the gas-liquid two-phase refrigerant to each flat tube 100 of the outer heat exchanger 10, and the first end 110 of each flat tube of the outer heat exchanger 10 is connected to the flow divider 200.

The number of the connectors 400 is plural, the connectors are arranged in one-to-one correspondence with the flat tubes 100 of the outer heat exchanger 10 and are used for correspondingly communicating the flat tubes 100 of the outer heat exchanger 10 and the flat tubes 100 of the inner heat exchanger 20, the flat tube second end 120 of the outer heat exchanger 10 is connected to the connector 400, and the flat tube second end 120 of the inner heat exchanger 20 is connected to the connector 400, so that the connector 400 realizes the cross-row flow of the refrigerant between the two heat exchangers, the flat tube first end 110 of the outer heat exchanger 10 is the refrigerant inlet end thereof, the flat tube second end 120 of the outer heat exchanger 10 is the refrigerant outlet end thereof, the flat tube second end 120 of the inner heat exchanger 20 is the refrigerant inlet end thereof, the flat tube first end 110 is the refrigerant outlet end thereof, and the flat tube first ends 110 of the inner heat exchanger 20 are all connected to the gas collecting tube 500.

This application air conditioner, among its many flat tub of parallel flow heat exchangers, the flat pipe of interior row heat exchanger and outer heat exchanger all is the U-shaped form, then only need set up shunt and 1 discharge, can realize the intercommunication of interior outer heat exchanger and the evenly distributed of the two-phase refrigerant of gas-liquid, the heat exchanger structure has been simplified greatly, and the discharge is located the heat exchanger gas side, also need not to utilize the baffle at the discharge inside to divide the flow path, adopt a siphunculus can, the solder joint of the heat exchanger that has significantly reduced, the refrigerant leakage point has been reduced, and production assembly efficiency has been improved.

Specifically, with respect to the connector 400, referring to fig. 4 and 6, it includes a housing 410 and a flat communication flow passage 420 formed in the housing 410, the flat communication flow passage 420 having two inlet/outlet ports 421 penetrating through the housing 410, wherein one inlet/outlet port 421 communicates with the flat tube second end 120 of the outer row heat exchanger 10, and the other inlet/outlet port 421 communicates with the flat tube second end 120 of the inner row heat exchanger 20.

Further, the cross-sectional dimension of the flat communication channel 420 is matched with that of the flat tube 100, so as to facilitate the sealed communication between the two.

In order to prevent the connector 400 from deforming due to insufficient pressure bearing caused by over-high pressure of the refrigeration system, a reinforcing rib 430 is provided in the flat communication flow passage 420 in this embodiment to support the connector, as shown in fig. 6.

For the gas collecting pipe 500, which is a collecting pipe after all refrigerants finally flow out from the heat exchange flat pipes 100, when the air collecting pipe 500 performs refrigeration operation, the gas collecting pipe 500 is communicated with the compressor to exhaust, and high-temperature and high-pressure exhaust is evenly distributed to each flat pipe 100 from the gas collecting pipe 500.

Because the gas collecting pipe 500 runs through the whole heat exchanger in the height direction and is limited by the frame structure of the heat exchanger, usually, no extra space is provided to directly connect the gas collecting pipe 500 with the refrigeration system, and in order to connect the gas collecting pipe 500 with the refrigeration system, the multi-flat-pipe parallel flow heat exchanger 10 in this embodiment further includes a main gas pipe assembly 600 as a transition connection pipe between the refrigeration system and the gas side of the whole heat exchanger, and connects the gas collecting pipe 500 with the refrigeration system.

Specifically, referring to fig. 7, the main air duct assembly 600 includes a main air duct 610 and a plurality of branch air ducts 620 each directly communicating with the main air duct 610, the plurality of branch air ducts 620 are arranged at intervals along an extending direction of the main air duct 610, that is, an extending direction of the header 500 and a height direction of the heat exchanger, and are all connected to the header 500, one end of the main air duct 610 is closed, and the other end is a connection end 611 for connecting to a refrigeration system, thereby connecting the header 500 to the refrigeration system.

When the multi-flat-tube parallel flow heat exchanger 10 of the air conditioner is large in size and high in height, which results in a large number of flat tubes 100, a plurality of shunts 200 are usually provided, and each shunt 200 has 4 or 6 refrigerant outlets 230, that is, the shunt is combined with 4 or 6 flat tubes 100 of the outer heat exchanger 10, so as to avoid deformation and assembly errors caused by the fact that all flat tubes 100 are connected to one shunt 200 as much as possible. Also receive the restriction of heat exchanger frame structure, also can have not extra space and make the problem that a plurality of shunts 200 are direct to link to each other with refrigerating system, for solving this problem, the multi-flat pipe parallel flow heat exchanger 10 still includes liquid pipe assembly 700 in this embodiment, as the transitional coupling nest of tubes of refrigerating system and whole heat exchanger liquid side.

Specifically, referring to fig. 8, the liquid pipe assembly 700 includes a main pipe 710, a branch pipe 720 and a plurality of branch pipes 730, the main pipe 710 has one end communicating with the throttling mechanism and the other end connected to the branch pipe 720, the inlet ends of the plurality of branch pipes 730 are all connected to the branch pipe 720, and the outlet ends of the plurality of branch pipes 730 are connected to the refrigerant inlet 220 of the flow divider 200 in a one-to-one correspondence manner.

In addition, in the prior art, because the heat exchanger of the commercial air conditioner is very large, the height of the heat exchanger is generally more than 800mm, statistics shows that the distance between the flat tubes is more than 10 to 18mm, the number of the flat tubes in the vertical direction is often more than 60, and whether the refrigerant can be uniformly distributed among the flat tubes becomes a bottleneck problem which restricts the performance of the microchannel heat exchanger.

As is well known, the principle of the cooling and heating system of an air conditioner is as follows: during the refrigeration operation, the refrigerant is compressed by the work of the compressor to become high-temperature and high-pressure superheated gas, the gas is discharged into the outdoor heat exchanger for condensation, and the refrigerant is superheated gas, so that the problem of flow distribution does not exist generally, and the refrigerant can be uniformly distributed at the inlet of the outdoor heat exchanger generally; the refrigerant is cooled into supercooled liquid in the outdoor heat exchanger, enters the throttling mechanism, is throttled into low-temperature and low-pressure two-phase refrigerant, flows into the indoor heat exchanger to be evaporated and absorb heat, is evaporated into superheated gas in the indoor heat exchanger, and returns to the suction end of the compressor to complete a cycle.

When in heating operation, high-temperature and high-pressure refrigerant gas is directly discharged into the indoor side heat exchanger through the four-way valve to be heated, after being cooled into supercooled liquid in the indoor side heat exchanger, the refrigerant gas is throttled into low-temperature and low-pressure gas-liquid two-phase refrigerant by the throttling mechanism, the two-phase refrigerant enters the outdoor side heat exchanger to be evaporated and absorbed, and the phenomenon of uneven distribution caused by phase separation can exist when two-phase flow is in a large space or the flow rate is reduced, so that a liquid separating mechanism needs to be arranged at a liquid side inlet of the outdoor side heat exchanger, the flow of the refrigerant entering each heat exchange tube (flat tube in the application) of the outdoor side heat exchanger is ensured to be basically consistent, and the maximum effect of the heat exchanger is exerted.

Uneven distribution of the gas-liquid two-phase refrigerant entering the outdoor heat exchanger can cause the performance of the heat exchanger to be reduced sharply.

To solve this problem, heat exchanger manufacturers often make articles inside the collector, for example by adding baffles or by using more complex structures. The flat pipes are separated by the partition plates, for example, 6 flat pipes are in one group, the effect is better only under the condition of full load and large flow, and when the compressor is in partial load, the rotating speed of the compressor is extremely low, the flow rate of the refrigerant is also very low, the phase separation condition is serious, and the effect of uniform shunting cannot be achieved. Some of the devices use very complicated structures, and the fluid is rotated by the complicated structure design to reduce the probability of gas-liquid phase separation, so that the structure design and the manufacturing process are very difficult, and the phase separation phenomenon still exists at small flow.

In the present embodiment, in order to improve the distribution uniformity of the gas-liquid two-phase refrigerant entering each flat tube of the outdoor heat exchanger, a flow divider 200 is provided to distribute the gas-liquid two-phase refrigerant fluid uniformly among each flat tube 100 of the outdoor heat exchanger 10. Referring to fig. 9 to 14, the flow divider 200 specifically includes a flow divider body 210, a refrigerant inlet 220, and a plurality of refrigerant outlets 230.

A flat flow channel 211 is formed in the diverter main body 210, so that the diverter main body 210 is of a hollow structure, the flow channel space thickness of the flat flow channel 211 is very small and thin, as shown in fig. 12, a dimension a is the thickness of the flat flow channel 220, and the flat flow channel 211 extends along the arrangement direction of the plurality of flat tubes 100 of the outer row heat exchanger 10, that is, in this embodiment, along the height direction, that is, the up-down direction, of the multi-flat-tube parallel flow heat exchanger, as shown in fig. 12. In this embodiment, the flow divider main body 210 is a thin rectangular shape, the length direction of the flow divider main body is the same as the extending direction of the flat flow channel 220, for manufacturing convenience, the flow divider main body 210 is further divided into an end cover part 212 and a main body part 213, the refrigerant inlet 220 is formed on the end cover part 212, the refrigerant outlet 230 is formed on the main body part 213, a shallow groove is formed inside the main body part 213, and meanwhile, an annular positioning groove 214 matched with the end cover part 212 is provided, the end cover part 212 is fittingly embedded in the annular positioning groove 214 and is fixed with the main body part 213 in a sealing manner, and the outer surface of the end cover part 212 after installation is flush with the corresponding side surface of the main body part 213 to jointly enclose the flat flow channel 211 inside.

The refrigerant inlet 220 is provided on the flow divider main body 210 and communicates with the flat flow channel 220 on one side surface in the thickness direction of the flat flow channel 220, as shown in fig. 12, the dimension a is the thickness of the flat flow channel 220, and the direction of the dimension a is the thickness direction of the flat flow channel 220, and at the same time, as viewed from fig. 12, the refrigerant inlet 220 is located on the left side surface of the flat flow channel 211 and communicates with the flat flow channel 211. The refrigerant inlet 220 is embodied as an inlet pipe formed at the end cover portion 212, and the throttled gas-liquid two-phase refrigerant fluid with a certain dryness is connected to the refrigerant inlet 220 through a capillary tube of the liquid tube assembly 700.

The plurality of refrigerant outlets 230 are used for being connected with the plurality of flat tubes 100 of the outer heat exchanger 10 in a one-to-one correspondence manner, so that the gas-liquid two-phase refrigerant fluid uniformly distributed by the flow divider 200 flows into the corresponding flat tubes 100. The refrigerant outlet 230 is a long strip-shaped flat opening to be fittingly connected to the flat tube 100, is provided on the flow divider main body 210, and is communicated with the flat flow channel 211 on the other side surface in the thickness direction of the flat flow channel 211, and the plurality of refrigerant outlets 230 are arranged along the extending direction of the flat flow channel 211. The refrigerant outlet 230 is specifically a short flat microchannel tube exposed outside the splitter body 210 so as to be fittingly connected to the flat tube 100, and the refrigerant outlet 230 is located on the right side of the flat flow channel 211 and communicates with the flat flow channel 211 as viewed in fig. 12.

The air conditioner of the application, the principle that the flow divider 200 can evenly distribute the gas-liquid two-phase refrigerant fluid is as follows: the gas-liquid two-phase refrigerant fluid flowing at high speed flows into the flat flow channel 211 from the refrigerant inlet 220, and because the flat flow channel 211 is a flat thin-layer space, the gas-liquid two-phase refrigerant fluid can be quickly spread when touching one side surface (the right side surface of the flat flow channel 211 in fig. 12) in the thickness direction of the flat flow channel 211, and then uniformly flows into each refrigerant outlet 230, and the fluid flows as shown by arrows in fig. 12, because the flat flow channel 211 is thin, the fluid can still keep a high flow rate after spreading, the high flow rate can greatly inhibit the influence of gravity, so that the gas-liquid two-phase refrigerant has no chance of gas-liquid phase separation, and the refrigerant fluid flow distribution flowing around the refrigerant inlet 220 is almost equal; meanwhile, because the flat flow channel 211 is flat and thin, the gas-liquid two-phase refrigerant basically has no space for phase separation, and the effect of uniform flow distribution is further improved.

In addition, the flow divider 200 does not need to be provided with a partition plate inside to divide a flow path, and has the advantages of simple structure, low cost and convenience in processing.

In this embodiment, as shown in fig. 12 and 14, the thickness a of the flat flow channel 211 ranges from 1 mm to 3mm, the width b ranges from 10 mm to 22mm, and the length h ranges from 50 mm to 100mm, so that the flat flow channel forms a flat and thin space.

In the present embodiment, the length m of the inner contour (i.e., the contour corresponding to the inner diameter) of the refrigerant outlet 230 ranges from 10 to 22mm, and the width n of the inner contour ranges from 1.5 to 3mm.

As shown in fig. 9, 10, 12 to 14, the inner width direction of refrigerant outlet 230 is parallel to the extending direction of flat flow channel 211, i.e. the inner width n of refrigerant outlet 230 is parallel to the length h direction of flat flow channel 211, so that a plurality of refrigerant outlets 230 are arranged along the extending direction of flat flow channel 211, and the length and volume of flow divider 200 are reduced as much as possible without changing the number of flat tubes 100. In addition, the refrigerant outlet 230 and the refrigerant inlet 220 are arranged in a staggered manner, so that the refrigerant flowing at a high speed is prevented from directly entering the refrigerant outlet 230 directly opposite to the refrigerant inlet 220 after entering the flat flow channel 211 from the refrigerant inlet 220, the uniform spreading of the refrigerant is influenced, and meanwhile, the refrigerant outlet 230 is correspondingly arranged at both ends of the flat flow channel 211 in the extending direction, so that fluid flowing dead angles are prevented from existing at both ends of the flat flow channel 211 in the extending direction.

In the present embodiment, the refrigerant inlet 220 faces the center of the flat flow channel 211, specifically, is located at the center of the flow divider body 210, and the plurality of refrigerant outlets 230 are arranged at equal intervals along the extending direction of the flat flow channel 211. Therefore, on one hand, the flow divider 210 is symmetrical in structure, the fool-proof design is realized, and on the other hand, the uniform fluid distribution is further facilitated.

In summary, in the air conditioner of the present embodiment, during heating operation, the refrigerant is throttled by the throttling mechanism from the refrigeration system to become a low-temperature and low-pressure gas-liquid two-phase refrigerant, the two-phase refrigerant enters the liquid pipe assembly 700, and because the cross-sectional area of the flow channel in the branch pipe 730 is small, phase separation is difficult to occur, so it is considered that the two-phase refrigerant can be uniformly distributed to each branch pipe 730, the branch pipe 730 is connected to the flow divider 200, the two-phase refrigerant is uniformly distributed to each flat pipe 100 in the inner row in the flow divider 200, the refrigerant flows from the flow dividing side (the side defining the heat exchanger configuration flow divider 200 is called the flow dividing side, and the side where the bending portion 130 of the flat pipe 100 is located is the tail side) to the tail side in the flat pipe 100 in the inner row, and flows to the flow dividing side again through the bending portion 130 on the tail side, and then flows into the flat pipe 100 in the rear row through the connector 400, returns again through the bending portion 130, finally flows into the gas pipe 500, and then flows into the compressor suction end of the main gas pipe assembly 600 of the refrigeration system, thereby completing a heating process. As the refrigerant flows from the first end (i.e., the inlet end) of the inner row of flat tubes 100, it begins to absorb heat, and as the flow progresses, the refrigerant gradually vaporizes and increases in quality, and reaches the outlet of the main air tube assembly 600, and is generally heated to a superheated gas.

During the cooling operation, the high-temperature and high-pressure compressor exhaust firstly exhausts the main gas pipe assembly 600, because the gas state is adopted, the pressure distribution is relatively uniform, the refrigerant can be uniformly distributed in each branch gas pipe 620 and further uniformly distributed in the gas collecting pipe 500, the refrigerant state is unchanged in the gas collecting pipe 500, and the refrigerant is also high-temperature and high-pressure superheated gas, so the refrigerant can be relatively easily distributed in each flat pipe 100 at the rear row, at the moment, the refrigerant flows once according to the reverse process of the heating operation, exchanges heat with outside air and is gradually cooled into supercooled liquid (the liquid pipe assembly 700) by the air, and because the refrigerant distributed in the cooling operation is high-temperature and high-pressure gas, the problem of difficult refrigerant distribution is rarely involved.

Example two

Referring to fig. 15 to 21, in the present embodiment, for convenience of description, a side surface of the flat flow channel 211 communicating with the refrigerant inlet 220 is defined as a first side surface 211A in the thickness direction of the flat flow channel 211, and the other side surface communicating with the refrigerant outlet 230 is defined as a second side surface 211B in the thickness direction of the flat flow channel 211.

Unlike the first embodiment, in the present embodiment, along the extending direction of flat flow channel 211, thickness direction first side surface 211A is composed of first sub-side surface 211A1 located on one side of refrigerant inlet 220 and second sub-side surface 211A2 located on the other side of refrigerant inlet 220, and both first sub-side surface 211A1 and second sub-side surface 211A2 are inclined to the side where refrigerant inlet 220 is located.

The reason for this design is that when a gas-liquid two-phase refrigerant fluid flowing at a high speed flows in through the refrigerant inlet 220 and hits the second side surface 211B in the thickness direction of the flat flow channel 211, the fluid turns 90 ° and flows in a flat manner around, which may cause a large pressure loss, thereby causing flash of the refrigerant at this position, and further aggravating the pressure loss after the gas phase ratio is increased, which may adversely affect the improvement of the refrigeration performance, so in this embodiment, the first sub-side surface 211A1 and the second sub-side surface 211A2 of the first side surface 211A in the thickness direction of the flat flow channel 211 are both inclined toward the side where the refrigerant inlet 220 is located, so that the cross section of the flat flow channel 211 is changed, and when the fluid turns to flow upward or downward, the area of the flow cross section is continuously increased to balance the increase of on-way resistance in the flow direction, so that the refrigerant outlets 230 at both ends in the extension direction of the flat flow channel 211 may also distribute the refrigerant equal to the refrigerant outlets 230 near the refrigerant inlet 220.

Since the end cover portion 212 is simple in structure, the variable cross-section flat flow channel in the present embodiment is formed by the end cover portion 212, that is, the main body portion 213 is kept unchanged in structure, the shallow groove is equal in thickness a2, the end cover portion 212 is not hollowed at the center, the hollowed edge portion is a thickness a1-a2, and the hollowed edge portion is gradually inclined from the center to the edge, so that the variable cross-section flat flow channel 211 is formed after the end cover portion is matched with the main body portion 213, as shown in fig. 15 to 20 in particular, so that the increase of the structural complexity of the main body portion 213 can be avoided, and the processing and the assembly are convenient.

Thus, as shown in fig. 15 and 16, after assembly, the thickness of the thinnest part of the flat flow channel 211 is A2, the thickness of the widest part is A1, the total extension length of the flat flow channel 211 is h, and the inclination angles of the first sub-side 211A1 and the second sub-side 211A2 are equal and are both α, so that there is a relationship α =2 (A1-A2)/h, wherein the angle α is preferably 0.7 ° -2 °.

For further convenience of processing, in the present embodiment, both the axis of the refrigerant inlet 220 and the axis of the refrigerant outlet 230 are perpendicular to the thickness direction second side 211B, i.e., the thickness direction second side 211B is maintained as a vertical plane.

Further, referring to fig. 21 in conjunction with fig. 15, an arc-shaped recess 240 is formed in the thickness direction second side surface 211B at a position opposite to the refrigerant inlet 220. Specifically, the vertical cross-section of arc depressed part 240 is one section of a circle, the chord length is D, place radius of circle is R, the existence of this arc depressed part 240 makes the more even scattering of the fluid of high-speed incoming flow, simultaneously, sunken curved surface compares with the plane, the curved surface can carry out more effective buffering to the incoming flow under the same speed, be favorable to reducing loss of pressure, be favorable to making fluid shakeout rapidly simultaneously, the existence of camber makes the fluid turn tortuous flow in flat runner 211, as shown in fig. 21, be favorable to fluidic mixing more, further reduce the possibility that takes place gas-liquid phase separation.

In order to reduce the flow resistance caused by the vortex inside the flat tube 100, as shown in fig. 15, 16 and 21, the communication part between the refrigerant outlet 230 and the flat flow channel 211 is in a fillet transition, that is, a fillet is arranged on the inlet end of the refrigerant outlet 230, and the fillet radius r ranges from 0.5 mm to 2mm.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. An air conditioner comprises a multi-flat-tube parallel flow heat exchanger, wherein the multi-flat-tube parallel flow heat exchanger comprises an outer heat exchanger and an inner heat exchanger which are arranged along the air flow direction, the inner heat exchanger comprises a plurality of flat tubes, and the outer heat exchanger comprises a plurality of flat tubes which are in one-to-one correspondence with the flat tubes of the inner heat exchanger; the method is characterized in that:

the flat tubes are U-shaped and comprise upper horizontal sections, lower horizontal sections and bending parts for connecting the upper horizontal sections and the lower horizontal sections, the free ends of the upper horizontal sections are flat tube first ends, and the free ends of the lower horizontal sections are flat tube second ends;

the multi-flat-tube parallel flow heat exchanger further comprises:

the flow divider is used for distributing gas-liquid two-phase refrigerants into the flat tubes of the outer heat exchanger, and the first end of the flat tube of the outer heat exchanger is connected to the flow divider; the flow divider comprises a flow divider main body, a refrigerant inlet and a plurality of refrigerant outlets, wherein a flat flow channel is formed in the flow divider main body and extends along the arrangement direction of flat tubes of the outer heat exchanger; the refrigerant inlet is arranged on the flow divider main body and communicated with the flat flow channel on the first side surface of the flat flow channel in the thickness direction; the plurality of refrigerant outlets are used for being in one-to-one corresponding connection with the plurality of flat pipes of the outer row of heat exchangers, the refrigerant outlets are arranged on the flow divider main body and communicated with the flat flow channels on the second side face in the thickness direction of the flat flow channels, and the plurality of refrigerant outlets are distributed along the extension direction of the flat flow channels; along the extension direction of the flat flow channel, the first side surface in the thickness direction is composed of a first sub-side surface positioned on one side of the refrigerant inlet and a second sub-side surface positioned on the other side of the refrigerant inlet, and the first sub-side surface and the second sub-side surface are inclined towards the side where the refrigerant inlet is positioned;

2. The air conditioner according to claim 1,

the connector comprises a shell and a flat communication flow passage formed in the shell, the flat communication flow passage is provided with two inlet/outlet ports penetrating through the shell, one inlet/outlet port is communicated with the second end of the flat tube of the outer row of heat exchanger, and the other inlet/outlet port is communicated with the second end of the flat tube of the inner row of heat exchanger.

3. The air conditioner according to claim 2,

the section size of the flat communication flow passage is matched with the section size of the flat pipe.

4. The air conditioner according to claim 2,

and reinforcing ribs are arranged in the flat communicating flow passage.

5. The air conditioner according to claim 1,

the gas collecting pipe is a through pipe with two closed ends and communicated with the inside, and a connector correspondingly connected with the first end of the flat pipe of the inner row heat exchanger is arranged on the pipe body.

6. The air conditioner according to claim 1,

the multi-flat-tube parallel flow heat exchanger further comprises a main air tube assembly used for connecting the air collecting tube with the refrigerating system.

7. The air conditioner according to claim 6,

the main gas pipe assembly comprises a main gas pipe and a plurality of branch gas pipes communicated with the main gas pipe, the branch gas pipes are arranged along the extending direction of the main gas pipe and connected with the gas collecting pipe, one end of the main gas pipe is closed, and the other end of the main gas pipe is a connecting end used for being connected with a refrigerating system.

8. The air conditioner according to claim 1,

the number of the shunts is multiple, and each shunt corresponds to one part of flat tubes of the outer heat exchanger;

the multi-flat-tube parallel flow heat exchanger further comprises a liquid tube assembly used for connecting the shunt with a refrigeration system.

9. The air conditioner according to claim 8,

the liquid pipe subassembly including main liquid pipe, branch liquid head and with a plurality of branch liquid pipes that shunt quantity is the same, main liquid pipe one end be used for with refrigerating system throttle mechanism intercommunication, the other end with divide the flow head to connect, it is a plurality of the entrance point of branch liquid pipe is all connected divide overhead, it is a plurality of the exit end and a plurality of branch liquid pipe the shunt one-to-one is connected.