CN110207428A - Heat exchanger and heat pump system - Google Patents

Abstract

The invention discloses a heat exchanger and a heat pump system, and relates to the technical field of heat exchange equipment. The heat exchanger (300) comprises a single microchannel flat tube (100) and two headers (200) respectively arranged at the two ends of the length direction of the microchannel flat tube (100), the headers The outer peripheral wall of (200) is provided with the flat tube insertion interface (23) that is elongated along pipeline axial direction, and the two ends of described microchannel flat tube (100) extend through described flat tube insertion interface (23) respectively. into the lumen of the corresponding manifold (200). The heat exchanger (300) and the heat pump system of the present invention have good refrigerant circulation, uniform refrigerant distribution and high heat exchange efficiency, can realize non-stop defrosting, and improve user satisfaction.

Description

Heat Exchangers and Heat Pump Systems

technical field

The invention relates to the technical field of heat exchange equipment, in particular to a heat exchanger and a heat pump system.

Background technique

In the case of low temperature in winter, air conditioners are generally used for heating. The refrigerant in the outdoor heat exchanger of the air conditioner absorbs heat from the outdoor air. Since the temperature of the refrigerant in the outdoor heat exchanger is lower than that of the outdoor air, when the outdoor humidity is high, the surface of the outdoor heat exchanger will gradually Frosting, the heat transfer efficiency of the outdoor heat exchanger will be reduced after frosting, resulting in slow heating speed of the air conditioner, slow increase of indoor ambient temperature, poor air conditioner comfort, and poor user experience.

In order to ensure the stable heat supply of the air conditioner, it is necessary to defrost the outdoor heat exchanger. One of the existing defrosting methods is to switch from the heating cycle to the refrigeration cycle through the system, and the outdoor heat exchanger acts as a condenser to use its high-temperature refrigerant for defrosting; the other is to increase the opening of the expansion valve, Reduce its throttling effect, so that high-temperature refrigerant enters the outdoor heat exchanger for defrosting. However, when the air conditioner uses the above two methods for defrosting, the indoor unit of the air conditioner needs to be shut down to stop heating, which will cause the indoor temperature to drop and affect indoor comfort. And when the air conditioner switches to the refrigeration cycle for defrosting, the indoor heat exchanger will absorb heat from the room as an evaporator, so that the indoor temperature will further decrease when the defrosting is stopped, further affecting the comfort of the room. At the same time, when the air conditioning system switches between the heating cycle and the cooling cycle, it will increase the power consumption of the system, which is not conducive to energy saving and emission reduction.

Moreover, the header of the existing heat exchanger is correspondingly provided with a plurality of microchannel flat tubes, which is limited by the installation structure between the header and the microporous channel flat tubes, and the circulation and dispersion of the refrigerant are limited. Larger impact and the distribution of the refrigerant through the header to the flow of each micro-channel of each micro-channel flat tube is uneven, thus greatly affecting the heat exchange efficiency of the micro-channel heat exchanger.

Contents of the invention

Aiming at the above-mentioned defects and deficiencies of the prior art, the present invention provides a heat exchanger and heat pump system. The heat exchanger has good refrigerant circulation, uniform refrigerant distribution, and high heat exchange efficiency. It can realize non-stop defrosting and improve User satisfaction.

In order to achieve the above object, the present invention provides a heat exchanger, which includes a single microchannel flat tube and two headers respectively arranged at both ends of the microchannel flat tube in the length direction. The outer peripheral wall of the collecting pipe is provided with a strip-shaped flat tube insertion port extending along the pipeline axis direction, and the two ends of the microchannel flat tube are respectively inserted into the corresponding collecting pipe through the flat tube insertion port. in the lumen of the tube.

Optionally, the microchannel flat tube includes a lumen extending end, and the lumen extending end extends into the lumen along the radial direction of the collecting pipe toward the center of the collecting pipe, so that The radially protruding length of the protruding end of the lumen is smaller than the collecting tube radius R of the collecting tube and forms a radial distance k from the center of the collecting tube.

Optionally, the radial interval k satisfies: 0.5R≤k<R.

Further, the radial interval k may satisfy 5mm≤k≤25mm.

In addition, the length direction of the microchannel flat tube may be a horizontal direction, and the width direction of the microchannel flat tube may be the central axis direction of the header.

In addition, a closed welding seam surrounding the insertion port of the flat tube may be formed between the protruding end of the lumen and the outer peripheral wall of the collector.

Furthermore, the outer peripheral wall of the header may be provided with a pipe interface for the refrigerant to flow into or out of the lumen, and on the cross section of the header, the radial centerline of the pipe interface is in line with the The central angle between the radial centerlines of the flat tube sockets with respect to the center of the cross-section of the collector is θ, which satisfies: 90°≤θ≤270°.

Optionally, the central angle θ satisfies: 90°≤θ≤150° or 210°≤θ≤270°.

Wherein, the pipe interface is arranged in the middle of the collecting pipe in the axial direction, and the collecting pipe includes a sleeve adapter joint for connecting an external refrigerant pipe, and the sleeve adapter joint is fixed around the pipe interface Installed on the peripheral wall of the header.

In some embodiments, a refrigerant input hole is formed at the connecting end of the bushing adapter connected to the pipe interface, and the other end of the bushing adapter is formed as a pipe connection portion through which the refrigerant pipe is sheathed. , the inner diameter of the refrigerant pipeline is d ₃ , the inner diameter of the refrigerant input hole is d ₂ , the inner diameter of the pipe interface is d ₀ , and the outer diameter of the header is d ₄ , satisfying: _{20mm≤d4≤50mm} , _d4 > _d3 > _d2 > _d0 .

Further, the end of the hole where the refrigerant input hole is connected to the pipe interface is also formed with a flared cavity, the inner diameter of the flared cavity is d ₁ , and the inner diameter of d ₁ satisfies: d ₄ >d ₁ >d ₃ >d ₂ >d ₀ . Further, the outer end of the inner peripheral wall of the lumen of the sleeve adapter joint is formed with a welding chamfer slope, and the clamping between the welding chamfer slope and the end surface of the outer end of the sleeve adapter joint Angle β satisfies: 30°≤β≤80°.

Optionally, the heat exchanger further includes a heat-shrinkable sleeve for protecting the connection between the sleeve adapter joint and the refrigerant pipeline.

Furthermore, the heat exchanger may include a heating element extending along the length direction of the micro-channel flat tube and covering the surface of the micro-channel flat tube.

Additionally, the heating element may be a thick film heater.

In addition, the contact surface between the heating element and the microchannel flat tube may be provided with a heat-conducting silica gel layer.

Optionally, the microchannel flat tube includes multiple rows of microchannels arranged at intervals along the thickness direction, and the microchannels extend along the length direction of the microchannel flat tube.

Correspondingly, the present invention also provides a heat pump system, which includes an outdoor heat exchanger, an indoor heat exchanger, a compressor, and a four-way valve for switching between cooling and heating modes arranged on the refrigerant circuit. The heat pump system further includes the above-mentioned heat exchanger according to the present invention, the heat exchanger is arranged in series in the refrigerant pipeline between the outlet end of the compressor and the four-way valve;

Alternatively, the heat exchanger is arranged in series in the refrigerant refrigerant pipeline between the inlet end of the compressor and the four-way valve.

Optionally, the heat exchanger is arranged in series in the refrigerant pipeline between the outlet end of the compressor and the four-way valve, and the heat pump system further includes The oil separator in the refrigerant line between the four-way valves mentioned above.

Correspondingly, the present invention also provides another heat pump system, the heat pump system includes an outdoor heat exchanger, an indoor heat exchanger, a compressor, a plate exchange device and four cooling and heating modes for switching cooling and heating modes. The through valve is characterized in that the heat pump system further includes the above-mentioned heat exchanger, the plate exchange device is connected to the main flow of refrigerant between the outdoor heat exchanger and the indoor heat exchanger and the A refrigerant branch flow path leads out from the main flow path, and the refrigerant branch flow path exchanges heat with the refrigerant main flow path through the plate exchange device and returns to the compressor through the heat exchanger.

In the heat exchanger and heat pump system of the present invention, only a single micro-channel flat tube is arranged between two headers, and the refrigerant flows into the micro-channel flat tube through the header with good circulation and dispersion, and the refrigerant is distributed to the micro-channel The flow rate of each microchannel of the flat tube is uniform, thereby greatly improving the heat exchange efficiency of the microchannel flat tube.

Other features and advantages of the present invention will be described in detail in the detailed description that follows.

Description of drawings

Fig. 1 is a schematic structural view of a heat exchanger according to a specific embodiment of the present invention;

Fig. 2 is a partial sectional view of the heat exchanger of Fig. 1;

Fig. 3 is a partially enlarged view of part III of Fig. 2;

Figure 4 is an exploded view of the assembly of the heat exchanger of Figure 1;

Fig. 5 is the front view of the header in Fig. 4;

Fig. 6 is the structural representation of the microchannel flat tube in Fig. 4;

7 is a schematic diagram of a refrigerant branch circuit of a heat pump system according to an embodiment of the present invention;

8 is a schematic diagram of a refrigerant branch circuit of a heat pump system according to another embodiment of the present invention;

Fig. 9 is a schematic diagram of a refrigerant branch circuit of a heat pump system according to another embodiment of the present invention.

Explanation of reference signs

100 microchannel flat tube 1 microchannel

15 Flat tube body part 16 Lumen extension end

17 Mounting hole 200 Manifold

23 Flat tube socket 24 Pipe connection

25 Sleeve Adapter 26 Weld Chamfer Bevel

27 heat shrink tubing 300 heat exchanger

31 Heating element 311 Hole for welding structure

400 Outdoor heat exchanger 500 Compressor

600 Indoor heat exchanger 700 Four-way valve

800 board changing device

Detailed ways

Embodiments of the invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

The invention provides a heat exchanger and a heat pump system. The heat exchanger has good refrigerant circulation, uniform refrigerant distribution and high heat exchange efficiency, can realize non-stop defrosting, and improves user satisfaction.

As shown in FIGS. 1 and 5 , in a specific embodiment, the heat exchanger 300 includes a single microchannel flat tube 100 and two headers 200 arranged at both ends of the microchannel flat tube 100 in the length direction. The outer peripheral wall of the collecting pipe 200 is provided with a flat tube socket 23 extending in the direction of the pipe axis in a strip shape, and the two ends of the microchannel flat tube 100 extend into the corresponding collecting pipe 200 through the flat tube socket 23 respectively. in the lumen.

There are multiple micro-channel flat tubes between the two headers of the existing heat exchanger, so it is difficult to ensure that the refrigerant in the header is evenly distributed to each micro-channel, and it is limited by the difference between the header and the micro-channels. Due to the limitation of the installation structure between the flat tubes of the hole channel, the circulation and dispersion of the refrigerant are greatly affected, so the heat exchange efficiency of the existing heat exchanger is greatly limited. For this reason, the present invention provides a specific heat exchanger. The heat exchanger 300 only has a single microchannel flat tube between two headers. Good, good dispersibility, and the flow rate of the refrigerant distributed to each microchannel of the microchannel flat tube is uniform, thereby greatly improving the heat exchange efficiency of the microchannel flat tube.

Optionally, the microchannel flat tube 100 includes a lumen extending end 16, and the lumen extending end 16 extends into the lumen along the radial direction of the collecting tube 200 toward the center of the collecting tube 200, and the lumen extending end 16 The radial protruding length of is smaller than the radius of the header 200 and forms a radial distance k from the center of the header 200 .

As shown in FIG. 6 , the microchannel flat tube 100 includes a flat tube main body 15 and a lumen extending end 16 , and the lumen extending end 16 can be processed by milling both ends of the flat tube main body 15 . As shown in FIG. 2 and FIG. 3 , the lumen-introducing end 16 extends into the lumen through the flat tube insertion port 23 along the radial direction of the header 200 toward the center of the header 200 . When the end 16 of the lumen extends into the lumen of the header 200 through the flat tube insertion port 23, if the length of the end 16 of the lumen is too long, it will reduce the flow of refrigerant from the header 200 into the micro cavity. The fluidity of the microchannel 1 of the channel flat tube 100 ; if the length of the lumen extension end 16 is too short, it is not conducive to the assembly reliability between the header 200 and the microchannel flat tube 100 . For this reason, the radially protruding length of the lumen protruding end 16 can be set to be smaller than the collecting tube radius R of the collecting tube 200 .

Furthermore, when the radial interval k is larger, it is more conducive to the dispersion of the refrigerant in the header 200, so that the refrigerant can enter each microchannel 1 more uniformly, so the radial interval k can satisfy: 0.5R≤k< R, specifically, can satisfy: 5mm≤k≤25mm, thereby not only making the flow rate of the refrigerant in each microchannel 1 relatively uniform, but also ensuring the assembly reliability between the header 200 and the microchannel flat tube 100, and at the same time It can also greatly improve the circulation of the refrigerant flowing from the header 200 into the microchannel 1 of the microchannel flat tube 100 .

Further, the length direction of the micro-channel flat tube 100 can be a horizontal direction, and the width direction of the micro-channel flat tube 100 can be the central axis direction of the header 200, so that the refrigerant can be more evenly distributed to each micro-hole channel 1.

In addition, a closed welding seam around the flat tube insertion port 23 may be formed between the lumen extending end 16 and the outer peripheral wall of the collector tube 200 . This not only ensures the assembly reliability between the header 200 and the microchannel flat tube 100, but also seals the heat exchanger to prevent leakage of refrigerant.

Optionally, as shown in FIGS. 3 and 4 , the outer peripheral wall of the header 200 is provided with a pipe interface 24 for the refrigerant to flow into or out of the lumen. On the cross section of the header 200 , the radial direction of the pipe interface 24 The central angle between the central line and the radial central line of the flat tube socket 23 with respect to the center of the cross section of the header 200 is θ. Specifically, referring to FIG. 3 , as the name implies, the radial centerline of the pipeline interface 24 is the radial line passing through the center of the cross-section of the header 200 and the radial line is the centerline passing through the center of the pipeline interface 24. In other words, the pipeline The radial centerline of the interface 24 is the connecting line passing through the center of the cross-section of the header 200 and the center of the pipeline interface 24; The centerline of the flat tube insertion port 23. When θ is less than 90° or 270°, the circulation of the refrigerant between the header 200 and the microchannel flat tube 100 is relatively general; when θ is 180°, the refrigerant flows directly from the header 200 to the microchannel flat tube 100 , the pressure of the system is relatively high, so θ can be set to satisfy: 90°≤θ≤270°.

In order to further improve the circulation of the refrigerant between the header 200 and the microchannel flat tube 100 while simultaneously reducing the system pressure, θ can be set to satisfy: 90°≤θ≤150° or 210°≤θ≤270°.

In a specific embodiment, in order to ensure uniform distribution of the refrigerant between the header 200 and the microchannel flat tube 100 , the pipe interface 24 is arranged in the middle of the header 200 along the axial direction of the header 200 . The header 200 may include a bushing adapter 25 for connecting an external refrigerant pipe, and the bushing adapter 25 is fixedly installed on the peripheral wall of the header 200 around the pipe interface 24 . Specifically, as shown in FIG. 3 , in order to ensure the circulation and dispersion uniformity of the refrigerant between the header 200 and the microchannel flat tube 100 . The connecting end of the sleeve adapter 25 connected to the pipe interface 24 is formed with a refrigerant input hole, and the other end of the sleeve adapter 25 is formed as a pipe connection portion through which a refrigerant pipeline is sheathed. The inner diameter of the refrigerant pipeline is d ₃ , The inner diameter of the refrigerant input hole is d ₂ , the inner diameter of the pipe interface 24 is d ₀ , and the outer diameter of the header 200 is d ₄ , satisfying: 20mm≤d ₄ ≤50mm, d ₄ >d ₃ >d ₂ >d ₀ . Wherein, the bushing adapter 25 is arranged coaxially with the pipeline interface 24 and the axial direction of the pipeline interface 24 is perpendicular to the axial direction of the header 200 . At the same time, a limit step for installing the refrigerant pipeline is formed between the pipe connection part of the casing adapter 25 and the refrigerant input hole, so the inner diameter of the refrigerant input hole is set to _d3 greater than the inner diameter of the refrigerant pipeline is d ₂ .

Further, the end of the hole where the refrigerant input hole is connected to the pipeline interface 24 is also formed with a flared cavity. In order to allow the casing adapter 25 to be better welded to the pipeline interface 24, the inner diameter of the flared cavity is set to be larger _than the refrigerant input. The inner diameter of the hole is d ₂ , and the inner diameter of the flared cavity is d ₁ , satisfying: d ₄ >d ₁ >d ₃ >d ₂ >d _0, .

In addition, the outer end of the inner peripheral wall of the lumen of the sleeve adapter 25 may be formed with a welding chamfer slope 26, and the angle β between the welding chamfer slope 26 and the end surface of the outer end of the sleeve adapter 25 Satisfy: 30°≤β≤80°. In this way, the welding between the casing adapter joint 25 and the refrigerant pipeline can be made more firmly, and the sealing performance of the welding is better. Wherein, the outer end of the inner peripheral wall of the lumen of the sleeve adapter 25 is the end away from the header 200 .

In addition, in order to protect the welding part between the sleeve adapter joint 25 and the refrigerant pipeline, a heat-shrinkable sleeve 27 can be added on the welding part. At the same time, in order to ensure the welding quality, boiler brazing can be used for welding and fixing, and the collecting pipe 200 and the microchannel flat tube 100 can also be made of 3003 aluminum material with excellent welding performance.

In addition, as shown in FIG. 4 , the heat exchanger 300 may include a heating element 31 extending along the length direction of the microchannel flat tube 100 and covering the surface of the microchannel flat tube 100 . Wherein, the top wall of the microchannel flat tube 100 can also be provided with a mounting structure hole 17, which is used to fit and install with the welding structure hole 311 of the heating element 31, so that heating elements can be installed on the microchannel flat tube 100 31, thereby heating the microchannel flat tube 100, increasing the overall energy of the system to achieve the purpose of non-stop defrosting of the outdoor heat exchanger.

Optionally, the heating element 31 can be a thick film heating body, and of course other heating devices such as heating resistors can also be added.

In addition, the contact surface between the heating element 31 and the microchannel flat tube 100 can be provided with a heat-conducting silicone layer, so that the heat transfer on the contact surface between the heating element 31 and the microchannel flat tube 100 is more uniform and the heat exchange rate is higher.

Further, as shown in FIG. 6 , the microchannel flat tube 100 may include multiple rows of microchannels 1 arranged at intervals along the thickness direction, and the microchannels 1 extend along the length direction of the microchannel flat tube 100 . Conventional microchannel flat tubes have one and only one line of microchannels 1 along the thickness direction of the flat tube cross section, while the main heat exchange element of the microchannel flat tube heat exchanger is the microchannel flat tube, so the heat transfer of the microchannel flat tube is improved. The efficiency can improve the heat transfer efficiency of the microchannel heat exchanger. There are two main methods to improve the heat exchange efficiency of microchannel heat exchangers. One is to increase the size of the heat exchanger, but since the size of the heat exchanger is limited by the installation space, the space for increasing the size is small; The other is to improve the internal heat transfer efficiency of the microchannel flat tube by optimizing the internal structural parameters of the microchannel flat tube.

The heat exchanger 300 of the present invention greatly increases the internal heat exchange area by arranging multiple rows of microchannels 1 along the thickness direction of the flat tube cross section, and the heat exchange efficiency is high, so that the defrosting of the heat pump system during the heating cycle in winter The speed is increased, and there is no need to stop the machine for defrosting, so as to ensure the stable operation of the indoor heat exchanger 600, thereby providing users with a comfortable and stable indoor temperature, and greatly improving customer satisfaction. At the same time, the microchannel flat tube 100 can disperse the internal pressure of the system and reduce the pressure drop, so as to ensure that the heat exchanger has sufficient pressure bearing capacity, making the whole system safe and reliable.

Correspondingly, as shown in Fig. 7, the present invention also provides a heat pump system, which includes an outdoor heat exchanger 400, an indoor heat exchanger 600, a compressor 500 and For the four-way valve 700 in thermal mode, the heat pump system further includes the above-mentioned heat exchanger 300 according to the present invention, and the heat exchanger 300 is arranged in series in the refrigerant pipeline between the outlet end of the compressor 500 and the four-way valve 700; or, The heat exchanger 300 is arranged in series in the refrigerant pipeline between the inlet port of the compressor 500 and the four-way valve 700 .

In the low temperature weather in winter, when the air energy heat pump unit is used for heating operation, the conventional heat pump system needs to be shut down periodically to defrost, the indoor temperature drops and the energy consumption increases during the defrost process, so the present invention provides a specific A low-temperature strong-heat heat pump system that can defrost without shutting down. The above-mentioned heat exchanger 300 is installed in the refrigerant pipeline between the outlet end of the compressor 500 and the four-way valve 700. The heat exchanger 300 is used for exchanging heat outdoors. The device 400 defrosts to achieve the purpose of non-stop defrosting. Since the heat exchanger 300 has a large internal heat exchange area and high heat exchange efficiency, rapid heating and defrosting can be realized and the heat pump system can continue to heat, so that users can quickly feel comfortable.

Specifically, as shown in FIG. 7 , in a thermal cycle of a heat pump system, when the four-way valve 700 is switched to the heating mode, the high-temperature and high-pressure refrigerant comes out from the outlet port of the compressor 500 and passes through the heat exchange successively. 300 and four-way valve 700 (along the solid line path inside the four-way valve 700 shown in FIG. 7 ) flows to the indoor heat exchanger 600, electronic expansion valve, outdoor heat exchanger 400, etc. and returns to the compressor 500, and the system is completed. Refrigerant circulation loop in heat mode. In addition, the heat pump system may further include an oil separator arranged in series in the refrigerant pipeline between the heat exchanger 300 and the four-way valve 700 . When the air conditioner is in the heating mode, the refrigerant coming out of the outlet of the compressor 500 will bring out the oil of the compressor 500. At this time, the heat exchanger 300 can heat the refrigerant coming out of the outlet of the compressor 500, thereby The refrigerant and the engine oil mixed in the refrigerant can be quickly separated, so that the compressor 500 can run quickly and reliably to improve the heating efficiency of the heat pump system.

Or, specifically, in another thermal cycle of the heat pump system, as shown in FIG. 8 , when the four-way valve 700 is switched to the heating mode, the high-temperature and high-pressure refrigerant comes out from the outlet port of the compressor 500 and flows sequentially. After passing through the four-way valve 700 (along the solid line path in the four-way valve 700 shown in FIG. 8 ), the indoor heat exchanger 600, the electronic expansion valve, the outdoor heat exchanger 400, the four-way valve 700 and the heat exchanger 300 Back to compressor 500. Likewise, the heat pump system may further include an oil separator arranged in series in the refrigerant pipeline between the compressor 500 and the four-way valve 700 .

Wherein, when the surface temperature of the outdoor heat exchanger 400 is low, it may cause frost on the surface of the outdoor heat exchanger 400. Therefore, in the above two heat pump systems, the heating element 31 is used to heat the heat exchanger 300 to improve the efficiency of the heat pump. The overall energy of the system can achieve the purpose of defrosting the outdoor heat exchanger 400 without shutting down, which can make the system run continuously without shutting down. When the four-way valve 700 is switched to the cooling mode, there is no frosting on the surface of the outdoor heat exchanger 400 and no defrosting is required.

Correspondingly, as shown in FIG. 9 , the present invention also provides another heat pump system, which includes an outdoor heat exchanger 400 , an indoor heat exchanger 600 , a compressor 500 , and a plate exchange device 800 arranged on the refrigerant circuit. and a four-way valve 700 for switching cooling and heating modes, the heat pump system also includes the above-mentioned heat exchanger 300, a plate exchange device 800 is connected to the main flow of refrigerant between the outdoor heat exchanger 400 and the indoor heat exchanger 600, and A refrigerant branch flow is led out from the main flow path, and the refrigerant branch flow passes through the plate exchange device 800 to exchange heat with the refrigerant main flow path, and then returns to the compressor 500 through the heat exchanger 300 .

As shown in Figure 9, in the thermal cycle of the air conditioning system, when switching to the heating mode through the four-way valve 700, the high-temperature and high-pressure refrigerant comes out from the outlet of the compressor 500 and passes through the gas-liquid separator and the four-way valve 700 It reaches the indoor heat exchanger 600 for heat release, and then returns to the compressor 500 through the plate exchange device 800 of the refrigerant main flow, the outdoor heat exchanger 400 and the four-way valve 700 in sequence. By drawing part of the refrigerant from the main refrigerant flow path into the branch refrigerant flow path, the branch refrigerant flow path of the refrigerant branch flow path is throttled and depressurized by the electronic expansion valve, and then enters the plate replacement device 800 and absorbs the heat of the refrigerant in the main refrigerant flow path in the plate change device 800 After evaporation, it returns to the compressor 500 through the heat exchanger 300. Among them, the refrigerant in the main refrigerant flow path enters the outdoor heat exchanger 400 to absorb external heat after being cooled by the refrigerant in the refrigerant branch flow path, and then returns to the compressor 500 through the four-way valve 700, thereby increasing the circulation of the main refrigerant flow path The enthalpy difference of the loop greatly increases the efficiency of the compressor 500 . Similarly, the heating element 31 heats the heat exchanger 300 to increase the overall energy of the heat pump system to achieve the purpose of defrosting the outdoor heat exchanger 400 without stopping the machine.

In the heat exchanger and heat pump system of the present invention, only a single micro-channel flat tube is arranged between two headers, and the refrigerant has good circulation when flowing into the micro-channel flat tube through the header, and the refrigerant is distributed to each of the micro-channel flat tubes. The flow rate of the microchannel is uniform, thereby greatly improving the heat exchange efficiency of the microchannel flat tube. And by optimizing the installation structural parameters between the header 200 and the microchannel flat tube 100, the circulation and uniformity of the refrigerant between the header 200 and the microchannel flat tube 100 are better, so that the heat exchanger 300 The heat exchange efficiency is higher. At the same time, by adding heating elements 31 to the heat exchanger 300, the overall energy of the heat pump system can be increased to achieve the purpose of defrosting the outdoor heat exchanger 400 without stopping the machine, so that the heat pump system can continue to heat, and users can quickly experience comfortable effect. At the same time, the heat pump system of the present invention can realize rapid start-up of heating.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, including combining each specific technical feature in any suitable manner. Not otherwise stated. However, these simple modifications and combinations should also be regarded as the content disclosed by the present invention, and all belong to the protection scope of the present invention.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial", The orientation or positional relationship indicated by "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or element Must be in a particular orientation, be constructed in a particular orientation, and operate in a particular orientation, and therefore should not be construed as limiting the invention.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; can be mechanically connected, can also be electrically connected or can communicate with each other; can be directly connected, can also be indirectly connected through an intermediary, can be the internal communication of two components or the interaction relationship between two components, unless expressly defined otherwise. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the present invention, unless otherwise clearly specified and limited, the first feature may be in direct contact with the first feature or the first and second feature may be in direct contact with the second feature through an intermediary. touch. Moreover, "above", "above" and "above" the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "beneath" and "beneath" the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

Although the embodiment of the present invention has been shown and described above, it can be understood that the above embodiment is exemplary and should not be construed as a limitation of the present invention, and those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (20)

1. a heat exchanger, it is characterized in that, described heat exchanger (300) comprises single microchannel flat tube (100) and two ends that are respectively arranged in the length direction of described microchannel flat tube (100) A collecting pipe (200), the peripheral wall of the collecting pipe (200) is provided with a flat pipe insertion port (23) extending in a strip shape along the pipeline axis direction, and two of the microchannel flat pipes (100) The ends respectively extend into the lumen of the corresponding collector (200) through the flat tube insertion port (23). 2. The heat exchanger according to claim 1, characterized in that, the microchannel flat tube (100) includes a lumen extending end (16), and the lumen extending end (16) extends along the collector. The flow pipe (200) radially extends into the lumen toward the center of the collecting pipe (200), and the radially extending length of the lumen-introducing end (16) is less than the length of the collecting pipe ( 200) of the header radius R and form a radial distance k from the center of said header (200). 3 . The heat exchanger according to claim 2 , wherein the radial interval k satisfies: 0.5R≦k<R. 4. The heat exchanger according to claim 2, wherein the radial interval k satisfies: 5mm≤k≤25mm. 5. The heat exchanger according to claim 2, characterized in that, the length direction of the microchannel flat tube (100) is a horizontal transverse direction, and the width direction of the microchannel flat tube (100) is the The direction of the central axis of the flow tube (200). 6. The heat exchanger according to claim 2, characterized in that, a socket around the flat tube is formed between the lumen extending end (16) and the outer peripheral wall of the header (200). (23) closed weld. 7. The heat exchanger according to claim 2, characterized in that, the outer peripheral wall of the header (200) is provided with a pipe interface (24) for the refrigerant to flow into or out of the lumen, and in the header On the cross-section of the flow tube (200), the transverse direction between the radial centerline of the pipe interface (24) and the radial centerline of the flat tube insertion port (23) with respect to the header (200) The central angle of the section center is θ, which satisfies: 90°≤θ≤270°. 8. The heat exchanger according to claim 6, wherein the central angle θ satisfies: 90°≤θ≤150° or 210°≤θ≤270°. 9. The heat exchanger according to claim 7, characterized in that, the pipe interface (24) is arranged in the middle of the axial direction of the header (200), and the header (200) includes a A sleeve adapter (25) connected to an external refrigerant pipe, the sleeve adapter (25) is fixedly installed on the outer peripheral wall of the collector (200) around the pipe interface (24). 10. The heat exchanger according to claim 9, characterized in that a refrigerant input hole is formed at the connecting end of the sleeve adapter (25) connected to the pipe interface (24), and the sleeve The other end of the adapter joint (25) is formed as a pipe connection portion through which a refrigerant pipe is sheathed. The inner diameter of the refrigerant pipe is d ₃ , the inner diameter of the refrigerant input hole is d ₂ , and the pipe interface The inner diameter of (24) is d ₀ , and the outer diameter of the collector (200) is d ₄ , satisfying: 20mm≤d ₄ ≤50mm, d ₄ >d ₃ >d ₂ >d ₀ . 11. The heat exchanger according to claim 10, characterized in that, the end of the hole where the refrigerant input hole is connected to the pipe interface (24) is also formed with a flared cavity, and the inner diameter of the flared cavity is d ₁ , the inner diameter being d ₁ satisfies: d ₄ >d ₁ >d ₃ >d ₂ >d ₀ . 12. The heat exchanger according to claim 9, characterized in that, the outer end of the inner peripheral wall of the tube lumen of the casing adapter (25) is formed with a welding chamfer slope (26), and the welding chamfer The included angle β between the angled inclined surface (26) and the end surface of the outer end of the bushing adapter (25) satisfies: 30°≤β≤80°. 13. The heat exchanger according to claim 9, characterized in that, the heat exchanger (300) further includes a heat exchanger for protecting the connection between the sleeve adapter (25) and the refrigerant pipeline. Shrink sleeve (27). 14. The heat exchanger according to claim 1, characterized in that, the heat exchanger (300) includes extending along the length direction of the microchannel flat tube (100) and covering the microchannel flat tube ( 100) surface heating element (31). 15. The heat exchanger according to claim 14, characterized in that, the heating element (31) is a thick film heating body. 16. The heat exchanger according to claim 14, characterized in that, the contact surface between the heating element (31) and the microchannel flat tube (100) is provided with a heat-conducting silica gel layer. 17. The heat exchanger according to any one of claims 1 to 16, characterized in that, the microchannel flat tube (100) comprises multiple rows of microchannels (1) arranged at intervals along the thickness direction, the The microchannel (1) extends along the length direction of the microchannel flat tube (100). 18. A heat pump system, comprising an outdoor heat exchanger (400), an indoor heat exchanger (600), a compressor (500) and a four-way valve (700) for switching cooling and heating modes arranged on the refrigerant circuit , characterized in that the heat pump system further comprises the heat exchanger (300) according to any one of claims 1-17, the heat exchanger (300) is arranged in series at the compressor (500) In the refrigerant refrigerant pipeline between the outlet end and the four-way valve (700); Alternatively, the heat exchanger (300) is arranged in series in the refrigerant refrigerant pipeline between the inlet port of the compressor (500) and the four-way valve (700). 19. The heat pump system according to claim 18, characterized in that, the heat exchanger (300) is arranged in series between the outlet end of the compressor (500) and the refrigerant of the four-way valve (700). In the refrigerant pipeline, the heat pump system further includes an oil separator arranged in series in the refrigerant pipeline between the heat exchanger (300) and the four-way valve (700). 20. A heat pump system, comprising an outdoor heat exchanger (400), an indoor heat exchanger (600), a compressor (500), a plate exchange device (800) and a cooling and heating mode switch set on the refrigerant circuit The four-way valve (700), characterized in that the heat pump system further includes the heat exchanger (300) according to any one of claims 1-17, the outdoor heat exchanger (400) and the The main refrigerant flow path between the indoor heat exchangers (600) is connected with the plate exchange device (800) and a refrigerant branch flow path is drawn from the main flow path, and the refrigerant branch flow path passes through the plate exchange device (800) and The refrigerant main flow returns to the compressor (500) through the heat exchanger (300) after heat exchange.