Heat exchange structure, air conditioner and defrosting control method of air conditioner outdoor unit

Abstract

This invention provides a heat exchange structure, an air conditioner, and a defrosting control method for the outdoor unit of an air conditioner. The heat exchange structure includes: a heat exchange pipe comprising a first pipe, a second pipe, and a third pipe connected in series, wherein the second pipe is located between the first pipe and the third pipe, the inner diameter of the second pipe is smaller than that of the first pipe, and the inner diameter of the second pipe is smaller than that of the third pipe; an air inlet is formed on the side of the first pipe away from the second pipe, and an air outlet is formed on the side of the third pipe away from the second pipe; a heat exchanger disposed in the second pipe; and a fan disposed on the side of the heat exchange pipe near the air inlet and the side of the heat exchange pipe near the air outlet. This invention solves the problems of increased costs due to the need to increase raw materials when improving the heat exchange capacity of the outdoor unit heat exchanger, and the inability of the indoor unit to continue heating during defrosting of the outdoor unit heat exchanger.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and more specifically, to a heat exchange structure, an air conditioner, and a defrosting control method for the outdoor unit of an air conditioner. Background Technology

[0002] Currently, the most common heat exchange method for air conditioner outdoor unit heat exchangers is air-cooled heat exchange, and the main material of the heat exchanger is copper tubes, which are relatively expensive. In order to achieve sufficient heat exchange, residential outdoor units usually increase the size of the heat exchanger to increase the heat exchange area. Although the heat exchange area is larger, the amount of copper tubes and aluminum foil used increases, leading to higher costs.

[0003] Meanwhile, for heat pump units, the problem of frost formation on the outdoor unit's heat exchanger under low-temperature conditions is difficult to solve. The commonly used defrosting method is to use a four-way valve to switch directions, using high-temperature refrigerant to flow through the outdoor unit's heat exchanger for defrosting. At this time, the indoor unit stops heat exchange and cannot continue heating. Summary of the Invention

[0004] The problem solved by this invention is that increasing the heat exchange capacity of the outdoor unit heat exchanger requires additional raw materials, which increases costs, and the indoor unit cannot continue heating when the outdoor unit heat exchanger defrosts.

[0005] To address the aforementioned problems, this invention provides a heat exchange structure, an air conditioner, and a defrosting control method for the outdoor unit of an air conditioner.

[0006] On one hand, the present invention provides a heat exchange structure, comprising: a heat exchange pipe, the heat exchange pipe including a first pipe, a second pipe and a third pipe connected in series, wherein the second pipe is located between the first pipe and the third pipe, the inner diameter of the second pipe is smaller than that of the first pipe and the inner diameter of the third pipe is smaller than that of the third pipe, an air inlet is formed on the side of the first pipe away from the second pipe, and an air outlet is formed on the side of the third pipe away from the second pipe; a heat exchanger disposed in the second pipe; and a fan disposed on the side of the heat exchange pipe near the air inlet and the side of the heat exchange pipe near the air outlet.

[0007] Compared with existing technologies, the technical effects achieved by this solution are as follows: The heat exchanger is placed in the second pipeline, that is, at the position where the inner diameter of the heat exchange pipe is smallest; air enters from the air inlet, and as the cross-sectional area of ​​the inner cavity of the heat exchange pipe decreases, the wind speed increases. The point where the cross-sectional area of ​​the inner cavity of the heat exchange pipe is smallest is the point where the wind speed is largest. At this point, the heat transfer coefficient of the heat exchanger is largest. According to the heat transfer formula, the heat transfer coefficient φ=Ak When the temperature difference Δt is constant, as the heat transfer coefficient k increases, the heat transfer area A can be reduced for the same amount of heat transfer, i.e., the size of the heat exchanger can be reduced, thereby reducing the amount of raw materials used and the cost. The high-speed air at the second pipeline can blow away the newly formed frost, thus slowing down the frost formation. If frost has already formed on the windward side of the heat exchanger, all the fans are controlled to reverse, and the windward side of the heat exchanger is converted to the leeward side, further removing the accumulated frost layer.

[0008] Furthermore, the heat exchange structure also includes a drive unit and a transmission shaft, the transmission shaft connecting the drive unit and all the fans.

[0009] The technical effects achieved by adopting this technical solution are as follows: the driving component controls the rotation of all the fans simultaneously, which facilitates the simultaneous control of all the fans to reverse and perform defrosting. At the same time, it reduces the number of driving components and saves space occupied by the heat exchange structure.

[0010] Furthermore, the drive shaft includes a first drive shaft and a second drive shaft, and the drive member connects the first drive shaft and the second drive shaft; the fan includes a first fan disposed at the air inlet and a second fan disposed at the air outlet, the first drive shaft connects to the first fan, and the second drive shaft connects to the second fan.

[0011] The technical effect achieved by adopting this technical solution is that the driving component makes full use of the gap between the first fan and the second fan, and avoids the driving component occupying the space outside the heat exchange structure.

[0012] Furthermore, the first fan includes a first connector and a first fan blade surrounding the first connector, and the second fan includes a second connector and a second fan blade surrounding the second connector; wherein both the first fan blade and the second fan blade are bent toward the air inlet.

[0013] The technical effects achieved by adopting this technical solution are as follows: the first fan and the second fan rotate in the same direction, so that the airflow can flow evenly in the first pipe and the third pipe, further improving the heat exchange effect. At the same time, during defrosting, it is convenient to quickly discharge the blown-out frost from the heat exchange pipe.

[0014] Furthermore, the heat exchanger includes a shaft hole located at the center of the second pipeline, through which the first drive shaft passes, and the drive element is located on the side of the heat exchanger facing the second fan.

[0015] The technical effects achieved by adopting this technical solution are as follows: the second fan blade faces the heat exchanger, that is, the second connector is close to the air outlet. At this time, the distance between the second connector and the heat exchanger is greater than the distance between the first connector and the heat exchanger, and there is a larger space between the second connector and the heat exchanger to accommodate the driving component. At the same time, the driving component is located on one side of the heat exchanger and is not connected to the heat exchanger, which can avoid the driving component occupying the heat exchange area of ​​the heat exchanger and thus reducing the heat exchange effect.

[0016] Furthermore, the heat exchange structure also includes: a first air guide duct, which connects the first pipeline and the second pipeline, the diameter of the first air guide duct gradually decreases along the direction from the first pipeline to the second pipeline, and the side of the first air guide duct facing the air inlet forms a windward surface.

[0017] The technical effects achieved by adopting this technical solution are as follows: the windward side of the first air duct can guide the air to the middle of the second duct, and at the same time facilitate the introduction of the blown frost into the second duct, avoiding the accumulation of frost between the first duct and the second duct.

[0018] Furthermore, the heat exchange structure also includes a second air duct, which connects the second pipeline and the third pipeline. The diameter of the second air duct gradually increases along the direction of the second pipeline and the third pipeline, and the side of the second air duct facing the air outlet forms a leeward side.

[0019] The technical effects achieved by adopting this technical solution are as follows: the second air duct facilitates the rapid discharge of the air after heat exchange, and at the same time, facilitates the discharge of the blown-out frost; when the drive component reverses, the fan reverses, and the functions of the first air duct and the second air duct are interchanged.

[0020] Furthermore, the heat exchange structure also includes a grille, which is disposed at the air inlet and the air outlet.

[0021] The technical effect achieved by adopting this technical solution is that when any one of the grilles is used as an air inlet, foreign objects can be prevented from entering the heat exchange pipeline, ensuring the normal operation of the fan, the heat exchanger and the drive component.

[0022] On the other hand, the present invention also provides an air conditioner including the heat exchange structure provided in any of the above embodiments.

[0023] The technical effects achieved by adopting this technical solution are as follows: the air conditioner can improve the heat exchange effect of the heat exchanger and save costs through the heat exchange structure; at the same time, defrosting can be achieved by controlling the rotation of the fan. In the defrosting mode of the air conditioner, the indoor heating does not need to be stopped, so as to avoid affecting the user's comfort.

[0024] In another aspect, the present invention also provides a defrosting control method for an air conditioner outdoor unit, implemented through the heat exchange structure provided in any of the above embodiments. The defrosting control method for the air conditioner outdoor unit includes: the air conditioner activating the defrosting mode; determining whether frost has formed on the side of the heat exchange pipe near the air inlet; if not, all the fans continuously blow air towards the air outlet; if so, all the fans continuously blow air towards the air inlet, and the air inlet and the air outlet are interchanged.

[0025] The technical effects achieved by adopting this technical solution are as follows: the air conditioner reduces its inner diameter through the second pipe, thereby improving the heat exchange effect; when the heat exchange pipe is not frosted, the fan keeps running at high speed, causing the heat exchanger to heat up rapidly, reducing frost accumulation, and quickly dissipating the blown-out frost; since frost mainly occurs on the windward side, the fan direction is switched to change the windward side to the leeward side, thereby quickly removing the frost on the windward side; after the windward and leeward sides are interchanged, if frost occurs on the new windward side, it can also be defrosted in time, thereby continuously achieving the defrost-removing effect.

[0026] In summary, the above embodiments of this application can have one or more of the following advantages or beneficial effects: i) The inner diameter of the second pipe is smaller than that of the first and third pipes on both sides, so the airflow velocity is greater when it flows through the second pipe, resulting in better heat exchange. Placing the heat exchanger in the second pipe can effectively improve the heat exchange effect and prevent the heat exchanger from frosting; ii) The motor reverses, controlling the first and second fans to reverse, at which time the windward side of the heat exchanger becomes the leeward side, and the windward surface of the first air guide becomes the leeward surface, thereby effectively removing all frost formed at the windward position and preventing the frost at the windward position from continuing to accumulate. At the same time, the blown-out frost is quickly discharged. When frost begins to accumulate on the other side, the motor reverses again, so that all parts of the heat exchange pipe can be effectively defrosted; iii) The defrosting process does not affect the heating process of the indoor unit, avoiding affecting the user experience. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a heat exchange structure provided in the first embodiment of the present invention.

[0028] Figure 2 This is a cross-sectional view of the heat exchange structure.

[0029] Figure 3 This is a flowchart of a defrosting control method for an air conditioner outdoor unit provided in the third embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 100-Heat exchange structure; 110-Heat exchange pipe; 111-First pipe; 112-Second pipe; 113-Third pipe; 114-Air inlet; 115-Air outlet; 116-First air duct; 117-Second air duct; 120-Heat exchanger; 121-Shaft hole; 131-First fan; 131a-First connector; 131b-First fan blade; 132-Second fan; 132a-Second connector; 132b-Second fan blade; 140-Drive component; 151-First drive shaft; 152-Second drive shaft; 160-Grate. Detailed Implementation

[0032] The purpose of this invention is to provide a heat exchange structure that can improve heat exchange while saving costs, and does not affect the heating mode of the indoor unit during defrosting.

[0033] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0034] [First Embodiment]

[0035] On the one hand, see Figure 1-2 The first embodiment of the present invention provides a heat exchange structure 100, which includes, for example, a heat exchange pipe 110, a heat exchanger 120, and a fan. The heat exchange pipe 110 includes a first pipe 111, a second pipe 112, and a third pipe 113 that are connected. The second pipe 112 is located between the first pipe 111 and the third pipe 113. The inner diameter of the second pipe 112 is smaller than that of the first pipe 111, and the inner diameter of the second pipe 112 is smaller than that of the third pipe 113. An air inlet 114 is formed on the side of the first pipe 111 away from the second pipe 112, and an air outlet 115 is formed on the side of the third pipe 113 away from the second pipe 112. The heat exchanger 120 is disposed on the second pipe 112. The fan is disposed on the side of the heat exchange pipe 110 near the air inlet 114 and the side of the heat exchange pipe 110 near the air outlet 115.

[0036] In this embodiment, the heat exchanger 120 is placed in the second pipe 112, that is, at the position where the inner diameter of the heat exchange pipe 110 is the smallest. Air enters from the air inlet 114. As the cross-sectional area of ​​the inner cavity of the heat exchange pipe 110 decreases, the air velocity increases. The point where the cross-sectional area of ​​the inner cavity of the heat exchange pipe 110 is the smallest is the point where the air velocity is the largest. At this point, the heat transfer coefficient of the heat exchanger 120 is the largest. According to the heat transfer formula, the heat transfer coefficient φ = Ak When the temperature difference Δt is constant, as the heat transfer coefficient k increases, the heat transfer area A can be reduced for the same amount of heat transfer, that is, the size of the heat exchanger 120 can be reduced, thereby achieving the effect of reducing the amount of raw materials used and the cost.

[0037] It should be noted that the temperature on the windward side of heat exchanger 120 is lower than that on the leeward side. Water vapor in the air easily condenses into frost on the windward side. By the time the air reaches the leeward side of heat exchanger 120, the water vapor content in the air has decreased, making frost formation less likely. Therefore, if frost has already begun to form on the windward side of heat exchanger 120, all fans are reversed, turning the windward side of heat exchanger 120 into the leeward side, which removes the accumulated frost layer. The high-speed airflow at the second pipe 112 can also disperse the newly formed frost, thus slowing down the frost formation process.

[0038] Preferably, the inner diameters of the first pipe 111 and the third pipe 113 are the same, and the openings of the air inlet 114 and the air outlet 115 are the same, so that when the fan reverses, the first pipe 111 and the third pipe 113 can achieve the same heat dissipation and defrosting effect.

[0039] In one specific embodiment, the heat exchange structure 100 may further include, for example, a drive element 140 and a drive shaft, the drive shaft connecting the drive element 140 and all the fans. The drive element 140 simultaneously controls the rotation of all the fans, facilitating simultaneous control of all the fans to reverse for defrosting. At the same time, this reduces the number of drive elements 140, saving space occupied by the heat exchange structure 100.

[0040] The driving component 140 is, for example, a motor; the driving component 140 may be located outside the air inlet 114, outside the air outlet 115, or in the middle of the heat exchange pipe 110, and there is no limitation here.

[0041] Preferably, the drive shaft includes a first drive shaft 151 and a second drive shaft 152, and a drive member 140 connects the first drive shaft 151 and the second drive shaft 152, controlling the first drive shaft 151 and the second drive shaft 152 to rotate synchronously; the fan includes a first fan 131 disposed at the air inlet 114 and a second fan 132 disposed at the air outlet 115, the first drive shaft 151 is connected to the first fan 131, and the second drive shaft 152 is connected to the second fan 132. The drive member 140 can fully utilize the gap between the first fan 131 and the second fan 132, avoiding the drive member 140 occupying external space of the heat exchange structure 100, thereby facilitating the installation of the heat exchange structure 100 onto the outdoor unit of the air conditioner.

[0042] In one specific embodiment, the first fan 131 includes a first connector 131a and a first fan blade 131b surrounding the first connector 131a. The first connector 131a is mounted on the end of the first drive shaft 151 away from the drive member 140. The second fan 132 includes a second connector 132a and a second fan blade 132b surrounding the second connector 132a. The second connector 132a is mounted on the end of the second drive shaft 152 away from the drive member 140. Both the first fan blade 131b and the second fan blade 132b are bent towards the air inlet 114. When the drive member 140 controls the first fan 131 and the second fan 132 to rotate, the airflow generated by the first fan 131 and the second fan 132 is in the same direction, allowing the airflow to flow evenly within the first pipe 111 and the third pipe 113, further improving the heat exchange effect. Simultaneously, during defrosting, it facilitates the rapid discharge of blown-out frost from the heat exchange pipe 110.

[0043] In one specific embodiment, the heat exchanger 120 includes, for example, a shaft hole 121 located at the center of the second pipe 112, i.e., the shaft hole 121 is located at the center of the heat exchanger 120; the heat exchanger 120 also includes a plurality of heat exchange tubes and heat exchange fins surrounding the shaft hole 121; a first drive shaft 151 passes through the shaft hole 121, and a drive member 140 is located on the side of the heat exchanger 120 facing the second fan 132.

[0044] In this configuration, the second fan blade 132b faces the heat exchanger 120, meaning the second connector 132a is near the air outlet 115; the first fan blade 131b is near the air inlet 114, meaning a gap needs to be maintained between the first connector 131a and the air inlet 114 to prevent the first fan blade 131b from extending beyond the air inlet 114. At this time, the distance between the second connector 132a and the heat exchanger 120 is greater than the distance between the first connector 131a and the heat exchanger 120, providing more space to accommodate the drive component 140.

[0045] Preferably, the first drive shaft 151 is mounted in the shaft hole 121 via a bearing to achieve support and rotation. At the same time, the first drive shaft 151 is connected to the heat exchanger 120, and the drive component 140 is located on one side of the heat exchanger 120 and is not connected to the heat exchanger 120, which can avoid the drive component 140 occupying the heat exchange area of ​​the heat exchanger 120 and thus reducing the heat exchange effect.

[0046] In one specific embodiment, the heat exchange structure 100 further includes, for example, a first air guide duct 116, which connects the first pipe 111 and the second pipe 112. The diameter of the first air guide duct 116 gradually decreases along the direction from the first pipe 111 to the second pipe 112, and the side of the first air guide duct 116 facing the air inlet 114 forms a windward surface. The windward surface of the first air guide duct 116 can guide the air to the second pipe 112, and at the same time facilitate the introduction of blown frost into the second pipe 112, preventing frost from accumulating between the first pipe 111 and the second pipe 112.

[0047] In one specific embodiment, the heat exchange structure 100 further includes, for example, a second air duct 117, which connects the second pipe 112 and the third pipe 113. The diameter of the second air duct 117 gradually increases along the direction of the second pipe 112 and the third pipe 113, and the side of the second air duct 117 facing the air outlet 115 forms a leeward side. The second air duct 117 facilitates the rapid discharge of the heat-exchanged air and also facilitates the discharge of blown-out frost. When the drive unit 140 reverses, the fan reverses, and the functions of the first air duct 116 and the second air duct 117 are interchanged.

[0048] In one specific embodiment, the heat exchange structure 100 may further include a grille 160, which is disposed at the air inlet 114 and the air outlet 115. The grille 160 can prevent foreign objects from entering the heat exchange pipeline from the air outlet 115, ensuring the normal operation of the fan, heat exchanger 120 and drive unit 140; when the fan reverses direction, the air outlet 115 is used for air intake, and the grille 160 at the air outlet 115 can play the same role at this time, which will not be described in detail here.

[0049] [Second Embodiment]

[0050] On the other hand, the present invention also provides an air conditioner, including the heat exchange structure 100 provided in any of the above specific embodiments. The air conditioner includes an outdoor unit, and the external heating structure is located on the outdoor unit. Through the heat exchange structure 100, the air conditioner can increase the airflow velocity at the location of the heat exchanger 120, thereby improving the heat exchange effect and reducing the heat exchange area while maintaining the same heat exchange capacity, thus saving costs. Simultaneously, defrosting can be achieved by controlling the fan's rotation. In the defrost mode of the air conditioner, the fan operates independently, and the indoor heating does not need to be interrupted, avoiding any impact on user comfort.

[0051] [Third Embodiment]

[0052] On the other hand, see Figure 3 The present invention also provides a defrosting control method for an air conditioner outdoor unit, implemented through the heat exchange structure 100 provided in any of the above specific embodiments. The defrosting control method for the air conditioner outdoor unit includes, for example:

[0053] Step S1: Turn on the defrost mode of the air conditioner;

[0054] Step S2: Determine whether there is frost on the side of the heat exchange pipe 110 near the air inlet 114;

[0055] Step S3: If not, all fans will continue to blow air towards the air outlet 115;

[0056] Step S4: If so, all fans continuously blow air into the air inlet 114, and the air inlet 114 and the air outlet 115 are interchanged.

[0057] It should be noted that in step S1, the defrosting mode removes frost from the inner walls of the heat exchanger 120 and heat exchange pipe 110 through airflow generated by the fan. Therefore, it does not require the use of high-temperature refrigerant for defrosting and does not affect the heating function of the indoor unit. Thus, the defrosting mode can be activated in any mode of the indoor unit, such as the heating mode.

[0058] It should be noted that in steps S2-S4, the air conditioner reduces its inner diameter through the second pipe 112 to improve the heat exchange effect. If the side of the heat exchange pipe 110 near the air inlet 114 is not frosted, the fan keeps running at high speed, causing the heat exchanger 120 to heat up rapidly due to heat exchange, reducing frost accumulation and quickly dissipating the blown-out frost. Since frost mainly occurs on the windward side, switching the fan direction changes the windward side to the leeward side, which can quickly remove the frost on the windward side. After the windward and leeward sides are interchanged, if frost occurs on the new windward side, it can also be defrosted in time, thus continuously achieving the defrost effect.

[0059] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A heat exchange structure, characterized in that, include: A heat exchange pipe (110) includes a first pipe (111), a second pipe (112), and a third pipe (113) that are connected. The second pipe (112) is located between the first pipe (111) and the third pipe (113). The inner diameter of the second pipe (112) is smaller than that of the first pipe (111) and the inner diameter of the second pipe (112) is smaller than that of the third pipe (113). An air inlet (114) is formed on the side of the first pipe (111) away from the second pipe (112), and an air outlet (115) is formed on the side of the third pipe (113) away from the second pipe (112). Heat exchanger (120), the heat exchanger (120) is provided in the second pipeline (112); A fan is provided on the side of the heat exchange pipe (110) near the air inlet (114) and on the side of the heat exchange pipe (110) near the air outlet (115).

2. The heat exchange structure according to claim 1, characterized in that, The heat exchange structure further includes a drive unit (140) and a drive shaft, the drive shaft connecting the drive unit (140) and all the fans.

3. The heat exchange structure according to claim 2, characterized in that, The drive shaft includes a first drive shaft (151) and a second drive shaft (152), and the drive member (140) connects the first drive shaft (151) and the second drive shaft (152). The fan includes a first fan (131) located at the air inlet (114) and a second fan (132) located at the air outlet (115). The first drive shaft (151) is connected to the first fan (131), and the second drive shaft (152) is connected to the second fan (132).

4. The heat exchange structure according to claim 3, characterized in that, The first fan (131) includes a first connector (131a) and a first fan blade (131b) surrounding the first connector (131a), and the second fan (132) includes a second connector (132a) and a second fan blade (132b) surrounding the second connector (132a). Both the first fan blade (131b) and the second fan blade (132b) are bent toward the air inlet (114).

5. The heat exchange structure according to claim 3, characterized in that, The heat exchanger (120) includes a shaft hole (121) located at the center of the second pipeline (112), the first drive shaft (151) passing through the shaft hole (121), and the drive member (140) located on the side of the heat exchanger (120) facing the second fan (132).

6. The heat exchange structure according to any one of claims 1-5, characterized in that, The heat exchange structure also includes: The first air duct (116) is connected between the first pipeline (111) and the second pipeline (112). The diameter of the first air duct (116) gradually decreases along the direction from the first pipeline (111) to the second pipeline (112). The side of the first air duct (116) facing the air inlet (114) forms a windward surface.

7. The heat exchange structure according to any one of claims 1-5, characterized in that, The heat exchange structure also includes: The second air duct (117) is connected between the second pipe (112) and the third pipe (113). The diameter of the second air duct (117) gradually increases along the direction of the second pipe (112) and the third pipe (113). The side of the second air duct (117) facing the air outlet (115) forms a leeward side.

8. The heat exchange structure according to any one of claims 1-5, characterized in that, The heat exchange structure also includes: A grille (160) is provided at the air inlet (114) and the air outlet (115).

9. An air conditioner, characterized in that, Includes the heat exchange structure described in any one of claims 1-8.

10. A defrosting control method for an air conditioner outdoor unit, characterized in that, The defrosting control method for the outdoor unit of the air conditioner, achieved through the heat exchange structure described in any one of claims 1-8, includes: The air conditioner is in defrost mode. Determine whether the side of the heat exchange pipe (110) near the air inlet (114) is frosted; If not, all of the fans continuously blow air into the air outlet (115); If so, all the fans continuously blow air into the air inlet (114), and the air inlet (114) and the air outlet (115) are interchanged.

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