A heat pump system

Abstract

This invention relates to the field of refrigeration and heating technology, and discloses a heat pump system. The heat pump system includes a compressor, a first four-way valve, a shell-and-tube heat exchanger, an evaporator, a first pipeline, a second pipeline, and a control valve. The shell-and-tube heat exchanger has a first heat exchange flow path, a second heat exchange flow path, and a cooling water flow path. The first and second heat exchange flow paths exchange heat with the cooling water flow path within the shell-and-tube heat exchanger. The heat pump system can selectively connect the first and second pipelines via the first and / or second heat exchange flow paths through the control valve. Compared to existing technologies, the heat pump system of this invention can adjust the heat exchange area between the refrigerant in the first and second pipelines and the cooling medium within the shell-and-tube heat exchanger according to ambient temperature and user needs, thereby improving heat exchange efficiency and rationally controlling the energy consumption of the heat pump system.

Description

Technical Field

[0001] This invention relates to the field of refrigeration and heating technology, and more particularly to a heat pump system. Background Technology

[0002] Currently, heat pump systems typically use three types of condensers: coaxial heat exchangers, shell-and-tube heat exchangers, and plate heat exchangers. Shell-and-tube heat exchangers have a relatively simple structural layout and their dimensions are not easily adjustable; plate heat exchangers, while small in size, have poor corrosion resistance and freeze resistance, and are prone to clogging. Coaxial heat exchangers, on the other hand, have good freeze resistance, are resistant to fouling and clogging, and their size and structural layout can be flexibly selected, resulting in a high heat transfer coefficient.

[0003] However, existing shell-and-tube heat exchangers are all single-flow-path. During refrigeration, the evaporation pressure loss of a single-flow-path is high and the heat exchange is insufficient, resulting in a low refrigeration heat transfer coefficient of the shell-and-tube heat exchanger and low heat exchange efficiency of the heat pump system. If the volume of the heat exchanger is increased, the cost will increase, which will affect the economics of the heat pump system. Summary of the Invention

[0004] Based on the above problems, the purpose of this invention is to provide a heat pump system that has high heat exchange efficiency and is economical and practical.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A heat pump system is provided, including a compressor, a first four-way valve, a shell-and-tube heat exchanger, an evaporator, a first pipe, a second pipe, and a control valve. The shell-and-tube heat exchanger has a first heat exchange path and a second heat exchange path. The control valve is configured to control the first pipe and the second pipe to be selectively connected through the first heat exchange path and / or the second heat exchange path.

[0007] As a preferred embodiment of the heat pump system of the present invention, both the first pipeline and the second pipeline are provided with control valves. The control valve on the first pipeline is a first three-way valve, and the control valve on the second pipeline is a second three-way valve. One end of the first heat exchange flow path is connected to the first interface of the first three-way valve, and the other end is connected to the first interface of the second three-way valve. One end of the second heat exchange flow path is connected to the second interface of the first three-way valve, and the other end is connected to the second interface of the second three-way valve. The third interface of the first three-way valve is connected to the first pipeline, and the third interface of the second three-way valve is connected to the second pipeline.

[0008] As a preferred embodiment of the heat pump system of the present invention, the control valve is provided on the first pipeline or the second pipeline. The control valve is configured to control the first pipeline, the first heat exchange flow path, and the second pipeline to be connected in sequence, or to control the first pipeline, the first heat exchange flow path, the second heat exchange flow path, and the second pipeline to be connected in sequence.

[0009] As a preferred embodiment of the heat pump system of the present invention, the control valve is disposed on the second pipeline. The control valve is a second four-way valve. One end of the first heat exchange flow path is connected to the first pipeline, and the other end is connected to the E port of the second four-way valve. One end of the second heat exchange flow path is connected to the D port of the second four-way valve, and the other end is connected to the C port of the second four-way valve. The S port of the second four-way valve is connected to the second pipeline.

[0010] As a preferred embodiment of the heat pump system of the present invention, the control valve is provided on the first pipeline or the second pipeline, and the control valve is configured to control the sequential connection of the first pipeline, the first heat exchange flow path, the second heat exchange flow path, and the second pipeline.

[0011] As a preferred embodiment of the heat pump system of the present invention, the control valve is disposed on the first pipeline, the control valve is a third four-way valve, one end of the first heat exchange flow path is connected to the S interface of the third four-way valve, and the other end is connected to the D interface of the third four-way valve, one end of the second heat exchange flow path is connected to the E interface of the third four-way valve, and the other end is connected to the second pipeline, and the C interface of the third four-way valve is connected to the first pipeline.

[0012] As a preferred embodiment of the heat pump system of the present invention, the heat pump system further includes a third pipeline and a fourth pipeline. One end of the third pipeline is connected to the output end of the compressor, and the other end is connected to the D port of the first four-way valve. The C port of the first four-way valve is connected to the first pipeline. One end of the fourth pipeline is connected to the evaporator, and the other end is connected to the E port of the first four-way valve.

[0013] As a preferred embodiment of the heat pump system of the present invention, the heat pump system further includes a fifth pipeline, one end of which is connected to the S-port of the first four-way valve, and the other end is connected to the input end of the compressor. A liquid storage tank is provided on the fifth pipeline for storing liquid refrigerant.

[0014] As a preferred embodiment of the heat pump system of the present invention, the heat pump system further includes a heat accumulator located on the fourth pipe and the fifth pipe.

[0015] As a preferred embodiment of the heat pump system of the present invention, an expansion valve is provided on the second pipeline. The expansion valve is used to throttle the refrigerant in the second pipeline and control the flow rate of the refrigerant in the second pipeline.

[0016] The beneficial effects of this invention are as follows:

[0017] The heat pump system provided by this invention includes a shell-and-tube heat exchanger with a first heat exchange flow path and a second heat exchange flow path. By installing control valves on the first and / or second pipes, the heat pump system can selectively connect the first and second pipes via the first and / or second heat exchange flow paths, thereby adjusting the heat exchange area between the refrigerant in the first and second pipes and the cooling medium inside the shell-and-tube heat exchanger according to actual needs, thus improving heat exchange efficiency. Compared to existing technologies, the heat pump system of this invention can adjust the heat exchange area between the refrigerant in the first and second pipes and the cooling medium inside the shell-and-tube heat exchanger according to ambient temperature and user needs, thereby improving heat exchange efficiency and rationally controlling the energy consumption of the heat pump system. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the internal structure of the shell-and-tube heat exchanger provided in a specific embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the heat pump system provided in the first embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the heat pump system provided in the second embodiment of the present invention;

[0022] Figure 4 This is a first structural schematic diagram of the heat pump system provided in the third embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the second structure of the heat pump system provided in the third embodiment of the present invention.

[0024] In the picture:

[0025] 1-Compressor; 2-First four-way valve; 3-Shell-tube heat exchanger; 4-Evaporator; 5-First piping; 6-Second

[0026] Piping; 7-Third Piping; 8-Fourth Piping; 9-Fifth Piping; 10-Heat Accumulator;

[0027] 31-First heat exchange path; 32-Second heat exchange path; 33-Cooling water path;

[0028] 41-Fan;

[0029] 51-First three-way valve; 52-Third four-way valve;

[0030] 61-Second three-way valve; 62-Second four-way valve; 63-Expansion valve;

[0031] 91-Liquid storage tank. Detailed Implementation

[0032] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0035] Example 1

[0036] like Figure 1 and Figure 2 As shown, this embodiment provides a heat pump system, which includes a compressor 1, a first four-way valve 2, a shell-and-tube heat exchanger 3, an evaporator 4, a first pipeline 5, a second pipeline 6, and a control valve. The shell-and-tube heat exchanger 3 has a first heat exchange flow path 31 and a second heat exchange flow path 32. The control valve is configured to control the first pipeline 5 and the second pipeline 6 to be selectively connected through the first heat exchange flow path 31 and / or the second heat exchange flow path 32.

[0037] See Figure 1In this embodiment, the shell-and-tube heat exchanger 3 also includes a cooling water flow path 33. Both the first heat exchange flow path 31 and the second heat exchange flow path 32 can exchange heat with the cooling water flow path 33 to achieve cooling or heating. Furthermore, the heat exchange tubes of the first heat exchange flow path 31 and the second heat exchange flow path 32 are arranged in different directions. Figure 1 In the heat exchanger 3, the first heat exchange path 31 is perpendicular to the second heat exchange path 32, and their heat exchange areas are roughly equivalent. However, the length of the first heat exchange path 31 is greater than the length of the second heat exchange path 32, and the number of heat exchange tubes in the first heat exchange path 31 is greater than the number of heat exchange tubes in the second heat exchange path 32. Therefore, the heat exchange resistance loss of the shell-and-tube heat exchanger 3 is smaller, and the heat exchange is more efficient. The cooling water flow path 33 can be a round tube, an elliptical tube, or a flat tube, etc., selected according to design requirements.

[0038] The heat pump system provided in this embodiment, by setting control valves on the first pipe 5 and / or the second pipe 6, enables the heat pump system to selectively connect the first pipe 5 and the second pipe 6 via the first heat exchange flow path 31 and / or the second heat exchange flow path 32, thereby adjusting the heat exchange area between the refrigerant in the first pipe 5 and the second pipe 6 and the cooling medium in the shell-and-tube heat exchanger 3 according to actual needs, and improving the heat exchange efficiency.

[0039] Optionally, see Figure 2 An expansion valve 63 is installed on the second pipeline 6. The expansion valve 63 is used to throttle the refrigerant in the second pipeline 6 and control the flow rate of the refrigerant. The high-temperature and high-pressure liquid refrigerant becomes low-temperature and low-pressure hydraulic refrigerant after being throttled through the throttling orifice of the expansion valve 63, creating conditions for the evaporation of the refrigerant. The liquid refrigerant entering the evaporator 4 evaporates from liquid to gas after passing through the evaporator 4, absorbing heat and achieving refrigeration. By controlling the flow rate of the refrigerant through the expansion valve 63, it is ensured that the outlet of the evaporator 4 is entirely gaseous refrigerant. If the flow rate is too high, the outlet of the evaporator 4 will contain liquid refrigerant, which may easily cause liquid slugging when it enters the compressor 1; if the refrigerant flow rate is too low, the refrigerant will evaporate prematurely, resulting in insufficient refrigeration.

[0040] Optionally, see Figure 2 The heat pump system also includes a third pipe 7, a fourth pipe 8, and a fifth pipe 9. One end of the third pipe 7 is connected to the output of the compressor 1, and the other end is connected to the D port of the first four-way valve 2. The C port of the first four-way valve 2 is connected to the first pipe 5. One end of the fourth pipe 8 is connected to the evaporator 4, and the other end is connected to the E port of the first four-way valve 2. One end of the fifth pipe 9 is connected to the S port of the first four-way valve 2, and the other end is connected to the input of the compressor 1. The heat pump system achieves internal circulation through the first pipe 5, the second pipe 6, the third pipe 7, the fourth pipe 8, and the fifth pipe 9.

[0041] Optionally, see Figure 2Control valves are installed on both the first pipeline 5 and the second pipeline 6. The control valve on the first pipeline 5 is a first three-way valve 51, and the control valve on the second pipeline 6 is a second three-way valve 61. One end of the first heat exchange flow path 31 is connected to the first interface of the first three-way valve 51, and the other end is connected to the first interface of the second three-way valve 61. One end of the second heat exchange flow path 32 is connected to the second interface of the first three-way valve 51, and the other end is connected to the second interface of the second three-way valve 61. The third interface of the first three-way valve 51 is connected to the first pipeline 5, and the third interface of the second three-way valve 61 is connected to the second pipeline 6.

[0042] Specifically, when rapid heating or cooling is required to increase the heat exchange area, all three ports of the first three-way valve 51 and the three ports of the second three-way valve 61 are opened. The opening and closing of each port of the first three-way valve 51 and the second three-way valve 61 can be controlled according to the ambient temperature or user needs. (See also...) Figure 2 During heating, the first four-way valve 2 is de-energized, and its DC and SE sections are open. Refrigerant is discharged from the output end of compressor 1 and flows into the first pipe 5 through the third pipe 7 and the DC section of the first four-way valve 2. The refrigerant in the first pipe 5 enters the shell-and-tube heat exchanger 3 through port a of the first heat exchange flow path 31 and port b of the second heat exchange flow path 32, respectively, and exchanges heat with the cooling water flow path 33 of the shell-and-tube heat exchanger 3. After heat exchange, the refrigerant flows into the second pipe 6 through port a' of the first heat exchange flow path 31 and port b' of the second heat exchange flow path 32, respectively. At this time, the refrigerant is in a high-pressure, medium-temperature state. After being throttled by the expansion valve 63, it enters the evaporator 4 to absorb heat from the air, and then returns to the input end of compressor 1 through the SE section of the first four-way valve 2 and the fifth pipe 9, completing the heating cycle.

[0043] Similarly, during cooling, the first four-way valve 2 is energized, and sections DE and CS are open. Refrigerant is discharged from the compressor 1 output, flows through the third pipe 7 and the DE section of the first four-way valve 2 into the fourth pipe 8, enters the evaporator 4, and then is throttled by the expansion valve 63 to become a low-temperature, low-pressure liquid refrigerant. This low-temperature, low-pressure liquid refrigerant enters the shell-and-tube heat exchanger 3 through port a' of the first heat exchange path 31 and port b' of the second heat exchange path 32, respectively, and exchanges heat with the cooling water flow path 33 of the shell-and-tube heat exchanger 3. After heat exchange, the refrigerant flows back into the first pipe 5 through port a of the first heat exchange path 31 and port b of the second heat exchange path 32, and then returns to the compressor 1 input through the CS section of the first four-way valve 2 and the fifth pipe 9, completing the refrigeration cycle. Because the refrigerant flows through both the first heat exchange path 31 and the second heat exchange path 32 of the shell-and-tube heat exchanger 3 simultaneously during both cooling and heating, the heat exchange area can be increased, improving heat exchange efficiency.

[0044] When rapid cooling or heating is not required, the first or second port of the first three-way valve 51 can be closed, and the corresponding first or second port of the second three-way valve 61 can also be closed. In this case, during the cooling and heating process, the refrigerant only flows through the first heat exchange path 31 or the second heat exchange path 32 of the shell-and-tube heat exchanger 3, and exchanges heat with the cooling water path 33 through a single heat exchange path. This makes control convenient and reduces the energy consumption of the heat pump system, meeting the different usage needs of users.

[0045] Optionally, see Figure 2 A liquid receiver 91 is installed on the fifth pipeline 9. The liquid receiver 91 is used to store refrigerant. When the evaporation load of the evaporator 4 increases, the required refrigerant supply also increases. At this time, the liquid receiver 91 can replenish the required refrigerant. When the evaporation load of the evaporator 4 decreases, the excess refrigerant can be stored in the liquid receiver 91. In addition, the liquid receiver 91 can act as a liquid seal to prevent gas from entering the compressor 1 and causing liquid slugging.

[0046] Furthermore, in this embodiment, a fan 41 is provided on the evaporator 4. The fan 41 is used to accelerate the heat exchange of the evaporator 4 and further improve the heat exchange efficiency.

[0047] Compared to existing technologies, the heat pump system provided in this embodiment can adjust the heat exchange area between the refrigerant in the first pipeline 5 and the second pipeline 6 and the cooling medium in the shell-and-tube heat exchanger 3 according to the ambient temperature and user needs, thereby improving the heat exchange efficiency and reasonably controlling the energy consumption of the heat pump system.

[0048] Example 2

[0049] like Figure 1 and Figure 3 As shown, this embodiment provides a heat pump system, wherein components that are the same as or corresponding to those in Embodiment 1 are labeled with the same reference numerals as those in Embodiment 1. For simplicity, only the differences between Embodiment 2 and Embodiment 1 are described. The differences are as follows:

[0050] In this embodiment, optionally, a control valve is provided on the first pipeline 5 or the second pipeline 6. The control valve is configured to control the first pipeline 5, the first heat exchange flow path 31, and the second pipeline 6 to be connected in sequence, or to control the first pipeline 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipeline 6 to be connected in sequence.

[0051] In this embodiment, by setting a control valve on the first pipe 5 or the second pipe 6, the heat pump system can control the sequential connection of the first pipe 5, the first heat exchange flow path 31, and the second pipe 6, or control the sequential connection of the first pipe 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipe 6, thereby adjusting the heat exchange area between the refrigerant in the first pipe 5 and the second pipe 6 and the cooling medium in the shell-and-tube heat exchanger 3 according to actual needs, and improving the heat exchange efficiency.

[0052] Optionally, see Figure 3 Taking the control valve set on the second pipeline 6 as an example, the control valve is the second four-way valve 62. One end of the first heat exchange flow path 31 is connected to the first pipeline 5, and the other end is connected to the E interface of the second four-way valve 62. One end of the second heat exchange flow path 32 is connected to the D interface of the second four-way valve 62, and the other end is connected to the C interface of the second four-way valve 62. The S interface of the second four-way valve 62 is connected to the second pipeline 6.

[0053] (i) When heating, the first four-way valve 2 is de-energized, and its DC and SE sections are open. The second four-way valve 62 can be energized or de-energized depending on the ambient temperature and user requirements.

[0054] When the second four-way valve 62 is energized, its DE and CS sections are open. Refrigerant is discharged from the output end of compressor 1, flows through the third pipe 7 and the DC section of the first four-way valve 2 into the first pipe 5. The refrigerant in the first pipe 5 enters the shell-and-tube heat exchanger 3 through port c of the first heat exchange flow path 31, and flows out through port c' of the first heat exchange flow path 31. Then, it enters the shell-and-tube heat exchanger 3 again through the DE section of the second four-way valve 62 and the d port of the second heat exchange flow path 32, and flows out through the d' port of the second heat exchange flow path 32. It then flows into the second pipe 6 through the CS section of the second four-way valve 62. At this time, the refrigerant is in a high-pressure, medium-temperature state. After being throttled by the expansion valve 63, it enters the evaporator 4 to absorb heat from the air, and then returns to the input end of compressor 1 through the SE section of the first four-way valve 2 and the fifth pipe 9, completing the heating cycle. Since the refrigerant flows through the first heat exchange path 31 and the second heat exchange path 32 of the shell-and-tube heat exchanger 3 simultaneously during heating, the heat exchange area can be increased and the heat exchange efficiency can be improved.

[0055] When the second four-way valve 62 is de-energized, its DC and SE sections are open. Refrigerant is discharged from the output of compressor 1, flows through the third pipe 7 and the DC section of the first four-way valve 2 into the first pipe 5. The refrigerant in the first pipe 5 enters the shell-and-tube heat exchanger 3 through port c of the first heat exchange path 31, and flows out through port c' of the first heat exchange path 31. It then flows into the second pipe 6 through the SE section of the second four-way valve 62. At this time, the refrigerant is in a high-pressure, medium-temperature state. It passes through the expansion valve 63 and enters the evaporator 4 to absorb heat from the air. Then, it returns to the input of compressor 1 through the SE section of the first four-way valve 2 and the fifth pipe 9, completing the heating cycle. At this time, the refrigerant only flows through the first heat exchange path 31 of the shell-and-tube heat exchanger 3, exchanging heat with the cooling water path 33 through a single heat exchange path, reducing the energy consumption of the heat pump system and meeting different user needs.

[0056] (ii) During cooling, the first four-way valve 2 is energized, and sections DE and CS are open. The second four-way valve 62 can be energized or de-energized depending on the ambient temperature and user requirements.

[0057] When the second four-way valve 62 is energized, its DE and CS sections are open. Refrigerant is discharged from the output of compressor 1, flows through the third pipe 7 and the DE section of the first four-way valve 2 into the fourth pipe 8, and enters the evaporator 4. Then, it is throttled by the expansion valve 63 to become a low-temperature, low-pressure liquid refrigerant. This low-temperature, low-pressure liquid refrigerant flows through the SC section of the second four-way valve 62 and the d' port of the second heat exchange path 32 into the shell-and-tube heat exchanger 3, and flows out through the d port of the second heat exchange path 32. Subsequently, it flows through the DE section of the second four-way valve 62 and the c' port of the first heat exchange path 31 into the shell-and-tube heat exchanger 3, and flows through the c port of the first heat exchange path 31 into the first pipe 5. Finally, it returns to the input of compressor 1 through the CS section of the first four-way valve 2 and the fifth pipe 9, completing the refrigeration cycle. Because the refrigerant flows through both the first heat exchange path 31 and the second heat exchange path 32 of the shell-and-tube heat exchanger 3 simultaneously during refrigeration, the heat exchange area can be increased, improving heat exchange efficiency.

[0058] When the second four-way valve 62 is de-energized, its DC and SE sections are open. Refrigerant is discharged from the output of compressor 1, flows through the third pipe 7 and the DE section of the first four-way valve 2 into the fourth pipe 8, and enters the evaporator 4. Then, it is throttled by the expansion valve 63 to become a low-temperature, low-pressure liquid refrigerant. This low-temperature, low-pressure liquid refrigerant flows through the SE section of the second four-way valve 62 and the c' port of the first heat exchange path 31 into the shell-and-tube heat exchanger 3, and then flows through the c port of the first heat exchange path 31 into the first pipe 5. Finally, it returns to the input of compressor 1 through the CS section of the first four-way valve 2 and the fifth pipe 9, completing the refrigeration cycle. During this process, the refrigerant only flows through the first heat exchange path 31 of the shell-and-tube heat exchanger 3, exchanging heat with the cooling water path 33 through a single heat exchange path, making control convenient and meeting different user needs.

[0059] Compared to existing technologies, the heat pump system provided in this embodiment can adjust the heat exchange area between the refrigerant in the first pipeline 5 and the second pipeline 6 and the cooling medium in the shell-and-tube heat exchanger 3 through the second four-way valve 62 according to the ambient temperature and user needs, thereby improving the heat exchange efficiency and reasonably controlling the energy consumption of the heat pump system.

[0060] In other embodiments, a control valve may also be provided on the first pipeline 5 so that the control valve can control the first pipeline 5, the first heat exchange flow path 31, and the second pipeline 6 to be connected in sequence, or control the first pipeline 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipeline 6 to be connected in sequence, thereby adjusting the heat exchange area between the refrigerant in the first pipeline 5 and the second pipeline 6 and the cooling medium in the shell-and-tube heat exchanger 3.

[0061] Example 3

[0062] like Figure 1 , Figure 4 and Figure 5 As shown, this embodiment provides a heat pump system, wherein components that are the same as or corresponding to those in Embodiment 1 are marked with the same reference numerals as those in Embodiment 1. For simplicity, only the differences between Embodiment 3 and Embodiment 1 are described. The differences are as follows:

[0063] In this embodiment, optionally, a control valve is provided on the first pipeline 5 or the second pipeline 6. The control valve is configured to control the sequential connection of the first pipeline 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipeline 6.

[0064] By installing a control valve on the first pipe 5 or the second pipe 6, the first pipe 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipe 6 are connected sequentially in the heat pump system, whether it is heating or cooling. This allows the refrigerant in the first pipe 5 and the second pipe 6 to fully exchange heat with the cooling medium in the shell-and-tube heat exchanger 3, effectively improving the heat exchange efficiency.

[0065] Optionally, see Figure 4 Taking the control valve set on the first pipeline 5 as an example, the control valve is the third four-way valve 52. One end of the first heat exchange flow path 31 is connected to the S interface of the third four-way valve 52, and the other end is connected to the D interface of the third four-way valve 52. One end of the second heat exchange flow path 32 is connected to the E interface of the third four-way valve 52, and the other end is connected to the second pipeline 6. The C interface of the third four-way valve 52 is connected to the first pipeline 5.

[0066] During heating, the first four-way valve 2 is de-energized, with its DC and SE sections open. The third four-way valve 52 is also de-energized, with its DC and SE sections open. Refrigerant is discharged from the output of compressor 1, flows through the third pipe 7 and the DC section of the first four-way valve 2 into the first pipe 5. The refrigerant in the first pipe 5 enters the shell-and-tube heat exchanger 3 through the DC section of the third four-way valve 52 and the e' port of the first heat exchange flow path 31, and flows out through the e port of the first heat exchange flow path 31. Then, it enters the shell-and-tube heat exchanger 3 through the SE section of the third four-way valve 52 and the f port of the second heat exchange flow path 32, and flows into the second pipe 6 through the f' port of the second heat exchange flow path 32. At this time, the refrigerant is in a high-pressure, medium-temperature state. After being throttled by the expansion valve 63, it enters the evaporator 4 to absorb heat from the air, and then returns to the input of compressor 1 through the SE section of the first four-way valve 2 and the fifth pipe 9, completing the heating cycle. Since the refrigerant flows through the first heat exchange path 31 and the second heat exchange path 32 of the shell-and-tube heat exchanger 3 simultaneously during heating, the heat exchange area can be increased and the heat exchange efficiency can be improved.

[0067] During refrigeration, the first four-way valve 2 is energized, with its DE and CS sections open. The third four-way valve 52 is also de-energized, with its DE and CS sections open. Refrigerant is discharged from the output of compressor 1, flows through the third pipe 7 and the DE section of the first four-way valve 2 into the fourth pipe 8, enters the evaporator 4, and then is throttled by expansion valve 63 to become low-temperature, low-pressure liquid refrigerant. The low-temperature, low-pressure liquid refrigerant enters the shell-and-tube heat exchanger 3 through the f' port of the second heat exchange flow path 32, and flows out through the f port of the second heat exchange flow path 32. Subsequently, it enters the shell-and-tube heat exchanger 3 through the DE section of the third four-way valve 52 and the e' port of the first heat exchange flow path 31, and flows into the first pipe 5 through the e port of the first heat exchange flow path 31 and the CS section of the third four-way valve 52. Finally, it returns to the input of compressor 1 through the CS section of the first four-way valve 2 and the fifth pipe 9, completing the refrigeration cycle. Since the refrigerant flows through the first heat exchange path 31 and the second heat exchange path 32 of the shell-and-tube heat exchanger 3 simultaneously during refrigeration, the heat exchange area can be increased and the heat exchange efficiency can be improved.

[0068] In other embodiments, the control valve may be installed on the second pipeline 6 so that the control valve can control the first pipeline 5, the first heat exchange flow path 31, the second heat exchange flow path 32, and the second pipeline 6 to be connected in sequence, so as to ensure that the refrigerant in the first pipeline 5 and the second pipeline 6 can fully exchange heat with the cooling medium in the shell-and-tube heat exchanger 3.

[0069] Optionally, see Figure 5The heat pump system also includes a heat accumulator 10, which is located on the fourth pipe 8 and the fifth pipe 9. During defrosting, the first four-way valve 2 is energized, with its DE and CS sections open. The third four-way valve 52 is de-energized, with its DC and SE sections open. Refrigerant is discharged from the output of the compressor 1, enters the heat accumulator 10 through the DE section of the first four-way valve 2 and the fourth pipe 8, thereby accumulating some heat. It then dissipates heat in the evaporator 4 to defrost, and subsequently flows through the expansion valve 63 to become a low-temperature, low-pressure liquid refrigerant. The low-temperature, low-pressure liquid refrigerant enters the shell-and-tube heat exchanger 3 through the f' port of the second heat exchange flow path 32, and flows out through the f port of the second heat exchange flow path 32. It then enters the shell-and-tube heat exchanger 3 through the SE section of the third four-way valve 52 and the e port of the first heat exchange flow path 31. The refrigerant flows through the tube heat exchanger 3 and into the first pipeline 5 via the e' port of the first heat exchange flow path 31 and the DC section of the third four-way valve 52. During this process, the water flow rate in the cooling water flow path 33 of the tube heat exchanger 3 needs to be reduced to avoid a large amount of heat loss, thereby preventing incomplete evaporation of the refrigerant. The gas-liquid two-phase refrigerant flows sequentially through the CS section of the first four-way valve 2, the fifth pipeline 9, and the heat accumulator 10. After absorbing the heat from the heat accumulator 10, the gas-liquid two-phase refrigerant becomes superheated steam and returns to the input end of the compressor 1 to complete the defrosting.

[0070] Compared to existing technologies, the heat pump system provided in this embodiment can improve heat exchange efficiency by adjusting the heat exchange area between the refrigerant in the first pipeline 5 and the second pipeline 6 and the cooling medium in the shell-and-tube heat exchanger 3 through the third four-way valve 52, according to ambient temperature and user needs.

[0071] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A heat pump system, characterized in that, The device includes a compressor (1), a first four-way valve (2), a shell-and-tube heat exchanger (3), an evaporator (4), a first pipeline (5), a second pipeline (6), and a control valve. The shell-and-tube heat exchanger (3) has a first heat exchange flow path (31) and a second heat exchange flow path (32). The control valve is configured to control the first pipeline (5) and the second pipeline (6) to be selectively connected through the first heat exchange flow path (31) and / or the second heat exchange flow path (32). The first pipeline (5) and the second pipeline (6) are both equipped with the control valve. The control valve on the first pipeline (5) is a first three-way valve (51), and the control valve on the second pipeline (6) is a second three-way valve (61). One end of the first heat exchange flow path (31) is connected to the first interface of the first three-way valve (51), and the other end is connected to the first interface of the second three-way valve (61). One end of the second heat exchange flow path (32) is connected to the second interface of the first three-way valve (51), and the other end is connected to the second interface of the second three-way valve (61). The third interface of the first three-way valve (51) is connected to the first pipeline (5), and the third interface of the second three-way valve (61) is connected to the second pipeline (6).

2. A heat pump system, characterized in that, The device includes a compressor (1), a first four-way valve (2), a shell-and-tube heat exchanger (3), an evaporator (4), a first pipeline (5), a second pipeline (6), and a control valve. The shell-and-tube heat exchanger (3) has a first heat exchange flow path (31) and a second heat exchange flow path (32). The control valve is configured to control the first pipeline (5) and the second pipeline (6) to be selectively connected through the first heat exchange flow path (31) and / or the second heat exchange flow path (32). The control valve is provided on the first pipeline (5) or the second pipeline (6). The control valve is configured to control the first pipeline (5), the first heat exchange flow path (31), and the second pipeline (6) to be connected in sequence, or to control the first pipeline (5), the first heat exchange flow path (31), the second heat exchange flow path (32), and the second pipeline (6) to be connected in sequence. The control valve is installed on the second pipeline (6). The control valve is a second four-way valve (62). One end of the first heat exchange flow path (31) is connected to the first pipeline (5), and the other end is connected to the E interface of the second four-way valve (62). One end of the second heat exchange flow path (32) is connected to the D interface of the second four-way valve (62), and the other end is connected to the C interface of the second four-way valve (62). The S interface of the second four-way valve (62) is connected to the second pipeline (6).

3. A heat pump system, characterized in that, The device includes a compressor (1), a first four-way valve (2), a shell-and-tube heat exchanger (3), an evaporator (4), a first pipeline (5), a second pipeline (6), and a control valve. The shell-and-tube heat exchanger (3) has a first heat exchange flow path (31) and a second heat exchange flow path (32). The control valve is configured to control the first pipeline (5) and the second pipeline (6) to be selectively connected through the first heat exchange flow path (31) and / or the second heat exchange flow path (32). The control valve is provided on the first pipeline (5) or the second pipeline (6), and the control valve is configured to control the first pipeline (5), the first heat exchange flow path (31), the second heat exchange flow path (32), and the second pipeline (6) to be connected in sequence; The control valve is installed on the first pipeline (5). The control valve is a third four-way valve (52). One end of the first heat exchange flow path (31) is connected to the S interface of the third four-way valve (52), and the other end is connected to the D interface of the third four-way valve (52). One end of the second heat exchange flow path (32) is connected to the E interface of the third four-way valve (52), and the other end is connected to the second pipeline (6). The C interface of the third four-way valve (52) is connected to the first pipeline (5).

4. The heat pump system according to any one of claims 1-3, characterized in that, The heat pump system also includes a third pipe (7) and a fourth pipe (8). One end of the third pipe (7) is connected to the output end of the compressor (1), and the other end is connected to the D port of the first four-way valve (2). The C port of the first four-way valve (2) is connected to the first pipe (5). One end of the fourth pipe (8) is connected to the evaporator (4), and the other end is connected to the E port of the first four-way valve (2).

5. The heat pump system according to claim 4, characterized in that, The heat pump system also includes a fifth pipeline (9), one end of which is connected to the S port of the first four-way valve (2), and the other end is connected to the input end of the compressor (1). A liquid storage tank (91) is provided on the fifth pipeline (9), and the liquid storage tank (91) is used to store liquid refrigerant.

6. The heat pump system according to claim 5, characterized in that, The heat pump system also includes a heat accumulator (10) located on the fourth pipe (8) and the fifth pipe (9).

7. The heat pump system according to any one of claims 1-3, characterized in that, An expansion valve (63) is provided on the second pipeline (6). The expansion valve (63) is used to throttle the refrigerant in the second pipeline (6) and control the flow rate of the refrigerant in the second pipeline (6).

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