Refrigerant pumps and refrigeration systems

Abstract

The application provides a refrigerant pump and a refrigeration system. The refrigerant pump comprises a pump body, a first liquid accumulator, a suction port, a cylinder, a return pipe, a liquid inlet pipe, a liquid level pipe and a degassing pipe. The return pipe and the liquid inlet pipe are respectively arranged at the axial two ends of the cylinder. The return pipe is communicated with the suction port. The first end of the liquid level pipe is arranged on the side wall of the cylinder. The degassing pipe is communicated with the liquid inlet pipe and the liquid level pipe. The refrigerant pump is provided with the liquid level pipe. The liquid level pipes of the refrigerant pumps connected in parallel are communicated with each other. When the liquid level of the refrigerant in the first liquid accumulator is uneven, the refrigerant with high liquid level flows to the refrigerant with low liquid level, so that the liquid is uniform. The refrigerant entering the first liquid accumulator through the liquid level pipe is degassed by the degassing pipe, so that the cavitation in the pump body is prevented and the pump body is not damaged.

Description

Technical Field

[0001] This invention relates to the field of refrigeration technology, specifically to a refrigerant pump and a refrigeration system. Background Technology

[0002] With the rapid development of the telecommunications industry, the heat generated by individual data center racks is increasing, with some racks exceeding 20kW. To ensure the racks operate normally without being affected by temperature, in-row air conditioners are currently the primary method for cooling. In-row air conditioners typically come with their own compressors and evaporators, corresponding one-to-one with outdoor units, which consist of a refrigerant pump and a condenser.

[0003] During winter and transitional seasons (spring and autumn), conventional compressor refrigeration suffers from low condensing temperatures due to low outdoor ambient temperatures, which can easily lead to refrigerant buildup and poor lubrication within the compressor casing, causing reliability issues. Therefore, refrigerant pumps are typically used during winter and transitional seasons, utilizing natural outdoor cooling sources and sharing a single outdoor unit to supply refrigerant cooling to the indoor units of each row of air conditioners. When one refrigerant pump cannot meet the flow requirements, two or more refrigerant pumps with identical characteristics can be connected in parallel. For some large pumps requiring a standby pump, two pumps (each with 50% flow rate) can also be used in parallel, with one pump on standby, i.e., a two-on-one-on-standby configuration.

[0004] However, conventional refrigerant pumps, when operating at high speeds, are prone to uneven liquid flow distribution in the pipeline. The low saturation pressure of the liquid refrigerant at the pump's suction port can cause a sudden drop in suction pressure, leading to cavitation. This causes the liquid refrigerant to flash into a gaseous state, which then blocks the pump's suction port, resulting in unstable flow and making it difficult for the refrigeration system to operate stably. Furthermore, when multiple refrigerant pumps are connected in parallel, uneven refrigerant distribution can affect the refrigeration efficiency of the system and may even damage the pumps. Summary of the Invention

[0005] In view of the problems in the prior art, the purpose of this invention is to provide a refrigerant pump and a refrigeration system to improve the stability of refrigerant pump operation.

[0006] This invention provides a refrigerant pump, comprising:

[0007] Pump body, including the suction port;

[0008] The first liquid reservoir includes a cylinder, a return pipe, an inlet pipe, a level pipe, and a degassing pipe; the return pipe and the inlet pipe are respectively located at the two axial ends of the cylinder; the return pipe is connected to the suction port; the level pipe is located on the side wall of the cylinder; and the degassing pipe connects the inlet pipe and the level pipe.

[0009] In some embodiments, the first end of the degassing pipe is disposed on the side wall of the liquid inlet pipe, and the second end of the degassing pipe is disposed on the side wall of the liquid level pipe.

[0010] In some embodiments, the maximum diameter of the liquid level tube is D, and the diameter of the degassing tube is d, satisfying: 1.4 < d / D < 0.32.

[0011] In some embodiments, the distance between the liquid level tube and the suction port is H, where H is greater than 30 mm.

[0012] In some embodiments, the second ends of the level tubes of a plurality of refrigerant pumps connected in parallel are connected to each other by a pipeline, the pipeline including a first branch pipe and a second branch pipe, the first end of the first branch pipe being connected to the second end of the level tube, and the second ends of the plurality of first branch pipes being connected to the second branch pipe.

[0013] In some embodiments, the second ends of a plurality of the first branches are located on the same horizontal plane.

[0014] In some embodiments, the refrigerant pump further includes a housing and a motor, with the pump body and the motor located inside the housing; the pump body includes a cylinder, an upper cylinder head, a lower cylinder head, a crankshaft, and a rolling rotor; the upper cylinder head and the lower cylinder head are respectively located at the two axial ends of the cylinder; the crankshaft extends through both ends of the cylinder; the rolling rotor is sleeved on the eccentric portion of the crankshaft and located inside the cylinder; the motor includes a stator and a rotor arranged coaxially with the stator, the rotor being connected to the crankshaft.

[0015] In some embodiments, the cylinder includes a cylinder cavity, and the cylinder is radially provided with a blade groove communicating with the cylinder cavity and a spring hole communicating with the blade groove. A blade is provided in the blade groove, and a spring is installed in the spring hole. The two ends of the blade abut against the rolling rotor and the spring, respectively.

[0016] This invention also provides a refrigeration system, including at least two refrigerant pumps as described above, wherein each refrigerant pump is connected in parallel; the liquid level pipes of each refrigerant pump are connected to each other; the liquid inlet pipes of each refrigerant pump are connected in parallel; and the discharge ends of each refrigerant pump are connected in parallel.

[0017] In some embodiments, the refrigeration system further includes a first heat exchanger, a throttling device, a second heat exchanger, and a second liquid receiver. A first end of the first heat exchanger is connected to the discharge end of each of the refrigerant pumps. A second end of the first heat exchanger is connected to the first end of the throttling device. A second end of the throttling device is connected to the first end of the second heat exchanger. A second end of the second heat exchanger is connected to the first end of the second liquid receiver. A second end of the second liquid receiver is connected to the inlet pipe of each of the refrigerant pumps.

[0018] In some embodiments, the first heat exchanger is an evaporator located indoors; the second heat exchanger is a condenser located outdoors.

[0019] The refrigerant pump and refrigeration system provided by this invention have the following advantages:

[0020] The refrigerant pump in this invention is equipped with a level pipe. In the refrigeration system, the level pipes of the refrigerant pumps connected in parallel are interconnected. When the refrigerant level is uneven in each of the first liquid receivers, the refrigerant at the high level will automatically flow to the refrigerant at the low level, thereby making the refrigerant level in each of the first liquid receivers uniform. The degassing pipe can degas the refrigerant entering the first liquid receiver through the level pipe, preventing cavitation inside the pump body and damage to the pump body. It can also stabilize the refrigerant flow rate drawn into the pump body, so as to make the system operate stably and improve the system's operational stability and efficiency. Attached Figure Description

[0021] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of a refrigerant pump provided in an embodiment of the present invention;

[0023] Figure 2 yes Figure 1 A magnified view of the area indicated by the circle;

[0024] Figure 3 yes Figure 1 A schematic diagram of the cylinder of a refrigerant pump;

[0025] Figure 4 This is a schematic diagram of a refrigerant pump provided in another embodiment of the present invention;

[0026] Figure 5 yes Figure 4 The diagram shows a cylinder of a refrigerant pump.

[0027] Figure 6 This is a schematic diagram of a refrigerant pump provided in another embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of a refrigeration system provided in an embodiment of the present invention.

[0029] Figure label:

[0030] 10 Pump body 24 Liquid level pipe

[0031] 11 cylinders, 25 degassing pipe

[0032] 111 blade slots 30 housing

[0033] 112 Spring Hole 31 Discharge End

[0034] 12 upper cylinder head 40 motor

[0035] 13 Lower cylinder head 41 Stator

[0036] 14 crankshafts and 42 rotors

[0037] 15 Rolling Rotor 50 First Heat Exchanger

[0038] 16-blade 60 second heat exchanger

[0039] 20 First reservoir 70 Second reservoir

[0040] 21 cylinder body 80 throttling device

[0041] 22 return pipe 91 first branch pipe

[0042] 23 Inlet pipe 92 Second branch pipe Detailed Implementation

[0043] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0044] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics represented in connection with that embodiment or example, which are included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics represented may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate different embodiments or examples represented in this application, as well as features of different embodiments or examples.

[0045] Furthermore, the terms "first" and "second" are used for illustrative purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the representation of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0046] To address the problems in the prior art, embodiments of the present invention provide a refrigerant pump. Figure 1 A schematic diagram of a refrigerant pump according to an embodiment of the present invention is shown. Figure 1 As shown, the refrigerant pump includes:

[0047] Pump body 10, including suction port;

[0048] The first liquid reservoir 20 includes a cylinder 21, a return pipe 22, an inlet pipe 23, a level pipe 24, and a degassing pipe 25. The return pipe 22 and the inlet pipe 23 are respectively located at the two ends of the cylinder 21 along the axial direction. The return pipe 22 is connected to the suction port. The first end of the level pipe 24 is located on the side wall of the cylinder 21. The degassing pipe 25 connects the inlet pipe 23 and the level pipe 24.

[0049] When multiple refrigerant pumps are connected in parallel, the liquid level pipes 24 of each refrigerant pump are connected. The connected liquid level pipes 24 act as U-shaped pipes. When the liquid refrigerant level in the first liquid receiver 20 of multiple refrigerant pumps is uneven, the liquid refrigerant with a higher liquid level will automatically flow to the one with a lower liquid level, so as to achieve a liquid equalization effect and ensure that the liquid refrigerant level in the first liquid receiver of each parallel refrigerant pump is uniform, and each refrigerant pump can operate stably.

[0050] Furthermore, the degassing pipe 25 connects the liquid inlet pipe 23 and the liquid level pipe 24. When the refrigerant is a gas-liquid mixture, the gaseous refrigerant is located above the liquid refrigerant. When the refrigerant passes through the liquid level pipe 24, the gaseous refrigerant is discharged through the degassing pipe 25, while the liquid refrigerant is drawn into the pump body 10 to participate in the working cycle. The discharge of gaseous refrigerant through the degassing pipe 25 can prevent gaseous refrigerant from entering the pump body 10 and causing cavitation, thus improving the working stability of the pump body 10. In addition, removing gaseous refrigerant through the degassing pipe 25 can also stabilize the refrigerant flow rate drawn into the pump body 10, enabling the refrigerant pump to operate stably and improving the working stability and efficiency of the refrigerant pump.

[0051] In this embodiment of the invention, the degassing pipe 25 is L-shaped, with one end connected to the liquid inlet pipe 23. The first end of the degassing pipe 25 is located on the side wall of the liquid inlet pipe 23, and the second end of the degassing pipe 25 is located on the side wall of the liquid level pipe 24.

[0052] Further, please refer to Figure 2The maximum diameter of the level tube 24 is D, and the diameter of the degassing tube 25 is d, satisfying: 1.4 < d / D < 0.32. For example, d / D can be 0.4, 0.6, 0.8, 1.0, or 1.2.

[0053] Further, please refer to Figure 1 The distance between the center of the liquid level tube 24 and the suction port is H, where H is greater than 30 mm. For example, H can be 40 mm, 45 mm, 50 mm, 55 mm, or 60 mm.

[0054] like Figure 7 As shown, the second ends of the liquid level pipes 24 of multiple refrigerant pumps connected in parallel are connected to each other through a pipeline, which includes a first branch pipe 91 and a second branch pipe 92. The first end of the first branch pipe 91 is connected to the second end of the liquid level pipe 24, and the second ends of multiple first branch pipes 91 are connected to the second branch pipes 92.

[0055] Furthermore, the second ends of the multiple first branch pipes 91 are located on the same horizontal plane, so that when the liquid refrigerant in the first liquid receiver 20 of the multiple refrigerant pumps is uneven in liquid level, the liquid refrigerant with a high liquid level will automatically flow to the liquid with a low liquid level, thereby achieving a liquid equalization effect.

[0056] Please see Figure 1 and Figure 3 The refrigerant pump also includes a housing 30 and a motor 40, with the pump body 10 and motor 40 located inside the housing 30. The pump body 10 includes a cylinder 11, an upper cylinder head 12, a lower cylinder head 13, a crankshaft 14, and a rolling rotor 15. The upper cylinder head 12 and lower cylinder head 13 are located at both ends of the cylinder 11, and the crankshaft 14 extends through both ends of the cylinder 11. The rolling rotor 15 is sleeved on the eccentric portion of the crankshaft 14 and located inside the cylinder 11. The motor 40 includes a stator 41 and a rotor 42 arranged coaxially with and inside the stator 41. The rotor 42 is connected to the crankshaft 14. When current is applied to the stator 41, the stator 41 generates a rotating magnetic field, which drives the rotor 42 to rotate, and the rotor 42 then drives the crankshaft 14 to rotate.

[0057] like Figure 3 As shown, the cylinder 11 includes a cylinder cavity. The cylinder 11 has a blade groove 111 communicating with the cylinder cavity and a spring hole 112 communicating with the blade groove 111 in the radial direction. A blade 16 is provided in the blade groove 111 and a spring is installed in the spring hole 112. The two ends of the blade 16 abut against the rolling rotor 15 and the spring, respectively.

[0058] In this embodiment of the invention, the pump body 10 has a double-cylinder single-suction structure, that is, the pump body 10 includes two cylinders 11 and a suction port, and the suction port is set on the intermediate plate between the two cylinders 11.

[0059] like Figure 4As shown, in some other embodiments, the pump body 10 can also be configured as a double-cylinder double-suction structure, that is, each of the two cylinders 11 is provided with a suction port. The specific structure of the cylinder 11 can be found in [reference needed]. Figure 5 As shown in the image.

[0060] like Figure 6 As shown, in some other embodiments, the pump body 10 can also be configured as a single-cylinder single-suction structure, that is, a single cylinder 11 has a suction port. The specific structure of the cylinder 11 can be found in [reference needed]. Figure 5 As shown in the image.

[0061] The working principle of a refrigerant pump is explained below.

[0062] When motor 40 operates, rotor 42 drives crankshaft 14 to rotate. Crankshaft 14 then drives rolling rotor 15 to roll along the inner wall of cylinder 11. The outer diameter of rolling rotor 15 and the inner diameter of cylinder 11 form a crescent-shaped working chamber. Blades 16, under the force of springs, ensure their ends are in close contact with rolling rotor 15, dividing the crescent-shaped working chamber into an intake chamber and a compression discharge chamber. Liquid refrigerant is drawn into an expanding chamber from return pipe 22. As the volume contracts, the refrigerant is propelled and gains a certain head, exiting pump body 10, i.e., entering the output pipe of the refrigeration system from discharge end 31 of casing 30. Head refers to the effective pressure head of the pump, i.e., the net increase in energy gained per unit mass of fluid passing through the pump.

[0063] The present invention also provides a refrigeration system, including at least two refrigerant pumps as described above, wherein the refrigerant pumps are connected in parallel; the liquid level pipes of each refrigerant pump are connected to each other; the liquid inlet pipes of each refrigerant pump are connected in parallel; and the discharge ends of each refrigerant pump are connected in parallel. Figure 7 A schematic diagram of a refrigeration system provided according to an embodiment of the present invention is shown. Figure 7 As shown, this embodiment of the invention provides a refrigeration system including three refrigerant pumps connected in parallel; the liquid level pipes 24 of each refrigerant pump are interconnected, the inlet pipes of each refrigerant pump are connected in parallel, and the discharge ends of each refrigerant pump are connected in parallel. The refrigeration system achieves all the technical effects of the aforementioned refrigerant pumps, which will not be elaborated further here.

[0064] The refrigeration system also includes a first heat exchanger 50, a throttling device 80, a second heat exchanger 60, and a second liquid receiver 70. The first end of the first heat exchanger 50 is connected to the discharge end 31 of each refrigerant pump, the second end of the first heat exchanger 50 is connected to the first end of the throttling device 80, the second end of the throttling device 80 is connected to the first end of the second heat exchanger 60, the second end of the second heat exchanger 60 is connected to the first end of the second liquid receiver 70, and the second end of the second liquid receiver 70 is connected to the inlet pipe 23 of each refrigerant pump.

[0065] The first heat exchanger 50 is an evaporator located indoors; the second heat exchanger 60 is a condenser located outdoors.

[0066] The working principle of the refrigeration system is explained below.

[0067] After absorbing heat and evaporating in the first heat exchanger 50 (evaporator) located indoors, the liquid refrigerant enters the second heat exchanger 60 (condenser) outdoors and condenses into subcooled liquid refrigerant. It then enters the second liquid receiver 70 for oil-liquid separation before returning to the first liquid receiver 20. The refrigerant is then pumped back to the evaporator by the refrigerant pump, completing one working cycle. The parallel connection of the refrigerant pumps increases both the head and flow rate. In practical applications, those skilled in the art can select the number of refrigerant pumps connected in parallel based on the installation distance, head, and cooling load requirements of the indoor and outdoor unit systems; no specific limitations are imposed here.

[0068] In summary, the refrigerant pump and refrigeration system provided by this invention have the following advantages:

[0069] The refrigerant pump in this invention is equipped with a level pipe. In the refrigeration system, the level pipes of the refrigerant pumps connected in parallel are interconnected. When the refrigerant level inside each first liquid receiver is uneven, the refrigerant at the high level will automatically flow to the low level, thereby making the refrigerant level inside each first liquid receiver uniform. The degassing pipe can degas the gaseous refrigerant passing through the level pipe, thereby preventing the pump body from drawing in gaseous refrigerant, preventing cavitation inside the pump body, damaging the pump body, and stabilizing the refrigerant flow rate drawn into the pump body, so that the system operates stably and improves the system's operational stability and efficiency.

[0070] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A refrigerant pump characterized by, The application relates to a refrigerant pump. The pump body comprises a suction port. The first liquid reservoir comprises a cylinder, a liquid return pipe, a liquid inlet pipe, a liquid level pipe and a degassing pipe; the liquid return pipe and the liquid inlet pipe are arranged at the axial two ends of the cylinder; the liquid return pipe is connected with the suction port; the first end of the liquid level pipe is arranged on the side wall of the cylinder; the degassing pipe is connected with the liquid inlet pipe and the liquid level pipe.

2. The refrigerant pump of claim 1, wherein, The first end of the degassing pipe is arranged on the side wall of the liquid inlet pipe, and the second end of the degassing pipe is arranged on the side wall of the liquid level pipe.

3. The refrigerant pump of claim 1, wherein, The maximum diameter of the liquid level pipe is D, and the diameter of the degassing pipe is d, and the following condition is met: 0.32 < d / D < 1.

4.

4. The refrigerant pump of claim 1, wherein, The distance between the center of the liquid level pipe and the suction port is H, and H is greater than 30 mm.

5. The refrigerant pump of claim 1, wherein, The second ends of the liquid level pipes of a plurality of refrigerant pumps connected in parallel are connected with each other through pipelines, the pipelines comprise first sub-pipes and a second sub-pipe, the first ends of the first sub-pipes are connected with the second ends of the liquid level pipes, and the second ends of the first sub-pipes are connected with the second sub-pipe.

6. The refrigerant pump of claim 5, wherein, The second ends of the first sub-pipes are located on the same horizontal plane.

7. The refrigerant pump of any of claims 1-6, wherein, The refrigerant pump further comprises a shell and a motor, the pump body and the motor are located in the shell; the pump body comprises a cylinder, an upper cylinder cover, a lower cylinder cover, a crankshaft and a rolling rotor; the upper cylinder cover and the lower cylinder cover are located at the axial two ends of the cylinder; the crankshaft penetrates through the two ends of the cylinder; the rolling rotor is sleeved on the eccentric part of the crankshaft and located in the cylinder; the motor comprises a stator and a rotor coaxially arranged with the stator, and the rotor is connected with the crankshaft.

8. A refrigeration system characterized by, The refrigerant system comprises at least two refrigerant pumps as claimed in claim 7, the refrigerant pumps are connected in parallel; the liquid level pipes of the refrigerant pumps are connected with each other, the liquid inlet pipes of the refrigerant pumps are connected in parallel, and the discharge ends of the refrigerant pumps are connected in parallel.

9. The refrigeration system of claim 8, wherein, The refrigerant system further comprises a first heat exchanger, a throttling device, a second heat exchanger and a second liquid reservoir; the first end of the first heat exchanger is connected with the discharge ends of the refrigerant pumps; the second end of the first heat exchanger is connected with the first end of the throttling device; the second end of the throttling device is connected with the first end of the second heat exchanger; the second end of the second heat exchanger is connected with the first end of the second liquid reservoir; and the second end of the second liquid reservoir is connected with the liquid inlet pipes of the refrigerant pumps.

10. The refrigeration system of claim 9, wherein, The first heat exchanger is an evaporator and is located indoors; and the second heat exchanger is a condenser and is located outdoors.

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