A dual-motor compressor and refrigeration system

Abstract

The utility model relates to a kind of double-motor compressor and refrigeration system, double-motor compressor includes compressor shell, auxiliary bearing, first motor, second motor, pump body structure, crankshaft, the auxiliary bearing, first motor, second motor, pump body structure are respectively spaced in the inside of the compressor shell, the crankshaft is worn in the auxiliary bearing, first motor, second motor and pump body structure, the auxiliary bearing is opened with multiple first through holes along the axial direction penetration, the double-motor compressor of the utility model, by the combination of first motor and second motor, can expand compressor operating speed upper limit range, realize the effect that compressor is in higher operating interval.

Description

Technical Field

[0001] This utility model relates to the field of compressor technology, and in particular to a dual-motor compressor and refrigeration system. Background Technology

[0002] With the development of refrigeration technology, the industry has become increasingly stringent in its requirements regarding the greenhouse effect and ozone depletion effect of refrigerants, as well as their coefficient of performance (COP). For example, refrigerants such as R134yf, R290, and R32 are widely used in refrigeration systems across various scenarios. Due to the differences in physical properties between different refrigerants, their saturation pressures at the same saturation temperature differ, resulting in different load ranges driven by the motors. The magnitude of the refrigerant compression load directly affects the motor efficiency, and consequently, the compressor's energy efficiency. Currently, most common compressors use a single pump structure with a single motor. When using different types of refrigerants with the same displacement design, this single-motor compressor typically requires a motor specifically matched to the load to ensure the compressor's energy efficiency meets requirements, leading to low compressor versatility. Furthermore, when developing new refrigerants, especially when transitioning from low-load to high-load refrigerants, such as switching from low-pressure R134a to medium-pressure R290, under the same operating conditions, when the discharge pressure increases by 30%, the electromagnetic torque of the motor must also increase by about 30%. For models in the same series, especially asynchronous AC motors, it is difficult to increase the upper limit of the motor's electromagnetic torque, which will lead to a significant deterioration in motor efficiency. In order to ensure energy efficiency requirements, the maximum displacement of the compressor can only be reduced by 30%, which will result in a reduction in the compressor's cooling capacity. Utility Model Content

[0003] Based on this, the purpose of this utility model is to overcome the shortcomings of the prior art and provide a dual-motor compressor and refrigeration system. By combining the first motor and the second motor, the upper limit range of the compressor's operating speed can be expanded, so that the compressor can operate in a higher range.

[0004] To achieve the above objectives, the first aspect of this utility model provides a dual-motor compressor, including a compressor housing, an auxiliary bearing, a first motor, a second motor, a pump body structure, and a crankshaft. The auxiliary bearing, the first motor, the second motor, and the pump body structure are respectively spaced apart inside the compressor housing. The crankshaft passes through the auxiliary bearing, the first motor, the second motor, and the pump body structure. The auxiliary bearing has a plurality of first through holes extending through it in the axial direction.

[0005] Therefore, the dual-motor compressor according to this utility model embodiment, by setting a first motor and a second motor inside the compressor housing, and by setting an auxiliary bearing inside the compressor housing, so that the extended crankshaft can pass through the auxiliary bearing, the first motor, the second motor, and the pump body structure, effectively improves the rigidity of the pump body structure. At the same time, by opening multiple first through holes on the auxiliary bearing, so that the refrigerant can pass through and the wires can pass through. Furthermore, by combining the first motor and the second motor, this utility model embodiment can expand the upper limit range of the compressor's operating speed, so that the compressor can operate in a higher range.

[0006] In one embodiment, the first motor is located above the second motor, a first terminal is provided on the top of the compressor housing, the first terminal is connected to the first motor through a first wire, and a second terminal is provided on the side wall of the compressor housing, the second terminal is connected to the second motor through a second wire.

[0007] In one embodiment, the inner diameter of the first through hole is larger than the outer diameter of the first wire. A portion of the first terminal extends into the interior of the compressor housing, and a portion of the first terminal extends out of the compressor housing. One end of the first wire is electrically connected to the first motor, and the other end of the first wire is electrically connected to the portion of the first terminal extending into the compressor housing. A portion of the second terminal extends into the interior of the compressor housing, and a portion of the second terminal extends out of the compressor housing. One end of the second wire is electrically connected to the second motor, and the other end of the second wire is electrically connected to the portion of the second terminal extending into the compressor housing.

[0008] In one embodiment, the pump body structure is located between the first motor and the second motor, or the pump body structure is located below the second motor.

[0009] In one embodiment, a liquid reservoir is provided on the outer wall of the compressor housing, and the liquid reservoir is connected to the pump body structure.

[0010] In one embodiment, the auxiliary bearing is located at the upper or lower end of the crankshaft.

[0011] As one embodiment, it also includes a main bearing, which and the auxiliary bearing are respectively disposed at both ends of the crankshaft, and the main bearing has a plurality of second through holes extending through it in the axial direction.

[0012] In one implementation, both the first motor and the second motor are asynchronous AC motors, or both the first motor and the second motor are synchronous brushless DC motors.

[0013] As one implementation, the system also includes a controller, which is electrically connected to both the first motor and the second motor.

[0014] A second aspect of this utility model provides a refrigeration system comprising a dual-motor compressor as described in any of the preceding embodiments. According to this utility model embodiment, the refrigeration system, through the combination of a first motor and a second motor, can expand the upper limit range of the compressor's operating speed, achieving the effect of the compressor operating in a higher range.

[0015] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is one of the cross-sectional schematic diagrams of the dual-motor compressor according to an embodiment of the present utility model;

[0017] Figure 2 This is a second cross-sectional schematic diagram of the dual-motor compressor according to an embodiment of the present utility model;

[0018] Figure 3 This is a schematic diagram of the auxiliary bearing of the dual-motor compressor according to an embodiment of the present invention;

[0019] Figure 4 for Figure 3 The diagram shows a cross-sectional view along direction AA.

[0020] Explanation of reference numerals in the attached drawings: 10, compressor housing; 20, auxiliary bearing; 21, first through hole; 30, first motor; 31, first terminal; 32, first wire; 40, second motor; 41, second terminal; 42, second wire; 50, pump body structure; 60, liquid reservoir; 70, main bearing; 80, crankshaft. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are merely 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.

[0022] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0023] In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims. In the description of this application, it should be understood that the terms "first," "second," "third," etc., are used only to distinguish similar objects and are not necessarily used to describe a specific order or sequence, nor should they be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In related technologies, with the development of refrigeration technology, the industry has increasingly stringent requirements regarding the greenhouse effect and ozone depletion effect of refrigerants, as well as their coefficient of performance (COP). For example, refrigerants such as R134yf, R290, and R32 are widely used in refrigeration systems across various scenarios. Due to the differences in physical properties between different refrigerants, the saturation pressure corresponding to the same saturation temperature varies, resulting in different load ranges driven by the motor. The magnitude of the refrigerant compression load directly affects the motor efficiency, and consequently, the compressor's energy efficiency. Currently, most common compressors use a single pump structure with a single motor. When using different types of refrigerants with the same displacement design, this type of single-motor compressor typically requires a motor specifically matched to the corresponding load to ensure that the compressor's energy efficiency meets requirements, leading to low compressor versatility. Furthermore, when developing new refrigerants, especially when transitioning from low-load to high-load refrigerants, such as switching from low-pressure R134a to medium-pressure R290, under the same operating conditions, when the discharge pressure increases by 30%, the electromagnetic torque of the motor must also increase by about 30%. For models in the same series, especially asynchronous AC motors, it is difficult to increase the upper limit of the motor's electromagnetic torque, which will lead to a significant deterioration in motor efficiency. In order to ensure energy efficiency requirements, the maximum displacement of the compressor can only be reduced by 30%, which will result in a reduction in the compressor's cooling capacity.

[0025] Therefore, this utility model embodiment provides a dual-motor compressor and refrigeration system. According to this utility model embodiment, the dual-motor compressor and refrigeration system, through the combination of the first motor 30 and the second motor 40, can expand the upper limit range of the compressor's operating speed, achieving the effect of the compressor operating in a higher range.

[0026] Please see Figures 1 to 4 The first aspect of this utility model provides a dual-motor compressor, including a compressor housing 10, an auxiliary bearing 20, a first motor 30, a second motor 40, a pump body structure 50, and a crankshaft 80. The auxiliary bearing 20, the first motor 30, the second motor 40, and the pump body structure 50 are respectively spaced apart inside the compressor housing 10. The crankshaft 80 passes through the auxiliary bearing 20, the first motor 30, the second motor 40, and the pump body structure 50. The auxiliary bearing 20 has multiple first through holes 21 extending along the axial direction. Further, this utility model embodiment also includes a controller, which is electrically connected to the first motor 30 and the second motor 40 via wires. The controller in this utility model embodiment is a conventional controller in the art, and will not be described in detail here. In addition, a liquid reservoir 60 is provided on the outer wall of the compressor housing 10 in this utility model embodiment, and the liquid reservoir 60 is connected to the pump body structure 50.

[0027] Therefore, the dual-motor compressor according to this utility model embodiment, by setting a first motor 30 and a second motor 40 inside the compressor housing 10, and by setting an auxiliary bearing 20 inside the compressor housing 10, so that the extended crankshaft 80 can pass through the auxiliary bearing 20, the first motor 30, the second motor 40, and the pump body structure 50, effectively improves the rigidity of the pump body structure 50. At the same time, by opening multiple first through holes 21 on the auxiliary bearing 20, so that the refrigerant can pass through and the wires can pass through. Furthermore, by combining the first motor 30 and the second motor 40, this utility model embodiment can expand the upper limit range of the compressor's operating speed, so as to achieve the effect of the compressor operating in a higher range.

[0028] Optionally, in some embodiments of this utility model, the auxiliary bearing 20 is disposed at the upper or lower end of the crankshaft 80. This can be understood as follows: when the auxiliary bearing 20 is disposed at the upper end of the crankshaft 80, the multiple first through holes 21 on the auxiliary crankshaft can not only allow refrigerant to pass through, but also allow wires to pass through, so that the wiring of the first motor 30 or the second motor 40 is more rationally arranged. It is worth noting that in other embodiments, the dual-motor compressor also includes a main bearing 70, which, along with the auxiliary bearing 20, is disposed at both ends of the crankshaft 80. The main bearing 70 has multiple second through holes extending through it in the axial direction; that is, the main bearing 70 and the auxiliary bearing 20 have essentially the same structure and are disposed at both ends of the crankshaft 80.

[0029] Optionally, in some embodiments of the present invention, the first motor 30 is located above the second motor 40, the top of the compressor housing 10 is provided with a first terminal 31, the first terminal 31 is connected to the first motor 30 through a first wire 32, the side wall of the compressor housing 10 is provided with a second terminal 41, the second terminal 41 is connected to the second motor 40 through a second wire 42. Furthermore, in these embodiments, the inner diameter of the first through hole 21 is larger than the outer diameter of the first wire 32. A portion of the first terminal 31 extends into the interior of the compressor housing 10, and a portion of the first terminal 31 extends out of the compressor housing 10. One end of the first wire 32 is electrically connected to the first motor 30, and the other end of the first wire 32 passes through one of the first through holes 21 and is electrically connected to the portion of the first terminal 31 that extends into the compressor housing 10. A portion of the second terminal 41 extends into the interior of the compressor housing 10, and a portion of the second terminal 41 extends out of the compressor housing 10. One end of the second wire 42 is electrically connected to the second motor 40, and the other end of the second wire 42 is electrically connected to the portion of the second terminal 41 that extends into the compressor housing 10.

[0030] Optionally, in some embodiments of the present invention, the pump body structure 50 is located between the first motor 30 and the second motor 40, or the pump body structure 50 is located below the second motor 40.

[0031] Optionally, in some embodiments of this utility model, the first motor 30 and the second motor 40 are both asynchronous AC motors, or the first motor 30 and the second motor 40 are both synchronous brushless DC motors.

[0032] The following is combined with Figure 1 , Figure 3 and Figure 4 The following is a detailed description of a specific embodiment of the dual-motor compressor according to the present invention. It is worth understanding that the following description is merely exemplary and should not be construed as limiting the present invention.

[0033] This embodiment provides a dual-motor compressor, including a compressor housing 10, an auxiliary bearing 20, a first motor 30, a second motor 40, a pump body structure 50, a crankshaft 80, a liquid reservoir 60, and a controller. The auxiliary bearing 20, the first motor 30, the second motor 40, and the pump body structure 50 are arranged sequentially from top to bottom within the compressor housing 10. The crankshaft 80 passes through the auxiliary bearing 20, the first motor 30, the second motor 40, and the pump body structure 50. The auxiliary bearing 20 has multiple first through holes 21 extending axially. The liquid reservoir 60 is disposed on the outer side wall of the compressor housing 10 and is connected to the pump body structure 50. Further, a first terminal 31 is provided on the top of the compressor housing 10, and the first terminal 31 is connected to the first motor 30 via a first wire 32. A second terminal 41 is provided on the side wall of the compressor housing 10, and the second terminal 41 is connected to the second motor 40 via a second wire 42. The inner diameter of the first through hole 21 is larger than the outer diameter of the first wire 32. A portion of the first terminal 31 extends into the compressor housing 10, and a portion of the first terminal 31 extends out of the compressor housing 10. One end of the first wire 32 is electrically connected to the first motor 30, and the other end of the first wire 32 passes through one of the first through holes 21 and is electrically connected to the portion of the first terminal 31 that extends into the compressor housing 10. A portion of the second terminal 41 extends into the compressor housing 10, and a portion of the second terminal 41 extends out of the compressor housing 10. One end of the second wire 42 is electrically connected to the second motor 40, and the other end of the second wire 42 is electrically connected to the portion of the second terminal 41 that extends into the compressor housing 10. In addition, the controller is electrically connected to the portions of the first terminal 31 and the second terminal 41 that extend out of the compressor housing 10 via wires.

[0034] In this embodiment, both the first motor 30 and the second motor 40 are asynchronous AC motors, and the controller can independently control the start and stop of the first motor 30 and the second motor 40. The operating current of the first motor 30 is denoted as I1, the stall current of the first motor 30 is denoted as Is1, the operating current of the first motor 30 is denoted as I2, and the stall current of the first motor 30 is denoted as Is2. During the operation of the dual-motor compressor in this embodiment, the controller controls the first motor 30 to always be in the running state and controls the second motor 40 to be in the off state by default. When the refrigeration system detects that the operating current I1 of the first motor 30 is greater than X*Is1 (X is the current overload coefficient, set at 0.3≤X≤1), it determines that the dual-motor compressor is in the overload low-efficiency operating range. The controller starts the second motor 40 to provide auxiliary power to divert the load of the first motor 30, so that the first motor 30 returns to the high-efficiency operating range. When the refrigeration system detects that the operating current I1 of the first motor 30 satisfies the relationship 0≤I1≤X*Is1, it determines that the dual-motor compressor has returned to the high-efficiency operating state. The controller shuts down the second motor 40, and only the normal operation of the first motor 30 needs to be maintained. Therefore, this embodiment, through the combination of the first motor 30 and the second motor 40, can achieve the effect of the dual-motor compressor operating in a higher range, so that the energy efficiency of the dual-motor compressor meets the preset requirements.

[0035] The following is combined with Figure 2 , Figure 3 and Figure 4 The following is a detailed description of a specific embodiment of the dual-motor compressor according to the present invention. It is worth understanding that the following description is merely exemplary and should not be construed as limiting the present invention.

[0036] This embodiment provides a dual-motor compressor, including a compressor housing 10, an auxiliary bearing 20, a first motor 30, a pump body structure 50, a second motor 40, a main bearing 70, a crankshaft 80, a liquid receiver 60, and a controller. The auxiliary bearing 20, the first motor 30, the pump body structure 50, the second motor 40, and the main bearing 70 are arranged sequentially from top to bottom inside the compressor housing 10. The crankshaft 80 passes through the auxiliary bearing 20, the first motor 30, the pump body structure 50, the second motor 40, and the main bearing 70. The auxiliary bearing 20 has multiple first through holes 21 extending along the axial direction, and the main bearing 70 has multiple second through holes extending along the axial direction. The liquid receiver 60 is disposed on the outer wall of the compressor housing 10 and is connected to the pump body structure 50. Furthermore, a first terminal 31 is provided on the top of the compressor housing 10, and the first terminal 31 is connected to the first motor 30 through a first wire 32. A second terminal 41 is provided on the side wall of the compressor housing 10, and the second terminal 41 is connected to the second motor 40 through a second wire 42. The inner diameter of the first through hole 21 is larger than the outer diameter of the first wire 32. A portion of the first terminal 31 extends into the compressor housing 10, and a portion of the first terminal 31 extends out of the compressor housing 10. One end of the first wire 32 is electrically connected to the first motor 30, and the other end of the first wire 32 passes through one of the first through holes 21 and is electrically connected to the portion of the first terminal 31 that extends into the compressor housing 10. A portion of the second terminal 41 extends into the compressor housing 10, and a portion of the second terminal 41 extends out of the compressor housing 10. One end of the second wire 42 is electrically connected to the second motor 40, and the other end of the second wire 42 is electrically connected to the portion of the second terminal 41 that extends into the compressor housing 10. In addition, the controller is electrically connected to the portions of the first terminal 31 and the second terminal 41 that extend out of the compressor housing 10 via wires.

[0037] In this embodiment, both the first motor 30 and the second motor 40 are synchronous brushless DC motors, and the controller can independently control the start and stop of the first motor 30 and the second motor 40. The first motor 30 is designed as a high-efficiency motor with a relatively small speed range, while the second motor 40 is designed as a high-speed motor with relatively low efficiency. When the dual-motor compressor is running normally, if the refrigeration system detects that the operating power P of the dual-motor compressor is less than or equal to the maximum rated power Pmax, the controller controls the first motor 30 to run normally, while the second motor 40 is disconnected, ensuring priority is given to the operating efficiency of the dual-motor compressor. When the dual-motor compressor is in a special environment such as a high-temperature environment, if the refrigeration system detects that the operating power P of the dual-motor compressor is greater than the maximum rated power Pmax, the controller shuts down the first motor 30 and starts the second motor 40, thereby expanding the upper limit range of the operating speed of the dual-motor compressor and ensuring priority is given to cooling capacity.

[0038] A second aspect of this utility model provides a refrigeration system including a dual-motor compressor as described above. According to this utility model embodiment, the refrigeration system, through the combination of the first motor 30 and the second motor 40, can expand the upper limit range of the compressor's operating speed, achieving the effect of the compressor operating in a higher range.

[0039] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the dual-motor compressor and refrigeration system of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model.

Claims

1. A dual-motor compressor, characterized in that: The compressor includes a compressor housing, an auxiliary bearing, a first motor, a second motor, a pump body structure, and a crankshaft. The auxiliary bearing, the first motor, the second motor, and the pump body structure are respectively spaced apart inside the compressor housing. The crankshaft passes through the auxiliary bearing, the first motor, the second motor, and the pump body structure. The auxiliary bearing has multiple first through holes extending through it in the axial direction.

2. The dual-motor compressor according to claim 1, characterized in that: The first motor is located above the second motor. A first terminal is provided on the top of the compressor housing. The first terminal is connected to the first motor via a first wire. A second terminal is provided on the side wall of the compressor housing. The second terminal is connected to the second motor via a second wire.

3. The dual-motor compressor according to claim 2, characterized in that: The inner diameter of the first through hole is larger than the outer diameter of the first wire. A portion of the first terminal extends into the interior of the compressor housing, and a portion of the first terminal extends out of the compressor housing. One end of the first wire is electrically connected to the first motor, and the other end of the first wire is electrically connected to the portion of the first terminal that extends into the compressor housing. A portion of the second terminal extends into the interior of the compressor housing, and a portion of the second terminal extends out of the compressor housing. One end of the second wire is electrically connected to the second motor, and the other end of the second wire is electrically connected to the portion of the second terminal that extends into the compressor housing.

4. The dual-motor compressor according to claim 2, characterized in that: The pump body structure is located between the first motor and the second motor, or the pump body structure is located below the second motor.

5. The dual-motor compressor according to claim 1, characterized in that: A liquid reservoir is provided on the outer wall of the compressor housing, and the liquid reservoir is connected to the pump body structure.

6. The dual-motor compressor according to claim 1, characterized in that: The auxiliary bearing is located at the upper or lower end of the crankshaft.

7. The dual-motor compressor according to claim 1, characterized in that: It also includes a main bearing, which and the auxiliary bearing are respectively located at both ends of the crankshaft, and the main bearing has multiple second through holes extending through it in the axial direction.

8. The dual-motor compressor according to claim 1, characterized in that: Both the first motor and the second motor are asynchronous AC motors, or both the first motor and the second motor are synchronous brushless DC motors.

9. The dual-motor compressor according to claim 1, characterized in that: It also includes a controller, which is electrically connected to the first motor and the second motor respectively.

10. A refrigeration system, characterized in that: Including the dual-motor compressor according to any one of claims 1 to 9.

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