Parallel compressor oil balancing device and air conditioning system

Abstract

The utility model relates to the technical field of compressors, in particular to a parallel compressor oil balancing device and an air conditioning system. The parallel compressor oil balancing device comprises a first compressor, a second compressor, an air suction pipeline, an oil balancing pipe, a pressure guiding pipe and a control valve, the air suction pipeline comprises an air suction main pipe, a first air suction branch pipe and a second air suction branch pipe, and the first air suction branch pipe is communicated with an air suction port of the first compressor; the second air suction branch pipe communicates with an air suction port of the second compressor. The two ends of the oil balancing pipe are communicated with an oil pool of the first compressor and an oil pool of the second compressor respectively, one end of the pressure guiding pipe is communicated with the oil balancing pipe, and the other end of the pressure guiding pipe is communicated with the air suction main pipe. According to the parallel compressor oil balance device and the air conditioning system, the problem that the oil level of an existing parallel compressor system is unbalanced when part of the compressors operate is solved.

Description

Technical Field

[0001] The present application relates to the technical field of compressors, and in particular to an oil balancing device for parallel compressors and an air-conditioning system. Background Art

[0002] Parallel compressors are increasingly being used in the refrigeration industry due to their advantages, including convenient energy regulation, low cost, and high part-load energy efficiency. Compressors rely on lubricating oil for operation, and during this process, some oil is forced out of the compressor's exhaust port. Furthermore, in a multi-compressor system, individual compressors may experience differences in operating pressure and state. Consequently, long-term operation can lead to an imbalance in oil levels between compressors. This can cause some compressors to be short of oil, leading to bearing burns, while others may have excessive oil levels, resulting in increased power consumption. Therefore, when paralleling compressors, it is crucial to address the issue of lubricating oil balance between compressors.

[0003] In the prior art, the common method for solving the oil balance problem between compressors is to simply connect an oil balancing pipe between the oil sumps of the two compressors, treating the oil sump and the oil balancing pipe as a single connecting vessel to balance the oil levels in the sump. However, when the parallel compressors are partially unloaded, the internal pressure of the operating compressor will be lower than that of the inoperative compressor. This can cause the lubricating oil in the inoperative compressor to enter the operating compressor through the oil balancing pipe. In severe cases, this can lead to a significant difference in the oil levels between the two compressors, affecting the normal operation of the compressors. Utility Model Content

[0004] Based on this, it is necessary to provide a parallel compressor oil balancing device and an air conditioning system to solve the problem of oil level imbalance in the existing parallel compressor system when some compressors are running.

[0005] The present application provides an oil balancing device for parallel compressors, which includes a first compressor, a second compressor, an intake pipeline, an oil balancing pipe, a pressure pipe and a control valve. The intake pipeline includes an intake main pipe and a first intake branch pipe and a second intake branch pipe connected to the intake main pipe. The first intake branch pipe is connected to the intake port of the first compressor, and the second intake branch pipe is connected to the intake port of the second compressor; the two ends of the oil balancing pipe are respectively connected to the oil pool of the first compressor and the oil pool of the second compressor, one end of the pressure pipe is connected to the oil balancing pipe, and the other end is connected to the intake main pipe, wherein the control valve is arranged on the pressure pipe for controlling the on and off of the pressure pipe.

[0006] In one embodiment, the oil balancing pipe is provided with a first bending section and a second bending section, the first bending section is arranged close to the first compressor, and the second bending section is arranged close to the second compressor, and the first bending section is not higher than the first connection point where the oil balancing pipe is connected to the oil pool of the first compressor, and the second bending section is not higher than the second connection point where the oil balancing pipe is connected to the oil pool of the second compressor, and the first connection point and the second connection point are located at the same horizontal position; wherein, the connection between the pressure-drawing pipe and the oil balancing pipe is arranged between the first bending section and the second bending section.

[0007] In one embodiment, the first bending section and the second bending section are both V-shaped.

[0008] In one embodiment, a gas-liquid separator is provided on the air suction main pipe, and the air suction main pipe includes a first pipe section and a second pipe section, the first pipe section is connected to the inlet of the gas-liquid separator, and the second pipe section is connected to the outlet of the gas-liquid separator; wherein, the second pipe section is connected to the first air suction branch pipe and the second air suction branch pipe.

[0009] In one embodiment, the connection between the pressure-inducing pipe and the main suction pipe is located on the first pipe section.

[0010] In one embodiment, the connection between the pressure-inducing pipe and the main suction pipe is located on the second pipe section.

[0011] In one embodiment, the length of the first air suction branch pipe is equal to the length of the second air suction branch pipe; the inner diameter of the first air suction branch pipe is equal to the inner diameter of the second air suction branch pipe.

[0012] In one embodiment, the control valve is configured as a solenoid valve or an electric ball valve.

[0013] In one embodiment, the parallel compressor oil balancing device also includes an exhaust pipeline, which includes an exhaust main pipe and a first exhaust branch pipe and a second exhaust branch pipe connected to the exhaust main pipe. The first exhaust branch pipe and the second exhaust branch pipe are arranged in parallel. The first exhaust branch pipe is connected to the exhaust port of the first compressor, and the second exhaust branch pipe is connected to the exhaust port of the second compressor.

[0014] The present application also provides an air-conditioning system, which includes the parallel compressor oil balancing device described in any one of the above embodiments.

[0015] Compared with the prior art, the parallel compressor oil balancing device and air-conditioning system provided by the present application, by setting a pressure-guiding pipe and a control valve on the pressure-guiding pipe, when the first compressor and the second compressor are both in operation, the pressure-guiding pipe is cut off by closing the control valve. At this time, the first compressor and the second compressor can achieve oil balance by using the oil equalizing pipe. When the first compressor and the second compressor are opened and closed, the pressure-guiding pipe is connected by opening the control valve. At this time, the pressure at the connection between the pressure-guiding pipe and the oil equalizing pipe is basically equivalent to the pressure at the suction main pipe, which is greater than the pressure inside the first compressor and the second compressor. Therefore, the lubricating oil in the non-operating compressor of the first compressor and the second compressor will not flow to the operating compressor through the oil equalizing pipe, thereby achieving oil level balance and ensuring that the parallel compressor oil balancing device can operate safely. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is a schematic structural diagram of an oil balancing device for parallel compressors according to an embodiment of the present application.

[0018] The symbols in the figure mean the following:

[0019] 100. Oil balancing device for parallel compressors; 10. First compressor; 20. Second compressor; 30. Oil balancing pipe; 31. First bending section; 32. Second bending section; 40. Pressure-guiding pipe; 50. Control valve; 60. Intake pipe; 61. Intake main pipe; 611. First pipe section; 612. Second pipe section; 62. First intake branch pipe; 63. Second intake branch pipe; 64. Gas-liquid separator; 70. Exhaust pipe; 71. Exhaust main pipe; 72. First exhaust branch pipe; 73. Second exhaust branch pipe. DETAILED DESCRIPTION

[0020] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0021] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the specification of this application are for illustrative purposes only and do not represent the only implementation method.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0023] In this application, unless otherwise expressly specified or limited, a first feature being “above” or “below” a second feature may mean that the first feature is directly in contact with the second feature, or that the first feature and the second feature are indirectly in contact through an intermediate medium. Furthermore, a first feature being “above,” “above,” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below,” “below,” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0024] Unless otherwise defined, all technical and scientific terms used in the specification of this application have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in the specification of this application includes any and all combinations of one or more of the relevant listed items.

[0025] Parallel compressors are increasingly being used in the refrigeration industry due to their advantages, including convenient energy regulation, low cost, and high part-load energy efficiency. Compressors rely on lubricating oil for operation, and during this process, some oil is forced out of the compressor's exhaust port. Furthermore, in a multi-compressor system, individual compressors may experience differences in operating pressure and state. Consequently, long-term operation can lead to an imbalance in oil levels between compressors. This can cause some compressors to be short of oil, leading to bearing burns, while others may have excessive oil levels, resulting in increased power consumption. Therefore, when paralleling compressors, it is crucial to address the issue of lubricating oil balance between compressors.

[0026] In the prior art, the common method for solving the oil balance problem between compressors is to simply connect an oil balancing pipe between the oil sumps of the two compressors, treating the oil sump and the oil balancing pipe as a single connecting vessel to balance the oil levels in the sump. However, when the parallel compressors are partially unloaded, the internal pressure of the operating compressor will be lower than that of the inoperative compressor. This can cause the lubricating oil in the inoperative compressor to enter the operating compressor through the oil balancing pipe. In severe cases, this can lead to a significant difference in the oil levels between the two compressors, affecting the normal operation of the compressors.

[0027] See also Figure 1 In order to solve the problem of oil level imbalance in the existing parallel compressor system when some compressors are running, the present application provides a parallel compressor oil balancing device 100, which includes a first compressor 10, a second compressor 20, an intake pipe 60, an oil balancing pipe 30, a pressure pipe 40, and a control valve 50. The intake pipe 60 includes an intake main pipe 61 and a first intake branch pipe 62 and a second intake branch pipe 63 connected to the intake main pipe 61. The first intake branch pipe 62 is connected to the intake port of the first compressor 10, and the second intake branch pipe 63 is connected to the intake port of the second compressor 20. The two ends of the oil balancing pipe 30 are respectively connected to the oil pool of the first compressor 10 and the oil pool of the second compressor 20. One end of the pressure pipe 40 is connected to the oil balancing pipe 30, and the other end is connected to the intake main pipe 61. The control valve 50 is provided on the pressure pipe 40 to control the on and off of the pressure pipe 40.

[0028] It is understandable that the present application sets a pressure-inducing pipe 40 and sets a control valve 50 on the pressure-inducing pipe 40. When the first compressor 10 and the second compressor 20 are both in operation, the pressure-inducing pipe 40 is cut off by closing the control valve 50. At this time, the first compressor 10 and the second compressor 20 can achieve oil balance by using the oil equalizing pipe 30. When the first compressor 10 and the second compressor 20 are opened and closed, the pressure-inducing pipe 40 is connected by opening the control valve 50. At this time, the pressure at the connection between the pressure-inducing pipe 40 and the oil equalizing pipe 30 is basically equivalent to the pressure at the suction main pipe 61, which is greater than the pressure inside the first compressor 10 and the second compressor 20. Therefore, the lubricating oil in the non-operating compressor of the first compressor 10 and the second compressor 20 will not flow into the operating compressor through the oil equalizing pipe 30, thereby achieving oil level balance and ensuring that the parallel compressor oil balancing device 100 can operate safely.

[0029] In summary, the parallel compressor oil balancing device 100 of the present application can ensure that the oil level in the oil pool is at an appropriate position when operating at full load or partially unloading the load, thereby greatly improving the reliability of the operation of the parallel compressor oil balancing device 100, and preventing the compressor from burning due to lack of oil, or causing temperature rise and increased power consumption due to excessive oil.

[0030] It should be noted that full load operation of the parallel compressor oil balancing device 100 means that both the first compressor 10 and the second compressor 20 are in operation, and partial unloading load means that only one of the first compressor 10 and the second compressor 20 is still in operation, while the other is in a non-operating state.

[0031] It should also be noted that the number of compressors in the parallel compressor oil balancing device 100 is not limited to two, and can also be set to three, four or more, and can be reasonably set according to actual needs.

[0032] Furthermore, in one embodiment, the control valve 50 is configured as a solenoid valve or an electric ball valve, which can achieve automatic control through electric control, thereby improving response speed and reliability.

[0033] In one embodiment, if Figure 1 As shown, the oil balancing pipe 30 is provided with a first bend section 31 and a second bend section 32. The first bend section 31 is located near the first compressor 10, and the second bend section 32 is located near the second compressor 20. Furthermore, the first bend section 31 is no higher than the first connection point between the oil balancing pipe 30 and the oil sump of the first compressor 10, and the second bend section 32 is no higher than the second connection point between the oil balancing pipe 30 and the oil sump of the second compressor 20. The first and second connection points are located at the same horizontal position. The connection point between the pressure-inducing pipe 40 and the oil balancing pipe 30 is located between the first bend section 31 and the second bend section 32.

[0034] In this way, the first bending section 31 and the second bending section 32 can accommodate lubricating oil. When the medium in the suction main pipe 61 flows from the pressure-introducing pipe 40 toward the first compressor 10 and the second compressor 20, it can push the lubricating oil contained in the first bending section 31 and the second bending section 32 toward the two compressors, thereby better preventing the lubricating oil from being transferred.

[0035] Furthermore, in one embodiment, the first bending section 31 and the second bending section 32 are both V-shaped. In this way, the structures of the first bending section 31 and the second bending section 32 are simple, and can better prevent the transfer of lubricating oil.

[0036] Specifically, the V-shaped structure of the first bending section 31 and the second bending section 32 can be set as a symmetrical structure, and the symmetry axis is parallel to the direction of gravity. Of course, the first bending section 31 and the second bending section 32 can also be set as a V-shaped structure with one side parallel to the direction of gravity. The specific setting can be reasonable according to actual needs.

[0037] In one embodiment, if Figure 1As shown, the air intake main pipe 61 is provided with a gas-liquid separator 64, and the air intake main pipe 61 includes a first pipe section 611 and a second pipe section 612. The first pipe section 611 is connected to the inlet of the gas-liquid separator 64, and the second pipe section 612 is connected to the outlet of the gas-liquid separator 64. The second pipe section 612 is connected to the first air intake branch pipe 62 and the second air intake branch pipe 63.

[0038] The gas-liquid separator 64 can separate the liquid from the gaseous medium to ensure that the medium entering the first compressor 10 and the second compressor 20 is gaseous, thereby preventing liquid hammer and improving safety.

[0039] Furthermore, the connection between the pressure-inducing pipe 40 and the main suction pipe 61 can be located at an appropriate position on the main suction pipe 61 based on pressure requirements. For example, if a higher pressure is required at the connection between the pressure-inducing pipe 40 and the oil-balancing pipe 30, the connection between the pressure-inducing pipe 40 and the main suction pipe 61 can be located on the first pipe section 611. If a lower pressure requirement is required, the connection between the pressure-inducing pipe 40 and the main suction pipe 61 can be located on the second pipe section 612. The specific location can be appropriately determined based on actual requirements.

[0040] In this embodiment, if Figure 1 As shown, the connection between the pressure-inducing pipe 40 and the air suction main pipe 61 is specifically provided on the second pipe section 612 of the air suction main pipe 61 .

[0041] Since the resistance and flow rate difference within the suction line 60 affect the oil return volume of the first compressor 10 and the second compressor 20, the resistance and flow rate difference are mainly formed in the first suction branch pipe 62 and the second suction branch pipe 63. Therefore, to reduce the impact of the first suction branch pipe 62 and the second suction branch pipe 63 on the oil return volume, in one embodiment, the inner diameter of the first suction branch pipe 62 can be set to be equal to the inner diameter of the second suction branch pipe 63. Furthermore, the length of the first suction branch pipe 62 can be set to be equal to the length of the second suction branch pipe 63.

[0042] That is, by making the structure and length of the first and second suction branch pipes 62 and 63 substantially identical, the flow resistance of the media within them can be kept similar, thereby reducing the difference in flow rate entering the first and second compressors 10 and 20, and reducing the difference in return oil volume caused by structural factors. This further enhances the oil balancing effect of the parallel compressor oil balancing device 100.

[0043] In one embodiment, the parallel compressor oil balancing device 100 further includes an exhaust pipeline 70, which includes an exhaust main pipe 71 and a first exhaust branch pipe 72 and a second exhaust branch pipe 73 connected to the exhaust main pipe 71. The first exhaust branch pipe 72 and the second exhaust branch pipe 73 are arranged in parallel. The first exhaust branch pipe 72 is connected to the exhaust port of the first compressor 10, and the second exhaust branch pipe 73 is connected to the exhaust port of the second compressor 20. In this way, parallel exhaust of the first compressor 10 and the second compressor 20 can be achieved.

[0044] The present application also provides an air-conditioning system, which includes the parallel compressor oil balancing device 100 according to any one of the above embodiments.

[0045] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of patent protection for the present application shall be determined by the appended claims.

Claims

1. A parallel compressor oil balancing device, characterized in that: The invention comprises a first compressor (10), a second compressor (20), an air intake pipeline (60), an oil equalizing pipe (30), a pressure guide pipe (40) and a control valve (50); the air intake pipeline (60) comprises an air intake main pipe (61) and a first air intake branch pipe (62) and a second air intake branch pipe (63) connected to the air intake main pipe (61); the first air intake branch pipe (62) is connected to the air intake port of the first compressor (10), and the second air intake branch pipe (63) is connected to the air intake port of the second compressor (20); The two ends of the oil balancing pipe (30) are respectively connected to the oil pool of the first compressor (10) and the oil pool of the second compressor (20); one end of the pressure-inducing pipe (40) is connected to the oil balancing pipe (30), and the other end is connected to the suction main pipe (61); wherein the control valve (50) is provided on the pressure-inducing pipe (40) for controlling the on-off of the pressure-inducing pipe (40).

2. The parallel compressor oil balancing device according to claim 1, characterized in that: The oil balancing pipe (30) is provided with a first bending section (31) and a second bending section (32), wherein the first bending section (31) is arranged close to the first compressor (10), and the second bending section (32) is arranged close to the second compressor (20), and the first bending section (31) is not higher than a first connection point at which the oil balancing pipe (30) is connected to the oil pool of the first compressor (10), and the second bending section (32) is not higher than a second connection point at which the oil balancing pipe (30) is connected to the oil pool of the second compressor (20), and the first connection point and the second connection point are located at the same horizontal position; Wherein, the connection point between the pressure-inducing pipe (40) and the oil-balancing pipe (30) is provided between the first bending section (31) and the second bending section (32).

3. The parallel compressor oil balancing device according to claim 2, characterized in that: The first bending section (31) and the second bending section (32) are both V-shaped.

4. The parallel compressor oil balancing device according to any one of claims 1 to 3, characterized in that: The air intake main pipe (61) is provided with a gas-liquid separator (64), and the air intake main pipe (61) comprises a first pipe section (611) and a second pipe section (612), wherein the first pipe section (611) is communicated with the inlet of the gas-liquid separator (64), and the second pipe section (612) is communicated with the outlet of the gas-liquid separator (64); The second pipe section (612) is connected to the first air intake branch pipe (62) and the second air intake branch pipe (63).

5. The parallel compressor oil balancing device according to claim 4, characterized in that: The connection point between the pressure-inducing pipe (40) and the main air intake pipe (61) is located on the first pipe section (611).

6. The parallel compressor oil balancing device according to claim 4, characterized in that: The connection point between the pressure-inducing pipe (40) and the main air intake pipe (61) is located on the second pipe section (612).

7. The parallel compressor oil balancing device according to any one of claims 1-3 or 5-6, characterized in that: The length of the first air suction branch pipe (62) is equal to the length of the second air suction branch pipe (63); The inner diameter of the first air suction branch pipe (62) is equal to the inner diameter of the second air suction branch pipe (63).

8. The parallel compressor oil balancing device according to any one of claims 1-3 or 5-6, characterized in that: The control valve (50) is configured as a solenoid valve or an electric ball valve.

9. The parallel compressor oil balancing device according to any one of claims 1-3 or 5-6, characterized in that: The parallel compressor oil balancing device further comprises an exhaust pipeline (70), wherein the exhaust pipeline (70) comprises an exhaust main pipe (71) and a first exhaust branch pipe (72) and a second exhaust branch pipe (73) connected to the exhaust main pipe (71); the first exhaust branch pipe (72) and the second exhaust branch pipe (73) are arranged in parallel; the first exhaust branch pipe (72) is connected to the exhaust port of the first compressor (10), and the second exhaust branch pipe (73) is connected to the exhaust port of the second compressor (20).

10. An air conditioning system, characterized in that: It comprises the parallel compressor oil balancing device as described in any one of claims 1 to claim 9.

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