Oil absorption structure, pump body assembly and compressor

Abstract

This invention provides an oil suction structure, a pump assembly, and a compressor. The oil suction structure includes an oil inlet section (1) and an oil outlet section (2), the oil outlet section (2) being cylindrical. The oil inlet section (1) and the oil outlet section (2) are fixedly connected. An oil passage (3) is provided inside both the oil inlet section (1) and the oil outlet section (2) along the axial direction of the oil outlet section (2), penetrating both sections. The cross-sectional area of ​​the oil passage (3) in the oil inlet section (1) is smaller than the cross-sectional area of ​​the oil passage (3) in the oil outlet section (2). According to the oil suction structure of this invention, the pumping volume and pumping height of the pump assembly can be increased, the problem of pump bearing wear can be solved, and the operational reliability of the compressor can be improved.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and more specifically, to an oil suction structure, a pump assembly, and a compressor. Background Technology

[0002] With the development of rotary compressor technology, the demand for low-cost and miniaturized compressor development is becoming increasingly strong. While compressors are being miniaturized, pump displacement is also increasing. During the miniaturization process, when the compressor size is reduced and the displacement is increased, the oil circuit structure can no longer meet the pump lubrication requirements when the system has low superheat or the compressor has low oil level. Pump bearing wear is likely to occur at high frequency and low oil level, leading to compressor reliability issues. Summary of the Invention

[0003] The main objective of this invention is to provide an oil suction structure, a pump body assembly, and a compressor, which can increase the pumping volume and oil level of the pump body assembly, solve the problem of pump body bearing wear, and improve the operational reliability of the compressor.

[0004] To achieve the above objectives, according to one aspect of the present invention, an oil suction structure is provided, including an oil inlet section and an oil outlet section. The oil outlet section is cylindrical, and the oil inlet section and the oil outlet section are fixedly connected. An oil passage is provided inside the oil inlet section and the oil outlet section, extending through the oil inlet section and the oil outlet section along the axial direction of the oil outlet section. The cross-sectional area of ​​the oil passage in the oil inlet section is smaller than the cross-sectional area of ​​the oil passage in the oil outlet section.

[0005] Furthermore, the oil inlet section has a flat structure.

[0006] Furthermore, the flat structure includes two opposing arc surfaces and two opposing planes, with the arc surfaces flush with the cylindrical surface of the oil outlet section and the two planes located between the two arc surfaces.

[0007] Furthermore, the diameter of the oil outlet section is D, the thickness of the flat structure is H, H / D=λ, 0.4≤λ≤0.6.

[0008] Furthermore, λ = 0.49.

[0009] Furthermore, the length of the oil inlet section along the axial direction of the oil outlet section accounts for more than 2 / 3 of the sum of the axial lengths of the oil inlet section and the oil outlet section.

[0010] Furthermore, both the oil inlet section and the oil outlet section have equal wall thickness structures.

[0011] Furthermore, an oil suction hole is provided at the oil inlet end of the oil inlet section, and the oil suction hole is connected to the oil passage.

[0012] Furthermore, the oil suction hole is either a round hole or an oblong hole.

[0013] Furthermore, there are multiple oil suction holes, which are symmetrically distributed about the central axis of the oil outlet section.

[0014] According to another aspect of the present invention, a pump body assembly is provided, including a compression assembly and a crankshaft, the compression assembly being mounted on the crankshaft, and further including the aforementioned oil suction structure, the crankshaft including a short shaft section, and an oil outlet section being sleeved within the short shaft section.

[0015] According to another aspect of the present invention, a compressor is provided, comprising the oil suction structure described above or the pump body assembly described above.

[0016] According to the technical solution of this invention, the oil suction structure includes an oil inlet section and an oil outlet section. The oil outlet section is cylindrical, and the oil inlet section and the oil outlet section are fixedly connected. An oil passage is provided inside both the oil inlet section and the oil outlet section, extending axially through both sections. The cross-sectional area of ​​the oil passage in the oil inlet section is smaller than that in the oil outlet section. This oil suction structure, divided into an oil inlet section and an oil outlet section, with the smaller cross-sectional area of ​​the oil passage in the oil inlet section compared to the oil outlet section, reduces the oil flow area, increases the centrifugal force of the lubricating oil at the suction port, and increases the lubricating oil flow velocity. This, in turn, increases the pumping height and pumping volume of the pump body assembly, ensuring sufficient lubricating oil reaches the pump body bearings for lubrication, thus solving the problem of pump body bearing wear and improving the reliability of compressor operation. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 A three-dimensional structural schematic diagram of the oil-absorbing structure according to an embodiment of the present invention is shown;

[0019] Figure 2 A schematic diagram of the oil-absorbing structure according to an embodiment of the present invention is shown;

[0020] Figure 3 It shows Figure 2 A schematic diagram of the AA-direction cross-section structure;

[0021] Figure 4 A schematic diagram of the oil-absorbing structure according to an embodiment of the present invention is shown;

[0022] Figure 5 It shows Figure 4 Schematic diagram of the BB-direction cross-section structure;

[0023] Figure 6 A three-dimensional structural schematic diagram of an oil-absorbing structure according to an embodiment of the present invention is shown;

[0024] Figure 7 A three-dimensional structural schematic diagram of an oil-absorbing structure according to an embodiment of the present invention is shown;

[0025] Figure 8 A cross-sectional structural diagram of the pump body assembly according to an embodiment of the present invention is shown; and

[0026] Figure 9 A graph showing the relationship between the pump oil volume and λ of the pump body assembly according to an embodiment of the present invention is shown.

[0027] The above figures include the following reference numerals:

[0028] 1. Oil inlet section; 2. Oil outlet section; 3. Oil passage; 4. Arc surface; 5. Plane surface; 6. Oil suction hole; 7. Compression assembly; 8. Crankshaft; 9. Short shaft section; 10. Oil guide plate. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] The inventors discovered through research that the pump body wear problem that occurs after the compressor is miniaturized and has a large displacement is mainly caused by insufficient oil supply at low oil levels. Insufficient oil supply includes insufficient oil supply height and insufficient oil supply volume.

[0031] Analysis of the insufficient oil supply problem revealed that the cause was a high solubility of the refrigerant in the compressor when the system's suction and discharge superheat was low. This resulted in a low compressor oil level, leading to insufficient oil flow and insufficient oil level. Compressors often experience low superheat during system matching. Low suction and discharge superheat causes a rapid increase in the solubility of the refrigerant and lubricating oil, resulting in a rapid increase in the compressor's oil discharge rate and a rapid decrease in the oil level in the compressor oil sump. This rapid decrease in both oil flow and oil level ultimately leads to insufficient oil and wear on the compressor's pump body bearings.

[0032] To effectively solve this problem, it is necessary to increase the oil pumping volume and oil level of the compressor to meet the lubrication requirements of the pump body bearings.

[0033] Based on the above analysis, see Figures 1 to 8 As shown in the embodiment of the present invention, the oil suction structure includes an oil inlet section 1 and an oil outlet section 2. The oil outlet section 2 is cylindrical. The oil inlet section 1 and the oil outlet section 2 are fixedly connected. An oil passage 3 is provided inside the oil inlet section 1 and the oil outlet section 2, which runs through the oil inlet section 1 and the oil outlet section 2 along the axial direction of the oil outlet section 2. The cross-sectional area of ​​the oil passage 3 in the oil inlet section 1 is smaller than the cross-sectional area of ​​the oil passage 3 in the oil outlet section 2.

[0034] The oil suction structure is divided into an oil inlet section 1 and an oil outlet section 2. The cross-sectional area of ​​the oil passage 3 in the oil inlet section 1 is smaller than that in the oil outlet section 2. By utilizing the smaller cross-sectional area of ​​the oil passage 3 in the oil inlet section 1, the oil flow area can be reduced, the centrifugal force of the lubricating oil at the oil suction port can be increased, the flow rate of the lubricating oil can be increased, and the pumping height and pumping volume of the pump body assembly can be increased. This allows the lubricating oil to reach the pump body bearing in sufficient quantities, lubricate the pump body bearing, solve the problem of pump body bearing wear, and improve the reliability of compressor operation.

[0035] Experimental studies on compressor oil pumping under no-load conditions revealed that, with the oil suction structure of this invention, the oil passage 3 at the oil inlet end, with its relatively small cross-sectional area, has a longer length and a smaller flow area, thus increasing the oil flow velocity. Compared to the known oil suction structures of the inventors, the centrifugal force effect at the oil inlet end is more pronounced in the oil suction structure of this embodiment. Comparative experimental tests showed that, compared to the known oil suction structures of the inventors, the oil pumping volume and height of the compressor pump assembly are significantly improved with the oil suction structure of this invention. In particular, the oil pumping volume is effectively increased at high frequencies and low oil levels, solving the problem of insufficient oil pumping at low oil levels due to low superheat in air conditioning systems, improving compressor reliability, and addressing the wear problem of the compressor during system application.

[0036] Experimental tests revealed that, compared to the known oil suction structures of the inventors, the oil suction structure of this invention can increase the oil pumping volume by more than 30% and the oil pumping height by more than 20%, ensuring the reliability of the compressor pump body and ensuring stable operation of the compressor. At the same time, due to the increase in oil pumping height and volume, the lubricating oil in the gap between the compressor roller end face and the upper and lower flange end faces increases, ensuring end face sealing and improving the compressor's energy efficiency at low oil levels.

[0037] In one embodiment, the oil inlet section 1 has a flat structure, which allows the oil inlet section 1 to have different dimensions in the radial direction. This allows the oil inlet section 1 to have the same dimensions as the oil outlet section 2 in one direction, so that the sidewall of the oil inlet section 1 can form a good positioning for the installation of the oil inlet section 1 and improve the stability of the installation structure of the oil inlet section 1. On the other hand, it can reduce the size of the oil inlet section 1, so that the overall cross-sectional area of ​​the oil inlet section 1 is reduced, thereby reducing the cross-sectional area of ​​the oil passage 3 located in the oil inlet section 1. This satisfies the purpose of increasing the centrifugal force of the lubricating oil at the oil suction port and increasing the flow rate of the lubricating oil.

[0038] In one embodiment, the flat structure includes two opposing arc surfaces 4 and two opposing planes 5, the arc surfaces 4 being flush with the cylindrical surface of the oil outlet section 2, and the two planes 5 being located between the two arc surfaces 4.

[0039] In this embodiment, the flat structure is a symmetrical structure, and the diameters of the two arc surfaces 4 are the same as the diameter of the oil outlet section 2, so that the arc surfaces 4 and the outer surface of the oil outlet section 2 are an integral structure. This allows the arc surfaces 4 and the oil outlet section 2 of the flat structure to form a good positioning effect for the installation of the oil suction structure. The setting of the two planes 5 can reduce the processing difficulty of the flat structure, reduce the processing cost, and make it easier to implement.

[0040] In one embodiment, the oil inlet section 1 and the oil outlet section 2 are integrally formed structures.

[0041] Since the cross-section changes between the oil inlet section 1 and the oil outlet section 2, a transition connecting section is provided between them to reduce the adverse effects of this cross-section change on the structure. The cross-sectional area of ​​the transition connecting section increases along the direction from the oil inlet section 1 to the oil outlet section 2. The shape of the small end of the transition connecting section is the same as the cross-sectional shape of the oil inlet section 1, and the shape of the large end of the transition connecting section is the same as the cross-sectional shape of the oil outlet section 2. This allows the cross-sectional change of the oil suction structure to be realized while ensuring the overall structural strength, so that the oil suction structure can have good structural performance.

[0042] In one embodiment, the diameter of the oil outlet section 2 is D, the thickness of the flat structure is H, H / D=λ, and 0.4≤λ≤0.6.

[0043] In one embodiment, λ = 0.49.

[0044] See also Figure 9 As shown, simulation calculations of the oil pumping volume at the crankshaft inlet reveal that when the ratio between the thickness H of the flat structure and the diameter D of the oil outlet section 2 is too small, it indicates that the thickness of the flat structure is too small and the flatness is too high. This can easily cause excessive agitation of the oil sump during high-speed rotation, leading to an unstable oil level in the oil sump. Consequently, the lubricating oil at the crankshaft inlet may contain refrigerant gas, and the oil pumping volume will decrease. Conversely, when the ratio between the thickness H of the flat structure and the diameter D of the oil outlet section 2 is too large, it indicates that the thickness of the flat structure is too large and the flatness is too small. This can result in insufficient centrifugal force during rotation, making it impossible to effectively increase the oil pumping volume and pumping height.

[0045] When within the range described above in this embodiment, it can be ensured that the flat structure can effectively agitate the oil sump and provide sufficient centrifugal force, while avoiding excessive agitation. This can effectively increase the pump oil volume and pump oil height while maintaining a stable oil level in the oil sump, thus meeting the lubrication requirements of the pump body bearings.

[0046] In one embodiment, the length of the oil inlet section 1 along the axial direction of the oil outlet section 2 is more than 2 / 3 of the sum of the lengths of the oil inlet section 1 and the oil outlet section 2 in the axial direction, thereby ensuring that the oil inlet section 1 can provide a sufficient length of centrifugal force to ensure the pumping volume and pumping height of the lubricating oil.

[0047] In one embodiment, both the oil inlet section 1 and the oil outlet section 2 are structures with equal wall thickness.

[0048] In one embodiment, an oil suction hole 6 is provided at the oil inlet end of the oil inlet section 1, and the oil suction hole 6 is connected to the oil passage 3. Lubricating oil can enter the oil passage 3 through the oil suction hole 6, and then be transported to the position to be lubricated under the action of centrifugal force generated when the oil suction structure rotates.

[0049] In one embodiment, the oil suction hole 6 is a round hole or an oblong hole. The area of ​​the oil suction hole 6 is smaller than the area of ​​the oil passage 3, which can ensure the pumping effect of the lubricating oil.

[0050] In this embodiment, the oil suction hole 6 is a round hole or an oblong hole. The oil suction hole 6 is located at the center of the end of the oil inlet section 1, and the oil suction hole 6 adopts a centrally symmetrical structure, that is, the oil suction hole 6 is centrally symmetrical about the central axis of the oil outlet section 2. This allows the lubricating oil entering from the oil suction hole 6 to be more even when the oil suction structure rotates, thereby improving the flow efficiency of the lubricating oil.

[0051] In one embodiment, there are multiple oil suction holes 6, which are symmetrically distributed about the central axis of the oil outlet section 2. In this embodiment, the aforementioned single-hole structure is replaced with a symmetrically arranged multiple small-hole structure, and the total oil suction hole area of ​​the small-hole structure remains the same as in the previous embodiment. The shape of the oil suction holes 6 is, for example, a circular hole. When the crankshaft and oil suction structure rotate at high speed, the small-hole structure can stabilize the oil surface, reduce oil surface fluctuations, and reduce agitation during the oil suction process.

[0052] See also Figures 1 to 8 As shown, according to an embodiment of the present invention, the pump body assembly includes a compression assembly 7 and a crankshaft 8. The compression assembly 7 is mounted on the crankshaft 8 and also includes the aforementioned oil suction structure. The crankshaft 8 includes a short shaft section 9, and the oil outlet section 2 is sleeved within the short shaft section 9.

[0053] In this embodiment, the pump body assembly includes a compression component 7 for compressing fluid and a crankshaft 8 connected to the compression component 7. The short shaft section 9 of the crankshaft 8 is installed in the shaft hole of the lower flange. The short shaft side of the lower flange where the crankshaft 8 connects to the compression component 7 is the oil inlet end. The oil suction structure is disposed on the pump body assembly and installed in the inner hole of the short shaft section 9 of the crankshaft 8. The oil guide plate 10 is installed in the oil suction structure and the inner hole of the short shaft section 9. One end of the oil suction structure connected to the short shaft section 9 of the crankshaft 8 is a round hole structure, which is installed with an interference fit with the inner hole of the short shaft section 9. The other end of the oil suction structure is a flat structure. The cross-sectional area of ​​the oil passage 3 in the flat structure is smaller than the cross-sectional area of ​​the oil passage 3 in the cylindrical structure of the oil outlet section 2.

[0054] The oil inlet section 1 of the oil suction structure has an oil suction hole 6 at its oil inlet end. The oil suction hole 6 can be a round hole, an oblong hole, or multiple small holes arranged symmetrically. When the oil suction structure rotates together with the crankshaft 8, the air conditioning system often experiences a low superheat in the intake and exhaust. When the superheat in the intake and exhaust is low, the solubility of the refrigerant and lubricating oil inside the compressor increases rapidly. As the compressor exhaust oil circulation rate increases, the oil level in the oil sump inside the compressor becomes low. Because the cross-sectional area of ​​the oil passage 3 in the flat structure at the inlet end of the oil suction structure is smaller than that in the cylindrical structure of the oil outlet section 2, the oil suction structure draws lubricating oil from the inlet end of the oil suction structure as the crankshaft 8 rotates. Under the centrifugal force of the guide plate 10 and the wall of the oil inlet section 1 of the oil suction structure, the oil quickly rises and is pumped to each friction pair through the outlet holes on the crankshaft 8 for lubrication and heat dissipation. Due to the centrifugal force of the flat structure, the pumping volume and pumping height of the compressor pump body assembly are increased, which solves the problem of oil shortage when the system is matched with low oil level, ensures the reliability of the compressor pump body assembly, and ensures stable operation of the compressor. At the same time, due to the increase in pumping height and pumping volume, the lubricating oil in the gap between the compressor roller end face and the upper and lower flange end faces increases, ensuring end face sealing and improving the compressor efficiency when the oil level is low.

[0055] According to an embodiment of the present invention, the compressor includes the oil suction structure described above or the pump body assembly described above.

[0056] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An oil absorption structure, characterized by, It includes an oil inlet section (1) and an oil outlet section (2), the oil outlet section (2) being cylindrical. The oil inlet section (1) and the oil outlet section (2) are fixedly connected. The oil inlet section (1) and the oil outlet section (2) are provided with an oil passage (3) that runs through the oil inlet section (1) and the oil outlet section (2) along the axial direction of the oil outlet section (2). The cross-sectional area of ​​the oil passage (3) of the oil inlet section (1) is smaller than the cross-sectional area of ​​the oil passage (3) of the oil outlet section (2). The oil inlet section (1) is a flat structure, and the flat structure includes two arcs arranged opposite to each other. The two arc surfaces (4) and two opposing planes (5) have the same diameter as the oil outlet section (2). The two planes (5) are located between the two arc surfaces (4) and form edges at the junction with the arc surfaces. The diameter of the oil outlet section (2) is D, the thickness of the flat structure is H, H / D=λ, 0.4≤λ≤0.6, and the length of the oil inlet section (1) along the axial direction of the oil outlet section (2) is more than 2 / 3 of the sum of the lengths of the oil inlet section (1) and the oil outlet section (2).

2. The oil absorption structure according to claim 1, wherein λ=0.

49.

3. The oil absorption structure according to any one of claims 1 to 2, wherein Both the oil inlet section (1) and the oil outlet section (2) are of equal wall thickness.

4. The oil-absorbing structure according to any one of claims 1 to 2, characterized in that, The oil inlet section (1) has an oil suction hole (6) at the oil inlet end, and the oil suction hole (6) is connected to the oil passage (3).

5. The oil-absorbing structure according to claim 4, characterized in that, The oil suction hole (6) is a round hole or an oblong hole.

6. The oil-absorbing structure according to claim 4, characterized in that, The number of oil suction holes (6) is multiple, and the multiple oil suction holes (6) are centrally symmetrically distributed about the central axis of the oil outlet section (2).

7. A pump body assembly comprising a compression assembly (7) and a crankshaft (8), said compression assembly (7) being mounted on said crankshaft (8), characterized in that, It also includes an oil-absorbing structure as described in any one of claims 1 to 6, wherein the crankshaft (8) includes a short shaft section (9), and the oil outlet section (2) is fitted inside the short shaft section (9).

8. A compressor, characterized in that, It includes the oil suction structure according to any one of claims 1 to 6 or the pump assembly according to claim 7.

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