Rotary compressor upper flange, Rotary compressor, Air conditioner

Abstract

This invention provides an upper flange for a rotary compressor, a rotary compressor, and an air conditioner. The upper flange includes a flange body, which comprises a flange plate and an outer cylinder on the upper end face of the flange plate. The outer cylinder has a first central through hole extending through both ends of the flange plate along its axial direction. An inner cylinder is coaxially assembled within the first central through hole. The inner cylinder has a second central through hole extending through both ends of its axial direction. The second central through hole is used to cooperate with a crankshaft to form a rotary friction pair. A first oil return channel is formed between the inner circular wall surface of the outer cylinder and the outer circular wall surface of the inner cylinder. A spiral opening groove is formed on the hole wall surface of the second central through hole. A connecting hole is also constructed within the inner cylinder, connecting the spiral opening groove and the first oil return channel. In this invention, the first oil return channel is constructed on the exposed surfaces of the first central through hole and the inner cylinder, simplifying the groove processing technology, reducing processing difficulty, and improving processing efficiency.

Description

Technical Field

[0001] This invention belongs to the field of air conditioning technology, specifically relating to a top flange for a rotary compressor, a rotary compressor, and an air conditioner. Background Technology

[0002] Figure 1 The diagram shows the overall assembly structure of a conventional rotary compressor. A conventional rotary compressor mainly consists of a pump body assembly, motor assembly, distributor assembly, housing assembly, upper cover, and lower cover. The housing assembly, upper cover, and lower cover work together to form a sealed housing. The pump body assembly and motor assembly are assembled inside the housing. The pump body assembly includes major components such as an upper flange, cylinder, crankshaft, rollers, and lower flange. These components work together to form a sealed cavity. The motor assembly includes a stator assembly and a rotor assembly. The rotary compressor uses the electromagnetic force generated between the motor rotor assembly and stator assembly to drive the pump crankshaft. Under the driving force of the crankshaft rotation, the volume of the pump body cavity continuously changes, achieving periodic intake, compression, and exhaust. The oil-gas mixture discharged from the pump body cavity enters the lower chamber of the motor, then flows through the motor flow channel to the upper chamber of the motor, and finally exits the compressor into the air conditioning system (flow path as shown). Figure 1 (As shown by the dashed arrow in the image).

[0003] The oil passages within the pump body pump lubricating oil to the contact surfaces of moving parts, thereby achieving lubrication, cooling, and heat dissipation. The oil passage structure of the main and auxiliary bearings (i.e., the upper and lower flanges) of a conventional rolling rotary compressor is as follows: The crankshaft has a central oil hole, and the roots of the long and short crankshafts are respectively designed with side oil holes communicating with the central oil hole. An oil pumping device (e.g., ...) is installed in the inlet of the central oil hole. Figure 1 As shown in the diagram, the inner surfaces of the upper and lower flanges are respectively provided with spiral oil grooves. A certain amount of lubricating oil is contained in the lower part of the housing. When the compressor is running, under the action of the crankshaft center oil hole pumping device, the lubricating oil in the bottom oil sump is pumped into the center oil hole, and then pumped through the side oil holes at the roots of the crankshaft's long and short shafts to the ends of the inner surfaces of the lower and upper flanges, respectively. Then, it is pumped through the spiral oil grooves on the upper and lower flanges to the friction pairs (main and auxiliary bearings) between the upper and lower flanges and the crankshaft's long and short shafts, thereby achieving oil circuit lubrication of the main and auxiliary bearings (the main bearing lubricating oil flow path, such as...). Figure 1 (As indicated by the solid arrow).

[0004] When the compressor operates at high frequency, a large amount of lubricating oil is pumped out from the upper flange spiral oil groove to the lower chamber of the motor, and then carried by the high-speed airflow through the motor flow channel hole to the upper chamber of the motor, and then discharged into the system. This results in a high oil discharge rate when the compressor is running at high frequency, which reduces the performance of the compressor and increases the reliability risk of oil shortage inside the compressor.

[0005] Based on the aforementioned technical bottlenecks in conventional compressor oil circuit structures under high-frequency operating conditions, in related technologies, such as Figures 2 to 5 As shown, by opening an oil return channel connected to the oil sump at the bottom of the compressor on the inner circular surface of the upper flange or in the flange body, the lubricating oil circuit can circulate inside the pump body, avoiding the centrifugal force and gas force of the crankshaft rotation from carrying the lubricating oil into the upper and lower chambers of the motor, greatly reducing the oil content in the upper and lower chambers of the motor, thereby reducing the oil discharge rate of the compressor.

[0006] However, when the oil return channel is located on the inner surface of the upper flange, it will greatly reduce the effective bearing contact area between the upper flange and the crankshaft, weaken the bearing capacity of the main bearing (i.e., the upper flange), and the machining process and deburring process will be complicated. When the oil return channel is located inside the upper flange body, the machining process is complicated and the machining difficulty is greater.

[0007] Furthermore, in high-frequency rotating compressors, the bearing stress and structural strength deteriorate significantly. To optimize bearing contact stress, stress distribution, and structural strength, it is typically necessary to increase the flexible groove depth H while decreasing the flexible groove width W (e.g., ...). Figure 5 Only when the flexible groove is too deep or too narrow (i.e., H is too large and W is too small) can a better effect be achieved. However, if the flexible groove is too deep or too narrow (i.e., H is too large and W is too small), many processing problems such as difficulty in cutting, tool breakage, and difficulty in cleaning burrs will easily occur. Summary of the Invention

[0008] Therefore, the present invention provides an upper flange for a rotary compressor, a rotary compressor, and an air conditioner, which can overcome the technical problems of complex processing and high processing difficulty in the related art of setting an oil return channel in the upper flange body.

[0009] To address the aforementioned problems, this invention provides an upper flange for a rotary compressor, comprising a flange body, the flange body including a flange plate and an outer cylinder located on the upper end face of the flange plate, the outer cylinder having a first central through hole extending axially through both ends of the outer cylinder along the flange plate, an inner cylinder coaxially assembled within the first central through hole, the inner cylinder having a second central through hole extending axially through both ends of the inner cylinder, the second central through hole being used to cooperate with a crankshaft to form a rotary friction pair, a first oil return channel being formed between the inner circular wall surface of the outer cylinder and the outer circular wall surface of the inner cylinder, a spiral opening groove being formed on the hole wall surface of the second central through hole, and a connecting hole being constructed within the inner cylinder, the connecting hole connecting the spiral opening groove and the first oil return channel.

[0010] In some embodiments, the first return oil channel includes an opening groove constructed on one of the outer cylinder and the inner cylinder, and a wall surface constructed on the other of the outer cylinder and the inner cylinder that is sealed to the opening of the opening groove.

[0011] In some embodiments, the inner cylinder is made of cast iron, and the outer cylinder has a lower density than the cast iron.

[0012] In some embodiments, the outer cylinder is made of powder metallurgy.

[0013] In some embodiments, the outer cylinder and the inner cylinder are interference-fitted; and / or, the flange body is integrally cast; and / or, the inner cylinder is milled.

[0014] In some embodiments, the inner end of the outer cylinder and the inner cylinder near the pump body cavity of the compressor is the inner end, and a flexible groove is formed on the end face of the inner end, and the flexible groove is formed by both the inner cylinder and the outer cylinder.

[0015] In some embodiments, an inner annular groove is formed on the outer wall of the inner cylinder, and an outer annular groove is formed on the wall of the first central through hole. The longitudinal sections of both the inner and outer annular grooves are L-shaped, and the outer and inner annular grooves together form the flexible groove.

[0016] In some embodiments, a second oil return channel is also constructed within the flange body, the inlet of which is connected to the outlet of the first oil return channel to guide the lubricating oil returning in the first oil return channel back to the compressor oil sump.

[0017] The present invention also provides a rotary compressor, including a pump body assembly, the pump body assembly including the above-described rotary compressor upper flange.

[0018] The present invention also provides an air conditioner including the rotary compressor described above.

[0019] The rotary compressor, the rotary compressor, and the air conditioner provided by this invention have the following beneficial effects:

[0020] The inner and outer cylinders are coaxially assembled, forming a first oil return channel between their mating surfaces. The first oil return channel is connected to the spiral opening groove through a connecting hole. This design eliminates the need for the first oil return channel to be located on the wall of the second central through hole, effectively preventing a reduction in the effective bearing contact area between the upper flange and the crankshaft, which would weaken the bearing capacity of the upper flange and simplify the machining and deburring processes. Furthermore, the first oil return channel is constructed on the exposed surface of the first central through hole (hole wall) and / or the inner cylinder (outer cylindrical wall), simplifying the groove machining process, reducing machining difficulty, and improving machining efficiency.

[0021] The first return oil channel is formed by the sealing assembly of the opening groove and the wall surface relative to each other. Thus, only one corresponding wall surface of the outer cylinder or inner cylinder needs to be machined or the corresponding groove needs to be designed by mold, which simplifies the processing process.

[0022] The outer cylinder has a lower material density than the cast iron. For example, the outer cylinder can be made of lightweight materials such as powder metallurgy. This can further reduce the overall weight of the upper flange, save material costs, and further improve the lightweight nature of the pump assembly and compressor. This will further lower the center of gravity of the pump assembly and compressor, and further improve the vibration stability of the whole machine.

[0023] The flexible groove is formed by the combination of corresponding structures on the two opposing circular walls of the inner and outer cylinders. In the specific processing, the inner cylinder and / or the outer cylinder can be processed separately on their exposed walls and then assembled to form the aforementioned flexible groove. This allows the processing of the flexible groove to be unrestricted by its size, solving many processing bottlenecks such as difficulty in cutting, tool breakage, and difficulty in burr removal in the processing of flexible groove structures with small width and large depth in conventional rotary compressors. Attached Figure Description

[0024] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the overall assembly structure of a conventional rotary compressor in related technologies;

[0026] Figure 2 This is a schematic diagram of the internal structure of a pump body assembly in related technologies. The arrows in the diagram indicate the flow direction of the lubricating oil.

[0027] Figure 3 This is a schematic diagram of the internal structure of another pump body component in related technologies. The arrows in the diagram indicate the flow direction of the lubricating oil.

[0028] Figure 4 This is a schematic diagram of the internal structure of another pump body component in related technologies. The arrows in the diagram indicate the flow direction of the lubricating oil.

[0029] Figure 5 yes Figure 4 A magnified view of section I in the middle, with arrows indicating the flow direction of the lubricating oil;

[0030] Figure 6This is a cross-sectional view of the upper flange of a rotary compressor according to an embodiment of the present invention, wherein the arrows in the figure indicate the flow direction of the lubricating oil;

[0031] Figure 7 yes Figure 6 A cross-sectional view of the flange body, with arrows indicating the flow direction of lubricating oil;

[0032] Figure 8 yes Figure 6 A cross-sectional view of the inner cylinder, with arrows indicating the flow direction of the lubricating oil;

[0033] Figure 9 It was applied Figure 6 A schematic diagram of the internal structure of the pump body assembly with the upper flange in the diagram, where the arrows indicate the flow direction of the lubricating oil;

[0034] Figure 10 This is a cross-sectional view of the upper flange of a rotary compressor according to another embodiment of the present invention, wherein the arrows in the figure indicate the flow direction of the lubricating oil;

[0035] Figure 11 It was applied Figure 10 A schematic diagram of the internal structure of the pump body assembly with the upper flange in the diagram, where the arrows indicate the flow direction of the lubricating oil;

[0036] Figure 12 This is a cross-sectional view of the upper flange of a rotary compressor according to another embodiment of the present invention, wherein the arrows in the figure indicate the flow direction of the lubricating oil;

[0037] Figure 13 It was applied Figure 12 A schematic diagram of the internal structure of the pump body assembly with the upper flange in the diagram, where the arrows indicate the flow direction of the lubricating oil;

[0038] Figure 14 This is a cross-sectional view of the upper flange of a rotary compressor according to another embodiment of the present invention. The arrows in the figure indicate the flow direction of the lubricating oil.

[0039] Figure 15 yes Figure 14 A cross-sectional view of the flange body, with arrows indicating the flow direction of lubricating oil;

[0040] Figure 16 yes Figure 14 The diagram shows a cross-sectional view of the inner cylinder, with arrows indicating the flow direction of the lubricating oil.

[0041] The attached figures are labeled as follows:

[0042] 1. Flange body; 11. Flange plate; 111. Oil drain groove; 12. Outer cylinder; 121. First central through hole; 122. Outer annular groove; 2. Inner cylinder; 21. Second central through hole; 22. Spiral opening groove; 23. Connecting hole; 24. Inner annular groove; 31. First return oil channel; 32. Second return oil channel; 4. Flexible groove; 100. Crankshaft; 1001. Central oil hole; 1002. Side oil hole; 1003. Eccentric part; 101. Cylinder; 102. Roller; 103. Lower flange. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0044] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0045] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90° or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0046] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0047] See Figure 6 and Figure 16 As shown, according to an embodiment of the present invention, a top flange for a rotary compressor is provided, comprising a flange body 1, the flange body 1 including a flange 11 and an outer cylinder 12 located on the upper end face of the flange 11. It is understood that when the upper flange is assembled into the pump body assembly, the lower end face of the aforementioned flange 11 is sealed to the upper end face of the cylinder 101. The outer cylinder 12 has a first central through hole 121 extending axially through both ends of the outer cylinder 12 along the flange 11. An inner cylinder 2 is coaxially assembled within the first central through hole 121. The inner cylinder 2 has a second central through hole 21 extending axially through both ends of the inner cylinder 2. The second central through hole 21 is used to cooperate with the crankshaft 100 to form a rotary friction pair (which is also the main bearing). A first oil return channel 31 is formed between the inner circular wall surface of the outer cylinder 12 and the outer circular wall surface of the inner cylinder 2. A spiral opening groove 22 is formed on the hole wall surface of the second central through hole 21. When lubricating oil enters the spiral opening groove 22, it will lubricate and cool the second central through hole 21 and the crankshaft 100. A connecting hole 23 is also constructed in the inner cylinder 2. The connecting hole 23 connects the spiral opening groove 22 and the first oil return channel 31. That is, the connecting hole 23 penetrates the inner circular wall surface and the outer circular wall surface of the inner cylinder 2.

[0048] In this technical solution, the inner cylinder 2 and the outer cylinder 12 are coaxially assembled, thereby forming a first oil return channel 31 between their mating surfaces. The first oil return channel 31 and the spiral opening groove 22 are connected by a connecting hole 23. This means that the first oil return channel 31 does not need to be opened on the wall surface of the second central through hole 21, effectively preventing the reduction of the effective bearing contact area between the upper flange and the crankshaft, which would weaken the bearing capacity of the upper flange, simplify the processing technology and deburring process. On the other hand, the aforementioned first oil return channel 31 is constructed on the exposed surface of the first central through hole 121 (hole wall surface) and / or the inner cylinder 2 (outer circular wall surface), which simplifies the groove processing technology, reduces the processing difficulty, and improves processing efficiency.

[0049] The aforementioned first oil return channel 31 can be formed by assembling two opposing grooves formed on the wall surface of the aforementioned first central through hole 121 and the outer circular wall surface of the inner cylinder 2. However, this method requires simultaneous machining of the aforementioned inner cylinder 2 and outer cylinder 12 or groove mold design, which makes the processing technology relatively complex. Therefore, in a preferred embodiment, the first oil return channel 31 includes an opening groove (not indicated in the figure) constructed on one of the outer cylinder 12 and inner cylinder 2, and a wall surface constructed on the other of the outer cylinder 12 and inner cylinder 2 that is sealed and connected to the opening of the opening groove.

[0050] In this technical solution, the first return oil channel 31 is formed by the assembly and sealing of the opening groove and the wall surface relative to each other. Thus, only the corresponding groove needs to be machined or designed by mold on the corresponding wall surface of either the outer cylinder 12 or the inner cylinder 2, simplifying the processing. In another preferred embodiment, the aforementioned opening groove is provided on the outer cylinder 12, so that the wall thickness (radial thickness) of the inner cylinder 2 can be designed to be smaller while maintaining the same structural strength. In this case, when the material of the inner cylinder 2 is cast iron, the mass of the inner cylinder 2 can be smaller, thereby reducing the overall mass of the upper flange. This is beneficial for the lightweight design of the upper flange, which in turn helps to reduce the center of gravity height of the pump assembly and the compressor on which it is used, thus optimizing the vibration stability of the compressor.

[0051] As mentioned above, the inner cylinder 2 can be made of cast iron to ensure the wear resistance between the inner cylinder 2 and the crankshaft 100, that is, to reduce the wear on the inner cylinder 2 during the rotation of the crankshaft 100. Due to the assembly relationship between the outer cylinder 12 and the inner cylinder 2 in the flange of this application, the material of the outer cylinder 12 can be rotated independently without being limited by the wear factor of the crankshaft 100. In a preferred embodiment, the material density of the outer cylinder 12 is less than that of the cast iron. For example, the material of the outer cylinder 12 is a lightweight material such as powder metallurgy. This can further reduce the overall weight of the upper flange, save material costs, and further improve the lightweight nature of the pump body assembly and compressor. This further lowers the center of gravity of the pump body assembly and compressor, and further improves the vibration stability of the whole machine.

[0052] It is understandable that the flange body 1 has a number of shapes and structures such as exhaust port, intake port, and connection hole. In order to simplify the processing of the flange body 1, in a specific embodiment, the flange body 1 is integrally cast. The inner cylinder 2 needs to be assembled with the crankshaft 100, and the processing accuracy requirements of the corresponding structure, such as the second central through hole 21, are high. Based on this, the inner cylinder 2 is formed by milling.

[0053] In one specific embodiment, the outer cylinder 12 and the inner cylinder 2 are interference-fitted. This assembly method is relatively simple in structure and assembly, easy to implement, and highly applicable.

[0054] See also Figures 14 to 16 As shown, in some embodiments, the outer cylinder 12 and the inner cylinder 2 are positioned at the inner end near the pump body cavity of the compressor (i.e., the inner end). Figure 14 (At the lower end of the indicated position), a flexible groove 4 is formed on the inner end face, and the flexible groove 4 is formed by both the inner cylinder 2 and the outer cylinder 12.

[0055] In this technical solution, the flexible groove 4 is formed by the combination of corresponding structures on the two opposing circular walls of the inner cylinder 2 and the outer cylinder 12. In specific processing, the inner cylinder 2 and / or the outer cylinder 12 can be processed separately on their exposed walls and then assembled to form the aforementioned flexible groove. This allows the processing of the flexible groove to be unrestricted by its size, solving many processing bottlenecks such as difficulty in cutting, tool breakage, and difficulty in cleaning burrs in the processing of flexible groove structures with small width and large depth in conventional rotary compressors.

[0056] In some embodiments, an inner annular groove 24 is formed on the outer wall of the inner cylinder 2, and an outer annular groove 122 is formed on the wall of the first central through hole 121. The longitudinal sections of the inner annular groove 24 and the outer annular groove 122 are both L-shaped, and the outer annular groove 122 and the inner annular groove 24 together form the flexible groove 4.

[0057] In this technical solution, the inner annular groove 24 on the inner cylinder 2 and the outer annular groove 122 on the outer cylinder 12 are combined to form a flexible groove 4, which allows the overall wall thickness (radial thickness) of the inner cylinder 2 to be designed to be relatively small, which is beneficial to the lightweight design of the upper flange.

[0058] In some embodiments, a second oil return channel 32 is also constructed within the flange body 1. The inlet (not labeled in the figure) of the second oil return channel 32 is connected to the outlet (not labeled in the figure) of the first oil return channel 31 to guide the lubricating oil flowing back in the first oil return channel 31 back to the compressor oil sump. The lower end face of the flange 11 has a mating surface that mates with the cylinder 101 of the compressor. An oil drip groove 111 is constructed on the lower end face. The outlet of the second oil return channel 32 is located within the oil drip groove 111, and the oil drip groove 111 protrudes radially outward from the mating surface along the flange 11. This allows the lubricating oil guided back by the first oil return channel 31 and the second oil return channel 32 to flow back to the lower oil sump through the aforementioned oil drip groove 111, reducing the compressor's oil discharge rate and ensuring sufficient lubricating oil in the compressor.

[0059] According to an embodiment of the present invention, a rotary compressor is also provided, including a pump body assembly, the pump body assembly including the above-mentioned rotary compressor flange, the aforementioned rotary compressor being any of the rolling rotor compressor, rotary cylinder compressor, sliding vane compressor, and scroll compressor described above, and can be a single-cylinder, double-cylinder, or multi-cylinder compressor, and the present invention does not particularly limit it.

[0060] by Figure 9 Taking the rolling rotor compressor shown as an example, the aforementioned pump body assembly also includes main components such as cylinder 101, crankshaft 100, roller 102 and lower flange 103. The crankshaft 100 is provided with a central oil hole 1001, and the lower root of the crankshaft 100 that mates with the upper flange is provided with a side oil hole 1002.

[0061] According to an embodiment of the present invention, an air conditioner is also provided, including the rotary compressor described above.

[0062] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A flange for a rotary compressor, characterized in that, The system includes a flange body (1), which includes a flange (11) and an outer cylinder (12) located on the upper end face of the flange (11). The outer cylinder (12) has a first central through hole (121) that extends axially through both ends of the outer cylinder (12) along the flange (11). An inner cylinder (2) is coaxially assembled in the first central through hole (121). The inner cylinder (2) has a second central through hole (21) that extends axially through both ends of the inner cylinder (2). The second central through hole (21) is used to cooperate with a crankshaft (100) to form a rotary friction pair. A first oil return channel (31) is formed between the inner circular wall surface of the outer cylinder (12) and the outer circular wall surface of the inner cylinder (2). A spiral opening groove (22) is formed on the hole wall surface of the second central through hole (21). The inner cylinder (2) is also constructed with a connecting hole (23), which connects the spiral opening groove (22) and the first return oil channel (31). The inner cylinder (2) is made of cast iron, and the material density of the outer cylinder (12) is less than that of the cast iron. The inner end of the outer cylinder (12) and the inner cylinder (2) near the pump body cavity of the compressor is the inner end. A flexible groove (4) is formed on the inner end face. An inner annular groove (24) is formed on the outer cylinder wall of the inner cylinder (2), and an outer annular groove (122) is formed on the hole wall of the first central through hole (121). The longitudinal section of the inner annular groove (24) and the outer annular groove (122) are both L-shaped. The outer annular groove (122) and the inner annular groove (24) together form the flexible groove (4).

2. The upper flange for a rotary compressor according to claim 1, characterized in that, The first return oil channel (31) includes an opening groove constructed on one of the outer cylinder (12) and the inner cylinder (2) and a wall surface constructed on the other of the outer cylinder (12) and the inner cylinder (2) that is sealed to the opening of the opening groove.

3. The upper flange for a rotary compressor according to claim 1, characterized in that, The outer cylinder (12) is made of powder metallurgy.

4. The upper flange for a rotary compressor according to claim 1, characterized in that, The outer cylinder (12) and the inner cylinder (2) are interference-fitted; and / or the flange body (1) is integrally cast; and / or the inner cylinder (2) is formed by milling.

5. The upper flange for a rotary compressor according to claim 1, characterized in that, The flange body (1) is also provided with a second oil return channel (32), the inlet of which is connected to the outlet of the first oil return channel (31) to guide the lubricating oil returning in the first oil return channel (31) back to the compressor oil sump.

6. A rotary compressor, comprising a pump body assembly, characterized in that, The pump assembly includes the upper flange for a rotary compressor as described in any one of claims 1 to 5.

7. An air conditioner, characterized in that, Includes the rotary compressor as described in claim 6.

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