Filter element replacement structure and vacuum pump

Abstract

The utility model belongs to the technical field of vacuum pumps, and particularly relates to a filter element replacement structure and a vacuum pump. In order to overcome the defect that an existing oil seal type rotary vane vacuum pump filter element is inconvenient to replace, the technical scheme adopted by the utility model is that the filter element replacement structure comprises a filter shell provided with a filter element installation cavity, a first thread part is formed at the outer end of the filter element installation cavity, and an air inlet hole is formed in the inner end of the filter element installation cavity; the oil mist filter element is provided with a second thread part matched with the first thread part of the filter shell and a control part exposed out of the filter shell; the control part is rotated to connect or separate the oil mist filter element and the filter shell, when the oil mist filter element is mounted on the filter shell, the inner end of the oil mist filter element is sealed with the inner end of the filter element mounting cavity, and the outer end of the oil mist filter element is sealed with the outer end of the filter element mounting cavity. The utility model has the beneficial effect that the filter element is very convenient to disassemble and assemble.

Description

Technical Field

[0001] The utility model belongs to the technical field of vacuum pumps, and in particular relates to a filter element replacement structure and a vacuum pump. Background Art

[0002] Oil-sealed rotary vane vacuum pumps will generate a large amount of oil mist during the vacuuming process. Direct discharge of oil mist will cause environmental pollution. Therefore, oil-sealed rotary vane vacuum pumps need to be equipped with oil mist filters.

[0003] Oil mist filters are divided into two types: external and internal. Traditional external oil mist filters have two forms, one is horizontally hung on the side of the oil storage chamber, and the other is vertically installed on the oil storage chamber. When users perform maintenance, both of the above forms require the entire filter to be removed, and the filter element to be replaced after removing the screws. Some filter elements that are difficult or impossible to remove require the entire filter to be replaced, which is inconvenient to maintain and the user experience is poor. Traditional internal oil mist filters are installed inside the oil storage chamber. Maintenance usually requires the removal of screws or the use of special tools, which is also inconvenient. Summary of the invention

[0004] The utility model aims to solve the problem that the filter element of the existing oil-sealed rotary vane vacuum pump is inconvenient to replace, and provides a filter element replacement structure. During maintenance, there is no need to remove the oil mist filter, remove screws or use special tools, and there is no need to replace the entire filter, which greatly improves the convenience of maintaining the filter element and improves user experience. The utility model also provides a vacuum pump using this filter element replacement structure.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solution: a filter element replacement structure, the filter element replacement structure comprises:

[0006] The filter housing has a filter element installation cavity, the outer end of the filter element installation cavity forms a first threaded portion, and the inner end of the filter element installation cavity has an air inlet hole;

[0007] An oil mist filter element having a second threaded portion matched with the first threaded portion of the filter housing and a control portion exposed from the filter housing;

[0008] The oil mist filter element and the filter housing are connected or separated by rotating the operating part. When the oil mist filter element is installed on the filter housing, the inner end of the oil mist filter element is sealed with the inner end of the filter element installation cavity, and the outer end of the oil mist filter element is sealed with the outer end of the filter element installation cavity.

[0009] The filter element replacement structure of the utility model comprises a filter housing and an oil mist filter element. The outer end of the filter element installation cavity of the filter housing forms a first threaded portion. The oil mist filter element has a second threaded portion that cooperates with the first threaded portion of the filter housing and an operating portion exposed to the filter housing. The oil mist filter element and the filter housing can be connected or separated by rotating the operating portion without removing threaded fasteners such as screws or using tools. The filter element is very convenient to remove and install.

[0010] As an improvement, the filter housing and the outer end of the oil mist filter element are sealed by an outer sealing ring; the filter housing and the inner end of the oil mist filter element are sealed by an inner sealing ring.

[0011] As an improvement, the outer sealing ring is compressed radially; and the inner sealing ring is compressed axially.

[0012] As an improvement, an outer sealing ring is formed at the end of the filter housing, the oil mist filter element has an outer sealing ring groove, the opening of the outer sealing ring groove is radially arranged outward, the outer sealing ring is installed in the outer sealing ring groove, and the outer sealing ring and the outer sealing ring groove radially compress the outer sealing ring and achieve sealing.

[0013] As an improvement, the outer sealing ring has a base, a radial end surface of the base is provided with a deformation groove, the radial outer side of the base extends outward to form an outer convex portion, and the radial inner side of the base extends inward to form an inner convex portion;

[0014] The projections of the outer convex portion, the inner convex portion and the deformation groove in the radial direction at least partially overlap;

[0015] The outer convex part and the inner convex part are conical;

[0016] The deformation groove is open.

[0017] As an improvement, the oil mist filter element has an inner sealing ring groove, the opening of the inner sealing ring groove is axially arranged, and the inner sealing ring is installed in the inner sealing ring groove; the inner end of the filter element mounting cavity is provided with a sealing plane, and the sealing plane and the sealing ring groove axially compress the inner sealing ring.

[0018] As an improvement, the oil mist filter element comprises a filter body, an inner end cover and an outer end cover which are assembled as one body, an air inlet is formed at the center of the filter body, the second threaded portion and the control portion are formed on the outer end cover, the inner end cover is sealed with the filter element installation cavity, the outer end cover is sealed with the filter element installation cavity, and the inner end cover has an insertion portion inserted into the air inlet hole;

[0019] The filter element installation cavity is provided with a pressure relief valve;

[0020] The filter housing is provided with an exhaust valve;

[0021] The oil mist filter element is arranged horizontally.

[0022] A vacuum pump comprises an oil tank, and the vacuum pump also comprises the aforementioned filter element replacement structure, wherein the filter housing is fixed outside the oil tank, or the oil tank forms the filter housing.

[0023] As an improvement of the vacuum pump, the filter housing is fixed outside the oil tank, the filter element installation cavity is located radially outside the oil tank, the filter housing includes an upper shell and a lower shell, the upper shell forms a transverse L-shaped airflow channel, the lower shell forms a vertical airflow channel, and the air inlet is formed on the side wall of the vertical airflow channel;

[0024] An air outlet is provided at the upper end of the oil tank, and an air outlet piece is provided in the air outlet. The air outlet piece is sealed with the oil tank and the upper shell. The air outlet piece includes an upper closed portion, a middle air hole and a plurality of side air holes. A force-bearing portion is also formed at the upper end of the air outlet piece. The air outlet piece is threadedly connected to the oil tank, a sealing ring is provided between the air outlet piece and the oil tank, and a sealing ring is provided between the air outlet piece and the filter housing.

[0025] As an improvement of the vacuum pump, the oil tank includes an oil storage chamber, and a liquid level observation structure is provided on the oil storage chamber;

[0026] An oil hole is formed on the side wall of the oil storage chamber, an observation sealing groove is formed on the periphery of the oil hole, an observation sealing ring is provided in the observation sealing groove, a transparent block is provided on the outside of the observation sealing ring, a gap is provided between the transparent block and the side wall of the oil storage chamber, a clamping block is provided on the outside of the transparent block, the clamping block is fixed to the side wall of the oil storage chamber by screws, and the clamping block is transparent or has an observation groove corresponding to the transparent block.

[0027] The beneficial effects of the filter element replacement structure of the present invention are as follows: the filter element replacement structure comprises a filter housing and an oil mist filter element, the outer end of the filter element mounting cavity of the filter housing forms a first threaded portion, the oil mist filter element comprises a second threaded portion matching the first threaded portion of the filter housing and an operating portion exposed to the filter housing, and the oil mist filter element and the filter housing can be connected or separated by rotating the operating portion without removing threaded fasteners such as screws or using tools, so that the filter element can be removed and installed very conveniently.

[0028] The vacuum pump of the utility model adopts the filter element replacement structure of the utility model and has all the beneficial effects of the filter element replacement structure of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1It is a structural schematic diagram of the vacuum pump of the first embodiment of the utility model.

[0030] Figure 2 It is a structural exploded view of the vacuum pump of the first embodiment of the present utility model.

[0031] Figure 3 and Figure 4 It is a schematic diagram of the structure of the oil mist filter of the vacuum pump of the first embodiment of the utility model at different angles.

[0032] Figure 5 and Figure 6 It is a cross-sectional view at different angles of the oil mist filter of the vacuum pump of the first embodiment of the utility model.

[0033] Figure 7 It is a structural schematic diagram of an oil mist filter element of an oil mist filter of a vacuum pump according to a first embodiment of the utility model.

[0034] Figure 8 It is a cross-sectional view of an outer sealing ring of an oil mist filter of a vacuum pump according to a first embodiment of the utility model.

[0035] Fig. 9 It is a cross-sectional view of the liquid level observation structure of the vacuum pump of the first embodiment of the present utility model.

[0036] Fig.10 It is a schematic diagram of the structure of the vacuum pump of the second embodiment of the present utility model.

[0037] Fig.11 It is a partial cross-sectional view of the vacuum pump of the second embodiment of the present utility model.

[0038] Fig.12 It is a structural schematic diagram of a bracket of an oil tank of a vacuum pump in Embodiment 2 of the present utility model.

[0039] Fig.13 It is a structural schematic diagram of the oil tank shell of the oil tank of the vacuum pump of the second embodiment of the utility model.

[0040] Fig.14 It is a structural schematic diagram of the oil mist filter element of the vacuum pump of the second embodiment of the utility model.

[0041] Fig.15 It is a schematic diagram of the structure of the vacuum pump of the third embodiment of the present utility model.

[0042] In the figure, the dotted arrows represent airflow.

[0043] In the figure, 01, oil mist filter;

[0044] 1. Filter housing; 1-1. Upper housing; 1-2. Lower housing; 11. Filter element mounting cavity; 111. Sealing plane; 12. First threaded portion; 13. Air inlet; 14. Outer sealing ring; 15. L-shaped air flow channel; 16. Vertical air flow channel;

[0045] 2. Oil mist filter element; 2-1. Filter body; 2-2. Inner end cover; 2-3. Outer end cover; 21. Second threaded portion; 22. Control portion; 23. Outer sealing ring groove portion; 24. Inner sealing ring groove portion; 25. Insertion portion;

[0046] 3. outer sealing ring; 31. base; 32. deformation groove; 33. outer convex part; 34. inner convex part;

[0047] 4. Inner sealing ring;

[0048] 5. Pressure relief valve;

[0049] 6. Exhaust valve;

[0050] 7. air outlet; 71. upper sealing portion; 72. middle air hole; 73. side air hole;

[0051] 8. Oil tank; 81. Air outlet; 82. Bracket; 821. Filter channel; 822. Pressure relief channel; 83. Oil tank shell; 84. Oil storage chamber; 85. Oil hole; 86. Observation sealing groove; 87. Transparent block; 88. Pressing block;

[0052] 9. Transparent oil cup;

[0053] 10. Oil return pipe;. DETAILED DESCRIPTION

[0054] The technical solutions of the embodiments of the present invention are explained and described below, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0055] Embodiment 1

[0056] See also Figures 1 to 9 The vacuum pump of the first embodiment of the utility model comprises an oil tank 8 and an oil mist filter 01, wherein the oil mist filter 01 comprises:

[0057] A filter housing 1, wherein the filter housing 1 is fixed outside the oil tank 8, and the filter housing 1 has a filter element installation cavity 11, wherein the outer end of the filter element installation cavity 11 forms a first threaded portion 12, and the inner end thereof forms an air inlet hole 13;

[0058] The oil mist filter element 2 has a second threaded portion 21 matched with the first threaded portion 12 of the filter housing 1 and a control portion 22 exposed from the filter housing 1;

[0059] The oil mist filter element 2 and the filter housing 1 are connected or separated by rotating the operating part 22. When the oil mist filter element 2 is installed on the filter housing 1, the inner end of the oil mist filter element 2 is sealed with the inner end of the filter element installation cavity 11, and the outer end of the oil mist filter element 2 is sealed with the outer end of the filter element installation cavity 11.

[0060] In this embodiment, the filter housing 1 and the outer end of the oil mist filter element 2 are sealed by an outer sealing ring 3 ; the filter housing 1 and the inner end of the oil mist filter element 2 are sealed by an inner sealing ring 4 .

[0061] In other embodiments, the filter housing and the outer end of the oil mist filter element may also be sealed by filling with sealant or the like.

[0062] In this embodiment, the outer sealing ring 3 is compressed radially; and the inner sealing ring 4 is compressed axially.

[0063] In this embodiment, an outer sealing ring 14 is formed at the end of the filter housing 1, and the oil mist filter element 2 has an outer sealing ring groove 23, the opening of the outer sealing ring groove 23 is radially arranged outward, and the outer sealing ring 3 is installed in the outer sealing ring groove 23, and the outer sealing ring 14 and the outer sealing ring groove 23 radially compress the outer sealing ring 3 and achieve sealing.

[0064] In this embodiment, the outer sealing ring 3 has a base 31, a deformation groove 32 is provided on the radial end surface of the base 31, the radial outer side of the base 31 extends outward to form an outer protrusion 33, and the radial inner side of the base 31 extends inward to form an inner protrusion 34;

[0065] The projections of the outer protrusion 33, the inner protrusion 34 and the deformation groove 32 in the radial direction at least partially overlap;

[0066] The outer protrusion 33 and the inner protrusion 34 are conical;

[0067] The deformation groove 32 is open. The outer sealing ring 3 adopts this structure to ensure the sealing effect while reducing the processing accuracy requirements. At the same time, the outer sealing ring 3 is radially compressed, and a large axial friction force can be generated between the outer sealing ring 3 and the filter housing 1, effectively avoiding or reducing the loosening of the oil mist filter element 2.

[0068] In other embodiments, the outer sealing ring may also be axially compressed like the inner sealing ring, but higher processing accuracy is required to ensure that both the outer sealing ring and the inner sealing ring are well compressed, and the risk of the oil mist filter element loosening will also be increased.

[0069] In this embodiment, the oil mist filter element 2 has an inner sealing ring groove 24, the opening of the inner sealing ring groove 24 is axially arranged, and the inner sealing ring 4 is installed in the inner sealing ring groove 24; the inner end of the filter element installation cavity 11 is provided with a sealing plane 111, and the sealing plane 111 and the sealing ring groove axially compress the inner sealing ring 4. The sealing plane 111 is located in the groove, and the groove where the sealing plane 111 is located can limit the radial deviation of the oil mist filter element 2.

[0070] In this embodiment, the oil mist filter element 2 includes a filter body 2-1, an inner end cover 2-2 and an outer end cover 2-3 assembled as one body, an air inlet is formed at the center of the filter body 2-1, the second threaded portion 21 and the control portion 22 are formed on the outer end cover 2-3, the inner end cover 2-2 is sealed with the filter element installation cavity 11, the outer end cover 2-3 is sealed with the filter element installation cavity 11, and the inner end cover 2-2 has an insertion portion 25 inserted into the air inlet hole 13. The air inlet hole 13 can limit the radial deviation of the insertion portion 25.

[0071] In this embodiment, the filter element mounting cavity 11 is located radially outside the oil tank 8, and the filter housing 1 includes an upper shell 1-1 and a lower shell 1-2. The upper shell 1-1 forms a transverse L-shaped airflow channel 15, and the lower shell 1-2 forms a vertical airflow channel 16. The air inlet 13 is formed on the side wall of the vertical airflow channel 16.

[0072] In this embodiment, a pressure relief valve 5 is provided on the filter element installation cavity 11 , and the pressure relief valve 5 is installed on the L-shaped air flow channel 15 .

[0073] In this embodiment, the filter housing 1 is provided with an exhaust valve 6 , which is installed at the upper part of the filter housing 1 .

[0074] In this embodiment, an air outlet 81 is provided at the upper end of the oil tank 8, and an air outlet piece 7 is provided in the air outlet hole 81. The air outlet piece 7 is sealed with the oil tank 8 and the upper shell 1-1. The air outlet piece 7 includes an upper closed portion 71, a middle air hole 72 and a plurality of side air holes 73. A force-bearing portion is also formed at the upper end of the air outlet piece 7. The air outlet piece 7 is threadedly connected to the oil tank 8. A sealing ring is provided between the air outlet piece 7 and the oil tank 8, and a sealing ring is provided between the air outlet piece 7 and the filter housing 1.

[0075] In this embodiment, the oil mist filter element 2 is arranged horizontally, and the air outlet 81 is arranged vertically.

[0076] See also Fig. 9 In this embodiment, the oil tank 8 includes an oil storage chamber 84, and a liquid level observation structure is provided on the oil storage chamber 84.

[0077] In this embodiment, an oil hole 85 is formed on the side wall of the oil storage chamber 84, and an observation sealing groove 86 is formed on the periphery of the oil hole 85. An observation sealing ring is provided in the observation sealing groove 86, and a transparent block 87 is provided on the outside of the observation sealing ring. There is a gap between the transparent block 87 and the side wall of the oil storage chamber 84, and a clamping block 88 is provided on the outside of the transparent block 87. The clamping block 88 is fixed to the side wall of the oil storage chamber 84 by screws, and the clamping block 88 is transparent or has an observation groove corresponding to the transparent block 87.

[0078] In this embodiment, an oil return pipe 10 is provided at the bottom of the filter housing 1 .

[0079] In this embodiment, when maintaining the oil mist filter 01, it is only necessary to rotate the operating control part 22 with a finger to release the second threaded part 21 from the first threaded part 21, and then the oil mist filter element 2 can be horizontally moved to separate the oil mist filter element 2 from the filter housing 1, and then the removed oil mist filter element 2 can be cleaned or replaced with a new oil mist filter element 2; when installing, it is only necessary to align the oil mist filter element 2 with the filter element installation cavity 11 and move the oil mist filter element 2 horizontally. When the second threaded part 21 of the oil mist filter element 2 moves to the position of the first threaded part 12 of the filter housing 1, rotate the oil mist filter element 2 so that the second threaded part 21 of the oil mist filter element 2 is threadedly connected with the first threaded part 12 of the filter housing 1, and tighten the oil mist filter element 2 to complete the installation.

[0080] In this embodiment, the working principle of the oil mist filter 01 of the vacuum pump is as follows: the oil-containing gas generated in the oil tank 8 flows into the L-shaped air flow channel 15 through the middle air hole 72 and multiple side air holes 73 of the air outlet member 7, and then enters the interior of the oil mist filter element 2 through the vertical air flow channel 16 and the insertion portion 25 in the air inlet hole 13, and the filtered gas is discharged from the exhaust valve 6. When the gas pressure in the L-shaped air flow channel 15 is too high, part of the gas will enter between the oil mist filter element 2 and the filter housing 1 from the pressure relief valve 5 on the L-shaped air flow channel 15.

[0081] The vacuum pump of the first embodiment of the utility model has the following beneficial effects: it includes a filter element replacement structure, the filter element replacement structure includes a filter housing 1 and an oil mist filter element 2, the outer end of the filter element installation cavity 11 of the filter housing 1 forms a first threaded portion 12, the oil mist filter element 2 has a second threaded portion 21 that matches the first threaded portion 12 of the filter housing 1 and an operating portion 22 exposed to the filter housing 1, and the oil mist filter element 2 and the filter housing 1 can be connected or separated by rotating the operating portion 22, without removing threaded fasteners such as screws, and without the use of tools, so that the removal and installation of the filter element are very convenient; the filter housing 1 and the outer end of the oil mist filter element 2 are connected by an outer sealing ring 3 Sealing: the filter housing 1 and the inner end of the oil mist filter element 2 are sealed by an inner sealing ring 4, the outer sealing ring 3 is radially compressed, and the inner sealing ring 4 is axially compressed. The outer sealing ring 3 has a base 31, and a deformation groove 32 is provided on the radial end face of the base 31. The radial outer side of the base 31 extends outward to form an outer protrusion 33, and the radial inner side of the base 31 extends inward to form an inner protrusion 34, which ensures the sealing effect while reducing the processing accuracy requirements, and effectively avoids or reduces the loosening of the oil mist filter element 2; a pressure relief valve 5 and an exhaust valve 6 are provided; a liquid level observation structure is provided; the external filter is located on the radial side of the oil tank 8 to save height and length.

[0082] Embodiment 2

[0083] See also Figures 10 to 14 The difference between the vacuum pump of the second embodiment of the present invention and the vacuum pump of the first embodiment is that the oil mist filter 01 is a built-in type.

[0084] In this embodiment, the vacuum pump includes an oil tank 8 and an oil mist filter 01, and the oil mist filter 01 includes:

[0085] A filter housing 1, wherein the filter housing 1 is formed by the oil tank 8, and the filter housing 1 has a filter element installation cavity 11, wherein the outer end of the filter element installation cavity 11 forms a first threaded portion 12, and the inner end thereof is provided with an air inlet hole 13;

[0086] The oil mist filter element 2 has a second threaded portion 21 matched with the first threaded portion 12 of the filter housing 1 and a control portion 22 exposed from the filter housing 1;

[0087] The oil mist filter element 2 and the filter housing 1 are connected or separated by rotating the operating part 22. When the oil mist filter element 2 is installed on the filter housing 1, the inner end of the oil mist filter element 2 is sealed with the inner end of the filter element installation cavity 11, and the outer end of the oil mist filter element 2 is sealed with the outer end of the filter element installation cavity 11.

[0088] In this embodiment, the oil tank 8 includes a bracket 82 and an oil tank shell 83 fixed by screws, and the bracket 82 and the oil tank shell 83 are sealed by a sealing ring.

[0089] In this embodiment, a filter channel 821 and a pressure relief channel 822 are formed in the oil tank 8. The filter channel 821 and the pressure relief channel 822 are independent of each other. The filter channel 821 is connected to the inside of the oil mist filter element 2, and a pressure relief valve 5 is provided in the pressure relief channel 822.

[0090] In this embodiment, the structure of the pressure relief valve 5 is the same as that in the first embodiment.

[0091] In this embodiment, the operation of replacing the oil mist filter element 2 is the same as that in the first embodiment.

[0092] In this embodiment, the working principle of filtering oil mist of the vacuum pump is as follows: the oil-containing gas generated in the oil tank 8 enters the oil mist filter element 2 through the filter channel 821 and the inserting portion 25 in the air inlet 13, and the filtered gas is discharged from the exhaust valve 6. When the gas pressure in the pressure relief channel 822 is too high, the gas will enter between the oil mist filter element 2 and the oil tank housing 83 from the pressure relief valve 5 on the pressure relief channel 822, so that the gas pressure entering the oil mist filter element 2 is kept within the allowable range.

[0093] In this embodiment, the oil mist filter element 2 is arranged in the oil tank 8, which is more beautiful than an external arrangement.

[0094] Embodiment 3

[0095] The difference between the third embodiment and the first embodiment lies in the oil return structure.

[0096] See also Fig.15 In this embodiment, a transparent oil cup 9 is provided at the bottom of the filter housing 1, and an oil return pipe 10 is provided at the bottom of the transparent oil cup 9, and the oil return pipe 10 is connected to the inside of the oil tank 8. The transparent oil cup 9 can be made of transparent plastic. The transparent oil cup 9 makes the oil level line visible.

[0097] The above is only a specific implementation of the invention, but the protection scope of the invention is not limited thereto. Those skilled in the art should understand that the invention includes but is not limited to the contents described in the above specific implementation. Any modification that does not deviate from the functional and structural principles of the invention will be included in the scope of the claims.

Claims

1. Filter element replacement structure, characterized by: The filter element replacement structure comprises: A filter housing (1) has a filter element installation cavity (11), wherein the outer end of the filter element installation cavity (11) forms a first threaded portion (12), and the inner end is provided with an air inlet hole (13); An oil mist filter element (2) comprising a second threaded portion (21) matched with the first threaded portion (12) of the filter housing (1) and a control portion (22) exposed outside the filter housing (1); The oil mist filter element (2) and the filter housing (1) are connected or disconnected by rotating the operating portion (22); when the oil mist filter element (2) is installed on the filter housing (1), the inner end of the oil mist filter element (2) is sealed with the inner end of the filter element installation cavity (11), and the outer end of the oil mist filter element (2) is sealed with the outer end of the filter element installation cavity (11).

2. The filter element replacement structure according to claim 1, characterized in that: The filter housing (1) and the outer end of the oil mist filter element (2) are sealed via an outer sealing ring (3); and the filter housing (1) and the inner end of the oil mist filter element (2) are sealed via an inner sealing ring (4).

3. The filter element replacement structure according to claim 2, characterized in that: The outer sealing ring (3) is compressed radially; and the inner sealing ring (4) is compressed axially.

4. The filter element replacement structure according to claim 3, characterized in that: An outer sealing ring (14) is formed at the end of the filter housing (1), the oil mist filter element (2) has an outer sealing ring groove (23), the opening of the outer sealing ring groove (23) is radially arranged outward, the outer sealing ring (3) is installed in the outer sealing ring groove (23), and the outer sealing ring (14) and the outer sealing ring groove (23) radially compress the outer sealing ring (3) to achieve sealing.

5. The filter element replacement structure according to claim 3, characterized in that: The outer sealing ring (3) comprises a base (31), a radial end surface of the base (31) is provided with a deformation groove (32), the radial outer side of the base (31) extends outward to form an outer protrusion (33), and the radial inner side of the base (31) extends inward to form an inner protrusion (34); The projections of the outer protrusion (33), the inner protrusion (34) and the deformation groove (32) in the radial direction at least partially overlap; The outer protrusion (33) and the inner protrusion (34) are conical; The deformation groove (32) is open.

6. The filter element replacement structure according to claim 3, characterized in that: The oil mist filter element (2) has an inner sealing ring groove (24), the opening of the inner sealing ring groove (24) is axially arranged, and the inner sealing ring (4) is installed in the inner sealing ring groove (24); the inner end of the filter element installation cavity (11) is provided with a sealing plane (111), and the sealing plane (111) and the sealing ring groove axially compress the inner sealing ring (4).

7. The filter element replacement structure according to claim 1, characterized in that: The oil mist filter element (2) comprises a filter body (2-1), an inner end cover (2-2) and an outer end cover (2-3) which are assembled as one body, an air inlet is formed at the center of the filter body (2-1), the second threaded portion (21) and the control portion (22) are formed on the outer end cover (2-3), the inner end cover (2-2) and the filter element installation cavity (11) are sealed, the outer end cover (2-3) and the filter element installation cavity (11) are sealed, and the inner end cover (2-2) has an insertion portion (25) inserted into the air inlet hole (13); The filter element installation cavity (11) is provided with a pressure relief valve (5); The filter housing (1) is provided with an exhaust valve (6).

8. A vacuum pump, comprising an oil tank (8), characterized in that: The vacuum pump further comprises a filter element replacement structure as claimed in any one of claims 1 to 7, wherein the filter housing (1) is fixed outside the oil tank (8), or the oil tank (8) forms the filter housing (1).

9. The vacuum pump according to claim 8, characterized in that: The filter housing (1) is fixed outside the oil tank (8), the filter element mounting cavity (11) is located radially outside the oil tank (8), the filter housing (1) comprises an upper housing (1-1) and a lower housing (1-2), the upper housing (1-1) forms a transverse L-shaped airflow channel (15), the lower housing (1-2) forms a vertical airflow channel (16), and the air inlet (13) is formed on a side wall of the vertical airflow channel (16); An air outlet hole (81) is provided at the upper end of the oil tank (8), an air outlet piece (7) is provided in the air outlet hole (81), the air outlet piece (7) is sealed with the oil tank (8) and the upper shell (1-1), the air outlet piece (7) comprises an upper closed portion (71), a middle air hole (72) and a plurality of side air holes (73), a force-bearing portion is also formed at the upper end of the air outlet piece (7), the air outlet piece (7) is threadedly connected to the oil tank (8), a sealing ring is provided between the air outlet piece (7) and the oil tank (8), and a sealing ring is provided between the air outlet piece (7) and the filter housing (1); A transparent oil cup is provided at the bottom of the filter housing (1), and an oil return pipe is provided at the bottom of the transparent oil cup.

10. The vacuum pump according to claim 8, characterized in that: The oil tank (8) forms the filter housing (1), the oil tank (8) comprises a bracket (82) and an oil tank housing (83) fixed by screws, the bracket (82) and the oil tank housing (83) being sealed by a sealing ring; a filter channel (821) and a pressure relief channel (822) are formed in the oil tank (8), the filter channel (821) and the pressure relief channel (822) being independent of each other, the filter channel (821) being connected to the interior of the oil mist filter element (2), and a pressure relief valve (5) being provided in the pressure relief channel (822); The oil tank (8) comprises an oil storage chamber (84), a liquid level observation structure is provided on the oil storage chamber (84), an oil hole (85) is provided on the side wall of the oil storage chamber (84), an observation sealing groove (86) is formed on the periphery of the oil hole (85), an observation sealing ring is provided in the observation sealing groove (86), a transparent block (87) is provided on the outside of the observation sealing ring, a gap is provided between the transparent block (87) and the side wall of the oil storage chamber (84), a clamping block (88) is provided on the outside of the transparent block (87), the clamping block (88) is fixed to the side wall of the oil storage chamber (84) by screws, and the clamping block (88) is transparent or has an observation groove corresponding to the transparent block (87).

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