Porous separation filter element capable of efficiently filtering

Abstract

The invention provides an efficient filtering porous separation filter element which comprises a hollow dust falling cavity formed by the center of a dust cup and the peripheral side walls, a conical mounting boss is arranged in the center of the bottom of the dust falling cavity, an air inlet is formed in the outer side wall of the center of the dust cup and communicated with the dust falling cavity, and the filter element is arranged in the dust falling cavity. The filter element sequentially comprises a fine dust falling cone, a porous separation cone lower cover plate, a secondary porous filter sleeve, a fixed disc and a primary filter sleeve from bottom to top; the dust cup cover is arranged at the top of the filter element, the dust cup cover is arranged on the outer side of the fixed disc in a rotating and clamping type sleeving mode, a handle is arranged at the top of the dust cup cover, and an air outlet is formed in the outer side wall of one side of the dust cup cover. Therefore, the cleaning time of the product in single use is prolonged, the filtering efficiency and the cleaning effect are improved, the cleaning frequency is reduced, and the service life is effectively prolonged.

Description

Technical Field

[0001] The invention relates to the field of upright vacuum cleaners, in particular to the technical field of vacuum cleaner filter elements, and specifically to a porous separation filter element with high efficiency filtration. Background Art

[0002] Most upright vacuum cleaners now use single-cone filtration. When the vacuum cleaner inhales dusty air, the single-cone filter will generate a rotating airflow, causing the dust to be thrown outward under the action of centrifugal force and fall into the dust collection bucket. However, since there is only one cyclone structure, some fine dust may not be completely separated, resulting in a slightly poor filtering effect. Summary of the invention

[0003] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a porous separation filter element with high efficiency filtration, so as to solve the difficulties of the prior art.

[0004] In order to achieve the above-mentioned and other related purposes, the present invention provides a porous separation filter element for high-efficiency filtration, comprising:

[0005] A dust cup 1, wherein the center of the dust cup 1 and the surrounding side walls form a hollow dust chamber 11, a conical mounting boss 12 is provided in the center of the bottom of the dust chamber 11, and an air inlet 13 is provided on the outer side wall in the center of the dust cup 1, and the air inlet 13 is communicated with the dust chamber 11;

[0006] The filter element 2 is arranged in the dust collection chamber 11, and the bottom of the filter element 2 is sleeved on the outside of the conical mounting boss 12. The filter element 2 is composed of a fine dust collection cone 21, a porous separation cone lower cover plate 22, a secondary porous filter sleeve 23, a fixing plate 24 and a primary filter sleeve 25 from bottom to top;

[0007] The dust cup cover 3 is arranged on the top of the filter element 2, and the dust cup cover 3 is screwed onto the outside of the fixed plate 24. A handle 31 is arranged on the top of the dust cup cover 3, and an exhaust port 32 is arranged on the outer side wall of one side of the dust cup cover 3.

[0008] According to a preferred embodiment, the fine dust collection cone 21 is arranged in the dust collection chamber 11, and the fine dust collection cone 21 includes from bottom to top: a hollow circular tube 211, a hollow conical tube 212 and an inner bottom plate 213. The bottom of the hollow circular tube 211 is sleeved on the top of the conical mounting boss 12, and a hollow conical tube 212 is passed through the top of the hollow circular tube 211. The inner diameter of the top of the hollow conical tube 212 is larger than the inner diameter of the bottom. The hollow conical tube 212 is communicated with the hollow circular tube 211, and an inner bottom plate 213 is sleeved on the outer side wall of the bottom of the hollow conical tube 212, and the outer side of the bottom end of the inner bottom plate 213 is a groove 214.

[0009] According to a preferred embodiment, the hollow circular tube 211, the hollow conical tube 212 and the inner bottom plate 213 are integrally constructed.

[0010] According to a preferred embodiment, the top of the porous separation cone lower cover plate 22 is a convex arc surface, and the porous separation cone lower cover plate 22 is connected to the top of the hollow cone tube 212 by bolts. A plurality of dust collection holes 221 are evenly spaced on the top of the porous separation cone lower cover plate 22, and the bottom of the dust collection hole 221 is connected to the hollow cone tube 212.

[0011] According to a preferred embodiment, the secondary porous filter sleeve 23 is arranged directly above the fine dust collection cone 21, and the secondary porous filter sleeve 23 includes several separation vertebral tubes 231 arranged in an array, each of the separation vertebral tubes 231 is connected to each other, and the bottoms of several separation vertebral tubes 231 are sequentially clamped in the dust collection holes 221, and a guide channel 232 is opened on the side of the top of the separation vertebral tube 231 away from the central axis of the porous separation cone lower cover plate 22, and an inlet 233 is opened at the bottom of the guide channel 232 in several of the separation vertebral tubes 231 close to the central axis of the porous separation cone lower cover plate 22.

[0012] According to a preferred embodiment, the inner diameter of the top of the separated spinal canal 231 is greater than the inner diameter of the bottom.

[0013] According to a preferred embodiment, all separated spinal canals 231 in the secondary porous filter sleeve 23 are of an integrated structure.

[0014] According to the preferred embodiment, the fixed disk 24 is covered on the top of the secondary porous filter sleeve 23, the top of the fixed disk 24 is concave, and the bottom of the fixed disk 24 is provided with several guide tubes 241 arranged according to the separation vertebral canal 231. The guide tubes 241 extend vertically downward into the separation vertebral canal 231, and a sealing layer 26 is provided between the fixed disk 24 and the secondary porous filter sleeve 23.

[0015] According to the preferred embodiment, a long rod screw 242 is passed through the middle of the fixed disk 24, and the bottom of the long rod screw 242 passes through the fixed disk 24 and the secondary porous filter sleeve 23 in sequence and is clamped in the porous separation cone lower cover 22. Square grooves 243 are opened around the fixed disk 24.

[0016] According to a preferred embodiment, the fixed plate 24 , the secondary porous filter sleeve 23 and the porous separation cone lower cover plate 22 are connected by long rod screws 242 .

[0017] According to a preferred embodiment, the top taking side of the first-level filter sleeve 25 is columnar, and protrusions 251 are provided on the outer walls around the first-level filter sleeve 25, and the protrusions 251 are clamped in the square groove 243. The top of the first-level filter sleeve 25 is clamped between the fixed plate 24 and the secondary porous filter sleeve 23. The bottom filtering side of the first-level filter sleeve 25 is conical, and a closed ring 252 is provided on the inner wall of the bottom of the first-level filter sleeve 25. The top of the closed ring 252 is set at the bottom of the inner bottom plate 213, and the top of the closed ring 252 is clamped in the groove 214. Filter holes 253 are opened at equal intervals on the outer wall of the bottom filtering side of the first-level filter sleeve 25, and the bottom end of the filter hole 253 is flush with the top of the inner bottom plate 213.

[0018] According to a preferred embodiment, a sealing ring 254 is provided at the bottom of the top taking-up side of the first-level filter sleeve 25 , and the outer wall of the sealing ring 254 is in close contact with the inner wall of the dust cup 1 .

[0019] The present invention adopts a fine dust collection cone, a porous separation cone lower cover, a secondary porous filter sleeve, a fixed plate and a primary filter sleeve. The present invention designs a primary filter sleeve and a secondary porous filter sleeve in the filter element. The two filtering and separation units can filter most of the garbage, reducing the pressure on the next filtering link, thereby increasing the cleaning time of the product for a single use, improving the filtering efficiency and cleaning effect, reducing the cleaning frequency, and effectively extending the service life.

[0020] The best embodiment for carrying out the present invention will be described in more detail below with reference to the accompanying drawings so that the features and advantages of the present invention can be easily understood. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Shown is a three-dimensional structural schematic diagram of the filter element and the dust cup cover in the present invention;

[0022] Figure 2 Shown is a schematic diagram of the assembly of the filter element and the dust cup of the present invention;

[0023] Figure 3 Shown is an enlarged schematic diagram of the three-dimensional structure of the dust cup in the present invention;

[0024] Figure 4 Shown is a cross-sectional schematic diagram of the present invention;

[0025] Figure 5 Shown is an enlarged schematic diagram of the three-dimensional structure of the filter element in the present invention;

[0026] Figure 6 Shown is an enlarged schematic diagram of the three-dimensional structure of the secondary porous filter sleeve in the present invention;

[0027] Figure 7 Shown is an enlarged schematic diagram of the three-dimensional structure of the fixed disk in the present invention;

[0028] Figure 8 It shows an enlarged schematic diagram of the three-dimensional structure of the fine dust falling cone in the present invention;

[0029] Fig. 9 Shown is an enlarged schematic diagram of the three-dimensional structure of the first-level filter sleeve in the present invention;

[0030] Fig.10 It is an enlarged schematic diagram of the three-dimensional structure of the porous separation cone lower cover plate in the present invention;

[0031] Description of symbols

[0032] 1. Dust cup; 11. Dust chamber; 12. Conical mounting boss; 13. Air inlet;

[0033] 2. Filter element;

[0034] 21. dust cone for fine dust; 211. hollow circular tube; 212. hollow conical tube; 213. inner bottom plate; 214. groove;

[0035] 22. Multi-hole separation cone lower cover plate; 221. Dust removal hole;

[0036] 23. Secondary porous filter sleeve; 231. Separation spinal canal; 232. Diversion channel; 233. Inlet;

[0037] 24, fixing plate; 241, flow guide tube; 242, long rod screw; 243, square groove;

[0038] 25. primary filter sleeve; 251. convex block; 252. closing ring; 253. filter hole; 254. sealing ring;

[0039] 26. Sealing layer;

[0040] 3. Dust cup cover; 31. Handle; 32. Exhaust vent; DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the drawings of specific embodiments of the present invention. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Compared to the embodiments shown in the drawings, feasible embodiments within the scope of the present invention may have fewer components, other components not shown in the drawings, different components, differently arranged components, or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0043] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not necessarily indicate a quantity limitation. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0044] The present invention provides a porous separation filter element with high efficiency filtration, which is used in the filter element design process of an upright vacuum cleaner. In the present invention, the fine dust collection cone 21, the porous separation cone lower cover plate 22, the secondary porous filter sleeve 23, the fixed plate 24 and the primary filter sleeve 25 are particularly suitable for use in an upright vacuum cleaner.

[0045] In general, the porous separation filter element for high efficiency filtration proposed in the present invention mainly comprises: a fine dust falling cone 21, a porous separation cone lower cover plate 22, a secondary porous filter sleeve 23, a fixing plate 24 and a primary filter sleeve 25, wherein, see Figure 1 , which shows the arrangement relationship of the fine dust collection cone 21, the porous separation cone lower cover plate 22, the secondary porous filter sleeve 23, the fixed plate 24 and the primary filter sleeve 25.

[0046] When the high-efficiency filtration porous separation filter element proposed by the present invention is in use, dust and wind enter from the air inlet 13 of the dust cup 1, and the larger garbage in the dust is intercepted by the filter holes 253 in the first-level filter sleeve 25. The wind flow containing small particles of dust goes up along the fine dust falling cone 21 and the outer wall of the second-level porous filter sleeve 23, and respectively enters the multiple hollow cone tubes 212 in the second-level porous filter sleeve 23. The wind flow forms a cyclone between the inner wall of the fine dust falling cone 21 and the outer wall of the guide tube 241, and falls away from the dust. The cyclone goes down along the outer wall of the guide tube 241, and the filtered wind flow enters the dust cup cover 3 from the guide tube 241 and is discharged from the exhaust port 32. When new airflow enters the primary filter sleeve 25, the larger garbage outside the primary filter sleeve 25 will fall into the bottom of the dust cup cover 3, and the dust in the hollow cone tube 212 will enter the fine dust collection cone 21. When cleaning and maintenance is needed, the filter element 2 can be taken out from the dust cup cover 3 by rotating and pulling the dust cup cover 3, and the dust in the fine dust collection cone 21 will fall into the dust cup 1, which is convenient for cleaning. The present invention designs a primary filter sleeve 25 and a secondary porous filter sleeve 23 in the filter element. The two filtering and separation units can filter most of the garbage, reducing the pressure on the next filtering link, thereby increasing the cleaning time of the product for a single use, improving the filtering efficiency and cleaning effect, reducing the cleaning frequency, and effectively extending the service life.

[0047] The fine dust falling cone 21 is arranged in the dust falling chamber 11. The fine dust falling cone 21 includes from bottom to top: a hollow circular tube 211 and a hollow conical tube 212. The bottom of the hollow circular tube 211 is sleeved on the top of the conical mounting boss 12. The top of the hollow circular tube 211 is penetrated by a hollow conical tube 212. The inner diameter of the top of the hollow conical tube 212 is greater than the inner diameter of the bottom. The hollow conical tube 212 is connected to the hollow circular tube 211. The hollow circular tube 211 and the hollow conical tube 212 form a channel that is wide at the top and narrow at the bottom. After the fine dust falls in, it stays in the cone. The hollow conical tube 212 has a bottom portion and will not rise up to interfere with the filtration of the secondary porous filter sleeve 23. An inner bottom plate 213 is sleeved on the outer wall of the bottom of the hollow conical tube 212. The outer side of the bottom end of the inner bottom plate 213 is a groove 214. The groove 214 reduces the assembly gap between the primary filter sleeve 25 and the hollow circular tube 211, the hollow conical tube 212 and the inner bottom plate 213 are an integrated structure with stronger strength, which reduces the difficulty of disassembly during cleaning and maintenance. There will be no assembly gap, which saves assembly time in the production process and has lower batch processing costs.

[0048] The top of the porous separation cone lower cover 22 is a raised arc surface. The structure of the raised arc surface can facilitate the upward airflow and the sliding of accumulated dust, thereby reducing the number of cleaning times. The porous separation cone lower cover 22 is connected to the top of the hollow cone tube 212 by bolts. A number of dust collection holes 221 are evenly spaced at the top of the porous separation cone lower cover 22, and the bottom of the dust collection hole 221 is connected to the hollow cone tube 212.

[0049] The above-mentioned secondary porous filter sleeve 23 is arranged directly above the fine dust collection cone 21. The secondary porous filter sleeve 23 includes several separated spinal tubes 231 arranged in an array. Each separation spinal tube 231 is connected to each other. The bottoms of several separation spinal tubes 231 are sequentially stuck in the dust collection holes 221. A guide channel 232 is opened on the side of the top of the separation spinal tube 231 away from the central axis of the porous separation cone lower cover plate 22. An inlet 233 is opened at the bottom of the guide channel 232 in several separation spinal tubes 231 close to the central axis of the porous separation cone lower cover plate 22. The inlet 233 enables the fine dust collection cone 21 located in the middle of the secondary porous filter sleeve 23 to also divert the incoming air. It should also be noted that all the separation spinal tubes 231 in the secondary porous filter sleeve 23 are of an integrated structure, which reduces the difficulty of disassembly during cleaning and maintenance, and can be formed by injection molding, with low processing cost.

[0050] The wind flows along the first-level filter sleeve 25 into the second-level porous filter sleeve 23 from the small space into the large space, and the air inlet area of ​​the filter hole 253 in the first-level filter sleeve 25 is smaller than the inner wall area of ​​the separation vertebral canal 231 in the second-level porous filter sleeve 23. The wind flows into the second-level porous filter sleeve 23 and is diverted by the separation vertebral canal 231 while the wind speed is reduced, which is beneficial to dust collection. After the wind flows into the separation vertebral canal 231, there is a height difference between the bottom end of the guide tube 241 and the bottom end of the guide channel 232, and the height of the guide tube 241 is lower than the guide channel 232. The wind needs to flow axially downward between the outer wall of the separation vertebral canal 231 and the inner wall of the separation vertebral canal 231. At the same time, because the wind flow poured into the guide channel 232 is radial, a cyclone will be formed in the separation vertebral canal 231 to achieve centrifugal dust collection.

[0051] The above-mentioned fixed disk 24 is covered on the top of the secondary porous filter sleeve 23, and a plurality of guide tubes 241 are arranged at the bottom of the fixed disk 24 according to the separation vertebral canal 231. The guide tubes 241 extend vertically downward into the separation vertebral canal 231. A sealing layer 26 is arranged between the fixed disk 24 and the secondary porous filter sleeve 23. The sealing layer 26 seals the fixed disk 24 and the secondary porous filter sleeve 23. A long rod screw 242 is passed through the middle of the fixed disk 24. The bottom of the long rod screw 242 passes through the fixed disk 24 and the secondary porous filter sleeve 23 in turn and is clamped in the porous separation cone lower cover 22, which simplifies the internal installation structure, makes the interior of the filter element 2 relatively clean and tidy, and makes the air duct smoother and dust-free. Square grooves 243 are opened around the fixed disk 24.

[0052] The top of the first-level filter sleeve 25 is columnar, and a protrusion 251 is arranged on the outer wall around the first-level filter sleeve 25. The top of the first-level filter sleeve 25 is clamped between the fixed plate 24 and the second-level porous filter sleeve 23, and the protrusion 251 is clamped in the square groove 243, so that the fixed plate 24 and the first-level filter sleeve 25 adopt a snap connection structure, which is simple to assemble, improves production efficiency, is more environmentally friendly and saves materials, and the bottom filtering side of the first-level filter sleeve 25 is conical. The inner side of the bottom of the first-level filter sleeve 25 A closed ring 252 is arranged on the wall, and the top of the closed ring 252 is arranged at the bottom of the inner bottom plate 213. The top of the closed ring 252 is clamped in the groove 214. Filter holes 253 are opened at equal intervals on the outer wall of the filter side of the bottom of the first-level filter sleeve 25. The bottom end of the filter hole 253 is flush with the top of the inner bottom plate 213. A sealing ring 254 is arranged on the bottom sleeve of the top taking side of the first-level filter sleeve 25. The outer wall of the sealing ring 254 is tightly attached to the inner wall of the dust cup 1. The sealing ring 254 prevents wind flow from entering the top of the dust cup 1.

[0053] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A porous separation filter element for high efficiency filtration, characterized in that: include: A dust cup (1), wherein the dust cup (1) is provided with a hollow dust-falling cavity (11) in the middle and surrounding side walls, a conical mounting boss (12) is provided in the middle of the bottom of the dust-falling cavity (11), an air inlet (13) is provided on the outer side wall in the middle of the dust cup (1), and the air inlet (13) is communicated with the dust-falling cavity (11); A filter element (2), the filter element (2) being arranged in the dust collection chamber (11), the bottom of the filter element (2) being sleeved on the outside of the conical mounting boss (12), the filter element (2) comprising, from bottom to top, a fine dust collection cone (21), a porous separation cone lower cover plate (22), a secondary porous filter sleeve (23), a fixing plate (24) and a primary filter sleeve (25); A dust cup cover (3), wherein the dust cup cover (3) is arranged on the top of the filter element (2), the dust cup cover (3) is screwed onto the outside of the fixed plate (24), a handle (31) is arranged on the top of the dust cup cover (3), and an exhaust port (32) is arranged on the outer side wall of one side of the dust cup cover (3).

2. The porous separation filter element for high efficiency filtration according to claim 1, characterized in that: The fine dust collection cone (21) is arranged in the dust collection cavity (11), and the fine dust collection cone (21) comprises, from bottom to top: a hollow circular tube (211), a hollow conical tube (212) and an inner bottom plate (213); the bottom of the hollow circular tube (211) is sleeved on the top of the conical mounting boss (12); the top of the hollow circular tube (211) is penetrated by a hollow conical tube (212); the inner diameter of the top of the hollow conical tube (212) is greater than the inner diameter of the bottom; the hollow conical tube (212) is communicated with the hollow circular tube (211); the inner bottom plate (213) is sleeved on the outer side wall of the bottom of the hollow conical tube (212); the outer side of the bottom end of the inner bottom plate (213) is a groove (214).

3. The porous separation filter element for high efficiency filtration according to claim 2, characterized in that: The hollow circular tube (211), the hollow conical tube (212) and the inner bottom plate (213) are of an integrated structure.

4. The porous separation filter element for high efficiency filtration according to claim 3, characterized in that: The top of the porous separation cone lower cover plate (22) is a convex arc surface. The porous separation cone lower cover plate (22) is connected and covered on the top of the hollow cone tube (212) by bolt connection. The top of the porous separation cone lower cover plate (22) is provided with a plurality of dust collection holes (221) at equal intervals, and the bottoms of the dust collection holes (221) are in communication with the hollow cone tube (212).

5. The porous separation filter element for high efficiency filtration according to claim 4, characterized in that: The secondary porous filter sleeve (23) is arranged directly above the fine dust collection cone (21), and the secondary porous filter sleeve (23) includes a plurality of separation spinal tubes (231) arranged in an array, each of the separation spinal tubes (231) is connected to each other, and the bottoms of the plurality of separation spinal tubes (231) are sequentially clamped in the dust collection holes (221), and a guide channel (232) is provided on the side of the top of the separation spinal tube (231) away from the central axis of the porous separation cone lower cover plate (22), and an inlet (233) is provided at the bottom of the guide channel (232) in the plurality of separation spinal tubes (231) close to the central axis of the porous separation cone lower cover plate (22).

6. The porous separation filter element for high efficiency filtration according to claim 5, characterized in that: All separated spinal tubes (231) in the secondary porous filter sleeve (23) are of an integrated structure.

7. The porous separation filter element for high efficiency filtration according to claim 6, characterized in that: All separated spinal tubes (231) in the secondary porous filter sleeve (23) are of an integrated structure.

8. The porous separation filter element for high efficiency filtration according to claim 7, characterized in that: The fixing plate (24) is covered on the top of the secondary porous filter sleeve (23); the top of the fixing plate (24) is a concave surface; the bottom of the fixing plate (24) is provided with a plurality of flow guide tubes (241) arranged according to the separation vertebral canal (231); the flow guide tubes (241) extend vertically downward into the separation vertebral canal (231); and a sealing layer (26) is provided between the fixing plate (24) and the secondary porous filter sleeve (23).

9. The porous separation filter element for high efficiency filtration according to claim 8, characterized in that: A long-rod screw (242) is inserted in the middle of the fixed disk (24), and the bottom of the long-rod screw (242) passes through the fixed disk (24) and the secondary porous filter sleeve (23) in sequence and is clamped in the porous separation cone lower cover (22). Square grooves (243) are provided around the fixed disk (24).

10. The porous separation filter element for high efficiency filtration according to claim 9, characterized in that: The top taking side of the primary filter sleeve (25) is columnar, and the outer side walls around the primary filter sleeve (25) are provided with protrusions (251), and the protrusions (251) are clamped in the square groove (243). The top of the primary filter sleeve (25) is clamped between the fixed plate (24) and the secondary porous filter sleeve (23). The bottom filtering side of the primary filter sleeve (25) is conical, and the inner side wall of the bottom of the primary filter sleeve (25) is provided with a closed ring (252), and the top of the closed ring (252) is arranged at the bottom of the inner bottom plate (213), and the top of the closed ring (252) is clamped in the groove (214). The outer side wall of the bottom filtering side of the primary filter sleeve (255) is provided with filtering holes (253) at equal intervals, and the bottom ends of the filtering holes (253) are flush with the top end of the inner bottom plate (213).

11. The porous separation filter element for high efficiency filtration according to claim 10, characterized in that: The bottom sleeve of the top taking-up side of the primary filter sleeve (25) is provided with a sealing ring (254), and the outer wall of the sealing ring (254) is in close contact with the inner wall of the dust cup (1).

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