Filter paper cartridge structure, cylindrical air filter element and filter element manufacturing process

Abstract

The present invention discloses a filter paper drum structure, a cylindrical air filter element and a filter element manufacturing process. The filter paper drum is made by repeatedly folding filter paper into a wave shape and then forming a cylindrical shape. It has a plurality of folding surfaces in the circumferential direction. There is an outer folding spacing or an inner folding spacing with one side opening between adjacent folding surfaces. A plurality of transverse partitions are arranged in the inner folding spacing and in the axial direction. The transverse partitions are radially supported between adjacent folding surfaces. The plurality of rubber insulation layers of the present invention divide the filter paper drum into a plurality of filter sections. Due to the restriction and guiding effect of the rubber insulation layers, the air flow is diverted to a plurality of filter sections for filtration, so that all axial parts of the filter paper drum participate in the filtration of the air, thereby improving the use efficiency of the filter paper drum and ensuring the filtration effect of the filter paper drum.

Description

Technical Field

[0001] The invention relates to the technical field of automobile air filtration, in particular to a filter paper drum structure, a cylindrical air filter element and a filter element manufacturing process. Background Art

[0002] As a key component of the engine's air intake system, the air filter mainly filters impurities through the internal filter element, purifies the air, and provides fresh and clean air for the engine and other air-using components.

[0003] The filter paper cylinder of the cylindrical air filter element is usually made of a single layer of filter paper or a multi-layer composite filter paper, which is repeatedly folded into a wave shape according to a certain width and then surrounded into a cylindrical shape. The filter paper cylinder has several folding surfaces of the same width in the circumferential direction. Since the paper filter paper cylinder is a soft material, it is easy to fold or collapse under the action of negative pressure during use, thereby affecting the filtering effect of the filter paper cylinder. In addition, due to the soft characteristics of the paper filter paper cylinder, the wider the width of the folding surface, the easier it is to deform, fold or collapse. Therefore, the folding surface width of the filter paper cylinder in the prior art is usually narrower, generally only 30-50mm, and the folding surface is used as a filtering surface, and its width is directly related to the dust holding capacity and service life of the filter element. The narrower the width of the folding surface, the smaller the dust holding capacity of the filter element and the shorter the service life. Limited by the folding surface width, the existing air filter element has a small dust holding capacity and a short service life. The air filter element is regularly replaced and maintained for a short period of time, and the maintenance cost is also high. In addition, the airflow in various parts of the existing filter paper cylinder is uneven, and the outer fold spacing and inner fold spacing between the folded surfaces are also uneven, which reduces the use efficiency of the filter paper cylinder and thus affects the filtering effect of the filter paper cylinder. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned existing cylindrical air filter elements, the applicant provides a filter paper cartridge structure with a reasonable structure, a cylindrical air filter element and a filter element manufacturing process. Radial supports and axial supports are arranged in the filter paper cartridge to prevent the filter paper cartridge from folding or collapsing, so that the filter paper cartridge can be provided with a wider folding surface width, thereby increasing the dust holding capacity and life of the filter element, extending the maintenance cycle, reducing the maintenance cost, and ensuring the filtering effect of the filter paper cartridge.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A filter paper cylinder structure is made by repeatedly folding filter paper into a wave shape and then wrapping it into a cylindrical shape. It has a plurality of folded surfaces in the circumferential direction, and there is an outer folding spacing or an inner folding spacing with one side open between adjacent folding surfaces. A plurality of transverse partitions are arranged in the inner folding spacing in the axial direction, and the transverse partitions are radially supported between adjacent folding surfaces.

[0007] As a further improvement of the above technical solution:

[0008] The cross-bars radially fill the cross section corresponding to the inner fold spacing.

[0009] The ends of several transverse partitions of each layer are connected to form an integrated continuous rubber-insulating layer. The distance H between two adjacent rubber-insulating layers is 30-50 mm; the thickness of the rubber-insulating layer is 1-2 mm.

[0010] The width W of the folded surface is 70-100 mm.

[0011] A wire bundle is wound around the outer circumference of the filter paper cylinder, and the winding density of the wire bundle at the lower part of the filter paper cylinder is greater than that at the upper part.

[0012] A cylindrical air filter element adopts the above-mentioned filter paper tube structure, the outer side of the filter paper tube is the air inlet side, and the inner side is the air outlet side. A skeleton assembly is inserted into the air outlet side of the filter paper tube, the upper end of the filter paper tube is provided with an upper end cover, and the lower end is provided with a lower end cover. The through hole in the center of the upper end cover is connected to the air outlet side of the filter paper tube.

[0013] As a further improvement of the above technical solution:

[0014] The upper end of the vertical frame body of the skeleton assembly is provided with a top frame, and the lower end is provided with a bottom frame. A plurality of support columns are vertically arranged between the top frame and the bottom frame, and the plurality of support columns penetrate the filter paper cylinder along the axial direction.

[0015] The top frame includes a plurality of concentric upper circumferential spokes and a plurality of radially arranged upper transverse spokes; the bottom frame includes a plurality of concentric lower circumferential spokes and a plurality of radially arranged lower transverse spokes; bosses are respectively provided at both ends of the support column, and a step surface is provided between the boss and the top surface or the bottom surface of the support column; the support column is inserted at the intersection of the upper circumferential spoke and the upper transverse spoke of the top frame and at the intersection of the lower circumferential spoke and the lower transverse spoke of the bottom frame through the boss.

[0016] A filter element manufacturing process is used for the above-mentioned cylindrical air filter element. The filter paper of the filter element is made into a folding surface and a glue isolation layer by a method of folding and injecting glue at the same time. There is an inner folding spacing at each fold of the filter paper, and glue is then injected into the inner folding spacing; after the filter paper is folded and injected with glue, it is rolled into a cylindrical filter paper tube.

[0017] As a further improvement of the above technical solution:

[0018] After the folded filter paper is rolled into a cylindrical shape along the vertical frame of the skeleton assembly, the support columns of the skeleton assembly are inserted into the top frame and the bottom frame, and the support columns are located within the outer folding spacing of the filter paper; then the upper end cover and the lower end cover are formed by cooling the PU glue; finally, the wire harness is wound around the outer periphery of the filter paper tube; the device for making the filter paper tube includes a paper folding device and a plurality of glue injection devices arranged on one side of the paper folding device and arranged along the height direction of the filter paper, and the plurality of glue injection devices face the air outlet side of the filter paper and are opposite to the first inner folding spacing on the rear side of the paper folding device.

[0019] The beneficial effects of the present invention are as follows:

[0020] (1) The plurality of rubber isolation layers of the present invention divide the filter paper cylinder into a plurality of filter sections. Due to the restriction and guidance of the rubber isolation layers, the air flow is diverted to the plurality of filter sections for filtration, so that all axial parts of the filter paper cylinder participate in the filtration of the air, thereby improving the use efficiency of the filter paper cylinder and ensuring the filtration effect of the filter paper cylinder. The plurality of transverse diaphragms within the inner folding spacing act as radial supporting structures to radially support the folding surface. On the one hand, the radial strength of the folding surface is improved, the folding surface is prevented from being folded or collapsed under the action of negative pressure, and the filtering efficiency is ensured. Moreover, due to the radial supporting positioning of the transverse diaphragms, the folding surface is not easy to deform, fold or collapse even if it has a very wide width, so that the folding surface of the filter paper tube can be set as wide as possible in a limited space. Compared with the prior art, the folding surface of the present invention is expanded by more than double, which greatly improves the dust holding capacity of the filter paper tube, improves the service life, extends the replacement and maintenance cycle of the filter element, and reduces the maintenance cost. On the other hand, due to the supporting and positioning effect of the transverse diaphragms on the folding surface, the outer folding spacing and the inner folding spacing of the filter paper tube are also relatively fixed, and the outer folding spacing and the inner folding spacing between each folding surface are more uniform, so that the air flow flows through each outer folding spacing and the inner folding spacing more uniformly, improving the use efficiency of each folding surface, thereby improving the filtering efficiency of the filter paper tube, and because the transverse diaphragms support and shape each folding surface, the filter paper tube as a whole is more stretched and more beautiful.

[0021] (2) The plurality of support columns of the present invention serve as an axial support structure to provide radial axial support to the folding surface. On the one hand, the axial strength of the folding surface is improved, and the folding surface is further prevented from folding or collapsing under the action of negative pressure, thereby ensuring the filtration efficiency and improving the axial stiffness of the filter paper tube. On the other hand, the support strength of the entire skeleton assembly is increased, making the skeleton assembly as a whole more stable and reliable.

[0022] (3) The wire bundle wound around the lower part of the filter paper tube of the present invention is denser and the wire bundle wound around the upper part is sparser. When the user is maintaining and replacing the filter element, the user can hold the lower part with a denser wire bundle. At this time, the wire bundle can isolate and protect the filter paper, avoiding direct contact between the hand and the filter paper.

[0023] (4) The filter folds and the rubber barrier layer of the filter paper tube of the present invention are formed by injecting glue as they are folded. The inner fold spacing between the folded surfaces is fixed by injection glue once it is folded. The folded surface is supported and fixed in position by the rubber barrier layer, which is more conducive to preventing the folded surface, the outer fold spacing and the inner fold spacing from being deformed or changing in spacing during the continuous folding process of the filter paper and the subsequent winding process, thereby ensuring that the spacing between each filter fold meets the set value requirement, and further ensuring that the horizontal length of the filter paper after folding meets the set value requirement, thereby preventing the filter paper tube from exceeding the size tolerance and affecting the subsequent filter element production; and the glue injection device continuously injects glue, thereby ensuring the continuity and thickness of the rubber barrier layer and preventing the rubber barrier layer from being broken and affecting its sealing, splitting and supporting properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is the front view of the present invention.

[0025] Figure 2 for Figure 1 Cross-sectional view of section AA.

[0026] Figure 3 It is a three-dimensional cutaway view of the present invention.

[0027] Figure 4 This is a cross-sectional view of the filter paper tube.

[0028] Figure 5 for Figure 4 Enlarged view of part B in the middle.

[0029] Figure 6 It is a three-dimensional diagram of the rubber insulation layer.

[0030] Figure 7 for Figure 6 Enlarged view of part C in the middle.

[0031] Figure 8 A three-dimensional diagram of a skeleton.

[0032] Fig. 9 A three-dimensional diagram of the support rod.

[0033] Fig.10 Schematic diagram of the production of filter paper tube.

[0034] In the figure: 1, filter paper cylinder; 11, folding surface; 12, outer fold spacing; 13, inner fold spacing; 14, rubber layer; 141, horizontal partition; 15, wire harness; 10, air inlet side; 20, air outlet side;

[0035] 2. Frame assembly; 21. Vertical frame; 22. Top frame; 221. Upper circumferential spoke; 222. Upper transverse spoke; 23. Bottom frame; 231. Lower circumferential spoke; 232. Lower transverse spoke; 24. Support column; 241. Upper boss; 242. Upper step surface; 243. Lower boss; 244. Lower step surface;

[0036] 3. Upper end cover; 31. Through hole; 4. Lower end cover;

[0037] 5. Paper folding device; 6. Glue injection device. DETAILED DESCRIPTION

[0038] The specific implementation of the present invention is described below in conjunction with the accompanying drawings.

[0039] like Figures 1 to 3As shown, the air filter element described in the present invention includes a cylindrical filter paper tube 1, the outer side of the filter paper tube 1 is an air inlet side 10, and the inner side is an air outlet side 20, a skeleton assembly 2 is inserted into the air outlet side 20 of the filter paper tube 1, an upper end cover 3 is bonded and fixed to the upper end of the filter paper tube 1, and a lower end cover 4 is bonded and fixed to the lower end, a through hole 31 is opened in the center of the upper end cover 3, the through hole 31 is connected to the air outlet side 20 of the filter paper tube 1, and the lower end cover 4 covers the bottom surface of the filter paper tube 1.

[0040] like Figure 4 , Figure 5 As shown, the filter paper tube 1 is made of filter paper that is repeatedly folded into a wave shape according to a certain width and then wrapped into a cylindrical shape. After folding and forming, the filter paper tube 1 has a plurality of folding surfaces 11 with the same width and connected in series in the circumferential direction. There is a folding distance with one side open between adjacent folding surfaces 11. The folding distance with the open side located at the air inlet side 10 is the outer folding distance 12, and the folding distance with the opening located at the air outlet side 20 is the inner folding distance 13. In the filter paper tube 1, a plurality of layers of rubber insulation layers 14 with spacing are sequentially arranged axially from top to bottom. The spacing H between two adjacent layers of rubber insulation layers 14 is 30-50mm, preferably 40mm. The rubber insulation layers 14 are filled in the inner folding distance 13 radially. The plurality of rubber insulation layers 14 divide the filter paper tube 1 into a plurality of filter intervals. Due to the restriction and guiding effect of the rubber insulation layers 14, the air flow is diverted to a plurality of filter intervals for filtration, so that all axial parts of the filter paper tube 1 participate in the filtration of the air, thereby improving the use efficiency of the filter paper tube 1 and ensuring the filtration effect of the filter paper tube 1. As shown Figure 6 , Figure 7 As shown, in this embodiment, the rubber isolation layer 14 is an integrated continuous sawtooth annular thin rubber layer, and has a plurality of radially divergent transverse ribs 141 corresponding to the inner folding spacing 13 in the circumferential direction, and the transverse ribs 141 match the cross section of the inner folding spacing 13; of course, in other embodiments, the rubber isolation layer 14 may also be discontinuous, but composed of separate transverse ribs 141, that is, the ends of the transverse ribs 141 are not connected. Figure 4 , Figure 5As shown, the cross-bars 141 radially fill the corresponding cross section of the inner folding spacing 13 and are supported between adjacent folding surfaces 11, that is, the plurality of cross-bars 141 within the inner folding spacing 13 act as radial support structures to radially support the folding surfaces 11. On the one hand, the radial strength of the folding surfaces 11 is improved to prevent the folding surfaces 11 from folding or collapsing under the action of negative pressure, thereby ensuring the filtration efficiency. Moreover, due to the radial support and positioning of the cross-bars 141, the folding surfaces 11 are not easily deformed, folded or collapsed even if they have a very wide width, so that the folding surfaces 11 of the filter paper tube 1 can be set as wide as possible within a limited space. The width W of the folding surface 11 of the present invention can be set to 70-100 mm, preferably 80 mm, compared with the prior art, the width of the folding surface 11 is expanded by more than double, which greatly improves the dust holding capacity of the filter paper tube 1, increases the service life, extends the replacement and maintenance cycle of the filter element, and reduces the maintenance cost; on the other hand, due to the supporting and positioning effect of the cross-bar 141 on the folding surface 11, the outer folding spacing 12 and the inner folding spacing 13 of the filter paper tube 1 are also relatively fixed, and the outer folding spacing 12 and the inner folding spacing 13 between each folding surface 11 are more uniform, so that the air flow flows more evenly through each outer folding spacing 12 and the inner folding spacing 13, thereby improving the use efficiency of each folding surface 11, thereby improving the filtration efficiency of the filter paper tube 1, and because the cross-bar 141 expands and shapes each folding surface 11, the filter paper tube 1 as a whole is more stretched and more beautiful.

[0041] like Figure 3 , Figure 4 As shown, the outer circumferential surface of the filter paper tube 1 is wound with a wire bundle 15, which is used to fix the filter paper tube 1 as a whole and increase the stability of the filter paper tube 1 as a whole; the winding density of the wire bundle 15 at the lower part of the filter paper tube 1 is greater than the winding density at the upper part, that is, the wire bundle 15 wound at the lower part of the filter paper tube 1 is denser, and the upper part is sparser. When maintaining and replacing the filter element, the user can hold the lower part of the wire bundle 15 with a denser density. At this time, the wire bundle 15 can play a role in isolating and protecting the filter paper to avoid direct contact between the hands and the filter paper.

[0042] like Figure 8 As shown, the skeleton assembly 2 includes a vertical frame body 21 parallel to the axial direction of the filter paper cartridge 1, a top frame 22 radially arranged at the upper end, and a bottom frame 23 radially arranged at the lower end. A plurality of support columns 24 are vertically arranged between the top frame 22 and the bottom frame 23, and the plurality of support columns 24 are evenly arranged along the circumferential direction. After installation, the filter paper cartridge 1 is sleeved on the outer periphery of the vertical frame body 21 and located between the top frame 22 and the bottom frame 23. The plurality of support columns 24 penetrate the filter paper cartridge 1 along the axial direction, as shown in FIG. Figure 2As shown, the support columns 24 are inserted into the outer folding spacing 12 of the filter paper tube 1. A plurality of support columns 24 serve as an axial support structure to provide radial axial support to the folding surface 11. On the one hand, the axial strength of the folding surface 11 is improved, and the folding surface 11 is further prevented from folding or collapsing under the action of negative pressure, thereby ensuring the filtration efficiency and improving the axial stiffness of the filter paper tube 1. On the other hand, the support strength of the skeleton assembly 2 as a whole is increased, making the skeleton assembly 2 as a whole more stable and reliable. The top frame 22 includes a plurality of concentric upper circumferential spokes 221 and a plurality of radially arranged upper transverse spokes 222; the bottom frame 23 includes a plurality of concentric lower circumferential spokes 231 and a plurality of radially arranged lower transverse spokes 232. The lower circumferential spokes 231 correspond to the upper circumferential spokes 221, and the lower transverse spokes 232 correspond to the upper transverse spokes 222. As shown in FIG. Fig. 9 As shown, the upper end of the support column 24 is provided with an upper boss 241, and an upper step surface 242 is provided between the upper boss 241 and the top surface of the support column 24; the lower end of the support column 24 is provided with a lower boss 243, and a lower step surface 244 is provided between the lower boss 243 and the bottom surface of the support column 24. Figure 8 As shown, the upper boss 241 of the support column 24 is inserted into the mounting hole at the intersection of the upper circumferential spoke 221 and the upper transverse spoke 222 of the top frame 22, and the lower boss 243 of the support column 24 is inserted into the mounting hole at the intersection of the lower circumferential spoke 231 and the lower transverse spoke 232 of the bottom frame 23. The upper step surface 242 and the lower step surface 244 can limit the support column 24; the support column 24 is plugged into and matched with the top frame 22 and the bottom frame 23 through the upper boss 241 and the lower boss 243, which is easy to disassemble and assemble.

[0043] like Fig.10 As shown, the manufacturing device of the filter paper tube 1 includes a paper folding device 5 and a plurality of glue injection devices 6 arranged on one side of the paper folding device 5 and arranged along the height direction of the filter paper (i.e., the axial direction of the filter paper tube 1), the plurality of glue injection devices 6 face the air outlet side 20 of the filter paper and are directly opposite to the first inner folding spacing 13 on the rear side of the paper folding device 5 (in the figure, the paper folding device 5 and the glue injection device 6 are both simply schematically shown), and after the filter paper is folded out of the inner folding spacing 13 by the paper folding device 5, glue is injected into the inner folding spacing 13 by the glue injection device 6.

[0044] The specific manufacturing process of the filter paper tube 1 and the filter element includes the following steps:

[0045] (1) First, a flat filter paper is folded by a paper folding device 5 and a folded surface 11 is squeezed out;

[0046] (2) Every time the filter paper is folded to form an inner folding interval 13, the glue injection device 6 immediately injects glue into the inner folding interval 13, that is, the filter paper is injected with glue as it is folded, and the glue is injected as soon as the inner folding interval 13 is folded. The filter paper is continuously folded to form an inner folding interval 13, and the glue injection device 6 continuously injects glue into the inner folding interval 13. After the glue liquid solidifies, a continuous glue barrier layer 14 is formed; the filter fold and the glue barrier layer 14 are formed by the glue injection method as they are folded. Once the inner folding interval 13 between the folding surfaces 11 is folded, the glue is injected and fixed. The folding surface 11 is supported and fixed by the glue barrier layer 14, which is more conducive to preventing the folding surface 11 and the outer The fold spacing 12 and the inner fold spacing 13 are deformed or the spacing changes during the continuous folding process of the filter paper and the subsequent winding process, ensuring that the spacing between each filter fold meets the set value requirement, thereby ensuring that the horizontal length of the filter paper after folding meets the set value requirement, preventing the filter paper cylinder 1 from exceeding the size tolerance and affecting the subsequent production of the filter element; and the glue injection device 6 continuously injects glue, ensuring the continuity and thickness of the glue layer 14, preventing the glue layer 14 from breaking and affecting its sealing splitting and supporting properties. The thickness of the glue layer 14 is 1-2mm, preferably 1.5mm;

[0047] (3) After the filter paper is folded and glued, the filter paper is rolled into a cylindrical shape along the vertical frame 21 of the skeleton assembly 2, and the corresponding folded surfaces 11 at both ends are glued and fixed with the middle seam glue to form a filter paper tube 1;

[0048] (4) Then, the support column 24 of the skeleton assembly 2 is inserted into the top frame 22 and the bottom frame 23. The upper boss 241 and the lower boss 243 of the support column 24 cooperate with the mounting holes of the top frame 22 and the bottom frame 23 to achieve positioning. The support column 24 is located within the outer folding spacing 12 of the filter paper to ensure a beautiful appearance.

[0049] (5) Then, the assembled filter paper tube 1 and the frame assembly 2 are placed in a foaming mold, and the PU glue in the foaming mold is cooled and formed to form the upper end cover 3 and the lower end cover 4 structure of the filter element;

[0050] (6) Finally, a wire harness 15 is wound around the outer circumference of the filter paper tube 1 to fix the filter paper tube 1 into shape, thereby completing the production of the filter element.

[0051] The above description is an explanation of the present invention, not a limitation of the present invention. The present invention may be modified in any form without violating the spirit of the present invention.

Claims

1. A cylindrical air filter element, characterized in that: A filter paper cylinder structure is adopted, wherein the filter paper cylinder structure is formed by repeatedly folding filter paper into a wave shape and then forming a cylindrical shape, and has a plurality of folding surfaces (11) in the circumferential direction, and an outer folding spacing (12) or an inner folding spacing (13) with one side open is provided between adjacent folding surfaces (11), and a plurality of transverse partitions (141) are provided in the inner folding spacing (13) in the axial direction, and the transverse partitions (141) are radially supported between adjacent folding surfaces (11); the transverse partitions (141) radially fill the corresponding cross section of the inner folding spacing (13); the outer side of the filter paper cylinder (1) is an air inlet side (10), and the inner side is an air outlet side (20); a skeleton assembly (2) is inserted into the air outlet side (20) of the filter paper cylinder (1), an upper end cover (3) is provided at the upper end of the filter paper cylinder (1), and a lower end cover (4) is provided at the lower end; a through hole (31) in the center of the upper end cover (3) is connected to the air outlet side (20) of the filter paper cylinder (1); The vertical frame body (21) of the frame assembly (2) is provided with a top frame (22) at the upper end and a bottom frame (23) at the lower end; a plurality of support columns (24) are vertically arranged between the top frame (22) and the bottom frame (23); the plurality of support columns (24) pass through the filter paper cylinder (1) along the axial direction; the top frame (22) includes a plurality of concentric upper circumferential spokes (221) and a plurality of radially arranged upper transverse spokes (222); the bottom frame (23) includes a plurality of concentric lower circumferential spokes (221) and a plurality of radially arranged upper transverse spokes (222); The support column (24) comprises a circumferential spoke (231) and a plurality of radially arranged lower transverse spokes (232); bosses are respectively provided at both ends of the support column (24), and a step surface is provided between the bosses and the top surface or the bottom surface of the support column (24); the support column (24) is inserted into the intersection of the upper circumferential spoke (221) and the upper transverse spoke (222) of the top frame (22) and the intersection of the lower circumferential spoke (231) and the lower transverse spoke (232) of the bottom frame (23) through the bosses.

2. The cylindrical air filter element according to claim 1, characterized in that: The ends of a plurality of transverse partitions (141) of each layer are connected to form an integral and continuous rubber-insulating layer (14); the distance H between two adjacent rubber-insulating layers (14) is 30-50 mm; and the thickness of the rubber-insulating layer (14) is 1-2 mm.

3. The cylindrical air filter element according to claim 1, characterized in that: The width W of the folding surface (11) is 70-100 mm.

4. The cylindrical air filter element according to claim 1, characterized in that: A wire bundle (15) is wound around the outer circumferential surface of the filter paper cylinder (1), and the winding density of the wire bundle (15) at the lower part of the filter paper cylinder (1) is greater than the winding density at the upper part.

5. A filter element manufacturing process, characterized in that: Used to manufacture the cylindrical air filter element as claimed in claim 1, the filter paper of the filter element is manufactured by adopting a method of simultaneously folding and injecting glue to manufacture the folding surface (11) and the glue isolation layer (14), and each time the filter paper is folded to form an inner folding space (13), glue is injected into the inner folding space (13); after the filter paper is folded and injected with glue, it is rolled into a cylindrical filter paper tube (1).

6. The filter element manufacturing process according to claim 5, characterized in that: After the folded filter paper is rolled into a cylindrical shape along the vertical frame body (21) of the skeleton assembly (2), the support column (24) of the skeleton assembly (2) is plugged into the top frame (22) and the bottom frame (23), and the support column (24) is located within the outer folding spacing (12) of the filter paper; then, the upper end cover (3) and the lower end cover (4) are formed by cooling with PU glue; finally, a harness (15) is wound around the outer periphery of the filter paper cylinder (1); the device for manufacturing the filter paper cylinder (1) comprises a paper folding device (5) and a plurality of glue injection devices (6) arranged on one side of the paper folding device (5) and arranged along the height direction of the filter paper, and the plurality of glue injection devices (6) face the air outlet side (20) of the filter paper and are directly opposite to the first inner folding spacing (13) on the rear side of the paper folding device (5).

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