Motor

Abstract

The utility model relates to a motor, which solves the problem in the prior art that a sealing ring between a shell seat and a motor cover on the motor is easy to deviate when the motor is assembled and works, and adopts the technical scheme that the motor comprises a shell, a motor cover, the shell seat arranged between the shell and the motor cover, and the sealing ring arranged between the shell seat and the motor cover, the sealing structure is characterized in that a positioning structure is arranged on the sealing ring, a positioning matching structure is arranged on the shell seat, and the positioning structure is correspondingly matched with the positioning matching structure so that the sealing ring can be stably limited between the shell seat and the machine cover. The sealing structure has the advantages that the positioning structure is arranged on the sealing ring, the positioning matching structure is arranged on the shell base, and the sealing ring is stably limited between the shell base and the machine cover through mutual matching of the positioning structure and the positioning matching structure, so that not only is the assembly efficiency improved, but also the assembly quality is improved; when the motor works, the shape and the fixing position of the sealing ring are stable, so that the working reliability of the motor is improved, and the fault occurrence rate is reduced.

Description

Technical Field

[0001] The utility model relates to the field of motors, in particular to a motor with an improved sealing pad structure. Background Art

[0002] Conventional motors include a housing, a cover, a housing seat disposed between the housing and the cover, and a sealing ring disposed between the housing seat and the cover. The sealing ring is typically flexible, thin, and relatively large in diameter. Because oil- and water-filled motors are susceptible to internal pressure differentials during operation, or due to the operating environment, these pressure differentials can easily cause the sealing ring to deform or shift, leading to seal failure and damage to the motor.

[0003] In order to reduce the deviation and misalignment of the sealing ring during assembly or use, and to ensure that the sealing ring can be stably and accurately limited between the shell seat and the machine cover, a backing adhesive layer is provided on one side of the sealing ring during assembly, and the sealing ring is fixed to the shell seat through the backing adhesive layer. However, the assembler is likely to come into contact with the glue during assembly, and some of the glue is likely to stick to the assembler's hands. When the assembler installs the sealing gasket with glue on his hands, the sealing ring is likely to stick to his hands, making it difficult to smoothly fix the sealing ring to the shell seat, or the glue is spread to the non-fixed surface of the sealing gasket (such as the side). The glue on the non-fixed surface is likely to stick to impurities and affect the sealing between the shell seat and the machine cover. In addition, the adhesive force of the backing adhesive layer is difficult to resist the pressure difference, and there is still the problem of the sealing ring being easily deformed or displaced. Summary of the Invention

[0004] The purpose of the present utility model is to solve the above-mentioned problems existing in the prior art and to provide a motor, wherein a positioning structure is provided on the sealing ring and a positioning and matching structure is provided on the shell seat. The positioning structure and the positioning and matching structure cooperate with each other to stably limit the sealing ring between the shell seat and the machine cover, which is not only conducive to improving the assembly efficiency but also to improving the assembly quality during the motor assembly; when the motor is working, the shape and fixed position of the sealing ring are stable, which is conducive to improving the working reliability of the motor and reducing the occurrence rate of failures.

[0005] The above technical purpose of the present invention is mainly solved by the following technical solutions: a motor, comprising a casing, a cover, a casing seat arranged between the casing and the cover, and a sealing ring arranged between the casing seat and the cover, characterized in that a positioning structure is provided on the sealing ring, a positioning matching structure is provided on the casing seat, and the positioning structure corresponds to the positioning matching structure and is used to stably limit the sealing ring between the casing seat and the cover. This technical solution provides a positioning structure on the sealing ring and a positioning matching structure on the casing seat. The positioning structure and the positioning matching structure cooperate with each other to stably limit the sealing ring between the casing seat and the cover, which is not only conducive to improving assembly efficiency and assembly quality, but also makes it difficult for the sealing ring to deform or shift when there is a pressure difference between the inside and outside of the motor, thereby improving the working reliability of the motor and reducing the occurrence of failures.

[0006] As a further improvement and supplement to the above technical solution, the present invention employs the following technical measures: the sealing ring includes a sealing body, and the positioning structure and the sealing body are integrally formed. This improves the production efficiency of the sealing ring and avoids the installation efficiency and precision issues that arise with the use of parts, thereby ensuring the sealing performance of the sealing ring when used in motors.

[0007] Preferably, a plurality of extension ears are provided on the inner or outer edge of the sealing body, and a first connecting hole is provided on the extension ear. The first connecting hole is provided corresponding to the second connecting hole of the shell base and the third connecting hole on the machine cover, so that the connecting member passes through the second connecting hole, the first connecting hole and the third connecting hole in sequence to fix the machine cover, the sealing ring and the shell base. The extension ear is provided to fit the end face of the connecting column on the shell base, and the first connecting hole is provided so that the second connecting hole of the shell base is coaxially arranged with the first connecting hole, and the aperture size matches, so that the connecting member is conveniently inserted into the corresponding connecting hole to assemble the machine cover to the shell base. The connecting member also fixes the position of the extension ear, that is, the connecting ear fixes the sealing ring, which is conducive to ensuring that the sealing ring is stable in position and does not shift or deform during the operation of the motor, thereby ensuring the sealing reliability of the sealing ring.

[0008] Preferably, the positioning structure includes a positioning bead provided on the extension ear, the positioning bead being located at one end of the first connection hole facing the housing seat and protruding axially. The positioning and matching structure includes a chamfered corner at the opening of the second connection hole. The positioning bead is embedded in the second connection hole and fits the chamfered corner. The inner diameter of the positioning bead matches the inner diameter of the second connection hole. The positioning bead and the chamfered corner at the opening of the second connection hole form a nested fit, which facilitates the positioning and fixing of the sealing ring, facilitates assembly, and helps prevent displacement during motor operation.

[0009] Preferably, the positioning structure includes an outer flange and / or an inner flange, and the outer flange and the inner flange are respectively arranged on the outer edge and the inner edge of the sealing body, and the positioning matching structure includes an outer step groove and / or an inner step groove provided on the shell seat, and the outer flange and the inner flange are respectively snap-fitted with the corresponding outer step groove and the inner step groove. The provision of the outer flange and / or the inner flange increases the positioning position between the sealing ring and the shell seat, which is further conducive to fixing the sealing ring, not only helping to improve the assembly efficiency of the sealing ring, but also helping to improve the assembly quality of the sealing ring, and further preventing the possibility of displacement and deformation of the sealing ring during the operation of the motor, thereby ensuring the sealing reliability of the sealing ring. At the same time, the nested fit between the positioning convex ring and the chamfer at the opening of the second connecting hole can effectively resist radially inward and radially outward forces, further helping to improve assembly reliability and assembly efficiency, and preventing the sealing ring from shifting and deforming during the use of the motor.

[0010] Preferably, the positioning structure includes an outer flange provided on the outer edge of the sealing body and a plurality of elastic clips provided at intervals on the inner edge of the sealing body. The positioning and matching structure includes an outer step groove provided on the shell seat and a first inner hole wall of the shell seat. The outer flange and the outer step groove are snap-fitted together, and the elastic clips are snap-fitted together with the first inner hole wall. This technical solution is a parallel technical solution to the previous technical solution. The sealing ring is positioned radially inward and radially outward by matching the outer flange and the outer step groove, and the elastic clips and the first inner hole wall of the shell seat, effectively ensuring efficient and high-quality assembly of the sealing ring. At the same time, it effectively ensures that the sealing ring will not shift or deform during the operation of the motor, thereby ensuring the sealing reliability of the sealing ring.

[0011] Preferably, the elastic buckle includes a buckle seat provided on the second inner hole wall of the sealing body and radially protruding, and an elastic buckle head provided on the buckle seat, the elastic buckle head radially protruding from the second inner hole wall of the sealing body, the buckle head having a hook-shaped cross section, the buckle head being curved toward the outer edge of the sealing body, and an elastic clamping groove provided between the elastic buckle head and the buckle seat, the elastic clamping groove being provided away from the outer edge of the sealing body. This is conducive to ensuring that the elastic buckle exerts a certain clamping force on the first inner hole wall, so that the sealing ring can be stably and reliably fixed to the shell seat.

[0012] In order to ensure efficient and high-quality assembly of the sealing ring and ensure the stability (no deformation, no displacement) and sealing reliability of the sealing ring during the operation of the motor, the size of each part of the sealing ring is also limited:

[0013] Preferably, the radial width B of the sealing body is: B = (D0-d) / 2, the thickness of the sealing body is B < (D0-d) / 5, and the height h of the outer flange and the height of the inner flange of the positioning structure are: h > 0.8B, wherein D0 is the outer diameter of the sealing body, and d is the inner diameter of the sealing body.

[0014] One end of the shell seat that cooperates with the machine cover is a narrow end, and the end size of the narrow end is: (D1-D2) / D1<0.1, D1 is the outer diameter of the end of the narrow end, and D2 is the inner diameter of the end of the narrow end.

[0015] Preferably, the height of the positioning protrusion above the corresponding surface of the extension ear is less than the thickness of the extension ear; the circumscribed circle diameter of the inner wall of the elastic buckle on the sealing body is equal to D1, and the inscribed circle diameter of the first inner hole wall of the shell seat and the inscribed circle diameter of the extension ear are both equal to D2; when the extension ear is provided on the outer edge of the shell seat, D1<D2; when the extension ear is provided on the inner edge of the shell seat, D1>D2.

[0016] The beneficial effects of the present invention are as follows: 1. A positioning structure is provided on the sealing ring, and a positioning and matching structure is provided on the shell seat. The positioning structure and the positioning and matching structure cooperate with each other, so that the sealing ring is stably limited between the shell seat and the machine cover, which is not only beneficial to improving the assembly efficiency and the assembly quality, but also, when there is a pressure difference between the inside and outside of the motor, the sealing ring is not easily deformed or shifted, thereby improving the working reliability of the motor and reducing the occurrence rate of failures. 2. The positioning structure and the positioning and matching structure have a variety of positioning and fixing methods, so that during assembly, the sealing ring can be efficiently fixed to the corresponding part of the shell seat; during the operation of the motor, the sealing ring does not shift or deform, ensuring the sealing effect, thereby improving the working stability and reliability of the motor. 3. In order to enable the sealing ring to be assembled efficiently and with high quality, and to ensure the stability (no deformation, no shifting) and sealing reliability of the sealing ring during the operation of the motor: the size of each part of the sealing ring is also limited. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a partial structural schematic diagram of a cross-section of the present invention.

[0018] Figure 2 This is a structural diagram of the shell seat involved in the utility model.

[0019] Figure 3 This is a structural diagram of the sealing ring involved in Examples 1-3 of the present utility model.

[0020] Figure 4 yes Figure 3 A schematic diagram of a front view structure.

[0021] Figure 5 yes Figure 4 Schematic diagram of the AA-direction structure.

[0022] Figure 6 yes Figure 5 Schematic diagram of the enlarged structure of part B in the middle.

[0023] Figure 7 This is a structural diagram of the sealing ring involved in Example 4 of the present utility model.

[0024] Figure 8 yes Figure 7 A schematic diagram of a front view structure.

[0025] Figure 9 yes Figure 8 Schematic diagram of the middle BB structure.

[0026] Figure 10 yes Figure 9 Schematic diagram of the enlarged structure of part D in the middle.

[0027] Figure 11 This is a schematic diagram of an assembly structure of the shell seat involved in the utility model and the sealing ring involved in Example 2.

[0028] Figure 12 yes Figure 11 Schematic diagram of the explosion structure.

[0029] In the figure: 1. casing; 2. casing base; 3. machine cover; 4. sealing ring; 5. extension ear; 6. first connecting hole; 7. second connecting hole; 8. third connecting hole; 9. positioning convex ring; 10. outer flange; 11. outer step groove; 12. elastic buckle; 13. first inner hole wall; 14. buckle seat; 15. elastic buckle head; 16. second inner hole wall; 17. elastic clamping groove; 18. connecting piece; 19. chamfer; 20. sealing body. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be further specifically described below with reference to embodiments and in conjunction with the accompanying drawings.

[0031] Example 1: Figure 1-6 As shown, a motor includes a casing 1, a cover 3, a casing base 2 arranged between the casing 1 and the cover 3, and a sealing ring 4 arranged between the casing base 2 and the cover 3.

[0032] The difference between this technical solution and the prior art is that:

[0033] The sealing ring 4 is provided with a positioning structure, and the shell base 2 is provided with a positioning matching structure. The positioning structure corresponds to the positioning matching structure to ensure that the sealing ring 4 is stably limited between the shell base 2 and the machine cover 3.

[0034] In the present technical solution, a positioning structure is provided on the sealing ring 4 and a positioning matching structure is provided on the shell seat 2. The positioning structure and the positioning matching structure cooperate with each other to stably limit the sealing ring 4 between the shell seat 2 and the machine cover 3. This is not only beneficial to improving the assembly efficiency, but also to improving the assembly quality. When there is a pressure difference between the inside and outside of the motor, the sealing ring 4 is not prone to deformation or displacement, which is beneficial to improving the working reliability of the motor and reducing the occurrence rate of failures.

[0035] In actual applications, in order to facilitate production and processing, and to avoid assembly (excluding the case where the sealing ring 4 is formed by assembling multiple parts), the sealing ring 4 includes a sealing body 20, and the positioning structure and the sealing body 20 are an integrated structure, which is beneficial to improving the production efficiency of the sealing ring 4, avoiding the installation efficiency and installation accuracy problems caused by the need to install parts, and thus helping to ensure the sealing performance of the sealing ring 4 when used in the motor.

[0036] In order to enable efficient and high-quality assembly of the sealing ring 4 and ensure the stability (no deformation, no displacement) and sealing reliability of the sealing ring 4 during the operation of the motor, the sizes of various parts of the sealing ring 4 are also limited:

[0037] In actual application, the radial width B of the sealing body 20 is: B = (D0-d) / 2, the thickness B of the sealing body 20 is < (D0-d) / 5, and the height h of the outer flange 10 and the height of the inner flange of the positioning structure are: h>0.8B, wherein D0 is the outer diameter of the sealing body 20, and d is the inner diameter of the sealing body 20.

[0038] In actual application, the end of the shell base 2 that cooperates with the machine cover 3 is the narrow end, and the end size of the narrow end is: (D1-D2) / D1<0.1, D1 is the outer diameter of the end of the narrow end, and D2 is the inner diameter of the end of the narrow end.

[0039] In actual application, the height of the positioning protrusion 9 protruding from the corresponding surface of the extension ear 5 is less than the thickness of the extension ear 5; the circumscribed circle diameter of the inner wall of the elastic buckle 15 on the sealing body 20 is equal to D1, and the inscribed circle diameter of the first inner hole wall 13 of the shell seat 2 and the inscribed circle diameter of the extension ear 5 are both equal to D2; when the extension ear 5 is provided on the outer edge of the shell seat 2, D1<D2; when the extension ear 5 is provided on the inner edge of the shell seat 2, D1>D2.

[0040] In practical applications, for example, when D1 takes a value of 130 mm and D2 takes a value of 120 mm, D0 and d are equal to D1 and D2 respectively, that is, D0 = 130 mm, d = 120 mm. At this time, the width of the sealing body 20 is 5 mm, the thickness B of the sealing body 20 is less than 2 mm (such as 1.5 mm), the height h of the outer flange 10 is greater than 1.2 mm (such as 1.5 mm), and the thickness b of the outer flange 10 is 1.2 mm.

[0041] Example 2: Figure 1-6 As shown, based on Example 1, a plurality of extension ears 5 are provided on the inner or outer edge of the sealing body 20. Each extension ear 5 is provided with a first connection hole 6. The first connection hole 6 corresponds to the second connection hole 7 of the housing base 2 and the third connection hole 8 on the cover 3. A connector 18 is sequentially passed through the second connection hole 7, the first connection hole 6, and the third connection hole 8 to secure the cover 3, the sealing ring 4, and the housing base 2. The extension ear 5 is provided to fit against the end surface of the connecting post on the housing base 2. The first connection hole 6 is provided so that the second connection hole 7 and the first connection hole 6 of the housing base 2 are coaxially arranged, with matching apertures. This facilitates insertion of the connector 18 into the corresponding connection hole to assemble the cover 3 to the housing base 2. The connector 18 also secures the position of the extension ear 5, i.e., the extension ear secures the sealing ring 4. This helps ensure that the sealing ring 4 remains stable and does not shift or deform during motor operation, thereby ensuring the sealing reliability of the sealing ring 4.

[0042] In this embodiment, preferably, a plurality of extension ears 5 are provided on the inner edge of the sealing body 20 .

[0043] In this embodiment, to further improve the positioning effect, facilitate assembly, increase assembly efficiency, and further help prevent the seal ring 4 from shifting or deforming during motor operation, the positioning structure includes a positioning bead 9 provided on the extension ear 5. The positioning bead 9 is located at the end of the first connecting hole 6 facing the housing seat 2 and protrudes axially. The positioning matching structure includes a chamfer 19 at the opening of the second connecting hole 7. The positioning bead 9 is embedded in the second connecting hole 7 and fits the chamfer 19. The inner diameter of the positioning bead 9 is adapted to the inner diameter of the second connecting hole 7. The positioning bead 9 and the chamfer 19 at the opening of the second connecting hole 7 form a nested fit, which facilitates the positioning and fixing of the seal ring 4, facilitates assembly, and helps prevent shifting during motor operation.

[0044] Example 3: Based on Example 1, the positioning structure includes an outer flange 10 and / or an inner flange, and the outer flange 10 and the inner flange are respectively arranged on the outer edge and the inner edge of the sealing body 20, and the positioning matching structure includes an outer step groove 11 and / or an inner step groove arranged on the shell seat 2, and the outer flange 10 and the inner flange are respectively snap-fitted with the corresponding outer step groove 11 and the inner step groove.

[0045] The provision of the outer flange 10 and / or the inner flange increases the positioning area between the sealing ring 4 and the housing 2, further facilitating the fixing of the sealing ring 4, thereby not only improving the assembly efficiency and quality of the sealing ring 4, but also further preventing the possibility of displacement and deformation of the sealing ring 4 during motor operation, thereby ensuring the sealing reliability of the sealing ring 4. At the same time, the nested fit between the positioning bead 9 and the chamfer 19 at the opening of the second connecting hole 7 can effectively resist radially inward and radially outward forces, further improving assembly reliability and efficiency, and preventing the displacement and deformation of the sealing ring 4 during motor use.

[0046] In this embodiment, preferably, the positioning structure includes an outer flange 10, which is arranged on the outer edge of the sealing body 20, and the positioning matching structure includes an outer step groove 11 arranged on the shell seat 2, and the outer flange 10 is snap-fitted with the outer step groove 11 and the inner step groove.

[0047] Example 4: Figure 7-12 As shown, the positioning structure includes an outer flange 10 arranged on the outer edge of the sealing body 20 and a plurality of elastic clips 12 arranged at intervals on the inner edge of the sealing body 20. The positioning matching structure includes an outer step groove 11 arranged on the shell seat 2 and a first inner hole wall 13 of the shell seat 2. The outer flange 10 is snap-fitted with the outer step groove 11, and the elastic clip 12 is snap-fitted with the first inner hole wall 13.

[0048] This technical solution is a parallel technical solution to the previous technical solution. The sealing ring 4 cooperates with the outer flange 10 and the outer step groove 11, and the elastic buckle 12 cooperates with the first inner hole wall 13 of the shell seat 2 to form radially inward and radially outward positioning, effectively ensuring efficient and high-quality assembly of the sealing ring 4, and at the same time effectively ensuring that the sealing ring 4 will not shift or deform during the operation of the motor, thereby ensuring the sealing reliability of the sealing ring 4.

[0049] In actual application, in order to ensure that the elastic buckle 12 limits the sealing ring 4, the elastic buckle 12 includes a buckle seat 14 provided on the second inner hole wall 16 of the sealing body 20 and radially protruding, and an elastic buckle head 15 provided on the buckle seat 14. The elastic buckle head 15 radially protrudes from the second inner hole wall 16 of the sealing body 20, and the cross section of the buckle head is hook-shaped. The buckle head is bent toward the outer edge of the sealing body 20. An elastic clamping groove 17 is provided between the elastic buckle head 15 and the buckle seat 14, and the elastic clamping groove 17 is provided away from the outer edge of the sealing body 20. This is conducive to ensuring that the elastic buckle 12 has a certain clamping force acting on the first inner hole wall 13, so that the sealing ring 4 can be stably and reliably fixed on the shell base 2.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations are possible in the above embodiments. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A motor comprising a housing (1), a cover (3), a housing base (2) disposed between the housing (1) and the cover (3), and a sealing ring (4) disposed between the housing base (2) and the cover (3), characterized in that The sealing ring (4) is provided with a positioning structure, and the housing seat (2) is provided with a positioning matching structure. The positioning structure corresponds to the positioning matching structure and is used to stably limit the sealing ring (4) between the housing seat (2) and the machine cover (3).

2. The motor according to claim 1, characterized in that The sealing ring (4) comprises a sealing body (20), and the positioning structure and the sealing body (20) are an integral structure.

3. The motor according to claim 2, characterized in that A plurality of extension ears (5) are provided on the inner edge or the outer edge of the sealing body (20), and a first connecting hole (6) is provided on the extension ear (5). The first connecting hole (6) is provided corresponding to the second connecting hole (7) of the shell base (2) and the third connecting hole (8) on the machine cover (3), and is used for the connecting member (18) to pass through the second connecting hole (7), the first connecting hole (6) and the third connecting hole (8) in sequence so that the connecting member (18) fixes the machine cover (3), the sealing ring (4) and the shell base (2).

4. The motor according to claim 3, characterized in that The positioning structure includes a positioning convex ring (9) provided on the extension ear (5), the positioning convex ring (9) is located at one end of the first connecting hole (6) facing the shell seat (2) and protrudes axially, the positioning matching structure includes a chamfer (19) at the opening of the second connecting hole (7), the positioning convex ring (9) is embedded in the second connecting hole (7) and fits the chamfer (19), and the inner diameter of the positioning convex ring (9) is adapted to the inner diameter of the second connecting hole (7).

5. The motor according to claim 2, characterized in that The positioning structure includes an outer flange (10) and / or an inner flange, and the outer flange (10) and the inner flange are respectively arranged on the outer edge and the inner edge of the sealing body (20). The positioning matching structure includes an outer step groove (11) and / or an inner step groove arranged on the shell seat (2), and the outer flange (10) and the inner flange are respectively snap-fitted with the corresponding outer step groove (11) and the inner step groove.

6. The motor according to claim 2, characterized in that The positioning structure comprises an outer flange (10) arranged on the outer edge of the sealing body (20) and a plurality of elastic snap fasteners (12) arranged at intervals on the inner edge of the sealing body (20); the positioning matching structure comprises an outer step groove (11) arranged on the shell seat (2) and a first inner hole wall (13) of the shell seat (2); the outer flange (10) is snap-fitted with the outer step groove (11), and the elastic snap fastener (12) is snap-fitted with the first inner hole wall (13).

7. The motor according to claim 6, characterized in that The elastic buckle (12) comprises a buckle seat (14) which is arranged on the second inner hole wall (16) of the sealing body (20) and radially protrudes, and an elastic buckle head (15) which is arranged on the buckle seat (14), wherein the elastic buckle head (15) radially protrudes from the second inner hole wall (16) of the sealing body (20), and the cross section of the buckle head is hook-shaped, and the buckle head is bent toward the outer edge of the sealing body (20), and an elastic clamping groove (17) is arranged between the elastic buckle head (15) and the buckle seat (14), and the elastic clamping groove (17) is arranged away from the outer edge of the sealing body (20).

8. The motor according to any one of claims 2 to 7, characterized in that The radial width B of the sealing body (20) is: B=(D0-d) / 2, the thickness B of the sealing body (20) is <(D0-d) / 5, and the height h of the outer flange (10) and the height of the inner flange of the positioning structure are: h>0.8B, wherein D0 is the outer diameter of the sealing body (20), and d is the inner diameter of the sealing body (20).

9. The motor according to claim 8, characterized in that One end of the shell seat (2) that cooperates with the machine cover (3) is a narrow end, and the end size of the narrow end is: (D1-D2) / D1<0.1, D1 is the outer diameter of the end of the narrow end, and D2 is the inner diameter of the end of the narrow end.

10. The motor according to claim 9, characterized in that The height of the positioning protrusion (9) on the sealing body (20) protruding from the corresponding surface of the extension ear (5) on the sealing body (20) is less than the thickness of the extension ear (5); the circumscribed circle diameter of the inner wall of the elastic buckle (15) on the sealing body (20) is equal to D1, and the inscribed circle diameter of the first inner hole wall (13) of the shell seat (2) and the inscribed circle diameter of the extension ear (5) are both equal to D2; when the extension ear (5) is arranged on the outer edge of the shell seat (2), D1<D2; when the extension ear (5) is arranged on the inner edge of the shell seat (2), D1>D2.

Images