CN117118125A - Motor - Google Patents

Abstract

The application discloses a motor, which comprises a fixed end cover and a rotary end cover assembly, wherein the rotary end cover assembly is rotatably arranged on one axial side of the fixed end cover, the motor further comprises a waterproof ring, the waterproof ring is arranged between the fixed end cover and the rotary end cover assembly, a rotary bending blocking structure in sealing fit with the inner wall of the rotary end cover assembly is constructed on the waterproof ring, and the rotary bending blocking structure of the waterproof ring can directly isolate foreign matters such as water dust through sealing fit with the inner wall of the rotary end cover assembly, so that the dustproof and waterproof effects are achieved.

Description

Motor

Technical Field

The application relates to the technical field of motors, in particular to a motor.

Background

The motor is generally applied to various industries, in the prior motor technology, the motor mainly comprises an inner rotor motor and an outer rotor motor according to a main body structure, and the motor type relates to the fields of alternating current asynchronous motors, reluctance switch motors, permanent magnet motors and the like. The rotating part of the inner rotor motor is arranged inside the inner rotor motor, and the outer stator is stationary; the rotating part of the outer rotor motor is arranged outside, and the stator inside the outer rotor motor is stationary.

In traditional external rotor motor structure, often because of dustproof and waterproof grade is low, lead to the motor to intake, advance the problem such as foreign matter, influence the safety problem when motor life-span and motor use.

Disclosure of Invention

The application aims to provide a motor and aims to solve the technical problem that the existing outer rotor motor is low in dustproof and waterproof grade.

In order to solve the above-mentioned problems, according to an aspect of the present application, an embodiment of the present application provides a motor, which includes a fixed end cover and a rotary end cover assembly, wherein the rotary end cover assembly is rotatably disposed at one axial side of the fixed end cover, the motor further includes a waterproof ring disposed between the fixed end cover and the rotary end cover assembly, and the waterproof ring is configured with a rotary bending blocking structure in sealing fit with an inner wall of the rotary end cover assembly.

In some embodiments, the rotary end cap assembly has an opening through which the swivel bend blocking structure sealingly engages an inner wall of the rotary end cap assembly.

In some embodiments, the waterproof ring has an inner bore, and the swivel bend blocking structure includes a tubular section extending axially from the inner bore toward the interior of the rotary end cap assembly, a first blocking section extending from an outer circumference of the tubular section toward an inner wall of the rotary end cap assembly, and a second blocking section extending from the first blocking section toward the waterproof ring, the second blocking section being in sealing engagement with the inner wall of the rotary end cap assembly.

In some embodiments, the opening is configured with a waterproof stage structure that can be combined with the swivel bend blocking structure to form a labyrinth seal structure.

In some embodiments, the waterproof platform structure comprises a first extension section extending radially outwards along the opening part of the opening and a second extension section connected with the first extension section and extending towards the waterproof ring along the axial direction, wherein the first blocking section is in fit with the first extension section, and the second blocking section is in fit with the second extension section.

In some embodiments, the fixed end cover is configured with a support column extending along the axial direction, the support column is sleeved with a winding iron core component, the support column is internally configured with a mounting through hole, a rotating shaft is inserted in the mounting through hole, and a sealing cover is arranged at the mouth part cover for sealing one end of the mounting through hole far away from the rotating end cover component.

In some embodiments, the mouth of the end of the mounting through hole remote from the rotary end cap assembly is configured with a counterbore in which the seal cap is embedded.

In some embodiments, the installation through hole is arranged at the bottom of the countersunk hole and is provided with an installation groove, the installation groove is provided with a first bearing, the rotating shaft is arranged in the first bearing in a penetrating way, one end of the rotating shaft, which faces the countersunk hole, is provided with a locking screw, and the diameter of an circumscribed circle of the head part of the locking screw is larger than the diameter of an inner hole of the first bearing of the rotating shaft; and/or the sealing cover is configured with a containing cavity for containing the locking screw.

In some embodiments, the opening of the installation through hole inside the rotary end cover assembly is provided with an installation groove, the installation groove is provided with a second bearing, the rotating shaft is arranged in the second bearing in a penetrating way, the periphery of the rotating shaft is provided with an annular clamping groove, the annular clamping groove is positioned on one side of the second bearing away from the support column, the annular clamping groove is provided with a clamping ring, and the outer diameter of the clamping ring is larger than the inner diameter of the inner hole of the second bearing.

In some embodiments, the rotary end cover assembly is provided with a penetrating hole, the rotating shaft extends out of the rotary end cover assembly through the penetrating hole, and a plurality of anti-rotating protrusions are arranged at the matching position of the rotating shaft and the penetrating hole.

Compared with the prior art, the motor has at least the following beneficial effects:

the embodiment of the application discloses a motor, which comprises a fixed end cover and a rotary end cover assembly, wherein the rotary end cover assembly is rotatably arranged on one axial side of the fixed end cover, the motor also comprises a waterproof ring, the waterproof ring is arranged between the fixed end cover and the rotary end cover assembly, a rotary bending blocking structure which is in sealing fit with the inner wall of the rotary end cover assembly is constructed on the waterproof ring, and water and dust are prevented from entering the motor through the rotary bending blocking structure, so that foreign matters such as water dust and the like can be directly isolated through the sealing fit between the rotary bending blocking structure of the waterproof ring and the inner wall of the rotary end cover assembly, the dustproof and waterproof effects are achieved, the integral process is simple, the problems of water inlet, foreign matters inlet and the like of the motor due to low dustproof and waterproof grades of the traditional outer rotor motor can be effectively improved, the sealing performance of the motor is improved, the dustproof and waterproof grades of the motor are improved, and the safety problems such as electric leakage and short circuit in the using process of the motor are effectively avoided.

In addition, the bending structure of the rotary bending blocking structure increases the surface area of the motor, so that the physical heat dissipation area is increased, the motor can effectively dissipate heat, and the service life of the motor is prolonged.

The foregoing description is only an overview of the present application, and is intended to provide a better understanding of the present application, as it is embodied in the following description, with reference to the preferred embodiments of the present application and the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a sectional view of a motor provided by an embodiment of the present application;

fig. 2 is a sectional view of an assembly of a rotating shaft, a winding core assembly and a fixed end cover of a motor according to an embodiment of the present application;

fig. 3 is a cross-sectional view of a stationary end cap of an electric motor provided by an embodiment of the present application;

fig. 4 is a schematic perspective view of a fixed end cover of a motor according to an embodiment of the present application;

fig. 5 is a cross-sectional view of a rotary end cap assembly of an electric motor according to an embodiment of the present application mated with a waterproof ring;

FIG. 6 is an enlarged view at A in FIG. 5;

FIG. 7 is a sectional view of a rotary end cap assembly of an electric motor provided in an embodiment of the present application;

fig. 8 is a schematic perspective view of a rotary end cover assembly of an electric motor according to an embodiment of the present application;

fig. 9 is a sectional view of a waterproof ring of a motor according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a rotating shaft of a motor according to an embodiment of the present application;

FIG. 11 is a schematic structural view of a sealing cover of a motor according to an embodiment of the present application;

fig. 12 is a schematic diagram of a general assembly structure of a motor according to an embodiment of the present application.

Reference numerals illustrate:

1. fixing the end cover; 11. a support column; 12. installing a through hole; 121. a countersunk hole; 122. installing a groove position; 2. a winding core assembly; 3. rotating the end cap assembly; 31. an opening; 32. a waterproof table structure; 321. a first extension; 322. a second extension; 33. a magnetic material; 34. penetrating holes; 35. a mating boss; 4. a rotating shaft; 41. anti-rotation protrusions; 42. an annular clamping groove; 5. a waterproof ring; 51. an inner bore; 52. a rotary bending blocking structure; 521. a tubular section; 522. a first blocking section; 523. a second blocking section; 6. sealing cover; 61. a receiving chamber; 71. a first bearing; 72. locking the screw; 73. a second bearing; 74. and a clasp.

Detailed Description

In order to further describe the technical means and effects adopted for achieving the preset aim of the application, the following detailed description refers to the specific implementation, structure, characteristics and effects according to the application of the application with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

In the description of the present application, it should be clear that the terms "first," "second," and the like in the description and claims of the present application and in the above-described figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order; the terms "vertical," "transverse," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "horizontal," and the like are used for indicating an orientation or a positional relationship based on that shown in the drawings, and are merely for convenience of description of the present application, and do not mean that the apparatus or element referred to must have a specific orientation or position, and thus should not be construed as limiting the present application.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

Example 1

As shown in fig. 1-12, an embodiment of the present application provides a motor, which includes a fixed end cover 1 and a rotary end cover assembly 3, wherein the rotary end cover assembly 3 is rotatably disposed on one axial side of the fixed end cover 1, the motor further includes a waterproof ring 5, the waterproof ring 5 is disposed between the fixed end cover 1 and the rotary end cover assembly 3, and a rotary bending blocking structure 52 which is in sealing fit with an inner wall of the rotary end cover assembly 3 is configured on the waterproof ring 5.

In this embodiment, the motor includes a fixed end cap 1, a winding core assembly 2, a rotating end cap assembly 3 and a rotating shaft 4, the rotating end cap assembly 3 is rotatably disposed on one axial side of the fixed end cap 1, specifically, the winding core assembly 2 is mounted on the fixed end cap 1, the rotating end cap assembly 3 is sleeved on the winding core assembly 2, the rotating shaft 4 is rotatably disposed on the fixed end cap 1 and is connected with the rotating end cap assembly 3 and extends to one side of the rotating shaft 4 far away from the fixed end cap 1, the rotating end cap assembly 3 is provided with a magnetic material 33, the winding core assembly 2 assembled on the fixed end cap 1 generates a rotating magnetic field effect with the magnetic material 33 on the rotating end cap assembly 3 after being electrified, at this time, the fixed end cap 1 is mounted and fixed on the ground or a fixed position such as a mounting seat through a plurality of mounting holes and bolts, the rotating end cap assembly 3 rotates to drive the rotating shaft 4 to rotate, and the rotating shaft 4 drives loads such as wind wheels to rotate; the motor of this embodiment sets up waterproof circle 5 between fixed end cover 1 and rotatory end cover subassembly 3 to be constructed on waterproof circle 5 with rotatory bending blocking structure 52 of the inner wall sealing fit of rotatory end cover subassembly 3, specifically, rotatory bending blocking structure 52 can form at least one with the inner wall cooperation department of rotatory end cover subassembly 3 and block the bending, prevent inside that water and dust from entering into the motor through blocking the bending, consequently can directly isolate foreign matter such as water dust through the sealing fit between rotatory bending blocking structure 52 of waterproof circle 5 and the inner wall of rotatory end cover subassembly 3, reach dustproof waterproof effect, whole simple process can effectively improve traditional external rotor motor dustproof waterproof grade low, and lead to the motor to advance water, advance the problem such as foreign matter, improve the sealing performance of motor and improve the dustproof waterproof grade of motor, effectively avoid the safety problems such as electric leakage, short circuit in the motor use.

In addition, the curved structure of the rotary bending blocking structure 52 increases the surface area of the motor, thereby increasing the physical heat dissipation area, so that the motor can effectively dissipate heat, and the service life of the motor is prolonged.

In some embodiments, the rotary end cap assembly 3 has an opening 31 and the swivel bend blocking structure 52 is in sealing engagement with the inner wall of the rotary end cap assembly 3 via the opening 31.

In this embodiment, the turning and bending blocking structure 52 of the waterproof ring 5 is in sealing engagement with the inner wall of the rotary end cap assembly 3 via the opening 31, and is specifically used for sealing the opening 31 of the rotary end cap assembly 3.

In some embodiments, the waterproof ring 5 is a sheet-like structure having an inner bore 51, and the swivel bend blocking structure 52 includes a tubular section 521 extending axially from the inner bore 51 toward the interior of the rotary end cap assembly 3, a first blocking section 522 extending from the outer periphery of the tubular section 521 toward the inner wall of the rotary end cap assembly 3, and a second blocking section 523 extending from the first blocking section 522 toward the waterproof ring 5, the second blocking section 523 being in sealing engagement with the inner wall of the rotary end cap assembly 3.

In this embodiment, the waterproof ring 5 is a sheet structure, specifically may be a disc structure, the waterproof ring 5 is provided with an inner hole 51, the rotary bending blocking structure 52 specifically includes a tubular section 521 extending from the inner hole 51 axially towards the inside of the rotary end cover assembly 3, a first blocking section 522 extending from the outer circumference of the tubular section 521 towards the inner wall of the rotary end cover assembly 3, and a second blocking section 523 extending from the first blocking section 522 towards the waterproof ring 5, and the rotary bending blocking structure 52 is formed by sequentially connecting the tubular section 521, the first blocking section 522 and the second blocking section 523, and the rotary bending blocking structure 52 is formed into a blocking groove, so that foreign matters such as water dust enter the blocking groove, and can be directly isolated, thereby achieving the functions of dust prevention and water prevention.

In addition, the number of the second blocking sections 523 may be plural, and the plural second blocking sections 523 are disposed at intervals in the length direction of the first blocking section 522, so that more blocking grooves may be formed, and the more the number of the blocking grooves, the better the dustproof and waterproof effects.

In some embodiments, the opening 31 of the rotary end cap assembly 3 is configured with a waterproof stage structure 32, and the waterproof stage structure 32 and the swivel bend blocking structure 52 can be combined to form a labyrinth seal structure.

In this embodiment, through the opening 31 department at rotatory end cover subassembly 3 is constructed with waterproof bench structure 32, through waterproof bench structure 32 and gyration blocking structure 52 combination formation labyrinth seal structure that bends, can directly isolate foreign matter such as water dust through labyrinth seal structure, reach dustproof waterproof's effect, whole simple process can effectively improve traditional external rotor motor dustproof waterproof grade low, and lead to the motor to advance water, advance the foreign matter scheduling problem, improve the sealing performance of motor and improve motor dustproof waterproof grade, effectively avoid the electric leakage in the motor use, safety problem such as short circuit.

In some embodiments, the waterproof stage structure 32 includes a first extension 321 extending radially outward along the mouth of the opening 31 of the rotary end cap assembly 3 and a second extension 322 connected to the first extension 321 and extending axially toward the waterproof ring 5, the first blocking section 522 being disposed in abutment with the first extension 321, and the second blocking section 523 being disposed in abutment with the second extension 322.

In this embodiment, the waterproof platform structure 32 specifically includes a first extension section 321 extending radially outwards from the opening of the opening 31 of the rotary end cover assembly 3 and a second extension section 322 connected with the first extension section 321 and extending axially towards the waterproof ring 5, and the first blocking section 522 is attached to the first extension section 321, and the second blocking section 523 is attached to the second extension section 322 to form a labyrinth seal structure.

In some embodiments, the fixed end cover 1 is configured with a support column 11 extending along the axial direction, the winding core assembly 2 is sleeved on the support column 11, the support column 11 is internally configured with a mounting through hole 12, the rotating shaft 4 is rotatably inserted in the mounting through hole 12, and the mouth cover of the mounting through hole 12, which is far away from one end of the rotating end cover assembly 3, is provided with a sealing cover 6.

In this embodiment, when waterproof circle 5 is fixed on fixed end cover 1, waterproof circle 5 passes through hole 51 cover to be established on support column 11, waterproof circle 5 is kept away from one side of rotatory end cover subassembly 3 and rotatory end cover subassembly 3 laminating setting, winding iron core subassembly 2 cover is located on support column 11, it is fixed to winding iron core subassembly 2 through support column 11, pivot 4 rotatable cartridge is located in installing through-hole 12, fix pivot 4 through installing through-hole 12, the oral area lid of installing through-hole 12 and keeping away from rotatory end cover subassembly 3 one end is equipped with sealed lid 6, it enters into the inside of motor from installing through-hole 12 and keeping away from rotatory end cover subassembly 3 one end through sealed lid 6 other foreign matter, reach dustproof waterproof effect, whole simple process can effectively improve traditional external rotor motor dustproof waterproof grade low, and lead to the motor to advance water, advance the foreign matter scheduling problem, improve the sealing performance of motor and improve motor dustproof waterproof grade, effectively avoid the safety problems such as electric leakage, short circuit in the motor use.

In some embodiments, the mouth of the end of the mounting through hole 12 remote from the rotary end cap assembly 3 is configured with a counterbore 121, and the seal cap 6 is embedded in the counterbore 121.

In this embodiment, the countersunk hole 121 is formed in the opening portion of the end, far away from the rotary end cover assembly 3, of the mounting through hole 12, the sealing cover 6 is embedded in the countersunk hole 121, the fixing firmness of the sealing cover 6 is improved, the sealing cover 6 can be prevented from falling off, the sealing cover 6 is prevented from being exposed out of the fixed end cover 1, and the aesthetic degree of the motor is improved.

In some embodiments, the mounting through hole 12 is configured with a mounting groove 122 with a shoulder at the bottom of the counter bore 121, the mounting groove 122 is provided with a first bearing 71, the rotating shaft 4 is arranged in the first bearing 71 in a penetrating way, one end of the rotating shaft 4 facing the counter bore 121 is provided with a locking screw 72, and the diameter of an circumcircle of the head of the locking screw 72 is larger than the diameter of an inner hole of the first bearing 71.

In this embodiment, the installation groove 122 with the shoulder is configured at the bottom of the installation through hole 12 located at the counter bore 121, the first bearing 71 is installed at the installation groove 122, the rotating shaft 4 is installed in the first bearing 71 in a penetrating manner, so that the rotating shaft 4 is rotatably installed in the installation through hole 12, and the locking screw 72 is installed at one end of the rotating shaft 4 facing the counter bore 121, so that the diameter of the circumcircle of the head of the locking screw 72 is larger than the diameter of the inner bore of the first bearing 71, and the rotating shaft 4 is prevented from moving in the installation through hole 12 towards one end far away from the counter bore 121.

In some embodiments, the sealing cover 6 is configured with the accommodating cavity 61 for accommodating the locking screw 72, so that the locking screw 72 is prevented from interfering with the sealing cover 6, and the sealing cover 6 can be in an integrated structure, thereby facilitating processing.

In some embodiments, the opening of the mounting through hole 12 inside the rotary end cap assembly 3 is configured with a mounting groove 122 having a shoulder, the mounting groove 122 is provided with a second bearing 73, the rotating shaft 4 is arranged in the second bearing 73 in a penetrating manner, the outer circumference of the rotating shaft 4 is provided with an annular clamping groove 42, the annular clamping groove 42 is positioned on one side of the second bearing 73 far away from the supporting column 11, the annular clamping groove 42 is provided with a clamping ring 74, and the outer diameter of the clamping ring 74 is larger than the inner diameter of the inner hole of the second bearing 73.

In the present embodiment, the mounting groove 122 with the shoulder is also formed at the opening of the mounting through hole 12 inside the rotary end cap assembly 3, and the second bearing 73 is mounted at the mounting groove 122, the two mounting grooves 122 limit the axial distance between the second bearing 73 and the first bearing 71, when the rotary shaft 4 is mounted on the second bearing 73 and the first bearing 71, the locking screw 72 limits the rotary shaft 4 to move in the axial direction from the first bearing 71 to the second bearing 73, and the annular clamping groove 42 is formed at the periphery of the rotary shaft 4, and the outer diameter of the clamping ring 74 is larger than the inner diameter of the inner hole of the second bearing 73, so that the rotary shaft 4 is prevented from moving in the axial direction from the second bearing 73 to the first bearing 71, and the rotary shaft 4 is prevented from moving in the axial direction from both ends in the mounting through hole 12, thereby improving the running stability of the motor.

In some embodiments, the rotary end cover assembly 3 has a through hole 34, the rotary shaft 4 extends out of the rotary end cover assembly 3 through the through hole 34, a plurality of anti-rotation protrusions 41 are arranged at the matching position of the rotary shaft 4 and the through hole 34, the anti-rotation protrusions 41 can be strip-type anti-rotation protrusions, point-type anti-rotation protrusions and the like, and a plurality of strip-type anti-rotation protrusions and point-type anti-rotation protrusions on the rotary shaft 4 are used for interference fit with the through hole 34 of the rotary end cover assembly 3. When the rotary end cover assembly 3 rotates, the rotary shaft 4 can be driven to rotate, so that loads such as wind wheels on the rotary shaft 4 are driven to operate, and the reliability of motor power transmission is improved.

In some embodiments, a matching boss 35 is configured at the mouth of at least one side of the axial direction of the through hole 34, and the matching boss 35 lengthens the interference fit length of the through hole 34 and the rotating shaft 4, so as to further improve the reliability of motor power transmission.

In summary, it is easily understood by those skilled in the art that the above-mentioned advantageous features can be freely combined and overlapped without conflict.

While the application has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the application. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims (10)

1. The motor comprises a fixed end cover and a rotary end cover assembly, wherein the rotary end cover assembly is rotatably arranged on one axial side of the fixed end cover, and the motor is characterized by further comprising a waterproof ring, the waterproof ring is arranged between the fixed end cover and the rotary end cover assembly, and a rotary bending blocking structure which is in sealing fit with the inner wall of the rotary end cover assembly is arranged on the waterproof ring.

2. The electric machine of claim 1, wherein the rotary end cap assembly has an opening through which the swivel bend blocking structure sealingly engages an inner wall of the rotary end cap assembly.

3. The electric machine of claim 2, wherein the water ring has an inner bore, the swivel bend blocking structure includes a tubular section extending axially from the inner bore toward the interior of the rotary end cap assembly, a first blocking section extending from an outer periphery of the tubular section toward an inner wall of the rotary end cap assembly, and a second blocking section extending from the first blocking section toward the water ring, the second blocking section being in sealing engagement with the inner wall of the rotary end cap assembly.

4. A motor as claimed in claim 3, wherein the opening is configured with a waterproof stand structure which can be combined with the swivel bend blocking structure to form a labyrinth seal.

5. The motor of claim 4, wherein the waterproof table structure comprises a first extension extending radially outward along the mouth of the opening and a second extension connected to the first extension and extending axially toward the waterproof ring, the first blocking section being disposed in registry with the first extension, the second blocking section being disposed in registry with the second extension.

6. The motor of claim 1, wherein the fixed end cap is configured with an axially extending support post, the support post is sleeved with a winding core assembly, an installation through hole is configured in the support post, a rotating shaft is inserted in the installation through hole, and a sealing cover is arranged at a mouth cover of the installation through hole, which is far away from one end of the rotating end cap assembly.

7. The motor of claim 6, wherein the mouth of the mounting through hole at an end remote from the rotary end cap assembly is configured with a counterbore, and the sealing cap is embedded in the counterbore.

8. The motor of claim 7, wherein the mounting through hole is located at the bottom of the countersunk hole and is provided with a mounting groove, the mounting groove is provided with a first bearing, the rotating shaft is arranged in the first bearing in a penetrating way, one end of the rotating shaft, which faces the countersunk hole, is provided with a locking screw, and the diameter of an circumscribed circle of the head part of the locking screw is larger than the diameter of an inner hole of the first bearing; and/or the sealing cover is configured with a containing cavity for containing the locking screw.

9. The motor of claim 6, wherein the opening of the mounting through hole in the rotary end cap assembly is provided with a mounting groove, the mounting groove is provided with a second bearing, the rotating shaft is arranged in the second bearing in a penetrating manner, the periphery of the rotating shaft is provided with an annular clamping groove, the annular clamping groove is positioned on one side of the second bearing away from the support column, the annular clamping groove is provided with a clamping ring, and the outer diameter of the clamping ring is larger than the inner diameter of the inner hole of the second bearing.

10. The motor of claim 6, wherein the rotary end cap assembly has a through hole, the shaft extends out of the rotary end cap assembly through the through hole, and a plurality of anti-rotation protrusions are disposed at the position where the shaft is matched with the through hole.