Sealing structure

Abstract

The invention relates to the field of sealing, and provides a sealing structure which is applied to a rotating part, the rotating part comprises a rotor and a bearing box, a rotating shaft of the rotor is in running fit with a bearing in the bearing box, and the sealing structure comprises a first annular seal, a second annular seal, an isolation cavity and a sealing unit. The first annular seal and the rotating shaft are coaxially arranged, the first annular seal is located on the side, close to the rotor, of the bearing box, and the first annular seal is used for forming seal between the bearing box and the rotating shaft; the second annular seal and the rotating shaft are coaxially arranged, the second annular seal is located on the side, close to the rotor, of the first annular seal, and the second annular seal is used for forming seal between the bearing box and the rotating shaft; the isolation cavity is located between the first annular seal and the second annular seal and communicates with the atmosphere. The sealing unit is arranged between the isolation cavity and the first annular seal. According to the sealing structure, the sealing unit is additionally arranged in the bearing box, so that lubricating oil mist in the bearing box can be effectively prevented from entering the motor.

Description

Technical Field

[0001] The invention relates to the field of sealing, and in particular to a sealing structure. Background Art

[0002] High-voltage motors have been widely used in many fields. Large and medium-sized high-voltage motors usually adopt bearing structures, and their internal lubrication and cooling are crucial to the stability and long-term operation of the motor.

[0003] In the prior art, the motor bearing box adopts two floating labyrinth seal structures, which are used to seal the bearing oil chamber and the external isolation chamber, and the connection between the isolation chamber and the motor housing. However, since the motor rotor is designed with a cooling circulation fan, the high-speed rotation of the rotor during motor operation will form a negative pressure area at the rotor end. This negative pressure will have a certain suction effect on the lubricating oil mist in the bearing box, causing the oil mist to enter the isolation chamber along the gap of the floating labyrinth seal, and even be further sucked into the motor. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a sealing structure to improve the sealing effect.

[0005] To achieve the above-mentioned object and other related objects, the present invention provides a sealing structure applied to a rotating member, wherein the rotating member includes a rotor and a bearing box, wherein the rotating shaft of the rotor is rotatably matched with the bearing in the bearing box, and the sealing structure includes:

[0006] a first annular seal, arranged coaxially with the rotating shaft, the first annular seal being located at a side of the bearing housing close to the rotor, and the first annular seal being used to form a seal between the bearing housing and the rotating shaft;

[0007] a second annular seal, arranged coaxially with the rotating shaft, the second annular seal being located on a side of the first annular seal close to the rotor, and the second annular seal being used to form a seal between the bearing housing and the rotating shaft;

[0008] an isolation chamber, located between the first annular seal and the second annular seal, the isolation chamber covers the axial direction of the rotating shaft, and the isolation chamber is communicated with the atmosphere;

[0009] A sealing unit is disposed between the isolation chamber and the first annular seal, and the sealing unit is used to form a seal between the bearing box and the rotating shaft.

[0010] In a specific embodiment of the present invention, the sealing unit includes a spiral sealing assembly, which is disposed on the rotating shaft and rotates with the rotating shaft, and the rotation direction of the spiral sealing assembly with the rotating shaft is to prevent the internal material of the bearing box from leaking into the isolation chamber.

[0011] In a specific embodiment of the present invention, the sealing unit further comprises an annular sealing seat, the inner wall of the annular sealing seat is sealingly matched with the outer periphery of the spiral sealing assembly.

[0012] In a specific embodiment of the present invention, an end surface of the spiral sealing component close to the isolation chamber is flush with an end surface of the annular sealing seat close to the isolation chamber.

[0013] In a specific embodiment of the present invention, the bearing box has a mounting surface for axial mounting of the annular seal seat, and an end surface of the spiral seal assembly close to the first annular seal is axially spaced from the mounting surface.

[0014] In a specific embodiment of the present invention, the axial distance between the spiral seal assembly and the mounting surface is 1.2-1.5 times the axial leakage of the rotor.

[0015] In a specific embodiment of the present invention, the spiral sealing assembly comprises:

[0016] A spiral seal body, composed of two identical annular halves, the spiral seal body being provided with radial screws for pressing against the rotating shaft;

[0017] A pressure plate, composed of two identical annular halves, the pressure plates being mounted on both end surfaces of the spiral seal body respectively;

[0018] Wherein, the boundary of the annular half of the pressure plate and the boundary of the annular half of the spiral sealing body are offset by 90 degrees in the circumferential direction.

[0019] In a specific embodiment of the present invention, the spiral seal body is provided with an annular mounting groove for flush embedding of the pressure plate, the outer diameter of the pressure plate is smaller than the outer diameter of the spiral seal body, and the inner diameter of the pressure plate is larger than the inner diameter of the spiral seal body.

[0020] In a specific embodiment of the present invention, an air path for connecting the isolation chamber and the atmosphere is provided on the bearing box, and a filter is detachably connected to one end of the air path close to the atmosphere, and an air filter element is provided in the filter.

[0021] In a specific embodiment of the present invention, both the first annular seal and the second annular seal are floating labyrinth seals arranged on the bearing housing.

[0022] The present invention proposes a sealing structure, which can effectively prevent the lubricating oil mist in the bearing box from entering the interior of the motor through an additional sealing unit in the bearing box, avoiding its adhesion to the motor rotor and stator coils, thereby preventing the motor coil temperature from rising and the insulation erosion of the iron core and coil ends and other adverse phenomena. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0024] Figure 1 is a structural schematic diagram of a sealing structure in one embodiment of the present invention;

[0025] Figure 2 In one embodiment of the present invention Figure 1 A magnified view of part A;

[0026] Figure 3 A schematic diagram of the cooperation between a bearing and a spiral seal assembly in one embodiment of the present invention;

[0027] Figure 4 is a schematic structural diagram of a spiral seal body in one embodiment of the present invention;

[0028] Figure 5 It is a schematic structural diagram of a pressing plate in one embodiment of the present invention;

[0029] Figure 6 is a cross-sectional view of a pressing plate in one embodiment of the present invention;

[0030] Figure 7 FIG. 4 is a cross-sectional view of a spiral seal body in one embodiment of the present invention.

[0031] Explanation of the reference numerals in the accompanying drawings: 10. bearing box; 11. bearing; 12. oil flinger; 13. bearing end cover; 14. isolation chamber; 15. air path; 20. rotating shaft; 21. rotor circulation fan; 30. guide plate; 40. first annular seal; 50. second annular seal; 60. spiral seal assembly; 61. spiral seal body; 62. pressure plate; 63. radial screw; 64. annular mounting groove; 70. annular seal seat; 80. filter; 81. air filter element. DETAILED DESCRIPTION

[0032] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0033] It should be noted that the illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention, and thus the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0034] With the rapid development of heavy industries such as petroleum, electricity, and chemicals, high-voltage motors have been widely used in many fields, especially in situations where high speed, high power, and low energy consumption are required. The frequency of use is increasing. Large and medium-sized high-voltage motors usually use a bearing 11 structure, and its internal lubrication and cooling are crucial to the stability and long-term operation of the motor.

[0035] In the bearing 11, an oil slinger 12 is usually designed to achieve uniform distribution of lubricating oil. When the motor runs at a high speed, the oil slinger 12 rotates at a high speed, which can not only effectively throw out the lubricating oil to lubricate the surface of the bearing 11, but also may generate oil mist inside the bearing box 10 due to the high-speed rotation. These oil mists will form a slightly positive pressure state in the bearing box 10, while one end of the motor housing is in a slightly negative pressure state. This pressure difference may cause the lubricating oil mist to penetrate into the motor.

[0036] The motor bearing box 10 adopts two floating labyrinth seal structures, which are used to seal the connection between the oil chamber of the bearing 11 and the external isolation chamber 14, and the isolation chamber 14 and the motor housing. However, since the motor's internal rotor is designed with a cooling circulation fan, the high-speed rotation of the rotor during motor operation will form a negative pressure area at the rotor end. This negative pressure will have a certain suction effect on the lubricating oil mist in the bearing box 10, causing the oil mist to enter the isolation chamber 14 along the gap of the floating labyrinth seal, and even be further sucked into the motor.

[0037] As the lubricating oil mist enters the motor, it tends to adhere to the surface of the rotor and stator coils, causing a series of negative effects. First, the accumulation of lubricating oil mist increases the temperature of the motor coils, thereby affecting the heat dissipation performance of the motor. Second, impurities in the lubricating oil mist may corrode the insulation layer of the motor core and the coil ends. Long-term operation may cause the insulation performance to deteriorate, and even cause motor failure, seriously affecting the long-term safe and stable operation of the motor.

[0038] Therefore, in order to solve the problem of lubricating oil mist leakage in the bearing 11, how to improve the sealing structure design, optimize the internal pressure difference of the bearing box 10, and prevent the lubricating oil mist from entering the motor has become an important research direction in current motor design and maintenance.

[0039] like Figure 1-7 As shown, the present invention provides a sealing structure applied to a rotating part, which can be a high-voltage, high-speed, increased-safety three-phase asynchronous motor.

[0040] The rotating member includes a rotor and a bearing box 10. The rotating shaft 20 of the rotor is rotatably matched with the bearing 11 in the bearing box 10. The sealing structure includes a first annular seal 40, a second annular seal 50, an isolation chamber 14 and a sealing unit.

[0041] The first annular seal 40 is coaxially arranged with the rotating shaft 20. The first annular seal 40 is located on the side of the bearing housing 10 close to the rotor. The first annular seal 40 is used to form a seal between the bearing housing 10 and the rotating shaft 20. It is used to form a first sealing barrier between the bearing housing 10 and the rotating shaft 20 to prevent the lubricating oil mist in the bearing housing 10 from directly entering the isolation chamber 14. It is the initial line of defense against oil mist leakage, ensuring that the oil mist is kept in the oil chamber of the bearing 11 as much as possible.

[0042] The second annular seal 50 is coaxially arranged with the rotating shaft 20. The second annular seal 50 is located on the side of the first annular seal 40 close to the rotor. The second annular seal 50 is used to form a seal between the bearing housing 10 and the rotating shaft 20. A second sealing barrier is formed between the bearing housing 10 and the rotating shaft 20 to further prevent the oil mist from penetrating from the isolation chamber 14 into the interior of the motor. It provides double protection and reduces the risk of oil mist leakage.

[0043] The isolation chamber 14 is located between the first annular seal 40 and the second annular seal 50. The isolation chamber 14 covers the axial direction of the rotating shaft 20 and is connected to the atmosphere. The isolation chamber 14 serves as a buffer area between the two seals to balance the pressure difference and prevent the negative pressure from further sucking the oil mist into the motor. At the same time, since the isolation chamber 14 is connected to the external atmosphere, the adsorption effect of the negative pressure on the oil mist can be reduced, which helps to maintain the stability of the oil mist in the chamber.

[0044] The sealing unit is disposed between the isolation chamber 14 and the first annular seal 40, and is used to form a seal between the bearing housing 10 and the rotating shaft 20. During the operation of the motor, the sealing unit further enhances the sealing effect between the bearing housing 10 and the rotating shaft 20, preventing the oil mist from penetrating into the isolation chamber 14 through the first annular seal 40, thereby ensuring the long-term stable operation of the motor. Its design can effectively reduce the influence of the suction effect caused by high speed on the penetration of oil mist.

[0045] The rotating parts specifically include accessories such as an oil slinger 12 , a rotor circulation fan 21 , a guide plate 30 , and a bearing end cover 13 .

[0046] The oil slinger 12 is fixed on the rotating shaft 20 and moves with the high-speed rotation of the rotating shaft 20. It is used to evenly distribute the lubricating oil on the surface of the bearing 11 to ensure that the bearing 11 is fully lubricated. Its rotation also generates a certain centrifugal force to return the lubricating oil to the oil chamber, reducing the generation of excess oil mist.

[0047] The rotor circulation fan 21 is installed at the end of the rotor to cool the motor. The high temperature generated by the motor during operation is reduced through air circulation, especially to prevent the motor stator and rotor coil from overheating. However, it may also cause negative pressure at high speeds, promoting oil mist penetration, so it needs to be used in conjunction with a sealing structure.

[0048] The guide plate 30 is installed inside the motor to guide the cooling airflow, help the rotor circulation fan 21 to guide the airflow, optimize the cooling effect, and prevent the airflow from directly acting on the sealing structure, reducing the possibility of the sealing unit being disturbed by the airflow.

[0049] The bearing end cover 13 is used to seal the end of the bearing box 10, protect the bearing 11 and the internal lubrication system, prevent the entry of external dust or impurities, and cooperate with the sealing unit to provide structural support and sealing effect.

[0050] like Figure 1 , 2As shown, the sealing unit includes a spiral seal assembly 60, which is arranged on the rotating shaft 20 and rotates with the rotating shaft 20. The rotation direction of the spiral seal assembly 60 with the rotating shaft 20 is to prevent the internal material of the bearing box 10 from leaking into the isolation chamber 14. The spiral seal body 61 adopts a horizontally split trapezoidal spiral sleeve structure. When designing, the spiral angle, spiral pitch and geometric shape of the trapezoidal cross section are determined according to the rotation speed of the motor, the size of the annular seal seat 70, and the journal structure of the rotating shaft 20. This design ensures that the sealing assembly can adapt to high-speed rotation conditions. The spiral seal assembly 60 is fixed on the rotating shaft 20 and moves synchronously with the rotation of the rotating shaft 20. This structure is designed to use the rotation direction to control the flow of oil mist in the high-speed working environment of the bearing box 10. The rotation direction of the spiral seal assembly 60 is opposite to the direction in which the oil mist and lubricating oil in the bearing box 10 may leak. As the shaft 20 rotates at high speed, the trapezoidal spiral sleeve of the spiral seal body 61 will generate a reverse thrust to push the leaked oil mist and lubricating oil back into the bearing box 10. In this way, it plays a role similar to a "return valve" in structure, effectively reducing the possibility of oil mist leaking outward.

[0051] The trapezoidal spiral sleeve design of the spiral seal body 61 gives it a larger surface area, which can form a stronger dynamic sealing effect between the rotating shaft 20 and the annular sealing seat 70. When the motor is running at high speed, the spiral seal assembly 60 continuously strengthens the blocking effect on oil mist, especially under high speed and high load conditions, which can significantly improve the sealing performance. The split structure of the trapezoidal spiral sleeve makes it more convenient to process and maintain, and the split design can improve the installation accuracy of the assembly, so that the spiral seal body 61 and the rotating shaft 20 are more closely matched, thereby improving the overall sealing effect.

[0052] The width of the spiral tooth is s1, the width of the spiral groove is s2, the groove depth is h1, the width of the spiral seal body 61 is L, the outer periphery of the spiral seal body 61 matches the inner periphery of the annular seal seat 70, and the matching tolerance is a clearance match, which is mainly used for sealing between the spiral seal body 61 and the annular seal seat 70, and effectively prevents the leakage of the micro-positive pressure lubricating oil mist in the bearing box 10 into the isolation chamber 14.

[0053] like Figure 1 , 2As shown, the sealing unit also includes an annular sealing seat 70, and the inner ring wall of the annular sealing seat 70 is sealed and matched with the outer periphery of the spiral sealing assembly 60. The inner ring wall of the annular sealing seat 70 is sealed and matched with the outer periphery of the spiral sealing assembly 60, and is designed as a clearance fit structure. This can ensure that the spiral sealing assembly 60 does not generate excessive friction when rotating with the rotating shaft 20, and can maintain the sealing effect and prevent oil mist from leaking from the rotating shaft 20. The outer periphery of the annular sealing seat 70 is processed into a straight-mouth step structure. This design allows the annular sealing seat 70 to fit tightly with the end face of the bearing box 10, and radial positioning and fixing are performed through a small clearance fit to ensure that it is installed firmly and stably. The annular sealing seat 70 is designed as a horizontal split structure for easy installation and maintenance. The split design ensures that the sealing seat can be replaced or repaired without disassembling the entire device. By turning the end face of the bearing box 10, a straight-mouth step structure is formed, so that the inner periphery of the step of the bearing box 10 is matched with the outer periphery of the annular sealing seat 70. This small clearance fit not only ensures the stability of the seal seat, but also provides accurate positioning in the radial direction to prevent displacement or shaking during rotation.

[0054] The end face of the bearing housing 10 after turning is drilled and tapped to fix the annular seal seat 70 on the bearing housing 10. These holes are designed with stepped holes so that screws can fasten the annular seal seat 70 to the bearing housing 10 body, providing a stronger mechanical connection to ensure that it will not loosen during operation.

[0055] A plurality of stepped holes are drilled on the end face of the annular seal seat 70, which cooperate with the screw holes on the end face of the bearing box 10 for screw fixing. The design of the stepped holes enables the screws to effectively distribute the pressure, avoiding excessive local stress that causes the seal seat to deform or affect the sealing performance.

[0056] A clearance fit is adopted between the inner circumferential wall of the annular sealing seat 70 and the outer circumferential wall of the spiral sealing body 61. The main function of this matching design is to ensure that a stable sealing effect can be formed between the two to prevent oil mist from leaking when the rotating shaft 20 runs at high speed. At the same time, the clearance fit provides a certain flexibility and reduces the wear caused by thermal expansion or other stresses. The matching of the annular sealing seat 70 and the spiral sealing assembly 60 not only improves the static sealing performance, but also enhances the dynamic sealing effect. When the spiral sealing assembly 60 rotates with the rotating shaft 20, the annular sealing seat 70 maintains a stable gap with it. This design can effectively prevent the leakage of oil mist, especially under the condition of high-speed operation of the motor, to ensure the continuity of the sealing effect.

[0057] like Figure 1 , 2As shown, the end face of the spiral seal assembly 60 close to the isolation chamber 14 is flush with the end face of the annular seal seat 70 close to the isolation chamber 14. The flush design simplifies the assembly process and reduces assembly errors caused by inaccurate component positions. This is crucial to ensure the stability and reliability of the entire sealing system, especially in complex industrial equipment, and can reduce the probability of failure.

[0058] like Figure 1 , 2 As shown, the bearing box 10 has a mounting surface for the annular seal seat 70 to be axially mounted, and the end surface of the spiral seal assembly 60 close to the first annular seal 40 is axially spaced from the mounting surface, that is, a certain axial distance is maintained between the two. This design is mainly to prevent axial eccentric wear, that is, contact friction between the seal seat or the seal assembly and the bearing box 10 that may occur during operation due to the pressure of the bearing box 10 or the rotation of the spiral seal assembly 60. The axial spacing arrangement can effectively reduce contact and avoid local wear caused by friction.

[0059] In a specific embodiment of the present invention, the axial spacing between the spiral seal assembly 60 and the mounting surface is 1.2-1.5 times the axial movement of the rotor. When the rotor is running at high speed, there will be a certain amount of axial movement, that is, axial movement caused by mechanical load, thermal expansion or speed change. If the spacing between the spiral seal assembly 60 and the mounting surface is insufficient, the spiral seal body 61 will cause friction with the mounting surface or other fixed parts when the rotor moves, thereby causing wear and affecting the life of the equipment. Setting the axial spacing to 1.2-1.5 times the axial movement of the rotor ensures that even when the rotor moves within the maximum movement range, the spiral seal assembly 60 will not directly contact the mounting surface. This extra space provides a buffer and redundant design, further reducing the risk of collision or friction.

[0060] In the design, the maximum safety distance between the outer end surface of the spiral seal body 61 and the mounting surface of the bearing box 10 is also set at 1.2-1.5 times the axial displacement of the rotor. This ensures that even if axial displacement occurs under extreme working conditions, the spiral seal assembly 60 can still avoid any direct contact with the mounting surface, preventing seal failure due to contact wear.

[0061] The proper safety distance is not only to prevent mechanical friction, but also to ensure that the sealing component can operate normally under different working conditions. The setting of the spacing ensures that the spiral seal body 61 maintains its designed sealing effect during operation, avoiding poor sealing or leakage caused by component deformation or friction.

[0062] like Figure 3 As shown, the spiral seal assembly 60 includes a spiral seal body 61 and a pressure plate 62:

[0063] like Figure 4 As shown, the spiral seal body 61 is composed of two identical annular halves, that is, the spiral seal body 61 is a split structure, and the spiral seal body 61 is provided with a radial screw 63 for pressing the rotating shaft 20. Figure 5 As shown, the pressure plate 62 is composed of two identical annular halves, that is, the pressure plate 62 is a split structure, and the pressure plate 62 is respectively installed on the two end surfaces of the spiral seal body 61. The spiral seal body 61 and the pressure plate 62 are both composed of two identical annular halves. This split structure can greatly improve the convenience of installation and maintenance, especially when the sealing assembly needs to be installed on the already installed rotating shaft 20 or other shaft-type equipment, avoiding the trouble of completely disassembling the equipment.

[0064] A plurality of radial screws 63 are arranged in the middle of the outer peripheral wall of the spiral seal body 61, which are installed by drilling and tapping, and are mainly used to firmly fix the spiral seal body 61 on the motor shaft. The radial screws 63 can provide a stable radial support to prevent the spiral seal body 61 from being displaced relative to the rotating shaft 20 during operation. The inner peripheral wall of the spiral seal body 61 and the rotating shaft 20 are matched with a small gap, which means that in the radial direction, the spiral seal body 61 can be accurately positioned on the rotating shaft 20, maintaining the coaxiality of the two and ensuring the sealing effect. The small gap fit helps to prevent the seal body from being unnecessarily offset or deformed due to the rotation of the rotating shaft 20.

[0065] like Figure 6 As shown, the pressure plate 62 is designed as a horizontally split straight-mouthed stepped conical ring structure, and the tapered straight-mouthed outer peripheral wall of the pressure plate 62 is matched with the inner peripheral wall of the right-angled step groove on the end face of the spiral seal with a larger clearance, while the tapered surface of the pressure plate 62 is matched with the tapered surface of the step groove on the end face of the spiral seal with a smaller clearance. This differentiated matching method ensures that the overall combination of the spiral seal body 61 and the pressure plate 62 has a certain assembly flexibility, and at the same time has close contact at key positioning and fixing positions, thereby improving the stability of the structure and the reliability of the seal. The size of the matching tolerance directly affects the relative movement or fixation between parts. For the spiral seal body 61 and the pressure plate 62, two types of larger clearance matching and smaller clearance matching are designed, which are used for different combination positions respectively. This design allows a certain flexibility during the installation and assembly process, while maintaining the necessary tight fit at key positions to ensure the sealing effect.

[0066] The boundary between the annular half of the pressure plate 62 and the annular half of the spiral seal body 61 is offset by 90 degrees in the circumferential direction. The interface between the pressure plate 62 and the spiral seal body 61 is offset by 90 degrees in the circumferential direction. This design is to improve the structural strength and stability and prevent the overall rigidity from being insufficient or loose due to the connection boundary line at the same position. The pressure plate 62 and the spiral seal body 61 are tightly connected and fixed by installing bolts, which enhances the firmness between the components, and the use of step holes facilitates positioning, ensuring that the sealing component will not loosen or shift in a high-speed, high-stress environment.

[0067] like Figure 7 As shown, the spiral seal body 61 is provided with an annular mounting groove 64 for the pressure plate 62 to be flushly embedded. The annular mounting groove 64 provided on the spiral seal body 61 allows the pressure plate 62 to be flushly embedded, ensuring that the pressure plate 62 can be kept on the same plane as the outer surface of the spiral seal body 61. With this design, the overall appearance can be more compact, while also reducing the protruding parts after assembly, avoiding possible external interference of the equipment during operation. The annular mounting groove 64 is designed as a straight-mouthed stepped conical groove, and its conical structure can provide a more stable positioning function in the radial direction. At the same time, the stepped groove makes it easier to align the pressure plate 62 and the seal body during the assembly process, thereby improving the assembly accuracy and stability. The presence of the conical structure can guide the pressure plate 62 to be embedded in place more smoothly.

[0068] The outer diameter of the pressure plate 62 is smaller than the outer diameter of the spiral seal body 61. This design ensures that the pressure plate 62 will not interfere with the outside of the spiral seal body 61 after installation, avoiding external friction or collision during operation. In addition, the smaller outer diameter design further reduces the external dimensions of the component and improves the compactness of the overall structure. The inner diameter of the pressure plate 62 is larger than the inner diameter of the spiral seal body 61. This design ensures that during the mating process of the spiral seal body 61 and the rotating shaft 20, the pressure plate 62 will not interfere with the normal operation of the rotating shaft 20, and also allows the spiral seal body 61 and the pressure plate 62 to act more freely and independently on their respective mating parts, thereby improving the overall radial stability.

[0069] The end surface at the bottom of the annular mounting groove 64 is drilled and tapped. These threaded holes are mainly used to install and fix the pressure plate 62 to ensure that it can be firmly connected to the spiral seal body 61 under high pressure or high speed operation. This design can provide strong axial fixation to prevent the pressure plate 62 from loosening or displacement during use. Due to the presence of the annular mounting groove 64, the screws can be more conveniently placed in the threaded holes, reducing the complexity of assembly and maintenance. Especially when the pressure plate 62 needs to be replaced, this design can greatly improve the efficiency of the operation.

[0070] like Figure 1As shown, the bearing box 10 is provided with an air path 15 for connecting the isolation chamber 14 and the atmosphere, and a filter 80 is detachably connected to one end of the air path 15 close to the atmosphere, and an air filter element 81 is arranged in the filter 80. By installing the filter 80 at the entrance of the bearing box 10 and the motor air path 15, pollutants such as dust and particles can be effectively prevented from entering the bearing box 10 and the motor. If these particles enter the system, they will increase the wear of mechanical parts, cause the motor to have a reduced operating efficiency, and even cause failures. The use of the filter 80, especially in an environment with poor air quality, can greatly extend the safe operation cycle of the motor and reduce the maintenance frequency. The air filter element 81 in the filter 80 can effectively filter impurities in the air, especially in dusty factories or construction sites, and this design is crucial. It can not only extend the life of the motor, but also improve the working stability of the motor and reduce the risk of failure caused by air pollution.

[0071] The filter 80 is connected to the inlet end of the gas circuit 15 by a flange-type disassembly. This design allows the filter 80 to be easily disassembled and replaced, which is convenient for maintenance and upkeep. This connection method can also ensure the firmness of the connection and ensure that the filter 80 will not loosen during the operation of the equipment. Maintenance personnel can easily replace or clean the filter 80 without disassembling the bearing box 10 or other parts of the motor, which greatly reduces the maintenance workload and time. In addition, the standardized design of the flange can also make the size and structure of the filter 80 flexibly applied in different occasions to meet the needs of various environments.

[0072] like Figure 1 As shown, the first annular seal 40 and the second annular seal 50 are both floating labyrinth seals arranged on the bearing box 10. A floating labyrinth seal is a sealing device consisting of a plurality of annular components and channels. These components are arranged with set gaps to form a labyrinth-like channel, through which air or liquid will undergo multiple turns when passing, thereby effectively preventing direct leakage. Due to the floating nature of its structure, the tightness of the seal can be automatically adjusted according to the working conditions to reduce friction and wear. Due to the design of the labyrinth structure, the fluid needs to undergo multiple turns and eddies when passing through the seal, greatly reducing the possibility of leakage. This form of sealing can effectively prevent lubricating oil or other media from leaking from the bearing box 10, thereby protecting the internal environment of the equipment.

[0073] The installation method of the above structure is:

[0074] First, the installation part of the first annular seal 40 of the bearing box 10 and the inlet end face of the air path 15 are processed, and the lower body of the bearing box 10 and the lower bearing 11 are reinstalled. The dimensional tolerance of each processed part is checked and measured. The annular seal seat 70 is installed and the concentricity of the annular seal seat 70 and the rotating shaft 20 is checked to see if it meets the tolerance requirements. If not, the annular seal seat 70 needs to be processed and adjusted until it meets the coaxiality tolerance; measure and adjust the magnetic alignment of the motor rotor.

[0075] Secondly, install the spiral seal body 61 and the pressure plate 62. The inner end face of the spiral seal body 61 should be aligned with the inner end face of the annular seal seat 70. A large safety distance should be left between the outer end face of the spiral seal body 61 and the installation surface. The safety distance should be 1.2-1.5 times the axial displacement size of the rotor to prevent the spiral seal assembly 60 from rubbing against the end face of the bearing box 10 to ensure the best spiral sealing effect. When installing the pressure plate 62, stagger the center plane of the pressure plate 62 and the center plane of the spiral body by 90 degrees, install and tighten the fastening bolts of the spiral seal assembly 60, and use a torque wrench to tighten the bolts diagonally. After tightening, check and adjust the concentricity of the spiral seal body 61 and the shaft to ensure the best matching tolerance between the spiral seal body 61 and the annular seal seat 70; tighten the fastening screws in the spiral seal body 61.

[0076] Finally, the filter 80 and the air filter element 81 are installed and connected to the bearing box 10 body, and the bolts between the bearing box 10 body and the motor housing are tightened.

[0077] The present invention proposes a sealing structure, which can effectively prevent the lubricating oil mist in the bearing box 10 from entering the interior of the motor through an additional sealing unit in the bearing box 10, and prevent it from adhering to the motor rotor and stator coil, thereby preventing the motor coil temperature from rising and the core and coil end insulation from corroding. The sealing unit is a horizontal center-split structure, which is convenient for maintenance and adjustment in daily maintenance and inspection. There is no need to disassemble the motor rotor, and only the bearing box 10 on the motor needs to be disassembled, which reduces the maintenance workload and maintenance time. The setting of the filter 80 ensures the cleanliness of the air entering the bearing box 10 and the motor box, prolongs the motor operation cycle, and is more suitable for safe and long-term operation of the motor in harsh environments.

[0078] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

[0079] In the description herein, many specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of the specific details or with other devices, systems, components, methods, components, materials, parts, etc. In other cases, well-known structures, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0080] References throughout this specification to "one embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention, and not necessarily in all embodiments. Thus, various appearances of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout this specification do not necessarily refer to the same embodiment. In addition, the particular features, structures, or characteristics of any specific embodiment of the invention may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the invention described and illustrated herein may be possible in light of the teachings herein and are to be considered part of the spirit and scope of the invention.

[0081] It should also be understood that one or more of the elements shown in the figures may also be implemented in a more separate or more integrated manner, or even removed because they are inoperable in certain circumstances or provided because they may be useful depending on the application.

[0082] In addition, unless otherwise explicitly indicated, any marking arrows in the drawings should be regarded as exemplary only and not limiting. In addition, unless otherwise indicated, the term "or" used herein is generally intended to mean "and / or". In the case where the term is not clear because it is anticipated that the ability to separate or combine is provided, the combination of components or steps will also be regarded as indicated.

[0083] As used in the description herein and throughout the claims that follow, "a," "an," and "the" include plural references unless otherwise indicated. Likewise, as used in the description herein and throughout the claims that follow, the meaning of "in" includes "in" and "on," unless otherwise indicated.

[0084] The above description of the illustrated embodiments of the present invention (including the contents described in the Abstract) is not intended to be an exhaustive list or to limit the present invention to the precise form disclosed herein. Although specific embodiments of the present invention and examples of the present invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention as will be recognized and appreciated by those skilled in the art. As noted, these modifications may be made to the present invention in accordance with the above description of the embodiments described in the present invention, and these modifications will be within the spirit and scope of the present invention.

[0085] Systems and methods have been generally described herein as details that aid in understanding the present invention. In addition, various specific details have been given to provide an overall understanding of embodiments of the present invention. However, those skilled in the relevant art will recognize that embodiments of the present invention may be practiced without one or more of the specific details, or may be practiced using other devices, systems, accessories, methods, components, materials, parts, etc. In other cases, well-known structures, materials, and / or operations are not specifically shown or described in detail to avoid confusion with various aspects of embodiments of the present invention.

[0086] Thus, although the invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the foregoing disclosure, and it should be understood that in some cases, some features of the invention will be employed without the corresponding use of other features without departing from the scope and spirit of the proposed invention. Thus, many modifications may be made to adapt a particular environment or material to the essential scope and spirit of the invention. The invention is not intended to be limited to the specific terms used in the claims below and / or the specific embodiments disclosed as the best mode contemplated for carrying out the invention, but the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Thus, the scope of the invention will be determined solely by the appended claims.

Claims

1. A sealing structure, characterized in that: Applied to a rotating part, the rotating part includes a rotor and a bearing box, the rotating shaft of the rotor is rotatably matched with the bearing in the bearing box, and the sealing structure includes: a first annular seal, arranged coaxially with the rotating shaft, the first annular seal being located at a side of the bearing housing close to the rotor, and the first annular seal being used to form a seal between the bearing housing and the rotating shaft; a second annular seal, arranged coaxially with the rotating shaft, the second annular seal being located on a side of the first annular seal close to the rotor, and the second annular seal being used to form a seal between the bearing housing and the rotating shaft; an isolation chamber, located between the first annular seal and the second annular seal, the isolation chamber covers the axial direction of the rotating shaft, and the isolation chamber is communicated with the atmosphere; A sealing unit is disposed between the isolation chamber and the first annular seal, and the sealing unit is used to form a seal between the bearing box and the rotating shaft.

2. The sealing structure according to claim 1, characterized in that: The sealing unit comprises a spiral sealing component, which is arranged on the rotating shaft and rotates with the rotating shaft. The rotating direction of the spiral sealing component with the rotating shaft is to prevent the internal material of the bearing box from leaking into the isolation chamber.

3. The sealing structure according to claim 2, characterized in that: The sealing unit further comprises an annular sealing seat, the inner wall of which is sealingly matched with the outer periphery of the spiral sealing assembly.

4. The sealing structure according to claim 3, characterized in that: An end surface of the spiral sealing component close to the isolation chamber is flush with an end surface of the annular sealing seat close to the isolation chamber.

5. The sealing structure according to claim 3, characterized in that: The bearing box is provided with a mounting surface for axial mounting of the annular seal seat, and an end surface of one side of the spiral seal assembly close to the first annular seal is axially spaced from the mounting surface.

6. The sealing structure according to claim 5, characterized in that: The axial distance between the spiral seal assembly and the mounting surface is 1.2-1.5 times the axial leakage of the rotor.

7. The sealing structure according to claim 2, characterized in that: The spiral seal assembly comprises: A spiral seal body, composed of two identical annular halves, the spiral seal body being provided with radial screws for pressing against the rotating shaft; A pressure plate, composed of two identical annular halves, the pressure plates being mounted on both end surfaces of the spiral seal body respectively; Wherein, the boundary of the annular half of the pressure plate and the boundary of the annular half of the spiral sealing body are offset by 90 degrees in the circumferential direction.

8. The sealing structure according to claim 7, characterized in that: The spiral seal body is provided with an annular mounting groove for flush embedding of the pressing plate. The outer diameter of the pressing plate is smaller than the outer diameter of the spiral seal body, and the inner diameter of the pressing plate is larger than the inner diameter of the spiral seal body.

9. The sealing structure according to claim 1, characterized in that: The bearing box is provided with an air path for connecting the isolation chamber and the atmosphere, and a filter is detachably connected to one end of the air path close to the atmosphere, and an air filter element is arranged in the filter.

10. The sealing structure according to claim 1, characterized in that: The first annular seal and the second annular seal are both floating labyrinth seals arranged on the bearing housing.

Images