Spiral sealing element for main bearing of wind driven generator

Abstract

The utility model belongs to the technical field of shaft sealing, in particular to a spiral sealing element for a main bearing of a wind driven generator, which is characterized in that a dustproof sealing lip and a sealing spiral lip are arranged on the inner ring surface of a sealing head and have the same inner diameter; the dustproof sealing lip is a closed full-circle lip and located on the side, close to the atmosphere side, of the inner ring face, the sealing spiral lips are spirally distributed along the inner ring face of the sealing head, and a long and narrow oil seal channel is formed between the spiral lips. According to the utility model, the long and narrow grease channel is formed by the multiple spiral sealing lips, so that the grease is subjected to labyrinth sealing in a static state, and the grease overflowing into the labyrinth is pumped back into the bearing by utilizing the rotating motion of the rotating shaft in a working state; the sealing dustproof lip is a closed full-circle lip, dust on the atmosphere side can be effectively prevented from entering the sealing lip, meanwhile, grease leaked from the grease channel can be blocked, and therefore the effects of buffering the grease and preventing the grease from entering the atmosphere side can be achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of shaft sealing, in particular to a spiral sealing element used for a main bearing of a wind turbine generator. Background Art

[0002] Wind power generation is an environmentally friendly renewable energy source and one of the world's important clean energy sources. It is being widely promoted and used by countries around the world as an important clean energy source. Seals need to be installed on both sides of the main bearings of wind turbines. The design life of a wind turbine is generally 20 years. As a core component, the seal has a design life of no less than 10 years. The function of the seal is to prevent the leakage of lubricating grease in the bearing and prevent dust particles in the atmosphere from entering the bearing. Due to the large diameter of the shaft and the large radial runout of the bearing, the grease in the bearing will continue to leak to the atmosphere when using traditional rotating seals.

[0003] At present, the main bearing seals of wind turbines mostly use traditional annular rubber lip seals, and a small number use mechanical labyrinth seals. However, these two have one thing in common: continuous grease leakage.

[0004] Grease leakage has always been a problem that has troubled wind turbine manufacturers and wind farm operation and maintenance departments. Operation and maintenance personnel are required to clean up the leaked grease regularly, which brings huge workload and even safety hazards. Summary of the invention

[0005] The utility model aims to provide a spiral seal for a main bearing of a wind turbine generator, so as to solve the problem raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a spiral seal for a main bearing of a wind turbine, characterized in that it includes an outer sealing shoulder and an inner sealing head, wherein the inner ring surface of the sealing head is provided with a dustproof sealing lip and a sealing spiral lip, and the inner diameters of the two are the same; the dustproof sealing lip is a closed full-circle lip, located on the side of the inner ring surface close to the atmosphere, the sealing spiral lips are distributed in a spiral along the inner ring surface of the sealing head, and a narrow and long oil seal channel is formed between the spiral lips.

[0007] In the above technical scheme, the sealing spiral lip is an open spiral type, and a narrow grease channel is formed by using spiral multiple sealing lips to realize a labyrinth seal for the grease under static conditions. Under working conditions, the rotational motion of the rotating shaft is used to pump the grease overflowing into the labyrinth back into the bearing; the sealing dustproof lip is a closed full-circle lip, which can effectively prevent dust on the atmospheric side from entering the sealing lip and even entering the bearing, and can also block the grease leaking from the grease channel, so that the blocked grease can be pumped back into the grease channel when the rotating shaft is working, thereby caching the grease and preventing the grease from entering the atmospheric side.

[0008] As a preferred solution, the number of spiral turns of the sealing spiral lip is at least two, ensuring a good labyrinth sealing effect for grease in a static state.

[0009] As a preferred solution, the sealing spiral lip has a lip starting end and a lip ending end, and the end faces of the two are inclined and transitionally connected with the inner annular surface. The inclined end face can be less in contact with the rotating shaft, reducing its deformation after assembly, preventing the grease channel from being blocked due to excessive deformation, and ensuring that the grease flows smoothly in the grease channel.

[0010] As a preferred solution, the seal has a connection end I and a connection end II, both of which have a splicing surface I and a splicing surface II facing each other, and a splicing interface is set in the middle of the splicing surface I, and a splicing joint is set in the middle of the splicing surface II, and the splicing joint is plugged into the splicing interface. For non-initial assembly processes, this splicing structure can remove the seal from the seal installation groove and replace it without disassembling too many parts, effectively reducing the difficulty of maintenance, improving maintenance efficiency, and significantly reducing maintenance costs.

[0011] As a preferred solution, the splicing interface runs through the entire thickness of the seal, and its opening width shrinks in the part close to the splicing surface I. The shape of the splicing joint is completely matched with the splicing interface. This splicing structure is not easy to break and has a larger contact surface. After the seal installation groove is compressed, the connection end I and the connection end II of the entire seal are held together without any gap, thereby ensuring a good installation state.

[0012] As a preferred solution, the annular surface of the sealing shoulder on the grease side is the contact surface I, and an annular protrusion is provided cocentrically with the contact surface I, which can provide an excellent static sealing effect in the assembled state.

[0013] As a preferred solution, a coaxial annular deformation groove is opened at the connection between the sealing shoulder and the sealing head, and a sealing neck with a thickness less than that of the sealing head is formed. The sealing neck with this structure enables the seal to have sufficient elasticity when subjected to radial force, thereby satisfying the radial elastic compensation of the seal.

[0014] As a preferred solution, the annular surface of the sealing shoulder located on the atmosphere side is the splicing surface II, and an annular step is provided between the splicing surface II and the side surface of the deformation groove.

[0015] As a preferred solution, the edges on the sealing shoulder adjacent to the outer circumferential surface are chamfered and formed. The chamfer not only facilitates the installation of the entire seal, but also prevents the weak right-angle edges from being damaged during installation, thereby reducing the sealing performance of the sealing ring and shortening the service life of the sealing ring.

[0016] The utility model has the following beneficial effects:

[0017] 1. The sealing spiral lip of the spiral seal of the present application is spiral-shaped, forming a narrow and long oil seal channel, which can significantly increase the overflow distance of the grease. During operation, the pumping effect of the spiral oil seal channel and the rotation of the rotor on the grease will continuously pump the grease entering the maze back to the grease chamber, thereby achieving a leak-free sealing effect for large-diameter rotating mechanisms;

[0018] 2. The spiral seal of the present application adopts a turning forming production process. Compared with other production processes, the sealing size is more accurate and larger seals can be produced;

[0019] 3. The spiral seal of the present application can withstand 4 bar of grease pressure, can meet a maximum rotational linear speed of 3 m / s, and can meet all wind power application conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 A schematic cross-sectional structure diagram of a spiral seal for a main bearing of a wind turbine provided by the utility model;

[0022] Figure 2 A schematic plan view of the structure of a spiral seal for a main bearing of a wind turbine provided by the utility model;

[0023] Figure 3 for Figure 2 A schematic diagram of the three-dimensional structure of the spiral seal shown;

[0024] Figure 4 for Figure 2 A schematic plan view of a partial section of the spiral seal;

[0025] Figure 5 for Figure 4A schematic diagram of the three-dimensional structure of a partial segment spiral seal is shown;

[0026] Figure 6 for Figure 2 Schematic diagram of the split structure of the middle connection end I and the connection end II;

[0027] Figure 7 It is a cross-sectional structural diagram of the seal installation position of the main bearing of a wind turbine;

[0028] Figure 8 for Figure 2 The diagram shows the deformation state of the spiral seal in the assembled state.

[0029] In the figure, sealing shoulder 1, sealing head 2, deformation groove 3, neck 4, contact surface I5, annular protrusion 6, contact surface II7, step 8, dustproof sealing lip 9, sealing spiral lip 10, chamfer 11, connecting end I12, connecting end II13, sealing support 20, pressure plate 21, rotating shaft 22, seal mounting groove 23, grease side contact surface 24, circumferential contact surface 25, atmosphere side contact surface 26, sliding sealing surface 27, splicing surface I121, splicing interface 122, splicing surface II131, splicing joint 132, lip starting end 101, and lip ending end 102. DETAILED DESCRIPTION

[0030] The following will describe the implementation methods of the present application in detail with the help of accompanying drawings and examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0031] Figure 1-3 As an embodiment of the utility model, a spiral seal for the main bearing of a wind turbine generator is produced by a turning process. The whole is made of hydrolysis-resistant polyurethane material (TDI or MDI) and has excellent wear resistance and weather resistance. The spiral seal includes a sealing shoulder 1, a sealing neck 4 and a sealing head 2 from the outer ring to the inner ring, wherein the sealing neck 4 belongs to the connection structure between the sealing shoulder 1 and the sealing head 2, which is formed by setting a trapezoidal annular deformation groove 3 on the surface of the connection structure, so the thickness of the sealing neck 4 is smaller than the thickness of the sealing head 2 and the sealing shoulder 1. It is precisely because the sealing neck 4 has the above characteristics that the seal has sufficient elasticity when subjected to radial force, thereby meeting the radial elastic compensation requirements of the seal.

[0032] The inner ring surface of the sealing head 2 is provided with a dustproof sealing lip 9 and a sealing spiral lip 10, and the inner diameters of the two are the same. The dustproof sealing lip 9 is a closed full-circle lip located on the side of the inner ring surface close to the atmosphere; the sealing spiral lip 10 is an open lip, which is spirally distributed along the inner ring surface of the sealing head 2 for more than two circles, and a narrow and long oil seal channel is formed between the spiral lips, and from Figure 4 and Figure 5 It can be seen that the sealing spiral lip 10 has a lip starting end 101 and a lip ending end 102, and the end faces of both are beveled and transitionally connected with the inner annular surface. The inclined end faces at both ends of the sealing spiral lip 10 can be less in contact with the rotating shaft 22, thereby preventing the lip starting end 101 and the lip ending end 102 from affecting the circulation of grease due to excessive deformation.

[0033] In addition, Figure 1 In the embodiment, the annular surface of the sealing shoulder 1 located on the grease side is set as the contact surface I5, and the annular surface located on the atmosphere side is set as the splicing surface II 7. Two circles of concentric annular protrusions 6 are set on the contact surface I5, and an annular step 8 is set between the splicing surface II7 and the side of the deformation groove 3. In order to facilitate installation and prevent the sealing shoulder 1 from being damaged during installation and use, the edge of the sealing shoulder 1 adjacent to the outer circumferential surface is configured as a 45° chamfer 11 in this embodiment. The chamfer 11 not only facilitates the installation of the entire seal, but also prevents the weak right-angle edge from being damaged during installation, thereby reducing the sealing performance of the sealing ring and shortening the service life of the sealing ring.

[0034] The spiral seal disclosed in this embodiment is generally suitable for rotary sealing conditions with a diameter of 300mm-10000mm. The equipment is troublesome to disassemble and assemble. In order to facilitate the production and disassembly of the seal, the seal of this embodiment adopts the form of end-to-end splicing. Figure 2 and Figure 4 It can be seen that the spiral seal is spliced ​​into a ring by connecting end I12 and connecting end II13, that is, the entire spiral seal is in a strip shape in the open state. Figure 6 As shown, the connection end I12 and the connection end II13 respectively have a splicing surface I121 and a splicing surface II131 that are facing each other, and a splicing interface 122 is set in the middle of the splicing surface I121. The splicing interface 122 runs through the entire thickness of the seal, and its opening width shrinks in the part close to the splicing surface I121, and the overall shape is similar to an "Ω" shape; a splicing joint 132 is set in the middle of the splicing surface II131. Since the connection end I12 and the connection end II13 are cut by the same tool, the shape of the splicing joint 132 is completely matched with the splicing interface 122.

[0035] The spiral seal provided in this embodiment is applied to the main bearing of a wind turbine generator, such as Figure 7As shown, its installation environment includes a sealing support 20 and a pressure plate 21 arranged around a rotating shaft 22, wherein the pressure plate 21 is located on the atmosphere side and is installed on the sealing support 20 by bolts, and a sealing installation groove 23 with an opening facing the rotating shaft 22 is formed between the pressure plate 21 and the sealing support 20. In order to facilitate the description and understanding of the usage and working principle of the spiral seal, the installation environment is marked as follows: the side of the sealing installation groove 23 close to the atmosphere is marked as the atmosphere side contact surface 26, the side close to the grease side is marked as the grease side contact surface 24, the circumferential surface facing the rotating shaft 22 is the circumferential contact surface 25, and the circumferential surface of the rotating shaft 22 is the sliding sealing surface 27.

[0036] Regarding the assembly of the seal, it should be noted first that the sealing spiral lip 11 can rotate clockwise or counterclockwise, and its usage principle is that when the rotating shaft 23 is working, the rotation direction of the sealing spiral lip 10 of the spiral seal is opposite to the rotation direction of the rotating shaft 23, so that the medium (grease) sealed in the oil seal channel moves along the spiral oil seal channel under the action of the pumping effect, and is continuously "introduced" to the grease side, achieving a "zero leakage" sealing effect.

[0037] In order to ensure the above-mentioned sealing effect, the size of the spiral seal disclosed in this embodiment has the following characteristics. First, the outer diameter dimension φd of the spiral seal is larger than the bottom diameter φD of the seal installation groove 23 (the diameter of the circle where the circumferential contact surface 25 is located). The two are interference fit. After the seal is installed, the seal is in a radial compression state. Secondly, the radial dimension t of the cross section of the spiral seal is larger than the radial dimension T of the seal installation groove 23 (the radial distance between the circumferential contact surface 25 and the sliding sealing surface 27). After the seal is installed, the dustproof sealing lip 10 and the sealing spiral lip 11 have a reasonable amount of compression deformation, and as Figure 8 As shown, both are deformed toward the grease side and fit the sliding sealing surface 27, so that the dustproof sealing lip 9 and the sealing spiral lip 10 are effectively in contact with the sliding sealing surface 27 of the rotating shaft 22. The above-mentioned dimensional characteristics of the spiral seal not only realize the static sealing between the outer circumferential surface of the seal and the circumferential contact surface 25 of the seal installation groove 23, but also realize that the seal is subjected to pressure in the circumferential direction instead of tension, so the dustproof sealing lip 9 and the sealing spiral lip 10 are pressed on the sliding sealing surface 27, and the sealing lip is more fatigue-resistant.

[0038] In addition, the axial height dimension h of the sealing shoulder 13 of the spiral seal disclosed in this embodiment is greater than the axial height dimension H of the mounting groove 23 (the axial distance between the grease side contact surface 24 and the atmosphere side contact surface 26), and Figure 8It can be seen that by tightening the bolts, the two circles of annular protrusions 6 set on the contact surface I5 are squeezed and deformed and tightly fit the grease side contact surface 24, and the axial compression of the entire sealing shoulder 13 is about 0.5 mm, so the seal is firmly fixed, and the set annular protrusion 6 can provide an excellent static sealing effect.

[0039] The sealing principle of the spiral seal disclosed in this patent relies on the narrow and long labyrinth channel (i.e., oil seal channel) formed by the spiral sealing spiral lip 11, and the pumping effect of the grease produced by the rotation of the shaft. The grease entering the labyrinth channel is continuously pumped back to the grease chamber, thereby achieving a leakage-free sealing effect for large-diameter rotating mechanisms.

[0040] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect.

[0041] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0042] The above description shows and describes several preferred embodiments of the utility model, but as mentioned above, it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. A spiral seal for a main bearing of a wind turbine generator, characterized in that: It comprises an outer sealing shoulder (1) and an inner sealing head, wherein the inner ring surface of the sealing head is provided with a dustproof sealing lip and a sealing spiral lip, and the inner diameters of the two are the same; the dustproof sealing lip is a closed full-circle lip, located on the side of the inner ring surface close to the atmosphere, and the sealing spiral lip is distributed in a spiral along the inner ring surface of the sealing head, and a narrow and long oil seal channel is formed between the spiral lips.

2. A spiral seal for a main bearing of a wind turbine generator according to claim 1, characterized in that: The number of spiral turns of the sealing spiral lip is at least two.

3. A spiral seal for a main bearing of a wind turbine generator according to claim 1, characterized in that: The sealing spiral lip has a lip starting end and a lip ending end, and the end faces of the two are inclined and transitionally connected with the inner annular surface.

4. A spiral seal for a main bearing of a wind turbine generator according to claim 1, characterized in that: The sealing component has a connecting end I and a connecting end II, both of which respectively have a splicing surface I and a splicing surface II facing each other, and a splicing interface is arranged in the middle of the splicing surface I, and a splicing joint is arranged in the middle of the splicing surface II, and the splicing joint is plugged into and matched with the splicing interface.

5. A spiral seal for a main bearing of a wind turbine generator as claimed in claim 4, characterized in that: The joint surface runs through the entire thickness of the seal, and its opening width shrinks in the part close to the joint surface I; the shape of the joint head is completely matched with the joint surface.

6. A spiral seal for a main bearing of a wind turbine generator according to claim 1, characterized in that: The annular surface of the sealing shoulder located on the grease side is the contact surface I, and an annular protrusion is arranged cocentrically with the contact surface I.

7. A spiral seal for a main bearing of a wind turbine generator according to any one of claims 1 to 6, characterized in that: A coaxial annular deformation groove is provided at the connection between the sealing shoulder and the sealing head, and a sealing neck with a thickness smaller than that of the sealing head is formed.

8. A spiral seal for a main bearing of a wind turbine generator according to claim 7, characterized in that: The annular surface of the sealing shoulder located on the atmosphere side is the contact surface II, and an annular step is arranged between the contact surface II and the side surface of the deformation groove.

9. A spiral seal for a main bearing of a wind turbine generator according to any one of claims 1 to 6, characterized in that: The edge of the sealing shoulder adjacent to the outer circumferential surface is chamfered and formed.

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