A composite seal for tapered roller main bearing of wind turbine

Abstract

The present application relates to a composite seal for a tapered roller main bearing of a wind turbine, belonging to the field of wind power generation, and comprising a bearing body, wherein the bearing body comprises a bearing inner ring and a bearing outer ring, wherein two groups of tapered rollers are arranged between the bearing inner ring and the bearing outer ring, wherein the ends of the two groups of tapered rollers close to each other form a lubrication cavity for containing lubricating oil, wherein the ends of the tapered rollers away from each other form a grease cavity, wherein a guide oil cavity connected to the grease cavity is formed between the bearing inner ring and the bearing outer ring, wherein the guide oil cavity is connected to a grease outlet hole, wherein a guide member and a seal member are arranged on the bearing inner ring or the bearing outer ring, wherein the guide member is located in the guide oil cavity, and wherein the seal member is used to seal the end of the guide oil cavity away from the grease cavity. The present application has the function of improving the sealing effect of the tapered roller main bearing of a wind turbine.

Description

Technical Field

[0001] The present application relates to the field of wind power generation, and in particular to a composite seal for a tapered roller main bearing of a wind turbine. Background Art

[0002] As the megawatt and impeller diameter of wind turbines increase, tapered roller bearings are increasingly used as main bearings for wind turbines. Tapered roller bearings include an inner ring and an outer ring. When used in wind turbines, the typical layout is that the inner ring and outer ring of the bearing are connected to the stationary conical support or the rotating generator respectively. In order to lubricate the bearing rollers and reduce friction, a lubrication cavity is formed between the inner ring and the outer ring of the bearing. When the rollers rotate, they can contact the grease in the lubrication cavity to play a lubricating role. However, during the operation of the shaft, due to the pumping effect of the tapered rollers, the grease will be sucked out of the lubrication cavity, resulting in grease leakage, which is not conducive to maintenance and there is a risk of fire. In addition, after a lot of grease leakage, the bearing will lack grease inside, and the bearing life will be sharply shortened.

[0003] The existing method of reducing grease leakage is: a cloth-inserted oil seal is provided at the end cover of the bearing to reduce grease leakage; and a grease outlet hole is provided on the inner ring of the bearing to guide the grease sucked out by the roller pump through the grease outlet hole for centralized recovery and treatment.

[0004] The inventor believes that the grease outlet hole is limited by the main shaft structure, and the path of the grease outlet hole is relatively circuitous, so that the grease often needs to flow out through a complex and long path, with greater resistance, and it is difficult to grease out of the long grease outlet hole. After a long time, the grease will accumulate and emulsify, dry up and cause blockage, making the grease cavity more and more grease, which will cause the grease pressure in the grease cavity to continue to increase. When the pressure accumulates to a certain level and generates pressure, the grease will leak from the cloth oil seal, and the sealing effect is poor. Summary of the invention

[0005] In order to improve the sealing effect of a tapered roller main bearing of a wind turbine generator set, the present application provides a composite seal for a tapered roller main bearing of a wind turbine generator set.

[0006] The composite seal of the tapered roller main bearing of a wind turbine provided in this application adopts the following technical solution:

[0007] A composite seal for a tapered roller main bearing of a wind turbine generator system comprises a bearing body, wherein the bearing body comprises a bearing inner ring and a bearing outer ring, two groups of tapered rollers are arranged between the bearing inner ring and the bearing outer ring, a lubrication cavity for accommodating lubricating oil is formed at one end of the two groups of tapered rollers that are close to each other, a grease cavity is formed at one end of the tapered rollers that are away from each other, a guide oil cavity connected to the grease cavity is formed between the bearing inner ring and the bearing outer ring, the guide oil cavity is connected to a grease outlet hole, a guide member and a sealing member are arranged on the bearing inner ring or the bearing outer ring, the guide member is located in the guide oil cavity, the sealing member is used to close the end of the guide oil cavity that is away from the grease cavity, and when the bearing inner ring rotates forwardly relative to the bearing outer ring, the guide member rotates to cause the grease in the guide oil cavity to flow from a side close to the sealing member to a side close to the grease outlet hole.

[0008] By adopting the above technical scheme, during use, the grease in the lubrication chamber can lubricate the bearing roller, and the tapered roller will pump the grease in the lubrication chamber into the grease chamber during rotation. At the same time, the guide member will rotate with the inner ring of the bearing or the outer ring of the bearing, thereby generating a reverse thrust to make the grease in the guide oil chamber flow from the side close to the seal to the side close to the grease outlet hole, thereby reducing the pressure on the seal to improve the reliability of the seal; the grease is squeezed into the grease outlet hole under the pumping action of the tapered roller and the joint action of the guide member, so that the grease can overcome the flow resistance and be smoothly discharged, and the grease will not accumulate in the grease outlet hole for a long time, so it is not easy to emulsify and dry up, thereby ensuring the smooth flow of the grease outlet hole.

[0009] Optionally, the guide member includes a positioning ring and a plurality of blades distributed circumferentially along the positioning ring, and the blades are spiral-shaped.

[0010] By adopting the above technical solution, the positioning ring can drive the blade to rotate when rotating, and the spiral shape of the blade can generate axial thrust to push the grease in the guide oil cavity from the side close to the seal to the side close to the grease outlet hole.

[0011] Optionally, the guide member is a helical gear.

[0012] By adopting the above technical solution, the gear has better rigidity, does not deform during operation, and has better stability.

[0013] Optionally, an external gear is provided on the bearing body, the external gear is meshed with the guide member, and the external gear is located at a position where the grease outlet hole is connected to the guide oil chamber.

[0014] By adopting the above technical solution, when the bearing body is running, the meshing of the outer gear and the guide member can drive the outer gear to rotate. On the one hand, suction is generated to make the grease at the seal flow to the outer gear, and at the same time, the grease in the grease chamber is sucked to the outer gear through the guide oil chamber; on the other hand, thrust is generated to make the grease be discharged from the grease outlet hole, which can generate greater thrust and better grease discharge effect.

[0015] Optionally, the seal includes a support ring, which is provided with a static lip and a plurality of dynamic lips, the static lip is located on the side of the dynamic lip away from the guide oil chamber, and a sealing bevel for abutting the dynamic lip and the static lip is formed on the bearing body, and the distance between the sealing bevel and the support ring gradually decreases from the side away from the grease outlet hole to the side close to the grease outlet hole.

[0016] By adopting the above technical solution, when the bearing rotates, the suction force generated by the rotation of the external gear and the guide member first causes the lowermost lip of the movable lip to move toward the grease chamber, and the interference between the lip and the sealing bevel gradually increases, and the sealing ability gradually increases. With long-term operation, the lowermost lip of the movable lip gradually wears, and at this time, the other movable lip on its upper side is subject to increased suction and gradually moves downward, which can make up for the sealing ability lost by the lower sealing ring.

[0017] Optionally, a first extension portion is provided at one end of the movable lip away from the support ring, and the first extension portion is inclined in a direction away from the grease outlet hole.

[0018] By adopting the above technical solution, when the movable lip moves downward under the action of suction, the contact area between the first extension portion and the sealing inclined surface is increased, and the sealing effect is better.

[0019] Optionally, a second extension portion is provided at one end of the static lip away from the support ring, and the second extension portion is inclined toward a direction approaching the grease outlet hole.

[0020] By adopting the above technical solution, the second extension portion can prevent external water, dust and salt mist from entering.

[0021] Optionally, the cross-sectional area of ​​the guide oil chamber gradually increases from an end close to the grease chamber to an end close to the grease outlet hole.

[0022] By adopting the above technical solution, when the grease flows, the pressure at the end of the oil guide chamber close to the grease chamber is higher, and the pressure at the end close to the grease outlet hole is lower, so that the grease can flow more smoothly from the grease chamber to the grease outlet hole.

[0023] Optionally, a pressure plate is provided on the bearing body, and the pressure plate is fixedly connected to the bearing body by bolts, and the pressure plate applies pressure to the seal and the guide member to keep the seal and the guide member fixed.

[0024] By adopting the above technical solution, the pressure plate can keep the seal and the guide member stable. At the same time, when the seal is severely worn, the seal can be directly inserted after removing the pressure plate, which makes maintenance more convenient.

[0025] In summary, the present application includes at least one of the following beneficial technical effects:

[0026] The bearing is rotated to drive the guide to suck the grease from the seal, which reduces the grease pressure on the seal, reduces the requirements for the seal, and increases the sealing reliability;

[0027] The new combined multi-lip seal ring structure is used to eliminate the spring in the existing seal, which has lower cost, better sealing and longer service life;

[0028] Combined with fluid dynamics, a guide oil chamber is used to utilize the suction of the guide piece and the roller pump to generate thrust to push the grease out of the grease hole, thus avoiding the risk of long-term grease accumulation in the grease chamber causing sealing ring leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of the three-dimensional structure of Example 1 of the present application;

[0030] Figure 2 is a schematic cross-sectional structure diagram of Example 1;

[0031] Figure 3 yes Figure 2 A is a partial enlarged schematic diagram;

[0032] Figure 4 is a schematic structural diagram of the guide member in Example 2;

[0033] Figure 5 It is a schematic diagram of the cross-sectional structure of Example 3 of the present application.

[0034] Explanation of the reference numerals: 1. bearing inner ring; 2. bearing outer ring; 3. tapered roller; 4. lubrication chamber; 5. grease chamber; 6. guide oil chamber; 7. seal; 71. support ring; 72. moving lip; 73. stationary lip; 74. first extension; 75. second extension; 8. guide; 9. grease outlet hole; 10. sealing bevel; 11. pressure plate; 12. blade; 13. positioning ring; 14. external gear. DETAILED DESCRIPTION

[0035] The following is combined with Figure 1-5 This application is described in further detail.

[0036] Embodiment 1, this application embodiment discloses a composite seal for the main bearing of a tapered roller 3 of a wind turbine. Figure 1 and Figure 2A composite seal for a tapered roller 3 main bearing of a wind turbine includes a bearing body, the bearing body includes a bearing inner ring 1 and a bearing outer ring 2, the bearing inner ring 1 is connected to a conical support in the wind turbine, and the bearing outer ring 2 is connected to a generator. In another embodiment, the bearing inner ring 1 may be connected to the generator, and the bearing outer ring 2 may be connected to a conical support in the wind turbine.

[0037] In the specific application of fan bearings, two sets of single-row tapered roller bearings or double-row tapered roller bearings can be used. For double-row tapered roller bearings, two sets of tapered rollers 3 are arranged between the bearing inner ring 1 and the bearing outer ring 2. When the bearing inner ring 1 rotates relative to the bearing outer ring 2, the tapered rollers 3 rotate.

[0038] A lubrication cavity 4 for containing grease is formed in the bearing body at one end where the two groups of tapered rollers 3 are close to each other. During the rotation process, the tapered rollers 3 will contact the grease in the lubrication cavity 4, so that the tapered rollers 3 are lubricated and the wear during operation is reduced. A grease cavity 5 is formed at one end where the tapered rollers 3 are far away from each other. Due to the conical shape of the tapered rollers 3, during the rotation process of the tapered rollers 3, the end where the two tapered rollers 3 are far away from each other has a larger diameter and a larger surface linear velocity, while the end where the tapered rollers 3 are close to each other has a smaller diameter and a smaller surface linear velocity. According to the Bernoulli principle, a pressure difference will be generated at both ends of the tapered rollers 3, so that the grease in the lubrication cavity 4 will be pumped into the grease cavity 5.

[0039] The bearing inner ring 1 is provided with a grease outlet hole 9, and a guide oil chamber 6 is provided between the grease outlet hole 9 and the grease chamber 5. When the grease in the grease chamber 5 is full, the grease will enter the grease outlet hole 9 through the guide oil chamber 6, and then be collected and processed. A seal 7 is provided between the bearing outer ring 2 and the bearing inner ring 1. The seal 7 is used to close the end of the guide oil chamber 6 away from the grease chamber 5, so that the grease is not easy to seep out from the gap between the bearing inner ring 1 and the bearing outer ring 2.

[0040] Reference Figure 2 , a guide member 8 is also provided on the bearing outer ring 2. When the bearing inner ring 1 rotates forward relative to the bearing outer ring 2, the guide member 8 rotates to make the grease in the guide oil chamber 6 flow from the side close to the seal 7 to the side close to the grease outlet 9. In this embodiment, the guide member 8 is a helical gear, which is coaxially arranged with the bearing outer ring 2 and fixed on the bearing outer ring 2. The tooth portion of the helical gear is located in the guide oil chamber 6. When the helical gear rotates forward synchronously with the bearing outer ring 2, an axial suction force is generated, thereby pushing the oil at the position of the seal 7 to the position of the grease outlet 9. At the same time, the pumping force generated by the rotation of the tapered roller 3 will also make the grease in the grease chamber 5 flow toward the guide gear through the guide oil chamber 6. Under the guidance of the guide oil chamber 6, the grease will be pushed to the grease outlet 9 and flow out.

[0041] The guide 8 is misaligned with the grease outlet 9, so that the grease outlet 9 is located between the guide 8 and the grease cavity 5, so that the grease enters the grease hole under the joint action of the guide 8 and the tapered roller 3. The guide 8 can be made of rubber material or engineering plastics such as polyethylene.

[0042] Reference Figure 3 The seal 7 includes a support ring 71 and a dynamic lip 72 and a static lip 73 arranged on the support ring 71. The support ring 71 is sleeved on the bearing outer ring 2. The dynamic lip 72 and the static lip 73 are both annular and arranged on the inner side of the support ring 71. The static lip 73 is located on the side of the dynamic lip 72 away from the guide oil chamber 6.

[0043] The movable lip 72 is provided in two groups in an axially stacked manner, and may be provided in more groups in other embodiments. A sealing bevel 10 for the movable lip 72 and the stationary lip 73 is formed on the bearing body, and the distance between the sealing bevel 10 and the support ring 71 gradually decreases from the side away from the grease outlet 9 to the side close to the grease outlet 9. A first extension portion 74 is provided at one end of the movable lip 72 away from the support ring 71, and the first extension portion 74 is inclined in a direction away from the grease outlet 9. Under the action of the suction force generated by the guide member 8, the movable lip 72 closest to the guide oil chamber 6 will move toward the grease chamber 5, and the interference between the lip of the movable lip 72 and the inner ring 1 of the bearing will gradually increase, and the sealing ability will gradually increase. With long-term operation, the lowermost lip of the movable lip 72 gradually wears, and at this time, the other movable lip 72 on its upper side is subject to the increased suction force and gradually moves downward, making up for the sealing ability lost by the lower sealing ring.

[0044] The second extension part 75 is arranged at one end of the static lip 73 away from the support ring 71, and the second extension part 75 is inclined toward the direction close to the grease outlet 9 to prevent the entry of external water, dust and salt spray. When the fan is stationary or even rotates in the reverse direction accidentally, the grease can pass through the dynamic lip 72, but will be blocked by the static lip 73, and then stored between the static lip 73 and the dynamic lip 72, ensuring that the static lip 73 and the dynamic lip 72 will not wear out quickly due to long-term lack of grease lubrication, thereby extending the sealing life.

[0045] The cross-sectional area of ​​the guide oil chamber 6 gradually increases from one end close to the grease chamber 5 to one end close to the grease outlet hole 9, so that the grease can flow more smoothly from the grease chamber 5 to the grease outlet hole 9 and is not easy to flow in the opposite direction.

[0046] A pressure plate 11 is provided on the outer ring 2 of the bearing. The pressure plate 11 is fixedly connected to the bearing body by bolts. The pressure plate 11 is pressed tightly against the seal 7 and the guide 8 to keep the seal 7 and the guide 8 fixed during operation, which can improve stability. When the seal 7 is severely worn, the seal 7 can be directly inserted after the pressure plate 11 is removed, which is convenient for maintenance.

[0047] The implementation principle of the composite seal of the tapered roller main bearing 3 of a wind turbine set in the embodiment of the present application is: by setting a guide member 8, combining fluid dynamics, using a guide oil chamber 6, and utilizing the suction of the guide member 8 and the suction of the roller pump to generate thrust to push the grease out of the grease hole, which is beneficial to the discharge of grease from the bearing grease hole 9 and reduces the risk of grease leakage.

[0048] Example 2, reference Figure 4 The difference between this embodiment and embodiment 1 is that the guide member 8 includes a positioning ring 13 and a plurality of blades 12 distributed circumferentially along the positioning ring 13. The blades 12 are spirally shaped and fixed to the inner side of the positioning ring 13. The positioning ring 13 is fixed to the outer ring 2 of the bearing. When the positioning ring 13 rotates with the outer ring 2 of the bearing, it can drive the blades 12 to rotate, thereby driving the grease to flow. Furthermore, the blades 12 and the positioning ring 13 are detachably connected. When the blades 12 are worn, the blades 12 can be removed and replaced separately, which is convenient to use.

[0049] Example 3, reference Figure 5 The difference between this embodiment and embodiment 1 is that an external gear 14 is rotatably connected to the inner ring 1 of the bearing, and multiple external gears 14 are evenly spaced along the circumference of the inner ring 1 of the bearing. The external gear 14 is meshed with the helical gear, and the external gear 14 is located at the position where the grease outlet hole 9 is connected to the guide oil chamber 6.

[0050] When the helical gear rotates synchronously with the bearing outer ring 2, it will drive the outer gear 14 to rotate through meshing. Due to the large number of teeth, the outer gear 14 will rotate at high speed, which will generate suction on the one hand to make the grease at the seal 7 flow to the outer gear 14, and also suck the grease in the grease chamber 5 to the outer gear 14 through the guide oil chamber 6; on the other hand, it will generate thrust to make the grease be discharged from the grease outlet 9. The grease pressure at the seal ring is reduced, the requirements for the seal ring are reduced, and the sealing reliability is increased. At the same time, the suction of the guide 8 and the suction of the tapered roller 3 pump generate thrust to push the grease out of the grease hole, avoiding the risk of grease accumulation in the grease chamber 5 for a long time and causing leakage of the seal ring.

[0051] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A composite seal for a tapered roller main bearing of a wind turbine generator set, characterized in that: The invention comprises a bearing body, wherein the bearing body comprises a bearing inner ring (1) and a bearing outer ring (2), two groups of tapered rollers (3) are arranged between the bearing inner ring (1) and the bearing outer ring (2), a lubrication cavity (4) for containing lubricating oil is formed at one end of the two groups of tapered rollers (3) close to each other, a grease cavity (5) is formed at one end of the tapered rollers (3) away from each other, and a guide hole (5) connected to the grease cavity (5) is formed between the bearing inner ring (1) and the bearing outer ring (2). The guide oil chamber (6) is connected to a grease outlet hole (9). A guide member (8) and a sealing member (7) are provided on the bearing inner ring (1) or the bearing outer ring (2). The guide member (8) is located in the guide oil chamber (6). The sealing member (7) is used to seal the end of the guide oil chamber (6) away from the grease chamber (5). When the bearing inner ring (1) rotates in the positive direction relative to the bearing outer ring (2), the guide member (8) rotates to make the guide oil chamber (6) The grease flows from the side close to the sealing element (7) to the side close to the grease outlet hole (9); the sealing element (7) comprises a support ring (71), the support ring (71) is provided with a stationary lip (73) and a movable lip (72), the stationary lip (73) is located on the side of the movable lip (72) away from the guide oil chamber (6), the bearing body is formed with a sealing bevel (10) for abutting against the movable lip (72) and the stationary lip (73), the sealing bevel (10) and the support ring (71) are connected to each other. 1) gradually decreases from the side away from the grease outlet hole (9) to the side close to the grease outlet hole (9); the end of the movable lip (72) away from the support ring (71) is provided with a first extension portion (74), the first extension portion (74) is inclined in a direction away from the grease outlet hole (9); the end of the stationary lip (73) away from the support ring (71) is provided with a second extension portion (75), the second extension portion (75) is inclined in a direction close to the grease outlet hole (9).

2. A composite seal for a tapered roller main bearing of a wind turbine according to claim 1, characterized in that: The guide member (8) comprises a positioning ring (13) and a plurality of blades (12) distributed along the circumference of the positioning ring (13).

3. The composite seal for tapered roller main bearing of a wind turbine according to claim 1, characterized in that: The guide member (8) is a helical gear.

4. A composite seal for a tapered roller main bearing of a wind turbine according to claim 3, characterized in that: An external gear (14) is provided on the bearing body, the external gear (14) is meshed with the guide member (8), and the external gear (14) is located at a position where the grease outlet hole (9) is connected to the guide oil chamber (6).

5. The composite seal for tapered roller main bearing of a wind turbine according to claim 1, characterized in that: The cross-sectional area of ​​the guide oil chamber (6) gradually increases from an end close to the grease chamber (5) to an end close to the grease outlet hole (9).

6. The composite seal for tapered roller main bearing of a wind turbine according to claim 1, characterized in that: A pressure plate (11) is provided on the bearing body, and the pressure plate (11) is fixedly connected to the bearing body via bolts. The pressure plate (11) applies pressure to the seal (7) and the guide (8) to keep the seal (7) and the guide (8) fixed.

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