Medium-speed gear box output shaft sealing oil return structure

Abstract

The utility model relates to the technical field of gearboxes, in particular to a sealing oil return structure for an output shaft of a medium-speed gearbox, which comprises a rear box body, an output bearing seat, an output shaft end cover, a pressing plate, a front output bearing, a rear output bearing and an output shaft which are axially connected in sequence, wherein the front output bearing, the rear output bearing and the output shaft are mounted in the output shaft end cover; a left output shaft seal and a right output shaft seal are radially arranged on the output shaft; a first clearance seal is radially assembled between the left output shaft seal and the output shaft, and a second clearance seal is radially assembled between the right output shaft seal and the output shaft end cover; a first oil return channel is arranged in the output bearing seat, a second oil return channel is formed between the output bearing seat and the left output shaft seal, and a third oil return channel is formed between the output bearing seat and the output shaft end cover; according to the scheme, the problem that an oil return structure in an existing medium-speed gear box is insufficient in reliability can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of gearboxes, and particularly relates to an output shaft sealing and oil return structure of a medium-speed gearbox. Background Technique

[0002] The gearbox in a wind turbine is a crucial mechanical component, and its main function is to convert the low-speed rotational motion generated by the wind turbine under the action of wind into high-speed rotational motion to meet the rotational speed required for the generator to generate electricity. The design and manufacture of the gearbox need to consider the long-term stable operation of the wind power generation unit in various harsh environments, including mountain passes, wilderness, beaches, islands and other windy areas. Therefore, the reliability and service life requirements of the gearbox are much higher than those of general machinery, and sufficient lubrication conditions need to be ensured.

[0003] At present, most of the gearboxes operating in wind farms are medium-speed gearboxes, whose rotational speed is between that of low-speed and high-speed gearboxes. The characteristic is that the oil return channels inside it are set singly, resulting in the mutual mixing and accumulation of some lubricating oil, which easily causes the phenomenon of unsmooth oil return. For example, an output shaft sealing mechanism of a wind power gearbox (publication number: CN208793584U) disclosed in the prior art, in order to solve the problem of lubricating oil or oil-gas mixture flowing into the nacelle and tower barrel and causing pollution, a unified oil recovery mechanism is set on the lower sealing mechanism. Although the oil can be recovered and reused, the unified oil return channel cannot meet the high requirements of wind power generation for the reliability of the gearbox. After being used for a long time, the problem of mutual mixing and accumulation of lubricating oil in various places greatly increases the probability of oil leakage at the gap seal of the output shaft. Content of the Utility Model

[0004] The utility model provides an output shaft sealing and oil return structure of a medium-speed gearbox, which can solve the problem of insufficient reliability of the existing oil return structure in the medium-speed gearbox.

[0005] The present application provides the following technical solutions:

[0006] An output shaft sealing and oil return structure of a medium-speed gearbox, characterized in that: it includes a rear box body, an output bearing seat, an output shaft end cover, and a pressing plate that are axially connected in sequence, a front output bearing, a rear output bearing, and an output shaft installed in the output shaft end cover, a guiding shaft axially arranged in the output shaft, a left output shaft seal and a right output shaft seal radially arranged on the output shaft; a first clearance seal is radially assembled between the left output shaft seal and the output shaft, and a second clearance seal is radially assembled between the right output shaft seal and the output shaft end cover; a first oil return channel is arranged in the output bearing seat, a second oil return channel is formed between the output bearing seat and the left output shaft seal, and a third oil return channel is formed between the output bearing seat and the output shaft end cover.

[0007] Beneficial effects: By separately arranging the first oil return channel, the second oil return channel, and the third oil return channel at different positions, the lubricating oil flowing out from different parts can be separately recovered, avoiding the problem of mutual mixing and accumulation caused by sharing an oil return channel, enabling the lubricating oil to be smoothly recovered, greatly reducing the oil leakage problem in the output shaft sealing structure of the medium-speed gearbox, and greatly enhancing the overall reliability of the sealed oil return structure. On this basis, the first clearance seal and the second clearance seal are provided to enhance the overall sealing ability of the sealed oil return structure, and fundamentally reduce the probability of lubricating oil leakage.

[0008] Further, as an improvement, both the first clearance seal and the second clearance seal are composed of multiple radial clearance seals, and the multiple radial clearance seals are arranged in a layered and staggered manner.

[0009] Beneficial effects: Multiple radially staggered clearance seals form multiple sealing barriers. Even if one clearance leaks, other clearances can continue to prevent fluid leakage, thereby improving the overall sealing effect. The intersecting and staggered radial clearances contribute to fluid circulation, can promote heat dissipation, help maintain a stable temperature in the sealed area, avoid material aging or deformation caused by overheating, and improve the overall durability of the sealing structure.

[0010] Further, as an improvement, a fourth oil return channel is provided on the right side of the pressing plate, and an elbow pipe communicating with each other is provided below the fourth oil return channel.

[0011] Beneficial effects: The fourth oil return channel provided on the pressing plate is the last barrier to prevent lubricating oil leakage in this structure. Even if a small amount of leaked oil appears, it can ensure that it flows back to the medium-speed gearbox through the elbow pipe.

[0012] Further, as an improvement, both the second oil return channel and the fourth oil return channel are composed of multiple interconnected channels.

[0013] Beneficial effects: Designing the oil return channel in segments to adapt to the overall shape design of the gearbox not only helps optimize the structural compactness, but also the reasonable segmentation and channel layout can help the lubricating oil to be more evenly distributed and flow, enhancing the overall reliability of the oil return structure. Description of the Drawings

[0014] Figure 1 It is a cross-sectional view of the first embodiment of the output shaft sealed oil return structure of a medium-speed gearbox of the present invention;

[0015] Figure 2 is different from Figure 1 the cross-sectional view shown;

[0016] Figure 3 is Figure 1 the enlarged schematic view at E in Detailed implementation manners

[0017] The following is a further detailed description through specific implementation manners:

[0018] The markings in the attached drawings of the specification include: rear housing 1, output bearing seat 2, front output bearing 3, rear output bearing 4, output shaft 5, guiding shaft 6, left output shaft seal 7, output shaft end cover 8, right output shaft seal 9, pressing plate 10, elbow pipe 11, first oil return passage 101, oil return passage one 201, oil return passage two 202, oil return passage three 301, oil return passage four 302, oil return passage five 303, oil return passage six 304, oil return passage seven 305, fourth oil return passage 401, radial clearance seal one 1-1, radial clearance seal two 1-2, radial clearance seal three 1-3, radial clearance seal four 2-1, radial clearance seal five 2-2, radial clearance seal six 2-3, radial clearance seal seven 3-1, radial clearance seal eight 3-2, radial clearance seal nine 3-3, radial clearance seal ten 3-4, radial clearance seal eleven 3-5.

[0019] Embodiment 1

[0020] As Figures 1 - 3 shown, a middle-speed gearbox output shaft seal oil return structure includes a rear housing 1, an output bearing seat 2, an output shaft end cover 8, and a pressing plate 10 that are axially connected in sequence, a front output bearing 3, a rear output bearing 4, and an output shaft 5 installed in the output shaft end cover 8, a guiding shaft 6 axially arranged in the output shaft 5, a left output shaft seal 7 and a right output shaft seal 9 radially arranged on the output shaft 5, and the output shaft end cover 8 abuts against the pressing plate 10.

[0021] A first oil return passage 101 is arranged in the output bearing seat 2, a second oil return passage is formed between the output bearing seat 2 and the left output shaft seal 7, and the second oil return passage includes an oil return passage one 201 and an oil return passage two 202. A third oil return passage is formed between the output bearing seat 2 and the output shaft end cover 8, and the third oil return passage includes an oil return passage three 301, an oil return passage four 302, an oil return passage five 303, an oil return passage six 304, and an oil return passage seven 305. A fourth oil return passage 401 is arranged on the right side of the pressing plate 10, and an elbow pipe 11 that is interconnected is arranged below the fourth oil return passage 401.

[0022] A plurality of sections of first clearance seals are radially assembled between the left output shaft seal 7 and the output shaft 5. In this embodiment, the first clearance seals include as Figure 2The radial clearance seals 1-1, 1-2, and 1-3 located to the left of the left output shaft seal 7 are arranged in a staggered and layered manner between the radial clearance seals 1-1, 1-2, and 1-3. Similarly, the first clearance seal also includes the radial clearance seals 2-1, 2-2, and 2-3 located to the right of the left output shaft seal 7, and the radial clearance seals 2-1, 2-2, and 2-3 are also arranged in a staggered and layered manner between them.

[0023] A second clearance seal is radially assembled between the right output shaft seal 9 and the output shaft end cover 8. In this embodiment, the second clearance seal includes, as Figure 2 shown, the radial clearance seals 3-1, 3-2, 3-3, 3-4, and 3-5 arranged in sequence from top to bottom. The clearance seals 3-1, 3-2, 3-3, 3-4, and 3-5 are also arranged in a layered and staggered manner.

[0024] The specific application process is as follows:

[0025] During use, the lubricating oil may seep out along three paths. The first path consists of the radial clearance seals 1-1, 1-2, and 1-3 located to the left of the left output shaft seal 7. The second path consists of the radial clearance seals 2-1, 2-2, and 2-3. The third path consists of the radial clearance seals 3-1, 3-2, 3-3, 3-4, and 3-5. Since the seals in each path are composed of multiple staggered clearance seals, the pressure of the lubricating oil during flow in the path is effectively relieved, which not only enhances its sealing effect but also reduces the siphon phenomenon caused by the internal and external pressure difference in the wind power gearbox, preventing the lubricating oil from being directly thrown outwards. A first oil return channel 101, a second oil return channel, and a third oil return channel are separately provided at the ends of the first path, the second path, and the third path respectively, enabling the separately recovered lubricating oil seeping out from different parts to avoid the problem of mutual mixing and accumulation caused by sharing an oil return channel, ensuring the smooth recovery of the lubricating oil, and greatly reducing the oil leakage problem in the output shaft seal structure of the medium-speed gearbox.

[0026] The above are only embodiments of the present utility model. The present utility model is not limited to the fields involved in this embodiment case. Common knowledge such as specific structures and characteristics known in the solution is not described in detail herein. It should be noted that for those skilled in the art, without departing from the structure of the present utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the present utility model, and these will not affect the implementation effect of the present utility model and the practicality of the patent. The protection scope claimed in this application shall be subject to the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.

Claims

1. A medium-speed gearbox output shaft seal oil return structure, characterized in that: It includes a rear box body, an output bearing seat, an output shaft end cover, and a pressure plate which are axially connected in sequence, a front output bearing, a rear output bearing, and an output shaft installed in the output shaft end cover, a guide shaft is axially arranged in the output shaft, and a left output shaft seal and a right output shaft seal are radially arranged on the output shaft; a first gap seal is radially assembled between the left output shaft seal and the output shaft, and a second gap seal is radially assembled between the right output shaft seal and the output shaft end cover; a first oil return passage is arranged in the output bearing seat, a second oil return passage is formed between the output bearing seat and the left output shaft seal, and a third oil return passage is formed between the output bearing seat and the output shaft end cover.

2. A medium speed gearbox output shaft seal oil return structure according to claim 1, characterized in that: The first gap seal and the second gap seal are both composed of a plurality of radial gap seals, and the plurality of radial gap seals are arranged in layers and staggered.

3. A medium speed gearbox output shaft seal oil return structure according to claim 2, characterized in that: A fourth oil return passage is arranged on the right side of the pressure plate, and mutually communicating bent pipes are arranged below the fourth oil return passage.

4. The medium speed gearbox output shaft seal oil return structure according to claim 3, characterized in that: The second oil return passage and the fourth oil return passage are both composed of a plurality of channels interconnected with each other.

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