Sealing structure for solving oil leakage at oil seal of speed reducer
By introducing a sealing structure consisting of an end cover, an oil baffle, and an oil slinger ring into the reducer, the problem of lubricating oil leakage at the oil seal is solved, achieving effective utilization of lubricating oil and sealing effect, and preventing bearing lubricating oil leakage and the intrusion of external contaminants.
Patent Information
- Application Number
- CN202610045480.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-14
- Publication Date
- 2026-03-06
AI Technical Summary
Existing gearboxes often experience oil leaks due to grooves formed at the oil seal contact point caused by friction between the shaft and the oil seal, as well as the accumulation of lubricating oil leading to excessive steam pressure.
A sealing structure including an end cover, an oil baffle, an oil slinger ring, and an oil seal is designed. By setting an oil inlet groove and an oil return groove on the end cover, the oil slinger ring throws the lubricating oil into the large cavity and returns it to the housing through the oil return hole. Combined with the oil baffle and the annular gasket, the axial clearance is adjusted to prevent lubricating oil leakage.
It effectively prevents lubricating oil from accumulating at the oil seal, reduces oil leakage, ensures the supply of lubricating oil to meet the lubrication and cooling needs of the bearing, and reduces the intrusion of external contaminants.
Smart Images
Figure CN121611751A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of speed reducer technology, specifically a sealing structure for solving oil leakage at the oil seal of a speed reducer. Background Technology
[0002] As a key sealing element in mechanical equipment, the core function of an oil seal is to prevent lubricating oil from leaking from the shaft end, while also blocking external contaminants such as dust and moisture from entering the system, thereby ensuring the normal lubrication and long-term stable operation of transmission components such as bearings and gears.
[0003] However, in practical applications, oil seal systems often fail to seal due to various factors. For example, grooves may form at the contact point between the shaft and the oil seal due to prolonged friction, creating an oil leakage channel; the accumulation of lubricating oil at this point may lead to excessive steam pressure, exacerbating the tendency of the oil seal lip to open, and so on, resulting in oil leakage. Summary of the Invention
[0004] The purpose of this invention is to provide a sealing structure for solving oil leakage at the oil seal of a speed reducer. The speed reducer includes a speed reducer housing, a shaft, and a bearing. The speed reducer housing has a shaft hole, one end of the shaft passes through the shaft hole, and a bearing is fitted onto the shaft. The sealing structure includes an end cover, an oil baffle plate, an oil slinger ring, and an oil seal.
[0005] Both the oil baffle and the oil slinger ring are sleeved on the shaft and rotate synchronously with it. The oil slinger ring has a ring-shaped structure with multiple annular grooves on its outer wall. The oil baffle is a rotating structure located between the oil slinger ring and the bearing, and has an annular flange on the side closest to the oil slinger ring.
[0006] An end cover is installed at the shaft hole. The end cover is fixed to the reducer housing. The end cover has a rotating structure.
[0007] An oil seal chamber is provided on the side of the end cover facing away from the gearbox. The oil seal is located in the oil seal chamber, and the inner ring of the oil seal is in close contact with the oil slinger ring.
[0008] The inner wall of the end cap is provided with two small grooves and one large groove spaced apart. The large groove is located between the two small grooves. In the assembled state, the small grooves and the large groove, together with the outer wall of the oil slinger ring, form a small cavity and a large cavity, respectively, and the annular groove on the oil slinger ring is located in the large cavity.
[0009] The reducer housing has multiple oil inlet holes and oil return holes spaced around the shaft hole. The end cover has multiple oil inlet grooves and oil return grooves spaced apart. The positions of the oil inlet grooves and oil return grooves correspond one-to-one with the positions of the oil inlet holes and oil outlet holes of the reducer housing.
[0010] The end cover is provided with an oil return hole, which is connected to the large cavity and the inside of the reducer housing.
[0011] Furthermore, an annular gasket is provided between the end cap and the bearing, and the oil baffle is located in the inner ring of the gasket.
[0012] Furthermore, the annular flange on the oil baffle plate has a frustum-shaped structure, with the inclined surface of the frustum facing the bearing side.
[0013] Furthermore, the reducer housing has one housing oil inlet and two housing oil return holes. The three oil holes are spaced apart, with adjacent oil holes spaced 120° apart.
[0014] Furthermore, during operation, some oil accumulates in the annular groove of the oil slinger ring. When the oil slinger ring rotates synchronously with the shaft, the oil accumulated in the annular groove will be thrown into the large cavity, and the oil in the large cavity will return to the gearbox through the oil return hole on the end cover.
[0015] Furthermore, the oil-slinging ring is provided with two annular grooves.
[0016] Furthermore, the oil baffle plate and the shaft are interference fit.
[0017] The oil slinger ring and the shaft are interference fit.
[0018] Furthermore, the oil slinger ring and the end cap are fitted with a clearance.
[0019] Furthermore, the gap between the oil slinger ring and the end cap is 0.2–0.3 mm.
[0020] Furthermore, the reducer housing has multiple connecting bolt holes spaced around the shaft hole. The end cover has multiple threaded connecting holes spaced apart. The threaded connecting holes correspond one-to-one with the connecting bolt holes, and bolts pass through the threaded connecting holes and connecting bolt holes in sequence to assemble the end cover onto the reducer housing.
[0021] The technical effects of this invention are undeniable, and its beneficial effects are as follows:
[0022] 1. The reducer housing of the present invention has an oil inlet hole and an oil return hole, and the end cover has an oil inlet groove and an oil return groove. The two correspond to each other. The structure can ensure the lubricating oil required for bearing lubrication and cooling, and prevent the lubricating oil from accumulating here and thus generating large steam pressure.
[0023] 2. This invention incorporates an oil slinger ring between the end cover and the shaft. This effectively prevents grooves from forming due to friction between the shaft and the oil seal, and also allows the lubricating oil adhering to the ring to be thrown back into the large cavity of the end cover and back into the housing. Simultaneously, two small cavities are formed, which can further trap some of the lubricating oil, reducing the amount of lubricating oil entering the housing. Attached Figure Description
[0024] Figure 1This is a schematic diagram of a sealing structure for solving oil leakage at the oil seal of a speed reducer according to the present invention;
[0025] Figure 2 for Figure 1 A magnified view of a portion of the image;
[0026] Figure 3 This is a schematic diagram of the mounting surface of the reducer end cover;
[0027] Figure 4 Figure 1 is a schematic diagram of the end cap, where Figure (a) is the front view of the end cap and Figure (b) is the sectional view of section AA in Figure (a).
[0028] In the diagram: 1. Gearbox housing, 101. Shaft hole, 2. Shaft, 3. End cover, 301. Small cavity, 302. Oil baffle, 4. Annular flange, 401. Oil slinger ring, 5. Annular groove, 501. Oil seal, 6. Bearing, 7. Oil inlet hole, 8. Oil return hole, 9. Connecting bolt hole, 10. Oil inlet groove, 11. Oil return groove, 12. Threaded connection hole, 13. Oil return hole, 15. Gasket, 16. Detailed Implementation
[0029] The present invention will be further described below with reference to embodiments, but it should not be construed that the scope of the present invention is limited to the following embodiments. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention should be included within the scope of protection of the present invention.
[0030] Example 1:
[0031] A sealing structure for solving oil leakage at the oil seal of a speed reducer is disclosed. The speed reducer includes a speed reducer housing 1, a shaft 2, and a bearing 7. The speed reducer housing 1 has a shaft hole 101, one end of the shaft 2 passes through the shaft hole 101, and the bearing 7 is sleeved on the shaft 2. The sealing structure includes an end cover 3, an oil baffle 4, an oil slinger ring 5, and an oil seal 6.
[0032] The oil baffle plate 4 and the oil slinger ring 5 are both sleeved on the shaft 2 and rotate synchronously with the shaft 2. The oil slinger ring 5 has a ring-shaped structure with multiple annular grooves 501 on its outer wall surface. The oil baffle plate 4 has a rotating structure, located between the oil slinger ring 5 and the bearing 7, and has an annular flange 401 on the side closer to the oil slinger ring 5.
[0033] An end cover 3 is installed at the shaft hole 101. The end cover 3 is fixed to the reducer housing 1. The end cover 3 is a rotating structure.
[0034] An oil seal chamber is provided on the side of the end cover 3 facing away from the reducer housing 1. The oil seal 6 is located in the oil seal chamber, and the inner ring of the oil seal 6 is in close contact with the oil slinger ring 5.
[0035] The inner wall of the end cap 3 is provided with two small grooves and one large groove at intervals. The large groove is located between the two small grooves. In the assembled state, the small groove and the large groove, together with the outer wall of the oil slinger ring 5, form a small cavity 301 and a large cavity 302, respectively, and the annular groove 501 on the oil slinger ring 5 is located in the large cavity 302.
[0036] The reducer housing 1 is provided with a plurality of housing oil inlet holes 8 and housing oil return holes 9 at intervals around the shaft hole 101. The end cover 3 is provided with a plurality of oil inlet grooves 11 and oil return grooves 12 at intervals. The positions of the oil inlet grooves 11 and oil return grooves 12 correspond one-to-one with the positions of the housing oil inlet holes 8 and housing oil outlet holes 9.
[0037] The end cap 3 is provided with an oil return hole 15, which is connected to the large cavity 302 and the inside of the reducer housing 1.
[0038] Example 2:
[0039] The main structure of this embodiment is the same as that of Embodiment 1. Furthermore, an annular gasket 16 is provided between the end cap 3 and the bearing 7 to adjust the axial clearance of the bearing. The oil baffle 4 is located within the inner ring of the gasket 16.
[0040] Example 3:
[0041] The main structure of this embodiment is the same as any one of embodiments 1 to 2. Furthermore, the annular flange 401 on the oil baffle 4 is a frustum-shaped structure, with the inclined surface of the frustum facing the bearing 7.
[0042] Example 4:
[0043] The main structure of this embodiment is the same as any one of embodiments 1 to 3. Furthermore, the reducer housing 1 is provided with a housing oil inlet 8 and two housing oil return holes 9. The three oil holes are spaced apart, with an interval of 120° between adjacent oil holes.
[0044] Example 5:
[0045] The main structure of this embodiment is the same as any one of embodiments 1 to 4. Furthermore, during operation, some oil accumulates in the annular groove 501 of the oil slinger ring 5. When the oil slinger ring 5 rotates synchronously with the shaft 2, the oil accumulated in the annular groove 501 will be thrown towards the large cavity 302. The oil in the large cavity 302 will then return to the reducer housing 1 through the oil return hole 15 on the end cover 3.
[0046] Example 6:
[0047] The main structure of this embodiment is the same as any one of embodiments 1 to 5. Furthermore, the oil slinger ring 5 is provided with two annular grooves 501.
[0048] Example 7:
[0049] The main structure of this embodiment is the same as any one of embodiments 1 to 6. Furthermore, the oil baffle 4 and the shaft 2 are interference fit.
[0050] The oil slinger ring 5 and the shaft 2 are interference fit.
[0051] Example 8:
[0052] The main structure of this embodiment is the same as any one of embodiments 1 to 7. Furthermore, the oil slinger ring 5 and the end cap are in clearance fit.
[0053] Example 9:
[0054] The main structure of this embodiment is the same as any one of embodiments 1 to 8. Furthermore, the gap between the oil slinger ring 5 and the end cap is 0.2 to 0.3 mm.
[0055] Example 10:
[0056] The main structure of this embodiment is the same as any one of embodiments 1 to 9. Furthermore, in this embodiment, the gap between the oil slinger ring 5 and the end cap is 0.2 mm.
[0057] Example 11:
[0058] The main structure of this embodiment is the same as any one of embodiments 1 to 9. Furthermore, in this embodiment, the gap between the oil slinger ring 5 and the end cap is 0.3 mm.
[0059] Example 12:
[0060] The main structure of this embodiment is the same as any one of embodiments 1 to 9. Furthermore, in this embodiment, the gap between the oil slinger ring 5 and the end cap is 0.25 mm.
[0061] Example 13:
[0062] The main structure of this embodiment is the same as any one of embodiments 1 to 12. Furthermore, the reducer housing 1 is provided with a plurality of connecting bolt holes 10 spaced around the shaft hole 101. The end cover 3 is provided with a plurality of threaded connecting holes 13 spaced apart. The threaded connecting holes 13 correspond one-to-one with the connecting bolt holes 10. Bolts pass through the threaded connecting holes 13 and the connecting bolt holes 10 in sequence to assemble the end cover 3 onto the reducer housing 1.
[0063] Example 14:
[0064] The main structure of this embodiment is the same as any one of embodiments 1 to 13. Furthermore, the reducer housing 1 has an oil inlet and an oil return hole (see...). Figure 3 The end cap 3 has an oil inlet groove and an oil return groove (see...). Figure 4The two correspond to each other. This structure can ensure the lubricating oil required for bearing lubrication and cooling, while preventing the lubricating oil from accumulating here and generating large vapor pressure.
[0065] An oil baffle plate 4, an oil slinger ring 5, and an oil seal 6 are fitted onto shaft 2. The oil baffle plate 4 and the oil slinger ring 5 are interference-fitted onto shaft 2 and rotate together with shaft 2 (see [link]). Figure 1 , Figure 2 ).
[0066] The inclined surface of the oil baffle plate 4 faces the bearing to prevent lubricating oil from splashing violently onto the oil seal.
[0067] Only a small installation space of about 0.25mm is left between the oil slinger ring 5 and the end cap 3, allowing only a small amount of lubricating oil to enter. At the same time, the oil slinger ring 5 has two grooves that can throw the lubricating oil adhering to it into the large cavity 302 of the end cap (see...). Figure 2 Then, through the return oil hole 15 inside the end cap 3 (see...) Figure 4 ), and return to the box body. Meanwhile, two small cavities 301 are left on the end cap 3 (see...). Figure 2 This can intercept some of the lubricating oil, reducing the amount of lubricating oil entering the system.
[0068] An oil seal 6 is installed on the outermost side to seal off any very small amount of lubricating oil that may pass through.
Claims
1. A sealing structure for solving the oil leakage at the oil seal of a speed reducer, the speed reducer comprising a speed reducer housing (1), a shaft (2) and a bearing (7); the speed reducer housing (1) is provided with a shaft hole (101), one end of the shaft (2) passes through the shaft hole (101), and the bearing (7) is sleeved on the shaft (2), characterized in that: The sealing structure comprises an end cover (3), an oil baffle (4), a flinger (5) and an oil seal (6); The oil baffle (4) and the flinger (5) are sleeved on the shaft (2) and rotate synchronously with the shaft (2); the flinger (5) is in a ring structure and is provided with a plurality of annular grooves (501) on the outer wall surface; the oil baffle (4) is in a rotary body structure, is located between the flinger (5) and the bearing (7) and is provided with an annular flange (401) on the side close to the flinger (5); The end cover (3) is fixed on the reducer box (1); the end cover (3) is in a rotary body structure. An oil seal chamber is arranged on the side end face of the end cover (3) away from the reducer box (1); the oil seal (6) is arranged in the oil seal chamber and the inner ring of the oil seal (6) is tightly attached to the flinger (5); Two small grooves and one large groove are arranged on the inner wall surface of the end cover (3) at intervals; the large groove is located between the two small grooves; in the assembled state, the small grooves and the large groove enclose a small cavity (301) and a large cavity (302) with the outer wall of the flinger (5) respectively; the annular grooves (501) arranged on the flinger (5) are located in the large cavity (302). A plurality of box oil inlet holes (8) and box oil return holes (9) are arranged on the reducer box (1) at intervals around the shaft hole (101); a plurality of oil inlet grooves (11) and oil return grooves (12) are arranged on the end cover (3) at intervals; the positions of the oil inlet grooves (11) and the oil return grooves (12) correspond to the positions of the box oil inlet holes (8) and the box oil outlet holes (9) one by one. An oil return hole (15) is arranged on the end cover (3) and the oil return hole (15) is in communication with the large cavity (302) and the inside of the reducer box (1) respectively.
2. The seal structure for solving the oil leakage at the oil seal of a speed reducer according to claim 1, characterized in that: The annular flange (401) on the oil baffle (4) is in a circular truncated cone structure and the inclined surface of the circular truncated cone faces the side of the bearing (7).
3. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The reducer box (1) is provided with one box oil inlet hole (8) and two box oil return holes (9); the three oil holes are arranged at intervals and the adjacent oil holes are spaced apart by 120°.
4. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: When working, part of the oil accumulates in the annular grooves (501) of the flinger (5); when the flinger (5) rotates synchronously with the shaft (2), the oil accumulated in the annular grooves (501) is thrown to the large cavity (302) and the oil in the large cavity (302) returns to the reducer (1) box through the oil return hole (15) on the end cover (3).
5. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The flinger (5) is provided with two annular grooves (501).
6. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The oil baffle (4) and the shaft (2) are in interference fit; 7. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The flinger (5) and the shaft (2) are in interference fit. The flinger (5) and the end cover are in clearance fit.
8. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The clearance between the flinger (5) and the end cover is 0.2-0.3 mm.
9. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 8, characterized in that: 10. The seal structure for solving the oil leakage of the oil seal of the speed reducer according to claim 1, characterized in that: The multiple connecting bolt holes (10) are arranged on the reducer box (1) around the shaft hole (101); the multiple threaded connecting holes (13) are arranged on the end cover (3) at intervals; the threaded connecting holes (13) and the connecting bolt holes (10) correspond to each other, the bolts pass through the threaded connecting holes (13) and the connecting bolt holes (10) in sequence, and the end cover (3) is assembled on the reducer box (1).