Sealing device of speed reducer and speed reducer

Abstract

The utility model provides a sealing device of a speed reducer and the speed reducer, and particularly relates to the field of speed reducers. The speed reducer comprises a box body and a transmission shaft, and the box body is rotationally connected with the transmission shaft. The sealing device comprises a shaft sleeve, a sealing ring and an end cover. The shaft sleeve is sleeved on the transmission shaft, and the shaft sleeve is fixedly connected with the transmission shaft; the shaft sleeve is sleeved with the sealing ring, and the sealing ring is fixedly connected with the shaft sleeve; the end cover is fixedly mounted on the box body and is opposite to the sealing ring; wherein the sealing ring and the end cover form a labyrinth sealing structure, a first contact sealing structure is arranged between the sealing ring and the end cover, and a second contact sealing structure is arranged between the end cover and the shaft sleeve. According to the sealing device, labyrinth sealing and contact sealing are combined, so that the sealing effect of the speed reducer is effectively improved, and the speed reducer meets the operation requirements of no leakage and long service life of the speed reducer under the large-load and high-speed working conditions.

Description

Technical Field

[0001] The utility model relates to the field of reducers, in particular to a sealing device of a reducer and a reducer. Background Art

[0002] The reducer is a transmission device used to reduce the speed and increase the torque to meet the work needs. The reducer includes a housing and a transmission shaft. The transmission shaft is rotatably inserted in the housing. In order to maintain good lubrication of the transmission shaft, there must be a good seal between the transmission shaft and the housing to prevent the lubricating oil from leaking from the gap between the transmission shaft and the housing. Most of the existing sealing structures have a single structure and poor sealing effect, which cannot meet the requirements of leak-free and long-life operation of reducers under heavy load and high-speed conditions. Utility Model Content

[0003] In view of the above shortcomings of the prior art, the utility model provides a sealing device for a reducer and a reducer to improve the poor sealing effect of the sealing device, which cannot meet the requirements of leak-free and long-life operation of the reducer under heavy load and high-speed conditions.

[0004] In order to achieve the above-mentioned purpose and other related purposes, the utility model provides a sealing device for a reducer, the sealing device comprising a sleeve, a sealing ring and an end cover. The sleeve is sleeved on the transmission shaft, and the sleeve is fixedly connected to the transmission shaft; the sealing ring is sleeved on the sleeve, and the sealing ring is fixedly connected to the sleeve; the end cover is fixedly installed on the box body and arranged opposite to the sealing ring; wherein the sealing ring and the end cover form a labyrinth sealing structure, a first contact sealing structure is arranged between the sealing ring and the end cover, and a second contact sealing structure is arranged between the end cover and the sleeve.

[0005] In an example of the present invention, along the radial direction of the transmission shaft, the distance between the sealing ring and the end cover is H1, 0.25mm≤H≤1mm.

[0006] In an example of the present invention, along the radial direction of the transmission shaft, a gap between the end cover and the shaft sleeve is H2, 0.25 mm ≤ H2 ≤ 1 mm.

[0007] In an example of the present invention, along the axial direction of the transmission shaft, the spacing between the sealing ring and the end cover is S, and 0.5 mm ≤ S ≤ 2 mm.

[0008] In an example of the present invention, a through hole is provided on the sealing ring, and an angle between a central axis of the through hole and a central axis of the sealing ring is α, 0<α<90°.

[0009] In an example of the present invention, along the axial direction of the through hole, the aperture of the through hole gradually increases from an end close to the end cover to an end away from the end cover.

[0010] In one example of the utility model, the housing is rotatably connected to the transmission shaft via a bearing, a boss is provided at one end of the sleeve close to the transmission bearing, the boss is distributed along the circumference of the sleeve, one side of the boss is in contact with the inner ring of the transmission bearing, and the other side of the boss is in contact with the sealing ring.

[0011] In an example of the present invention, the sealing device further includes an oil cup disposed on the transmission shaft, and the oil cup is in communication with the labyrinth sealing structure.

[0012] In an example of the present invention, the first contact sealing structure is a VD-type sealing ring, and the second contact sealing structure is a rotating shaft lip sealing ring.

[0013] The utility model also provides a reducer, which comprises the sealing device of the reducer.

[0014] The utility model provides a sealing device for a reducer, wherein a sealing ring is fixedly connected to a transmission shaft via a shaft sleeve, an end cover is rotatably connected to the transmission shaft, the sealing ring and the end cover form a labyrinth sealing structure, a first contact sealing structure is arranged between the sealing ring and the end cover, and a second contact sealing structure is arranged between the end cover and the shaft sleeve. The combination of the labyrinth seal and the contact seal can effectively improve the sealing effect of the reducer, so that the reducer can meet the requirements of leakage-free and long-life operation of the reducer under large load and high-speed working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a schematic structural diagram of a reducer of the utility model in one embodiment;

[0017] Figure 2 for Figure 1 The schematic diagram of the cross-sectional structure of the reducer after being cut along the AA cutting line;

[0018] Figure 3 for Figure 2 A partial enlarged schematic diagram of the middle A area;

[0019] Figure 4 for Figure 2 A partial enlarged schematic diagram of the middle B area;

[0020] Figure 5 This is a schematic diagram of the structure of the bearing of the reducer in one embodiment of the utility model;

[0021] Figure 6 for Figure 5 A schematic diagram of the cross-sectional structure of the bearing after being cut along the BB cutting line;

[0022] Figure 7 It is a schematic structural diagram of a shaft sleeve of a sealing device of a reducer of the utility model in one embodiment;

[0023] Figure 8 for Figure 7 A schematic diagram of the cross-sectional structure of the sleeve after being cut along the CC cutting line;

[0024] Fig. 9 This is a schematic structural diagram of a sealing ring of a sealing device for a reducer of the utility model in one embodiment;

[0025] Fig.10 for Fig. 9 A schematic diagram of the cross-sectional structure of the sealing ring after being cut along the DD cutting line;

[0026] Fig.11 This is a schematic structural diagram of an end cover of a sealing device for a reducer of the utility model in one embodiment;

[0027] Fig.12 for Fig.11 Schematic diagram of the cross-sectional structure of the end cover after being cut along the EE cutting line.

[0028] Component number description

[0029] 1. Reducer; 10. Sealing device; 100. Bushing; 110. Boss; 200. Sealing ring; 210. Through hole; 300. End cover; 310. Cover body; 320. Mounting part; 330. Baffle; 400. First contact sealing structure; 500. Second contact sealing structure; 600. Oil cup; 20. Transmission shaft; 30. Housing; 40. Bearing; 401. Inner ring; 402. Outer ring; 403. Rolling element. DETAILED DESCRIPTION

[0030] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, 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. It should also be understood that the terms used in the embodiments of the present invention are intended to describe specific implementations, rather than to limit the scope of protection of the present invention.

[0031] It should be noted that the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of description and are not used to limit the scope of implementation of the present utility model. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of the present utility model without substantially changing the technical content.

[0032] See also Figures 1 to 12 The utility model provides a reducer sealing device 10 and a reducer 1. The sealing device 10 effectively improves the sealing effect of the reducer 1 by combining a labyrinth seal and a contact seal.

[0033] See also Figure 1 and Figure 2 The reducer 1 provided by the utility model includes a sealing device 10, a transmission shaft 20, a housing 30 and a bearing 40. The type of reducer 1 is not limited in the present application, especially for reducers used in locations with high requirements for factory environmental hygiene, strict process quality requirements, difficult equipment failure maintenance, and high equipment added value, such as main transmission reducers in steel mill looper locations, rolling mill reducers, coiler reducers, etc. The use of the sealing device 10 can effectively improve the sealing reliability and maintain the reducer 1 for a long time without leakage.

[0034] See also Figure 1 and Figure 2 The housing 30 is a cubic shell structure, such as a cube or a cuboid. The specific structure of the housing 30 is adjusted according to the type and related configuration of the reducer 1. The housing 30 is generally cast from gray cast iron or cast steel, and has sufficient strength and stability. Two opposite side walls of the housing 30 are provided with holes for the transmission shaft 20 to pass through. The housing 30 is provided with a plurality of transmission members, which are installed on the transmission shaft 20 and other shaft systems. The transmission members on the transmission shaft 20 cooperate with the transmission members on other shaft systems in the housing 30 to transmit power.

[0035] See also Figure 2 , Figure 5 and Figure 6The bearing 40 is used to support and fix the transmission shaft 20 to ensure the stability and precision of the transmission shaft 20. Common bearing types include deep groove ball bearings, cylindrical roller bearings, etc. In one embodiment, the bearing 40 includes an inner ring 401, an outer ring 402, and a rolling element 403. The inner ring 401 is fixedly connected to the transmission shaft 20, and the outer ring 402 is fixedly installed in the housing 30. The inner ring 401 and the outer ring 402 are rotatably connected through the rolling element 403, thereby realizing the rotatable connection between the transmission shaft 20 and the housing 30. The sealing device 10 is arranged in the hole of the housing 30, and the sealing device 10 is located between the transmission shaft 20 and the side wall of the housing 30 to prevent the lubricating oil in the housing 30 and the bearing 40 from leaking.

[0036] See also Figure 2 , the sealing device 10 provided in the present application includes a sleeve 100, a sealing ring 200 and an end cover 300. The sleeve 100 is arranged in the hole of the box body 30 for installing the transmission shaft 20, and the sleeve 100 is sleeved on the position where the transmission shaft 20 extends out of the box body 30. The sleeve 100 is fixedly connected to the transmission shaft 20 for supporting and protecting the transmission shaft 20. The present application does not limit the installation method of the sleeve 100, such as interference fit or welding between the sleeve 100 and the transmission shaft 20. For example, the material of the sleeve 100 is 45 steel or 40Cr. Furthermore, the surface of the sleeve 100 is quenched and hard chrome plated, that is, the material is first quenched, and then a thicker chrome plating layer is plated on the surface after quenching. Furthermore, the quenching thickness of the sleeve 100 surface is ≥0.5 mm, the Rockwell hardness (HRC) of the sleeve 100 surface after quenching is above 55, the chrome plating layer thickness is 0.06-0.1 mm, and the Vickers hardness (HV) of the surface hard chrome plating is 900-1000.

[0037] See also Figure 2 , the sealing ring 200 is mounted on the shaft sleeve 100, and the sealing ring 200 is fixedly connected to the shaft sleeve 100. In one embodiment, the sealing ring 200 and the shaft sleeve 100 are interference fit. In other embodiments, the sealing ring 200 and the shaft sleeve 100 may also be fixedly connected in other ways, for example, the sealing ring 200 and the shaft sleeve 100 are fixedly connected by welding. The present application does not limit the material of the sealing ring 200, as long as the strength and surface roughness of the sealing ring 200 meet the use requirements. Exemplarily, the sealing ring 200 is made of Q345 material, the sealing contact surface Ra of the sealing ring 200 is 0.8, and the Ra of other parts of the sealing ring 200 is 3.2.

[0038] See also Figure 2 , Fig.11 and Fig.12, the end cover 300 is fixedly mounted on the box body 30 and arranged opposite to the sealing ring 200. The end cover 300 includes a cover body 310, a mounting portion 320 arranged along the circumference of the cover body 310, and a baffle 330 arranged on the side of the cover body 310 facing the box body 30, and the baffle 330 extends along the axial direction of the cover body 310. The mounting portion 320 is fixedly connected to the cover body 310, and the mounting portion 320 abuts against the outside of the box body 30, the baffle 330 is embedded in the mounting hole of the transmission shaft 20 on the box body 30, and the outer wall of the baffle 330 fits the box body 30. The end cover 300 can be fixedly connected to the box body 30 by any connection method, and the connection method between the end cover 300 and the box body 30 includes but is not limited to welding, riveting or detachable connection. For example, the end cover 300 is fixedly mounted on the box body 30 by bolts. The present application does not limit the material of the end cover 300, as long as the strength and surface roughness of the end cover 300 meet the use requirements. Exemplarily, the end cover 300 is made of Q345 material, the roughness Ra of the sealing contact surface of the end cover 300 is 3.2, and the tolerance of the end cover 300 complies with GB / T1804-f grade.

[0039] See also Figures 2 to 4 and Figures 9 to 12 , a labyrinth seal structure is formed between the sealing ring 200 and the end cover 300, for example, the sealing ring 200 has a labyrinth seal structure, or the end cover 300 has a labyrinth seal structure, or both the sealing ring 200 and the end cover 300 have a labyrinth seal structure. In one embodiment, the sealing ring 200 and the end cover 300 both have a labyrinth seal structure, the labyrinth seal structure of the sealing ring 200 is arranged opposite to the labyrinth seal structure of the end cover 300, and the labyrinth seal structure of the sealing ring 200 and the labyrinth seal structure of the end cover 300 are gap-matched. Exemplarily, a protrusion and a depression are provided on the side of the sealing ring 200 opposite to the end cover 300, and a depression and a protrusion that match the protrusion and depression of the sealing ring 200 are provided on the side of the end cover 300 opposite to the sealing ring 200. The protrusions and depressions on the sealing ring 200 and the end cover 300 slow down the flow of lubricating oil to achieve a sealing effect. Furthermore, a first contact seal structure 400 is provided between the seal ring 200 and the end cover 300, and a second contact seal structure 500 is provided between the end cover 300 and the sleeve 100. The first contact seal structure 400 and the second contact seal structure 500 can not only enhance the sealing effect on the lubricating oil, but also prevent external impurities from entering the reducer 1.

[0040] See also Figure 2 and Figure 3In one embodiment, the first contact sealing structure 400 is a VD-type sealing ring. The structure of the VD-type sealing ring is composed of a V-shaped sealing ring and a D-shaped fixing ring. The V-shaped sealing ring is arranged on the side close to the sealing ring 200. The inner ring surface of the D-shaped fixing ring and the inner ring surface of the V-shaped sealing ring are tightly fitted with the end cover 300 to achieve a sealing effect. The material of the first contact sealing structure 400 is adjusted according to the use temperature. For example, when the actual temperature of the sealing device 10 during use is below 70°C, the material of the first contact sealing structure 400 is selected from nitrile rubber (NBR) and polyurethane (PU). When the actual temperature of the sealing device 10 during use is above 80°C, the first contact sealing structure 400 is selected from fluororubber (FKM).

[0041] See also Figure 2 In one embodiment, the second contact sealing structure 500 is a rotating shaft lip seal ring, which is composed of two metal frames and a sealing lip made of rubber material. The sealing lip has a lip-shaped structure and can fit tightly on the rotating shaft to form an effective seal. The working principle of the rotating shaft lip seal is to form a dynamic sealing oil film between the surface of the rotating shaft and the sealing lip. As the rotating shaft rotates, the sealing lip can dynamically fit along the surface contour of the rotating shaft, thereby effectively preventing fluid leakage. In addition, the sealing lip can also play a role in shock absorption and vibration isolation, thereby improving the operating stability of the rotating shaft. Preferably, the second contact sealing structure 500 is a FB type rotating shaft lip seal ring.

[0042] See also Figures 2 to 4 and Figure 7 and Figure 8 In one embodiment, the distance between the sealing ring 200 and the end cover 300 along the axial direction of the transmission shaft 20 is S. During the operation of the reducer 1, the transmission shaft 20 has a certain amount of movement along its axial direction, and as the operation time of the reducer 1 increases, the temperature at the sealing device 10 continues to increase, and the sealing ring 200 and the end cover 300 will expand as the temperature increases. In order to prevent the normal rotation of the transmission shaft 20 from being affected, 0.5mm≤S≤2mm, for example, S=0.5mm, S=0.8mm, S=1.3mm or S=2mm. If the distance S between the sealing ring 200 and the end cover 300 is too small, friction is easily generated between the sealing ring 200 and the end cover 300 when the transmission shaft 20 moves, affecting the rotation of the transmission shaft 20. If the distance S between the sealing ring 200 and the end cover 300 is too large, the sealing effect of the lubricating oil is affected. In other embodiments, a boss 110 is provided at one end of the sleeve 100 close to the bearing 40. The boss 110 is arranged along the circumference of the sleeve 100. One side of the boss 110 is in contact with the inner ring 401 of the bearing 40, and the other side of the boss 110 is in contact with the sealing ring 200. This can prevent the bearing 40 from moving during operation and causing squeezing of the sealing ring 200, thereby affecting the distance between the sealing ring 200 and the end cover 300.

[0043] See also Figures 2 to 4 In one embodiment, along the radial direction of the transmission shaft 20, the spacing between the sealing ring 200 and the end cover 300 is H1, and the spacing between the end cover 300 and the sleeve 100 is H2. During the operation of the reducer 1, the transmission shaft 20 will generate radial vibration, and as the temperature continues to rise, the sealing ring 200, the end cover 300 and the sleeve 100 will expand with the temperature rise, so 0.25mm≤H1≤1mm, for example, H1=0.25mm, H1=0.5mm, H1=0.8mm or H1=1mm, 0.25mm≤H2≤1mm, for example, H2=0.25mm, H2=0.4mm, H2=0.7mm or H2=1mm. If H1 and H2 are too small, the normal operation of the transmission shaft 20 will be affected, and if H1 and H2 are too large, the sealing effect of the sealing device 10 will be affected.

[0044] See also Fig. 9 and Fig.10 In one embodiment, a through hole 210 is provided on the sealing ring 200. As the lubricating oil in the labyrinth sealing structure accumulates continuously, the pressure of the lubricating oil in the sealing structure gradually increases. During the rotation of the sealing ring 200 with the transmission shaft 20, the lubricating oil on the side of the sealing ring 200 close to the end cover 300 is thrown back to the side of the sealing ring 200 away from the end cover 300 as the sealing ring 200 rotates. The angle between the central axis of the through hole 210 and the central axis of the sealing ring 200 is α, 0<α<90o, for example, α=5o, α=20o, α=50o, α=80o, α=85o. Preferably, along the axial direction of the through hole 210, the aperture of the through hole 210 gradually increases from the end close to the end cover 300 to the end away from the end cover 300.

[0045] See also Figure 2 , Figure 7 and Figure 8In one embodiment, the sealing device 10 further includes an oil cup 600 disposed on the transmission shaft 20, and the oil cup 600 is connected to the labyrinth seal structure. In this embodiment, the transmission shaft 20 is provided with a first channel and a second channel connected to each other, the first channel is distributed along the radial direction of the transmission shaft 20, and the second channel is distributed along the axial direction of the transmission shaft 20. The sleeve 100 is provided with a through hole 210, and the position of the through hole 210 corresponds to the position of the first channel. One end of the first channel is connected to the labyrinth seal structure through the through hole 210 on the sleeve 100, one end of the second channel is connected to the first channel, and the other end of the second channel is connected to the oil cup 600. The oil cup 600 in this application is a one-way oil cup. Before the reducer 1 is running, grease is injected into the labyrinth seal channel through the oil cup 600, so that an oil film is formed between the first contact seal structure 400 and the end cover 300, and an oil film can also be formed between the second contact seal structure 500 and the sealing ring 200, thereby reducing the wear on the first contact seal structure 400 and the second contact seal. At the same time, due to the high viscosity of the grease, the grease between the end cover 300 and the sealing ring 200 can also slow down the flow of the lubricating oil, which is beneficial to enhancing the sealing performance of the sealing device 10. The present application does not limit the type of grease, and the grease can be any grease that can lubricate and seal the sealing device 10. In this embodiment, the grease is calcium sulfonate grease.

[0046] The installation method of the sealing device 10 of the present application is: first install the sleeve 100 on the transmission shaft 20, then install the sealing ring 200 on the sleeve 100, install the first contact sealing structure 400 and the second contact sealing structure 500 on the end cover 300, then install the end cover 300 together with the sealing rings of the first contact sealing structure 400 and the second contact sealing structure 500 on the housing 30, and finally add grease to the sealing part through the oil cup 600. Preferably, before the first contact sealing structure 400 and the second contact sealing structure 500 are installed in the end cover 300, the processed part of the end cover 300 needs to be deburred and the sharp corners need to be blunted to prevent scratches on the first contact sealing structure 400 and the second contact sealing structure 500, and grease is applied to the sliding surfaces of the sealing ring 200 and the end cover 300 in advance in each of the above installation steps.

[0047] The sealing device of the reducer provided by the utility model has a sealing ring fixedly connected to the transmission shaft through a sleeve, an end cover rotatably connected to the transmission shaft, a labyrinth sealing structure formed by the sealing ring and the end cover, a first contact sealing structure arranged between the sealing ring and the end cover, and a second contact sealing structure arranged between the end cover and the sleeve, and the combination of the labyrinth seal and the contact seal can effectively improve the sealing effect of the reducer, so that the reducer can meet the requirements of long-life operation of the reducer under large load and high-speed working conditions without leakage. Therefore, the utility model effectively overcomes some practical problems in the prior art and has high utilization value and use significance.

[0048] 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 technology 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 in the present invention shall still be covered by the claims of the present invention.

Claims

1. A sealing device for a reducer, the reducer comprising a housing and a transmission shaft, the housing being rotatably connected to the transmission shaft, characterized in that: The sealing device comprises: A shaft sleeve, which is sleeved on the transmission shaft, and the shaft sleeve is fixedly connected to the transmission shaft; A sealing ring, which is sleeved on the shaft sleeve and is fixedly connected to the shaft sleeve; An end cover, fixedly mounted on the box body and arranged opposite to the sealing ring; The sealing ring and the end cover form a labyrinth sealing structure, a first contact sealing structure is arranged between the sealing ring and the end cover, and a second contact sealing structure is arranged between the end cover and the shaft sleeve.

2. The sealing device of the reducer according to claim 1, characterized in that: Along the radial direction of the transmission shaft, the distance between the sealing ring and the end cover is H1, 0.25mm≤H≤1mm.

3. The sealing device of the reducer according to claim 1, characterized in that: Along the radial direction of the transmission shaft, the gap between the end cover and the shaft sleeve is H2, 0.25mm≤H2≤1mm.

4. The sealing device of the reducer according to claim 1, characterized in that: Along the axial direction of the transmission shaft, the distance between the sealing ring and the end cover is S, 0.5mm≤S≤2mm.

5. The sealing device of the reducer according to claim 1, characterized in that: The sealing ring is provided with a through hole, and the angle between the central axis of the through hole and the central axis of the sealing ring is α, 0<α<90°.

6. The sealing device of the reducer according to claim 5, characterized in that: Along the axial direction of the through hole, the aperture of the through hole gradually increases from an end close to the end cover to an end away from the end cover.

7. The sealing device of the reducer according to claim 1, characterized in that: The housing is rotatably connected to the transmission shaft via a bearing, a boss is provided at one end of the sleeve close to the transmission bearing, the boss is distributed along the circumference of the sleeve, one side of the boss is fitted with the inner ring of the transmission bearing, and the other side of the boss is fitted with the sealing ring.

8. The sealing device of the reducer according to claim 1, characterized in that: The sealing device further comprises an oil cup arranged on the transmission shaft, and the oil cup is communicated with the labyrinth sealing structure.

9. The sealing device of the reducer according to claim 1, characterized in that: The first contact sealing structure is a VD-type sealing ring, and the second contact sealing structure is a rotating shaft lip sealing ring.

10. A reducer, characterized in that: A sealing device for a reducer comprising any one of claims 1 to 9.

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