Rectangular axis planetary reducer with oil return structure

Abstract

The utility model provides a rectangular axis planetary reducer with an oil return structure. The rectangular axis planetary reducer comprises a box body, an intermediate shaft, an output planet carrier, a bearing seat and an input shaft. A bevel gear pair is arranged at the end of the input shaft and meshed with an input gear pair of the intermediate shaft, and the output planet carrier is in linkage with the intermediate shaft through a compound planetary gear train transmission mechanism. Two sets of symmetrical tapered roller bearings are arranged in the bearing seat, lubricating oil is pressed out from an oil outlet through the oil pumping effect, the lubricating oil flows back to the box body through the oil liquid communication assembly, and circulation of the lubricating oil is achieved. According to further optimization, the main oil return hole is matched with the upper oil return hole and the lower oil return groove, and flowing of lubricating oil is accelerated; the adjusting nut and the lock washer are used for adjusting the bearing clearance and locking the input shaft; the annular limiting step is matched with the check ring to prevent the bearing from moving; the cylindrical roller bearing is additionally arranged, radial run-out of the input shaft is reduced, and operation stability is improved. The speed reducer effectively balances temperature distribution, prolongs the service life of lubricating oil and bearings, and improves the reliability of the speed reducer.

Description

Technical Field

[0001] This utility model specifically relates to a right-angle planetary reducer with an oil return structure. Background Technology

[0002] An orthogonal axis planetary reducer is a transmission device in which the input shaft and output shaft are arranged perpendicularly at 90 degrees. Through the planetary gear transmission within, it reduces the high speed of the motor to a low speed suitable for equipment operation while increasing the output torque. For example, Chinese invention patent application CN119289046A discloses a set of underwater two-stage planetary gear reducers, mainly composed of a housing, input shaft, sun gear shaft, second-stage planetary gears, output planetary carrier, internal gear ring, bearings, etc. When the input shaft rotates, the first bevel gear drives the second bevel gear on the sun gear shaft, achieving the first stage of reduction. The rotation of the sun gear shaft drives the second-stage planetary gears to rotate along the tooth surface trajectory of the internal gear ring, achieving the second stage of reduction. The second-stage planetary gears are fixedly connected to the output planetary carrier, which transmits torque to the output shaft, completing the reduction process.

[0003] Due to the high-speed rotation of the input shaft, the friction between the bearing rollers and the oil seals converts mechanical energy into heat. The temperature inside the input bearing housing of the angle reducer is generally high, especially when the oil return is poor, as the lubricating oil becomes trapped inside the housing, and the temperature inside the housing can be more than ten degrees Celsius higher than the temperature in the oil sump. Excessive temperature inside the bearing housing affects the thermal expansion of the bearing, reducing the axial clearance of the tapered roller bearing. Furthermore, it accelerates the aging of the lubricating oil inside the housing, reduces the oil film viscosity, and increases friction between the rollers and the inner and outer raceways, thus affecting the bearing's lifespan. Simultaneously, under high temperatures, the aging rate of the nitrile rubber oil seals accelerates, affecting the gearbox's sealing performance.

[0004] The current conventional method is to collect the lubricating oil that is thrown up by the rotation of the bevel gear pair into the oil collection groove and then flow into the bearing housing. The disadvantage of this method is that the oil collection is slow and the oil temperature at the bevel gear pair is not much different from the temperature inside the bearing housing, resulting in low heat exchange efficiency. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a right-angle planetary reducer with an oil return structure to address the shortcomings of the prior art. This reduces the internal temperature of the reducer by circulating lubricating oil, thereby improving heat exchange efficiency, extending oil service life, and reducing bearing friction.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a right-angle planetary reducer with an oil return structure, comprising a housing and an intermediate shaft and an output planetary carrier installed within the housing. A bearing housing is connected to the end of the housing, and an input shaft is rotatably connected to the bearing housing. A bevel gear pair is provided at the end of the input shaft facing the inner side of the housing. One end of the intermediate shaft is linked to an input gear pair that meshes with the bevel gear pair. The output planetary carrier is linked to a compound planetary gear transmission mechanism that is linked to the other end of the intermediate shaft. The bearing housing is connected to a transparent cover that is sealed to the input shaft. The bearing housing is characterized by having an oil outlet hole on its side wall, and at least one set of oil inlets on the side wall of the housing corresponding to the compound planetary gear transmission mechanism. The oil outlet hole and the oil inlets are interconnected by an oil communication component. Two sets of tapered roller bearings are provided between the bearing housing and the input shaft. The two sets of tapered roller bearings are arranged sequentially along the axial direction of the input shaft and are symmetrically arranged. The oil outlet hole corresponds to the middle of the two sets of tapered roller bearings.

[0007] Using the above technical solution, the rotation of the planetary gear pairs in the compound planetary gear transmission mechanism agitates the lubricating oil in the gearbox, creating a height difference in the lubricating oil level. The lubricating oil flows from the higher side to the lower side, entering the bearing housing. Then, utilizing the pumping effect of the tapered roller bearings on the input shaft, with two sets of tapered roller bearings symmetrically arranged, the lubricating oil in the bearing housings on both the upper and lower sides is drawn into the oil outlet by the tapered roller bearings and then expelled through the outlet. The expelled lubricating oil returns to the gearbox through the oil communication component. This continuous reciprocating motion ensures that the lubricating oil is constantly circulating between the gearbox, bearing housings, and other structures. This solution has the following technical effects: Through lubricating oil circulation, lubricating oil from high-temperature areas is transferred to low-temperature areas, balancing the temperature distribution inside the reducer and preventing localized overheating. It improves the heat exchange efficiency of the lubricating oil, reduces the aging rate of the lubricating oil, and extends its service life. It reduces bearing thermal expansion caused by high temperatures, preventing the axial clearance of the tapered roller bearings from decreasing and reducing bearing friction. Increasing the viscosity of the lubricating oil film reduces friction between the rollers and the inner and outer raceways, extending the service life of the tapered roller bearings. It also reduces the impact of high temperatures on the oil seals, slows down the aging of nitrile rubber oil seals, and improves the sealing performance of the gearbox. The use of symmetrically arranged tapered roller bearings optimizes the force distribution on the bearings, improving the stability and reliability of the transmission system.

[0008] The aforementioned orthogonal axis planetary reducer with an oil return structure can be further configured as follows: the oil communication assembly includes an oil outlet connector connected to an oil outlet hole, the oil outlet connector is connected to a first hose, the first hose is connected to a three-way connector, the three-way connector is connected to a first check valve and a second hose respectively, the first check valve is unidirectionally connected to a first oil inlet connector, the second hose is connected to a second check valve, the second check valve is unidirectionally connected to a second oil inlet connector, and the side wall of the housing is provided with two sets of oil inlet holes corresponding to the compound planetary gear transmission mechanism, the first oil inlet connector is connected to one set of oil inlet holes, and the second oil inlet connector is connected to the other set of oil inlet holes.

[0009] Using the above technical solution, when the input shaft rotates at high speed, the two sets of tapered roller bearings in the bearing housing generate a pumping effect, forcing lubricating oil out from the oil outlet. The lubricating oil enters the first hose through the oil outlet connector and then flows to the tee connector. The tee connector splits the lubricating oil in two directions: one part flows to the first check valve, and the other part flows to the second hose. The first and second check valves ensure that the lubricating oil can only flow in one direction, preventing backflow. The lubricating oil enters the two sets of oil inlets on the side wall of the housing through the first and second oil inlets, and finally flows into the compound planetary gear transmission mechanism area. In the compound planetary gear transmission mechanism, the rotation of the planetary gear pairs agitates the lubricating oil, creating a height difference within the housing. The lubricating oil flows from the side with the higher liquid level to the side with the lower level, entering the bearing housing. The lubricating oil flows back to the bearing housing through the return oil hole, completing the circulation. This solution has the following technical effects: through the agitation of the planetary gear pairs and the control of the one-way check valve, the lubricating oil forms a dynamic circulation between the housing and the bearing housing. This ensures that the lubricating oil in high-temperature areas can be promptly transferred to low-temperature areas, preventing localized overheating. Simultaneously, the continuous flow of lubricating oil improves heat exchange efficiency, reduces its aging rate, and extends its service life.

[0010] The aforementioned orthogonal axis planetary reducer with an oil return structure can be further configured as follows: the side wall of the bearing housing is provided with a main oil return hole that extends through the bearing housing axially, the middle of the main oil return hole is connected to an upper oil return hole, the upper oil return hole is distributed above the two sets of tapered roller bearings and the upper oil return hole connects the inner cavity of the bearing housing with the main oil return hole, and the end face of the cover facing the bearing housing is provided with a lower oil return groove, the lower oil return groove is distributed below the two sets of tapered roller bearings and the lower oil return groove connects the inner cavity of the bearing housing with the main oil return hole.

[0011] Using the above technical solution, the main oil return hole is connected to the housing to allow lubricating oil to enter the main oil return hole from the housing and then flow into the bearing housing through the upper oil return hole and lower oil return groove, respectively. Simultaneously, due to the symmetrical arrangement of the two sets of tapered roller bearings, the upper tapered roller bearing forces the lubricating oil from the upper oil return hole into the oil outlet hole; the lower tapered roller bearing forces the lubricating oil from the lower oil return groove into the oil outlet hole. The simultaneous operation of both sets of tapered roller bearings accelerates the flow efficiency of the lubricating oil.

[0012] The aforementioned orthogonal axis planetary reducer with oil return structure can be further configured such that: an adjusting nut is also fitted around the outer periphery of the input shaft, the adjusting nut is detachably connected to the input shaft, the adjusting nut is distributed between the tapered roller bearing and the through cover, and a retaining washer is also provided between the adjusting nut and the tapered roller bearing, the retaining washer being fitted around the outer periphery of the input shaft.

[0013] Using the above technical solution, the adjusting nut and locking washer can adjust the axial clearance of the two sets of tapered roller bearings, while locking the input shaft to the bearing housing.

[0014] The aforementioned orthogonal axis planetary reducer with oil return structure can be further configured as follows: the inner circumferential surface of the bearing housing is provided with an annular limiting step, a stop ring is provided between the cover and the tapered roller bearing, two sets of tapered roller bearings are distributed between the stop ring and the annular limiting step, and the upper part of one set of tapered roller bearings is engaged with the annular limiting step, while the lower part of the other set of tapered roller bearings is in contact with the stop ring.

[0015] By adopting the above technical solution, the annular limiting step and the stop ring cooperate to limit the movement of the two sets of tapered roller bearings and prevent the two sets of tapered roller bearings from moving up and down.

[0016] The aforementioned orthogonal axis planetary reducer with oil return structure can be further configured such that: a set of cylindrical roller bearings is provided at the inner end of the bearing housing away from the cover, and the cylindrical roller bearings are sleeved on the outer circumference of the input shaft.

[0017] By adopting the above technical solution, the cylindrical roller bearing serves to further support the input shaft, reduce the radial runout of the input shaft, and improve the operational stability of the input shaft.

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a cross-sectional schematic diagram of an embodiment of the present utility model;

[0020] Figure 2 This is a perspective view of an embodiment of the present utility model;

[0021] Figure 3This is a schematic diagram of the interior of the bearing housing according to an embodiment of the present utility model;

[0022] Figure 4 This is a schematic diagram of the transparent cover according to an embodiment of the present utility model;

[0023] Figure 5 for Figure 1 A magnified view of a portion of point A in the middle.

[0024] Labeling notes: 1. Housing, 1a. Oil inlet; 2. Intermediate shaft, 4. Output planetary carrier; 5. Bearing seat, 5a. Oil outlet, 5b. Main return oil hole, 5c. Upper return oil hole, 5d. Annular limiting step; 6. Input shaft, 7. Bevel gear pair, 8. Input gear pair, 9. Compound planetary gear transmission mechanism; 10. Through cover, 10a. Tapered roller bearing; 11. Oil outlet connector; 12. First hose; 13. T-connector; 14. First check valve; 15. Second hose; 16. First oil inlet connector; 17. Second check valve; 18. Second oil inlet connector; 19. Adjusting nut; 20. Locking washer; 21. Locking ring; 22. Cylindrical roller bearing; 23. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] like Figures 1 to 5The right-angle planetary reducer with an oil return structure shown includes a housing 1, an intermediate shaft 2 and an output planetary carrier 4 installed inside the housing 1. A bearing housing 5 is connected to one end of the housing 1, and an input shaft 6 is rotatably connected to the bearing housing 5. A bevel gear pair 7 is provided at the end of the input shaft 6 facing inwards from the housing 1. One end of the intermediate shaft 2 is linked to an input gear pair 8 that meshes with the bevel gear pair 7. The output planetary carrier 4 is linked to a compound planetary gear transmission mechanism 9 that is linked to the other end of the intermediate shaft 2. The bearing housing 5 is connected to a sealed section that is sealed to the input shaft 6. The connecting cover 10 has an oil outlet 5a on the side wall of the bearing housing 5. The side wall of the housing 1 has two sets of oil inlets 1a corresponding to the compound planetary gear transmission mechanism 9. The oil outlet 5a and the oil inlets 1a are connected to each other by an oil communication component. Two sets of tapered roller bearings 11 are provided between the bearing housing 5 and the input shaft 6. The two sets of tapered roller bearings 11 are arranged sequentially along the axial direction of the input shaft 6 and are symmetrically arranged. The oil outlet 5a corresponds to the middle of the two sets of tapered roller bearings 11. The oil connection assembly includes an oil outlet connector 12 connected to an oil outlet port 5a. The oil outlet connector 12 is connected to a first hose 13. The first hose 13 is connected to a three-way connector 14. The three-way connector 14 is connected to a first check valve 15 and a second hose 16. The first check valve 15 is connected to a first oil inlet connector 17 in one direction. The second hose 16 is connected to a second check valve 18 in one direction. The second check valve 18 is connected to a second oil inlet connector 19 in one direction. The side wall of the housing 1 is provided with two sets of oil inlets 1a corresponding to the compound planetary gear transmission mechanism 9. The first oil inlet connector 17 is connected to one set of oil inlets 1a, and the second oil inlet connector 19 is connected to the other set of oil inlets 1a.

[0027] When the input shaft 6 rotates at high speed, the two sets of tapered roller bearings 11 in the bearing housing 5 generate a pumping effect, forcing lubricating oil out from the oil outlet 5a. The lubricating oil enters the first hose 13 through the oil outlet connector 12, and then flows to the three-way connector 14. The three-way connector 14 splits the lubricating oil in two directions: one part flows to the first check valve 15, and the other part flows to the second hose 16. The first check valve 15 and the second check valve 18 ensure that the lubricating oil can only flow in one direction, preventing backflow. The lubricating oil enters the two sets of oil inlets 1a on the side wall of the housing 1 through the first oil inlet connector 17 and the second oil inlet connector 19, and finally flows into the area of ​​the compound planetary gear transmission mechanism 9. In the compound planetary gear transmission mechanism 9, the rotation of the planetary gear pairs agitates the lubricating oil, creating a height difference within the housing 1. The lubricating oil flows from the side with the higher liquid level to the side with the lower liquid level, entering the bearing housing 5. The lubricating oil flows back to the bearing housing 5 through the oil return hole, completing the circulation.

[0028] The bearing housing 5 has a main oil return hole 5b extending axially through its side wall. An upper oil return hole 5c is connected to the middle of the main oil return hole 5b. The upper oil return hole 5c is located above the two sets of tapered roller bearings 11 and connects the inner cavity of the bearing housing 5 to the main oil return hole 5b. A lower oil return groove 10a is located on the end face of the cover 10 facing the bearing housing 5. The lower oil return groove 10a is located below the two sets of tapered roller bearings 11 and connects the inner cavity of the bearing housing 5 to the main oil return hole 5b. The main oil return hole 5b is connected to the housing 1, allowing lubricating oil to enter the main oil return hole 5b from the housing 1 and flow into the bearing housing 5 through the upper oil return hole 5c and the lower oil return groove 10a. Simultaneously, due to the symmetrical arrangement of the two sets of tapered roller bearings 11, the upper tapered roller bearing 11 forces the lubricating oil from the upper oil return hole 5c into the oil outlet hole 5a; while the lower tapered roller bearing 11 forces the lubricating oil from the lower oil return groove 10a into the oil outlet hole 5a. The simultaneous operation of the two sets of tapered roller bearings 11 accelerates the flow efficiency of the lubricating oil.

[0029] An adjusting nut 20 is fitted around the outer periphery of the input shaft 6. The adjusting nut 20 is detachably connected to the input shaft 6. The adjusting nut 20 is distributed between the tapered roller bearing 11 and the cover 10. A retaining washer 21 is also provided between the adjusting nut 20 and the tapered roller bearing 11, and the retaining washer 21 is fitted around the outer periphery of the input shaft 6. The adjusting nut 20 and the retaining washer 21 can adjust the axial clearance of the two sets of tapered roller bearings 11, and at the same time lock the input shaft 6 onto the bearing housing 5.

[0030] The bearing housing 5 has an annular limiting step 5d on its inner circumferential surface. A retaining ring 22 is provided between the cover 10 and the tapered roller bearing 11. Two sets of tapered roller bearings 11 are distributed between the retaining ring 22 and the annular limiting step 5d. The upper part of one set of tapered roller bearings 11 engages with the annular limiting step 5d, while the lower part of the other set of tapered roller bearings 11 contacts the retaining ring 22. The engagement of the annular limiting step 5d and the retaining ring 22 can limit the movement of the two sets of tapered roller bearings 11, preventing them from moving up and down.

[0031] A set of cylindrical roller bearings 23 is provided at the inner end of the bearing housing 5 away from the cover 10, and the cylindrical roller bearings 23 are sleeved on the outer circumference of the input shaft 6. The function of the cylindrical roller bearings 23 is to further support the input shaft 6, reduce the radial runout of the input shaft 6, and improve the running stability of the input shaft 6.

[0032] The lubrication principle of this embodiment is as follows: The rotation of the planetary gear pairs in the compound planetary gear transmission mechanism 9 agitates the lubricating oil in the housing 1, creating a height difference in the lubricating oil level within the housing 1. The lubricating oil flows from the higher side to the lower side, i.e., into the bearing housing 5. Then, utilizing the pumping effect of the tapered roller bearings 11 on the input shaft 6, with two sets of tapered roller bearings 11 symmetrically arranged, the lubricating oil in the bearing housings 5 ​​on both the upper and lower sides is drawn into the oil outlet 5a by the tapered roller bearings, and then expelled through the oil outlet 5a. The expelled lubricating oil returns to the housing 1 through the oil communication component (which contains a check valve to ensure that the oil only flows from the oil outlet 5a into the oil inlet 1a). This continuous reciprocating motion ensures that the lubricating oil constantly circulates between the housing 1, bearing housing 5, and other structures.

[0033] By circulating the lubricating oil, the high-temperature region's lubricating oil is transferred to the low-temperature region, balancing the temperature distribution inside the reducer and preventing localized overheating. This improves the heat exchange efficiency of the lubricating oil, reduces its aging rate, and extends its service life. It also reduces bearing thermal expansion caused by high temperatures, preventing a decrease in the axial clearance of the tapered roller bearing 11 and reducing bearing friction. Furthermore, it increases the oil film viscosity of the lubricating oil, reducing friction between the rollers and the inner and outer raceways, thus extending the service life of the tapered roller bearing 11. Finally, it reduces the impact of high temperatures on the oil seal, slowing down the aging rate of the nitrile rubber oil seal and improving the gearbox's sealing performance. The symmetrical arrangement of the tapered roller bearings 11 optimizes the bearing's stress distribution, improving the stability and reliability of the transmission system.

Claims

1. A direct-axle planetary reducer with oil return structure, comprising a box body and a middle shaft and an output planet carrier installed in the box body, an end of the box body being connected with a bearing seat, the bearing seat being rotationally connected with an input shaft, the input shaft being provided with a bevel gear pair at an end thereof towards the inside of the box body, one end of the middle shaft being connected with an input gear pair in meshing transmission with the bevel gear pair, the output planet carrier being connected with a compound planetary gear train transmission mechanism connected with the other end of the middle shaft, the bearing seat being connected with a transparent cover in sealed connection with the input shaft, characterized in that: The side wall of the bearing seat is provided with an oil outlet hole, the side wall of the box body is provided with at least one group of oil inlet holes corresponding to the composite planetary gear train transmission mechanism, the oil outlet hole and the oil inlet hole are communicated with each other through the oil liquid communication assembly, and the bearing seat and the input shaft are provided with two groups of tapered roller bearings.

2. The direct and orthogonal shaft planetary speed reducer having an oil return structure according to claim 1, characterized by: The oil liquid communication assembly comprises an oil outlet joint connected with the oil outlet hole, the oil outlet joint is communicated with a first hose, the first hose is communicated with a three-way joint, the three-way joint is respectively communicated with a first check valve and a second hose, the first check valve is unidirectionally communicated with a first oil inlet joint, the second hose is communicated with a second check valve, the second check valve is unidirectionally communicated with a second oil inlet joint, the side wall of the box body is provided with two groups of oil inlet holes corresponding to the composite planetary gear train transmission mechanism, the first oil inlet joint is communicated with one group of oil inlet holes, and the second oil inlet joint is communicated with the other group of oil inlet holes.

3. The direct and orthogonal shaft planetary speed reducer with an oil return structure according to claim 1 or 2, characterized in that: The side wall of the bearing seat is provided with a main oil return hole penetrating in the axial direction of the bearing seat, the middle part of the main oil return hole is communicated with an upper oil return hole, the upper oil return hole is distributed above the two groups of tapered roller bearings and communicates the inner cavity of the bearing seat with the main oil return hole, the end face of the transparent cover facing the bearing seat is provided with a lower oil return groove, the lower oil return groove is distributed below the two groups of tapered roller bearings and communicates the inner cavity of the bearing seat with the main oil return hole.

4. The direct and orthogonal shaft planetary speed reducer with an oil return structure according to claim 1 or 2, characterized in that: The outer periphery of the input shaft is further provided with an adjusting nut, the adjusting nut is detachably connected with the input shaft, the adjusting nut is distributed between the tapered roller bearings and the transparent cover, and a stop washer is further arranged between the adjusting nut and the tapered roller bearings.

5. The direct and orthogonal shaft planetary speed reducer having an oil return structure according to claim 4, characterized by: The inner periphery of the bearing seat is provided with an annular limiting step, a stop ring is arranged between the transparent cover and the tapered roller bearings, the two groups of tapered roller bearings are distributed between the stop ring and the annular limiting step, the upper part of one group of tapered roller bearings is matched with the annular limiting step, and the lower part of the other group of tapered roller bearings is in contact with the stop ring.

6. The direct and orthogonal shaft planetary speed reducer having an oil return structure according to claim 1, characterized by: The inner end of the bearing seat away from the transparent cover is provided with one group of cylindrical roller bearings, and the cylindrical roller bearings are sleeved on the outer periphery of the input shaft.

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