Planet row speed reducer for coaxial distributed driving and assembling method

Abstract

The invention relates to the technical field of automobile part structures, in particular to a planet row speed reducer for coaxial distributed driving and an assembling method. Comprising a shell, an input shaft, a plurality of planetary gears, a gear ring, a plurality of planetary shafts and a planetary carrier, and one end of the input shaft is connected with power output equipment; the planetary gears are arranged at intervals in the circumferential direction of the input shaft and are in meshing transmission connection with the input shaft. The inner side of the gear ring is meshed with the planetary gear; one end of the planetary shaft is connected to the planetary gear in a manner of rotating around the axis of the planetary shaft through a first bearing structure, and the planetary shaft and the planetary gear are coaxially arranged; the planet carrier is sleeved on the input shaft in a manner of rotating around the axis of the input shaft; the planet carrier is fixedly connected with the other end of the planet shaft in the rotating direction around the axis of the input shaft; the revolution axis of the planetary gear, the rotation axis of the planet carrier and the axis of the input shaft coincide. The speed reducer has the advantages of being simple in structure, good in NVH effect, compact in structure and convenient to arrange.

Description

Technical Field

[0001] The invention relates to the technical field of automobile component structures, and in particular to a planetary gear reducer for coaxial distributed drive and an assembly method thereof. Background Art

[0002] With the development of the new energy industry, passenger car customers have strong demands for acceleration performance, body control, off-road climbing and other functions. Correspondingly, this will drive the development of new energy electric drive assemblies towards high speed, high torque and high power density.

[0003] The traditional single motor + reducer + differential electric drive solution can ensure that the vehicle is driven when the left and right wheels have different speeds, but it cannot actively control the speed and torque of the left and right wheels. In extreme road conditions such as ice and desert, the wheels will inevitably slip, affecting driving safety and performance.

[0004] The distributed drive solution is a dual-motor electric drive solution, which uses one motor on each side to match two reducers on the left and right sides. The function of the differential is realized through motor control, and the speed and torque of the left and right wheel ends can be independently adjusted in real time to meet the customer's driving needs.

[0005] For distributed drive solutions, there are coaxial solutions and parallel axis solutions. The coaxial solution is relatively more compact and has higher power density. Currently, there are several types of coaxial distributed drive structures:

[0006] 1. Coaxial distributed drive structure with NW type planetary gear structure

[0007] The NW planetary gear has two center gears (sun gear and ring gear) without common planetary gears. This structure enables the NW planetary gear to achieve a larger speed ratio in the same space, and has the advantages of compact structure, large load-bearing capacity and transmission power range. The disadvantage is that the NW planetary gear is easily affected by the overturning torque of the planetary gear, which greatly reduces the NVH effect of the vehicle.

[0008] 2. Coaxial distributed drive structure with offset coaxial structure

[0009] The planetary gear row of this structure is coaxially arranged with the motor, but the reducer is not coaxial with the motor. This design combines the advantages of planetary gear transmission and coaxial arrangement, and can effectively improve the integration and transmission efficiency of the electric drive system. The disadvantage is that the gear rotation line is not coaxial with the output line, and it occupies a large space in the X or Z direction, which is not conducive to layout.

[0010] The existing coaxial distributed drive structures have many problems, and there is an urgent need for a structure that can ensure the vehicle NVH effect and is convenient for layout. Summary of the invention

[0011] The purpose of this application is to solve the deficiencies of the above-mentioned background technology and to provide a planetary gear reducer and an assembly method for coaxial distributed drive.

[0012] The technical solution of the present application is: a planetary gear reducer for coaxial distributed drive, comprising a housing, and also comprising:

[0013] An input shaft, one end of which is connected to a power output device;

[0014] A plurality of planetary gears, the plurality of planetary gears are arranged at intervals along the circumference of the input shaft with the axis of the input shaft as the center, the planetary gears are meshed and transmission-connected with the input shaft and driven by the input shaft to revolve around the axis of the input shaft;

[0015] A gear ring, the outer side of which is fixed to the housing and the inner side of which is meshed with the planetary gear;

[0016] A plurality of planetary shafts, one end of each of which is arranged along an axis parallel to the input shaft and passes through the planetary gear, and is connected to the planetary gear rotatably around its own axis through a first bearing structure, and the planetary shaft and the planetary gear are arranged coaxially;

[0017] A planet carrier, the planet carrier is sleeved on the input shaft and can rotate around the axis of the input shaft through a second bearing structure, and the planet carrier is fixedly connected to the other end of the planet shaft in the rotation direction around the axis of the input shaft;

[0018] The revolution axis of the planetary gear, the rotation axis of the planet carrier and the input shaft axis coincide with each other.

[0019] According to a planetary reducer for coaxial distributed drive provided in the present application, the planet carrier is a hollow cavity structure, including a first side close to the input shaft and a second side away from the input shaft; the first side and the second side are arranged axially at intervals, and mounting holes corresponding to the planetary shafts are opened on the first side and the second side; both ends of the planetary shaft are passed through the mounting holes to arrange the planetary gears between the first side and the second side.

[0020] According to a planetary reducer for coaxial distributed drive provided in the present application, an oil receiving pan is arranged in the shell; the oil receiving pan is a hollow cavity structure fixed on the first side, and an oil distribution structure is arranged in the oil receiving pan; one end of the oil distribution structure is connected to the oil channel on the shell, and the other end passes through the first side axially and goes deep into the planetary carrier.

[0021] According to a planetary gear reducer for coaxial distributed drive provided by the present application, a through hole for discharging oil in the planet carrier is provided on the second side.

[0022] According to a planetary gear reducer for coaxial distributed drive provided by the present application, a plurality of through holes are arranged on the second side, and the plurality of through holes and the mounting holes of the corresponding planetary shafts are evenly staggered with the axis of the input shaft as the center.

[0023] According to a planetary gear reducer for coaxial distributed drive provided in the present application, the first bearing structure includes a retaining ring fixed to the inner side of the planetary gear and first bearings disposed on both axial sides of the retaining ring.

[0024] According to a planetary reducer for coaxial distributed drive provided in the present application, the planetary shaft is a hollow shaft-like structure with an opening on one side, and the planetary shaft is provided with an oil outlet hole radially connecting the inner cavity of the planetary shaft and the outer first bearing.

[0025] According to a planetary reducer for coaxial distributed drive provided in the present application, the second bearing structure includes a second bearing and a third bearing which are arranged on both sides of the axial direction of the planetary carrier and correspond to the first side and the second side respectively; the second bearing is fixed in the axial direction between the first side and the input shaft by a retaining ring; the third bearing is fixed in the axial direction between the second side and the input shaft by a retaining ring.

[0026] According to a planetary gear reducer for coaxial distributed drive provided in the present application, an oil outlet for spraying oil to the second bearing is provided on the housing.

[0027] According to a planetary gear reducer for coaxial distributed drive provided by the present application, the third bearing is located at the oil outlet position on the planet carrier.

[0028] A planetary gear reducer for coaxial distributed drive provided in the present application also includes a fourth bearing located on the side of the planet carrier away from the input shaft; an oil outlet for spraying oil to the fourth bearing is provided on the housing.

[0029] The present application also provides a method for assembling a planetary gear reducer for coaxial distributed drive, wherein the method is used for assembling any one of the above-mentioned planetary gear reducers for coaxial distributed drive, and comprises:

[0030] Selecting a corresponding snap ring based on the axial width of the first bearing structure and the installation width of the planet carrier;

[0031] Assembling the selected snap ring onto the planetary gear, and then assembling the first bearing structure onto the planetary gear;

[0032] Pass the planetary shaft axially through the planetary shaft to assemble the planetary gear to the planetary carrier, and complete the installation of the planetary gear, planetary shaft and planetary carrier, and proceed in sequence until all the planetary gears and planetary shafts are assembled to the planetary carrier;

[0033] Then assemble the planet carrier onto the input shaft to complete the assembly of the reducer.

[0034] According to a planetary gear reducer assembly method for coaxial distributed drive provided in the present application, the method for selecting a corresponding retaining ring based on the axial width of the first bearing structure and the installation width of the planetary carrier includes: recording the installation width C1 of the corresponding planetary gear on the planetary carrier, measuring the axial widths of the two first bearings on both sides of the axial direction of the retaining ring in the first bearing as A1 and A2, and the optional retaining ring thickness is C1-A1-A2-a, where a is a set value.

[0035] According to a method for assembling a planetary reducer for coaxial distributed drive provided in the present application, the method for assembling a planetary gear to a planetary carrier by axially passing through a planetary shaft comprises: placing a planetary gear equipped with a first bearing structure into the planetary carrier, making the inner ring of the first bearing structure, the planetary gear and the corresponding mounting hole on the planetary carrier coaxial, inserting a guide pin into the mounting hole and the inner ring of the first bearing structure; then, the planetary shaft to be assembled is interference pressed into the mounting hole of the planetary carrier along the axial direction until the guide pin is completely ejected, thereby completing the installation of the planetary shaft, planetary gear and planetary carrier.

[0036] The advantages of the present application are as follows: 1. The planetary gears of the present application are evenly distributed along the circumference of the input shaft between the ring gear and the planet carrier, and the planetary gears mesh with the ring gear and the input shaft respectively. Such an arrangement structure can offset the forces of the planetary gears in the axial and radial directions, and the operation of the entire planetary gear set is smoother, and the torque balance and NVH performance are better; at the same time, the planetary gears and planetary shafts of the present application are integrated in the planet carrier, and the structure is compact and compact, the planetary gear revolution axis coincides with the input shaft axis, the overall space occupied is extremely small, and the structure arrangement is more convenient; furthermore, the present application connects the planetary gears, planetary shafts, planet carrier and input shaft through a bearing structure, and the planetary gear set structure is more stable in force during operation, operates smoothly, has excellent support stability, and has greatly improved the safety factor;

[0037] 2. The planet carrier of the present application is a hollow cavity structure. On the one hand, the planet carrier of the hollow cavity can facilitate the arrangement of the planetary gears and the planetary shafts, so that the entire planetary gear structure occupies less space. On the other hand, a gap can be formed inside the planet carrier for the passage of oil, which facilitates the flow of lubricating oil, etc. The oil distribution is more uniform and sufficient, so that the operation of the entire planetary gear is smoother;

[0038] 3. The present application installs an oil receiving pan on the first side of the planetary carrier. The oil receiving pan is fixed on the planetary carrier and can rotate with the planetary carrier, so as to evenly distribute the oil into the planetary carrier along the axial direction. It is not necessary to configure a dedicated electronic pump or other oil driving structure, and the oil can be distributed into the planetary carrier to facilitate lubrication of the planetary gears, bearings and planetary shafts in the planetary carrier, and the oil flows more smoothly.

[0039] 4. The present application sets a through hole on the second side of the planet carrier, which can discharge the oil in the planet carrier, facilitating the circulation of the oil in the planet carrier, and also facilitates the oil to enter the planet carrier from the other side. The construction of the through hole reduces the obstruction to the flow of the oil, making the flow of the oil in the planet carrier smoother;

[0040] 5. The through holes and the mounting holes on the second side of the present application are arranged in a staggered manner, which can, on the one hand, allow the oil to fully contact the planetary shaft passing through the mounting holes, and on the other hand, allow the oil to flow in and out evenly on the second side, thereby achieving a better lubrication effect on the internal structure of the oil;

[0041] 6. The first bearing of the present application has a simple structure. Two sets of first bearings are arranged between the planetary gear and the planetary shaft through a retaining ring, which provides excellent support stability for the planetary gear, and the operation of the planetary gear is smoother and more stable without generating interference noise, etc.;

[0042] 7. The planetary shaft of the present application is a hollow shaft-shaped structure. The open side of the planetary shaft can receive the oil discharged from the oil receiving pan, and then distribute the oil radially to the first bearing structure, so that the oil is thrown radially to the first bearing structure, and the oil is distributed more evenly;

[0043] 8. The second bearing structure of the present application supports the planetary carrier by installing the second bearing and the third bearing on both sides of the planetary carrier, so that the rotation of the planetary carrier on the input shaft is more stable and smooth, the structural stability of the planetary carrier is greatly enhanced, and the power output is more stable;

[0044] 9. The present application sets an oil outlet on the housing to facilitate oil spraying to the second bearing, so that the second bearing always has lubricating oil flowing during use, and the second bearing runs more smoothly;

[0045] 10. The third bearing of the present application is located at the oil outlet of the planetary carrier, and the third bearing is always in the lubricating oil, so the lubrication effect is guaranteed, and the operation of the third bearing is smooth and stable;

[0046] 11. The present application also provides a fourth bearing on the planet carrier, which facilitates the installation between the planet carrier and the housing. In order to facilitate the operation of the fourth bearing, the present application also provides an oil outlet corresponding to the fourth bearing, so that the fourth bearing is in lubricating grease;

[0047] 12. The present application also provides an assembly method. The assembly method of the present application fully considers the size relationship between the various components, and can accurately assemble the planetary gear, the planetary shaft, and the first bearing structure to the planetary carrier. The overall assembly method is orderly, simple and efficient.

[0048] 13. The present application selects the retaining ring by considering the installation width of the first bearing, the retaining ring and the planet carrier, so that the first bearing and the retaining ring can be assembled into the planetary gear, and the subsequent installation of the planetary shaft, the first bearing and the planet carrier can also correspond precisely;

[0049] 14. The assembly method of the planetary shaft in the present application is very simple. By setting a guide pin shaft, the planetary gear, the first bearing and the planetary carrier can be prevented from being dislocated during the assembly process of the planetary shaft, so that the assembly of the planetary shaft is more accurate and the assembly efficiency is greatly improved.

[0050] The reducer of the present application has a simple structure and can effectively improve the NVH effect of the vehicle. The planetary gearbox used in the present application has a compact structure, occupies a small space, and is easy to arrange. The planetary gearbox structure in the entire reducer is tightly and stably arranged, and has excellent safety and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 : Schematic diagram of the coaxial distributed drive structure of the present application;

[0052] Figure 2 : Schematic diagram of the cross section of the reducer of the present application;

[0053] Figure 3 : A side view of the reducer of the present application;

[0054] Figure 4 : Schematic diagram of oil flow in the reducer of the present application;

[0055] Figure 5 : Planet carrier shaft view of the present application (first side one side);

[0056] Figure 6 : Planet carrier shaft view of the present application (second side one side);

[0057] Wherein: 1—input shaft; 2—planetary gear; 3—gear ring; 4—planetary shaft; 5—planet carrier; 51—first side; 52—second side; 53—mounting hole; 54—through hole;

[0058] 6—housing; 7—oil pan; 8—retaining ring; 9—first bearing; 10—second bearing; 11—third bearing; 12—fourth bearing. DETAILED DESCRIPTION

[0059] The embodiments of the present application are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0060] In the description of the present application, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0061] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0062] The present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0063] The present application is directed to a planetary gear reducer for coaxial distributed drive. The reducer of the present application has a planetary gear structure. Each distributed drive electric drive assembly contains two planetary gear reducers on the left and right and two motors. Figure 1 As shown. The planetary gears of the reducer of the present application are evenly distributed along the circumference of the input shaft between the ring gear and the planet carrier, and the planetary gears are meshed with the ring gear and the input shaft respectively. Such an arrangement structure can offset the forces of the planetary gears in the axial and radial directions, and the operation of the entire planetary gear set is smoother, and the torque balance and NVH performance are better; at the same time, the planetary gears and planetary shafts of the present application are integrated in the planet carrier, and the structure is compact and compact, the axis of revolution of the planetary gears coincides with the axis of the input shaft, the overall space occupied is extremely small, and the structure is more convenient; furthermore, the present application connects the planetary gears, planetary shafts, planet carrier and input shaft through a bearing structure, and the planetary gear set structure is more stable in force during operation, operates smoothly, has excellent support stability, and has greatly improved the safety factor.

[0064] Specifically, Figures 1 to 6As shown, a planetary gear reducer for coaxial distributed drive of the present application includes a housing 6, an input shaft 1, a plurality of planetary gears 2, a plurality of planetary shafts 4, a ring gear 3 and a planet carrier 5. One end of the input shaft 1 is connected to a power output device, and the power output device transmits power to the reducer through the input shaft. A spline structure is provided on the input shaft 1 to connect with the power output device, and the power output device is a structure such as a motor. The ring gear 3 is an annular structure fixed in the housing 6, and a rack structure is provided on the inner side of the circumference of the ring gear 3. A plurality of planetary gears 2 are evenly spaced along the circumference of the input shaft 1 with the axis of the input shaft 1 as the center. The plurality of planetary gears 2 of the present application are evenly spaced around the input shaft 1, as shown in FIG. Figure 3 As shown, three planetary gears 2 are arranged on the input shaft 1 of the present application, and the three planetary gears 2 are spaced 120° apart. The planetary gears 2 are meshed and connected with the input shaft 1 and driven by the input shaft 1 to revolve around the axis of the input shaft 1. The planetary gears 2 are meshed with the rack structure inside the ring gear 3. Because the planetary gears 2 are evenly distributed between the ring gear 3 and the input shaft 1, the forces between them can offset each other in the radial direction, and the smoothness of the planetary gears 2 during operation is excellent. Driven by the input shaft 1, the planetary gears 2 rotate around the axis of the input shaft 1, that is, they revolve around the input shaft 1 as the center, and the planetary gears 2 themselves rotate between the input shaft 1 and the ring gear 3, and rotate around their own axis, that is, they rotate on their own axis.

[0065] One end of the planetary shaft 4 is arranged in the planetary gear 2 along the axis direction parallel to the input shaft 1. The planetary gear 2 and the planetary shaft 4 are in one-to-one correspondence. Each planetary gear 2 is provided with a planetary shaft 4. The planetary shaft 4 is connected to the planetary gear 2 in a rotatable manner around its own axis through a first bearing structure, that is, the planetary shaft 4 and the planetary gear 2 are relatively rotatably connected in the direction around the axis of the planetary gear 2. The planetary shaft 4 is coaxially arranged with the planetary gear 2 and is fixedly connected in the rotation direction around the axis of the input shaft 1. The planetary shaft 4 is used to output the power of the planetary gear 2.

[0066] The planet carrier 5 is sleeved on the input shaft 1 and can rotate around the axis of the input shaft 1 through the second bearing structure. The planet carrier 5 is fixedly connected to the other end of the planet shaft 4 in the direction of rotation around the axis of the input shaft 1. In other words, the planet carrier 5 is driven by the planet shaft 4 to rotate around the axis of the input shaft 1, and the planet carrier 5 and the input shaft 1 can rotate relative to each other in the direction of the axis around the input shaft 1. The revolution axis of the planetary gear 2, the rotation axis of the planet carrier 5 and the axis of the input shaft 1 coincide. A spline structure is provided on the planet carrier 5, which is connected to the half shaft of the whole vehicle through the spline structure to transmit power to the half shaft of the whole vehicle.

[0067] The power transmission route of the present application is that the power output device transmits power to the input shaft 1, the input shaft 1 transmits power to the planetary gear 2, the planetary gear 2 transmits power to the planetary shaft 4, the planetary shaft 4 transmits power to the planetary carrier 5, and the planetary carrier 5 transmits power to the half shaft of the whole vehicle.

[0068] Since the planetary gears 2 of the present application are evenly spaced between the input shaft 1 and the ring gear 3, the forces in the radial direction can offset each other, and the operation is extremely smooth without jamming or affecting the NVH performance. In addition, the axes of the planetary gears 2, planetary shafts 4, planetary carriers 5 and input shaft 1 of the present application coincide with each other and are connected to each other through a bearing structure, which can effectively eliminate the deflection effect in the axial direction and ensure that the forces in the axial direction can also offset each other, thereby improving the stability and smoothness of the overall reducer operation.

[0069] When the reducer of the present application is actually installed: the corresponding retaining ring 8 is selected based on the axial width of the first bearing structure and the installation width of the planetary carrier 5; the selected retaining ring 8 is assembled to the planetary gear 2 (the planetary gear 2 is an annular structure, the outer ring of the planetary gear 2 is provided with a rack structure meshing with the input shaft 1 and the ring gear 3, and the inner ring is provided with a circle of grooves along the circumferential direction for installing the retaining ring 8), and then the first bearing structure is assembled to the planetary gear 2; the planetary gear 2 is assembled to the planetary carrier 5 along the axial direction through the planetary shaft 4 to complete the installation of the planetary gear 2, the planetary shaft 4 and the planetary carrier 5, and this is carried out in sequence until all the planetary gears 2 and the planetary shaft 4 are assembled to the planetary carrier 5; then the planetary carrier 5 is assembled to the input shaft 1 to complete the assembly of the reducer.

[0070] In some embodiments of the present application, the first bearing structure is optimized. Specifically, Figure 2 and 4 As shown, the first bearing structure includes a retaining ring 8 fixed to the inner side of the planetary gear 2 and first bearings 9 disposed on both axial sides of the retaining ring 8 .

[0071] That is to say, in this embodiment, a planetary shaft 4, a snap ring 8 and two first bearings 9 are installed inside each planetary gear 2. The two first bearings 9 are placed on both sides of the axial direction of the snap ring 8. The snap ring 8 limits the contact between the two first bearings 9 to avoid interference between them. The first bearing 9 of this embodiment is preferably a tapered bearing, and of course other forms of bearing structures can also be used as long as they meet the requirements.

[0072] When assembling the planetary shaft 4, the first bearing 9, the snap ring 8 and the planetary gear 2, it is necessary to select the snap ring 8. The snap ring 8 has various specifications, that is, snap rings 8 of various thicknesses (referring to the thickness of the snap ring 8 in the axial direction). Select the snap ring 8 of appropriate thickness. The specific selection method is: record the installation width C1 corresponding to the planetary gear 2 on the planetary carrier 5, measure the axial widths of the two first bearings on both sides of the snap ring 8 in the axial direction of the first bearing as A1 and A2, and the optional thickness of the snap ring 8 is C1-A1-A2-a, where a is a set value, generally 0.01 mm, which is actually the allowable assembly tolerance.

[0073] In a further embodiment of the present application, the structure of the planet carrier 5 is optimized. Specifically, Figure 2 , 4 As shown in Figures 5 to 6, the planet carrier 5 is a hollow cavity structure, including a first side 51 close to the input shaft 1 and a second side 52 away from the input shaft 1. The first side 51 and the second side 52 are arranged at intervals along the axial direction, and mounting holes 53 corresponding to the planet shafts 4 are opened on the first side 51 and the second side 52. Both ends of the planet shaft 4 are passed through the mounting holes 53 to arrange the planetary gears 2 between the first side 51 and the second side 52.

[0074] The second side 52 is the power output end of the planet carrier 5, which is connected to the vehicle half shaft through a spline structure. The planet carrier 5 is a hollow structure, which is convenient for arranging structures such as the planetary gear 2 and the planetary shaft 4 in the planet carrier 5, making the arrangement of the components of the entire planetary gear more compact and occupying less space. At the same time, the hollow planet carrier 5 is also convenient for the flow of lubricating oil, and the lubricating oil can flow conveniently in the planet carrier 5, achieving the effect of wetting the bearing structure and making the rotation smoother.

[0075] A through hole for the input shaft 1 to pass through is provided in the axial middle position of the planet carrier 5 , and a through hole for the planet gear 2 to pass through is provided on the circumferential outer side of the planet carrier 5 , so that the rack structure of the planet gear 2 can pass through the planet carrier 5 and mesh with the rack structure on the ring gear 3 .

[0076] The planet carrier 5 is an integral structure with high strength, and is finely processed after forging or casting the shape, and has high dimensional accuracy. The existing planet carrier is usually processed in two halves, which are finely processed after being tightened or welded together by bolts, and the processing accuracy is low.

[0077] In a preferred embodiment of the present application, the oil flow structure of the above-mentioned reducer is optimized. Specifically, Figure 2 and 4 As shown, in this embodiment, an oil receiving pan 7 is provided in the shell 6. The oil receiving pan 7 is a hollow cavity structure fixed on the first side 51. An oil distribution structure is provided in the oil receiving pan 7. One end of the oil distribution structure is connected to the oil channel on the shell 6, and the other end axially passes through the first side 51 and penetrates into the interior of the planetary carrier 5.

[0078] That is to say, the oil pan 7 receives the oil sprayed from the housing 6, and then distributes it to the planet carrier 5 through the oil distribution structure. In order to more conveniently distribute the oil evenly to the structure in the planet carrier 5, it is actually mainly used to lubricate the first bearing structure. The planet shaft 4 of this embodiment is a hollow shaft-shaped structure with one side open, and the planet shaft 4 is provided with an oil outlet hole that radially connects the inner cavity of the planet shaft 4 and the outer first bearing 9.

[0079] The oil distribution structure on the oil receiving pan 7 includes a plurality of axial distribution pipes arranged on the side of the oil receiving pan 7 facing the planetary carrier 5. The axial distribution pipe is a hollow pipe parallel to the axis of the input shaft 1. One end of the axial distribution pipe is connected to the inner cavity of the oil receiving pan 7, and the other end is inserted into the planetary shaft 4 from the opening side of the planetary shaft 4 along the axial direction parallel to the input shaft 1. The oil entering the oil receiving pan 7 will be axially distributed to the planetary shaft 4 through the axial distribution pipe. The oil entering the planetary shaft 4 will be discharged to the outside of the planetary shaft 4 along the oil outlet hole on the planetary shaft 4 under the centrifugal effect, and enter the first bearing 9 on the outside to provide lubricating oil for the operation of the first bearing 9. The outlet end of the axial distribution pipe is spaced from the oil outlet hole in the axial direction, which can be set to 3mm to 5mm, that is, the axial distribution pipe does not overlap with the oil outlet hole in the axial direction. Such a setting facilitates the oil to enter the planetary shaft 4 from the axial distribution pipe, and the oil flows more smoothly in the planetary shaft 4, and the discharge from the oil outlet hole is more convenient, which has a better distribution effect on the oil.

[0080] At the same time, this embodiment also adjusts the position of the above-mentioned oil outlet hole. This embodiment designs the oil outlet hole between the two groups of first bearings 9, that is, the oil discharged from the oil outlet hole will be thrown between the two groups of first bearings 9 under the action of centrifugal force, and then distributed to both sides along the axial direction to achieve the effect of comprehensive lubrication of the first bearings 9.

[0081] In addition, a through hole 54 for discharging the oil in the planet carrier 5 is provided on the second side 52 of the planet carrier 5. A plurality of through holes 54 are provided on the second side 52, and the plurality of through holes 54 and the mounting holes 53 of the corresponding planet shafts 4 are evenly staggered around the axis of the input shaft 1. The through holes 54 facilitate the discharge of the oil in the planet carrier 5, so that the oil circulates in the entire reducer, reduces the resistance of the oil flowing in the planet carrier 5, and makes the oil flow smoother.

[0082] In other embodiments of the present application, the second bearing structure is optimized. Figure 2 and 4As shown, the second bearing structure of this embodiment includes a second bearing 10 and a third bearing 11 which are disposed on both axial sides of the planetary carrier 5 and correspond to the first side 51 and the second side 52 respectively. The second bearing 10 is fixed in the axial direction between the first side 51 and the input shaft 1 by a retaining ring, and the third bearing 11 is fixed in the axial direction between the second side 52 and the input shaft 1 by a retaining ring.

[0083] The second bearing 10 and the third bearing 11 are structures for supporting the planetary carrier 5, so that the connection between the planetary carrier 5 and the input shaft 1 is more stable, and the supporting stability and running smoothness are greatly improved.

[0084] Similarly, this embodiment optimizes the design for lubrication of the second bearing 10 and the third bearing 11 , and an oil outlet for spraying oil to the second bearing 10 is provided on the housing 6 , that is, there are two oil outlets on the housing 6 , one corresponding to the oil receiving pan 7 , and the other corresponding to the second bearing 10 .

[0085] The oil corresponding to the third bearing 11 is actually part of the oil flowing out from the hole corresponding to the input shaft 1 on the second side 52. This part of the oil flows through the third bearing 11 to lubricate the third bearing 11. The outflowing oil flows back to the oil pan in the reducer through the flow channel on the input shaft 1, and is then transferred to the housing 6 through the oil pump to complete the circulation flow.

[0086] There is also a connection relationship between the housing 6 and the planet carrier 5, such as Figure 2 and 4 As shown, the planet carrier 5 further includes a fourth bearing 12 located on the side away from the input shaft 1. In order to facilitate lubrication of the fourth bearing 12, the housing 6 is provided with an oil outlet for spraying oil to the fourth bearing 12. That is, two oil paths are also provided on the housing 6 on the side facing away from the oil receiving pan 7, one corresponding to the second side 52, and the other corresponding to the fourth bearing 12. The oil path spraying to the second side 52 can allow the oil to enter the planet carrier 5 through the through hole 54 on the second side 52.

[0087] During actual assembly: select the corresponding snap ring 8 based on the axial width of the first bearing structure and the installation width of the planet carrier 5, record the installation width C1 of the corresponding planet gear 2 on the planet carrier 5, measure the axial widths of the two first bearings on both sides of the snap ring 8 in the first bearing as A1 and A2, and the thickness of the snap ring 8 can be selected as C1-A1-A2-a; assemble the selected snap ring 8 to the planet gear 2, and then assemble the two first bearings 9 into the planet gear 2 from both sides of the snap ring 8; assemble the planet gear 2 equipped with the first bearings 9 Put it into the planet carrier 5, make the inner ring of the first bearing 9, the planetary gear 2 and the corresponding mounting hole 53 on the planet carrier 5 coaxial, insert the guide pin into the mounting hole 53 and the inner ring of the first bearing 9, and then press the planetary shaft 4 to be assembled into the mounting hole 53 of the planet carrier 5 axially with interference fit until the guide pin is completely expelled, and the installation of the planetary shaft 4, planetary gear 2 and planet carrier 5 is completed; proceed in sequence until all the planetary gears 2 and planetary shafts 4 are assembled to the planet carrier 5; then assemble the planetary carrier 5 to the input shaft 1 to complete the assembly of the reducer.

[0088] In actual application, the oil pump pumps the lubricating oil in the oil pan in the reducer into the housing 6, and the oil pump divides the oil into two parts, one part enters the housing 6 close to the oil receiving pan 7, and the other part enters the housing 6 far away from the oil receiving pan 7; the oil entering the housing 6 close to the oil receiving pan 7 is divided into two parts, one part enters the oil receiving pan 7, flows in the oil receiving pan 7 and enters the axial distribution pipe, and then the oil is distributed to the planetary shaft 4 under the action of the axial distribution pipe. In the process of the planetary shaft 4 following the rotation of the planetary gear 2, the oil is thrown to the first bearing 9 through the oil outlet hole under the action of centrifugation, and the oil flows evenly in the planetary carrier 5, and the other part is directly sprayed to the second bearing 10;

[0089] The oil entering the housing 6 away from the oil receiving pan 7 is divided into two parts. One part directly enters the planet carrier 5 through the through hole 54 on the second side 52 and flows evenly in the planet carrier 5. The other part is directly sprayed to the fourth bearing 12 to lubricate the fourth bearing 12.

[0090] The oil entering the planetary carrier 5 is eventually discharged from the third bearing 11 to the outside of the planetary carrier 5, enters the input shaft 1, and finally flows out from the side close to the oil receiving pan 7, and finally flows back to the oil pan, forming a cycle.

[0091] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application to be protected. The scope of protection claimed in the present application is defined by the attached claims and their equivalents.

Claims

1. A planetary gear reducer for coaxial distributed drive, characterized in that: include, Housing (6); An input shaft (1), one end of the input shaft (1) being connected to a power output device; A plurality of planetary gears (2), the plurality of planetary gears (2) being arranged at intervals along the circumference of the input shaft (1) with the axis of the input shaft (1) as the center, the planetary gears (2) being meshingly connected to the input shaft (1) and driven by the input shaft (1) to revolve around the axis of the input shaft (1); A gear ring (3), the outer side of the gear ring (3) is fixed to the housing (6), and the inner side is meshed with the planetary gear (2); A plurality of planetary shafts (4), one end of each planetary shaft (4) is arranged along an axis parallel to the input shaft (1) and penetrates the planetary gear (2), and is connected to the planetary gear (2) via a first bearing structure so as to be rotatable around its own axis, and the planetary shaft (4) and the planetary gear (2) are arranged coaxially; A planet carrier (5), wherein the planet carrier (5) is sleeved on the input shaft (1) and can rotate around the axis of the input shaft (1) via a second bearing structure, and the planet carrier (5) and the other end of the planet shaft (4) are fixedly connected in a direction of rotation around the axis of the input shaft (1); The revolution axis of the planetary gear (2), the rotation axis of the planet carrier (5) and the axis of the input shaft (1) coincide with each other.

2. A planetary gear reducer for coaxial distributed drive according to claim 1, characterized in that: The planet carrier (5) is a hollow cavity structure, comprising a first side (51) close to the input shaft (1) and a second side (52) away from the input shaft (1); the first side (51) and the second side (52) are arranged at intervals along the axial direction, and mounting holes (53) corresponding to the planet shafts (4) are opened on the first side (51) and the second side (52); both ends of the planet shaft (4) are passed through the mounting holes (53) to arrange the planet gears (2) between the first side (51) and the second side (52).

3. A planetary gear reducer for coaxial distributed drive according to claim 2, characterized in that: An oil receiving pan (7) is arranged in the shell (6); the oil receiving pan (7) is a hollow cavity structure fixed to the first side (51), and an oil distribution structure is arranged in the oil receiving pan (7); one end of the oil distribution structure is connected to the oil channel on the shell (6), and the other end axially passes through the first side (51) and penetrates into the interior of the planet carrier (5).

4. A planetary gear reducer for coaxial distributed drive according to claim 3, characterized in that: The second side (52) is provided with a through hole (54) for discharging oil in the planet carrier (5).

5. A planetary gear reducer for coaxial distributed drive according to claim 4, characterized in that: A plurality of through holes (54) are provided on the second side (52), and the plurality of through holes (54) and the mounting holes (53) of the corresponding planetary shafts (4) are evenly staggered and arranged with the axis of the input shaft (1) as the center.

6. A planetary gear reducer for coaxial distributed drive according to claim 1, characterized in that: The first bearing structure comprises a retaining ring (8) fixed to the inner side of the planetary gear and first bearings (9) disposed on both axial sides of the retaining ring (8).

7. A planetary gear reducer for coaxial distributed drive according to claim 6, characterized in that: The planetary shaft (4) is a hollow shaft-shaped structure with one side open, and the planetary shaft (4) is provided with an oil outlet hole which radially connects the inner cavity of the planetary shaft (4) and the outer first bearing (9).

8. A planetary gear reducer for coaxial distributed drive according to claim 2, characterized in that: The second bearing structure comprises a second bearing (10) and a third bearing (11) which are arranged on both axial sides of the planet carrier (5) and correspond to the first side (51) and the second side (52) respectively; the second bearing (10) is fixed in the axial direction between the first side (51) and the input shaft (1) through a retaining ring; and the third bearing (11) is fixed in the axial direction between the second side (52) and the input shaft (1) through a retaining ring.

9. A planetary gear reducer for coaxial distributed drive according to claim 8, characterized in that: The housing (6) is provided with an oil outlet for spraying oil toward the second bearing (10).

10. A planetary gear reducer for coaxial distributed drive according to claim 8, characterized in that: The third bearing (11) is located at an oil outlet position on the planet carrier (5).

11. The planetary gear reducer for coaxial distributed drive according to claim 1, characterized in that: It also includes a fourth bearing (12) located on the side of the planet carrier (5) away from the input shaft (1); and the housing (6) is provided with an oil outlet for spraying oil toward the fourth bearing (12).

12. A method for assembling a planetary gear reducer for coaxial distributed drive, characterized in that: The assembly method is used to assemble any one of the planetary gear reducers for coaxial distributed drive as claimed in claims 1 to 11. include, Selecting a corresponding snap ring (8) based on the axial width of the first bearing structure and the installation width of the planet carrier (5); Assembling the selected snap ring (8) onto the planetary gear (2), and then assembling the first bearing structure onto the planetary gear (2); Passing the planetary shaft (4) axially to assemble the planetary gear (2) onto the planetary carrier (5), completing the installation of the planetary gear (2), the planetary shaft (4) and the planetary carrier (5), and proceeding in sequence until all the planetary gears (2) and the planetary shaft (4) are assembled onto the planetary carrier (5); Then assemble the planet carrier (5) onto the input shaft (1) to complete the assembly of the reducer.

13. The method for assembling a planetary gear reducer for coaxial distributed drive according to claim 12, characterized in that: The method for selecting a corresponding retaining ring (8) based on the axial width of the first bearing structure and the installation width of the planet carrier (5) comprises: recording the installation width C1 of the corresponding planetary gear (2) on the planet carrier (5), measuring the axial widths of two first bearings on both sides of the axial direction of the retaining ring (8) in the first bearing as A1 and A2, and the thickness of the retaining ring (8) can be selected as C1-A1-A2-a, where a is a set value.

14. The method for assembling a planetary gear reducer for coaxial distributed drive according to claim 12, characterized in that: The method for assembling a planetary gear (2) onto a planetary carrier (5) by axially passing through a planetary shaft (4) comprises: placing a planetary gear (2) equipped with a first bearing structure into the planetary carrier (5), making the inner ring of the first bearing structure, the planetary gear (2) and the corresponding mounting hole (53) on the planetary carrier (5) coaxial, inserting a guide pin into the mounting hole (53) and the inner ring of the first bearing structure; and then inserting the planetary shaft (4) to be assembled into the mounting hole (53) of the planetary carrier (5) in an interference fit manner along the axial direction until the guide pin is completely ejected, thereby completing the installation of the planetary shaft (4), the planetary gear (2) and the planetary carrier (5).

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