Planet carrier assembly, planetary reducer, planetary reducer assembly and anti-backlash installation method

Abstract

The invention discloses a planet carrier assembly, a planetary reducer, an assembly of the planetary reducer and an anti-backlash installation method.The planet carrier assembly comprises a first frame and a second frame located in the first frame, and a planet wheel is fixed to the second frame through a bearing; the two end faces of the second frame and the two end faces, close to the second frame, of the first frame are fixedly installed in a matched mode through fasteners, at least part of a frame body of the second frame is of an elastic structure and / or a split structure so that the frame body can generate elastic deformation, and in the expansion process of the second frame, the first planet gear and the fixed gear ring can be meshed more tightly. Before a sun gear is installed on the planetary reducer, an expansion tool is used for expanding the pitch diameter of the axis of a planet gear on a second frame and reducing the meshing gap between a fixed gear ring and a first planet gear, and when the fixed gear ring is tightly meshed with the first planet gear, a second bolt is screwed, so that the adjacent end faces of the first frame and the second frame are in contact; and then the expansion tool is taken out, and then other assemblies are installed.

Description

Technical Field

[0001] The invention belongs to a planetary transmission device, and in particular relates to a planetary carrier assembly, a planetary reducer assembly that can be installed by a backlash-eliminating method, a planetary reducer, and a backlash-eliminating installation method. Background Art

[0002] As electronic devices in fields such as robots and medical equipment become more and more sophisticated, existing technologies are placing higher and higher demands on reducers.

[0003] In the prior art, the NW type planetary gear train uses a double gear, in which the large gear meshes with the sun gear externally to obtain a certain transmission ratio i1, and then converts to a small gear meshing with the inner ring gear to obtain a certain transmission ratio i2; the final gear transmission ratio is i1xi2.

[0004] Traditional planetary transmissions have problems such as low transmission accuracy, large side clearance, etc. due to gear processing errors and assembly errors.

[0005] CN113757349A discloses a planetary transmission device with a variable position planetary carrier system, which uses an expansion sleeve flexible planetary carrier to continuously adjust the center distance between the planetary gear and the inner gear ring to reduce the gap. In order to further reduce the number of parts for planetary carrier adjustment and reduce the initial gap of the assembly, a high-precision transmission device is provided. Summary of the invention

[0006] The purpose of the present invention is to provide a planetary carrier assembly, a planetary reducer assembly that can be installed by a clearance elimination method, a planetary reducer, and a clearance elimination installation method. The planetary carrier assembly adopts a structure that combines an outer rigid frame and an inner flexible frame, and can be installed by a clearance elimination method; during assembly, the second frame is first installed in the first frame with a gap through the use of an expansion tool and a fastener, and after the pitch diameter of the planetary wheel axis on the second frame is expanded, the planetary gear is better moved in the radial direction to closely mesh with the gear ring, and then the relative position of the first frame and the second frame is fixed by fasteners, and then the expansion tool is removed to achieve clearance elimination installation.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] The first aspect of the present invention discloses a planetary carrier assembly, including a first frame and a second frame located inside the first frame, the planetary gears are fixed to the second frame through bearings, the two end faces of the second frame and the two end faces of the first frame close thereto are respectively mounted and fixed by fasteners, at least part of the frame of the second frame is an elastic structure and / or a split structure, and can change the position of the planetary shaft under the action of external force before being fastened to the first frame. In the present invention, the planetary carrier assembly mainly changes the radial position of the planetary shaft, eliminating the gap between the planetary gear and the gear ring; at the same time, in the process of changing the radial position, the circumferential position can also be changed under the constraint of the gear meshing, overcoming the processing error of the planetary carrier shaft hole, making the meshing of the planetary gear and the gear ring more perfect.

[0009] The second aspect of the present invention discloses a planetary reducer assembly of planetary wheels and gear rings that can be installed by a clearance-eliminating method, comprising a fixed gear ring, a roller, a first planetary wheel and the above-mentioned planetary frame assembly; the frame body of the second frame is provided with alternating notches or the frame body of the second frame is radially cut at at least two locations to form a split structure, so that it can deform, and during the expansion process of the second frame, the first planetary wheel and the fixed gear ring are more closely engaged; the first frame is rotatably arranged in the fixed gear ring, and forms a slewing bearing with the fixed gear ring through rollers.

[0010] The third aspect of the present invention discloses a planetary reducer, which includes the planetary reducer assembly of the above-mentioned planetary wheels and ring gears that can be installed by the anti-backlash method, and also includes a sun wheel and a second planetary wheel; the sun wheel is used for input, and the planetary frame assembly is used for output; when working, the sun wheel drives the second planetary wheel, the second planetary wheel drives the first planetary wheel to roll and mesh with the fixed ring gear, and the first planetary wheel drives the second frame to rotate through rollers, and the two end faces of the second frame are respectively fastened with bolts on the two end faces of the first frame close to it, and the first upper frame of the first frame rotates as the output end to reduce speed.

[0011] Furthermore, when the planetary reducer with the second planetary gear is working, the sun gear drives the second planetary gear, the second planetary gear drives the first planetary gear to roll and engage with the fixed ring gear, the first planetary gear drives the second frame to rotate through a needle bearing, the two end faces of the second frame are respectively fastened with bolts on the two end faces of the first frame close to it, and the first upper frame of the first frame rotates as the output end to reduce speed.

[0012] In one embodiment, the planetary reducer includes, in addition to the second planetary gear, a sun gear driving gear and an offset input gear. The sun gear driving gear is coaxially fixed with the sun gear, and the sun gear driving gear is meshed with the offset input gear.

[0013] Preferably, when the pitch diameter is expanded using an expansion tool, the fixed ring gear and the first planetary gear are meshed without gap.

[0014] The fourth aspect of the present invention discloses a planetary reducer, which includes a planetary reducer assembly of the above-mentioned planetary wheels and ring gears that can be installed by the anti-backlash method, and also includes a sun wheel. When the planetary reducer assembly is working, the sun wheel is used for input and the planetary frame assembly is used for output; the sun wheel drives the first planetary wheel, the first planetary wheel is rollingly engaged with the fixed ring gear, and the first planetary wheel drives the second frame to rotate through a roller, and the two end faces of the second frame are respectively fastened with bolts on the two end faces of the first frame close to it, and the first upper frame of the first frame rotates as the output end to reduce speed.

[0015] Furthermore, when the planetary reducer is working, the sun gear drives the first planetary gear, the first planetary gear is rollingly engaged with the fixed ring gear, and the first planetary gear drives the second frame to rotate through a needle bearing, the two end faces of the second frame are respectively fastened with bolts on the two end faces of the first frame close to it, and the first upper frame of the first frame rotates as the output end to reduce speed.

[0016] Furthermore, in one embodiment, the planetary reducer also includes a front-stage planetary reducer assembly, which includes a second fixed ring gear, a second planetary carrier, a front-stage planetary wheel and a second sun wheel. The second fixed ring gear and the first lower frame are fixedly connected by bolts, the second planetary carrier is connected to the sun wheel by a spline fit, and the second sun wheel drives the sun wheel to rotate by driving the second planetary carrier.

[0017] In one embodiment, an expansion tool is inserted into the corresponding axial holes of the first frame and the second frame, and the wall of the axial hole is squeezed by expanding the outer diameter of the expansion tool to expand the pitch diameter of the planetary gear axis on the second frame with a notch. During the expansion of the planetary carrier, the center distance between the planetary gear and the ring gear becomes larger, and the meshing becomes tighter.

[0018] In one embodiment, when the anti-backlash installation method is used for installation, the radius expansion required when using the expansion tool to expand the second frame does not exceed half of the tooth height of the planetary gear, so the expansion tool does not need a large adjustment stroke. When the accuracy level of each part of the planetary transmission device is high, it is only necessary to process the second upper frame body and the second lower frame body of the second frame to form notches that can meet the small elastic deformation amount.

[0019] Preferably, the first frame is a rigid frame, comprising a first upper frame body and a first lower frame body, the first upper frame body and the first lower frame body are fastened together by bolts, and the space inside the first upper frame body and the first lower frame body is used to accommodate the first planetary gear and the second frame;

[0020] The second frame is a flexible frame, including a second upper frame body and a second lower frame body, and the second upper frame body and the second lower frame body are provided with notches in the form of grooves, which are used to elastically deform the second upper frame body and the second lower frame body, and can elastically lengthen the pitch diameters of the axles of the planetary gears on the second upper frame body and the second lower frame body;

[0021] Furthermore, an axial hole is provided at a corresponding position in the middle of the first frame and the second frame for inserting a sun gear or an expansion tool.

[0022] In another embodiment, the second frame is a flexible frame, including a second upper frame body and a second lower frame body, and the second upper frame body and the second lower frame body are cut at least two places along the radial direction of the frame body to form a split structure, which is used to deform the second upper frame body and the second lower frame body (5) and can elastically lengthen the pitch diameter of the planetary gear axis on the second upper frame body and the second lower frame body.

[0023] Furthermore, the first upper frame and the first lower frame have corresponding first holes in their positions, which are fixedly connected to the first upper frame and the first lower frame by a first bolt; the first upper frame and the second upper frame / the first lower frame and the second lower frame have corresponding second holes in their positions, which are fixedly connected to the first upper frame and the second upper frame / the first lower frame and the second lower frame by a second bolt, respectively, and the second hole on the first frame is slightly larger than the diameter of the bolt, so that the second frame can be adapted to the second hole on it after it is opened.

[0024] Specifically, a plurality of second through holes are provided on the first upper frame and the first lower frame, and a plurality of second threaded holes are provided on the second upper frame and the second lower frame; the first through hole is provided on the first upper frame, and the first threaded hole corresponding to the position of the first through hole is provided on the first lower frame; wherein, the first bolt passes through the first through hole of the first upper frame and the first threaded hole of the first lower frame in sequence, and is used to fix the first upper frame and the first lower frame by bolts, and the second bolt is used to pass through the second through hole of the first upper frame and the second threaded hole of the second upper frame or pass through the second through hole of the first lower frame and the second threaded hole of the second lower frame in sequence, and is used to thread the first upper frame and the second upper frame / the first lower frame and the second lower frame, and the second through hole of the first upper frame is slightly larger than the diameter of the bolt, so that the second frame can adapt to the second threaded hole thereon after it is opened.

[0025] Preferably, the first lower frame includes an annular body and a support column, a plurality of clearance holes are provided on the annular body, and the support column and the clearance holes are arranged at intervals; the second upper frame and the second lower frame include an annular structure and three bosses extending radially along the outer wall of the annular structure, a through hole is provided on each boss as a planetary shaft hole, and the first planetary gear is fixed to the second frame through a bearing.

[0026] Furthermore, the bosses of the second upper frame and the second lower frame correspond to each other, and the bosses of the second upper frame and the second lower frame are located exactly between the adjacent support columns of the first lower frame; and the outer contour gap of the boss is adapted to the clearance hole.

[0027] Preferably, a pair of staggered notches along the radial direction of the second upper frame are respectively processed on the side walls of the annular structure where no boss is provided, and the two staggered notches are in opposite directions, and the depth of each pair of staggered notches is greater than the axial wall thickness before the processed notch at the notch position of the second upper frame.

[0028] Preferably, the side wall of the annular structure where no boss is provided is cut at two or more locations along the radial direction of the second upper frame body, so that the second frame body forms a split structure.

[0029] A third aspect of the present invention also includes a backlash-eliminating installation method for the planetary reducer assembly, comprising:

[0030] Before installing the sun gear, the planetary reducer assembly first uses a first bolt to fasten the first frame, and uses a second bolt to connect the second frame, and the second bolt is in a loose and untightened state, and the second frame is installed in the first frame with a gap;

[0031] Using an expansion tool to expand the pitch diameter of the axis of the planetary gear on the second frame, and reduce the meshing clearance between the fixed gear ring and the first planetary gear;

[0032] When the fixed gear ring and the first planetary gear are tightly meshed, the second bolt is tightened to make the adjacent end faces of the first frame and the second frame contact, and then the expansion tool is taken out and the remaining components are installed.

[0033] The expansion tool may be an expansion sleeve adapted to the second hole of the second frame, more preferably, a hydraulic expansion sleeve, a pneumatic expansion sleeve or a mechanical expansion sleeve.

[0034] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0035] The planetary reducer of the present invention can expand the circumference of the planet carrier during installation, increase the orbital radius of the planetary gear, make the planetary gear close to the inner gear ring, compress the side clearance between the planetary gear and the inner gear ring, and reduce the backlash of the planetary transmission;

[0036] At the same time, the expansion tool for expanding the planetary frame is only used during installation, and the planetary reducer itself does not add any expansion device, which is beneficial to reducing the complexity of the reducer structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is an exploded view of the planet carrier assembly shown in Example 1;

[0038] Figure 2 for Figure 1 a cross-sectional view of the planet carrier assembly shown;

[0039] Figure 3 It is a cross-sectional view of the NW type planetary reducer shown in Example 2;

[0040] Figure 4 for Figure 3 The exploded view of the NW type planetary reducer shown;

[0041] Figure 5 It is an exploded view of the NW type planetary reducer shown in Example 3;

[0042] Figure 6 yes Figure 5 The cross-sectional view of the NW type planetary reducer shown;

[0043] Figure 7 is an exploded view of the NGW type planetary reducer shown in Example 4;

[0044] Figure 8 yes Figure 7 The exploded view of the NGW type planetary reducer shown;

[0045] Fig. 9 It is an exploded view of the NGW type planetary reducer shown in Example 5;

[0046] Fig.10 yes Fig. 9 The cross-sectional view of the NGW type planetary reducer is shown.

[0047] In the figure:

[0048] 1: Fixed gear ring, 2: First upper frame, 3: First lower frame, 4: Second upper frame, 5: Second lower frame,

[0049] 6: first planetary gear, 7: second planetary gear, 8: sun gear, 9: planetary shaft, 10: shaft hole;

[0050] 11: sun gear drive gear, 12: offset input gear, 13: first through hole, 13a: first threaded hole,

[0051] 14: second through hole, 14a: second threaded hole, 15: staggered notch, 16: support column, 17: first bolt,

[0052] 18: Second bolt, 19: Clearance hole, 20: Needle roller bearing, 21: Oil seal, 23: Second fixed gear ring,

[0053] 24: Second planet carrier, 25: Second sun gear, 26: Front stage planet gear. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution, beneficial effects and significant progress of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described below in conjunction with the drawings provided in the examples of the present invention. Obviously, all the described embodiments are only partial embodiments of the present invention, rather than all embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0055] Example 1

[0056] like Figure 1-2 As shown, a planet carrier assembly that can be installed by an anti-backlash method includes a planet carrier assembly and first planetary gears 6. Three first planetary gears 6 are arranged in the planet carrier assembly through planetary shafts 9.

[0057] The planetary frame assembly is a structure in which two frames are sleeved from the outside to the inside, including a first frame and a second frame, the first frame is a rigid frame, the second frame is a flexible frame, the first frame and the second frame are coaxially arranged, and a certain distance is maintained between the two. The first frame includes a first annular upper frame body 2 and a first lower frame body 3, the first upper frame body 2 is an annular structure, a plurality of second through holes 14 are provided on the first upper frame body 2 and the first lower frame body 3, a first through hole 13 is provided on the first upper frame body 2, and a first threaded hole 13a corresponding to the position of the first through hole 13 is provided on the first lower frame body 3, and a first bolt 17 passes through the first through hole 13 of the first upper frame body 2 and the first threaded hole 13 of the first lower frame body 3 in sequence, and is used to fix the first upper frame body 2 and the first lower frame body 3 by bolts, and the space inside the first upper frame body 2 and the first lower frame body 3 is used to accommodate the planetary shaft 9, the first planetary gear 6 and the second frame. Furthermore, corresponding positions in the middle of the first upper frame 2, the second upper frame 4, the second lower frame 5 and the first lower frame 3 are all provided with an axial hole 10 for inserting the sun gear 8 or an expansion tool.

[0058] The first lower frame 3 includes an annular body and a support column 16, the support column 16 is arranged on the surface of the first lower frame 3 facing the first upper frame 2, and a clearance hole 19 and a second through hole 14 are provided on the annular body of the first lower frame 3, and the support column 16 and the clearance hole 19 are arranged at intervals. The top of the support column 16 has a first threaded hole 13a, which is used to fix the first lower frame 3 and the bottom surface of the first upper frame 2 through a first bolt 17. The first through hole 13 and the second through hole 14 on the first lower frame 3 are both through holes. Roller raceways are provided at the positions of the first upper frame 2 and the first lower frame 3 opposite to the fixed gear ring 1. The second frame includes a second upper frame 4 and a second lower frame 5, and a plurality of second threaded holes 14a are provided on the second upper frame 4 and the second lower frame 5, and the positions and sizes of the second threaded holes 14a on the second upper frame 4 and the second lower frame 5 correspond to the second through holes 14 of the first frame. The second upper frame 4 includes an integrally formed annular structure and three bosses extending radially uniformly along the outer wall of the annular structure. A through hole is arranged on each boss as a planetary shaft hole, in which a planetary shaft 9 is arranged. A first planetary gear 6 is arranged on the outer wall of the planetary shaft 9, and the first planetary gear 6 is fixed to the second frame through a bearing.

[0059] A pair of staggered notches 15 are processed along the axial direction of the second upper frame body 4 on the side wall of the annular structure where no boss is provided, and the two staggered notches are in opposite directions, and the depth of each pair of staggered notches is greater than the axial wall thickness before the processed notches at the notch position of the second upper frame body 4; the notches 15 are in the form of grooves. The purpose of providing the notches is to cause a slight elastic deformation of the second upper frame body 4, and elastically lengthen the pitch diameter of the axis of the planetary gear on the second upper frame body 4.

[0060] In addition to the above description, the notch 15 can also be processed in the radial direction. There are various structures that can cause the second upper frame body 4 to undergo slight elastic deformation. The above are only illustrative examples, but the essence is to lengthen the pitch diameter of the axis of the planetary gear on the frame body. For this purpose, various styles of notches that can be elongated can be processed. In addition, the distribution of the notches that can be elongated is preferably staggered with the distribution of the bosses with the planetary shaft holes, which is conducive to the uniform lengthening of the distance between the planetary gears. During the expansion of the planetary frame, the planetary gears can move better in the radial direction without changing the distribution phase of the planetary gears.

[0061] The structure of the second lower frame 5 is the same as that of the second upper frame 4 or is arranged in a horizontal mirror image, and will not be described in detail here.

[0062] During installation, the bosses of the second upper frame 4 and the second lower frame 5 correspond to each other, and the bosses of the second upper frame 4 and the second lower frame 5 are located exactly between the adjacent support columns 16 of the first lower frame 3; and the outer contour of the boss fits the space between two adjacent support columns.

[0063] When the planet carrier assembly described in this embodiment is installed in the fixed gear ring, the installation method of the planet carrier assembly that can be installed by the clearance elimination method includes:

[0064] Step 1: Before installing the sun gear, first place the second upper frame 4 and the second lower frame 5 into the first frame to form a second frame (the second upper frame 4 and the second lower frame 5 are not fixed at this time), assemble the first upper frame 2 and the first lower frame 3, and the first planetary gear 6 is arranged on the outer wall of the planetary shaft, and the planetary shaft is arranged in the first frame and the second frame;

[0065] Then, the first bolt 17 is screwed into the first through hole 13 of the first upper frame 2 and the first threaded hole 13 of the first lower frame 3 in sequence and tightened, thereby fixing the first upper frame 2 and the first lower frame 3, thereby fixing the first upper frame and the first lower frame to form a fastened first frame;

[0066] Use the second bolt 18 to screw into the second through hole 14 of the first upper frame 2 and the second threaded hole 14a of the second upper frame 4 in sequence, and screw into the second through hole 14 of the first lower frame 3 and the second threaded hole 14a of the second lower frame 5 in sequence, and keep the second bolt 18 in a loose and untightened state;

[0067] At this time, the fixed ring gear 1 and the first planetary gear 6 are in meshing with a gap, there is a gap between the bottom surface of the first upper frame 2 and the top surface of the second upper frame 4 (i.e., adjacent end surfaces), and there is a gap between the top surface of the first lower frame 3 and the bottom surface of the second lower frame 5.

[0068] Step 2: Use an expansion tool to sequentially pass through the first upper frame 2, the second upper frame 4, the second lower frame 5 and the axial hole 10 in the middle of the first lower frame 3, expand the outer diameter of the expansion tool so that the outer diameter of the expansion tool squeezes the wall surface of the axial hole of the frame in contact with it, and use the expansion tool to expand the second upper frame 4 and the second lower frame 5 with a notch 15, so as to elastically lengthen the pitch diameter of the axle center of the planetary gear on the second upper frame 4 and the second lower frame 5. During the expansion process of the planetary frame, the center distance between the planetary gear and the gear ring becomes larger, and the meshing becomes tighter. Among them, the present invention does not limit the expansion tool, as long as it can expand the pitch diameter of the axle center of the planetary gear on the second frame, the hardness of the expansion tool material is not less than the hardness of the second upper frame 4 and the second lower frame 5 material, and the outer wall profile of the expansion tool is preferably slightly smaller than the aperture of the axial hole.

[0069] Step three: When the fixed gear ring 1 and the first planetary gear 6 are meshed without gap, tighten the second bolt 18 to make the adjacent end faces of the first frame and the second frame contact, and then remove the expansion tool; then install the sun gear 8 at the axial holes of the first upper frame 2, the second upper frame 4, the second lower frame 5 and the first lower frame 3, so that the sun gear 8 is meshed with the first planetary gear 6.

[0070] Example 2

[0071] like Figure 3-4 As shown, a NW type planetary reducer that can be installed by a backlash elimination method comprises a fixed ring gear 1, a sun gear 8, a planet carrier assembly, a first planetary gear 6 and a second planetary gear 7. A planet carrier assembly is arranged in the fixed ring gear 1, the planet carrier assembly is connected to the output shaft and is rotatably arranged in the fixed ring gear; three first planetary gears 6 are arranged on the planet carrier assembly through planetary shafts 9, and three second planetary gears 7 are located on one side of the planet carrier assembly close to the output shaft; the sun gear 8 is connected to the input shaft, and the sun gear 8 is meshed with the second planetary gear 7.

[0072] The planetary frame assembly is a structure in which two frames are sleeved from the outside to the inside, including a first frame and a second frame. The structure of the first frame and the second frame is basically the same as that of Example 1, and the same structure will not be repeated here. Only the differences are described below.

[0073] The surfaces of the first upper frame 2 facing the fixed gear ring 1 are all inclined surfaces, the inclined surface on the fixed gear ring 1 serves as the fixed end guide surface, the surface of the first upper frame 2 serves as the output end guide surface, and a needle bearing 20 is arranged between the fixed end guide surface and the output end guide surface, so that the two guide surfaces can slide relative to each other. Similarly, the surfaces of the first lower frame 3 facing the fixed gear ring 1 are all inclined surfaces, the inclined surface on the fixed gear ring 1 serves as the fixed end guide surface, and the surface of the first lower frame 3 serves as the output end guide surface, and a needle bearing 20 is arranged between the fixed end guide surface and the output end guide surface, so that the two guide surfaces can slide relative to each other.

[0074] An oil seal 21 is provided between the outer wall of the first upper frame 2 and the inner wall of the fixed gear ring 1 to enhance the sealing performance.

[0075] When the planetary reducer is running, the sun gear 8 drives the second planetary gear 7, and the second planetary gear 7 drives the first planetary gear 6 to roll and engage with the fixed ring gear 1. The first planetary gear 6 drives the second upper frame 4 and the second lower frame 5 to rotate through the needle bearing 20. Since the second upper frame 4 and the second lower frame 5 are fixedly connected to the first upper frame 2 and the first lower frame 3 respectively by bolts, the first upper frame 2 rotates as the output end with a reduction in speed.

[0076] The installation method of the planetary reducer that can be installed by the anti-backlash method includes:

[0077] Step 1: Before installing the sun gear, first place the second upper frame 4 and the second lower frame 5 into the first frame to form a second frame (the second upper frame 4 and the second lower frame 5 are not fixed at this time), assemble the first upper frame 2 and the first lower frame 3, and the first planetary gear 6 is arranged on the outer wall of the planetary shaft, and the planetary shaft is arranged in the first frame and the second frame;

[0078] Then, the first bolt 17 is screwed into the first through hole 13 of the first upper frame 2 and the first threaded hole 13 of the first lower frame 3 in sequence and tightened, thereby fixing the first upper frame and the first lower frame 3 to form a fastened first frame;

[0079] Use the second bolt 18 to screw into the second through hole 14 of the first upper frame 2 and the second threaded hole 14a of the second upper frame 4 in sequence, and screw into the second through hole 14 of the first lower frame 3 and the second threaded hole 14a of the second lower frame 5 in sequence, and keep the second bolt 18 in a loose and untightened state;

[0080] At this time, the fixed ring gear 1 and the first planetary gear 6 are in meshing with a gap, there is a gap between the bottom surface of the first upper frame 2 and the top surface of the second upper frame 4 (i.e., adjacent end surfaces), and there is a gap between the top surface of the first lower frame 3 and the bottom surface of the second lower frame 5.

[0081] Step 2: Use an expansion tool to sequentially pass through the first upper frame 2, the second upper frame 4, the second lower frame 5 and the axial hole 10 in the middle of the first lower frame 3, expand the outer diameter of the expansion tool so that the outer diameter of the expansion tool squeezes the wall surface of the axial hole of the frame in contact with it, and use the expansion tool to expand the second upper frame 4 and the second lower frame 5 with a notch 15, so as to elastically lengthen the pitch diameter of the axis of the planetary gear on the second upper frame 4 and the second lower frame 5. During the expansion process of the planetary frame, the center distance between the planetary gear and the gear ring becomes larger, and the meshing becomes tighter. Among them, the hardness of the material of the expansion tool is not less than the hardness of the material of the second upper frame 4 and the second lower frame 5, and the outer wall profile of the expansion tool is preferably slightly smaller than the aperture of the axial hole.

[0082] Step three: When the fixed gear ring 1 and the first planetary gear 6 are tightly engaged (it can be a gapless engagement or adjusted to a smaller gap than in step two), tighten the second bolt 18 to make the adjacent end faces of the first frame and the second frame contact, and then remove the expansion tool; then install the sun gear 8 at the axial holes of the first upper frame 2, the second upper frame 4, the second lower frame 5 and the first lower frame 3, so that the sun gear 8 is engaged with the second planetary gear 7.

[0083] Example 3

[0084] like Figure 5-6As shown, a NW type planetary reducer that can be installed by the anti-backlash method, the NW type planetary reducer is basically the same as Example 2, the same content will not be repeated, and only the differences are described below.

[0085] The NW type planetary reducer comprises a fixed gear ring 1, a sun gear 8, a planetary carrier assembly, a first planetary gear 6 and a second planetary gear 7. A planetary carrier assembly is arranged inside the fixed gear ring 1, the planetary carrier assembly is connected to the output shaft and is rotatably arranged inside the fixed gear ring; three first planetary gears 6 are arranged on the planetary carrier assembly through planetary shafts 9; three second planetary gears 7 are located on one side of the planetary carrier assembly close to the output shaft, the sun gear 8 is connected to the input shaft, and the sun gear 8 is meshed with the second planetary gears 7; the sun gear driving gear 11 is tightly fitted on the outer wall of the sun gear, and the sun gear driving gear 11 is meshed with the offset input gear 12.

[0086] When the planetary reducer is running, the offset input gear 12 drives the sun gear driving gear 11 to rotate, thereby driving the sun gear 8 to rotate, the sun gear 8 drives the second planetary gear 7, the second planetary gear 7 drives the first planetary gear 6 to roll and mesh with the fixed ring gear 1, and the first planetary gear 6 drives the second upper frame 4 and the second lower frame 5 to rotate through the needle bearing 20. Since the second upper frame 4 and the second lower frame 5 are fixedly connected to the first upper frame 2 and the first lower frame 3 respectively by bolts, the first upper frame 2 rotates as the output end with a reduction gear.

[0087] Example 4

[0088] like Figure 7-8 As shown, a NGW type planetary reducer that can be installed by a backlash elimination method includes a fixed ring gear 1, a sun gear 8, a planet carrier assembly, and a first planet gear 6. The fixed ring gear 1 is provided with a planet carrier assembly, the planet carrier assembly is connected to the output shaft, and is rotatably arranged in the fixed ring gear; three first planet gears 6 are arranged on the planet carrier assembly through planet shafts 9; the sun gear 8 is connected to the input shaft, and the sun gear 8 is meshed with the first planet gear 6. The outer wall of the sun gear 8 is provided with a spline for inputting torque.

[0089] The NGW type planetary reducer is basically similar to that of Example 2, and the same contents will not be repeated here.

[0090] Example 5

[0091] like Figure 9-10 As shown, a NGW type planetary reducer that can be installed by the anti-backlash method, the NGW type planetary reducer is basically similar to Example 4, the same content will not be repeated, and only the differences are described below.

[0092] The NGW type planetary reducer is based on the planetary reducer described in Example 4, and adds a second fixed gear ring 23, a second planet carrier 24 and a second sun gear 25. The second fixed gear ring 23 and the first lower frame 3 are fixedly connected by bolts, and the second planet carrier 24 is tightly connected to the sun gear 8 by spline. The outer wall of the sun gear 8 is provided with a spline for inputting torque.

[0093] The second fixed ring gear 23, the second planet carrier 24, the front-stage planetary gear 26 and the second sun gear 25 form a planetary reducer, which serves as the front-stage sun gear 8 of the NGW type planetary reducer.

[0094] Because the expansion stroke of the second frame is very small, the required radius expansion usually does not exceed half of the tooth height of the planetary gear, so the expansion tool does not need a large adjustment stroke. When the accuracy level of each part of the planetary transmission device is high, it is only necessary to machine the notch 15 that can meet the small elastic deformation on the second upper frame 4 and the second lower frame 5 of the second frame.

[0095] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. The non-essential improvements, adjustments or replacements made by those skilled in the art based on the contents of this specification are all within the scope of protection required by the present invention.

Claims

1. A planet carrier assembly, characterized in that: It includes a first frame and a second frame located inside the first frame, the planetary gear is fixed to the second frame through bearings, the two end faces of the second frame and the two end faces of the first frame close to it are respectively installed and fixed by fasteners, at least part of the frame body of the second frame is an elastic structure and / or a split structure, and can change the position of the planetary shaft under the action of external force before being fastened to the first frame.

2. A planetary reducer assembly of a planetary wheel and a ring gear that can be installed by a backlash elimination method, characterized in that: It comprises a fixed gear ring (1), a roller, a first planetary gear (6) and a planetary frame assembly according to claim 1; the frame body of the second frame is provided with alternating notches or the frame body of the second frame is cut at least two places radially to form a split structure, so that it can be deformed, and during the expansion process of the second frame, the first planetary gear (6) and the fixed gear ring (1) are more closely engaged; the first frame is rotatably arranged in the fixed gear ring, and forms a slewing bearing with the fixed gear ring (1) through the roller.

3. A planetary reducer, characterized in that: The planetary reducer comprises a planetary reducer assembly according to claim 2, a sun gear (8) and a second planetary gear (7); the sun gear (8) is used for input, and the planetary frame assembly is used for output; when working, the sun gear (8) drives the second planetary gear (7), and the second planetary gear (7) drives the first planetary gear (6) to roll and mesh with the fixed gear ring (1), and the first planetary gear (6) drives the second frame to rotate through the roller, and the two end faces of the second frame are respectively bolted to the two end faces of the first frame close to it, and the first upper frame body (2) of the first frame serves as the output end to reduce the rotation.

4. The planetary reducer according to claim 3, characterized in that: It also includes a sun gear drive gear (11) and an offset input gear (12). The sun gear drive gear (11) is coaxially fixed with the sun gear (8), and the sun gear drive gear (11) is meshed with the offset input gear (12).

5. A planetary reducer, characterized in that: The planetary reducer comprises a planetary reducer assembly according to claim 2 and a sun gear (8). When the planetary reducer is working, the sun gear (8) is used for input and the planetary frame assembly is used for output. The sun gear (8) drives the first planetary gear (6), the first planetary gear (6) is in rolling engagement with the fixed gear ring (1), and the first planetary gear (6) drives the second frame to rotate through a roller. The two end faces of the second frame are respectively bolted to the two end faces of the first frame close to it, and the first upper frame (2) of the first frame serves as the output end to reduce the rotation.

6. The planetary reducer according to claim 5, characterized in that: It also includes a front-stage planetary reducer assembly, which includes a second fixed ring gear (23), a second planet carrier (24), a front-stage planetary wheel (26) and a second sun wheel (25), wherein the second fixed ring gear (23) and the first lower frame (3) are fixedly connected by bolts, the second planet carrier (24) is tightly connected to the sun wheel (8) by spline fitting, and the second sun wheel (25) drives the sun wheel (8) to rotate by driving the second planet carrier (24).

7. The planetary reducer according to claim 3 or 5, characterized in that: The first frame is a rigid frame, comprising a first upper frame body (2) and a first lower frame body (3), the first upper frame body (2) and the first lower frame body (3) being fastened by bolts, and the space inside the first upper frame body (2) and the first lower frame body (3) is used to accommodate the first planetary gear (6) and the second frame; The second frame is a flexible frame, comprising a second upper frame body (4) and a second lower frame body (5), wherein the second upper frame body (4) and the second lower frame body (5) are provided with notches in the form of grooves, or the second upper frame body (4) and the second lower frame body (5) are cut at least two places along the frame radial direction to form a split structure, which is used to make the second upper frame body (4) and the second lower frame body (5) elastically deformed, and can elastically lengthen the pitch diameter of the axis of the planetary gear on the second upper frame body (4) and the second lower frame body (5); Furthermore, an axial hole is provided at a corresponding position in the middle of the first frame and the second frame for inserting a sun gear or an expansion tool.

8. The planetary reducer according to claim 7, characterized in that: The first upper frame (2) and the first lower frame (3) are provided with first holes corresponding to their positions, and the first upper frame and the first lower frame (3) are fixedly connected by a first bolt (17); the first upper frame (2) and the second upper frame (4) / the first lower frame (3) and the second lower frame (5) are provided with second holes corresponding to their positions, and the first upper frame (2) and the second upper frame (4) / the first lower frame (3) and the second lower frame (5) are fixedly connected by a second bolt (18), respectively, and the second hole on the first frame is slightly larger than the diameter of the bolt, so that the second frame can be adapted to the second hole on it after it is opened.

9. The planetary reducer according to claim 7, characterized in that: The first lower frame (3) comprises an annular body and a support column (16), a plurality of clearance holes (19) are provided on the annular body, and the support column (16) and the clearance holes (16) are arranged at intervals; the second upper frame (4) and the second lower frame (5) comprise an annular structure and three bosses extending radially along the outer wall of the annular structure, a through hole is provided on each boss as a planetary shaft hole, and the first planetary gear (6) is fixed to the second frame through a bearing.

10. The backlash-eliminating installation method for a planetary reducer according to claim 3 or 5, characterized in that: Before the sun gear is installed on the planetary reducer assembly, the first frame is first fastened with a first bolt (17), and the second frame is connected with a second bolt (18), and the second bolt is in a loose and untightened state, and the second frame is installed in the first frame with a gap; Using an expansion tool to expand the pitch diameter of the planetary gear axis on the second frame, thereby reducing the meshing clearance between the fixed gear ring (1) and the first planetary gear (6); When the fixed gear ring (1) and the first planetary gear (6) are tightly meshed, the second bolt (18) is tightened to make the adjacent end faces of the first frame and the second frame contact, and then the expansion tool is removed and the remaining components are installed.

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