Novel hollow composite planetary reducer and reducer assembly

Abstract

The invention discloses a novel hollow type compound planetary reducer and a reducer assembly, the novel hollow type compound planetary reducer comprises a sun gear serving as an input end, and the sun gear is hollow; an outer ring gear; the multi-layer duplex planet gear set, the sun gear and the outer gear ring form a transmission chain; wherein all the layers of duplex planet gear sets are sequentially connected and transmitted from the lower layer to the upper layer, the lowest layer of duplex planet gear set is connected with the sun gear, and the highest layer of duplex planet gear set is connected with the outer gear ring; and the split type planet carrier is an output end, and the split type planet carrier is used for fixedly installing the multi-layer duplex planet wheel set. Multi-time speed change and torque increase are achieved through the multi-layer duplex planet gear set, the assembly difficulty is small, the utilization space is small, and through combination of the single gear ring and the split planet carrier, transmission chains are shortened, and accumulated errors between the transmission chains are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of reducers, and in particular relates to a novel hollow composite planetary reducer and a reducer assembly. Background Art

[0002] The hollow composite planetary reducer is a widely used industrial product, suitable for various mechanical equipment, including aerospace, wind power, robots, etc. It is mainly used in industries such as industrial robots, medical robots, humanoid robots and quadruped robot dog joints. The design concept of the hollow composite planetary reducer is a hollow reducer structure. In order to facilitate the cable to pass through the middle of the reducer, the maximum speed ratio, output torque and transmission accuracy are obtained with the least number of parts and the shortest transmission chain. The process manufacturing is economical and convenient, and the structural design is scientific and reasonable. However, there are some problems with the hollow planetary reducer at present: the hollow planetary reducer has a small internal space due to its internal hollow structure, resulting in a low speed ratio, a small torque increase, and a long transmission chain that is easy to accumulate errors. Therefore, how to achieve large speed changes and torque increases in a limited space to reduce transmission errors has become an urgent problem to be solved. Summary of the invention

[0003] The purpose of the present invention is to provide a new type of hollow composite planetary reducer and reducer assembly, which utilizes the hollow structure to facilitate the cable to pass through the middle of the reducer, aiming to solve the problems of small speed change and torque increase range, large transmission error, and inconvenience of cable passing through the middle of the reducer while controlling the overall volume of the reducer.

[0004] In order to solve the above problems, the present invention provides a new type of hollow compound planetary reducer, including: a sun gear, which is an input end, and the sun gear is hollow; an outer ring gear; a multi-layer double-linked planetary gear set, which forms a transmission chain with the sun gear and the outer ring gear; wherein each layer of the double-linked planetary gear set is connected and transmitted in sequence from the low layer to the high layer, and the lowest layer of the double-linked planetary gear set is connected to the sun gear, and the highest layer of the double-linked planetary gear set is connected to the outer ring gear; a split planetary carrier, which is the output end, and the split planetary carrier is used to fix the multi-layer double-linked planetary gear set.

[0005] Furthermore, the multi-layer double-linked planetary gear set includes: a single-layer double-linked planetary gear set, including multiple single-layer double-linked planetary gears; a two-layer double-linked planetary gear set, including multiple two-layer double-linked planetary gears; a three-layer double-linked planetary gear set, including multiple three-layer double-linked planetary gears; wherein the single-layer double-linked planetary gear connects the sun gear and the two-layer double-linked planetary gear; the two-layer double-linked planetary gear connects the single-layer double-linked planetary gear and the three-layer double-linked planetary gear; the three-layer double-linked planetary gear connects the two-layer double-linked planetary gear and the outer ring gear.

[0006] Furthermore, the one-layer double-linked planetary gear includes a coaxially arranged one-layer large planetary gear and a coaxially arranged one-layer small planetary gear; a plurality of the one-layer large planetary gears are simultaneously meshed with the sun gear externally and are evenly distributed along the circumference of the sun gear; the two-layer double-linked planetary gear includes a coaxially arranged two-layer large planetary gear and a coaxially arranged two-layer small planetary gear, and the two-layer large planetary gear is correspondingly meshed with the one-layer small planetary gear externally; the three-layer double-linked planetary gear includes a coaxially arranged three-layer large planetary gear and a coaxially arranged three-layer small planetary gear, and the three-layer large planetary gear is correspondingly meshed with the two-layer small planetary gear externally; the three-layer small planetary gear is internally meshed with the outer gear ring.

[0007] Further, the number of the one-layer double-coupled planetary gears is equal to the number of the three-layer double-coupled planetary gears; the number of the two-layer double-coupled planetary gears is twice the number of the one-layer double-coupled planetary gears or is equal to the number of the one-layer double-coupled planetary gears, and when the number of the two-layer double-coupled planetary gears is twice the number of the one-layer double-coupled planetary gears, each of the one-layer double-coupled planetary gears corresponds to two of the two-layer double-coupled planetary gears.

[0008] Furthermore, the number of the first layer of double-coupled planetary gears is 2 to 5, and the second layer of double-coupled planetary gears are connected to the first layer of double-coupled planetary gears on one side or in a symmetrical distribution.

[0009] Furthermore, on the axial projection plane of the sun gear, a line connecting the center of each of the single-layer double-linked planetary gears and the center of its corresponding three-layer double-linked planetary gears passes through the center of the sun gear; a line connecting the center of each of the single-layer double-linked planetary gears and the center of its corresponding three-layer double-linked planetary gears is perpendicular to a line connecting the centers of the corresponding two double-layer double-linked planetary gears.

[0010] Furthermore, the tooth widths of the first layer of small planetary wheels, the second layer of large planetary wheels, the second layer of small planetary wheels and the third layer of large planetary wheels are greater than the tooth widths of the first layer of large planetary wheels and the third layer of small planetary wheels.

[0011] Furthermore, the split planetary carrier includes a front bracket and a rear bracket; the front bracket and the rear bracket are relatively arranged on the front and rear sides of the outer gear ring.

[0012] Furthermore, the front bracket and the rear bracket are connected as a whole via fasteners.

[0013] The present invention also provides a reducer assembly, comprising: a new hollow compound planetary reducer and a motor as described in any one of the above embodiments; the chassis of the new hollow compound planetary reducer is fixedly connected to the outer casing of the motor; the sun gear of the new hollow compound planetary reducer is connected to the output shaft of the motor by crimping, bonding or spline connection.

[0014] Implementing the embodiments of the present invention will have the following beneficial effects:

[0015] The present invention realizes multiple speed changes and torque increases by utilizing a multi-layer double-linked planetary gear set, has low assembly difficulty, and utilizes a small space. Furthermore, by combining a single ring gear with a split planetary carrier, the transmission chain is shortened and the accumulated error between the transmission chains is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic cross-sectional view of a reducer assembly according to an embodiment of the present disclosure;

[0018] Figure 2 A schematic diagram of the external structure of a reducer assembly provided in one embodiment of the present disclosure from one perspective;

[0019] Figure 3 For along Figure 2 Schematic diagram of the cross-sectional structure along the AA line;

[0020] Figure 4 A schematic diagram of the external structure of a reducer assembly provided by an embodiment of the present disclosure from another perspective;

[0021] Figure 5 For along Figure 4 Schematic diagram of the cross-sectional structure along the middle BB line;

[0022] Figure 6 A schematic diagram of the external structure of a reducer assembly provided by an embodiment of the present disclosure from another perspective;

[0023] Figure 7 A schematic diagram of the external structure of a reducer assembly provided by an embodiment of the present disclosure from another perspective;

[0024] Figure 8 A schematic diagram of the transmission principle of a novel hollow composite planetary reducer provided in one embodiment of the present disclosure;

[0025] Fig. 9 A schematic structural diagram of a split planet carrier from one perspective provided in an embodiment of the present disclosure;

[0026] Fig.10 A schematic structural diagram of a split planet carrier from another perspective provided by an embodiment of the present disclosure;

[0027] Fig.11 for Fig.10 Schematic diagram of the middle C direction;

[0028] Fig.12 For along Fig.11 Schematic diagram of the cross-sectional structure of the middle DD line;

[0029] Fig.13 For along Fig.11 Schematic diagram of the cross-sectional structure of the FF line.

[0030] Reference numerals:

[0031] 10. New hollow composite planetary reducer; 11. Sun gear; 12. Outer gear ring; 13. Multi-layer double-linked planetary gear set; 131. One-layer double-linked planetary gear; 1311. One-layer large planetary gear; 1312. One-layer small planetary gear; 132. Two-layer double-linked planetary gear; 1321. Two-layer large planetary gear; 1322. Two-layer small planetary gear; 133. Three-layer double-linked planetary gear; 1331. Three-layer large planetary gear; 1332. Three-layer small planetary gear; Planetary gear; 134, planetary shaft; 14, split planetary carrier; 141, front bracket; 142, rear bracket; 143, locating pin; 144, screw; 145, limit block; 146, fastener mounting table; 147, bearing position; 15, chassis; 16, first bearing; 17, second bearing; 18, third bearing; 19, fourth bearing; 20, motor; 21, housing; 22, motor shaft; 30, reducer assembly. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0033] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0035] The existing planetary reducers have a small internal space due to their hollow internal structure, resulting in a low speed ratio, a small torque increase, and a long transmission chain that is prone to accumulated errors. Therefore, how to achieve large speed changes and torque increases in a limited space to reduce transmission errors has become an urgent problem to be solved. The disclosed embodiment provides a new type of hollow composite planetary reducer and reducer assembly, which achieves multiple speed changes and torque increases by utilizing a multi-layer double-coupled planetary gear set, has low assembly difficulty, and requires little space. In addition, by combining a single ring gear and a split planetary carrier, the transmission chain is shortened and the accumulated errors between the transmission chains are reduced.

[0036] Combination Figures 1 to 13 As shown, the embodiment of the present disclosure provides a new type of hollow compound planetary reducer 10, including a sun gear 11, an outer gear ring 12, a multi-layer double-linked planetary gear set 13 and a split planetary carrier 14. The sun gear 11 is the input end, and the sun gear 11 is hollow. The multi-layer double-linked planetary gear set 13 is arranged between the sun gear 11 and the outer gear ring 12 and fixed by the split planetary carrier 14, and the multi-layer double-linked planetary gear set 13 forms a transmission chain with the sun gear 11 and the outer gear ring 12. The double-linked planetary gear sets of each layer are connected and transmitted in sequence from the low layer to the high layer, and the lowest layer of the double-linked planetary gear set is connected to the sun gear 11, and the highest layer of the double-linked planetary gear set is connected to the outer gear ring 12. The sun gear 11, the outer gear ring 12, the multi-layer double planetary gear set 13 and the split planetary carrier 14 are all installed in the chassis 15. The chassis 15 defines an installation space. The split planetary carrier 14 is installed in the chassis 15 through the first bearing 16. A plurality of bearing positions 147 are arranged in the split planetary carrier 14. The planetary shaft 134 of each group in the multi-layer double planetary gear set 13 is installed in the split planetary carrier 14 through the third bearing 18, so that the rotation of the sun gear 11 drives the self-rotation of each layer of double planetary gears and drives the split planetary carrier 14 to rotate and output. The inside of the chassis 15 is cylindrical, and installation ports are arranged at the front and back. The front end of the housing 21 of the motor 20 is docked and installed with the installation port on the rear side of the chassis 15, and the end of the rear bracket 142 is embedded in the motor 20 from the front end of the housing 21 of the motor 20 and installed on the sun gear 11 shaft through the fourth bearing 19. Both the front bracket and the rear bracket are installed inside the chassis 15 through the first bearing 16, the circumferential outer wall of the front bracket contacts the inner ring of the first bearing 16, and the corresponding outer ring of the first bearing 16 is connected to the inner wall of the chassis 15. The rear bracket is installed in the same way as the front bracket, that is, the circumferential outer wall of the rear bracket is connected to the inner ring of the first bearing 16, and the corresponding outer ring of the first bearing 16 is connected to the inner wall of the chassis 15. In the axial direction, the outer gear ring 12 is fixed between the first bearing 16 of the front bracket installed corresponding to the chassis 15 and the first bearing 16 of the rear bracket installed.

[0037] Combination Figures 1 to 8As shown, the multi-layer double-linked planetary gear set 13 includes a first-layer double-linked planetary gear set 131, a second-layer double-linked planetary gear set 132, and a third-layer double-linked planetary gear set 133. The first-layer double-linked planetary gear set 131 includes a plurality of first-layer double-linked planetary gears 131. The second-layer double-linked planetary gear set 132 includes a plurality of second-layer double-linked planetary gears 132. The third-layer double-linked planetary gear set 133 includes a plurality of third-layer double-linked planetary gears 133. Among them, the first-layer double-linked planetary gear 131 connects the sun gear 11 and the second-layer double-linked planetary gear 132. The second-layer double-linked planetary gear 132 connects the first-layer double-linked planetary gear 131 and the third-layer double-linked planetary gear 133. The third-layer double-linked planetary gear 133 connects the second-layer double-linked planetary gear 132 and the outer gear ring 12.

[0038] In some embodiments, the multi-layer double-coupled planetary gear set 13 may also include a four-layer double-coupled planetary gear set, a five-layer double-coupled planetary gear set, etc., and the number of layers may be increased or decreased as needed.

[0039] Combination Figures 1 to 8 As shown, a layer of double-linked planetary gears 131 includes a layer of large planetary gears 1311 and a layer of small planetary gears 1312 arranged coaxially. A layer of large planetary gears 1311 and a layer of small planetary gears 1312 are arranged in parallel along the axial direction, a layer of large planetary gears 1311 is arranged behind a layer of small planetary gears 1312, and multiple layers of large planetary gears 1311 are simultaneously meshed with the outside of the sun gear 11 and are evenly distributed along the circumference of the sun gear 11. The axis centers of the planetary shafts 134 of multiple layers of double-linked planetary gears 131 are distributed on the same pitch circle. The two-layer double-linked planetary gears 132 include two layers of large planetary gears 1321 and two layers of small planetary gears 1322 arranged coaxially, the two layers of large planetary gears 1321 and the two layers of small planetary gears 1322 are arranged in parallel along the axial direction, the two layers of large planetary gears 1321 are arranged behind the two layers of small planetary gears 1322, and multiple layers of large planetary gears 1321 are distributed along the circumference of the sun gear 11. The axis centers of the planetary shafts 134 of the multiple two-layer double-linked planetary gears 132 are distributed on the same pitch circle. The two-layer large planetary gear 1321 is externally meshed with the one-layer small planetary gear 1312. The three-layer double-linked planetary gear 133 includes three-layer large planetary gears 1331 and three-layer small planetary gears 1332 coaxially arranged, the three-layer large planetary gears 1331 and the three-layer small planetary gears 1332 are arranged in parallel along the axial direction, the three-layer large planetary gears 1331 are arranged behind the three-layer small planetary gears 1332, and the multiple three-layer large planetary gears 1331 are uniformly distributed along the circumference of the sun gear 11. The axis centers of the planetary shafts 134 of the multiple three-layer double-linked planetary gears 133 are distributed on the same pitch circle. The three-layer large planetary gear 1331 is externally meshed with the two-layer small planetary gear 1322. The three-layer small planetary gear 1332 is internally meshed with the outer gear ring 12.

[0040] Combination Figures 3 to 8As shown, the number of the first-layer double-linked planetary gears 131 is equal to the number of the third-layer double-linked planetary gears 133. The number of the second-layer double-linked planetary gears 132 is twice the number of the first-layer double-linked planetary gears 131 or is equal to the number of the first-layer double-linked planetary gears 131, and when the number of the second-layer double-linked planetary gears 132 is twice the number of the first-layer double-linked planetary gears 131, each first-layer double-linked planetary gear 131 corresponds to two second-layer double-linked planetary gears 132. The plurality of first-layer double-linked planetary gears 131 are evenly distributed along the circumference of the sun gear 11, and the plurality of third-layer double-linked planetary gears 133 correspond one-to-one to the plurality of first-layer double-linked planetary gears 131 and are axially located on the outside of the first-layer double-linked planetary gears 131. When the number of the two-layer double-coupled planetary gears 132 is twice the number of the one-layer double-coupled planetary gears 131, each one-layer double-coupled planetary gear 131 is meshed with two two-layer double-coupled planetary gears 132 at the same time, and the two two-layer double-coupled planetary gears 132 are axially distributed on both sides of the corresponding one-layer double-coupled planetary gears 131, so that the one-layer small planetary gear 1312 of each one-layer double-coupled planetary gear 131 is meshed with two two-layer large planetary gears 1321, and each three-layer large planetary gear 1331 is meshed with two two-layer small planetary gears 1322, so that the strength of the two-layer planetary gear set is enhanced.

[0041] Combination Figures 1 to 8 As shown, the number of double-coupled planetary gears 131 in one layer ranges from 2 to 5. There are 2 double-coupled planetary gears 131 in one layer, corresponding to 4 double-coupled planetary gears 132 in two layers, and 2 double-coupled planetary gears 133 in three layers. There are 3 double-coupled planetary gears 131 in one layer, corresponding to 6 double-coupled planetary gears 132 in two layers, and 3 double-coupled planetary gears 133 in three layers. There are 4 double-coupled planetary gears 131 in one layer, corresponding to 8 double-coupled planetary gears 132 in two layers, and 4 double-coupled planetary gears 133 in three layers. There are 5 double-coupled planetary gears 131 in one layer, corresponding to 5 double-coupled planetary gears 132 in two layers, and 5 double-coupled planetary gears 133 in three layers. When the number of the two-layer double-coupled planetary gears 132 is twice the number of the one-layer double-coupled planetary gears 131, each one-layer double-coupled planetary gear 131 corresponds to two two-layer double-coupled planetary gears 132, and the two two-layer double-coupled planetary gears 132 are symmetrically distributed along the circumferential direction on both sides of the corresponding one-layer double-coupled planetary gear 131. When the number of the two-layer double-coupled planetary gears 132 is equal to the number of the one-layer double-coupled planetary gears 131, each one-layer double-coupled planetary gear 131 is unilaterally meshed with one two-layer double-coupled planetary gear 132.

[0042] Combination Figures 3 to 8As shown, on the axial projection plane of the sun gear 11, the line connecting the center of each one-layer double-coupled planetary gear 131 and the center of the corresponding three-layer double-coupled planetary gear 133 passes through the center of the sun gear 11. The line connecting the center of each one-layer double-coupled planetary gear 131 and the center of the corresponding three-layer double-coupled planetary gear 133 is perpendicular to the line connecting the centers of the corresponding two two-layer double-coupled planetary gears 132. So that each one-layer small planetary gear 1312 is correspondingly meshed with two two-layer large planetary gears 1321, and the two large planetary gears are respectively arranged on both sides of the one-layer small planetary gear 1312. Each three-layer large planetary gear 1331 is correspondingly meshed with two two-layer small planetary gears 1322, and the two two-layer small planetary gears 1322 are respectively arranged on both sides of the corresponding three-layer large planetary gear 1331, so that the one-layer small planetary gear 1312 and the three-layer large planetary gear 1331 are evenly stressed during operation.

[0043] Combination Figures 1 to 8 As shown, the tooth widths of the first layer of small planetary wheels 1312, the second layer of large planetary wheels 1321, the second layer of small planetary wheels 1322 and the third layer of large planetary wheels 1331 are greater than the tooth widths of the first layer of large planetary wheels 1311 and the third layer of small planetary wheels 1332. In some embodiments, the number of the second layer of planetary wheels and the first layer of planetary wheels is equal, and the tooth widths of the gears meshing with the second layer of planetary wheels are increased to enhance the strength of the gears.

[0044] Combination Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Fig. 9 , Fig.10 , Fig.11 , Fig.12 and Fig.13 As shown, the split planetary carrier 14 includes a front bracket 141 and a rear bracket 142. The front bracket 141 and the rear bracket 142 are relatively arranged on the front and rear sides of the outer gear ring 12. The front bracket 141 and the rear bracket 142 are arranged opposite to each other in the axial direction, and the multi-layer double-linked planetary gear set 13 is fixedly installed between the front bracket 141 and the rear bracket 142, wherein each layer of the double-linked planetary gear set is installed between the front bracket 141 and the rear bracket 142 through the planetary shaft 134 and the third bearing 18. After the front bracket 141 and the rear bracket 142 are combined, a relative bearing position 147 is set corresponding to each planetary shaft 134, and the two ends of the planetary shaft 134 are respectively installed to the front bracket 141 and the rear bracket 142 through the third bearing 18 to fix each layer of the double-linked planetary gear set.

[0045] Combination Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Fig. 9 , Fig.10 , Fig.11 , Fig.12 and Fig.13 As shown, the front bracket 141 and the rear bracket 142 are connected as a whole by fasteners. The multi-layer double planetary gear set 13 shares a split planetary carrier 14, which reduces the volume and has high structural strength. The front bracket 141 and the rear bracket 142 are provided with a fastener mounting platform 146 protruding toward the axial direction at the gap between adjacent bearing positions 147 along the circumferential direction, and a fastener mounting hole is opened in the fastener mounting platform 146 to connect the front bracket 141 and the rear bracket 142 as a whole by fasteners. The fasteners include one or more of screws 144, bolts and positioning pins 143.

[0046] In some embodiments, a limit block 145 is further included. The limit block 145 is mounted to the front bracket 141 by screws to limit the relative position of the front bracket 141 in the assembly of other components.

[0047] Combination Figures 1 to 13 As shown, the embodiment of the present disclosure also provides a reducer assembly 30, including: a new hollow composite planetary reducer 10 and a motor 20 as in any of the above embodiments. The chassis 15 of the new hollow composite planetary reducer 10 is fixedly connected to the housing 21 of the motor 20. The sun gear 11 of the new hollow composite planetary reducer 10 is connected to the output shaft of the motor 20 by crimping, bonding or spline connection. The chassis 15 of the new hollow composite planetary reducer 10 is connected to the housing 21 of the motor 20 by fasteners. One end of the sun gear 11 is axially connected to the output shaft of the motor 20 so that the motor 20 provides power to drive the sun gear 11 to rotate. The rear end of the rear bracket 142 is axially embedded in the motor 20 and is rotatably connected to the sun gear 11 in the motor 20 through the fourth bearing 19. The front end of the rear bracket 142 is located in the chassis 15, and a bearing position 147 is provided corresponding to the planetary shaft 134 of each layer of the double planetary gear to install the third bearing 18 to install the corresponding planetary shaft 134.

[0048] Exemplarily, the novel hollow composite planetary reducer 10 provided in the embodiment of the present disclosure can be installed according to the following steps:

[0049] Step 1: First, install the first bearing 16 , the second bearing 17 and the third bearing 18 to the corresponding bearing positions 147 of the front bracket 141 .

[0050] Step 2: Install the bearing 3 to the corresponding bearing position 147 of the rear bracket 142 .

[0051] Step 3: Install the front bracket 141 with the first bearing 16 , the second bearing 17 and the third bearing 18 to the corresponding position of the chassis 15 .

[0052] Step 4: Install the outer gear ring 12 into the chassis 15 .

[0053] In this step, the outer wall of the outer gear ring 12 and the inner wall of the chassis 15 are fixedly connected by crimping and bonding.

[0054] Step 5: Install the first-layer double-linked planetary gear 131 , the second-layer double-linked planetary gear 132 and the third-layer double-linked planetary gear 133 to the front bracket 141 .

[0055] In this step, the first layer double planetary gear 131, the second layer double planetary gear 132 and the third layer double planetary gear 133 should be installed in the corresponding bearing position 147 of the front bracket 141, wherein the corresponding positions are combined with Figure 8 shown.

[0056] Step 6: Install the positioning pin 143 to the front bracket 141 .

[0057] Step 7: Install the rear bracket 142 until it is engaged with the front bracket 141 .

[0058] Step 8: Fix the front bracket 141 and the rear bracket 142 together by fasteners.

[0059] Step nine: Install the first bearing 16 corresponding to the rear bracket 142 between the rear bracket 142 and the chassis 15 .

[0060] Step 10: Install the fourth bearing 19 to the rear bracket 142 .

[0061] Step 11: Insert the sun gear 11 axially into place through the fourth bearing 19 .

[0062] Step 12: Install and fix the motor 20 and the novel hollow composite planetary reducer 10.

[0063] In this step, the motor 20 is assembled first, and the assembled motor 20 is docked and fixed with the new hollow compound planetary reducer 10. Note that during the docking and installation process of the motor 20 and the new hollow compound planetary reducer 10, the motor shaft 22 and the sun gear 11 should correspond accurately and be connected by crimping, bonding or spline connection. At the same time, the housing 21 of the motor 20 and the chassis 15 should correspond accurately and be connected by fasteners.

[0064] Exemplarily, the working principle of the novel hollow composite planetary reducer 10 provided in the embodiment of the present disclosure is as follows:

[0065] The hollow compound planetary reducer has four main structural features: 1) single gear bracket (front and rear split) single gear ring; 2) four-fold torque increase: 3) single-stage transmission; 4) four-fold speed change.

[0066] 1. The split planet carrier 14 is connected to an integral body, an outer gear ring 12, at the front and rear. The front and rear split planet carriers 14 are assembled into an integral body by positioning pins 143 and screws 144. All double-linked planetary gear sets share one split planet carrier 14, which reduces costs and increases the strength of the mechanism.

[0067] 2. Single-stage transmission. The new hollow compound planetary reducer 10 is composed of a sun gear 11 input, 4 single-layer double-linked planetary gears 131, 8 two-layer double-linked planetary gears 132, 4 three-layer double-linked planetary gears 133 and an outer ring gear 12. Compared with the traditional hollow planetary reducer, it uses a fixed integrated split planet carrier 14 and a single outer ring gear 12, which shortens the transmission chain and reduces the cumulative error.

[0068] 3. Four times of torque increase, one sun gear 11 input is meshed with a layer of large planetary gears 1311 of four one-layer double-linked planetary gears 131 to achieve the first torque increase; one layer of small planetary gears 1312 of four one-layer double-linked planetary gears 131 is meshed with the second layer of large planetary gears 1321 of their respective two adjacent two-layer double-linked planetary gears 132, with 8 overlapping teeth, to achieve the second torque increase; the second layer of small planetary gears 1322 of each two-layer double-linked planetary gear 132 is meshed with the three-layer large planetary gears 1331 of their respective adjacent three-layer double-linked planetary gears 133, with 8 overlapping teeth, to achieve the third torque increase; finally, the three-layer small planetary gears 1332 of the four three-layer double-linked planetary gears 133 are meshed with the outer ring gear 12. The original structural strength of the planetary gear meshing part was weak, but it was strengthened because the number of overlapping teeth was increased by 1 times. The structural strength of the meshing part of the outer gear ring 12 was stronger, and the number of planetary gear meshing layers was increased, which was beneficial to power diversion and avoidance of stress concentration during torque transmission, and the total torque was increased by more than 1 times.

[0069] 4. Four-speed shift: the first layer of large planetary gear 1311 of the first layer of double-linked planetary gear 131 meshes with the input gear of the sun gear 11 for the first speed shift. The second layer of large planetary gear 1321 of the second layer of double-linked planetary gear 132 meshes with the first layer of small planetary gear 1312 of the first layer of double-linked planetary gear 131 for the second speed shift. The third layer of large planetary gear 1331 of the third layer of double-linked planetary gear 133 meshes with the second layer of small planetary gear 1322 of the second layer of double-linked planetary gear 132 for the third speed shift. Finally, the outer gear ring 12 meshes with the third layer of small planetary gear 1332 of the third layer of double-linked planetary gear 133.

[0070] The overall speed ratio can be calculated using the following formula:

[0071] i=Z 行大1 / Z 太阳 ×Z 行大2 / Z 行小1 ×Z 行大3 / Z 行小2 ×Z 圈 / Z 行小3 +1. Where i is the total speed ratio; Z行大1 The number of teeth of the large planetary gear is 1311; Z 太阳 The number of teeth of the sun gear is 11; Z 行小1 The number of teeth of the asteroid wheel is 1312; Z 行大3 The number of teeth of the three-layer large planetary gear is 1331; Z 行小2 The number of teeth of the second-layer asteroid wheel is 1322; Z 圈 The number of teeth on the outer ring gear is 12; Z 行小3 The number of teeth on the three-layer asteroid wheel is 1332.

[0072] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations, and unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of one or more associated listings. In addition, when used in this application, the term "comprise" and its variants "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but not

[0073] The existence or addition of one or more other features, integral bodies, steps, operations, elements, components and / or groups thereof is excluded. In the absence of further restrictions, the elements defined by the statement "comprising a ..." do not exclude the existence of other identical elements in the process, method or device comprising the elements. Herein, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the embodiments may refer to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, the relevant parts may refer to the description of the method part.

[0074] The above-described embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. The technical features of the above-described embodiments can be arbitrarily combined. In order to make the description concise, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A new type of hollow composite planetary reducer, characterized in that: include: The sun gear is the input end and is hollow; External gear ring; A multi-layer double planetary gear set, forming a transmission chain with the sun gear and the outer gear ring; The double planetary gear sets of each layer are connected and driven in sequence from the lowest layer to the highest layer, and the double planetary gear set of the lowest layer is connected to the sun gear, and the double planetary gear set of the highest layer is connected to the outer gear ring; The split planet carrier is the output end, and the split planet carrier is used to fix the multi-layer double planetary gear set.

2. The novel hollow composite planetary reducer according to claim 1 is characterized in that: The multi-layer double planetary gear set comprises: A double-linked planetary gear set, comprising a plurality of double-linked planetary gears; A two-layer double-linked planetary gear set, comprising a plurality of two-layer double-linked planetary gears; A three-layer double-linked planetary gear set, comprising a plurality of three-layer double-linked planetary gears; Among them, the one-layer double-linked planetary gear connects the sun gear and the two-layer double-linked planetary gear; the two-layer double-linked planetary gear connects the one-layer double-linked planetary gear and the three-layer double-linked planetary gear; the three-layer double-linked planetary gear connects the two-layer double-linked planetary gear and the outer gear ring.

3. The novel hollow composite planetary reducer according to claim 2 is characterized in that: The one-layer double planetary gear comprises a layer of large planetary gear and a layer of small planetary gear arranged coaxially; a plurality of the one-layer large planetary gears are simultaneously meshed with the outer surface of the sun gear and are evenly distributed along the circumference of the sun gear; The two-layer double planetary gear comprises two layers of large planetary gears and two layers of small planetary gears which are coaxially arranged, and the two layers of large planetary gears are externally meshed with the one layer of small planetary gears; The three-layer double planetary gear comprises three layers of large planetary gears and three layers of small planetary gears arranged coaxially, the three layers of large planetary gears are externally meshed with the two layers of small planetary gears respectively; the three layers of small planetary gears are internally meshed with the outer gear ring.

4. The novel hollow composite planetary reducer according to claim 2 or 3, characterized in that: The number of the one-layer double-coupled planetary gears is equal to the number of the three-layer double-coupled planetary gears; the number of the two-layer double-coupled planetary gears is twice the number of the one-layer double-coupled planetary gears or is equal to the number of the one-layer double-coupled planetary gears, and when the number of the two-layer double-coupled planetary gears is twice the number of the one-layer double-coupled planetary gears, each of the one-layer double-coupled planetary gears corresponds to two of the two-layer double-coupled planetary gears.

5. The novel hollow composite planetary reducer according to claim 4 is characterized in that: The number of the first layer of double-coupled planetary gears ranges from 2 to 5, and the second layer of double-coupled planetary gears are connected to the first layer of double-coupled planetary gears on one side or in a symmetrical distribution.

6. The novel hollow composite planetary reducer according to claim 4 is characterized in that: On the axial projection plane of the sun gear, a line connecting the center of each of the one-layer double-linked planetary gears and the center of its corresponding three-layer double-linked planetary gears passes through the center of the sun gear; a line connecting the center of each of the one-layer double-linked planetary gears and the center of its corresponding three-layer double-linked planetary gears is perpendicular to a line connecting the centers of the corresponding two two-layer double-linked planetary gears.

7. The novel hollow composite planetary reducer according to claim 2 or 3, characterized in that: The tooth widths of the first layer of small planetary wheels, the second layer of large planetary wheels, the second layer of small planetary wheels and the third layer of large planetary wheels are greater than the tooth widths of the first layer of large planetary wheels and the third layer of small planetary wheels.

8. The novel hollow composite planetary reducer according to claim 1 is characterized in that: The split planet carrier comprises a front bracket and a rear bracket; the front bracket and the rear bracket are arranged relatively at the front and rear sides of the outer gear ring.

9. The novel hollow composite planetary reducer according to claim 7 is characterized in that: The front bracket and the rear bracket are connected as a whole through fasteners.

10. A reducer assembly, characterized in that: include: The novel hollow composite planetary reducer and motor as claimed in any one of claims 1 to 9; The chassis of the novel hollow composite planetary reducer is fixedly connected to the housing of the motor; The sun gear of the novel hollow composite planetary reducer is connected to the output shaft of the motor by crimping, bonding or spline connection.

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