Self-balancing dual parallel compound nutator reducer

Abstract

This electromechanical parallel compound nutator reducer utilizes the concept of mechatronics, symmetrically arranging two parallel compound nutator transmission components with identical structural parameters along their axes. Two motor stator windings with identical structural and electrical parameters are connected in series or parallel, forming a self-balancing double parallel compound nutator reducer that rotates synchronously in the same direction. At any axial section passing through the line connecting the centers of the two compound nutators, the compound nutators oscillate symmetrically in opposite directions around their respective centers. Besides the circumferential forces generating the same-direction rotational torque, the forces acting on the symmetrical components within the reducer are self-balancing, resulting in no external vibration impact. Because four sets of gear teeth mesh simultaneously for reduction, and the central partition and two conical fixed gear rings, the low-speed moving ring of the compound nutator and the double-direction thrust ball bearing, and the drum-shaped spline teeth for output torque are integrated into one unit, the reducer features a compact structure, high load-bearing capacity, good rigidity, high transmission accuracy, and high transmission efficiency.

Description

Technical Field

[0001] This invention belongs to the field of mechanical transmission technology, and specifically relates to a self-balancing double parallel compound nutator reducer. Background Technology

[0002] With the popularization of intelligent manufacturing technology and the increasing number of application scenarios, the application conditions for electro-hydraulic control devices in embodied intelligent machinery, industrial robotic arms, and aerospace are becoming increasingly demanding. This has led to a continuous increase in the demand for high-power-density mechatronic reduction gears with large reduction ratios, compact structures, high transmission accuracy, and good rigidity. Although harmonic reducers have advantages such as large transmission ratios, simple structures, coaxial transmission, small size, and high transmission accuracy, their core principle—which utilizes the elastic deformation of flexible parts during operation to generate harmonic motion to transmit motion and power—also has disadvantages such as short lifespan, low rigidity, low load capacity, and low transmission efficiency. Currently, they are mainly used in light-load parts such as the forearms and wrists of embodied intelligent machinery and robots.

[0003] RV reducers also possess advantages such as large reduction ratios, coaxial transmission, high rigidity, high load-bearing capacity, and higher transmission efficiency than harmonic reducers. However, their complex structure, numerous components, large size and weight, and high cost make miniaturization difficult. Currently, they are mainly used in heavy-duty parts such as the upper arm and waist of industrial robots. Planetary gear reducers, while offering high transmission efficiency, coaxial transmission, and high rigidity, suffer from small single-stage reduction ratios and low transmission accuracy due to backlash.

[0004] The working principle of a nutated reducer is essentially the same as that of a harmonic reducer. It utilizes the axial oscillation of the nutating wheel to achieve a small tooth difference meshing between the moving gear ring on the nutating wheel and the fixed gear ring on the fixed wheel, which has slightly fewer teeth, thus achieving a large reduction ratio. Because of the large number of meshing teeth and the absence or few flexible working parts, it has advantages such as high rigidity, simple structure, coaxial transmission, high load-bearing capacity, and high transmission accuracy. However, due to the axial oscillation of the nutating wheel, it also suffers from periodic rotational and torsional vibrations and low transmission efficiency, making it unsuitable for high-speed input motion conditions. Currently, its applications are limited and mostly single-component, with series and parallel face-to-face reducer solutions proposed and applied in limited quantities.

[0005] The invention patent application "Mechatronic Parallel Composite Nuttow Gear Reducer" (Publication No.: CN 118959555 A) proposes six types of mechatronic parallel composite nuttow gear reducers. These reducers combine the oscillating input nuttow gears of two nuttow transmission components into one unit. A set of extended oscillating rod bearings on the outer (or inner) circular side of the composite nuttow gear's cross-section performs axial centering oscillation in the inclined ring raceway groove on the high-speed rotor of the motor. The planar moving gear rings on both ends of the composite nuttow gear mesh with the conical fixed gear rings on the end caps of the motor stator at a 180° difference, forming a nuttow transmission. This allows half of the motor input torque to be proportionally amplified by the two sets of back-to-back parallel nuttow components. The rotational output is achieved through a variable stiffness angle torque transmission connector on the inner hole (or outer circular surface) of the composite nuttow gear, characterized by high circumferential stiffness and low axial stiffness. The load-bearing capacity, rigidity, and efficiency of the nutation reducer have been improved, making its structure more compact. However, the problem of periodic rotational torsional vibration affecting the external environment of this parallel composite nutation reducer has not yet been solved. Summary of the Invention

[0006] In view of the deficiencies of existing inventions, this invention proposes four types of self-balancing double parallel compound nutator reducers. Based on the parallel compound nutator reducer transmission concept proposed in invention patent application CN 118959555 A, two parallel compound nutator transmission components with the same structural parameters are arranged axially symmetrically. The stator windings of two motors with the same structure and electrical parameters are connected in series or in parallel to form a combined motor. This causes the two inner or outer rotating drums, which are separated by a partition plate and have the same structure and electrical parameters and are coaxial, to rotate in the same direction and at high speed synchronously (or the gear pairs at both ends of a double-headed motor are used to make the two rotating drums rotate in the same direction and at high speed synchronously in a parallel shaft gear transmission manner). This drives the two compound nutator wheels to oscillate in opposite directions around their respective centers at the same angular velocity on any axial section passing through the line connecting their centers. Therefore, in addition to the circumferential forces that generate the same direction of rotational torque, this invention utilizes the principle that the forces acting on each symmetrical component in the reducer cancel each other out and are self-balanced, thus successfully eliminating the persistent problem of the nutation reducer having a periodic rotational torsional vibration effect on the external environment.

[0007] The reducer is composed of a high-speed moving part, a low-speed moving part, and a stationary part, compactly arranged radially and axially. The high-speed moving part consists of a rotating drum or a rotating drum with radial gear integrated with the rotor of the combined motor (both types of rotating drums have a slanted annular groove with the same nutation angle β assembled from multiple parts on the inner or outer wall), two high-speed moving rings of a double-direction thrust ball bearing, and a ball-cage assembly. Two sets are arranged axially symmetrically. They are supported on the stationary part by four sets of sealed angular contact ball bearings, which also separate the motor compartment from the reducer compartment. The low-speed moving part consists of two compound nutation wheels integrated with the low-speed moving rings of the double-direction thrust ball bearing, and a rotatable hollow shaft or housing connected by a drum-shaped tooth spline on its inner hole or outer surface. It is supported on two fixed end covers by a pair of angular contact ball bearings or a pair of tapered roller bearings. The stationary components consist of the stator housing or stator shaft of the assembled motor (or the housing or hollow shaft of the fixed dual-head motor), end caps with integrated conical stator gear rings fixed at both ends, and a central partition plate with two integrated conical stator gear rings fixed in its middle.

[0008] The composite nutation wheel and its transmission components perform three functions: First, as the low-speed moving ring of the double-direction thrust ball bearing, the nutation angle β oblique ring groove assembled on the inner and outer walls of the rotating cylinder transforms the rotational motion of the two high-speed moving rings of the double-direction thrust ball bearing into a low-speed oscillation around its own center; second, through the inner conical moving gear rings with the same module and tooth profile integrated on both end faces, corresponding portions of the gear teeth mesh with the corresponding surfaces of the conical fixed gear rings integrated on an end cover and the conical fixed gear rings integrated on the middle partition, respectively, in directions 180° apart circumferentially. The module of the two conical fixed gear rings... The number of teeth and tooth profile are the same as those of the moving gear ring, but the number of teeth is slightly less than that of the moving gear ring. Since the moving and stationary gear rings mesh with a small tooth difference, two sets of nutation reduction transmission gear teeth mesh on a compound nutation wheel, causing it to rotate at a low speed. This low-speed oscillation is superimposed on the above-mentioned low-speed oscillation, thus forming nutation motion. Furthermore, the torque amplified by the meshing of these two sets of nutation transmission gear teeth is superimposed on the mid-section of the compound nutation wheel and output through the drum-shaped tooth spline connection on its inner hole or outer circular surface, via a rotatable hollow shaft or housing. The axial oscillation torque is transmitted to the stationary component via the support bearing.

[0009] For a parallel compound nutator drive assembly with two axisymmetrically arranged composite nutator wheels, there are four sets of nutator drive gear teeth with the same tooth profile, module, and tooth difference on the four end faces of the two composite nutator wheels. These teeth mesh symmetrically with a small tooth difference, with a 180° difference in both circumferential directions, to proportionally amplify the high-speed, low-torque input from the combined motor or dual-head motor in parallel. The amplified torque in the same direction is superimposed on the mid-section of the composite nutator wheels in pairs, and then output outward through the torque output drum-shaped spline with the same structure on the inner hole or outer circumference of the two composite nutator wheels, and then superimposed again through a rotating hollow shaft or housing. The radial and axial external forces at the output end are borne by a pair of angular contact ball bearings or a pair of tapered roller bearings supporting the hollow shaft or housing between the two fixed end covers. In contrast, the four conical fixed gear rings with a diameter of 180° or less and a 2β angle are arranged in pairs with their conical surfaces facing each other, and are axisymmetrically parallel.

[0010] When the difference in the number of teeth between two parallel compound nutator drive components with identical structural parameters is odd, the two conical fixed gear rings on the partition plate and the conical fixed gear rings on the end caps need to be staggered by half a tooth in the circumferential direction for installation and fixation. When the difference in the number of teeth between the two drive components is even, no staggered tooth installation is required in the circumferential direction. Because there are four sets of gear teeth meshing and reducing speed at the same time, and the partition plate and the two conical fixed gear rings, the two compound nutator wheels and the low-speed moving rings of the double-direction thrust ball bearings and the drum spline teeth, the combined motor rotor and the drum are all integrated into one unit, this reducer with a power source has the characteristics of compact radial and axial structure, large load-bearing capacity, good rigidity, high transmission accuracy and transmission efficiency, and can further improve the power density of the parallel compound nutator reducer. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of a parallel composite nutation reducer that integrates electromechanical components with a single transmission element.

[0012] Figure 2 This is a schematic diagram of a preferred embodiment of the present invention—a self-balancing dual parallel compound nutation wheel reducer with combined motor drive shaft output;

[0013] Figure 3 This is a schematic diagram of the structure of the self-balancing dual parallel compound nutating wheel reducer with dual-head motor drive shaft output of the present invention.

[0014] Figure 4 This is a schematic diagram of the structure of the self-balancing dual parallel composite nutating wheel reducer output by the combined motor drive housing of the present invention.

[0015] Figure 5 This is a schematic diagram of the structure of the self-balancing dual parallel compound nutation wheel reducer with dual-head motor drive housing output of the present invention. Detailed Implementation

[0016] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0017] In the following description, specific details, such as particular internal techniques, are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will appreciate that the invention may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, and installation methods have been omitted so as not to obscure the description of the invention with unnecessary detail.

[0018] Figure 1 A schematic diagram of a parallel composite nutation reducer with a single transmission component, based on a preferred embodiment of invention patent application CN 118959555 A, is provided. The nutation reducer is embedded inside the motor. Two end caps A4, each integrating a conical fixed gear ring A17, are fixed to the motor housing A12 by screws A9. A hollow shaft A1 is supported on the two end caps A4 by a pair of angular contact bearings A3 and is axially pre-tightened by two nuts A2. The two end faces of the composite nutation wheel A5 integrate planar moving gear rings A16 with the same module and tooth profile. The module and tooth profile of the conical fixed gear ring A17 are the same as those of the planar moving gear ring A16, but the number of teeth Z2 of the conical fixed gear ring A17 is less than the number of teeth Z1 of the planar moving gear ring A16. The outer circle of the motor rotor A7 is inlaid with a permanent magnet A10, and its inner circle has a β-angle inclined annular raceway groove due to the assembly of the inclined end face sleeve A15. It is supported on the end caps A4 by a pair of sealed angular contact ball bearings A6, which also separate the motor compartment from the reducer compartment.

[0019] like Figure 1 As shown, power line A8 passes through the side wall hole of left end cover A4 and is electrically connected to motor stator A11. When motor stator A11 is energized and drives rotor A7 to rotate at high speed, the outer rings of three or more guide needle roller bearings A13, evenly arranged on the outer circumference of the compound nutating wheel A5 via pin shaft A14, roll at high speed in the β-angle inclined ring raceway groove of the inner circumference wall of motor rotor A7, causing the compound nutating wheel A5 to perform a centering axial oscillation. Because the planar moving gear rings A16 on both ends of the compound nutating wheel A5 are always engaged with the conical fixed gear rings on both ends of the end cover A4 with a small tooth difference at the two end faces that are 180° apart in the circumferential direction, the compound nutating wheel A5 is forced to rotate at low speed in the circumferential direction at the same time, forming a nutating transmission. That is, the two nutating transmission components on both ends of the compound nutating wheel A5 are as follows: Figure 1As shown in the functional block diagram on the right, it actually performs a proportional amplification of half of the motor input torque in a back-to-back parallel connection. The two parallel amplified torques are superimposed on the mid-section of the compound nutator A5, and then output to the hollow shaft A1 through the inner circle side of the compound nutator A5 and the drum-shaped spline A18 in the middle of the outer circle of the hollow shaft A1, thereby driving the external connecting parts connected to the hollow shaft A1. The radial and axial forces outside the output end are borne by a pair of angular contact ball bearings A3.

[0020] It should be noted that since the compound nutator A5 is subjected to opposing forces on its two end faces that are 180° apart in the circumferential direction, its axial forces can cancel each other out. However, the time-varying rotational oscillation torque caused by the axial force is transmitted to the end cover A4 through the angular contact ball bearing A6. The drum spline A18 only outputs the rotational motion of the compound nutator A5 to the hollow shaft A1, and the radial and axial friction forces on it can also cancel each other out. However, the time-varying rotational oscillation torque caused by the radial and axial friction forces is transmitted to the end cover A4 through the angular contact ball bearing A3. Therefore, this electromechanical parallel compound nutator reducer has a periodic time-varying rotational torsional vibration problem.

[0021] To address the aforementioned problems, this invention will describe a self-balancing dual parallel composite nutating wheel reducer in conjunction with specific embodiments.

[0022] Preferred Embodiment 1

[0023] like Figure 2 As shown, this embodiment provides a self-balancing dual-parallel composite nutator reducer with a combined motor drive shaft output. In this embodiment, the reducer is compactly composed of a high-speed moving component, a low-speed moving component, and a stationary component in the radial and axial directions. The high-speed moving component consists of an inner rotating cylinder 21 (with a β-angle oblique ring groove formed by multiple parts assembled on its inner wall), which is integrated with the inner rotor of the combined motor containing a permanent magnet 5, two high-speed moving rings of a bidirectional thrust ball bearing 19, and a ball-and-cage assembly. Two sets are arranged axially symmetrically. They are supported on two fixed end covers 3 and a central partition 22 by four sets of sealed angular contact ball bearings 7, which also separate the motor compartment from the reducer compartment. The low-speed moving component consists of two composite nutating wheels 15 integrated with the low-speed moving ring 20 of the double-direction thrust ball bearing 19, and a rotatable hollow shaft 10 connected via drum-shaped toothed splines 13 and 12 on its inner bore surface. A pair of angular contact ball bearings 8 support the hollow shaft 10 on two fixed end caps 3 and are pre-tightened by two nuts 11. The stationary component consists of the stator housing 2 of the assembled motor, end caps 3 with integrated conical stationary gear rings 14 fixed to both ends of the stator housing 2 by screws 1, and a central partition 22 with integrated two conical stationary gear rings 9 fixed to the middle of the stator housing 2 by screws 24.

[0024] like Figure 2As shown, the power line 23 passes through the wall hole of the stator housing 2, connecting the windings of two motor stators 4 with the same structure and electrical parameters in parallel to form a combined motor. The two inner rotating cylinders 21 with the same structure and electrical parameters and coaxiality, separated by the partition plate 22, rotate in the same direction and at high speed, driving two composite nutation wheels 15 embedded in the β-angle inclined ring groove on the inner wall of the inner rotating cylinder 21 via the bidirectional thrust ball bearing 19. On any axial section passing through the line connecting their centers, they oscillate in opposite directions around their respective centers with the same angular velocity. On the inner walls of the two inner rotating cylinders 21, an inclined ring groove with the same nutation angle b is formed by the combination of radial bearing seat sleeve 17 and two thrust bearing seat sleeves 18 with one end of a β-angle inclined surface installed in opposite directions and circumferentially 180° apart via a flat key 6.

[0025] like Figure 2 As shown, on the four end faces of the two composite nutator wheels 15, planar moving gear rings 16 with the same module and tooth profile and an inner cone angle of 180° are integrated. Each of them has a small number of teeth that mesh with the corresponding portion of teeth on the conical fixed gear rings 14 on the two end covers 3, which have the same module and tooth profile but slightly fewer teeth, and on the conical fixed gear rings 9 on both sides of the middle partition 22, with a small tooth difference that is 180° apart in both directions and axially symmetrical. Figure 2 As shown in the functional block diagram on the right, the high-speed, low-torque input from the combined motor is proportionally amplified in parallel for comparison. Figure 1 As shown in the functional block diagram on the right, this embodiment includes an additional set of two torque amplifiers. Four 180°-2β cone-angled fixed gear rings 14 and 9 are arranged parallel and symmetrically in pairs. When the difference in the number of teeth between the planar moving gear ring 16 and the cone-shaped fixed gear rings 14 and 9 is odd, the two cone-shaped fixed gear rings 9 on the partition 22 and the cone-shaped fixed gear rings 14 on the end caps 3 need to be staggered by half a tooth in the circumferential direction for installation and fixation. When the difference in the number of teeth is even, no staggered tooth installation is required in the circumferential direction. Because the two compound nutwheels 15 swing symmetrically in opposite directions around their respective centers, the forces acting on all symmetrical components within the reducer, except for the circumferential force that generates the same-direction rotational torque, cancel each other out and automatically balance. Therefore, the reducer is not affected by time-varying rotational torsional vibrations externally.

[0026] Depend on Figure 2It is understood that the compound nutating wheel 15 has functional structures on all four sides. Its outer circular surface is integrated with the low-speed moving ring 20 of the double-direction thrust ball bearing 19 to realize the low-speed oscillation input of the nutating wheel. The two end faces are integrated with planar moving gear rings 16 of the same module and tooth shape, which respectively mesh with the corresponding surfaces of the conical fixed gear ring 14 integrated on one end cover 3 and the conical fixed gear ring 9 integrated on the middle partition 22. The corresponding gear teeth in the circumferential direction with a small tooth difference mesh, realize the simultaneous parallel deceleration of two sets of nutating transmissions, and make the compound nutating wheel 15 rotate at a low speed. The torque amplified by the meshing of the gear teeth of the two sets of nutating transmissions is superimposed on the mid-section of the compound nutating wheel 15 and then output by the rotatable hollow shaft 10 through the drum-shaped spline teeth 13 on its inner hole and the drum-shaped spline teeth 12 on the hollow shaft 10, which are a pair of variable stiffness with high circumferential stiffness and low axial stiffness. The composite nutating wheel 15 has three functions: input from the outer circle, reduction and amplification of torque at both ends, and output of rotational torque through the inner hole and variable stiffness connecting piece.

[0027] Example 2

[0028] A self-balancing dual-parallel compound nutating wheel reducer with output from a dual-head motor drive shaft, such as Figure 3 As shown, the essential difference between this embodiment and Embodiment 1 lies only in the drive motor. For ease of demonstration and description, all other aspects are omitted. Figure 3 Zhongyu Figure 2 Components with the same structure and function in Example 1 have the same numbering, and their identical functions and structures will not be described in detail again.

[0029] like Figure 3 As shown, the high-speed moving component in this embodiment consists of a rotating cylinder 36 with radial gears on its outer circumference (its inner wall has a β-angle oblique ring groove formed by multiple parts), two high-speed moving rings of a double-direction thrust ball bearing 19, and a ball-and-cage assembly. Two sets are arranged axially symmetrically. They are supported on two fixed end covers 31 and a central partition 37 by four sets of sealed angular contact ball bearings 7, which also separate the motor compartment from the reducer compartment. The low-speed moving component consists of two composite nutating wheels 15 integrated with the low-speed moving ring 20 of the double-direction thrust ball bearing 19, and a rotatable hollow shaft 10 connected by drum-shaped tooth splines 13 and 12 on its inner bore surface. A pair of angular contact ball bearings 8 support the hollow shaft 10 on the two fixed end covers 31 and are pre-tightened with two nuts 10. The stationary components consist of a housing 30 that secures the dual-head motor 34 to the housing 34 with screws 33 and 38, end caps 31 with integrated conical fixed gear rings 14 that are fixed to both ends of the housing 30 with screws 1, and a central partition 37 with integrated two conical fixed gear rings 9 that is fixed to the middle of the housing 30 with screws 24.

[0030] like Figure 3As shown, the dual-head motor 34 is connected to an external power source via a power cable 32 passing through a wall hole in the housing 30. Gears 35 on the output shafts at both ends of the dual-head motor 34 mesh with radial gears on the outer surfaces of the two rotating drums 36. Through a single-stage gear transmission in a parallel-axis manner, they drive the two compound nutating wheels 15 within the β-angle oblique ring groove on the inner wall of the rotating drum 36. (As shown...) Figure 3 As shown in the function block diagram on the right, compared to Figure 2 In the functional block diagram of Embodiment 1, since each torque amplifier group has an additional stage of gear reduction transmission, the reduction ratio of the entire reducer is increased. Therefore, under the same motor output power, the size of the dual-head motor 34 can be reduced accordingly. Figure 3 The AA cross-sectional view in the figure provides a schematic diagram of the corresponding structure.

[0031] Example 3

[0032] like Figure 4 As shown, this embodiment provides a self-balancing dual-parallel composite nutator reducer with a combined motor drive housing output. The reducer is also compactly composed of a high-speed moving component, a low-speed moving component, and a stationary component in the radial and axial directions. The high-speed moving component consists of an outer rotating cylinder 63 (with a β-angle oblique ring groove formed by multiple parts on its outer wall) integrated with the outer rotor of the combined motor, which has a permanent magnet 62 embedded in it, two high-speed moving rings of a bidirectional thrust ball bearing 67, and a ball-and-cage assembly. Two sets are arranged axially symmetrically. They are supported on two fixed end covers 55 and a central partition 76 by four sets of sealed angular contact ball bearings 56, which also separate the motor housing from the reducer housing. The low-speed moving component consists of two composite nutating wheels 74 integrated with the low-speed moving ring 75 of the double-direction thrust ball bearing 67, and a rotatable housing 51 connected via drum-shaped toothed splines 73 and 71 on its outer circumference. A pair of tapered roller bearings 52 support the housing 51 on two fixed end caps 55 and are pre-tightened by screws 54 via two ring plates 53. The two drum-shaped splined toothed rings 71 are fixed to the housing 51 by screws 72 and are axially positioned by two sleeves 70. The stationary component consists of a hollow stator shaft 59 of the assembled motor, end caps 55 with integrated tapered stationary toothed rings 68 fixed to both ends of the hollow stator shaft 59 by two nuts 60, and a central partition 76 with integrated two tapered stationary toothed rings 57 fixed to the middle of the hollow stator shaft 59 by screws 77.

[0033] like Figure 4As shown, the power cord 58 passes through the wall hole of the left end cover 55 and connects in series with the windings of two motor stators 61 with the same structure and electrical parameters, forming a combined motor. The two outer rotating cylinders 63, which are separated by the middle partition 76 and have the same structure and electrical parameters and are coaxial, rotate in the same direction and at high speed. This drives two composite nutation wheels 74, which are embedded in the β-angle inclined ring groove on the outer wall of the outer rotating cylinder 63 via the double-direction thrust ball bearing 67. On any axial section passing through the line connecting their centers, they oscillate in opposite directions around their respective centers with the same angular velocity. On the outer walls of the two outer rotating cylinders 63, a nutation angle β is formed by the combination of radial bearing housing rings 64 and two thrust bearing housing rings 66 that are circumferentially 180° apart and axially opposite, with one end having a β-angle inclined surface, through a flat key 65.

[0034] like Figure 4 As shown, on the four end faces of the two composite nutator wheels 74, planar moving gear rings 69 with the same module and tooth profile and an inner cone angle of 180° are integrated. Each of them has a small number of teeth that mesh with the corresponding portion of teeth on the conical fixed gear rings 68 on the two end covers 55, which have the same module and tooth profile but slightly fewer teeth, and on the conical fixed gear rings 57 on both sides of the middle partition 76, with a small tooth difference that is 180° apart in both directions and axially symmetrical. Figure 4 As shown in the functional block diagram on the right, the high-speed, low-torque input from the combined motor is proportionally amplified in parallel. Four 180°-2β cone-angled fixed gear rings 68 and 57 are arranged in pairs, with their cone surfaces facing each other and symmetrically parallel. When the difference in the number of teeth between the planar moving gear ring 69 and the cone-shaped fixed gear rings 68 and 57 is odd, the two cone-shaped fixed gear rings 57 on the partition 76 and the cone-shaped fixed gear rings 68 on the end caps 55 need to be staggered by half a tooth in the circumferential direction for installation and fixation. When the difference in the number of teeth is even, no staggered tooth installation is required in the circumferential direction. Similar to Embodiment 1, because the two composite nutating wheels 74 swing symmetrically in opposite directions around their respective centers, the forces acting on all symmetrical components within the reducer, except for the circumferential force that generates the same-direction rotational torque, cancel each other out and automatically balance. Therefore, the reducer is not affected by time-varying rotational torsional vibrations from the outside.

[0035] Depend on Figure 4It is understood that the compound nutating wheel 74 in this embodiment has three functions: its inner circular surface is integrated with the low-speed moving ring 75 of the bidirectional thrust ball bearing 67 to realize the low-speed oscillation input of the nutating wheel; its two end faces are integrated with planar moving gear rings 69 of the same module and tooth shape, which respectively mesh with the corresponding surfaces of the conical fixed gear ring 68 integrated on an end cover 55 and the conical fixed gear ring 57 integrated on the middle partition 76, and the corresponding parts of the gear teeth in the circumferential direction with a small tooth difference, realizing the simultaneous parallel deceleration of two sets of nutating transmissions, so that the compound nutating wheel 74 generates low-speed rotation; the torque amplified by the meshing of the gear teeth of the two sets of nutating transmissions is superimposed on the mid-section of the compound nutating wheel 74, and is output by the outer casing 51 through the variable stiffness connection between the drum-shaped spline teeth 73 on its outer circular surface and the drum-shaped spline gear ring 71 on the outer casing 51.

[0036] Example 4

[0037] Figure 5 This is a schematic diagram of the self-balancing dual-parallel compound nutating wheel reducer with dual-head motor drive housing output in Embodiment 4 of the present invention. The essential difference between this and Embodiment 3 lies not only in the drive motor, but also in the integration of an inner conical moving gear ring with an angle less than 180° on both ends of the compound nutating wheel. For ease of demonstration and description, all... Figure 5 Zhongyu Figure 4 In Example 3, the components with the same structure and function have the same numbering, and their identical functions and structures will not be described in detail again.

[0038] like Figure 5 As shown, the high-speed moving component in this embodiment consists of a rotating cylinder 86 with a radial toothed ring on its inner circular surface (its outer wall has a β-angle oblique ring groove formed by multiple parts), two high-speed moving rings of a double-direction thrust ball bearing 67, and a ball-cage assembly. Two sets are arranged axially symmetrically. They are supported on two fixed end covers 80 and a central partition 85 by four sets of sealed angular contact ball bearings 56, which also separate the motor compartment from the reducer compartment. The low-speed moving component consists of two composite nutator wheels 90 integrated with the low-speed moving ring 91 of the double-direction thrust ball bearing 67, and a rotatable housing 51 connected by drum-shaped toothed splines 89 and 71 on its outer circular surface. A pair of tapered roller bearings 52 support the housing 51 on the two fixed end covers 80 and are pre-tightened by screws 54 through two ring plates 53. The two drum-shaped spline toothed rings 71 are fixed to the housing 51 by screws 72 and are axially positioned by two sleeves 70. The stationary components consist of a hollow shaft 82 with a tapered fixed gear ring 87 that is fixed to the dual-head motor 85 by screws 93 and 94, an end cap 80 with a tapered fixed gear ring 87 that is fixed to both ends of the hollow shaft 82 by two nuts 60, and a middle partition 92 with two tapered fixed gear rings 81 that is fixed to the middle of the hollow shaft 82 by screws 77.

[0039] like Figure 5As shown, the power cable 83 of the dual-head motor 85 passes through the wall hole of the irregular hollow shaft 82 and connects to an external power source. The gears 84 on the output shafts at both ends of the dual-head motor 85 mesh with the radial gear rings on the inner circular surfaces of the two rotating drums 86. After being transmitted through a single-stage gear in a parallel shaft manner, they drive the two compound nutating wheels 90 in the β-angle oblique ring groove on the outer wall of the rotating drum 86 to work. Figure 5 As shown in the function block diagram on the right, compared to Figure 4 The functional block diagram of Embodiment 3 shows that, since each torque amplifier in this embodiment also adds a gear reduction transmission stage, the reduction ratio of the entire reducer is increased. Therefore, under the same motor output power, the volume of the dual-head motor 85 can be reduced accordingly. Compared to... Figure 3 In the second embodiment, the dual-head motor 85 is placed inside the reducer.

[0040] Depend on Figure 5 It is understood that the compound nutating wheel 90 in this embodiment has three functions: its inner circular surface is integrated with the low-speed moving ring 91 of the bidirectional thrust ball bearing 67 to realize the low-speed oscillation input of the nutating wheel; its two end faces are integrated with inner conical moving gear rings 88 of the same module and tooth shape, which respectively mesh with the corresponding surfaces of the conical fixed gear ring 87 integrated on an end cover 80 and the conical fixed gear ring 81 integrated on the middle partition 92, and perform small tooth difference meshing of the corresponding parts of the gear teeth in the circumferential direction with a difference of 180°, realizing the simultaneous parallel deceleration of two sets of nutating transmissions, so that the compound nutating wheel 90 generates low-speed rotation; the torque amplified by the meshing of the gear teeth of the two sets of nutating transmissions is superimposed on the mid-section of the compound nutating wheel 90, and is output by the outer casing 51 through the variable stiffness connection between the drum-shaped spline teeth 89 on its outer circular surface and the drum-shaped spline gear ring 71 on the outer casing 51.

[0041] Four conical fixed gear rings 87 and 81 with cone angles less than 180°-2β are arranged in pairs with their cone surfaces facing each other and symmetrically parallel. When the difference in the number of teeth between the inner conical moving gear ring 88 and the conical fixed gear rings 87 and 81 is odd, the two conical fixed gear rings 81 on the partition 92 and the conical fixed gear rings 87 on the end caps 80 need to be staggered by half a tooth in the circumferential direction for installation and fixation. When the difference in the number of teeth is even, no staggered tooth installation is required in the circumferential direction. Similar to Embodiment 3, because the two compound nutwheels 90 swing symmetrically in opposite directions around their respective centers, the forces acting on all symmetrical components in the reducer, except for the circumferential force that generates the same rotational torque, cancel each other out and are automatically balanced. Therefore, the reducer is not affected by time-varying rotational torsional vibrations from the outside.

[0042] The foregoing has described four preferred embodiments of the present invention in detail. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A self-balancing dual-parallel compound nutator reducer, characterized in that, Two parallel compound nutator drive components with identical structural parameters are arranged axially symmetrically. The two compound nutator wheels are driven to oscillate symmetrically around their respective centers by the double inner or double outer rotors of the combined motor or the gear pairs at both ends of the double-headed motor. The high-speed, low-torque input is proportionally amplified in parallel by the meshing of four sets of nutator drive wheels with the same tooth profile, module, and tooth number difference in each pair. The amplified torque in the same direction is superimposed on the mid-section of the compound nutator wheels in pairs, and then output outward through the drum-shaped tooth splines of the same structure on the inner hole or outer surface of the two compound nutator wheels, and then superimposed again by a rotating hollow shaft or housing. The radial and axial external forces at the output end are borne by a pair of angular contact ball bearings or a pair of tapered roller bearings supporting the hollow shaft or housing between two fixed end covers. On the four end faces of the two compound nutating wheels, there are integrated inner conical moving gear rings with the same module and tooth profile. Each of them has a portion of the gear teeth that are in mesh with the corresponding portion of the gear teeth on the conical fixed gear rings with the same module on the two end covers and the conical fixed gear rings with the same module on both sides of the middle partition, with a small tooth difference meshing that is 180° apart in both directions and axially symmetrical. The nutation motion of the composite nutation wheel is generated by the nutation angle β oblique ring groove formed by the assembly of various parts on the inner or outer wall of the rotating drum through a two-way thrust ball bearing.

2. The self-balancing dual-parallel composite nutating wheel reducer as described in claim 1, characterized in that, The reducer is composed of high-speed and low-speed moving parts and stationary parts in a compact radial and axial configuration. The high-speed moving part consists of a rotating drum or a rotating drum with radial gear integrated with the rotor of the combined motor, two high-speed moving rings of a double-direction thrust ball bearing, and a ball-cage assembly. Two sets are arranged symmetrically in the axial direction and supported on the stationary part by four sets of sealed angular contact ball bearings, which also separate the motor compartment from the reducer compartment. The low-speed moving part consists of two compound nutating wheels integrated with the low-speed moving rings of the double-direction thrust ball bearing, and a rotating hollow shaft or housing connected by a drum-shaped tooth spline on its inner hole or outer surface. When the compound nutating wheels are working, they are in a low-speed oscillating motion state, while the hollow shaft or housing only performs low-speed rotational motion. The stationary components consist of the stator housing or hollow stator shaft of the assembled motor, or the housing or hollow shaft of the fixed dual-head motor; end caps with integrated conical stator gear rings fixed at both ends of the stator housing or hollow stator shaft of the assembled motor, or the housing or hollow shaft of the fixed dual-head motor; and a middle partition plate fixed in the middle of the stator housing or hollow stator shaft of the assembled motor, or the housing or hollow shaft of the fixed dual-head motor, with conical stator gear rings integrated on both sides.

3. The self-balancing dual-parallel composite nutating wheel reducer as described in claim 1 or 2, characterized in that, Two motor stator windings with the same structure and electrical parameters are connected in series or in parallel to form a composite motor. Two inner or outer rotating drums with the same structure and electrical parameters and coaxiality are separated by a partition plate and rotate in the same direction and at high speed. This drives two composite nutating wheels embedded in the assembled β-angle oblique ring grooves on the inner or outer walls of their respective rotating drums via bidirectional thrust ball bearings. On any axial section passing through the line connecting their centers, they oscillate in opposite directions around their respective centers with the same angular velocity.

4. The self-balancing dual-parallel composite nutating wheel reducer as described in claim 1 or 2, characterized in that, A pair of gears with identical structural parameters, located on the output shafts of a dual-head motor placed outside or inside the two rotating drums, mesh with radial gears with identical structural parameters on the outer or inner surfaces of the two rotating drums. Through a single-stage gear transmission in a parallel-axis manner, the two rotating drums rotate in the same direction and at high speed, driving two composite nutation wheels, which are embedded in β-angle oblique ring grooves on the inner or outer walls of their respective rotating drums via bidirectional thrust ball bearings, to oscillate axially in opposite directions and symmetrically around their respective centers.

5. The self-balancing dual-parallel composite nutating wheel reducer as described in claim 1 or 2, characterized in that, Four conical fixed gear rings with a cone angle of less than or equal to 180°-2β are arranged in parallel with their cone surfaces facing each other in a symmetrical manner. When the difference in the number of teeth between two parallel compound nutator drive components with the same structural parameters is odd, the two conical fixed gear rings on the partition plate and the conical fixed gear rings on the end caps need to be staggered by half a tooth in the circumferential direction for installation and fixation. When the difference in the number of teeth between the two drive components is even, no staggered tooth installation is required in the circumferential direction. Due to the electromechanical integrated optimized reducer structure, there are four sets of gear teeth meshing and reducing speed at the same time. The partition plate and the two conical fixed gear rings, the two compound nutator wheels and the low-speed moving rings of the double-direction thrust ball bearings and the drum spline teeth, the rotor and the drum of the combined motor are all integrated into one unit. This makes the reducer self-powered and has the characteristics of compact radial and axial structure, large load-bearing capacity, self-balancing internal forces, no vibration impact on the outside, good rigidity, high transmission accuracy and transmission efficiency.

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