Self-balancing double-parallel type composite nutation wheel speed reducer

Abstract

A mechanical and electrical integrated parallel type composite nutation wheel speed reduction transmission thought is applied, two parallel type composite nutation wheel transmission assemblies with the same structural parameters are axially and symmetrically arranged, and two motor stator windings with the same structure and electrical parameters are connected in series or in parallel; therefore, the self-balancing double-parallel type composite nutation wheel speed reducer which rotates synchronously in the same direction is formed. On any axial cross section passing through the center connecting line of the two composite nutation wheels, the composite nutation wheels swing reversely and symmetrically around the axial directions of the centers of the composite nutation wheels, except for all circumferential forces generating the same-direction rotating torque, acting force borne by all symmetrical parts in the speed reducer is balanced, and no vibration influence exists on the outside. Due to the fact that the four sets of gear teeth are meshed at the same time for speed reduction, and the middle partition disc, the two conical surface fixed gear rings, the composite nutation wheel, the low-speed moving ring of the two-way thrust ball bearing and the drum-shaped spline teeth for outputting torque are integrated, the speed reducer has the advantages of being compact in structure, large in bearing capacity, good in rigidity, high in transmission precision and transmission efficiency and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical transmission, and in particular relates to a self-balancing double-parallel compound nutating wheel reducer. Background Art

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

[0003] RV reducers also have the advantages of large reduction ratio, coaxial transmission, high rigidity, high load capacity and higher transmission efficiency than harmonic reducers, but they are difficult to miniaturize due to their complex structure, many parts, large size and weight, and high cost. They are currently mainly used in heavy-loaded parts such as the arms and waist of industrial robots. Although planetary gear reducers have high transmission efficiency, coaxial transmission, and high rigidity, they have a small single-stage reduction ratio and low transmission accuracy due to the existence of tooth gaps.

[0004] The working principle of the nutating reducer is essentially the same as that of the harmonic reducer. It uses the axial centering swing of the nutating wheel to realize the engagement of the small tooth difference between the moving gear ring on it and the fixed gear ring with slightly fewer teeth on the fixed rigid wheel, so as to achieve the purpose of a large reduction ratio. Due to the large number of meshing teeth and no or few flexible working parts, it has the advantages of high rigidity, simple structure, coaxial transmission, large load-bearing capacity, and high transmission accuracy; but due to the axial centering swing of the nutating wheel, it has the disadvantages of periodic rotational torsional vibration and low transmission efficiency, which makes it unsuitable for high-speed input motion conditions. At present, the application scenarios are limited and most of them are single components. Series and face-to-face parallel reducer solutions have been proposed and applied in small quantities.

[0005] The invention patent application "Mechatronic parallel composite nutating wheel reducer" (publication number: CN 118959555 A) proposes six mechatronic parallel composite nutating wheel reducers, which combine the swing input nutating wheels of two nutating transmission components into one, and make axial centering swing in the inclined ring raceway groove on the high-speed rotor of the motor through a group of outwardly extending swing rod bearings on the outer (or inner) circular side of the middle section of the composite nutating wheel. The planar moving gear rings on the two end surfaces of the composite nutating wheel and the conical fixed gear rings on the end covers of the motor stator are engaged with a small tooth difference at the side ends with a difference of 180° to form a nutating transmission, so that half of the motor input torque is amplified by two groups of back-to-back parallel nutating components in the same proportion; and the rotation output is through the variable stiffness angle torque transmission connection member with high circumferential stiffness and low axial stiffness on the inner hole (or outer cylindrical surface) of the composite nutating wheel. The bearing capacity, rigidity and efficiency of the nutating reducer are improved, making the structure more compact, but the problem of the periodic rotational torsional vibration of the parallel composite nutating wheel reducer being affected by the external environment has not been solved. Summary of the invention

[0006] In view of the defects of the prior art inventions, the present invention proposes four self-balancing double parallel compound nutating wheel reducers. Based on the parallel compound nutating wheel reduction transmission concept proposed in the invention patent application CN 118959555 A, two parallel compound nutating wheel transmission components with the same structural parameters are arranged axially symmetrically, and two motor stator windings with the same structure and electrical parameters are connected in series or in parallel to form a split motor, so that the two inner rotating drums or outer rotating drums with the same structure and electrical parameters and coaxial separated by a middle partition plate rotate in the same direction and synchronously at high speed (or use the gear pairs at both ends of the double-headed motor to make the two rotating drums rotate in the same direction and synchronously at high speed in a parallel shaft gear transmission mode), drive the two compound nutating wheels, and perform opposite axial swings around their respective centers at the same angular velocity on any axial section passing through the center line of the two compound nutating wheels. Therefore, in addition to generating various circumferential forces that rotate in the same direction as the torque, this invention utilizes the principle that the forces acting on the symmetrical components in the reducer cancel each other out and balance themselves, thereby successfully eliminating the stubborn problem of the nutating reducer that has always been affected by periodic rotational torsional vibration.

[0007] The reducer is composed of high-speed moving parts, low-speed moving parts and static parts in a compact manner in radial and axial directions; the high-speed moving parts are composed of a rotating drum integrated with the rotor embedded with permanent magnets in the split motor or a rotating drum with radial gears (the inner wall or outer wall of both rotating drums is equipped with an oblique ring groove with the same nutation angle β by combining multiple parts), two high-speed moving rings of a bidirectional thrust ball bearing and a ball-cage assembly, and there are two groups of them arranged axially symmetrically. They are supported on the static parts through four sets of sealed angular contact ball bearings, and the motor cabin is separated from the reducer cabin. The low-speed moving parts are composed of two composite nutating wheels integrated with the low-speed moving ring of the bidirectional thrust ball bearing, and a rotatable hollow shaft or housing connected through the drum-shaped tooth spline on its inner hole or outer cylindrical surface, and are supported on two fixed end covers by a pair of angular contact ball bearings or a pair of tapered roller bearings. The stationary part is composed of the stator shell or stator shaft of the split motor (or the shell or hollow shaft of the fixed double-headed motor), the end covers fixed at both ends with integrated conical fixed gear rings, and the middle partition plate fixed in the middle with two integrated conical fixed gear rings.

[0008] The composite nutating wheel and its transmission assembly have three functions: first, as the low-speed moving ring of the bidirectional thrust ball bearing, the rotational motion of the two high-speed moving rings of the bidirectional thrust ball bearing is converted into a low-speed swing around its own center due to the nutation angle β oblique ring grooves assembled on the inner and outer walls of the rotating drum; second, through the inner conical moving gear rings with the same module and tooth shape integrated on the end faces of both sides, they are respectively engaged with the corresponding surfaces of the conical fixed gear ring integrated on an end cover and the conical fixed gear ring integrated on the middle partition plate, and the corresponding partial gear teeth are meshed in the direction of 180° difference in the circumferential direction, and the module of the two conical fixed gear rings is The number and tooth shape are the same as those of the movable gear ring, but the number of teeth is slightly less than that of the movable gear ring. Since the movable and static gear rings are meshed with a small tooth difference, two sets of nutating reduction transmission teeth are meshed on one compound nutating wheel, causing it to rotate at a low speed, which is superimposed with the above-mentioned low-speed swing to form a nutating motion; thirdly, the torque amplified by the meshing of the two sets of nutating transmission teeth is superimposed on the middle section of the compound nutating wheel, connected through the drum-shaped tooth spline on its inner hole or outer cylindrical surface, and output by a rotatable hollow shaft or outer shell, while the difference axial swing torque is transmitted to the static component through the supporting bearing.

[0009] For the parallel compound nutating wheel transmission assembly with two axisymmetric arrangements, there are four groups of nutating transmission gear teeth with the same tooth shape, module and number of teeth on the four end faces of the two compound nutating wheels, which are meshed with small tooth difference of two or more axes with a difference of 180° and symmetric, and the high speed and small torque input by the split motor or double-headed motor are amplified in parallel with the same proportion; the amplified same-direction torque is superimposed on the middle section of the compound nutating wheel in pairs, and then output outward through the torque output drum-shaped tooth spline with the same structure on the inner hole or outer circle of the two compound nutating wheels, and then superimposed again through a rotating hollow shaft or shell; the radial and axial external forces outside 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 shell between the two fixed end covers. The four conical fixed gear rings with a diameter of less than or equal to 180°-2β in the self-balancing double parallel compound nutating wheel reducer are arranged in parallel with each other in pairs of cone surfaces, and are arranged in parallel with the axis symmetry.

[0010] When the difference in the number of teeth of two parallel compound nutating wheel transmission assemblies with the same structural parameters is an odd number, the two conical fixed gear rings on the spacer and the conical fixed gear rings on the two end covers need to be installed and fixed by half a tooth in the circumferential direction; when the difference in the number of teeth of the above two transmission assemblies is an even number, there is no need to install them with staggered teeth in the circumferential direction; because there are four sets of gear teeth meshing for deceleration at the same time, and the middle spacer and the two conical fixed gear rings, the two compound nutating wheels and the low-speed moving rings and drum-shaped spline teeth of the bidirectional thrust ball bearing, the split motor rotor and the rotating drum are all integrated into one, so that 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 nutating wheel reducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the structure of a mechatronic parallel compound nutating reducer with a single transmission component;

[0012] Figure 2 It is a structural schematic diagram of a preferred embodiment of the present invention - a self-balancing double parallel compound nutating wheel reducer with split motor drive shaft output;

[0013] Figure 3 It is a structural schematic diagram of a self-balancing dual-parallel composite nutating wheel reducer with dual-head motor drive shaft output of the present invention;

[0014] Figure 4 It is a structural schematic diagram of the self-balancing double-parallel composite nutating wheel reducer with split motor drive housing output of the present invention;

[0015] Figure 5 It is a structural schematic diagram of a self-balancing dual-parallel composite nutating wheel reducer output by a double-head motor drive shell of the present invention. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] In the following description, specific details such as specific internal technologies are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, and installation methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0018] Figure 1 The schematic diagram of the structure of the mechatronic parallel compound nutating reducer of the single transmission assembly in the preferred embodiment of the invention patent application CN 118959555 A is given. The nutating reducer is embedded in the motor, and the two end covers A4 integrated with the conical fixed gear ring A17 are fixedly connected to the motor housing A12 by screws A9. The hollow shaft A1 is supported on the two end covers A4 through a pair of angular contact bearings A3 and axially preloaded by two nuts A2; the two end surfaces of the compound nutating wheel A5 are integrated with a plane movable gear ring A16 with the same module and tooth shape. The module and tooth shape of the conical fixed gear ring A17 are the same as those of the plane movable gear ring A16, but the number of teeth Z of the conical fixed gear ring A17 is smaller than that of the plane movable gear ring A16. 2 Less than the number of teeth Z of the flat movable gear ring 16 1 The outer circle of the motor rotor A7 is embedded with a permanent magnet A10, and its inner circle has a β-angle oblique annular raceway groove due to the oblique end face sleeve A15, and is supported on the two end covers A4 through 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, the power line A8 is inserted through the side wall hole of the left end cover A4 and electrically connected to the motor stator A11. When the motor stator A11 is powered on and drives the rotor A7 to rotate at high speed, the outer rings of three or more guide needle bearings A13 evenly arranged on the outer circumference of the compound nutating wheel A5 through the pin shaft A14 roll at high speed in the β-angle bevel ring raceway groove on the inner circumference of the motor rotor A7, driving the compound nutating wheel A5 to make a centering axial swing. Since the planar moving gear rings A16 on the two end faces of the compound nutating wheel A5 are always meshed with the conical fixed gear rings of the two end covers A4 on both sides with a small tooth difference at a circumferential difference of 180°, the compound nutating wheel A5 is forced to rotate at a low speed in the circumferential direction at the same time, forming a nutating transmission, that is, the two nutating transmission components on the two end faces of the compound nutating wheel A5 are as shown in FIG. Figure 1As shown in the functional block diagram on the right, it is actually a back-to-back parallel amplification of half of the motor input torque. After the two parallel amplified torques are superimposed on the middle section of the compound nutating wheel A5, they are output to the hollow shaft A1 through the drum spline A18 on its inner circle side and the middle part of the outer circle of the hollow shaft A1, and then drive the external connecting parts connected to the hollow shaft A1, while 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 nutating wheel A5 is subjected to opposite forces on the two end faces that differ by 180° in the circumferential direction, their axial forces can offset each other, but the time-varying rotational swing torque caused by the axial force is transmitted to the end cover A4 through the angular contact ball bearing A6; and the drum spline A18 only outputs the rotational motion of the compound nutating wheel A5 to the hollow shaft A1, and the radial and axial friction forces thereon can also offset each other, but the time-varying rotational swing torque caused by the radial and axial friction forces is transmitted to the end cover A4 through the angular contact ball bearing A3, so the mechatronic parallel compound nutating wheel reducer has the problem of periodic time-varying rotational torsional vibration affecting the outside.

[0021] In view of the above problems, the present invention will describe a self-balancing dual-parallel compound nutating wheel reducer in combination with embodiments.

[0022] Preferred embodiment 1

[0023] like Figure 2 As shown, this embodiment provides a self-balancing dual parallel compound nutating wheel reducer for the output of the split motor drive shaft. In this embodiment, the reducer is composed of high-speed moving parts, low-speed moving parts and static parts in a compact manner in the radial and axial directions. The high-speed moving parts are composed of an inner rotating cylinder 21 (on the inner wall of which there is a β-angle oblique annular groove assembled by multiple parts) integrated with the inner rotor of the split motor with a permanent magnet 5, two high-speed moving rings of a bidirectional thrust ball bearing 19 and a ball-cage assembly, and two groups are arranged axially symmetrically. They are supported on two fixed end covers 3 and a middle partition plate 22 through four sets of sealed angular contact ball bearings 7, and the motor compartment is separated from the reducer compartment. The low-speed moving part is composed of two composite nutating wheels 15 integrated with the low-speed moving ring 20 of the bidirectional thrust ball bearing 19, and a rotatable hollow shaft 10 connected via the drum-shaped tooth splines 13 and 12 on its inner hole surface. A pair of angular contact ball bearings 8 support the hollow shaft 10 on two fixed end covers 3 and are pre-tightened by two nuts 11. The static part is composed of the stator case 2 of the split motor, the end cover 3 with integrated conical fixed gear ring 14 fixed at both ends of the stator case 2 by screws 1, and the middle partition plate 22 with integrated two conical fixed gear rings 9 fixed in the middle of the stator case 2 by screws 24.

[0024] like Figure 2As shown, the power line 23 is inserted through the wall hole of the stator housing 2, and the windings of the two motor stators 4 with the same structure and electrical parameters are connected in parallel to form a combined motor; and the two inner rotating cylinders 21 with the same structure and electrical parameters and coaxial separated by the middle partition plate 22 rotate in the same direction and synchronously at high speed, driving the two composite nutating wheels 15 embedded in the β-angle oblique ring groove on the inner wall of the inner rotating cylinder 21 through the bidirectional thrust ball bearing 19, and swinging in the opposite direction around their respective centers at the same angular velocity on any axial section passing through the center line of them. On the inner walls of the two inner rotating cylinders 21, an oblique ring groove with the same nutation angle b is assembled by the radial bearing seat sleeve 17 and two thrust bearing seat sleeves 18 with one end having a β-angle oblique surface installed in the axial direction in the opposite direction and 180° apart in the circumferential direction, respectively through the flat key 6.

[0025] like Figure 2 As shown, on the four end faces of the two compound nutating wheels 15, there are integrated planar movable gear rings 16 with the same module and tooth shape and an internal cone angle of 180°, each of which has a small number of gear teeth, which are meshed with the conical fixed gear rings 14 on the two end covers 3 with the same module and tooth shape but slightly fewer teeth, and the corresponding part of the gear teeth on the same conical fixed gear rings 9 on both sides of the middle partition plate 22, with two or more axially symmetrical small tooth differences, as shown in FIG. Figure 2 As shown in the functional block diagram on the right, the high speed and low torque input of the combined motor are amplified in parallel at the same ratio. Figure 1 As can be seen from the functional block diagram on the right, this embodiment has an additional set of two torque amplifiers. The four conical fixed gear rings 14 and 9 with a cone angle of 180°-2β are arranged in parallel with each other in a symmetrical manner. When the difference in the number of teeth between the planar movable gear ring 16 and the conical fixed gear rings 14 and 9 is an odd number, the two conical fixed gear rings 9 on the spacer 22 and the conical fixed gear rings 14 on the two end covers 3 need to be installed and fixed by half a tooth in the circumferential direction; when the above-mentioned difference in the number of teeth is an even number, there is no need to install the circumferential teeth in a staggered manner. Because the axial swing of the two compound nutating wheels 15 around their respective centers is reversely symmetrical, the forces acting on all symmetrical parts in the reducer, except for the circumferential force that produces the same-direction rotating torque, all cancel each other out and automatically balance, so the reducer has no time-varying rotational torsional vibration effect on the outside.

[0026] Depend on Figure 2It is known that the four sides of the compound nutating wheel 15 have functional structures, and its outer cylindrical surface is integrated with the low-speed moving ring 20 of the bidirectional thrust ball bearing 19 to realize the low-speed swing input of the nutating wheel; the two end surfaces thereof are integrated with the plane moving gear ring 16 of the same modulus and tooth shape, which are respectively engaged with the corresponding surfaces of the conical fixed gear ring 14 integrated on an end cover 3 and the conical fixed gear ring 9 integrated on the middle partition plate 22, and the corresponding gear teeth in the directions of 180° different in the circumferential direction are meshed with a small tooth difference, thereby realizing the simultaneous parallel deceleration of two groups of nutating transmissions, so that the compound nutating wheel 15 produces low-speed rotation; the torque amplified by the meshing of the two groups of nutating transmission gear teeth is superimposed on the middle section of the compound nutating wheel 15, and is output by the rotatable hollow shaft 10 through the variable stiffness connection of the drum spline teeth 13 on its inner hole and the drum spline teeth 12 on the hollow shaft 10 with high circumferential stiffness and low axial stiffness. That is, the compound nutating wheel 15 has the triple functions of outer circle input, deceleration and amplification of torque at both end surfaces, superposition of two-way amplified torque at the middle section, and output of rotational torque through the inner hole and variable stiffness connection member.

[0027] Embodiment 2

[0028] A self-balancing dual parallel compound nutating wheel reducer driven by a double-headed motor shaft output Figure 3 As shown, the essential difference between the embodiment 1 and the embodiment 1 is only the difference in the driving motor. For the convenience of display and description, Figure 3 Zhongyu Figure 2 The components with the same structure and function in the first embodiment have the same number, and the same functions and structures will not be described in detail again.

[0029] like Figure 3 As shown, the high-speed moving part in this embodiment is composed of a rotating drum 36 with radial gears on the outer circle (on the inner wall of which there is an oblique annular groove with an angle of β formed by a plurality of parts), two high-speed moving rings of a bidirectional thrust ball bearing 19 and a ball-cage assembly, and two groups are arranged axially symmetrically. They are supported on two fixed end covers 31 and a middle partition plate 37 through four sets of sealed angular contact ball bearings 7, and the motor compartment is separated from the reducer compartment. The low-speed moving part is composed of two composite nutating wheels 15 integrated with the low-speed moving ring 20 of the bidirectional thrust ball bearing 19, and a rotatable hollow shaft 10 connected by drum-shaped tooth splines 13 and 12 on its inner hole 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 part consists of a housing 30 to which a double-headed motor 34 is fixed by screws 33 and 38, an end cover 31 fixed at both ends of the housing 30 by screws 1 and integrated with a conical fixed gear ring 14, and a partition plate 37 fixed in the middle of the housing 30 by screws 24 and integrated with two conical fixed gear rings 9.

[0030] like Figure 3As shown, the double-headed motor 34 is connected to an external power source through a power line 32 inserted through a wall hole of the housing 30. The gears 35 on the output shafts at both ends of the double-headed motor 34 mesh with the radial gears on the outer circumferential surfaces of the two rotating drums 36. After being transmitted through a primary gear in a parallel axis manner, the two compound nutating wheels 15 in the β-angled bevel annular groove on the inner wall of the rotating drum 36 are driven to work. Figure 3 As shown in the functional block diagram on the right, compared to Figure 2 In the functional block diagram of the first embodiment, since each set of torque amplifiers has an additional gear reduction transmission, the reduction ratio of the entire reducer is increased. Therefore, under the same motor output power, the volume of the double-headed motor 34 can be reduced accordingly. Figure 3 The AA cross-section diagram in FIG. 1 shows the corresponding structure.

[0031] Embodiment 3

[0032] like Figure 4 As shown, this embodiment provides a self-balancing double parallel compound nutating wheel reducer with output from a split motor drive housing. The reducer is also composed of high-speed moving parts, low-speed moving parts and static parts that are compact in diameter and axial direction. The high-speed moving parts are composed of an outer rotating cylinder 63 (on the outer wall of which there is a β-angle oblique annular groove assembled by multiple parts) integrated with the outer rotor with a permanent magnet 62 in the split motor, two high-speed moving rings of a bidirectional thrust ball bearing 67 and a ball-cage assembly, and two groups are arranged axially symmetrically. They are supported on two fixed end covers 55 and a middle partition plate 76 through four sets of sealed angular contact ball bearings 56, and the motor compartment is separated from the reducer compartment. The low-speed moving part is composed of two composite nutating wheels 74 integrated with the low-speed moving ring 75 of the bidirectional thrust ball bearing 67, and a rotatable housing 51 connected via drum-shaped tooth splines 73 and 71 on its outer circumferential surface. A pair of tapered roller bearings 52 supports the housing 51 on two fixed end covers 55 and is pre-tightened by screws 54 through two ring plates 53. Two drum-shaped spline gear rings 71 are fixed to the housing 51 by screws 72 and axially position the pair of tapered roller bearings 52 via two sleeves 70. The stationary part is composed of a hollow stator shaft 59 of the split motor, an end cover 55 with integrated conical fixed gear rings 68 fixed to both ends of the hollow stator shaft 59 by two nuts 60, and a middle partition plate 76 with integrated two conical fixed gear rings 57 fixed to the middle of the hollow stator shaft 59 by screws 77.

[0033] like Figure 4As shown, the power line 58 is inserted through the wall hole of the left end cover 55, and the windings of the two motor stators 61 with the same structure and electrical parameters are connected in series to form a combined motor; and the two outer rotating cylinders 63 with the same structure and electrical parameters and coaxial separated by the middle partition plate 76 rotate in the same direction and synchronously at high speed, driving the two composite nutating wheels 74 embedded in the β-angle oblique ring groove on the outer wall of the outer rotating cylinder 63 through the bidirectional thrust ball bearing 67, and swinging in the opposite direction around their respective centers at the same angular velocity on any axial section passing through the center line of them. On the outer walls of the two outer rotating cylinders 63, an oblique ring groove with the same nutation angle β is assembled by a radial bearing seat ring 64 and two thrust bearing seat rings 66 with a circumferential difference of 180° and axially opposite installation, one end of which is a β-angle oblique surface.

[0034] like Figure 4 As shown, on the four end faces of the two compound nutating wheels 74, there are integrated planar movable gear rings 69 with the same module and tooth shape and an internal cone angle of 180°. They each have a small number of gear teeth, which are meshed with the conical fixed gear rings 68 with the same module and tooth shape but slightly fewer teeth on the two end covers 55, and the corresponding part of the gear teeth on the same conical fixed gear rings 57 on both sides of the middle partition plate 76, with two or more axially symmetrical small tooth differences, as shown in FIG. Figure 4 As shown in the functional block diagram on the right, the high-speed and low-torque input of the combined motor are amplified in parallel in the same proportion. The four conical fixed gear rings 68 and 57 with a cone angle of 180°-2β are arranged in parallel with each other in a symmetrical manner. When the difference in the number of teeth between the plane movable gear ring 69 and the conical fixed gear rings 68 and 57 is an odd number, the two conical fixed gear rings 57 on the partition plate 76 and the conical fixed gear rings 68 on the two end covers 55 need to be installed and fixed by half a tooth in the circumferential direction; when the above-mentioned difference in the number of teeth is an even number, there is no need to install the circumferential teeth in a staggered manner. As in the first embodiment, because the axial swing of the two composite nutating wheels 74 around their respective centers is reversely symmetrical, the forces acting on all symmetrical parts in the reducer, except for the circumferential force that produces the same-direction rotating torque, all cancel each other out and automatically balance, so the reducer has no time-varying rotational torsional vibration effect on the outside.

[0035] Depend on Figure 4It is known that the triple functions of the compound nutating wheel 74 in this embodiment are: its inner circumferential surface is integrated with the low-speed moving ring 75 of the bidirectional thrust ball bearing 67 to realize the low-speed swing input of the nutating wheel; the two end surfaces thereof are integrated with the plane moving gear ring 69 of the same module and tooth shape, which are respectively engaged 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 plate 76, and the corresponding parts of the gear teeth in the directions 180° different in the circumferential direction are engaged with a small tooth difference, thereby realizing the simultaneous parallel deceleration of two groups of nutating transmissions, so that the compound nutating wheel 74 produces low-speed rotation; the torque amplified by the meshing of the two groups of nutating transmission gear teeth is superimposed on the middle section of the compound nutating wheel 74, and is output by the shell 51 through the drum spline teeth 73 on its outer circumferential surface and the variable stiffness connection of the drum spline gear ring 71 on the shell 51.

[0036] Embodiment 4

[0037] Figure 5 This is a schematic diagram of the structure of the self-balancing dual parallel compound nutating wheel reducer with double-headed motor drive shell output in the fourth embodiment of the present invention. The essential difference from the third embodiment is not only the difference in the drive motor, but also the internal conical dynamic gear ring with an angle less than 180° integrated on both end surfaces of the compound nutating wheel. For the convenience of display and description, all Figure 5 Zhongyu Figure 4 The parts with the same structure and function in the third embodiment have the same number, and the same functions and structures will not be described in detail again.

[0038] like Figure 5 As shown, the high-speed moving part in this embodiment is composed of a rotating drum 86 with a radial gear ring on the inner circumference (with a β-angled annular groove assembled by multiple parts on the outer wall), two high-speed moving rings of a bidirectional thrust ball bearing 67 and a ball-cage assembly, and two groups are arranged axially symmetrically. They are supported on two fixed end covers 80 and a middle partition plate 85 through four sets of sealed angular contact ball bearings 56, and the motor compartment is separated from the reducer compartment. The low-speed moving part is composed of two composite nutating wheels 90 integrated with the low-speed moving ring 91 of the bidirectional thrust ball bearing 67, and a rotatable housing 51 connected through drum-shaped tooth splines 89 and 71 on its outer circumference. A pair of tapered roller bearings 52 supports the housing 51 on the two fixed end covers 80 and is pre-tightened by screws 54 through two ring plates 53. Two drum-shaped spline gear rings 71 are fixedly connected to the housing 51 by screws 72, and the pair of tapered roller bearings 52 are axially positioned through two sleeves 70. The stationary part consists of a special-shaped hollow shaft 82 to which a double-headed motor 85 is fixed by screws 93 and 94, an end cover 80 with integrated conical fixed gear rings 87 fixed at both ends of the special-shaped hollow shaft 82 by two nuts 60, and a middle partition plate 92 with integrated two conical fixed gear rings 81 fixed in the middle of the special-shaped hollow shaft 82 by screws 77.

[0039] like Figure 5As shown, the power cord 83 of the double-headed motor 85 passes through the wall hole of the special-shaped hollow shaft 82 and is connected to an external power source. The gears 84 on the output shafts at both ends of the double-headed motor 85 mesh with the radial gear rings on the inner surfaces of the two rotating drums 86, and after being transmitted through a primary gear in a parallel axis manner, the two compound nutating wheels 90 in the β-angle oblique annular groove on the outer wall of the rotating drum 86 are driven to work. Figure 5 As shown in the functional block diagram on the right, compared to Figure 4 The functional block diagram of the third embodiment of the present invention shows that each set of torque amplifiers in the present embodiment also adds a gear reduction transmission, thereby increasing the reduction ratio of the entire reducer. Therefore, under the condition of the same motor output power, the volume of the double-headed motor 85 can be reduced accordingly. Figure 3 In the second embodiment, the double-headed motor 85 of this embodiment is placed inside the reducer.

[0040] Depend on Figure 5 It is known that the triple functions of the compound nutating wheel 90 in this embodiment are: its inner circumferential surface is integrated with the low-speed moving ring 91 of the bidirectional thrust ball bearing 67 to realize the low-speed swing input of the nutating wheel; the inner conical moving gear ring 88 with the same module and tooth shape is integrated on its two end surfaces, and is respectively engaged 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 plate 92, and the corresponding parts of the gear teeth in the directions 180° different in the circumferential direction are engaged with a small tooth difference, thereby realizing the simultaneous parallel deceleration of two groups of nutating transmissions, so that the compound nutating wheel 90 produces low-speed rotation; the torque amplified by the meshing of the two groups of nutating transmission gear teeth is superimposed on the middle section of the compound nutating wheel 90, and is output by the shell 51 through the drum spline teeth 89 on its outer circumferential surface and the variable stiffness connection of the drum spline gear ring 71 on the shell 51.

[0041] The four conical fixed gear rings 87 and 81 with a cone angle less than 180°-2β are arranged in parallel with each other in a symmetrical manner. When the difference in the number of teeth between the inner conical movable gear ring 88 and the conical fixed gear rings 87 and 81 is an odd number, the two conical fixed gear rings 81 on the spacer 92 and the conical fixed gear rings 87 on the two end covers 80 need to be installed and fixed by half a tooth in the circumferential direction; when the difference in the number of teeth is an even number, there is no need to install the circumferential teeth in a staggered manner. As in the third embodiment, because the axial swing of the two composite nutating wheels 90 around their respective centers is reversely symmetrical, the forces acting on all symmetrical parts in the reducer, except for the circumferential force that generates the same-direction rotating torque, all cancel each other out and automatically balance, so the reducer has no time-varying rotational torsional vibration effect on the outside.

[0042] Four preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. Self-balancing dual parallel compound nutating wheel reducer, characterized in that: Two parallel compound nutating wheel transmission components with the same structural parameters are arranged axially symmetrically, and the double inner or double outer rotors of the split motor, or the gear pairs at both ends of the double-headed motor, drive the two compound nutating wheels to perform axial swings in opposite directions and symmetrically around their respective centers; the input high-speed small torque is amplified in parallel with the same proportion by utilizing the meshing of four groups of nutating transmission wheel teeth with the same tooth shape, module and tooth number difference in the two transmission components; the amplified same-direction torque is superimposed on the middle section of the compound nutating wheel in pairs, and then output outwardly after being superimposed again through the drum-shaped tooth splines with the same structure on the inner holes or outer circumferential surfaces of the two compound nutating wheels through a rotating hollow shaft or shell; the radial and axial external forces outside 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 shell between the two fixed end covers.

2. The self-balancing dual parallel compound nutating wheel reducer according to claim 1, characterized in that: The reducer is composed of high-speed and low-speed moving parts and static parts compactly arranged in radial and axial directions; the high-speed moving part is composed of a drum integrated with the rotor embedded with permanent magnets in the split motor or a drum with radial gears (the inner or outer wall of both drums is equipped with an oblique ring groove with a nutation angle β), two high-speed moving rings of a bidirectional thrust ball bearing and a ball-cage assembly, two groups of which are arranged axially symmetrically and supported on the static parts by four sets of sealed angular contact ball bearings, with the motor cabin and the reducer cabin being separated; the low ... The low-speed moving ring of the bidirectional thrust ball bearing is composed of two integrated composite nutating wheels and a rotating hollow shaft or outer shell connected by the drum-shaped tooth spline on its inner hole or outer surface. The former is in a low-speed pendulum motion state when working, and the latter only performs low-speed rotation motion; the static part is composed of the stator shell or hollow stator shaft of the split motor (or the shell or hollow shaft of the fixed double-head motor), the end covers fixed at both ends thereof with integrated conical fixed gear rings, and the middle partition plate fixed in the middle and integrated with conical fixed gear rings on both sides.

3. The self-balancing dual parallel compound nutating wheel reducer according to 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 combined motor, so that the two inner or outer rotating drums with the same structure and electrical parameters and coaxial separated by a middle partition plate rotate in the same direction and synchronously at high speed, driving two compound nutating wheels embedded in the assembled β-angle oblique ring grooves on the inner or outer walls of each rotating drum via a bidirectional thrust ball bearing to perform axial swings in opposite directions around their respective centers at the same angular velocity on any axial section passing through the line connecting their centers.

4. The self-balancing dual parallel compound nutating wheel reducer according to claim 1 or 2, characterized in that: A pair of gears with the same structural parameters on the output shafts at both ends of the double-headed motor placed outside or inside the two rotating drums are meshed with radial gears with the same structural parameters on the outer or inner surfaces of the two rotating drums. The two rotating drums are rotated in the same direction and synchronously at high speed through a first-stage gear transmission in a parallel axis manner, driving two compound nutating wheels embedded in β-angle oblique ring grooves on the inner or outer walls of each rotating drum through a bidirectional thrust ball bearing to perform opposite and symmetrical axial swings around their respective centers.

5. The self-balancing dual parallel compound nutating wheel reducer according to claim 1 or 2, characterized in that: 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 shape. They each have a small number of teeth, which mesh with the conical fixed gear rings on the two end covers with the same module and tooth shape but slightly fewer teeth, and the corresponding part of the gear teeth on the same conical fixed gear rings on both sides of the middle partition plate, with a small tooth difference of 180° in two or three directions and symmetrically amplified in parallel the high-speed and low-torque input by the split motor or the double-headed motor in the same proportion. Because the axial swings of the two compound nutating wheels around their respective centers are symmetrical in opposite directions, the forces acting on all symmetrical parts in the reducer, except the circumferential force that produces the same-direction rotating torque, all cancel each other out and are automatically balanced, so the reducer has no time-varying rotational torsional vibration influence on the outside.

6. The self-balancing dual parallel compound nutating wheel reducer according to 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 each other in asymmetric manner. When the difference in the number of teeth of two parallel compound nutating wheel transmission components with the same structural parameters is an odd number, the two conical fixed gear rings on the partition plate and the conical fixed gear rings on the two end covers need to be installed and fixed by staggering half a tooth in the circumferential direction; when the difference in the number of teeth of the above two transmission components is an even number, there is no need to stagger the teeth in the circumferential direction; due to the electromechanically optimized reducer structure, there are four groups of gear teeth meshing for reduction at the same time, and the middle partition plate and the two conical fixed gear rings, the two compound nutating wheels and the low-speed moving ring and drum-shaped spline teeth of the bidirectional thrust ball bearing, and the rotor and the drum of the split motor are all integrated into one, so that the reducer has its own power source and has the characteristics of compact radial and axial structure, large load-bearing capacity, good rigidity, high transmission accuracy and transmission efficiency.

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