A dual-rotor joint motor

Abstract

The present invention relates to a dual-rotor joint motor, belonging to the technical field of motors, and comprising: a base assembly including a main shaft, a main shaft end seat, and a fixed tooth seat, with a coding circuit board at one end and a drive circuit board provided in the middle; an output assembly in which the output tooth seat is connected to an output end cover with a magnetic ring, and the main shaft end seat is within the output tooth seat; an intermediate shaft assembly including an intermediate tooth seat and an inner intermediate tooth portion; and a pair of core motor assemblies sleeved on the main shaft, each core motor assembly including a rotor having a receiving groove and a plug shaft, a stator sleeved on the plug shaft, and a flexspline having an annular groove on the outer periphery of the stator, the teeth of the flexspline meshing with the teeth of the fixed tooth seat, the intermediate tooth seat, and the output tooth seat, and rollers cooperating with the annular groove of the flexspline being provided on the outer periphery of the stator. The joint motor of the present invention adopts a dual-rotor and harmonic reducer structure, and the dual rotors run in opposite directions at the same speed, canceling the inertial torque and reducing the influence of the rotor movement on the output movement.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and particularly to a dual-rotor joint motor. Background Art

[0002] In order to meet the urgent social demand for productivity, robotic technologies such as robotic arms and humanoid robots are widely used in various fields to fill the productivity gap in the population. As a core component of such robots, the performance of the joint motor directly determines the productivity level of the robot.

[0003] Most of the existing joint motors adopt a single-rotor and high-speed ratio reducer structure. Due to the large speed ratio, the rotor of the joint motor is usually required to operate at high frequency and high speed, and at the same time, the moment of inertia of the electronic rotor is relatively large. These two characteristics make the joint motor greatly affected by the inertial torque during operation, resulting in large vibrations, thereby significantly reducing the working efficiency, positioning accuracy and stability of the joint motor. Summary of the Invention

[0004] In order to solve the influence of the inertial torque of the single-rotor joint motor on the output motion of the joint motor, the present invention proposes a dual-rotor joint motor, which adopts a dual-rotor structure and a harmonic reducer structure, and offsets the inertial torques of the two rotors by the reverse and equal-speed operation of the dual rotors, thereby reducing the influence of the rotor motion on the output motion of the joint motor.

[0005] The object of the present invention can be achieved by the following technical solutions:

[0006] A dual-rotor joint motor, comprising:

[0007] A base assembly, the base assembly includes a main shaft, a main shaft end seat provided at one end of the main shaft, and a fixed tooth seat provided at the other end of the main shaft. A coding circuit board is provided on a side of the main shaft end seat facing away from the main shaft, and a drive circuit board is provided between the main shaft and the fixed tooth seat;

[0008] An output assembly, the output assembly includes an output tooth seat and an output end cover connected to each other. A magnetic ring is provided on the output end cover, and the main shaft end seat is located inside the output tooth seat;

[0009] An intermediate shaft assembly, the intermediate shaft assembly includes an intermediate tooth seat, and an intermediate tooth portion is provided in the middle of the inner side of the intermediate tooth seat. The fixed tooth seat and the output tooth seat extend into the intermediate tooth seat from both sides of the intermediate tooth seat respectively;

[0010] A pair of core motor assemblies sleeved on the main shaft, the core motor assemblies include:

[0011] A rotor, the rotor has a receiving groove, and a plug shaft is provided in the middle of the receiving groove. The plug shaft is sleeved on the main shaft;

[0012] A stator, the stator being sleeved on the plug shaft;

[0013] A flexspline, the flexspline being located outside the stator, and an annular groove being provided on one side of the flexspline close to the stator; a flexspline tooth part is provided on the periphery of the flexspline, and the teeth on the flexspline tooth part are respectively meshed and connected with a fixed tooth part arranged on the inner side of the fixed tooth seat, the intermediate tooth part, and an output tooth part arranged in the output tooth seat;

[0014] A plurality of rollers, the plurality of rollers being arranged at intervals outside the stator and rotatably connected with the stator, and the outer sides of the rollers being located in the annular groove of the flexspline. Specifically, a rotating shaft is provided at the connection between the roller and the periphery of the stator, the roller can rotate around the rotating shaft, the roller can also roll in the annular groove in the inner ring of the flexspline, and the movement of the flexspline in the axial direction can be restricted.

[0015] Further, the coding circuit board is fixed on the main shaft end seat by bolts, the main shaft end seat is fixed on the main shaft by bolts, and the fixed tooth seat is fixed on the main shaft by bolts.

[0016] Further, the output tooth seat and the output end cover are connected by bolts, and the magnetic ring is fixed on the output end cover by an adhesive method.

[0017] Further, the stator is fixed on the main shaft end seat by bolts.

[0018] Further, a second bearing is provided on the periphery of the main shaft end seat, and the output tooth seat is rotatably connected through the second bearing.

[0019] Further, threaded holes are uniformly arranged along the circumferential direction of the intermediate tooth seat. When necessary, the intermediate tooth seat can also be used as a rotating element to be connected with other external parts. That is, one end of the dual-rotor joint motor provided by the present invention is fixed on a base, and there are two motion output ends at the same time.

[0020] Further, there is a small tooth number difference between the teeth of the fixed tooth part and the teeth of the intermediate tooth part.

[0021] Further, there is a small tooth number difference between the teeth of the intermediate tooth part and the teeth of the output tooth part.

[0022] Further, the magnetic ring and the coding circuit board are arranged oppositely and coaxial.

[0023] Further, the output tooth seat and the output end cover are fixedly connected, a secondary shaft is provided in the middle of the output end cover, and the magnetic ring is sleeved on the secondary shaft.

[0024] Further, first bearings are respectively arranged at the joints of the intermediate gear seat with the fixed gear seat and the output gear seat.

[0025] Further, the first bearing is connected to the intermediate gear seat by means of interference fit.

[0026] Further, the stator of the core motor assembly near the spindle end seat is fixedly connected to the spindle end seat.

[0027] Further, a gasket is sleeved on the spindle rod body between the pair of core motor assemblies, and the stators of the pair of core motor assemblies are connected to the drive circuit board through the three-phase leads led out.

[0028] Compared with the prior art, the joint motor provided by the present invention adopts a dual-rotor structure and a harmonic reducer structure, and the inertial torques of the two rotors are offset by the reverse and constant-speed operation of the dual rotors, thereby reducing the influence of the rotor movement on the output movement of the joint motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is an exploded view of the dual-rotor joint motor in the embodiment;

[0030] Figure 2 is a perspective view of the dual-rotor joint motor in the embodiment;

[0031] Figure 3 is an exploded view of the output assembly in the embodiment;

[0032] Figure 4 is a perspective view of the output assembly in the embodiment;

[0033] Figure 5 is an exploded view of the intermediate shaft assembly in the embodiment;

[0034] Figure 6 is an exploded view of the core motor assembly in the embodiment;

[0035] Figure 7 is a perspective view of the core motor assembly in the embodiment;

[0036] Figure 8 is an exploded view of the base assembly in the embodiment;

[0037] Figure 9 is a perspective view of the base assembly in the embodiment;

[0038] Figure 10 is a sectional view of the dual-rotor joint motor in the embodiment;

[0039] Figure 11 is a structural schematic diagram of the dual-rotor joint motor in the embodiment;

[0040] As shown in the figure by the reference numerals: 1 - output component; 11 - output tooth seat; 12 - magnetic ring; 13 - output end cover; 14 - output tooth portion; 15 - auxiliary shaft; 2 - intermediate shaft assembly; 21 - first bearing; 22 - intermediate tooth seat; 23 - threaded hole; 24 - intermediate tooth portion; 3 - core motor assembly; 31 - stator; 32 - rotor; 33 - roller; 34 - flexspline; 35 - plug shaft; 36 - flexspline tooth portion; 4 - base assembly; 41 - coding circuit board; 42 - main shaft end seat; 43 - main shaft; 44 - drive circuit board; 45 - fixed tooth seat; 46 - fixed tooth portion; 5 - gasket; 6 - second bearing. Specific embodiments

[0041] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0042] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0043] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0044] In addition, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but may be slightly inclined.

[0045] Embodiment

[0046] In order to solve the influence of the inertial torque of the single-rotor joint motor on the output motion of the joint motor, this embodiment provides a double-rotor joint motor, and the specific structure is shown in Figures 1-11 , including:

[0047] Base component 4, the base component 4 includes a main shaft 43, a main shaft end seat 42 provided at one end of the main shaft 43, and a fixed tooth seat 45 provided at the other end of the main shaft 43. A coding circuit board 41 is provided on the side of the main shaft end seat 42 facing away from the main shaft 43, and a drive circuit board 44 is provided between the main shaft 43 and the fixed tooth seat 45;

[0048] Output component 1, the output component 1 includes a connected output tooth seat 11 and an output end cover 13. A magnetic ring 12 is provided on the output end cover 13, and the main shaft end seat 42 is located within the output tooth seat 11;

[0049] Intermediate shaft component 2, the intermediate shaft component 2 includes an intermediate tooth seat 22. An intermediate tooth portion 24 is provided in the middle of the inner side of the intermediate tooth seat 22, and the fixed tooth seat 45 and the output tooth seat 11 extend into the intermediate tooth seat 22 from both sides respectively;

[0050] A pair of core motor components 3 sleeved on the main shaft 43, the core motor components 3 include:

[0051] A rotor 32, the rotor 32 has a receiving groove, and a plug shaft 35 is provided in the middle of the receiving groove. The plug shaft 35 is sleeved on the main shaft 43;

[0052] A stator 31, the stator 31 is sleeved on the plug shaft 35;

[0053] A flexspline 34, the flexspline 34 is located outside the stator 31. An annular groove is provided on the side of the flexspline 34 close to the stator 31; Flexspline teeth 36 are provided on the outside of the flexspline 34, and the teeth on the flexspline teeth 36 are respectively meshed and connected with a fixed tooth portion 46 provided on the inner side of the fixed tooth seat 45, the intermediate tooth portion 24, and an output tooth portion 14 provided in the output tooth seat 11;

[0054] A plurality of rollers 33, the plurality of rollers 33 are spaced apart and provided on the outside of the stator 31 and are rotatably connected to the stator 31. The outside of the rollers 33 is located in the annular groove of the flexspline 34. Specifically, a rotating shaft is provided at the connection between the rollers 33 and the outside of the stator 31, and the rollers 33 can rotate around the rotating shaft. The rollers 33 can also roll in the annular groove in the inner ring of the flexspline 34, and can limit the movement of the flexspline 34 in the axial direction.

[0055] Please refer to Figures 8-9 again. In this embodiment, the coding circuit board 41 is fixed on the main shaft end seat 42 by bolts, the main shaft end seat 42 is fixed on the main shaft 43 by bolts, and the fixed tooth seat 45 is fixed on the main shaft 43 by bolts. Among them, the coding circuit board 41 calculates the movement angle of the output component 1 by identifying the magnetic field direction of the magnetic ring 12.

[0056] Please refer to again Figures 3-4 In this embodiment, the output tooth seat 11 and the output end cover 13 are connected by bolts, and the magnetic ring 12 is fixed on the output end cover 13 by bonding.

[0057] In this embodiment, the stator 31 is fixed on the main shaft end seat 42 by bolts.

[0058] In this embodiment, a second bearing 6 is arranged on the periphery of the main shaft end seat 42, and the output tooth seat 11 is rotatably connected through the second bearing 6.

[0059] In this embodiment, there is a small tooth number difference between the teeth of the fixed tooth part 46 and the teeth of the intermediate tooth part 24; there is a small tooth number difference between the teeth of the intermediate tooth part 24 and the teeth of the output tooth part 14. Preferably, the tooth difference is recommended to be 2 teeth or 4 teeth. The smaller the tooth difference, the larger the reduction ratio.

[0060] In this embodiment, the magnetic ring 12 and the coding circuit board 41 are arranged opposite to each other and coaxial.

[0061] In this embodiment, the output tooth seat 11 and the output end cover 13 are fixedly connected. A secondary shaft 15 is arranged in the middle of the output end cover 13, and the magnetic ring 12 is sleeved on the secondary shaft 15.

[0062] In this embodiment, first bearings 21 are respectively arranged at the joints of the intermediate tooth seat 22 with the fixed tooth seat 45 and the output tooth seat 11. The first bearings 21 are preferably connected to the intermediate tooth seat 22 by interference fit.

[0063] In this embodiment, threaded holes 23 are uniformly arranged along the circumferential direction of the intermediate tooth seat 22. When necessary, the intermediate tooth seat 22 can also be used as a rotating element to connect with other external parts. It is equivalent to that one end of the dual-rotor joint motor provided in this embodiment is fixed on the base, and there are two motion output ends at the same time.

[0064] In this embodiment, the stator 31 of the core motor assembly 3 near the main shaft end seat 42 is fixedly connected to the main shaft end seat 42.

[0065] In this embodiment, a gasket 5 is sleeved on the rod body of the main shaft 43 between the pair of core motor assemblies 3, and the stators 31 of the pair of core motor assemblies 3 are connected to the drive circuit board 44 through the led-out three-phase leads.

[0066] Operating principle:

[0067] The external device sends operation instructions containing parameters such as rotation angle, speed, and torque to the drive circuit board 44 and provides power for it. After receiving the instructions, the drive circuit board 44 analyzes them through the internal drive control algorithm, and then drives the two rotors 32 to perform constant-speed reverse movement. In this process, the rollers 33 on the rotor 32 will press against the teeth on the flexspline 34, so that the teeth on the flexspline 34 mesh with the teeth on the fixed tooth seat 45, the intermediate tooth seat 22, and the output tooth seat 11 respectively. It should be noted that the teeth between the fixed tooth seat 45 and the intermediate tooth seat 22, and the teeth between the intermediate tooth seat 22 and the output tooth seat 11 all have the characteristic of a small difference in the number of teeth. Based on this characteristic, a large reduction ratio reducer is formed. This reducer can convert the high-speed and small-torque movement of the rotor 32 into the low-speed and large-torque movement of the output component 1. In addition, since the two rotors 32 are in a reverse constant-speed movement state, the inertial torques generated by them on the main shaft 43 can cancel each other out, effectively improving the stability of the equipment operation. Among them, the drive control algorithm mentioned in the operation principle is a common algorithm well-known to those skilled in the art and is not the focus protected by the present invention, so it will not be elaborated again here.

[0068] The calculation method of the reduction ratio of the joint motor is as follows: The number of teeth of the fixed tooth seat 45 as the internal gear ring is denoted as Z0, the number of teeth of the flexspline 34 as the external gear ring is denoted as Z1, the number of teeth of the intermediate tooth seat 22 as the internal gear ring is denoted as Z2, and the number of teeth of the output tooth seat 11 as the internal gear ring is denoted as Z3.

[0069] For the gear train composed of the fixed tooth seat 45, the flexspline 34 and the intermediate tooth seat 22, the fixed tooth seat 45 is the fixed part, the rotor 32 is the motion input part, the intermediate tooth seat 22 is the motion output part, and the reduction ratio n 22 / n m0 =(Z2 - Z0) / Z2.

[0070] For the gear train composed of the intermediate tooth seat 22, the flexspline 34 and the output tooth seat 11, the intermediate tooth seat 22 and the rotor 32 are the motion input parts, the output tooth seat 11 is the motion output part, and the reduction ratio is

[0071] n 11 =(Z3 - Z2)×n m1 / Z3 + z2×n 22 / Z3, then n 11 =(Z3 - Z2)×n m1 / Z3 + (Z2 - Z0)×n m0 / Z3.

[0072] Among them, the module and pressure angle of the Z0 tooth and the Z1 tooth are equal, while the module and pressure angle of the Z2 tooth are not equal to those of the Z1 tooth, but the normal pitch of Z2 is the same as that of Z1.

[0073] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the relevant art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A dual-rotor joint motor, characterized in that: include: A base assembly (4), the base assembly (4) comprising a main shaft (43), a main shaft end seat (42) arranged at one end of the main shaft (43), and a fixed gear seat (45) arranged at the other end of the main shaft (43), an encoding circuit board (41) being arranged on a side of the main shaft end seat (42) facing away from the main shaft (43), and a driving circuit board (44) being arranged between the main shaft (43) and the fixed gear seat (45); An output assembly (1), the output assembly (1) comprising an output gear seat (11) and an output end cover (13) connected to each other, the output end cover (13) being provided with a magnetic ring (12), and the main shaft end seat (42) being located inside the output gear seat (11); An intermediate shaft assembly (2), the intermediate shaft assembly (2) comprising an intermediate tooth seat (22), an intermediate tooth portion (24) being provided at the middle of the inner side of the intermediate tooth seat (22), the fixed tooth seat (45) and the output tooth seat (11) respectively extending into the intermediate tooth seat (22) from both sides; A pair of core motor components (3) sleeved on the main shaft (43), the core motor components (3) comprising: A rotor (32), the rotor (32) having a receiving groove, a plug-in shaft (35) being arranged in the middle of the receiving groove, and the plug-in shaft (35) being sleeved on the main shaft (43); A stator (31), the stator (31) being sleeved on the plug-in shaft (35); a flexible wheel (34), the flexible wheel (34) being disposed on the periphery of the stator (31), and an annular groove being provided on a side of the flexible wheel (34) close to the stator (31); a flexible wheel tooth portion (36) being provided on the periphery of the flexible wheel (34), and teeth on the flexible wheel tooth portion (36) being meshedly connected with a fixed tooth portion (46) provided on the inner side of the fixed tooth seat (45), the intermediate tooth portion (24), and an output tooth portion (14) provided in the output tooth seat (11); A plurality of rollers (33) are arranged at intervals on the periphery of the stator (31) and are rotatably connected to the stator (31), and the outer sides of the rollers (33) are located in the annular grooves of the flexible wheel (34).

2. A dual-rotor joint motor according to claim 1, characterized in that: A second bearing (6) is disposed on the periphery of the main shaft end seat (42), and is rotatably connected to the output gear seat (11) via the second bearing (6).

3. A dual-rotor joint motor according to claim 1, characterized in that: The teeth of the fixed tooth portion (46) and the teeth of the intermediate tooth portion (24) have a small difference in the number of teeth.

4. A dual-rotor joint motor according to claim 1, characterized in that: The teeth of the intermediate tooth portion (24) and the teeth of the output tooth portion (14) differ slightly in number of teeth.

5. The dual-rotor joint motor according to claim 1, characterized in that: The magnetic ring (12) and the encoding circuit board (41) are arranged opposite to each other and are coaxial.

6. A dual-rotor joint motor according to claim 1, characterized in that: The output gear seat (11) and the output end cover (13) are fixedly connected, a secondary shaft (15) is provided in the middle of the output end cover (13), and the magnetic ring (12) is sleeved on the secondary shaft (15).

7. A dual-rotor joint motor according to claim 6, characterized in that: First bearings (21) are respectively provided at the connection points between the intermediate gear seat (22), the fixed gear seat (45) and the output gear seat (11).

8. A dual-rotor joint motor according to claim 7, characterized in that: The first bearing (21) is connected to the intermediate gear seat (22) by means of a transition fit.

9. The dual-rotor joint motor according to claim 1, characterized in that: The stator (31) of the core motor assembly (3) near the spindle end seat (42) is fixedly connected to the spindle end seat (42).

10. The dual-rotor joint motor according to claim 1, characterized in that: A gasket (5) is sleeved on the shaft of the main shaft (43) between the pair of core motor components (3), and the stators (31) of the pair of core motor components (3) are connected to the driving circuit board (44) via three-phase lead wires.

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