A power module

Abstract

This invention relates to a power module, comprising a motor, a torque sensor, and a harmonic reducer. The motor includes a housing, a stator assembly, and a rotor assembly. A brake stator is fixed to a partition at one end of the housing. The rotor assembly includes a hollow shaft, an annular groove, and an annular magnet. The annular groove is fitted onto the hollow shaft, and a brake rotor is fixed within the annular groove. The harmonic reducer includes a wave generator, a flexure, an output steel wheel, and a support bearing. The torque sensor is clamped and fixed between the outer ring of the support bearing and the other end of the housing, and is also fixed to the flexure. The wave generator is disposed within the flexure. One end of the hollow shaft passes through the torque sensor and the flexure, and is connected to the wave generator for transmission. The output steel wheel is fixed to the inner ring of the support bearing and is driven by the flexure with staggered teeth. The wiring harness of the torque sensor passes through the partition within the housing and is connected to the control circuit board. This invention is a power module with low inertia, high response, easy maintenance, and high integration.

Description

Technical Field

[0001] This invention belongs to the field of robot joint drive technology, and particularly relates to a power module. Background Technology

[0002] As robotic applications expand, collaborative robots, as automated labor that works in tandem with humans, are increasingly entering light industrial production. The movement of each degree of freedom in a collaborative robot is generated by the power modules at each joint.

[0003] In the fields of industrial automation, robot drive, and precision transmission, the power module, as a core drive unit, directly affects equipment performance due to its integration, structural compactness, and control precision. Traditional power modules are typically composed of separate components—motor, reducer, and sensors—and suffer from the following technical bottlenecks:

[0004] Loose structure and size limitations: The motor, brake, and reducer are arranged separately, resulting in redundant axial space and making it difficult to meet the requirements of lightweighting and miniaturization. Electromagnetic brakes are mostly placed externally at the end of the motor, increasing the module length, and the gap control between the brake rotor and stator is complicated, affecting braking response efficiency.

[0005] Low integration of torque detection: Torque sensors are mostly connected through external flanges, and the wiring harness needs to be routed around the outside. During the movement of the power module, the wiring harness is easily pulled, which not only affects the control accuracy, but also affects the movement range of the power module.

[0006] Encoder and sealing defects: Position detection often relies on a single magnetic encoder, which has weak anti-interference ability; the seal between the partition and the housing relies on traditional gaskets, which are prone to leakage in vibration environments, affecting the life of the circuit board.

[0007] The aforementioned defects have severely hampered the technological development of power modules and are technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0008] To address the aforementioned technical problems, the present invention aims to provide a power module with low inertia, high response, easy maintenance, and high integration.

[0009] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0010] A power module includes a motor, a torque sensor, and a harmonic reducer. The motor includes a housing, a stator assembly, and a rotor assembly. The stator assembly is fixed to the inner wall of the housing, and the rotor assembly is located inside the stator assembly.

[0011] A partition is fixed to one end of the housing, and a brake stator is fixed to the partition. The rotor assembly includes a hollow shaft, an annular groove, and an annular magnet. The annular magnet is fixed to the outer wall of the annular groove. The annular groove is sleeved on the hollow shaft. The annular groove and the partition are rotatably connected by a large-diameter bearing. A brake rotor is fixed inside the annular groove. When the motor is powered on, there is a gap between the brake stator and the brake rotor. When the motor is powered off, the brake stator and the brake rotor attract each other.

[0012] The harmonic reducer includes a wave generator, a flexible wheel, an output steel wheel, an inner ring of a support bearing, and an outer ring of a support bearing. The outer ring of the torque sensor is clamped and fixed between the outer ring of the support bearing and the other end of the housing. The inner ring of the torque sensor is fixed to the flexible wheel. The wave generator is disposed inside the flexible wheel and drives the flexible wheel to deform. One end of the hollow shaft passes through the torque sensor and the flexible wheel and is connected to the wave generator for transmission. The output steel wheel is fixed to the inner ring of the support bearing and is disposed outside the flexible wheel and is driven by the flexible wheel with staggered teeth.

[0013] A cover is also fastened to the partition, and a control circuit board is fixed in the space formed by the partition and the cover. The wiring harness of the torque sensor passes through the partition inside the housing and is connected to the control circuit board.

[0014] As a preferred embodiment, the annular groove and the hollow shaft are integrally formed, and both the annular groove and the hollow shaft are made of stainless steel. The outer wall of the annular groove is stepped, and the annular magnet is fixed to the outer wall of the annular groove, making it flush with the outer wall of the annular groove.

[0015] As a preferred embodiment, the middle part of the partition forms a countersunk hole facing the torque sensor, the inner wall of the annular groove is rotatably connected to the side wall of the countersunk hole through a large-diameter bearing, and the side wall of the countersunk hole is also provided with a retaining ring A to limit the inner ring of the large-diameter bearing.

[0016] As a preferred embodiment, the device also includes a T-shaped wire harness fitting, which includes an output disc and a hollow output shaft. The output disc is fixed to one end of the hollow output shaft and is in through communication with the hollow output shaft. The output disc is fixed to an output steel wheel. The hollow output shaft passes through the harmonic reducer and the hollow shaft body, and a gap is left between the hollow output shaft and the harmonic reducer and the hollow shaft body. The two ends of the hollow output shaft are respectively rotatably connected to the wave generator and the hollow shaft body through two support members.

[0017] As a preferred embodiment, a dual magnetic encoder sensing circuit assembly is also fixed inside the countersunk hole, and a magnetic ring A is fixed at the opening end of the annular groove near the hollow shaft. A magnetic ring seat is installed at the other end of the hollow output shaft, and a magnetic ring B is fixed on the magnetic ring seat. The magnetic ring A and the magnetic ring B are concentrically arranged and are correspondingly arranged on one side of the dual magnetic encoder sensing circuit assembly.

[0018] As a preferred embodiment, the end of the magnetic ring seat is also provided with a raised ridge, the middle of the buckle extends inward to form an inner protective tube, and the inner protective tube is in communication with the buckle. The end of the inner protective tube is also provided with a groove, the raised ridge is inserted into the groove, and the raised ridge and the groove are fitted with a gap.

[0019] As a preferred embodiment, the two end faces of the partition near the outer edge are respectively provided with a protruding ring and a protruding plate, the protruding ring and the protruding plate abutting against the inner wall of the cover and the shell respectively, and the partition, cover and shell are sealed by applying adhesive.

[0020] As a preferred embodiment, the wave generator includes an elliptical hub and a flexible bearing. The elliptical hub has a limiting flange on its outer side. The flexible bearing is sleeved on the outside of the elliptical hub and abuts against the limiting flange. The flexible bearing is embedded in the flexible wheel. The elliptical hub is sleeved on a hollow shaft and is driven by a spline.

[0021] As a preferred embodiment, the hollow shaft is further provided with a wedge-shaped limiting groove, and a wedge-shaped retaining spring is provided in the limiting groove to cooperate with it. The wedge-shaped retaining spring abuts against the end of the elliptical hub near the flexible wheel.

[0022] As a preferred embodiment, the signal processing circuit on the torque sensor is integrated on the control circuit board, and the signal processing circuit is connected to the strain gauge on the torque sensor via a wiring harness.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] The power module of this invention directly fixes the brake stator to the partition plate, and integrates the brake rotor into the annular groove. Large-diameter bearings are used to achieve coaxial support between the annular groove and the partition plate, eliminating the axial space occupied by traditional external brakes. The brake stator and rotor maintain a gap when the motor is energized, and close quickly through magnetic attraction when the power is off, achieving zero drag loss and millisecond-level braking response. Through the axially highly integrated design, this invention forms an axial series layout of "brake-motor-sensor-deceleration", reducing the overall length by more than 20%, which is especially suitable for space-constrained scenarios such as robot joints.

[0025] Meanwhile, the flexible wheel of the harmonic reducer and the torque sensor are clamped and fixed to the housing through the outer ring of the support bearing, forming an embedded torque sensing architecture, eliminating the intermediate transmission error of traditional flange-type sensors; the sensor does not rotate with the output shaft, avoiding wire harness tangling, and can realize multi-turn rotation at the output end, making the movement more flexible; in addition, the sensor wire harness is completely built-in, passing through the inner cavity of the housing and through the partition to the control circuit board, avoiding external electromagnetic interference and improving the signal-to-noise ratio of signal transmission. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute a limitation thereof.

[0027] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 and Figure 3 These are schematic diagrams of the cross-sectional structure of the present invention from different angles;

[0029] Figure 4 and Figure 5 These are schematic diagrams of the exploded structure of the present invention from different angles;

[0030] Figure 6 This is a cross-sectional structural diagram of the motor portion of the present invention;

[0031] Figure 7 and Figure 8 These are exploded structural diagrams of the motor of the present invention from different angles;

[0032] Figure 9 and Figure 10 These are exploded structural diagrams of the harmonic reducer and torque sensor of the present invention from different angles.

[0033] The attached figures are labeled as follows: 111, cover; 112, inner protective tube; 12, control circuit board; 13, partition plate; 130, countersunk hole; 131, dual magnetic encoder sensing circuit assembly; 132, convex ring; 133, convex plate; 14, snap ring A; 15, large diameter bearing; 20, housing; 21, stator assembly; 22, rotor assembly; 220, magnetic ring A; 221, hollow shaft; 222, annular groove; 23, annular magnet; 24, bearing shell; 30, brake. 31. Brake rotor; 41. Elliptical hub; 411. Limiting flange; 42. Flexible bearing; 43. Flexible wheel; 44. Output steel wheel; 45. Inner ring of support bearing; 46. Outer ring of support bearing; 47. Sealing ring; 48. Sealing ring A; 49. Sealing ring B; 50. Output disc; 51. Hollow output shaft; 511. Magnetic ring seat; 512. Magnetic ring B; 52. Support bearing; 6. Torque sensor; 61. Sealing ring C; 62. Positioning flange. Detailed Implementation

[0034] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0035] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0036] Furthermore, in the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more, unless explicitly defined otherwise.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0041] like Figures 1 to 5 As shown, a power module includes a motor, a torque sensor 6, and a harmonic reducer. The motor includes a housing 20, a stator assembly 21, and a rotor assembly 22. The stator assembly 21 is fixed to the inner wall of the housing 20, and the rotor assembly 22 is located inside the stator assembly 21. A partition 13 is fixed to one end of the housing 20, and a brake stator 30 is fixed on the partition 13. The rotor assembly 22 includes a hollow shaft 221, an annular groove 222, and an annular magnet 23. The annular magnet 23 is fixed to the outer wall of the annular groove 222, and the annular groove 222 is sleeved on the hollow shaft 221. The annular groove 222 and the partition 13 are rotatably connected by a large-diameter bearing 15. A brake rotor 31 is fixed inside the annular groove 222. When the motor is energized, a gap exists between the brake stator 30 and the brake rotor 31. When the motor is de-energized, the brake stator 30 and the brake rotor 31 attract each other. The specific principle is as follows: When the power module is energized, the brake stator generates magnetic force, which cancels out the magnetic force of the magnetic body on the brake stator, causing the rotor to spring open and rotate. When the power module is de-energized, the magnetic body of the brake stator generates magnetic force, causing the rotor to attract and achieve braking. A cover 111 is also fastened to the partition 13, and a control circuit board 12 is fixed within the accommodating space formed by the partition 13 and the cover 111.

[0042] like Figures 6 to 8 As shown, the annular groove 222 and the hollow shaft 221 are integrally formed, and both the annular groove 222 and the hollow shaft 221 are made of stainless steel. The use of stainless steel for the hollow shaft 221 and the annular groove 222 achieves the effect of magnetic shielding and prevents the motor magnetism from interfering with the brake magnetism. The outer wall of the annular groove 222 is stepped, and the annular magnet 23 is fixed to the outer wall of the annular groove 222.

[0043] The partition plate 13 has a countersunk hole 130 in the middle facing the torque sensor 6. The inner wall of the annular groove 222 is rotatably connected to the side wall of the countersunk hole via a large-diameter bearing 15. A retaining ring A14 is also provided on the side wall of the countersunk hole 130 to limit the inner ring of the large-diameter bearing 15. The large-diameter bearing can meet the installation space requirements of the brake, and at the same time, it can better support the rotor assembly, significantly improve the radial load capacity of the rotor, and suppress yaw vibration during high-speed operation.

[0044] The aforementioned motor stator adopts an integrated casting process, which allows the motor rotor to have a larger diameter and be directly glued to the motor shaft; the brake adopts a permanent magnet brake, which is smaller in size and increases in axial length; thus meeting the braking torque requirements.

[0045] The invention also includes a T-shaped wire harness fitting, which includes an output disc 50 and a hollow output shaft 51. The output disc 50 is fixed to one end of the hollow output shaft 51 and is in through communication with the hollow output shaft 51. The output disc 50 is fixed to the output steel wheel 44. The hollow output shaft 51 passes through the harmonic reducer and the hollow shaft 221, and there is a gap between it and the harmonic reducer and the hollow shaft 221. The two ends of the hollow output shaft 51 are rotatably connected to the wave generator and the hollow shaft 221 respectively through two support members.

[0046] The dual magnetic encoder sensing circuit assembly 131 is also fixed in the countersunk hole 130 of the partition plate 13. A magnetic ring A220 is also fixed at the open end of the annular groove 222 near the hollow shaft 221. A magnetic ring seat 511 is installed at the other end of the hollow output shaft 51. A magnetic ring B512 is fixed on the magnetic ring seat 511. The magnetic ring A220 and the magnetic ring B512 are concentrically arranged and are correspondingly arranged on one side of the dual magnetic encoder sensing circuit assembly 131.

[0047] The magnetic rings A220 and B512 of this invention monitor the rotational speed and position of the motor rotor and the hollow output shaft 51, respectively. Redundancy verification is achieved through the dual magnetic encoder sensing circuit assembly 131, improving anti-interference capability and detection accuracy. Furthermore, the dual magnetic encoder of this invention adopts a similar principle to an optical encoder, reading values ​​over the entire revolution to achieve an absolute positioning accuracy of 0.01°.

[0048] The aforementioned magnetic rings A and B are arranged concentrically, and the corresponding sensing devices on the dual magnetic encoder sensing circuit assembly are also arranged concentrically side by side, satisfying the requirement that the encoders are arranged separately at the output and input ends. This saves more than 5mm of axial space in the overall joint module and improves the encoder's reading and control accuracy.

[0049] The end of the magnetic ring seat 511 is also provided with a raised ridge. The middle part of the cover 111 extends inward to form an inner protective tube 112, and the inner protective tube 112 is in communication with the cover 111. The end of the inner protective tube 112 is also provided with a groove, and the raised ridge is inserted into the groove, and the raised ridge and the groove are fitted with a gap.

[0050] The through-through design of the hollow shaft 221, the hollow output shaft 51, and the inner protective tube allows cables or cooling media to be arranged through the shaft, meeting the stringent requirements of collaborative robot joints, medical robotic arms, and other applications for internal wiring.

[0051] The partition 13 is provided with a protruding ring 132 and a protruding plate 133 on its two ends near the outer edge. The protruding ring 132 and the protruding plate 133 abut against the inner wall of the cover 111 and the housing 20, respectively. The partition 13, the cover 111 and the housing 20 are sealed by applying adhesive.

[0052] The inner protective tube and the hollow output shaft 51 form a labyrinth-type sealing interface; the partition 13 forms a labyrinth-type sealing interface with the housing 20 and the cover 111 through the convex ring 132 and the convex plate 133. Combined with the adhesive coating process, it achieves an IP67 protection level and is suitable for high humidity and dusty industrial environments.

[0053] like Figure 9 and Figure 10 As shown, the harmonic reducer includes a wave generator, a flexible wheel 43, an output steel wheel 44, an inner ring 45 of a support bearing, and an outer ring 46 of a support bearing. The wiring harness of the torque sensor 6 passes through the partition 13 inside the housing 20 and is connected to the control circuit board 12. The outer ring of the torque sensor 6 is clamped and fixed between the outer ring 46 of the support bearing and the other end of the housing 20. The torque sensor 6 is also provided with a positioning protrusion 62, which abuts against the inner wall of the outer ring 46 of the support bearing. A sealing ring C61 is also provided between the torque sensor 6 and the outer ring 46 of the support bearing.

[0054] The inner ring of the torque sensor 6 is fixed to the flexible wheel 43. The wave generator is disposed inside the flexible wheel 43 and drives the flexible wheel 43 to deform. One end of the hollow shaft 221 passes through the torque sensor 6 and the flexible wheel 43 and is connected to the wave generator for transmission. The output steel wheel 44 is fixed to the inner ring 45 of the support bearing. The output steel wheel 44 is disposed outside the flexible wheel 43 and is driven by the flexible wheel 43 with staggered teeth.

[0055] The wave generator includes an elliptical hub 41 and a flexible bearing 42. The elliptical hub 41 has a limiting flange 411 on its outer side. The flexible bearing 42 is sleeved on the outside of the elliptical hub 41 and abuts against the limiting flange 411. The flexible bearing 42 is embedded within a flexible wheel 43. The elliptical hub 41 is sleeved on a hollow shaft 221 and driven by a spline. A bearing bush 24 is provided between one end of the hollow shaft 221 and the hollow output shaft 51. A support bearing 52 is also provided between the hollow output shaft 51 and the elliptical hub 41.

[0056] The wave generator of the harmonic reducer is connected to the shaft via a spline, which meets the requirements for disassembly and assembly and reduces the space occupied by bolts. The hollow shaft 221 is also provided with a wedge-shaped limiting groove, within which a wedge-shaped retaining spring is fitted. The wedge-shaped retaining spring abuts against the end of the elliptical hub 41 near the flexible wheel 43. The wedge-shaped retaining spring not only limits the installation of the wave generator but also allows for small axial displacement of the rotor during braking.

[0057] The signal processing circuit on the torque sensor 6 is integrated on the control circuit board 12, and the signal processing circuit is connected to the strain gauge on the torque sensor 6 via a wiring harness. This structure not only allows for an external amplifier for the torque sensor, reducing the rigid portion of the sensor and shortening the overall joint module, but also enables the strain gauge signal from the torque sensor to be directly connected to the signal processing circuit integrated on the control circuit board via a short path, reducing signal attenuation and delay, achieving microsecond-level dynamic torque feedback, and meeting the requirements of high-precision closed-loop control.

[0058] A sealing ring 47 is provided between the inner ring 45 and the outer ring 46 of the support bearing. A sealing ring A48 is provided between one side of the output steel wheel 44 and the inner ring 42 of the support bearing, and a sealing ring B49 is provided between the other side of the output steel wheel 44 and the output disc 50.

[0059] The outer ring of the support bearing of the present invention is also provided with the installation interface of the entire power module. The rolling bearing is used for fixing and output, which reduces the force on the housing end. The rolling bearing bears the load, reducing the assembly error and thus improving the absolute position accuracy of the entire arm. At the same time, the side cable exit method of the whole machine is more conducive to the installation of the entire arm.

[0060] This invention achieves a comprehensive breakthrough in the compactness, response speed, detection accuracy, and environmental adaptability of the power module through "high axial integration of functional modules", "deep fusion of sensing, driving and braking" and "rigid-sealed collaborative design". It is especially suitable for precision driving scenarios with extremely high requirements for space, weight, and real-time performance (such as bionic robot joints and aerospace actuators), and provides a standardized solution for the next generation of highly integrated electromechanical systems.

[0061] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0062] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A power module comprising a motor, a torque sensor (6), and a harmonic reducer, wherein the motor comprises a housing (20), a stator assembly (21), and a rotor assembly (22), the stator assembly (21) being fixed to the inner wall of the housing (20), and the rotor assembly (22) being located inside the stator assembly (21), characterized in that: One end of the housing (20) is fixed with a partition (13), and a brake stator (30) is fixed on the partition (13). The rotor assembly (22) includes a hollow shaft (221), an annular groove (222) and an annular magnet (23). The annular magnet (23) is fixed on the outer wall of the annular groove (222). The annular groove (222) is sleeved on the hollow shaft (221). The annular groove (222) and the partition (13) are rotatably connected by a large-diameter bearing (15). A brake rotor (31) is fixed inside the annular groove (222). When the motor is powered on, there is a gap between the brake stator (30) and the brake rotor (31). When the motor is powered off, the brake stator (30) and the brake rotor (31) attract each other. The harmonic reducer includes a wave generator, a flexible wheel (43), an output steel wheel (44), an inner ring (45) of a support bearing, and an outer ring (46) of a support bearing. The outer ring of the torque sensor (6) is clamped and fixed between the outer ring (46) of the support bearing and the other end of the housing (20). The inner ring of the torque sensor (6) is fixed to the flexible wheel (43). The wave generator is set inside the flexible wheel (43) and drives the flexible wheel (43) to deform. One end of the hollow shaft (221) passes through the torque sensor (6) and the flexible wheel (43) and is connected to the wave generator for transmission. The output steel wheel (44) is fixed to the inner ring (45) of the support bearing. The output steel wheel (44) is set outside the flexible wheel (43) and is driven by the flexible wheel (43) with staggered teeth. A cover (111) is also fastened and fixed on the partition (13). A control circuit board (12) is fixed in the accommodating space formed by the partition (13) and the cover (111). The wiring harness of the torque sensor (6) passes through the partition (13) in the housing (20) and is connected to the control circuit board (12). The partition (13) has a countersunk hole (130) in the middle facing the torque sensor (6). It also includes a T-shaped wire harness fitting, which includes an output disc (50) and a hollow output shaft (51). The output disc (50) is fixed to one end of the hollow output shaft (51) and is in through communication with the hollow output shaft (51). The output disc (50) is fixed to the output steel wheel (44). The hollow output shaft (51) passes through the harmonic reducer and the hollow shaft body (221) and leaves a gap between it and the harmonic reducer and the hollow shaft body (221). The two ends of the hollow output shaft (51) are respectively rotatably connected to the wave generator and the hollow shaft body (221) through two support members. The countersunk hole (130) is also fixed with a dual magnetic encoder sensing circuit assembly (131). A magnetic ring A (220) is also fixed at the opening end of the annular groove (222) near the hollow shaft (221). A magnetic ring seat (511) is installed at the other end of the hollow output shaft (51). A magnetic ring B (512) is fixed on the magnetic ring seat (511). The magnetic ring A (220) and the magnetic ring B (512) are concentrically arranged and are correspondingly arranged on one side of the dual magnetic encoder sensing circuit assembly (131). The wave generator includes an elliptical hub (41) and a flexible bearing (42). The elliptical hub (41) has a limiting flange (411) on its outer side. The flexible bearing (42) is sleeved on the outside of the elliptical hub (41) and abuts against the limiting flange (411). The flexible bearing (42) is embedded in the flexible wheel (43). The elliptical hub (41) is sleeved on the hollow shaft (221) and driven by a spline.

2. A power module according to claim 1, characterized in that, The annular groove (222) and the hollow shaft (221) are integrally formed, and both the annular groove (222) and the hollow shaft (221) are made of stainless steel. The outer wall of the annular groove (222) is stepped, and the annular magnet (23) is fixed to the outer wall of the annular groove (222).

3. A power module according to claim 1, characterized in that, The inner wall of the annular groove (222) is rotatably connected to the side wall of the countersunk hole (130) through a large-diameter bearing (15), and a retaining ring A (14) is provided on the side wall of the countersunk hole (130) to limit the inner ring of the large-diameter bearing (15).

4. A power module according to claim 1, characterized in that, The end of the magnetic ring seat (511) is also provided with a ring of protruding ribs. The middle part of the buckle (111) extends inward to form an inner protective tube (112), and the inner protective tube (112) is connected to the buckle (111). The end of the inner protective tube (112) is also provided with a groove, and the protruding rib is inserted into the groove, and the protruding rib and the groove are fitted with a gap.

5. A power module according to claim 1, characterized in that, The partition (13) has a protruding ring (132) and a protruding plate (133) on its two ends near the outer edge. The protruding ring (132) and the protruding plate (133) abut against the inner wall of the cover (111) and the shell (20) respectively. The partition (13), the cover (111) and the shell (20) are sealed by applying glue.

6. A power module according to claim 1, characterized in that, The hollow shaft (221) is also provided with a wedge-shaped limiting groove, and a wedge-shaped retaining spring is provided in the limiting groove to cooperate with it. The wedge-shaped retaining spring abuts against the end of the elliptical hub (41) near the flexible wheel (43).

7. A power module according to claim 1, characterized in that, The signal processing circuit on the torque sensor (6) is integrated on the control circuit board (12), and the signal processing circuit is connected to the strain gauge on the torque sensor (6) via a wiring harness.

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