Hollow integrated planetary joint motor and robot

Abstract

The invention discloses a hollow integrated planetary joint motor and a robot. The hollow integrated planetary joint motor comprises a shell; the planetary transmission mechanism is arranged in the shell, the planetary transmission mechanism comprises a gear ring, a sun gear and a plurality of planetary gears, and a through hole is formed in the center of the sun gear; the driving mechanism is arranged in the shell and is in transmission connection with the sun gear; the hollow shaft penetrates through the shell, the planetary transmission mechanism and the driving mechanism in the axis direction of the shell to form a wire harness channel, an output flange is coaxially and fixedly arranged at one end of the hollow shaft, and the output flange is in transmission connection with the multiple planetary wheels; and the branching assembly is arranged in the hollow shaft so as to separately arrange the wire harnesses in the hollow shaft. Through the hollow shaft penetrating through the shell and the built-in branching assembly, wire harnesses of the whole machine are simplified, winding and abrasion of the wire harnesses are avoided, and the running safety of the robot is improved.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to a hollow integrated planetary joint motor and robot. Background Technology

[0002] Humanoid robot technology, as an important branch of robotics, has received widespread attention and development in recent years. These robots aim to mimic human appearance and motor abilities and are applied in various scenarios such as service, entertainment, healthcare, and education. Joint motors are key actuators in humanoid robots, driving the movement of each joint; their performance directly affects the robot's flexibility, load capacity, accuracy, and reliability. With advancements in artificial intelligence, sensor technology, and materials science, humanoid robots are developing towards greater intelligence, lighter weight, and higher efficiency, placing higher demands on joint motors, such as high torque output, compact structure, low energy consumption, high response speed, and good shock resistance. In industrial robots and advanced service robots, the design of joint motors often needs to balance power density, cost, and maintainability to meet the needs of large-scale commercial applications.

[0003] Currently, the wiring harness of humanoid robots needs to be connected to the joint motors, power supply, and main control board through multiple sets of lines. This not only increases the complexity of the wiring harness layout, but also makes the wiring harness prone to tangling, friction and wear during robot movement, affecting operational safety. Summary of the Invention

[0004] To address the problem that existing humanoid robots require multiple sets of wires to connect each joint motor to the power supply and main control board, resulting in complex wiring harness layout and easy tangling and friction wear during robot movement, this invention simplifies the overall wiring harness by using a hollow shaft that penetrates the shell and an internal wiring assembly. This avoids tangling and wear, and improves the robot's operational safety.

[0005] Based on this, in a first aspect of the present invention, a hollow integrated planetary joint motor is provided, comprising:

[0006] case;

[0007] A planetary transmission mechanism is disposed within the housing. The planetary transmission mechanism includes a ring gear, a sun gear, and multiple planet gears. A through hole is provided at the center of the sun gear.

[0008] A drive mechanism is disposed within the housing and is connected to the sun gear via a transmission.

[0009] A hollow shaft passes through the housing, the planetary transmission mechanism, and the drive mechanism along the axial direction of the housing to form a wire harness channel. One end of the hollow shaft is coaxially fixed with an output flange, which is connected to multiple planetary gears.

[0010] A wire splitter assembly is disposed within the hollow shaft to separate and arrange the wire harness within the hollow shaft.

[0011] Preferably, the housing includes a front cover, a middle cover, and a rear cover;

[0012] The front cover, middle cover and rear cover are detachably connected along the axial direction of the housing. The front cover has a first wiring hole at its center, the middle cover has a second wiring hole at its center, and the rear cover has a third wiring hole at its center. The first wiring hole, the second wiring hole and the third wiring hole are coaxially arranged with the hollow shaft.

[0013] The front cover has an annular first limiting part protruding into the housing, and the toothed ring is embedded in the first limiting part and fixedly connected to the front cover;

[0014] The inner wall of the middle cover is integrally formed with an annular partition, which divides the interior of the housing into a first mounting cavity and a second mounting cavity.

[0015] Preferably, the tooth profiles of the gear ring, the sun gear, and the planet gears are all involute tooth profiles.

[0016] Preferably, the driving mechanism is a frameless motor disposed in the first mounting cavity;

[0017] The front cover has an annular second limiting part protruding on the side facing the frameless motor, and the frameless motor is embedded in the second limiting part and is detachably and fixedly connected to the front cover.

[0018] The output end of the frameless motor is connected to the sun gear drive.

[0019] Preferably, the joint motor further includes a detection mechanism disposed within the second mounting cavity;

[0020] The detection mechanism is a hollow angle encoder, which includes a stator and two rotors. One rotor is connected to the output end of the frameless motor to collect the motion parameters of the output end of the frameless motor, and the other rotor is connected to the hollow shaft to collect the motion parameters of the output flange.

[0021] Preferably, the joint motor further includes a controller disposed within the second mounting cavity;

[0022] The controller is a PCB assembly with a central opening. The controller is electrically connected to the drive mechanism and the detection mechanism, and controls the operation of the drive mechanism.

[0023] Preferably, the controller is provided with a connection component, which includes a plurality of connectors for connecting power lines and signal lines to receive power and signals and to connect the plurality of joint motors in series.

[0024] The rear cover has a clearance hole corresponding to the position of the connector.

[0025] Preferably, the branching assembly includes:

[0026] A cylindrical body is inserted into the hollow shaft and spaced apart from the hollow shaft, with one end of the cylindrical body fixedly connected to the rear cover;

[0027] A separator is disposed inside the cylinder and divides the cylinder into a high-voltage cavity and a low-voltage cavity to separate and arrange the power lines and signal lines.

[0028] A bearing is disposed at one end of the cylinder away from the rear cover. The outer ring and inner ring of the bearing are coaxially and fixedly connected to the hollow shaft and the cylinder, respectively, to support the cylinder.

[0029] Preferably, a metal shielding mesh is provided inside the weak current cavity, and the metal shielding mesh extends along the axial direction of the separator.

[0030] In a second aspect of the invention, a humanoid robot is also proposed, comprising a robot body and the aforementioned hollow integrated planetary joint motor.

[0031] The joint motors are connected to the joints of the robot body, and several joint motors are connected in series.

[0032] Compared with the above-mentioned background technology, the technical solution provided by the present invention has at least the following technical effects:

[0033] This invention utilizes a hollow shaft that runs along the axis of the shell, penetrating the planetary transmission mechanism and the drive mechanism to form a continuous wiring harness channel. Combined with the wiring distribution components within the hollow shaft, this achieves the containment and separate arrangement of the entire wiring harness. Compared to existing technologies where multiple sets of wires connect to each joint motor separately, this invention simplifies the overall wiring harness layout of the humanoid robot and reduces the amount of wiring harness used. Simultaneously, the wiring harness is arranged within a closed hollow channel, avoiding friction and wear between the wiring harness and other components during robot movement, as well as the wiring harness entanglement problem caused by joint rotation, thus improving the safety of robot operation. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0035] Figure 1 This is an exploded view of the joint motor provided in an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the wiring harness arrangement of the robot provided in an embodiment of the present invention.

[0037] Figure Labels

[0038] 11. Front cover; 12. Middle cover; 13. Rear cover; 2. Planetary transmission mechanism; 3. Frameless motor; 4. Hollow shaft; 5. Hollow angle encoder; 6. Controller; 61. Connector; 71. Input signal line; 72. Input power line; 73. Output power line; 74. Output signal line. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] As described in the background section, currently, the wiring harness of a humanoid robot needs to be connected to the joint motors, power supply, and main control board through multiple sets of lines. This not only increases the complexity of the wiring harness layout but also makes the wiring harness prone to tangling, friction, and wear during robot movement, affecting operational safety.

[0042] Based on this, in a first aspect of the present invention, a hollow integrated planetary joint motor is provided, referring to... Figure 1 and Figure 2The system comprises a housing, a planetary transmission mechanism 2, a drive mechanism, a hollow shaft 4, a detection mechanism, a controller 6, and a wiring assembly. The housing provides mounting support and protection for each component, while its internal chambers allow for the orderly arrangement of these components. The planetary transmission mechanism 2, located within the housing, reduces and transmits the power output from the drive mechanism to meet the torque output requirements of the joint motor. The drive mechanism, located within the housing and connected to the planetary transmission mechanism 2, provides the power required for the joint motor's operation. The hollow shaft 4 runs along the axial direction of the housing, penetrating the housing, the planetary transmission mechanism 2, and the drive mechanism, forming a continuous wiring harness channel for the entire system's wiring harness. The wiring assembly, located within the hollow shaft 4, separates the power and signal lines within the hollow shaft 4 to prevent tangled wiring and mutual interference. The detection mechanism collects motion parameters from the drive mechanism and the hollow shaft 4, providing data support for the joint motor's control and enabling position memory after power failure. The controller 6 receives parameters collected by the detection mechanism and controls the drive mechanism's operating status, while also serving as a relay for power and signal transmission.

[0043] Specifically, the housing includes a front cover 11, a middle cover 12, and a rear cover 13. The entire housing is made of lightweight, high-strength materials, including but not limited to lightweight aluminum alloy, to reduce the overall weight of the joint motors, meeting the lightweight requirements of humanoid robots while ensuring structural rigidity to withstand external impacts. Furthermore, the front cover 11, middle cover 12, and rear cover 13 are assembled along the axial direction of the housing using a detachable connection method, including but not limited to bolt connections and snap-fit ​​connections. Even further, sealing elements are provided between the connecting surfaces of the front cover 11 and the middle cover 12, and between the middle cover 12 and the rear cover 13. These sealing elements include, but are not limited to, sealing rings. The sealing rings are made of wear-resistant and aging-resistant elastic materials, such as nitrile rubber and fluororubber. The sealing elements are embedded in the sealing grooves of the connecting surfaces to prevent dust, moisture, and other impurities from entering the housing cavity, avoiding contamination or corrosion of internal gears, circuits, and other components, thereby ensuring the operational reliability of the joint motors.

[0044] As an optional implementation, when the front cover 11, the middle cover 12 and the rear cover 13 are connected by bolts, corresponding bolt holes are evenly distributed along the circumference of the front cover 11, the middle cover 12 and the rear cover 13. The specific number of bolt holes is set according to the shell size and the force requirements. The bolts are sequentially inserted and locked into the bolt holes of each cover to ensure the connection reliability of the front cover 11, the middle cover 12 and the rear cover 13.

[0045] As an optional implementation, when the front cover 11, middle cover 12 and rear cover 13 are connected by snap-fit, the connecting surfaces of the front cover 11 and the middle cover 12, and the connecting surfaces of the middle cover 12 and the rear cover 13 are respectively provided with slots and protrusions. The shapes of the slots and protrusions are adapted to each other. During assembly, the slots and protrusions are elastically engaged to achieve quick connection. During disassembly, the protrusions and slots can be separated by external force, so as to facilitate the quick assembly, inspection and replacement of each component.

[0046] Specifically, the front cover 11 has a first wiring hole in its center, the middle cover 12 has a second wiring hole in its center, and the rear cover 13 has a third wiring hole in its center. The first, second, and third wiring holes are all coaxially arranged with the hollow shaft 4, and the diameter of the three holes is not less than the inner diameter of the hollow shaft 4, so as to ensure that the wire harness can be threaded through the hollow shaft 4 to complete the whole machine installation.

[0047] Furthermore, the front cover 11 has an annular first limiting part protruding into the housing. The first limiting part is integrally formed with the front cover 11, and its axis coincides with the housing axis. The inner diameter of the first limiting part is adapted to the outer diameter of the gear ring of the planetary transmission mechanism 2 described below, and the height of the first limiting part matches the axial thickness of the gear ring. The gear ring is embedded in the first limiting part and fixedly connected to the front cover 11. The fixing method includes, but is not limited to, interference fit, bolt connection, etc.

[0048] As an optional implementation, when the gear ring and the first limiting part are interference-fitted, the gear ring is pressed into the first limiting part by a press-fitting process, and the elastic deformation of the material is used to achieve a tight fit between the gear ring and the first limiting part.

[0049] As an optional implementation, when the gear ring and the first limiting part are connected by bolts, mounting holes are evenly arranged circumferentially on the end face of the gear ring, and threaded holes are provided at corresponding positions of the first limiting part. The bolt passes through the mounting holes of the gear ring and is screwed into the threaded holes to lock and fix the gear ring and the front cover 11. In addition to radially limiting the gear ring, the first limiting part also forms a positioning surface on its axial end face. One end face of the gear ring is tightly fitted with this positioning surface to achieve axial positioning of the gear ring, thereby preventing axial movement of the gear ring during transmission and thus preventing off-center load during the operation of the planetary transmission mechanism 2, which improves the smoothness of transmission. At the same time, the front cover 11 also has a protruding annular second limiting part on the side facing the drive mechanism. The second limiting part is coaxially arranged with the first limiting part, and its inner diameter is adapted to the outer diameter of the frameless motor 3. It is used to radially limit and axially position the frameless motor 3 to ensure the coaxiality of the frameless motor 3 and the planetary transmission mechanism 2, thereby achieving stable power transmission.

[0050] Specifically, the inner wall of the middle cover 12 is integrally formed with an annular partition. The axis of the partition coincides with the axis of the housing. This integral structure improves the overall stability of the housing and prevents deformation under stress. The partition divides the interior of the housing into two independent mounting cavities: the first mounting cavity accommodates the planetary transmission mechanism 2 and the drive mechanism, while the second mounting cavity accommodates the detection mechanism and the controller 6. This partitioning of functional components improves the overall structural compactness and reduces interference between different components. An axial positioning step is provided on the side of the partition facing the first mounting cavity. The end face of the positioning step fits against the end face of the frameless motor 3 (described below) to axially limit the component and prevent axial movement during operation. A clearance hole adapted to the hollow shaft 4 is provided in the center of the partition to ensure smooth passage of the hollow shaft 4. Several positioning bosses are also provided on the side of the partition facing the second mounting cavity. These bosses provide axial support and radial limiting for the controller 6, the detection mechanism, and the rear cover 13, thereby preventing displacement of internal components due to vibration during motor operation.

[0051] Specifically, the planetary transmission mechanism 2 includes a gear ring, a sun gear, and multiple planet gears. Each gear is made of high-strength, wear-resistant materials, including but not limited to high-strength alloy steel and carburized bearing steel, to ensure the overall structural strength and service life of the planetary transmission mechanism 2. The sun gear is located at the center of the planetary transmission mechanism 2, with a through hole at its center. This allows the hollow shaft 4 to pass through smoothly while maintaining relative rotation between the two, preventing frictional interference during operation. The gear ring is fixedly installed within the first limiting part of the front cover 11, forming a ring structure. Its inner wall has internal teeth, and the outer circumference of the sun gear has external teeth. Multiple planet gears are evenly distributed between the gear ring and the sun gear. The planet gears are rotatably connected to the planet carrier outside the housing via planetary shafts. One end of the hollow shaft 4 is coaxially fixedly equipped with an output flange, and the planet carrier is fixedly connected to this output flange. The outer circumference of the planet gears simultaneously meshes with the internal teeth of the gear ring and the external teeth of the sun gear, forming a planetary transmission meshing pair. The gear ring, sun gear, and planet gears all have involute tooth profiles. The meshing process of this gear profile is line contact, which has the characteristics of smooth transmission, strong load-bearing capacity, and high transmission efficiency. Moreover, there is no need to perform complex modifications such as equidistant, displacement, or rotation of the tooth profile. Mass production can be achieved by using conventional gear processing equipment such as gear hobbing machines and gear shaping machines in conjunction with standard hobbing cutters and gear shaping cutters.

[0052] As an optional implementation, the planetary transmission mechanism 2 is composed of two- or three-stage planetary sets coupled together. Each planetary set includes a sun gear and several corresponding planetary gears. The transmission ratio of a single-stage planetary set is set to a range of 1.5-3.5. By setting a reasonable number of gear teeth, the number of teeth on the sun gear can be made close to the number of teeth on the ring gear. This allows the sun gear to obtain a larger addendum circle and dedendum circle diameter, thereby ensuring that the through hole at the center of the sun gear can meet the space requirements for the wiring harness and the installation of the branching components, and avoiding the limitation of the through hole size affecting the realization of the hollow wiring function.

[0053] Specifically, the multi-stage planetary gear coupling method involves a fixed connection between the planet carrier of the previous stage planetary gear set and the sun gear of the next stage planetary gear set. Power is transmitted sequentially through each stage of the planetary gear set. By superimposing the transmission ratios of two or three stages of planetary gear sets, the required transmission ratio for the joint motor is achieved, thereby improving the torque output capability of the planetary joint motor and meeting the load requirements of the humanoid robot's joint movements. This planetary transmission mechanism 2 is a pure involute gear structure. Compared with the RV transmission structure of planetary gears and cycloidal gears in existing technologies, it does not require complex modification of the tooth profile, avoiding the problems of reduced load-bearing capacity and transmission accuracy deviation caused by improper modification. In terms of processing, it does not rely on special equipment such as high-precision grinding machines; conventional gear processing equipment can complete the production. The sources of processing errors are relatively simple and easy to control. In terms of inspection, accuracy can be tested using conventional gear inspection equipment such as gear runout meters and pitch meters, without the need for high-precision general-purpose inspection equipment such as coordinate measuring machines. This results in high inspection efficiency and lower requirements for the professional level of inspection personnel, reducing the design difficulty, manufacturing cost, and inspection cost of the planetary transmission mechanism 2, which is conducive to mass production and widespread application.

[0054] Specifically, the drive mechanism is a frameless motor 3 housed in the first mounting cavity. This frameless motor 3 is specifically an external rotor frameless motor 3, which improves its overall performance through magnetic circuit optimization and electromagnetic optimization. Magnetic circuit optimization includes, but is not limited to, using a Halbach array to arrange magnets and optimizing magnet thickness and pole pair number to reduce leakage flux loss and increase air gap flux density. Electromagnetic optimization includes, but is not limited to, using a distributed winding structure and optimizing winding wire diameter and number of turns to reduce copper and iron losses and achieve a motor energy conversion efficiency ≥90%. The frameless motor 3 is integrally encapsulated with epoxy resin. The encapsulation material is a high-temperature resistant and aging-resistant epoxy resin. The motor stator, windings, and leads are encapsulated using a vacuum encapsulation process to achieve moisture-proof, dust-proof, and electromagnetic radiation-proof protection, and to improve the overall structural integrity and heat dissipation performance of the motor.

[0055] Furthermore, the front cover 11 has an annular second limiting part protruding on the side facing the frameless motor 3. The second limiting part is integrally formed with the front cover 11, and its axis coincides with the axis of the housing. The inner diameter of the second limiting part is adapted to the outer diameter of the stator of the frameless motor 3 to ensure that there is no radial movement after the frameless motor 3 is installed. The axial height of the second limiting part matches the axial thickness of the stator of the frameless motor 3, and its end face fits against the end face of the stator of the frameless motor 3. The annular partition of the middle cover 12 fits against the other end face of the stator of the frameless motor 3, thereby forming an axial positioning for the frameless motor 3 and preventing axial displacement of the motor during operation. The frameless motor 3 is embedded in the second limiting part and is detachably fixedly connected to the front cover 11. The connection method includes, but is not limited to, bolt connection. Specifically, a number of mounting holes are evenly opened circumferentially on the end face of the stator of the frameless motor 3, and the front cover 11 has threaded holes at corresponding positions. Hexagonal socket head cap screws are passed through the mounting holes and screwed into the threaded holes to lock them in place. By radially limiting and axially positioning the frameless motor 3, the high-precision coaxiality of the frameless motor 3 and the sun gear of the planetary transmission mechanism 2 is ensured, thereby avoiding off-center load or impact during power transmission, and thus ensuring transmission smoothness and component service life.

[0056] Furthermore, the output end of the frameless motor 3 is connected to the sun gear via a drive connection, which includes, but is not limited to, keyed connection, splined connection, or interference fit. Specifically, when using a keyed connection, a keyway is provided at the output shaft end of the outer rotor of the frameless motor 3, and a corresponding keyway is provided in the mounting hole of the sun gear. Torque transmission is achieved by embedding a flat key or a semi-circular key into the double slot. When using a splined connection, a rectangular spline or an involute spline is selected, and torque is transmitted through tooth surface meshing. When using an interference fit, the outer rotor of the frameless motor 3 and the sun gear are fitted together through a heat fitting or press fitting process.

[0057] Specifically, the hollow shaft 4 is made of aluminum alloy or alloy steel, and its axis coincides with the axis of the housing. One end of the hollow shaft 4 is coaxially and fixedly connected to the output flange on the outside of the housing. The connection method includes, but is not limited to, welding or bolt locking. Specifically, when welding is used, the hollow shaft 4 and the output flange are welded together by argon arc welding; when bolt locking is used, several bolt holes are evenly arranged circumferentially on the end face of the output flange, and a flange is provided at the corresponding end of the hollow shaft 4. Bolts are passed through the flange and locked to the output flange. The side of the output flange facing the planetary transmission mechanism 2 is fixedly connected to the planet carrier of the planetary transmission mechanism 2 by bolts. The planet shaft on the planet carrier rotates and engages with multiple planet gears. The planet gears drive the planet carrier and the output flange to rotate through meshing transmission, thereby outputting the power transmitted by the planetary transmission mechanism 2 to the robot joint components. Optionally, the other end of the hollow shaft 4 is supported on the rear cover 13 by a deep groove ball bearing. The inner ring of the bearing is interference-fitted with the hollow shaft 4, and the outer ring is interference-fitted with the bearing seat hole of the rear cover 13. The end of the hollow shaft 4 is provided with a chamfer of 15°-30° to avoid scratching damage to the wire harness passing through it.

[0058] Furthermore, the output flange, fixedly connected to the hollow shaft 4, also serves as an impact-resistant power output end cover. It is made of high-strength alloy material, and its disc surface is equipped with radial reinforcing ribs to enhance its structural rigidity. The output flange is supported by a crossed roller bearing. The inner ring of the crossed roller bearing is interference-fitted with the outer circumference of the output flange, and the end face of the inner ring fits against the output flange, forming axial positioning and preventing the inner ring from moving relative to the output flange. The outer ring of the crossed roller bearing is interference-fitted with the corresponding mounting hole of the front cover 11. This support structure can effectively resist the axial and radial impacts of external forces on the joint motor. When the robot performs violent movements or accidentally falls, the crossed roller bearing can evenly transfer the impact load to the housing, preventing damage to internal components due to excessive local stress, thereby ensuring the operational stability of the joint motor.

[0059] Specifically, the detection mechanism is a hollow angle encoder 5, which is a thin-walled inductive angle encoder with a through hole in its middle for the hollow shaft 4 to pass through. The hollow angle encoder 5 includes a stator and two rotors. The stator is fixedly installed in the second mounting cavity. One rotor is fixedly connected to the output end of the frameless motor 3 and rotates synchronously with the output end of the frameless motor 3 to collect the motion parameters of the output end of the frameless motor 3, including but not limited to speed and angle. The other rotor is fixedly connected to the hollow shaft 4 and rotates synchronously with the hollow shaft 4 and the output flange to collect the motion parameters of the output flange. By sensing the changes in the electromagnetic field of the two rotors, the stator can realize the position memory function of multiple absolute values ​​after the planetary joint motor is powered off, thereby providing data support for the control of the joint motor.

[0060] Specifically, controller 6 is a PCB assembly with a central opening to avoid the hollow shaft 4. It also functions as a hollow actuator with over-temperature, over-voltage, and overload protection functions, capable of cutting off power or issuing alarm signals under abnormal operating conditions to ensure the safe operation of the articulated motor. Controller 6 is electrically connected to the drive mechanism and detection mechanism via wires. It receives motion parameters collected by the detection mechanism and outputs control signals to the drive mechanism according to preset control logic, thereby adjusting the output speed and torque of the drive mechanism to achieve closed-loop control of the articulated motor.

[0061] Furthermore, the controller 6 is equipped with a connection component, which includes several connectors 61 for connecting power lines and signal lines. Each connector 61 has a receiving end and an output end. The receiving end is used to receive DC power from the power battery and control command signals from the main control board, and the output end is used to export the DC power and control command signals to other joint motors, thereby realizing the series connection of multiple joint motors. Each joint motor connected in series can simultaneously receive current from the power battery through the connector 61 and independently receive control commands from the main control board. The rear cover 13 has clearance holes corresponding to the positions of the connectors 61. The size of the clearance holes is adapted to the shape of the connectors 61 to provide installation and clearance space for the connectors 61, facilitating the connection of the connectors 61 with external wiring or connectors 61 of other joint motors, thereby realizing the centralized arrangement of the entire wiring harness.

[0062] Specifically, the wiring harness assembly includes a cylinder, separators, and bearings, which work together to achieve the separation and arrangement of the wiring harness. The cylinder is made of lightweight, high-strength insulating materials, including but not limited to engineering plastics and glass fiber reinforced nylon, which reduces overall weight and avoids electromagnetic interference. The outer diameter of the cylinder matches the inner diameter of the hollow shaft 4, and it passes through the hollow shaft 4. A preset gap is maintained between the outer wall of the cylinder and the inner wall of the hollow shaft 4. This gap prevents frictional interference during relative rotation and provides space for airflow to aid heat dissipation. One end of the cylinder is coaxially fixed to the rear cover 13, with connection methods including but not limited to bolt connections. Specifically, the end of the cylinder has an annular mounting flange with several bolt holes evenly distributed circumferentially. Bolts are used to lock the flange to the corresponding threaded holes of the rear cover 13. The fixing of the cylinder to the rear cover 13 ensures that the axis of the cylinder coincides with the axis of the hollow shaft 4, preventing uneven stress on the wiring harness caused by misalignment of the wiring harness assembly.

[0063] Furthermore, the separator is made of materials with excellent insulation and wear resistance, including but not limited to polycarbonate and insulating rubber. Its extension direction is consistent with the axis of the cylinder, and its axial length matches the internal length of the cylinder. The separator is fixed to the cylinder by methods including but not limited to integral injection molding or snap-fit ​​connection. The separator divides the interior of the cylinder into independent high-voltage and low-voltage chambers. The cross-sectional dimensions of the two chambers can be allocated according to the specific number and specifications of the wire harnesses. The high-voltage chamber is used to arrange power lines, including but not limited to power battery power lines, and the low-voltage chamber is used to arrange signal lines, including but not limited to control command lines and detection signal lines. This avoids interference from the electromagnetic field generated by the high-voltage lines on the low-voltage signals and also prevents wear or short circuit risks caused by compression or entanglement between wire harnesses. Optionally, the two side walls of the separator are provided with arc-shaped grooves, the radius of which is adapted to the outer diameter of the corresponding wire harness, to limit the bundled wire harnesses and prevent them from moving within the chamber.

[0064] Furthermore, deep groove ball bearings are selected to accommodate the relative rotation requirements between the cylinder and the hollow shaft 4. The inner diameter of the bearing is fitted with the outer diameter of the cylinder, and the outer diameter is fitted with the inner diameter of the hollow shaft 4 using an interference fit. The bearing is located at the end of the cylinder away from the rear cover 13. The inner ring of the bearing is coaxially fixed to the outer wall of the cylinder via an interference fit, and the outer ring is coaxially fixed to the inner wall of the hollow shaft 4 via an interference fit. Optionally, the bearing is pre-filled with long-life grease, including but not limited to lithium-based grease, to reduce rotational friction loss and extend service life. Sealing caps are provided at both ends of the bearing to prevent dust and moisture from entering. This bearing not only provides support to the end of the cylinder away from the rear cover 13, balancing the forces at both ends of the cylinder and preventing deformation or swaying due to cantilever installation, but also enables low-resistance relative rotation between the cylinder and the hollow shaft 4. This ensures that when the hollow shaft 4 drives the output flange to rotate, the cylinder and internal wiring harness remain stationary, thereby preventing frictional wear between the wiring harness and the inner wall of the hollow shaft 4.

[0065] Furthermore, a metal shielding mesh is installed inside the weak current cavity. The material of the metal shielding mesh includes, but is not limited to, electromagnetic shielding materials such as copper mesh, phosphor bronze mesh, and stainless steel mesh. The metal shielding mesh extends along the axial direction of the separator, covering at least the entire length of the weak current cavity, and is tightly fitted to the inner wall of the weak current cavity, specifically fixed by embedding or bonding. One end of the metal shielding mesh extends to the connection between the cylinder and the rear cover 13, and is grounded to the shell through a conductive connector, forming a complete shielding circuit. Preferably, the outer surface of the metal shielding mesh is provided with an insulating coating, including but not limited to a polyurethane coating, to prevent the shielding mesh from scratching the signal line insulation layer. In addition, the axial ends of the metal shielding mesh are provided with a smoothly transitioned flange structure to further avoid damage to the wire harness sheath.

[0066] In a second aspect, a humanoid robot is proposed, comprising a robot body and the aforementioned hollow integrated planetary joint motor. The robot body includes a head, torso, limbs, and joint connectors. The specific number of joint motors is configured according to the robot's required degrees of freedom of movement, corresponding to the head rotation joint, torso pitch joint, shoulder joint, elbow joint, wrist joint, hip joint, knee joint, and ankle joint. The joint motors are coaxially fixedly connected to the joints of the robot body via output flanges. The joint motors drive the corresponding joints of the robot body to perform rotation, pitch, and swing movements, adapting to the humanoid robot's need to mimic human limb movements.

[0067] Furthermore, several joint motors are connected in series via connectors 61 on their respective controllers 6. The robot's torso houses a power battery and a main control board. The power battery provides DC power to the entire robot, while the main control board outputs unified control commands. The wiring harness can be arranged in two ways. One method involves the wiring harness entering from the rear cover 13 of the head joint motor (e.g., the joint motor near the head on the torso), passing through the strong and weak current chambers of the wiring assembly, then running along the hollow shaft 4 through the entire joint motor, sequentially through the hollow channels of each series-connected joint motor, and finally exiting through the front cover 11 of the foot joint motor, forming a continuous wiring harness loop.

[0068] Preferably, another arrangement of the overall wiring harness is to transmit power and signals between the series-connected joint motors through connectors 61. That is, the output connector 61 of the previous joint motor is connected to the receiving connector 61 of the next joint motor. The output connector 61 integrates an output power line 73 and an output signal line 74, and the receiving connector 61 integrates an input power line 72 and an input signal line 71. After connection, the output power line 73 of the previous joint motor is connected to the input power line 72 of the next joint motor, and the output signal line 74 of the previous joint motor is connected to the input signal line 71 of the next joint motor, without the need for additional independent wiring harnesses. Each joint motor receives current from the power battery through the input power line 72 of its own receiver connector 61, and receives control commands from the main control board through the input signal line 71 of its receiver connector 61. Simultaneously, it can export the power battery current to the next adjacent joint motor through the output power line 73 of its own output connector 61, and export the main control board's control commands to the next adjacent joint motor through the output signal line 74 of its output connector 61. This eliminates the need for each joint motor to be directly connected to the battery and main control board via a separate wiring harness, thereby reducing the number and length of the overall wiring harness and simplifying its arrangement. This arrangement not only reduces the risk of entanglement, friction, and wear of the input power line 72, input signal line 71, output power line 73, and output signal line 74 during robot movement, but also reduces the weight of the robot body, lowers assembly difficulty and maintenance costs, reduces the space occupied by various wiring harnesses, and improves the robot's movement flexibility.

[0069] The operation of the hollow integrated planetary joint motor is as follows: First, the main control board sends a control signal to the controller 6 of the target joint motor through the serial connector 61 according to the preset motion program or external command. After receiving the signal, the controller 6 starts the frameless motor 3. After starting, the frameless motor 3 outputs power, which is transmitted to the sun gear through the transmission connection structure between its output end and the sun gear, driving the sun gear to rotate around the housing axis. Since the sun gear meshes with multiple planet gears, and the planet gears mesh with a fixed gear ring at the same time, the rotation of the sun gear drives multiple planet gears to revolve around the gear ring, while the planet gears themselves rotate around the planet axis. The revolution of the planet gears is transmitted to the output flange through the planet carrier, driving the output flange to rotate synchronously around the housing axis. The output flange is then fixedly connected to the robot joint to drive the robot joint to complete the corresponding rotation, pitch or swing motion.

[0070] During this power transmission process, the hollow angle encoder 5 operates synchronously. One rotor is fixedly connected to the output end of the frameless motor 3 and rotates synchronously with the output end of the frameless motor 3, collecting the motion parameters of the frameless motor 3, including but not limited to the output speed and rotation angle. The other rotor is fixedly connected to the hollow shaft 4 and rotates synchronously with the hollow shaft 4 and the output flange, collecting the actual output motion parameters of the joint motor, including but not limited to the speed, rotation angle, and position information of the output flange. The encoder stator senses the changes in the electromagnetic field of the two rotors, converts the collected mechanical motion parameters into electrical signals, and transmits them to the controller 6 in real time. After receiving the feedback signal from the detection mechanism, the controller 6 compares and analyzes it with the preset parameters sent by the main control board, generates adjustment commands according to the preset control logic, outputs corresponding control signals to the frameless motor 3, adjusts the input current of the frameless motor 3, and thus changes the output speed and torque of the frameless motor 3, thereby realizing closed-loop control of the joint movement and ensuring that the joint movement trajectory is consistent with the preset program.

[0071] If the controller 6 detects abnormal operating conditions, including but not limited to the frameless motor 3 or its own operating temperature exceeding the preset threshold, abnormal power supply voltage, output load exceeding the rated load, or abnormal fluctuations in motion parameters collected by the detection mechanism, the controller 6 triggers the protection function, automatically cuts off the power supply to the frameless motor 3 or sends an alarm signal to the main control board to prevent damage to components due to abnormal operating conditions and ensure the safe operation of the joint motor and the robot as a whole.

[0072] Meanwhile, the entire wiring harness is routed through a branching assembly within the hollow shaft 4. The power lines are located in the high-voltage cavity, while the signal lines are located in the low-voltage cavity equipped with a metal shielding mesh, achieving physical separation and electromagnetic shielding of the wiring harness. When the robot's joints move, the hollow shaft 4 rotates with the output flange, while the cylinder of the branching assembly rotates relative to the hollow shaft 4 via bearings. The cylinder and the internal wiring harness remain stationary, and the wiring harness moves synchronously with the robot's limbs along the hollow channel, preventing entanglement due to joint rotation and avoiding friction with the inner wall of the hollow shaft 4 or external components. Multiple series-connected joint motors transmit power and control commands step-by-step through connector 61. The current from the power battery is supplied to each joint motor through the high-voltage channel, while the control commands from the main control board are transmitted to each target joint motor through the low-voltage channel, thereby ensuring the coordination of the robot's joint movements and assisting the humanoid robot in performing complex actions.

[0073] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0074] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A hollow integrated planetary joint motor, characterized in that, include: case; A planetary transmission mechanism is disposed within the housing. The planetary transmission mechanism includes a ring gear, a sun gear, and multiple planet gears. A through hole is provided at the center of the sun gear. A drive mechanism is disposed within the housing and is connected to the sun gear via a transmission. A hollow shaft passes through the housing, the planetary transmission mechanism, and the drive mechanism along the axial direction of the housing to form a wire harness channel. One end of the hollow shaft is coaxially fixed with an output flange, which is connected to multiple planetary gears. A wire splitter assembly is disposed within the hollow shaft to separate and arrange the wire harness within the hollow shaft.

2. The hollow integrated planetary joint motor according to claim 1, characterized in that, The housing includes a front cover, a middle cover, and a rear cover; The front cover, middle cover and rear cover are detachably connected along the axial direction of the housing. The front cover has a first wiring hole at its center, the middle cover has a second wiring hole at its center, and the rear cover has a third wiring hole at its center. The first wiring hole, the second wiring hole and the third wiring hole are coaxially arranged with the hollow shaft. The front cover has an annular first limiting part protruding into the housing, and the toothed ring is embedded in the first limiting part and fixedly connected to the front cover; The inner wall of the middle cover is integrally formed with an annular partition, which divides the interior of the housing into a first mounting cavity and a second mounting cavity.

3. The hollow integrated planetary joint motor according to claim 1, characterized in that, The gear ring, the sun gear, and the planet gears all have involute tooth profiles.

4. The hollow integrated planetary joint motor according to claim 2, characterized in that, The drive mechanism is a frameless motor disposed in the first mounting cavity; The front cover has an annular second limiting part protruding on the side facing the frameless motor, and the frameless motor is embedded in the second limiting part and is detachably and fixedly connected to the front cover. The output end of the frameless motor is connected to the sun gear drive.

5. The hollow integrated planetary joint motor according to claim 4, characterized in that, The joint motor also includes a detection mechanism disposed within the second mounting cavity; The detection mechanism is a hollow angle encoder, which includes a stator and two rotors. One rotor is connected to the output end of the frameless motor to collect the motion parameters of the output end of the frameless motor, and the other rotor is connected to the hollow shaft to collect the motion parameters of the output flange.

6. The hollow integrated planetary joint motor according to claim 5, characterized in that, The joint motor also includes a controller disposed within the second mounting cavity; The controller is a PCB assembly with a central opening. The controller is electrically connected to the drive mechanism and the detection mechanism, and controls the operation of the drive mechanism.

7. The hollow integrated planetary joint motor according to claim 6, characterized in that, The controller is provided with a connection component, which includes several connectors for connecting power lines and signal lines to receive power and signals and to connect multiple joint motors in series. The rear cover has a clearance hole corresponding to the position of the connector.

8. The hollow integrated planetary joint motor according to claim 6, characterized in that, The branching component includes: A cylindrical body is inserted into the hollow shaft and spaced apart from the hollow shaft, with one end of the cylindrical body fixedly connected to the rear cover; A separator is disposed inside the cylinder and divides the cylinder into a high-voltage cavity and a low-voltage cavity to separate and arrange the power lines and signal lines. A bearing is disposed at one end of the cylinder away from the rear cover. The outer ring and inner ring of the bearing are coaxially and fixedly connected to the hollow shaft and the cylinder, respectively, to support the cylinder.

9. The hollow integrated planetary joint motor according to claim 8, characterized in that, A metal shielding mesh is provided inside the weak current cavity, and the metal shielding mesh extends along the axial direction of the separator.

10. A humanoid robot, characterized in that, Includes the robot body and several hollow integrated planetary joint motors as described in any one of claims 1-9; The joint motors are connected to the joints of the robot body, and several joint motors are connected in series.

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