Frameless motor

Abstract

The application discloses a frameless motor, which comprises a rotor assembly and a stator assembly. The rotor assembly comprises a rotating shaft and a rotor structure, and the rotating shaft is arranged on the rotor structure. The stator assembly comprises a stator structure and a coil winding component, the stator structure is a slotless ring structure and is arranged around the rotor structure in the circumferential direction, and the coil winding component is arranged on the stator structure. Thus, the frameless motor provided by the application adopts the slotless ring structure as the stator structure, and completely discards the design that the teeth and the slots are alternately arranged in the traditional stator core. Since the surface of the stator is continuous and smooth, there is no physical basis for the periodic change of the magnetic conductance, and therefore, the generation mechanism of the cogging torque is fundamentally eliminated. In the low-speed or high-precision control scene, the output torque of the frameless motor is more stable, and the smoothness of operation and the accuracy of control response are significantly improved.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to a frameless motor. Background Technology

[0002] Frameless motors, as highly integrated power components, are widely used in fields with stringent requirements for space and performance, such as robot joints and precision instruments. In existing technologies, frameless motor designs generally employ a stator core structure with slots, in which the windings are embedded.

[0003] However, this slotted structure has inherent drawbacks: First, due to the alternating presence of teeth and slots on the stator core, the magnetic permeability between the stator and rotor permanent magnets changes periodically when the rotor rotates, generating undesirable cogging torque. This cogging torque causes torque fluctuations in the motor at low speeds, affecting operational smoothness and control accuracy. Second, the presence of slots limits the effective filling space of the windings, resulting in a low slot fill factor, which restricts further improvement in motor torque performance within a limited motor volume. Therefore, existing technologies urgently need to address the technical problems of poor operational smoothness and limited torque density caused by the cogging effect. Summary of the Invention

[0004] This application provides a frameless motor that can solve at least one of the above-mentioned technical problems.

[0005] This application provides a frameless motor, including: A rotor assembly includes a shaft and a rotor structure, wherein the shaft is disposed on the rotor structure; The stator assembly includes a stator structure and a coil winding component. The stator structure is a slotless annular structure and is arranged circumferentially around the rotor structure. The coil winding component is disposed on the stator structure.

[0006] In some embodiments, the stator structure has an inner ring surface and an outer ring surface arranged opposite to each other, and the coil winding component is disposed on the inner ring surface.

[0007] In some implementations, the inner and outer annular surfaces are coaxially arranged.

[0008] In some embodiments, the frameless motor also includes an adhesive element, through which the coil winding components are disposed on the inner annular surface.

[0009] In some embodiments, the coil winding component includes at least one coil winding, with all coil windings disposed on the inner annular surface of the stator structure.

[0010] In some embodiments, there are multiple coil windings, which are arranged sequentially at intervals along the circumference of the inner toroidal surface.

[0011] In some embodiments, the rotor structure is provided with a mounting through hole that extends through the rotor structure along its axial direction, and the rotor shaft passes through the mounting through hole.

[0012] In some implementations, the rotor structure is a permanent magnet rotor structure.

[0013] In some implementations, the stator structure is a slotless annular core.

[0014] In some implementations, the frameless motor also includes a wiring assembly and a PCB board, with the wiring assembly electrically connected to the coil winding components via the PCB board.

[0015] This application provides a frameless motor, which includes a rotor assembly and a stator assembly. The rotor assembly includes a shaft and a rotor structure, with the shaft disposed on the rotor structure. The stator assembly includes a stator structure and coil winding components. The stator structure is a slotless annular structure arranged circumferentially around the rotor structure, and the coil winding components are disposed on the stator structure. Thus, the frameless motor provided by this application uses a slotless annular structure as its stator structure, completely eliminating the traditional design of alternating teeth and slots in the stator core. Because the stator surface is continuously smooth, there is no physical basis for periodic changes in magnetic permeability, thus fundamentally eliminating the mechanism for generating cogging torque. In low-speed or high-precision control scenarios, the frameless motor outputs more stable torque, significantly improving the smoothness of operation and the accuracy of control response. Furthermore, traditional slotted stators are limited by the tooth structure, and the windings can only be embedded in a limited slot space, resulting in a low slot fill factor and limiting the amount of copper wire used per unit volume. This application places the coil winding components directly on the slotless annular stator structure, freeing the winding arrangement from the constraints of tooth and slot geometry, thus enabling a more flexible and denser winding method. This increases the effective conductor cross-sectional area and ampere-turns, significantly enhancing the electromagnetic torque output capability of the frameless motor within the same external dimensions, thereby increasing the overall torque density and meeting the design requirements for high power density. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the frameless motor provided in an embodiment of this application.

[0018] Explanation of icon numbers: 10. Frameless motor; 100. Rotor assembly; 110. Shaft; 120. Rotor structure; 121. Mounting through hole; 200. Stator assembly; 210. Stator structure; 211. Inner annular surface; 212. Outer annular surface; 220. Coil winding assembly; The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0020] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0021] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0022] Unless otherwise defined, 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 belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] Please see Figure 1This embodiment provides a frameless motor 10. The frameless motor 10 includes a rotor assembly 100 and a stator assembly 200. Specifically, the rotor assembly 100, as the rotating part of the frameless motor 10, is mainly used for outputting torque. The rotor assembly 100 includes a rotating shaft 110 and a rotor structure 120, with the rotating shaft 110 disposed on the rotor structure 120. The rotating shaft 110 is located on the central axis of the rotor assembly 100, runs through the entire frameless motor 10 structure, and serves as the core component for power output. The rotor structure 120 is fixedly connected to the rotating shaft 110 and rotates together with the rotating shaft 110. It should be understood that although this embodiment shows the relative positional relationship between the rotating shaft 110 and the rotor structure 120, in other embodiments, the rotating shaft 110 may also be integrally formed with the rotor structure 120, or fixed by means of key connection, interference fit, etc., as long as synchronous rotation and torque transmission can be achieved.

[0024] The stator assembly 200, as the stationary part of the motor, is mainly used to generate the driving magnetic field. The stator assembly 200 includes a stator structure 210 and a coil winding component 220. In this embodiment, the stator structure 210 is a slotless annular structure and is arranged circumferentially around the rotor structure 120, and the coil winding component 220 is disposed on the stator structure 210.

[0025] Specifically, the "slotless" feature of the stator structure 210 refers to the absence of slot openings on its surface, as found in traditional motors, used to accommodate windings. The stator core of a conventional slotted motor is typically formed by laminations, with inward or outward protruding teeth forming slots. This structure leads to uneven air gap permeability, resulting in cogging torque. In contrast, the stator structure 210 in this embodiment employs a slotless annular structure with smooth, continuous curved surfaces on both its inner and outer surfaces, free from the undulations of slots. This geometric feature ensures that the air gap permeability between the stator and rotor remains constant in the circumferential direction, fundamentally eliminating the cogging effect caused by changes in magnetic reluctance.

[0026] Furthermore, the stator structure 210 is arranged circumferentially around the rotor structure 120, forming a concentric stacked structure. Specifically, the stator structure 210 is cylindrically sleeved outside the rotating shaft 110 and located on the outer side of the rotor structure 120. This circumferential arrangement allows the magnetic field generated by the coil winding component 220 to act uniformly on the circumference of the rotor structure 120, forming a highly efficient magnetic coupling circuit.

[0027] The coil winding component 220 is disposed on the stator structure 210 and is used to generate an excitation magnetic field when energized. Since the stator structure 210 is slotless, the coil winding component 220 can be directly attached to or fixed to the surface of the stator structure 210 (such as the inner annular surface 211 or the outer annular surface 212) without being confined to narrow slots. This arrangement not only simplifies the stator manufacturing process but also increases the space for coil winding arrangement.

[0028] Through the above structural design, the frameless motor 10 of this embodiment achieves significant technical effects. First, because the stator structure 210 adopts a slotless annular design, the inherent cogging effect of traditional slotted structures is eliminated, resulting in a significant reduction in torque fluctuations during low-speed operation of the frameless motor 10. This greatly improves the smoothness and control accuracy of the frameless motor 10, making it particularly suitable for applications such as humanoid robots where low-speed stability is extremely important. Second, the slotless structure makes the magnetic circuit of the stator structure 210 smoother, reducing magnetic reluctance and eddy current losses caused by cogging, and improving the energy conversion efficiency of the frameless motor 10. In addition, the smooth air gap surface also helps to reduce noise and vibration during operation of the frameless motor 10, improving overall performance.

[0029] The frameless motor 10 provided in this application adopts a slotless annular structure as the stator structure 210, completely abandoning the traditional stator core design with alternating teeth and slots. Since the stator surface is continuously smooth and there is no physical basis for periodic changes in magnetic permeability, the mechanism for generating cogging torque is fundamentally eliminated. In low-speed or high-precision control scenarios, the frameless motor 10 outputs a more stable torque, significantly improving the smoothness of operation and the accuracy of control response. Furthermore, traditional slotted stators are limited by the tooth structure, and the windings can only be embedded in a limited space within the slots, resulting in a low slot fill factor and limiting the amount of copper wire used per unit volume. In contrast, this application directly sets the coil winding component 220 on the slotless annular stator structure 210, and the winding arrangement is no longer constrained by the tooth and slot geometry, allowing for more flexible and denser winding methods. This increases the effective conductor cross-sectional area and ampere-turns, significantly improving the electromagnetic torque output capability of the frameless motor 10 within the same external dimensions, thereby increasing the overall torque density and meeting the requirements of high power density design.

[0030] In some embodiments, the stator structure 210 has an inner annular surface 211 and an outer annular surface 212 arranged opposite to each other, and the coil winding component 220 is disposed on the inner annular surface 211. Specifically, the inner annular surface 211 of the stator structure 210 refers to the annular surface facing the rotor structure 120, and the outer annular surface 212 refers to the annular surface away from the rotor structure 120. The inner annular surface 211 and the outer annular surface 212 can be coaxially arranged, that is, the inner annular surface 211 and the outer annular surface 212 are concentric rings and parallel to each other. This double annular surface design allows the coil winding component 220 to be closer to the rotor structure 120, thereby shortening the transmission path of the magnetic field lines and enhancing the magnetic field coupling efficiency. For example, in the illustrated embodiment, the inner annular surface 211 of the stator core directly forms an air gap with the outer surface of the rotor structure 120, while the outer annular surface 212 serves as a support structure. This arrangement ensures both the compactness of the magnetic circuit and provides a stable mounting base for the coil winding.

[0031] Furthermore, the frameless motor 10 also includes an adhesive component, through which the coil winding component 220 is mounted on the inner ring surface 211. In this embodiment, the adhesive component is preferably epoxy resin, which has excellent insulation properties, mechanical strength, and temperature resistance, ensuring that the coil winding component 220 remains firmly fixed under high-speed motor operation and temperature change environments. The specific process includes: firstly, cleaning the inner ring surface 211 of the stator structure 210 to remove oil and oxide layers; then uniformly coating the inner ring surface 211 with epoxy resin, controlling the thickness within a preset range; next, precisely placing the pre-wound coil winding component 220 in the adhesive application area, and applying a preset pressure using a special tooling to fully impregnate the coil and core surfaces with the adhesive layer; finally, curing at a preset temperature for a period of time to form a high-strength adhesive layer. Compared with traditional welding or mechanical fixing, this bonding method not only avoids damage to the coil insulation layer caused by high temperatures but also reduces assembly stress, significantly improving the reliability and lifespan of the frameless motor 10.

[0032] As another alternative implementation, the adhesive can also be made of silicone gel or polyimide adhesive to meet the needs of different operating temperatures and vibration environments. For example, in high-temperature applications (such as above 150°C), high-temperature resistant polyimide adhesive can be selected, with a long-term operating temperature of over 200°C; while in high-vibration environments, silicone gel, due to its excellent elastic buffering properties, can effectively absorb vibration energy and prevent coil fatigue fracture.

[0033] The coil winding component 220 includes at least one coil winding, all of which are disposed on the inner annular surface 211 of the stator structure 210. For example, the number of coil windings can be one; or, for example, the number of coil windings can be multiple. Multiple coil windings are arranged sequentially at intervals along the circumference of the inner annular surface 211. Specifically, the coil winding component 220 consists of 3-12 independent coil windings, which are uniformly distributed along the circumference of the stator structure 210, with a predetermined spacing between adjacent coil windings. For example, six coil windings are uniformly arranged on the circumference of the stator core, each coil winding occupying an arc length of approximately 60°, with the spacing area used for heat dissipation and insulation. This interleaved arrangement brings multiple technical benefits: First, in terms of heat dissipation, the interleaved areas form natural ventilation channels, which, together with the airflow generated during motor operation, can effectively remove the heat generated by the coils, reducing the coil operating temperature and thus extending the service life of the insulation materials; Second, in terms of magnetic field uniformity, the interleaved arrangement allows the magnetic fields generated by each coil winding to superimpose, forming a near-sine wave rotating magnetic field, reducing higher harmonic components, lowering motor torque pulsation, and significantly improving the smoothness of low-speed operation; In addition, this structure facilitates independent maintenance and replacement of the windings. When a coil winding fails, it can be disassembled individually without affecting other windings, reducing maintenance costs.

[0034] As another alternative implementation, the coil windings can also be arranged in a non-uniform spacing manner. For example, the spacing can be reduced in areas where the magnetic field strength requirement is high, while the spacing can be increased in areas where the heat dissipation requirement is high, so as to achieve an optimized balance between magnetic field distribution and heat dissipation performance.

[0035] It should be understood that although this embodiment describes the specific form in which the coil winding component 220 is fixed to the inner ring surface 211 by an adhesive and arranged in a circumferentially spaced manner, in other embodiments, the coil winding component 220 can also be fixed by means of buckles, straps or welding, and the arrangement can also be adjusted to an interlaced or spiral pattern according to the magnetic field design requirements, as long as stable magnetic field generation and effective heat dissipation can be achieved.

[0036] In some embodiments, the rotor structure 120 is provided with a mounting through hole 121, which extends through the rotor structure 120 along its axial direction, and the rotating shaft 110 passes through the mounting through hole 121. Specifically, the mounting through hole 121 is a through hole opened along the central axis of the rotor structure 120, and its shape is adapted to the cross-sectional shape of the rotating shaft 110, typically a cylindrical through hole. The rotating shaft 110 passes through the mounting through hole 121 and is fixedly connected to the rotor structure 120 by means of interference fit, key connection, or adhesive bonding, forming a coaxial rotating whole. The core advantage of this coaxial through-hole structure is that it can maximize the coaxiality between the rotating shaft 110 and the rotor structure 120. When the frameless motor 10 rotates at high speed, the deviation in coaxiality is the main source of centrifugal force and vibration. This embodiment utilizes a through-hole design 121 and precision machining processes (such as boring or grinding) to ensure that the fit tolerance between the hole diameter and the outer diameter of the rotating shaft 110 is within the micrometer range, thereby effectively eliminating periodic magnetic pull fluctuations caused by eccentricity. This not only significantly reduces noise and vibration during motor operation but also greatly improves operational stability, enabling the frameless motor 10 to output extremely stable torque during low-speed fine-tuning, which is crucial for the precise control of the finger joints of a humanoid robot.

[0037] As another alternative implementation, the fixing method between the shaft 110 and the rotor structure 120 is not limited to an interference fit. For example, in applications requiring the transmission of larger torques, a flat key or spline groove can be machined on the shaft 110, and a corresponding keyway can be machined on the inner wall of the mounting through hole 121 in the rotor structure 120. Reliable torque transmission can be achieved through a key connection. Furthermore, to further reduce weight and optimize rotational inertia, the shaft 110 can also be designed as a hollow shaft structure, meaning that the shaft 110 also has an axial through hole inside. This design effectively reduces the rotor's rotational inertia while ensuring strength, thereby improving the response speed of the frameless motor 10.

[0038] In some embodiments, the rotor structure 120 is a permanent magnet rotor structure 120. Specifically, the permanent magnet rotor structure 120 refers to a rotor structure 120 that uses permanent magnet materials (such as NdFeB, ferrite, or samarium cobalt) to generate a constant magnetic field. The permanent magnet rotor structure 120 eliminates the need for excitation windings and corresponding brush and slip ring structures. By eliminating the excitation windings, copper losses are completely eliminated, significantly reducing motor energy consumption and improving overall efficiency. This is particularly beneficial in battery-powered humanoid robot applications, effectively extending runtime. Secondly, the brushless structure avoids mechanical friction and wear between brushes and slip rings, reducing maintenance requirements and eliminating spark interference caused by poor brush contact, thus improving motor reliability in complex electromagnetic environments. Finally, permanent magnets provide high air gap magnetic flux density, resulting in a significant increase in torque density and power density within the same volume.

[0039] Furthermore, the permanent magnet rotor structure 120 can take various forms. For example, a surface-mount structure can be used, where the permanent magnet is directly attached to the surface of the rotor core (or rotor yoke). This structure is simple to manufacture and has a low magnetic leakage coefficient. Alternatively, an embedded structure can be used, where the permanent magnet is embedded in a slot inside the rotor core. This structure effectively prevents the permanent magnet from flying out during high-speed rotation and utilizes reluctance torque to increase output power. In this embodiment, considering the high requirements for space utilization and stability of the frameless motor 10, high-performance sintered NdFeB magnets are preferably used and fixed to the rotor yoke with a high-strength adhesive (such as high-temperature resistant epoxy resin) to form a stable magnetic field source. This design ensures that the magnetic field strength attenuation is minimal during long-term operation, thereby guaranteeing the long-term stability of the output torque.

[0040] In some embodiments, the stator structure 210 is a slotless annular core. Specifically, a slotless annular core refers to a circular ferromagnetic component made of a magnetically conductive material (such as silicon steel sheets, soft magnetic composite materials, or amorphous alloys) with no slots for embedding windings on its surface. Compared with conventional slotted cores, the stator structure 210 in this embodiment has significant geometric features: its outer diameter profile and inner hole profile are both complete circles, and the centers of these two circles are located at the same point, i.e., maintaining strict concentricity. This smooth annular structure eliminates the alternating distribution of teeth and slots on conventional stator cores, resulting in a uniform annular air gap between the inner surface of the stator and the outer surface of the rotor.

[0041] Traditional slotted frameless motors 10 suffer from uneven distribution of air gap magnetic permeability along the circumference due to slots in the stator core. When the rotor rotates, the magnetic reluctance fluctuates periodically with position changes, resulting in cogging torque. This cogging torque is the primary cause of vibration, noise, and speed fluctuations at low speeds, severely impacting the stability requirements of precision equipment such as humanoid robots. In contrast, the slotless annular core used in this embodiment maintains a constant air gap magnetic permeability along the circumference, fundamentally eliminating the magnetic circuit basis for cogging torque and achieving extremely smooth low-speed operation.

[0042] Furthermore, the slotless annular core design brings significant performance improvements. In traditional slotted structures, the coil is confined within the slot, the insulation layer at the slot opening occupies space, and the slot shape restricts the arrangement of the wires, resulting in a limited slot fill factor (the ratio of the total cross-sectional area of ​​the wires in the slot to the effective area of ​​the slot). In this embodiment, the coil winding component 220 is directly attached to the smooth core surface, unrestricted by the slot geometry, allowing for a more compact arrangement. According to actual test data, this slotless design increases the slot fill factor of the enameled wire by 10%-15% compared to the slotted structure. The increased slot fill factor means that more copper wire can be arranged on the same volume of core, allowing for a larger current and generating a stronger magnetic field. Therefore, with the same volume and current input, the frameless motor 10 of this embodiment can output a larger electromagnetic force, significantly improving the motor's torque performance and power density.

[0043] As another alternative implementation, the slotless toroidal core can be made of a soft magnetic composite material with high magnetic permeability. SMC cores, formed by powder metallurgy, exhibit isotropic magnetic properties and low eddy current losses.

[0044] Furthermore, to ensure concentricity and mechanical strength, the slotless annular core can be formed by stacking multiple annular laminations axially, or manufactured using an integrated precision machining process. Regardless of the manufacturing process, its core feature lies in maintaining the circularity and concentricity of the inner and outer diameters to ensure the uniformity of the air gap, thereby maximizing the technical advantages of the slotless structure in eliminating cogging effects and improving torque performance.

[0045] In some embodiments, the frameless motor 10 further includes a wiring assembly and a PCB board, the wiring assembly being electrically connected to the coil winding component 220 via the PCB board. Specifically, the wiring assembly refers to a wire bundle used for transmitting electrical energy and control signals, typically composed of multiple extremely fine enameled wires or flexible circuit boards, the ends of which are connected to an external drive controller. The PCB board, as a key transition component, is located at the end of the stator assembly 200 or at an axially extending mounting position, and is provided with conductive lines for signal distribution and current transmission.

[0046] This embodiment integrates and manages the cabling by introducing a PCB board as an adapter. Specifically, the PCB board establishes a stable electrical connection with the lead-out end of the coil winding component 220 through soldering or plugging. Due to the extremely small internal space of the frameless motor 10, direct soldering not only limits the operating space and easily causes poor soldering or short circuits, but also makes the solder joints prone to fatigue fracture under the vibration environment generated by the motor operation, leading to connection failure.

[0047] In comparison, using a PCB board for connection offers significant technical advantages. Firstly, in terms of space utilization, the PCB board can be customized to the end face shape of the stator structure 210 (e.g., a circular PCB), fully utilizing the unused space at the stator ends. This allows for the planarization and integration of complex wiring connections, avoiding interference from messy wires to the motor's internal air gap. Thus, an optimized electrical connection layout is achieved without increasing the motor's axial dimensions. Secondly, regarding reliability, the solder pads on the PCB board are protected by a solder mask layer, and the wiring layout is standardized, effectively preventing short circuits between wires. Furthermore, the PCB board itself can be fixed to the stator or housing with screws or adhesive, providing stress relief. When external cables are stretched, the stress is primarily borne by the PCB board, rather than directly transmitted to the fragile coil leads, significantly improving the motor's vibration resistance and lifespan.

[0048] As an alternative implementation, a temperature sensor interface or a Hall sensor interface can also be integrated on the PCB board. By pre-embedding the corresponding circuitry on the PCB board, the internal temperature of the motor or the rotor position signal can be directly monitored and transmitted to the control system via the same cabling assembly. This highly integrated electrical architecture further reduces the wiring requirements for external sensors and simplifies the overall system structure.

[0049] Furthermore, the connection methods between the cable assembly and the PCB board can be diversified. Besides common soldering connections, detachable connections such as board-to-board connectors and zero-plug-out force connectors can also be used. This design allows for quick disconnection of electrical connections during motor maintenance or replacement without disassembly and soldering, greatly improving the maintainability of the equipment. For example, during the assembly of a robot's dexterous hand, the electrical connection between the motor and the main control board can be completed simply by plugging in a connector, which not only improves assembly efficiency but also reduces the risk of thermal damage to the coil insulation layer caused by high-temperature soldering.

[0050] This application also provides a dexterous hand, which includes a dexterous hand body and a frameless motor 10 disposed on the dexterous hand body. Specifically, the dexterous hand body refers to a mechanical structure that simulates the function of a human hand, typically including a palm, multiple fingers (such as the thumb, index finger, middle finger, etc.), and joint mechanisms connecting the finger joints. The frameless motor 10, as a core driving component, is integrated at the joints of the dexterous hand body and is used to drive the bending, extending, or rotating movements of the fingers.

[0051] In this embodiment, the frameless motor 10 preferably adopts any of the aforementioned embodiments. Because dexterous hands require extremely high stability of joint movement and torque control precision when performing fine operations (such as grasping eggs, threading needles, etc.), the cogging effect generated by traditional slotted motors at low speeds can cause visible finger tremors, severely affecting the accuracy of the operation. However, this embodiment uses a frameless motor 10, utilizing its slotless structure to eliminate cogging torque, enabling the dexterous hand to maintain extreme stability during low-speed fine adjustments, resulting in finger movements as smooth and natural as a human hand.

[0052] Furthermore, the frameless motor 10 in this embodiment is specifically a micro motor with an outer diameter of 12mm. Within the compact space of the humanoid robot's hand joint, this 12mm frameless motor 10 achieves high torque density output in a very small volume through its high slot fill factor design (10%-15% higher than slotted structures). This means that the dexterous hand can directly drive the joint without complex reduction and torque amplification mechanisms, or only use a low reduction ratio transmission device, thereby simplifying the joint structure, reducing the overall weight, and improving the system's response speed and dynamic performance. Actual tests show that the dexterous hand using this frameless motor 10 has ample torque when grasping heavy objects and delicate control when handling small and light objects, fully meeting the stringent requirements of humanoid robots for high performance, high torque, and high stability.

[0053] As another alternative implementation, the frameless motor 10 can be arranged in various ways on the dexterous hand body. For example, for the thumb base joint which requires a large output torque, a frameless motor 10 with a larger diameter can be directly embedded inside the palm; while for the fingertip joints where space is limited, a frameless motor 10 with a smaller outer diameter (such as 8mm or 10mm) can be used, in conjunction with a precision lead screw transmission mechanism, to convert the rotational motion of the motor into the linear motion of the fingertip. In addition, the flattened ring structure of the frameless motor 10 is also very suitable for integration inside the knuckles of the dexterous hand, forming a compact layout of "tendon-driven" or "joint-embedded", making the dexterous hand look more biomimetic and its movements more flexible.

[0054] This application also provides a robot, which includes a robot body and a dexterous hand mounted on the robot body. Specifically, the robot body refers to the robot's torso, mobile chassis, or control center, etc., and the dexterous hand, as the robot's end effector, is mounted on the end of the robot's arm. The robot can be a bipedal humanoid robot, a wheeled service robot, or an industrial assembly robot.

[0055] This embodiment significantly enhances the robot's operational capabilities in complex environments by applying the aforementioned dexterous hand integrated with the frameless motor 10. For example, in home service scenarios, the robot needs to perform diverse tasks such as opening doors, pouring water, and tidying clothes. This requires the dexterous hand to output sufficient torque to overcome door lock resistance or the weight of a water cup, while maintaining sufficient stability to prevent liquid spillage. The dexterous hand in this embodiment, thanks to the excellent low-speed stability and high torque performance of the frameless motor 10, is perfectly suited to these tasks. Especially in scenarios where humanoid robots interact closely with humans, the low noise and low vibration characteristics of the motor greatly enhance the user's sense of security and comfort.

[0056] Furthermore, due to the simple structure and high reliability of the frameless motor 10, the risk of failure caused by brush wear or tooth groove jamming is reduced, thereby improving the overall service life of the robot and reducing maintenance costs. For industrial applications, this robot can also operate stably for extended periods in harsh environments, performing assembly or inspection of precision parts with its dexterous hand, demonstrating higher efficiency and precision than traditional servo motor drive solutions.

[0057] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this application 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, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0058] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A frameless motor, characterized in that, include: A rotor assembly includes a rotating shaft and a rotor structure, wherein the rotating shaft is disposed on the rotor structure; A stator assembly includes a stator structure and a coil winding component. The stator structure is a slotless annular structure and is arranged circumferentially around the rotor structure. The coil winding component is disposed on the stator structure.

2. The frameless motor according to claim 1, characterized in that, The stator structure has an inner ring surface and an outer ring surface arranged opposite to each other, and the coil winding component is disposed on the inner ring surface.

3. The frameless motor according to claim 2, characterized in that, The inner annular surface and the outer annular surface are coaxially arranged.

4. The frameless motor according to claim 2, characterized in that, The frameless motor also includes an adhesive component, through which the coil winding component is disposed on the inner annular surface.

5. The frameless motor according to claim 4, characterized in that, The coil winding component includes at least one coil winding, and all the coil windings are disposed on the inner annular surface of the stator structure.

6. The frameless motor according to claim 5, characterized in that, The number of coil windings is multiple, and the multiple coil windings are arranged sequentially at intervals along the circumference of the inner ring surface.

7. The frameless motor according to claim 1, characterized in that, The rotor structure is provided with a mounting through hole, which extends through the rotor structure along the axial direction, and the rotating shaft passes through the mounting through hole.

8. The frameless motor according to claim 1, characterized in that, The rotor structure is a permanent magnet rotor structure.

9. The frameless motor according to claim 1, characterized in that, The stator structure is a slotless annular iron core.

10. The frameless motor according to claim 1, characterized in that, The frameless motor also includes a wiring assembly and a PCB board, wherein the wiring assembly is electrically connected to the coil winding component through the PCB board.

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