Joint structure and robot

Abstract

The utility model discloses an embodiment provides a kind of joint structure and robot, wherein, joint structure includes: joint shell, motor and gear transmission assembly are equipped in joint shell with transmission connection;Speed reducer, speed reducer includes the wave generator assembly with gear transmission assembly transmission connection, first bearing and second bearing are sleeved on the rotating shaft of wave generator assembly, first bearing is close to joint shell and is arranged and the relative position between first bearing and rotating shaft is fixed, second bearing is away from joint shell and is arranged;Adapter flange, it is equipped in one end of speed reducer, adapter flange is equipped with assembly slot, second bearing is equipped in assembly slot;Wave spring, it is equipped in assembly slot, and wave spring is equipped in the side of second bearing away from first bearing;Wherein, the both ends of wave spring are respectively with the groove bottom of second bearing and assembly slot and resist each other.The utility model discloses technical scheme, by wave spring, can keep stable operation, reduce the uncertainty of axial and the movement unsteadiness caused by bearing play.

Description

Technical Field

[0001] This utility model relates to the field of robot joint technology, and more specifically, to a joint structure and a robot. Background Technology

[0002] Currently, the shaft of the wave generator component in a harmonic reducer is typically axially positioned using two bearings. In related technologies, wave springs are installed on the end faces of the bearings to achieve axial positioning. However, due to the shape and structure of the wave springs themselves, the compression amount cannot be accurately determined, and the state of the wave springs after being subjected to force is uncertain, resulting in unstable transmission, causing vibration and abnormal noise. Utility Model Content

[0003] The present invention aims to at least solve the technical problem of unstable transmission and abnormal noise in the existing technology or related technology of speed reducers.

[0004] In view of this, an embodiment of the present invention provides a joint structure.

[0005] Another embodiment of this utility model provides a robot.

[0006] To achieve the above objectives, embodiments of this utility model provide a joint structure, comprising: a joint housing, within which a motor and a gear transmission assembly are provided for transmission; a reducer, the reducer including a wave generator assembly for transmission with the gear transmission assembly, a first bearing and a second bearing being sleeved on the rotating shaft of the wave generator assembly, the first bearing being located close to the joint housing and the relative position between the first bearing and the rotating shaft being fixed, and the second bearing being located away from the joint housing; a transition flange located at one end of the reducer, the transition flange having an assembly groove, within which the second bearing is located; and a wave spring located within the assembly groove, the wave spring being located on the side of the second bearing away from the first bearing; wherein, the two ends of the wave spring abut against the second bearing and the bottom of the assembly groove, respectively.

[0007] According to the joint structure proposed in this utility model, by rationally arranging the first and second bearings of the wave generator assembly, and the assembly relationship between the wave spring and the transition flange, a combination of rigidity and flexibility is achieved in the axial positioning of the wave generator assembly within the reducer. This ensures the stable operation of the wave generator assembly and eliminates the motion instability problems caused by axial uncertainty and bearing clearance. Simultaneously, through a rational structural design, the wave generator assembly within the reducer achieves a tight transmission connection with the joint housing and gear transmission assembly, ensuring transmission efficiency and smoothness, reducing vibration and abnormal noise, and improving the overall performance and reliability of the joint structure.

[0008] This design achieves rigid axial positioning by fixing the first bearing near the joint housing and its relative position to the rotating shaft, ensuring the definite axial position of the wave generator assembly. A second bearing, positioned within the mounting groove of the transition flange, with a clearance fit on its outer ring and preloaded by a wave spring, provides flexible floating support, eliminating bearing clearance and ensuring smooth movement. The two ends of the wave spring abut against the second bearing and the bottom of the mounting groove, ensuring preload transmission and elastic buffering. The transition flange serves as the mounting reference for the second bearing and the support for the wave spring, ensuring overall structural stability. This design effectively solves the problems of uncertain axial positioning and instability caused by bearing clearance, improving the stability and lifespan of the harmonic reducer transmission, reducing vibration and abnormal noise, and meeting the requirements of high-performance joint structures.

[0009] In some technical solutions, the joint housing may optionally include a transmission cavity and a motor cavity, with the motor located in the motor cavity and the gear transmission assembly located in the transmission cavity; wherein, part of the rotating shaft is located in the transmission cavity and part of the rotating shaft is located outside the transmission cavity.

[0010] In this design, the joint housing is divided into a motor cavity and a transmission cavity, enabling independent addition and management of grease and avoiding insufficient lubrication or contamination caused by mixing different greases. Part of the shaft is located within the transmission cavity to ensure stable support and lubrication of the wave generator assembly and gear transmission. A portion of the shaft is located outside the transmission cavity to facilitate output connection and maintain the mechanical rigidity and assembly flexibility of the transmission system.

[0011] In some technical solutions, the joint structure may optionally include: a mounting base disposed within the joint housing, and the mounting base being connected to the inner wall of the joint housing to form a transmission cavity; wherein the motor is mounted on the mounting base.

[0012] In this technical solution, the mounting base, as an important structural component inside the joint housing, not only connects with the inner wall of the joint housing to form a complete transmission cavity, ensuring the sealing and rigidity of the cavity, but also provides a stable and precise mounting platform for the motor, ensuring good cooperation and power transmission between the motor and the transmission components, which can effectively improve the overall performance and reliability of the joint structure.

[0013] In some technical solutions, the joint housing may optionally include a connecting inner wall, the side of the connecting inner wall facing the transmission cavity being connected to the mounting base, and the side of the connecting inner wall away from the transmission cavity being provided with a first step, the first bearing abutting against the first step.

[0014] In this design, the first bearing is positioned close to the joint housing. Its inner ring is interference-fitted with the wave generator assembly shaft, while its outer ring abuts against the first step. This first step ensures the bearing's axial position is fixed, avoiding the uncertainty of axial positioning inherent in traditional wave springs. The rigid positioning of the first bearing guarantees the certainty of the wave generator assembly's axial state. Combined with the flexible wheel-side floating bearing and wave spring, this eliminates backlash, resulting in a smooth and vibration-free overall transmission system. The first step serves as an assembly datum, simplifying the assembly positioning of the first bearing, ensuring assembly quality, and facilitating subsequent maintenance and disassembly.

[0015] In some technical solutions, the transition flange is optionally connected to one end of the reducer, and the assembly groove is located on the side of the transition flange facing the joint housing.

[0016] In this technical solution, the adapter flange, as an important connecting component of the reducer, is equipped with an assembly groove on the side facing the joint housing to realize the installation and support of the second bearing and wave spring, thus ensuring the floating design and preload effect of the flexible wheel side bearing of the wave generator assembly.

[0017] In some technical solutions, optionally, the outer ring of the first bearing is interference-fitted with the joint housing, and the inner ring of the first bearing is interference-fitted with the shaft; the outer ring of the second bearing is clearance-fitted with the transition flange, and the inner ring of the second bearing is transition-fitted with the shaft.

[0018] This technical solution achieves an organic combination of rigid positioning on the rigid wheel side and floating support on the flexible wheel side of the wave generator assembly. The double interference fit of the first bearing ensures axial rigid positioning and eliminates the risk of axial movement; the floating design of the second bearing, combined with wave spring preload, effectively eliminates backlash, reduces vibration and abnormal noise, and ensures smooth transmission and bearing life.

[0019] In some technical solutions, the gear transmission assembly may optionally include: an output gear connected to the drive shaft of the motor; and a driven gear meshing with the output gear, wherein the driven gear is connected to one end of the shaft facing the joint housing to drive the shaft to rotate.

[0020] In this technical solution, the gear transmission assembly transmits power stably to the driven gear through a rigid interference fit between the output gear and the motor drive shaft. The driven gear meshes with the output gear to achieve power transfer and speed / torque adjustment. The driven gear is mechanically locked to the rotating shaft to drive it. The overall design ensures the stability of power transmission, the smoothness of transmission, and the reliability of the structure, meeting the high-precision and high-stability motion control requirements of the joint structure.

[0021] In some technical solutions, optionally, the wave generator assembly specifically includes: a wave generator, with a rotating shaft inside the wave generator; a rigid wheel and a flexible wheel that mesh with each other, the flexible wheel being sleeved outside the wave generator and the rigid wheel being sleeved outside the flexible wheel.

[0022] In this scheme, the wave generator assembly drives the wave generator to rotate via a rotating shaft. The wave generator produces waveform deformation, which drives the flexible wheel to elastically deform. The flexible wheel meshes with the tooth surface of the rigid wheel to achieve speed reduction transmission. The rotating shaft serves as the core axis, ensuring the stable rotation of the wave generator; the elastic meshing characteristics of the flexible wheel achieve high precision and high reduction ratio; and the rigid wheel serves as a rigid output ring, ensuring transmission rigidity and output efficiency.

[0023] In some technical solutions, the joint structure may optionally include a seal disposed between the first bearing and the joint housing.

[0024] In this design, the seal is located between the first bearing and the joint housing to prevent grease leakage and the intrusion of external contaminants, protect the lubrication environment and service life of the first bearing, and maintain the cleanliness and stability of the internal transmission system of the joint.

[0025] Another embodiment of the present invention provides a robot including any of the joint structures described above.

[0026] The robot in this solution includes any of the above-mentioned joint structures. The joint structure adopts a harmonic reducer, combined with rigid positioning on the rigid wheel side and floating support design on the flexible wheel side. Wave springs eliminate bearing clearance, ensuring accurate axial positioning of the wave generator assembly, improving transmission smoothness and deceleration accuracy, and meeting the robot's high requirements for motion accuracy and response speed.

[0027] This robot is suitable for industrial automation, service robots, medical robots and other fields, and is especially suitable for applications that require high precision, high reliability and long life.

[0028] It should be added that, since the robot of this solution includes the above-mentioned joint structures, it has the beneficial effects of any of the above-mentioned joint structures, which will not be elaborated here.

[0029] Additional aspects and advantages of this invention will become apparent in the description that follows, or may be learned by practice of this invention. Attached Figure Description

[0030] Figure 1 A schematic diagram of a joint structure according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of a joint structure according to an embodiment of the present invention is shown; Figure 3 A schematic diagram of a joint structure according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of a joint structure according to an embodiment of the present invention is shown.

[0031] Wherein, 1: joint structure; 11: joint housing; 111: transmission cavity; 112: motor cavity; 113: mounting base; 114: connecting inner wall; 1141: first step; 12: motor; 13: gear transmission assembly; 131: output gear; 132: driven gear; 14: reducer; 141: wave generator assembly; 1411: rotating shaft; 1412: wave generator; 1413: rigid wheel; 1414: flexible wheel; 151: first bearing; 152: second bearing; 16: adapter flange; 161: assembly groove; 17: wave spring; 18: seal. Detailed Implementation

[0032] To better understand the above-mentioned objectives, features, and advantages of the embodiments of this utility model, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0033] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, embodiments of the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0034] In related technologies, the two bearings on the hollow shaft of the wave generator assembly in a harmonic reducer are axially positioned by wave springs (hereinafter referred to as "wave springs"). Due to the large tolerances of the wave springs themselves, the compression amount cannot be accurately determined, resulting in uncertain axial force; the state of the wave spring under stress is also uncertain, leading to uncertain state of the wave generator assembly; all of these factors can cause unstable transmission, resulting in vibration and abnormal noise. Furthermore, since the harmonic reducer and driven gear are in the same cavity, the amount of grease added cannot adequately lubricate the gears.

[0035] The following reference Figures 1 to 4 Some embodiments of the present invention are described below.

[0036] like Figure 1 , Figure 2 and Figure 3As shown, this embodiment provides a joint structure 1. By rationally arranging the first bearing 151 and the second bearing 152 of the wave generator assembly 141, and the assembly relationship between the wave spring 17 and the transition flange 16, a combination of rigidity and flexibility is achieved in the axial positioning of the wave generator assembly 141 within the reducer 14. This ensures the stable operation of the wave generator assembly 141 and eliminates the motion instability problems caused by axial uncertainty and bearing clearance. Simultaneously, through a rational structural design, the wave generator assembly 141 within the reducer 14 achieves a tight transmission connection with the joint housing 11 and the gear transmission assembly 13, ensuring transmission efficiency and smoothness, reducing vibration and abnormal noise, and improving the overall performance and reliability of the joint structure 1.

[0037] Specifically, the joint structure 1 includes a joint housing 11, a reducer 14, an adapter flange 16, and a wave spring 17. The joint housing 11 serves as the outer shell of the entire joint structure 1, internally housing the motor 12 and the gear transmission assembly 13. The reducer 14 and the wave generator assembly 141 are also installed within the joint housing 11, providing rigid support and protection for the overall mechanical structure, ensuring the relative fixation and alignment of the internal components, and preventing interference and damage to the internal transmission system from the external environment. Simultaneously, the joint housing 11 ensures a stable transmission connection between the motor 12 and the gear transmission assembly 13, and provides an installation reference for the reducer 14.

[0038] The motor 12 is installed inside the joint housing 11 and is tightly fitted with the gear transmission assembly 13. The gear transmission assembly 13 is connected to the wave generator assembly 141 of the reducer 14. The motor 12 serves as a power source and transmits power to the wave generator assembly 141 of the reducer 14 through the gear transmission assembly 13, thereby achieving effective torque transmission and speed regulation, and ensuring the motion accuracy and stability of the joint output.

[0039] The reducer 14 is installed inside the joint housing 11 and is connected to the gear transmission assembly 13. It contains a wave generator assembly 141. The reducer 14 achieves high-precision, high-reduction-ratio transmission through the wave generator assembly 141, meeting the torque amplification and motion control requirements of the joint structure 1. The design of the reducer 14 ensures smooth and efficient transmission. The wave generator assembly 141 is installed inside the reducer 14. A first bearing 151 and a second bearing 152 are mounted on the rotating shaft 1411. As the core transmission element of the harmonic reducer 14, the wave generator assembly 141 converts the high-speed rotation output from the motor 12 into a low-speed, high-torque output. The support of the first bearing 151 and the second bearing 152 ensures the stable positioning of the wave generator assembly 141 in the radial and axial directions, guaranteeing the accuracy and reliability of the transmission.

[0040] The first bearing 151 is located close to the joint housing 11, and the relative position between the first bearing 151 and the rotating shaft 1411 is fixed. The first bearing 151 and the rotating shaft 1411 are rigidly positioned, specifically at this end of the rotating shaft 1411 of the wave generator assembly 141, to prevent axial movement, ensure the relative position between the rotating shaft 1411 and the housing is stable, and eliminate the unstable movement caused by the uncertain axial positioning of the wave spring 17.

[0041] The second bearing 152 is located away from the joint housing 11 and in the assembly groove 161 within the transition flange 16. The wave spring 17 allows the outer ring of the bearing to float axially within the assembly groove 161, eliminating bearing clearance caused by manufacturing tolerances and thermal expansion. Through the floating design, the increase in bearing internal stress caused by rigid constraints is avoided, thereby improving bearing life and operational stability. Of course, the second bearing 152, as a flexible support end, provides the necessary radial load for the wave generator assembly 141, while eliminating the instability of movement caused by excessive axial tightness.

[0042] An adapter flange 16 is located at one end of the reducer 14 and has an internal mounting groove 161. The second bearing 152 and a wave spring 17 are installed within the mounting groove 161. The adapter flange 16 is connected to the reducer 14 housing and serves as a support structure for the outer ring of the second bearing 152. The bottom of the mounting groove 161 serves as a support surface for one end of the wave spring 17. The adapter flange 16 acts as the mounting reference for the second bearing 152, ensuring the radial positioning of the bearing's outer ring. The adapter flange 16 provides a fixed base for the wave spring 17 through the mounting groove 161, enabling effective preload transmission of the spring.

[0043] The reducer 14 is connected to other parts of the joint structure 1 to achieve the rigidity and stability of the overall structure.

[0044] The assembly groove 161 is located inside the transition flange 16 and is used to install the second bearing 152 and the wave spring 17. The assembly groove 161 provides radial positioning space for the outer ring of the second bearing 152, allowing it to float axially and eliminating motion instability caused by clearance. At the same time, the assembly groove 161 provides a stable support point for the wave spring 17, ensuring that the spring can effectively apply preload.

[0045] The wave spring 17 is located in the assembly groove 161, on the side of the second bearing 152 away from the first bearing 151. One end of the wave spring 17 is in direct contact with the end face of the second bearing 152, and the other end is in close contact with the bottom surface of the assembly groove 161.

[0046] The spring force eliminates the axial clearance between the second bearing 152 and the mounting groove 161, providing a slight preload to avoid impact and movement between the bearing end faces. The elastic buffering effect of the spring helps absorb errors caused by manufacturing and assembly tolerances, prevents hard collisions between parts, and extends the life of bearings and components.

[0047] It is understandable that the spring does not perform the axial positioning function, thus avoiding the problems caused by the uncertain positioning compression of traditional wave springs.

[0048] Optionally, the outer ring of the second bearing 152 is clearance-fitted, and the presence of the wave spring 17 ensures that the bearing will not generate negative clearance, thereby improving the smoothness of the movement of the wave generator assembly 141.

[0049] Overall, this design achieves rigid axial positioning by fixing the relative position of the first bearing 151 near the joint housing 11 and the rotating shaft 1411, ensuring the definite axial position of the wave generator assembly 141. A second bearing 152, positioned within the mounting groove 161 of the transition flange 16, with a clearance fit on its outer ring and preloaded by a wave spring 17, provides flexible floating support, eliminating bearing clearance and ensuring smooth movement. The two ends of the wave spring 17 abut against the second bearing 152 and the bottom of the mounting groove 161, respectively, ensuring preload transmission and elastic buffering. The transition flange 16 serves as the mounting reference for the second bearing 152 and the support for the wave spring 17, ensuring overall structural stability. This design effectively solves the problems of uncertain axial positioning and instability caused by bearing clearance, improving the stability and lifespan of the harmonic reducer 14, reducing vibration and abnormal noise, and meeting the requirements of the high-performance joint structure 1.

[0050] In some embodiments, the joint housing 11 is optionally divided into two relatively independent cavities: a motor cavity 112 housing a motor 12 for providing power, and a transmission cavity 111 housing a gear transmission assembly 13 for transmitting and reducing power.

[0051] The motor cavity 112 and the transmission cavity 111 are physically separated by a shell structure to prevent the mixing of lubricating grease and reduce lubrication contamination. The output end of the drive shaft passes through the interface between the motor cavity 112 and the transmission cavity 111. Part of the rotating shaft 1411 is located inside the transmission cavity 111, and part of the rotating shaft 1411 is located outside the transmission cavity 111, forming a power transmission link.

[0052] The motor cavity 112 is located on one side of the housing and the motor body is fixed inside. The transmission cavity 111 is located on the other side of the housing, adjacent to the motor cavity 112 but sealed and isolated. The rotating shaft 1411 partially passes through the boundary between the two cavities, partially is located in the transmission cavity 111 to participate in gear transmission, and partially is located outside the transmission cavity 111 to connect to other mechanisms or the output end.

[0053] The motor cavity 112 serves as the installation space for the motor 12, providing good mechanical support and heat dissipation environment. The independent motor cavity 112 prevents the motor grease from mixing with the gear grease, ensuring the cleanliness of the motor 12's operating environment and the stability of the grease's performance.

[0054] Optionally, the drive shaft is connected to the transmission cavity 111 through a sealing structure to ensure power transmission while preventing grease leakage. The drive shaft and the gear transmission assembly 13 are connected through bearings and a sealing structure to ensure smooth power transmission. A sealing structure is provided between the housing wall of the motor cavity 112 and the housing wall of the transmission cavity 111 to prevent grease from flowing between the cavities.

[0055] The transmission cavity 111 serves as the installation space for the gear transmission assembly 13, ensuring a proper lubrication environment for the gears and the wave generator assembly of the reducer. The independent transmission cavity allows for the separate, quantitative addition of grease according to the lubrication requirements of the gear transmission, ensuring sufficient lubrication for gear meshing and preventing insufficient gear lubrication due to grease limitations in the reducer 14. The rotating shaft 1411 within the transmission cavity 111 is supported by bearings, enabling power transmission between the gears and the wave generator assembly 141. The transmission cavity 111 and the motor cavity 112 are isolated by a non-contact sealing structure, ensuring independent grease supply between the two cavities.

[0056] The rotating shaft 1411, located within the transmission cavity 111, primarily supports and transmits power to the wave generator assembly of the gear transmission and reducer. It is fixed to the transmission cavity housing by bearings, maintaining the radial and axial positioning of the rotating shaft 1411. The bearing support, combined with the preload of the wave spring 17, ensures smooth operation of the rotating shaft 1411, preventing vibration and abnormal noise. Because it is located within the transmission cavity 111, the rotating shaft 1411 and its bearings enjoy an independent lubrication environment within the transmission cavity 111, ensuring effective lubrication.

[0057] The rotating shaft 1411 located outside the transmission cavity 111 is either an output shaft or a shaft connecting to an external mechanical structure. Its location outside the transmission cavity 111 facilitates mechanical connection to an external load and simplifies the assembly and maintenance of the output end. The rotating shaft 1411 outside the transmission cavity 111 is sealed to the transmission cavity 111 by a sealing structure to prevent grease leakage.

[0058] The rotating shaft 1411 inside the transmission cavity 111 is connected to the rotating shaft 1411 outside the transmission cavity 111 through a shoulder or end cover to ensure continuous power transmission. The rotating shaft 1411 outside the transmission cavity 111 is closely matched with the external mechanical structure of the joint to complete the motion output.

[0059] In summary, by dividing the joint housing 11 into a motor cavity 112 and a transmission cavity 111, independent addition and management of grease are achieved, avoiding insufficient lubrication or contamination problems caused by mixing different greases. A portion of the rotating shaft 1411 is disposed within the transmission cavity 111 to ensure stable support and lubrication of the wave generator assembly 141 and the gear transmission. A portion of the rotating shaft 1411 is disposed outside the transmission cavity 111 to facilitate output connection and maintain the mechanical rigidity and assembly flexibility of the transmission system.

[0060] In some embodiments, the mounting base 113 is optionally disposed inside the joint housing 11, and the mounting base 113 is connected to the inner wall of the joint housing 11. Together, they form the boundary of the transmission cavity 111. The motor 12 is mounted on the mounting base 113, and the mounting base 113 serves as the support base for the motor 12.

[0061] Mounting base 113 is securely connected to the inner wall of joint housing 11 via mechanical connections such as bolts, riveting, press fitting, or welding. The connection between mounting base 113 and the inner wall of joint housing 11 forms a complete transmission cavity, ensuring the sealing and rigidity of the transmission cavity 111. Motor 12 is fixed by mounting base 113, ensuring the accurate and stable position of motor 12.

[0062] Mounting base 113 connects to the inner wall of joint housing 11 to form transmission cavity 111, providing a clear cavity division. This ensures the transmission cavity 111 has a complete structure and good sealing, effectively isolating the motor cavity 112 and the transmission cavity 111 from lubricating grease. Mounting base 113 serves as a mechanical mounting platform for motor 12, ensuring the installation accuracy and rigidity of motor 12, reducing motor 12 vibration, and ensuring the coaxiality of the drive shaft and gear transmission assembly 13 and the stability of power transmission. Through the connection between mounting base 113 and the housing, vibrations generated by motor 12 can be isolated and buffered to a certain extent, improving the overall noise reduction performance of the joint.

[0063] Mounting bracket 113 facilitates the assembly and disassembly of motor 12, makes maintenance and replacement convenient, and ensures a reasonable spatial layout between motor 12 and other components of transmission cavity 111.

[0064] Optionally, the mounting base 113 can be designed as a heat dissipation structure, such as having heat dissipation ribs or heat conduction material, to assist the heat conduction of the motor 12 to the joint housing 11, which is beneficial to the thermal management of the motor 12.

[0065] In general, the inner wall of the joint housing 11 and the mounting base 113 together form the complete boundary of the transmission cavity 111, ensuring the transmission cavity 111 is sealed, preventing grease leakage and contamination, and providing suitable installation space and lubrication environment for the gear transmission assembly 13 and part of the rotating shaft 1411 in the transmission cavity 111.

[0066] The motor 12 is fixed by the mounting base 113, which ensures a stable position and makes the output end of the drive shaft coaxial with the axis of the gear transmission assembly 13, reducing transmission errors. The rigidity and precision of the mounting base 113 directly affect the vibration and noise level of the motor 12. A well-designed mounting base 113 can effectively reduce the vibration and noise of the overall joint.

[0067] Mounting base 113 is located inside joint housing 11, physically isolating motor 12 from transmission cavity 111. Motor cavity 112 is independent of transmission cavity 111, which facilitates zoned management of grease and heat dissipation.

[0068] Optionally, the mounting base 113 is made of high-strength aluminum alloy or steel, which balances rigidity and lightweight. The mechanical connection should be secure and free from loosening. It is recommended to use fastening bolts and locating pins to ensure assembly positioning accuracy.

[0069] Optionally, a sealing ring or sealant should be designed at the connection between the mounting base 113 and the housing to ensure the airtightness of the transmission cavity 111 and the motor cavity 112.

[0070] Optionally, the mounting base 113 may be designed with a heat sink structure to improve the heat dissipation efficiency of the motor 12.

[0071] Optionally, a rubber pad or elastic washer may be provided between the mounting base 113 and the motor 12 to further reduce vibration transmission.

[0072] In this design, the mounting base 113, as an important structural component inside the joint housing 11, not only connects with the inner wall of the joint housing 11 to form a complete transmission cavity 111, ensuring the sealing and rigidity of the cavity, but also provides a stable and precise mounting platform for the motor 12, ensuring good cooperation and power transmission between the motor 12 and the transmission components, which can effectively improve the overall performance and reliability of the joint structure 1.

[0073] In some embodiments, the connecting inner wall 114 is optionally a structural surface or component inside the joint housing 11, located between the transmission cavity 111 and the mounting base 113.

[0074] The inner wall 114 is connected to the mounting base 113 on the side facing the transmission cavity 111, forming the boundary part of the transmission cavity 111. The inner wall 114 away from the transmission cavity 111 is provided with a first step 1141. The inner wall 114 is mechanically connected to the mounting base 113 to ensure the structural integrity and rigidity of the transmission cavity 111. The first step 1141 serves as the axial support surface of the first bearing 151, and the first bearing 151 abuts against the step.

[0075] The connecting inner wall 114 serves as the connection structure between the transmission cavity 111 and the mounting base 113, enhancing the overall rigidity and stability of the housing and ensuring the dimensional stability of the transmission cavity 111. The first step 1141 provides a clear axial positioning surface for the first bearing 151, ensuring accurate radial and axial positioning of the first bearing 151 and preventing axial movement of the bearing. By connecting the inner wall 114 and the first step 1141, the force transmission path of the bearing is clear, ensuring uniform load distribution and reducing local stress concentration.

[0076] The presence of the first step 1141 provides a direct contact surface for the first bearing 151, simplifying the bearing assembly steps and positioning, and improving assembly accuracy and efficiency.

[0077] It is understood that the connecting inner wall 114 serves as a load-bearing structure inside the joint housing 11, and is connected to the mounting base 113 to form the transmission cavity 111, ensuring the size and rigidity of the transmission cavity 111; the first step 1141 serves as a structural extension of the connecting inner wall 114, providing a reliable axial positioning end face for the first bearing 151.

[0078] The first bearing 151 is located near the joint housing 11. Its inner ring is interference-fitted with the rotating shaft 1411 of the wave generator assembly 141, and its outer ring abuts against the first step 1141. The first step 1141 ensures that the axial position of the bearing is fixed, avoiding the uncertainty of the axial positioning of the traditional wave spring 17. The rigid positioning of the first bearing 151 ensures the certainty of the axial state of the wave generator assembly 141. Together with the floating bearing on the side of the flexible wheel 1414 and the wave spring 17, it eliminates backlash and achieves a smooth and vibration-free overall transmission system. The first step 1141 serves as an assembly datum, simplifying the assembly positioning of the first bearing 151, ensuring assembly quality, and facilitating subsequent maintenance and disassembly.

[0079] In some embodiments, the transition flange 16 is optionally installed at one end of the reducer 14. An assembly groove 161 is provided on the side of the transition flange 16 facing the joint housing 11; that is, the side of the transition flange 16 facing the joint housing 11 has an assembly groove 161 structure. The transition flange 16 is mechanically connected to the end of the reducer 14 via bolts, interference fits, etc., forming an integral structure. The assembly groove 161, as a recessed structure inside the transition flange 16, is used to install components such as the second bearing 152 and the wave spring 17.

[0080] The transition flange 16 serves as an intermediate connecting component between the reducer 14 and the joint housing 11, undertaking mechanical connection and positioning functions. The assembly groove 161 is located on the side of the transition flange 16 facing the joint housing 11, ensuring the correct installation position of the second bearing 152 and the wave spring 17, and ensuring the effectiveness of the floating support structure on the flexible wheel 1414 side of the reducer's wave generator assembly. The structure of the assembly groove 161, combined with the clearance fit of the second bearing 152 and the elastic preload design of the wave spring 17, effectively eliminates bearing clearance, avoiding unstable movement and abnormal vibration and noise.

[0081] In summary, the adapter flange 16, as an important connecting component of the reducer 14, achieves the installation and support of the second bearing 152 and the wave spring 17 by setting the assembly groove 161 on the side facing the joint housing 11, thus ensuring the floating design and preload effect of the bearing on the flexible wheel 1414 side of the wave generator assembly 141.

[0082] In some embodiments, optionally, the outer ring of the first bearing 151 is interference-fitted with the joint housing 11, and the outer ring is tightly pressed into the corresponding bearing seat hole of the joint housing 11 through the interference fit, ensuring that the radial and axial positions of the outer ring are fixed. The inner ring of the first bearing 151 is interference-fitted with the rotating shaft 1411, and is mounted on the rotating shaft 1411 of the wave generator assembly 141 through the interference fit, thereby achieving radial and axial fixation of the inner ring.

[0083] For the first step 1141, the outer ring is interference-fitted with the joint housing 11 to ensure that the outer ring of the first bearing 151 cannot move radially or axially, providing rigid fixed support. Combined with the end face positioning of the first step 1141, the axial position of the first bearing 151 is rigidly restricted, eliminating axial backlash and ensuring accurate axial positioning of the shaft 1411 of the wave generator assembly 141. The interference fit ensures that the inner and outer rings are tightly connected with their corresponding parts, enhancing the bearing's load-bearing rigidity and resisting radial loads and vibrations. Through the double interference fit, the first bearing 151 becomes a rigid support point on the side of the rigid wheel 1413 of the wave generator assembly 141, ensuring stable movement during transmission and reducing vibration and abnormal noise.

[0084] For the second bearing 152, the outer ring of the second bearing 152 has a clearance fit with the transition flange 16, and an appropriate clearance is left with the mounting groove 161 of the transition flange 16, allowing the outer ring to be fixed radially while allowing for slight axial movement. The inner ring of the second bearing 152 has an transition fit with the shaft 1411, that is, between interference and clearance, ensuring that the inner ring is firmly installed but allowing for slight adjustment. The clearance fit of the outer ring allows the outer ring of the second bearing 152 to move slightly axially within the mounting groove 161 of the transition flange 16, eliminating axial stress caused by manufacturing tolerances, thermal expansion, etc., and preventing bearing movement and excessive tightness.

[0085] A slight preload is applied to the outer ring end face of the second bearing 152 by the wave spring 17, eliminating bearing clearance and improving motion smoothness. The inner ring transition fit ensures a tight fit between the bearing inner ring and the shaft 1411 with a certain degree of elastic cushioning, preventing deformation or damage to the inner ring due to excessive tightness. The floating design reduces internal bearing stress, minimizes abnormal wear of the rolling elements and cage, and extends bearing life. The transition fit inner ring facilitates bearing positioning and adjustment on the shaft, and, combined with the floating outer ring, simplifies the assembly process.

[0086] In summary, this solution achieves an organic combination of rigid positioning on the rigid wheel 1413 side and floating support on the flexible wheel 1414 side of the wave generator assembly 141. The double interference fit of the first bearing 151 ensures axial rigid positioning and eliminates the risk of axial movement; the floating design of the second bearing 152, combined with the preload of the wave spring 17, effectively eliminates backlash, reduces vibration and abnormal noise, and ensures smooth transmission and bearing life.

[0087] In some embodiments, the gear transmission assembly 13 may optionally include an output gear 131 and a driven gear 132, wherein the output gear 131 is mounted on the drive shaft of the motor 12 and may optionally be fixed by an interference fit, and the output gear 131 serves as the driving gear for power transmission, directly receiving torque from the drive shaft.

[0088] Driven gear 132 meshes with output gear 131 to transmit power. Driven gear 132 is mounted on the end of rotating shaft 1411 facing joint housing 11 and is rigidly connected to rotating shaft 1411 by a fixing structure, such as screws. As the driven gear of the transmission system, driven gear 132 transmits power to rotating shaft 1411, driving rotating shaft 1411 to rotate.

[0089] Optionally, the output gear 131 is fastened to the drive shaft of the motor 12 by an interference fit, ensuring that there is no relative slippage between the gear and the shaft, realizing efficient torque transmission. The interference fit improves the connection strength, prevents the gear from loosening during operation, ensures the reliability of the transmission system, and ensures that the power is stably transmitted from the drive shaft to the output gear 131, ensuring that the output torque of the motor 12 is not lost.

[0090] The output gear 131 meshes with the driven gear 132, transmitting power to the driven gear 132 to achieve speed and torque conversion. The gear meshing ensures the continuity and smoothness of power transmission. Through gear meshing, power is effectively transmitted from the motor 12 to the next stage of the transmission system, meeting the needs of deceleration or acceleration.

[0091] The driven gear 132 is fixed to the end face of the rotating shaft 1411 by mechanical fastening methods such as screws, ensuring that the driven gear 132 and the rotating shaft 1411 are coaxial and rigidly connected. The driven gear 132 drives the rotating shaft 1411 to rotate, realizing power output. The mechanical fastening ensures that the driven gear 132 does not slip or loosen, improving the overall stability of the transmission system. The rigid connection between the driven gear 132 and the rotating shaft 1411 ensures the accuracy and response speed of the rotating shaft 1411's rotation, meeting the requirements of high-precision motion control.

[0092] The gear transmission assembly 13, through a rigid interference connection between the output gear 131 and the drive shaft of the motor 12, stably transmits power to the driven gear 132. The driven gear 132 meshes with the output gear 131 to achieve power transfer and speed / torque adjustment. The driven gear 132 is mechanically locked to the rotating shaft 1411, thereby driving the rotating shaft 1411. The overall design ensures the stability of power transmission, the smoothness of transmission, and the reliability of the structure, meeting the high-precision and high-stability motion control requirements of the joint structure 1.

[0093] In some embodiments, the wave generator assembly 141 may optionally include a wave generator 1412, a rotating shaft 1411, a rigid wheel 1413, and a flexible wheel 1414. The rotating shaft 1411 is provided inside the wave generator 1412 as the main shaft of the wave generator assembly 141. Optionally, the structure of the wave generator 1412 includes an elliptical wave roller or wave collar for driving the flexible wheel 1414 to deform.

[0094] The flexible gear 1414, as a flexible gear ring sleeved outside the wave generator 1412, has a certain elasticity and can generate tooth meshing with the waveform deformation of the wave generator 1412. The rigid gear 1413, as a rigid gear ring sleeved outside the flexible gear 1414, meshes with the tooth surface of the flexible gear to form the transmission chain of the harmonic reducer 14.

[0095] The rotating shaft 1411 serves as the rotation axis of the wave generator 1412, bearing the torque and ensuring the rotational accuracy of the wave generator 1412. The rotating shaft 1411 is supported by bearings to ensure the radial and axial stability of the wave generator 1412, ensuring the stability and accuracy of the wave generator 1412 during rotation and reducing vibration and sway.

[0096] The elliptical waveform of the wave generator 1412 drives the flexible wheel 1414 to deform, causing the flexible wheel teeth to elastically deform along the waveform. Through the waveform deformation, the periodic meshing of the flexible wheel teeth and the rigid wheel teeth is achieved, generating the core reduction principle of the harmonic reducer 14, realizing a high reduction ratio and high transmission accuracy. The elastic deformation of the flexible wheel 1414 ensures good contact of the meshing tooth surfaces, reducing impact and noise.

[0097] The rigid wheel 1413, as a rigid gear ring, meshes with the flexible wheel 1414 to form a reduction gear chain. The rigid wheel 1413 is sleeved on the outside of the flexible wheel 1414 to ensure a compact structure and rigid output. Torque transmission and speed reduction are achieved through the meshing of the rigid wheel 1413 and the flexible wheel 1414. The rigid wheel 1413 provides a rigid output end to ensure stable power output and transmission efficiency.

[0098] In summary, the wave generator assembly 141 drives the wave generator 1412 to rotate via the rotating shaft 1411. The wave generator 1412 produces waveform deformation, which drives the flexible wheel 1414 to elastically deform. The flexible wheel 1414 meshes with the tooth surface of the rigid wheel to achieve speed reduction transmission. The rotating shaft 1411 serves as the core shaft, ensuring the stable rotation of the wave generator 1412; the elastic meshing characteristics of the flexible wheel 1414 achieve high precision and high reduction ratio; and the rigid wheel 1413 serves as a rigid output ring, ensuring transmission rigidity and output efficiency.

[0099] In some embodiments, optionally, such as Figure 4As shown, the seal 18 is installed in the gap between the first bearing 151 and the joint housing 11, located in the sealing area between the outer ring of the first bearing 151 and the bearing seat hole of the joint housing 11. The seal 18 is arranged around the rotation axis of the first bearing 151 to form an effective sealing interface.

[0100] One side of the seal 18 is tightly fitted with the outer ring of the first bearing 151, and the other side is in sealing contact with the inner wall of the joint housing 11, such as the bearing seat hole. The seal 18 is fixed and sealed by elastic compression or interference fit.

[0101] The seal 18 effectively prevents the internal grease of the first bearing 151 from leaking outward, ensuring that the grease remains sufficient and uncontaminated in the bearing for a long time, preventing external dust, moisture and impurities from entering the first bearing 151, and reducing the risk of bearing wear and corrosion.

[0102] In general, the seal 18 is located between the first bearing 151 and the joint housing 11 to prevent grease leakage and the intrusion of external contaminants, protect the lubrication environment and service life of the first bearing 151, and maintain the cleanliness and stability of the internal transmission system of the joint.

[0103] Another embodiment of this application provides a robot including any of the above-described joint structures 1. The joint structure 1 adopts a harmonic reducer 14, which combines rigid positioning on the side of the rigid wheel 1413 with floating support design on the side of the flexible wheel 1414. The wave spring 17 eliminates bearing clearance, ensuring accurate axial positioning of the wave generator assembly 141, improving transmission smoothness and deceleration accuracy, and meeting the robot's high requirements for motion accuracy and response speed.

[0104] This robot is suitable for industrial automation, service robots, medical robots and other fields, and is especially suitable for applications that require high precision, high reliability and long life.

[0105] It should be added that, since the robot of this solution includes the above-mentioned joint structure 1, it has the beneficial effects of any of the above-mentioned joint structures 1, which will not be elaborated here.

[0106] This application also provides a specific embodiment of a collaborative arm joint, wherein the outer ring of the rigid wheel-side bearing (i.e., the first bearing) on ​​the shaft (i.e., the rotating shaft) of the wave generator assembly is interference-fitted with the rotating seat (i.e., the joint housing), and the inner ring is interference-fitted with the shaft of the wave generator assembly. This fixes and positions the wave generator assembly axially, ensuring its correct and normal state. This eliminates instability caused by a lack of axial positioning of the wave generator assembly and wobble caused by radial clearance.

[0107] The outer ring of the flexible wheel side bearing (i.e., the second bearing) on ​​the shaft of the wave generator assembly is installed with a clearance to the transition flange, and the inner ring is transitionally fitted to the shaft of the wave generator assembly. Additionally, a wave spring is added between the bearing end face and the transition flange to eliminate bearing clearance and thus eliminate the instability caused by bearing clearance.

[0108] The structure of the rigid wheel side bearing of the reducer wave generator assembly is interference-fitted, while the flexible wheel side floating bearing plus wave spring eliminates the uncertainty caused by axial positioning by wave spring, and solves the problem of unstable movement and sway caused by bearing clearance.

[0109] By using a non-contact sealed bearing on the gearbox side, the reducer and gear drive are separated into two chambers. The reducer is lubricated according to the standard amount, while the gear chamber is lubricated according to the amount required for the gear drive. This avoids the problem of insufficient gear lubrication caused by limitations in the reducer's lubrication capacity.

[0110] The outer ring of the first bearing (i.e., the first bearing) on ​​the rigid wheel side of the wave generator assembly shaft of the reducer is interference-fitted with the sprocket (i.e., the joint housing), and the inner ring of the bearing is interference-fitted with the wave generator assembly shaft; the outer ring of the second bearing (i.e., the second bearing) on ​​the flexible wheel side of the wave generator assembly shaft of the reducer is clearance-fitted with the transition flange, and the inner ring is transition-fitted with the shaft of the wave generator assembly, providing auxiliary support. The axial movement of the outer ring is possible. A wave spring is installed between the end face of the second bearing and the stepped hole (i.e., the mounting groove) of the transition flange; the driven gear is installed on the end face of the wave generator assembly shaft of the reducer and locked with screws; the output gear is installed on the drive shaft and needs to be interference-fitted with the drive shaft.

[0111] In this utility model, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "join," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "join" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0112] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0113] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0114] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A joint structure, characterized in that, include: A joint housing, wherein a motor and a gear transmission assembly are provided for transmission connection within the joint housing; The speed reducer includes a wave generator assembly that is connected to the gear transmission assembly. A first bearing and a second bearing are sleeved on the rotating shaft of the wave generator assembly. The first bearing is located close to the joint housing and the relative position between the first bearing and the rotating shaft is fixed. The second bearing is located away from the joint housing. An adapter flange is provided at one end of the reducer, and the adapter flange is provided with an assembly groove, in which the second bearing is provided; A wave spring is disposed in the assembly groove, and the wave spring is disposed on the side of the second bearing away from the first bearing; The two ends of the wave spring abut against the bottom of the second bearing and the assembly groove, respectively.

2. The joint structure according to claim 1, characterized in that, The joint housing includes a transmission cavity and a motor cavity, the motor is disposed in the motor cavity, and the gear transmission assembly is disposed in the transmission cavity; Some of the rotating shafts are located inside the transmission cavity, while others are located outside the transmission cavity.

3. The joint structure according to claim 2, characterized in that, Also includes: A mounting base is disposed within the joint housing, and the mounting base is connected to the inner wall of the joint housing to form the transmission cavity; The motor is mounted on the mounting base.

4. The joint structure according to claim 3, characterized in that, The joint housing includes a connecting inner wall, the side of which facing the transmission cavity is connected to the mounting base, and the side of which away from the transmission cavity is provided with a first step, the first bearing abutting against the first step.

5. The joint structure according to claim 1, characterized in that, The adapter flange is connected to one end of the reducer, and the assembly groove is located on the side of the adapter flange facing the joint housing.

6. The joint structure according to claim 1, characterized in that, The outer ring of the first bearing is interference-fitted with the joint housing, and the inner ring of the first bearing is interference-fitted with the shaft. The outer ring of the second bearing is clearance-fitted with the transition flange, and the inner ring of the second bearing is transition-fitted with the shaft.

7. The joint structure according to claim 1, characterized in that, The gear transmission assembly includes: The output gear is connected to the drive shaft of the motor; The driven gear meshes with the output gear, and the driven gear is connected to the end of the rotating shaft facing the joint housing, so as to drive the rotating shaft to rotate.

8. The joint structure according to claim 1, characterized in that, The wave generator assembly specifically includes: A wave generator, wherein the rotating shaft is provided inside the wave generator; A rigid wheel and a flexible wheel mesh with each other, wherein the flexible wheel is sleeved outside the wave generator and the rigid wheel is sleeved outside the flexible wheel.

9. The joint structure according to claim 1, characterized in that, Also includes: A seal is provided between the first bearing and the joint housing.

10. A robot, characterized in that, include: The joint structure as described in any one of claims 1 to 9.

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