A high rigidity SCARA robot

Abstract

The utility model discloses a high rigidity SCARA robot, including base, horizontal rotation connects on base's big arm and horizontal rotation connects on big arm's small arm, still include first axle structure, second axle structure, third axle structure and fourth axle structure, wherein, first axle structure and second axle structure all adopt the drive structure of harmonic reducer of servo motor direct connection, can guarantee high precision transmission while guaranteeing high rigidity, thereby guaranteeing big arm and small arm operation process action stable, to the accurate in -place. Third axle structure adopts ball screw, and fourth axle structure adopts spline shaft, and the screw nut of ball screw and the ball spline of spline shaft are connected through rigid connecting piece respectively, and the above -mentioned structure can guarantee the rigidity and precision of third axle structure and fourth axle structure transmission while realizing spline shaft lifting action and rotating action. Effectively improve the overall rigidity of SCARA robot in the application, and then guarantee the repeat positioning accuracy and overall machining accuracy of SCARA robot.

Description

Technical Field

[0001] This utility model relates to the field of industrial robot technology, specifically to a high-rigidity SCARA robot. Background Technology

[0002] Most conventional SCARA robots use synchronous belt drives for their third and fourth axes. This type of drive typically employs a tensioning mechanism to keep the synchronous belt taut, which also facilitates its placement within limited space. However, due to the inherent material properties of synchronous belts, they undergo elastic deformation under various application conditions. This leads to insufficient rigidity in SCARA robots using synchronous belt drives between the third and fourth axes. Particularly when the robot's end effector carries a large load, has high inertia, or moves at high speeds, the SCARA robot may experience significant deformation or vibration, severely impacting its positioning accuracy.

[0003] This shows that existing technologies still have certain shortcomings. Utility Model Content

[0004] The purpose of this invention is to provide a high-rigidity SCARA robot to solve the problems of insufficient rigidity in existing conventional SCARA robots and the resulting insufficient positioning accuracy, especially under heavy-load conditions.

[0005] To achieve the above objectives, this utility model provides a high-rigidity SCARA robot, which includes a base, a large arm horizontally rotatably connected to the base, and a forearm horizontally rotatably connected to the large arm, and further includes: A first shaft structure, which connects the base and the boom respectively, includes a first servo motor and a first harmonic reducer, for driving the boom to rotate relative to the base around a vertical axis; The second axis structure, which connects the upper arm and the lower arm respectively, includes a second servo motor and a second harmonic reducer, for driving the lower arm to rotate relative to the upper arm around a vertical axis; The third axis structure includes a third servo motor mounted on the forearm and a ball screw mounted vertically and driven by the third servo motor. The fourth axis structure includes a frameless motor, a hollow harmonic reducer, and a splined shaft mounted on the forearm. The frameless motor is driven by the hollow harmonic reducer to rotate relative to the forearm around a vertical axis. A rigid connector is provided, which is respectively engaged with the ball screw and the spline shaft. The ball screw rotates under the drive of the third servo motor and drives the rigid connector and the spline shaft to move up and down relative to the forearm in the vertical direction.

[0006] In the above scheme, both the first and second axis structures employ a drive structure where servo motors are directly connected to reducers, and both reducers in the first and second axis structures are harmonic reducers. This ensures both high rigidity and high-precision transmission. The third and fourth axis structures abandon the traditional synchronous belt drive mechanism and adopt a direct-connection drive structure. Furthermore, instead of the commonly used ball-spline composite shaft, the third and fourth axis structures use independent ball screws and ball-spline shafts for engagement. The ball screws and ball splines are independently controlled, with no coupling relationship, thus ensuring both transmission rigidity and precision. In summary, this structure significantly improves the overall rigidity of the SCARA robot, thereby guaranteeing its repeatability and overall machining accuracy.

[0007] In a preferred embodiment of this application, a support base is provided on the forearm, the third servo motor is located below the support base, one end of the ball screw passes through the support base and is driven by the third servo motor through a coupling, a limit block is provided at the upper end of the ball screw, and a buffer block is provided at the lower part of the ball screw.

[0008] In the above scheme, connecting the third servo motor to the forearm ensures the stability of the motor installation. Compared with mounting the third servo motor on the upper end of the ball screw, this avoids the third servo motor from swaying due to motion inertia when moving with the horizontal rotation of the forearm. At the same time, this arrangement can make full use of the installation space under the forearm and avoid the vertical height of the upper structure of the forearm being too high, which would affect the stability of the horizontal rotation of the forearm. The limit block at the upper end of the ball screw can prevent the screw nut from falling off the screw body beyond the travel, and the buffer block at the lower end can prevent the screw nut from mechanically colliding with the ball screw bearing nut at the lower limit position and causing damage.

[0009] In a preferred embodiment of this application, the rigid connector is provided with a spline shaft bearing, and the upper end of the spline shaft is rotatably engaged with the rigid connector through the spline shaft bearing.

[0010] This design fully utilizes the mounting space on the rigid connector, eliminating the need to occupy the mounting hole space on the upper / lower side of the rigid connector to additionally install bearing seats for the spline shaft bearing. The structure is simple and compact, which helps to further reduce the structural height of the upper part of the arm, thereby lowering the center of gravity of the entire arm structure during rotation and ensuring stability during arm rotation.

[0011] In a preferred embodiment of this application, the frameless motor includes a motor base and a motor assembly. The motor base is fixedly mounted on the forearm, and the motor assembly is installed in the motor base. In the vertical direction, the hollow harmonic reducer is installed at the lower part of the motor assembly.

[0012] Frameless motors, by eliminating the housing and independent bearings, have a more compact structure and are lighter in weight. They can output greater torque and power within the same volume, with low rotor inertia, resulting in extremely rapid start-stop, acceleration, and commutation. Positioning accuracy is exceptionally high. The hollow structure of the frameless motor, combined with a hollow harmonic reducer, allows the splined shaft to pass directly through, making the overall structure more flexible. This structure enables direct drive, eliminating transmission backlash and elastic deformation, resulting in high system rigidity and precision, while also reducing energy loss during mechanical transmission and increasing efficiency. Furthermore, the frameless motor's simple structure, lacking brushes, gears, and other easily worn parts, leads to a long service life and low maintenance requirements.

[0013] In a preferred embodiment of this application, the motor assembly includes a stator, a rotor, and a rotor shaft. The rotor shaft is provided with a rotor mounting portion, and the rotor is glued to the rotor shaft mounting portion. The rotor shaft passes through the stator and mates with the stator, and the stator and the rotor correspond radially. The hollow harmonic reducer includes a wave generator connected to the rotor shaft and a rotating housing connected to the wave generator. The rotor shaft has a hollow structure, and the splined shaft passes through the rotor shaft and the wave generator and is in a driving engagement with the rotating housing.

[0014] In a preferred embodiment of this application, the hollow harmonic reducer further includes an oil seal assembly. The oil seal assembly includes an oil seal seat disposed on the rotating housing and an oil seal disposed within the oil seal seat. A spline shaft nut assembly is also disposed on the spline shaft, and the spline shaft nut assembly is fixedly connected to the oil seal seat. By providing the oil seal assembly, lubricating oil leakage from the hollow harmonic reducer can be effectively prevented, ensuring lubrication while also preventing product or equipment structure contamination caused by lubricating oil leakage. Furthermore, integrating the spline shaft nut assembly onto the oil seal seat in the above solution makes the structure more compact, which is beneficial for miniaturizing the overall structure of the forearm.

[0015] In a preferred embodiment of this application, the inner wall of the motor base is provided with a stator mounting portion, the stator mounting portion includes a limiting step, the stator is mounted on the upper part of the limiting step and is glued and fixed to the inner wall of the motor base.

[0016] In a preferred embodiment of this application, the motor assembly further includes a first rotor shaft bearing disposed at the lower end of the rotor shaft and a second rotor shaft bearing disposed at the upper end of the rotor shaft. The lower part of the motor base is provided with a first bearing housing, and the upper part of the motor base is provided with a second bearing housing. The first rotor shaft bearing is mounted on the first bearing housing, and the second rotor shaft bearing is mounted on the second bearing housing.

[0017] In a preferred embodiment of this application, the fourth shaft structure further includes an encoder assembly disposed on the upper part of the frameless motor. The encoder assembly includes a rotor mounting base, an encoder rotor disposed on the rotor mounting base, and an encoder stator disposed corresponding to the encoder rotor. The encoder rotor is connected to the spline shaft.

[0018] In the above scheme, the mounting structure of the encoder components is simple and compact. While ensuring that the SCARA robot in this application can accurately and reliably complete various complex assembly, handling and processing operations, it is also conducive to the optimized design of the fourth axis drive structure and reduces the space occupied by the structure. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a structural schematic diagram of a high-rigidity SCARA robot in an example. Figure 2 This is a schematic diagram of the installation structure of the third and fourth axis structures in an example. Figure 3 This is a front-view sectional view of a high-rigidity SCARA robot in an example. Figure 4 for Figure 3 Enlarged view of the structure of section IV.

[0020] List of components and reference numerals: 1. Third servo motor; 2. Coupling; 3. Support base; 4. Ball screw bearing nut; 5. Buffer block; 6. Ball screw; 7. Screw nut; 8. Limit block; 9. Rigid connector; 10. Locking nut; 11. Spline shaft bearing; 12. Retaining ring; 13. Ball spline; 14. Forearm; 15. Motor base; 16. Stator; 17. Rotor; 18. Rotor shaft; 19. First rotor shaft bearing; 20. Second rotor shaft bearing; 21. Bearing housing; 22. Bearing retaining ring; 23. Rotor mounting base; 24. Encoder rotor; 25. Encoder stator; 26. Encoder cover; 27. Hollow harmonic reducer; 27-1 wave generator; 28. Spline nut seat; 29. ​​Spline nut; 30. Spline shaft; 31. Oil seal seat; 32. Oil seal. J1 is the first axis structure, J2 is the second axis structure, J3 is the third axis structure, and J4 is the fourth axis structure. Detailed Implementation

[0021] To more clearly illustrate the overall concept of this utility model, a detailed description will be provided below with reference to the accompanying drawings.

[0022] It should be noted that many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0023] like Figures 1-4 As shown, this application provides a high-rigidity SCARA robot, which includes a base, a large arm horizontally rotatably connected to the base, and a small arm 14 horizontally rotatably connected to the large arm. It also includes a first axis structure J1, a second axis structure J2, a third axis structure J3, and a fourth axis structure J4. The first axis structure J1 connects the base and the large arm, and includes a first servo motor and a first harmonic reducer, used to drive the large arm to rotate relative to the base around a vertical axis. The second axis structure J2 connects the large arm and the small arm 14, and includes a second servo motor and a second harmonic reducer, used to drive... The forearm 14 rotates relative to the upper arm around a vertical axis. A third axis structure J3 and a fourth axis structure J4 are located at the end of the forearm 14 furthest from the upper arm. The third axis structure J3 includes a third servo motor 1 mounted on the forearm 14 and a ball screw 6 arranged vertically and drivingly connected to the third servo motor 1. The fourth axis structure J4 includes a frameless motor, a hollow harmonic reducer 27, and a splined shaft 30 mounted on the forearm 14. The frameless motor drives the splined shaft 30 to rotate around a vertical axis relative to the forearm 14 via the hollow harmonic reducer 27. A rigid connector 9 is also included, which drives the ball screw 6 and the splined shaft 30 respectively. The ball screw 6 rotates under the drive of the third servo motor 1, causing the rigid connector 9 and the splined shaft 30 to move vertically relative to the forearm 14.

[0024] Preferably, both the first axis structure J1 and the second axis structure J2 adopt a drive structure where the servo motor is directly connected to the reducer, and the reducers in both the first axis structure J1 and the second axis structure J2 are harmonic reducers. This structure can ensure high rigidity while also ensuring high-precision transmission, thereby ensuring stable and precise movement of the boom and forearm 14 during operation. Meanwhile, the traditional synchronous belt drive mechanism is abandoned between the third axis structure J3 and the fourth axis structure J4 in the above scheme, and a direct connection drive structure is used instead. The commonly used ball spline 13 composite shaft is not used between the third axis structure J3 and the fourth axis structure J4; instead, an independent ball screw 6 and spline shaft 30 are used for engagement. Furthermore, the ball screw 6 and the ball spline 13 are independently controlled and there is no coupling relationship, thus ensuring the rigidity and precision of the transmission. In summary, the above structure can effectively improve the overall rigidity of the SCARA robot in this application, thereby ensuring the repeatability and overall machining accuracy of the SCARA robot.

[0025] Furthermore, referring to Figure 3 As shown, a support base 3 is provided on the forearm 14, and the third servo motor 1 is located below the support base 3. One end of the ball screw 6 passes through the support base 3 and is connected to the third servo motor 1 via a coupling 2. A limit block 8 is also provided at the upper end of the ball screw 6, and a buffer block 5 is also provided at the lower part of the ball screw 6. Connecting the third servo motor 1 to the forearm 14 ensures the stability of the motor installation. Compared with installing the third servo motor 1 at the upper end of the ball screw 6, it can avoid the third servo motor 1 from shaking due to motion inertia when moving with the horizontal rotation of the forearm 14. At the same time, this arrangement can make full use of the installation space below the forearm 14 and avoid the vertical height of the upper structure of the forearm 14 being too high, which would affect the stability of the horizontal rotation of the forearm 14. The limit block 8 at the upper end of the ball screw 6 can prevent the screw nut from falling off the screw body beyond the travel stroke, and the buffer block 5 at the lower end can prevent the screw nut from mechanically colliding with the ball screw bearing nut 4 at the lower limit position and causing damage.

[0026] In one example, continue to refer to Figure 3 As shown, the rigid connector 9 is equipped with a spline shaft bearing 11, and the upper end of the spline shaft 30 is rotatably engaged with the rigid connector 9 through the spline shaft bearing 11. This arrangement makes full use of the installation space on the rigid connector 9, eliminating the need to use the mounting holes on the upper / lower sides of the rigid connector 9 to additionally install bearing seats 21 for mounting the spline shaft bearing 11. The structure is simple and compact, which helps to further reduce the structural height of the upper part of the forearm 14, thereby lowering the center of gravity of the entire forearm 14 structure during rotation and ensuring the stability of the forearm 14 during rotation.

[0027] In actual installation, the third servo motor 1 and the support base 3 are mounted on the forearm 14. A ball screw bearing nut 4 is also installed on the upper part of the support base 3. This ball screw bearing nut 4 is mounted on the support base 3 with screws. The ball screw 6 is fixed axially and radially through the ball screw bearing nut 4 and the limiting block 8 at the upper end of the ball screw. The ball screw nut 7 is connected to the rigid connecting member 9 with screws. The spline shaft bearing 11 is fixed to the connecting member 9 by the locking nut 10 and the retaining ring 12. In actual use, the third servo motor 1 drives the ball screw 6 to rotate, causing the ball screw nut 7 to move up and down along the ball screw 6. This, in turn, drives the rigid connecting member 9 and the ball spline 13 connected to the rigid connecting member 9 to move up and down vertically, ultimately driving the spline shaft 30 connected to the ball spline 13 to move up and down, thus realizing the lifting action during the operation of the fourth axis structure.

[0028] Continue to refer to Figure 4 As shown, the frameless motor includes a motor mount 15 and a motor assembly. The motor mount 15 is fixedly mounted on the forearm 14, and the motor assembly is installed in the motor mount 15. A hollow harmonic reducer 27 is installed at the bottom of the motor assembly in the vertical direction. Because the frameless motor eliminates the outer casing and independent bearings, its structure is more compact and lighter. It can output greater torque and power within the same volume, and the rotor 17 has low inertia, resulting in very rapid start-stop, acceleration, and commutation. Its positioning accuracy is extremely high. The hollow structure of the frameless motor, combined with the hollow harmonic reducer, allows the spline shaft 30 to pass directly through, making the overall structure more flexible. This structure achieves direct drive, eliminating transmission backlash and elastic deformation, resulting in high system rigidity and precision. It also reduces energy loss during mechanical transmission, leading to higher efficiency. The structure is simple, with no brushes, gears, or other easily worn parts, resulting in a long service life and low maintenance requirements.

[0029] Continue to refer to Figure 4As shown, the motor assembly includes a stator 16, a rotor 17, and a rotor shaft 18. A rotor 17 mounting portion is provided on the rotor shaft 18, and the rotor 17 is glued to the rotor shaft 18 mounting portion. The rotor shaft 18 passes through the stator 16 and mates with the stator 16, with the stator 16 and rotor 17 corresponding radially. Preferably, a stator 16 mounting portion is provided on the inner wall of the motor housing 15. The stator 16 mounting portion includes a limiting step, and the stator 16 is mounted on the upper part of the limiting step and glued to the inner wall of the motor housing 15. The motor assembly also includes a first rotor shaft bearing 19 located at the lower end of the rotor shaft 18 and a second rotor shaft bearing 20 located at the upper end of the rotor shaft 18. A first bearing seat 21 is provided at the lower part of the motor housing 15, and a second bearing seat 21 is provided at the upper part of the motor housing 15. The first rotor shaft bearing 19 is mounted on the first bearing seat 21, and the second rotor shaft bearing 20 is mounted on the second bearing seat 21. The hollow harmonic reducer 27 includes a wave generator 27-1 connected to the rotor shaft 18 and a rotating housing connected to the wave generator 27-1. The rotor shaft 18 has a hollow structure, and a splined shaft 30 passes through the rotor shaft 18 and the wave generator 27-1 and is in drive engagement with the rotating housing. Specifically, the hollow harmonic reducer 27 also includes an oil seal 32 assembly, which includes an oil seal seat 31 on the rotating housing and an oil seal 32 in the oil seal seat 31. A splined shaft 30 nut assembly is also provided on the splined shaft 30, and the splined shaft 30 nut assembly is fixedly connected to the oil seal seat 31. By setting the oil seal 32 assembly, the lubricating oil leakage from the hollow harmonic reducer can be effectively prevented, ensuring the lubrication effect and preventing the lubricating oil leakage from causing product or equipment structure contamination. At the same time, the above solution integrates the splined shaft 30 nut assembly into the oil seal seat 31, making the structure more compact and conducive to the miniaturization of the overall structure of the boom 14.

[0030] Furthermore, the fourth axis structure J4 also includes an encoder assembly mounted on the upper part of the frameless motor. The encoder assembly includes a rotor mounting base 23, an encoder rotor 24 mounted on the rotor mounting base 23, and an encoder stator 25 corresponding to the encoder rotor 24. The encoder rotor 24 is connected to the splined shaft 30. In the above scheme, the mounting structure of the encoder assembly is simple and compact. While ensuring that the SCARA robot in this application can accurately and reliably complete various complex assembly, handling, and processing operations, it also facilitates the optimized design of the fourth axis drive structure and reduces the space occupied by the structure.

[0031] In actual assembly, firstly, the first bearing 19 of the rotor shaft is installed in the corresponding hole of the motor base 15. Secondly, the stator 16 of the frameless motor is fixed to the stator mounting part of the motor base 15 with glue, and axial positioning is achieved by the limiting step in the motor base 15. Then, the rotor 17 of the frameless motor is fixed to the rotor shaft 18 with glue. After that, the rotor 17 and the rotor shaft 18 are passed through the stator 16 of the frameless motor as a whole and installed in place, that is, the stator 16 corresponds to the rotor 17 and the lower end of the rotor shaft 18 enters the first bearing 19 of the rotor shaft. Next, the rotor shaft second bearing 20 is installed in the second bearing housing 21 on the upper part of the motor base, and the rotor shaft second bearing 20 is fixed in the second bearing housing 21 by the bearing retaining ring 22 and corresponding screws. The next step is to fix the assembly consisting of the rotor shaft second bearing 20, the second bearing housing 21, and the bearing retaining ring 22 to the motor base 15 with screws, simultaneously achieving a mating connection between the rotor shaft second bearing 20 and the upper end of the rotor shaft 18. The next step is to use the encoder rotor mounting base 23 and related screws to axially fix the upper end of the rotor shaft 18 to the rotor shaft second bearing 20. Next, the encoder rotor 24 is fixed to the encoder rotor mounting base 23 with screws, and then the encoder stator 25 is also fixed to the second bearing housing 21 with screws. Then, the encoder cover 26 is also fixed to the bearing housing 21 to provide protection for the encoder assembly and the motor assembly below it. Finally, the wave generator 27-1 of the hollow harmonic reducer is fixed to the corresponding connection part at the lower end of the rotor shaft 18 with set screws. Next, the oil seal 32 is installed in the corresponding mounting hole on the oil seal seat 31, and the oil seal 32 and the oil seal seat 31 are installed as a whole on the rotating housing of the hollow harmonic reducer 27 by screws. Then, the spline nut 29 is fixed on the spline nut seat 28, and the spline nut seat 28 is also installed on the oil seal seat 31 by screws. Finally, the fixed part of the hollow harmonic reducer 27 is fixedly installed on the forearm 14 by screws.

[0032] In application, the rotor 17 of the frameless motor rotates, driving the rotor shaft 18 to rotate. The rotation of the rotor shaft 18 in turn drives the wave generator 27-1 mounted on it to rotate. The rotation of the wave generator 27-1 drives the rotating housing of the hollow harmonic reducer 27 to rotate, which in turn drives the dynamic oil seal seat 31 on the rotating housing and the spline nut seat 28 connected to the oil seal seat 11 to rotate. The rotation of the spline nut seat 28 will drive the spline nut 29 to rotate. The rotation of the spline nut 29 will cause the spline shaft 30 fixedly connected to it to move accordingly, thus realizing the rotation action when the fourth axis structure is in operation.

[0033] The technical solutions protected by this utility model are not limited to the above embodiments. It should be noted that any combination of the technical solutions of any embodiment with one or more other embodiments is within the protection scope of this utility model. Although this utility model has been described in detail above with general descriptions and specific embodiments, some modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of this utility model are within the scope of protection claimed by this utility model.

Claims

1. A high-rigidity SCARA robot comprising a base, a large arm horizontally pivotally connected to the base, and a small arm horizontally pivotally connected to the large arm, characterized by, Also includes: The third axis structure includes a third servo motor mounted on the forearm and a ball screw mounted vertically and driven by the third servo motor. The fourth axis structure includes a frameless motor, a hollow harmonic reducer, and a splined shaft mounted on the forearm. The frameless motor is driven by the hollow harmonic reducer to rotate relative to the forearm around a vertical axis. A rigid connector is provided, which is respectively engaged with the ball screw and the spline shaft. The ball screw rotates under the drive of the third servo motor and drives the rigid connector and the spline shaft to move up and down relative to the forearm in the vertical direction.

2. The high-rigidity SCARA robot as described in claim 1, characterized in that, A support base is provided on the forearm, and the third servo motor is located below the support base. One end of the ball screw passes through the support base and is driven by the third servo motor through a coupling. A limit block is also provided at the upper end of the ball screw, and a buffer block is also provided at the lower part of the ball screw.

3. The high-rigidity SCARA robot as described in claim 1, characterized in that, The rigid connector is provided with a spline shaft bearing, and the upper end of the spline shaft is rotatably engaged with the rigid connector through the spline shaft bearing.

4. The high-rigidity SCARA robot as described in claim 1, characterized in that, The frameless motor includes a motor base and a motor assembly. The motor base is fixedly mounted on the forearm, and the motor assembly is installed in the motor base. The hollow harmonic reducer is mounted on the lower part of the motor assembly in the vertical direction.

5. The high-rigidity SCARA robot as described in claim 4, characterized in that, The motor assembly includes a stator, a rotor, and a rotor shaft. The rotor shaft has a rotor mounting portion, and the rotor is glued to the rotor shaft mounting portion. The rotor shaft passes through the stator and mates with the stator, and the stator and the rotor correspond radially. The hollow harmonic reducer includes a wave generator connected to the rotor shaft and a rotating housing connected to the wave generator. The rotor shaft has a hollow structure, and the splined shaft passes through the rotor shaft and the wave generator and is in a driving engagement with the rotating housing.

6. The high-rigidity SCARA robot as described in claim 5, characterized in that, The hollow harmonic reducer also includes an oil seal assembly, which includes an oil seal seat disposed on the rotating housing and an oil seal disposed in the oil seal seat. The spline shaft is also provided with a spline shaft nut assembly, which is fixedly connected to the oil seal seat.

7. The high-rigidity SCARA robot as described in claim 5, characterized in that, The inner wall of the motor base is provided with a stator mounting part, the stator mounting part includes a limiting step, the stator is mounted on the upper part of the limiting step and is glued and fixed to the inner side wall of the motor base.

8. The high-rigidity SCARA robot as described in claim 5, characterized in that, The motor assembly further includes a first rotor shaft bearing disposed at the lower end of the rotor shaft and a second rotor shaft bearing disposed at the upper end of the rotor shaft. The lower part of the motor base is provided with a first bearing housing, and the upper part of the motor base is provided with a second bearing housing. The first rotor shaft bearing is mounted on the first bearing housing, and the second rotor shaft bearing is mounted on the second bearing housing.

9. The high-rigidity SCARA robot as described in claim 5, characterized in that, The fourth shaft structure also includes an encoder assembly disposed on the upper part of the frameless motor. The encoder assembly includes a rotor mounting base, an encoder rotor disposed on the rotor mounting base, and an encoder stator disposed corresponding to the encoder rotor. The encoder rotor is connected to the spline shaft.

10. The high-rigidity SCARA robot as described in claim 1, characterized in that, Also includes: A first shaft structure, which connects the base and the boom respectively, includes a first servo motor and a first harmonic reducer, for driving the boom to rotate relative to the base around a vertical axis; The second axis structure, which connects the upper arm and the lower arm respectively, includes a second servo motor and a second harmonic reducer, for driving the lower arm to rotate relative to the upper arm around a vertical axis.

Images