Single-shaft high-precision servo electric actuator

Abstract

The utility model provides a single-shaft high-precision servo electric actuator which comprises a first servo motor, a lead screw connected with the first servo motor through a coupler, at least two nuts matched with the lead screw, a belleville spring set matched between the two nuts, a sliding rail arranged on the inner wall of the side edge of a shell, and a second servo motor arranged on a sliding block matched with the sliding rail. The fixed bracket is fixed between the second servo motor and the sleeve; according to the scheme, the position and the speed of the actuator are more accurately controlled, errors are reduced and the response speed of the actuator is improved through the synergistic effect of the two motors in dual-motor driving, the two motors act simultaneously or independently, the motion state is rapidly adjusted according to different working condition requirements, the actuator can more rapidly respond to a control instruction, and the control efficiency is improved. The requirements of high-precision application scenes are met, and the overall performance and reliability of equipment are improved.

Description

Technical Field

[0001] This utility model relates to the field of electric actuator technology, specifically to a single-axis high-precision servo electric actuator. Background Technology

[0002] In the field of modern industrial automation, precise motion control is key to the efficient and stable operation of numerous devices and systems. Servo electric actuators, as devices that convert electrical energy into mechanical energy and can precisely control position, speed, and force, are widely used in various industries such as robotics, CNC machine tools, aerospace, and automated production lines.

[0003] While traditional servo electric actuators have achieved certain results in single-axis motion control, some problems still need to be solved. Regarding precision, as industrial production demands increasingly higher product quality and production efficiency, the requirements for actuator motion precision are becoming increasingly stringent. Many existing single-axis servo electric actuators, due to limitations in mechanical structure design and transmission components, struggle to meet high-precision motion control requirements. Traditional servo electric actuators use a motor to drive a belt, which in turn drives a lead screw. During the transmission process between the lead screw and the nut, factors such as backlash, friction, and manufacturing errors of components can cause deviations between the actual position of the actuator and the theoretically set position, thus affecting the control accuracy of the entire system. Utility Model Content

[0004] This utility model provides a single-axis high-precision servo electric actuator to solve the problem of poor accuracy caused by component errors and other factors in existing servo electric actuators.

[0005] To address the aforementioned problems, this utility model provides a single-axis high-precision servo electric actuator, comprising: a first servo motor, a lead screw connected to the first servo motor via a coupling, at least two nuts cooperating with the lead screw, a butterfly spring assembly cooperating between the two nuts, a sleeve welded to the bottom of the nuts, a base located at the bottom of the sleeve, a guide rail located behind the sleeve and connected via a slider, a housing located outside the guide rail, and a support frame fixed to the bottom of the housing; further comprising: a slide rail located on the inner wall of the side of the housing, a second servo motor located on a sliding block cooperating with the slide rail, and a fixed bracket fixed between the second servo motor and the sleeve;

[0006] Through the above scheme, the dual-motor drive, by the coordinated action of the two motors, more precisely controls the position and speed of the actuator, reduces errors, and improves the actuator's response speed. The two motors can operate simultaneously or individually, quickly adjusting their motion state according to different working conditions, enabling the actuator to respond to control commands more rapidly. In addition, the dual-motor drive enhances the actuator's load capacity and stability. When facing large loads or complex working conditions, the two motors can share the load, reducing the pressure on individual motors, thereby improving the reliability of the entire system, meeting the needs of high-precision application scenarios, and improving the overall performance and reliability of the equipment.

[0007] According to one embodiment of this utility model, the first servo motor is fixed above the guide rail. This solution makes full use of the space above the actuator, avoids excessive space occupation in the horizontal direction, and makes the overall structure of the actuator more compact. It can achieve more efficient installation in a limited space, which is especially suitable for equipment or systems with strict requirements for installation space. At the same time, the servo motor will generate a certain amount of heat during operation. Fixed above the guide rail with relatively open space around it, it is conducive to heat dissipation and avoids the motor performance degradation or damage caused by heat accumulation, thus ensuring the long-term stable operation of the actuator.

[0008] According to one embodiment of the present invention, a hollow shaft stepper motor is fitted onto the nut. Through the above scheme, the hollow shaft stepper motor has high-precision stepping control characteristics. After being fitted onto the nut, it replaces the second servo motor to drive the nut, achieving more precise displacement and improving the positioning accuracy and motion control accuracy of the actuator.

[0009] According to one embodiment of the present invention, the bottom of the sleeve is provided with a sleeve slider, one end of which is sleeved on the connecting rod. Several buffers are fixedly provided at the bottom of the sleeve slider. Through the above scheme, when the actuator is moving at high speed or performing frequent start-stop operations, the buffers can absorb vibration energy, reduce the accumulation of errors caused by vibration, ensure that the actuator is always in a stable operating state, and improve its working accuracy and reliability.

[0010] According to one embodiment of the present invention, the above-mentioned butterfly spring assembly adopts an asymmetrical stacking method. Compared with symmetrical stacking, the asymmetrical stacking method can make the stress distribution of the butterfly spring assembly more uniform during operation, avoid local stress concentration, reduce the risk of fatigue damage to the spring due to excessive stress, thereby extending the service life of the butterfly spring assembly and ensuring the reliable operation of the actuator.

[0011] According to one embodiment of this utility model, two locking devices are symmetrically arranged on the outer sides of the two nuts. With this design, when the actuator bears a large load, the two nuts need to share the load force. The symmetrical locking devices allow the two nuts to work together better, distributing the load evenly to each nut, preventing damage to a single nut due to excessive force, thereby improving the overall load-bearing capacity of the actuator.

[0012] According to one embodiment of this utility model, a grating ruler is installed on the side of the housing. Through the above solution, the position information of moving parts such as nuts or sleeves in the actuator can be detected in real time and accurately. Compared with the traditional position detection method, the grating ruler directly measures the displacement of the moving parts, avoiding the loss of accuracy caused by transmission errors and other factors, and improving the position detection accuracy to a higher level such as micrometers, which meets the strict requirements of high-precision servo electric actuators for position control.

[0013] According to one embodiment of the present invention, the grid window on the grating ruler is fixed to the outside of the sleeve. With the above solution, the grid window is directly fixed to the outside of the sleeve, which can achieve precise synchronization with the movement of the sleeve. The movement displacement of the sleeve is directly reflected in the movement of the grid window. The position information obtained by the grating ruler is consistent with the actual position height of the sleeve, avoiding errors caused by intermediate transmission links and greatly improving the accuracy of position measurement.

[0014] According to one embodiment of the present invention, encoders are provided on the outer sides of the first servo motor, the second servo motor, and the hollow shaft stepper motor. Through the above scheme, the encoder can accurately measure the rotation angle of the motor, thereby determining the position of the component connected to it in the actuator. When used in conjunction with position detection elements such as grating rulers, the encoder provides the initial position and relative position information of the motor end, providing an important reference for the absolute position positioning of the actuator and improving the accuracy and reliability of position control.

[0015] According to one embodiment of this utility model, the first servo motor, the second servo motor, the hollow shaft stepper motor, the grating ruler, and the encoder are all electrically connected to the controller. Through the above scheme, the controller can accurately adjust the output of the motor based on the feedback information to achieve synchronous and coordinated movement between multiple devices.

[0016] The technical advantages of this application are as follows:

[0017] This application provides a single-axis high-precision servo electric actuator that, through the coordinated action of two motors, more precisely controls the position and speed of the actuator, reduces errors, and improves the actuator's response speed. The two motors can operate simultaneously or separately, and quickly adjust their motion state according to different working conditions, enabling the actuator to respond to control commands more rapidly, meeting the needs of high-precision application scenarios, and improving the overall performance and reliability of the equipment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a single-axis high-precision servo electric actuator provided by this utility model.

[0019] Figure 2 This is a front view structural diagram of a single-axis high-precision servo electric actuator provided by this utility model.

[0020] Figure 3 This is a top view structural diagram of a single-axis high-precision servo electric actuator provided by this utility model.

[0021] Figure 4 This is a cross-sectional schematic diagram of a single-axis high-precision servo electric actuator provided by this utility model.

[0022] Figure 5 This is a schematic diagram of a double-nut structure of a single-axis high-precision servo electric actuator provided by this utility model.

[0023] Figure 6 This is a schematic diagram of the structure of a second embodiment of a single-axis high-precision servo electric actuator provided by this utility model.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. First servo motor; 2. Lead screw; 3. Nut; 4. Butterfly spring assembly; 5. Sleeve; 6. Grating ruler; 7. Guide rail; 8. Support frame; 9. Slider; 10. Base; 11. Coupling; 12. Housing; 13. Connecting rod; 14. Second servo motor; 15. Fixed bracket; 16. First pulley; 17. Belt; 18. Locking device; 19. Sleeve slider; 20. Buffer; 21. Slide rail; 22. Second pulley; 23. Hollow shaft stepper motor; 24. Limit block. Detailed Implementation

[0026] The following will be combined with the appendix Figures 1-6 The embodiments of the technical solution of this application are described in detail below. The following embodiments are only used to illustrate the technical solution of this application more clearly, and are therefore only examples and should not be used to limit the scope of protection of this application.

[0027] Example 1

[0028] Reference Figures 1-5This utility model provides a single-axis high-precision servo electric actuator, comprising: a first servo motor 1, a lead screw 2 connected to the first servo motor 1 via a coupling 11, at least two nuts 3 cooperating with the lead screw 2, a butterfly spring assembly 4 cooperating between the two nuts 3, a sleeve 5 welded to the bottom of the nuts 3, a base 10 located at the bottom of the sleeve 5, a guide rail 7 located behind the sleeve 5 and connected via a slider 9, a housing 12 located outside the guide rail 7, and a support frame 8 fixed to the bottom of the housing 12; further comprising: a slide rail 21 located on the inner side wall of the housing 12, a second servo motor 14 located on a sliding block cooperating with the slide rail 21, a first pulley 16 connected to the output shaft of the second servo motor 14, a belt 17 located outside the first pulley 16, a second pulley 22 located inside the belt 17 and located at the tension end of the belt 17, a nut 3 cooperating inside the second pulley 22, and a fixed bracket 15 fixed between the second servo motor 14 and the sleeve 5;

[0029] Through the above scheme, the dual-motor drive, by the coordinated action of the two motors, more precisely controls the position and speed of the actuator, reduces errors, and improves the actuator's response speed. The two motors can operate simultaneously or individually, quickly adjusting their motion state according to different working conditions, enabling the actuator to respond to control commands more rapidly. In addition, the dual-motor drive enhances the actuator's load capacity and stability. When facing large loads or complex working conditions, the two motors can share the load, reducing the pressure on individual motors, thereby improving the reliability of the entire system, meeting the needs of high-precision application scenarios, and improving the overall performance and reliability of the equipment.

[0030] The first servo motor 1 is fixed above the guide rail 7. This design makes full use of the space above the actuator, avoiding excessive space occupation in the horizontal direction. This makes the overall structure of the actuator more compact and enables more efficient installation in a limited space. It is especially suitable for equipment or systems with strict requirements for installation space. At the same time, the servo motor will generate a certain amount of heat during operation. Fixed above the guide rail 7, with relatively open space around it, it is conducive to heat dissipation and avoids the motor performance degradation or damage caused by heat accumulation, thus ensuring the long-term stable operation of the actuator.

[0031] The sleeve 5 is provided with a connecting rod 13 on its side. One end of the connecting rod 13 is connected to the fixing device on the side of the servo motor 1, and the other end is connected to the base 10, which further ensures that the servo motor 1 and the lead screw 2 are on the same straight line, and ensures the stable operation of the servo motor 1.

[0032] The sleeve 5 is provided with a sleeve slider 19 at the bottom. One end of the sleeve slider 19 is sleeved on the connecting rod 13. Several buffers 20 are fixedly provided at the bottom of the sleeve slider 19. Through the above scheme, when the actuator is moving at high speed or performing frequent start and stop operations, the sleeve slider 19 and the buffers 20 can limit the nut. At the same time, the buffers 20 can absorb vibration energy, reduce the accumulation of errors caused by vibration, ensure that the actuator is always in a stable operating state, and improve its working accuracy and reliability.

[0033] The nut 3 is also provided with a limiting block 24 at its top. The limiting block 24 is a general mechanical stop device used to limit the axial displacement of the nut 3 and prevent the nut 3 from moving up or down when the lead screw or belt rotates.

[0034] The aforementioned butterfly spring assembly 4 adopts an asymmetrical stacking method. Compared with symmetrical stacking, the asymmetrical stacking method makes the stress distribution of the butterfly spring assembly 4 more uniform during operation, avoids local stress concentration, reduces the risk of fatigue damage to the spring due to excessive stress, thereby extending the service life of the butterfly spring assembly 4 and ensuring the reliable operation of the actuator.

[0035] Two locking devices 18 are symmetrically arranged on the outer sides of the two nuts 3. With this design, when the actuator is subjected to a large load, the two nuts 3 need to share the load force. The symmetrical locking devices 18 can enable the two nuts 3 to work together better, distribute the load evenly on each nut 3, and prevent individual nuts 3 from being damaged due to excessive force, thereby improving the overall load-bearing capacity of the actuator.

[0036] The aforementioned housing 12 is equipped with a grating ruler 6 on its side. Through the above scheme, the position information of moving parts such as the nut 3 or sleeve 5 in the actuator can be detected in real time and accurately. Compared with the traditional position detection method, the grating ruler 6 directly measures the displacement of the moving parts, avoiding the accuracy loss caused by transmission errors and other factors, and improving the position detection accuracy to a higher level such as micrometers, which meets the strict requirements of high-precision servo electric actuators for position control.

[0037] The grid window on the grating ruler 6 is fixed to the outside of the sleeve 5. With the above scheme, the grid window is directly fixed to the outside of the sleeve 5, which can achieve precise synchronization with the movement of the sleeve 5. The movement displacement of the sleeve 5 is directly reflected in the movement of the grid window. The position information obtained by the grating ruler 6 is consistent with the actual position height of the sleeve 5, avoiding the error caused by the intermediate transmission link and greatly improving the accuracy of position measurement.

[0038] The first servo motor 1 and the second servo motor 14 are both equipped with encoders (not shown in the figure) on their outer sides. Through the above scheme, the encoder can accurately measure the rotation angle of the motor, thereby determining the position of the component connected to it in the actuator. When used in conjunction with position detection elements such as the grating ruler 6, the encoder provides the initial position and relative position information of the motor end, providing an important reference for the absolute position positioning of the actuator and improving the accuracy and reliability of position control.

[0039] The first servo motor 1, the second servo motor 14, the grating ruler 6, and the encoder are all electrically connected to the controller (not shown in the figure). Through the above scheme, the controller can accurately adjust the output of the motors based on the feedback information to achieve synchronous and coordinated movement between multiple devices.

[0040] Working principle:

[0041] The first servo motor 1, serving as the first power source, is fixed above the guide rail 7 and directly connected to the lead screw 2 via the coupling 11. The second servo motor 14, serving as the second power source, is fixed on the slide rail 21 on the side wall of the housing 12. When the controller receives a command, it sends commands to the first servo motor 1 and the second servo motor 14 to start rotating simultaneously. When the first servo motor 1 starts, its rotational motion is transmitted to the lead screw 2 via the coupling 11, causing the lead screw 2 to start rotating. When the lead screw 2 rotates, the nut 3 contains balls connected to the lead screw 2, and the balls roll along the lead screw 2. At least two nuts 3 that cooperate with the lead screw 2 will move linearly along the lead screw 2. When the second servo motor 14 starts, its rotational motion drives the first pulley 16, which in turn drives the second pulley 22 via the belt 17. The second pulley 22 then drives the nuts 3 to rotate and move linearly along the lead screw 2. A butterfly spring assembly 4 is fitted between the two nuts 3. The asymmetrical overlapping of the butterfly spring assembly 4 makes the stress distribution more uniform, reducing the risk of fatigue damage to the springs due to excessive stress and ensuring the reliable operation of the actuator. A limit block is provided at the top of the nut 3 to limit the axial displacement of the nut 3. A sleeve 5 is welded to the bottom of the nut 3. The linear movement of the nut 3 drives the sleeve 5 to move together. The rear of the sleeve 5 is connected to the guide rail 7 through the slider 9. The guide rail 7 provides guidance and support for the linear movement of the sleeve 5, ensuring that the nut 3 and the sleeve 5 can move smoothly in the predetermined direction. A grating ruler 6 is installed on the side of the housing 12. Its grid window is fixed to the outside of the sleeve 5. The grating ruler 6 can detect the position information of the sleeve 5 in the actuator in real time and accurately. Since the movement of the grid window and the sleeve 5 is precisely synchronized, errors caused by intermediate transmission links are avoided, and the accuracy of position measurement is greatly improved. An encoder is provided on the outside of the servo motor 1, which can accurately measure the rotation angle of the motor, thereby determining the position of the connected components in the actuator. The encoder, in conjunction with position detection elements such as the grating ruler 6, provides crucial reference for the absolute position positioning of the actuator. The first servo motor 1, the second servo motor 14, the grating ruler 6, and the encoder are all electrically connected to the controller. Based on feedback from each component, the controller precisely adjusts the output of either the first servo motor 1 or the second servo motor 14, achieving precise control of the actuator's position, speed, and other parameters. If either the encoder or the grating ruler 6 fails, the other component can still transmit a position signal in real time, providing high-precision double protection. The first servo motor 1 and the second servo motor 14 can start rotating simultaneously or rotate independently for high-precision execution. Furthermore, the controller can achieve synchronized and coordinated movement between multiple devices, meeting the needs of high-precision applications and improving the overall performance and reliability of the equipment.

[0042] Example 2

[0043] See attached document Figure 6Based on the above embodiment one, the single-axis high-precision servo electric actuator provided in this application also provides another embodiment, in which a hollow shaft stepper motor 23 is sleeved on the nut 3. The hollow shaft stepper motor 23 has high-precision step control characteristics. After its central output hollow shaft is sleeved on the nut 3, it replaces the second servo motor 14 to drive the nut 3, thereby achieving more precise displacement and improving the positioning accuracy and motion control accuracy of the actuator.

[0044] An encoder is provided on the outside of the hollow shaft stepper motor 23. The first servo motor 1, the hollow shaft stepper motor 23, the grating ruler 6, and the encoder are all electrically connected to the controller (not shown in the figure). The controller adjusts the output of each motor precisely based on the feedback information to achieve synchronous and coordinated movement between multiple devices.

[0045] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A single-axis high-precision servo electric actuator, characterized in that, include: A first servo motor (1), a lead screw (2) connected to the first servo motor (1) via a coupling (11), at least two nuts (3) cooperating with the lead screw (2), a butterfly spring assembly (4) cooperating between the two nuts (3), a sleeve (5) welded to the bottom of the nut (3), a base (10) located at the bottom of the sleeve (5), a guide rail (7) located behind the sleeve (5) and connected via a slider (9), a housing (12) located outside the guide rail (7), and a support frame (8) fixed to the bottom of the housing (12); It also includes: a slide rail (21) disposed on the inner side wall of the housing (12), a second servo motor (14) disposed on the sliding block that cooperates with the slide rail (21), and a fixed bracket (15) fixed between the second servo motor (14) and the sleeve (5).

2. The single-axis high-precision servo electric actuator according to claim 1, characterized in that, The first servo motor (1) is fixed above the guide rail (7).

3. The single-axis high-precision servo electric actuator according to claim 1, characterized in that, A hollow shaft stepper motor (23) is fitted onto the nut (3).

4. The single-axis high-precision servo electric actuator according to claim 1, characterized in that, The sleeve (5) has a sleeve slider (19) at the bottom. One end of the sleeve slider (19) is sleeved on the connecting rod (13). Several buffers (20) are fixedly provided at the bottom of the sleeve slider (19).

5. The single-axis high-precision servo electric actuator according to claim 1, characterized in that, The butterfly spring assembly (4) adopts an asymmetrical stacking method.

6. The single-axis high-precision servo electric actuator according to claim 1, characterized in that, Two locking devices (18) are symmetrically provided on the outer sides of the two nuts (3).

7. The single-axis high-precision servo electric actuator according to claim 3, characterized in that, A grating ruler (6) is installed on the side of the housing (12).

8. The single-axis high-precision servo electric actuator according to claim 7, characterized in that, The grid window on the grating ruler (6) is fixed to the outside of the sleeve (5).

9. The single-axis high-precision servo electric actuator according to claim 7, characterized in that, The first servo motor (1), the second servo motor (14), and the hollow shaft stepper motor (23) are all equipped with encoders on their outer sides.

10. The single-axis high-precision servo electric actuator according to claim 9, characterized in that, The first servo motor (1), the second servo motor (14), the hollow shaft stepper motor (23), the grating ruler (6), and the encoder are all electrically connected to the controller.

Images