Multi-stage programmable numerical control spin riveting device and control method thereof

Abstract

The invention provides a multi-stage programmable numerical control spin riveting device and a control method thereof. The multi-stage programmable numerical control spin riveting device comprises a rack, a control system and a servo driving system. The servo driving system comprises a Z-axis servo motor, a ball screw, a driving motor and a spin riveting head; the driving motor drives the ball screw through the Z-axis servo motor to drive the spin riveting head to move up and down. The control system comprises a multi-segment programming module capable of storing multiple sets of technological parameter combinations, each set of technological parameter combination comprises a displacement gradient, a rotating speed curve and a pressure limiting value, and the control system further comprises a displacement detection module, a rotating speed detection module and a pressure detection module. And the riveting sensors are respectively used for feeding back riveting displacement, riveting rotating speed and riveting force data to the control system in real time. According to the method, a technical closed loop of multi-parameter feedback and multi-process self-adaption is formed, manual experience dependence is replaced, and accurate matching of parameters of the whole process of pre-pressing, spinning, pressure maintaining and the like can be achieved.

Description

Technical Field

[0001] This invention relates to the field of riveting device technology, and in particular to a multi-stage programmable numerical control riveting device and its control method. Background Technology

[0002] Riveting technology is a key process that uses the combined action of rotation and axial pressure to connect workpieces. It is widely used in automotive parts, aerospace, electronic equipment and other fields. The quality of riveting directly affects the reliability and safety of products.

[0003] Existing riveting equipment has shortcomings in multi-process coordinated control and precise displacement adjustment, making it difficult to meet the requirements of high-precision and multi-variety riveting production. For example, early riveting machines were mostly mechanical or hydraulically driven, only able to achieve simple constant speed rotation and fixed pressure pressing, and could not adjust parameters such as torque, speed, and displacement speed during the riveting process. Although some CNC riveting equipment introduced servo motors to drive the riveting head to rotate and press down, they mostly only achieved parameter settings for a single stage, such as fixed speed pressing, and lacked the ability to independently program parameters for multi-stage processes such as "pre-pressing-spinning-holding pressure". Moreover, the pressure control lacked real-time feedback and could not be adaptively adjusted according to the actual condition of the workpiece.

[0004] With the development of precision manufacturing and flexible production, the market has placed higher demands on riveting equipment. However, existing technical solutions have not effectively combined the above functions, and there is an urgent need for a new type of riveting device to fill the above technological gap. Summary of the Invention

[0005] This application aims to at least solve one of the above-mentioned technical defects. In view of this, this application provides a multi-stage programmable numerical control riveting device to solve the technical defects of existing riveting devices that have single parameter settings and are difficult to meet the requirements of multi-stage process processing.

[0006] This invention provides a multi-stage programmable numerical control riveting device, including a frame, a control system, and a servo drive system;

[0007] The servo drive system includes a Z-axis servo motor mounted on the frame, a ball screw, a drive motor mounted on the ball screw, and a riveting head; the Z-axis servo motor is connected to the ball screw, the drive motor drives the ball screw to achieve vertical displacement through the Z-axis servo motor, and the riveting head is connected to the drive motor;

[0008] The control system includes a multi-segment programming module capable of storing multiple sets of process parameter combinations. Each set of process parameter combinations includes a displacement gradient, a speed curve, and a pressure limit. The control system is electrically connected to the Z-axis servo motor and the drive motor, and the control system sequentially controls the movement of the Z-axis servo motor and the drive motor according to each set of process parameter combinations.

[0009] The control system further includes a displacement detection module, a rotation speed detection module, and a pressure detection module; the displacement detection module, rotation speed detection module, and pressure detection module are respectively used to feed back riveting displacement data, riveting rotation speed data, and riveting force data to the control system in real time, and the control system adjusts the movement of the Z-axis servo motor and the drive motor according to the displacement data, riveting rotation speed data, and riveting force data combined with the current process parameters.

[0010] The device directly connects the Z-axis servo motor to the ball screw to drive the riveting head up and down, ensuring high-precision positioning and accurate riveting depth. Simultaneously, the drive motor connects to the riveting head to control its rotation, enabling stable processing of the product. The drive motor and Z-axis servo motor work together to dynamically match the pressing speed and rotational torque, precisely adapting to the process requirements of different materials. A multi-segment programming module presets multiple sets of process parameter combinations, each corresponding to the operating parameters of a processing stage, such as pre-pressing, spinning, or holding pressure. The control system, over time, sequentially adopts the corresponding parameter combinations within each stage to adjust the target displacement, speed, and pressure parameters, meeting the parameter requirements of pre-pressing, spinning, and holding pressure stages. Furthermore, the displacement detection module, speed detection module, and pressure detection module provide real-time feedback on the displacement, speed, and pressing pressure parameters of the drive motor. The control system compares these feedback parameters with the current parameter combinations, thereby adjusting the output of the Z-axis servo motor and the drive motor to achieve parameter correction. Therefore, the device can flexibly adjust process parameters and provide corresponding processing solutions for different process stages, meeting the requirements of high-precision and multi-variety riveting production and improving riveting quality.

[0011] In a preferred embodiment of the present invention, the Z-axis servo motor is connected to a torque sensor, which is used to provide real-time torque data to the control system.

[0012] The torque sensor can monitor the output torque of the Z-axis servo motor in real time, thereby ensuring that it operates within a reasonable range under the control of the control system. Specifically, this includes: 1. The output torque of the Z-axis servo motor affects the displacement state of the drive motor through the transmission structure. Therefore, this design can ensure the accuracy of the lifting and lowering motion of the drive motor and avoid inconsistent riveting depth; 2. Monitoring the torque output under different working conditions to evaluate the operating performance of the Z-axis servo motor; 3. Monitoring whether the torque is abnormal to prevent overload of the Z-axis servo motor and ensure component performance.

[0013] In a preferred embodiment of the present invention, the pressure detection module is connected to the riveting head and is used to collect pressure data in real time during the riveting process; the control system compares the pressure data with a preset threshold in real time and dynamically adjusts the output torque of the Z-axis servo motor based on the torque data.

[0014] The pressure detection module collects pressure data when the riveting head contacts the product being processed and feeds this data back to the control system for real-time comparison with preset pressure thresholds. Based on this, the control system can determine whether the riveting process involves overpressure or underpressure. Therefore, under the corresponding operating conditions, the control system can use the pressure results as a guide to adjust the output of the Z-axis servo motor in a timely manner according to the currently collected torque data, thereby regulating the downward pressure of the drive motor and keeping the pressure data within the pressure threshold, achieving a dynamic adjustment effect.

[0015] In a preferred embodiment of the present invention, a data traceability module is also included, which is used to record displacement, pressure, and rotation speed data during the riveting process and generate time-domain waveform diagrams corresponding to the displacement, pressure, and rotation speed data.

[0016] Existing equipment generally lacks comprehensive data recording capabilities. Key parameters such as torque, displacement, and pressure during the riveting process are only partially stored or lack waveform recordings, making it difficult to trace the riveting process of a specific product. This device, however, has data traceability capabilities, recording displacement, pressure, and rotational speed data during the riveting process and generating corresponding waveform diagrams, facilitating users to trace and analyze the riveting quality.

[0017] In a preferred embodiment of the present invention, the riveting head is connected to a quick-change mechanism, which is located at the connection point between the riveting head and the Z-axis servo motor.

[0018] The quick-change mechanism enables the transmission connection between the riveting head and the Z-axis servo motor, allowing for rapid replacement of the riveting head, significantly shortening production preparation time, improving the efficiency of multi-variety, small-batch production, and enhancing the equipment's versatility to adapt to various riveting needs and flexibly adjust the process. In addition, the quick-change mechanism can significantly reduce the user's operating difficulty and labor intensity.

[0019] In a preferred embodiment of the present invention, the Z-axis servo motor is connected to a reducer, and the Z-axis servo motor is connected to the ball screw through the reducer. The reduction ratio of the reducer is in the range of 1:5 to 1:10, and the displacement accuracy of the ball screw is ±0.02mm.

[0020] This design utilizes a Z-axis servo motor paired with a 1:5 to 1:10 reducer to drive a ball screw, precisely controlling the Z-axis displacement of the riveting head. The reducer converts the motor's high speed to low speed and high torque, enhancing driving force stability and avoiding pressure output fluctuations. The ball screw's high displacement accuracy of ±0.02mm ensures precise raising and lowering of the riveting head, strictly controlling the riveting position and pressure application timing. Through their combined action, high-precision coordinated control of riveting pressure and position is achieved, ensuring a stable riveting process and improving riveting quality and equipment reliability.

[0021] In a preferred embodiment of the present invention, the CNC riveting device further includes a tooling fixture disposed on the frame. The tooling fixture includes a base, a sliding plate, and a limiting gripper. The base is fixed on the frame and located below the riveting head. The sliding plate is slidably disposed on the base, and the limiting gripper is fixed on the sliding plate.

[0022] The base of the tooling fixture is installed in the machine processing area. The limiting gripper moves longitudinally or laterally in the horizontal plane through the sliding cooperation between the slide plate and the base, so as to flexibly change the riveting position. Combined with the control system and servo drive system to control the riveting depth, a dual positioning effect is achieved.

[0023] In a preferred embodiment of the present invention, the CNC riveting device further includes a protective cover and a safety light curtain. The protective cover is disposed on the frame surrounding the tooling fixture, and the safety light curtain is disposed on the edge of the protective cover. When the safety light curtain detects the intrusion of a foreign object, the control system terminates the downward pressing action of the riveting head.

[0024] The device features a protective cover surrounding the tooling fixture to prevent injury from riveting debris and protect user safety. A safety light curtain at the edge monitors for foreign object intrusion in real time, especially targeting the human hand. Upon triggering, the control system immediately stops the riveting head from pressing down, preventing accidental injury. This dual protection combines active interception and real-time monitoring, ensuring operator safety while preventing damage to workpieces or equipment due to abnormal pressure, thus improving operational safety and equipment reliability.

[0025] In a preferred embodiment of the present invention, the data tracing module further generates a pressure-displacement curve based on the time-domain waveform diagram corresponding to the displacement and pressure data.

[0026] The pressure-displacement curve can show the change of pressure with displacement during riveting, which can intuitively understand the pressure changes during the riveting process. It can be used to determine the optimal riveting pressure and displacement parameters, judge the riveting quality, and achieve precise control and quality traceability of the riveting process.

[0027] A control method, applied to the aforementioned CNC riveting device, the method comprising:

[0028] Place and secure the product to be riveted onto the frame;

[0029] After the device is started, the Z-axis servo motor drives the ball screw to lower the riveting head to the product riveting position;

[0030] The control system controls the riveting head to rotate and press down on the product to be riveted based on preset multi-stage process parameters;

[0031] The displacement detection module, speed detection module, and pressure detection module provide real-time feedback of corresponding data. Based on the data fed back by the displacement detection module, speed detection module, and pressure detection module, the control system dynamically adjusts the working state of the Z-axis servo motor and drive motor.

[0032] After riveting is completed, the data traceability module records and stores the riveting result data, forming torque, displacement, and pressure curves, and supports data export and traceability.

[0033] This method precisely controls the riveting process through multi-stage process parameters, achieving automated and high-precision riveting of the products to be riveted. A Z-axis servo motor drives the riveting head for positioning. The control system coordinates the rotation and pressing actions of the riveting head according to preset parameters, and uses displacement, speed, and pressure detection modules to monitor and provide feedback in real time, dynamically adjusting the states of the Z-axis servo motor and drive motor to ensure a stable, reliable, and consistent riveting process. After riveting is completed, the data traceability module automatically records key data such as torque, displacement, and pressure, generating curves. This supports data export and quality traceability, aiding in process optimization, problem identification, and product quality control, thereby improving production efficiency and riveting quality.

[0034] As can be seen from the above-described technical solution, the multi-stage programmable CNC riveting device provided in this application includes a frame, a control system, and a servo drive system. The servo drive system includes a Z-axis servo motor mounted on the frame, a ball screw, a drive motor mounted on the ball screw, and a riveting head. The Z-axis servo motor is connected to the ball screw, and the drive motor drives the ball screw to achieve vertical displacement via the Z-axis servo motor. The riveting head is connected to the drive motor. Compared to traditional riveting devices that use ordinary motors or pneumatic drives, this solution improves displacement accuracy through servo closed-loop control and utilizes the fast response characteristics of the servo motor to support high-speed operation, achieving a balance of high precision, high efficiency, and high reliability.

[0035] The control system includes a multi-segment programming module capable of storing multiple sets of process parameter combinations. Each set of process parameter combinations includes displacement gradient, speed curve, and pressure limit. The control system is electrically connected to the Z-axis servo motor and drive motor, and sequentially controls the movement of the Z-axis servo motor and drive motor according to each set of process parameter combinations. The control system also includes a displacement detection module, a speed detection module, and a pressure detection module. These modules are used to provide real-time feedback of riveting displacement data, riveting speed data, and riveting force data to the control system. The control system adjusts the movement of the Z-axis servo motor and drive motor based on the displacement data, riveting speed data, and riveting force data in conjunction with the current process parameter combinations. Existing riveting devices rely solely on manual experience to adjust a single parameter without real-time data feedback, resulting in unstable riveting quality, reliance on experience for debugging, and poor flexible production capabilities. In contrast, this solution uses displacement, speed, and pressure detection modules to provide real-time data feedback, and a multi-segment programming module to store multiple sets of process parameters including displacement gradients, speed curves, and pressure limits. Through multi-segment programming and parameter comparison, adaptive adjustments are made, enabling the device to meet the different process requirements of the pre-pressing, spinning, and holding stages, while taking into account high precision, high coordination, and process flexibility.

[0036] Therefore, this application's collaborative servo drive system and control system form a technical closed loop of multi-parameter feedback and multi-process adaptation, replacing reliance on manual experience and achieving precise matching of parameters throughout the entire process, including pre-pressing, spinning, and holding. This device not only dynamically adapts to the process requirements of different materials and structures, but also integrates high-precision positioning, real-time multi-parameter collaboration, and flexible multi-process control through multi-stage parameter adaptive adjustment. Ultimately, it significantly improves riveting consistency, debugging efficiency, and equipment versatility, overcoming the shortcomings of traditional technologies such as low precision, poor collaboration, and weak flexibility. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the multi-stage programmable numerical control riveting device provided in the embodiments of this application;

[0038] Figure 2 This is a schematic diagram of the servo drive system provided in the embodiments of this application;

[0039] Figure 3 This is a schematic diagram of the steps of the control method provided in the embodiments of this application.

[0040] Figure label:

[0041] 1. Frame; 2. Z-axis servo motor; 3. Ball screw; 4. Drive motor; 5. Riveting head; 6. Display; 7. Reducer; 8. Tooling fixture; 81. Base; 9. Protective cover; 10. Safety light curtain. Detailed Implementation

[0042] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0043] In the description of this invention, the terms "upper," "lower," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and are not intended to require the invention to be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0044] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” as used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0045] Existing riveting equipment has shortcomings in multi-process coordinated control and precise displacement adjustment, making it difficult to meet the requirements of high-precision and multi-variety riveting production. For example, early riveting machines were mostly mechanical or hydraulically driven, only able to achieve simple constant speed rotation and fixed pressure pressing, and could not adjust parameters such as torque, speed, and displacement speed during the riveting process. Although some CNC riveting equipment introduced servo motors to drive the riveting head to rotate and press down, they mostly only achieved parameter settings for a single stage, such as fixed speed pressing, and lacked the ability to independently program parameters for multi-stage processes such as "pre-pressing-spinning-holding pressure". Moreover, the pressure control lacked real-time feedback and could not be adaptively adjusted according to the actual condition of the workpiece.

[0046] With the development of precision manufacturing and flexible production, the market has placed higher demands on riveting equipment. However, existing technical solutions have not effectively combined the above functions, and there is an urgent need for a new type of riveting device to fill the above technological gap.

[0047] To this end, the applicant has developed a multi-stage programmable CNC riveting scheme. This scheme can match the corresponding processing parameters for the pre-pressing, spinning and holding stages in the riveting process, and make adaptive adjustments using multi-stage programming functions to improve riveting accuracy and consistency.

[0048] The following is combined with Figure 1 This application describes a programmable CNC riveting device for different stages of riveting processing, which may include a frame 1, a control system, and a servo drive system.

[0049] In actual production, existing riveting devices typically suffer from the following shortcomings when handling different processing stages of the riveting process: Most traditional devices employ fixed or relatively simple control logic, failing to set and adjust independent process parameters for each stage, resulting in abrupt transitions between stages or parameter mismatches, affecting riveting quality; simultaneously, most devices lack the ability to automatically identify and adaptively adjust the current processing stage, unable to provide real-time feedback or intelligently adjust motor speed and feed rate, making it difficult to achieve precise control and optimization at each stage; furthermore, their ability to collect and analyze key parameters in real-time during the riveting process is limited, making it difficult to detect anomalies in a timely manner and lacking the ability to provide accurate process data support for each stage, hindering quality traceability and process improvement; moreover, most devices have weak data recording and traceability functions, unable to systematically record data at each stage and display corresponding curves, making it difficult to achieve complete traceability of the processing process, affecting quality analysis and problem localization.

[0050] To solve the above problems, this application can set up a control system and a servo drive system for coordinated processing.

[0051] In practical applications, to improve the control logic, independent process parameters are set and adjusted for each stage to ensure smooth transitions or parameter matching between stages and improve riveting quality. This application can provide a servo drive system and a control system; see [link to relevant documentation]. Figure 2 As shown, the servo drive system includes a Z-axis servo motor 2, a ball screw 3, a drive motor 4 and a riveting head 5 mounted on the frame 1; the Z-axis servo motor 2 is connected to the ball screw 3, the drive motor 4 drives the ball screw 3 to achieve vertical displacement through the Z-axis servo motor 2, and the riveting head 5 is connected to the drive motor 4.

[0052] See Figure 1 As shown, the control system may include a multi-segment programming module that can store multiple sets of process parameter combinations and a display 6. Each set of process parameter combinations includes displacement gradient, speed curve and pressure limit, and can be set visually through the display 6. The control system is electrically connected to the Z-axis servo motor 2 and the drive motor 4. The control system controls the movement of the Z-axis servo motor 2 and the drive motor 4 in sequence according to each set of process parameter combinations.

[0053] Specifically, the riveting device is equipped with a servo drive system, enabling high-precision position, speed, and torque control. This ensures accurate and stable operation during pre-pressing, spinning, and holding stages, improving riveting consistency and quality. The riveting device also features a control system primarily for precise adjustment of process parameters. Simultaneously, by combining multiple preset process parameters, the system adjusts the motor speed and feed rate to achieve adaptive control, further enhancing riveting quality. Therefore, the servo drive system and control system of this application can work in coordination, optimizing the entire riveting process through the high-precision control capabilities of the servo drive system and the staged matching processing function of the control system.

[0054] The servo drive system can employ a Z-axis servo motor 2 fixed to the top of the frame 1, with its output shaft facing downwards. One end of the ball screw 3 is fixed to the output shaft of the Z-axis servo motor 2, while the other end is supported on the frame 1 via an angular contact ball bearing to ensure axial rigidity. The nut of the ball screw 3 is connected to the mounting assembly, thereby connecting to the drive motor 4 on the mounting assembly. The lower end of the drive motor 4 is fixed to the riveting head 5 via a rotating shaft. The mounting assembly can be a further configured Z-axis moving platform, such as a combination of mounting base 81, guide rails, sliders, slide plates, and brackets, to achieve fine-tuning of the drive motor 4 in the height direction. Through the above configuration, the device directly connects the Z-axis servo motor 2 and the ball screw 3 to drive the mounting assembly, ultimately causing the riveting head 5 to move up and down, ensuring high-precision positioning and accurate riveting depth. Simultaneously, the drive motor 4 is connected to the riveting head 5 to control its rotation, enabling the riveting head 5 to stably process the product to be processed. At this time, the drive motor 4 and the Z-axis servo motor 2 work together to achieve dynamic matching of pressing speed and rotational torque, accurately adapting to the process requirements of different materials.

[0055] The multi-segment programming module design is intended to meet the precise adaptation requirements of complex riveting processes. Different workpiece materials (e.g., aluminum / steel), specifications (e.g., thickness / diameter), and connection requirements (e.g., strength / deformation) necessitate differentiated process parameters. Each set of process parameters can include preset displacement values, preset rotation speed values, and upper and lower pressure thresholds corresponding to various time points in different processing stages. These preset values, thresholds, and time points constitute the displacement gradient, rotation speed curve, and pressure limits. The displacement gradient controls the riveting head's 5-stage feed, adapting to pre-compression / spinning / holding positions to ensure precise machining. The rotation speed curve adjusts rotation start / stop and speed changes, such as differences in rotation speed before and after contact, to avoid slippage or overheating. The pressure limits restrict the axial force at each stage, such as pre-compression contact force, spinning thrust, and holding pressure maintenance force, ensuring connection quality. The multi-segment programming module supports storing multiple sets of parameters, adapting to batch production of various products, and also facilitates the adjustment of parameter changes to ensure a smooth transition between multiple parameters at each stage. The visual settings allow for intuitive adjustment of parameters within the parameter combination through the display 6, reducing the risk of losses caused by missetting, and ultimately achieving efficient, stable, and flexible riveting processing.

[0056] To address the issue that most equipment lacks the ability to automatically identify and adaptively adjust to the current processing stage, and cannot provide real-time feedback, the control system also includes a displacement detection module, a speed detection module, and a pressure detection module. These modules are used to provide real-time feedback of riveting displacement data, riveting speed data, and riveting force data to the control system. The control system then adjusts the movement of the Z-axis servo motor 2 and the drive motor 4 based on the displacement data, riveting speed data, and riveting force data combined with the current process parameters.

[0057] The control system may include a displacement detection module, a speed detection module, and a pressure detection module. These three modules independently feed back their corresponding data to the control system, which then feeds this data back to the algorithm center. This data, in turn, coordinates with multiple sets of process parameters to achieve precise control. The algorithm center is understood to be a module or unit that centrally processes core control logic, data computation, or decision-making functions, such as the motion planning and servo control algorithm module in a robot controller, the temperature regulation algorithm module in a home thermostat system, or the vehicle dynamics control algorithm cluster in a vehicle domain controller. Whether it's a simple household appliance or a complex industrial or transportation system, the algorithm center is the core hub of the control system; therefore, it is an inherent part of the control system. Furthermore, the algorithm center in a CNC machine tool feed axis control system can comprehensively process displacement, speed, and pressure data. Since processing such data by the algorithm center is a current technological method, it will not be elaborated upon here.

[0058] The displacement detection module, based on the feed structure of the Z-axis servo motor 2 and ball screw 3, can use displacement sensors, such as inductive sensors or photoelectric sensors, to provide real-time feedback on the up-and-down movement position of the riveting head 5, such as the pre-press position, spinning depth, and holding pressure height, ensuring that the riveting head 5 accurately reaches the processing position. The speed detection module, based on the rotation structure of the riveting head 5, the rotating shaft, and the drive motor 4, can use photoelectric sensors or Hall effect sensors to provide real-time feedback on the current rotation speed, providing a data basis for setting the speed change before and after contacting the workpiece according to process requirements. The pressure detection module, by using a pressure sensor, exemplary arranged in the rotating shaft, can provide real-time feedback on axial pressure, such as pre-press contact force, spinning thrust, and holding pressure holding force, ensuring that the connection part is fully deformed. Each module independently transmits position, speed, and pressure data to the control system, which then comprehensively analyzes and coordinates the data. Based on the displacement data, the system compares the displacement index of the current displacement gradient to guide the riveting head 5 to feed along a preset trajectory. Combined with the speed feedback, the system compares the speed index in the current speed curve to adjust the rotational speed. Based on the pressure feedback, the system compares the pressure limit to adjust the axial force, ultimately meeting the process requirements of each stage of pre-pressing, spinning, and holding pressure, thus achieving high-precision and stable riveting processing.

[0059] Furthermore, the Z-axis servo motor 2 is connected to a torque sensor, which is used to provide real-time torque data feedback to the control system.

[0060] Specifically, when connecting the torque sensor to the Z-axis servo motor 2, it is installed at its output shaft end: the torque sensor is directly connected to the output shaft via a flexible pin coupling or a rigid coupling, and the torque sensor housing is fixed to the frame 1 or the bracket of the Z-axis servo motor 2 to ensure stability; a flexible connection, such as a flexible coupling, is used during installation to avoid rigidly fixing the torque sensor housing, allowing it to rotate freely with the shaft, while adjusting the axes of the Z-axis servo motor 2 and the torque sensor to ensure coaxiality ≤0.05mm; the sensor output end is connected to the algorithm center of the control system via a shielded cable, the shielding layer is grounded to avoid interference, and zero-point calibration is performed after installation to ensure measurement accuracy. After the above settings, the torque sensor can monitor the output torque of the Z-axis servo motor 2 in real time, thereby ensuring the accuracy of the lifting and lowering movement of the drive motor 4 under the control of the control system, avoiding inconsistent riveting depth; or monitoring the torque output under different working conditions to evaluate the operating performance of the Z-axis servo motor 2; or monitoring whether the torque is abnormal to prevent overload of the Z-axis servo motor 2 and ensure component performance.

[0061] Furthermore, the pressure detection module is connected to the riveting head 5 to collect pressure data in real time during the riveting process; the control system compares the pressure data with the preset threshold in real time and dynamically adjusts the output torque of the Z-axis servo motor 2 based on the torque data.

[0062] Specifically, the pressure detection module is directly associated with the riveting head 5 and can be installed internally or externally along the force path of the rotating shaft, such as at the shaft connection. A high-precision, impact-resistant pressure sensor, such as a strain gauge type, is selected, with a range covering process requirements and allowing for margin. Analog or digital signals are transmitted to the control system via shielded cables to collect and calibrate riveting pressure data in real time. The control system presets upper and lower pressure thresholds and compares the pressure data in real time; if the limit is exceeded, an alarm or emergency stop is triggered. Simultaneously, combined with torque data, the output torque of the Z-axis servo motor 2 is dynamically adjusted: increasing torque to compensate for insufficient pressure and reducing torque to prevent overload when the pressure exceeds the limit, ensuring a stable and reliable riveting process.

[0063] Furthermore, to enable real-time acquisition and analysis of key parameters during the riveting process, timely detection of anomalies, and the provision of accurate process data support for each stage, facilitating quality traceability and process improvement, the device also includes a data traceability module. This module records displacement, pressure, and rotational speed data during the riveting process and generates time-domain waveforms corresponding to these data. The data traceability module also generates pressure-displacement curves based on the time-domain waveforms corresponding to the displacement and pressure data.

[0064] Specifically, the data traceability module communicates with the control system via a high-precision acquisition interface, recording displacement, pressure, and rotational speed data in real time during the riveting process. A sampling frequency of ≥1kHz ensures the capture of transient changes. These three types of data are synchronously stored in a local database or cloud environment with timestamps, and can be queried by batch, work order, or time range. Through data processing algorithms, the data traceability module converts the raw acquired data into dynamic waveforms, such as displacement-time curves, pressure-time curves, and rotational speed-time curves, and generates a pressure-displacement curve, visually presenting the changing trends of key parameters and reflecting riveting stroke, stability, and equipment status. During traceability, users can retrieve the corresponding waveforms and raw values ​​by work order number or time point to analyze process deviations or abnormal events, providing data support for quality traceability, fault diagnosis, and process optimization, ensuring the riveting process is reproducible and verifiable.

[0065] Furthermore, the riveting head 5 is connected to a quick-change mechanism, which is located at the connection point between the riveting head 5 and the Z-axis servo motor 2.

[0066] Specifically, the quick-change mechanism can be configured as follows: (1) a conical surface + locking pin, with a conical surface at the end of the rotating shaft that mates with the inner conical hole of the riveting head 5 for positioning, inserting an elastic locking pin and radially tightening and fixing it manually or electrically; (2) quick-release bolts, with corresponding mounting holes on both the rotating shaft and the riveting head 5, and quick-tightening connection through multiple bolts; (3) a hydraulic or pneumatic chuck, which controls the contraction of the grippers to clamp the outer circle of the riveting head 5 to achieve connection and separation. The aforementioned design is easy to operate and can achieve quick replacement, improving efficiency.

[0067] Further, see Figure 2 As shown, the Z-axis servo motor 2 is connected to the reducer 7, and the Z-axis servo motor 2 is connected to the ball screw 3 through the reducer 7. The reduction ratio of the reducer 7 is from 1:5 to 1:10; the displacement accuracy of the ball screw 3 is ±0.02mm.

[0068] Specifically, the output shaft of the Z-axis servo motor 2 is directly connected to the input shaft of the reducer 7 via a coupling. The reducer 7 is a high-rigidity planetary reducer with a preferred reduction ratio of 1:7, which balances torque amplification and response speed. The output shaft of the reducer 7 is coaxially connected to the ball screw 3 via a rigid coupling, converting the high-speed motor to low-speed, high-torque operation, enhancing driving force stability and avoiding pressure output fluctuations. The ball screw 3 is a high-precision screw, with its lead set according to the Z-axis travel and speed requirements. The linear displacement of the ball screw 3 is calculated by the encoder built into the Z-axis servo motor 2 in conjunction with the reduction ratio, achieving an actual displacement accuracy of ±0.02mm. This ensures precise lifting and lowering of the riveting head 5, strictly controlling the riveting position and pressure application timing, and meeting the precision feed requirements in the Z-axis direction during the riveting process.

[0069] Further, see Figure 2As shown, the device also includes a tooling fixture 8 mounted on the frame 1. The tooling fixture 8 includes a base 81, a sliding plate, and a limiting gripper. The base 81 is fixed on the frame 1 and located below the riveting head 5. The sliding plate is slidably mounted on the base 81, and the limiting gripper is fixed on the sliding plate.

[0070] Specifically, the tooling fixture 8 is used to fix the workpiece to be riveted. Its structure includes: a base 81 fixed to the worktable of the frame 1 by bolts, located directly below the riveting head 5, providing stable support; a sliding plate that slides horizontally with the base 81 via a T-slot slider, adjusting its position along the X / Y directions; and limiting jaws fixed to the sliding plate by bolts, employing a replaceable structure such as a V-block, L-arm, or contouring block, adjusting the clamping point according to the workpiece shape. During operation, the jaw position is first roughly adjusted by sliding the sliding plate, and then the jaws are used to press or wrap around the workpiece, limiting its radial / axial displacement during the riveting process. This design supports quick changeover, is compatible with clamping multiple workpiece specifications, and, combined with the precise Z-axis feed of the riveting head 5, ensures consistency in riveting position and pressure.

[0071] Further, see Figure 1 As shown, the device also includes a protective cover 9 and a safety light curtain 10. The protective cover 9 is mounted on the frame 1 around the tooling fixture 8, and the safety light curtain 10 is located at the edge of the protective cover 9. When the safety light curtain 10 detects the intrusion of a foreign object, the control system terminates the downward pressing action of the riveting head 5.

[0072] Specifically, the protective cover 9 is a combination structure of a metal frame and a transparent acrylic panel, mounted on the frame 1 around the tooling fixture 8, which can isolate the riveting operation area to prevent injury from flying debris; the safety light curtain 10 can be made of through-beam infrared sensors arranged in pairs on the edge of the opening of the protective cover 9, forming a monitoring light curtain if facing the operating side. When a person's limb or other foreign object blocks the light path, the light curtain immediately sends a light-blocking trigger signal to the control system. After receiving the signal, the control system executes an emergency stop procedure, de-energizing the Z-axis servo motor 2 and the drive motor 4, forcibly terminating the rotation and pressing action of the riveting head 5, while the equipment remains locked until manually reset. This design achieves dual protection of physical isolation and photoelectric linkage, effectively avoiding safety accidents caused by accidental contact or foreign object intrusion during high-pressure riveting operations.

[0073] As can be seen from the technical solutions described above, the device provided in this application integrates a servo drive system and a control system to achieve adaptive adjustment of parameters in multiple process stages. It improves displacement accuracy through servo closed-loop control and supports high-speed operation by utilizing the fast response characteristics of servo motors. The device provides real-time data feedback through displacement, speed, and pressure detection modules, and stores multiple sets of process parameters containing displacement gradients, speed curves, and pressure limits through a multi-segment programming module. These parameters can be flexibly recalled through visualization on the display 6. This adaptive adjustment through multi-segment programming enables the device to meet the different process requirements of pre-pressing, spinning, and holding stages, while taking into account high precision, high coordination, and process flexibility.

[0074] The control method provided in the embodiments of this application is described below. See also... Figure 3 , Figure 3 This is a schematic diagram illustrating the steps of a control method disclosed in an embodiment of this application. Figure 3 As shown, the control method may include:

[0075] Step S101: Place and fix the product to be riveted on the frame;

[0076] Step S102: After the device is started, the Z-axis servo motor drives the ball screw to lower the riveting head to the product riveting position.

[0077] In step S103, the control system controls the riveting head to rotate and press down on the product to be riveted, based on preset multi-stage process parameters.

[0078] Specifically, compared with the low positioning accuracy, fixed process, and reliance on manual experience of traditional riveting devices, this solution achieves three major advantages through servo precision drive and multi-stage process control: First, it adopts a Z-axis servo motor combined with ball screw drive, which has high positioning accuracy and no backlash in transmission, avoiding deviation from the riveting position; second, it dynamically controls the rotation and pressing process based on preset multi-stage process parameters, adapting to different material requirements and avoiding cracking or deformation; third, the servo response is fast and the control is precise, improving efficiency and consistency.

[0079] In step S104, the displacement detection module, speed detection module, and pressure detection module provide real-time feedback of corresponding data. Based on the data fed back by the displacement detection module, speed detection module, and pressure detection module, the control system dynamically adjusts the working state of the Z-axis servo motor and drive motor.

[0080] Step S105: After riveting is completed, the data traceability module records and stores the riveting result data, forming torque, displacement, and pressure curves, and supports data export and traceability.

[0081] Specifically, some existing riveting devices suffer from two main problems: first, they lack real-time feedback, making it impossible to dynamically adjust the motor, resulting in low riveting accuracy and unstable quality; second, they lack data traceability, making it difficult to record and analyze riveting parameters, which is detrimental to quality control. This method, however, uses displacement, speed, and pressure detection modules to provide real-time data feedback, controlling the system to dynamically adjust the servo motor and drive motor, and correct deviations in real time, significantly improving riveting accuracy and quality stability. The data traceability module records the riveting results, supporting export and uploading to the MES system for analysis, facilitating quality control, problem tracing, and process optimization, thereby improving production reliability.

[0082] As can be seen from the technical solutions described above, the method provided in this application can dynamically adjust the motor's operating state by monitoring displacement, rotation speed, and pressure data in real time, ensuring the riveting process is accurate and stable, and significantly improving riveting quality and consistency; multi-stage process parameter control flexibly adapts to different product requirements, enhancing process adaptability; complete riveting data recording and curve generation functions support quality traceability and process analysis, facilitating problem investigation and continuous optimization, and effectively improving production efficiency and product reliability.

[0083] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0084] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Various embodiments can be combined with each other. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-stage programmable numerical control riveting device, characterized in that: Includes rack (1), control system and servo drive system; The servo drive system includes a Z-axis servo motor (2) mounted on the frame (1), a ball screw (3), a drive motor (4) mounted on the ball screw (3), and a riveting head (5); the Z-axis servo motor (2) is connected to the ball screw (3), the drive motor (4) drives the ball screw (3) to achieve vertical displacement through the Z-axis servo motor (2), and the riveting head (5) is connected to the drive motor (4); The control system includes a multi-segment programming module that can store multiple sets of process parameter combinations. Each set of process parameter combinations includes displacement gradient, speed curve and pressure limit. The control system is electrically connected to the Z-axis servo motor (2) and the drive motor (4). The control system controls the movement of the Z-axis servo motor (2) and the drive motor (4) in sequence according to each set of process parameter combinations. The control system further includes a displacement detection module, a rotation speed detection module, and a pressure detection module; the displacement detection module, the rotation speed detection module, and the pressure detection module are respectively used to feed back riveting displacement data, riveting rotation speed data, and riveting force data to the control system in real time; the control system adjusts the movement of the Z-axis servo motor (2) and the drive motor (4) according to the displacement data, riveting rotation speed data, and riveting force data combined with the current process parameters.

2. The CNC riveting device according to claim 1, characterized in that: The Z-axis servo motor (2) is connected to a torque sensor, which is used to provide real-time torque data to the control system.

3. The CNC riveting device according to claim 2, characterized in that: The pressure detection module is connected to the riveting head (5) and is used to collect pressure data in real time during the riveting process; the control system compares the pressure data with the preset threshold in real time and dynamically adjusts the output torque of the Z-axis servo motor (2) based on the torque data.

4. The CNC riveting device according to claim 1, characterized in that: It also includes a data traceability module, which is used to record displacement, pressure, and rotation speed data during the riveting process and generate time-domain waveforms corresponding to the displacement, pressure, and rotation speed data.

5. The CNC riveting device according to claim 1, characterized in that: The riveting head (5) is connected to a quick-change mechanism, which is located at the connection point between the riveting head (5) and the Z-axis servo motor (2).

6. The CNC riveting device according to claim 1, characterized in that: The Z-axis servo motor (2) is connected to a reducer (7), and the Z-axis servo motor (2) is connected to the ball screw (3) through the reducer (7); the reduction ratio of the reducer (7) is from 1:5 to 1:10, and the displacement accuracy of the ball screw (3) is ±0.02mm.

7. The CNC riveting device according to claim 1, characterized in that: The CNC riveting device also includes a tooling fixture (8) set on the frame (1). The tooling fixture (8) includes a base (81), a slide plate and a limiting gripper. The base (81) is fixed on the frame (1) and located below the riveting head (5). The slide plate is slidably set on the base (81) and the limiting gripper is fixed on the slide plate.

8. The CNC riveting device according to claim 7, characterized in that: The CNC riveting device also includes a protective cover (9) and a safety light curtain (10). The protective cover (9) is arranged around the tooling fixture (8) on the frame (1), and the safety light curtain (10) is arranged on the edge of the protective cover (9). When the safety light curtain (10) detects the intrusion of a foreign object, the control system terminates the downward action of the riveting head (5).

9. The CNC riveting device according to claim 4, characterized in that: The data tracing module also generates a pressure-displacement curve based on the time-domain waveform corresponding to the displacement and pressure data.

10. A control method, characterized in that, The CNC riveting device according to any one of claims 1-9 comprises: Place and secure the product to be riveted onto the frame; After the device is started, the Z-axis servo motor drives the ball screw to lower the riveting head to the product riveting position; The control system controls the riveting head to rotate and press down on the product to be riveted based on preset multi-stage process parameters; The displacement detection module, speed detection module, and pressure detection module provide real-time feedback of corresponding data. Based on the data fed back by the displacement detection module, speed detection module, and pressure detection module, the control system dynamically adjusts the working state of the Z-axis servo motor and drive motor. After riveting is completed, the data traceability module records and stores the riveting result data, forming torque, displacement, and pressure curves, and supports data export and traceability.

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