Method for obtaining additive wire feeding state according to feedback force and additive manufacturing device

Abstract

The application discloses a method for obtaining an additive welding wire feeding state according to a feedback force and additive processing equipment, and relates to the field of additive manufacturing. The method comprises the following steps: S10, obtaining a reference feedback force; S20, obtaining a real-time feedback force generated in a welding wire feeding process; S30, calculating a difference between the real-time feedback force and the reference feedback force to obtain a real-time feeding force; S40, calculating an average value of the real-time feeding force within a first set time to obtain a smooth feeding force; S50, if the smooth feeding force is greater than a first set threshold value, a first trigger signal is sent out to prompt that the welding wire feeding is blocked; and S60, calculating a difference between the real-time feeding force and the smooth feeding force to obtain a feeding force fluctuation value, if an absolute value of the feeding force fluctuation value is greater than a second set threshold value, a second trigger signal is sent out to prompt that the feeding stability is poor. The method can timely find the abnormal feeding state of the additive welding wire, improve the reliability of the feeding state detection, and guarantee the additive processing quality.

Description

Technical Field

[0001] This application relates to the field of additive manufacturing, specifically to a method for obtaining the wire feeding state of additive welding wire based on feedback force. Furthermore, this application also relates to additive processing equipment. Background Technology

[0002] Additive manufacturing is a technology that uses the gradual accumulation of materials to create solid parts. In a broad sense, additive manufacturing includes 3D printing, cladding, and welding. During additive manufacturing, a molten pool is typically formed on the base material at the additive processing location using lasers and / or electric arcs. The additive material is melted into the molten pool, and after solidification, the corresponding solid structure is formed. It offers advantages such as high design freedom, simple manufacturing processes, and high material utilization, and is widely used in the production of complex-shaped, customized, and small-batch parts.

[0003] Additive manufacturing typically involves a wire feeding mechanism that delivers the additive welding wire to the additive processing area of ​​the workpiece. The wire is then heated at this area, causing it to melt and fuse, forming an additive layer. During additive manufacturing, the wire feeding status has a decisive impact on the uniformity of the molten droplet transfer and the quality of the weld formation. Abnormal wire feeding speed and uniformity can lead to poor weld formation, porosity, slag inclusions, and other defects, severely affecting the mechanical properties and dimensional accuracy of the workpiece. Furthermore, the distance between the wire tip and the workpiece during arc additive manufacturing also affects the arc state. Therefore, real-time monitoring of the wire feeding status and timely identification of abnormalities are crucial for ensuring the quality of additive manufacturing.

[0004] Existing additive manufacturing equipment typically uses sensors to monitor the rotational speed of the wire feeding motor to determine the wire feeding status. However, this method struggles to identify early anomalies such as decreased wire feeding stability caused by slippage between the wire and the wire feeding wheel. Recently, methods using visual inspection to identify the wire feeding status have emerged. However, visual recognition devices are not sensitive to ambient dust and lighting conditions, and they struggle to identify the melting state of the wire tip within the molten pool, making it difficult to reliably detect and promptly address various abnormal wire feeding conditions. Summary of the Invention

[0005] In order to promptly detect abnormalities in the wire feeding status of additive welding wire, improve the reliability of wire feeding status detection, and ensure the quality of additive processing, this application provides a method and additive processing equipment for obtaining the wire feeding status of additive welding wire based on feedback force.

[0006] The method for obtaining the wire feeding state of additive welding wire based on feedback force provided in this application adopts the following technical solution: A method for obtaining the wire feeding state of additive welding wire based on feedback force includes the following steps: S10, obtaining a reference feedback force; S20, obtaining a real-time feedback force generated during the wire feeding process; S30, calculating the difference between the real-time feedback force and the reference feedback force to obtain the real-time wire feeding force; S40, calculating the average value of the real-time wire feeding force within a first set time period to obtain a smooth wire feeding force; S50, if the smooth wire feeding force is greater than a first set threshold, issuing a first trigger signal to indicate that the wire feeding is obstructed; S60, calculating the difference between the real-time wire feeding force and the smooth wire feeding force to obtain a wire feeding force fluctuation value; if the absolute value of the wire feeding force fluctuation value is greater than a second set threshold, issuing a second trigger signal to indicate poor wire feeding stability.

[0007] By adopting the above technical solution, the feedback force driving the welding wire forward during the wire feeding process is used as the detection basis. The force state directly related to the wire feeding state can be detected directly, unaffected by fluctuations in electrical parameters and lighting environment, and the detection results are accurate and reliable. The real-time wire feeding force is obtained by using the difference between the real-time feedback force and the reference feedback force, eliminating fixed feedback force components such as the weight of the wire feeding mechanism itself and the wire feeding resistance, and obtaining the wire feeding force that truly reflects the wire's forward state. Thus, the wire feeding force can accurately reflect the wire's forward state. By calculating the average value of the real-time wire feeding force within a short first set time, a smoothed wire feeding force is obtained, which can reduce the interference of occasional factors on the wire feeding state judgment and ensure the accuracy of wire feeding state detection. The wire feeding stability is evaluated by using the wire feeding force fluctuation value, which can identify wire feeding speed fluctuations caused by wire feeding wheel wear, poor wire straightening, and uneven wire diameter, increasing the identification dimension of the wire feeding state and contributing to further improvement of additive manufacturing quality.

[0008] In one specific implementation, in step S10, the reference feedback force is obtained by the control system from historical storage records.

[0009] By adopting the above technical solution and using historical stored data as the reference feedback force, it is not necessary to recalibrate the reference feedback force every time the device is powered on, which improves the device startup efficiency and the operational stability in the initial startup state.

[0010] In one specific implementation, in step S20, the real-time feedback force generated during the wire feeding process is obtained by setting a fixed part and a movable part on the wire feeding mechanism, setting a wire feeding driver on the movable part, and setting a stress sensor between the fixed part and the movable part.

[0011] By adopting the above technical solution, using the wire feed driver installed on the moving part, a corresponding reaction force can be generated on the moving part while driving the welding wire forward, which is the feedback force that drives the welding wire forward. The real-time feedback force can be detected by the stress sensor set between the moving part and the fixed part, and the changes in the wire feeding state can be accurately detected through the real-time feedback force.

[0012] In one specific implementation, the method for acquiring the real-time feedback force is to acquire it periodically at a set time interval, with an acquisition frequency of 20-200 times / second.

[0013] By adopting the above technical solution and setting a reasonable sampling frequency, it is possible to ensure the dynamic capture of changes in feedback force and detect short-term fluctuations in wire feeding status, while avoiding excessively high sampling frequencies that would burden data processing, thus balancing real-time detection and system operating efficiency.

[0014] In one specific implementation, in step S40, the first set time is 20-100 times the real-time feedback force acquisition cycle.

[0015] By adopting the above technical solution, using 20-100 times the real-time feedback force acquisition cycle as the first set time, it is possible to effectively filter out the instantaneous random interference of the real-time feedback force while retaining the actual changes in the wire feeding state, thus ensuring the timeliness and accuracy of the detection of changes in the wire feeding state.

[0016] In a specific implementation scheme, the method of obtaining the wire feeding state of additive welding wire based on feedback force in this application further includes the following steps: S55, obtaining the working state of the additive processing equipment; if the additive processing equipment is in the preparation state when the first trigger signal is issued, controlling the wire feeding mechanism to reverse the action and drive the welding wire to return a set distance; if the additive processing equipment is in the additive processing state when the first trigger signal is issued, controlling the additive processing equipment to increase the welding power and / or decrease the wire feeding speed.

[0017] By adopting the above technical solution, when the additive processing equipment is in the ready state and the first trigger signal is issued, the welding wire is controlled to retract a set distance. The position of the workpiece can be accurately judged by the obstruction of the welding wire by the workpiece, and the distance between the end of the welding wire and the workpiece can be controlled at the beginning of additive processing to ensure the stable formation of the additive processing state. When the first trigger signal is issued during the processing stage, the temperature of the molten pool can be increased by increasing the welding power, thereby increasing the melting speed of the welding wire in the molten pool. By reducing the wire feeding speed, the melting time of the welding wire in the molten pool can be increased, avoiding the presence of solid welding wire in the molten pool, which would lead to slag inclusions and poor weld formation.

[0018] In one specific implementation, in step S50, if the smoothing wire feeding force is greater than a first set threshold, a first trigger signal is issued and maintained; if the smoothing wire feeding force is less than the first set threshold, the first trigger signal is revoked.

[0019] By adopting the above technical solution, and utilizing the trigger signal to change accordingly with the change of wire feeding state, the additive manufacturing equipment can adjust its parameters according to the change of wire feeding state, thereby achieving automatic adjustment of the wire feeding state without manual intervention.

[0020] In one specific implementation, the method further includes step S57: if the smooth wire feeding force is less than a third set threshold, a third trigger signal is issued to indicate that the welding wire is sliding in the wire feeding mechanism.

[0021] By adopting the above technical solution, the identification of the state where the smooth wire feeding force is lower than the set threshold can detect the abnormal wire feeding caused by the low friction of the wire feeding wheel. This further expands the scope of abnormal wire feeding identification and can cover abnormal scenarios such as insufficient wire feeding wheel clamping force and excessive lubrication of the welding wire surface, which is conducive to the detection and correction of more abnormal wire feeding states.

[0022] In one specific implementation scheme, the method further includes step S70: if the absolute value of the wire feeding force fluctuation value is continuously less than a fourth set threshold within a second set time, then calculate the average value of the real-time feedback force within the second set time and replace the original reference feedback force with it; the second set time is greater than 20 times the first set time.

[0023] By adopting the above technical solution, the automatic updating of the reference feedback force during long-term stable operation of the wire feeding mechanism can adaptively compensate for the reference drift caused by slow-changing factors such as mechanism wear and changes in ambient temperature. This ensures the accuracy of feedback force detection and wire feeding status judgment during long-term operation of the wire feeding mechanism and reduces manual intervention during the work process.

[0024] The additive manufacturing equipment provided in this application can realize the method of obtaining the feeding state of additive welding wire based on feedback force provided in this application, and also has the advantages of the method of obtaining the feeding state of additive welding wire based on feedback force provided in this application.

[0025] In summary, this application includes at least one of the following beneficial technical effects: By using mechanical feedback force as the detection basis, the feedback force state directly related to the wire feeding state can be obtained. The detection process is not affected by fluctuations in electrical parameters, ambient lighting conditions, etc. The feedback force detection has higher stability and can more accurately determine the wire feeding state. By detecting and judging various changes in wire feeding force, it is possible to accurately identify various abnormal wire feeding states such as wire feeding obstruction, poor wire feeding stability, and wire feeding slippage. This provides a basis for targeted handling of different types of abnormal states, which helps to ensure the stability of wire feeding state and guarantee the quality of additive manufacturing. By smoothing the wire feeding force and calculating the fluctuation value of the real-time wire feeding force, the overall trend and dynamic fluctuation characteristics of the wire feeding resistance can be evaluated respectively. This can avoid misjudgment caused by instantaneous interference and sensitively capture short-term fluctuations in the wire feeding force. It takes into account both the reliability and sensitivity of feedback force detection, which helps to accurately obtain various abnormal wire feeding states and to handle different abnormal states in a targeted manner. By automatically updating the reference feedback force, it can adapt to the slow drift of the feedback force caused by equipment wear and environmental changes. This is beneficial for accurately improving the wire feeding force, which is more closely related to the wire feeding state, from the feedback force, ensuring the accurate acquisition of the wire feeding state and the long-term stable operation of the additive manufacturing equipment.

[0026] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0027] Figure 1 This is a flowchart of an embodiment of the method for obtaining the wire feeding state of additive welding wire based on feedback force according to this application.

[0028] Figure 2 This is a control flowchart of one embodiment of the method for obtaining the wire feeding state of additive welding wire based on feedback force according to this application.

[0029] Figure 3 This is a schematic diagram of the wire feeding mechanism in one embodiment of the additive manufacturing equipment of this application.

[0030] Explanation of reference numerals in the attached drawings: 1. Fixed component; 2. Moving component; 21. Rotating shaft; 3. Wire feed driver; 31. Drive motor; 32. Transmission gear; 33. Wire feed wheel; 4. Stress sensor; 5. Welding wire. Detailed Implementation

[0031] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0032] In this application, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first", "second", "third", or "fourth" may explicitly or implicitly include one or more of the stated features.

[0033] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] One embodiment of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application is as follows: Figure 1 and Figure 2 As shown, it includes the following steps: S10, Obtain the reference feedback force.

[0035] The reference feedback force can be obtained by the control system through an input terminal, such as a touch screen, manually input by the operator based on historical experience, retrieved by the control system from historical data stored in the storage unit, or temporarily used as the reference feedback force by the control system and automatically adjusted in subsequent work processes.

[0036] S20. Obtain the real-time feedback force generated during the wire feeding process.

[0037] Welding wire is typically fed to the additive manufacturing area of ​​the workpiece by a wire feeding mechanism. Under the influence of a laser or electric arc, it melts into a molten pool on the workpiece, forming an additive manufacturing process. During wire feeding, a feedback force is generated on the wire feeding mechanism in the opposite direction to the wire feeding direction. The magnitude of this feedback force is closely related to the wire feeding state: an increase in wire feeding speed increases the feedback force on the feeding mechanism; an increase in the wire's forward resistance also increases the feedback force. Therefore, by monitoring the changes in the feedback force acting on the wire feeding mechanism, changes in the wire feeding state can be obtained.

[0038] S30. Calculate the difference between the real-time feedback force and the reference feedback force to obtain the real-time wire feeding force.

[0039] The welding wire is typically fed forward in a wire guide tube, which guides the wire's path and ensures that the wire tip is accurately delivered to the molten pool in the additive section of the workpiece, where it melts and forms an additive component. As the welding wire moves through the wire guide tube, it rubs against the inner wall, generating resistance. This frictional resistance usually remains constant throughout the wire's movement and is largely independent of the wire feeding state, yet it still creates a feedback force on the wire feeding mechanism. The reference feedback force, as used in this application, reflects a feedback force that remains relatively constant during wire feeding and is largely unaffected by changes in the wire feeding state. Examples include the frictional force of the wire moving through the wire guide tube and the rotational resistance of the wire feeding wheel that drives the wire forward.

[0040] By calculating the difference between the real-time feedback force and the reference feedback force, the fixed component in the real-time feedback force that is not closely related to the wire feeding state can be removed. The resulting real-time wire feeding force can more accurately reflect the wire feeding state and improve the sensitivity to changes in the wire feeding state.

[0041] The real-time wire feeding force is usually obtained by subtracting the real-time feedback force and the reference feedback force from the computing unit in the controller. It can also be implemented by a dedicated subtraction circuit. The relevant implementation methods are conventional technologies in this field and will not be described in detail in this application.

[0042] S40. Calculate the average value of the real-time wire feeding force within the first set time to obtain the smooth wire feeding force.

[0043] The feedback force of the wire feeding mechanism during wire feeding is easily affected by various accidental interference factors. These interference factors can easily cause sudden and significant changes in the real-time wire feeding force, affecting the accurate judgment of the wire feeding status. By calculating the average value of the wire feeding force over a certain period of time, the interference of accidental factors on the wire feeding force can be significantly reduced, thereby improving the accuracy of obtaining the wire feeding status.

[0044] The longer the first set time is, the better the suppression effect on occasional interference factors. However, a long first set time will make it difficult for the average wire feeding force to reflect the short-term changes in the real-time wire feeding force, thus reducing the sensitivity to changes in the real-time wire feeding force.

[0045] The initial set time is usually determined in conjunction with the wire feeding speed and is typically set to less than 1 second. Alternatively, the initial set time can be determined based on the acquisition cycle of the real-time feedback force, usually set to the time of 3-10 acquisition cycles of the real-time feedback force.

[0046] The system continuously sends the smoothing wire feeding force to the host computer via the serial port, and the host computer records the dynamic changes of the smoothing wire feeding force throughout the entire working process.

[0047] S50. Determine whether the feeding of the welding wire is obstructed based on the magnitude of the smooth wire feeding force.

[0048] When the feeding of welding wire is obstructed, the resistance to the wire's advance will increase significantly, and the feedback force on the wire feeding mechanism will also increase significantly. By monitoring the wire feeding feedback force, abnormal situations such as obstruction of welding wire feeding can be detected in a timely manner.

[0049] If the wire feeding force increases significantly, exceeding the first set threshold, it usually indicates that the wire feeding is obstructed. At this point, the system issues a first trigger signal. The first trigger signal can be a control signal transmitted internally within the system, serving as the basis for automatic system adjustments; or it can be an external warning signal, such as the illumination or flashing of an indicator light, used to remind the operator to intervene.

[0050] Wire feeding obstruction can be caused by the end of the wire contacting the workpiece and being unable to continue moving forward, or by deformation or interruption of the wire feeding channel under external force, resulting in a significant increase in wire feeding resistance or jamming. The first set threshold can be obtained by simulating various situations of wire feeding obstruction and by appropriately adjusting the smooth wire feeding force according to the magnitude of the obstruction.

[0051] S60. Determine the stability of the welding wire feeding based on the difference between the real-time wire feeding force and the smooth wire feeding force.

[0052] During the wire feeding process, various factors can cause periodic fluctuations in the wire feeding state. These include localized wear of the wire feed rollers that propel the wire forward, periodic bending of the wire due to poor wire straightening, and periodic slippage between the wire and the wire feed rollers due to insufficient clamping force. Under these conditions, the real-time wire feeding force will undergo rapid periodic changes, while the smooth wire feeding force may remain stable.

[0053] The wire feeding force fluctuation value, obtained by calculating the difference between the real-time wire feeding force and the smooth wire feeding force, can accurately reflect the periodic changes in the real-time wire feeding force. By setting a reasonable second threshold, the magnitude of the wire feeding force fluctuation value can be monitored. If the absolute value of the wire feeding force fluctuation value is greater than the second threshold, it indicates that the fluctuation of the welding wire feeding state has reached a level that affects the additive manufacturing quality. At this time, the system issues a second trigger signal, such as illuminating a specific color indicator light or controlling the indicator light to flash in a set pattern, to remind the staff to intervene.

[0054] The second threshold can be determined based on the material and specifications of the welding wire and the precision requirements of additive manufacturing. Specifically, it can be determined based on historical operating experience or by simulating the corresponding abnormal conditions.

[0055] In some embodiments of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, in step S10, the reference feedback force is obtained by the control system from historical storage records.

[0056] In actual operation, the system stores the reference feedback force in the storage unit. After the work is completed, the system retains the reference feedback force used in the previous work in the storage unit. When the next work begins, the system directly retrieves the reference feedback force used in the previous work from the storage unit, thus eliminating the need to recalibrate the reference feedback force every time the device is powered on, simplifying the device startup process and improving the efficiency of device startup.

[0057] In some embodiments of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, such as Figure 3 As shown, the wire feeding mechanism includes a fixed component 1, a movable component 2, a wire feeding driver 3, and a stress sensor 4. The fixed component 1 is fixed to the additive manufacturing equipment. The movable component 2 is rotatably mounted on the fixed component 1 via a rotating shaft 21. The wire feeding driver 3 is located inside the movable component 2. Corresponding wire feeding channels are provided in the fixed component 1 and the movable component 2. The welding wire 5 enters the wire feeding channel from the top of the movable component 2 and exits from the bottom of the fixed component 1. The stress sensor 4 is located on the opposite surfaces of the fixed component 1 and the movable component 2, with its periphery fixedly connected to the fixed component 1 and its center fixedly connected to the movable component 2.

[0058] The wire feed driver 3 includes a drive motor 31, a transmission gear 32, and two wire feed rollers 33. The two wire feed rollers 33 are respectively located on opposite sides of the wire feeding channel. The drive motor 31 drives the wire feed rollers 33 to rotate via the transmission gear 32, pushing the welding wire 5, which is clamped between the two wire feed rollers 33, through the fixed component 1 and conveying it towards the workpiece. While the wire feed rollers 33 push the welding wire 5 downwards, the welding wire 5 generates a feedback force that pushes the wire feed rollers 33 upwards. This feedback force acts on the movable component 2, creating a tendency for the movable component 2 to rotate upwards around the rotation axis 21, causing the stress sensor 4 to detect the feedback force.

[0059] When using the wire feeding mechanism of this embodiment, the detection value of the stress sensor 4 before the drive motor 31 is activated can also be used as the initial reference feedback force to obtain the real-time wire feeding force.

[0060] In step S20, the system obtains the feedback force when the wire feeding wheel 33 pushes the welding wire 5 forward through the stress sensor 4, which can conveniently obtain the real-time feedback force generated during the welding wire feeding process.

[0061] In a preferred embodiment of the method for obtaining the wire feeding status of additive welding wire based on feedback force in this application, the real-time feedback force is periodically sampled at set time intervals. The sampling frequency of the real-time feedback force is set to 20-200 times / second, preferably 100 times / second, that is, real-time feedback force data is collected at a sampling frequency of 100Hz. Such a sampling frequency can capture the dynamic fluctuations of the real-time feedback force during wire feeding without generating excessive data processing volume, thus balancing detection real-time performance and system operating efficiency.

[0062] As a specific embodiment of the method for obtaining the wire feeding state of additive welding wire based on feedback force according to this application, in step S40, the first set time is set to 20-100 times the real-time feedback force acquisition cycle, preferably 50 times the real-time feedback force acquisition cycle. For example, when acquiring real-time feedback force data at a sampling frequency of 100Hz, the first set time is set to 50 times the real-time feedback force acquisition cycle, with 0.5 seconds as the first set time. That is, the arithmetic mean of the real-time wire feeding force within 50 consecutive sampling cycles is calculated to obtain the smoothed wire feeding force.

[0063] By using smooth wire feeding force as the basis for judging the wire feeding force state, it is possible to effectively avoid the interference of instantaneous and accidental factors on the changing trend of the wire feeding force state, which could lead to misjudgment of the wire feeding state.

[0064] In some embodiments of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, such as Figure 1 and Figure 2 As shown, the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application further includes the following steps: S55. When the system issues the first trigger signal, it performs targeted processing according to the different working states of the additive manufacturing equipment.

[0065] The working status of the additive manufacturing equipment can be obtained from its control system. If the control system is powered on but has not yet entered the working cycle, it means that the additive manufacturing equipment is in the preparation state; if the control system has entered the working cycle, it means that the additive manufacturing equipment is in the additive manufacturing state.

[0066] When the additive manufacturing equipment is in the ready state, the additive laser or arc power supply has not yet been activated. The welding wire will not be heated and melted when it advances into the additive manufacturing area of ​​the workpiece. As a result, the tip of the welding wire contacts the workpiece and is obstructed. In this state, a first trigger signal is issued to confirm that the tip of the welding wire has contacted the workpiece. At this point, the wire feeding mechanism is controlled to reverse, driving the welding wire back a set distance, ensuring that the tip of the welding wire is positioned at a predetermined distance from the workpiece surface. Controlling this position facilitates the formation of a molten pool on the surface of the workpiece irradiated by the laser in laser additive manufacturing equipment, or the formation and control of the arc shape in arc additive manufacturing equipment.

[0067] When the additive manufacturing equipment is in additive manufacturing mode, the tip of the welding wire enters the molten pool on the workpiece surface as it is fed. Under the high temperature of the molten pool and the heating effect of laser irradiation or electric arc, it melts in the molten pool, forming additive manufacturing on the workpiece surface. In this state, a first trigger signal is issued, indicating that the tip of the welding wire has not melted in time and has reached the bottom of the molten pool and is obstructed. At this point, the welding power of the additive manufacturing equipment can be increased, that is, the power of the laser irradiation or the electric arc power supply can be increased. This improves the heating effect of the laser or electric arc on the workpiece surface and the tip of the welding wire, allowing the tip of the welding wire to melt more quickly. Alternatively, the speed of the welding wire feed in the additive manufacturing equipment can be reduced, thereby extending the time from the entry of the welding wire into the molten pool to contact the bottom of the molten pool, allowing the welding wire more time to melt in the molten pool. Both methods can prevent slag inclusions from forming in the molten pool due to the influence of solid welding wire, thus affecting the quality of the weld. Increasing the welding power and reducing the wire feed speed of the additive manufacturing equipment can be used individually or simultaneously. When both are used simultaneously, the increase in welding power and the decrease in wire feed speed can be controlled separately. The specific control strategy adopted can be determined based on the additive manufacturing process requirements, combined with the current molten pool temperature and current wire feed speed.

[0068] Of course, the first trigger signal may also be triggered by unexpected factors such as mechanical obstruction of the welding wire by an external structure or a malfunction of the wire guide tube. In this case, the above operations cannot reset the first trigger signal, and the first trigger signal will persist, prompting the staff to intervene manually.

[0069] In a preferred embodiment of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, such as Figure 2 As shown, in step S50, when the smoothing feeding force is greater than the first set threshold, the trigger system issues a first trigger signal. Before the next detection of the real-time feedback force and recalculation of the real-time feeding force and smoothing feeding force, the trigger state of the first trigger signal is maintained. If the smoothing feeding force obtained from the next detection and calculation is still greater than the first set threshold, the trigger state of the first trigger signal is maintained. If the result of the next detection and calculation makes the smoothing feeding force less than the first set threshold, the first trigger signal is reset, and the existing first trigger signal is canceled.

[0070] In some embodiments of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, such as Figure 1 and Figure 2 As shown, the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application further includes the following steps: S57. If the smoothing force is less than the third set threshold, issue a third trigger signal.

[0071] A decrease in the smooth wire feeding force usually indicates a decrease in the driving force between the wire feeding wheel and the welding wire, typically suggesting slippage between the welding wire and the wire feeding wheel. Wire slippage is usually caused by a decrease in the clamping force of the wire feeding wheel, and is often accompanied by an increase in wire feeding resistance. At this point, the system issues a third trigger signal, alerting the operator to intervene manually in a timely manner, thus preventing large-area defects in the weld.

[0072] When the welding wire slides in the wire feeding wheel, the friction will decrease. At this time, the real-time feedback force will be lower than the reference feedback force, making the real-time wire feeding force and the smooth wire feeding force less than zero. Therefore, the third set threshold is usually also less than zero.

[0073] In some embodiments of the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application, such as Figure 1 and Figure 2 As shown, the method for obtaining the wire feeding state of additive welding wire based on feedback force in this application further includes the following steps: S70: Automatically recalibrate the reference feedback force by utilizing the average real-time feedback force during long-term stable operation of the system.

[0074] During operation, the fluctuation value of the wire feeding force is continuously monitored. If the absolute value of the fluctuation value is consistently less than the third set threshold over a relatively long second set time period, it indicates that the wire feeding mechanism is stable and unchanged during that time period. The real-time feedback force at this time reflects the basic resistance encountered during the wire feeding process. Then, the average value of all real-time feedback forces detected within the second set time period is calculated, and the original reference feedback force is replaced by this average value to automatically update the reference feedback force.

[0075] The second set time is usually set much longer than the first set time, such as more than 20 times the first set time, preferably 50 times the first set time. If the first set time is 0.5 seconds, the second set time is preferably set to 25 seconds. If the absolute value of the yarn feeding force fluctuation value remains close to zero and less than the third set threshold within 25 seconds, the average value of the real-time feedback force during this period is used to update the reference feedback force.

[0076] By automatically updating the reference feedback force, it can automatically adapt to the drift of the reference feedback force caused by factors such as wear of the wire feeding mechanism, changes in ambient temperature, and slow changes in preload, ensuring the detection accuracy of the equipment under long-term operation and reducing the maintenance workload of manual calibration.

[0077] The additive manufacturing equipment of this application includes a wire feeding mechanism, which can realize the method of obtaining the wire feeding state of additive welding wire based on feedback force according to any embodiment of this application, and also has the advantages of the method of the corresponding embodiment.

[0078] In the description of this application, the references to terms such as "an embodiment," "specific embodiment," and "preferred embodiment" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0079] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for obtaining the wire feeding state of additive welding wire based on feedback force, characterized in that, Includes the following steps: S10, Obtain the reference feedback force; S20. Obtain the real-time feedback force generated during the wire feeding process; S30. Calculate the difference between the real-time feedback force and the reference feedback force to obtain the real-time wire feeding force; S40. Calculate the average value of the real-time wire feeding force within the first set time to obtain the smooth wire feeding force; S50. If the smooth wire feeding force is greater than the first set threshold, issue the first trigger signal to indicate that the wire feeding is blocked. S60. Calculate the difference between the real-time wire feeding force and the smooth wire feeding force to obtain the wire feeding force fluctuation value. If the absolute value of the wire feeding force fluctuation value is greater than the second set threshold, issue a second trigger signal to indicate poor wire feeding stability.

2. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 1, characterized in that, In step S10, the reference feedback force is obtained by the control system from historical storage records.

3. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 2, characterized in that, In step S20, the real-time feedback force generated during the wire feeding process is obtained by setting a fixed part and a movable part on the wire feeding mechanism, setting a wire feeding driver on the movable part, and setting a stress sensor between the fixed part and the movable part.

4. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 3, characterized in that, The method for obtaining the real-time feedback force is to periodically obtain it at a set time interval, with a frequency of 20-200 times / second.

5. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 4, characterized in that, In step S40, the first set time is 20-100 times the real-time feedback force acquisition cycle.

6. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 1, characterized in that, It also includes the following steps: S55, obtaining the working status of the additive processing equipment; if the additive processing equipment is in the preparation state when the first trigger signal is issued, then controlling the wire feeding mechanism to reverse the action and drive the wire to return to the set distance; if the additive processing equipment is in the additive processing state when the first trigger signal is issued, then controlling the additive processing equipment to increase the welding power and / or decrease the wire feeding speed.

7. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 6, characterized in that, In step S50, if the smoothing force is greater than the first set threshold, a first trigger signal is issued and maintained; if the smoothing force is less than the first set threshold, the first trigger signal is canceled.

8. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to claim 1, characterized in that, It also includes step S57: if the smooth wire feeding force is less than the third set threshold, issue a third trigger signal to indicate that the welding wire is sliding in the wire feeding mechanism.

9. The method for obtaining the wire feeding state of additive welding wire based on feedback force according to any one of claims 1-8, characterized in that, It also includes step S70: if the absolute value of the wire feeding force fluctuation value is continuously less than the fourth set threshold within the second set time, then calculate the average value of the real-time feedback force within the second set time and replace the original reference feedback force with it. The second set time is more than 20 times the first set time.

10. An additive manufacturing apparatus, characterized in that, This includes a method capable of obtaining the wire feeding state of additive welding wire based on feedback force according to any one of claims 1-9.

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