Control method and control system

Abstract

The application provides a control method and a control system for adjusting the locking process of an electric screwdriver. The control method comprises the following steps: obtaining the model of a component to be locked; determining the set position of the locking hole of the component to be locked on the locking end face according to the model of the component to be locked; determining the initial position of the electric screwdriver according to the set position, wherein the initial position is directly above the set position; controlling the electric screwdriver to move downwards in the direction of approaching the component to be locked after moving to the initial position, and obtaining the positioning torque of the electric screwdriver during the movement downwards; determining whether the electric screwdriver is oppositely arranged with the locking hole according to the size of the positioning torque; and entering the position adjustment process of adjusting the position of the electric screwdriver relative to the locking hole to make the electric screwdriver oppositely arranged with the locking hole in the case of determining that the electric screwdriver is misaligned with the locking hole. The technical scheme of the application can effectively solve the technical problems of low manual locking precision and high cost of visual system assisted locking in the prior art.

Description

Technical Field

[0001] This invention relates to the field of screw fastening technology, and more specifically, to a control method and a control system. Background Technology

[0002] Currently, in the process of fixing air conditioner motor brackets, traditional methods usually rely on manual screw fastening or industrial robots combined with vision systems to perform the fastening operation.

[0003] However, manual assembly is not only inefficient but also susceptible to the operator's skill and physical condition, making it difficult to guarantee assembly accuracy and consistency. Especially when operating continuously on a production line, the cumulative fatigue of manual operators further reduces assembly efficiency and quality. While using industrial robots with vision systems can improve automation and accuracy, their high cost and complex system integration pose a significant economic and technical burden on small and medium-sized enterprises. Summary of the Invention

[0004] The main objective of this invention is to provide a control method and control system to solve the technical problems of low accuracy of manual locking and high cost of vision system-assisted locking in the prior art.

[0005] To achieve the above objectives, according to one aspect of the present invention, a control method is provided, the control method being used to regulate the fastening process of an electric screwdriver, the control method comprising:

[0006] Obtain the model number of the component to be locked, determine the set position of the locking hole of the component to be locked on the locking end face according to the model number of the component to be locked, determine the initial position of the electric screwdriver according to the set position, and the initial position is located directly above the set position;

[0007] After the electric screwdriver is moved to the initial position, it moves downward toward the component to be locked, and the positioning torque received by the electric screwdriver during the downward movement is obtained.

[0008] The magnitude of the positioning torque determines whether the electric screwdriver is positioned relative to the locking hole; and if it is determined that the electric screwdriver is misaligned with the locking hole, a position adjustment process is initiated to adjust the position of the electric screwdriver relative to the locking hole so that the electric screwdriver is positioned relative to the locking hole.

[0009] Further, the step of controlling the electric screwdriver to move downwards towards the component to be locked after reaching the initial position, and obtaining the positioning torque experienced by the electric screwdriver during the downward movement, includes:

[0010] The position of the screw-locking point of the electric screwdriver is determined based on the first height difference between the initial position and the set position, and the second height difference between the position of the screw-locking point and the set position is greater than the first height difference;

[0011] The electric screwdriver is controlled to move downwards to the screw-locking point, and the positioning torque of the electric screwdriver during the downward movement to the screw-locking point is obtained.

[0012] Further, determining whether the electric screwdriver is aligned with the locking hole based on the magnitude of the positioning torque includes:

[0013] The maximum value of the positioning torque of the electric screwdriver during its downward movement to the screw-locking point is obtained as the first torque, and the first torque is compared with the first preset torque.

[0014] If the first torque is greater than the first preset torque, it is determined that the electric screwdriver and the locking hole are misaligned.

[0015] If the first torque is less than or equal to the first preset torque, it is determined that the electric screwdriver and the locking hole are positioned opposite each other.

[0016] Furthermore, the position adjustment process for adjusting the position of the electric screwdriver relative to the locking hole includes:

[0017] The electric screwdriver is controlled to move from the screw-locking point to a first preset position along a first preset direction on the radial plane of the locking hole, and the minimum value of the positioning torque experienced by the electric screwdriver during the process of moving to the first preset position is obtained as a second torque. The second torque is compared with the first torque, where the first torque is the maximum value of the positioning torque of the electric screwdriver during the downward movement.

[0018] When the second torque is greater than or equal to the first torque, it is determined that the electric screwdriver is moving in the wrong direction, and the electric screwdriver is controlled to return to the screw-locking point.

[0019] When the second torque is less than the first torque, it is determined that the moving direction of the electric screwdriver is correct, the second torque is determined to be the initial positioning torque, and it is determined whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0.

[0020] Wherein, the positional difference between the first preset position and the screw point is greater than or equal to the production error of the locking hole.

[0021] Furthermore, after controlling the electric screwdriver to return to the screw-locking position, the control method further includes:

[0022] The electric screwdriver is controlled to move along a second preset direction opposite to the first preset direction to a second preset position, and the minimum value of the positioning torque received by the electric screwdriver when it moves to the second preset position is obtained as a third torque. The third torque is determined as the initial positioning torque, and the position adjustment process is determined again based on the comparison between the initial positioning torque and 0.

[0023] Wherein, the positional difference between the second preset position and the screw position is greater than or equal to the production error of the locking hole.

[0024] Further, the step of determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0 includes:

[0025] When the initial positioning torque is within the predetermined torque difference range from 0, the position corresponding to the initial positioning torque is determined to be the final positioning position, and the electric screwdriver is controlled to move to the final positioning position.

[0026] When the difference between the initial positioning torque and 0 is greater than the maximum value of the predetermined torque difference range, the position adjustment process is entered again, and the first preset direction of the two adjacent position adjustment processes is different.

[0027] Furthermore, the control method further includes:

[0028] The number of times n is entered into the position adjustment process is compared with the maximum limit m;

[0029] When n > m, the positioning of the electric screwdriver is determined to be unsuccessful, and an alarm signal is issued.

[0030] Alternatively, the control method may further include:

[0031] The total time T for entering the position adjustment process is compared with the preset duration T0;

[0032] When T≥T0, the electric screwdriver is judged to have failed to position and an alarm signal is issued.

[0033] Furthermore, after aligning the electric screwdriver with the locking hole, the control method further includes:

[0034] The range of torque applied to the electric screwdriver during the fastening process is determined based on the material of the component to be fastened, the electric screwdriver is controlled to perform fastening operation on the fastening hole, and the torque applied to the electric screwdriver during the fastening operation is obtained.

[0035] If the torque applied to the electric screwdriver exceeds the torque range, it is determined that the electric screwdriver has failed to lock and an alarm signal is issued.

[0036] If the electric screwdriver is applied within the specified torque range and the locking operation is completed, the locking operation is deemed successful, and the locked component is transported from the locking station to the next station.

[0037] Furthermore, when the torque applied to the electric screwdriver is within the specified torque range, the control method further includes:

[0038] Obtain the change in the torque applied to the electric screwdriver;

[0039] When the torque applied to the electric screwdriver increases, the locking torque of the electric screwdriver should be increased accordingly.

[0040] When the torque applied to the electric screwdriver decreases, the locking torque of the electric screwdriver should be reduced accordingly.

[0041] According to another aspect of the present invention, a control system is provided for regulating the fastening process of an electric screwdriver, the control system comprising:

[0042] The acquisition module is configured to: acquire the model number of the component to be locked, determine the set position of the locking hole of the component to be locked on the locking end face according to the model number of the component to be locked, and determine the initial position of the electric screwdriver according to the set position, wherein the initial position is located directly above the set position;

[0043] The control module is configured to: control the electric screwdriver to move downward toward the component to be locked after moving to the initial position, and obtain the positioning torque received by the electric screwdriver during the downward movement;

[0044] The adjustment module is configured to: determine whether the electric screwdriver is positioned relative to the locking hole based on the magnitude of the positioning torque; and, if it is determined that the electric screwdriver is misaligned with the locking hole, enter a position adjustment process to adjust the position of the electric screwdriver relative to the locking hole so that the electric screwdriver is positioned relative to the locking hole.

[0045] Compared to traditional manual or robotic locking with a vision system, the technical solution of this invention also ensures locking accuracy while reducing costs. First, by monitoring and adjusting the torque of the electric screwdriver in real time, high precision and stability of the locking process are ensured, effectively avoiding locking failures caused by incoming material issues and significantly improving assembly efficiency and product quality. Second, this method eliminates the need for an additional vision system, reducing equipment costs and maintenance complexity. Finally, through closed-loop control and torque feedback, this solution can adapt to locking sheet metal parts of different materials, improving the flexibility and adaptability of the production line and providing strong support for the automation upgrade of the manufacturing industry. Attached Figure Description

[0046] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0047] Figure 1 A flowchart illustrating a control method provided according to an embodiment of the present invention is shown;

[0048] Figure 2 A schematic diagram of the overall flow of the control method provided according to an embodiment of the present invention is shown;

[0049] Figure 3 A communication diagram of a control system provided according to an embodiment of the present invention is shown;

[0050] Figure 4 A schematic diagram of a screw fastening mechanism according to an embodiment of the present invention is shown from one perspective.

[0051] Figure 5 A schematic diagram of another perspective of a screw fastening mechanism provided according to an embodiment of the present invention is shown.

[0052] The above figures include the following reference numerals:

[0053] 10. Motor bracket;

[0054] 11. Locking hole;

[0055] 20. Tooling plate;

[0056] 30. Positioning mechanism;

[0057] 40. Electric screwdriver. Detailed Implementation

[0058] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0059] like Figure 1 and 2As shown, Embodiment 1 of the present invention provides a control method for adjusting the fastening process of an electric screwdriver. The control method includes: obtaining the model number of the component to be fastened; determining a set position of the fastening hole of the component to be fastened on the fastening end face based on the model number of the component to be fastened; determining an initial position of the electric screwdriver based on the set position, wherein the initial position is directly above the set position; controlling the electric screwdriver to move downward toward the component to be fastened after moving to the initial position; obtaining the positioning torque received by the electric screwdriver during the downward movement; determining whether the electric screwdriver is aligned with the fastening hole based on the magnitude of the positioning torque; and, if it is determined that the electric screwdriver is misaligned with the fastening hole, entering a position adjustment process to adjust the position of the electric screwdriver relative to the fastening hole so that the electric screwdriver is aligned with the fastening hole.

[0060] By employing the above method, and through real-time monitoring of torque changes at the contact position, the electric screwdriver can be positioned according to torque feedback, ensuring precise fastening. In terms of effectiveness, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of inadequate fastening on product quality. In other embodiments, the accuracy and efficiency of fastening can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during fastening. Furthermore, it also addresses the high cost associated with vision-based fastening.

[0061] Specifically, "the initial position is directly above the set position" can be understood as the initial position being directly above the set position in the vertical direction.

[0062] Specifically, in this embodiment, torque is detected using a high-precision torque sensor. The component to be locked is a motor bracket. Different air conditioner outdoor unit models have corresponding motor brackets. The position of the locking hole is determined during the production of the corresponding motor bracket. However, due to production errors, the determined position of the locking hole may not be the actual position where locking can be performed, and the locking position often needs to be adjusted.

[0063] Specifically, this embodiment ensures that the electric screwdriver can be pre-positioned according to different component models through precise communication between the PLC and the collaborative robot, thereby improving the accuracy of locking. Specifically, the corresponding component to be locked generally has a specific set position, which can be obtained in advance. However, due to production errors, there is often a certain error between the set position and the actual position. The solution of this application can effectively solve the problem of poor locking accuracy caused by production errors.

[0064] In this embodiment, controlling the electric screwdriver to move downwards towards the component to be locked after reaching the initial position, and obtaining the positioning torque experienced by the electric screwdriver during the downward movement, includes: determining the position of the screw-locking point of the electric screwdriver based on a first height difference between the initial position and the set position, wherein a second height difference between the position of the screw-locking point and the set position is greater than the first height difference; controlling the electric screwdriver to move downwards to the position of the screw-locking point, and obtaining the magnitude of the positioning torque experienced by the electric screwdriver during the downward movement to the screw-locking point.

[0065] By precisely controlling the movement path and height of the electric screwdriver, it is ensured that the screwdriver can be tightened at the correct screw-in points, improving tightening accuracy. In principle, real-time monitoring of the torque changes during the downward movement of the electric screwdriver ensures that it tightens at the correct points. In terms of effectiveness, the technology in this embodiment can improve assembly efficiency, reduce labor costs, and avoid the impact of inaccurate tightening positions on product quality. In other embodiments, the tightening accuracy and efficiency can be further improved by optimizing the movement path and speed of the electric screwdriver, solving the problem of unstable screwdriver movement during the tightening process.

[0066] Specifically, determining whether the electric screwdriver is aligned with the locking hole based on the magnitude of the positioning torque includes: obtaining the maximum value of the positioning torque of the electric screwdriver during its downward movement to the screw-locking point as a first torque; comparing the first torque with a first preset torque; determining that the electric screwdriver is misaligned with the locking hole if the first torque is greater than the first preset torque; and determining that the electric screwdriver is aligned with the locking hole if the first torque is less than or equal to the first preset torque.

[0067] This embodiment accurately determines whether the electric screwdriver is aligned with the locking hole by comparing the maximum value of the positioning torque with the preset torque, thus improving locking accuracy. In principle, a torque sensor monitors the torque change of the electric screwdriver in real time during its downward movement, ensuring that the screwdriver locks at the correct position. In terms of effectiveness, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of inaccurate locking position on product quality. In other embodiments, the locking accuracy and efficiency can be further improved by adjusting the preset torque, solving the problem of inaccurate electric screwdriver positioning during the locking process.

[0068] In this embodiment, the position adjustment process for adjusting the position of the electric screwdriver relative to the locking hole includes: controlling the electric screwdriver to move from the locking screw point to a first preset position along a first preset direction on the radial plane of the locking hole, and obtaining the minimum value of the positioning torque experienced by the electric screwdriver during the movement to the first preset position as a second torque; comparing the second torque with the first torque, where the first torque is the maximum value of the positioning torque during the downward movement of the electric screwdriver; when the second torque is greater than or equal to the first torque, determining that the movement direction of the electric screwdriver is incorrect, and controlling the electric screwdriver to return to the locking screw point; when the second torque is less than the first torque, determining that the movement direction of the electric screwdriver is correct, determining the second torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the first preset position and the locking screw point is greater than or equal to the production error of the locking hole.

[0069] This embodiment, by controlling the movement of the electric screwdriver in the radial plane and monitoring torque changes in real time, can accurately determine whether the movement direction of the electric screwdriver is correct, thus improving the fastening accuracy. In principle, using a torque sensor to monitor the torque changes of the electric screwdriver during its movement ensures that the electric screwdriver fastens at the correct position. In terms of effectiveness, the technology in this embodiment can improve assembly efficiency, reduce labor costs, and avoid the impact of inaccurate fastening positions on product quality. In other embodiments, the fastening accuracy and efficiency can be further improved by optimizing the movement path and speed of the electric screwdriver, solving the problem of unstable movement of the electric screwdriver during the fastening process.

[0070] In this embodiment, after controlling the electric screwdriver to return to the screw locking position, the control method further includes: controlling the electric screwdriver to move along a second preset direction opposite to the first preset direction to a second preset position, and obtaining the minimum value of the positioning torque received by the electric screwdriver when it moves to the second preset position as a third torque, determining the third torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the second preset position and the screw locking position is greater than or equal to the production error of the locking hole.

[0071] This embodiment, by controlling the electric screwdriver to move in the opposite direction and monitoring torque changes in real time, can further determine whether the electric screwdriver's positioning is accurate, thus improving the fastening precision. In principle, using a torque sensor to monitor the torque changes of the electric screwdriver during its movement ensures that the screwdriver fastens at the correct point. In terms of effect, the technology in this embodiment can improve assembly efficiency, reduce labor costs, and avoid the impact of inaccurate fastening positioning on product quality. In other embodiments, the fastening precision and efficiency can be further improved by optimizing the electric screwdriver's movement path and speed, solving the problem of inaccurate electric screwdriver positioning during the fastening process.

[0072] Specifically, determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0 includes: when the initial positioning torque and 0 are within a predetermined torque difference range, determining that the position corresponding to the initial positioning torque is the final positioning position, and controlling the electric screwdriver to move to the final positioning position; when the difference between the initial positioning torque and 0 is greater than the maximum value of the predetermined torque difference range, re-entering the position adjustment process, and making the first preset direction different for the two adjacent position adjustment processes.

[0073] This embodiment accurately determines whether the electric screwdriver has been positioned to its final location by comparing the difference between the initial positioning torque and zero, thus improving the fastening accuracy. In principle, a torque sensor monitors the torque change of the electric screwdriver in real time during its movement, ensuring that the screwdriver fastens at the correct point. In terms of effectiveness, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of inaccurate fastening positions on product quality. In other embodiments, the accuracy and efficiency of fastening can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during the fastening process.

[0074] In this embodiment, the control method further includes: comparing the number of times n enters the position adjustment process with the maximum limited number m; when n > m, determining that the electric screwdriver has failed to position and issuing an alarm signal; or, the control method further includes: comparing the total time T for entering the position adjustment process with a preset duration T0; when T ≥ T0, determining that the electric screwdriver has failed to position and issuing an alarm signal.

[0075] This embodiment effectively prevents electric screwdriver positioning failures and improves locking accuracy by setting limits on the number of times and time for position adjustment. In principle, a torque sensor monitors the torque changes of the electric screwdriver in real time during its movement, ensuring that the screwdriver locks at the correct position. In terms of effect, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of inaccurate locking positions on product quality. In other embodiments, the accuracy and efficiency of locking can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during the locking process.

[0076] Specifically, after the electric screwdriver is positioned opposite the locking hole, the control method further includes: determining the range of torque applied to the electric screwdriver during the locking process based on the material of the component to be locked; controlling the electric screwdriver to perform the locking operation on the locking hole; and acquiring the torque applied to the electric screwdriver during the locking operation; if the torque applied to the electric screwdriver exceeds the torque range, determining that the locking operation has failed and issuing an alarm signal; if the torque applied to the electric screwdriver is within the torque range and the locking operation is completed, determining that the locking operation has succeeded, and transporting the component to be locked from the locking station to the next station.

[0077] This embodiment determines the torque range of the electric screwdriver based on the component material, accurately judging whether the screwdriver fastening is successful and improving fastening accuracy. In principle, a torque sensor monitors the torque change of the electric screwdriver in real time during the fastening process, ensuring that the screwdriver fastens within the correct torque range. In terms of effect, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of improper fastening torque on product quality. In other embodiments, the accuracy and efficiency of fastening can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during the fastening process.

[0078] In this embodiment, when the torque applied to the electric screwdriver is within the specified torque range, the control method further includes: acquiring the change in the torque applied to the electric screwdriver; increasing the locking torque of the electric screwdriver when the torque applied to the electric screwdriver increases; and decreasing the locking torque of the electric screwdriver when the torque applied to the electric screwdriver decreases.

[0079] This embodiment monitors the changes in the torque applied to the electric screwdriver in real time and adjusts the locking torque accordingly, ensuring more precise torque control during the locking process and improving locking accuracy. In principle, using a torque sensor to monitor the torque changes of the electric screwdriver in real time ensures that the screwdriver locks within the correct torque range. In terms of effectiveness, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of improper locking torque on product quality. In other embodiments, the accuracy and efficiency of locking can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during the locking process.

[0080] This embodiment effectively prevents electric screwdriver positioning failures and improves locking accuracy by setting limits on the number of times and time for position adjustment. In principle, a torque sensor monitors the torque changes of the electric screwdriver in real time during its movement, ensuring that the screwdriver locks at the correct position. In terms of effect, the technology in this embodiment improves assembly efficiency, reduces labor costs, and avoids the impact of inaccurate locking positions on product quality. In other embodiments, the accuracy and efficiency of locking can be further improved by optimizing the accuracy and response speed of the torque sensor, solving the problem of untimely torque feedback during the locking process.

[0081] First, the PLC selects the machine model and sends character "A" to the collaborative robot. The robot receives "A" and returns to its initial position. After returning to the initial position, it sends character "B" to the PLC to indicate that the robot has returned to a safe position and is ready to perform the locking operation once the product is positioned. After the product is in place, a positioning mechanism lifts and positions the tooling plate carrying the product, separating it from the production line. After separation, the linear module extends to position the motor bracket, ensuring it is flush with the sheet metal part to prevent one hole from lifting while locking another. After positioning, character "C" is sent to the robot to indicate permission to lock. The robot receives "C" and performs the locking operation. The robot moves above the locking position and then moves to the locking position in torque mode. It reads the torque change from the torque sensor in the two-dimensional plane of the locking position and moves to the locking point within a given range of torque parameters, constantly monitoring the torque value between the electric screwdriver and the contact position and direction. After locking is complete, the PLC sends character "E" to the collaborative robot, which receives "E" and immediately returns to its safe position. Simultaneously, the linear module fixing the motor bracket returns to its initial position. After all modules have returned to their initial positions, the positioning mechanism on the production line descends, the line stops and releases, and the product flows away. The next outdoor unit then repeats the process. During the fastening process, by monitoring the changes in the torque of the electric screwdriver in real time, more precise torque control can be ensured, improving fastening accuracy. Furthermore, by setting the number of times and time limits for the position adjustment process, positioning failure of the electric screwdriver can be effectively prevented, further improving fastening accuracy.

[0082] Another embodiment of the present invention provides a control system for adjusting the fastening process of an electric screwdriver. The control system includes: an acquisition module configured to: acquire the model number of the component to be fastened; determine a set position of the fastening hole of the component to be fastened on the fastening end face based on the model number of the component to be fastened; and determine an initial position of the electric screwdriver based on the set position, wherein the initial position is directly above the set position; a control module configured to: control the electric screwdriver to move downward toward the component to be fastened after moving to the initial position; and acquire the positioning torque experienced by the electric screwdriver during the downward movement; and an adjustment module configured to: determine whether the electric screwdriver is positioned relative to the fastening hole based on the magnitude of the positioning torque; and, if it is determined that the electric screwdriver is misaligned with the fastening hole, enter a position adjustment process to adjust the position of the electric screwdriver relative to the fastening hole so that the electric screwdriver is positioned relative to the fastening hole.

[0083] By cooperating with PLCs and collaborative robots, the system achieves automatic material feeding, automatic translation of torque values ​​for precise positioning, and continuous acquisition of torque changes from torque sensors to achieve precise locking.

[0084] During the pre-production debugging phase, the torque changes (Z-direction, i.e., height direction) of the electric screwdriver servo current loop parameters (current loop parameters are basic hardware-related parameters of the servo system) for locking two different sheet metal parts are first collected. These torque changes are then converted into data for automatic locking. During the automatic locking process, this torque change data from the debugging phase is used to achieve closed-loop control. For example, the data collected during the debugging phase shows that the torque is very small, almost zero, when the screw passes through the through hole without touching the second sheet metal part. When it touches the second sheet metal part, the torque increases to 3N, stabilizing at 2N after thread feeding. During control, if the torque feedback value when touching the second sheet metal part is greater than 3N, the locking torque is increased appropriately; if the torque feedback value is less than 3N, the locking torque is decreased appropriately.

[0085] like Figure 3 As shown, Modbus communication is used during the production process to achieve communication between the robot and the PLC, with the PLC acting as the server and the robot as the client. First, the production model is selected on the touchscreen (during debugging, the predetermined positioning position for each production model is written into the touchscreen, PLC, and robot programs). After starting the equipment, character A is sent to the robot. The robot receives character A and returns to its initial position. After returning to the initial position, it sends character B to the PLC to indicate that the robot has returned to the safe position. Once the product is positioned, the locking operation can be performed immediately. For example... Figure 4 As shown, after the product is in place, the positioning mechanism 30 lifts and positions the tooling plate 20 carrying the product, separating the tooling plate 20 from the production line. After separation, the linear module extends out to... Figure 5 The motor bracket 10 shown is positioned to ensure it is in close contact with the sheet metal part, preventing one locking hole 11 from lifting up when locking one locking hole 11. After positioning, the character "C" is sent to the robot to indicate permission to lock. Upon receiving "C", the robot drives the electric screwdriver 40 to perform the locking operation. The robot moves above the locking position, then moves to the locking position in torque mode, and reads the locking position (e.g., ...). Figure 5The tooling plate 20 has a planar orientation including mutually perpendicular X and Y directions, and the Z direction is perpendicular to both X and Y directions. The torque sensor in the two-dimensional plane monitors torque changes and moves to the locking point (corresponding to the locking position) within a given range of torque parameters. The robot continuously monitors the torque value of the electric screwdriver at the contact position and in the direction of contact. Simultaneously, the collaborative robot adjusts its direction and force based on feedback from the torque sensor. (For example, during movement to the locking position, if the torque in the X+ direction is greater than the set torque, and the torque in the X- direction is closer to the set torque than in the X+ direction, the robot will shift towards the X- direction; the same applies to each direction in the two-dimensional plane of the locking position.) This ensures accurate movement to the locking position of each product. If the torque value still exceeds the given range within a certain time, it indicates that the corresponding locking hole cannot be found, and an alarm will alert on-site personnel. If the robot successfully moves to the product's locking position, it will send the character "D" to the PLC, indicating successful movement to the locking position. The PLC receives the character "D" from the collaborative robot and begins driving the electric screwdriver to perform the screw-locking operation. During the automatic locking process, closed-loop control is achieved by combining torque changes collected during the commissioning phase (as described above). After locking is completed, the PLC sends the character "E" to the collaborative robot. Upon receiving "E," the collaborative robot immediately returns to the safe position. Simultaneously, the linear module fixing the motor bracket also returns to its initial position. After all components have returned to their initial positions, the positioning mechanism on the production line descends, the line is blocked and released, and the product flows away. The next external machine then repeats the process.

[0086] From the above description, it can be seen that the embodiments of the present invention achieve the following technical effects: During the process of fixing the motor bracket, the torque change at the contact position between the electric screwdriver at the end of the robot flange and the outdoor unit is monitored in real time to ensure that the motor bracket is accurately locked onto the outdoor unit chassis. When locking two sheet metals of different materials, the torque magnitudes fed back by the two different sheet metals are collected, and the locking torque is controlled through real-time torque feedback during production to achieve successful locking. This solves the problems of low efficiency in manual assembly and high cost of industrial robots with vision systems. The present invention corrects locking failures caused by incoming material issues. The present invention can solve the problem of easy locking failures when locking two sheet metals of different materials; improves assembly efficiency and reduces labor costs. It improves assembly accuracy to eliminate the impact of inadequate fixing on subsequent workstations and product quality.

[0087] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0088] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0089] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0090] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0091] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method, characterized in that, The control method is used to regulate the fastening process of the electric screwdriver, and the control method includes: Obtain the model number of the component to be locked, determine the set position of the locking hole of the component to be locked on the locking end face according to the model number of the component to be locked, determine the initial position of the electric screwdriver according to the set position, and the initial position is located directly above the set position; After the electric screwdriver is moved to the initial position, it moves downward toward the component to be locked, and the positioning torque received by the electric screwdriver during the downward movement is obtained. The magnitude of the positioning torque determines whether the electric screwdriver is positioned relative to the locking hole; and if it is determined that the electric screwdriver is misaligned with the locking hole, a position adjustment process is initiated to adjust the position of the electric screwdriver relative to the locking hole so that the electric screwdriver is positioned relative to the locking hole. The position adjustment process for adjusting the position of the electric screwdriver relative to the locking hole includes: controlling the electric screwdriver to move from the screw-locking point to a first preset position along a first preset direction on the radial plane of the locking hole, and obtaining the minimum value of the positioning torque experienced by the electric screwdriver during the movement to the first preset position as a second torque; comparing the second torque with the first torque, where the first torque is the maximum value of the positioning torque experienced by the electric screwdriver during the downward movement; when the second torque is greater than or equal to the first torque, determining that the movement direction of the electric screwdriver is incorrect, and controlling the electric screwdriver to return to the screw-locking point; when the second torque is less than the first torque, determining that the movement direction of the electric screwdriver is correct, determining the second torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the first preset position and the screw-locking point is greater than or equal to the production error of the locking hole; when controlling the electric screwdriver to return to the first preset position... After determining the screw location, the control method further includes: controlling the electric screwdriver to move along a second preset direction opposite to the first preset direction to a second preset position, and obtaining the minimum value of the positioning torque received by the electric screwdriver when it moves to the second preset position as a third torque, determining the third torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the second preset position and the screw location is greater than or equal to the production error of the locking hole; the determination of whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0 includes: when the initial positioning torque and 0 are within a predetermined torque difference range, determining that the position corresponding to the initial positioning torque is the final positioning position, and controlling the electric screwdriver to move to the final positioning position; when the difference between the initial positioning torque and 0 is greater than the maximum value of the predetermined torque difference range, re-entering the position adjustment process, and making the first preset direction different for adjacent position adjustment processes.

2. The control method according to claim 1, characterized in that, The step of controlling the electric screwdriver to move downwards towards the component to be locked after it has reached the initial position, and obtaining the positioning torque experienced by the electric screwdriver during the downward movement, includes: The position of the screw-locking point of the electric screwdriver is determined based on the first height difference between the initial position and the set position, and the second height difference between the position of the screw-locking point and the set position is greater than the first height difference; The electric screwdriver is controlled to move downwards to the screw-locking point, and the positioning torque of the electric screwdriver during the downward movement to the screw-locking point is obtained.

3. The control method according to claim 2, characterized in that, The step of determining whether the electric screwdriver is aligned with the locking hole based on the magnitude of the positioning torque includes: The maximum value of the positioning torque of the electric screwdriver during its downward movement to the screw-locking point is obtained as the first torque, and the first torque is compared with the first preset torque. If the first torque is greater than the first preset torque, it is determined that the electric screwdriver and the locking hole are misaligned. If the first torque is less than or equal to the first preset torque, it is determined that the electric screwdriver is positioned opposite to the locking hole.

4. The control method according to claim 1, characterized in that, The control method further includes: The number of times n is entered into the position adjustment process is compared with the maximum limit m; When n > m, the positioning of the electric screwdriver is determined to be unsuccessful, and an alarm signal is issued. Alternatively, the control method may further include: The total time T for entering the position adjustment process is compared with the preset duration T0; When T≥T0, the electric screwdriver is judged to have failed to position and an alarm signal is issued.

5. The control method according to claim 1, characterized in that, After the electric screwdriver is positioned opposite the locking hole, the control method further includes: The range of torque applied to the electric screwdriver during the fastening process is determined based on the material of the component to be fastened, the electric screwdriver is controlled to perform fastening operation on the fastening hole, and the torque applied to the electric screwdriver during the fastening operation is obtained. If the torque applied to the electric screwdriver exceeds the torque range, it is determined that the electric screwdriver has failed to lock and an alarm signal is issued. If the electric screwdriver is applied within the specified torque range and the locking operation is completed, the locking operation is deemed successful, and the locked component is transported from the locking station to the next station.

6. The control method according to claim 5, characterized in that, When the torque applied to the electric screwdriver is within the specified torque range, the control method further includes: Obtain the change in the torque applied to the electric screwdriver; When the torque applied to the electric screwdriver increases, the locking torque of the electric screwdriver should be increased accordingly. When the torque applied to the electric screwdriver decreases, the locking torque of the electric screwdriver should be reduced accordingly.

7. A control system, characterized in that, The control system is used to regulate the fastening process of the electric screwdriver, and the control system includes: The acquisition module is configured to: acquire the model number of the component to be locked, determine the set position of the locking hole of the component to be locked on the locking end face according to the model number of the component to be locked, and determine the initial position of the electric screwdriver according to the set position, wherein the initial position is located directly above the set position; The control module is configured to: control the electric screwdriver to move downward toward the component to be locked after moving to the initial position, and obtain the positioning torque received by the electric screwdriver during the downward movement; The adjustment module is configured to: determine whether the electric screwdriver is positioned relative to the locking hole based on the magnitude of the positioning torque; and, if it is determined that the electric screwdriver is misaligned with the locking hole, enter a position adjustment process to adjust the position of the electric screwdriver relative to the locking hole so that the electric screwdriver is positioned relative to the locking hole. The position adjustment process for adjusting the position of the electric screwdriver relative to the locking hole includes: controlling the electric screwdriver to move from the screw-locking point to a first preset position along a first preset direction on the radial plane of the locking hole, and obtaining the minimum value of the positioning torque experienced by the electric screwdriver during the movement to the first preset position as a second torque; comparing the second torque with the first torque, where the first torque is the maximum value of the positioning torque experienced by the electric screwdriver during the downward movement; when the second torque is greater than or equal to the first torque, determining that the movement direction of the electric screwdriver is incorrect, and controlling the electric screwdriver to return to the screw-locking point; when the second torque is less than the first torque, determining that the movement direction of the electric screwdriver is correct, determining the second torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the first preset position and the screw-locking point is greater than or equal to the production error of the locking hole; when controlling the electric screwdriver to return to the first preset position... After determining the screw location, the control method further includes: controlling the electric screwdriver to move along a second preset direction opposite to the first preset direction to a second preset position, and obtaining the minimum value of the positioning torque received by the electric screwdriver when it moves to the second preset position as a third torque, determining the third torque as the initial positioning torque, and determining whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0; wherein, the position difference between the second preset position and the screw location is greater than or equal to the production error of the locking hole; the determination of whether to re-enter the position adjustment process based on the comparison between the initial positioning torque and 0 includes: when the initial positioning torque and 0 are within a predetermined torque difference range, determining that the position corresponding to the initial positioning torque is the final positioning position, and controlling the electric screwdriver to move to the final positioning position; when the difference between the initial positioning torque and 0 is greater than the maximum value of the predetermined torque difference range, re-entering the position adjustment process, and making the first preset direction different for adjacent position adjustment processes.

Images