Continuous production line seam detection method
By working in tandem with a laser rangefinder and a control system, non-contact inspection of aluminum seams is achieved, solving the problems of high equipment cost, difficult maintenance, and poor product quality associated with traditional punching and shearing inspection. This improves production efficiency and yield, and is particularly suitable for aluminum production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-15
- Publication Date
- 2026-03-31
AI Technical Summary
Traditional methods for inspecting seams have problems such as high equipment costs, difficult maintenance, low yield, and low production efficiency. In particular, in aluminum production, punching and shearing inspections can lead to waste residue and aluminum dross adhesion, which affects the quality of finished products.
The system employs a laser rangefinder and control system to work together to detect the thickness of the strip in real time. It accurately locates the seam opening through a non-contact method, enabling the pressure roller to automatically lift and drop. This avoids the formation of seam holes during punching and shearing, reducing equipment maintenance difficulty and improving the surface quality of the finished product.
It enables efficient and accurate detection of aluminum seams, reduces equipment costs and maintenance difficulty, and improves yield and production efficiency. It is suitable for the production of aluminum materials that are either ultra-hard or soft.
Smart Images
Figure CN121761776A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of aluminum seam inspection technology, and in particular to a method for inspecting seams on a continuous production line. Background Technology
[0002] In the production of aluminum profiles, two aluminum coils are typically joined together using an overlapping and stitching process; the joint is called the seam. During production, when the seam passes over a rubber roller, its thickness and openness can damage the roller's surface, affecting the surface quality of the finished product. Therefore, positioning the seam and implementing automatic roller lifting and avoidance functions in the equipment is crucial.
[0003] The traditional method for inspecting suture openings involves using a punch cutter to manually create a circular suture hole (4) during the suturing process. Figure 1 and Figure 2 As shown, the through-beam switch is then used to inspect the suture hole 4. Using a punching and shearing method will lead to the following problems:
[0004] During punching and shearing, some scrap material is not completely separated, and part of it remains connected to the strip, making it difficult to remove.
[0005] Aluminum dross is easily generated during punching and shearing, which tends to stick to the rollers and affects the surface quality of the finished product.
[0006] Manual punching is required, which increases the difficulty of operation.
[0007] It is evident that the method of inspecting the seam opening by punching and shearing has many shortcomings, which significantly increases equipment costs and maintenance difficulty, and affects the yield and production efficiency. Summary of the Invention
[0008] The purpose of this application is to provide a method for detecting seam openings on a continuous production line. This method replaces the traditional punching and shearing method for detecting seam openings, reduces equipment costs and maintenance difficulty, increases yield, and improves production efficiency.
[0009] To achieve the above objectives, this application provides a method for detecting seam openings in a continuous production line, comprising:
[0010] A laser rangefinder is installed at a fixed position in front of the tensioning roller, and the laser rangefinder is connected to the control system.
[0011] The distance X between the tensioning roller surface and the laser rangefinder is detected in real time.
[0012] The control system calculates the thickness T of the strip on the tensioning roller based on the difference between the maximum detection distance L and the current detection distance X, where T = LX.
[0013] Optionally, if there is no strip on the tensioning roller, the current detection distance X is equal to the maximum distance L, and the calculated plate thickness T=0.
[0014] Optionally, when a regular strip passes over the tensioning roller, the current detection distance X = L - T1, where T1 is the thickness of the previous rolled strip, and the calculated strip thickness T = T1.
[0015] Optionally, when the tensioning roller passes through the seam, the current detection distance X = L - T1 - T2 - T3, where T1 is the thickness of the front rolled strip, T2 is the thickness of the rear rolled strip, T3 is the thickness of the threading strip, and the calculated plate thickness T = T1 + T2 + T3.
[0016] Optionally, the threading strip is fixedly disposed at the tail end of the front roll of strip and the head end of the rear roll of strip, and is located at the joint surface between the front roll of strip and the rear roll of strip, for fixing the two independent rolls of strip together.
[0017] Optionally, installing the laser rangefinder includes adjusting the installation angle of the laser rangefinder so that the laser emitted by it is perpendicular to the tangent of the tension roller surface.
[0018] Optionally, the control system is used to receive the distance signal detected by the laser rangefinder and calculate the plate thickness according to a preset algorithm; the control system is connected to the laser rangefinder and the PLC to realize data interaction and command issuance.
[0019] Optionally, it also includes establishing a strip thickness detection database to store historical data such as the maximum detection distance L, the current detection distance X, and the calculated strip thickness T.
[0020] Optionally, it also includes:
[0021] When a sudden change in plate thickness is detected, the suture identification algorithm is automatically triggered to distinguish between ordinary plate strips and sutures.
[0022] The suture identification algorithm includes: the calculated thickness T rapidly jumps from one stable value to another stable value, and after maintaining this value for a preset time, it falls back to the previous stable value.
[0023] Optionally, the system also includes setting an alarm threshold for abnormal plate thickness, comparing the calculated plate thickness T with a preset thickness, and automatically issuing an alarm signal when the calculated plate thickness T is higher or lower than the preset range.
[0024] The beneficial effects of this application are that, through the coordinated operation of the laser rangefinder and the control system, real-time, non-contact detection of the sheet thickness is achieved. Depending on the detected thickness, the seam opening can be accurately located, and the pressure roller can be automatically raised and lowered, with the equipment automatically avoiding obstacles. The laser rangefinder uses a non-contact measurement method, effectively avoiding seam holes caused by punching and shearing, ensuring that the appearance and performance of the half-bag are not affected. This solves the problem of difficult maintenance of punching and shearing, and also solves the problem of aluminum slag generated by punching and shearing affecting the surface quality of the finished product. It is especially suitable for ultra-hard, thin materials (such as stainless steel, copper, and aluminum plates) or soft, easily deformable materials (such as plastic and rubber sheets). Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0026] Figure 1 This is a schematic diagram of the structure of the punching and shearing detection suture in the prior art;
[0027] Figure 2 for Figure 1 A sectional view;
[0028] Figure 3 This is a schematic diagram of the first scenario of the continuous production line seam detection method provided in the embodiments of this application;
[0029] Figure 4 This is a schematic diagram of the second case of the continuous production line seam detection method provided in the embodiments of this application;
[0030] Figure 5 This is a schematic diagram of the third case of the continuous production line seam detection method provided in the embodiments of this application.
[0031] In the diagram: 1-front winding strip; 2-rear winding strip; 3-threading strip; 4-sewing hole; 5-laser rangefinder; 6-tensioning roller. Detailed Implementation
[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0033] It should be noted that in this embodiment, the orientation or positional relationship indicated by terms such as "upper," "lower," "front," and "rear" is based on the orientation or positional relationship shown in the accompanying drawings. It is used only for the convenience of describing this application and for simplifying the description, and does 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. Therefore, it should not be construed as a limitation of this application. Furthermore, "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0034] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0035] In this embodiment, a method for detecting seam openings on a continuous production line is provided, the method comprising:
[0036] Install a laser rangefinder 5 at a fixed position in front of the tension roller 6. The installation position should be free from vibration, and the laser rangefinder 5 should not shake.
[0037] The distance X between the tension roller 6 and the surface of the tension roller 6 is detected in real time by the laser rangefinder 5. The laser rangefinder technology itself has high measurement accuracy. Combined with the fixed installation position and stable reference benchmark, the accuracy of the thickness calculation results is ensured. The laser detection method avoids direct contact with the material, so it will not affect the production process or cause wear or damage to the equipment or products.
[0038] The control system calculates the thickness T of the strip on the tension roller 6 based on the difference between the maximum detection distance L and the current detection distance X, where T = LX; and determines the specific situation of the strip passing on the tension roller 6 at this time by using the difference between the maximum detection distance L and the current detection distance X.
[0039] Please refer to Figure 3 When there is no strip on tension roller 6, the current detection distance X equals the maximum distance L, and the calculated plate thickness T=0; please refer to... Figure 4 When a regular strip passes over the tension roller 6, typically the front-coiled strip 1, the current detection distance X = L - T1, where T1 is the thickness of the front-coiled strip 1. The thickness T is calculated as T = T1. Please refer to... Figure 5 When the tension roller 6 passes through the seam, the current detection distance X = L - T1 - T2 - T3, where T1 is the thickness of the front rolled strip 1, T2 is the thickness of the rear rolled strip 2, and T3 is the thickness of the threading strip 3. The calculated plate thickness T = T1 + T2 + T3.
[0040] As can be seen, this application achieves real-time, non-contact detection of the thickness of the strip by coordinating the laser rangefinder 5 with the control system. Depending on the detected thickness, the seam opening can be accurately located, and the pressure roller can be automatically raised and lowered, with the equipment automatically avoiding obstacles. The laser rangefinder 5 uses a non-contact measurement method, which effectively avoids the seam hole 4 caused by punching and shearing, ensuring that the appearance and performance of the half-bag are not affected. This solves the problem of difficult maintenance of punching and shearing, and also solves the problem of aluminum slag from punching and shearing affecting the surface quality of the finished product. It is especially suitable for ultra-hard, thin materials (such as stainless steel, copper, and aluminum plates) or soft, easily deformable materials (such as plastic and rubber sheets).
[0041] Further, please refer to Figure 1 and Figure 2 The connection method of the front coiled strip 1, the rear coiled strip 2 and the threading strip 3 is the same as that of the prior art. The strip is fixedly set at the tail of the front coiled strip 1 and the head of the rear coiled strip 2, and is located at the joint surface between the front coiled strip 1 and the rear coiled strip 2, for fixing the two independent strips together.
[0042] In some embodiments, when installing the laser rangefinder 5, the installation angle of the laser rangefinder 5 should be adjusted so that the laser emitted is perpendicular to the tangent of the tension roller 6. When the laser beam is perpendicular to the tangent of the roller surface, the reflected light can return to the receiving end of the laser rangefinder 5 to the maximum extent, ensuring maximum signal strength. This effectively avoids the signal attenuation problem caused by excessive incident angle, thereby improving the accuracy of strip thickness measurement.
[0043] In addition, vertically incident laser beams are less affected by ambient light interference, and background light usually does not superimpose with the vertically reflected laser signal, which helps to maintain stable measurement performance under complex lighting conditions.
[0044] The control system is used to receive the distance signal detected by the laser rangefinder 5 and calculate the plate thickness according to the preset algorithm. By directly receiving the real-time distance signal from the laser rangefinder 5 and calculating the plate thickness based on the preset algorithm, the control system realizes the automated processing from data acquisition to thickness calculation.
[0045] Meanwhile, the control system is connected to the laser rangefinder 5 and the PLC to realize data interaction and command issuance, so that the calculated thickness data can be directly transmitted to the PLC for subsequent process adjustment or equipment control, forming a complete closed loop of "detection-calculation-control".
[0046] To facilitate the standardized inspection of different batches of strip, this method also includes establishing a strip thickness inspection database. This database can store historical data such as the maximum inspection distance L, the current inspection distance X, and the calculated strip thickness T, allowing for complete traceability of the production quality of each batch of strip and providing data support for process improvement. For example, when an abnormality in the strip thickness of a certain batch is detected, the database can be used to quickly locate the corresponding production time, equipment parameters, and other key information, assisting in root cause analysis of quality issues.
[0047] In addition, the long-accumulated database can analyze the thickness distribution pattern of the plate under different process parameters, providing data support for plate and strip thickness parameters, optimization of seam treatment, etc.
[0048] In some embodiments, to ensure the accuracy of suture detection, the method also introduces a suture recognition algorithm; specifically, when a sudden change in plate thickness is detected, the suture recognition algorithm is automatically triggered to distinguish between ordinary plate strips and sutures. The suture recognition algorithm includes calculating the thickness T, which rapidly jumps from one stable value to another, and after maintaining this for a preset time, falls back to the previous stable value.
[0049] This algorithm accurately captures the unique "rapid rise-hold-fall" thickness abrupt change pattern at the seam by monitoring the stable changes in the plate thickness T in real time. This identification method can effectively distinguish between ordinary plate strips and seams, avoiding misjudging normal thickness fluctuations or abnormal plate strip protrusions as defects, while ensuring high sensitivity detection of seams. Furthermore, by recording the time points and specific parameters of the aforementioned thickness abrupt changes (such as rise amplitude and holding time), data support can be provided for process optimization.
[0050] It should be noted that when a sudden change in thickness occurs in this embodiment, the detected thickness T will jump from T1 to T1+T2+T3 within a certain period of time. At this time, it indicates that the laser rangefinder 5 has detected the seam opening. If the detected thickness T remains at T1+T2+T3 for a certain period of time in the future, it is determined that the seam opening is passing through the tension roller 6.
[0051] Furthermore, if the detected thickness T decreases from T1+T2+T3 to T1 within a certain period of time, and the detected thickness T remains at T1 for a subsequent period of time, it indicates that the seam has passed through the tension roller 6.
[0052] The method also includes setting an alarm threshold for abnormal plate thickness. By automatically comparing the real-time calculated plate thickness T with a preset range, the control system can immediately identify thickness anomalies (such as being too high or too low) and trigger an alarm signal. This real-time monitoring mechanism allows operators to quickly detect quality problems in the production process, preventing defective products from flowing into subsequent processes, thereby reducing material waste and rework costs.
[0053] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.
[0054] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.
Claims
1. A method for detecting seam openings in a continuous production line, characterized in that, include: A laser rangefinder (5) is installed at a fixed position in front of the tension roller (6), and the laser rangefinder (5) is connected to the control system; The distance X of the tension roller (6) surface is detected in real time by the laser rangefinder (5); The control system calculates the thickness T of the strip on the tension roller (6) based on the difference between the maximum detection distance L and the current detection distance X, where T = LX.
2. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, When there is no strip on the tensioning roller (6), the current detection distance X is equal to the maximum distance L, and the calculated plate thickness T=0.
3. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, When ordinary strip passes through the tension roller (6), the current detection distance X = L - T1, where T1 is the thickness of the front rolled strip (1), and the calculated thickness T = T1.
4. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, When the tensioning roller (6) passes through the seam, the current detection distance X = L - T1 - T2 - T3, where T1 is the thickness of the front rolled strip (1), T2 is the thickness of the rear rolled strip (2), T3 is the thickness of the threading strip (3), and the plate thickness T = T1 + T2 + T3 is calculated.
5. The method for detecting seam openings in a continuous production line according to claim 4, characterized in that, The threading strip (3) is fixedly installed at the tail of the front roll strip (1) and the head of the rear roll strip (2), and is located at the joint surface between the front roll strip (1) and the rear roll strip (2), for fixing the two independent roll strips together.
6. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, Installing the laser rangefinder (5) includes: adjusting the installation angle of the laser rangefinder (5) so that the laser emitted by it is perpendicular to the tangent of the tension roller (6).
7. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, The control system is used to receive the distance signal detected by the laser rangefinder (5) and calculate the plate thickness according to the preset algorithm; the control system is connected to the laser rangefinder (5) and the PLC to realize data interaction and command issuance.
8. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, It also includes establishing a plate and strip thickness detection database to store historical data such as the maximum detection distance L, the current detection distance X, and the calculated plate thickness T.
9. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, Also includes: When a sudden change in plate thickness is detected, the suture identification algorithm is automatically triggered to distinguish between ordinary plate strips and sutures. The suture identification algorithm includes: the calculated thickness T rapidly jumps from one stable value to another stable value, and after maintaining this value for a preset time, it falls back to the previous stable value.
10. The method for detecting seam openings in a continuous production line according to claim 1, characterized in that, It also includes setting an alarm threshold for abnormal plate thickness, comparing the calculated plate thickness T with a preset thickness, and when the calculated plate thickness T is higher or lower than the preset range, the control system automatically issues an alarm signal.