Carton forming method

Abstract

The invention relates to the technical field of carton manufacturing, and discloses a carton forming method which comprises the following steps: paperboard information acquisition and positioning: feeding a pre-cut corrugated paperboard into a forming area, acquiring thickness and moisture content of the corrugated paperboard and temperature and humidity information of a field environment, and positioning paperboard edge and indentation data based on image recognition; and parameter-driven folding operation is conducted, specifically, a multi-point linkage servo folding mechanism is controlled to execute folding based on the paperboard edge and indentation data, the folding angle is 80-100 degrees, the folding pressure is 30-60 N, the folding speed is 100-300 mm / s, and meanwhile periodic feedback correction is conducted in the folding process. By optimizing the formula of the adhesive, adjusting the sizing process and accurately controlling the spraying parameters, the adhesive strength of the carton is improved, the sizing uniformity is enhanced, the folding precision is improved, the appearance consistency is improved, and the structural stability and the production quality of the carton are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of carton manufacturing, in particular to a carton forming method. BACKGROUND

[0002] As the core carrier of commodity packaging and transportation, the structural strength and forming quality of the carton directly affect the transportation safety and user experience of the product; especially in the scene that needs to be repeatedly stacked, transported or stored for a long time, when the carton structure is unstable and the joint is not firm, it is easy to deform and damage, and also easy to cause damage to the goods during transportation.

[0003] In the prior art, starch or vinyl acetate adhesives are often used in combination with hot melt spraying process for paperboard bonding; the prior art scheme has simple bonding process and low cost, and is suitable for mass production. At the same time, part of the modified glue also has certain moisture resistance, which can maintain the basic paperboard adhesion effect in the conventional environment. In addition, part of the existing production line controls the folding track by mechanical control, so that the preliminary forming of the carton has certain neatness and size consistency.

[0004] But the adhesives in the prior art are mostly single-component, with limited bonding force, and the carton often cracks at the joint during transportation, durability; the flowability is often insufficient during spraying, the coating is uneven, resulting in obvious thickness difference of the glue layer. The gluing precision is also difficult to control, and local glue accumulation and lack of glue coexist. More importantly, the prior art ignores the influence of the adhesive on the folding angle, the folding line is not accurate, the deformation rate is high, and finally the finished product often has appearance defects. In addition, the adhesive has poor wetting property, and the paperboard surface often has dry spots, wire drawing or coating rupture, affecting the batch quality stability. SUMMARY

[0005] In view of the shortcomings of the prior art, the present application provides a carton forming method, which solves the problems of insufficient bonding strength, uneven gluing, poor folding precision and poor wetting property of the paperboard surface in the prior art.

[0006] To achieve the above purpose, the present application is realized by the following technical scheme: a carton forming method, comprising the following steps: S1, paperboard information acquisition and positioning: sending the pre-cut corrugated paperboard into the forming area, collecting the thickness, moisture content and on-site environment temperature and humidity information of the corrugated paperboard, and positioning the paperboard edge and indentation data based on image recognition; S2, parameter-driven folding operation: controlling the multi-point linkage servo folding mechanism to perform folding based on the paperboard edge and indentation data, the folding angle is 80°-100°, the folding pressure is 30-60N, and the folding speed is 100-300mm / s, and periodic feedback correction is performed during folding; S3, Environment-related adhesive bonding: based on the folded paperboard, the adhesive is sprayed by the nozzle according to the thickness, moisture content and environmental humidity of the paperboard, the temperature of the nozzle is 165-185℃, the spraying amount per unit length is 0.5-2.5g / s, and the spraying path is calibrated by image recognition; S4, closed-loop control of compression shaping: after the bonding is completed, a compression pressure of 50-80N / cm2 is applied to the paperboard joint, the compression time is 2-5 seconds, and the joint state is judged and the compression control is controlled according to the monitoring result; S5, switching based on identified box type: after the compression shaping is completed, the RFID tag information attached to the paperboard is identified, the box type parameters are called and the process control module is set according to the switching.

[0007] Preferably, in step S1, the positioning of the paperboard edge and the crease data based on image recognition comprises: The paperboard surface image is obtained by using a high-precision image sensor, and the edge of the paperboard is detected and the crease position is identified by image recognition; The image data obtained is processed, and the image processing includes image denoising, edge enhancement and morphological operation; the image recognition data is combined with the physical characteristics of the paperboard to further determine the crease position and calculate the corresponding positioning error.

[0008] Preferably, in step S2, the periodic feedback correction during the folding process comprises: In each folding cycle, the folding angle, folding position and pressure change of the paperboard are monitored in real time by the sensor, and the real-time data is fed back to the central control system; The control system compares the real-time monitoring data with the preset target folding parameters, adjusts the folding speed, angle and pressure of the servo system according to the deviation, and ensures the accurate execution of each folding action; If the monitored deviation exceeds the preset limit value, the driving parameters of the folding mechanical arm are adjusted until the deviation is reduced to an acceptable range, so that the geometric shape and strength of the paperboard during the forming process meet the requirements.

[0009] Preferably, the comparison of the real-time monitoring data with the preset target folding parameters comprises: Before each folding, the current geometric shape of the paperboard is compared with the preset target folding parameters by the central control system, and the target folding parameters are generated according to the paperboard type, folding process requirements and historical data; The deviation value of the real-time data and the target folding parameters is input to the control system, and the folding angle, speed and pressure are dynamically adjusted according to the deviation value.

[0010] Preferably, in step S3, the adhesive comprises the following components by weight: Polyvinyl alcohol: 30-50 parts; Redispersible latex powder: 10-20 parts; Calcium stearate: 2-5 parts; Water: 100-150 parts; Isothiazolinones: 0.2-0.5 parts; Hydroxypropyl methylcellulose: 1-3 parts; Nonylphenol polyoxyethylene ether: 0.5-1 part.

[0011] Preferably, the nonylphenol polyoxyethylene ether is a nonionic surfactant with 10 ethoxy units in the molecule, with an HLB value between 13 and 14, and is a colorless liquid at room temperature Preferably, in step S4, the joint state judgment and pressure compensation control according to the monitoring results include: During the pressing process, the pressure sensor is used to monitor the pressing force and deformation of the paperboard joint in real time, and the adhesion quality of the joint is detected; If there is unevenness or uneven adhesion at the joint, the control system sends a pressure compensation signal to automatically adjust the pressing pressure; the system adjusts the pressing time according to the joint state feedback to ensure uniform and complete adhesion of the paperboard joints.

[0012] Preferably, the detection of the adhesion quality of the joint includes: During the pressing process, the pressure sensor is used to monitor the pressure distribution and deformation of the joint in real time, and identify whether there are gaps and uneven pressing marks in the joint; The shape of the joint is analyzed, and the adhesion quality of the joint is evaluated by combining image recognition and pressure data to detect whether there are incomplete adhesion and raised areas; When the deformation of the joint exceeds the preset standard, the system will automatically trigger the pressure compensation operation and adjust the pressing force and extend the pressing time to ensure uniform pressure distribution at the joint.

[0013] Preferably, in step S5, the box type parameters are retrieved and the process control module settings are switched according to the box type parameters, including: By reading the RFID tag attached to the paperboard, the box type parameters required for the paperboard forming are obtained, including the folding angle, glue spraying amount, pressing time and pressure; According to the read box type parameters, the central control system automatically retrieves the corresponding process template and sends adjustment instructions to each control module, including the parameter settings of the folding mechanism, glue spraying system and pressing mechanism; After the process parameters are switched, self-checking is performed to ensure that each module can operate correctly after the switching is completed.

[0014] Preferably, the automatic retrieval of the corresponding process template comprises: After identifying the RFID tag information on the paperboard, the system calls the preset box type parameters according to the data in the tag, the box type parameters including folding angle, glue spraying amount, pressing time and pressing pressure, and uses these parameters in combination with the physical properties of the paperboard; According to the read box type parameters, the central control system automatically retrieves the corresponding process template from the stored template library, which stores the folding, glue spraying and pressing process parameters of different paperboards and box types; After the process template is retrieved, the system automatically sends adjustment instructions to each process module.

[0015] The present application provides a carton forming method. It has the following advantages: 1. The present application uses a compounded adhesive system, introduces polyvinyl alcohol and redispersible latex powder for synergistic effect, and realizes stronger paperboard bonding strength. Compared with the single-component adhesive in the prior art, which is prone to delamination and fracture, the problem of insufficient adhesion is effectively avoided.

[0016] 2. By adding nonylphenol polyoxyethylene ether in the adhesive, the wetting performance is improved, the sizing is more uniform, and there are no obvious spots at the paperboard joint. The irregular spraying problem caused by poor wetting in the traditional process is improved in this scheme, solving the difficulty of local glue accumulation and uneven spraying.

[0017] 3. The specific spraying temperature and glue spraying rate are matched and set, so that the adhesive has good fluidity, ensuring the smoothness and precision control of the folding process. Unlike the prior art, which is prone to folding angle deviation, the controllability is stronger, the folding line is not biased, the edge is clear, and the structural deformation problem is avoided.

[0018] 4. The present application realizes the cooperation between functions through the double matching of process and formula, so that the final carton performs stably in multiple dimensions such as appearance, strength and sizing uniformity. Compared with the traditional technology which pursues single performance but has unbalanced overall performance, this scheme realizes the cooperation between functions, which is not only practical, but also more conducive to large-scale production. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The present application provides a carton forming method. It has the following advantages: DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0021] Reference is made to the accompanying drawings Figure 1 The embodiment of the present application provides a carton forming method, comprising the following steps: S1, paperboard information acquisition and positioning: the pre-cut corrugated paperboard is sent into the forming area, the thickness, moisture content and on-site environmental temperature and humidity information of the corrugated paperboard are acquired, and the paperboard edge and indentation data are positioned based on image recognition; In the carton forming process, first, the pre-cut corrugated paperboard is sent into the forming area. In order to ensure that the subsequent folding and bonding operations can be carried out efficiently and accurately, the physical properties of the corrugated paperboard and the environmental conditions are first monitored and collected in real time. In this process, advanced sensor technology and image recognition technology are used to achieve comprehensive acquisition and accurate positioning of the paperboard information.

[0022] Generally, first, the thickness, moisture content and on-site environmental temperature and humidity information of the paperboard are collected by the sensor. These information has important influence on the subsequent folding, bonding and other processes, especially under different environmental conditions, the physical properties of the paperboard will change, so accurate real-time monitoring is needed before forming. Specifically, the temperature and humidity sensor can accurately collect the environmental temperature and humidity data in the temperature range of 10-50℃, ensuring the stability and reliability of the data.

[0023] As an option, when collecting temperature and humidity data, the system uses an environmental temperature and humidity adjustment system, which can adjust appropriately according to the real-time collected temperature and humidity changes and correct the moisture content of the paperboard. This enables the system to adjust the moisture content of the paperboard in real time according to environmental changes, so as to ensure that the subsequent bonding process will not be affected by external environmental changes.

[0024] In terms of image recognition positioning of the paperboard, specifically, the system captures the surface of the paperboard in real time through a high-precision image sensor and processes the captured images. Image processing includes edge detection and indentation data extraction, using advanced edge detection algorithms (such as Canny edge detection) and image denoising and morphological operations. These processing procedures can effectively extract the edge lines and crease positions of the paperboard from the original images, thereby providing accurate positioning basis for the subsequent folding operation.

[0025] In one possible implementation, the image recognition system will compare the actual collected image data with the preset paperboard model in real time, and continuously correct the recognition results through error analysis to ensure positioning accuracy. The recognition results will be transmitted to the central control system to guide the actions of the folding and bonding mechanism.

[0026] In some embodiments, the image recognition system not only locates the edge lines and creases of the paperboard, but also accurately calibrates the indentation data of the paperboard. The indentation data is combined with the physical characteristics of the paperboard through image processing algorithms to further calculate and correct the positioning error. This correction process involves deviation analysis based on real-time data and preset standards, and dynamically adjusts the positioning parameters of the system according to the error size.

[0027] During this process, the system also periodically verifies the image recognition results to ensure that the positioning accuracy of the paperboard edge and indentation position remains within a relatively stable range, thereby providing reliable control basis for subsequent folding operations.

[0028] Assuming that the indentation position of the paperboard is (x i , y i ) in the image, the positioning error δ can be calculated by the following formula: In the formula, (x target , y target ) is the preset indentation position coordinate of the paperboard, and (x i , y i ) is the actual recognized indentation position. The error δ is used to adjust the positioning accuracy of the paperboard to ensure the accuracy of each folding action.

[0029] Generally, the positioning accuracy error δ is set within an acceptable range, such as within 0.5 mm, to ensure that subsequent operations are not affected by excessive deviation.

[0030] In one possible implementation, if the positioning error exceeds the set threshold during folding, the system will automatically adjust the parameter settings of image recognition through a feedback correction mechanism to further improve the positioning accuracy and ensure that the geometry during folding meets the requirements.

[0031] S2, parameter-driven folding operation: based on the edge and indentation data of the paperboard, a multi-point linkage servo folding mechanism is controlled to perform folding, the folding angle is 80°-100°, the folding pressure is 30-60N, the folding speed is 100-300mm / s, and periodic feedback correction is performed during folding. To improve the folding accuracy and production efficiency during the carton forming process, a parameter-driven folding operation method is adopted. Through the analysis of the paperboard edge and crease data collected in the previous steps, the system can accurately control the multi-point linkage servo folding mechanism to perform the folding operation. The folding angle range is set to 80° to 100°, the folding pressure is 30 to 60 N, and the folding speed is between 100 to 300 mm / s. The specific folding parameters will be adjusted based on the real-time collected paperboard characteristics and environmental data, ensuring the accuracy and consistency of each folding action.

[0032] Generally, the edge and crease data of the paperboard are obtained through an image recognition system. By accurately identifying the edge position and crease point of the paperboard, the system can calculate the folding parameters in real time and accurately control the motion of the servo folding mechanism based on these data. The folding angle is usually set to 80° to 100°, and the folding pressure is set to 30 N to 60 N, which can ensure that the paperboard maintains good strength and form during folding.

[0033] As an option, the folding speed during the folding process is set to 100 to 300 mm / s. This speed range can balance the folding accuracy and production efficiency, while avoiding paperboard deformation or excessive compression caused by excessively high or low folding speed. In the case of high-speed folding, the paperboard may be broken or poorly bonded due to a lack of sufficient time to adapt to the folding pressure, so speed control is needed to optimize the overall production process.

[0034] Specifically, during the folding operation, the servo system will periodically feedback and correct based on the actual situation of the paperboard. By monitoring the folding angle, folding position, and applied pressure of the paperboard in real time, the control system can compare the real-time data with the target folding parameters. If the deviation in the folding process is detected to exceed the preset threshold, the system will automatically adjust the driving parameters of the servo folding mechanism to ensure the accuracy of each folding.

[0035] In a possible implementation, the periodic adjustment of the feedback correction mechanism can be realized through a PID control algorithm. The main purpose of this algorithm is to minimize the errors of folding angle, pressure, and speed. The specific algorithm can be described by the following formula: e(t) = θ target - θ actual ; In the formula, e(t) is the error of the folding angle, θ target is the target folding angle, and θ actual is the real-time measured folding angle. By calculating the current error, the PID controller will adjust the folding speed, angle, and pressure until the error is reduced to the set tolerance range.

[0036] In some embodiments, the control strategy of the servo system not only limited to PID control, but also combined with fuzzy control algorithm, to adapt to different paperboard types and folding conditions. The fuzzy controller adjusts the folding parameters intelligently by inputting the thickness, moisture content and other information of the paperboard, to further improve the folding accuracy and adaptability.

[0037] In the control of folding pressure, the following formula is used: F = k * Δx; In the formula, F is the applied folding pressure, k is the elastic constant of the paperboard, and Δx is the deformation of the paperboard during folding. This formula is used to describe the relationship between pressure and paperboard deformation, to ensure that the folding process does not cause excessive compression or damage to the paperboard.

[0038] Generally, if the folding angle or pressure deviation of the paperboard is found to be too large during folding, the system will issue an alarm signal and take appropriate compensation measures. For example, when the folding angle deviation is greater than 2° or the folding pressure deviation is greater than 5N, the system will automatically adjust the servo drive parameters to ensure that the folding operation can re-enter the standard control state.

[0039] As another option, the control system can also integrate a real-time data analysis module, which gradually optimizes the control parameters through the accumulation and analysis of historical data, thereby improving the stability and consistency of the folding process. This optimization process can be performed after each production run through the system self-checking function, and the system parameters can be updated according to the self-checking results to adapt to different paperboard materials and production environments.

[0040] S3, environment-related adhesive bonding: based on the paperboard after folding by the folding mechanism, the system controls the nozzle to spray adhesive according to the thickness, moisture content and environmental humidity of the paperboard, the nozzle temperature is 165-185℃, the spraying amount per unit length is 0.5-2.5g / s, and the spraying path is calibrated by image recognition; In this embodiment, during the carton forming process, the spraying operation of the adhesive is closely related to the physical properties of the paperboard and the environmental conditions. Specifically, based on the paperboard after folding by the folding mechanism, the system controls the working parameters of the nozzle according to the thickness, moisture content and environmental humidity of the paperboard, to ensure that the sprayed adhesive can form a uniform bonding layer on the surface of the paperboard, thereby ensuring the bonding quality. In this process, the nozzle temperature is set to a range of 165℃ to 185℃, and the spraying amount per unit length is 0.5g / s to 2.5g / s, to ensure that the amount and quality of the adhesive spraying meet the actual needs. In order to further improve the bonding effect, the spraying path is calibrated in real time by the image recognition system, to ensure that the adhesive can be accurately sprayed to the specified area of the paperboard.

[0041] Generally, the spraying amount of the adhesive and the temperature of the nozzle are adjusted by real-time collected data of the thickness, moisture content and environmental humidity of the paperboard. Since the moisture content of the paperboard and the environmental humidity directly affect the fluidity and adhesion of the adhesive, the system dynamically adjusts the working conditions of the nozzle according to these data. For example, in a high-humidity environment, the moisture content of the paperboard may be high, at which time the sprayed adhesive needs to be adjusted to a lower spraying amount and a higher temperature to ensure that the adhesive can better penetrate the surface of the paperboard and form a firm bond.

[0042] As an option, the humidity sensor in the system can not only collect real-time environmental humidity information, but also monitor the change of the moisture content on the surface of the paperboard. If it is found that the moisture content deviates from the preset range during spraying, the system will automatically adjust the working conditions of the nozzle, such as the spraying amount and the temperature, to compensate for the change of the moisture of the paperboard. For example, when the moisture content of the paperboard is low, the temperature of the nozzle may be increased to close to 185℃ to ensure that the adhesive can be uniformly distributed on the surface of the paperboard and enhance its adhesion.

[0043] Specifically, after the folding operation is completed, the indentation position and edge information on the surface of the paperboard have been positioned by the image recognition system and provide accurate data for the subsequent spraying path of the adhesive. The image recognition system will calibrate the spraying path of the nozzle according to the shape and folding position of the paperboard, so as to ensure that the adhesive can be accurately sprayed at the joint part and avoid waste or uneven coverage of the adhesive.

[0044] In a possible implementation, the system will adjust the temperature of the nozzle in real time to keep it within an optimal range. Through multiple data analysis of temperature, humidity and moisture content of the paperboard, the system can automatically optimize the working state of the nozzle. For example, the system dynamically adjusts the temperature and spraying amount of the nozzle through the PID control algorithm to ensure the stability and uniformity of the adhesive spraying. In actual production, the adjustment formula of the temperature and the spraying amount is as follows: Q=k·(T target -T current )+k′·(H env -H target ); In the formula, Q is the required spraying amount, T target and T current are the target temperature and the current temperature respectively, H env and H target are the environmental humidity and the target humidity respectively, and k and k' are adjustment coefficients, reflecting the influence of temperature and humidity on the spraying amount.

[0045] In some embodiments, the adjustment of the spray head temperature and spray volume can also be associated with the climate changes of the external environment. For example, in an environment with high temperature and low humidity, the system can reduce the spray volume while increasing the spray head temperature to ensure the effective adhesion of the adhesive. In an environment with higher humidity, the spray volume can be increased to ensure that the adhesive can fully cover and form a strong bond with the surface of the paperboard.

[0046] In addition, in order to further improve the spraying precision, the system integrates image recognition technology to calibrate the spraying path. Before each spraying, the image recognition system will accurately scan the actual position and shape of the paperboard, and calibrate the spraying path of the spray head to avoid spraying deviation caused by changes in the shape of the paperboard.

[0047] Specifically, the image recognition system detects the precise position of the paperboard edge and the indentation, and through image processing, it calculates the adjustment amount of the spraying path in real time to ensure that the adhesive is accurately sprayed at the joint of the paperboard. This calibration process is based on computer vision algorithms and uses edge detection and image matching techniques to ensure the accuracy of the spraying path.

[0048] S4, closed-loop control of pressing and shaping: after the adhesion is completed, a pressing pressure of 50-80 N / cm is applied to the joint of the paperboard for 2-5 seconds, and the joint state is judged and the pressing control is adjusted according to the monitoring results; 2 In this embodiment, after the adhesion step of the paperboard is completed, a pressing pressure is applied to the joint of the paperboard to ensure the adhesion quality of each joint of the paperboard. Through the closed-loop control system, the pressing pressure applied to the joint is accurately controlled within the range of 50-80 N / cm 2 , and the pressing time is controlled for 2 to 5 seconds. This process is feedback corrected by the real-time monitoring system according to the joint state, and when the joint state is not ideal, the system automatically adjusts the pressure to ensure that the adhesion quality and the final shape of the paperboard meet the predetermined requirements.

[0049] Generally, after the adhesion operation is completed, the joint of the paperboard needs to be pressed to enhance the bonding strength and ensure the stability of the paperboard shape. The control system dynamically adjusts the pressing pressure and pressing time applied according to the real-time monitoring of the joint state (such as pressure, deformation, adhesion quality, etc.). This can ensure that the joint of the paperboard receives uniform and continuous pressure, so that the paperboard does not loosen or bond insecurely during the forming process.

[0050] ​As an alternative, during the joint state monitoring process, the system employs multiple sensors for data collection, including pressure sensors, deformation sensors, etc. These sensors can monitor the pressure and deformation of the joint in real time, thus making accurate assessments of the bonding state of the paperboard. When insufficient pressure or uneven bonding is detected at the joint, the system will issue a compensation signal by adjusting the pressing pressure or extending the pressing time.

[0051] Specifically, the closed-loop control system compares the real-time collected pressure data with the preset target pressure. When the deviation between the pressure data and the target value exceeds the set threshold, the control system will automatically adjust according to the preset algorithm. This adjustment is executed through the servo drive system to ensure that the pressure at the paperboard joint meets the set requirements. The control of pressing time is also based on real-time feedback mechanism to ensure the stability and uniformity of each pressing operation.

[0052] In one possible implementation, the closed-loop control system calculates and adjusts the pressure and time through the following formula: P = P target + ΔP(t); In the formula, P is the actual pressing pressure, P target is the target pressing pressure, and ΔP(t) is the pressure deviation, which is adjusted according to real-time monitoring data over time. The system dynamically adjusts the pressing force through real-time data to keep it stable within the range of 50-80 N / cm 2 .

[0053] In some embodiments, the time control during the pressing process is also a key parameter. In actual production, when the pressing time is too short, the paperboard joint may not be firmly bonded; while if the time is too long, it may cause paperboard deformation or excessive curing of the adhesive. Therefore, the system determines whether to extend or shorten the pressing time by monitoring the pressure and deformation. For example, when the deformation of the joint is monitored to exceed the predetermined range, the system will automatically extend the pressing time to ensure that the joint is fully and stably bonded.

[0054] In addition, in order to optimize the entire pressing process, the system also introduces an adaptive algorithm to learn and adjust according to the specific data of each production. After completing a round of pressing, the system automatically analyzes the relationship between pressure, time and deformation, and optimizes the pressing strategy for the next time according to the analysis results. This feedback mechanism makes the entire production process more intelligent and adaptive, thus improving production efficiency and product quality.

[0055] Specifically, the system stores and analyzes data after each operation and updates control parameters based on historical data. For example, by collecting a large amount of pressing data, the system can automatically adjust the setting range of pressing pressure and time to adapt to different paperboard types, environmental conditions, and adhesive characteristics.

[0056] S5, Box Type Switching Based on Recognition: After completing the pressing and shaping, the RFID tag information attached to the paperboard is recognized, the box type parameters are retrieved, and the process control module settings are switched accordingly; In this embodiment, after completing the pressing and shaping operation of the paperboard, the system automatically retrieves the corresponding box type parameters by recognizing the RFID tag information attached to the paperboard, and adjusts the settings of the process control module according to these parameters. Through this process, the system can intelligently identify the specifications and types of paperboard, and automatically adjust subsequent folding, spraying, and pressing operations according to different box type requirements, to improve production efficiency and precision.

[0057] Generally, the RFID tag stores detailed box type parameters required by the paperboard, including but not limited to folding angle, glue spraying amount, pressing time and pressure, etc. By reading the information in the RFID tag, the system can accurately obtain the required box type data, and then adjust the settings of the process control module to ensure that each paperboard can be processed individually according to its specifications.

[0058] As an option, the RFID tag not only stores box type parameters, but also may include physical characteristic data of the paperboard (such as thickness, hardness, texture, etc.), which will further help the system to optimize the production process according to the characteristics of different paperboards. For example, for thicker paperboard, the system may need to increase the pressing time or adjust the folding angle to ensure that the final carton quality meets the standard requirements.

[0059] Specifically, after the paperboard is pressed and shaped and the adhesion is completed, the system recognizes the RFID tag on the paperboard in real time through the RFID reader and analyzes the box type parameters stored therein. These parameters are transmitted to the central control system, which automatically adjusts the settings of the process control module according to the transmitted data. For example, if the parameters contained in the tag indicate that the paperboard is a "standard box", the system will automatically select the corresponding process template, such as a folding angle of 90°, a glue spraying amount of 1.5g / s, etc.; if the parameters contained in the tag indicate that the paperboard is a "reinforced box", the system will adjust the folding angle, pressure, etc. to ensure the strength of the carton.

[0060] In one possible implementation, the retrieval of the box type parameters and the switching of the process settings are achieved through a software algorithm. Specifically, the system queries a pre-set box type parameter database and transmits the relevant parameters to each process control module, updating the settings of the folding, glue spraying, and pressing modules in real time. For example, assuming that the box type parameters provided in the RFID tag are as follows: Folding angle = 95°, glue spraying amount = 2.0 g / s, pressing pressure = 60 N / cm 2 , pressing time = 4 seconds.

[0061] These parameters will be automatically transmitted to the folding machine, glue spraying machine, and pressing machine, thereby adjusting the corresponding working states and ensuring the smooth progress of the production process.

[0062] In some embodiments, to ensure the accuracy of the parameter switching, the system will perform a self-check after each box type switching to verify whether the settings of each process module are correct. The self-check process includes checking the folding angle, glue spraying amount, pressing pressure, and time, and making fine adjustments as needed to ensure the accuracy of the process execution.

[0063] In addition, the data storage of the RFID tag adopts a highly standardized format, ensuring the compatibility of different paperboard types. The tag uses passive RFID technology, which can be activated by the signal emitted by the reader without external power supply, thereby achieving efficient data reading. In actual application, the storage capacity and data transmission rate of the RFID tag can meet the needs of large-scale production environment, ensuring fast and stable data transmission.

[0064] Specifically, the storage format of the RFID tag usually includes field identifier (ID), box type parameters (such as folding angle, glue spraying amount, etc.), production date, paperboard type, and other information, all of which are stored in a standard format for quick decoding and querying. When reading the paperboard information, the tag reader compares with the database to confirm the required process settings.

[0065] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0066] Please refer to the attached Figure 1 : Example 1: Component ratio (consisting of components in percentage by weight): polyvinyl alcohol: 40 parts, redispersible latex powder: 15 parts, calcium stearate: 3 parts, water: 120 parts, isothiazolinone: 0.35 parts, hydroxypropyl methylcellulose: 2 parts, nonylphenol polyoxyethylene ether (containing 10 ethoxy units, HLB value about 13.5): 0.7 parts.

[0067] Preparation steps: All components were added into a high-speed shearing dispersion device and stirred at room temperature (25℃±2℃) for 45 minutes to form a uniform emulsion.

[0068] The paperboard thickness was 4.0mm, the moisture content was 9.5%, the ambient temperature was 24℃, and the relative humidity was 55%; The folding angle was controlled at 90°, the folding pressure was 45N, and the folding speed was 200mm / s; The adhesive nozzle was heated to 175℃, and the spraying amount per unit length was controlled at 1.5g / s; the spraying path was corrected in real time by an image recognition system; The pressure applied to the paperboard joint in the pressing stage was 65N / cm2, and the pressing time was 3 seconds; After RFID identification, the target box type parameters (such as folding angle 88°, pressing 4 seconds, and adhesive spraying 1.6g / s) were retrieved to automatically complete the process module adjustment.

[0069] Example 2: The component ratio (component composition by weight percentage): polyvinyl alcohol: 30 parts, redispersible latex powder: 10 parts, calcium stearate: 2 parts, water: 100 parts, isothiazolinone: 0.2 parts, hydroxypropyl methyl cellulose: 1 part, and nonylphenol polyoxyethylene ether: 0.5 part.

[0070] Preparation steps: The components were mixed at 20℃, pre-stirred at low speed for 10 minutes, and then stirred at a shearing rate of 800rpm for 30 minutes to obtain a milky adhesive.

[0071] The paperboard thickness was 3.0mm, the moisture content was 6.0%, the ambient temperature was 20℃, and the relative humidity was 40%; The folding angle was controlled at 80°, the folding pressure was 30N, and the folding speed was 100mm / s; The adhesive nozzle was heated to 165℃, and the spraying amount was controlled at 0.5g / s; The pressing pressure was controlled at 50N / cm2, and the pressing time was 2 seconds; After RFID identification of the box type, the set parameter template (such as folding angle 81°, adhesive spraying 0.6g / s, and pressing 2.5 seconds) was switched to complete the box type switching.

[0072] Example 3: The component ratio (component composition by weight percentage): polyvinyl alcohol: 50 parts, redispersible latex powder: 20 parts, calcium stearate: 5 parts, water: 150 parts, isothiazolinone: 0.5 parts, hydroxypropyl methyl cellulose: 3 parts, and nonylphenol polyoxyethylene ether: 1 part.

[0073] Preparation steps: In a closed stirred tank at 30°C, the stirring speed is 1200 rpm, and the continuous shearing stirring is maintained for 60 minutes to ensure that the system is uniform and has no stratification.

[0074] The thickness of the paperboard is 5.5 mm, the moisture content is 14.0%, the ambient temperature is 30°C, and the relative humidity is 80%; The folding angle is 100°, the folding pressure is 60 N, and the folding speed is 300 mm / s; The adhesive nozzle is heated to 185°C, and the unit length of the spray is controlled at 2.5 g / s; The pressing pressure is 80 N / cm2, and the pressing time is 5 seconds; After reading the RFID, switch to the box template (folding angle 99°, glue spraying 2.4 g / s, pressing 4.8 seconds), complete the automatic adjustment and execute the next forming cycle.

[0075] Comparative Example 1: Compared with Example 1, the difference is that nonylphenol polyoxyethylene ether is omitted in the adhesive component, and the rest of the component ratio and parameters such as sizing, folding, and pressing are the same.

[0076] Comparative Example 2: Compared with Example 1, the difference is that no redispersible latex powder is added to the adhesive, and the rest is the same.

[0077] Comparative Example 3: Compared with Example 1, the difference is that the addition amount of polyvinyl alcohol is 25 parts, which is lower than the set lower limit of 30 parts, and the rest is the same.

[0078] Comparative Example 4: Compared with Example 1, the difference is that the amount of isothiazolinone is reduced from 0.35 parts to 0.1 parts, and the amount of nonylphenol polyoxyethylene ether is reduced from 0.7 parts to 0.5 parts, and the rest of the components are the same as Example 1.

[0079] Experiment 1: Purpose of the experiment: compare the differences in adhesive strength of the cartons prepared in Example 1 and Comparative Examples 1, 2, 3, and 4, and evaluate the effects of different components and steps on the adhesive effect.

[0080] Experimental steps: Sample preparation: Cartons are prepared according to Example 1 and Comparative Examples 1, 2, 3, and 4. At least 3 carton samples are prepared for each group to ensure that the size and structure of each group of samples are consistent.

[0081] Tensile test: The seam part of the carton is fixed in the clamps of the tensile testing machine to ensure uniform stress on the seam.

[0082] Start the tensile testing machine and slowly apply the tensile force until the seam part is completely broken.

[0083] Record the maximum tensile force (unit: N) displayed by the testing machine.

[0084] Data recording: Record the breaking tensile force of each sample, taking at least 3 independent measurements and averaging them.

[0085] Result analysis: According to the maximum tensile force value of each group of cartons, calculate the difference in adhesion strength between different examples and comparative examples.

[0086] Compare the maximum tensile force of each group and analyze its effect on adhesion (see Table 1 for experimental results).

[0087] Table 1 From Table 1, we can see that: The results of Experiment 1 show that the adhesive formulation in Example 1 has significantly higher adhesion strength, which is closely related to the synergistic effect of each component in the adhesive. The key components used in Example 1, such as polyvinyl alcohol, redispersible latex powder, and nonylphenol polyoxyethylene ether, interact with each other during the bonding process, enhancing the bonding performance of the paperboard joints. As the base component of the adhesive, polyvinyl alcohol has good solubility and adhesion, which can effectively form strong physical adhesion with the paperboard surface. The addition of redispersible latex powder further improves the adhesion and water resistance of the adhesive, ensuring the strength performance of the carton in a humid environment.

[0088] In addition, nonylphenol polyoxyethylene ether as a surfactant plays a crucial role in the sizing process. It not only improves the flowability of the adhesive, allowing it to be evenly coated on the paperboard surface, but also increases the contact area and adhesion between the adhesive and the paperboard by improving the wettability of the paperboard surface. In the comparative experiment, the sample without this component showed lower adhesion strength, indicating that nonylphenol polyoxyethylene ether is indispensable in improving the adhesion effect.

[0089] Compared with the comparative example group, the better performance of Example 1 is also due to the innovative process control, such as precise control of the glue spraying amount and sizing temperature. In Example 1, the adhesive nozzle temperature is maintained at 175°C, which not only helps the flowability of the adhesive, but also ensures the adhesion and durability of the adhesive during the glue spraying process. In the experiment, by precisely controlling the spraying amount, it avoids too much or too little adhesive coating, ensuring uniform adhesion of the paperboard joints, while this point is poor in the comparative examples that remove some innovative components or process adjustments. Therefore, the process innovation in Example 1 and the reasonable collocation of the formula together improve the adhesion strength of the carton, providing strong protection for the service life and stability of the carton in actual application.

[0090] Experiment 2: Experimental Purpose: By comparing the folding accuracy and appearance differences between Example 1 and Comparative Examples 1, 2, 3, 4 samples, evaluate the impact of different components on the appearance and folding quality of cartons.

[0091] Experimental Steps: Sample Preparation: Prepare carton samples according to Example 1 and Comparative Examples 1, 2, 3, 4, ensuring that the size, paperboard type, and folding method are consistent for each group of samples.

[0092] Folding Angle Measurement: Use an angle measuring instrument to measure the folding angle of each sample, record the deviation between the actual folding angle and the preset target angle.

[0093] Take three independent measurements for each sample and take the average.

[0094] Appearance Quality Detection: Visually inspect the folding parts of the carton to ensure there are no creases, cracks, or other appearance defects.

[0095] Use a standard test bench to unfold the carton and check if the seams are complete, without obvious deformation or irregular folding marks.

[0096] Data Recording and Analysis: Record the folding angle deviation and appearance defect conditions of each sample.

[0097] Compare the folding accuracy and appearance quality differences between different example and comparative example samples (see Table 2 for experimental results).

[0098] Table 2 From Table 2: Example 1 performs better than other comparative examples in terms of folding accuracy and appearance quality, indicating that the innovative formula and control mechanism of the invention in the carton folding process helps to improve the structural integrity of the carton. The special formula of the adhesive and the optimized process control in Example 1 make the paperboard maintain higher stability when folding. Especially the good combination of polyvinyl alcohol and redispersible latex powder, these components provide the paperboard with stronger folding resistance, so that the paperboard can better maintain the preset folding angle when folding, without excessive deviation or deformation.

[0099] From a mechanistic perspective, the use of nonylphenol polyoxyethylene ether as a surfactant in Example 1 significantly improved the wettability of the paperboard surface. The increased wettability increased the contact area of the adhesive with the paperboard surface, resulting in a more uniform joint and a reduced likelihood of irregular creases or cracks during folding. This is clearly evident from the experimental data, which shows a higher appearance quality score for Example 1, indicating that the uniform application of adhesive and the good adhesion to the paperboard surface during folding worked together to ensure that the folded carton had no significant defects.

[0100] In addition, the precise control of the folding angle and the sizing amount in Example 1 ensured that each fold achieved the desired result. During folding, the adhesive performed optimally at a reasonable temperature and pressure, avoiding the folding inaccuracies that can occur due to excessively high or low temperatures. Compared to the comparative examples, the samples that did not use this fine process control exhibited significant folding deviations and appearance defects, further demonstrating the importance of process and formulation innovation in ensuring the structural and appearance quality of cartons.

[0101] Experiment 3: Purpose of the experiment: Compare the flowability and sizing uniformity of the adhesives used in Example 1 and Comparative Examples 1, 2, 3, and 4, and evaluate the effects of different components on the performance of the adhesive.

[0102] Experimental steps: Adhesive flowability test: Use a viscometer to test the flowability of each group of adhesives. Ensure that the adhesive reaches a stable state at 175°C (or the corresponding test temperature) during testing.

[0103] Record the viscosity value of each sample and evaluate the flowability based on the results.

[0104] Sizing uniformity test: Set the adhesive spray head to the same spraying temperature (e.g., 175°C) and adjust the spraying speed to a specified value (e.g., 1.5 g / s).

[0105] Perform sizing operations on the same paperboard sample, ensuring that the spraying path and coating area are consistent.

[0106] Visually assess the coating uniformity after sizing, checking for the presence of dripping, excessive coating, or insufficient coating. Measure the thickness of the coated area using a measuring tool to evaluate the uniformity of the coating.

[0107] Data recording and analysis: Record the flowability values and sizing uniformity scores for each group of samples. Flowability data is obtained using a viscometer, and sizing uniformity is recorded through manual evaluation and coating thickness measurement.

[0108] By comparing the flowability and sizing uniformity data of different examples and comparative examples, the influence of each group of formulations on the adhesive performance was analyzed (the experimental results are shown in Table 3).

[0109] Table 3 From Table 3, we can see that: The adhesive in Example 1 performs excellently in flowability and sizing uniformity, which is closely related to its unique formulation and component optimization. In particular, the combination of polyvinyl alcohol and redispersible latex powder enables the adhesive to have good flowability at higher temperatures. This flowability ensures that the adhesive can uniformly cover the surface of the paperboard during the sizing process, avoiding the phenomenon of excessive or insufficient coating. Redispersible latex powder not only improves the flowability, but also maintains the adhesion of the adhesive, ensuring long-lasting adhesion on the paperboard contact surface.

[0110] In addition, the addition of nonylphenol polyoxyethylene ether as a surfactant enables the adhesive to better wet the surface of the paperboard during the sizing process. It reduces the surface tension of the paperboard, enabling the adhesive to be more uniformly distributed, avoiding the uneven phenomenon caused by high surface tension during the coating process. Visual inspection results show that the sizing uniformity score of Example 1 is higher, proving the important role of this component in improving coating quality. By adjusting the content of the surfactant, a relatively uniform coating thickness is obtained in the experiment, further ensuring the production quality of the paper box.

[0111] In addition, Example 1 has achieved good results in the optimization of adhesive formulation and spraying process. The adhesive with good flowability exhibits low viscosity during the sizing process, which ensures the stability of the spraying process. Reasonable control of temperature and spraying speed effectively avoids the negative effects that may be caused by high viscosity or uneven coating. These factors work together to ensure that the adhesive of Example 1 can form a uniform and strong coating on the surface of the paperboard, thereby providing reliable guarantees for subsequent bonding and paper box forming.

Claims

1. A carton forming method, characterized in that: The following steps are involved: S1. Cardboard information collection and positioning: Pre-cut corrugated cardboard is fed into the forming area, and the thickness, moisture content, and temperature and humidity information of the corrugated cardboard are collected. The cardboard edge and indentation data are then positioned based on image recognition. S2. Parameter-driven folding operation: Based on the cardboard edge and indentation data, a multi-point linkage servo folding mechanism is controlled to perform folding, with the folding angle being 80°-100°, the folding pressure being 30-60N, and the folding speed being 100-300mm / s. Periodic feedback correction is also performed during the folding process. S3, environmentally-dependent adhesive bonding: The folded cardboard is folded based on the folding mechanism, and the adhesive is sprayed by the nozzle according to the thickness, moisture content and ambient humidity of the cardboard. The nozzle temperature is 165-185°C, the spray rate per unit length is 0.5-2.5g / s, and the spray path is calibrated by image recognition; S4, closed-loop controlled pressing and shaping: After bonding, a pressing pressure of 50-80N / cm2 is applied to the cardboard seams for 2-5 seconds, and the seam status is judged and the pressure is controlled based on the monitoring results; S5. Box type switching based on identification: After completing the pressing and shaping, the RFID tag information attached to the cardboard is identified, the box type parameters are retrieved and the process control module settings are switched accordingly.

2. A carton forming method according to claim 1, characterized in that: In step S1, the positioning of the cardboard edge and indentation data based on image recognition includes: Use high-precision image sensors to acquire images of the cardboard surface, perform edge detection on the images, and identify the edge lines and crease positions of the cardboard; Performing image processing on the acquired image data, wherein the image processing includes image denoising, edge enhancement and morphological operations; The image recognition data is combined with the physical properties of the cardboard to further determine the indentation location and calculate the corresponding positioning error.

3. A carton forming method according to claim 1, characterized in that: In step S2, performing periodic feedback correction during the folding process includes: During each folding cycle, sensors monitor the folding angle, folding position, and pressure changes of the cardboard in real time, and feed the real-time data back to the central control system; The control system compares the real-time monitoring data with the preset target folding parameters and adjusts the folding speed, angle and pressure of the servo system according to the deviation to ensure the precise execution of each folding action; If the detected deviation exceeds the preset limit, the drive parameters of the folding robot arm are adjusted until the deviation is reduced to an acceptable range, ensuring that the geometric shape and strength of the cardboard meet the requirements during the forming process.

4. A carton forming method according to claim 3, characterized in that: The comparing of the real-time monitoring data with the preset target folding parameters includes: Before each fold, the central control system compares the current geometric shape of the cardboard with the preset target folding parameters. The target folding parameters are generated based on the cardboard type, folding process requirements and historical data. The deviation between the real-time data and the target folding parameters is input into the control system, and the folding angle, speed and pressure are dynamically adjusted according to the deviation.

5. A carton forming method according to claim 1, characterized in that: In step S3, the adhesive includes the following components in parts by weight: Polyvinyl alcohol: 30-50 parts; Redispersible latex powder: 10-20 parts; Calcium stearate: 2-5 parts; Water: 100-150 parts; Isothiazolinones: 0.2-0.5 parts; Hydroxypropyl methylcellulose: 1-3 parts; Nonylphenol polyoxyethylene ether: 0.5-1 part.

6. A carton forming method according to claim 5, characterized in that: The nonylphenol polyoxyethylene ether is a nonionic surfactant containing 10 ethoxy units in its molecule, has an HLB value between 13 and 14, and is a colorless liquid at room temperature.

7. A carton forming method according to claim 1, characterized in that: In step S4, the seam status determination and pressure compensation control according to the monitoring results include: During the lamination process, the pressure sensor monitors the lamination force and deformation of the cardboard seams in real time to detect the bonding quality of the seams. If there is unevenness or uneven bonding at the joint, the control system will send a pressure compensation signal to automatically adjust the pressing pressure; The system adjusts the pressing time based on the feedback of the seam status to ensure that the bonding of each seam of the cardboard is uniform and complete.

8. A carton forming method according to claim 7, characterized in that: The testing of the bonding quality at the joint includes: During the lamination process, pressure sensors are used to monitor the pressure distribution and deformation of the joints in real time to identify whether there are gaps or uneven lamination marks in the joints. Perform shape analysis on joints, using a combination of image recognition and pressure data to assess the bonding quality of joints and detect areas of incomplete bonding and warping. When it is detected that the deformation at the seam exceeds the preset standard, the system will automatically trigger the pressure replenishment operation, adjust the pressing force and extend the pressing time to ensure uniform pressure distribution at the seam.

9. A carton forming method according to claim 1, characterized in that: In step S5, the process of retrieving the box type parameters and switching the process control module settings accordingly includes: By reading the RFID tag attached to the cardboard, the box parameters required for the cardboard to be formed are obtained, including the folding angle, glue spraying amount, pressing time and pressure; According to the box type parameters read, the central control system automatically calls the corresponding process template and sends adjustment instructions to each control module. The adjustment instructions include parameter settings for the folding mechanism, glue spraying system and pressing mechanism; After the process parameters are switched, a self-check is performed to ensure that each module can operate in the correct setting state after the switch is completed.

10. A carton forming method according to claim 9, characterized in that: The automatic retrieval of the corresponding process template includes: After identifying the RFID tag information on the cardboard, the system calls the preset box parameters based on the data in the tag. The box parameters include folding angle, glue spraying amount, pressing time and pressing pressure, and combines these parameters with the physical properties of the cardboard. According to the box parameters read, the central control system automatically calls the corresponding process templates from the stored template library. These templates store the folding, gluing and pressing process parameters of different cardboards and box types; After the process template is retrieved, the system will automatically issue adjustment instructions to each process module.

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