Prefabricated vegetable quantitative packaging method and equipment

Abstract

The invention relates to the technical field of food packaging, in particular to a prefabricated vegetable quantitative packaging method and device.The prefabricated vegetable quantitative packaging method comprises the steps that 1, dynamic pre-dehydration is conducted; 2, anti-layering conveying is conducted, specifically, the pre-dehydrated dishes are guided into a vibration conveying groove with the inner wall provided with a flow guide structure, the component dispersion is calculated by analyzing food material vibration energy distribution, and the vibration amplitude is adjusted in real time according to the component dispersion; step 3, delay compensation weighing is carried out; and 4, self-adaptive stripping: unfolding a flexible scraper on the inner wall of the weighing container, detecting the stripping resistance between the scraper and the food material in real time, and adjusting the temperature of the scraper and the linear speed and the screw pitch of a spiral motion track according to the resistance value. Through accurate control of the temperature and the spiral motion, it can be ensured that the stripping process is conducted efficiently, and waste caused by the fact that food materials adhere to the wall of a container is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of food packaging, and in particular to a method and equipment for quantitative packaging of pre-prepared dishes. Background Art

[0002] In the field of industrial packaging of ready-to-heat pre-prepared meals, especially those containing soup stock and mixed with multiple components (such as mapo tofu and braised beef brisket), the existing packaging technology has systematic quantitative deviations due to differences in the physical properties of the ingredients, which are specifically manifested as follows: Weighing distortion caused by solid-liquid separation: Since the fluidity of soup is much higher than that of solid ingredients, it continues to seep during transportation (for example, the oil and sauce in Mapo tofu leak out from the gaps between the tofu), resulting in an artificially high proportion of solids when entering the weighing process. The actual solid-liquid mass ratio after packaging deviates from the process requirements by more than ±10%, resulting in a dry taste or excessive soup after the product is reheated.

[0003] Vibration conveying exacerbates the discretization of components: ingredients with significant density differences (such as spareribs (ρ≈1.8g / cm 3 ) and potato cubes (ρ≈0.8g / cm 3 )) Spatial stratification occurs during vibration conveying due to differences in inertial force. Existing single-point weighing sensors can only capture local mass, causing an imbalance in the actual ratio in the package (tests show that the ratio of spareribs fluctuates by ±15%).

[0004] Therefore, there is an urgent need for a method and equipment for quantitative packaging of pre-prepared dishes to solve the above problems. Summary of the invention

[0005] Based on the above purpose, the present invention provides a method and device for quantitative packaging of pre-prepared dishes, wherein the method for quantitative packaging of pre-prepared dishes comprises the following steps: Step 1: Dynamic pre-dehydration: Place the pre-prepared food with soup on a conveyor belt with adjustable inclination. Use optical sensing to detect the amount of soup loss in real time, and dynamically adjust the inclination and speed of the conveyor belt based on the preset dehydration threshold. Step 2: Anti-stratification conveying: the pre-dehydrated food is introduced into a vibrating conveying trough with a guide structure on the inner wall. The component dispersion is calculated by analyzing the vibration energy distribution of the food, and the vibration amplitude is adjusted in real time accordingly. Step 3: Delayed compensation weighing: import the delivered dishes into the weighing container, record the time T when the weighing value reaches stability, and when T exceeds the reference time corresponding to the dish type, calculate the compensation amount Q based on the T value and add it to the weighing value; Step 4: Adaptive peeling: deploy a flexible scraper on the inner wall of the weighing container, detect the peeling resistance between the scraper and the food in real time, and adjust the scraper temperature and the linear speed and pitch of the spiral motion trajectory according to the resistance value.

[0006] Correspondingly, an embodiment of the present invention further provides a prefabricated dish quantitative packaging device for implementing a prefabricated dish quantitative packaging method according to an embodiment of the present invention, including the following modules: A dynamic pre-dehydration module, including: An optical sensing unit, composed of a light source array and an optical sensor array, where the light source irradiates the liquid seepage area at the end of the conveyor belt at a preset incident angle, and the sensor collects the transmittance distribution data; A processing unit, connected to the optical sensing unit, calculates the mass of the lost soup according to the transmittance distribution gradient, and generates a control instruction based on the dehydration threshold; An execution unit, including an inclination servo motor and a conveyor belt frequency converter, receives the control instruction of the processing unit, and synchronously adjusts the inclination and speed of the conveyor belt; An anti-stratification conveying module, connected to the output end of the dynamic pre-dehydration module through a material channel, including: A vibration analysis unit, composed of an acceleration sensor array installed on the outside of the U-shaped conveying trough, and collects the vibration spectrum of the trough body; A dispersion calculation unit, connected to the vibration analysis unit, extracts the energy variance value in the characteristic frequency interval and outputs the dispersion level; An amplitude regulation unit, including a linear vibration motor and a driver, receives the dispersion level signal, and outputs an amplitude control signal that is inversely linked to the dispersion level; A delay compensation weighing module, connected to the output end of the anti-stratification conveying module through a blanking conduit, including: A weighing sensor unit, which collects the mass data of the weighing container in real time; A stable time detection unit, connected to the weighing sensor unit, identifies the time point when the mass data fluctuates less than the threshold for three consecutive samplings and records the duration T; A compensation calculation unit, with a pre-stored relationship curve database built-in, receives the duration T and the dish type code, and outputs a compensation amount Q when T exceeds the reference time; An adaptive peeling module, integrated on the inner wall of the weighing container, including: A resistance detection unit, composed of a torque sensor and a contact area calculator, and outputs the peeling resistance value in real time; A temperature control unit, including a built-in heating film on the scraper and a temperature sensor, receives the peeling resistance value, and starts heating to the target temperature when the resistance exceeds the critical value; A motion control unit, connected to the resistance detection unit, generates a linear velocity and pitch instruction for a spiral trajectory according to the real-time peeling resistance value, and drives the scraper servo motor.

[0007] Advantages of the present invention: 1. By introducing a dynamic distribution and metering system for liquid materials and adopting multi-point weighing and flow monitoring technologies during the packaging process, the present invention effectively monitors the flow state of the soup, avoiding the problem of falsely high proportion of solid materials caused by soup loss. Through temperature and density monitoring technologies, the fluidity of the soup and solid ingredients is dynamically adjusted to ensure that the solid-liquid ratio meets the process requirements. This method can accurately control the soup loss in real time, distribute and compensate the liquid during transportation, thereby maintaining the stability of the solid-liquid ratio and significantly reducing the error after packaging. During the reheating process of the packaged product, it avoids the problems of dry taste or excessive soup caused by soup loss or excess, improving the reheating reduction and taste consistency of the food.

[0008] 2. The present invention adopts multi-point vibration sensing and hierarchical control technologies. By monitoring the inertial differences and motion states of the ingredients during vibration transportation, it accurately identifies and effectively reduces the ingredient stratification phenomenon caused by density differences. An adaptive adjustment function is added to the conveying device, which can adjust the vibration frequency and amplitude according to the density and shape changes of the ingredients, preventing the stratification phenomenon of high-density and low-density ingredients due to inertial differences. This technology can ensure the uniform distribution of each component throughout the packaging process, thus avoiding the ratio imbalance caused by ingredient stratification. In addition, the present invention combines density analysis technology. By measuring the ingredient density in real time and dynamically adjusting the packaging ratio, it ensures that the ratio error of different components in the package is controlled within ±5%, significantly better than the ±15% fluctuation in the prior art, improving the product consistency and packaging accuracy.

[0009] 3. The present invention introduces an omni-directional multi-point weighing system. By installing multiple weighing sensors, it realizes the precise monitoring of the overall ingredient quality and each component during the packaging process. Different from traditional single-point weighing, this system can sense the overall changes of the ingredients, thus more precisely controlling the proportion of each ingredient and avoiding the overall weighing imbalance caused by local quality errors. Combined with an intelligent compensation algorithm, this system can perform dynamic compensation according to the different physical properties of the ingredients to ensure the accuracy of the weighing value. This compensation method can greatly reduce the weighing error caused by ingredient physical property differences and improve the packaging accuracy. Finally, through these refined control measures, the present invention can control the error range of the entire quantitative packaging system within a very small range, ensuring the consistency and quality stability of the packaged product. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0011] Figure 1It is the flowchart of the steps of the method of the present invention; Figure 2 It is the flowchart of the steps of the method for establishing the functional relationship between the T value and the residual mass in the method of the present invention; Figure 3 It is the structural block diagram of the system of the present invention. Specific embodiments

[0012] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. At the same time, it is noted here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments. For some well-known technologies, those skilled in the art can also adopt other alternative methods for implementation; moreover, the accompanying drawings are only for more specifically describing the embodiments and are not intended to specifically limit the present invention.

[0013] Please refer to Figures 1 - 3 , the embodiment of the present invention provides a method for quantitatively packaging prefabricated dishes. In step 1, the prefabricated dishes with soup enter the packaging system through a conveyor belt. The inclination angle and speed of the conveyor belt are adjustable and it has filter holes to allow some soup to drain. The soup loss is detected in real time through an optical sensor (such as a laser sensor or an infrared sensor). The optical sensor can accurately capture the flow state of the soup and timely feedback the loss of the soup. According to the set pre-dehydration threshold, if the soup loss exceeds the threshold, the system will automatically adjust the inclination angle or speed of the conveyor belt to make more soup drain or slow down the drainage speed, ensuring that the solid-liquid ratio of each batch of products meets the process requirements.

[0014] Through real-time monitoring and dynamic adjustment, the imbalance of the solid-liquid ratio caused by excessive or insufficient soup loss is avoided, ensuring the consistency of the taste and texture of each packaged product.

[0015] Effectively control the dehydration process, avoid excessive soup loss, and thus ensure that the packaged product can maintain an appropriate taste after reheating and avoid a dry taste.

[0016] In step 2, the dishes after dynamic pre-dehydration are conveyed to a vibrating conveyor trough with a guiding structure on the inner wall. The inner wall of this conveyor trough is designed with guiding channels to guide the ingredients to flow along a certain trajectory and avoid stratification between the ingredients.

[0017] By analyzing the vibration energy distribution received by the ingredients in the vibrating conveyor trough, the system can calculate the dispersion degree of each component in real time. This dispersion degree refers to the stratification trend of ingredients with different densities (such as ribs and potato pieces) during vibration.

[0018] According to the change of the dispersion degree, the system automatically adjusts the amplitude of the vibration, making the high-density ingredients and the low-density ingredients evenly distributed, thereby preventing the stratification phenomenon of the ingredients caused by the difference in inertia.

[0019] This technology significantly reduces the stratification of ingredients with large density differences (such as pork ribs and potatoes) during transportation, thus ensuring a more uniform ingredient ratio in each pre-prepared dish and avoiding the problem of too much or too little of a certain ingredient in the package.

[0020] By adjusting the vibration parameters in real time, the movement trajectory of the ingredients can be precisely controlled according to the actual situation, further improving the accuracy and consistency of packaging.

[0021] In step 3, after the transported dish enters the weighing container, the system will record the change in the weighing value in real time and monitor the stabilization time T of the weighing value. This time T refers to the time when the dish reaches a stable state during weighing.

[0022] If it is detected that the stabilization time T exceeds the reference time for the corresponding dish type, the system will calculate the compensation amount Q based on this time T and add this compensation amount Q to the weighing value to ensure the accuracy of the final weighing result.

[0023] The calculation method of the compensation amount Q is based on the deviation between the stabilization time and the standard weighing time, which can accumulate small errors over a long time and finally adjust the weighing value so that the ingredient weight of each package meets the process requirements.

[0024] This method ensures that even during a long weighing process, the weighing deviation that may be caused by the flow of soup or solid ingredients can be compensated, reducing the quality problems caused by inaccurate weighing.

[0025] Through the compensation technology, the quality of the packaged product is more stable, ensuring that consumers can obtain consistent ingredient weight and quality.

[0026] In step 4, a flexible scraper is arranged on the inner wall of the weighing container to strip the residual dishes attached to the inner wall of the container. The scraper is designed with adjustable temperature control and a spiral movement trajectory.

[0027] The system determines whether the dish is successfully stripped by detecting the stripping resistance between the scraper and the ingredients in real time. If the stripping resistance is large, the system will automatically adjust the temperature of the scraper and the linear speed and pitch of the spiral movement trajectory to make it better contact with the ingredients and promote the stripping process.

[0028] The adjustment of temperature and spiral movement ensures that the scraper can smoothly and evenly separate the ingredients from the container wall, reducing the waste of residual ingredients.

[0029] Through the precise control of temperature and spiral movement, it can ensure the efficient progress of the stripping process and avoid the waste caused by ingredients adhering to the container wall.

[0030] This process can adaptively adjust under different types of food ingredients and packaging environments, effectively improving packaging efficiency and reducing manual intervention in the production process.

[0031] In a possible implementation, a light source and an optical sensor array are arranged below the end of the conveyor belt. The light source irradiates the seepage flow (i.e., the lost soup) at a preset incident angle according to the design requirements. The purpose of this design is to let the light irradiate the soup flow at a certain angle so that the change in the light transmittance can accurately reflect the loss of the soup.

[0032] The optical sensor array consists of multiple sensor units and is arranged below the conveyor belt. Each sensor unit detects the intensity of the passing light and calculates the light transmittance. The light transmittance refers to the light penetration ability after the light source irradiates through the soup flow. The more soup there is, the worse the light penetration ability and the lower the light transmittance.

[0033] The light transmittance data of each sensor unit are collected and processed according to the light transmittance distribution gradient. The change in the light transmittance reflects the change in the cross-section of the liquid flow, and thus can be used to calculate the amount of soup lost.

[0034] When calculating, the cross-sectional area of the liquid flow can be obtained through gradient analysis, and combined with the speed of the conveyor belt, the total amount of soup lost can be estimated.

[0035] To calculate the mass of the lost soup more precisely, the system combines a preset soup density-light transmittance mapping table. This mapping table provides density information of different soup types (such as thick soup, clear soup, etc.) at different light transmittances.

[0036] Based on the mapping relationship between the density and light transmittance of the soup, the system can calculate the mass of the lost soup per unit time in real time. This process makes the control of the dehydration amount more precise, not only ensuring the standardization of the food ingredients but also avoiding over-dehydration or under-dehydration.

[0037] Conduct multiple solid-liquid separation cooking experiments on the target pre-made dishes to obtain the soup loss situation under different dehydration conditions through the experiments. Based on these experimental data, the optimal amount of soup loss can be determined.

[0038] During the experiment, sensory evaluation is used as the dominant criterion to determine the maximum allowable soup loss rate corresponding to the best taste. Sensory evaluation considers various factors such as the richness of the taste and the thickness of the soup to ensure the quality of the final product.

[0039] Once the maximum allowable soup loss rate corresponding to the best taste is determined, the system sets the upper limit of the dehydration threshold according to 75%-90% of this value. The set upper limit of the threshold can provide a flexible adjustment space for the production process to avoid over-dehydration of the product.

[0040] The method for setting the upper threshold is designed to control the loss of soup during the dehydration process, keeping it within the range of the best taste, so as not to cause poor taste due to excessive dehydration.

[0041] Through the combination of an optical sensor array and the processing of light transmittance data, the accurate monitoring of the soup loss amount of prefabricated dishes is achieved. Combining with the best taste standard determined by sensory evaluation, a scientific and reasonable dehydration threshold is formulated, significantly improving the quality control during the packaging process of prefabricated dishes, and having very good application prospects.

[0042] In a possible implementation manner, a vibration acceleration sensor array is installed outside the conveying trough. The sensor array is arranged at different positions of the conveying trough for the purpose of monitoring the vibration signal of the trough body. The vibration data captured by the sensor can reflect the distribution characteristics of the prefabricated dish samples during the conveying process.

[0043] The vibration sensor converts the vibration signal of the trough body into spectral data. In the spectrum, different frequency components reflect the motion states of different substances in the trough. Specifically, different states of density-difference components (such as soup, solid ingredients, etc.) will result in different vibration frequencies.

[0044] Through spectral analysis, the system extracts the characteristic frequency intervals related to the density-difference components. These characteristic frequency intervals can reveal the dispersion degree of the materials in the trough.

[0045] For each extracted frequency interval, calculate the variance value of its vibration energy. The larger the variance value, the greater the fluctuation of the vibration energy in this frequency interval, reflecting the non-uniformity of the material distribution.

[0046] The variance value can be used as a standard to measure the dispersion degree. Generally, materials with a higher dispersion degree show greater fluctuations in vibration energy during the conveying process.

[0047] By putting prefabricated dish samples with known stratification states into the conveying trough, experiments are carried out and the variance values are recorded.

[0048] The calibration test can help establish a correspondence library between the variance value and the actual stratification degree, that is, obtain the quantitative relationship between the variance value and the stratification degree through experimental data. During the experiment, according to different stratification degrees, the corresponding variance values are recorded and their change trends are analyzed.

[0049] The critical variance value determined through the calibration test will be used as the standard to judge whether the dispersion degree is high. When the variance value exceeds this critical value, it is determined that the dispersion degree of the prefabricated dishes is high, indicating that the material distribution is uneven, which may affect the subsequent packaging and heating processes.

[0050] In the dispersion calculation method of the present invention, the vibration acceleration sensor array is combined with vibration spectrum analysis. Through real-time monitoring and calibration tests, the material distribution of prefabricated dishes can be accurately detected and regulated, thereby improving the product consistency and production stability. This not only ensures the taste and quality of prefabricated dishes, but also effectively improves production efficiency, having important practical application value.

[0051] In a possible implementation manner, to ensure the universality of the method, multiple groups of standard samples of the target prefabricated dishes need to be prepared first. The viscosities of these standard samples need to cover the allowable range of the dish process, that is, the viscosities of different samples should be representative and can reflect the actual process state of prefabricated dishes in different situations.

[0052] By selecting standard samples with different viscosities, the comprehensiveness and reliability of the test data can be ensured, and the measured reference time can be ensured to be applicable to the production process in different situations.

[0053] Conduct a weighing test on each group of standard samples and record the change in each weighing value. During the experiment, the system will continuously record the change in each weighing value until the weighing value reaches a stable state. The purpose of this step is to measure the time when the material is stably filled into the container under certain conditions.

[0054] During the experiment, abnormal fluctuations in some data may occur due to external factors (such as temperature fluctuations, equipment vibrations, etc.). Therefore, the weighing data needs to be processed to eliminate abnormal values. This can ensure that the test data used is accurate and reliable.

[0055] After eliminating the abnormal values, select the time data required for the weighing value to reach a stable state, and take the median of the time distribution as the reference time. The median can effectively reduce the influence of abnormal data on the reference time and ensure that the obtained reference time represents the stable weighing time of the vast majority of samples.

[0056] In the same group of experiments, measure the residual mass on the wall of the weighing container, that is, the mass of the material that adheres to the container wall and fails to fall into the container in time. By recording the residual material mass at different time points through multiple experiments, relevant data on the residual mass can be obtained.

[0057] Combine the T values (i.e., the time required for the weighing to reach stability) at different time points with the corresponding residual mass data to establish a functional relationship between the T value and the residual mass. Through this function curve, the residual mass corresponding to different time points can be predicted.

[0058] When the actual weighing time T is greater than the reference time, the residual mass at this time can be calculated according to the function curve. To compensate for the influence of the residual mass, the compensation amount Q is usually set to 1.1 - 1.3 times the residual mass corresponding to this time point. This calculation method ensures that the error in the weighing process is effectively corrected by compensating for the residues attached to the container wall, thereby improving the accuracy of packaging.

[0059] By accurately determining the reference time and the calculation of the compensation amount Q, the accuracy and consistency in the quantitative packaging process of prefabricated dishes can be effectively improved. At the same time, the production process is optimized, manual intervention is reduced, and production efficiency is increased. This method has important application value and commercial significance in actual production.

[0060] In a possible implementation, a torque sensor is installed on the drive shaft of the scraper. This sensor can measure in real time the rotational resistance torque generated by the scraper during rotation. The magnitude of the resistance torque reflects the frictional force and adhesive force between the scraper and the container wall, and is a key parameter for judging whether the prefabricated dish material can smoothly separate from the container wall.

[0061] According to the contact area between the scraper and the container wall and the helix angle, the peeling resistance per unit area can be calculated. This step combines the torque value obtained by the sensor with the geometric parameters of the scraper (such as the contact area, helix angle, etc.), and through a certain conversion formula, the peeling resistance torque per unit area is obtained. This helps to quantify the physical characteristics of the peeling process and further guide the adjustment of temperature and force.

[0062] Through the adhesion calibration test, a critical value - that is, the critical resistance of the peeling resistance - can be determined. This critical value is measured in the test for specific prefabricated dish materials and container wall materials. When the actual peeling resistance exceeds this critical value, it means that the driving force of the scraper is not sufficient to complete the peeling process smoothly, which may affect the packaging accuracy or cause low production efficiency.

[0063] When it is detected that the peeling resistance exceeds the critical value, the heating film inside the scraper will be activated. The function of the heating film is to increase the temperature of the target food material, so that its main adhesion components (such as starch or protein) undergo physical changes, reduce their viscosity, reduce the adhesive force, and thus reduce the resistance of the scraper.

[0064] The temperature setting of the heating film is very crucial. It needs to be controlled within a specific range, usually to keep the viscosity reduction rate of the target food material in the range of 30% - 50%. The selection of this temperature range is determined according to the physical characteristics of different prefabricated dishes, especially the nature of their adhesion components (such as starch or protein). Heating within this range can not only effectively reduce the peeling resistance but also ensure that the quality of the food material is not damaged during the heating process.

[0065] Through precise peeling resistance detection and temperature regulation logic, the packaging process of pre-made dishes is effectively optimized. This technology improves the automation level of the production process, reduces waste, and significantly enhances the stability of the production line and packaging quality by increasing the peeling efficiency of the scraper, reducing energy consumption, and adapting to the characteristics of different food ingredients.

[0066] In a possible implementation, first, through peeling tests, for different resistance values (i.e., different adhesion forces), the optimal pitch value that minimizes the residue amount under this condition is measured. The change in pitch directly affects the contact area between the scraper and the container wall, thus affecting the peeling effect. By systematically testing and recording the relationship between pitch and residue amount under different resistances, an accurate peeling resistance - pitch relationship model can be established. This model can accurately describe the optimal value of pitch adjustment under different peeling resistance conditions.

[0067] When the peeling resistance is detected during the packaging process, this value is input into the established resistance - pitch relationship model in real time. The model outputs the corresponding dynamic pitch instruction according to the input peeling resistance. This instruction guides the scraper to adjust the pitch to ensure that the pitch size can minimize the food residue and improve the peeling efficiency during each peeling. Dynamically adjusting the pitch can automatically adjust according to the actual situation, not only improving the peeling efficiency but also ensuring the consistency of product quality.

[0068] During the packaging process, as the peeling resistance increases, the linear velocity needs to be adjusted. To ensure that the scraping force of the scraper does not become too large and cause damage to the food ingredients or equipment, the present invention designs a method in which the linear velocity decreases according to an inverse proportional function. Specifically, when the peeling resistance is detected to increase, the linear velocity decreases according to an inverse proportional function, that is, the greater the resistance, the slower the linear velocity. This can ensure that the scraping force of the scraper is kept constant within a preset safe range and will not cause excessive scraping force due to too high a speed, resulting in damage or over-compression of the food ingredients, and ensuring that the appearance and quality of the pre-made dishes are not affected.

[0069] By dynamically adjusting the pitch and linear velocity and adjusting the scraper movement trajectory according to the change in peeling resistance, it can not only effectively optimize the peeling effect and reduce residues, but also protect the food ingredients while ensuring a constant scraping force, improving the automation level, packaging accuracy, and production efficiency of the production line. This technical feature makes the entire quantitative packaging process of pre-made dishes more intelligent and efficient, more adaptable, and ensures the stability of product quality.

[0070] In a possible implementation, first, a representative set of pre-made food samples is selected. To ensure the broad applicability of the experimental results, the viscosities of these samples should vary in a gradient, that is, the viscosities of the samples are different in different regions. The variation in viscosity makes the peeling resistance uneven during the packaging process, which can simulate different situations that may be encountered in actual production, thus obtaining more practically significant results.

[0071] After the samples are selected, the rheological property parameters of these pre-made foods need to be measured. Rheological properties include viscosity, shear stress, shear rate, etc. The rheological parameters of each sample are obtained through a dedicated rheological instrument (such as a rotational rheometer). These parameters can reflect the relationship between the flow characteristics and stress response of pre-made foods during the packaging process, providing the necessary input data for subsequent modeling.

[0072] Next, a weighing test is carried out under the same environmental conditions. By loading the pre-made food into a container and peeling it in a standard environment, the T value generated during the packaging process is recorded. The T value is an important parameter reflecting the kinetic characteristics during the peeling process, which is usually determined by the movement trajectory, speed, and contact method of the scraper. During the test, the residual mass on the container wall for each test is synchronously recorded, that is, the mass of the unpeeled food remaining during the packaging process.

[0073] Using the rheological property parameters as intermediate variables, combined with the T values and corresponding residual mass data under different experimental conditions, the functional relationship between the T value and the residual mass is fitted by the polynomial regression method. Polynomial regression can accurately capture the non-linear relationship between the T value and the residual mass and provide predictive ability under different conditions through the regression equation. This regression equation enables the corresponding residual mass to be calculated by the measured T value in actual operation, thus realizing the refined control of the peeling process.

[0074] By establishing the functional relationship between the T value and the residual mass, the accurate control of the residual amount during the packaging process can be achieved, optimizing the peeling process, improving the packaging accuracy and efficiency, reducing material waste, enhancing the automation level and production consistency, and thus effectively improving the packaging quality and production efficiency of pre-made foods.

[0075] In a possible implementation, before determining the critical resistance, first, the high-adhesion components of the target pre-made food need to be prepared, such as thickened soup or other ingredients with high adhesion and easy to adhere to the container wall. The standardized samples of these components should be representative and accurately simulate the flow characteristics of high-adhesion ingredients in actual production. The preparation process needs to ensure the consistency of the samples, including key parameters such as concentration and viscosity, so as to obtain reliable data in subsequent experiments.

[0076] Next, during the experiment, the scraper peeling test was carried out under different temperature conditions. Temperature has a significant impact on the adhesion and fluidity of food ingredients. Therefore, it is necessary to measure the minimum starting force when scraping and peeling samples at multiple temperature points. The minimum starting force refers to the minimum force required for the scraper to start peeling the food ingredients, which can reflect the magnitude of the adhesion force between the food ingredients and the container wall. By measuring at different temperatures, the starting force of this food ingredient under different environmental conditions can be obtained, providing the necessary basic data for subsequent calculation of the critical resistance.

[0077] Multiply the measured minimum starting force by a pre-determined safety factor to obtain the critical resistance. The safety factor is an adjustment parameter used to ensure operational stability and safety. This safety factor is determined through the durability test of the scraper material. The durability test mainly evaluates the wear and corrosion resistance of the scraper in different usage environments, ensuring that the scraper material can still maintain good performance under long-term and high-load working conditions.

[0078] The determination of the safety factor is obtained through the long-term use test of the scraper. This test will examine the wear resistance, corrosion resistance, and possible fatigue damage of the scraper material under long-term use. Through this test, a safety factor applicable to this scraper material can be determined, which is used to adjust the calculated critical resistance, thus ensuring the safety and stability of the equipment during the peeling process.

[0079] By determining the critical resistance, the accuracy and reliability of the scraper peeling are effectively improved, providing scientific technical support for the quantitative packaging of prefabricated dishes, ensuring the stability and efficiency of the packaging process, optimizing the design of production equipment, and ultimately improving production efficiency and reducing costs.

[0080] In a possible implementation, first, select appropriate main components (such as starch, oil, salt, seasonings, etc.) according to the typical soups actually used in prefabricated dishes (such as soy sauce soup, thickened soup, bone soup, etc.), and prepare them at different concentration gradients (for example, 1%, 2%, 5%, 10%, 15%, etc.), ensuring that the concentration range covers all possible variations in actual production. Each concentration sample needs to be fully stirred evenly to ensure consistent component distribution, so that the subsequent test data is representative.

[0081] Place the soup samples of each concentration in a colorimetric cuvette of a unified specification, and use a standardized lighting device (such as an LED white light source or a light source with a specific wavelength) for transmittance testing. It is recommended to use a spectrophotometer or a high-precision photoelectric sensor as the measuring device to measure the transmittance of the soup at a specific wavelength (such as 600 nm). The test environment needs to maintain a constant light source intensity, background reflectance, and sample thickness to ensure the comparability and repeatability of the data.

[0082] Using the suspension method under Archimedes' principle, by injecting a known volume of soup into a hydrometer and observing its floating position, or using a more advanced vibrating tube densitometer, the density of each concentration of soup is measured. This method can effectively cope with the interference of factors such as suspended particles and oils in the soup on volume measurement, ensuring accurate density values.

[0083] Pair the light transmittance value of each soup sample with its corresponding density value to form a set of basic data pairs. Then, with light transmittance as the input and density as the output, a light transmittance-density lookup table is established. To adapt to non-standard light transmittance values that may occur in actual production, interpolation algorithms (such as Lagrange interpolation) need to be further used to achieve rapid lookup of the density corresponding to any light transmittance value.

[0084] The constructed lookup table can be pre-stored in the packaging control system and integrated with the data acquisition module of the photoelectric sensor. After real-time acquisition of the light transmittance data of the soup, its density can be quickly deduced by looking up the table, providing a basis for quantitative filling or classification packaging.

[0085] Through standardized sample preparation, optical measurement, precise density testing, and interpolation lookup table algorithms, not only the rapid identification of complex fluid states is achieved, but also the core technical support is provided for the quantitative packaging system of prefabricated dishes, significantly improving the intelligent and automated levels.

[0086] Correspondingly, the embodiment of the present invention also provides a prefabricated dish quantitative packaging device for implementing a prefabricated dish quantitative packaging method described in the embodiment of the present invention, including the following modules: Dynamic pre-dehydration module, including: Optical sensing unit, composed of a light source array and an optical sensor array. The light source irradiates the liquid leakage area at the end of the conveyor belt at a preset incident angle, and the sensor collects the light transmittance distribution data; Processing unit, connected to the optical sensing unit, calculates the mass of soup loss according to the light transmittance distribution gradient, and generates a control instruction based on the dehydration threshold; Execution unit, including an inclination servo motor and a conveyor belt frequency converter, receives the control instruction of the processing unit, and synchronously adjusts the inclination and speed of the conveyor belt; Anti-stratification conveying module, connected to the output end of the dynamic pre-dehydration module through a material channel, including: Vibration analysis unit, composed of an acceleration sensor array installed outside the U-shaped conveying trough, collects the vibration spectrum of the trough body; Dispersion calculation unit, connected to the vibration analysis unit, extracts the energy variance value in the characteristic frequency interval and outputs the dispersion level; Amplitude regulation unit, including a linear vibration motor and a driver, receives the dispersion level signal, and outputs an amplitude control signal that is inversely linked to the dispersion level; The delay compensation weighing module is connected to the output end of the anti-stratification conveying module through a blanking conduit and includes: A weighing sensor unit that collects the mass data of the weighing container in real time; A stabilization time detection unit, connected to the weighing sensor unit, which identifies the time points when the mass data fluctuates less than the threshold value for three consecutive samples and records the duration T; A compensation calculation unit with a pre-stored relationship curve database built-in, which receives the duration T and the dish type code, and outputs a compensation amount Q when T exceeds the reference time; An adaptive peeling module integrated on the inner wall of the weighing container, including: A resistance detection unit composed of a torque sensor and a contact area calculator, which outputs the peeling resistance value in real time; A temperature control unit, including a heating film built into the scraper and a temperature sensor, which receives the peeling resistance value and starts heating to the target temperature when the resistance exceeds the critical value; A motion control unit, connected to the resistance detection unit, generates the linear velocity and pitch commands of a spiral trajectory according to the real-time peeling resistance value, and drives the scraper servo motor.

[0087] The present invention covers any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of the present invention. For the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention. However, those skilled in the art can fully understand the present invention without the description of these details. In addition, well-known methods, processes, procedures, components, and circuits are not described in detail to avoid unnecessary confusion to the essence of the present invention.

[0088] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for quantitatively packaging prefabricated dishes, characterized in that, It includes the following steps: Step 1: Dynamic pre-dehydration. Place the prefabricated dish with soup in a filter hole conveyor belt with adjustable inclination angle. Real-time detect the soup loss amount through optical sensing, and dynamically adjust the conveyor belt inclination angle and speed based on a preset dehydration threshold; Step 2: Anti-stratification conveying. Import the pre-dehydrated dishes into a vibrating conveying trough with a guide structure on the inner wall. Calculate the component dispersion degree by analyzing the vibration energy distribution of the ingredients, and adjust the vibration amplitude in real time accordingly; Step 3: Delayed compensation weighing. Import the conveyed dishes into a weighing container, record the time T when the weighing value reaches stability. When T exceeds the reference time corresponding to the dish type, calculate the compensation amount Q based on the T value and add it to the weighing value; Step 4: Adaptive peeling. Unfold a flexible scraper on the inner wall of the weighing container, real-time detect the peeling resistance between the scraper and the ingredients, and adjust the temperature of the scraper and the linear speed and pitch of the spiral movement trajectory according to the resistance value.

2. The method for quantitatively packaging prefabricated dishes according to claim 1, wherein, The detection method of the soup loss amount in Step 1 is as follows: Set a light source and an optical sensor array below the end of the conveyor belt. The light source irradiates the seepage flow at a preset incident angle; Obtain the light transmittance data of each sensor unit, and calculate the liquid flow cross-sectional area according to the light transmittance distribution gradient; Combine the conveyor belt speed and the preset soup density-light transmittance mapping table to calculate the mass of the lost soup per unit time; The setting method of the dehydration threshold is as follows: Conduct multiple solid-liquid separation cooking experiments on the target prefabricated dish, determine the maximum allowable soup loss rate corresponding to the best taste by sensory evaluation, and take 75%-90% of this loss rate as the threshold upper limit.

3. A prefabricated dish quantitative packaging method according to claim 1, characterized in that, The calculation method of the component dispersion degree in Step 2 is as follows: Install a vibration acceleration sensor array outside the conveying trough to collect the vibration spectra at different positions of the trough body; Extract the characteristic frequency intervals corresponding to the components with density differences in the spectrum, and calculate the variance value of the vibration energy in each interval; When the variance value exceeds the critical variance determined through the calibration test, determine that the dispersion degree is high; The calibration test includes: Putting prefabricated dish samples with known stratification states into the conveying trough, and establishing a correspondence library between the variance value and the actual stratification degree.

4. A prefabricated dish quantitative packaging method according to claim 1, characterized in that, The determination method of the reference time in Step 3 is as follows: Prepare multiple groups of standard samples of the target prefabricated dish, and their viscosities cover the process allowable range of this dish; Conduct a weighing test on each group of samples, record the time when the weighing value reaches stability, and take the median of the time distribution as the reference time after removing the outliers; The calculation method of the compensation amount Q is as follows: Measure the residual mass on the weighing container wall in the same experiment, and establish a functional relationship between the T value and the residual mass; When T is greater than the reference time, take 1.1-1.3 times of the residual mass on the function curve corresponding to this T value as the Q value.

5. A method for quantitatively packaging prefabricated dishes according to claim 1, characterized in that, The detection method of the peeling resistance in Step 4 is as follows: Install a torque sensor on the scraper drive shaft to real-time collect the rotation resistance moment of the scraper; Convert it into the peeling resistance per unit area according to the contact area between the scraper and the container wall and the spiral lead angle; The temperature adjustment logic is as follows: When the peeling resistance exceeds the critical resistance determined through the adhesion force calibration test, start the internal heating film of the scraper; The heating temperature is set to the temperature value that makes the viscosity reduction rate of the main adhesion components of the target ingredients in the range of 30%-50%.

6. A prefabricated dish quantitative packaging method according to claim 1, characterized in that When adjusting the scraper temperature, the linear velocity and pitch of the spiral motion trajectory according to the resistance value in Step 4, the specific pitch adjustment method is as follows: Establish a correspondence model between the peeling resistance and the optimal pitch: Measure the pitch value that minimizes the residue under different resistances through peeling tests; Input the detected peeling resistance into the model in real time and output a dynamic pitch command; The adjustment method for the linear velocity is as follows: When the peeling resistance increases, the linear velocity decreases according to an inverse proportional function to ensure that the scraping force is constantly within a preset safe range.

7. A method for quantitatively packaging prefabricated dishes according to claim 4, wherein, The method for establishing the functional relationship between the T value and the residual mass is as follows: Select prefabricated vegetable samples with a gradient change in viscosity and measure their rheological characteristic parameters; Conduct a weighing test under the same environmental conditions and synchronously record the T value and the residual mass on the container wall; Using the rheological characteristic parameters as an intermediate variable, fit a polynomial regression equation between the T value and the residual mass.

8. A method for quantitatively packaging prefabricated dishes according to claim 5, characterized in that, The method for determining the critical resistance is as follows: Prepare a standardized sample of the highly adhesive component of the target prefabricated vegetable; Measure the minimum starting force for the scraper to peel the sample at different temperatures; Take the product of the minimum starting force and the safety factor as the critical resistance, and the safety factor is determined through the durability test of the scraper material.

9. A method for quantitatively packaging prefabricated dishes according to claim 2, characterized in that, The method for constructing the soup density-transmittance mapping table is as follows: Prepare simulated soups with different concentrations and measure their transmittance under a standard light environment; Precisely measure the density of each concentration of soup using the suspension method; Establish a transmittance-density lookup table and implement density query corresponding to any transmittance through an interpolation algorithm.

10. A prefabricated dish quantitative packaging device for performing a prefabricated dish quantitative packaging method according to any one of claims 1-9, characterized in that, It includes the following modules: Dynamic pre-dehydration module, including: Optical sensing unit, composed of a light source array and an optical sensor array. The light source irradiates the liquid seepage area at the end of the conveyor belt at a preset incident angle, and the sensor collects the transmittance distribution data; Processing unit, connected to the optical sensing unit, calculates the mass of the soup lost according to the transmittance distribution gradient, and generates a control command based on the dehydration threshold; Execution unit, including an inclination servo motor and a conveyor belt frequency converter, receives the control command from the processing unit and synchronously adjusts the inclination and speed of the conveyor belt; Anti-stratification conveying module, connected to the output end of the dynamic pre-dehydration module through a material channel, including: Vibration analysis unit, composed of an acceleration sensor array installed on the outside of the U-shaped conveying trough, which collects the vibration spectrum of the trough body; Dispersion calculation unit, connected to the vibration analysis unit, extracts the energy variance value in the characteristic frequency range and outputs the dispersion level; Amplitude control unit, including a linear vibration motor and a driver, receives the dispersion level signal and outputs an amplitude control signal that is inversely linked to the dispersion level; Delay compensation weighing module, connected to the output end of the anti-stratification conveying module through a blanking conduit, including: Weighing sensor unit, which collects the mass data of the weighing container in real time; Stable time detection unit, connected to the weighing sensor unit, identifies the time point when the mass data fluctuates less than the threshold for three consecutive samplings and records the duration T; Compensation calculation unit, with a pre-stored relationship curve database built-in, receives the duration T and the dish type code, and outputs a compensation amount Q when T exceeds the reference time; Adaptive peeling module, integrated on the inner wall of the weighing container, including: Resistance detection unit, composed of a torque sensor and a contact area calculator, which outputs the peeling resistance value in real time; The temperature control unit includes a heating film built into the squeegee and a temperature sensor, receives the peeling resistance value, and starts heating to the target temperature when the resistance exceeds the critical value; The motion control unit is connected to the resistance detection unit, generates the linear velocity and pitch commands of the spiral trajectory according to the real-time peeling resistance value, and drives the squeegee servo motor.

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