Manufacturing method of packaging container based on 3D printing

Abstract

The present invention belongs to the field of 3D printing and intelligent manufacturing technology, and proposes a manufacturing method for packaging containers based on 3D printing, specifically: obtaining a three-dimensional model of the packaging container filling material, recording the three-dimensional model as a buffer body printing model; then importing the buffer body printing model into the finite element analysis software to read the stress; then quantifying the risk of structural weakening according to the buffer body printing model and its stress distribution; finally, reinforcing the position where the stress defect exists in the packaging container through the weakening risk. The present invention analyzes the three-dimensional model of the packaging container filling material in the 3D printing scene using the heterogeneous filling technology, and efficiently quantifies the risk of structural fatigue failure generated under the heterogeneous filling technology by combining the model and its stress distribution, and reinforces the position of the stress defect of the packaging container according to the risk, thereby effectively improving the stability of the double-layer packaging structure.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printing and intelligent manufacturing, and in particular relates to a manufacturing and molding method of a packaging container based on 3D printing. Background Art

[0002] The main function of packaging containers is to protect and transport products. With the gradual popularization of intelligent manufacturing, the demand for high-performance production equipment and instruments is increasing, and the number of external outputs is huge. The packaging containers involved are crucial to high-performance production equipment. At present, the packaging containers for high-performance production equipment in this field advocate a double-layer packaging structure that combines inner and outer packaging. The outer packaging resists external pressure and damage risks, and the inner packaging ensures the safety of the instrument, thereby improving the safety of external high-performance production equipment. Cushioning materials need to be filled between the outer and inner packaging. The filling materials not only provide additional cushioning effects, but also effectively isolate the product from the external environment to prevent the influence of moisture, dust and other pollutants. The use of 3D printing technology to manufacture filling materials can customize fillers with complex shapes and unique structures according to specific product requirements, and can be flexibly adjusted according to the shape and size of the product to achieve the best protection effect.

[0003] In the process of manufacturing the filling material in the double-layer packaging structure using 3D printing technology, since the application scenario of the double-layer packaging involves transportation requirements, the preference for low packaging weight is recommended. Therefore, it is recommended to use a non-homogeneous filling method for 3D printing. This is because the non-homogeneous filling method uses the method of autonomously defining the printing path and optimizing the filling density to achieve non-homogeneous and complex filling inside the printed product, thereby reducing the weight of the component without affecting the structural strength. However, transportation scenarios are usually accompanied by a large amount of vibration, which is often ignored in the non-homogeneous filling method. These vibrations are likely to cause the risk of fatigue failure of some structures and destroy the stability of the double-layer packaging structure, thereby causing the packaging container to lose its protective effect on the product or transported object. Therefore, a manufacturing method for packaging containers based on 3D printing is urgently needed to effectively identify and process the risk of structural fatigue failure generated by non-homogeneous filling technology. Summary of the invention

[0004] The purpose of the present invention is to propose a manufacturing method for a packaging container based on 3D printing to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0005] In order to achieve the above object, according to one aspect of the present invention, a manufacturing method of a packaging container based on 3D printing is provided, the method comprising the following steps:

[0006] Obtain a three-dimensional model of the filling material of the packaging container, record the three-dimensional model as the buffer body printing model, import the buffer body printing model into the finite element analysis software to read the stress, quantify the structural weakening risk according to the buffer body printing model and its stress distribution, and reinforce the locations where stress defects exist in the packaging container according to the weakening risk.

[0007] Furthermore, a three-dimensional model of the filling material of the packaging container is obtained, and the method of recording the three-dimensional model as the buffer body printing model is as follows: the packaging container includes an outer packaging, an inner packaging and a filling material, and the filling material fills the space area between the outer packaging and the inner packaging; the three-dimensional model corresponding to the filling material is read from the three-dimensional design software and recorded as the buffer body printing model.

[0008] The 3D design software includes SolidWorks or Rhino. The non-homogeneous filling method is set in the Cura slicing software; the purpose of using the non-homogeneous filling method is to reduce the amount of filling material used, that is, to reduce the overall weight of the printed product of the buffer body printing model.

[0009] Furthermore, a method for importing the printed model of the buffer body into the finite element analysis software to read the stress is: importing the printed model of the buffer body into the ANSYS finite element analysis software to perform stress simulation analysis to obtain a stress cloud map, wherein the finite element analysis steps include model import, mesh division, and mesh attribute definition; setting filling material parameters, geometric properties, boundary conditions, and load conditions, wherein the load conditions; obtaining a stress cloud map by solving the finite element analysis software, and obtaining the stress at each position from the stress cloud map.

[0010] Furthermore, the method for quantifying the risk of structural weakening based on the buffer body printing model and its stress distribution is:

[0011] Suppose the corner point set of each corner point of the buffer printing model is V, V = {v0, v1, v2...v i …v N}, v0 corner point is the corner point of the buffer printing model with the shortest distance from the origin of the three-dimensional coordinate system, i = [1, N], N is the number of corner points in the buffer printing model, v i is the i-th corner point of the buffer body printing model; the coordinate of the origin is (0,0,0); the order of the corner points is arranged according to the distance from the origin of the three-dimensional coordinate system;

[0012] Calculate any corner point v i The shortest distance to the outer packaging and the shortest distance to the inner packaging are recorded as the outer point distance difference Opic and the inner point distance difference Ipic respectively. If the corner point v i If the outer point distance difference is greater than the inner point distance difference, then the corner point v i Define as the first built-in contact, let the set of the first built-in contacts be VA;

[0013] In VA, any first built-in contact is taken as the current built-in contact, and the other first built-in contacts are the adjacent first built-in contacts. x and v y are the first adjacent built-in contacts closest to and farthest from the current built-in contact, respectively, v x to v y The midpoint of is the second built-in contact v corresponding to the current built-in contact r ;

[0014] Let the set of the second built-in contacts be VB, VB = {v0, v1, v2…v r …v M}, r∈[1,M], M is the number of the second built-in contacts in VB, v r is the rth second built-in contact of VB;

[0015] For any built-in contact in VB, obtain the other second built-in contact with the shortest distance, and connect the two points to form an edge recorded as the risk built-in edge, and define the set of risk built-in edges as EB; obtain the maximum stress value on any risk built-in edge and record it as the overflow characteristic value of the risk built-in edge, and the shortest distance between the point corresponding to the overflow characteristic value and the outer packaging and the shortest distance between the point and the inner packaging are recorded as the outer distance difference and the inner distance difference respectively; calculate the average value of the overflow characteristic values ​​of all risk built-in edges in the set EB and record it as the overflow base value Incp; in each position in the buffer body printing model that is in direct contact with the inner packaging, the maximum value of the corresponding stress value is recorded as the inner layer stress peak value;

[0016] If there is a risk built-in edge in the set EB whose overflow characteristic value is greater than the overflow base value, the risk built-in edge is defined as a risk mitigation edge. The ratio of the overflow characteristic value to the inner layer stress peak value of each risk mitigation edge is calculated and recorded as the overflow risk value Oris. The risk bearing value Rova of the risk mitigation edge is calculated based on the overflow risk value. The calculation method is:

[0017]

[0018] Where k is the serial number of the risk mitigation edge, i1 is the cumulative variable, Rova(k) is the risk pressure value of the kth risk mitigation edge, Opic i1 and Ipic i1 They are the outer point distance difference and inner point distance difference of the second built-in contact of the i1th point, Oris k is the spillover risk value of the kth risk mitigation edge, Opic k and Ipic k are the outer distance difference and inner distance difference corresponding to the kth risk mitigation edge respectively.

[0019] Since the weakening risk is calculated through the stress distribution after finite element analysis, and the risk mitigation edge is obtained based on the stress at each position of the buffer body printing model and the numerical calculation in the three-dimensional coordinate system, it can effectively quantify the structural fatigue failure risk caused by the non-homogeneous filling technology in the three-dimensional model, thereby providing effective data support for the consolidation step of the weakening risk position. However, since the recognition of low stress values ​​is ignored in the calculation and acquisition of the risk mitigation edge, the data sensitivity is too large at the position where the stress value is small, which further causes the risk bearing value of the risk mitigation edge to be over-quantified, resulting in the problem of distortion of the quantization function. However, the existing technology cannot effectively compensate for this distortion phenomenon. In order to eliminate this influence, the present invention proposes a more preferred solution as follows.

[0020] Preferably, the method for quantifying the risk of structural weakening according to the buffer body printing model and its stress distribution is: constructing a cutting plane in the buffer body printing model, and each cutting plane constitutes an assembly cutting set; recording that the stress value corresponding to the intersection of any cutting plane in the assembly cutting set and the three-dimensional model constitutes a first stress set Str_Fs, the coefficient of variation corresponding to the first stress set on the plane is Var_K, and the average value of the coefficient of variation corresponding to the first stress set on the assembly cutting set is the variation mean Ave_Var;

[0021] The intersection of the cutting plane equation and the three-dimensional model refers to each grid where the cutting plane and the buffer body printing model overlap under the finite element analysis, and the first stress set is the set of stress values ​​obtained from each grid;

[0022] When the coefficient of variation corresponding to the first stress set of the cutting plane is greater than the mean value of variation, it is defined as a sub-cutting plane, and the intersection of any sub-cutting plane and the inner packaging contour is the sub-cutting point set Str_Sc;

[0023] The inner packaging contour refers to any mesh in the buffer body printing model that contacts the inner packaging. It is defined that when the obtained mesh coincides with the sub-cutting surface, the mesh is the intersection of the sub-cutting surface and the inner packaging contour;

[0024] The polyfit function is used to fit the sub-cut point set Str_Sc to obtain the original marginal function. The points corresponding to the extreme values ​​of the original marginal function constitute the third stress set Str_Th, where the extreme values ​​are obtained by differentiation. The points in the third stress concentration are connected in sequence according to the x-coordinates arranged in ascending order, and finally the starting point and the end point are connected to form a polygon. The center of gravity of the polygon is the stress defect point; all stress defect points on all sub-cut surfaces constitute the defect point set Str_Fo, and the straight line between any two points in the defect point set is calculated to constitute the stress edge set Str_Dis. The minimum spanning tree of the defect point set and the stress edge set is solved by the Prim algorithm, so that all stress defect points are connected at least once in the spanning tree, and the shortest path connecting all points in the defect point set is solved to constitute the risk mitigation edge set, that is, the risk mitigation edge set is the stress edge set with the smallest sum of the Euclidean distances of all stress defect points in series; the elements in the risk mitigation edge set are risk mitigation edges; through the risk mitigation edges, the structural weakening risk Str_risk is calculated:

[0025]

[0026] Where exp is an exponential function with the natural constant e as the base, Ave_Str is the stress mean of all points on the risk mitigation edge, and the coordinates of the two stress defect points on the risk mitigation edge are s. i =(x i ,y i ,z i ),s j =(x j ,y j ,z j ),Var_Ks i ,Var_Ks j is the coefficient of variation of the first stress set of two stress defect points on their corresponding sub-cut surfaces, and OUDis is the Euclidean distance between the two stress defect points.

[0027] The Euclidean distance calculation method is: The Prim algorithm is called through the scipy package in Python, and the polyfit function is called through the numpy package in Python; when Var_Ks i or Var_Ks j If there are multiple values, the maximum value is taken for calculation.

[0028] Furthermore, a method of constructing cutting planes in the buffer body printing model and forming an assembly cutting set with each cutting plane is as follows: for the buffer body printing model, a point with a stress value of zero is selected at its bottom layer as the origin O, and a Cartesian rectangular coordinate system O-xyz is made with the origin O, the x-axis, y-axis and z-axis represent the three orthogonal directions of the model respectively, and the maximum and minimum values ​​of the points on the model on the z-axis are MA_Z and MI_Z respectively, and the parallel plane bundle parallel to the XOY plane is the first cutting plane set Cut_Fs, Where f_XOY(K i ) represents the first cutting plane set z value is K i The parallel plane bundle parallel to the x-y=0 plane is the second cutting plane set Cut_Sc, Where f_XMY(C i ) represents the second cutting plane set x-y=C i plane; define the parallel plane bundle parallel to the -x+y=0 plane as the third cutting plane set Cut_Th, Where f_MXY(D i ) represents the third cutting plane set y-x=C i plane; construct the union of Cut_Fs, Cut_Sc and Cut_Th sets as the total cutting set Cut_Sum.

[0029] Each element in the assembly cutting set is a cutting plane.

[0030] Furthermore, the method for reinforcing the position where the stress defect exists in the packaging container by weakening the risk is: if the risk mitigation edge does not pass through the space area of ​​the inner packaging, it is defined as a risk marking line, otherwise it is defined as a reference marking line; the value range of each structural weakening risk corresponding to the reference marking line is obtained and recorded as Z.RRSK; if the structural weakening risk of a risk marking line exceeds Z.RRSK, the risk marking line is defined as the first type of risk marking line;

[0031] The vibration fatigue measurement interval VMI is preset, VMI∈(0,1] hours, the maximum bearing capacity of the printing material to be used in the buffer body printing model is P, and the maximum stress that the material can withstand before failure is S;

[0032] Within the VMI interval, a vibration load in the interval (0, P) is applied to the buffer body printing model every 0.1 milliseconds, and the real-time stress RS of the dynamic response of each point of the model is recorded. If the real-time stress RS of any point in the VMI interval is greater than or equal to P, then the point is recorded as the fatigue failure point of the buffer body printing model; if the risk mitigation edge contains a fatigue failure point, it is defined as a second-class risk marking line; the first-class risk marking lines and the second-class risk marking lines are recorded as high-risk marking lines, and the remaining risk marking lines are low-risk marking lines; the slices where the high-risk marking lines are located are reinforced: each slice that intersects with any high-risk marking line is identified from the Cura slicing software, and the uniform filling method is used to fill these slices, and the preset non-homogeneous filling method is used for the remaining slices.

[0033] Preferably, all undefined variables in the present invention, if not clearly defined, can be manually set thresholds.

[0034] The present invention also provides a manufacturing and forming system for packaging containers based on 3D printing, the manufacturing and forming system for packaging containers based on 3D printing comprising: a processor, a memory, and a computer program stored in the memory and executable on the processor, the processor implementing the steps in the manufacturing and forming method for packaging containers based on 3D printing when executing the computer program, the manufacturing and forming system for packaging containers based on 3D printing can be run in computing devices such as desktop computers, laptop computers, PDAs, and cloud data centers, the executable systems may include, but are not limited to, processors, memories, and server clusters, the processor executing the computer program runs in the following system units:

[0035] A model acquisition unit, used to acquire a three-dimensional model of the filling material of the packaging container, and record the three-dimensional model as a buffer body printing model;

[0036] A stress reading unit, used to import the buffer body printing model into the finite element analysis software to read the stress;

[0037] A risk quantification unit, used to quantify the risk of structural weakening based on the buffer body printing model and its stress distribution;

[0038] The reinforcement processing unit is used to reinforce the position where stress defects exist in the packaging container by weakening the risk.

[0039] The beneficial effects of the present invention are as follows: the present invention provides a manufacturing method for packaging containers based on 3D printing, by analyzing the three-dimensional model of the packaging container filling material in the 3D printing scene using the heterogeneous filling technology, combining the model and its stress distribution to efficiently quantify the risk of structural fatigue failure generated under the heterogeneous filling technology, and reinforce the position of the stress defect of the packaging container according to the risk, thereby effectively improving the stability of the double-layer packaging structure. Especially in the transportation scene accompanied by a lot of vibration, it can avoid the negative impact of the packaging container caused by structural fatigue failure to a greater extent, which is specifically the damage to the integrity of the inner packaging and the transported items, thereby ensuring the protective effect of the packaging container on the product or transported items. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and other features of the present invention will become more obvious by describing in detail the embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings of the present invention represent the same or similar elements. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work. In the accompanying drawings:

[0041] Figure 1 Shown is a flow chart of a manufacturing method of a packaging container based on 3D printing;

[0042] Figure 2 Shown is a structural diagram of a manufacturing molding system for a packaging container based on 3D printing. DETAILED DESCRIPTION

[0043] The following will be combined with the embodiments and drawings to clearly and completely describe the concept, specific structure and technical effects of the present invention, so as to fully understand the purpose, scheme and effect of the present invention. It should be noted that the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0044] like Figure 1 The flowchart of the manufacturing method of the packaging container based on 3D printing is shown below. Figure 1 The present invention will now be described with reference to a method for manufacturing a packaging container based on 3D printing according to an embodiment of the present invention. The method comprises the following steps:

[0045] Obtain a three-dimensional model of the filling material of the packaging container, record the three-dimensional model as the buffer body printing model, import the buffer body printing model into the finite element analysis software to read the stress, quantify the structural weakening risk according to the buffer body printing model and its stress distribution, and reinforce the locations where stress defects exist in the packaging container according to the weakening risk.

[0046] Furthermore, a three-dimensional model of the filling material of the packaging container is obtained, and the method of recording the three-dimensional model as the buffer body printing model is as follows: the packaging container includes an outer packaging, an inner packaging and a filling material, and the filling material fills the space area between the outer packaging and the inner packaging; the three-dimensional model corresponding to the filling material is read from the three-dimensional design software and recorded as the buffer body printing model.

[0047] Furthermore, a method for importing the printed model of the buffer body into the finite element analysis software to read the stress is: importing the printed model of the buffer body into the ANSYS finite element analysis software to perform stress simulation analysis to obtain a stress cloud map, wherein the finite element analysis steps include model import, mesh division, and mesh attribute definition; setting filling material parameters, geometric properties, boundary conditions, and load conditions, wherein the load conditions; obtaining a stress cloud map by solving the finite element analysis software, and obtaining the stress at each position from the stress cloud map.

[0048] Furthermore, the method for quantifying the structural weakening risk according to the buffer body printing model and its stress distribution is: let the corner point set of each corner point of the buffer body printing model be V, V = {v0, v1, v2...v i …v N}, v0 corner point is the corner point of the buffer printing model with the shortest distance from the origin of the three-dimensional coordinate system, i = [1, N], N is the number of corner points in the buffer printing model, v i Print the i-th corner point of the model for the buffer body;

[0049] Calculate any corner point v i The shortest distance to the outer packaging and the shortest distance to the inner packaging are recorded as the outer point distance difference Opic and the inner point distance difference Ipic respectively. If the corner point v i If the outer point distance difference is greater than the inner point distance difference, then the corner point v i Define as the first built-in contact, let the set of the first built-in contacts be VA;

[0050] In VA, any first built-in contact is taken as the current built-in contact, and the other first built-in contacts are the adjacent first built-in contacts. x and v y are the first adjacent built-in contacts closest to and farthest from the current built-in contact, respectively, v x to v y The midpoint of is the second built-in contact v corresponding to the current built-in contact r ;

[0051] Let the set of the second built-in contacts be VB, VB = {v0, v1, v2…v r …v M}, r∈[1,M], M is the number of the second built-in contacts in VB, v ris the rth second built-in contact of VB;

[0052] For any built-in contact in VB, obtain the other second built-in contact with the shortest distance, and connect the two points to form an edge recorded as the risk built-in edge, and define the set of risk built-in edges as EB; obtain the maximum stress value on any risk built-in edge and record it as the overflow characteristic value of the risk built-in edge, and the shortest distance between the point corresponding to the overflow characteristic value and the outer packaging and the shortest distance between the point and the inner packaging are recorded as the outer distance difference and the inner distance difference respectively; calculate the average value of the overflow characteristic values ​​of all risk built-in edges in the set EB and record it as the overflow base value Incp; in each position in the buffer body printing model that is in direct contact with the inner packaging, the maximum value of the corresponding stress value is recorded as the inner layer stress peak value;

[0053] If there is a risk built-in edge in the set EB whose overflow characteristic value is greater than the overflow base value, the risk built-in edge is defined as a risk mitigation edge. The ratio of the overflow characteristic value to the inner layer stress peak value of each risk mitigation edge is calculated and recorded as the overflow risk value Oris. The risk bearing value Rova of the risk mitigation edge is calculated based on the overflow risk value. The calculation method is:

[0054]

[0055] Where k is the serial number of the risk mitigation edge, i1 is the cumulative variable, Rova(k) is the risk pressure value of the kth risk mitigation edge, Opic i1 and Ipic i1 They are the outer point distance difference and inner point distance difference of the second built-in contact of the i1th point, Oris k is the spillover risk value of the kth risk mitigation edge, Opic k and Ipic k are the outer distance difference and inner distance difference corresponding to the kth risk mitigation edge respectively.

[0056] Preferably, the method for quantifying the risk of structural weakening according to the buffer body printing model and its stress distribution is: constructing a cutting plane in the buffer body printing model, and each cutting plane constitutes an assembly cutting set; recording that the stress value corresponding to the intersection of any cutting plane in the assembly cutting set and the three-dimensional model constitutes a first stress set Str_Fs, the coefficient of variation corresponding to the first stress set on the plane is Var_K, and the average value of the coefficient of variation corresponding to the first stress set on the assembly cutting set is the variation mean Ave_Var;

[0057] When the coefficient of variation corresponding to the first stress set of the cutting plane is greater than the mean value of variation, it is defined as a sub-cutting plane, and the intersection of any sub-cutting plane and the inner packaging contour is the sub-cutting point set Str_Sc;

[0058] The original marginal function is obtained by fitting the sub-cut point set Str_Sc with the polyfit function. The points corresponding to the maximum and minimum values ​​of the original marginal function constitute the third stress set Str_Th. The points in the third stress concentration are connected in sequence according to the x-coordinates arranged in ascending order. Finally, the starting point and the end point are connected to form a polygon. The center of gravity of the polygon is the stress defect point. All stress defect points on all sub-cut surfaces constitute the defect point set Str_Fo. The Euclidean distance between any two points in the defect point set is calculated to form the stress edge set Str_Dis. The minimum spanning tree of the defect point set and the stress edge set is solved by the Prim algorithm, so that all stress defect points are connected at least once in the spanning tree. The shortest path connecting all points in the defect point set is solved to form a risk mitigation edge set, that is, the risk mitigation edge set is the stress edge set with the smallest sum of the Euclidean distances of all stress defect points in series. Through the risk mitigation edge, the structural weakening risk Str_risk is calculated:

[0059]

[0060] Where exp is an exponential function with the natural constant e as the base, Ave_Str is the stress mean of all points on the risk mitigation edge, and the coordinates of the two stress defect points on the risk mitigation edge are s. i =(x i ,y i ,z i ),s j =(x j ,y j ,z j ),Var_Ks i ,Var_Ks j is the coefficient of variation of the first stress set of two stress defect points on their corresponding sub-cut surfaces, and OUDis is the Euclidean distance between the two stress defect points.

[0061] Furthermore, a method of constructing cutting planes in the buffer body printing model and forming an assembly cutting set with each cutting plane is as follows: for the buffer body printing model, a point with a stress value of zero is selected at its bottom layer as the origin O, and a Cartesian rectangular coordinate system O-xyz is made with the origin O, the x-axis, y-axis and z-axis represent the three orthogonal directions of the model respectively, and the maximum and minimum values ​​of the points on the model on the z-axis are MA_Z and MI_Z respectively, and the parallel plane bundle parallel to the XOY plane is the first cutting plane set Cut_Fs, Where f_XOY(K i ) represents the first cutting plane set z value is K i The parallel plane bundle parallel to the x-y=0 plane is the second cutting plane set Cut_Sc, Where f_XMY(C i ) represents the second cutting plane set x-y=C i plane; define the parallel plane bundle parallel to the -x+y=0 plane as the third cutting plane set Cut_Th, Where f_MXY(D i ) represents the third cutting plane set y-x=C i plane; construct the union of Cut_Fs, Cut_Sc and Cut_Th sets as the total cutting set Cut_Sum.

[0062] Furthermore, the method for reinforcing the position where the stress defect exists in the packaging container by weakening the risk is as follows: if the risk mitigation edge does not pass through the spatial area of ​​the inner packaging, it is defined as a risk marking line, otherwise it is defined as a reference marking line; the value range of each structural weakening risk corresponding to the reference marking line is obtained and recorded as Z.RRSK; if the structural weakening risk of a risk marking line exceeds Z.RRSK, then the risk marking line is defined as the first type of risk marking line; a vibration fatigue measurement interval VMI is preset, VMI∈(0,1] hours, the maximum bearing capacity of the printing material to be used in the buffer body printing model is recorded as P, and the maximum stress that the material can withstand before damage is S; the buffer body is measured every 0.1 milliseconds within the VMI interval. A vibration load in the interval (0, P) is applied to the printed model, and the real-time stress RS of the dynamic response of each point of the model is recorded. If the real-time stress RS of any point in the VMI interval is greater than or equal to P, the point is recorded as the fatigue failure point of the printed model of the buffer body; if the risk mitigation edge contains a fatigue failure point, it is defined as the second-class risk marking line; the first-class risk marking lines and the second-class risk marking lines are recorded as high-risk marking lines, and the remaining risk marking lines are low-risk marking lines; the slices where the high-risk marking lines are located are reinforced: each slice that intersects with any high-risk marking line is identified from the Cura slicing software, and the uniform filling method is used to fill these slices, and the preset non-homogeneous filling method is used for the remaining slices.

[0063] The embodiment of the present invention provides a manufacturing and molding system for a packaging container based on 3D printing, such as Figure 2 What is shown is a structural diagram of a manufacturing and molding system for a packaging container based on 3D printing of the present invention. The manufacturing and molding system for a packaging container based on 3D printing of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned embodiment of the manufacturing and molding method for a packaging container based on 3D printing are implemented.

[0064] The system comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to run in the following units of the system:

[0065] A model acquisition unit, used to acquire a three-dimensional model of the filling material of the packaging container, and record the three-dimensional model as a buffer body printing model;

[0066] A stress reading unit, used to import the buffer body printing model into the finite element analysis software to read the stress;

[0067] A risk quantification unit, used to quantify the risk of structural weakening based on the buffer body printing model and its stress distribution;

[0068] The reinforcement processing unit is used to reinforce the position where stress defects exist in the packaging container by weakening the risk.

[0069] The manufacturing and forming system of the packaging container based on 3D printing can be run in computing devices such as desktop computers, laptops, PDAs and cloud servers. The manufacturing and forming system of the packaging container based on 3D printing can include, but is not limited to, a processor and a memory. Those skilled in the art can understand that the example is only an example of the manufacturing and forming system of the packaging container based on 3D printing, and does not constitute a limitation on the manufacturing and forming system of the packaging container based on 3D printing. It can include more or less parts than the example, or combine certain parts, or different parts. For example, the manufacturing and forming system of the packaging container based on 3D printing can also include input and output devices, network access devices, buses, etc.

[0070] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the operating system of the manufacturing and molding system for packaging containers based on 3D printing, and uses various interfaces and lines to connect various parts of the entire operating system of the manufacturing and molding system for packaging containers based on 3D printing.

[0071] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the manufacturing and forming system of the packaging container based on 3D printing by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0072] Although the description of the present invention has been quite detailed and has been described in particular with respect to several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, so as to effectively cover the intended scope of the present invention. In addition, the present invention is described above with the embodiments foreseeable by the inventors, and its purpose is to provide a useful description, and those non-substantial changes to the present invention that are not currently foreseen may still represent equivalent changes of the present invention.

Claims

1. A method for manufacturing a packaging container based on 3D printing, characterized in that: The method comprises the following steps: obtaining a three-dimensional model of a filling material of a packaging container, recording the three-dimensional model as a buffer body printing model, importing the buffer body printing model into a finite element analysis software to read stress, quantifying the structural weakening risk according to the buffer body printing model and its stress distribution, and reinforcing the position of the packaging container with stress defects according to the weakening risk; The method to quantify the structural weakening risk based on the buffer body printing model and its stress distribution is: let the corner point set of each corner point of the buffer body printing model be V, and calculate any corner point v i The shortest distance to the outer packaging and the shortest distance to the inner packaging are recorded as the outer point distance difference Opic and the inner point distance difference Ipic respectively. If the corner point v i If the outer point distance difference is greater than the inner point distance difference, then the corner point v i Define as the first built-in contact, let the set of the first built-in contacts be VA; In VA, any first built-in contact is taken as the current built-in contact, and the other first built-in contacts are the adjacent first built-in contacts. x and v y are the first adjacent built-in contacts closest to and farthest from the current built-in contact, respectively, v x to v y The midpoint of is the second built-in contact v corresponding to the current built-in contact r ; Let the set of second built-in contacts be VB, M be the number of second built-in contacts in VB, v r is the rth second built-in contact of VB; For any built-in contact in VB, obtain the other second built-in contact with the shortest distance, and connect the two points to form an edge recorded as the risk built-in edge, and define the set of risk built-in edges as EB; obtain the maximum stress value on any risk built-in edge and record it as the overflow characteristic value of the risk built-in edge, and the shortest distance between the point corresponding to the overflow characteristic value and the outer packaging and the shortest distance between the point and the inner packaging are recorded as the outer distance difference and the inner distance difference respectively; calculate the average value of the overflow characteristic values ​​of all risk built-in edges in the set EB and record it as the overflow base value Incp; in each position in the buffer body printing model that is in direct contact with the inner packaging, the maximum value of the corresponding stress value is recorded as the inner layer stress peak value; If there is a risk built-in edge in the set EB whose overflow characteristic value is greater than the overflow base value, the risk built-in edge is defined as a risk mitigation edge. The ratio of the overflow characteristic value to the inner layer stress peak value of each risk mitigation edge is calculated and recorded as the overflow risk value Oris. The risk bearing value Rova of the risk mitigation edge is calculated based on the overflow risk value. The calculation method is: ; Where k is the serial number of the risk mitigation edge, i1 is the cumulative variable, Rova(k) is the risk pressure value of the kth risk mitigation edge, Opic i1 and Ipic i1 They are the outer point distance difference and inner point distance difference of the second built-in contact of the i1th point, Oris k is the spillover risk value of the kth risk mitigation edge, Opic k and Ipic k are the outer distance difference and inner distance difference corresponding to the kth risk mitigation edge respectively.

2. The method for manufacturing a packaging container based on 3D printing according to claim 1, characterized in that: A method of obtaining a three-dimensional model of a filling material of a packaging container and recording the three-dimensional model as a printing model of a buffer body is as follows: the packaging container includes an outer packaging, an inner packaging and a filling material, and the filling material fills a space area between the outer packaging and the inner packaging; The three-dimensional model corresponding to the filling material is read from the three-dimensional design software and recorded as the buffer body printing model.

3. The method for manufacturing a packaging container based on 3D printing according to claim 1, characterized in that: The method of importing the buffer body printing model into the finite element analysis software to read the stress is: importing the buffer body printing model into the ANSYS finite element analysis software to perform stress simulation analysis to obtain the stress cloud map, wherein the finite element analysis steps include model import, mesh division and mesh attribute definition; setting filling material parameters, geometric attributes, boundary conditions, and load conditions; The stress cloud map is obtained by solving the finite element analysis software, and the stress at each position is obtained from the stress cloud map.

4. The method for manufacturing a packaging container based on 3D printing according to claim 1, characterized in that: The method for quantifying the structural weakening risk according to the buffer body printing model and its stress distribution can be replaced by: constructing a cutting plane in the buffer body printing model, and each cutting plane constitutes an assembly cutting set; the stress value corresponding to the intersection of any cutting plane in the assembly cutting set and the three-dimensional model constitutes the first stress set Str_Fs, the coefficient of variation corresponding to the first stress set on the plane is Var_K, and the average value of the coefficient of variation corresponding to the first stress set on the assembly cutting set is the variation mean Ave_Var; When the coefficient of variation corresponding to the first stress set of the cutting plane is greater than the mean value of variation, it is defined as a sub-cutting plane, and the intersection of any sub-cutting plane and the inner packaging contour is the sub-cutting point set; The polyfit function is used to fit the sub-cut point set to obtain the original marginal function. The points corresponding to the extreme values ​​of the original marginal function constitute the third stress set Str_Th. The points in the third stress concentration are connected in sequence according to the x-coordinates arranged in ascending order. Finally, the starting point and the end point are connected to form a polygon. The center of gravity of the polygon is the stress defect point. All stress defect points on all sub-cut surfaces constitute the defect point set Str_Fo. The Euclidean distance between any two points in the defect point set is calculated to form the stress edge set Str_Dis. The minimum spanning tree of the defect point set and the stress edge set is solved by the Prim algorithm, so that all stress defect points are connected at least once in the spanning tree. The shortest path connecting all points in the defect point set is solved to form a risk mitigation edge set, that is, the risk mitigation edge set is the stress edge set with the smallest sum of the Euclidean distances of all stress defect points in series. Through the risk mitigation edge, the structural weakening risk is calculated according to the distance of the stress defect point and the coefficient of variation of the corresponding cutting plane.

5. The method for manufacturing a packaging container based on 3D printing according to claim 4, characterized in that: The method of constructing cutting planes in the buffer body printing model and forming an assembly cutting set with each cutting plane is as follows: for the buffer body printing model, a point with a stress value of zero is selected as the origin O at its bottom layer, and the Cartesian rectangular coordinate system O-xyz is made with the origin O. The x-axis, y-axis and z-axis represent the three orthogonal directions of the model respectively. The maximum and minimum values ​​of the points on the model on the z-axis are MA_Z and MI_Z respectively. The parallel plane bundle parallel to the XOY plane is the first cutting plane set Cut_Fs, Cut_Fs = {f_XOY(K1), f_XOY(K2), …, f_XOY(K n );K i ∈[MI_Z,MA_Z], , i=1,2,…,n-1};where f_XOY(K i ) represents the first cutting plane set z value is K i The parallel plane bundle parallel to the x-y=0 plane is the second cutting plane set Cut_Sc, Cut_Sc={f_XMY(C1),f_XMY(C2),…,f_XMY(C n );C i ∈[MI_Z,MA_Z], , i=1,2,…,n-1}, where f_XMY(C i ) represents the second cutting plane set x-y=C i The plane of the second cutting plane is defined as the third cutting plane set Cut_Th, where Cut_Th = {f_MXY(D1), f_MXY(D2), ..., f_MXY(D n ),D i ∈[MI_Z,MA_Z], , i=1,2,…,n-1}, where f_MXY(D i ) represents the third cutting plane concentration y-x=C i plane; construct the union of Cut_Fs, Cut_Sc and Cut_Th sets as the total cutting set Cut_Sum.

6. The method for manufacturing a packaging container based on 3D printing according to claim 1, characterized in that: The method of strengthening the position where stress defects exist in the packaging container by weakening the risk is: if the risk mitigation edge does not pass through the space area of ​​the inner packaging, it is defined as a risk marking line, otherwise it is defined as a reference marking line; The value range of each structural weakening risk corresponding to the reference marker line is recorded as Z.RRSK; If the structural weakening risk of a risk marker line exceeds Z.RRSK, the risk marker line is defined as the first type of risk marker line; the vibration fatigue measurement interval VMI is preset, VMI∈(0,1] hours, the maximum bearing capacity of the printing material to be used in the buffer body printing model is P, and the maximum stress that the material can withstand before failure is S; Apply a vibration load in the interval (0, P) to the buffer body printing model every 0.1 milliseconds within the VMI interval, and record the real-time stress RS of the dynamic response of each point of the model. If the real-time stress RS of any point in the VMI interval is greater than or equal to P, then the point is recorded as the fatigue failure point of the buffer body printing model; if the risk mitigation edge contains a fatigue failure point, it is defined as the second-class risk marker line; The first and second risk marking lines are marked as high-risk marking lines, and the remaining risk marking lines are low-risk marking lines; the slices where the high-risk marking lines are located are reinforced: each slice that intersects with any high-risk marking line is identified from the Cura slicing software, and the uniform filling method is used to fill these slices, and the remaining slices continue to use the preset non-homogeneous filling method.

7. A manufacturing system for packaging containers based on 3D printing, characterized in that: The manufacturing and forming system of the packaging container based on 3D printing includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the manufacturing and forming method of the packaging container based on 3D printing described in any one of claims 1 to 6 are implemented. The manufacturing and forming system of the packaging container based on 3D printing runs on a desktop computer, a laptop computer, a PDA, and a computing device in a cloud data center.

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