A low-cost manufacturing method for a color model with a transparent shell based on 3D printing
By combining melt deposition molding and surface exposure 3D printing technology, transparent shells are generated and silicone is poured into it, and color printing is combined with a color mixing FDM printer, the problem of high costs in the existing technology is solved, and the manufacturing of low-cost transparent color models is realized, and new 3D printing application ideas.
Patent Information
- Application Number
- CN202211313380.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-10-26
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2042-10-26
AI Technical Summary
Existing 3D printing technology is difficult to manufacture transparent and colorful models at low cost, especially due to the high cost of materials and equipment, which limits the application of ordinary people.
Using 3D printing technology combined with melt deposition molding (FDM) and surface exposure, the assembly of the transparent shell and color interior is achieved by generating a transparent shell model and filling silicone with a color mixing FDM printer.
It realizes the low-cost manufacturing of transparent shell color models, reduces equipment and material costs, while improving printing efficiency and effect, and provides new 3D printing application ideas.
Smart Images
Figure CN115648618B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to intelligent 3D printing technology, specifically to fused deposition modeling (FDM) and surface exposure 3D printing technology, and includes three-dimensional model processing technology, which processes the model and uses different 3D printing technologies to manufacture different parts of the model, thereby efficiently realizing low-cost manufacturing of color models with transparent shells based on 3D printing. Background Art
[0002] 3D printers were invented by American scientists in the mid-1980s. 3D printers are devices that use 3D printing technology to produce real three-dimensional objects. The basic principle is to use special consumables (glue, resin or powder, etc.) according to the three-dimensional model pre-designed by the computer, and then bond each layer of powder into shape through the deposition of adhesives, and finally print out a 3D entity.
[0003] Rapid prototyping technology is widely used in model making in the product development stage due to its fast processing speed and low cost. 3D printing is a type of rapid prototyping technology. It first converts objects into 3D data, and then uses powdered metal or plastic and other bondable materials to print layer by layer. Mold manufacturing and industrial design are used to build models, and are now developing into product manufacturing, forming "direct digital manufacturing". At present, many different rapid prototyping processes have been formed, such as stereolithography (SLA), laminated object manufacturing (LOM), fused deposition modeling (FDM), selective laser sintering (SLS), three-dimensional printing (3DP), etc. There are three main types of photolithography technology: surface exposure, line scanning and point prototyping technology.
[0004] Due to the limitation of materials and technology, only a few 3D printers using photo-curing technology can print transparent objects. In this regard, the company that has made relatively advanced progress is Sena 3D, which mainly uses line scanning (Polyjet) technology for model manufacturing. They can print multiple materials at the same time, and can print full-color and transparent objects. However, the cost of this technology is extremely expensive. Both 3D printers and printing consumables are not affordable for ordinary people. Therefore, it is particularly important to find a model manufacturing method that can ensure that the printed model can be colorful and can print transparent objects while ensuring low cost. Summary of the invention
[0005] The embodiment of the present invention provides a low-cost manufacturing method of a color model with a transparent shell based on 3D printing, which is aimed at a three-dimensional model that needs to make the shell transparent and view the internal information of the model.
[0006] To solve the above technical problems, the embodiments of the present invention adopt the following technical solutions:
[0007] A low-cost manufacturing method for a color model with a transparent shell based on 3D printing comprises the following steps:
[0008] Step 100: Divide the model to be manufactured into a part to be printed in color and a part to be made transparent.
[0009] Step 200, based on the information of the two parts of the model to be printed, generate a rectangular parallelepiped model that is larger than the model as a whole, which will be used to pour transparent colloid later and is defined as a shell model;
[0010] Step 300: Divide the shell model into multiple parts according to the characteristics of the model to be manufactured, and print them using a surface exposure 3D printer with a faster printing speed;
[0011] Step 400: Use a mixed color FDM 3D printer to perform integrated color printing on the part that needs to be printed in color;
[0012] Step 500: Assemble the colored part printed by FDM technology with the shell model, and inject silicone. After the silicone is cured, remove the shell model to obtain the final desired model.
[0013] Wherein, according to the two parts of model information to be printed, a rectangular parallelepiped model that is larger than the model as a whole is generated, which will be used for pouring transparent colloid later and is defined as the shell model, step 200 includes:
[0014] Measure the bounding box of the model to be manufactured and generate a rectangular model larger than the bounding box;
[0015] The model to be manufactured is placed in this rectangular model to obtain a difference set, and a hollow shell model with an internal contour of the model to be printed is obtained.
[0016] The step 300 of dividing the shell model into multiple parts according to the characteristics of the model to be manufactured and printing the shell model using a surface exposure 3D printer with a faster printing speed includes:
[0017] Traverse the model to be manufactured, find the position with the largest cross-sectional area of the model, and use it as the dividing surface of the shell model to divide the shell model into two parts;
[0018] At the interface of the two parts of the shell model, one part is extended outward from the split surface, and the other part is removed from the corresponding part, so as to obtain an embeddable structure, which can play the role of fixing and preventing leakage after the two parts are assembled;
[0019] The shell model is 3D printed using surface exposure technology.
[0020] The step 400 of using a mixed color FDM 3D printer to perform integrated color printing on the part that needs to be printed in color includes:
[0021] The user sets the color to be printed and sets the color mixing ratio according to the material subtractive three-primary color mixing algorithm;
[0022] The FDM 3D printer with four-way filament input and dual print head output is constructed by using three-input and one-output print heads (three filament input ports and one material extrusion port) and one-input and one-output (one filament input port and one material extrusion port). The three-input and one-output print heads are used to print mixed-color objects, and the one-input and one-output print heads are used to print model support parts. Then, the G-code is further planned according to the relative positions of the two print heads.
[0023] A low-cost manufacturing method of a color model with a transparent shell based on 3D printing according to an embodiment of the present invention has the following advantages:
[0024] 1) Combining different 3D printing technologies together provides new ideas for model manufacturing and provides reference for future 3D printing applications;
[0025] 2) Keep the cost low while ensuring that the manufactured items can be printed in color and transparent colors;
[0026] 3) The proposed four-input dual-output FDM printing structure can print easily removable support materials while achieving target color printing by mixing three primary color materials. Therefore, the present invention has certain application value and significance. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 This is the liver example model
[0028] Figure 2 This is the schematic diagram of the FDM3D printer and the schematic diagram of the three-input and one-output print head structure
[0029] Figure 3 This is the flowchart of the method
[0030] Figure 4 This is a schematic diagram of the printing direction after rotation
[0031] Figure 5 This is the initial segmentation diagram
[0032] Figure 6 This is a schematic diagram of the shell model after the buckle is generated.
[0033] Figure 7 This is a diagram of assembling the colored part with the outer shell.
[0034] Figure 8 This is the final printed product diagram DETAILED DESCRIPTION
[0035] The embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily.
[0036] The invention provides a low-cost manufacturing method of a color model with a transparent shell based on 3D printing, which can print a model requiring a transparent shell.
[0037] Now let's take a liver model as an example, which includes an organ model and a blood vessel model inside it. Figure 1 As shown. Currently, the liver models used in many applications and teaching are still a whole piece of reddish brown. If you want to see the inside, you need to make a cross-sectional model. In order to solve this problem, we can see the blood vessels inside the liver more intuitively, so the appearance of the finished organ is required to be transparent. In this regard, the existing technology mainly uses Polyjet technology to print this transparent model with photosensitive resin as the material. The price of this material and printer is very expensive. In order to solve this problem, the present invention intends to use FDM3D printing technology to print the color part, but the current FDM3D printing technology cannot print transparent objects, and the speed is relatively slow when printing large objects. Therefore, it is thought of quickly printing a shell model through surface exposure technology, and printing a model with a transparent appearance is achieved by pouring transparent silicone.
[0038] The FDM 3D printer used in this scheme has a four-input, side-by-side double-head structure, such as Figure 2 The overall "three in and one out" and "one in and one out" form a dual print head structure, which can realize color printing and water-soluble support printing respectively.
[0039] The "three-in-one-out" print head is a color mixing extrusion unit, which consists of three feeding ends and a mixing nozzle. The three primary color consumables are fed into the mixing nozzle in proportion, and are mixed and extruded to form colored materials after being fully heated in the mixing chamber. The mixing ratio of the three primary colors is automatically calculated by the CMY color mixing algorithm, and precise extrusion is achieved through the color mixing control unit. The color mixing control unit is responsible for converting the mixing ratio of the three primary color consumables into the corresponding extrusion length, which is finally expressed in the G-code code to achieve mixed extrusion. In view of the problem of transition bands in the color switching process during color mixing, a precise color control method based on a switching tower is adopted to ensure the color quality of color printing. For the support parts in the printing process, a "one-in-one-out" print head is used for printing separately, and water-soluble transparent materials are used as consumables. After printing, it is placed in alcohol and soaked for a period of time. The water-soluble support part gradually dissolves and only the main part of the model is retained, which maximizes the retention of model details and reduces the damage to the model when the support is removed.
[0040] Figure 3 The present invention is a flowchart of a low-cost manufacturing method of a color model with a transparent shell based on 3D printing according to an embodiment of the present invention.
[0041] The embodiment of the present invention provides a low-cost manufacturing method of a color model with a transparent shell based on 3D printing, comprising:
[0042] Step 100: Divide the model to be manufactured into a part to be printed in color and a part to be made transparent.
[0043] Step 200, based on the information of the two parts of the model to be printed, generate a rectangular parallelepiped model that is larger than the model as a whole, which will be used to pour transparent colloid later and is defined as a shell model;
[0044] Step 300: Divide the shell model into multiple parts according to the characteristics of the model to be manufactured, and print them using a surface exposure 3D printer with a faster printing speed;
[0045] Step 400: Use a mixed color FDM 3D printer to perform integrated color printing on the part that needs to be printed in color;
[0046] Step 500: Assemble the colored part printed by FDM technology with the shell model, and inject silicone. After the silicone is cured, remove the shell model to obtain the final desired model.
[0047] The step 200 includes the following sub-steps:
[0048] Sub-step 210: Rotate the whole liver model so that a portion of the external blood vessels are turned downward, such as Figure 4 As shown in the box, the printing direction is now defined as from bottom to top.
[0049] Sub-step 220 , measuring the bounding box of the model at this time, and increasing the length, width and height of the bounding box by 20 mm respectively, to generate a rectangular parallelepiped model.
[0050] Sub-step 230: Put the liver model into the cuboid model to obtain a difference set, thereby obtaining a hollow shell model whose internal contour is the liver model.
[0051] The step 300 includes the following sub-steps:
[0052] Sub-step 310, traverse the liver model in the printing direction, find the position with the largest cross-sectional area as the dividing surface, and divide the shell model into upper and lower parts.
[0053] In order to ensure that the blood vessel model can be inserted into the shell model and fixed, it is necessary to ensure that the gap in the shell is completely divided into the lower half of the model. Therefore, it is necessary to find the part with the largest cross-sectional area of the model above the bayonet as the segmentation surface. The segmentation result is as follows: Figure 5 As shown, a 10 mm diameter hole is opened at the thinnest part of the upper half of the model for pouring.
[0054] Sub-step 320, obtain the image of the internal hollow part of the segmented cross section, dilate the image, expand the edge outward by 5 mm, use this expanded image to stack in the vertical direction to generate a 10 mm thick body model, put this model into the lower part of the shell model to find the "intersection" to obtain the buckle model, find the difference set of the buckle model and the lower half of the shell model, and find the union set of the buckle model and the upper half of the shell model, thereby obtaining a shell model that can be fixed to each other, such as Figure 6 shown.
[0055] Sub-step 330: Print the upper and lower shell models separately using a surface exposure 3D printer.
[0056] The step 400 includes the following sub-steps:
[0057] Sub-step 410, the user sets the color of the blood vessel part, calculates the mixing ratio of the three primary colors through the CMY subtractive color mixing algorithm, and adjusts the input ratio of the three extruders in the three-input and one-output print head according to the obtained ratio to achieve the color mixing effect. Most FDM3D printers are controlled by a motherboard developed based on the Ma Lin firmware. The control principle is essentially to control the movement of the motor of the direction axis and the motor of the extruder. Therefore, we define a control function in the Ma Lin firmware. While printing, the three extruder motors of the three-input and one-output extruder head can extrude at the same time in the corresponding ratio. After the setting is completed, a G-code file that can be recognized by the 3D printer can be generated in the slicing software. This blood vessel model is a dark orange mixed with magenta and yellow consumables in a ratio of 8:2.
[0058] Optionally, the three primary colors can be mixed together in any proportion to achieve the color set by the user. If there are multiple models, different colors can be set for each model and printed in an integrated manner through a mixed-color printer. We store the required mixing ratio of each color in a virtual extruder defined by ourselves, which can be set up to 6 times. When printing, the corresponding ratio of the extruder will be automatically called for printing. There will be a color buffer when switching colors during the printing process, that is, the color difference will be caused by untimely color switching. At this time, a switching tower is introduced. After one color prints a layer, switch to the next color to print a layer of the switching tower. At this time, the color is completely switched to the next target color.
[0059] Sub-step 420: Since the commonly used slicing software can only be adapted to common 3D printers, this type of 3D printer with color mixing function usually has only one extruder head, so we need further path planning. We put the extrusion positions of the three-input and one-out print heads and the one-input and one-out print heads on the same horizontal line, and then measure the relative coordinate distance between the two print heads on the xy axis. We read the G-code file that the 3D printer can recognize that was generated before. The content of the G-code file is a line of coordinate information to command the printer to move. At this time, we find the path coordinate information of the support structure of the model, add the measured relative coordinate distance of the two print heads, and save it as the final printable file. At this time, during the printing process, the printer will automatically use the 1-input and 1-out print head to print the support part.
[0060] Sub-step 430: remove the printed model, soak it in alcohol, and wait for the water-soluble support part to completely dissolve.
[0061] The step 500 includes the following sub-steps:
[0062] Sub-step 510: assemble the blood vessel model printed in step 400 and the shell model printed in step 330, as shown in FIG. Figure 7 shown.
[0063] Sub-step 520, use transparent liquid silicone to inject from the opening of the shell model through a funnel, wait for the silicone to completely solidify, remove the shell model, and obtain the final desired transparent color model.
[0064] Optionally, the transparent part can be made of any material that can be cured from liquid to solid. In this solution, SYLGARD 184 silicone elastomer from Dow Corning is used. It is poured into the shell model and cured for 30 minutes at 100 degrees Celsius. After that, the shell is removed to obtain a model with a transparent effect, such as Figure 8 shown.
[0065] A medical model printing method combining fused deposition modeling and surface exposure 3D printing technology according to an embodiment of the present invention has the following advantages:
[0066] 1) Combining different 3D printing technologies together provides new ideas for model manufacturing and provides reference for future 3D printing applications;
[0067] 2) Keep the cost low while ensuring that the manufactured items can be printed in color and transparent colors;
[0068] 3) The proposed four-input dual-output FDM printing structure can print easily removable support materials while achieving target color printing by mixing three primary color materials. Therefore, the present invention has certain application value and significance.
Claims
1. A low-cost manufacturing method for a color model with a transparent shell based on 3D printing, characterized in that: The following steps are involved: Step 100, dividing the model to be manufactured into a part to be printed in color and a part to be made transparent; Step 200, based on the information of the two parts of the model to be printed, generate a rectangular parallelepiped model that is larger than the model as a whole, which will be used to pour transparent colloid later and is defined as a shell model; Step 300: Divide the shell model into multiple parts according to the characteristics of the model to be manufactured, and print them using a surface exposure 3D printer with a faster printing speed; Step 300 includes: Traverse the model to be printed in the entire printing direction, find the position with the largest cross-sectional area as the model splitting surface, and split it into two parts; An embedded card slot is generated at the dividing surface to fix and prevent leakage, and a hole is opened at the thinnest position at the top for perfusion; Print the two-part shell model using a DLP3D printer; Step 400: Use a mixed color FDM 3D printer to perform integrated color printing on the part that needs to be printed in color; Step 500: Assemble the colored part printed by FDM technology with the shell model, and inject silicone. After the silicone is cured, remove the shell model to obtain the final desired model.
2. The method according to claim 1, characterized in that Step 100 includes: Take a model that needs to be manufactured, find the part that needs to be printed in color, and separate it into several independent 3D models according to different color requirements.
3. The method according to claim 1, characterized in that Step 200 includes: Measure the outer bounding box of the model to be manufactured and generate a rectangular model larger than the bounding box; The entire model to be manufactured is placed into the rectangular model and the difference is calculated to obtain a hollow shell model whose internal contour is the model to be printed.
4. The method according to claim 1, characterized in that: Step 400 includes: The user sets the color to be printed, and sets the color mixing ratio according to the color mixing algorithm of the three primary colors of the material subtraction, and changes the G-code file that the printer can recognize to control the printer to extrude the material in the corresponding ratio; Printing is performed using a dual print head structure, including a three-input-one-out print head, i.e., three consumables input ports and one material extrusion port, and a one-input-one-out print head, i.e., one consumables input port and one material extrusion port, to construct an FDM 3D printer with a four-way consumables input and dual print head output configuration. The three-input-one-out print head is used to print mixed-color objects, and the one-input-one-out print head is used to print model support parts; then, the G-code is further path-planned according to the relative positions of the two print heads; Use an FDM 3D printer to print the colored part. After removing the printed product, soak it in water or alcohol and remove the support part.