A Support-Based Method for ID Marking of 3D Printed Components

Abstract

The present invention discloses a method for ID marking of 3D printed parts based on support, which is carried out according to the following steps: placing the 3D model, in the design software, placing the surface of the model with relatively low actual required precision downward as the overhanging surface; fine-tuning within a certain solid angle range, the software automatically traverses the height of the 3D model and selects the case of the lowest longitudinal height of the 3D model as the final placement method; adding label supports in the design software: adding other normal supports; printing out the parts with marks by a 3D printer. This method of the present invention uses the method of support pattern marking, which can not only quickly and correctly distinguish the printed parts, but also has the advantages that traditional marking does not have: it does not need to damage the original part structure; it is hidden in the gaps between normal supports and does not occupy additional forming space; it is formed at one time, reducing the consumption of printing materials and the printing time; because it is hidden in the gaps between normal supports, it does not increase the additional workload of turning and polishing.

Description

Technical field:

[0002] The present invention belongs to the technical field of denture processing, and in particular relates to a support-based 3D printing component ID marking method. Background technology:

[0004] In recent years, the application of additive manufacturing (also known as 3D printing) in various industries has developed rapidly, with the following characteristics: using the manufacturing method of accumulating materials layer by layer to save materials; no need to design additional molds, fast iteration speed; can manufacture three-dimensional structures that cannot be manufactured by traditional processing, such as porous structure models, etc. Therefore, it has huge market potential in the fields of personalized medicine, aerospace, jewelry processing, etc.

[0005] 3D printing service centers (such as 3D printing denture processing plants) receive a large amount of 3D model data from customers every day. From the perspective of production efficiency and cost, as much 3D model data as possible needs to be added to the forming area during one printing process. Therefore, there may be parts of multiple products or different parts of a single product in the forming area. If these parts are not marked, the staff will easily confuse products of similar shapes during the support removal process (wire cutting or sawing), and the staff will need to spend extra time to sort these unmarked products, and there is a possibility of errors and omissions during the sorting process. In order to solve the above problems, a marking method for special-shaped supports based on product ID information is proposed. Adding supports can play a role in supporting and reducing stress deformation in most 3D printing technology processes, and is an indispensable step. This support-based component marking method has the advantages of not destroying the original part structure, not occupying additional forming space, not increasing material loss, and not increasing printing time.

[0006] There are currently two mainstream traditional technical solutions:

[0007] 1. For example Figure 1 1. Print raised or recessed marks parallel to the surface of the part.

[0008] 2. For example Figure 1 2. A metal rod is manufactured along the normal direction of the part's solid surface, and a sheet-like marking plate is connected to the end.

[0009] The disadvantages of these two solutions or traditional technical solutions are:

[0010] 1. Both solutions significantly change the original part entity ( Figure 1 The structure of 3) affects the structure and dimensional accuracy of the printed product;

[0011] 2. Both solutions increase the amount of printing materials used and the printing time cost.

[0012] Disadvantages of Solution 1:

[0013] 1. Raised marks will increase the workload of gold plating and polishing for workers;

[0014] 2. Depressed marks change the structure of the original part and are only applicable to products that are not sensitive to local structure.

[0015] Disadvantages of Solution 2:

[0016] 1. The original surface may be damaged during the process of removing the metal rod;

[0017] 2. The position selection for adding the metal rod is restricted by the spatial conditions of the part (such as the surface curvature cannot be too high; there is enough surface space);

[0018] 3. It occupies additional forming space and often affects the utilization efficiency of the layout space.

[0019] The information disclosed in this background art section is only intended to enhance the understanding of the overall background of the present invention and should not be regarded as an admission or any form of implication that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Invention:

[0021] The purpose of the present invention is to provide a method for ID marking of 3D printed parts based on support, so as to overcome the defects in the above-mentioned prior art.

[0022] To achieve the above purpose, the present invention provides a method for ID marking of 3D printed parts based on support, which is carried out according to the following steps:

[0023] S1, placing the 3D model. In the design software, perform the following operations: Place the surface of the model with low actual precision requirements downward as the overhanging surface; Fine-tune within a certain solid angle range, and the software automatically traverses the height of the 3D model and selects the case of the lowest longitudinal height of the 3D model as the final placement method;

[0024] S2, adding label support in the design software:

[0025] S2.1, designing the shape of the sheet support, with a structure whose cross-section is a specific symbol / pattern when viewed from the bottom;

[0026] S2.2, calculating the bounding box for which label support needs to be added;

[0027] S2.3, adding position of the label: Obtain the label adding position according to the calculation;

[0028] S3, adding other normal supports

[0029] S4, printing out the parts with marks using a 3D printer.

[0030] A further limited technical solution of the present invention is as follows:

[0031] Preferably, in the above technical solution, step S2.3 is specifically as follows:

[0032] S2.3.1 Calculate the xy-plane projection of the model in this placement manner and the projection of the Gaussian curvature in this placement manner on the xy plane

[0033] S2.3.2 Determine whether the label bounding box can be typeset into this xy-plane projection by calculation

[0034] S2.3.3 If it cannot be typeset in: Reduce the length and width dimensions of the label to a times the original, and return to S2.3.1;

[0035] If the label bounding box can be typeset into the xy-plane projection, then go to step S2.3.4

[0036] S2.3.4 Calculate the scheme with the minimum area integral of the absolute value of the Gaussian curvature within the label bounding box among all typesetting possibilities.

[0037] Preferably, in the above technical solution, step S2.3 is specifically as follows:

[0038] S2.3.1 Calculate the xy-plane projection of the model in this placement manner and the projection of the Gaussian curvature in this placement manner on the xy plane;

[0039] S2.3.2 Calculate the xy-plane projection of the model in this placement manner, obtain the points with the farthest Euclidean distance from the projection contour, and obtain the farthest Euclidean distance r. Draw circles with these points as the centers and a circle with a radius of the Euclidean distance r is the typesetting area. Perform a union operation on these circles, and the obtained union result is the typesetting area;

[0040] S2.3.3 Determine whether 2r is greater than the diagonal length of the label. If 2r is less than the diagonal length of the label: Reduce the label size to a times the original. If 2r is greater than the diagonal length of the label: Keep the label size unchanged;

[0041] S2.3.4 Calculate the scheme with the minimum area integral of the absolute value of the Gaussian curvature within the label bounding box among all typesetting possibilities within the typesetting area.

[0042] Preferably, in the above technical solution, step S2 can also be replaced by this solution. Add normal columnar supports using design software, and the columnar supports present a dot matrix form; Add connecting parts between the normal columnar support dot matrices according to preset principles to form a label support with ID information.

[0043] Preferably, in the above technical solution, a support identification solution is further included: after printing is completed, a cutting tool such as wire cutting is used to separate the support from the forming base. The binoculars look directly at the ID support from the bottom of the part, and sorting is carried out according to the shape information of the support ID.

[0044] Preferably, in the above technical solution, a support removal and post-processing solution is further included: the removal of the support carrying the ID information is the same as that of the ordinary support: it can be removed with a similar tool such as a pair of sharp-nose pliers;

[0045] The turning and polishing of the residual part of the support carrying the ID information are the same as those of the ordinary support.

[0046] Preferably, in the above technical solution, the specific symbol / pattern is a number or a letter.

[0047] Preferably, in the above technical solution, in step S1, the solid angle range is within the solid angle range of a cone with a vertex angle of 30°.

[0048] Preferably, in the above technical solution, the design software is CAD design software, P3DS slicing software or other conventional design software in the industry.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The method of using support pattern marking in the present invention is realized, which can not only quickly and correctly distinguish printed parts, but also has advantages that traditional markings do not have:

[0051] 1. There is no need to damage the original part structure;

[0052] 2. It is hidden in the gap between normal supports and does not occupy additional forming space;

[0053] 3. It is formed in one step, reducing the loss of printing materials and the printing time;

[0054] 4. Since it is hidden in the gap between normal supports, it does not increase the workload of turning and polishing additionally. BRIEF DESCRIPTION OF THE DRAWINGS:

[0056] Figure 1 are schematic diagrams of two traditional markings;

[0057] Figure 2 is a schematic diagram of the first type of label support with ID information;

[0058] Figure 3 is a schematic diagram of the second type of label support with ID information.

[0059] In the figure: 1: Print raised marks or sunken marks closely parallel to the surface of the part. 2: Manufacture a metal rod along the normal direction of the part surface, with a flake-shaped tag attached to the end. 3: Ordinary support. 4: Printed solid. 5: The first type of tag support with ID information. 6: The second type of tag support with ID information attached to the normal support. Specific implementation method:

[0061] The following describes the specific implementation method of the present invention in detail, but it should be understood that the protection scope of the present invention is not limited by the specific implementation method.

[0062] Unless otherwise clearly stated, in the whole specification and claims, the term "comprising" or its variations such as "including" or "having" etc. will be understood to include the stated elements or components, and does not exclude other elements or other components.

[0063] Taking the first type of tag support with ID information as an example, the specific implementation steps are as follows:

[0064] 1. Automatically import the three-dimensional STL model of the dental crown into the company's P3DS slicing software, and place the occlusal surface of the dental crown with relatively low actual accuracy requirements downward (defining the upward direction as the positive direction of the z-axis), as the overhanging surface.

[0065] 2. Automatically traverse within the solid angle range of a cone with a vertex angle of 30° at a certain step size, and select the situation with the lowest height in the z-axis direction of the three-dimensional model as the final placement method.

[0066] 3. Automatically number all parts with ID information in the company's P3DS slicing software. The numbering rule is in the form of "processing factory" + "number". Different processing factories are distinguished by letters such as a, b, c, d, etc., and different parts in the same processing factory are distinguished by numbers such as 1, 2, 3, 4,..., 10, 11... etc. The form of letters and numbers refers to an 11-segment digital tube.

[0067] 4. Calculate the bounding box that needs to add the ID information tag support. In P3DS, for an n-bit tag (explanation: "12" is a tag with a length of 2, "abc" is a tag with a length of 3), the initial setting of the bounding box size of the tag is: width: 1.2 mm * n + 0.2 mm * (n - 1), height: 2.6 mm, where 1.2 mm is the width of one character, 0.2 mm is the spacing between adjacent characters, and 2.6 mm is the height of one character).

[0068] 5. P3DS automatically calculates the addition position of the ID tag:

[0069] Calculate the xy-plane projection of the model in this placement method, use the morphological erosion algorithm to obtain the points with the farthest Euclidean distance from the projection contour, and obtain the farthest Euclidean distance r. The circles with these points as the centers and the Euclidean distance r as the radius are the typesetting areas. Perform a union operation on these circles, and the union result obtained is the typesetting area.

[0070] 5-2 Determine whether 2r is greater than the diagonal length of the label.

[0071] a) If 2r is less than the diagonal length of the label: Reduce the label size to a times the original (a = diagonal length of the label / (2r)).

[0072] b) If 2r is greater than the diagonal length of the label: Keep the label size unchanged.

[0073] 5-3 In the typesetting area, calculate the solution with the smallest area integral of the absolute value of the Gaussian curvature within the label bounding box among all typesetting possibilities.

[0074] 6. Add other normal supports.

[0075] 7. Use the P3DS slicing software to slice the STL file and output the format that can be read by the company's 3D printing device TR150.

[0076] 8. TR150 reads the sliced data and prints.

[0077] 9. Heat-treat the printed product to eliminate stress.

[0078] 10. Cut the printed product using a wire cutting machine, remove the product with supports from the forming base, sort the crowns of each processing factory according to the support ID with information, put each crown into a small plastic bag with a label, and put all the small plastic bags of the same processing factory into the same large plastic bag.

[0079] 11. Send all the printed products back to each processing factory, and they will complete the post-processing operations such as support removal and turning and gold polishing by themselves.

[0080] The foregoing description of the specific exemplary embodiments of the present invention is for the purpose of illustration and exemplification. These descriptions are not intended to limit the present invention to the precise forms disclosed, and obviously, many changes and variations can be made according to the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical applications, so that those skilled in the art can implement and utilize various different exemplary embodiments of the present invention as well as various different selections and changes. The scope of the present invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for ID marking of 3D printed parts based on supports, which is carried out according to the following steps: S1. Placement of the 3D model. In the design software, perform the following operations: Place the surface of the model with relatively low actual precision requirements downward as the overhanging surface; Fine-tune within a certain solid angle range, and the software automatically traverses the height of the 3D model and selects the case of the lowest longitudinal height of the 3D model as the final placement method. S2. Add label supports in the design software: S2.

1. Design the shape of the sheet support, whose front view section from the bottom is a structure with a specific symbol / pattern. S2.

2. Calculate the bounding box for which label supports need to be added. S2.

3. Position for adding the label: Obtain the label adding position according to the calculation. S3. Add other normal supports. S4. Use a 3D printer to print out the parts with the markings.

2. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: Step S2.3 is specifically as follows: S2.3.1 Calculate the xy-plane projection of the model in this placement method and the projection of the Gaussian curvature of the model in this placement method on the xy plane. S2.3.2 Determine whether the label bounding box can be typeset into this xy-plane projection through calculation. S2.3.3 If it cannot be typeset into: Reduce the length and width dimensions of the label to a times the original and go back to S2.3.

1. If the label bounding box can be typeset into the xy-plane projection, then go to step S2.3.

4. S2.3.4 Calculate the scheme with the minimum area integral of the absolute value of the Gaussian curvature within the label bounding box among all typesetting possibilities.

3. The method for ID marking of 3D printed parts based on support according to claim 1, wherein: Step S2.3 is specifically as follows: S2.3.1 Calculate the xy-plane projection of the model in this placement method and the projection of the Gaussian curvature of the model in this placement method on the xy plane. S2.3.2 Calculate the xy-plane projection of the model in this placement method, obtain the points with the farthest Euclidean distance from the projection contour, and obtain the farthest Euclidean distance r. Draw circles with these points as the centers and the Euclidean distance r as the radius. The union of these circles is the typesetting area. S2.3.3 Determine whether 2r is greater than the diagonal length of the label. If 2r is less than the diagonal length of the label: Reduce the label size to a times the original. If 2r is greater than the diagonal length of the label: Keep the label size unchanged. S2.3.4 Calculate the scheme with the minimum area integral of the absolute value of the Gaussian curvature within the label bounding box among all typesetting possibilities within the typesetting area.

4. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: Step S2 can also be replaced by the following scheme: Add normal columnar supports using the design software, and the columnar supports present a dot matrix form. Add connection parts between the normal columnar support dot matrices according to the preset principle to form label supports with ID information.

5. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: It also includes a support identification scheme: After printing is completed, use cutting tools such as wire cutting to separate the supports from the forming base, view the ID supports from the bottom of the part with binoculars, and perform sorting according to the support ID shape information.

6. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: It also includes a support removal and post-processing scheme: The removal of the supports carrying ID information is the same as that of ordinary supports: Just remove them with tools such as needle-nose pliers. The turning and polishing of the remaining parts of the supports carrying ID information are the same as those of ordinary supports.

7. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: The specific symbol / pattern is a number or a letter.

8. The method for ID marking of a support-based 3D printed component according to claim 1, characterized in that: In step S1, the solid angle range is within the solid angle range of a cone with a vertex angle of 30°.

9. The method for ID marking of 3D printed parts based on support according to claim 1, characterized in that: The design software is CAD design software, P3DS slicing software, or other conventional design software in the industry.

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