An integrated printing method, system and storage medium

Abstract

The application provides a kind of integrally formed printing method and printing system, including printing model processing, according to slice path, the layer height, printing speed and extrusion speed of each path point are calculated, and printing equipment is carried out printing by program upload.The printing method of the application is sliced at a certain inclination angle, the outer contour surface of single layer is smaller, the shrinkage deformation is reduced, and the shrinkage problem of large length-to-diameter ratio component under horizontal printing mode is greatly reduced;Then, through the change of single layer printing layer height, the continuous change of each layer printing plane is realized, the support amount can be greatly reduced, and the stress performance is changed.The application adopts flexible, large-scale inclined variable-angle 3D printing method, solves the problem that the forming size range applied by the existing large-scale component 3D printer is limited and the printing flexibility is not high, and it is difficult to print large length-to-diameter ratio parts.

Description

Technical Field

[0001] This invention relates to the field of large-scale FDM 3D printing technology. Background Technology

[0002] 3D printing, a type of rapid prototyping technology, is a technique that constructs objects layer by layer based on digital model files. Traditional large-scale 3D printing typically uses gantry printers, often referred to as Cartesian coordinate system printers. In the fields of architecture, engineering, and construction (AEC), due to the large dimensions of components, 3D printing technology has significant requirements regarding structural stability and thermal shrinkage. Therefore, traditional printing equipment cannot meet the requirements for designing complex models on a large scale, presenting at least the following technical challenges:

[0003] 1. When printing large components, existing 3D printing equipment needs to deal with large shrinkage deformation, and may even need to build a constant temperature room to reduce warping during the printing process.

[0004] 2. For components with a large aspect ratio, such as a 6m long and 1m wide and high component, it is theoretically possible to use a vertical printing method, but this would significantly increase the cost of the equipment's z-axis.

[0005] 3. Traditional 3D printing is mostly horizontal layering, which requires support to achieve certain specific shapes. Summary of the Invention

[0006] The purpose of this invention is to partially or completely solve the above-mentioned shortcomings in the prior art and provide a 3D printing method for integral molding of large components, thereby improving printing flexibility and molding size range.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] In a first aspect, embodiments of the present invention provide an integral molding printing method, comprising the following steps:

[0009] 1) Printed model processing: Based on the overall trend of the model, select the standard placement posture, then analyze the surface curvature characteristics of the model, slice it with a constant angle and layer height, and confirm whether the slicing result meets the overhang limit; if it does not meet the overhang limit, the model needs to be rotated along one or more axes and sliced ​​again to verify the result;

[0010] 2) Based on the placement and slicing results determined in step 1), decide whether to produce the corresponding printing mold; if no mold is needed, use a conventional printing platform.

[0011] 3) Model printing angle limitation: If printing from right to left, use the horizontal direction as the reference and print on a plane between the horizontal and / or 90° counterclockwise rotation.

[0012] 4) Based on the slicing path, calculate the layer height, printing speed, and extrusion speed at each path point, and upload the data to the printing device for printing.

[0013] Step 1) The standard placement posture refers to: setting the printing deposition direction as +x (horizontal guide rail direction), vertical upward as +z, selecting the origin as the centroid of the model, establishing a Cartesian coordinate system, and placing the model so that the direction of its long dimension is parallel to the x-axis.

[0014] Furthermore, the slicing angle in step 1) is preferably 30-60°, and the standard layer height is preferably half the nozzle diameter.

[0015] If the standard model orientation in step 1) does not meet the overhang restrictions, the results need to be verified by slicing again. This involves rotating the model around the x-axis and y-axis respectively, and then slicing again for verification; the x-axis rotation angle should be within ±180°, and the y-axis rotation angle within ±30°. If the results still do not meet printing requirements, the model needs to be further segmented using UV lines to generate printing surfaces. The standard layer height should be half the nozzle diameter, while the height of each printing layer should be within the layer height variation range. Finally, the y-axis angle of the model should be adjusted so that all surfaces are within the model printing angle limits.

[0016] Furthermore, if the printing angle, layer height, or overhang distance of some parts of the segmentation result in step 1) exceeds the limit, the layer height is finely adjusted between several consecutive cut surfaces to meet the limit requirement.

[0017] Furthermore, the formula for calculating the cantilever angle of the model surface mentioned in step 1) is as follows:

[0018] α = 90° - arctan (h / P*D)

[0019] h = floor height (mm), D = line width (mm); P is the overhang ratio, which should be adjusted according to the situation, preferably 30%-40%.

[0020] The height of a single printed layer is preferably gradually varied between 1-80% of the nozzle diameter to achieve variations in the angle between multiple printed layers. The formula for calculating the angle that can vary for each layer is: β=arctan((a+b) / L), where a is the minimum height of the layer, b is the maximum height of the layer, and L is the distance between the maximum and minimum height points.

[0021] Based on the printing process, determine the line width and nozzle size to be used. The formula for matching the extrusion speed, printing speed, and layer height is as follows:

[0022] Extrusion speed r = (h*D*ρ*v) / k

[0023] h is the floor height (mm), D is the line width (mm), and ρ is the material density (g / cm³). 3 v is the printing speed in m / s, and k is the weight of material extruded per screw revolution in g.

[0024] Furthermore, in step 2), if the slicing angle result from step 1) shows that the protrusion angle of the model surface exceeds the maximum tilt angle, affecting the printing quality, then mold support is used. Small-area mold support parts are pre-printed on the printing platform; large-area or complex mold support requires additional mold fabrication. The fabricated mold is then 3D scanned and reconstructed, imported into the model, and repaired after comparing errors.

[0025] Secondly, embodiments of the present invention provide an integral molding printing system, comprising:

[0026] The printing model processing unit 100 is used to: select a standard placement posture according to the overall trend of the model, then analyze the curvature characteristics of the model surface, slice the model at a constant angle and layer height, and confirm whether the slicing result meets the overhang limit; if the overhang limit is not met, the model needs to be rotated along one or more axes and sliced ​​again to verify the result.

[0027] Select mold unit 200 to: select whether to produce the corresponding printing mold based on the placement posture and slicing results determined by printing model processing unit 100; if no mold is needed, use a conventional printing platform.

[0028] The printing angle confirmation unit 300 is used for: printing from right to left, with the horizontal direction as the reference, and printing on a plane between the horizontal and / or 90° counterclockwise rotation.

[0029] Variable angle 3D printing equipment 400, used for printing;

[0030] The print parameter calculation unit 500 is used to: calculate the layer height, printing speed and extrusion speed of each path point according to the slicing path, and upload them to the printing device 500.

[0031] Furthermore, the printing model processing unit 100 includes a first subunit 101, used to calculate the protrusion angle of the model surface, and the calculation formula is as follows:

[0032] α = 90° - arctan (h / P*D)

[0033] h = floor height, D = line width, P is the overhang ratio, which should be adjusted according to the situation, preferably 30%-40%.

[0034] The height of a single printed layer is preferably gradually varied between 1-80% of the nozzle diameter to achieve variations in the angle between multiple printed layers. The formula for calculating the angle that can vary for each layer is: β=arctan((a+b) / L), where a is the minimum height of the layer, b is the maximum height of the layer, and L is the distance between the maximum and minimum height points.

[0035] The standard placement posture described in the printing model processing unit 100 refers to: setting the printing deposition direction as +x (horizontal guide rail direction), vertical upward as +z, selecting the origin as the centroid of the model, establishing a Cartesian coordinate system, and placing the model so that its long dimension direction is parallel to the x-axis.

[0036] Furthermore, the slicing angle of the printing model processing unit 100 is preferably 30-60°, and the standard layer height is preferably half the nozzle diameter.

[0037] When the standard orientation of the model fails to meet the overhang limit, the printing model processing unit 100 needs to re-slice and verify the results. Further, it includes a second sub-unit 102, used to: rotate the model around the x-axis and y-axis respectively, and re-slice and verify; the x-axis rotation angle is within ±180°, and the y-axis rotation angle is within ±30°. If the results still do not meet the printing requirements, it may further include a third sub-unit 103, used to: perform UV line segmentation on the model to generate printing cut surfaces, with a standard layer height of half the nozzle diameter, while the height of each printing layer is within the layer height variation range; finally, it adjusts the y-axis angle of the model so that all cut surfaces are within the model printing angle limit range.

[0038] Furthermore, if some printing angles, layer heights, or overhang distances in the segmentation results of the printing model processing unit 100 exceed the limits, the layer heights are fine-tuned between several consecutive cut surfaces to meet the limit requirements.

[0039] One possible approach for selecting mold unit 200 is as follows: if the slicing angle results from the printing model processing unit 100 show that the cantilever angle of the model surface exceeds the maximum tilt angle, then mold support is employed. Furthermore, small-area mold support components can be pre-printed on the printing platform, while large-area or complex mold supports require additional mold fabrication. The fabricated mold is then 3D scanned and reconstructed, imported into the model, and repaired after error comparison.

[0040] Furthermore, the printing parameter calculation unit 500 includes an algorithm unit 501, which is used to calculate the printing speed. The formula for the combination of extrusion speed, printing speed and layer height is: extrusion speed r = (h*D*ρ*v) / k, where h is the layer height, D is the line width, ρ is the material density, and k is the weight of material extruded per screw revolution.

[0041] One possible solution is the variable angle 3D printing device 400.

[0042] The device includes a guide rail 401, a robot 402 with four or more axes, an extruder 403, a nozzle 404, a feeder 405, a printing platform 406, and a fan 407. The robot 402 is mounted on the guide rail 401 and moves freely. The extruder 403 is mounted on the end shaft of the robot 402. The nozzle 404 is connected to the end of the extruder 403, and the axis of the nozzle 404 forms an angle of 20-70° with the screw axis of the extruder 403. The feed pipe of the feeder 405 is connected to the barrel of the extruder 403. The fan 407 is mounted on the end wall of the extruder 403 and is used to cool the extruded material. The printing platform 406 is located below the extruder 403 and is used to support the printed parts and / or molds.

[0043] Thirdly, embodiments of the present invention provide an apparatus or terminal for integral molding printing, including one or more processors and a storage device; the storage device is used to store one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the integral molding printing method as described in any of the first aspects above.

[0044] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements an integral molding printing method as described in any of the first aspects above.

[0045] The beneficial effects of this invention are:

[0046] The printing method of the present invention slices the material at a certain tilt angle, which reduces the outer contour of a single layer and the amount of shrinkage deformation, thus greatly reducing the shrinkage problem of components with large length-to-slenderness ratio under horizontal printing. Then, by changing the height of a single layer, the printing plane of each layer can be continuously changed, which can greatly reduce the amount of support and change the stress performance.

[0047] The printing system of the present invention can achieve three-axis spatial movement by using a robot actuator with at least four axes to load the extruder. The angle of the extrusion nozzle can be adjusted, which also increases the flexibility of printing and allows for the printing of more complex shapes.

[0048] This invention employs a flexible, large-scale, tiltable, variable-angle 3D printing method, which solves the problems of limited molding size range, low printing flexibility, and difficulty in printing parts with large length-to-width ratios in existing large-scale component 3D printers.

[0049] The following describes specific embodiments of the present invention with reference to the accompanying drawings: Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the printed part protruding, and A is an enlarged view of the printed line width section.

[0051] Figure 2 This is a schematic diagram of the printed part being sliced, with B being the slicing plane.

[0052] Figure 3 Example diagram for calculating slice angle.

[0053] Figure 4 For the illustration of the cantilever angle analysis, C shows that the cantilever angle is greater than 63°.

[0054] Figure 5 A diagram showing how to set the slice angle.

[0055] Figure 6 A schematic diagram for supporting the mold.

[0056] Figure 7 This is a schematic diagram of a variable angle 3D printing device 400 provided in an embodiment of the present invention.

[0057] Figure 8 This is a schematic diagram of one of the connection relationships between the extruder and the nozzle of the variable angle 3D printing equipment 400 provided in an embodiment of the present invention, where they are set at an angle.

[0058] Figure 9 A flowchart of an integral molding printing method provided in an embodiment of the present invention.

[0059] Figure 10 This is a schematic diagram of an integrated molding printing system provided in an embodiment of the present invention.

[0060] Figure 11 These are experimental photos of the integral molding printing method and system of the present invention.

[0061] Figure label:

[0062] 100 Printing Model Processing Unit, 101 First Sub-unit, 102 Second Sub-unit

[0063] 103 Third Subunit

[0064] 200 Selectable Mold Unit

[0065] 300 Printing Angle Confirmation Unit

[0066] 400. Variable Angle 3D Printing Equipment; 401. Guide Rail; 402. Robot; 403. Extruder

[0067] 404 Nozzle, 405 Feeder, 406 Printing Platform, 407 Fan, 408 External Shaft

[0068] 409 Dryer, 410 Suction Feeder

[0069] Unit 500: Calculate Printing Parameters; Unit 501: Algorithm Unit

[0070] 600 printouts

[0071] 700 support Detailed Implementation

[0072] The specific embodiments described herein are merely illustrative of the technical solutions of this patent and are not intended to limit the scope of the disclosed technical solutions. It should also be noted that, for ease of description, the accompanying drawings show only the parts relevant to the technical solutions of this disclosure, and not the entire structure.

[0073] Before discussing the exemplary embodiments in more detail, it should be mentioned that the structure of the device components and / or modules mentioned in the embodiments, unless otherwise described in detail, is something that can be understood by those skilled in the art based on existing public technologies or is a commercially available product.

[0074] See Figure 9 , Figure 1-6 The integral molding printing method provided in this embodiment of the invention includes the following steps:

[0075] 1) Printing model processing:

[0076] 1.1 Analyze the overall trend of the model, set the printing deposition direction as +x (guide rail direction), vertical upward as +z, select the origin as the centroid of the model, establish a Cartesian coordinate system, and place the model so that the direction of its long dimension is parallel to the x-axis. At this time, the model is considered to be in a standard placement state.

[0077] 1.2 After the model is placed in the standard position, analyze the surface curvature characteristics of the model, and slice it with a constant angle and standard layer height. The angle is generally 30-60°, and the standard layer height is preferably half the nozzle diameter. Confirm whether the slicing result meets the overhang limit. If it does not meet the limit, the model needs to be rotated with the x-axis and y-axis as the rotation axis respectively, and the results are verified by slicing again. The rotation angle along the x-axis is within ±180°, and the rotation angle along the y-axis is within ±30°.

[0078] 1.3 If the result still does not meet the printing requirements, the model needs to be segmented by UV lines to generate printing surfaces. The standard layer height is generally half the nozzle diameter, while the height of each printing layer is within the range of layer height variation.

[0079] 1.4 Adjust the y-axis angle of the model so that all cross-sections are within the model printing angle limit.

[0080] 1.5 If the printing angle, layer height, or overhang distance of some parts of the segmentation result exceeds the limit, the layer height shall be finely adjusted between several consecutive cut surfaces to meet the limit requirement.

[0081] 2) Based on the placement angle and slicing angle results in step 1), choose whether to produce the corresponding printing mold; if no mold is needed, use a conventional printing platform.

[0082] 3) Model printing angle limitations: If printing from right to left, with the horizontal direction as the reference, printing can be performed on planes between the horizontal and those rotated 90° counterclockwise.

[0083] 4) Based on the slicing path, calculate the layer height, printing speed, and extrusion speed at each path point, and upload the data to the printing device for printing.

[0084] Step 1) The continuous variable angle printing method refers to the cumulative change in the overall printing angle by relying on the small changes in the angle of each slice to meet the printing requirements of different projection angles.

[0085] refer to Figure 1 As shown, the formula for calculating the cantilever angle of the model surface in step 1) is as follows:

[0086] α = 90° - arctan (h / P*D)

[0087] h = floor height, D = line width, P is the overhang ratio, which should be adjusted according to the situation.

[0088] Taking a 6mm nozzle as an example, if the printing parameters are a layer height h of 2mm, a line width D of 8mm, and an overhang ratio P of 0.5, then the maximum supported tilt angle α = 90° - arctan(2 / (0.5*D)) = 63.4° (based on the vertical direction). This result represents the maximum tilt angle of the model surface relative to the plane of a single-layer slice. Exceeding this angle will result in poor printing quality, such as poor contact between layers, collapse, and surface breakage. Therefore, an overhang ratio P of 0.3-0.4 is recommended for optimal printing results.

[0089] Taking a 6mm nozzle as an example, the print height of a single layer is preferably gradually varied between 1-4.8mm to achieve variations in the angle between multiple print layers. (Reference) Figure 3 As shown, the formula for calculating the angle that each layer can change is set as: β=arctan((a+b) / L), where a is the minimum layer height, b is the maximum layer height, and L is the distance between the maximum and minimum layer heights. Taking a minimum layer thickness of 1mm, a maximum layer thickness of 4mm, and a spacing of 500mm as an example, the maximum angle change capability provided by this layer is 0.344°.

[0090] Based on the printing process, determine the line width and nozzle size to be used. The formula for matching the extrusion speed, printing speed, and layer height is as follows:

[0091] Extrusion speed r = (h*D*ρ*v) / k

[0092] h is the floor height (mm), D is the line width (mm), and ρ is the material density (g / cm³). 3 k is the weight of material extruded per screw revolution (in grams).

[0093] Furthermore, if the slicing angle results in step 1) show that the protrusion angle of the model surface exceeds the maximum tilt angle, affecting the printing quality, then mold support is used. Small-area mold support parts are pre-printed on the printing platform, while large-area or complex mold support parts require additional mold fabrication. The fabricated mold is then 3D scanned and reconstructed, imported into the model, and repaired after comparing errors.

[0094] like Figure 7 and 8 As shown, this embodiment of the invention also provides an integral molding printing system, including:

[0095] The printing model processing unit 100 is used to: analyze the surface angle of the model, select the optimal placement angle, and select the slicing angle according to the protrusion angle of the model surface; if the model cannot be printed at a fixed angle, it selects the continuous variable angle printing method.

[0096] Select mold unit 200 to: select whether to produce the corresponding printing mold based on the placement and slicing results of printing model processing unit 100; if no mold is needed, use a conventional printing platform.

[0097] The printing angle confirmation unit 300 is used for: printing from right to left, with the horizontal direction as the reference, and printing on a plane between the horizontal and / or 90° counterclockwise rotation.

[0098] A variable-angle 3D printing device 400 is used for printing;

[0099] The print parameter calculation unit 500 is used to: calculate the layer height, printing speed and extrusion speed of each path point according to the slicing path, and upload them to the printing device 500.

[0100] The printing model processing unit 100 further includes a first subunit 101 for calculating the overhang angle of the model surface, using the following formula:

[0101] α = 90° - arctan (h / P*D)

[0102] h = floor height, D = line width, P is the overhang ratio, which should be adjusted according to the situation.

[0103] The height of a single printed layer is preferably gradually varied between 1-80% of the nozzle diameter to achieve variations in the angle between multiple printed layers. The formula for calculating the angle that can vary for each layer is: β=arctan((a+b) / L), where a is the minimum height of the layer, b is the maximum height of the layer, and L is the distance between the maximum and minimum height points.

[0104] Furthermore, the slicing angle of the printing model processing unit 100 is preferably 30-60°, and the standard layer height is preferably half the nozzle diameter.

[0105] When the standard placement of the model fails to meet the overhang limit, the printing model processing unit 100 needs to re-slice and verify the results. A second sub-unit 102 can also be set up to: rotate the model around the x-axis and y-axis respectively, and re-slice and verify; the x-axis rotation angle should be within ±180°, and the y-axis rotation angle within ±30°. If the results still do not meet the printing requirements, a third sub-unit 103 can be further set up to: perform UV line segmentation on the model to generate printing cut surfaces, with a standard layer height of half the nozzle diameter, while the height of each printing layer is within the layer height variation range; finally, adjust the y-axis angle of the model so that all cut surfaces are within the model printing angle limit range.

[0106] If the printing angle, layer height, or overhang distance in the segmentation result of the printing model processing unit 100 exceeds the limit, the layer height is finely adjusted between several consecutive cut surfaces to meet the limit requirement.

[0107] One possible approach for selecting mold unit 200 is as follows: if the slicing angle results from the printing model processing unit 100 show that the cantilever angle of the model surface exceeds the maximum tilt angle, then mold support is employed. Furthermore, small-area mold support components can be pre-printed on the printing platform, while large-area or complex mold supports require additional mold fabrication. The fabricated mold is then 3D scanned and reconstructed, imported into the model, and repaired after error comparison.

[0108] The printing parameter calculation unit 500 may further include an algorithm unit 501 for calculating the printing speed. The formula for the relationship between the extrusion speed and the layer height is: extrusion speed r = (h*D*ρ*v) / k, where h is the layer height, D is the line width, ρ is the material density, and k is the weight of material extruded per screw revolution.

[0109] refer to Figure 7 , Figure 8 One possible solution is a variable-angle 3D printing device (400).

[0110] The device includes a guide rail 401, a robot 402 with four or more axes, an extruder 403, a nozzle 404, a feeder 405, a printing platform 406, and a fan 407. The robot 402 is mounted on the guide rail 401 and moves freely. The extruder 403 is mounted on the end shaft of the robot 402. The nozzle 404 is connected to the end of the extruder 403, and the axis of the nozzle 404 forms an angle of 20-70° with the screw axis of the extruder 403. The feed pipe of the feeder 405 is connected to the barrel of the extruder 403. The fan 407 is mounted on the end wall of the extruder 403 and is used to cool the extruded material. The printing platform 406 is located below the extruder 403 and is used to support the printed parts and / or molds.

[0111] A further preferred embodiment is that, during printing, the axis of the nozzle 404 is adjusted to a 45° angle with the screw axis of the extruder 403, that is, the angle is fixed and the layers are printed at a horizontal tilt of 45°.

[0112] When printing very large parts, especially slender components, an external shaft 408 can be connected to the end shaft of the robot 402, and then the extruder 403 can be fixed to the external shaft 408 to achieve large-scale axial printing. The length of the external shaft 408 can be selected according to the actual situation; generally, a 10-meter external shaft can meet most needs.

[0113] Another preferred option is to install a dryer 409 between the hopper and the feed pipe of the conveyor 405, with the discharge port of the dryer 409 connected to the feed pipe.

[0114] Another preferred option is to install a suction machine 410, whose suction pipe is connected to the barrel of the extruder 403 to achieve automatic negative pressure feeding.

[0115] In addition, embodiments of the present invention also provide an apparatus or terminal for integral molding printing, including one or more processors and a storage device; the storage device is used to store one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the integral molding printing method as described in any of the first aspects above. It may further include a communication interface for communicating with other devices or communication networks.

[0116] Meanwhile, embodiments of the present invention also provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements an integral molding printing method as described in any of the first aspects above.

[0117] Those skilled in the art will understand that all or part of the steps provided by the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps in the method.

[0118] Print a like Figure 10 The component shown is 5m long, 1m wide, and 1.2m high. The hardware utilizes a six-axis robot with an additional 10m external axis to achieve large-scale axial printing. The angle between the extruder screw and nozzle is 45 degrees. A support rod connects to the base under the mold, securing the entire mold.

[0119] Reference process Figure 9 As shown in the steps of the above embodiments,

[0120] 1. Print using 8mm line width, with a base layer height of 4mm.

[0121] 2. Place the model upside down and slice it at a 45° tilt angle. Make a protrusion in the middle that extends beyond most of the model, with a maximum of 70 degrees, exceeding the limit by 10 degrees. Leave a hole in the protruding part for post-processing.

[0122] 3. The slicing angle needs to be gradually transitioned to 55°.

[0123] 4. Generate transition planes for sliced ​​planes at different angles.

[0124] 5. Use GRP material to make a support mold and place it on the printing platform. Use a laser scanner to scan the mold, create a point cloud model, compare the error with the model mold, and make repairs. For parts that cannot be repaired, make slight path adjustments.

[0125] 6. Calculate the slicing path. The slicing plane between 45° and 55° is approximately 1600mm, with approximately 400 printing layers. The angle change for each layer is 0.025°. Since the value is relatively small, the line connecting the centroids of the two slices can be simply used as the transition axis of the slicing surface. Set the printing speed to 0.15m / s and the material density to 1.2g / cm³. Program the screw speed at each path point according to the aforementioned formula to produce the final path program.

[0126] 7. Input the data into the printing device for printing.

[0127] The above are illustrative examples of preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A one-piece molding printing method, comprising the following steps: 1) Printed model processing: Based on the overall trend of the model, select the standard placement posture, then analyze the surface curvature characteristics of the model, slice it with a constant angle and layer height, and confirm whether the slicing result meets the overhang limit; if it does not meet the overhang limit, the model needs to be rotated along one or more axes and sliced ​​again to verify the result; 2) Based on the placement posture and slicing results determined in step 1), decide whether to produce the corresponding printing mold; If no mold is required, a standard printing platform can be used. 3) Model printing angle limitation: If printing from right to left, use the horizontal direction as the reference and print on a plane between the horizontal and / or 90° counterclockwise rotation. 4) Based on the slicing path, calculate the layer height, printing speed, and extrusion speed at each path point, and upload the data to the printing device for printing.

2. The integral molding printing method as described in claim 1, characterized in that: Step 1) To verify the results by slicing the model again, rotate the model around the x-axis and y-axis respectively, and then slice it again for verification. The rotation angle along the x-axis is within ±180°, and the rotation angle along the y-axis is within ±30°.

3. The integral molding printing method as described in claim 2, characterized in that: If the slicing results do not meet the printing requirements, the model is divided into UV lines to generate printing surfaces, while the height of each printing layer is within the range of layer height variation; finally, the y-axis angle of the model is adjusted so that all surfaces are within the model printing angle limit range.

4. The integral molding printing method as described in claim 3, characterized in that: If the printing angle, layer height, or overhang distance in the segmentation result exceeds the limit, the layer height is finely adjusted between several consecutive cut surfaces to meet the limit requirement.

5. The integral molding printing method as described in claim 1, characterized in that: The formula for calculating the projection angle of the model surface is as follows: α = 90° - arctan (h / P*D) h = floor height (mm), D = line width (mm); P is the overhang ratio.

6. The integral molding printing method as described in claim 1, characterized in that: The printing height of a single layer gradually varies between 1-80% of the nozzle diameter. The formula for calculating the angle that can vary for each layer is: β=arctan((a+b) / L), where a is the minimum layer height in the layer, b is the maximum layer height in the layer, and L is the distance between the maximum and minimum layer height points.

7. The integral molding printing method as described in claim 1, characterized in that: The formulas relating line width, nozzle size, extrusion speed, printing speed, and layer height are as follows: Extrusion speed r = (h*D*ρ*v) / k h is the floor height (mm), D is the line width (mm), and ρ is the material density (g / cm³). 3 v is the printing speed in m / s, and k is the weight of material extruded per screw revolution in g.

8. An integrated molding printing system, comprising: The printing model processing unit (100) is used to: select a standard placement posture according to the overall trend of the model, then analyze the curvature characteristics of the model surface, slice the model at a constant angle and layer height, and confirm whether the slicing result meets the overhang limit; if the overhang limit is not met, the model needs to be rotated along one or more axes and sliced ​​again to verify the result. Select mold unit (200) for: selecting whether to produce the corresponding printing mold based on the placement posture and slicing results determined by printing model processing unit (100); If no mold is required, a standard printing platform can be used. The printing angle confirmation unit (300) is used for: printing from right to left, with the horizontal direction as the reference, and printing in a plane between the horizontal and / or 90° counterclockwise rotation; A variable-angle 3D printing device (400) is used for printing; The print parameter calculation unit (500) is used to: calculate the layer height, print speed and extrusion speed of each path point according to the slice path, and upload them to the printing device (400).

9. The one-piece molding printing system as described in claim 8, characterized in that: The variable angle 3D printing equipment (400) includes: a guide rail (401), a robot (402) with four or more axes, an extruder (403), a nozzle (404), a feeder (405), a printing platform (406), and a fan (407). The robot (402) is mounted on the guide rail (401) and moves freely. The extruder (403) is mounted on the end shaft of the robot (402). The nozzle (404) is connected to the end of the extruder (403), and the axis of the nozzle (404) forms an angle of 20-70° with the screw axis of the extruder (403). The feed pipe of the feeder (405) is connected to the barrel of the extruder (403). The fan (407) is mounted on the end wall of the extruder (403) and is used to cool the extruded material. The printing platform (406) is located below the extruder (403) and is used to support the printed parts and / or molds.

10. An apparatus or terminal for integral molding printing, comprising one or more processors and a storage device; the storage device being used to store one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the integral molding printing method as described in any one of claims 1-7.

11. A computer-readable storage medium storing a computer program that, when executed by a processor, implements the integral molding printing method according to any one of claims 1-7.

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