3D printing system for material taking training of doctors and printing method of 3D printing system
By adopting a cyclic switching mechanism and multi-spec nozzle design in the 3D printing system, the problems of slow printing speed and rough model in the prior art are solved, and efficient and accurate human body model printing is achieved.
Patent Information
- Application Number
- CN202510051696.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2025-04-29
AI Technical Summary
When existing 3D printing technology produces high-precision mannequins, printers with smaller nozzle apertures are slower, while replacing nozzles with larger apertures leads to rough models, making it difficult to meet the fine needs of doctor training.
A 3D printing system for doctor training is designed, using a cycle switching mechanism and multiple specifications of nozzles. The nozzle specifications and locations are obtained through the control module, and the printheads of different specifications and apertures are replaced according to the fine needs of the model.
It achieves the improvement of printing efficiency while ensuring printing accuracy, and meets the high-precision model printing needs required for doctor training.
Smart Images
Figure CN119898028A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of 3D printing technology, and in particular to a 3D printing system and a printing method thereof for obtaining materials for doctor training. Background Art
[0002] Doctors need to use various structures such as hearts, blood vessels, and tissues as specimens for teaching when taking pathological samples for training. However, these structures are in short supply, and using real organs or tissues for training can easily lead to waste of biomedical equipment. 3D printing technology provides a new solution to the above problems.
[0003] 3D printing technology refers to a cumulative manufacturing technology that can create three-dimensional objects by printing layers of adhesive materials. The human body models printed with 3D printing technology can contain rich details and have intricate skin meshes, bones and other structures for teaching purposes.
[0004] From the above, it can be seen that many human body structure models used for doctor training are complex in composition, with fine structures and rough homogeneous structures interlaced. Under this premise, if high-precision models are to be produced, a printer with a smaller nozzle aperture should be selected. However, this printing structure has a slow speed; and if a nozzle printer with a larger aperture is replaced, the model will be relatively rough. Therefore, this application proposes a new technical solution. Summary of the invention
[0005] In order to meet printing needs while improving printing efficiency, the present application provides a 3D printing system and a printing method for doctor training materials.
[0006] This application provides a 3D printing system for doctor training and sampling, which adopts the following technical solutions: A 3D printing system for obtaining materials for doctor training comprises a printer body, a print head of the printer body comprises a discharge module and a nozzle connected to a discharge port of the discharge module, and is characterized in that: it also comprises a control module and a circulation switching mechanism, a circulation switching mechanism is installed at the lower part of the discharge module, the circulation switching mechanism comprises a disc and a rotating assembly driving the disc to rotate, a central shaft is fixed axially to the disc, the central shaft is rotatably connected to the discharge module, and the rotating assembly is located between the disc and the discharge module; There are multiple nozzles with different aperture sizes, and the multiple nozzles are installed on the disc around the center of the disc. The discharge port of the discharge module is connected to a material guide structure, and the material guide structure includes at least one discharge port, and the discharge port is located directly above the moving track of the nozzle; The rotating assembly is electrically connected to a control module, and the control module is configured as follows: Obtain the specifications of each nozzle, the radius r of the disk, and the position of the nozzle on the disk (Xn, Yn, Zn), and record them as fixed properties of the print head; where n is the serial number of the nozzle; Obtain the matching relationship between the nozzle and each component in the three-dimensional model, and store it in the database; Acquire a three-dimensional model of the target to be printed, identify and determine the initial printing position and the nozzle matched for the initial printing, and generate a print head movement control instruction and a nozzle switching control instruction; wherein the nozzle switching control instruction includes the angle α of the disk to be rotated, and the angle α to be rotated is calculated based on the fixed properties of the print head; If the printing action is currently being executed, the object that needs to be printed after the current time t1 is identified, and the database is searched to determine the matching nozzle, and a nozzle switching control instruction is generated accordingly; wherein t1 is a preset value.
[0007] Optionally, a flushing mechanism for providing hot solution to clean residues in the nozzle is provided above the disc, and the flushing mechanism includes a main pipe, multiple flushing pipes and a water supply unit, one end of the main pipe is connected to the water outlet end of the water supply unit, and the other end is connected to one end of the flushing pipe, and the other ends of the multiple flushing pipes are distributed directly above the moving trajectory of the nozzle.
[0008] Optionally, the bottom of the disc is detachably connected to a collecting box, and the nozzle moved to the position just below the discharge port of the material guiding structure is located outside the collecting box. The collecting box is externally connected to a collecting assembly, and the collecting assembly includes a collecting pipe and a pumping unit. One end of the collecting pipe is connected to the collecting box, and the other end is connected to the pumping end of the pumping unit. The water outlet end of the pumping unit is connected to a waste box, and the height of the waste box is greater than the height of the collecting box.
[0009] Optionally, the rotating assembly includes gear one, gear two, a motor and a rotary encoder. A fixed seat is provided at the bottom of the discharging module, the motor is installed on the fixed seat, the output end of the motor and the rotating shaft of gear two are fixed, the center of gear one is coaxially fixed with the central axis, gear one and gear two are meshed, the rotary encoder is installed at the end of the central axis, and the motor and the rotary encoder are electrically connected to the control module.
[0010] Optionally, a mounting groove is dug inside the central axis, an electric cylinder is installed in the mounting groove, the telescopic end of the electric cylinder extends out of the notch of the mounting groove and is fixed to the center of the disc, a slide groove is dug inside the fixed seat along the height direction, a slider is slidably connected in the slide groove, and the motor is installed on the slider.
[0011] Optionally, the nozzle center deviates from the center of the print head, and the control module is configured as follows: Get the coordinates of the print head at the current position ; Get the coordinates of the nozzle directly below the discharge port of the discharge module ; Calculate the difference X1-X between the center axis of the print head and the center axis of the nozzle on the X axis and define it as d1; Calculate the difference Y1-Y between the center axis of the print head and the center axis of the nozzle on the Y axis and define it as d2; Get the coordinates (Xt, Yt, Zt) of the object to be printed after the current time t1; Coordinates of the print head based on the current position , the coordinates (Xt, Yt, Zt) of the object to be printed after the current moment t1, the difference d1 between the center axis of the print head and the center axis of the nozzle on the X-axis, and the difference d2 between the center axis of the print head and the center axis of the nozzle on the Y-axis, calculate and analyze the moving distance of the print head.
[0012] Optionally, the discharging module is electrically connected to a control module, and the control module is configured as follows: Obtain the apertures of the spray holes of the two nozzles before and after replacement; Based on the diameter of the spray hole and the area formula of the circle, the difference ratio of the discharge flow rate of the replaced nozzle is calculated and analyzed; Based on the analysis of the difference in discharge flow rate ratio of the replaced nozzle, the discharge flow rate ratio is controlled and adjusted.
[0013] This application provides a 3D printing method for doctor training and sampling, using the following technical solutions: A 3D printing method for doctor training materials, applied to the 3D printing system for doctor training materials as claimed in any one of claims 1 to 7 to perform printing work, comprising the following steps: S1. Preparation before printing, which includes: Prepare the nozzles needed for this printing and enter the specifications and installation positions of the nozzles into the control module; Prepare the raw materials needed for this printing and fix them at the feed end; S2. Printing model, which includes: The 3D printing system used for doctor training can monitor the printing progress in real time and adjust the printing accuracy and speed in time; S3, post-printing processing, which includes: Polish the surface of the model after printing; Clean the printer and clean or replace the collection box.
[0014] In summary, the present application includes the following beneficial technical effects: a circulating switching mechanism is added under the discharge module, and nozzles of multiple specifications are installed, and print heads of different specifications and apertures are replaced according to the specific and detailed requirements of the model, thereby meeting the printing requirements of the model used by doctors for sampling. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the overall structure of this application; Figure 2 yes Figure 1 A magnified view of part A; Figure 3 is a control module connection diagram of the present application; Figure 4 is a flow chart of the method of the present application.
[0016] Explanation of the reference numerals: 1. Print head; 2. Discharge module; 21. Material guide structure; 3. Nozzle; 4. Circulation switching mechanism; 5. Control module; 6. Flushing pipe; 7. Collection pipe; 41. Disc; 412. Center axis; 413. Electric cylinder; 42. Rotating assembly; 43. Collection box; 421. Gear 1; 422. Gear 2; 423. Motor; 424. Fixed seat; 425. Rotary encoder. DETAILED DESCRIPTION
[0017] The following is combined with Figure 1-4 This application is described in further detail.
[0018] The embodiment of the present application discloses a 3D printing system for obtaining materials for doctor training.
[0019] Reference Figure 1 and Figure 2 The 3D printing system for doctor training materials includes a printer body and a control module 5, wherein the printer is an FDM (fused deposition modeling) printer used in the prior art, which will not be described in detail here. The print head 1 of the printer body includes a discharge module 2 and a nozzle 3, and a circulation switching mechanism 4 is installed at the lower part of the discharge module 2. The circulation switching mechanism 4 is used to replace the nozzle 3 used, which includes a disc 41 and a rotating assembly 42 that drives the disc 41 to rotate. The disc 41 is axially fixed with a central shaft 412, and the central shaft 412 is rotatably connected to the discharge module 2. The housing of the discharge module 2 may be provided with a groove, and one end of the central shaft 412 is installed in the groove, and the notch of the groove can be fixed with a limit plate to prevent the central shaft 412 from running out by bolts and nuts, so that one end of the central shaft 412 can be rotatably connected to the discharge module 2, and the rotating assembly 42 is located between the disc 41 and the discharge module 2.
[0020] There are multiple nozzles 3, and the apertures of the nozzles 3 are different, so that the different precision requirements for printing organs, tissues, etc. can be met as much as possible. Multiple nozzles 3 are installed on the disk 41 around the center of the disk 41. The discharge port of the discharge module 2 is connected to the guide structure 21. The guide structure 21 can be a multi-section pipeline and one end of the pipeline is connected to the discharge module 2. A section of the pipeline extending from the discharge module 2 is fixed by a bracket. The pipeline includes at least one discharge port and the discharge port is located directly above the moving track of the nozzle 3. The discharge port of the pipeline can be a truncated cone, and a rubber ring is fixed around the outside, so that the discharge port is easy to insert into the nozzle 3 and guide the printing material into the nozzle 3. It can be understood that the discharge port of the pipeline is a hard pipe structure, which is more convenient for inserting the nozzle 3, and the drainage section of the pipeline is a hose structure, which is more convenient for the bracket to fix its direction.
[0021] The rotating assembly 42 is electrically connected to the control module 5. The control module 5 may be an external host with a display. The control module 5 is configured as follows: The specifications of each nozzle 3, the radius r of the disk 41 and the position of the nozzle 3 on the disk 41 (Xn, Yn, Zn) are obtained, and recorded as fixed attributes of the print head 1; wherein n is the serial number of the nozzle 3, for example: 1, 2, 3... wherein the specifications of each nozzle 3, the radius of the disk 41 and the position of the nozzle 3 can be entered in advance by the staff, and the position of the nozzle 3 needs to correspond to its serial number and be entered together, so as to facilitate the subsequent control operation of the control module 5. After entering, the above information is recorded as a fixed attribute of the print head 1, so as to facilitate the subsequent analysis of when to replace the nozzle 3, which nozzle 3 to replace and how to move the position of the print head 1.
[0022] The matching relationship between the nozzle 3 and each component in the three-dimensional model is obtained and stored in the database; wherein the three-dimensional model is established in advance or selected from the model library in advance, and by analyzing the model, it can be known what specifications of the nozzle 3 are needed when a certain tissue or a certain section needs to be printed.
[0023] The three-dimensional model of the target to be printed is obtained, and the initial printing position and the nozzle 3 matched by the initial printing are identified and determined, and the movement control instruction of the print head 1 and the switching control instruction of the nozzle 3 are generated; wherein the initial printing position is the starting point when printing this model, and the nozzle 3 matched by the initial printing is matched according to the accuracy required when printing the component of the organ or tissue printed at the starting point, such as: if the part printed at the starting point is a relatively fine organ component such as a blood vessel, a nozzle 3 with an aperture of 0.1 mm can be selected. After the initial printing position and the nozzle 3 matched by the initial printing are determined, it is necessary to analyze the subsequent printing position and the nozzle 3 used, so as to generate the movement control instruction of the print head 1 and the switching control instruction of the nozzle 3.
[0024] Among them, the nozzle 3 switching control instruction includes the rotation angle α of the disk 41. The rotation angle α is calculated based on the fixed properties of the print head 1 and can be calculated according to the number of nozzles 3 distributed on the disk 41. For example, if there are 6 nozzles 3 on the disk 41, the rotation angle required to replace adjacent nozzles 3 is 360°÷6, that is, 60°. If the replaced nozzles 3 are not adjacent, it is calculated according to the number of nozzles 3 spaced apart. Taking 6 nozzles 3 as an example, if there is 1 nozzle 3 between the rotated nozzle 3 and the nozzle 3 before rotation, the rotation is 120°.
[0025] If a printing action is currently being performed, the object that needs to be printed at the current time t1 is identified, and the database is searched to determine the matching nozzle 3, and a corresponding nozzle 3 switching control instruction is generated; wherein, t1 is a preset value, t1 can be 0.1s or 0.5s, which can be determined according to the printing speed. If the printing accuracy requirement changes after t1, the rotating component 42 can be controlled to rotate to switch the nozzle 3.
[0026] Reference Figure 2 A flushing mechanism for providing a hot solution to clean the residue in the nozzle 3 is arranged above the disc 41, wherein the hot solution can be hot water, and the flushing mechanism includes a main pipeline (not shown in the figure), a plurality of flushing pipes 6 and a water supply unit (not shown in the figure), and the water supply unit can be an external water tank, one end of the main pipeline is connected to the water outlet end of the water supply unit, and the other end is connected to one end of the flushing pipe 6 through a multi-way pipe, and the other ends of the plurality of flushing pipes 6 are distributed directly above the moving track of the nozzle 3. This arrangement makes it easier for the hot solution in the flushing pipe 6 to flow into the nozzle 3 to clean the inside of the nozzle 3, thereby reducing the residual printing material in the nozzle 3 as much as possible, because the printing materials are divided into different colors, and after the nozzle 3 is replaced, some of the printing materials at the original position will remain. If it is not cleaned, the next time the nozzle 3 is used, it will affect the accuracy of the printed model. Therefore, the above arrangement can reduce the impact on the model printing and increase the printing accuracy.
[0027] Reference Figure 2 A collecting box 43 is detachably connected to the bottom of the disc 41, and the nozzle 3 moved to the bottom of the material discharge port of the material guide structure 21 is located outside the collecting box 43. The collecting box 43 can be fixed to the bottom of the disc 41 by bolts and nuts, and the collecting box 43 can be fan-shaped when viewed from above, covering a nozzle 3 that needs to be cleaned; or it can be only the nozzle 3 that is not covered at the material discharge port of the material guide structure 21, and the remaining nozzles 3 are covered.
[0028] The collecting box 43 is externally connected to a collecting assembly, which includes a collecting tube 7 and a pumping unit (not shown in the figure). One end of the collecting tube 7 is connected to the collecting box 43, and the other end is connected to the pumping end of the pumping unit. The outlet end of the pumping unit is connected to a waste box for collecting the extracted waste water, wherein the position of the waste box is higher than the position of the collecting box 43, and the collecting tube 7 is fixedly installed by a bracket so that it will not hinder the printer from printing. Through the above arrangement, the waste cleaned out of the nozzle 3 can be collected and centrally processed, effectively avoiding the waste overflow in the collecting box 43 and keeping the printer clean.
[0029] Reference Figure 2 The rotating assembly 42 includes a gear 1 421, a gear 2 422, a motor 423 and a rotary encoder 425. The diameter of the gear 1 421 is larger than the diameter of the gear 2 422, and the gear 1 421 meshes with the gear 2 422. A fixing seat 424 is provided at the bottom of the discharging module 2. The motor 423 can be installed on the fixing seat 424 by bolts and nuts. The output end of the motor 423 is fixed to the rotating shaft of the gear 2 422. The center of the gear 1 421 is coaxially fixed with the central axis 412. Since the disk 41 is fixed on the central axis 412, the motor 423 drives the gear 2 422 to rotate through the meshing of the gear 1 421 and the gear 2 422, that is, drives the gear 1 421 and even the disk 41 to rotate. And through the cooperation of the gear 1 421 and the gear 2 422, the rotation speed of the gear 1 421 and even the disk 41 can be reduced, which is more suitable for the operation of the printer. The rotary encoder 425 is installed at the end of the central shaft 412, and the rotary encoder 425 and the motor 423 are electrically connected to the control module 5. The rotary encoder 425 can be used to know the rotation angle of the central shaft 412, thereby knowing the rotation angle of the disc 41, so that the control module 5 can determine the rotation angle and issue an instruction to replace the nozzle 3 on the disc 41.
[0030] Reference Figure 2 A mounting groove is dug inside the central axis 412, and 413 is installed in the mounting groove. The electric cylinder 413 can be fixed in the mounting groove by bolts and nuts. The telescopic end of the electric cylinder 413 faces downward and extends out of the notch of the mounting groove. The telescopic end of the electric cylinder 413 is fixed to the center of the disc 41, which is convenient for driving the disc 41 to move up and down. A sliding groove is dug inside the fixed seat 424 on which the power supply machine 423 is installed along the height direction, and a slider is slidably connected in the sliding groove. The motor 423 is installed on the slider. When the electric cylinder 413 drives the disc 41 to move up and down, the motor 423 can be driven to move up and down at the same time, thereby not hindering the work of the electric cylinder 413.
[0031] Reference Figure 2 and Figure 3Since the nozzle 3 is installed around the center of the disk 41, the center of the nozzle 3 deviates from the center of the print head 1, that is, the central axis 412 of the nozzle 3 is not flush with the axis of the print head 1, the control module 5 is configured as follows: Get the coordinates (X, Y, Z) of print head 1 at the current position; Get the coordinates (X1, Y1, Z1) of the nozzle 3 directly below the discharge port of the discharge module 2; because the nozzle 3 directly below the discharge port of the discharge module 2 is the nozzle 3 used for printing, the movement amount needs to be based on the coordinates of the nozzle 3, and because the coordinates of the nozzle 3 are basically the same, it only needs to be obtained and calculated once.
[0032] The difference X1-X between the center axis 412 line of the print head 1 and the center axis 412 line of the nozzle 3 on the X-axis is calculated and defined as d1; wherein d1 is the additional movement amount required after the print head 1 moves in the X-axis direction.
[0033] The difference Y1-Y between the center axis 412 line of the print head 1 and the center axis 412 line of the nozzle 3 on the Y axis is calculated and defined as d2; wherein d2 is the additional movement amount required after the print head 1 moves in the Y axis direction.
[0034] Since the print head 1 and the disk 41 are coaxially fixed, the distance difference between the print head 1 and the nozzle 3 on the X-axis and the Y-axis can be obtained based on the coordinates of the position of the nozzle 3 on the disk 41 and the coordinates of the print head 1. Because the distance between the two axes only requires the vertical straight line distance, the Z axis can be ignored. For example: the coordinates of the nozzle 3 directly below the discharge port of the discharge module 2 are (3,4,0), and the coordinates of the print head 1 are (0,0,0), d1 is 3, and d2 is 4.
[0035] Get the coordinates (Xt, Yt, Zt) of the object to be printed after the current time t1; the time t1 can be 0.1s or 0.5s, which is preset by the staff according to the printing speed.
[0036] Based on the coordinates (X, Y, Z) of print head 1 at the current position, the coordinates (Xt, Yt, Zt) of the object to be printed after the current time t1, the difference d1 between the center axis 412 line of print head 1 and the center axis 412 line of nozzle 3 on the X axis, and the difference d2 between the center axis 412 line of print head 1 and the center axis 412 line of nozzle 3 on the Y axis, the moving distance of print head 1 is calculated and analyzed. Example: The coordinates of print head 1 at the current position are (1, 1, 1), and the coordinates of the object to be printed after the current time t1 are (5, 6, 7). If d1 is 3 and d2 is 4, then print head 1 needs to move 5-(1+3)=1 on the X axis, that is, it only needs to move 1, and print head 1 needs to move 6-(1+4)=1 on the Y axis, that is, print head 1 only needs to move to the coordinate position (2, 2, 7) in the end.
[0037] According to this configuration, the moving distance of the print head 1 can be changed according to the specific position of the nozzle 3, thereby making the printing more accurate.
[0038] Reference Figure 2 and Figure 3 The discharging module 2 is electrically connected to the control module 5, and the control module 5 is configured as follows: The apertures of the spray holes of the two nozzles 3 before and after replacement are obtained. According to the above, the specifications of the nozzles 3 are recorded in advance, that is, the specifications of the nozzles 3 recorded in advance can be obtained to obtain the apertures of the spray holes.
[0039] The phase difference ratio of the discharge flow rate of the replaced nozzle 3 is calculated and analyzed based on the formula of the aperture of the spray hole and the area of the circle; if the aperture of the spray hole before replacement is smaller, and the aperture of the spray hole after replacement is larger, then according to the original flow rate, the discharge speed for the aperture of the replaced spray hole will be slower. For example: the aperture of the spray hole of the nozzle 3 before replacement is 0.2mm, and the aperture of the spray hole of the replaced nozzle 3 is 0.4mm. According to A=πr^2, it can be known that A is 0.01π before replacement and A is 0.04π after replacement. Then, if the original flow rate is still used for discharge, it may cause insufficient discharge of the replaced nozzle 3. The discharge speed of the replaced nozzle 3 is relatively slow. At this time, the speed needs to be adjusted to 4 times the original speed.
[0040] Based on the analysis of the difference in the discharge flow rate of the replaced nozzle 3, the discharge flow rate ratio is controlled and adjusted. According to the above settings, it can be ensured that the discharge of the nozzle 3 is more uniform, thereby reducing the roughness of the print and making the printed model more accurate and complete. And according to this setting, when the nozzle 3 is replaced, the discharge flow rate of the present application is adjusted, which can not only meet the different requirements of the model for accuracy, but also ensure the fineness and integrity of the model printed by the present application as much as possible.
[0041] The embodiment of the present application also discloses a 3D printing method for obtaining samples for doctor training.
[0042] Reference Figure 4 The 3D printing method for doctor training includes the following steps: S1. Preparation before printing, which includes: Prepare the nozzle 3 required for this printing, and enter the specifications and installation position of the nozzle 3 into the control module 5; this step can be completed in advance by the staff. Since there are many specifications and quantities of the nozzle 3, this printing will not necessarily use every specification of the nozzle 3, and different models may use nozzles 3 of different specifications, so they can be installed in advance according to the needs of this printing. After installation, the specifications and installation position of this installation will be entered into the control module 5 for subsequent use.
[0043] Prepare the raw materials needed for this printing and fix them at the feed end; since the colors of the internal structures of different models are different, raw materials of various colors will be used. This step prepares raw materials of different colors in advance according to the needs of the model.
[0044] S2. Printing model, which includes: The 3D printing system used for doctor training monitors the printing progress in real time and adjusts the printing accuracy and speed in time; the printing accuracy can be analyzed by the control module 5 and adjusted by replacing different nozzles 3, while the printing speed can be judged and adjusted by the staff according to specific needs, such as: whether the nozzle 3 can be replaced in time at the printing speed, whether the replaced nozzle 3 can connect to the work of the previous nozzle 3, etc.
[0045] S3, post-printing processing, which includes: Polish the surface of the model after printing; since some printed models have a rough surface or particles, they can be polished.
[0046] Clean the printer and clean or replace the collection box 43. Since waste materials and other residues may be generated during printing, the printer needs to be cleaned for future use. The replacement of the collection box 43 can be determined based on the use of the collection box 43, such as whether the residual materials attached to the inner wall are too much or cannot be cleaned, so as to determine whether the collection box 43 needs to be replaced.
[0047] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A 3D printing system for obtaining materials for doctor training, comprising a printer body, wherein a print head (1) of the printer body comprises a discharge module (2) and a nozzle (3) connected to a discharge port of the discharge module (2), characterized in that: It also comprises a control module (5) and a circulation switching mechanism (4), wherein the circulation switching mechanism (4) is installed at the bottom of the discharge module (2), and the circulation switching mechanism (4) comprises a disc (41) and a rotating assembly (42) for driving the disc (41) to rotate, wherein the disc (41) is axially fixed with a central shaft (412), the central shaft (412) is rotatably connected to the discharge module (2), and the rotating assembly (42) is located between the disc (41) and the discharge module (2); There are a plurality of nozzles (3) and the apertures of the nozzles (3) are of different sizes. The plurality of nozzles (3) are mounted on the disk (41) around the center of the disk (41). The discharge port of the discharge module (2) is connected to a material guide structure (21). The material guide structure (21) includes at least one discharge port and the discharge port is located directly above the moving track of the nozzle (3). The rotating assembly (42) is electrically connected to a control module (5), and the control module (5) is configured as follows: Obtaining the specifications of each nozzle (3), the radius r of the disk (41), and the position (Xn, Yn, Zn) of the nozzle (3) on the disk (41), and recording them as fixed attributes of the print head (1); wherein n is the serial number of the nozzle (3); Obtaining the matching relationship between the nozzle (3) and each component in the three-dimensional model, and pre-storing it in a database; Acquire a three-dimensional model of the target to be printed, identify and determine the initial printing position and the nozzle (3) matched for the initial printing, and generate a print head (1) movement control instruction and a nozzle (3) switching control instruction; wherein the nozzle (3) switching control instruction includes a rotation angle α of the disk (41), and the rotation angle α is calculated based on a fixed attribute of the print head (1); If a printing action is currently being executed, the object to be printed after the current time t1 is identified, and a matching nozzle (3) is searched in the database, and a nozzle (3) switching control instruction is generated accordingly; wherein t1 is a preset value.
2. The 3D printing system for doctor training and sampling according to claim 1, characterized in that: A flushing mechanism for providing hot solution to clean residues in the nozzle (3) is arranged above the disc (41), the flushing mechanism comprising a main pipeline, a plurality of flushing pipes (6) and a water supply unit, one end of the main pipeline being connected to a water outlet of the water supply unit, and the other end being connected to one end of the flushing pipe (6), the other ends of the plurality of flushing pipes (6) being distributed directly above the moving track of the nozzle (3).
3. The 3D printing system for doctor training and sampling according to claim 2, characterized in that: The bottom of the disc (41) is detachably connected to a collecting box (43); the nozzle (3) moved to the position directly below the discharge port of the material guide structure (21) is located outside the collecting box (43); the collecting box (43) is externally connected to a collecting assembly, the collecting assembly comprising a collecting pipe (7) and a pumping unit; one end of the collecting pipe (7) is connected to the collecting box (43), and the other end is connected to a pumping end of the pumping unit; the water outlet end of the pumping unit is connected to a waste box, the height of the waste box being greater than the height of the collecting box (43).
4. The 3D printing system for doctor training and sampling according to claim 3, characterized in that: The rotating assembly (42) comprises a gear 1 (421), a gear 2 (422), a motor (423) and a rotary encoder (425); a fixing seat (424) is provided at the bottom of the discharging module (2); the motor (423) is mounted on the fixing seat (424); the output end of the motor (423) is fixed to the rotating shaft of the gear 2 (422); the center of the gear 1 (421) is coaxially fixed to the central shaft (412); the gear 1 (421) and the gear 2 (422) are meshed; the rotary encoder (425) is mounted on the end of the central shaft (412); and the motor (423) and the rotary encoder (425) are electrically connected to the control module (5).
5. The 3D printing system for doctor training and sampling according to claim 4, characterized in that: A mounting groove is excavated inside the central shaft (412), an electric cylinder (413) is installed in the mounting groove, a telescopic end of the electric cylinder (413) extends out of the notch of the mounting groove and is fixed to the center of the disc (41), a sliding groove is excavated inside the fixing seat (424) along the height direction, a slider is slidably connected in the sliding groove, and the motor (423) is installed on the slider.
6. The 3D printing system for doctor training and sampling according to claim 5, characterized in that: The center of the nozzle (3) deviates from the center of the print head (1), and the control module (5) is configured as follows: Get the coordinates (X, Y, Z) of the print head (1) at the current position; Obtain the coordinates (X1, Y1, Z1) of the nozzle (3) directly below the discharge port of the discharge module (2); Calculate the difference X1-X between the center axis (412) line of the print head (1) and the center axis (412) line of the nozzle (3) on the X-axis, and define it as d1; Calculate the difference Y1-Y between the center axis (412) line of the print head (1) and the center axis (412) line of the nozzle (3) on the Y axis, and define it as d2; Get the coordinates (Xt, Yt, Zt) of the object to be printed after the current time t1; Based on the coordinates (X, Y, Z) of the print head (1) at the current position, the coordinates (Xt, Yt, Zt) of the object to be printed after the current time t1, the difference d1 between the center axis (412) line of the print head (1) and the center axis (412) line of the nozzle (3) on the X axis, and the difference d2 between the center axis (412) line of the print head (1) and the center axis (412) line of the nozzle (3) on the Y axis, the movement distance of the print head (1) is calculated and analyzed.
7. The 3D printing system for doctor training according to claim 6, characterized in that: The discharging module (2) is electrically connected to the control module (5), and the control module (5) is configured as follows: Obtaining the diameters of the spray holes of the two spray heads (3) before and after replacement; The phase difference ratio of the discharge flow rate of the replaced nozzle (3) is calculated and analyzed based on the diameter of the spray hole and the area formula of the circle; Based on the analysis of the difference in the discharge flow rate ratio of the replaced nozzle (3), the discharge flow rate ratio is controlled and adjusted.
8. A 3D printing method for obtaining samples for doctor training, characterized in that: The 3D printing system used for doctor training and obtaining materials as claimed in any one of claims 1 to 7 performs printing work, comprising the following steps: S1. Preparation before printing, which includes: Prepare the nozzle (3) required for the current printing and input the specification and installation position of the nozzle (3) into the control module (5); Prepare the raw materials needed for this printing and fix them at the feed end; S2. Printing model, which includes: The 3D printing system used for doctor training can monitor the printing progress in real time and adjust the printing accuracy and speed in time; S3, post-printing processing, which includes: Polish the surface of the model after printing; Clean the printer and clean or replace the collection box (43).