3D printing system based on DLP technology

Abstract

The utility model discloses a 3D printing system based on the DLP technology, which comprises a material groove module provided with a resin groove and a tray and a projection assembly located on the upper side of the material groove module, and the projection assembly comprises a light source, a DMD chip and an optical lens. According to the 3D printing system, the height of the tray is accurately adjusted through the Z-axis lifting mechanism, the coordinate position of the projection assembly on a printing face is accurately controlled through the XY plane movement mechanism, dynamic image projection of the projection assembly is achieved, the 3D printing system can meet the requirement for large-size machining, and the machining efficiency of the 3D printing system is improved. The industrial control module controls the Z-axis lifting mechanism to drive the tray to move in the z direction according to the forming data information, and the XY plane movement mechanism controls the coordinate position of the projection assembly on the printing face, so that the pattern projected by the projection assembly, the position of the projection assembly and the height of the tray are matched, layer-by-layer printing and photosensitive resin curing of the 3D printing system are achieved, and the printing quality is improved. And a high-precision 3D formed part is obtained.

Description

TECHNICAL FIELD

[0001] The utility model relates to 3D printing field especially, and it is 3D printing system based on DLP technique. BACKGROUND

[0002] The core of DLP technology is DMD chip. 3D printing based on DMD scanning has the advantages of high material utilization, fast forming speed, no moving nozzle, and no blockage and misalignment commonly seen in other technologies.

[0003] The existing light-curing 3D forming machine based on DMD (Digital Micromirror Device) is based on static pattern projection, and its basic principle is projector technology. In the case of pursuing high precision, the forming size is greatly limited. If large-size forming is to be realized, the projection spot area needs to be enlarged, which will seriously affect the forming precision. UTILITY MODEL CONTENT

[0004] To solve the above problems, the utility model provides a 3D printing system based on DLP technology, which can realize dynamic projection of the projection assembly and meet large-size processing of the 3D printing system.

[0005] To achieve one of the purposes of the utility model, the utility model provides a 3D printing system based on DLP technology, which comprises:

[0006] The trough module comprises a resin tank for containing liquid photosensitive resin and a tray for carrying the formed part.

[0007] The projection assembly is arranged on the upper side of the trough module and comprises a light source, a DMD chip, and an optical lens.

[0008] The motion control assembly comprises:

[0009] The Z-axis lifting mechanism drives the tray to move in the vertical direction.

[0010] The XY plane motion mechanism controls the coordinate position of the projection assembly in the printing surface.

[0011] The industrial control module is electrically connected to the motion control assembly and the projection assembly.

[0012] Further, the projection assembly comprises a DMD driving module for controlling the projection imaging of the DMD chip, and the DMD driving module is electrically connected to the industrial control module.

[0013] Further, the XY plane motion mechanism comprises a stepping module for driving the projection assembly to move in the x direction and a scanning module for driving the projection assembly to move in the y direction.

[0014] Further, the step module and the scanning module each include:

[0015] A guide rail, the guide rails of the step module and the scanning module are perpendicular to each other;

[0016] A first control module for receiving signals of the industrial control module;

[0017] A first drive module for receiving signals of the first control module;

[0018] A first motor for receiving driving signals of the first drive module;

[0019] A first transmission module driven by the first motor, and driving the projection assembly to slide along the step guide rail or the scanning guide rail.

[0020] Further, the 3D printing system further includes a position synchronization module electrically connected with the industrial control module, the position synchronization module is used for receiving position information of the scanning module, and transmitting a position synchronization signal to the DMD driving module.

[0021] Further, the step module includes a step guide rail extending along an x direction, the scanning module includes a first scanning guide rail and a second scanning guide rail oppositely arranged and extending along a y direction, the step guide rail is slidably connected to the first scanning guide rail and the second scanning guide rail at two ends respectively, and the projection assembly is slidably connected to the step guide rail.

[0022] Further, after the projection assembly is installed on the step guide rail, the DMD chip and the step guide rail form an inclined scanning angle θ.

[0023] Further, the Z-axis lifting mechanism includes:

[0024] A lifting control module for receiving signals of the industrial control module;

[0025] A lifting drive module for receiving signals of the lifting control module;

[0026] A lifting motor for receiving driving signals of the lifting drive module;

[0027] A lifting transmission module driven by the lifting motor, and driving the tray to move along the Z-axis.

[0028] Further, the lifting transmission module includes a lead screw connected to an output end of the lifting motor, a screw block matched with the lead screw, a support plate connected to the screw block, and a support frame connected to the support plate, and the tray is fixed to one side of the support frame close to the resin tank.

[0029] Furthermore, the light source includes a semiconductor laser light source or an ultraviolet LED light source.

[0030] This utility model's 3D printing system uses a Z-axis lifting mechanism to precisely adjust the tray height and an XY-plane motion mechanism to precisely control the coordinate position of the projection component on the printing surface, enabling dynamic projection and allowing the 3D printing system to handle large-size processing and improve processing efficiency. The industrial control module controls the Z-axis lifting mechanism to move the tray in the Z-direction and the XY-plane motion mechanism to control the coordinate position of the projection component on the printing surface, ensuring that the projected image, the position of the projection component, and the height of the tray are matched. This allows the 3D printing system to print and cure photosensitive resin layer by layer, obtaining high-precision 3D molded parts. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of a 3D printing system based on DLP technology in a specific embodiment of this utility model;

[0032] Figure 2 for Figure 1 Schematic diagram of the Z-axis lifting mechanism and trough module;

[0033] Figure 3 This is a control principle diagram of a 3D printing system based on DLP technology in a specific embodiment of this utility model;

[0034] Figure 4 This is a schematic diagram of the Z-axis lifting mechanism in a specific embodiment of this utility model;

[0035] Figure 5 This is a schematic diagram of the stepper module in a specific embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of the scanning module in a specific embodiment of the present invention;

[0037] Figure 7 A schematic diagram of a projected image of a DMD chip without a set tilt scanning angle;

[0038] Figure 8 A schematic diagram of a projection graphic for setting the tilt scan angle of a DMD chip;

[0039] Figure 9 A schematic diagram of the imaging on the printed surface when setting the tilt scanning angle of the DMD chip. Detailed Implementation

[0040] For the convenience of understanding the present application, the present application will be described more fully below with reference to the specific embodiments. The preferred embodiments of the present application are given in the specific embodiments. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0041] The words "optionally" and the like in the present application refer to the embodiments of the present application which can provide certain beneficial effects in certain cases. However, other embodiments can also be optional in the same or other cases. In addition, the description of one or more optional embodiments does not imply that other embodiments are not available, nor is it intended to exclude other embodiments from the scope of the present application.

[0042] Figures 1 to 9 As shown, the present application provides a 3D printing system based on DLP technology, which comprises a trough module 1 and a projection assembly 2 located on the upper side of the trough module 1. The trough module 1 comprises a resin tank 11 for containing liquid photosensitive resin, and a tray 12 for carrying the formed parts. The liquid photosensitive resin can be selected from the commonly used photosensitive resin in the field of 3D printing, such as epoxy resin, acrylate, etc. The material of the liquid photosensitive resin is selected according to the actual printed object. The size of the resin tank 11 is determined according to the amount of photosensitive resin, the size of the tray 12, and the projection position of the projection assembly 2.

[0043] In the process of 3D printing, the tray 12 is immersed in the photosensitive resin carried by the resin tank 11, and a printing surface is formed on the surface of the tray 12 or the surface of the formed parts carried by the tray 12. The projection assembly 2 is used to project the image of each slice to the printing surface, and the corresponding layer of photosensitive resin of the printing surface is photo-cured to form. The projection assembly 2 comprises a light source, a DMD chip 21 and an optical lens. Specifically, the light source can be selected from a semiconductor laser light source or an ultraviolet LED light source. The light emitted by the light source is adjusted by the light path inside the projection assembly 2, so that the semiconductor laser light source or the ultraviolet LED light source is irradiated onto the DMD chip 21. The DMD chip 21 is composed of many small aluminum reflecting mirrors (referred to as micro-mirrors), and the opening and closing states of the micro-mirrors are controlled by controlling the rotation of the micro-mirrors around the fixed yoke, so as to control the projection pattern of the DMD chip 21. The projection pattern generated by the DMD chip 21 is imaged on the corresponding position of the printing surface through the optical lens.

[0044] The 3D printing system further comprises a motion control assembly, and an industrial control module electrically connected with the motion control assembly and the projection assembly 2. Specifically, the motion control assembly comprises a Z-axis lifting mechanism 3 for driving the tray 12 to move along the z direction, and an XY plane motion mechanism for controlling the coordinate position of the projection assembly 2 in the printing surface. The XY plane motion mechanism precisely controls the coordinate position of the projection assembly 2 in the printing surface, realizes dynamic projection of the projection assembly 2, and enables the 3D printing system to meet large-size processing and improve the processing efficiency of the 3D printing system. The industrial control module controls the Z-axis lifting mechanism 3 to drive the tray 12 to move along the z direction according to the molding data information, and controls the coordinate position of the projection assembly 2 in the printing surface through the XY plane motion mechanism, so that the image projected by the projection assembly 2, the position of the projection assembly 2 and the height of the tray 12 are matched, and the 3D printing system realizes layer-by-layer printing and curing of the photosensitive resin to obtain a high-precision 3D molded part.

[0045] In one embodiment, the XY plane motion mechanism comprises a stepping module 4 for driving the projection assembly 2 to move along the x direction, and a scanning module 5 for driving the projection assembly 2 to move along the y direction. In this embodiment, the directions of x, y and z are shown in the figure. Figure 1 As shown in the figure, the height of the tray 12 is precisely adjusted through the Z-axis lifting mechanism 3, and the position of the projection assembly 2 is precisely controlled through the stepping module 4 and the scanning module 5, so that the x direction and y direction positions of the projection assembly 2 are adjusted, and dynamic projection of the projection assembly 2 is realized. This enables the 3D printing system to meet large-size processing and improve the processing efficiency of the 3D printing system.

[0046] In one embodiment of the utility model, the control principle diagram of the 3D printing system is shown in the figure. Figure 3 As shown in the figure, the industrial control module is a software implementation platform of the 3D printing system, and is responsible for controlling power-on, process, detection and the like. Specifically, the scanning module 5 controls the projection assembly 2 to perform scanning printing along the y direction according to a certain stepping width. The projection assembly 2 is considered to complete the image of one strip when it prints all the images of the corresponding position along the y direction from the initial printing position, then the stepping module 4 drives the projection assembly 2 to move along the x direction by one stepping width, so that the projection assembly 2 performs image processing of the next strip. The industrial control module controls the Z-axis lifting mechanism 3, the stepping module 4 and the scanning module 5 in linkage, controls the stepping module 4 and the scanning module 5 to cooperate with each other to perform strip-by-strip scanning exposure according to the data information between the strips, and simultaneously controls the Z-axis lifting mechanism 3 to drive the tray 12 to move along the z direction according to the molding data information, so that the imaging of the projection assembly 2, the position of the projection assembly 2 and the height of the tray 12 are matched, and the 3D printing system realizes layer-by-layer printing and curing of the photosensitive resin to obtain a high-precision 3D printing molded part.

[0047] Further, the projection assembly 2 further comprises a DMD driving module for controlling the projection imaging of the DMD chip 21, the DMD driving module is electrically connected with the industrial control module, the DMD driving module regulates and controls the projection pattern of the DMD chip 21, ensures that the imaging of the DMD chip 21 matches the height of the projection assembly 2 and the tray 12, and realizes layer-by-layer printing and curing of the photosensitive resin to obtain a high-precision formed part.

[0048] In one specific embodiment of the present application, the Z-axis lifting mechanism 3 comprises a lifting control module, a lifting driving module, a lifting motor 31 and a lifting transmission module 32. Specifically, the lifting control module is used for receiving signals of the industrial control module, the lifting driving module is used for receiving signals of the lifting control module, the lifting motor 31 is used for receiving driving signals of the lifting driving module, and the lifting transmission module 32 is driven by the lifting motor 31 to drive the tray 12 to move along the Z-axis, thereby accurately controlling the height of the tray 12.

[0049] Preferably, the lifting transmission module 32 comprises a lead screw 321 connected with the output end of the lifting motor 31, a screw block matched with the lead screw 321, a support plate 322 connected with the screw block, and a support frame 323 connected with the support plate 322, and the tray 12 is fixed to one side of the support frame 323 close to the resin tank 11. Since the lead screw 321 is connected with the output end of the lifting motor 31, the lifting motor 31 drives the lead screw 321 to rotate after being turned on, the screw block moves up and down along the lead screw 321, and the support plate 322 and the support frame 323 drive the tray 12 to move up and down synchronously with the screw block, thereby accurately adjusting the height of the tray 12.

[0050] Further, the 3D printing system further comprises a position synchronization module electrically connected with the industrial control module, the position synchronization module is used for receiving position information of the scanning module 5 and transmitting a position synchronization signal to the DMD driving module, so that the DMD driving module regulates and controls the projection pattern of the DMD chip 21, ensures that the projection pattern of the DMD chip 21 matches the scanning position of the projection assembly 2, and realizes layer-by-layer printing and curing of the photosensitive resin to obtain a high-precision formed part.

[0051] Further, the stepping module and the scanning module each comprise a guide rail, a first control module, a first driving module, a first motor and a first transmission module, specifically, the guide rails of the stepping module and the scanning module are perpendicular to each other, the first control module is used for receiving signals of the industrial control module, the first driving module is used for receiving signals of the first control module, the first motor is used for receiving driving signals of the first driving module, and the first transmission module is driven by the first motor to drive the projection assembly 2 to slide along the stepping guide rail or the scanning guide rail.

[0052] In one specific embodiment, as shown in Figure 5As shown in the drawings, the stepping module 4 comprises a stepping guide rail 41, a stepping control module, a stepping drive module, a stepping motor and a stepping transmission module. Specifically, the stepping guide rail 41 extends along the x direction, the stepping control module is configured to receive signals from the industrial control module, the stepping drive module is configured to receive signals from the stepping control module, the stepping motor is configured to receive driving signals from the stepping drive module, the stepping motor drives the stepping transmission module, and the stepping transmission module drives the projection assembly 2 to slide along the stepping guide rail, thereby precisely adjusting the position of the projection assembly 2 in the x direction.

[0053] Further, as shown in the drawings, Figure 6 The scanning module 5 comprises a scanning guide rail 51, a scanning control module, a scanning drive module, a scanning motor and a scanning transmission module. Specifically, the scanning guide rail 51 extends along the y direction, the scanning control module is configured to receive signals from the industrial control module, the scanning drive module is configured to receive signals from the scanning control module, the scanning motor is configured to receive driving signals from the scanning drive module, and the scanning transmission module is driven by the scanning motor to move, thereby driving the projection assembly 2 to slide along the scanning guide rail, thereby precisely adjusting the position of the projection assembly 2 in the y direction.

[0054] Specifically, the scanning guide rail 51 comprises a first scanning guide rail 511 and a second scanning guide rail 512 arranged opposite to each other along the x direction, and the stepping guide rail is slidingly connected to the first scanning guide rail 511 and the second scanning guide rail 512 at both ends, and the projection assembly 2 is slidingly connected to the stepping guide rail. The projection assembly 2 of the 3D printing system of the present application adopts an inclined scanning technology. After the projection assembly 2 is installed on the stepping guide rail, the DMD chip 21 forms an inclined scanning angle θ with the stepping guide rail, so that the 3D printing system of the present application has higher forming precision

[0055] As shown in the drawings, Figure 7 and 8 As shown in the drawings, Figure 7 is an imaging pattern diagram of the DMD chip 21 without setting an inclined scanning angle, Figure 8 is an imaging pattern diagram of the DMD chip 21 with setting an inclined scanning angle. One small square in the diagram represents one micromirror, one micromirror represents one pixel, and the DMD chip 21 is composed of many micromirrors. In order to clearly show the relationship between the number of opened micromirrors and the width of the image, the present application uses different colors for display. The micromirrors filled with color represent the opened micromirrors, and the white micromirrors represent the closed micromirrors. Moreover, the micromirrors are consistent in color with the corresponding projection pattern 22. As can be seen from Figure 7 In the case where the DMD chip 21 is not set with an inclined scanning angle, each increase of one micromirror opened in the width direction, i.e. each increase of one pixel of the DMD chip 21, doubles the width of the projection pattern 22 of the DMD chip, and it is impossible to realize the gradual transition between the image width of one DMD micromirror and the image width of two DMD micromirrors.Figure 8 As can be seen, in the case that the DMD chip 21 is provided with the inclined scanning angle θ, the width w of the projection pattern 22 is gradually transitioned with each increase of the opened DMD micromirror, that is, each increase of the pixel of the DMD chip 21, so that the projection assembly 2 with the inclined scanning angle of the DMD chip 21 has higher imaging pattern precision, and the projection assembly 2 adopting the inclined scanning technology makes the 3D printing system of the utility model have higher forming precision.

[0056] Further, in actual application, the inclined scanning angle θ of the DMD chip 21, the subdivision number m of the DMD chip 21 and the optical lens magnification n can be freely matched according to the required precision and scanning size, so that the projection assembly 2 can also meet the precision while ensuring the efficiency. Specifically, the following formula (1) and formula (2) can be used for calculation:

[0057] pw = m * p * sin θ (1)

[0058] θ=arctan(1 / m) (2)

[0059] In the formula (1) and formula (2), pw is the forming precision, m is the subdivision number of the DMD chip 21, p is the pixel size of the DMD chip 21, that is, the size of each micromirror, and θ is the inclined scanning angle of the DMD chip 21.

[0060] Referring to Figure 9 the imaging pattern of the projection pattern generated by the DMD chip 21 on the printing surface through the optical lens is shown, wherein the DMD chip 21 is provided with the inclined scanning angle θ, and the imaging size of the printing surface is calculated according to the following formula (3) and formula (4):

[0061] w = n * p * N * cos θ (3)

[0062] h = n * p * M * cos θ (4)

[0063] In the formula (3) and formula (4), w is the width of the imaging pattern 23, h is the length of the imaging pattern 23, the imaging pattern 23 refers to the pattern formed by the projection pattern of the DMD chip 31 on the printing surface through the optical lens magnification, n is the optical lens magnification, p is the pixel size of the DMD chip 21, N is the number of DMD long side pixels, M is the number of DMD short side pixels, and θ is the inclined scanning angle of the DMD chip 21.

[0064] The 3D printing system XY plane movement mechanism accurately controls the coordinate position of the projection assembly 2 on the printing surface, realizes dynamic projection of the projection assembly 2, and makes the 3D printing system capable of meeting large-size processing and improving the processing efficiency of the 3D printing system. According to the molding data information, the industrial control module controls the Z-axis lifting mechanism 3 to drive the tray 12 to move in the z direction, and the XY plane movement mechanism controls the coordinate position of the projection assembly 2 on the printing surface, so that the pattern projected by the projection assembly 2, the position of the projection assembly 2 and the height of the tray 12 are matched, layer-by-layer printing and curing of photosensitive resin of the 3D printing system are realized, and high-precision 3D molded parts are obtained.

[0065] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A 3D printing system based on DLP technology, characterized in that, The 3D printing system comprises: a material tank module comprising a resin tank for containing liquid photosensitive resin and a tray for carrying a molding piece; a projection assembly arranged on the upper side of the material tank module, comprising a light source, a DMD chip and an optical lens; a motion control assembly comprising: a Z-axis lifting mechanism for driving the tray to move in the vertical direction; an XY plane motion mechanism for controlling the coordinate position of the projection assembly in the printing plane; an industrial control module electrically connected to the motion control assembly and the projection assembly; the projection assembly comprises a DMD drive module for controlling the projection imaging of the DMD chip; the XY plane motion mechanism comprises a scanning module for driving the projection assembly to move in the y direction; the 3D printing system further comprises a position synchronization module electrically connected to the industrial control module, the position synchronization module is used for receiving the position information of the scanning module and transmitting a position synchronization signal to the DMD drive module.

2. The DLP technology-based 3D printing system of claim 1, wherein, The DMD drive module is electrically connected to the industrial control module.

3. The DLP technology-based 3D printing system of claim 2, wherein, The XY plane motion mechanism comprises a stepping module for driving the projection assembly to move in the x direction.

4. The DLP technology-based 3D printing system of claim 3, wherein, The stepping module and the scanning module both comprise: a guide rail, the guide rail of the stepping module and the guide rail of the scanning module are perpendicular to each other; a first control module for receiving signals from the industrial control module; a first drive module for receiving signals from the first control module; a first motor for receiving driving signals from the first drive module; a first transmission module driven by the first motor, for sliding the projection assembly along the guide rail.

5. The DLP technology-based 3D printing system of claim 4, wherein, The stepping module comprises a stepping guide rail extending in the x direction, and the scanning module comprises a first scanning guide rail and a second scanning guide rail extending in the y direction and arranged oppositely; the two ends of the stepping guide rail are respectively slidingly connected to the first scanning guide rail and the second scanning guide rail, and the projection assembly is slidingly connected to the stepping guide rail.

6. The DLP technology-based 3D printing system of claim 5, wherein, After the projection assembly is installed on the stepping guide rail, the DMD chip forms an inclined scanning angle θ with the stepping guide rail.

7. The DLP technology-based 3D printing system of claim 1, wherein, The Z-axis lifting mechanism comprises: a lifting control module for receiving signals from the industrial control module; a lifting drive module for receiving signals from the lifting control module; a lifting motor for receiving driving signals from the lifting drive module; a lifting transmission module driven by the lifting motor and driving the tray to move along the Z-axis.

8. The DLP technology-based 3D printing system of claim 7, wherein, The lifting transmission module comprises a lead screw connected to the output end of the lifting motor, a screw block matched with the lead screw, a support plate connected to the screw block, and a support frame connected to the support plate, and the tray is fixed to one side of the support frame close to the resin tank.

9. The DLP technology-based 3D printing system of claim 2, wherein, The light source comprises a semiconductor laser light source or an ultraviolet LED light source.

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