A 3D printer for improving model accuracy

Abstract

This invention discloses a 3D printer for improving model accuracy, including a base plate with a window for light to enter. A first mounting position around the window is used to mount an LCD screen. An annular boss is located outside the first mounting position. A second mounting position outside the boss can be detachably mounted with a pressure ring, which locks the LCD screen in the first mounting position for quick assembly and disassembly. A fourth mounting position outside the second mounting position mounts a resin tank with a release film. The upper surface of the LCD screen is higher than the mounting plane of the fourth mounting position, which can lift the release film upward to tighten it, thereby improving printing accuracy.

Description

[0001] This application is a divisional application of CN202211334744.8; The original application was filed on October 28, 2022; The original application number was CN202211334744.8; The original invention application was titled "A mechanical structure for quick LCD screen replacement and a 3D printer". Technical Field

[0002] This invention relates to the field of 3D printing, and more particularly to a 3D printer that improves model accuracy. Background Technology

[0003] LCD printing is a relatively new 3D printing technology. A light source shines from bottom to top through an LCD screen to form a pattern, which is then projected onto the resin between the molding substrate and the bottom of the resin tank, causing the resin to solidify on the molding substrate. The molding substrate is immersed in the resin, which is stored in the resin tank, which is placed on the LCD screen. A transparent, flexible release film on the bottom of the resin tank is attached to the upper surface of the LCD screen. After printing multiple layers, the final product is obtained. After each layer is printed, the molding substrate needs to be raised and lowered to allow the resin to flow back, and the LCD screen will switch to display the pattern of the next layer.

[0004] Specifically, during operation, resin is poured into the resin tank, with the release film positioned below the resin. The printing platform, driven by the printer's lifting module, immerses the molding substrate in the resin, displaying a single-layer image of the model on the LCD screen. Light source illumination causes the resin to solidify with this image. When the release film is flat and adheres to the LCD screen, the printed model is more accurate. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a 3D printer for improving model accuracy, comprising a base plate with a window for light to enter, and a first mounting position around the window for mounting an LCD screen; an annular boss on the outer side of the first mounting position, and a second mounting position on the outer side of the boss for detachably mounting a pressure ring, which locks the LCD screen in the first mounting position for quick assembly and disassembly; and a fourth mounting position on the outer side of the second mounting position for mounting a resin tank with a release film, wherein the upper surface of the LCD screen is higher than the mounting plane of the fourth mounting position, which can lift the release film upward to tighten it, thereby improving printing accuracy.

[0006] The technical solution of this invention is implemented as follows: A 3D printer for improving model accuracy includes a base plate with a window for light to enter. A first mounting position is provided around the window, and an LCD screen is mounted in the first mounting position. An annular boss is provided outside the first mounting position, and a second mounting position is provided outside the boss. A pressure ring is detachably mounted on the second mounting position, configured to lock the LCD screen in the first mounting position. A fourth mounting position is provided outside the second mounting position, and a resin tank is mounted on the fourth mounting position. A release film is located at the bottom of the resin tank. The upper surface of the LCD screen is higher than the mounting plane of the fourth mounting position and is configured to lift the release film at the bottom of the resin tank upwards to tighten the release film.

[0007] In this solution, by setting the upper surface of the LCD screen to a mounting plane higher than the fourth mounting position, the LCD screen can lift the release film at the bottom of the resin tank after the resin tank is installed, thereby keeping the release film in a taut state and improving printing accuracy.

[0008] In this solution, a removable pressure ring is also provided at the second mounting position to lock the LCD screen in the first mounting position, thereby enabling quick installation and removal of the LCD screen.

[0009] As a preferred option: A third mounting position is provided between the window and the first mounting position, and a Fresnel lens is installed in the third mounting position.

[0010] Fresnel lenses are used to recalibrate the scattered light path emitted by a light source into direct light.

[0011] As a preferred option: The pressure ring includes an outer ring portion and an inner ring portion; The outer ring is located in the second mounting position, and the outer ring is configured to be detachably mounted to the second mounting position; When the pressure ring is in the installation state, the inner ring portion is above the boss, and the other portion of the inner ring is in the first installation position; The boss is configured to prevent resin from entering the first mounting position.

[0012] The inner and outer rings of the pressure ring have distinct functions. The outer ring is used for detachable connection with the base plate, while the inner ring extends inward into the first mounting position to lock the LCD screen in the first mounting position. The boss can block the resin outside the first mounting position to prevent the resin from continuing to leak downward and affecting the printer.

[0013] As a preferred option: The inner ring protrudes upwards from the upper surface of the outer ring, and the inner ring of the LCD screen and the pressure ring protrudes upwards from the fourth mounting position.

[0014] As a preferred option: The inner ring is thinned to form a locking position, part of which rests on the upper surface of the boss, and the other part of the locking position is configured to press the LCD screen into the first mounting position.

[0015] The shape of the pressure ring is not a simple flat plate, but has certain height variations and bends, similar to a step. The inner ring is on a higher horizontal plane than the outer ring, so as to lock the LCD screen over the protrusion. Specifically, the pressure ring locks the LCD screen from top to bottom through the locking position formed by the inner ring, preventing the LCD screen from being loosened by upward force, thus solving the problem of LCD screen locking.

[0016] As a preferred option: The liquid crystal screen includes an LCD screen and a glass backing plate; An LCD screen, located above a glass pad, is configured to image 3D printing. The upper surface of the glass pad is higher than or equal to the upper surface of the boss. The glass pad includes: The support is located in the vertical projection area of ​​the LCD screen (21) and is configured to support the LCD screen; The locking part is located on the outer periphery of the vertical projection area of ​​the LCD screen and is configured to be at least partially pressed by the locking position of the pressure ring.

[0017] The LCD screen needs to function, so it is more reasonable for the pressure ring to press against the glass pad; the locking part can be partially or completely locked by the pressure ring.

[0018] As a preferred option: The height of the upper surface of the inner ring of the pressure ring shall not exceed the height of the upper surface of the LCD screen.

[0019] As the base surface for 3D printing, the LCD screen needs to be in direct contact with the resin tank. If it is lower than the height of the inner ring of the pressure ring, it will be suspended from the bottom of the resin tank, which will seriously affect the printing effect. Therefore, it is necessary for the upper surface of the LCD screen to be higher than the upper surface of the pressure ring so that the release film at the bottom of the resin tank can better adhere to the LCD screen.

[0020] As a preferred option: The pressure ring is a ring frame; The lower surface of the pressure ring is also provided with an annular light-shielding film, which is at least partially configured to be installed on the edge of the upper surface of the LCD screen.

[0021] The light-blocking film blocks light that may be refracted / scattered from the edge of the LCD screen. This unexpected light may change the light intensity in some areas, causing overexposure in some parts of the 3D model surface, resulting in a rough surface and texture on the 3D printed model. In addition, this unexpected light may cause the resin to cure unexpectedly, thus producing debris. If the debris is suspended in the resin, it may lead to printing failure, damage to the release film, and other problems.

[0022] As a preferred option: After the LCD screen is placed in the first mounting position, the LCD screen is in contact with the inner side of the boss, and the upper surface of the LCD screen is higher than the upper surface of the boss.

[0023] Because the inner ring of the pressure ring is thinned upwards and there is a locking position, if the upper surface of the LCD screen is lower than the upper surface of the protrusion, the pressure ring cannot lock the LCD screen, and the LCD screen may still move inside, which will have an adverse effect on the printing work.

[0024] The design starting point, concept, and beneficial effects of the present invention, which adopts the above technical solution, are as follows: In this solution, by setting the upper surface of the LCD screen to a mounting plane higher than the fourth mounting position, the LCD screen can lift the release film at the bottom of the resin tank after the resin tank is installed, thereby keeping the release film in a taut state and improving printing accuracy.

[0025] In this solution, a removable pressure ring is also provided at the second mounting position to lock the LCD screen in the first mounting position, thereby enabling quick installation and removal of the LCD screen. Attached Figure Description

[0026] Figure 1 This is an exploded view of the mechanical structure in an embodiment of the present invention; Figure 2 This is a three-dimensional structural diagram of the LCD 3D printer in an embodiment of the present invention; Figure 3 This is a three-dimensional structural diagram of the base plate in an embodiment of the present invention; Figure 4 This is a schematic diagram of the three-dimensional structure of the pressure ring in an embodiment of the present invention. Figure 1 ; Figure 5 This is a schematic diagram of the three-dimensional structure of the pressure ring in an embodiment of the present invention. Figure 2 ; Figure 6 This is a three-dimensional structural diagram of the mechanical structure after assembly in an embodiment of the present invention; Figure 7 This is a cross-sectional view of the mechanical structure in an embodiment of the present invention; Figure 8 for Figure 7 A magnified view of a portion of the image; Figure 9 This is a three-dimensional structural diagram of the glass pad in an embodiment of the present invention.

[0027] The reference numerals in the attached drawings are as follows: base plate 1; LCD screen 2; LCD screen 21; glass pad 22; support part 221; locking part 222; pressure ring 3; outer ring part 31; inner ring part 32; locking position 33; window 4; mounting part 5; first mounting position 51; second mounting position 52; third mounting position 53; fourth mounting position 54; boss 6; frame 7; exposure mechanism 8; resin tank 9; molding substrate 10; printing platform 11; lifting module 12; light shielding film 13; Fresnel lens 14; fixing plate 15; countersunk screw 16; ribbon cable 17; ribbon cable hole 18; hook 19. Detailed Implementation

[0028] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0030] In the description of this invention, the term "at least one" means one or more, unless otherwise expressly defined. The terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] The specific embodiments of the present invention are as follows: like Figure 1 , 6 As shown, the present invention provides a mechanical structure for quickly replacing an LCD screen, including a base plate 1, an LCD screen 2, and a pressure ring 3. The base plate 1 is configured as the main support of the mechanical structure. A window 4 for light to enter is provided on the base plate 1. A first mounting position 51 for mounting the LCD screen 2 is provided around the window 4. An annular boss 6 is provided on the outer side of the first mounting position 51. A second mounting position 52 for mounting the pressure ring 3 is also provided on the outer side of the boss 6. The LCD screen 2 is placed on the first mounting position 51 of the base plate 1. The pressure ring 3 is fixedly mounted on the second mounting position 52 of the base plate 1 by screws and passes over the boss 6 to lock the LCD screen 2 in the first mounting position 51. The boss 6 is configured to prevent resin from entering the machine.

[0032] In this design, the LCD screen 2 is no longer fixed to the base plate 1 using adhesive or other means. Instead, it is detachably connected via a mechanical installation method using a locking ring 3. After the LCD screen 2 ages, the locking ring 3 can be directly removed, and the LCD screen 2 can be taken out from the first mounting position 51 for easy replacement. This makes the replacement and disassembly of the LCD screen 2 convenient, eliminating the need to clean residual adhesive and simplifying the replacement process without requiring professional personnel. Furthermore, the locking ring 3 locks the LCD screen 2 from top to bottom, ensuring that the LCD screen 2 will not loosen even under vacuum adsorption generated by the release film, thus maintaining good operational stability. Additionally, the resin in the resin tank 9 poses a risk of leakage. There is a possibility that resin material may leak from the resin tank 9 due to damage to the release film or improper operation. In this case, disassembling the LCD screen 2 will cause the leaked resin to flow along the base plate 1 into the window 4 and then drip into the machine. The boss 6 is located between the first mounting position 51 and the second mounting position 52. Even if the resin accidentally seeps into the mechanical structure, the boss 6 can block the resin outside the first mounting position 51 to prevent the resin from continuing to seep downward and affecting the printer. At the same time, the boss 6 can also provide installation limits for the LCD screen 2 and the pressure ring 3, making it easier to install both. Therefore, disassembling and assembling the LCD screen 2 is more convenient, faster and easier to operate.

[0033] Specifically, such as Figure 1 , 2 As shown, this mechanical structure is used in an LCD 3D printer. These printers typically use a downward-facing light source arrangement. It includes a frame 7, an exposure mechanism 8 (i.e., the light source), a resin tank 9, a printing platform 11, a lifting module 12, and the aforementioned mechanical structure. The frame 7 serves as the main support for the printer, used to mount other components. The exposure mechanism 8 is the light source in the 3D printer, mounted on the lower part of the frame 7 and capable of emitting light upwards. The lifting module 12 is vertically positioned with the printing platform 11 mounted on it. The printing platform 11 includes a molding substrate 10 located below it. The lifting module 12 drives the printing platform 11 and the molding substrate 10 to rise and fall, forming the model on the molding substrate 10. The resin tank 9 is placed on the mechanical structure, and resin material is poured into the resin tank 9. The mechanical structure is mounted on the frame 7 and is located above the exposure mechanism 8 and below the molding substrate 10.

[0034] The mechanical structure also includes a light-shielding film 13, a Fresnel lens 14, and a fixing plate 15; such as Figure 3As shown, the base plate 1 has a stepped mounting portion 5 around the window 4. The first mounting position 51 and the second mounting position 52 are both located within the mounting portion 5. The mounting portion 5 also includes a third mounting position 53 and a fourth mounting position 54. The third mounting position 53 is located between the first mounting position 51 and the window 4 and is configured to mount the Fresnel lens 14. The fourth mounting position 54 is located outside the third mounting position 53 and is configured to mount the resin tank 9. A stepped rise is formed between the third mounting position 53 and the first mounting position 51, and the first step is configured to limit the Fresnel lens 14. A stepped rise is also formed between the second mounting position 52 and the fourth mounting position 54, and the second step limits the resin tank 9. The height of the upper surface of the third mounting position 53 is lower than that of the upper surface of the first mounting position 51, and the height of the upper surface of the second mounting position 52 is lower than that of the upper surface of the fourth mounting position 54. The boss 6 is located between the first mounting position 51 and the second mounting position 52, and the height of the upper surface of the second mounting position 52 is higher than that of the upper surface of the first mounting position 51. Therefore, in the mounting part 5, from bottom to top and from inside to outside, the third mounting position 53, the first mounting position 51, the second mounting position 52 and the fourth mounting position 54 are installed in sequence, and the Fresnel lens 14 (at the third mounting position 53), the liquid crystal screen 2 (at the first mounting position 51), the pressure ring 3 (at the second mounting position 52) and the resin tank 9 (at the fourth mounting position 54) are installed in sequence.

[0035] like Figure 4 , 5 As shown, the pressure ring 3 is an annular frame, including an outer ring 31 and an inner ring 32. The outer ring 31 is located in the second mounting position 52 and is detachably connected to the second mounting position 52. The inner ring 32 protrudes upward from the upper surface of the outer ring 31 and the lower surface of the inner ring 32 is thinned upward to form a locking position 33. The LCD screen 2 is located between the first mounting position 51 and the locking position 33. The inner ring 32 is located above the boss 6 and the edge of the LCD screen 2, and the inner ring 32 presses the LCD screen 2 tightly in the first mounting position 51. The middle of the pressure ring 3 is hollowed out to allow rays to pass through. The outer ring 31 and the inner ring 32 of the edge frame can be used to install themselves and lock the LCD screen 2. The shape of the pressure ring 3 is not a simple flat plate, but has certain height changes and bends, similar to a step. The horizontal plane of the inner ring 32 is higher than that of the outer ring 31, so as to pass over the boss 6 to lock the LCD screen 2.

[0036] like Figure 7As shown, an annular light-shielding film 13 is provided below the pressure ring 3. The light-shielding film 13 is pasted on the edge of the LCD screen 2 and locked to the base plate 1 together with the pressure ring 3 by screws. The screws are countersunk screws. The light-shielding film 13 is used to block the light that may be exposed at the edge of the LCD screen 2, which can make the model more accurate. The use of countersunk screws 16 can make the upper surface of the pressure ring 3 as flat as possible. After the LCD screen 2 is placed in the first mounting position 51, it is close to the side of the boss 6 and the LCD screen 2 is higher than the boss 6. The light-shielding film 13 is flexible. After it is deformed, it can fit the surface of the LCD screen 2, the boss 6 and the second mounting position 52.

[0037] like Figure 8 , 9 As shown, the LCD screen 2 and the pressure ring 3 protrude upwards from the fourth mounting position 54; the upward protrusion of the LCD screen 2 and the pressure ring 3 from the fourth mounting position 54 can lift the flexible release film (not shown) at the bottom of the resin tank 9, thereby tightening it, which is beneficial to improve the model accuracy. Moreover, the height of the upper surface of the inner ring of the pressure ring does not exceed the height of the upper surface of the LCD screen, which allows the release film at the bottom of the resin tank to better adhere to the LCD screen; the LCD screen 2 includes an LCD screen 21 and a glass pad 22, the glass pad 22 is located below the LCD screen 21 and the edge of the glass pad 22 protrudes from the LCD screen. The edge of the screen 21 and the edge of the glass pad 22 protrude 3-5mm beyond the edge of the LCD screen 21, which is 4mm in this embodiment; that is, the glass pad 22 includes a support part 221 and a locking part 222. The support part 221 is located in the vertical projection area of ​​the LCD screen 21 and is configured to support the LCD screen 21. The locking part 222 is located on the outer periphery of the vertical projection area of ​​the LCD screen and is configured to be at least partially pressed by the locking position 33 of the pressure ring 3. When locking the LCD screen 2, the pressure ring 3 is pressed on the glass pad 22, which will not affect the LCD screen 21 and its operation, which is more reasonable.

[0038] In addition, such as Figure 1 , 7 As shown, the fixing plate 15 is installed below the base plate 1 by screws; the LCD screen 2 includes a ribbon cable 17 for electrical connection, and the boss 6 is provided with a ribbon cable hole 18 that runs vertically through it. The ribbon cable 17 passes through the ribbon cable hole 18 and is inserted into the fixing plate 15; the fixing plate 15 is provided with two hooks 19 for inserting the ribbon cable 17, one on the left and one on the right, which are fixed to the fixing plate 15 respectively, and the ribbon cable 17 is inserted into the hooks 19; in this solution, the original horizontal arrangement of the ribbon cable 17 is changed to a vertical arrangement, so that the LCD screen 2 is pressed by the pressure ring 3 without affecting the ribbon cable 17, and the structure is more reasonable.

[0039] During installation, first install the mounting plate 15 onto the base plate 1 from bottom to top using screws. Then, place the Fresnel lens 14 from top to bottom in the third mounting position 53. Next, place the LCD screen 2 from top to bottom into the first mounting position 51. Insert the ribbon cable 17 of the LCD screen 2 into the hook 19 of the mounting plate 15 through the ribbon cable hole 18. Connect the data cable to the corresponding interface of the ribbon cable 17. Then, stick the light-shielding film 13 to the edge of the LCD screen 2. Install the pressure ring 3 from top to bottom into the second mounting position 52. Finally, secure and lock it with countersunk screws 16.

[0040] When replacing the LCD screen 2, simply remove the retaining ring 3, peel off the light-blocking film 13, lift the LCD screen 2 upwards appropriately, and the ribbon cable 17 will disengage from the hook 19. After unplugging the data cable, the LCD screen disassembly is complete. The process is simple and easy to operate.

Claims

1. A 3D printer for improving model accuracy, characterized in that: The device includes a base plate with a window for light to enter. A first mounting position is provided around the window, and an LCD screen is mounted in the first mounting position. An annular boss is provided outside the first mounting position, and a second mounting position is provided outside the boss. A pressure ring is detachably mounted on the second mounting position, and the pressure ring is configured to lock the LCD screen in the first mounting position. A fourth mounting position is provided outside the second mounting position, and a resin tank is mounted on the fourth mounting position. The bottom of the resin tank has a release film. The upper surface of the LCD screen is higher than the mounting plane of the fourth mounting position and is configured to lift the release film at the bottom of the resin tank upward to make the release film taut. The pressure ring includes an outer ring portion and an inner ring portion; the outer ring portion is located in a second mounting position and is configured to be detachably installed with the second mounting position; when the pressure ring is in the installed state, part of the inner ring portion is above the boss, and the other part of the inner ring portion is in the first mounting position; the boss is configured to prevent resin from entering the first mounting position.

2. The 3D printer for improving model accuracy according to claim 1, characterized in that: A third mounting position is provided between the window and the first mounting position, and a Fresnel lens is installed in the third mounting position.

3. The 3D printer for improving model accuracy according to claim 1, characterized in that: The inner ring protrudes upwards from the upper surface of the outer ring, and the inner ring of the LCD screen and the pressure ring protrudes upwards from the fourth mounting position.

4. The 3D printer for improving model accuracy according to claim 3, characterized in that, Also includes: The inner ring is thinned to form a locking position, part of which rests on the upper surface of the boss, and the other part of the locking position is configured to press the LCD screen into the first mounting position.

5. The 3D printer for improving model accuracy according to claim 4, characterized in that: The liquid crystal screen includes an LCD screen and a glass backing plate; An LCD screen, located above a glass pad, is configured to image 3D printing. The upper surface of the glass pad is higher than or equal to the upper surface of the boss. The glass pad includes: A support unit, located within the vertical projection area of ​​the LCD screen, is configured to support the LCD screen. The locking part is located on the outer periphery of the vertical projection area of ​​the LCD screen and is configured to be at least partially pressed by the locking position of the pressure ring.

6. The 3D printer for improving model accuracy according to claim 5, characterized in that: The height of the upper surface of the inner ring of the pressure ring shall not exceed the height of the upper surface of the LCD screen.

7. The 3D printer for improving model accuracy according to claim 1, characterized in that: The pressure ring is an annular frame; the lower surface of the pressure ring is also provided with an annular light-shielding film, and the light-shielding film is at least partially configured to be installed on the edge of the upper surface of the LCD screen.

8. The 3D printer for improving model accuracy according to claim 1, characterized in that: After the LCD screen is placed in the first mounting position, the LCD screen is in contact with the inner side of the boss, and the upper surface of the LCD screen is higher than the upper surface of the boss.

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