Composite film, 3D printing cartridge and 3D printing device

Abstract

The application provides a composite film, a 3D printing cartridge and a 3D printing device, and relates to the field of additive manufacturing. The composite film comprises a composite film body, the composite film body comprises a first thermoplastic film and a second thermoplastic film which are stacked, the first thermoplastic film and the second thermoplastic film are fixedly connected through ultrasonic welding, and a welding site is formed in the welded area; a printing area is arranged in the middle of the composite film body, and the welding site is located at the periphery of the printing area. The composite film provided by the application solves the technical problems of transparent resin atomization, yellowing or darkening caused by the light transmission characteristics of the light-transmitting centrifugal film in the prior art.

Description

Technical Field

[0001] This application relates to the field of additive manufacturing, and more specifically, to a composite film, a 3D printing cartridge, and a 3D printing device. Background Technology

[0002] Photopolymer 3D printing technology primarily uses liquid resin as raw material. It utilizes the property of liquid resin to cure under light of a specific wavelength and intensity (usually ultraviolet light) to complete the printing process. Photopolymer 3D printer equipment generally includes a cartridge, which is a cavity with openings at both ends. One of the openings is covered with a light-transmitting release film, through which light passes to irradiate the liquid resin.

[0003] In the existing technology, the release film itself does not have the function of uniform light distribution. Its light transmission characteristics will indirectly affect the uniformity of light, resulting in phenomena such as fogging, yellowing, and darkening of transparent resin. Utility Model Content

[0004] The purpose of this application is to provide a composite film, a 3D printing cartridge, and a 3D printing device to alleviate the technical problems of transparent resin fogging, yellowing, and darkening caused by the light-transmitting characteristics of light-transmitting release films in the prior art.

[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows: In a first aspect, the composite membrane provided by this utility model includes a composite membrane body; The composite film body includes a first thermoplastic film and a second thermoplastic film stacked together. The first thermoplastic film and the second thermoplastic film are fixedly connected by ultrasonic welding, and a welding position is formed in the welding area. The composite film body has a printing area in the middle, and the welding position is located on the outer periphery of the printing area.

[0006] Furthermore, the composite membrane body is polygonal, and each corner of the composite membrane body has a welding position.

[0007] Furthermore, a plurality of welding positions are provided between the outer edge of the composite film body and the printing area, and the plurality of welding positions are arranged around the outer periphery of the printing area at intervals.

[0008] Furthermore, the composite film is used to be installed at the bottom of the material box body, and the first thermoplastic film is located above the second thermoplastic film; The first thermoplastic film is a release film, and the second thermoplastic film is a glossy film.

[0009] Furthermore, the second thermoplastic film has at least one vent hole, and the vent hole is offset from the welding position; The vent hole extends through the second thermoplastic film along the thickness direction of the second thermoplastic film.

[0010] Furthermore, the vent is located between the welding position and the printing area.

[0011] Furthermore, the composite film body is provided with positioning holes, which are located on the outer periphery of the printing area and are offset from the welding position; The positioning hole is used to insert and cooperate with the positioning post of the material box body.

[0012] Furthermore, there is a gap between the outer edge of the composite membrane body and the welding position.

[0013] Secondly, the 3D printing cartridge provided by this utility model includes a cartridge body and a composite film as described in any of the above claims; The composite film is installed at the bottom of the material box body.

[0014] Thirdly, the 3D printing equipment provided by this utility model includes the 3D printing material box as described above.

[0015] Based on the above technical solutions, the technical effects achievable by this utility model can be analyzed as follows: The composite film provided by this utility model includes a composite film body, which comprises a first thermoplastic film and a second thermoplastic film stacked together. The first and second thermoplastic films are fixedly connected by ultrasonic welding, forming a welding position in the welding area. A printing area is provided in the middle of the composite film body, and the welding position is located on the outer periphery of the printing area. The first and second thermoplastic films are connected by ultrasonic welding to form the composite film body. The composite film body can effectively control the ultraviolet transmittance passing through it, effectively ensuring that the transparent resin cures quickly in a short time, reducing the aging rate of the transparent resin, and preventing phenomena such as fogging, yellowing, and darkening of the transparent resin. The welding position is located on the outer periphery of the printing area to avoid affecting the normal printing function of the composite film.

[0016] This composite film body utilizes ultrasonic welding to firmly bond the first and second thermoplastic films, ensuring complete adhesion. By laminating the two films at the factory, transportation costs are reduced, and the problem of foreign matter easily adhering and causing material waste, which is common in existing technologies where two separate release films are stretched together, is avoided. The ultrasonic welding of the composite film body completely bonds the first and second thermoplastic films, solving the problem of release film detachment that occurs in existing technologies and improving the success rate of model printing. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the composite membrane provided in the embodiments of this application; Figure 2 for Figure 1 Cross-sectional view at point AA; Figure 3 This is a schematic diagram of the welding position in the composite membrane provided in the embodiments of this application; Figure 4 This is a schematic diagram of the end face structure of the welded joint.

[0019] icon: 100 - First thermoplastic film; 200 - Second thermoplastic film; 300 - Welding position; 310 - Welding point; 400 - Printing area; 500 - Vent hole; 600 - Welding head. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0023] Example 1 The composite film provided in this embodiment of the present invention includes a composite film body, which includes a first thermoplastic film 100 and a second thermoplastic film 200 stacked together. The first thermoplastic film 100 and the second thermoplastic film 200 are connected by ultrasonic welding, and a welding position 300 is formed in the welding area. A printing area 400 is provided in the middle of the composite film body, and the welding position 300 is located on the outer periphery of the printing area 400.

[0024] Specifically, the printing area 400 has the same shape as the composite film body and is located in the middle of the composite film body for printing.

[0025] The first thermoplastic film 100 and the second thermoplastic film 200 are joined together by ultrasonic welding to form a composite film body. The composite film body can effectively control the ultraviolet transmittance passing through it, ensuring rapid curing of the transparent resin in a short time, reducing the aging rate of the transparent resin, and preventing phenomena such as fogging, yellowing, and darkening. The welding position 300 is located on the outer periphery of the printing area 400 to avoid interfering with the normal printing function of the composite film.

[0026] This composite film body utilizes ultrasonic welding to completely bond the first thermoplastic film 100 and the second thermoplastic film 200 together. By bonding the two films at the factory, transportation costs are reduced, and the problem of foreign matter easily adhering and causing material waste when stretching two separate release films, as in existing technologies, is avoided. The ultrasonic welding of the composite film body completely bonds the first thermoplastic film 100 and the second thermoplastic film 200 together, solving the problem of release film detachment that occurs in existing technologies and improving the success rate of model printing.

[0027] The structure of the composite membrane is described in detail below: In an optional embodiment of this utility model, the composite membrane body is polygonal, and each corner of the composite membrane body has a welding position 300.

[0028] Specifically, in this embodiment, see Figure 1 and Figure 2 The composite membrane body is square, and each of the four corners has a welding position of 300.

[0029] Each corner of the composite film body has a welding position 300 to achieve stable fixation of the first thermoplastic film 100 and the second thermoplastic film 200.

[0030] In an optional embodiment of this utility model, a plurality of welding positions 300 are provided between the outer edge of the composite film body and the printing area 400, and the plurality of welding positions 300 surround the outer periphery of the printing area 400 and are spaced apart.

[0031] Specifically, multiple welding positions 300 are evenly arranged; in this embodiment, the distance between two adjacent welding positions 300 on the same side of the composite membrane body is set to 20mm; of course, other values ​​can be set for the distance, such as 15mm, 25mm or 30mm, which are all within the protection scope of this utility model embodiment.

[0032] Multiple welding positions 300 improve the connection strength between the first thermoplastic film 100 and the second thermoplastic film 200, improve the connection stability of the composite film body, and ensure the bonding stability of the first thermoplastic film 100 and the second thermoplastic film 200.

[0033] In an optional embodiment of this utility model, there is a gap between the outer edge of the composite membrane body and the welding position 300.

[0034] Specifically, in this embodiment, a welding area is formed between the outer edge of the composite film body and the printing area 400, and the welding position 300 is arranged in the middle of the welding area to ensure that the welding position 300 connects the first thermoplastic film 100 and the second thermoplastic film 200, and to avoid the welding position 300 affecting the printing area 400. Furthermore, the distance between the outer edge of the composite film body and the center of the welding position 300 is set to 5.6 mm. Experiments have shown that this distance results in good welding performance.

[0035] There is a gap between the outer edge of the composite membrane body and the edge of the welding position 300, ensuring that the welding position 300 is completely located on the composite membrane body. This avoids the problem that during the welding operation, the welding position 300 is partially located on the composite membrane body and the other part is located outside the composite membrane body, resulting in an incomplete welding position 300, which reduces the area of ​​the welding position 300 and leads to poor welding effect.

[0036] In an optional embodiment of this utility model, the composite film is used to be installed at the bottom of the material box body, and the first thermoplastic film 100 is located above the second thermoplastic film 200; the first thermoplastic film 100 is set as a release film, and the second thermoplastic film 200 is set as a glossy film.

[0037] Specifically, the composite film body is used to be installed at the bottom of the material box body. The first thermoplastic film 100 is made of materials including but not limited to ACF, FEP, NFEP, HTF, and TCF, and the second thermoplastic film 200 is made of materials including but not limited to PTFE, whitened ACF, frosted film, or glossy film.

[0038] The first thermoplastic film 100 is set as a release film, used to achieve non-destructive separation of the model from the printing platform during the photopolymerization 3D printing process; the second thermoplastic film 200 is set as a light-reflecting film, used to control light and also to scatter light, thereby improving the transparency of the printed parts.

[0039] In an optional embodiment of this utility model, the second thermoplastic film 200 has at least one vent hole 500, and the vent hole 500 is offset from the welding position 300; the vent hole 500 penetrates the second thermoplastic film 200 along the thickness direction of the second thermoplastic film 200.

[0040] Specifically, in the prior art, the release film at the bottom has vent holes. Because the composite film in this embodiment uses ultrasonic welding, resulting in good adhesion, the diameter of the vent hole 500 in this embodiment is smaller than the diameter of the vent hole in the prior art. The second thermoplastic film 200 needs to be perforated to form the vent hole 500 before welding. The vent hole 500 and the welding position 300 are misaligned, meaning that the vent hole 500 and the welding position 300 do not overlap. See also... Figure 2 The composite membrane body has ventilation holes 500 on both long sides, and the ventilation holes 500 on one side are located between two adjacent welding positions 300.

[0041] Vent hole 500 is used for ventilation; vent hole 500 is misaligned with welding point 310 to avoid affecting the welding effect.

[0042] In an optional embodiment of this utility model, the vent 500 is located between the welding position 300 and the printing area 400.

[0043] Specifically, during the release process, the first thermoplastic film 100 and the second thermoplastic film 200 can communicate with the outside world and balance the atmospheric pressure between the first thermoplastic film 100 and the second thermoplastic film 200, so that the first thermoplastic film 100 can more easily undergo elastic deformation during the release process. This reduces the release force at the release interface and lowers the difficulty of peeling the first thermoplastic film 100 from the printed part during the release process. This not only improves the surface flatness of the printed part, but also improves the release efficiency (that is, due to the reduction of the release force, the printed part is less likely to break, and the operator can speed up the release speed). This solves the problem that the release structure of the existing 3D printer is difficult to peel off and will lead to a decrease in the printing efficiency of the 3D printer. The vent 500 is located within the area enclosed by multiple welding positions 300, allowing direct ventilation between the first thermoplastic film 100 and the second thermoplastic film 200. Compared to the vent 500 being located outside the area enclosed by multiple welding positions 300, the gas does not need to flow through the gap between two adjacent welding positions 300 within the area enclosed by multiple welding positions 300 before flowing to the vent, thus shortening the gas flow path and making ventilation smoother.

[0044] In an optional embodiment of this utility model, the composite film body is provided with a positioning hole, which is located on the outer periphery of the printing area 400 and is offset from the welding position 300; the positioning hole is used to insert and cooperate with the positioning post of the material box body.

[0045] Specifically, the composite film body has multiple positioning holes, and the material box body has positioning posts corresponding to these holes. When using this composite film body, it needs to be installed to the bottom of the material box body using stretching or other methods. The positioning holes and positioning posts of the material box body should be matched. First, the positioning holes and positioning posts should be inserted and matched to initially position the composite film body, and then the composite film body should be fixed to the material box body.

[0046] The positioning hole and positioning post are inserted and matched to achieve positioning before the composite film is installed onto the material box body, thereby improving the installation accuracy of the composite film and the material box body.

[0047] In an optional embodiment of this utility model, the welding position 300 is circular.

[0048] Specifically, in this embodiment, a welding head 600 with a circular cross-section is used to perform ultrasonic welding on the second thermoplastic film 200 and the first thermoplastic film 100.

[0049] The welding position 300 is circular, which increases the welding area between the first thermoplastic film 100 and the second thermoplastic film 200 and improves the connection effect.

[0050] In the optional embodiments of this utility model, see Figure 3 The welding position 300 includes N rows and M columns of welding points 310, and each welding point 310 has the same shape.

[0051] Specifically, in this embodiment, see Figure 4 The second thermoplastic film 200 and the first thermoplastic film 100 are ultrasonically welded using a welding head 600 with N rows and M columns of "※" shaped protrusions on the end face; after welding, the welding position 300 of the welding head 600 is circular in shape and has N rows and M columns of square welding points 310 inside.

[0052] The following details the fusion welding steps for the composite membrane: Step 1: Place the positioning fixture on a flat operating table; Step 2: Use the "※" type 600 welding head and install it on the operating handle of the welding machine; Step 3: Adjust welding parameters; Step 4: Place the first thermoplastic film 100 at the bottom of the fixture and peel off the protective film on the upper side of the film; (the lower protective film is a partial overlay). Step 5: Place the second thermoplastic film 200 on top of the first thermoplastic film 100. Before placing it, remove the protective film on the bottom side of the first thermoplastic film (the upper protective film is a partial overlay). Step Six: Perform welding sequentially according to the set welding positions 300 (to ensure the reliability of welding and reduce the adverse effects of welding on the composite membrane body, the position and number of welding positions 300 need to be optimized and determined in advance).

[0053] Example 2 The 3D printing cartridge provided in this embodiment includes the composite film described in Embodiment 1, and therefore also possesses all the beneficial effects of Embodiment 1, which will not be repeated here.

[0054] In the optional embodiment of this utility model, the 3D printing cartridge includes a cartridge body and a composite film installed at the bottom of the cartridge body.

[0055] Specifically, the material box body is a cavity with openings at both ends. The composite film is installed at one open end of the material box body, sealing one end of the material box body. When installing the composite film, the first thermoplastic film 100 is closer to the material box body than the second thermoplastic film 200. In this embodiment, the composite film can be installed to the material box body in the form of a stretched film. When using this 3D printing material box, the end with the composite film is facing down.

[0056] The composite film is installed on the material box body, enabling the 3D printed material box to be used in 3D printing equipment.

[0057] Example 3 The 3D printing equipment provided in this embodiment includes the 3D printing material box described in Embodiment 2, and therefore also possesses all the beneficial effects of Embodiment 2, which will not be repeated here.

[0058] In the optional embodiment of this utility model, the 3D printing equipment includes a 3D printing cartridge, a lifting platform, and an exposure module. The exposure module is used to emit ultraviolet light. The lifting platform is located above the 3D printing cartridge, and the exposure module is located below the 3D printing cartridge. The 3D printing cartridge is fixed on the frame, and a composite film is installed at the bottom, wherein the first thermoplastic film 100 is located above the second thermoplastic film 200. The 3D printing cartridge is filled with liquid resin. During 3D printing, the three-dimensional model is first processed into layers to obtain the pattern information of each layer, and then the exposure module at the bottom is used to print the required liquid resin. Each printed pattern is illuminated onto liquid resin through the composite film in the 3D printing cartridge. The resin between the base plate of the elevator and the composite film is cured by the light, forming a cured layer. This cured layer adheres to the base plate of the elevator (or to the previous cured layer). After the pattern is cured, the elevator moves the cured layer a certain distance away from the exposure module, separating the cured layer from the composite film. The space between the cured layer and the composite film is then filled with liquid resin, and the next layer is cured. This process is repeated iteratively until a complete printed part (i.e., a 3D model) is formed.

[0059] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.

[0060] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A composite membrane, characterized in that, include: Composite membrane body; The composite film body includes a first thermoplastic film (100) and a second thermoplastic film (200) stacked together. The first thermoplastic film (100) and the second thermoplastic film (200) are fixedly connected by ultrasonic welding, and a welding position (300) is formed in the welding area. The composite film body has a printing area (400) in the middle, and the welding position (300) is located on the outer periphery of the printing area (400).

2. The composite membrane according to claim 1, characterized in that, The composite membrane body is polygonal, and each corner of the composite membrane body has a welding position (300).

3. The composite membrane according to claim 2, characterized in that, A plurality of welding positions (300) are provided between the outer edge of the composite film body and the printing area (400), and the plurality of welding positions (300) surround the outer periphery of the printing area (400) and are spaced apart.

4. The composite membrane according to claim 1, characterized in that, The composite film is used to be installed on the bottom of the material box body, and the first thermoplastic film (100) is located above the second thermoplastic film (200); The first thermoplastic film (100) is configured as a release film, and the second thermoplastic film (200) is configured as a glossy film.

5. The composite membrane according to claim 4, characterized in that, The second thermoplastic film (200) has at least one vent (500), and the vent (500) is offset from the welding position (300); The vent (500) extends through the second thermoplastic film (200) along the thickness direction of the second thermoplastic film (200).

6. The composite membrane according to claim 5, characterized in that, The vent (500) is located between the welding position (300) and the printing area (400).

7. The composite membrane according to claim 4, characterized in that, The composite film body is provided with positioning holes, which are located on the outer periphery of the printing area (400) and are offset from the welding position (300); The positioning hole is used to insert and cooperate with the positioning post of the material box body.

8. The composite membrane according to any one of claims 1-7, characterized in that, There is a gap between the outer edge of the composite membrane body and the welding position (300).

9. A 3D printing material box, characterized in that, Includes a material box body and a composite film as described in any one of claims 1-8; The composite film is installed at the bottom of the material box body.

10. A 3D printing device, characterized in that, Includes the 3D printing cartridge as described in claim 9.

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