A stereolithography method, a stereolithography apparatus, and a storage medium

Abstract

The application discloses a stereoscopic forming method, a stereoscopic forming device and a storage medium, which mainly forms a current printing layer through solidification, then forms a pigment layer, solidifies the pigment layer to adhere to the current printing layer, forms a color model through superposition, realizes one-time printing of the color model, does not need to be colored separately, and is flexible in color. The main technical scheme of the application is as follows: a stereoscopic forming method, comprising the following steps: adding printing material to a construction window, the printing material being in a covering position of the construction window and corresponding to a current printing layer of a to-be-printed model, controlling a printing platform to be close to the construction window, so that the printing material is solidified on the printing platform to form the current printing layer of the to-be-printed model, controlling the printing platform to be away from the construction window, removing the printing material on the construction window, spraying a layer of pigment layer on the construction window, the pigment layer corresponding to the current printing layer, and controlling the printing platform to be close to the construction window, so that the pigment layer is solidified on the current printing layer. The application is mainly used for printing a model.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, and in particular to a stereolithography method, stereolithography equipment and storage medium. Background Technology

[0002] 3D printers, also known as additive manufacturing equipment, achieve three-dimensional shapes by printing and stacking layers one by one. In common photopolymer 3D printers, the characteristic of resin undergoing a polymerization reaction under light is utilized. The light source is irradiated according to the cross-sectional shape of the object to be formed, causing the resin to solidify and take shape. The printing platform moves upward layer by layer, and then the layers are stacked one by one to achieve three-dimensional printing.

[0003] Existing methods for color model printing, such as using different colored resins to print models in multiple colors, only allow for segmented color changes along the printing direction, which is cumbersome and lacks flexibility. Alternatively, the printed model can be painted separately. For example, patent CN218876311U discloses a model painting device that rotates the model so that different sides face the painting mechanism, which then paints the model. However, this requires a separate painting process, preventing one-time printing, resulting in a long painting cycle, numerous devices, and negatively impacting user experience. Summary of the Invention

[0004] In view of the above, in order to solve at least one of the above technical problems, the present invention provides a stereolithography method, stereolithography equipment and storage medium.

[0005] To achieve the above objectives, the present invention mainly provides the following technical solutions:

[0006] On one hand, the present invention provides a stereolithography method applied to a stereolithography device for printing a model to be printed. The stereolithography device includes a building window and a printing platform. The stereolithography method includes:

[0007] Add printing material to the build window. The location of the printing material in the build window corresponds to the current printing layer of the model to be printed.

[0008] Control the printing platform to move closer to the build window so that the printing material solidifies on the printing platform, forming the current printing layer of the model to be printed;

[0009] Control the printing platform away from the build window and remove the printing material from the build window to spray a layer of pigment onto the build window, the pigment layer corresponding to the current printing layer;

[0010] Move the print platform closer to the build window to allow the pigment layer to solidify onto the current print layer.

[0011] On the other hand, the present invention also provides a stereolithography apparatus, comprising:

[0012] Memory, used to store computer programs;

[0013] A processor is used to execute computer programs to implement the steps of any of the aforementioned stereolithography methods.

[0014] In another aspect, the present invention also provides a computer-readable storage medium storing at least one executable instruction that causes a processor to perform the steps of the stereolithography method as described in any of the preceding claims.

[0015] This invention proposes a stereolithography method, stereolithography equipment, and storage medium. The method primarily involves first curing a current printing layer, then forming a pigment layer, and finally curing the pigment layer onto the current printing layer. This process, through stacking, forms a colored model, achieving one-time printing of the colored model without the need for additional coloring, and offering flexible color options. In existing technologies, if the printing material is changed, color changes can only be done segmentally along the printing direction, which is cumbersome and lacks flexibility in coloring. Alternatively, the printed model can be colored separately, requiring a separate coloring process, making one-time printing impossible. This process is time-consuming, requires numerous devices, and negatively impacts user experience. In contrast, this application first prints the printing layer, then removes the printing material from the build window, forming a pigment layer on the build window. The printing layer is then moved to contact the pigment layer, and the pigment layer is cured onto the printing layer, resulting in a stacking of the printing and pigment layers. Each printing layer and its corresponding pigment layer are printed sequentially, with the pigment layer sandwiched between the printing layers. The model displays color through the printing layers, achieving one-time printing of the colored model. Furthermore, the color of the pigment layer can be changed by spraying pigment, making the colored model's color flexible and diverse. Another approach involves forming the current printing layer through a printing platform. The printing layer is formed by controlling the lifting and lowering of the printing platform, making printing easier to control and more accurate. The pigment layer is then formed on the build window instead of printing the pigment directly onto the current printing layer, making the pigment layer spraying more precise. The pigment layer is lowered by the printing platform, allowing the current printing layer and the pigment layer to adhere and solidify together. The curing position of both is highly accurate, the color printing method is simple, and the adaptability is high. Attached Figure Description

[0016] Figure 1 A flowchart of a stereolithography method provided in an embodiment of the present invention;

[0017] Figure 2 A flowchart of another stereolithography method provided in an embodiment of the present invention;

[0018] Figure 3 A flowchart of another stereolithography method provided in an embodiment of the present invention. Detailed Implementation

[0019] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description of the specific implementation method, structure, features and effects of the three-dimensional forming method proposed according to the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0020] This invention provides a stereolithography method for printing a model using a stereolithography device. The stereolithography device includes a build window and a printing platform. The build window is used for release molding, meaning it separates from the printed material layer or pigment layer after the latter has cured. The build window can also be light-transmitting or light-emitting to cure the printed material above it, forming the current printed layer and pigment layer. The build window can take various forms. For example, it can be a display screen of the stereolithography device, which can be used for release molding by directly contacting the printed material or pigment layer. Alternatively, the stereolithography device may also include a material tank, which includes a receiving cavity and a release film. The release film is part of the cavity wall and serves as the build window. Alternatively, the material tank may be entirely transparent, in which case the build window is the area corresponding to the bottom light source or display screen of the stereolithography device. In the following embodiments, an example is used where the material tank includes a release film, and the printing platform is opposite to the release film in the material tank, with the release film serving as the build window.

[0021] In some embodiments, the stereolithography equipment further includes a nozzle unit, a feeding / discharging assembly, a material trough, and a curing unit, with the feeding / discharging assembly communicating with the receiving cavity. Furthermore, the stereolithography equipment may also include a main support structure, an XY moving mechanism, and a lifting mechanism. The main support structure has a light-transmitting opening that covers the display screen. The material trough is placed on the main support structure, and the release film is opposite to the display screen. The XY moving mechanism is connected to the main support structure, and the nozzle unit is connected to the XY moving mechanism, which drives the nozzle unit to move in an XY plane parallel to the release film. The lifting mechanism is connected to the main support structure, and the printing platform is connected to the lifting mechanism, which drives the printing platform to move towards or away from the release film.

[0022] The stereolithography method can be executed using a controller for stereolithography equipment. The XY movement mechanism, lifting mechanism, nozzle unit, and feeding / discharging components are all electrically connected to the controller. The controller can be a control chip. In one embodiment, such as... Figure 1 As shown, the three-dimensional forming method includes:

[0023] S1-1. Add printing material to the build window. The printing material's coverage area in the build window corresponds to the current printing layer of the model to be printed.

[0024] The printing material can cover only a portion of the build window or cover the entire build window. The area covered by the printing material should be larger than the area corresponding to the current print layer to ensure that the current print layer can be fully formed, thus reducing the amount of printing material added.

[0025] In some implementations, when printing the model to be printed, it is necessary to print the supports of the model simultaneously. For example, when printing a model with lateral abrupt changes, it is necessary to print the supports simultaneously between the abrupt change region and the printing platform. The correspondence between the coverage position of the printing material in the build window and the current printing layer of the model to be printed means that it corresponds at least simultaneously with both the model itself and its corresponding supports.

[0026] The feeding and discharging assembly can fill or discharge printing material into the receiving cavity in various ways. For example, it can use a hose, a peristaltic pump and a material bottle. The two ends of the hose are connected to the receiving cavity and the material bottle cavity, respectively. The peristaltic pump is set on the hose. The printing material in the material bottle can be introduced into the receiving cavity through the forward drive and reverse drive of the peristaltic pump, or the printing material in the receiving cavity can be returned to the material bottle cavity.

[0027] Printing materials are materials that change from a liquid to a solid state when exposed to light of a specific color or frequency, such as resin. To allow the color of the pigment to be expressed through the printing layer, the printing layer is a light-transmitting layer, meaning the printing material is a light-transmitting printing material, specifically, it can be a transparent printing material.

[0028] The height to which printing material is added should be greater than the thickness of the current printed layer, but not necessarily too high, to avoid wasting too much time during feeding and discharging. For example, when controlling the feeding / discharging components to add printing material to the build window, the thickness of the printing material should be greater than or equal to the thickness of the current printed layer; that is, the distance from the liquid surface of the printing material to the release film should be greater than the thickness of the current printed layer, but less than twice the thickness of the current printed layer. Optionally, the height to which the printing material is added should be less than or equal to 3 mm. More specifically, the feeding / discharging components add a preset amount of printing material into the receiving cavity, set according to the capacity of the material tank, such as the length and width of the receiving cavity, and the required height of the liquid surface of the printing material, thereby calculating the required amount to be added each time.

[0029] Alternatively, the stereolithography equipment may also include a liquid level sensor, which can be an infrared sensor or a probe-type sensor, positioned opposite the receiving cavity. The feeding and discharging components continuously add printing material into the receiving cavity of the material tank. The equipment receives the liquid level height data from the liquid level sensor, determines the relationship between the liquid level height and a preset liquid level height, and stops adding printing material into the receiving cavity when the preset liquid level height is reached, thus achieving quantitative addition of printing material.

[0030] Alternatively, the stereolithography equipment may also include a weight sensor connected to the material tank, specifically positioned between the material tank and the support, such as a combination of a cantilever and elastic strain gauges. The feeding / discharging assembly continuously adds printing material into the receiving cavity, receives the weight value from the weight sensor, determines the relationship between the weight value and a preset weight, and stops adding printing material into the receiving cavity when the weight value reaches the preset weight, thus achieving quantitative addition of printing material.

[0031] Alternatively, the feeding and discharging components can be controlled to add printing material into the receiving cavity of the material tank within a preset time. For example, the required feeding amount can be calculated based on the flow rate of the feeding and discharging components and the amount of printing material to be added to the receiving cavity, and then the material can be fed at a certain flow rate within the feeding time to achieve control of the feeding amount.

[0032] S1-2. Control the printing platform to move closer to the build window so that the printing material is solidified on the printing platform to form the current printing layer of the model to be printed.

[0033] The printing platform is moved toward the construction window by a lifting mechanism, so that at least part of the printing material is sandwiched between the release film and the printing platform, or between the release film and the formed model. By irradiation, at least part of the printing material can be cured according to the shape of the current printing layer to form the current printing layer.

[0034] Specifically:

[0035] S1-2-1. Control the printing platform to move closer to the build window so that the distance between the printing platform and the build window corresponds to the distance required for the current printing layer of the model to be printed.

[0036] The printing platform is controlled to move closer to the release film until at least the bottom surface of the printing platform, or the bottom surface of the molded model, is immersed in or in contact with the printing material, and moves to the distance required to separate the current printed layer from the release film. When no model is connected to the printing platform, i.e., the current printed layer is the first layer of the model, the distance between the printing platform and the build window is the thickness of one model layer, i.e., the thickness of the current printed layer. In embodiments where a printed model is already connected to the printing platform, such as embodiments where color model printing starts from the middle, the distance between the printing platform and the build window is the sum of the thickness of the molded model connected to the printing platform and the thickness of the current printed layer, i.e., the distance between the molded model and the release film is the thickness of the current printed layer. It can be understood that if there is no molded model, the thickness of the molded model is 0.

[0037] It is understandable that even for the same model to be printed, the thickness of different printing layers may vary.

[0038] S1-2-2. According to the contour information of the current printing layer, control the curing light to irradiate the printing material so as to form the current printing layer of the model to be printed on the surface of the printing platform or on the completed model of the model to be printed on the printing platform.

[0039] Specifically, the stereolithography equipment also includes a curing unit located on the side of the release film opposite to the printing platform, such as at the bottom of the release film, with light shining upwards onto it. The curing unit is controlled to illuminate the printing material within the receiving cavity according to the contour of the current printed layer, causing the printing material to cure between the release film and the printing platform to form the current printed layer. The curing unit can emit only a beam of light, and the display screen can be a gated screen, allowing the light to pass through according to the contour of the current printed layer and illuminate the release film, thereby curing the current printed layer. Alternatively, the curing unit can directly emit light along the contour of the current printed layer; for example, the curing unit could be an OLED display screen.

[0040] S1-3. Control the printing platform away from the build window and remove the printing material on the build window to spray a layer of pigment onto the build window, the pigment layer corresponding to the current printing layer.

[0041] Controlling the print platform away from the build window can specifically involve moving the print platform to a preset height. The height of the print platform movement should accommodate the separation of the current printed layer and allow space for the bottom of the print platform or the attached molded model to make way for the ink spraying structure. More specifically, the preset height is the sum of the base height and the thickness of the attached molded model, while the base height is greater than the vertical distance from the top of the nozzle unit used for ink spraying to the release film, such as 5 mm greater.

[0042] The feeding / discharging assembly discharges the printing material from the build window. For pigment spraying, the printing material needs to be discharged to expose the release liner, which then receives the pigment. As described in the previous embodiment, the feeding / discharging assembly can be a hose, a peristaltic pump, and a cartridge bottle. The peristaltic pump rotates in the opposite direction to the direction of printing material addition, causing the printing material in the receiving cavity to flow back to the cartridge bottle cavity, or back to the transfer slot on the cartridge tray, until the release liner is fully exposed.

[0043] The purpose of removing the printing material is simply to ensure that the release film is exposed within the required range; it is not necessary to remove all the printing material from the cavity. In one embodiment, if the release film is located at the bottom of the cavity in the height direction, then all the printing material in the cavity needs to be removed. Alternatively, since the release film is a plane, if the printing material is not completely removed in areas that do not affect ink spraying, it will not affect the subsequent printing of the model.

[0044] Specifically, the extraction time can be determined based on the weight of the added printing material and the material discharge speed. If complete extraction of the printing material is required, the extraction time can be increased to ensure complete removal. Alternatively, in embodiments of the stereolithography equipment that include a liquid level sensor, the liquid level sensor can be used to determine whether the printing material in the tank has been completely extracted. Alternatively, a weight sensor can be used to obtain the weight information of the tank, and whether the weight is the same as the original weight of the tank can be used to determine whether the printing material has been completely extracted. Alternatively, the printing material can be discharged at a preset flow rate for a preset time. The preset flow rate and preset time can be the same as or greater than the flow rate and time during feeding.

[0045] Specifically, spraying a layer of pigment onto the build window can be done by spraying a layer of pigment onto the build window according to the color information of the current print layer.

[0046] The pigment layer is a liquid layer or a state between solid and liquid, and it adheres to the release film. There are various methods for forming the pigment layer, such as liquid spraying followed by curing, or other methods capable of forming a pigment layer. More specifically, the stereolithography equipment also includes a nozzle unit and a curing unit, and the pigment layer can be achieved in the following ways:

[0047] The control nozzle unit sprays pigment into the build window according to the color information of the current print layer to form a pigment layer.

[0048] The pigment can be cured under light of a set color or wavelength, such as ultraviolet or violet light. The pigment can be stored in a negative pressure container and includes various colors, such as black, white, red, yellow, and blue; or white, cyan, magenta, yellow, and black. The stored colors can be applied as needed, or the pigments can be mixed to obtain the desired spray color, such as green or purple. The color mixing process can be carried out in a dedicated mixing chamber within the printhead unit, or a separate dedicated mixing device can be used. Alternatively, the pigments can be sprayed onto the release film and mix naturally through molecular motion; this application does not impose any limitations. The negative pressure container can continuously supply pigment to the printhead unit, which has multiple controllable discharge holes. The color and spraying position can be controlled by opening and closing these holes, allowing the printhead unit to spray pigment onto a specific area of ​​the release film as required. The printhead unit is controlled to move relative to the release film by controlling the XY moving mechanism, and the pigment is sprayed onto the release film according to the color information of the current printed layer. The pigment will drip onto the release film.

[0049] Specifically, the color information of the current printed layer includes the spraying area, which refers to the entire area covered by the pigment after the current pigment spraying is completed. The spraying area should be located at least below the current printed layer during its formation, and should be at least within the forming area of ​​the current printed layer. The color corresponding to the current printed layer can be a single color, such as only red, in which case red pigment can be continuously applied to the spraying area. Alternatively, in some embodiments, the color corresponding to the current printed layer may be multiple colors, such as half of the area being red and the other half being yellow, in which case color changes need to be performed during the spraying process, and the coating is applied to different areas. If the spraying area includes at least one sub-spraying area, the color information of the current printed layer also includes the color information corresponding to the sub-spraying area. The step of controlling the nozzle unit to spray pigment onto the release film in the material tank according to the color information of the current printed layer specifically includes: controlling the nozzle unit to spray pigment onto the construction window according to the sub-spraying area and color information.

[0050] When the current printing layer corresponds to a single color, there is one sub-spraying area. The color information corresponding to this sub-area is the color that the current printing layer needs to display, such as the red color in the example above. When the current printing layer corresponds to multiple colors, there are multiple sub-spraying areas, such as the two sub-spraying areas in the example above. The color information corresponding to each sub-spraying area is the color that different areas of the current printing layer need to display, such as red and yellow color information for the two sub-spraying areas respectively. During the spraying process, the spraying of colors in different areas is performed by controlling the openable and closable discharge holes on the printhead unit. For example, red pigment can be sprayed in one spraying area first, and then yellow pigment can be sprayed in another spraying area. Alternatively, the discharge holes on the printhead unit can be controlled to allow two spraying areas to be sprayed with different colors of pigment simultaneously. Or, different colors of pigment can be sprayed from the printhead unit, causing the different colors of pigment to mix and form a new color of pigment.

[0051] The pigment layer corresponds to the current printed layer, allowing the sprayed pigment to cover the previously formed printed layer. To ensure the finished model displays color, the pigment should extend to the edge of the current printed layer in areas where color is desired, while the center areas away from the edge do not necessarily require pigment coverage. Therefore, the spraying area can be set in several ways:

[0052] In the first setting method, the outline of the spraying area is consistent with the outline of the current printed layer. In other words, the spraying area can be consistent with the outline of the light spot projected onto the release film when the curing unit cures the current printed layer, so that after molding, the pigment can completely cover the bottom surface of the current printed layer. This will be explained in more detail below.

[0053] In the second setting method, a portion of the outline of the spraying area matches a portion of the outline of the current printed layer. This setting method corresponds to two possible scenarios. The first scenario is that only a portion of the current printed layer needs to be colored, such as only the left half of the area needs to be colored while the right half does not. In this case, the spraying area only needs to have a portion of its outline match the outline of the side of the current printed layer that needs to be colored. The second scenario is that the pigment does not need to cover the entire bottom surface of the current printed layer, but only a portion of the extended edge of the current printed layer. For example, if the spraying area is a preset width area matching the outline of the current printed layer, after the current printed layer is formed, the spraying area is an area extending to the edge of the current printed layer outline and a preset width away from the edge of the current printed layer outline. For example, it can be a ring-shaped area with a preset width of 1 mm to 10 mm, etc., so that the color of the pigment layer is reflected at the edge of the current printed layer, while it is not reflected in the middle area that may be covered by the next printed layer. This aims to reduce spraying time and pigment usage without affecting the color rendering effect of the model. In the previous implementation method of printing supports simultaneously during model printing, the outline of the current printing layer refers to the overall outline of the model to be printed and the supports.

[0054] S1-4. Move the printing platform closer to the build window so that the pigment layer is cured on the current printing layer.

[0055] A lifting mechanism moves the printing platform towards the build window, bringing the current printing layer closer to the pigment layer until the current printing layer contacts the pigment layer, thus solidifying the pigment layer onto it and coloring the current printing layer. Controlling the movement of the printing platform towards the build window ensures contact between the printing platform and the pigment layer. Specifically, the distance between the printing platform and the build window can be a preset distance or the distance required for the current printing layer of the model to be printed.

[0056] The preset distance can be the distance required for the current pigment layer. The distance required for the current printing layer is the thickness of the formed model connected to the printing platform, as shown in the position of the printing platform in step S1-2-1. It is worth noting that the pigment layer is very thin and will not protrude significantly from the release film. When the printing platform descends to the position where the current printing layer has solidified, the pigment layer will not cause much resistance or pressure to the movement of the current printing layer, nor will it have a significant impact on the height of the model to be printed. Alternatively, the pigment layer can be placed within the model slicing process, and the preset distance would be the thickness of the formed model connected to the printing platform plus the thickness of the pigment layer. In reality, the thickness of the pigment layer can be ignored.

[0057] To solidify the pigment layer onto the current printed layer, a re-exposure can be achieved through a curing unit. The pigment is liquid; after being ejected from the nozzle unit, it remains liquid when dripping onto the release film. To ensure the pigment adheres to the previously printed current layer, it needs to be exposed by the curing unit, thus solidifying it. For complete pigment curing, the projection area of ​​light onto the release film must be at least equal to the pigment's spraying area. In one embodiment, the curing unit is controlled to irradiate the pigment according to a preset contour with a coverage area larger than the pigment's outline. This means the curing unit is controlled to irradiate the pigment according to the preset contour, ensuring the projection area onto the release film exceeds the pigment's spraying area, thereby guaranteeing complete pigment curing. Alternatively, in another embodiment, the curing unit can be controlled to irradiate the pigment according to the contour of the current printed layer. This means the curing unit irradiates the pigment according to the light used to cure the current printed layer, ensuring the light intensity on the cured pigment layer and the current printed layer is consistent. This reduces the control burden on the curing unit, simplifying the control process; only identical light emission from both sides is required based on the printing process. Alternatively, in some other implementations, the curing unit can be controlled to irradiate the pigment according to the coverage area of ​​the pigment. For example, in the implementation above, where the spraying area only needs to cover part of the current printing layer, only the area where the pigment is located can be irradiated. If the pigment is a ring-shaped pigment that extends to the edge of the current printing layer, only the ring-shaped light projection corresponding to the spraying area needs to be generated, which can reduce the amount of light projected, thereby saving energy and reducing the heating of the printing material and display screen caused by irradiation.

[0058] Since the pigment is liquid when sprayed onto the release film, in order to avoid the pigment being unstable, flowing out, mixing colors, or moving under the pressure of the printed layer, the pigment can be cured after spraying or during the spraying process.

[0059] The stereolithography method further includes, after controlling the printing platform to move close to the build window so that the pigment layer solidifies on the current printing layer:

[0060] Repeat the following steps: First, take the layer below the current printed layer as the current printed layer. Then, control the printing platform to move to the release height so that the current printed layer carries the pigment layer away from the build window. Next, add printing material to the build window, with the material's coverage area corresponding to the current printed layer of the model to be printed. Then, move the printing platform closer to the build window to print the current printed layer of the model on the printing platform. Finally, move the printing platform away from the build window and remove the printing material from the build window to spray a pigment layer onto the build window, corresponding to the current printed layer. Next, move the printing platform closer to the build window to allow the pigment layer to solidify on the current printed layer. Continue this process until the model to be printed is complete.

[0061] You can repeat the above steps of this application until the model to be printed is completed.

[0062] like Figure 2 As shown, this application also provides another method for stereolithography, including:

[0063] S2-1. Add printing material to the build window. The printing material's coverage area in the build window corresponds to the current printing layer of the model to be printed.

[0064] S2-2. Control the printing platform to move closer to the build window so that the printing material is solidified on the printing platform to form the current printing layer of the model to be printed.

[0065] S2-3. Move the printing platform away from the build window and remove the printing material from the build window to spray a layer of pigment onto the build window, the pigment layer corresponding to the current printing layer.

[0066] The descriptions of steps S2-1 to S2-3 can be found in the descriptions of steps S1-1 to S1-3 in the aforementioned implementation method.

[0067] S2-4. While or after spraying a layer of pigment onto the build window, control the curing unit to irradiate the pigment layer so that the surface of the pigment layer in contact with the build window is cured, while the surface of the pigment layer away from the build window is at least partially uncured.

[0068] The curing unit controls the irradiation of the pigment layer, partially curing it and fixing it to the release film. This prevents overflow or color shifting, ensuring accurate coloring. Liquid pigments exhibit oxygen inhibition, meaning they readily polymerize and cure in the absence of oxygen, but struggle to polymerize upon contact. For pigments sprayed onto the release film, the side in contact with the film is in an oxygen-free environment, allowing for curing under stimuli such as light. The surface in contact with the release film then cures. The surface of the pigment layer furthest from the build window remains uncured, either completely or partially, in a liquid or semi-liquid state. When the current print layer descends to contact the pigment layer and is then exposed again, the liquid surface of the pigment layer cures on this print layer, adhering to it. This achieves both coloring accuracy and adhesion between the pigment layer and the print layer.

[0069] The curing of the pigment layer includes a first curing process, which occurs simultaneously with or after the application of a pigment layer, and a second curing process, which occurs after the current printed layer comes into contact with the pigment layer. The second curing uses the same light source as the current printed layer, while the first curing can be performed using either the same light source or an additional light source. During the second curing process, the surface of the pigment layer furthest from the build window comes into contact with the model, where there is no oxygen, thus allowing it to solidify easily.

[0070] More specifically, the curing unit includes a single curing element, which can be a UV lamp. The curing element is located on the side of the printing platform opposite to the build window. The light emitted by the curing element passes through the display screen and the release film and acts on the pigment. The curing element is used to irradiate the pigment layer and also to irradiate the printing material to form the current printed layer. At this time, the curing element needs to irradiate the pigment layer twice to achieve the first curing and the second curing of the pigment layer. Similar to the aforementioned implementation, in order to ensure that the pigment can be cured at least on the release film side, the projection area of ​​the light on the release film should be at least larger than the area of ​​the pigment spraying.

[0071] In one embodiment, the curing unit is controlled to irradiate the pigment according to a preset outline with a coverage area larger than the pigment outline. Alternatively, the curing unit can be controlled to irradiate the pigment according to the outline of the current printing layer. Or, the curing unit can be controlled to irradiate the pigment according to the outline of the pigment. Further details will not be provided here.

[0072] The first and second curing of the pigment layer can also employ different, completely independent light-generating devices. In one embodiment, the curing unit includes a first curing element and a second curing element. The first curing element is located on the side of the build window closer to the printing platform, used to irradiate the pigment layer for the first curing. The second curing element is located on the side of the build window opposite the printing platform, used to irradiate the printing material to form the current printed layer, and to irradiate the pigment layer for the second curing. The first curing element can be a UV (Ultraviolet) lamp, located on the side of the release film closer to the printing platform, with the light emitted by the first curing element acting on the pigment. The first curing element can be connected to the printhead unit and driven to move via an XY drive mechanism, thereby achieving the movement and curing of the pigment. During the pigment spraying process by the printhead unit, the pigment can be continuously moved and cured. The light source can be a line light source, scanning the entire spraying area, thereby reducing the operating cost of the first curing element and preventing heat generation caused by the irradiation of the display screen and release film from below.

[0073] Furthermore, the first curing of the pigment layer can be performed either after spraying is completed or during the spraying process. If the curing unit includes a single curing element, continuous exposure can be performed while spraying the pigment, followed by the first curing during the spraying process; alternatively, a single exposure can be initiated after spraying is completed. In the implementation of the first curing element moving for curing, moving for curing can be performed after spraying is completed, or continuous curing can be performed during the moving process. By curing while spraying, both localized and timely curing can be achieved, avoiding light waste and increased printing material temperature caused by projecting a large area light source before spraying, and avoiding delayed curing, pigment mixing, and overflow caused by turning on the light source after spraying. A single curing method after spraying can save exposure time and avoid heat generation caused by prolonged exposure.

[0074] S2-5. Move the printing platform closer to the build window so that the pigment layer is cured on the current printing layer.

[0075] Due to the oxygen inhibition effect of pigments, the surface of the pigment layer far from the build window, i.e., the upper surface, will not be completely cured and will remain in a liquid or semi-liquid state. The current print layer descends to contact the pigment layer, and a second curing of the pigment layer occurs, causing the liquid upper surface of the pigment layer, or the liquid area on the upper surface, to solidify on this print layer and then adhere to it.

[0076] like Figure 3 As shown, the present invention also provides a stereolithography method for use in a stereolithography apparatus. The stereolithography apparatus can be consistent with the aforementioned embodiments of stereolithography apparatus, and will not be described again here. The stereolithography method includes:

[0077] S3-1. Obtain the color information corresponding to the current printing layer.

[0078] Color information can be obtained through local file reading, external storage, or cloud platform. The color information includes the sprayed area and the corresponding color information, which is the color of the printed layer within that area.

[0079] S3-2, Use one of the multiple printing layers as the current printing layer.

[0080] The current printing layer can be either the first layer or any layer in the middle of the model. For example, if the current printing layer is the middle layer, color printing can begin in the latter half of the model printing process. It should be noted that if the current printing layer is the middle layer, the printing material in the sprue must first be discharged until the release film is exposed, and the squeegee must be controlled to push the printing material. This will be described in detail later. If the current printing layer is the first layer, there is no need to discharge the printing material or perform the squeegee process.

[0081] S3-3, Control the printing platform to move to the initial position.

[0082] Since the printhead unit has a certain height, it will occupy a certain space to move, and the moving position is above the release film, which conflicts with the position of the printing platform when it participates in the curing of the curing layer. In order to make way for the printhead unit, the initial position of the printing platform refers to the printing platform moving away from the release film, and then rising to a position higher than the top of the printhead unit, so as to make way for the printhead unit to move and spray the pigment.

[0083] S3-4. Add printing material to the build window. The printing material's coverage area in the build window corresponds to the current printing layer of the model to be printed.

[0084] S3-5. Control the printing platform to move closer to the build window so that the distance between the printing platform and the build window corresponds to the distance required for the current printing layer of the model to be printed.

[0085] S3-6. According to the contour information of the current printing layer, control the curing light to irradiate the printing material so as to form the current printing layer of the model to be printed on the surface of the printing platform or on the completed model of the model to be printed on the printing platform.

[0086] S3-7. Control the printing platform to move away from the build window and remove the printing material on the build window. Control the scraper unit to scrape off the printing material above the build window so as to spray a layer of pigment on the build window. The pigment layer corresponds to the current printing layer.

[0087] The stereolithography equipment also includes a scraper unit, which mainly consists of a scraper and a flip drive. The scraper unit can be connected to the printhead unit, the XY drive mechanism, or a separate scraper movement mechanism. Taking the connection between the scraper unit and the XY drive mechanism as an example, the flip drive is connected to the XY drive mechanism via a support plate, and the scraper is connected to the flip drive. The flip drive can be a servo motor, and the scraper is connected to the output shaft of the servo motor. The scraper can extend in the length or width direction of the material trough, such as extending in the width direction, with an extension length consistent with or slightly larger than the release film. The XY drive mechanism drives the scraper to move along the length direction of the material trough, scraping and pushing the remaining printing material on the release film to one side of the receiving cavity or into a storage device connected to the receiving cavity. The scraper's position includes a pushing position and a receiving position. In the pushing position, the bottom of the scraper is closer to the build window than in the receiving position.

[0088] During the ink spraying process of the printhead unit, the flip drive moves the squeegee to a horizontally extended, i.e., retracted position, so that the bottom of the squeegee is away from the release film. At this time, the discharge port at the bottom of the printhead unit is at its lowest position, and it can then move and spray above the release film. The distance between the bottom of the printhead unit and the release film can be greater than 0 mm and less than 5 mm to ensure the accuracy of the moving spray and the spraying. When it is necessary to remove the printing material from the release film, the flip drive moves the squeegee to a vertically extended or downwardly inclined extended, i.e., scraping and pushing position, so that the bottom of the squeegee is close to the release film. At this time, the bottom of the squeegee is lower than the bottom of the printhead unit, and the bottom of the squeegee is at its lowest position, slightly lower than the top surface of the release film. It can then move under the drive of the XY drive mechanism to scrape and push the printing material above the release film. In one embodiment, the squeegee is a silicone squeegee, and the silicone squeegee is coated with fluorine to avoid printing material residue on the squeegee.

[0089] The process of controlling the scraper unit to scrape off the printing material above the build window includes: controlling the flip drive to move the scraper to the scraping position; controlling the scraper to move so that the scraper scrapes off the printing material above the build window; and controlling the flip drive to move the scraper to the storage position.

[0090] The squeegee design ensures a clean release film, reduces printing material residue, and allows the next layer of pigment to cure directly on the release film. This avoids the pigment layer thickening caused by printing material between the pigment and the release film, and also prevents the pigment from overflowing due to the mixing of printing material residue and pigment.

[0091] In some implementations, after controlling the printing platform away from the build window, it can be directly moved to a position where the formed model and the release film are separated by one model layer. Then, it is illuminated according to the outline of the next model layer to form the next model layer, achieving printing with only a print layer and no pigment layer. This printing can continue in multiple layers, followed by color printing, i.e., removing the print material from the build window by controlling the doctor blade unit to scrape off the print material above the build window. This simplifies the printing process, and because the single-layer model is relatively thin, color will still be visible even with multiple print layers sandwiched between adjacent pigment layers.

[0092] S3-8. While or after spraying a layer of pigment onto the build window, control the curing unit to irradiate the pigment layer so that the surface of the pigment layer in contact with the build window is cured, while the surface of the pigment layer away from the build window is at least partially uncured.

[0093] S3-9. Move the print platform closer to the build window so that the pigment layer is cured on the current print layer.

[0094] The descriptions of steps 3-4 to 3-9 can be found in the descriptions of steps S1-1 to S1-4 and S2-4 in the foregoing embodiments, and will not be repeated here.

[0095] The release height is the height of the release film at which the current printed model completely separates from the pigment layer. It doesn't need to be too high to ensure printing efficiency. The adhesion between model layers and between the current printed layer and the pigment layer will be much greater than the adhesion between the pigment layer and the release film. As the printing platform moves upward, the pigment layer will detach from the release film under the influence of the current printed layer, and then it can be considered as a single unit, participating together in the printing of the next model layer.

[0096] In one embodiment, the stereolithography apparatus further includes a memory for storing computer programs;

[0097] A processor is used to execute a computer program to implement any of the steps of a stereolithography method.

[0098] In one embodiment, the present invention also provides a computer-readable storage medium storing at least one executable instruction that causes a processor to perform any of the steps of a stereolithography method.

[0099] Based on this understanding, the technical solution of this application can be embodied in the form of a software product. The software product to be identified can be stored in a non-volatile storage medium, such as a CD-ROM, USB flash drive, or portable hard drive, and includes several instructions to enable a computer device, such as a personal computer, server, or network device, to execute the stereolithography method of this application.

[0100] This application also provides the following implementation methods:

[0101] Serial number 1. A stereolithography method, applied to a stereolithography device, for printing a model to be printed, the stereolithography device including a building window and a printing platform, the stereolithography method including:

[0102] Add printing material to the build window. The location of the printing material in the build window corresponds to the current printing layer of the model to be printed.

[0103] Control the printing platform to move closer to the build window so that the printing material solidifies on the printing platform, forming the current printing layer of the model to be printed;

[0104] Control the printing platform away from the build window and remove the printing material from the build window to spray a layer of pigment onto the build window, the pigment layer corresponding to the current printing layer;

[0105] Move the print platform closer to the build window to allow the pigment layer to solidify onto the current print layer.

[0106] Serial number 2, according to the stereolithography method of serial number 1, wherein controlling the printing platform to be close to the construction window so that the printing material is solidified on the printing platform to form the current printing layer of the model to be printed includes:

[0107] Control the printing platform to move closer to the build window so that the distance between the printing platform and the build window corresponds to the distance required for the current printing layer of the model to be printed;

[0108] Based on the contour information of the current printing layer, control the curing light to irradiate the printing material, so as to form the current printing layer of the model to be printed on the surface of the printing platform, or on the completed model of the model to be printed on the printing platform.

[0109] Item 3, according to the stereolithography method in Item 1, wherein controlling the printing platform to approach the build window so that the pigment layer is cured on the current printing layer includes:

[0110] Control the print platform to move closer to the build window, with the distance between the print platform and the build window set to a preset distance; or,

[0111] Control the print platform to move closer to the build window. The distance between the print platform and the build window corresponds to the distance required for the current print layer of the model to be printed.

[0112] Serial number 4, according to the stereolithography method of serial number 1, wherein the stereolithography equipment further includes a curing unit, and the method further includes, simultaneously or after spraying a layer of pigment onto the construction window:

[0113] The curing unit is controlled to irradiate the pigment layer so that the surface of the pigment layer in contact with the build window is cured, while the surface of the pigment layer away from the build window is at least partially uncured.

[0114] Item 5, according to the three-dimensional forming method of Item 1, wherein spraying a layer of pigment onto the construction window includes:

[0115] Spray a layer of pigment onto the build window according to the color information of the current print layer.

[0116] Serial number 6, according to the stereolithography method of serial number 1, wherein the stereolithography equipment includes an infeed / outfeed assembly, and adds printing material to the building window, including:

[0117] Control the feeding and discharging components to add printing material to the build window. The thickness of the printing material is greater than or equal to the thickness of the current printing layer.

[0118] Item 7. According to the stereolithography method in Item 5, the stereolithography equipment further includes a nozzle unit and a curing unit. Based on the color information of the current printing layer, a pigment layer is sprayed onto the construction window, specifically including:

[0119] The control nozzle unit sprays pigment into the build window according to the color information of the current print layer to form a pigment layer.

[0120] Serial number 8, according to the stereolithography method in serial number 7, wherein the color information of the current printed layer includes a spraying area, the spraying area includes at least one sub-spraying area, and the color information of the current printed layer also includes the color information corresponding to the sub-spraying area. The printhead unit is controlled to spray pigment onto the construction window according to the color information of the current printed layer, specifically including:

[0121] The control nozzle unit sprays pigments onto the construction window according to the sub-spraying area and color information.

[0122] Serial number 9, according to the three-dimensional forming method in serial number 8, wherein,

[0123] The outline of the sprayed area matches the outline of the current printed layer;

[0124] Alternatively, a portion of the outline of the sub-sprayed area may match a portion of the outline of the current printed layer.

[0125] Alternatively, the spraying area can be a region of a preset width that matches the outline of the current printed layer.

[0126] Item 10, according to the stereolithography method in Item 5, wherein controlling the curing unit to irradiate the pigment layer specifically includes:

[0127] The curing unit is controlled to irradiate the pigment according to the contour of the current printed layer;

[0128] Alternatively, the curing unit can be controlled to irradiate the pigment according to its outline;

[0129] Alternatively, the curing unit can be controlled to irradiate the pigment according to a preset outline with a coverage area larger than the pigment outline.

[0130] Alternatively, the curing unit can be controlled to move and irradiate the pigment.

[0131] Serial number 11, according to the stereolithography method of serial number 6, wherein the stereolithography equipment further includes a material tank, the material tank includes a receiving cavity, the material tank further includes a release film, the release film is part of the wall of the receiving cavity, and the release film is a construction window; the feeding and discharging assembly is connected to the receiving cavity, and the step of controlling the feeding and discharging assembly to add printing material to the construction window specifically includes:

[0132] The feeding and discharging components are controlled to add a preset amount of printing material into the receiving cavity of the material trough;

[0133] Alternatively, the feeding and discharging components can be controlled to add printing material into the receiving cavity of the material trough within a preset time.

[0134] Alternatively, the stereolithography equipment may also include a liquid level sensor, which is positioned opposite the receiving cavity, and a step that controls the feeding and discharging components to add printing material to the build window, specifically including:

[0135] The feeding and discharging components are controlled to continuously add printing material into the receiving cavity;

[0136] Receive the liquid level height of the printing material from the liquid level sensor;

[0137] If the liquid level reaches the preset liquid level, the feeding and discharging components will stop adding printing material into the receiving cavity of the material tank.

[0138] Alternatively, the stereolithography equipment may also include a weight sensor connected to a material trough, which controls the feeding and discharging components to add printing material to the build window, specifically including:

[0139] The feeding and discharging components are controlled to continuously add printing material into the receiving cavity;

[0140] Receive weight values ​​sent by the weight sensor;

[0141] If the weight reaches the preset weight, the feeding and discharging components will stop adding printing material into the material trough's receiving cavity.

[0142] Serial number 12, according to the three-dimensional forming method in serial number 2, wherein,

[0143] The distance between the printing platform and the build window is the sum of the thickness of the pre-built model connected to the printing platform and the thickness of the single-layer model.

[0144] Serial number 13, according to the stereolithography method of serial number 1, wherein after controlling the printing platform to approach the construction window so that the pigment layer is cured on the current printing layer, the method further includes:

[0145] Repeat the following steps: First, take the layer below the current printed layer as the current printed layer. Then, control the printing platform to move to the release height so that the current printed layer carries the pigment layer away from the build window. Next, add printing material to the build window, with the material's coverage area corresponding to the current printed layer of the model to be printed. Then, move the printing platform closer to the build window to print the current printed layer of the model on the printing platform. Finally, move the printing platform away from the build window and remove the printing material from the build window to spray a pigment layer onto the build window, corresponding to the current printed layer. Next, move the printing platform closer to the build window to allow the pigment layer to solidify on the current printed layer. Continue this process until the model to be printed is complete.

[0146] Serial number 14, according to the three-dimensional forming method of serial number 1, wherein controlling the printing platform away from the build window includes:

[0147] Control the printing platform to move away from the build window to a preset height, which is the sum of the base height and the thickness of the formed model connected to the printing platform.

[0148] Serial number 15, according to the stereolithography method of serial number 1, wherein the stereolithography equipment includes an infeed / outfeed assembly, and removes printing material from the building window, including:

[0149] The feed and discharge components control the discharge of printing material from the build window.

[0150] Serial number 16, according to the stereolithography method of serial number 15, wherein the stereolithography equipment further includes a scraper unit; after the step of controlling the feeding and discharging components to discharge the printing material on the building window, the method further includes:

[0151] Control the scraper unit to scrape off the printing material above the build window.

[0152] Serial number 17, according to the stereolithography method of serial number 16, wherein the scraper unit includes a scraper and a flipping drive, the scraper is connected to the flipping drive, and the scraper position includes a scraping push position and a retracting position. In the scraping push position, the bottom end of the scraper is closer to the building window than the bottom end of the scraper in the retracting position; controlling the scraper unit to scrape off the printing material above the building window includes:

[0153] Control the tilting drive to move the scraper to the scraping position;

[0154] Control the scraper's movement to scrape away the printed material above the build window;

[0155] Control the flip drive to move the scraper to the storage position.

[0156] Serial number 18, according to the stereolithography method in serial number 4, the stereolithography equipment further includes a curing unit.

[0157] The curing unit includes a single curing element located on one side of the printing platform opposite to the build window. The curing element is used to irradiate the pigment layer and also to irradiate the printing material to form the current printing layer.

[0158] Alternatively, the curing unit includes a first curing element and a second curing element. The first curing element is located on the side of the build window closer to the printing platform and is used to irradiate the pigment layer. The second curing element is located on the side of the build window opposite to the printing platform and is used to irradiate the printing material to form the current printed layer and to irradiate the pigment layer so that the pigment layer is cured on the current printed layer.

[0159] Serial number 19, according to the stereolithography method of serial number 5, wherein before spraying a layer of pigment onto the construction window, the method further includes:

[0160] Get the color information corresponding to the current printing layer;

[0161] Use one of the multiple printing layers as the current printing layer;

[0162] Control the printing platform to move to the initial position.

[0163] Serial number 20, a three-dimensional forming device, comprising:

[0164] Memory, used to store computer programs;

[0165] A processor is used to execute computer programs to implement the steps of a stereolithography method as described in any of numbers 1 to 19.

[0166] Serial number 21, a computer-readable storage medium, wherein the computer-readable storage medium stores at least one executable instruction, the executable instruction causing a processor to perform the steps of the stereolithography method as described in any one of serial numbers 1 to 19.

[0167] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A three-dimensional forming method, characterized in that, A stereolithography method is applied to a stereolithography apparatus for printing a model to be printed, the stereolithography apparatus including a building window and a printing platform, the stereolithography method comprising: Add printing material to the build window. The printing material is located at the position covered by the build window and corresponds to the current printing layer of the model to be printed. The printing material is a light-transmitting printing material. The printing platform is brought close to the build window so that the printing material is solidified on the printing platform to form the current printing layer of the model to be printed. The printing platform is moved away from the build window, and the printing material on the build window is removed, so as to spray a layer of pigment onto the build window, the pigment layer corresponding to the current printing layer; The printing platform is brought closer to the build window so that the pigment layer is cured onto the current printing layer.

2. The three-dimensional forming method according to claim 1, characterized in that, The step of controlling the printing platform to move closer to the build window so that the printing material is cured on the printing platform to form the current printing layer of the model to be printed includes: The printing platform is controlled to move closer to the build window so that the distance between the printing platform and the build window corresponds to the distance required for the current printing layer of the model to be printed; According to the contour information of the current printing layer, the curing light is controlled to irradiate the printing material to form the current printing layer of the model to be printed on the surface of the printing platform or on the completed model of the model to be printed on the printing platform.

3. The three-dimensional forming method according to claim 1, characterized in that, The control of the printing platform to move closer to the build window so that the pigment layer is cured on the current printing layer includes: Control the printing platform to move closer to the build window, with the distance between the printing platform and the build window being a preset distance; or, The printing platform is controlled to move closer to the build window, and the distance between the printing platform and the build window corresponds to the distance required for the current printing layer of the model to be printed.

4. The three-dimensional forming method according to claim 1, characterized in that, The stereolithography equipment further includes a curing unit, and the method further includes, simultaneously or after, spraying a layer of pigment onto the construction window: The curing unit is controlled to irradiate the pigment layer so that the surface of the pigment layer in contact with the build window is cured, while at least a portion of the surface of the pigment layer away from the build window remains uncured.

5. The three-dimensional forming method according to claim 1, characterized in that, The process of spraying a layer of pigment onto the construction window includes: According to the color information of the current printing layer, a layer of pigment is sprayed onto the construction window.

6. The three-dimensional forming method according to claim 1, characterized in that, The stereolithography equipment includes an infeed / outfeed assembly, and the step of adding printing material to the building window includes: The feeding / discharging assembly is controlled to add printing material to the build window, wherein the thickness of the printing material is greater than or equal to the thickness of the current printing layer.

7. The three-dimensional forming method according to claim 5, characterized in that, The stereolithography equipment further includes a nozzle unit and a curing unit. Specifically, spraying a pigment layer onto the construction window according to the color information of the current printing layer includes: The nozzle unit is controlled to spray pigment onto the build window according to the color information of the current printing layer to form a pigment layer.

8. The three-dimensional forming method according to claim 7, characterized in that, The color information of the current printed layer includes a spraying area, the spraying area includes at least one sub-spraying area, and the color information of the current printed layer also includes color information corresponding to the sub-spraying area. The control nozzle unit sprays pigment onto the construction window according to the color information of the current printed layer, specifically including: The nozzle unit is controlled to spray pigment onto the construction window according to the sub-spraying area and the color information.

9. The three-dimensional forming method according to claim 8, characterized in that, The outline of the sprayed area is consistent with the outline of the current printed layer; Alternatively, a portion of the outline of the sub-spraying area may coincide with a portion of the outline of the current printed layer; Alternatively, the spraying area may be a region of a preset width that matches the contour of the current printed layer.

10. The three-dimensional forming method according to claim 4, characterized in that, The control of the curing unit to irradiate the pigment layer specifically includes: The curing unit is controlled to irradiate the pigment according to the contour of the current printed layer; Alternatively, the curing unit can be controlled to irradiate the pigment according to the outline of the pigment; Alternatively, the curing unit can be controlled to irradiate the pigment according to a preset outline with a coverage area larger than the pigment outline; Alternatively, the curing unit can be controlled to move and irradiate the pigment.

11. The three-dimensional forming method according to claim 6, characterized in that, The stereolithography equipment further includes a material tank, which includes a receiving cavity and a release film. The release film is part of the wall of the receiving cavity and serves as the construction window. The feeding / discharging assembly communicates with the receiving cavity. The step of controlling the feeding / discharging assembly to add printing material to the construction window specifically includes: The feeding and discharging components are controlled to add a preset amount of printing material into the receiving cavity of the material trough; Alternatively, the feeding and discharging components can be controlled to add printing material into the receiving cavity of the material trough within a preset time period; Alternatively, the stereolithography apparatus may further include a liquid level sensor, which is opposite to the receiving cavity, and the step of controlling the feeding / discharging assembly to add printing material to the building window specifically includes: The feeding and discharging assembly is controlled to continuously add printing material into the receiving cavity; Receive the liquid level height of the printing material from the liquid level sensor; If the liquid level reaches the preset liquid level, the feeding and discharging components are controlled to stop adding printing material into the receiving cavity of the material tank; Alternatively, the stereolithography equipment may further include a weight sensor connected to the material trough, wherein the step of controlling the feeding / discharging assembly to add printing material to the building window specifically includes: The feeding and discharging assembly is controlled to continuously add printing material into the receiving cavity; Receive weight values ​​sent by the weight sensor; If the weight value reaches the preset weight, the feeding and discharging components are controlled to stop adding printing material into the receiving cavity of the material tank.

12. The three-dimensional forming method according to claim 2, characterized in that, The distance between the printing platform and the construction window is the sum of the thickness of the pre-formed model connected to the printing platform and the thickness of the single-layer model.

13. The three-dimensional forming method according to claim 1, characterized in that, After controlling the printing platform to move closer to the build window so that the pigment layer is cured on the current printed layer, the method further includes: Repeat the following steps: First, take the layer below the current printed layer as the current printed layer. Second, control the printing platform to move to the release height so that the current printed layer pulls the pigment layer away from the build window. Third, add printing material to the build window, the location of which corresponds to the current printed layer of the model to be printed. Fourth, control the printing platform to move closer to the build window to print the current printed layer of the model to be printed on the printing platform. Fifth, control the printing platform to move away from the build window and remove the printing material from the build window to spray a pigment layer onto the build window, the pigment layer corresponding to the current printed layer. Sixth, control the printing platform to move closer to the build window to solidify the pigment layer on the current printed layer, until the printing of the model to be printed is completed.

14. The three-dimensional forming method according to claim 1, characterized in that, The control of the printing platform away from the build window includes: Control the printing platform to move away from the build window to a preset height, where the preset height is the sum of the base height and the thickness of the formed model connected to the printing platform.

15. The three-dimensional forming method according to claim 1, characterized in that, The stereolithography equipment includes an infeed / outfeed assembly, and the step of removing printing material from the build window includes: The feeding and discharging components are controlled to discharge the printing material from the build window.

16. The three-dimensional forming method according to claim 15, characterized in that, The stereolithography equipment further includes a scraper unit; after the step of controlling the feeding and discharging assembly to discharge the printing material on the build window, the method further includes: The scraper unit is controlled to scrape off the printing material above the build window.

17. The three-dimensional forming method according to claim 16, characterized in that, The scraper unit includes a scraper and a flipping drive. The scraper is connected to the flipping drive. The scraper has a scraping and pushing position and a retracting position. In the scraping and pushing position, the bottom end of the scraper is closer to the construction window than the bottom end of the scraper in the retracting position. The control scraper unit scrapes away the printing material above the build window, including: The flipping drive is controlled to move the scraper to the scraping position; Control the movement of the scraper to scrape away the printing material above the build window; Control the flipping drive to move the scraper to the storage position.

18. The three-dimensional forming method according to claim 4, characterized in that, The stereolithography equipment also includes a curing unit. The curing unit includes a single curing element located on the side of the build window opposite to the printing platform. The curing element is used to irradiate the pigment layer and also to irradiate the printing material to form the current printed layer. Alternatively, the curing unit includes a first curing element and a second curing element. The first curing element is located on the side of the build window near the printing platform and is used to irradiate the pigment layer. The second curing element is located on the side of the build window opposite the printing platform and is used to irradiate the printing material to form the current printed layer and to irradiate the pigment layer so that the pigment layer is cured on the current printed layer.

19. The three-dimensional forming method according to claim 5, characterized in that, Before spraying a layer of pigment onto the construction window, the method further includes: Obtain the color information corresponding to the current printing layer; The current printing layer is one of multiple printing layers. Control the printing platform to move to the initial position.

20. A three-dimensional forming device, characterized in that, include: Memory, used to store computer programs; A processor, configured to implement the steps of the stereolithography method as described in any one of claims 1 to 19 when executing the computer program.

21. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one executable instruction that causes a processor to perform the steps of the stereolithography method as described in any one of claims 1 to 19.

Images