CN112109321A

CN112109321A - Photocuring 3D printing device

Info

Publication number: CN112109321A
Application number: CN201910531575.9A
Authority: CN
Inventors: 黄鹤源; 蔡德信; 刘青山; 邢永锋; 王淼; 桂培炎
Original assignee: Guangzhou Him3d Information Technology Co ltd
Current assignee: Guangzhou Him3d Information Technology Co ltd
Priority date: 2019-06-19
Filing date: 2019-06-19
Publication date: 2020-12-22

Abstract

The invention discloses a photocuring 3D printing device. The 3D printing device comprises a material tray, a forming platform, a lifting mechanism, a light source device, a material box and a material mixing device; the material tray is used for bearing photosensitive resin; the forming platform is provided with a forming end face, and the forming end face is used for bearing a 3D printing product; the lifting mechanism is used for driving the forming platform to move; the projection direction of the light emitted by the light source device is right opposite to the molding end face; the material box is filled with different photosensitive resins; the mixing device is connected with the material box and is provided with a feeding pipe communicated with the material tray, wherein the photosensitive resin in the material box can be mixed in the mixing device to form mixed resin with specific color and/or specific mechanical property and/or specific solubility. The technical scheme of the invention can realize the color printing effect, or realize that different positions of a printed product have different mechanical properties or dissolubility, and the structure is simple.

Description

Photocuring 3D printing device

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to a photocuring 3D printing device.

Background

3D color printing is one of the developing directions in the field of 3D printing. In the current 3D Printing industry, Three Dimensional spray painting and blending (3 DP) is capable of color Printing, but it uses powder material forming, in which the powder is used to "print" the cross section of the part on the material powder by means of a spray head and a binder (such as silica gel). However, parts bonded with adhesives have low strength, require subsequent processing, and have rough molding surfaces.

Different from the three-dimensional spray bonding forming technology, the printing speed of a stereolithography application (SLA) printer is high, the forming precision is high, and the printed product can be comparable to the injection-molded durable plastic part in the aspects of material properties, details, surface finish and the like. However, currently, the photo-curing molding printing apparatus can print only one material at a time, and can print only a single color.

Patent document CN207273884U discloses a sample injector type photo-curing 3D printing apparatus, which is provided with a liquid changing device, and can make the same mold be made of materials with different performances by the liquid changing device, so as to meet the requirement of multi-color printing to some extent. However, when this technique is used to print products having a plurality of colors, it is necessary to prepare and adjust the printing material tanks, the printing material injectors, and the number and kinds of the three materials according to the specific colors. This makes the structure of the 3D printer very complicated.

Patent document CN109414307A discloses a method of manufacturing a dental prosthesis by continuously changing the composition of the resin during printing, thereby achieving that the surface optical properties of the dental prosthesis vary in a gradual manner in the vertical direction. However, the technology can only realize the color gradient effect of the printed product, and cannot realize the color effect of any color superposition, so that the technology still has certain limitation on the application of color printing.

Patent document CN105500700A discloses a color three-dimensional printing apparatus and method that adds a DLP projector for further enhancing curing compared to an SLA printing apparatus. Specifically, according to the technical scheme, the photosensitive resin is sprayed out by the spray head, the photosensitive resin material is irradiated to a semi-curing state by the ultraviolet point light source, and then the photosensitive resin material is further cured by the DLP projection system, so that the processing time is increased undoubtedly by the operation of twice curing; a nozzle type printing method is adopted, and a moving mechanism with a complex structure is usually required to be carried to form a large-format product; the forming working pool (namely a material tray) inevitably has a pollution problem because the color of the resin needs to be changed frequently; frequently moving the spray head and changing the position of the forming platform not only complicates the operation but also affects the position accuracy.

In addition to the need for color printing, it is sometimes necessary to have different mechanical properties or solubility at different locations of the printed product, but none of the above needs can be effectively met by using a photo-curing 3D printing process.

Disclosure of Invention

The invention mainly aims to provide a photocuring 3D printing device which can realize color printing or realize that different positions of a printed product have different mechanical properties or dissolubility and has a simple structure.

According to an aspect of an embodiment of the present invention, there is provided a photocuring 3D printing apparatus, the 3D printing apparatus including:

the material tray is used for bearing photosensitive resin;

the forming platform is provided with a forming end face, and the forming end face is used for bearing a 3D printing product;

the lifting mechanism is used for driving the forming platform to move;

a light source device, wherein the projection direction of the light emitted by the light source device is right opposite to the molding end surface;

a plurality of material cartridges containing different photosensitive resins;

and the material mixing device is connected with the material box and is provided with a feeding pipe communicated with the material tray, wherein the photosensitive resin in the material box can be mixed in the material mixing device to form mixed resin with a specific color and/or specific mechanical property and/or specific solubility.

According to the technical scheme, the 3D printing device obtains the resin with the specific color, the specific mechanical property or the specific solubility by mixing before the printing process, so that the printing effect with the expected color, the expected mechanical property or the expected solubility can be realized, the problems that the photocuring 3D printing process is difficult to realize color printing and different positions of a printed product have different mechanical properties or solubilities are overcome, and the structure is simple.

Further, a flow control module is further arranged between the material box and the mixing device, and the flow control module comprises a control valve and a flow meter. The flow meter is used for measuring the amount of the resin material conveyed from a certain material box to the mixing device, and the control valve is used for controlling the communication and the closing between the material box and the mixing device according to the numerical value measured by the flow meter. The flow meter and the control valve are matched for use, so that the proportion of each resin material can be controlled during mixing.

Furthermore, a feeding pump is arranged in the feeding pipe and is respectively communicated with the material mixing device and the material tray through the feeding pipe. The feeding pump can enable the mixed resin liquid to flow more smoothly, so that the mixed resin liquid can reach the material tray as soon as possible, and the mixed resin liquid residue adhered to the inner wall of the feeding pipe is reduced.

Further, the mixing device is also provided with a stirrer, a stirring structure is arranged in the stirrer, and the stirring structure extends into the mixing device. The stirrer is arranged to help fully mix different photosensitive resin liquids, so that ideal color, mechanical property or solubility can be obtained.

Further, the mixing device is also connected with a cleaner, and the cleaner is used for removing residual materials in the mixing device. And residual materials in the mixing device are removed, so that the pollution on color, the deviation on mechanical property or the deviation on solubility caused by residual photosensitive resin liquid can be avoided.

Further, the cleaner can convey volatile cleaning liquid to the mixing device. The cleaning liquid is easy to volatilize, and the resin material can be prevented from being polluted by the residual cleaning liquid.

Further, the mixing device is also provided with a heating device. Heating device can accelerate the vaporization of washing liquid to can improve the mobility of resin, make the mixture of resin more even, in addition, heating device does benefit to the partly bubble that produces among the discharge stirring resin process.

Further, photocuring 3D printing device still includes removes the material scraper, remove the material scraper and be used for scraping away uncured defective material in the charging tray, remove the material scraper and can do planar motion. The material removing scraper scrapes uncured residual materials in the material tray, and the pollution on the color caused by the residual photosensitive resin liquid can be avoided.

Further, photocuring 3D printing device still includes the stone scraper, the stone scraper can be planar motion. The spreading scraper is used for avoiding the problem of uneven distribution of photosensitive resin in a charging tray caused by poor flowability of the photosensitive resin.

Further, a residual material collecting tank is arranged at the bottom of the material tray and communicated with a waste material pipeline. The residual material collecting tank is communicated with the waste pipeline, so that the residual materials are more convenient to collect and print.

Further, the feeding pipe is arranged in front of the plane movement of the spreading scraper in the advancing direction. The mutual position relation of conveying pipe and stone scraper so sets up, can obtain reasonable pay-off and stone order: feeding is performed first, and spreading is performed later.

Further, the photocuring 3D printing device further comprises a material removing scraper, wherein the material removing scraper is used for scraping uncured residual materials in the material tray and can perform planar motion; compared to the spreading scraper, the material removal scraper is behind the spreading scraper in the forward direction of the planar movement. The mutual position relation of the material removing scraper and the spreading scraper is set up in such a way, and the reasonable material removing and spreading sequence is obtained: the paving is performed first and the material removal is performed later.

Further, the photocuring 3D printing device further comprises a material removing scraper, wherein the material removing scraper is used for scraping uncured residual materials in the material tray and can perform planar motion; the photocuring 3D printing device further comprises a spreading scraper, and the spreading scraper can do planar motion; the spreading scraper, the feeding pipe and the material removing scraper are formed into an integral structure, so that the material removing process and the spreading process can be almost simultaneously carried out.

Further, a liquid outlet is formed in one end, close to the material tray, of the spreading scraper, and the liquid outlet is used for flowing out of the photosensitive resin liquid. One end of the spreading scraper is provided with a liquid outlet which can be used as a feeding pipe, so that the spreading scraper and the feeding pipe are integrated, and the purpose of pouring and spreading materials is realized.

Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic structural diagram of a 3D printing apparatus according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention;

FIG. 3 is a view showing some variations of the connection among the feeding pipe, the material removing blade and the spreading blade in the embodiment of FIG. 2;

fig. 4 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention;

fig. 5 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention;

FIG. 6 is a schematic structural view of a mixing apparatus according to yet another embodiment of the present invention;

fig. 7 is a schematic structural diagram of a flow control module in the embodiment shown in fig. 6.

Reference numerals: in the figure, 110-ray machine; 120-material tray; 121-a residue collecting tank; 130-a forming platform; 140-a lifting mechanism; 150-a mixing device; 151-a feed pipe; 152-a stirrer; 160-material cartridge; 170-material removal scraper; 180-a waste collection device; 181-waste conduit; 182-waste bin;

210-an optical machine; 220-material tray; 221-a residue collecting tank; 230-a forming platform; 240-a lifting mechanism; 250-a mixing device; 251-a feed tube; 252-a stirrer; 253-a cleaner; 160-material cartridge; 270-a material removing scraper; 280-a waste collection device; 281-a waste conduit; 282-waste bin; 290-spreading scraper;

320-material tray; 351-a feeding pipe; 370-a material removal scraper; 390-spreading scraper; 391-liquid outlet;

410-an optical machine; 420-material tray; 430-a forming platform; 440-a lifting mechanism; 450-a mixing device; 451-a feeding pipe; 452-a stirrer; 460-a material cartridge; 480-a waste collection device; 481 — waste line; 482-scrap box; 491-a scraper plate;

510-a laser; 520-a tray; 530-a forming table; 540-a lifting mechanism; 550-a mixing device; 551-a feeding pipe; 552-a stirrer; 560-a material cartridge; 580-a waste collection device; 581-waste pipe; 582-a waste bin; 591-scraper blade.

650-a mixing device; 651-feed tube; 652-stirrer; 654-flow control module; 6541-control valve; 6542-flow meter; 655-a heating device; 660-material cartridge.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the term "connected" is to be interpreted broadly, and may be, for example, a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship.

DLP (Digital Light Processing) means that Light is projected after image signals are digitally processed.

The technical principle of the traditional DLP photocuring printing process flow is briefly introduced as follows:

the method comprises the following steps of 3D modeling: designing a three-dimensional solid model of a product, and slicing the model through software to obtain data of the shape of a light spot;

and placing the photosensitive resin liquid into a tray, wherein the photosensitive resin liquid is quickly cured under the irradiation of a light source, so that a solid product is formed. Taking the lifting type DLP 3D printing device as an example, the forming platform is arranged above the material tray, and the forming end surface of the material tray can be contacted with the photosensitive resin liquid;

and the light machine emits light spot shapes with corresponding shapes according to the data processed by slicing, so that the layer of resin is cured. Taking the above-mentioned 3D printing device of rising DLP as an example, after the layer is printed, the forming platform is driven by the lifting mechanism to move upward for a certain distance (for the 3D printing device of sinking DLP, the forming platform moves downward for a certain distance). Subsequently, on the basis of the photosensitive resin of the upper layer cured, the shape of the next layer is printed. And (5) superposing layer by layer to obtain the required 3D printing product.

As can be known from the introduction of the technical principle, the traditional DLP photocuring printing device can only print one color and cannot meet the requirement of color printing.

The following text will describe a 3D printing apparatus in some embodiments of the invention with reference to the drawings of the specification.

Fig. 1 is a schematic structural diagram of a 3D printing apparatus according to an embodiment of the present invention. Specifically, the printing apparatus in fig. 1 is a 3D printing apparatus of an ascending DLP. As shown in fig. 1, the 3D printing apparatus includes an optical machine 110, a tray 120, a forming platform 130, a lifting mechanism 140, a mixing device 150, a material box 160, a material removing scraper 170, and a waste collecting device 180, wherein the optical machine 110 is located at the lowest position, the tray 120 is located above the optical machine 110, the forming platform 130 is located above the tray 120, and the lifting mechanism 140 is connected to the upper end of the forming platform 130. The forming platform 130 can be driven to move horizontally in the up-down direction by the up-down translational movement of the lifting mechanism 140.

The optical engine 110 is a light source device, and the light emitted by the optical engine 110 can cure the photosensitive resin liquid, and the projection direction of the light emitted by the optical engine 110 is aligned with the bottom surface of the forming platform 130.

The tray 120 is used for carrying the photosensitive resin liquid, and the tray 120 is located between the optical machine 110 and the forming platform 130 in the vertical direction. The bottom surface of the tray 120 allows light to pass through, so that the light emitted by the optical engine 110 can pass through the bottom surface of the tray 120. Preferably, the bottom of the tray 120 is made of transparent material such as glass or acrylic.

The bottom surface of the molding platform 130 is a molding end surface for carrying the photosensitive resin that has been cured, which is laminated to form a 3D printed product. The shaped end face is aligned with the projection direction of the light emitted by the light engine 110.

The lifting mechanism 140 is used to drive the forming platform 130 to move along the printing direction. The printing directions of the 3D printing device of the rising DLP and the 3D printing device of the sinking DLP are both the up-down direction. Preferably, the lower end of the lifting mechanism 140 is connected with the forming platform 130.

The material cartridge 160 is plural in number. By "plurality" is meant at least two. In the embodiment shown in fig. 1, there are three material cartridges 160. The material cartridge 160 contains different photosensitive resins.

The mixing device 150 may be considered a container and the mixing device 150 is connected to the material cartridge 160.

Different photosensitive resins refer to different colors or different optical properties such that different photosensitive resins are recognized as having different colors by human eyes.

In addition to being resins of different colors, it is also possible to have resins with different mechanical properties (for example hardness) or with different solubility:

(1) have different mechanical properties: on one hand, the printing of different structures by adopting resins with different hardness can be realized, for example, a printed piece adopts conventional resin according to the use requirement, and the supporting structure adopts relatively hard resin material for printing; on the other hand, the effect that the printed matter has different mechanical properties at different parts can be realized, and the effect similar to color printing can be realized; on the other hand, the function of the printing device is more diversified and more intelligent, and the proportion of soft resin and hard resin can be adjusted by a user according to the requirement of the final finished product on the hardness or toughness of the material.

The functions can break the limitation of 3D printing piece design and expand the application of the 3D printing piece.

It is understood that "mechanical properties" in this disclosure are also referred to as mechanical properties, including but not limited to: strength, plasticity, hardness, impact toughness, multiple impact resistance and fatigue limit;

(2) resins with different solubilities: the support structure may be a material that is readily soluble in a solvent.

In the embodiment shown in fig. 1, for example, to realize the color printing effect, three material cartridges 160 are connected to the mixing device 150 such that three photosensitive resins from the three material cartridges 160 are collected into the mixing device 150. The above three photosensitive resins are mixed in the mixing device 150 to be a mixed resin having a specific color. The color of the material in the material cartridge 160 may be determined according to the particular use case. Preferably, the material cartridge 160 contains photosensitive resins corresponding to three primary colors of red, yellow and blue, respectively.

The mixing device 150 is provided with a feed pipe 151 communicating with the tray 120 so that the mixed resin having a specific color in the mixing device 150 reaches the tray 120 through the feed pipe 151. Preferably, the mixing device 150 is located between the material box 160 and the material tray 120 in the up-down direction, the material box 160 is located above, the feeding pipe 151 is arranged at the bottom of the mixing device 150, and the feeding pipe 151 is communicated with the material tray 120 below. The photosensitive resin from the material cartridge 160 is mixed by gravity and can smoothly reach the tray 120.

More preferably, a feeding pump (not shown) may be disposed in the feeding pipe 151, that is, the feeding pump is respectively communicated with the mixing device 150 and the tray 120 through the feeding pipe 151. The feed pump may pump the mixed resin in the mixing device 150 into the tray 120. Without the aid of gravity (e.g., the tray is not located below the feed tube), the feed pump is still able to efficiently feed the mixed resin into the tray 120; in the case of using the gravity (for example, the tray is located below the feeding pipe), the feeding pump can make the flow of the mixed resin smoother. The feed pump can be a peristaltic pump.

The mixing device 150 is also provided with a stirrer 152, and the stirrer 152 has a stirring structure. The stirring structure can be a stirring rod. The stirring rod extends into the interior of the mixing device 150. The shape of the stirring rod can be selected and determined according to the needs. Preferably, the stirring rod is a worm that can be driven by a motor or the like so that the worm is driven to sufficiently stir the photosensitive resin in the mixing device 150.

The stripper blade 170 is located above the tray 120 and below the forming table 130 in a vertical mutual positional relationship. The stripper blade 170 is used to scrape away the uncured residue in the tray 120. The stripper blade 170 may move in a planar manner. The planar movement means that the distance from the bottom end of the scraper to the surface of the resin material is almost constant, and includes translation in the length direction of the tray, or translation in the width direction of the tray, or rotation. The rotation includes a fixed axis rotation and a non-fixed axis rotation, and the non-fixed axis rotation includes a rotation while moving. The length of the scraper 170 is equal to the width of the tray 120, so as to ensure that the scraper 170 can completely scrape the residual material while moving horizontally along the length direction of the tray 120.

The scrap collecting device 180 is communicated with the tray 120 and is used for collecting the residual scraps in the tray 120. The waste collection device 180 includes a waste conduit 181 and a waste bin 182. The waste bin 182 is used to hold the remainder of the printing. The waste bin 182 communicates with the tray 120 via a waste conduit 181. Preferably, the waste conduit 181 is located below one side of the tray 120 and the waste bin 182 is located below the waste conduit 181. A suction pump is provided in the waste pipe 181 to accelerate the recovery rate of the waste. A residual material collecting groove 121 is arranged at the bottom of the material tray 120 close to the edge. The residue collecting tank 121 is communicated with a waste pipeline 181, and the waste pipeline 181 is positioned below the residue collecting tank 121. The cull removal scraper 170 may push the cull into the cull collection tank 121. The residue collection groove 121 is a through hole, which should be understood as a groove in a broad sense, i.e. including a groove with a circular, square or elongated cross section. Structures in the form of through-holes or blind holes are understood to be a particular form of residue collection chute 121.

The process flow and the working principle of the 3D printing apparatus shown in fig. 1 are summarized as follows:

modeling a product, and designing a three-dimensional model of the product; carrying out slicing and layering processing on the product model to obtain shape data, layer thickness data and color data corresponding to each layer;

mixing by a mixing device 150 to obtain photosensitive resin with a specific color, and pouring the photosensitive resin into a tray 120;

the forming platform 130 descends, the optical machine 110 projects the light spot shape, and a layer of cured sheet is generated on the forming platform 130;

after printing one layer, the forming platform 130 is raised, and the material removing scraper 170 scrapes away uncured residual resin;

new resin is laid down and the printing step is repeated.

The 3D printing device shown in FIG. 1 overcomes the difficulty that the photocuring 3D printing process is difficult to realize color printing, and has a simple structure. Different from the existing technical scheme (the proportion of the photosensitive resin liquid of a certain color is continuously adjusted in the printing process, and only the gradual-change printing effect can be realized), the 3D printing device in the technical scheme in the embodiment mixes the resin of a specific color before the printing process, so that the printing effect of any specific color can be realized. In addition, the 3D printing device shown in fig. 1 adopts the material removal scraper to remove the residual material left in the previous printing, so that the residual material can be prevented from polluting the resin material printed in the subsequent printing.

Fig. 2 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention. The 3D printing device in the technical scheme of the embodiment shown in FIG. 2 is additionally provided with a spreading blade and a cleaner on the basis of FIG. 1.

As shown in fig. 2, the 3D printing apparatus includes a polishing machine 210, a tray 220, a forming platform 230, a lifting mechanism 240, a mixing device 250, a material box 260, a material removing scraper 270, a waste collecting device 280, and a spreading scraper 290, wherein the tray 220 is provided with a residue collecting tank 221, the mixing device 250 includes a feeding pipe 251 and an agitator 252, and the waste collecting device 280 includes a waste pipe 281 and a waste bin 282. The connection relationship, the mutual position relationship and the effect of the above components are the same as the technical solution of the embodiment shown in fig. 1, and are not described herein again.

Fig. 2 shows that the 3D printing apparatus further includes a cleaner 253, and the cleaner 253 is in communication with the mixing apparatus 250. Preferably, the cleaner 253 and the material cartridge 260 are both located above the mixing device 250. The mixing device 250 inevitably has a pollution problem due to the frequent color mixing, and the cleaner is especially necessary. Specifically, the cleaner 253 may deliver a cleaning liquid to the mixing device 250 to clean the mixing device 250. The agitator 252 may be simultaneously activated during the cleaning process to facilitate the flow of cleaning fluid for the rinsing function.

In order to avoid contamination of the resin material by residual cleaning liquid, the cleaning liquid may be selected from volatile cleaning liquids such as ethanol, isopropanol or acetone.

A heating device can be added to the mixing device 250 to accelerate the vaporization of the cleaning liquid. In addition, the addition of the heating device can also improve the flowability of the resin, so that the resin is mixed more uniformly, and a part of bubbles generated in the resin stirring process can be discharged.

As also shown in fig. 2, the 3D printing device further comprises a spreading blade 290. In a mutual positional relationship in the up-down direction, both the spreading blade 290 and the material-removing blade 270 are located above the tray 220 and below the forming table 230. The spreading blade 290 may make a planar movement. The planar movement means that the distance from the bottom end of the scraper to the surface of the resin material is almost constant, and includes translation in the length direction of the tray, or translation in the width direction of the tray, or rotation. The rotation includes a fixed axis rotation and a non-fixed axis rotation, and the non-fixed axis rotation includes a rotation while moving.

Optionally, the length of the spreading blade 290 is equivalent to the width of the tray 220, so as to ensure that the photosensitive resin can be spread over the entire tray 220 under the condition that the spreading blade 290 is translated along the length direction of the tray 220.

In the process of pouring the photosensitive resin into the feeding pipe 251, the photosensitive resin in the tray 220 is unevenly distributed due to poor flowability of the photosensitive resin, and the quality of 3D printing is affected. The spreading blade 290 can overcome the problem of poor fluidity of the photosensitive resin so that the photosensitive resin spreads over the tray 220.

The process flow and the working principle of the 3D printing apparatus shown in fig. 2 are summarized as follows:

photosensitive resin with a specific color is obtained by mixing through the mixing device 250, the photosensitive resin is poured into the material tray 220, and the photosensitive resin is uniformly paved in the material tray 220 by the paving scraper 290;

the forming platform 230 descends, the light machine 210 projects a light spot shape, and a layer of cured sheet is generated on the forming platform 230;

after printing one layer, the forming platform 230 is raised, and the material removing scraper 270 scrapes away uncured residual resin;

new resin is laid down and the printing step is repeated.

The mixing device 250 may be cleaned between printings.

The 3D printing device in the technical solution of the embodiment shown in fig. 2 not only realizes the 3D color printing effect of photocuring molding, but also has the following advantages: spreading by adopting a spreading scraper, so that the photosensitive resin can be fully spread in the whole material tray; adopt the cleaner to wash the compounding device, further avoided the color pollution problem that the defective material arouses.

Fig. 3 shows some modified examples of the connection relationship among the feeding pipe, the material removing blade and the spreading blade in the embodiment shown in fig. 2.

As shown in fig. 3(a), the spreading blade 390 has a liquid outlet 391 at an end near the tray 320, and the liquid outlet 391 is used for flowing out the photosensitive resin liquid. The spreading scraper 390 is coaxial with the feeding pipe 351, and the spreading scraper 390 is located right below the feeding pipe 351, so that the photosensitive resin liquid sequentially passes through the feeding pipe 351 and the body of the spreading scraper 390, and finally flows out from the liquid outlet 391 of the spreading scraper 390. The side of the advancing direction of the paving scraper 390 is used as the front, the material removing scraper 370 is located behind the feeding pipe 351 and the paving scraper 390, and the material removing scraper 370 and the feeding pipe 351 are separated by a certain distance in the advancing direction of the paving scraper 390, so that the material removing process is performed after the paving process, and the problem of residual material pollution caused by reverse operation is avoided.

As shown in fig. 3(b), the spreading blade 390 is located in front of the feeding pipe 351 with the side of the spreading blade 390 in the forward direction as the front, the material removing blade 370 is located behind the feeding pipe 351, and the material removing blade 370 and the feeding pipe 351 are spaced apart from each other by a certain distance in the forward direction of the spreading blade 390. By the arrangement, the problem of residual material pollution is also avoided.

As shown in fig. 3(c), the spreading blade 390 is located in front of the feeding pipe 351, and the material removing blade 370 is located behind the feeding pipe 351, with the advancing direction of the spreading blade 390 being the front, and two of the three are in contact with each other without a space. By the arrangement, the problem of residual material pollution is also avoided.

It should be noted that the above three parts may be fixedly connected or movably connected, or detachably connected or non-detachably connected, or may be integrally formed. The spreading scraper 390 and the feeding pipe 351 are integrally formed, so that the effects of pouring and spreading materials can be realized; and the spreading blade 390, the material removing blade 370 and the feeding pipe 351 are integrally formed so that the material removing and spreading can be performed almost simultaneously.

Further, the spreading blade 390, the material removing blade 370, the feeding pipe 351 and the mixing device may be integrated into a whole, so that the structure of the 3D printing device is more compact.

Fig. 4 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention. Specifically, the printing apparatus in fig. 4 is a 3D printing apparatus of a sink type DLP, and the printing apparatus in fig. 1 is a 3D printing apparatus of an up type DLP. The printing apparatus in fig. 4 includes a bare engine 410, a tray 420, a forming platform 430, a lifting mechanism 440, a mixing device 450, a feeding pipe 451, a stirrer 452, a material box 460, a waste collecting device 480, a waste pipe 481, a waste bin 482 and a scraper 491, wherein the bare engine 410 is disposed above the tray 420, and the forming end surface is the upper end surface of the forming platform 430. A scraper 491 for scraping the liquid surface of the photosensitive resin is provided in the tray 420. The connection relationship, the mutual position relationship and the effect of the components not mentioned in the printing apparatus in fig. 4 are the same as those in the embodiment shown in fig. 1, and are not described again here.

Fig. 5 is a schematic structural diagram of a 3D printing apparatus according to another embodiment of the present invention. Specifically, the printing apparatus in fig. 5 is a 3D printing apparatus of SLA, and the printing apparatus in fig. 1 is a 3D printing apparatus of an ascending DLP. The printing apparatus of fig. 5 includes a laser 510, a tray 520, a forming platform 530, a lifting mechanism 540, a material mixing device 550, a feed tube 551, an agitator 552, a material box 560, a waste collection device 580, a waste conduit 581, a waste bin 582, and a scraper 591, wherein the light source device is the laser 510, the laser 510 is disposed above the tray 520, and the forming end surface is the upper end surface of the forming platform 530. A scraper 591 for scraping the liquid level of the photosensitive resin is provided in the tray 520. The connection relationship, the mutual position relationship and the effect of the components not mentioned in the printing apparatus in fig. 5 are the same as those in the embodiment shown in fig. 1, and are not described again here.

A comparison of the technical solutions of the embodiments shown in fig. 1, 4 and 5 is summarized as follows: the technical scheme shown in fig. 1 is an ascending DLP photocuring 3D printing device, and the bottom of a tray 120 is light-permeable; the light source device is an optical machine 110 and is arranged at the bottom of the material tray 120; the molding end face is the lower end face of the molding platform 130, and the molding surface is the bottom of the tray 120;

the technical scheme shown in fig. 4 is a sunken DLP photocuring 3D printing device, and the molding surface of the device is the liquid level of photosensitive resin. Although the scraper 491 scrapes the liquid surface of the photosensitive resin, the liquid surface of the photosensitive resin is still not as flat as the bottom of the tray 120 shown in fig. 1, that is, the molding surface of the rising DLP photocuring 3D printing device is more flat, and therefore the surface quality of the printed product is better.

The technical scheme shown in fig. 5 is an SLA photocuring 3D printing device. Likewise, the printing quality of the rising DLP photocuring 3D printing apparatus is also relatively better than that of the SLA photocuring 3D printing apparatus.

As some embodiments of the present disclosure, the light source device of the photocuring 3D printing device is an LCD light source.

Fig. 6 and 7 show a further modification of the mixing device according to the embodiment shown. As shown in fig. 6-7, the mixing device 650 is provided with a stirrer 652, a flow control module 654 and a heating device 655, wherein the flow control module 654 includes a control valve 6541 and a flow meter 6542 connected thereto. Flow control module 654 is positioned between material cartridge 660 and compounding device 650 to control and regulate the amount of resin material flowing from material cartridge 660 to compounding device 650. A feeding pipe 651 is communicated with the lower part of the mixing device 650.

The flow meter 6542 is used to measure the amount of the resin material supplied from a certain material cartridge 660 to the mixing device 650, and the control valve 6541 is used to control the communication and closing between the material cartridge 660 and the mixing device 650 based on the value measured by the flow meter 6542. The flow meter 6542 and the control valve 6541 are used in combination, and the mixing ratio of the respective resin materials can be controlled during mixing.

The heating means 655 can accelerate the evaporation of the washing liquid. In addition, the addition of the heating device 655 can improve the fluidity of the resin, so that the resin is mixed more uniformly, and a part of air bubbles generated in the process of stirring the resin can be discharged.

It is to be understood that the compounding device and its associated apparatus shown in fig. 6-7 can be combined with any of the foregoing embodiments of the invention without departing from the principles and spirit of the invention.

In the description herein, references to the description of "one embodiment," "another embodiment," or "certain embodiments," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A photocuring 3D printing device, characterized in that the 3D printing device includes:

the material tray is used for bearing photosensitive resin;

the lifting mechanism is used for driving the forming platform to move;

a plurality of material cartridges containing different photosensitive resins;

2. The photocuring 3D printing device of claim 1, wherein a flow control module is further disposed between the material box and the mixing device, and the flow control module comprises a control valve and a flow meter.

3. The photocuring 3D printing device according to claim 1, wherein a feeding pump is arranged in the feeding pipe, and the feeding pump is communicated with the material mixing device and the material tray through the feeding pipe respectively.

4. The photocuring 3D printing device according to claim 1, wherein the mixing device is further provided with a stirrer, and a stirring structure is arranged in the stirrer and extends into the mixing device.

5. The photocuring 3D printing device of claim 1, wherein a cleaner is further connected to the mixing device and used for removing residual materials in the mixing device.

6. The photocuring 3D printing device of claim 5, wherein the cleaner can deliver volatile cleaning liquid into the compounding device.

7. The photocuring 3D printing device of claim 1, wherein the compounding device is further provided with a heating device.

8. The photocuring 3D printing device of claim 1, further comprising a material removal scraper for scraping away uncured remnant material in the tray, the material removal scraper capable of planar motion.

9. The photocuring 3D printing device of claim 1, further comprising a lay-up blade capable of planar motion.

10. The photocuring 3D printing device of claim 1, wherein a residue collection tank is provided at the bottom of the tray, the residue collection tank being in communication with a waste conduit.

11. The photocuring 3D printing device of claim 9, wherein the feed tube is disposed forward of an advancement direction of planar motion of the spreading blade.

12. The photocuring 3D printing device of claim 11, further comprising a material removal scraper for scraping away uncured remnant material in the tray, the material removal scraper being capable of planar motion; compared to the spreading scraper, the material removal scraper is behind the spreading scraper in the forward direction of the planar movement.

13. The photocuring 3D printing device of claim 1, further comprising a material removal scraper for scraping away uncured remnant material in the tray, the material removal scraper being capable of planar motion;

the photocuring 3D printing device further comprises a spreading scraper, and the spreading scraper can do planar motion;

the spreading scraper, the feeding pipe and the material removing scraper are formed into an integral structure.

14. The photocuring 3D printing device of claim 9, wherein a liquid outlet is provided at an end of the spreading scraper close to the tray, and the liquid outlet is used for flowing out of the photosensitive resin liquid.