CN115648623A

CN115648623A - Feeding mechanism, 3D printer and 3D printing method

Info

Publication number: CN115648623A
Application number: CN202211286620.7A
Authority: CN
Inventors: 邓凌峰; 谢飞; 高炜旌; 万欣
Original assignee: Guangzhou Heygears IMC Inc
Current assignee: Guangzhou Heygears IMC Inc
Priority date: 2022-10-20
Filing date: 2022-10-20
Publication date: 2023-01-31
Also published as: WO2024083199A1

Abstract

The application provides a feeding mechanism, a 3D printer and a 3D printing method, and relates to the technical field of printing. The feeding mechanism comprises a material tray, a supporting structure and an air supply assembly. The charging tray includes the frame and sets up in the frame from the type membrane, and the relative both ends of frame have the opening, from one of them opening of type membrane shutoff frame, the frame with enclose jointly from the type membrane and become the chamber that holds that is used for holding printing material. The bearing structure sets up in deviating from one side that holds the chamber from the type membrane to and form the air feed chamber that has the air inlet from between the type membrane, support have with from the relative holding surface in type membrane interval, holding surface light-permeable. The gas supply assembly is in communication with the gas inlet and is configured to provide oxygen-enriched gas to the gas supply chamber. The feeding mechanism that this application embodiment provided can reduce the adhesion stress of printing layer and charging tray bottom with lower costs to improve the efficiency and the success rate that 3D printed.

Description

Feeding mechanism, 3D printer and 3D printing method

Technical Field

The application relates to the technical field of 3D printing, in particular to a feeding mechanism, a 3D printer and a 3D printing method.

Background

In the 3D printing process, the printing material in the material tray is solidified on the forming platform layer by layer. Specifically, in the printing process of one layer, the forming platform is pressed to the bottom of the material tray, and the printing material between the bottom of the material tray and the forming platform is solidified and bonded on the forming platform. It will be appreciated that the solidified marking material also has some adhesion to the bottom of the tray and therefore needs to be peeled off the bottom of the tray in order to print the next layer. The greater the adhesion between the bottom of the tray and the print, the greater the peel force required. The influence of the stripping force on the printing efficiency is large, the higher the stripping force is, the lower the printing efficiency is, and the overlarge stripping force can cause a printed piece to fall off from a forming platform, so that the printing failure is caused. In the existing 3D printing process, the problem of large adhesive force between a printed part and the bottom of a material tray still exists.

Disclosure of Invention

The purpose of this application is including providing a feeding mechanism, 3D printer and 3D printing method, and it can make the easy and charging tray bottom adhesive force between reduce of printing to reduce peel strength, and then improve and print efficiency and success rate.

The embodiment of the application can be realized as follows:

in a first aspect, the present application provides a feeding mechanism for a 3D printer, including:

the material tray comprises a frame and a release film, wherein openings are formed in two opposite ends of the frame, the release film is plugged at one opening of the frame, and the frame and the release film jointly enclose a containing cavity for containing printing materials;

the supporting structure is arranged on one side of the release film, which is far away from the accommodating cavity, and an air supply cavity with an air inlet is formed between the supporting structure and the release film; and

and the gas supply assembly is communicated with the gas inlet and is used for supplying oxygen-enriched gas to the gas supply cavity.

In an alternative embodiment, the gas supply assembly includes a gas source for storing or preparing the oxygen-enriched gas, the gas source being in communication with the gas inlet.

In an alternative embodiment, the oxygen-enriched gas in the gas supply chamber is consumed only through the release film.

In an alternative embodiment, the rate of consumption of the oxygen-enriched gas in the gas supply chamber is less than a predetermined rate.

In an alternative embodiment, the gas source is at least one of a disposable oxygen inhalation cylinder, a pop can type oxygen cylinder, a snuff type oxygen cylinder, and a mask type oxygen cylinder.

In an alternative embodiment, the gas source is at least one of an oxygen generator, an oxygen generator.

In an optional embodiment, the gas supply assembly further comprises a pipeline and a speed regulating valve arranged on the pipeline, the gas source is communicated with the gas inlet through the pipeline, and the speed regulating valve is used for regulating the flow of the oxygen-enriched gas entering the gas supply cavity.

In an alternative embodiment, the gas supply assembly further comprises a first gas pressure gauge for sensing the gas pressure within the gas supply chamber.

In an optional embodiment, the gas supply assembly further comprises a controller and an electromagnetic valve arranged in the pipeline, the electromagnetic valve and the first pressure gauge are both electrically connected with the controller, and the controller is configured to control the on-off of the electromagnetic valve according to pressure information fed back by the first pressure gauge.

In an alternative embodiment, the gas supply assembly further comprises a second gas pressure gauge for detecting the gas pressure within the gas source.

In an alternative embodiment, the gas supply assembly further comprises a pressure maintaining valve disposed in the conduit for outputting the oxygen-enriched gas at a stable gas pressure.

In an alternative embodiment, the air supply assembly further comprises a drying duct disposed in the duct.

In an alternative embodiment, the release film is any one of a fluoropolymer film, a Polydimethylsiloxane (PDMS) film, and a polymethylpentene (PMP) film.

In an alternative embodiment, the fluoropolymer membrane is at least one of FEP membrane, nFEP membrane, PTFE membrane, ETFE membrane, PFA membrane, PVDF membrane, PVF membrane.

In an optional embodiment, the support structure comprises a support member, the support member is connected to the tray in a sealing manner, the support surface is formed on the support member, and the air supply cavity is formed between the support surface and the release film.

In an alternative embodiment, the support is a light-transmissive glass.

In an alternative embodiment, the support is an LCD screen, and the LCD screen is either an LCD or an LCOS.

In an alternative embodiment, the support structure further comprises a transparent cover plate, and the transparent cover plate is arranged on the side of the support member, which faces away from the release film, in a stacked manner.

In an alternative embodiment, the support member is an LED screen, and the LED screen is any one of an OLED, a Micro-LED, a Mini-LED, a Micro-OLED and a Mini-OLED.

In an optional embodiment, the supporting structure comprises a supporting piece and a sealing plate, the sealing plate and the supporting piece are arranged at intervals, the sealing plate is connected with the material tray in a sealing mode, the air supply cavity is formed between the sealing plate and the release film, the supporting piece is located in the air supply cavity, and the supporting surface is formed on the supporting piece.

In an alternative embodiment, the release film has an oxygen permeability of 0.1barrer or greater. The oxygen permeability of the release film can be more than 1barrer, 5barrer, 10barrer, 30barrer, 100barrer or 1000 barrer.

In an alternative embodiment, the release film has an oxygen permeability of 20barrer or less. The oxygen permeability of the release film can be 15barrer, 10barrer, 5barrer or below 1 barrer.

In an alternative embodiment, at least a partial region of one surface of the release film facing the accommodating cavity is a rough region.

In an alternative embodiment, the distance between the release film and the support surface is not more than 5mm. The distance between the release film and the support surface can be not more than 3mm, 2mm, 1mm, 0.5mm or 0.2mm.

In an alternative embodiment, the gas supply assembly further comprises an oxygen concentration sensor for detecting the concentration of oxygen in the gas source or supply chamber.

In an alternative embodiment, the gas supply chamber also has a gas outlet; the air outlet is communicated with the atmosphere, or the air outlet is communicated with an air source through a pipeline to form a circulating air path.

In a second aspect, the present application provides a 3D printer, including a forming platform and the feeding mechanism of any one of the foregoing embodiments, wherein the forming platform is used for attaching a print, and the forming platform is movable relative to the feeding mechanism to extend into or move out of the accommodating cavity of the tray.

In a third aspect, the present application provides a 3D printing method, which is applied to the 3D printer of the foregoing embodiment, where the 3D printing method includes:

controlling the gas supply assembly to supply oxygen-enriched gas to the gas supply cavity;

exposing the printing material in the tray to form a printing layer adhered on the forming platform;

and controlling the forming platform to be far away from the feeding mechanism so as to separate the printing layer from the release film.

In an alternative embodiment, the release film is maintained in contact with the support surface during exposure of the printing material in the tray.

In an alternative embodiment, during the exposure of the printing material in the tray, the air pressure in the air supply chamber is not higher than the atmospheric pressure by 1kpa. The air pressure in the air supply chamber may be no more than 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2 or 0.1kpa above atmospheric pressure.

In an alternative embodiment, in the process of controlling the forming platform to be away from the feeding mechanism so as to separate the printing layer from the release film, the gas supply assembly is controlled to supply gas to the gas supply cavity so as to make the release film protrude in a direction away from the support structure.

In an optional embodiment, before controlling the forming platform to be away from the feeding mechanism to separate the printing layer from the release film, the 3D printing method further includes:

detecting the air pressure in the air supply cavity;

under the condition that the air pressure in the air supply cavity is smaller than a first preset air pressure, controlling the air supply assembly to deliver oxygen-enriched air to the air supply cavity;

under the condition that the air pressure in the air supply cavity is greater than a second preset air pressure, controlling the air supply assembly to stop supplying the oxygen-enriched air to the air supply cavity;

wherein the second preset air pressure is greater than the first preset air pressure.

In an alternative embodiment, the 3D printing method further comprises controlling the oxygen-enriched gas in the gas supply chamber to be consumed only through the release film.

In an alternative embodiment, the 3D printing method further comprises controlling the consumption rate of the oxygen-enriched gas in the gas supply chamber to be less than a preset rate.

In an optional embodiment, the gas source is at least one of a disposable oxygen inhalation bottle, a pop can type oxygen bottle, a nasal inhalation type oxygen bottle and a mask type oxygen bottle.

The beneficial effects of the embodiment of the application include, for example:

the feeding mechanism that this application embodiment provided includes charging tray, bearing structure and air feed subassembly. Wherein, the charging tray includes the frame and sets up in the type membrane of leaving of frame, and the relative both ends of frame have the opening, from one of them opening of type membrane shutoff frame, and the frame encloses the chamber that holds that is used for holding printing material jointly with leaving the type membrane. The supporting structure is arranged on one side of the release film deviating from the accommodating cavity, and forms an air supply cavity with an air inlet between the release films, and the supporting structure is provided with a supporting surface opposite to the release film at an interval and is light-permeable. The gas supply assembly is in communication with the gas inlet and is configured to provide oxygen-enriched gas to the gas supply chamber. The 3D printing piece that this application embodiment provided includes shaping platform and foretell feed mechanism. The 3D printing method provided by the embodiment of the application is applied to the 3D printer and comprises the steps of controlling the gas supply assembly to supply oxygen-enriched gas to the gas supply cavity; and forming the printing piece layer by layer on the forming platform by exposing the printing material in the tray. In the feeding mechanism of this application embodiment, bearing structure and from having formed the air feed chamber between the type membrane, the air feed chamber can hold the oxygen-enriched gas who is provided by the air feed subassembly, and oxygen among the oxygen-enriched gas can enter into the chamber that holds of charging tray through from the type membrane to a certain extent. Based on the oxygen inhibition effect of the photo-curable printing material, the adhesive force between the inner surface of the release film and the photo-curable printing layer is reduced to facilitate peeling. And, in this embodiment, when the pressure effect of the gravity of printing material or shaping platform from the type membrane, when protruding to the bearing structure direction, bearing structure's holding surface can play certain supporting role to from the type membrane, consequently at the printing in-process, can not excessively warp the extension as the holding surface that can paste from the type membrane of charging tray bottom, guarantees from the roughness of type membrane shaping face to improve print quality. Therefore, the feeding mechanism provided by the embodiment of the application can lower the bonding force between the printing layer and the bottom of the material tray, so that the 3D printing efficiency and the success rate are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a schematic view of a tray and a support structure engaged from a first perspective in an embodiment of the present application;

FIG. 2 is a schematic view of the tray and support structure from a second perspective in an embodiment of the present application;

FIG. 3 isbase:Sub>A cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a schematic view of the tray and support structure in another embodiment of the present application;

FIG. 5 is a cross-sectional view taken along line B-B of FIG. 4;

FIG. 6 is a schematic view of the tray and the support structure in yet another embodiment of the present application;

FIG. 7 is a cross-sectional view taken along line C-C of FIG. 6;

FIG. 8 is a schematic view of the connection of the gas supply assembly to the tray in one embodiment of the present application;

FIG. 9 is a schematic structural diagram of a 3D printer according to an embodiment of the present application;

fig. 10 is a flowchart of a 3D printing method according to an embodiment of the present application.

Icon: 10-3D printer; 100-material tray; 101-a containment chamber; 110-a frame; 120-a release film; 200-a support structure; 201-air supply cavity; 202-an air inlet; 203-air outlet; 210-a support; 220-sealing plate; 230-a transparent cover plate; 240-a support frame; 250-a fresnel lens; 300-a substrate; 40-a gas supply assembly; 400-air source; 410-a pipeline; 420-speed regulating valve; 430-solenoid valve; 440-a first barometer; 450-a second barometer; 460-a pressure maintaining valve; 470-drying tube; 480-a controller; 500-a forming table; 600-a lifting mechanism; 700-a connecting frame; 800-light source.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, as presented in the figures, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present application, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. are used for indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship which the present invention product is usually put into use, it is only for convenience of describing the present application and simplifying the description, but it is not intended to indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation and be operated, and thus, should not be construed as limiting the present application.

It should be noted that the features of the embodiments of the present application may be combined with each other without conflict.

Photocuring printer is at 3D printing process, and the printing material successive layer solidification in the charging tray is on the shaping platform. The first printing layer is formed between the bottom of the material tray and the forming platform; and subsequent print layers are formed between the bottom of the tray and the cured print layer. After each layer is printed, the forming table needs to be raised a distance in order to print the next layer. It can be understood that the solidified printing layer has a certain adhesion with the bottom of the tray, so that the printing layer can be peeled off from the bottom of the tray when the forming platform is lifted. In the related art, the adhesion between the bottom of the tray and the printed matter is large, and the required stripping force is large. The lower the printing efficiency, due to the greater peel force required. Moreover, if the required peel force is greater than the adhesion between the print and the forming table, it can cause the print to fall off the forming table, which in turn can lead to printing failures.

In order to improve the too big problem of printing in the correlation technique and charging tray bottom adhesion stress, this application embodiment provides a feeding mechanism, form the air feed chamber through leaving type membrane below at the charging tray bottom, to leaving type membrane upper surface one side oxygen suppliment through the air feed chamber to reduce from the adhesion stress between type membrane and the printing, and then improve printing efficiency and printing success rate. The embodiment of the application also provides a 3D printer and a 3D printing method, the bottom of the charging tray is supplied with oxygen from the air supply cavity below the release film through the feeding mechanism in the printing process, so that oxygen can diffuse to the upper surface through the lower surface of the release film, oxygen polymerization inhibition reaction is formed with the light-cured resin in the charging tray, the bonding force between the printing piece and the charging tray from the release film is further reduced, the peeling force between the printing piece and the release film after curing and forming is reduced, the printing speed is increased, and the printing efficiency and the printing success rate are improved.

Fig. 1 is a schematic view of a tray 100 and a support structure 200 engaged from a first perspective in an embodiment of the present invention; fig. 2 is a schematic view of the tray 100 and the support structure 200 from a second perspective in an embodiment of the present invention; fig. 3 isbase:Sub>A sectional view taken along the directionbase:Sub>A-base:Sub>A in fig. 2, and fig. 9 isbase:Sub>A schematic structural view ofbase:Sub>A 3D printer according to an embodiment. Referring to fig. 1 to 3 and fig. 9, a feeding mechanism provided in the present embodiment is suitable for a photo-curing printer, and the feeding mechanism includes a tray 100, a supporting structure 200 and a gas supply assembly 40. The tray 100 is for containing printing material; the supporting structure 200 is positioned below the charging tray 100 so as to jointly enclose an air supply cavity 201 with the bottom of the charging tray 100; the gas supply assembly is used to provide oxygen-enriched gas to the gas supply chamber 201.

In the embodiment of the present application, the tray 100 includes a frame 110 and a release film 120 disposed on the frame 110, and the frame 110 has openings at two opposite ends, i.e., an upper opening and a lower opening. The release film 120 is sealed at the lower opening of the frame 110, thereby forming the bottom of the tray 100. The frame 110 and the release film 120 jointly enclose a containing cavity 101 for containing a printing material, and an upper opening of the frame 110 is used as an opening of the containing cavity 101 for a forming platform of the 3D printer to extend into. In this application embodiment, from type membrane 120 light-permeable, light can be from down passing from type membrane 120 to the ground, shines the printing material who holds in the chamber 101 to solidification printing material forms the printing.

As shown in the figure, the frame 110 of the tray 100 is a rectangular frame, and thus encloses a rectangular accommodating cavity 101 together with the release film 120. In alternative embodiments, the shape of the frame 110 of the tray 100 can be selected according to specific needs, including but not limited to circular, oval.

In the present embodiment, the release film 120 has a certain oxygen permeability, so that oxygen in the gas supply chamber 201 outside the release film 120 (the side away from the accommodating chamber 101) can enter the inside of the release film 120 (the side facing the accommodating chamber 101) to some extent through the release film 120. According to the property of the release film 120 that oxygen is permeable, oxygen in the gas supply chamber 201 can pass through the release film 120 and gather near the inner side of the release film 120 during printing, so as to reduce the adhesive force between the printed layer and the release film 120, thereby reducing the peeling force of the printed layer. Alternatively, the release film 120 includes, but is not limited to, a fluoropolymer film, a Polydimethylsiloxane (PDMS) film, and a polymethylpentene (PMP) film. Optionally, the oxygen permeability of the release film 120 is above 0.1 barrer. The oxygen permeability of the release film can also be more than 1barrer, 5barrer, 10barrer, 30barrer, 100barrer or 1000 barrer. For example, the release film 120 may be a teflon oxygen permeable film with high oxygen permeability, such as AF2400, AF1600, or the like, and may be at least one of polydimethylsiloxane, poly (4-methyl-2-pentyne), and polymethylpentene.

Optionally, in order to reduce the cost and reduce the oxygen consumption, the release film 120 with a low oxygen permeability may be selected, for example, the oxygen permeability of the release film is less than 20 barrer. For another example, the oxygen permeability of the release film 120 is 15barrer, 10barrer, 5barrer, or 1barrer or less. Alternatively, the release film 120 includes, but is not limited to, FEP film, nFEP film, PTFE film, PFA film, PVDF film, PVF film. The general release film 120 also has at least slight oxygen permeability, so that oxygen in the gas supply chamber 201 can enter the receiving chamber 101 to some extent through the release film 120. Generally speaking, as long as it has oxygen permeability from type membrane 120, can let oxygen pass through and get into the charging tray, can realize the effect that the reduction of this application was printed piece and charging tray were from type membrane adhesion to reduce peel force, promote and print the success rate.

In this embodiment, the oxygen in the gas supply chamber 201 permeates from the outside to the inside of the release film 120, so the printing material near the inside of the release film 120 contains more oxygen. Based on the oxygen inhibition effect of the photo-curable printing material, a thin layer of printing material (with a thickness of micron order) that is relatively difficult to cure or in a semi-cured state is formed near the inner surface of the release film 120, so that the printing material is not easily adhered to the release film 120 too firmly due to curing, and the release film 120 is conveniently separated from a printed product in the process of lifting the forming platform 500.

In an alternative embodiment, at least a partial region of a surface of the release film 120 facing the accommodating chamber 101 is a rough region. Alternatively, the entire surface or a partial area of the release film 120 facing the receiving chamber 101 may be roughened to improve roughness. Through setting up the coarse region, can increase the area of releasing oxygen from the inboard of type membrane 120 to increase the oxygen permeability from the type membrane 120 medial surface, and then reduce the printing and from the adhesive force between the type membrane 120 more effectively, reduce and peel off the degree of difficulty. While the roughened region and the printing material conform to provide minimal scattering effects. Also, by providing the roughened region, the jaggies of the pixels can be blurred, for example, in a topological structure, a patterned structure. In the present embodiment, the roughness is lower than the pixel scale, so that the surface quality of the printed matter can be improved without affecting the accuracy.

The supporting structure 200 is disposed on a side of the release film 120 away from the accommodating chamber 101, and a gas supply chamber 201 having a gas inlet 202 is formed between the supporting structure and the release film 120. In the present embodiment, the supporting structure 200 includes a supporting member 210, and the supporting member 210 has a supporting surface spaced from and opposite to the release film 120, and the supporting surface is light-permeable. It should be understood that the release film 120 is flexible, so that the support 210 can provide effective support for the release film 120 when the release film 120 collapses to the direction of the support 210 due to the gravity of the printing material, the pressure of the forming platform and/or the negative pressure of the air supply chamber 201. When the release film 120 is supported by the support 210, the inner surface of the release film 120 is kept flat because the release film 120 is attached to the support 210, which is beneficial to the flatness of the cured and molded printed layer and the printing precision.

In a case where the release film 120 is not collapsed downward, an air gap may be formed between the support 210 and the release film 120, and the oxygen-rich gas may remain in the air gap and enter the receiving cavity 101 through the release film 120. If the thickness of the air gap is too large, the position of the inner surface of the release film 120 (i.e., the molding surface of the release film 120) is moved too much during the printing process, which results in an unsatisfactory precision. Because if the air gap is thicker, the molding surface of the release film 120 may be displaced downward by a larger amount, resulting in a reduction in printing accuracy. In an alternative embodiment, in the case where the release film 120 is flat (not collapsed and not raised), the distance between the release film 120 and the support surface is not greater than 5mm, and the distance between the release film and the support surface may be not greater than 3mm, 2mm, 1mm, 0.5mm, or 0.2mm. For example, 0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5, etc., or not greater than 1mm, for example, 0.2mm, 0.4mm, 0.6mm, 0.8mm, etc., or not greater than 0.5mm, for example, 0.1mm, 0.3mm, 0.5mm, etc., is used. Too big from the distance between type membrane 120 and the holding surface, can lead to holding the chamber too big, and then make to push down at the shaping platform, the in-process of contact from type membrane 120 solidification is from the type membrane to holding the chamber extension or take place elastic deformation, and the individual layer thickness that leads to the actual solidification is greater than predetermined individual layer thick, and then influences the printing quality. From the distance undersize between type membrane 120 and the holding surface, then can make the space that holds the chamber less, logical oxygen or oxygen storage volume can not reach the requirement, and then can not realize the technological effect of this application well.

In the embodiment of fig. 3, the support member 210 is hermetically connected to the tray 100, and the air supply chamber 201 is formed between the support surface and the release film 120. It should be understood that the support member 210 is hermetically connected to the tray 100, meaning that the connection position is not permeable to air, and the air supply chamber 201 can only exchange air through the specially provided openings (such as the air inlet 202 and the air outlet 203) or the release film 120. In this embodiment, the supporting member 210 is a transparent glass. The glass has better light transmission and wear resistance and lower cost. In alternative embodiments, the supporting member 210 may also be selected to be a light-transmissive organic material. The light source of 3D printer can set up in support piece 210 below, and the light that is used for the solidification can loop through support piece 210, air feed chamber 201, enter into from type membrane 120 and hold the intracavity 101 and shine the printing material to the order printing material solidification.

The gas supply chamber 201 is provided with a gas inlet 202 and a gas outlet 203, wherein the gas inlet 202 is used for allowing oxygen-enriched gas to enter, and the gas outlet 203 is used for discharging gas in the gas supply chamber 201. For example, when the oxygen-rich gas with the required oxygen content is supplied from the gas inlet 202, the oxygen content of the oxygen-rich gas is decreased after the oxygen is supplied to the inner side of the release film 120 in the gas supply chamber 201, and the gas with the oxygen content decreased to a level not meeting the oxygen supply requirement is discharged from the gas outlet 203. In this way, the gas in the gas supply chamber 201 can be easily made to have a stable oxygen content, so that the oxygen content near the inner side of the release film 120 can be stabilized within a target range, thereby continuously and stably exerting the oxygen inhibition effect and reducing the peeling force between the print and the release film 120. In the present embodiment, the air inlet 202 and the air outlet 203 are respectively disposed at two opposite corners of the support structure 200. In an alternative embodiment, only the gas inlet 202 may be provided without the gas outlet 203, in other words, the gas outlet 203 in this embodiment may also be connected to the gas supply assembly as the gas inlet 202, that is, the oxygen-enriched gas may be supplied to the gas supply chamber 201 through two gas inlets 202.

In this embodiment, the supporting member 210 is used to form the air supply chamber 201 and also to support the release film 120. In alternative other embodiments, the support member 210 may serve only a supporting function without participating in constituting the air supply chamber 201. Fig. 4 is a schematic view of the tray 100 and the support structure 200 in another embodiment of the present application; fig. 5 is a sectional view taken along the line B-B in fig. 4. As shown in fig. 4 and 5, the supporting structure 200 in this embodiment further includes a sealing plate 220 and a supporting frame 240. The sealing plate 220 and the supporting member 210 are arranged in parallel at intervals, the sealing plate 220 is connected with the tray 100 in a sealing manner through the supporting frame 240, and the air supply cavity 201 is formed between the sealing plate 220 and the release film 120. The support member 210 is located in the air supply chamber 201 and fixed by the support frame 240. And, an air gap is formed between the release film 120 and the release film 120 without the release film 120 collapsing. In the present embodiment, the sealing plate 220 participates in forming the air supply chamber 201, and the supporting member 210 only plays a role of supporting and transmitting light. Through setting up closing plate 220 for the whole space of air feed chamber 201 obtains increasing, can hold more oxygen-enriched gas, has also improved the homogeneity of gas diffusion. The sealing plate 220 and the supporting member 210 are both transparent to light. The material of the support member 210 and the sealing plate 220 may be glass or resin.

Fig. 6 is a schematic view of the tray 100 and the supporting structure 200 according to still another embodiment of the present application; fig. 7 is a sectional view taken in the direction C-C in fig. 6. The structure in the embodiment of fig. 6 and 7 is suitable for an LCD photo-curing printer. In the present embodiment, the supporting member 210 is an LCD screen, and the LCD screen is any one of LCD and LCOS, and the LCD screen is selectively transparent. It should be understood that the 3D printer to which the feeding mechanism of the present embodiment is applied should further include a backlight source, wherein the backlight source projects light to the supporting member 210, and the supporting member 210 selectively transmits the light to inject light required for printing into the accommodating chamber 101. In this embodiment, the supporting member 210 is connected to the tray 100 in a sealing manner, so that the air supply cavity 201 is formed between the supporting surface of the supporting member 210 and the release film 120. Also shown is a base plate 300 of the 3D printer, the base plate 300 having a window, and the feeding mechanism being disposed at the window of the base plate 300, the support structure 200 being fixedly connected to the base plate 300.

In this embodiment, the supporting structure 200 further includes a transparent cover 230, and the transparent cover 230 is disposed on a side of the supporting member 210 facing away from the release film 120 in a stacked manner. Further, the feeding mechanism of the present embodiment further includes a fresnel lens 250, and the fresnel lens 250 is disposed on the transparent cover plate 230 and a side away from the release film 120. The fresnel lens 250, the transparent cover plate 230 and the support 210 are spaced in parallel.

It can be seen that in the present embodiment, the supporting member 210 not only functions to support, transmit light, and form the air supply chamber 201, but also functions to selectively transmit light to adjust the printing light. In the embodiment where the supporting member 210 is a transparent plate, the external light source is required to have the function of intelligent dimming, so that the printed product with the target shape can be printed.

Further, in other optional embodiments, the support 210 may also be an LED screen, and a light emitting surface of the LED screen is a support surface and faces the release film 120. In this embodiment, the supporting member 210 not only functions to support the release film 120 and form the air supply chamber 201, but also functions as a light source by self-luminescence. It should be understood that in the present embodiment, the supporting surface of the LED screen is also transparent, and the LED emits light to the release film 120 through the supporting surface. Specifically, the LED screen may include one of an OLED (Organic Light-Emitting Diode), a Micro-LED, a Mini-LED, a Micro-OLED, and a Mini-OLED.

In this embodiment, the gas supply assembly 40 is in communication with the gas inlet 202 and is used to provide oxygen-enriched gas to the gas supply chamber 201. The gas supply assembly 40 includes a gas source 400 (see fig. 8), the gas source 400 being used to store or prepare the oxygen-enriched gas, the gas source 400 being in communication with the gas inlet 202. Through supplying oxygen-enriched gas into the air feed intracavity, can guarantee to be in the oxygen-enriched environment from the type membrane 120 outside, and then can guarantee to form oxygen inhibition effect from type membrane 120 inboard to reduce the printing and from the cohesive force between the type membrane 120. When the air supply is the container that is used for saving oxygen-enriched gas, the portable oxygen cylinder that the volume is less can be selected to air supply 400, is favorable to integrating the air supply inside the 3D printer like this, also reduces cost simultaneously, and convenient family expenses are suitable for in the consumer grade printer. For example, the gas source 400 may be one of a disposable oxygen cylinder, a pop-top can, a nasal inhalation type oxygen cylinder, or a mask type oxygen cylinder. Through selecting portable disposable air supply for use, cooperate the release film of low oxygen permeability, can reduce the consumption of air supply, promote the live time of air supply to probably accomplish the printing of great work piece under few oxygen consumption, improve printing efficiency. Air supply 400 can select miniature oxygen generator, oxygenerator, for example can be domestic oxygenerator, realizes making oxygen through compressed air, and the oxygen concentration of the oxygen of making is the highest 95% or even about 90%, compares in industrial level system oxygen mode, and it is more convenient, popularize easily, can also realize medical oxygenerator, generally for the pressure swing adsorption oxygenerator, adopts the pressure swing adsorption technique system oxygen, can follow and draw out oxygen in the air. The air source can also be an integrated oxygen generator, and core components (such as a compression pump, a molecular sieve and the like) of the oxygen generator are integrated on the 3D printer.

In an alternative embodiment, the oxygen-enriched gas in the gas supply chamber 201 is consumed only by the release film 120, in other words, the gas supply chamber 201 is communicated with the gas source only by the gas inlet 202, and the oxygen-enriched gas in the gas supply chamber 201 is consumed only by means of slow diffusion to the outside through the release film 120. Since the release film 120 permeates oxygen slowly, the consumption of the oxygen-enriched gas in the gas source is slow, so that the waste of oxygen can be reduced as much as possible, and the pressure of the gas supply chamber 201 can be controlled more easily.

Fig. 8 is a schematic view of the connection of the gas supply assembly to the tray 100 in one embodiment of the present application. As shown in fig. 8, in the present embodiment, the air supply assembly 40 further includes a pipeline 410, and a speed regulating valve 420, a solenoid valve 430, a pressure maintaining valve 460, and a drying tube 470 which are disposed in the pipeline 410, and further, the air supply assembly 40 further includes a controller 480, a first air pressure gauge 440, and a second air pressure gauge 450. The gas source 400 is communicated with the gas inlet 202 through a pipeline 410, and the speed regulating valve 420 is used for regulating the flow of the oxygen-enriched gas entering the gas supply chamber 201, so that the gas pressure in the gas supply chamber 201 can also be controlled to a certain degree. The first air pressure gauge 440 is used to detect the air pressure in the air supply chamber 201, and may be specifically disposed on the pipe 410 on the side close to the air inlet 202. The second pressure gauge 450 is used for detecting the pressure of the gas in the gas source 400, and may be specifically disposed on the pipeline 410 close to the gas source 400, and the pressure information detected by the second pressure gauge 450 can be used for obtaining the remaining amount of the oxygen-enriched gas in the gas source 400. Pressure maintaining valve 460 is used to output oxygen enriched gas at a steady pressure. The drying tube 470 is used to remove moisture from the oxygen-enriched gas.

Further, the electromagnetic valve 430 and the first pressure gauge 440 are both electrically connected to the controller 480, and the controller 480 is configured to control on/off of the electromagnetic valve 430 according to the pressure information fed back by the first pressure gauge 440. Therefore, the air pressure in the air supply cavity 201 can be automatically adjusted, so that the air supply cavity is kept within a certain range, and the printing requirement is met.

It can be seen that the controller 480, the speed regulating valve 420, the first pressure gauge 440, the solenoid valve 430, the pressure stabilizing valve 460, etc. together form a pressure stabilizing system to precisely control the air pressure in the air supply chamber 201.

In a specific embodiment, the consumption rate of the oxygen-enriched gas in the gas supply chamber 201 can be adjusted to be less than the predetermined rate by adjusting the pressure in the gas supply chamber 201, selecting a suitable release film 120, and the like. The consumption rate of the oxygen-enriched gas is controlled to be smaller than the preset rate, so that the oxygen-enriched gas can be used for ensuring that the gas source can meet the printing of a certain number of times or a certain duration, for example, the printing of a single time, the printing of ten times, the printing of five hours and the like can be met, and the preset rate can be determined according to specific requirements. Moreover, the consumption rate of the oxygen-enriched gas is controlled at a lower level, so that the scheme of using a portable gas source with smaller gas storage capacity is more facilitated, even if the portable gas source with smaller volume is used, the printing requirement can still be met for a certain number of times or a certain length of time, and the requirement for equipment miniaturization is met.

Further, the gas supply assembly 40 further includes an oxygen concentration sensor for detecting the concentration of oxygen in the gas source or the gas supply chamber 201. When the oxygen concentration is lower than the target value, fresh oxygen-enriched gas can be supplied to the gas supply chamber 201 in time.

In other embodiments, the gas supply chamber 201 has a gas inlet 202 and a gas outlet 203, and the oxygen-enriched gas enters from the gas inlet 202, is absorbed by the release film 120, and then is directly discharged to the atmosphere from the gas outlet 203. This way it is possible to keep the oxygen content in the gas supply chamber 201 always close to the oxygen content in the gas source, but the consumption of oxygen-enriched gas is large. In an alternative embodiment, the gas outlet 203 can be connected to the gas source through a pipeline to form a circulating gas path, which can also save the oxygen-enriched gas in the gas source, thereby reducing the cost. Under the condition of less consumption of the oxygen-enriched gas, the portable gas source with smaller volume is more favorable for providing the oxygen-enriched gas. In the scheme with both the gas inlet 202 and the gas outlet 203, for oxygen concentration monitoring, an oxygen concentration sensor can also be installed at the gas outlet 203, so that the oxygen content of the exhaust gas can be known; alternatively, oxygen concentration sensors may be installed in both the gas inlet 202 and the gas outlet 203.

In a specific embodiment, an air pump may be further provided in the piping of the air supply assembly 40, by which the air pressure in the air supply chamber 201 can be effectively adjusted.

In an alternative embodiment, the oxygen-enriched gas stored (or produced) in the gas source may be selected to be greater than 21% and less than 99% in a concentration sufficient to achieve an oxygen inhibition effect inside the release film 120, thereby reducing the print's peel force. Since the printing material (usually resin) contains dissolved oxygen, nitrogen, etc., wherein the content of oxygen is originally balanced with the air, if a pure oxygen atmosphere is used, the nitrogen in the resin will penetrate through the release film 120 and enter into the film, especially for the unexposed area, the content of oxygen in the resin in the area will be increased and exceed the amount balanced with the content of oxygen in the air, and the time required for the subsequent exposure of the area will be increased, and the normal exposure time is fixed, so the underexposure may occur.

An embodiment of the present application further provides a 3D printer 10, as shown in fig. 9, which is a schematic structural diagram of the 3D printer in an embodiment of the present application, and includes a feeding mechanism provided in the foregoing embodiment, and specific structures and related functions of the feeding mechanism may refer to the foregoing embodiment, and are not described herein again. In addition, the 3D printer further includes a forming platform 500, the forming platform 500 is used for attaching the printed material, and the forming platform 500 is movable relative to the feeding mechanism to extend into the accommodating cavity 101 of the tray 100 or move out of the accommodating cavity 101 of the tray 100. During printing, the first printing layer is formed between the forming platform 500 and the release film 120 and attached to the forming platform 500, and the subsequent printing layer is attached to the cured printing layer. It should be understood that the 3D printer should also include other components necessary for implementing photocuring 3D printing, such as a control module, a light source 800 (in the case where the feeding mechanism does not include a light source), a lifting mechanism 600, and a connecting frame 700 for connecting the forming platform and the lifting mechanism.

Fig. 10 is a flowchart of a 3D printing method according to an embodiment of the present application. As shown in fig. 10, an embodiment of the present application further provides a 3D printing method, and a specific structure and related functions of the 3D printer according to the above embodiment are as described in the above embodiment, and are not described herein again. The 3D printing method comprises the following steps:

s100, controlling a gas supply assembly to supply oxygen-enriched gas to a gas supply cavity;

step S200, exposing the printing material in the tray to form a printing layer adhered to the forming platform;

and step S300, controlling the forming platform to be far away from the feeding mechanism so as to separate the printing layer from the release film.

Optionally, in the process of exposing the printing material in the tray 100, the release film 120 is kept in contact with the supporting surface of the supporting member 210, so that the release film 120 is kept flat, and the printing effect is ensured. Optionally, the air pressure in the air supply cavity 201 is not higher than 1kpa above atmospheric pressure, such as not higher than 0.1kpa, 0.2kpa, 0.3kpa, 0.4kpa, 0.5kpa, 0.6kpa, 0.7kpa, 0.8kpa, 0.9kpa above ambient atmospheric pressure, or a value between any two points.

After each printed layer is printed, the forming platform 500 is controlled by the control mechanism to be away from the feeding mechanism through the elevator and the connecting frame, so as to separate the printed layer from the release film 120. Wherein, in the process of controlling the forming platform 500 to be away from the feeding mechanism so as to separate the printing layer from the release film 120, the gas supply assembly 40 is controlled to supply gas to the gas supply cavity 201 so as to make the release film 120 protrude in the direction away from the supporting structure 200, thereby facilitating the separation of the printing layer from the release film 120.

Optionally, the forming platform 500 is controlled to be away from the feeding mechanism, so that before the printing layer is separated from the release film, the 3D printing method further includes:

detecting the air pressure in the air supply cavity 201; under the condition that the air pressure in the air supply cavity 201 is smaller than a first preset air pressure, controlling the air supply assembly to deliver oxygen-enriched air to the air supply cavity 201; controlling the gas supply assembly to stop supplying the oxygen-enriched gas to the gas supply cavity 201 under the condition that the gas pressure in the gas supply cavity 201 is greater than a second preset gas pressure; wherein the second preset air pressure is greater than the first preset air pressure.

In this embodiment, since the air pressure in the air supply chamber 201 can reflect the content of the oxygen-enriched air in the air supply chamber 201, when the air pressure in the air supply chamber 201 is smaller than the first preset air pressure, it means that the content of the oxygen-enriched air in the air supply chamber 201 is less, and it is difficult to meet the requirement of reducing the peeling force, so that the air supply assembly needs to be controlled to deliver the oxygen-enriched air to the air supply chamber 201 for supplement. If the air pressure in the air supply cavity 201 is greater than the second preset air pressure, it means that the oxygen-enriched air in the air supply cavity 201 is sufficient, and too high air pressure may cause the release film 120 to protrude upwards, the forming surface to be uneven, and the printing effect to be poor. The gas supply assembly is thus controlled to stop delivering oxygen-enriched gas to the gas supply chamber 201. By the above control, the air pressure in the air supply chamber 201 can be stabilized within a reasonable range before the printed layer is peeled off (including the exposure process and the waiting process before the exposure). Further, when the air pressure in the air supply cavity 201 is smaller than the first preset air pressure, the action of controlling the air supply assembly to deliver the oxygen-enriched air to the air supply cavity 201 can be performed after stripping, that is, the forming platform moves upwards, and the oxygen-enriched air is delivered to the air supply cavity 201 when the release film 120 is no longer tightly attached to the supporting surface; in other optional embodiments, the air supply assembly may be controlled to supply air or stop supplying air correspondingly for the first time after the air pressure is detected to be lower than the first preset air pressure or higher than the second preset air pressure.

Optionally, the 3D printing method further includes: the oxygen-enriched gas in the gas supply cavity is controlled to be consumed only through the release film.

Optionally, the 3D printing method further includes: and controlling the consumption rate of the oxygen-enriched gas in the gas supply cavity to be smaller than the preset rate.

The printing material is a light-cured material, and the stripping force is reduced, so that the printing speed can be improved. For high-performance materials, such as dual-curing materials, high-elasticity materials, flexible materials, silica-like materials, high-viscosity materials, two-component materials and the like, under the condition of not using oxygen-enriched gas, the strength is insufficient in the photo-curing stage, and the high-performance materials are easy to break when the stripping force is large, so that the photo-curing 3D printing forming is difficult. In the embodiment of the application, the stripping force is greatly reduced by the oxygen-enriched gas, so that the high-performance material can be printed. Thus, elastic printing pieces such as insoles, pillows and the like can be printed by using the 3D printing method of the embodiment of the application.

In summary, the feeding mechanism provided in the embodiment of the present application includes a tray 100, a supporting structure 200, and a gas supply assembly. The charging tray 100 includes a frame 110 and a release film 120 disposed on the frame 110, openings are disposed at two opposite ends of the frame 110, the release film 120 is sealed at one of the openings of the frame 110, the frame 110 and the release film 120 jointly enclose a containing cavity 101 for containing a printing material, and the release film 120 is light-permeable. The supporting structure 200 is disposed on a side of the release film 120 departing from the accommodating cavity 101, and forms an air supply cavity 201 with an air inlet 202 between the release film 120, the supporting structure 200 has a supporting surface opposite to the release film 120 at an interval, and the supporting surface is light-permeable. The gas supply assembly is in communication with the gas inlet 202 and is used to provide oxygen enriched gas to the gas supply chamber 201. The 3D printer that this application embodiment provided includes shaping platform 500 and the feed mechanism of aforesaid. The 3D printing method provided by the embodiment of the application is applied to the 3D printer, and comprises the steps of controlling the gas supply assembly to supply oxygen-enriched gas to the gas supply cavity 201; the prints are formed layer by layer on the forming platform by exposing the printing material in the tray 100. In the feeding mechanism of the embodiment of the application, the supporting structure 200 and the release film 120 form a gas supply cavity 201 therebetween, the gas supply cavity 201 can accommodate the oxygen-enriched gas provided by the gas supply assembly, and the oxygen in the oxygen-enriched gas can enter the accommodating cavity 101 of the charging tray 100 through the release film 120 to a certain extent. Based on the oxygen inhibition effect of the photo-curable printing material, the adhesive force between the inner surface of the release film 120 and the photo-curable printing layer is reduced to facilitate peeling. Moreover, in this embodiment, when the release film 120 protrudes toward the supporting structure 200 under the action of the gravity of the printing material or the pressure of the forming platform, the supporting surface of the supporting structure 200 can support the release film 120 to a certain extent, so that the release film 120 as the bottom of the tray 100 can be attached to the supporting surface during the printing process, and cannot deform and extend excessively, thereby ensuring the flatness of the forming surface of the release film 120, and improving the printing quality. It can be seen that the feeding mechanism that this application embodiment provided can reduce the adhesion stress of printing layer and charging tray 100 bottom with lower cost to improve the efficiency and the success rate that 3D printed.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a feeding mechanism, is applied to the 3D printer, its characterized in that includes:

the charging tray comprises a frame and a release film, wherein openings are formed in two opposite ends of the frame, the release film is plugged at one opening of the frame, and the frame and the release film jointly enclose a containing cavity for containing printing materials;

the supporting structure is arranged on one side, away from the accommodating cavity, of the release film, an air supply cavity with an air inlet is formed between the supporting structure and the release film, the supporting structure is provided with a supporting surface opposite to the release film at intervals, and the supporting surface is light-permeable; and

2. The feeding mechanism as claimed in claim 1, wherein the distance between the release film and the supporting surface is not more than 5mm.

3. The feed mechanism of claim 1 wherein the gas supply assembly comprises a gas source for storing or preparing an oxygen-enriched gas, the gas source being in communication with the gas inlet.

4. The feed mechanism of claim 3, wherein the oxygen-enriched gas in the gas supply chamber is consumed only through the release film.

5. The feed mechanism of claim 3, wherein the rate of consumption of the oxygen-enriched gas in the gas supply chamber is less than a predetermined rate.

6. The feeding mechanism as claimed in claim 3, wherein the air source is at least one of a disposable oxygen cylinder, a pop can type oxygen cylinder, a snuff type oxygen cylinder, and a mask type oxygen cylinder.

7. The feeding mechanism as defined in claim 3, wherein the gas supply assembly further comprises a pipeline and a speed regulating valve disposed on the pipeline, the gas source is communicated with the gas inlet through the pipeline, and the speed regulating valve is used for regulating the flow rate of the oxygen-enriched gas entering the gas supply chamber.

8. The feed mechanism of claim 7 wherein the gas supply assembly further comprises at least one of a first gas pressure gauge, a second gas pressure gauge, a pressure maintaining valve, a drying duct;

the first air pressure gauge is used for detecting air pressure in the air supply cavity; the second barometer is used for detecting the air pressure in the air source; the pressure stabilizing valve is arranged in the pipeline and is used for outputting the oxygen-enriched gas at a stable air pressure; the drying pipe is arranged in the pipeline.

9. The feeding mechanism as claimed in claim 8, wherein the gas supply assembly further comprises a controller and a solenoid valve disposed in the pipeline, the solenoid valve and the first pressure gauge are both electrically connected to the controller, and the controller is configured to control the on/off of the solenoid valve according to pressure information fed back by the first pressure gauge.

10. The feed mechanism of claim 3, wherein the gas supply assembly further comprises an oxygen concentration sensor for detecting the concentration of oxygen in the gas source or the gas supply chamber.

11. The feeding mechanism of claim 3, wherein the air supply chamber further has an air outlet; the air outlet is communicated with the atmosphere, or the air outlet is communicated with the air source through a pipeline to form a circulating air path.

12. The feeding mechanism as defined in claim 3, wherein the gas source is at least one of an oxygen generator and an oxygen generator.

13. The feeding mechanism as claimed in claim 1, wherein the release film is any one of a fluoropolymer film, a Polydimethylsiloxane (PDMS) film, and a polymethylpentene (PMP) film;

wherein the fluoropolymer membrane is at least one of FEP membrane, nFEP membrane, PTFE membrane, ETFE membrane, PFA membrane, PVDF membrane and PVF membrane.

14. The feeding mechanism according to claim 1, wherein the release film has an oxygen permeability of 0.1barrer or more.

15. The feeding mechanism according to claim 1, wherein the release film has an oxygen permeability of 20barrer or less.

16. The feeding mechanism as claimed in claim 1, wherein at least a partial area of a surface of the release film facing the accommodating chamber is a rough area.

17. The feed mechanism as claimed in claim 1, wherein the support structure comprises a support member, the support member is connected to the tray in a sealing manner, the support surface is formed on the support member, and the air supply cavity is formed between the support surface and the release film.

18. The feed mechanism as claimed in claim 17, wherein the support member is at least one of a transparent glass, an LCD screen, and an LED screen;

the LED screen is any one of OLED, micro-LED, mini-LED, micro-OLED and Mini-OLED.

19. The feeding mechanism as claimed in claim 18, wherein when the supporting member is an LCD panel, the supporting structure further comprises a transparent cover plate, and the transparent cover plate is stacked on a side of the supporting member facing away from the release film.

20. The feeding mechanism as claimed in claim 1, wherein the supporting structure comprises a supporting member and a sealing plate, the sealing plate is spaced from the supporting member, the sealing plate is connected to the tray, the air supply chamber is formed between the sealing plate and the release film, the supporting member is located in the air supply chamber, and the supporting surface is formed on the supporting member.

21. A 3D printer comprising a profiled platform for attaching prints and the feeding mechanism of any of claims 1 to 20, the profiled platform being movable relative to the feeding mechanism to extend into or out of the receiving cavity of the tray.

22. A 3D printing method applied to the 3D printer of claim 21, the 3D printing method comprising:

exposing the printing material in the material tray to form a printing layer adhered on the forming platform;

23. The 3D printing method according to claim 22, wherein in the process of controlling the forming platform to be away from the feeding mechanism to separate the printing layer from the release film, the gas supply assembly is controlled to supply gas to the gas supply cavity to make the release film protrude in a direction away from the support structure.

24. The 3D printing method according to claim 22, wherein the release film is kept in contact with the support surface during the exposure of the printing material in the tray.

25. The 3D printing method of claim 22, wherein during the exposing of the printing material in the tray, the air pressure in the air supply chamber is no more than 1kpa above atmospheric pressure.

26. The 3D printing method according to claim 22, wherein before controlling the forming platform to move away from the feeding mechanism to separate the printed layer from the release film, the 3D printing method further comprises:

detecting the air pressure in the air supply cavity;

under the condition that the air pressure in the air supply cavity is smaller than a first preset air pressure, controlling the air supply assembly to convey the oxygen-enriched air to the air supply cavity;

under the condition that the air pressure in the air supply cavity is greater than a second preset air pressure, controlling the air supply assembly to stop conveying the oxygen-enriched air to the air supply cavity;

27. The 3D printing method of claim 22, wherein the gas supply assembly includes a gas source for storing or preparing an oxygen-enriched gas, the gas source in communication with the gas inlet.

28. The 3D printing method according to claim 27, wherein the 3D printing method further comprises: and controlling the oxygen-enriched gas in the gas supply cavity to be consumed only through the release film.

29. The 3D printing method according to claim 27, wherein the 3D printing method further comprises: and controlling the consumption rate of the oxygen-enriched gas in the gas supply cavity to be smaller than a preset rate.

30. The 3D printing method of claim 27, wherein the gas source is at least one of a disposable oxygen cylinder, a pop can type oxygen cylinder, a snuff type oxygen cylinder, and a mask type oxygen cylinder.