Release-film-free photocuring 3D printer

Abstract

The utility model discloses a release-film-free photocuring 3D printer which comprises a printer body. A printing platform; the release-film-free trough system comprises: a trough-shaped structure having a transparent bottom plate; the lower isolation plate is fixedly arranged in the groove-shaped structure, a first space for containing isolation liquid is formed between the lower isolation plate and the bottom surface of the groove-shaped structure, the lower isolation plate extends upwards in the circumferential direction to form a construction groove, and a first hole is formed in the lower isolation plate; the upper isolation plate is rotatably arranged in the construction groove, the upper surface of the lower isolation plate is attached to the lower surface of the upper isolation plate, and a second hole is formed in the upper isolation plate; the driving mechanism is linked with the isolation upper plate; the light source system is arranged in the machine body, an irradiation light path of the light source system and the first hole are located on the same axis, photosensitive resin forms a three-dimensional object on the printing platform through light reaction, a double-liquid interface between spacer fluid and the photosensitive resin is formed through a special resin groove, and a release film is omitted. And problems caused by release of the release film are avoided.

Description

Technical Field

[0001] The utility model relates to a 3D printing device, in particular to a release film-free light-curing 3D printer. Background Art

[0002] Because of its high precision and high speed, photocuring 3D printing technology has been widely used in various fields for product development and manufacturing. The working principle of photocuring 3D printing technology is to irradiate a specific optical pattern on the surface of the photosensitive resin, selectively crosslink and cure it by inducing a crosslinking and curing reaction, and then stack it layer by layer to form an object with a three-dimensional structure. According to the different light sources, the main methods of photocuring 3D printing currently include SLA (stereolithography), DLP (digital light processing) and LCD (liquid crystal display). According to the model forming method, photocuring 3D printing is divided into two types: top-down and bottom-up. In the former, the light source is located above the resin tank, and curing starts from the top. For each cured layer, the printing platform will move downward; in the latter, the light source irradiates from the bottom of the resin tank upward, and curing starts from the bottom. After each layer is cured, the printing platform moves up one layer. The former requires dynamic monitoring of the liquid level, and then scraping the liquid level with a scraper; while the latter relies on gravity to make the photosensitive resin flow, so there is no need to scrape the liquid level; and the top-up model can leave the resin tank, so the amount of resin required is greatly reduced.

[0003] However, because pull-up printing requires a special release film, it is easy to cause the printed part to be difficult to release and cause product printing failure. For example, Chinese patent 201480008397.7 mentions a special oxygen-permeable release film that uses oxygen to form an inhibitor layer, which can greatly reduce the release force and even achieve continuous printing. However, this special oxygen-permeable release film is very expensive and easily causes deformation of the molding surface, which limits the large-scale application of this technology.

[0004] The top-type light-curing 3D printer requires less resin to work, and the molding process does not need to monitor the liquid level changes. Therefore, compared with the bottom-type light-curing 3D printer, it has the advantages of low cost, good precision, and high efficiency. However, due to the existence of the release film during the printing process, a certain draft force is required, which can easily lead to delamination, board drop and other problems, which can easily lead to model damage, thereby reducing the printing success rate. The use of special oxygen-permeable release film, which uses oxygen to form an inhibitor layer, can greatly reduce the release force, but because it is very expensive and easily causes deformation of the molding surface, it limits the large-scale application of this technology. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a release film-free light-curing 3D printer.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A release film-free light-curing 3D printer, comprising:

[0008] a fuselage, the upper surface of which is provided with a support body;

[0009] A printing platform is slidably disposed on the support body along the Z-axis direction, and forms the three-dimensional object on the printing platform;

[0010] The free release film material tank system is arranged between the upper surface of the machine body and the printing platform, and comprises:

[0011] A trough-like structure having a transparent bottom plate;

[0012] An isolation lower plate, which is fixedly placed in the groove-shaped structure and forms a first space for containing isolation liquid between the isolation lower plate and the bottom surface of the groove-shaped structure. The isolation lower plate extends upward in a circumferential direction to form a building groove for containing photosensitive resin. The isolation lower plate is provided with a first hole communicating with the first space;

[0013] The isolation upper plate is rotatably arranged in the building groove, and the upper surface of the isolation lower plate is arranged in contact with the lower surface of the isolation upper plate, and the isolation upper plate is provided with a second hole;

[0014] A driving mechanism is arranged in linkage with the isolation upper plate, and has a function of driving the isolation upper plate to rotate so that the second hole is partially or completely overlapped with the first hole in a first state and a second state so that the second hole does not overlap with the first hole;

[0015] A light source system is arranged in the body, and the irradiation light path of the light source system is on the same axis as the first hole, and the photosensitive resin forms a three-dimensional object on the printing platform through light reaction,

[0016] By rotating the isolation upper plate relative to the isolation lower plate, an isolation double liquid interface of the isolation liquid and the photosensitive resin is generated layer by layer.

[0017] The groove-shaped structure cooperates with the lower isolation plate to form a sealing structure, and an isolation liquid inlet and an isolation liquid outlet communicating with the first space are provided on the outer side of the building groove.

[0018] Preferably, the release-free film material tank system further comprises an isolation liquid circulation mechanism, which is respectively connected to the isolation liquid inlet and the isolation liquid outlet.

[0019] Preferably, the support body is a Z-axis slide, and the printing platform is slidably arranged on the Z-axis slide via a cantilever.

[0020] Preferably, the light source system is a DLP or LCD light source.

[0021] Preferably, the first hole and the second hole are circular or rectangular and have the same size.

[0022] Preferably, the thickness of the insulating lower plate is 50 microns to 2000 microns.

[0023] Preferably, the distance between the isolation lower plate and the transparent bottom plate is 50 microns to 2000 microns.

[0024] The beneficial effects of the utility model are as follows: a double liquid interface between the isolation liquid and the photosensitive resin is formed through a special resin tank, thereby eliminating the release film and avoiding the problems caused by the release of the release film.

[0025] 1) Realize the pull-up light-curing 3D printing without release film, effectively solve the problem of difficult release of printed parts, and greatly improve the printing success rate and printing efficiency of printed parts.

[0026] 2) Because the molding surface height is fixed, the problem of requiring a large amount of resin for the sinking type can also be avoided.

[0027] 3) When the components of the isolation liquid and the photosensitive resin are basically the same except for a trace amount of inhibitor, after the isolation interface is formed, even if a small amount of isolation liquid enters the photosensitive resin, it will not cause contamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the three-dimensional structure of the whole machine of the utility model;

[0029] Figure 2 This is a schematic diagram of the three-dimensional structure of the release film-free resin tank of the present invention;

[0030] Figure 3 It is a schematic diagram of the configuration of the release film-free resin tank of the utility model when the isolation liquid level is closed;

[0031] Figure 4 This is a schematic diagram of the structure of the utility model when the release film-free resin tank is opened to isolate the liquid level;

[0032] In the figure: 10, Z-axis slide, 12, cantilever, 15, printing platform, 18, three-dimensional object, 26, resin tank, 28, isolation double liquid interface, 27, transparent bottom plate, 30, body, 31, light source, 32, controller, 35, working platform, 40, rotating isolation upper plate, 41, isolation lower plate, 45, isolation liquid inlet, 46, isolation liquid outlet, 50, photosensitive resin layer, 51, isolation liquid. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0035] The utility model provides a release-free film light-curing 3D printer, which comprises a printing platform lifting system, a release-free film material slot system, a light source system and a controller.

[0036] The basic principle is to utilize the relative rotational movement of the isolation upper plate and the lower plate of the release film-free resin tank, which are continuously opened and closed, to generate the isolation double liquid interface between the isolation liquid and the photosensitive resin layer by layer; because the isolation liquid is a photosensitive resin containing an inhibitor or without an initiator, it does not undergo a curing reaction under light, so the double liquid interface can replace the release film as the solid-liquid separation molding surface during printing. Because the isolation liquid and the photosensitive resin have basically the same composition, even if a small amount of photosensitive resin enters the isolation liquid, the composition can be basically unchanged due to the continuous circulation and renewal of the isolation liquid. If a small amount of isolation liquid enters the photosensitive resin, it will also be diluted by the photosensitive resin or the inhibitor it contains will decompose under light. Therefore, the isolation liquid and the photosensitive resin will not cause cross contamination.

[0037] The printing platform lifting system includes a body 30, a Z-axis slide 10, a cantilever 12, and a printing platform 15. The printing platform is connected to the cantilever, and the cantilever is fixed on a slider of the Z-axis slide, and the Z-axis slide drives the printing platform to move up and down. That is, the slider on the Z-axis slide drives the printing platform to move up and down under the control of the controller 32.

[0038] The upper surface of the machine body is provided with a support body, and the upper surface of the machine body is set as a working platform 35. The printing platform lifting system and the release-free film material slot system are arranged above the working platform.

[0039] The printing platform can be slidably disposed on the support body along the Z-axis direction, and the three-dimensional object is formed on the printing platform.

[0040] The release film-free material slot system is arranged between the upper surface of the machine body and the printing platform, and is composed of a slot-shaped structure, a transparent bottom plate 27 , an isolation upper plate 40 , and an isolation lower plate 41 .

[0041] The groove-like structure is a resin groove 26, which has a transparent bottom plate 27, so that the light of the light source system can enter the groove-like structure through the transparent bottom plate.

[0042] The isolation lower plate is fixedly placed in the groove structure and forms a first space for accommodating the isolation liquid 51 between the isolation lower plate 41 and the bottom surface of the groove structure. The isolation lower plate 41 extends upward in a circumferential direction to form a building groove for accommodating the photosensitive resin 25. The isolation lower plate is provided with a first hole connected to the first space.

[0043] The isolation upper plate 40 can be rotatably disposed in the construction groove, and the upper surface of the isolation lower plate is disposed in contact with the lower surface of the isolation upper plate, and the isolation upper plate is provided with a second hole.

[0044] The driving mechanism is a motor, which is linked to the isolation upper plate and has the function of driving the isolation upper plate to rotate so that the second hole is partially or completely overlapped with the first hole in a first state and the second hole is not overlapped with the first hole in a second state.

[0045] At the beginning of each layer of printing, the printing platform 15 descends to the molding distance, the isolation upper plate is driven to rotate by the driving mechanism, the free release film material tank system is opened, and the liquid photosensitive resin contacts the isolation liquid to form an isolation double liquid interface 28. The photosensitive resin layer 50 above the isolation double liquid interface undergoes a photocuring reaction, and the upper end is cured to the surface of the printing platform; and because the isolation liquid layer does not react under light, the lower end is cured to the isolation double liquid interface and terminates, forming a solid-liquid interface. The printing platform 15 rises, the isolation upper plate rotates, and the free release film material tank system is closed to prepare for the next cycle. Each time the printing platform 15 rises, the three-dimensional object after the previous curing is placed on the upper surface of the photosensitive resin, thereby achieving layer-by-layer printing.

[0046] The light source system 31 is located below the free-release resin tank and is disposed in the body, and the irradiation light path of the light source system is on the same axis as the first hole, and the photosensitive resin forms a three-dimensional object on the printing platform through photoreaction. Under the control of the controller 32, the light source system generates an optical pattern that can trigger a photoreaction, so that the photosensitive resin is cured layer by layer and stacked layer by layer to obtain a three-dimensional object 18.

[0047] Because of the existence of the non-reactive area of ​​the isolation liquid below the isolation double-liquid interface, there is no demolding resistance when the printing platform rises, so the solid (printing object) and liquid (photosensitive resin) separation can be smoothly achieved, and the printing success rate can be greatly improved.

[0048] The release-free film material tank system also includes an isolation liquid circulation mechanism, which introduces fresh isolation liquid from the isolation liquid inlet 45 and then discharges it from the isolation liquid outlet 46. The purpose of this is to keep the composition of the isolation liquid consistent, avoid the isolation liquid from solidifying under the action of light curing, and protect the isolation double liquid interface 28 from damage.

[0049] Moreover, the isolation liquid is a photosensitive resin containing an inhibitor or not containing an initiator, and the inhibitor is any one of oxygen, hydroquinone, p-benzoquinone, etc. The initiator is any one of photoinitiator TPO, photoinitiator 819, etc. The photosensitive resin in the isolation liquid has the same composition as the molding photosensitive resin in the resin tank, the photoinitiator TPO is diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, and the photoinitiator 819 is phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0050] Preferably, the thickness of the insulating lower plate is 50 microns to 2000 microns.

[0051] Preferably, the distance between the isolation lower plate and the transparent bottom plate is 50 microns to 2000 microns.

[0052] The embodiments should not be regarded as limiting the present invention, but any improvements based on the spirit of the present invention should be within the protection scope of the present invention.

Claims

1. A release film-free light-curing 3D printer, characterized in that: It includes: a fuselage, the upper surface of which is provided with a support body; A printing platform is slidably disposed on the support body along the Z-axis direction, and a three-dimensional object is formed on the printing platform; The free release film material tank system is arranged between the upper surface of the machine body and the printing platform, and comprises: A trough-like structure having a transparent bottom plate; An isolation lower plate, which is fixedly placed in the groove-shaped structure and forms a first space for containing isolation liquid between the isolation lower plate and the bottom surface of the groove-shaped structure. The isolation lower plate extends upward in a circumferential direction to form a building groove for containing photosensitive resin. The isolation lower plate is provided with a first hole communicating with the first space; The isolation upper plate is rotatably arranged in the building groove, and the upper surface of the isolation lower plate is arranged in contact with the lower surface of the isolation upper plate, and the isolation upper plate is provided with a second hole; A driving mechanism is arranged in linkage with the isolation upper plate, and has a function of driving the isolation upper plate to rotate so that the second hole is partially or completely overlapped with the first hole in a first state and a second state so that the second hole does not overlap with the first hole; A light source system is arranged in the body, and the irradiation light path of the light source system is on the same axis as the first hole, and the photosensitive resin forms a three-dimensional object on the printing platform through light reaction, By rotating the isolation upper plate relative to the isolation lower plate, an isolation double liquid interface of the isolation liquid and the photosensitive resin is generated layer by layer.

2. A release film-free light-curing 3D printer according to claim 1, characterized in that: The groove-shaped structure cooperates with the lower isolation plate to form a sealing structure, and an isolation liquid inlet and an isolation liquid outlet communicating with the first space are provided on the outer side of the building groove.

3. A release film-free light-curing 3D printer according to claim 2, characterized in that: The release-free film material tank system also includes an isolation liquid circulation mechanism, which is respectively connected to the isolation liquid inlet and the isolation liquid outlet.

4. A release film-free light-curing 3D printer according to claim 1, characterized in that: The support body is a Z-axis slide, and the printing platform is slidably arranged on the Z-axis slide via a cantilever.

5. The release film-free light-curing 3D printer according to claim 1, characterized in that: The light source system is a DLP or LCD light source.

6. The release film-free light-curing 3D printer according to claim 1, characterized in that: The first hole and the second hole are circular or rectangular and have the same size.

7. The release film-free light-curing 3D printer according to claim 1, characterized in that: The thickness of the isolation lower plate is 50 microns to 2000 microns.

8. The release film-free light-curing 3D printer according to claim 1, characterized in that: The distance between the isolation lower plate and the transparent bottom plate is 50 microns to 2000 microns.

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