CN113103572A

CN113103572A - Large-breadth digital projection type photocuring 3D printer

Info

Publication number: CN113103572A
Application number: CN202110294155.0A
Authority: CN
Inventors: 王权岱; 叶思彤; 张颖; 高达敬; 袁启龙; 郑建明; 李言
Original assignee: Xian University of Technology
Current assignee: Xian University of Technology
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2021-07-13
Anticipated expiration: 2041-03-19
Also published as: CN113103572B

Abstract

The invention relates to a large-format digital projection type photocuring 3D printer. The method comprises the following steps: a base; the first moving mechanism is arranged on the base; a second moving mechanism which is installed on the first moving mechanism and can move in the X direction through the first moving mechanism; the mounting bracket is mounted on the second moving mechanism, can move in the Y direction through the second moving mechanism and can move in the X direction along with the second moving mechanism through the first moving mechanism; the digital light projector is arranged on the bottom surface of the inner cavity of the mounting bracket; the resin tank is provided with a notch upwards and is arranged at the top of the mounting bracket, a rectangular boss is arranged in the center of the upper surface of the bottom of the resin tank, and a release film is plated on the surface of the rectangular boss; the third moving mechanism is vertically arranged on the base; and the printing platform is arranged on the third moving mechanism and can move in the Z direction through the third moving mechanism, wherein the X direction, the Y direction and the Z direction are mutually vertical.

Description

Large-breadth digital projection type photocuring 3D printer

Technical Field

The invention relates to the technical field of 3D printing, in particular to a large-format digital projection type photocuring 3D printer.

Background

The photocuring forming technology which is used as the earliest process for realizing commercial application in a 3D printing system has the characteristics of high forming precision and high forming speed, and shows wider application potential along with the continuous abundance of composite photosensitive resins such as ABS (acrylonitrile butadiene styrene), heat-resistant resin, ceramic resin and the like in recent years. Digital light projection molding (digital light) completes the molding of the section outline of one part by one-time projection, has the advantages of high molding speed, high precision, high surface smoothness and the like, and is widely applied to the industries of precision casting, aerospace, biomedical treatment and the like. The constrained digital light projection molding is a key research and development direction due to the characteristics of high material utilization rate, small deformation of a workpiece, simple equipment structure and the like.

The main problems existing at present in the constrained digital light projection molding are as follows: (1) due to the projection size of the digital light projector, large-area printing tasks are difficult to complete; (2) too much peeling force when the solidified layer is separated from the constraint substrate can cause printing defects and printing process failure, so that the printing efficiency and the reliability of the process are reduced, and the problem of peeling of the solidified layer is aggravated by large-area printing. Aiming at the problem of limited printing area, researchers propose that a plurality of digital light projectors are adopted for simultaneous projection, mask images projected on the surface of liquid resin by the digital light projectors are controlled to be seamlessly spliced, and the printing area is increased, but the number of the projectors is increased along with the increase of the printing area, the printing cost is too high, and the engineering application is difficult to realize; researchers also propose to realize large-area printing by adopting a single projector by controlling the relative motion among the resin tank, the projector and the printing support plate. However, in constrained digital photo-forming, the peeling force of the cured layer from the substrate increases sharply with the print area, and the current large-area digital photo-printer does not address the process reliability problem caused by the peeling force of the cured layer. In addition, in the scheme using a single projector, the problem of printing accuracy due to the problem of motion synchronization and the problem of parallelism of the projector and the resin tank also need to be solved.

Accordingly, there is a need to ameliorate one or more of the problems with the related art solutions described above.

It is noted that this section is intended to provide a background or context to the embodiments of the invention that are recited in the claims. The description herein is not admitted to be prior art by inclusion in this section.

Disclosure of Invention

An object of the present invention is to provide a large format digital projection photocuring 3D printer that overcomes, at least to some extent, one or more of the problems due to limitations and disadvantages of the related art.

The invention firstly provides a large-format digital projection type photocuring 3D printer, which comprises:

a base;

the first moving mechanism is arranged on the base;

a second moving mechanism which is mounted on the first moving mechanism and can move in the X direction through the first moving mechanism;

the mounting bracket is arranged on the second moving mechanism, can move in the Y direction through the second moving mechanism and can move in the X direction along with the second moving mechanism through the first moving mechanism;

the digital light projector is arranged on the bottom surface of the inner cavity of the mounting bracket;

the resin tank is provided with a notch upwards and is arranged at the top of the mounting bracket, a rectangular boss is arranged in the center of the upper surface of the bottom of the resin tank, and a release film is plated on the surface of the rectangular boss;

the third moving mechanism is vertically arranged on the base;

and the printing platform is arranged on the third moving mechanism and can move in the Z direction through the third moving mechanism, wherein the X direction, the Y direction and the Z direction are mutually vertical.

In an embodiment of the present disclosure, the digital light projector is mounted on the bottom surface of the inner cavity of the mounting bracket through the leveling device.

In one embodiment of the disclosure, the leveling device comprises a leveling plate and leveling screws, the leveling plate is installed on the bottom surface of the inner cavity of the mounting bracket through the leveling screws, and the inclination of the leveling plate is adjusted by adjusting the heights of the leveling screws.

In an embodiment of the present disclosure, the height of the rectangular boss is 0.2mm to 1 mm.

In an embodiment of the present disclosure, the first moving mechanism includes a first motor and an X-direction lead screw assembly; the second moving mechanism comprises a second motor and a Y-direction lead screw component; the third moving mechanism comprises a first motor and a Z-direction lead screw component.

The technical scheme provided by the invention can have the following beneficial effects:

1) the rectangular boss is arranged on the upper surface of the bottom of the resin tank, and the release film is plated on the rectangular boss, so that the problem of process reliability caused by overlarge stripping force of a large-area printing curing layer is solved;

2) the resin tank and the digital light projector are fixed on the same bracket to move synchronously, so that printing errors caused by the problem of synchronous movement of the projector and the resin tank are eliminated;

3) the bottom of the digital light camera is provided with a leveling device, so that the parallelism between the digital light projector and the bottom of the resin tank can meet the requirement.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure. It is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without the exercise of inventive faculty.

Fig. 1 is a schematic structural diagram of a large-format digital projection type photocuring 3D printer according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a resin tank of a large-format digital projection type photo-curing 3D printer according to an embodiment of the invention.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

The embodiment of the invention firstly provides a large-format digital projection type photocuring 3D printer. Referring to fig. 1 and 2, the large format digital projection photocuring 3D printer may include: a base 100, a first movement mechanism 101, a second movement mechanism 102, a mounting bracket 103, a digital light projector 104, a resin vat 105, a third movement mechanism 106, and a print platform 107; the first moving mechanism 101 is mounted on the base 100; the second moving mechanism 102 is mounted on the first moving mechanism 101, and is movable in the X direction by the first moving mechanism 101; the mounting bracket 103 is mounted on the second moving mechanism 102, and is movable in the Y direction by the second moving mechanism 102 and movable in the X direction by the first moving mechanism 101 along with the second moving mechanism 102; the digital light projector 104 is mounted on the bottom surface of the inner cavity of the mounting bracket 103; the notch of the resin groove 105 is upwards arranged at the top of the mounting bracket 103, and a rectangular boss is arranged at the center of the upper surface of the bottom of the resin groove 105; the third moving mechanism 106 is vertically installed on the base 100; the printing platform 107 is mounted on the third moving mechanism 106, and is movable in a Z direction by the third moving mechanism 106, wherein the X direction, the Y direction, and the Z direction are perpendicular to each other. Specifically, the release film is plated on the rectangular boss, the size of the rectangular boss is slightly larger than one exposure breadth, namely the four sides of the rectangular boss are 2mm larger than the four sides of one exposure breadth, so that when the printing platform ascends, only one breadth area of the curing layer is adhered to the upper surface of the rectangular boss in the resin tank in the curing layer stripping process, liquid resin with certain thickness is arranged between the curing layers of other three breadths and the resin tank, and the negative pressure suction force can be basically ignored, so that the stripping force of the curing layer from the resin tank is greatly reduced.

The working principle of the large-format digital projection type photocuring 3D printer is as follows: (1) further dividing and imaging the divided two-dimensional image, and for convenience of description, respectively recording the divided image as an image 1, an image 2, an image 3 and an image 4 from left to right and from top to bottom; (2) moving the digital light projector 104 to a print position and exposing image 1 by the first and

second moving mechanisms

101 and 102; (3) feeding back the position information projected by the digital light projector 104 to the computer; (4) calculating the position of the exposure image 2 to be moved; (5) moving the digital light projector 104 to the print position and exposing the image 2 by the first and

second moving mechanisms

101 and 102; (6) feeding back the position information projected by the digital light projector 104 to the computer; (7) calculating the position of the exposure image 3 to be moved; (8) moving the digital light projector 104 to the print position and exposing the image 3 by the first and

second moving mechanisms

101 and 102; (9) feeding back the position information projected by the digital light projector 104 to the computer; (10) calculating the position of the exposure image 4 to be moved; (11) moving the digital light projector 104 to the print position and exposing the image 4 by the first and

second moving mechanisms

101 and 102; (12) feeding back the position information projected by the digital light projector to a computer; (13) and the third moving mechanism 106 controls the printing platform 107 to move along the Z axis, so that the curing of one section of the part is completed, the part is stripped from the resin tank, and the steps 1 to 13 are repeated until the printing is completed.

According to the large-format digital projection type photocuring 3D printer, the rectangular boss is arranged on the upper surface of the bottom of the resin tank 105, and the release film is plated on the rectangular boss, so that the problem of process reliability caused by overlarge stripping force of a large-area printing curing layer is solved; the resin tank 105 and the digital light projector 104 are fixed on the same mounting bracket 103 to move synchronously, so that printing errors caused by the problem of relative movement between the digital light projector 104 and the resin tank 105 are eliminated.

In one embodiment of the present disclosure, the digital light projector 104 is mounted to the bottom surface of the interior cavity of the mounting bracket 103 via the leveling device 108. Specifically, the bottom of the digital light camera 104 is provided with a leveling device 108, which ensures that the parallelism between the digital light projector 104 and the bottom of the resin tank 105 is satisfactory

In one embodiment, the leveling device 108 includes a leveling plate and a leveling screw, the leveling plate is mounted on the bottom surface of the inner cavity of the mounting bracket through the leveling screw, and the inclination of the leveling plate is adjusted by adjusting the height of the leveling screw.

In one embodiment, the height of the rectangular boss is 0.2mm to 1 mm.

In one embodiment, the release film is a polydimethylsiloxane film. Specifically, the polymerization inhibition effect of oxygen permeating in the polydimethylsiloxane film on the resin can enable an uncured liquid resin thin layer to exist on the surface of the polydimethylsiloxane film, and the polydimethylsiloxane film can play a role of lubricating oil in the transverse moving process of printing of different breadth surfaces of a section, so that the transverse shearing force is obviously reduced.

In one embodiment, the digital light projector 104 has a transmitted light wavelength of 405nm, an exposure uniformity of 85% or more, an accuracy of 50 μm, a distortion of < 0.8%, and a maximum projection aspect of 131.2mm by 82 mm.

In one embodiment, the first moving mechanism 101 includes a first motor and an X-direction lead screw assembly; the second moving mechanism 102 comprises a second motor and a Y-direction lead screw assembly; the third moving mechanism 106 includes a first motor and a Z-direction lead screw assembly.

It is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like in the foregoing description are used for indicating or indicating the orientation or positional relationship illustrated in the drawings, and are used merely for convenience in describing embodiments of the present invention and for simplifying the description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the embodiments of 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 of that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In embodiments of the invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise the first and second features being in direct contact, or the first and second features being in contact, not directly, but via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," 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 are not necessarily intended to 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. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

1. The utility model provides a big breadth digital projection formula photocuring 3D printer which characterized in that includes:

a base;

the first moving mechanism is arranged on the base;

the third moving mechanism is vertically arranged on the base;

2. The large format digital projection photocuring 3D printer of claim 1, wherein the digital light projector is mounted on the bottom surface of the mounting bracket cavity via the leveling device.

3. The large format digital projection photocuring 3D printer of claim 2, wherein the leveling device comprises a leveling plate and leveling screws, the leveling plate is mounted on the bottom surface of the inner cavity of the mounting bracket through the leveling screws, and the inclination of the leveling plate is adjusted by adjusting the heights of the leveling screws.

4. The large format digital projection photocuring 3D printer of claim 1, wherein the height of the rectangular boss is 0.2mm to 1 mm.

5. The large format digital projection photocuring 3D printer of any one of claims 1-5, wherein the first movement mechanism comprises a first motor and an X-direction lead screw assembly; the second moving mechanism comprises a second motor and a Y-direction lead screw component; the third moving mechanism comprises a first motor and a Z-direction lead screw component.