CN114619667A - Synchronous pushing and linear stripping device for printing ultrahigh-viscosity resin and resin preparation method - Google Patents

Abstract

The invention discloses a synchronous pushing and line peeling device for printing ultra-high viscosity resin. The device is arranged at the bottom of a photo-curing 3D printing resin tank, and the bottom of the resin tank is provided with a release film. The release film With elasticity, the device includes at least two first rollers and at least two second rollers, and all the at least two second rollers are located between any two of the at least two first rollers, so The at least two second rollers push up the release film toward the 3D printed part, so that the height of the at least two second rollers is lower than the height of the at least two first rollers, and the first roller The release film is closely attached to the second roller to form a concave molding surface. The invention adopts the first roller and the second roller, which can simultaneously cure and peel off the resin, is more suitable for the resin with ultra-high viscosity, and has a wide range of applications.

Description

A synchronous push and line peeling device for printing ultra-high viscosity resin and method for preparing resin

technical field

The invention belongs to the technical field of 3D printing, and in particular relates to a synchronous pushing and line peeling device for printing ultra-high viscosity resin and a method for preparing the resin.

Background technique

3D printing technology has the advantages of short manufacturing cycle and can process parts with complex structure, and has a wide range of application prospects. Among 3D printing technologies, laser lithography (SLA) is the most widely used technology, with a larger printing plane and lower volume shrinkage.

Although there have been a lot of research work and practical application examples of 3D printing photosensitive resin materials, but limited by material properties, the current application of printed parts is still mainly in the stage of model design, prototyping, etc. The performance of the printed parts, In particular, the mechanical properties and heat resistance are far worse than those obtained by injection molding and CNC machine tools, so they have not yet reached the level of practical application.

At this stage, the SLA 3D printing method is top-down. Its working principle is as follows: UV light is driven by a galvanometer to scan the surface of the tank containing the liquid photosensitive resin, activate the polymerization reaction, and the resin hardens to form a three-dimensional object a solid layer. After one layer is built, the platform will drop down a single layer thickness. Then, a doctor blade with vacuum suction is swept across the cross-section of the part, coating it with new material, and on this new liquid surface, the pattern of the subsequent layer is cured by UV light and superimposed on the previous layer. Repeatedly, a complete 3D part can be formed.

SLA 3D printing technology based on the above principles requires the use of a support structure in order to hold the part on the lift table and prevent it from deflecting due to gravity or the lateral pressure of the blade. The traditional 3D printing process needs to go through multiple steps such as the descending of the printing table, light curing, and resin leveling. The key is that, limited by the traditional 3D printing method, the viscosity of the resin must be controlled within 5000cps (Pham, D.T., & Ji, C. (2003). A study of recoating instereolithography. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 217(1), 105-117.), and in the actual production and application process, the The viscosity is generally not higher than 1000cps. If the viscosity is too high, the liquid level will be difficult to spread, and the feedback data of the liquid level sensor will be inaccurate, which will easily cause the bottom fixed lifting platform to dislocate. The liquid surface is uneven, and it is difficult to spread evenly when paving a large area. Therefore, the lower the viscosity of the photosensitive resin that can be used for 3D printing at this stage, the better.

In order to be able to print resins with higher viscosity, the resin is usually coated with a doctor blade, or heated to reduce the viscosity of the resin, or a combination thereof. Patent CN208035377U discloses a light-curing 3D printer with a scraper, which can effectively flatten resin; patent CN210617313U discloses a light-curing 3D printer heating tank, which uses resin heating tank to heat resin; patent CN201721709804.4 Disclosed is a heated scraper blade for a light-curing 3D printer, which uses a scraper blade with a heating function to heat and flatten resin.

The traditional SLA 3D printing technology cannot level high-viscosity resin. At this stage, there are many ways to use scraper-assisted leveling. However, during the leveling process, if the viscosity is too high, the resin will be difficult to level, resulting in printing failure ( Pham, D.T., & Ji, C. (2003). A study of recoating in stereolithography. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 217(1), 105-117.).

From the perspective of the relationship between the molecular structure and properties of the resin, the lower the viscosity of the photosensitive resin means that more reactive diluents should be introduced into the resin system, which will increase the crosslinking density of the resin, making the resin hard and brittle, and not easy to use. Conducive to the further use of the material.

Therefore, the key bottleneck restricting the further development of 3D printing is the performance of materials, and the key to this is that the 3D printing equipment must have a wider processing window and be able to process resins with higher viscosity while maintaining good high molding accuracy to obtain materials with better performance, which can be directly used in actual production.

SUMMARY OF THE INVENTION

In order to improve the above technical problems, the present invention provides a synchronous push and line peeling device for printing ultra-high viscosity resin, the device is arranged at the bottom of a photo-curing 3D printing resin tank, and the bottom of the resin tank is provided with a release film , the release film has elasticity, the device includes at least two first rollers and at least two second rollers, all the at least two second rollers are located at any two of the at least two first rollers. Between one roller, the at least two second rollers push up the release film toward the 3D printed part, so that the height of the at least two second rollers is lower than the height of the at least two first rollers , the release film is closely attached between the first roller and the second roller to form a concave molding surface.

According to an embodiment of the present invention, the device can deform the release film, and then restore the deformation, and the device can simultaneously push and peel off the resin, and at the same time raise the 3D printed part by a layer-thick distance; light-curing 3D printing The laser light source moves synchronously with the device.

According to an embodiment of the present invention, all of the second rollers are located at the center of all of the first rollers.

According to an embodiment of the present invention, a plurality of the first rollers and the second rollers are connected with a translation drive mechanism, and the translation drive mechanism drives the first rollers and the second rollers from one end of the release film to the other. One end translates back and forth. During the translation process, both the first roller and the second roller maintain a sealed state with the outer surface of the release film, and roll along the outer surface of the release film.

According to an embodiment of the present invention, when the release film is translated from one end to the other end, or returned from the other end, both the first roller and the second roller are in a top contact state with the outer surface of the release film .

According to an embodiment of the present invention, the number of the first rollers and the number of the second rollers is even, and the number of the first rollers and the second rollers is 2-8, preferably 2.

According to an embodiment of the present invention, the diameter of the first roller is larger than the diameter of the second roller.

According to an embodiment of the present invention, a plurality of the first rollers are arranged in parallel; and a plurality of the second rollers are arranged in parallel.

According to an embodiment of the present invention, the ejection slit of the laser light source is located at the center of a plurality of second rollers, the area between the plurality of second rollers is the resin exposure area to be cured, and the ejection slit is located at the center of the plurality of second rollers. In the exposure area, the laser light source moves with the movement of the second roller.

According to an embodiment of the present invention, taking the moving direction of the release film from left to right as an example, during the process of pushing the resin by the device, after the resin to be cured is cured in the exposure area, then the first roller on the right moves Continue to move forward and drive the laser to the right. With the deformation of the release film, the first roller and the second mixing wheel on the left separate the cured part of the resin and the release film.

According to an embodiment of the present invention, the translational drive mechanism is a lead screw motor assembly.

According to an embodiment of the present invention, the device includes a base, the base is connected to an external lifting mechanism, and the upper part of the base is used for accommodating the 3D printed part.

According to an embodiment of the present invention, the device is used for peeling the release film from the 3D printed part in a linear scanning manner.

According to an embodiment of the present invention, the viscosity of the uncured resin is not higher than 120 Pas.

The present invention also provides a method for preparing resin using the above device.

According to an embodiment of the present invention, the resin is prepared by simultaneous curing and peeling.

beneficial effect

(1) The traditional method of scraping and heating has a better effect on resins with lower viscosity, but for Newtonian fluids, during the leveling process, resins with higher viscosity are easily subjected to huge shearing by the scraper during the scraping process. The effect of shear force, its paving effect is often poor. The invention adopts the first roller and the second roller to pave the resin, which can be applied to high-viscosity resin, assists the resin to pave, has faster aging, better flatness, and does not produce high-viscosity Newtonian fluid resin. interference, more suitable for printing ultra-high viscosity resins.

(2) The present invention adopts the first roller and the second roller, which can simultaneously cure and peel off the resin, and is more suitable for resin with ultra-high viscosity and has a wide range of applications.

(3) In the process of preparing 3D printed parts, the present application can operate continuously between each layer of printing, without the need to separate the release film and the roller after each layer of printing, which improves the printing efficiency and expands the application field.

(4) The device of the present application isolates oxygen during the printing process, and can be directly used for processing acrylic resins.

Description of drawings

Fig. 1 is the process schematic diagram of preparing ultra-high viscosity resin by synchronous push and line peeling device;

Among them: 1. The first roller; 2. The release film; 3. The exit slit of the laser light source; 4. The base; 5. The second roller; 6. The cured resin.

Detailed ways

The compound of the general formula of the present invention and its preparation method and application will be described in further detail below with reference to specific examples. It should be understood that the following examples are only for illustrating and explaining the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the intended protection scope of the present invention.

Unless otherwise stated, the starting materials and reagents used in the following examples are commercially available or can be prepared by known methods.

Example 1

Fig. 1 is a schematic diagram of the process of preparing ultra-high viscosity resin by synchronous pushing and line peeling device; Fig. 1A is before resin is processed; Fig. 1B is in the process of processing a layer of resin; Fig. 1C is completed after processing a layer of resin.

The device is arranged at the bottom of the photo-curing 3D printing resin tank, and the bottom of the resin tank is provided with a release film 2, and the release film has elasticity.

The thickness of the release film 2 is actually very thin, and for convenience of representation, the thickness of the release film 2 is drawn thicker in the drawings.

The device includes two first rollers 1 arranged in parallel and two second rollers 5 arranged in parallel, the diameter of the first roller is larger than the diameter of the second roller, and the two second rollers 5 are located in two places. between the first rollers 1, and the two second rollers 5 are located in the middle of the two first rollers 1; The height of 5 is lower than the height of the first roller 1 , and the release film 2 is closely attached between the first roller 1 and the second roller 5 to form a concave molding surface.

The two first rollers and the second rollers 5 are both connected to the translational drive mechanism, and the connection mode of the translational drive mechanism is a common method in the prior art, which will not be repeated here. The translation drive mechanism drives the first roller 1 and the second roller 5 to translate back and forth from one end of the release film 2 to the other. The outer surface of the mold film maintains a sealed state and rolls along the outer surface of the release film.

When the release film is translated from one end to the other end, or returned from the other end, both the first roller and the second roller are in a top contact state with the outer surface of the release film.

Specifically, the translational drive mechanism is a screw motor assembly.

The laser light source of photo-curing 3D printing moves synchronously with the device, the exit slit 3 of the laser light source is located at the center between the two second rollers 5, and the area between the two second rollers 5 is to be cured In the resin exposure area, the exit slit 3 of the laser light source is located in the exposure area, and the laser light source moves with the movement of the second roller 5 .

The device can restore the deformation after the release film 2 is deformed. The device can simultaneously push and peel off the resin, and at the same time raise the 3D printed part by a layer-thick distance.

The device includes a base 4, and the base 4 is connected to an external lifting mechanism. The lifting mechanism is a common device in the prior art, which will not be repeated here. The upper part of the base is used to accommodate the 3D printed part. That is, the cured resin 6 .

The device is used for peeling the release film from the cured resin 6 in a linear scanning manner.

The method of preparing resin using synchronous push and peeling device:

As shown in Figure 1, taking the moving direction of the release film from left to right as an example, the two first rollers and the two second rollers move from left to right to drive the deformation of the release film 2 and spread the resin to the base The area between the two second rollers is the area where the uncured resin is used for exposure. The laser passes through the exit slit 3 of the laser light source and just falls to the middle of the second roller 5. During the process of pushing the resin, the to-be-cured After the resin is cured in the exposure area, the first roller on the right continues to move forward, and the laser moves synchronously. Separation membrane. Subsequently, the base 4 is moved down by one layer thickness, the device continues to move from right to left, and the above steps are repeated. In this way, a three-dimensional structure resin stacked layer by layer is prepared.

The resin can be cured and peeled simultaneously.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. The utility model provides a synchronous propelling movement and line stripping off device for printing ultra high viscosity resin, its characterized in that, the bottom in photocuring 3D printing resin groove is located to the device, and the bottom in resin groove is equipped with from the type membrane, from the type membrane elasticity, the device includes two at least first gyro wheels and two at least second gyro wheels, all two at least second gyro wheels are located between two arbitrary first gyro wheels of two at least first gyro wheels, two at least second gyro wheels jack-up the type membrane to 3D printing piece direction, make the height of two at least second gyro wheels is less than the height of two at least first gyro wheels, closely laminate between first gyro wheel and the second gyro wheel from the type membrane, form the profiled surface of indent.

2. The apparatus according to claim 1, wherein the apparatus is capable of recovering the deformation after the release film is deformed, and the apparatus is capable of synchronously pushing and peeling the resin while lifting the 3D print by a thickness of a layer; the laser light source for photocuring 3D printing moves synchronously with the device.

Preferably, all of the second rollers are located at the midpoint of all of the first rollers.

3. The device according to claim 1, wherein the first and second rollers are connected to a translation driving mechanism, the translation driving mechanism drives the first and second rollers to translate back and forth from one end of the release film to the other end of the release film, and the first and second rollers maintain a sealed state with the outer surface of the release film and roll along the outer surface of the release film during translation.

4. The device of claim 1, wherein the first roller and the second roller are in contact with the outer surface of the release film when the release film is translated from one end to the other end or returned from the other end.

Preferably, the number of the first rollers and the number of the second rollers are both an even number, and the number of the first rollers and the number of the second rollers are both 2 to 8, preferably 2.

Preferably, the diameter of the first roller is larger than the diameter of the second roller.

Preferably, a plurality of the first rollers are arranged in parallel; the second rollers are arranged in parallel.

5. The apparatus according to claim 1, wherein the laser light source has an emission slit at a center of a plurality of second rollers, an area between the plurality of second rollers is an exposure area of the resin to be cured, the emission slit is located at the exposure area, and the laser light source moves with the movement of the second rollers.

6. The device of claim 1, wherein the translation drive mechanism is a lead screw motor assembly.

7. The apparatus of claim 1, comprising a base, the base being connected to an external lifting mechanism, the base being adapted to receive the 3D print thereon.

8. The apparatus according to claim 1, wherein the apparatus is configured to peel the release film from the 3D print in a linear scan.

9. The apparatus of claim 1, wherein the uncured resin has a viscosity of no greater than 120 Pas.

10. A method of making a resin using the apparatus of any one of claims 1-9.

Preferably, the resin is prepared by simultaneous curing and stripping.

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