KR20230026603A - Fdm 3d printing apparatus and articles manufactured thereby - Google Patents

Abstract

Provided is a FDM 3D printing device comprising: a printing bed; a nozzle; an extruding unit; a screw; and a cutter. The printing bed provides a space for outputting an output to an upper surface. The nozzle is provided in an upper part of the printing bed, and outputs one or more among a first raw material, a second raw material, or a third raw material to the printing bed. The extruding unit is provided in an upper end of the nozzle, and provides a first inlet for injecting the first raw material in one side, a second inlet for injecting the second raw material or the third raw material in the one side, and a screw which extrudes one or more among the first raw material, the second raw material, or the third raw material. The screw is provided inside the extruding unit, provides an inlet hole for injecting the first raw material in an upper part and an outlet hole for extruding the first raw material in a lower part, and extrudes the first raw material, the second raw material, or the third raw material by rotation. The cutter is provided in an upper end of the extruding unit, and cuts the first raw material. The present invention can manufacture the output with improved strength.

Description

FDM 3D printing device and products manufactured thereby {FDM 3D PRINTING APPARATUS AND ARTICLES MANUFACTURED THEREBY}

The present invention relates to an FDM 3D printing device and a product (output product) manufactured by the device, and more particularly, it is suitable for manufacturing a large-sized product because it can implement a smooth extrusion force even with a large nozzle of 1T or more, 3D printing product It relates to a product with improved physical properties.

3D printing is a technology for forming 3D structural products, and has the advantage of being able to quickly mold 3D structures and also to produce shapes that cannot be assembled/disassembled. 3D printing has long since been studied in earnest, and in the past, 3D printing is limited in materials available for 3D printing, and equipment is expensive, so it is widely used in limited fields such as manufacturing aerospace-related parts or prototypes such as automobiles. Although it has not been done, it has recently been widely used in various fields, and its application area is expanding.

3D printing technology is largely classified into FDM (Fused Deposition Modeling) method using solid material, SLA (Setero Lithography Apparatus) method and DLP (Digital Lighting Processing) method using liquid material, and SLS method using powder type material. (Selective Laser Sintering) method, etc. are being implemented.

Among 3D printing technologies, the FDM method is a method of melting a solid material and then making it like a wire and outputting it through a nozzle.

On the other hand, a high level of mechanical strength is required for outputs obtained by 3D printing devices, and a technology capable of rapidly stacking large-sized outputs is required.

KR 10-2018-0105650 A is a blended yarn containing continuous reinforcing fibers and continuous thermoplastic resin fibers, wherein the dispersion of the continuous reinforcing fibers in the blended yarn is 60 to 100%. A manufacturing method of melting and laminating is disclosed. However, in the case of this invention, correct dispersibility can be maintained, but when the fiber content is increased or the diameter of the filament is increased, the melting of the mixed yarn cannot occur uniformly only under temperature conditions, and it is difficult to realize uniform impregnation of the fibers.

In addition, there is no technology capable of rapidly stacking large-sized output objects using a nozzle of 1T or more.

The matters described as the background art above are only for improving understanding of the background of the present invention, and should not be taken as an admission that they correspond to prior art already known to those skilled in the art.

KR 10-2018-0105650 A

The present invention is intended to provide a 3D printing device optimized for raw materials that can quickly mold an output object while using a large (1T or more) nozzle and improve the physical properties (strength) of the output object and a product manufactured by the same am.

The FDM 3D printing product according to the present invention is a product manufactured by stacking layers by a 3D printing device of the FDM (Fused Deposition Modeling) method, and one unit layer includes a first raw material in the shape of a continuous fiber; a second raw material having a viscosity of 10 ³ Pa·s or less immediately after melting and surrounding the first raw material; T _m (melting temperature) is higher than T _g (Glass Transition Temperature) of the second raw material, the viscosity immediately after melting is 10 ³ Pa·s or more and 10 ⁵ Pa·s or less, and the second raw material surrounding the first raw material is surrounded. includes a third raw material;

The first raw material is glass fiber, carbon fiber, alumina fiber, boron fiber, ceramic fiber, metal fiber, vegetable fiber, aramid fiber, polyoxymethylene fiber, aromatic polyamide fiber, polyparaphenylene benzobisoxazole fiber, polyethylene fiber. It may consist of any one or more of them.

The second raw material may be a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or less immediately after melting.

The third raw material may be a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or more and 10 ⁵ Pa·s or less immediately after melting.

Any one of a dipole bond, a van der Waals bond, a hydrogen bond, or a covalent bond may be formed at the interface between the second raw material and the third raw material.

The FDM method 3D printing apparatus according to the present invention includes a printing bed providing a space in which an output product is output to an upper surface; a nozzle provided above the printing bed and outputting any one or more of the first raw material, the second raw material, or the third raw material to the printing bed; It is provided at the top of the nozzle, a first inlet into which the first raw material is input is provided on one side, and a second inlet into which the second or third raw material is input is provided on one side, and the first or second raw material or the third inlet is provided. An extrusion unit provided with a screw for extruding one or more of the raw materials; It is provided inside the extrusion unit, an input hole through which the first raw material is injected is provided at the top, and a discharge hole through which the first raw material is extruded is provided at the bottom, and the first raw material, the second raw material, or the third raw material is rotated. extruding screw; and a cutter provided at the top of the extrusion unit to cut the first raw material.

A plasma device for inducing a polar functional group on the surface of the second raw material may be provided inside the extrusion unit.

A heater may be provided at a lower end of the printing bed to increase bonding strength between the extruded first raw material, the second raw material, or the third raw material and the printing bed.

The cross section of the nozzle is trapezoidal, the ratio of the lower side to the upper side may be 1:1.5 to 1:5, and the ratio of the lower side to the height may be 1:2 to 1:10.

The first raw material, the second raw material, or the third raw material is output through the output hole of the nozzle, and the diameter of the output hole of the nozzle may be 1T or more.

According to the FDM 3D printing device of the present invention, an output product can be molded quickly while using a large (1T or more) nozzle, and an output product with improved strength can be manufactured.

1 is a view showing a 3D printing device according to an embodiment of the present invention.
Figure 2 is an enlarged view of the extruded portion and the nozzle of the 3D printing device according to an embodiment of the present invention.
Figure 3 shows the positional relationship of the first raw material, the second raw material, and the third raw material.
4 is a cross section of a nozzle.
Figure 5 is a view for explaining that the bonding strength of the interface between the second raw material and the third raw material is chemically and mechanically improved.

Hereinafter, specific contents for solving the above-described objects and problems will be described in detail with reference to the accompanying drawings. On the other hand, in understanding the present invention, if the detailed description of the known technology in the same field is not helpful in understanding the core content of the invention, the description will be omitted, and the technical spirit of the present invention is not limited thereto. and may be modified and implemented in various ways by those skilled in the art.

1 is a view showing a 3D printing apparatus 1000 according to an embodiment of the present invention, and FIG. 2 is an enlarged view of an extrusion unit and a nozzle. 1 and 2, the 3D printing apparatus 1000 according to an embodiment of the present invention is a large area BAAM (Big Area Additive Manufacturing) using a large nozzle, and in a large category, a Fused Deposition Method (FDM) method. Applied to 3D printing devices.

1 and 2, the 3D printing device includes a printing bed 100 providing a space in which an output product is output to the upper surface; and a first raw material S1 or a second raw material provided on the upper side of the printing bed 100 ( S2) or a nozzle 400 for outputting any one or more of the third raw material (S3) to the printing bed 100; is shown.

The printing bed 100 is a means for providing a space in which the output material M is output, and is provided in the form of a plate with a flat upper surface and installed in an open space.

At this time, a heater (not shown) capable of adjusting the temperature of the printing bed 100 may be further provided in the printing bed 100 . The heater is for increasing the bonding strength between the first raw material (S1), the second raw material (S2), or the third raw material (S3) of the first layer stacked first and the printing bed 100, and accordingly, deformation such as warping can prevent

The nozzle 400 is a means for outputting any one or more of the melted first raw material (S1), second raw material (S2), or third raw material (S3) to the printing bed 100, and is a common FDM type 3D printing A nozzle applied to the device may be applied. In particular, in this embodiment, as described below, the second raw material (S2) and the third raw material (S3) are strongly bonded to prevent deformation of the output product during and after molding, so that a nozzle of 1T or more can be applied. there is.

On the other hand, referring to FIGS. 1 and 2, a first inlet 510 into which the first raw material S1 is input is provided on one side, and the second inlet 510 into which the second raw material S2 or the third raw material S3 is input is provided on one side. 2 Inlet 520 is provided, the first raw material (S1), the second raw material (S2), or the third raw material (S3) is provided with a screw 550 for extruding at least one extrusion unit 500; a nozzle is provided at the top of

Specifically, the first feeder 410 is connected to the extrusion unit 500 through a first supply pipe 411 . At this time, the first feeder 410 supplies the first raw material S1 to the extrusion unit 500 through the first supply pipe 411 .

In addition, a second feeder 420 is connected to one side of the extrusion unit 500 through a second supply pipe 412 . At this time, the second feeder 120 supplies the second raw material S2 to the extrusion unit 500 through the second supply pipe 142 .

In addition, a third feeder 430 is connected to one side of the extrusion unit 500 through a third supply pipe 413. At this time, the third feeder 430 supplies the third raw material S3 to the extrusion unit 500 through the third supply pipe 413 .

Further, a heating means 490 for providing heat to the first raw material S1, the second raw material S2, or the third raw material S3 supplied to the extrusion unit 500 is further provided. Thus, the raw material supplied to the extrusion unit 500 is melted or maintained in a molten state by the operation of the heating means 490 . And, the temperature is maintained so that the raw material extruded from the extrusion unit 500 is not cooled too quickly. For example, the heating means 490 maintains the same temperature as the temperature of the raw material extruded from the extrusion unit 500 to maintain the state of the raw material, or maintains a state above the melting temperature of the raw material to maintain the raw material in a molten state. do.

The extrusion of the raw material inside the extrusion unit 500 is by means of the screw 550 provided inside the extrusion unit 500, the screw 550 is provided at intervals from the housing of the extrusion unit 500, through the gap between The second raw material (S2) or the third raw material (S3) is input, and the input second raw material (S2) or the third raw material (S3) is extruded by the rotational force of the screw 550. On the other hand, the first raw material (S1) is introduced into the screw through the input hole 530 provided at the top of the screw 550, and the discharge hole 540 provided at the bottom of the screw 550 by the rotation of the screw 550 is extruded with

On the other hand, a cutter 580 for cutting the first raw material (S1); is provided at the top of the extrusion unit 500. As described above, the first raw material (S1) is extruded by the rotation of the screw 550, and the way to stop the extrusion during 3D printing is to cut the first raw material. Therefore, for smooth cutting, the cutter 580 may be provided in the first inlet 510 at the top of the extrusion part 500 . However, the position of the cutter 580 may be located inside the screw 550 as well as the first inlet 510, and any position that can smoothly cut the first raw material S1 is possible. .

On the other hand, the 3D printing device according to the present invention is optimized for molding an output product by mixing the first raw material (S1), the second raw material (S2), and the third raw material (S3). Specifically, the position (arrangement) relationship of the first raw material (S1), the second raw material (S2), and the third raw material (S3) extruded by the 3D printing apparatus according to the present invention is as shown in FIG.

That is, the first raw material S1 is surrounded by the second raw material S2, and the second raw material S2 is surrounded by the third raw material S3. To achieve such a shape, first, the third raw material (S3) is introduced into the extrusion unit 500. At this time, the third raw material (S3) is supplied as a pellet type raw material. The molten third raw material (S3) is stacked on the printing bed. After the lamination of the third raw material S3 is completed, the first raw material S1 and the second raw material S2 are simultaneously injected into the extrusion unit 500 . Since the first raw material S1 is in the shape of a thin continuous fiber and the second raw material S2 is supplied as a pellet type raw material, the first raw material S1 is extruded into a shape surrounded by the second raw material S2. The nozzle 400 stacks the first raw material S1 surrounded by the second raw material S2 again on top of the stacked third raw material S3, and after the stacking of the first raw material surrounded by the second raw material is completed, the first raw material S1 is stacked. Stacking of the third raw material S3 to surround the second raw material S2 is performed. Through this, the first raw material (S1) has a shape surrounded by the second raw material (S2), and the second raw material (S2) becomes a shape surrounded by the third raw material (S3). One layer composed of the first raw material (S1), the second raw material (S2), and the third raw material (S3) forms one layer of the output.

As described below, a polar functional group can be induced by plasma-treating the surface of the second raw material S2, and the plasma device 560 for plasma-treating the surface of the second raw material S2 is extruded. It may be provided inside the unit.

On the other hand, referring to FIG. 4, the cross section of the nozzle 400 is trapezoidal, the ratio of the lower side L1 and the upper side L2 is 1:1.5 to 1:5, and the lower side L1 and the height L3 are A ratio of 1:2 to 1:10 is preferred. That is, the nozzle 400 may have a shape gradually narrowing from the portion where the first raw material (S1) and the second raw material (S2) meet to the discharged portion, and the first raw material (S1) and the second raw material (S2) Considering the mixing efficiency of , it can be said that it is appropriate to configure the length of the side of the cross section as above.

On the other hand, the nozzle 400 is transferred to the X-axis, Y-axis, and Z-axis from the top of the printing bed 100 by the transfer frame 200, and the first raw material (S1) or the second raw material (S1) in a desired shape and pattern S2) or the third raw material S3 may be output.

At this time, the conveying frame 200 is provided with a conveying member 300 that is conveyed in the X-axis, Y-axis and Z-axis, and the extruding part 500 is sequentially coupled to the conveying member 300, and the nozzle 400 The nozzle 400 is also integrally transferred in the X-axis, Y-axis, and Z-axis directions by the X-axis, Y-axis, and Z-axis direction transfer of the transfer member 300 coupled to the extruded portion.

The transfer frame 200 may be applied in various ways capable of freely transferring the transfer member 300 in the X-axis, Y-axis, and Z-axis directions. For example, the transfer frame 200 may be implemented as a gantry structure.

In other words, the transfer frame 200 includes a pair of X-axis rails 210 provided on both edges of the printing bed 100 and disposed in the X-axis direction; a pair of Z-axis rails 220 disposed on the pair of X-axis rails 210 in the Z-axis direction and transported in the X-axis direction along the X-axis rails 210; Both ends are connected to the pair of Z-axis rails 220 and include Y-axis rails 230 that are transported in the Z-axis direction along the Z-axis rails 220 .

In addition, as the Y-axis rail 230 is provided with a transporter and is transported in the Y-axis direction along the Y-axis rail 230, the transporter 300 moves along the X-axis, Y-axis, and Z-axis from the top of the printing bed 100. It can be freely transferred in the axial direction.

In this case, the transporter 300 may be implemented in the form of a block transported along the Y-axis rail 230 .

Through the above process, a 3D printing product with improved strength can be molded.

The FDM 3D printing product according to the present invention is a product manufactured by stacking layers by a 3D printing device of the FDM (Fused Deposition Modeling) method, and one unit layer includes a first raw material (S1) in the shape of a continuous fiber; A second raw material (S2) having a viscosity of 10 ³ Pa·s or less immediately after melting and surrounding the first raw material (S1); T _m (melting temperature) is higher than T _g (Glass Transition Temperature) of the second raw material (S2), the viscosity immediately after melting is 10 ³ Pa·s or more and 10 ⁵ Pa·s or less, and the first raw material (S1) is A third raw material (S3) surrounding the surrounding second raw material (S2); includes.

An object of the present invention is to improve the strength of an output product through mixing of a first raw material (S1), a second raw material (S2), and a third raw material (S3). Hereinafter, the principle of improving the strength of a product by mixing the first raw material (S1), the second raw material (S2), and the third raw material (S3) will be described.

The first raw material (S1) is glass fiber, carbon fiber, alumina fiber, boron fiber, ceramic fiber, metal fiber, vegetable fiber, aramid fiber, polyoxymethylene fiber, aromatic polyamide fiber, polyparaphenylene benzobisoxazole fiber , It may be made of any one or more of polyethylene fibers.

The fibers used as the first raw material (S1) are lightweight, have high strength and high modulus of elasticity, and when the first raw material (S1) is used in the form of a continuous fiber, the strength of the product can be improved.

On the other hand, the second raw material (S2) should be able to secure the impregnation of the first raw material (S1), and the amount of impregnation should be maximized. Therefore, the second raw material (S2) may be a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or less immediately after melting, and is preferably a thermoplastic (here, immediately after melting means that the raw material is melted and passed through a nozzle). It may be interpreted as meaning right after, and may be interpreted in the same meaning below).

The third raw material S3 is a raw material surrounding the second raw material S2. If the initial viscosity immediately after melting of the third raw material (S3) is too low, it is difficult to implement smooth extrudability, and may be poorly molded by its own weight or external force during the lamination process, and the eccentricity of the first raw material (S1) can happen In addition, even if the initial viscosity is too high, there is a problem in implementing smooth extrudability. Accordingly, the third raw material S3 may be a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or more and 10 ⁵ Pa·s or less immediately after melting, and is preferably a thermoplastic plastic.

In particular, by combining the second raw material (S2) and the third raw material (S3) located in a range where the T _g of the second raw material (S2) is lower than the T _m of the third raw material (S3), the third raw material (S3) The bonding force between the interfaces of the second raw material (S2) and the third raw material (S3) can be improved by enabling the second raw material (S2) to be easily surrounded.

For example, when PEEK (Polyetheretherketone) is used as the second raw material and PC (Polycarbonate) is used as the third raw material, T _g of the second raw material is approximately 144 ° C, T _m is approximately 344 ° C, and the third raw material Since the T _m of is formed at 220 to 280 ° C, when the temperature of the heating means 490 is adjusted to around 300 ° C, the second raw material S2 is in a glass transition state and can sufficiently impregnate the first raw material S1. In addition, the third raw material S3 is completely melted to completely cover and wrap the second raw material S2.

On the other hand, in order to improve the strength of the product, it is necessary to improve the bonding strength of the interface for each raw material. In particular, it is necessary to improve the bonding strength between the interfaces of the second raw material (S2) and the third raw material (S3). Either a bond or a covalent bond may be formed.

Figure 5 is for explaining that the bonding strength of the interface between the second raw material and the third raw material is chemically and mechanically improved.

In particular, the dipole bond can improve the polarity by inducing a number of polar functional groups on the surface of the second raw material (S2), which can be improved by the above-described plasma device 560, the surface of the second raw material (S2) By plasma treatment, a hydrogen bond of O-H is induced between N-H and functional groups such as C=O and COOH, thereby improving bonding strength between the interface between the second raw material (S2) and the third raw material (S3). That is, the bonding strength of the interface is improved through a chemical reaction.

On the other hand, the bonding strength of the interface can be improved by mechanical interfacial bonding. Specifically, after preparing the surface by reducing the surface roughness of the second raw material (S2), when the third raw material (S3) is output, mechanical binding is performed by protrusions formed on the surface of the second raw material (S2), and the second raw material (S2) is produced. It is possible to improve the bonding force between the interface between the raw material (S2) and the third raw material (S3).

Although shown and described in relation to specific embodiments of the present invention, it is known in the art that the present invention can be variously improved and changed without departing from the technical spirit of the present invention provided by the claims below. It will be self-evident to those skilled in the art.

100: printing bed
200: transfer frame
300: conveying body
400: nozzle
500: extrusion part

Claims (10)

As a product manufactured by stacking layers by a 3D printing device of the FDM (Fused Deposition Modeling) method,
One unit layer,
A first raw material in the form of a continuous fiber;
a second raw material having a viscosity of 10 ³ Pa·s or less immediately after melting and surrounding the first raw material;
T _m (melting temperature) is higher than T _g (Glass Transition Temperature) of the second raw material, the viscosity immediately after melting is 10 ³ Pa·s or more and 10 ⁵ Pa·s or less, and the second raw material surrounding the first raw material is surrounded. Is a third raw material; FDM 3D printing product comprising a.
The method of claim 1,
The first raw material is glass fiber, carbon fiber, alumina fiber, boron fiber, ceramic fiber, metal fiber, vegetable fiber, aramid fiber, polyoxymethylene fiber, aromatic polyamide fiber, polyparaphenylene benzobisoxazole fiber, polyethylene fiber. FDM 3D printing product, characterized in that consisting of any one or more of.
The method of claim 1,
The FDM 3D printing product, characterized in that the second raw material is a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or less immediately after melting.
The method of claim 1,
The FDM 3D printing product, characterized in that the third raw material is a thermoplastic or thermosetting plastic having a viscosity of 10 ³ Pa·s or more and 10 ⁵ Pa·s or less immediately after melting.
The method of claim 1,
An FDM 3D printing product, characterized in that any one of a dipole bond, a van der Waals bond, a hydrogen bond, or a covalent bond is formed at the interface between the second raw material and the third raw material.
As a 3D printing device of the FDM method,
A printing bed providing a space for outputting an output to the upper surface;
a nozzle provided above the printing bed and outputting any one or more of the first raw material, the second raw material, or the third raw material to the printing bed;
It is provided at the top of the nozzle, a first inlet into which the first raw material is input is provided on one side, and a second inlet into which the second or third raw material is input is provided on one side, and the first or second raw material or the third inlet is provided. An extrusion unit provided with a screw for extruding one or more of the raw materials;
It is provided inside the extrusion unit, an input hole through which the first raw material is injected is provided at the top, and a discharge hole through which the first raw material is extruded is provided at the bottom, and the first raw material, the second raw material, or the third raw material is rotated. extruding screw; and
FDM 3D printing device comprising a; cutter provided on top of the extrusion unit to cut the first raw material.
The method of claim 6,
The FDM 3D printing device, characterized in that a plasma device for inducing a polar functional group on the surface of the second raw material is provided inside the extrusion unit.
The method of claim 6,
FDM 3D printing apparatus, characterized in that a heater is provided at the bottom of the printing bed to increase the bonding force between the first raw material, the second raw material, or the third raw material to be extruded and the printing bed.
The method of claim 6,
The cross section of the nozzle has a trapezoidal shape, the ratio of the lower side and the upper side is 1: 1.5 to 1: 5, the FDM 3D printing device, characterized in that the ratio of the lower side and the height is 1: 2 to 1: 10.
The method of claim 6,
The first raw material, the second raw material, or the third raw material is output through the output hole of the nozzle, the FDM 3D printing device, characterized in that the diameter of the output hole of the nozzle is 1T or more.

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