WO2021015416A1

WO2021015416A1 - Quantitative powder applying device and three-dimensional printer including same

Info

Publication number: WO2021015416A1
Application number: PCT/KR2020/007674
Authority: WO
Inventors: 배성우; 김해정
Original assignee: 주식회사 에스에프에스
Priority date: 2019-07-19
Filing date: 2020-06-12
Publication date: 2021-01-28
Also published as: KR102078812B1

Abstract

The present invention relates to a quantitative powder applying device, which can mold a three-dimensional sculpture, and a three-dimensional printer including same. The quantitative powder applying device may comprise: a powder hopper for storing therein a powder material for a three-dimensional printer; a powder supply control unit which is installed so as to be connected to a lower portion of the powder hopper, receives the powder material stored in the powder hopper, and can control the amount of the powder material supplied from the powder hopper by controlling the rotation amount of a screw shaft rotating therein; and a re-coater unit which is installed to be able to reciprocate on a pair of rails mounted to the upper surface of a worktable of the three-dimensional printer, applies the powder material, received from the powder supply control unit, on the upper surface of the worktable while moving in one direction, and presses the powder material, applied on the upper surface of the worktable, to a uniform height while moving in the opposite direction to the one direction.

Description

Powder quantitative application device and 3D printer including same

The present invention relates to a powder quantitative coating apparatus and a 3D printer including the same, and more particularly, to a powder quantitative coating apparatus capable of sculpting a three-dimensional sculpture and a 3D printer including the same.

3D printing technology refers to a manufacturing technology that creates an article as if printing in a 3D space based on a 3D drawing. At the beginning of development, it was limited to plastic materials and was used for a limited purpose, but the range has been expanded to nylon and metal, and it is being applied to all industrial fields to the extent that it can print cell phone cases and automobile accessories.

In general, most industrial metal 3D printers follow the selective laser sintering (SLS) method, in which metal powder is applied and only the desired part is melted with a laser to make a product. However, the selective laser sintering method has the disadvantage that it is possible to manufacture elaborate products, but it is difficult to manufacture large products and the production speed is slow. Accordingly, in recent years, a binder-jet method in which a product is made by applying metal or plastic powder on a stage of a modeling box and spraying an adhesive on a desired portion has emerged. The binder jet method has the advantage of being able to print a large number of products at a faster speed, and that the product size constraints are less than that of the SLS method.

However, in the conventional 3D printer using the binder jet method, the powder material is applied on the molding stage of the modeling box, and then the blade is moved in one direction to flatten it. Since it only functions to spread the powder material accumulated higher than the lower surface of the blade while passing through the upper side, the powder material does not spread evenly, and the density of the dispersed powder material is very low.

Accordingly, when a three-dimensional sculpture is molded because the amount of the powder material dispersed by each part on the molding stage is different, the surface state of the three-dimensional sculpture is not accurately formed, and a large number of voids are generated between the powder and the powder, thereby increasing the strength of the three-dimensional sculpture. There was a falling problem.

The present invention is to solve various problems, including the above problems, by applying a quantitatively weighed powder material on the molding stage of a molding box, and pressing the applied powder material to a uniform height on the molding stage. An object of the present invention is to provide a powder quantitative coating apparatus capable of increasing the precision and strength of a three-dimensional object to be formed by uniformly spreading at a high density, and a 3D printer including the same. However, these problems are exemplary, and the scope of the present invention is not limited thereby.

According to an embodiment of the present invention, an apparatus for quantitatively applying powder of a 3D printer is provided. The apparatus for quantitatively applying powder of the 3D printer includes: a powder hopper in which a powder material for a 3D printer is stored; Powder which is installed to be connected to the lower part of the powder hopper to supply the powder material stored in the powder hopper, and to control the amount of the powder material supplied from the powder hopper by adjusting the amount of rotation of the screw shaft rotating inside Supply regulator; And reciprocally installed on a pair of rails installed on the upper surface of the work table of the 3D printer to apply the powder material received from the powder supply control unit while moving in one direction to the upper surface of the work table, opposite to the one direction. It may include; a recoater unit for pressing the powder material applied to the upper surface of the work table to a uniform height while moving in the other direction.

According to an embodiment of the present invention, the powder hopper may include a hopper body formed in an inverted pyramid shape with an open upper side; And a powder supply port formed on the lower surface of the hopper body.

According to an embodiment of the present invention, the powder supply control unit is formed to extend long in the width direction of the work table, and one side is installed at a position corresponding to the position of the powder supply port, and the powder supplied from the powder hopper A measuring chamber in which an upper open inner space for receiving a material is formed; The screw shaft rotatably installed in the inner space of the measuring chamber and having a spiral wing portion formed on the outer diameter surface; Supports rotatably supporting the measuring chamber on both sides of the measuring chamber; And a driving cylinder installed at the rear side of the measuring chamber to be connected to an upper rear surface of the measuring chamber, and rotating the measuring chamber in the direction of the recoater installed in front of the measuring chamber by a linear driving force having a variable length. Can include.

According to an embodiment of the present invention, the measuring chamber may be formed to be inclined toward the recorder unit as the front surface thereof goes upward.

According to an embodiment of the present invention, the powder supply control unit includes: a driving motor installed on one side of the support unit to apply a driving force to rotate the screw shaft; And a controller that is electrically connected to the drive motor and controls the drive motor according to the set supply amount of the powder material to control the number of rotations of the screw shaft.

According to an embodiment of the present invention, the recoater unit is formed to be elongated to a length corresponding to the length of the measuring chamber, so that an upper open inner space for receiving the powder material received from the measuring chamber is formed. And a supply chamber in which a coating slit capable of applying the powder material downward is formed on a lower surface thereof; And a feeding roller which is rotatably installed in a position corresponding to the coating slit in the inner space of the supply chamber, and applies the powder material through the coating slit by rotation.

According to an embodiment of the present invention, the feeding roller may have a plurality of feeding grooves formed along an outer circumferential surface.

According to an embodiment of the present invention, the recoater unit may further include a stirring roller which is rotatably installed in the inner space of the supply chamber and stirs the powdered material accommodated in the supply chamber by rotation. .

According to an embodiment of the present invention, the stirring roller may have a plurality of protrusions formed to protrude in a bolt shape on an outer circumferential surface.

According to an embodiment of the present invention, the recoater unit is rotatably installed on one side of the outside of the supply chamber, and a recoating roller for pressing the powder material applied by rotation to a uniform height; further comprises can do.

According to another embodiment of the present invention, a three-dimensional printer is provided. The 3D printer is formed in a box shape with an open top so that an interior space in which a powder material can be accommodated and a three-dimensional sculpture can be formed, and is provided to be elevating and descending inside the three-dimensional sculpture on the upper surface. A sculpting box including a sculpting stage that is stacked and shaped in layers of; A body in which a modeling box receiving part in which the modeling box is accommodated is formed; A powder coating device installed on one side of the upper portion of the body and quantitatively applying the powder material so that a powder layer having a predetermined thickness may be formed on the molding stage of the molding box accommodated in the molding box receiving portion; A printing device installed on the other side of the upper portion of the body and spraying an adhesive material onto the powder layer applied on the molding stage in an inkjet manner; And an elevating device installed below the modeling box receiving part to lift the modeling stage of the modeling box.

According to an embodiment of the present invention made as described above, a quantitatively weighed powder material is applied on the molding stage of the modeling box, and the applied powder material is pressed to a uniform height to achieve a high density uniformly on the molding stage. By making it spread so that it is possible to implement a powder quantitative coating device and a 3D printer including the same, which can increase the precision and strength of the three-dimensional sculpture to be shaped. Of course, the scope of the present invention is not limited by these effects.

1 is a perspective view schematically showing a 3D printer according to an embodiment of the present invention.

2 and 3 are perspective and cross-sectional views schematically illustrating a powder quantitative coating apparatus of the 3D printer of FIG. 1.

4 and 5 are perspective views illustrating an operating state of a powder hopper and a powder supply control unit of the powder quantitative coating apparatus of FIG. 2.

6 and 7 are front and rear perspective views schematically showing a recoater unit of the powder quantitative coating apparatus of FIG. 2.

8 is a perspective view schematically illustrating a feeding roller of the recoater of FIG. 6.

9 is a perspective view schematically showing the stirring roller of the recoater of FIG. 6.

10 and 11 are cross-sectional views illustrating an operating state of the powder supply control unit based on the cross-section taken along the cut line A-A of FIG. 3.

12 to 14 are cross-sectional views schematically illustrating a process of shaping a three-dimensional sculpture in an inner space of the modeling box of the 3D printer of FIG. 1.

Hereinafter, various exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are provided to more completely describe the present invention to those of ordinary skill in the art, and the following examples may be modified in various other forms, and the scope of the present invention is as follows. It is not limited to the examples. Rather, these embodiments are provided to make the present disclosure more faithful and complete, and to completely convey the spirit of the present invention to those skilled in the art. In addition, in the drawings, the thickness or size of each layer is exaggerated for convenience and clarity of description.

Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically showing ideal embodiments of the present invention. In the drawings, for example, depending on manufacturing techniques and/or tolerances, variations of the illustrated shape can be expected. Accordingly, the embodiments of the inventive concept should not be construed as being limited to the specific shape of the region shown in the present specification, but should include, for example, a change in shape caused by manufacturing.

1 is a perspective view schematically showing a 3D printer 1000 according to an embodiment of the present invention, and FIGS. 2 and 3 schematically illustrate a powder quantitative coating apparatus 100 of the 3D printer 1000 of FIG. 1 4 and 5 are perspective views showing an operating state of the powder hopper 10 and the powder supply control unit 20 of the powder quantitative coating apparatus 100 of FIG. 2. 6 and 7 are front and rear perspective views schematically showing the recorder unit 30 of the powder quantitative coating apparatus 100 of FIG. 2, and FIGS. 8 and 9 are feeding rollers of the recorder unit 30 of FIG. 6 A perspective view schematically showing 32 and the stirring roller 33, and FIGS. 10 and 11 are cross-sectional views illustrating an operating state of the powder supply control unit 20 based on a cross section taken along the perforation line AA of FIG. 3.

First, as shown in FIG. 1, the 3D printer 1000 according to an embodiment of the present invention includes a powder quantitative coating device 100, a body 200, a modeling box 300, and a printing device. It may include 400 and the elevating device 500.

As shown in Fig. 1, the modeling box 300 is formed in a box shape with an open upper side so that the powder material M is accommodated to form an inner space in which a three-dimensional sculpture A can be formed, It may include a sculpting stage 310 in which a three-dimensional sculpture A is stacked in a plurality of layers on the upper surface to be formed so as to be elevated inside.

In addition, the body 200 has a molding box receiving unit 210 in which the molding box 300 is accommodated, and a powder quantitative coating device 100 and a printing device 400 are installed and supported on the upper surface thereof. It may be a kind of frame structure that can be done. For example, the body 200 may be an integral injection structure, a casting, or a frame structure formed by welding or connecting various shapes of plate, wire, pipe, vertical member, horizontal member, and inclined member to each other.

The powder quantitative coating device 100 is installed on one side of the upper portion of the body 200, and a powder layer having a predetermined thickness is formed on the sculpting stage 310 of the sculpting box 300 accommodated in the sculpting box receiving part 210. The powder material (M) may be applied in a quantity so that it can be formed.

In addition, the printing device 400 is installed on the other side of the upper portion of the body 200 and has a printing head PH that can move in the XY axis on the working stage of the body 200, A liquid adhesive material may be sprayed onto the applied powder layer in an inkjet manner. In addition, the elevating device 500 may be installed under the modeling box receiving unit 210 to elevate and lower the modeling stage 310 of the modeling box 300.

As shown in Figs. 2 and 3, the powder quantitative coating apparatus 100 of the three-dimensional printer 1000 includes a powder hopper 10, a powder supply control unit 20, and a recoater unit 30. Can include.

For example, the powder hopper 10 may store a powder material M for the 3D printer 1000 therein. More specifically, the powder hopper 10 may include a hopper body 11 formed in an inverted pyramid shape with an open top and a powder supply port 12 formed on a lower surface of the hopper body 11.

In addition, the powder supply control unit 20 is installed to be connected to the lower portion of the powder hopper 10 to supply the powder material (M) stored in the powder hopper 10, and the rotation of the screw shaft 22 rotating therein. The amount of the powder material M supplied from the powder hopper 10 can be controlled by adjusting the total amount.

More specifically, as shown in FIG. 4, the powder supply control unit 20 is formed to extend in the width direction of the work table T of the 3D printer 1000 so that one side thereof is the powder supply port 12 The measuring chamber 21 is installed in a position corresponding to the position of the powder hopper 10 and an upper open inner space for receiving the powder material M supplied from the powder hopper 10 is formed, and the inner space of the measuring chamber 21 The screw shaft 22 is rotatably installed on the outer diameter surface and has a helical wing portion formed on the outer diameter surface, and the support 23 rotatably supporting the measuring chamber 21 on both sides of the measuring chamber 21, and the measuring chamber ( It is installed to be connected to the upper rear side of the measuring chamber 21 from the rear side of the measuring chamber 21, and the measuring chamber 21 is moved in the direction of the recoater unit 30 installed in the front of the measuring chamber 21 by a linear driving force of varying length. It may include a drive cylinder 24 to rotate.

Therefore, the powder supply control unit 20, when the screw shaft 22 inside the measuring chamber 21 rotates, the powder material M supplied through the powder supply port 12 of the powder hopper 10 is screwed. While moving from one side of the metering chamber 21 to the other side along the spiral wing of the shaft 22, it may be filled into the metering chamber 21.

At this time, the screw shaft 22 inside the metering chamber 21 can be rotated by a drive motor 25 installed on one side of the support 23 and applying a driving force so that the screw shaft 22 can rotate, The drive motor 25 may be controlled by a control unit (not shown). Accordingly, if the supply amount of the powder material M is input and set in the control unit, the control unit determines the number of rotations of the screw shaft 22 according to the set supply amount of the powder material M, and the drive motor 25 By controlling, it is possible to rotate the screw shaft 22 by the number of rotations.

As such, the powder supply control unit 20 has a structure such as a screw conveyor, and accommodates the powder material M in the measuring chamber 21 in a set quantity according to the number of rotations of the screw shaft 22. I can.

Subsequently, as shown in FIG. 5, when the drive cylinder 24 is driven and its length is elongated, the measuring chamber 21 rotates about 90 degrees, and the powder material M, which is measured and accommodated in a fixed amount, is recoiled. It can be transmitted to the tab 30. At this time, when the measuring chamber 21 is rotated, the powder material M accommodated therein can be easily poured in the rotation direction of the measuring chamber 21, so that the recoater unit ( It can be formed to be inclined in the direction of 30).

In addition, as shown in Figs. 2 and 3, the recoater unit 30 is installed to be reciprocally movable on a pair of rails R installed on the upper surface of the work table T of the 3D printer 1000, While moving in one direction, the powder material (M) received from the powder supply control unit 20 is applied to the upper surface of the work table (T), and applied to the upper surface of the work table (T) while moving in the other direction opposite to the one direction. The powder material (M) can be pressed to a uniform height.

For example, as shown in FIGS. 6 and 7, the recoater unit 30 is formed to be elongated to a length corresponding to the length of the measuring chamber 21, and the powder material (M) received from the measuring chamber 21 A supply chamber 31 in which an upper open inner space is formed to accommodate ), and a coating slit 31a for applying the powder material M to the lower surface is formed, and the inside of the supply chamber 31 It is rotatably installed at a position corresponding to the application slit 31a in the space, and the feeding roller 32 and the outside of the supply chamber 31 apply the powder material M through the application slit 31a by rotation. It is rotatably installed on one side, it may include a recoating roller 34 for pressing the powder material (M) applied by rotation to a uniform height. In addition, the recoater unit 30 is rotatably installed in the inner space of the supply chamber 31, and a stirring roller 33 for stirring so as not to agglomerate the powder material M accommodated in the supply chamber 31 by rotation. It may contain more.

More specifically, as shown in FIG. 8, the feeding roller 32 has a plurality of feeding grooves 32a formed along the outer circumferential surface, so that the feeding roller 32 is fed while rotating inside the supply chamber 31. The powder material M accommodated in the groove 32a may be applied to the outside of the supply chamber 31 through the application slit 31a.

Due to the feeding roller 32, the powder material M inside the supply chamber 31 is not applied at a time through the application slit 31a, but can be induced to be sequentially applied by a predetermined amount. As shown in FIG. 8, the shape of the feeding groove 32a of the feeding roller 32 may be formed to be elongated along the longitudinal direction of the feeding roller 32, but is not limited thereto. It can be formed in a wide variety of shapes so that M) can be applied sequentially in a predetermined amount.

In addition, as shown in FIG. 9, the stirring roller 33 has a plurality of protrusions 33a formed to protrude in a bolt shape on the outer circumferential surface, so that the protrusion 33a when rotated inside the supply chamber 31 As a result, the powder material M accommodated in the supply chamber 31 may be stirred so as not to agglomerate. The shape of the protrusion 33a is not necessarily limited to a bolt shape, and may be formed in a wide variety of shapes capable of effectively stirring the powder material M, such as a spiral wing shape.

Therefore, as shown in Figs. 10 and 11, after measuring the powder material (M) quantitatively through the powder supply control unit 20, and rotate the measuring chamber 21 in the direction of the recoater unit 30, The powder material M measured in a quantity may be delivered to the supply chamber 31 of the recoater unit 30.

At this time, the powder material M transferred to and received in the supply chamber 31 of the recoater unit 30 may be continuously stirred so as not to clump together by the stirring roller 33 rotating in the supply chamber 31, and feeding When the roller 32 rotates, the powder material M may be sequentially applied by a predetermined amount through the application slit 31a.

Hereinafter, using the powder quantitative coating device 100 described above, the process of applying the powder material M in a quantitative amount on the molding stage 310 of the molding box 300 and pressing it to a predetermined height. The 3D printing process of the three-dimensional sculpture (A) will be described in detail.

12 to 14 are cross-sectional views schematically showing a process in which the powder quantitative coating apparatus 100 applies and presses the powder material M, and the three-dimensional sculpture A is formed.

First, referring to FIG. 12, while the powder quantitative coating device 100 moves in one direction on the work table T of the 3D printer 1000, the powder material M measured in a quantity is transferred to the modeling box 300. It can be applied on the molding stage 310. In this case, the surface of the powder material M applied on the molding stage 310 may be formed somewhat irregularly.

Subsequently, as shown in FIG. 13, while the powder quantitative coating device 100 returns in the opposite direction to the one direction, the powder material M applied on the molding stage 310 using the recoating roller 34 By pressing the powder to a uniform height, it is possible to increase the density of the powder material M while forming a very uniform surface of the powder material M applied on the molding stage 310.

Subsequently, as shown in FIG. 14, while the printing head PH of the printing device 400 is moved, the adhesive material B is sprayed to form an adhesive layer having a shape corresponding to the cross-sectional layer of the three-dimensional sculpture A. have.

Thereafter, the molding stage 310 descends a predetermined distance by the elevating device 500 to form the next adhesive layer and repeats the above-described steps, thereby forming a three-dimensional sculpture (A) while stacking and forming a plurality of adhesive layers. I can.

Therefore, according to the powder quantitative coating apparatus 100 and the 3D printer 1000 including the same according to an embodiment of the present invention, the powder material ( M) may be applied, and the powder material M applied on the molding stage 310 may be pressed to a uniform height. Accordingly, the amount of powder material M consumed in the 3D printing process can be reduced by uniformly spreading the powder material M in a high density on the molding stage 310, and the three-dimensional sculpture to be shaped It can have the effect of increasing the quality of 3D printing by increasing the precision and strength of (A).

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and those of ordinary skill in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

According to an embodiment of the present invention made as described above, a quantitatively weighed powder material is applied on the molding stage of the modeling box, and the applied powder material is pressed to a uniform height to achieve a high density uniformly on the molding stage. By making it spread so that it is possible to increase the precision and strength of the three-dimensional sculpture to be shaped. Accordingly, it is possible to have an effect of improving the quality and yield of a three-dimensional sculpture formed by a 3D printer.

Claims

A powder hopper in which a powder material for a 3D printer is stored therein;

Powder which is installed to be connected to the lower part of the powder hopper to supply the powder material stored in the powder hopper, and to control the amount of the powder material supplied from the powder hopper by adjusting the amount of rotation of the screw shaft rotating inside Supply regulator; And

It is installed to be reciprocally movable on a pair of rails installed on the upper surface of the work table of the 3D printer, and while moving in one direction, the powder material received from the powder supply control unit is applied to the upper surface of the work table, and the direction opposite to the one direction A recoater unit for pressing the powdered material applied on the upper surface of the work table to a uniform height while moving in the inter-direction;

Containing, powder quantitative coating device of the three-dimensional printer.
The method of claim 1,

The powder hopper,

A hopper body formed in an inverted pyramid shape with an open upper side; And

A powder supply port formed on a lower surface of the hopper body;

Containing, powder quantitative coating device of the three-dimensional printer.
The method of claim 2,

The powder supply control unit,

A measuring chamber formed to extend long in the width direction of the work table, one side is installed at a position corresponding to the position of the powder supply port, and an upper open inner space for receiving the powder material supplied from the powder hopper is formed ;

The screw shaft rotatably installed in the inner space of the measuring chamber and having a spiral wing portion formed on the outer diameter surface;

Supports rotatably supporting the measuring chamber on both sides of the measuring chamber; And

A driving cylinder installed at the rear side of the measuring chamber to be connected to an upper rear surface of the measuring chamber and rotating the measuring chamber in the direction of the recoater installed in front of the measuring chamber by a linear driving force having a variable length;

Containing, powder quantitative coating device of the three-dimensional printer.
The method of claim 3,

The measuring chamber,

Powder quantitative coating apparatus of a three-dimensional printer, which is formed to be inclined toward the recorder unit as the front surface goes upward.
The method of claim 3,

The powder supply control unit,

A driving motor installed on one side of the support and applying a driving force to rotate the screw shaft; And

A controller that is electrically connected to the drive motor and controls the drive motor according to the set supply amount of the powder material to control the number of rotations of the screw shaft;

Further comprising a powder quantitative coating device of the three-dimensional printer.
The method of claim 3,

The recorder unit,

It is formed to be elongated to a length corresponding to the length of the measuring chamber to form an upper open inner space for receiving the powder material received from the measuring chamber, and the powder material can be applied downward on the lower surface. A supply chamber in which an application slit is formed; And

A feeding roller that is rotatably installed in a position corresponding to the coating slit in the inner space of the supply chamber to apply the powder material through the coating slit by rotation;

Containing, powder quantitative coating device of the three-dimensional printer.
The method of claim 6,

The feeding roller,

Powder quantitative coating apparatus of a 3D printer, wherein a plurality of feeding grooves are formed along the outer circumferential surface.
The method of claim 6,

The recorder unit,

A stirring roller that is rotatably installed in the inner space of the supply chamber and stirs the powdered material accommodated in the supply chamber by rotation;

Further comprising a powder quantitative coating device of the three-dimensional printer.
The method of claim 8,

The stirring roller,

Powder quantitative coating device of a three-dimensional printer, in which a plurality of protrusions protruding in a bolt shape are formed on the outer circumferential surface.
The method of claim 6,

The recorder unit,

A recoating roller that is rotatably installed on one side of the outside of the supply chamber and presses the powder material applied by rotation to a uniform height;

Further comprising a powder quantitative coating device of the three-dimensional printer.
It is formed in a box shape with an open top so that the powder material is accommodated to form an inner space in which a three-dimensional sculpture can be formed, and it is provided to be elevating and descending inside the three-dimensional sculpture in a plurality of layers. A modeling box including a molding stage that is laminated and molded;

A body in which a modeling box receiving part in which the modeling box is accommodated is formed;

The method of claim 1, wherein the powder material is applied quantitatively so that a powder layer having a predetermined thickness can be formed on the molding stage of the modeling box accommodated in the modeling box receiving part and installed on one side of the upper part of the body. Powder quantitative coating device according to any one of claims 10;

A printing device installed on the other side of the upper portion of the body and spraying an adhesive material onto the powder layer applied on the molding stage in an inkjet manner; And

An elevating device installed below the modeling box receiving part to raise and lower the modeling stage of the modeling box;

Containing, 3D printer.