3D printing device

Abstract

The invention discloses a 3D printing device. The 3D printing device comprises a workbench used for providing a supporting foundation of a modeling object to be modeled; the first nozzle and the second nozzle are arranged on the workbench, the first nozzle is used for spraying out a pasty or pasty first material for forming the contour of the molded object, and the second nozzle is used for spraying out a liquid second material for filling a filling space defined by the contour of the molded object formed by the first material; an extrusion device connected to the first nozzle and configured to extrude the first material toward the first nozzle so as to eject a pasty or pasty first material in which the ceramic particles and the matrix in which the ceramic particles are dispersed are mixed; a heating funnel connected to the second nozzle and used for melting the metal block with the metal block as input so that a second material of a liquid metal flow formed by melting the metal block is ejected through the second nozzle; and a heating chamber accommodating the table and providing a slow cooling space for the first material and the second material accumulated on the table from the first nozzle and the second nozzle. According to the present invention, provided is a 3D printing apparatus which has a simplified structure for manufacturing a molded object, can shorten the manufacturing time of the molded object, and can form a molded object having a smooth surface, an attractive appearance, and reduced internal defects such as voids and thermal stress.

Description

Technical Field

[0001] The invention relates to a 3D printing device. Background Art

[0002] A 3D printing device is a device for molding an object with a specific shape, for example, taking slice cross-sectional data of the object to be molded as input, and manufacturing the object by stacking various layers of the object. For example, in such a 3D printing device, the three-dimensional shape of the object to be molded can be generated as digital data through computer modeling, and after two-dimensional plane differentiation is performed on it, the object with a three-dimensional shape can be manufactured by continuously stacking the differentiated materials. Summary of the invention

[0003] Technical issues

[0004] One embodiment of the present invention includes a 3D printing device that can shorten the time it takes to create a modeled object.

[0005] One embodiment of the present invention includes a 3D printing device having a structure for making a modeled object.

[0006] One embodiment of the present invention includes a 3D printing device that can form a modeled object with a smooth surface and beautiful appearance, and at the same time form a modeled object with reduced internal defects such as voids and thermal stress.

[0007] Technical Solution

[0008] In order to solve the above and other problems, the 3D printing device of the present invention includes:

[0009] A workbench, which is used to provide a support base for the object to be shaped;

[0010] A first nozzle and a second nozzle are arranged on the workbench, the first nozzle is used to spray out a first material in a paste or slurry state to form the outline of the object, and the second nozzle is used to spray out a second material in a liquid state to fill a filling space surrounded by the outline of the object formed by the first material;

[0011] an extrusion device connected to the first nozzle and used for extruding the first material toward the first nozzle so as to eject the first material in a paste or slurry state formed by mixing ceramic particles and a matrix in which the ceramic particles are dispersed;

[0012] a heating funnel connected to the second nozzle and used to take a metal block as an input and melt the metal block so as to eject the second material in the form of a liquid metal flow formed by melting the metal block through the second nozzle; and

[0013] A heating chamber accommodates the workbench and provides a slow cooling space for the first material and the second material accumulated on the workbench from the first nozzle and the second nozzle.

[0014] Beneficial Effects

[0015] According to the present invention, a 3D printing device is provided, which has a structure for making a modeling object, can shorten the production time of the modeling object, and can form a modeling object with a smooth surface and beautiful appearance, and reduced internal defects such as voids and thermal stress. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 4 is an overall stereoscopic view of a 3D printing device according to an embodiment of the present invention.

[0017] Figure 2 Is used to describe Figure 1 The figure of the molding of the object to be molded by the 3D printing device shown in FIG. Figure 1 A partial structural plan.

[0018] Figure 3 Is used to describe Figure 1 The 3D printing device shown in the figure is used to shape the object to be shaped, showing the Figure 2 Cross-sectional view along line III-III'.

[0019] Figure 4 Is used to describe Figure 1 The figure of the molding of the object to be molded by the 3D printing device shown is a figure used to describe the contour of the object and the molding of the object, wherein the contour of the object is formed from the first ejection position and the second ejection position on the workbench that ejects different first materials and second materials, and the object fills the filling space surrounded by the contour of the object.

[0020] Figure 5 Is used to describe Figure 1 The extrusion apparatus shown in FIG. Figure 1 Schematic diagram of the structure of the extrusion device.

[0021] Figure 6 and Figure 7 It is a diagram for describing the contour of a modeling object and the molding of the modeling object. The contour of the modeling object is formed from a first ejection position and a second ejection position on a workbench that ejects a first material and a second material. The modeling object fills a filling space surrounded by the contour of the modeling object. Diagrams are respectively shown for describing a driving mode in which the ejection of the first material and the second material is performed in a chronological order and a driving mode in which the ejection of the first material and the second material is performed simultaneously.

[0022] Figure 8 yes Figure 1A perspective view of a portion of a 3D printing device is shown.

[0023] Fig. 9 It is used to describe the embedded Figure 8 An exploded perspective view of the assembly between the heating funnel, the ejection unit and the first heat source within the embedded block is shown.

[0024] Fig.10 It is an exploded perspective view used to describe the airtight assembly between the insert block and the heating chamber.

[0025] Fig.11 is used to describe the formation of Fig.10 An exploded perspective view of the ejection holes on the insert block is shown.

[0026] Fig.12 This is a diagram for describing a sealing cover provided on a heating funnel and a structure for controlling a flow rate (volume passing through a cross-sectional area per unit time) or a discharge speed of a second material in the heating funnel according to the internal pressure of a gas filled in the sealing cover.

[0027] Fig.13 (a) is a diagram exemplarily showing a temperature curve of a first temperature T1 in the heating hopper 10 and a temperature curve of a second temperature T2 of the ejection unit 20 that are followed as target temperatures during a takt time for producing one molded object.

[0028] Fig.13 (b) is a diagram exemplarily showing a temperature curve of the third temperature T3 in the heating chamber 50 followed as a target temperature during the takt-time for making a molded object, and exemplarily showing a slow curve of the third temperature T3 for slow cooling of the molded object.

[0029] Fig.14 (a) and Fig.14 (b) is a diagram for summarizing changes in the transport amount of the stage S required to move to the same target position according to different intervals g between the first nozzle 20a and the second nozzle 10a.

[0030] Fig.15 and Fig.16 Is used to describe Figure 1 Different views of the power connection between the workbench S providing the support base of the sculpted object and the actuator A, the bellows cover ZC for sealing the opening 50"' of the heating chamber 50 independently of the drive of the actuator A, and the connecting rod structure L connected to the bellows cover ZC. DETAILED DESCRIPTION

[0031] Best Mode

[0032] The 3D printing device of the present invention comprises:

[0033] A workbench, which is used to provide a support base for the object to be shaped;

[0034] A first nozzle and a second nozzle are arranged on the workbench, the first nozzle is used to spray out a first material in a paste or slurry state to form the outline of the object, and the second nozzle is used to spray out a second material in a liquid state to fill a filling space surrounded by the outline of the object formed by the first material;

[0035] an extrusion device connected to the first nozzle and used for extruding the first material toward the first nozzle so as to eject the first material in a paste or slurry state formed by mixing ceramic particles and a matrix in which the ceramic particles are dispersed;

[0036] a heating funnel connected to the second nozzle and used to take a metal block as an input and melt the metal block so as to eject the second material in the form of a liquid metal flow formed by melting the metal block through the second nozzle; and

[0037] A heating chamber accommodates the workbench and provides a slow cooling space for the first material and the second material accumulated on the workbench from the first nozzle and the second nozzle.

[0038] For example, the inner diameter of the second nozzle may be smaller than a diameter corresponding to the longest dimension of the metal block fed from the feed port at the upper end of the heating funnel connected to the lower end of the second nozzle.

[0039] For example, the inner diameter of the disk-shaped metal block can be formed to be 50 mm in diameter.

[0040] The inner diameter of the second nozzle may be formed to be 0.1 mm to 4 mm, for example, may be formed to be 1 mm to 2 mm.

[0041] For example, the heating funnel may be formed in a Y shape so that the inner diameter of the feed port at the upper end where the metal block is fed to the inner diameter of the second nozzle at the lower end where the second material of the metal flow is ejected gradually decreases.

[0042] For example, a first heat source is wound along the outer peripheral surface of the heating funnel, and the first heat source is used to melt the metal block put into the heating funnel.

[0043] For example, the first heat source may be disposed between the heating funnel and the ejection unit, a second nozzle may be formed at a lower end of the heating funnel opposite to the workbench, and a first nozzle may be formed at a lower end of the ejection unit opposite to the workbench.

[0044] For example, the 3D printing device may further include an embedding block, and the embedding block is used to embed the first nozzle and the second nozzle together.

[0045] For example, the embedding block may fix the positions of the first nozzle and the second nozzle by embedding them so that the interval between the first nozzle and the second nozzle is maintained between 3 mm and 50 mm. For example, the embedding block may maintain the interval between the first nozzle and the second nozzle at about 25 mm.

[0046] For example, the embedded block is formed within a height range from the lower end of the heating funnel and the ejection unit, where the first nozzle and the second nozzle are formed respectively, to the mating end of the feed port at the upper end of the heating funnel and the upper end of the ejection unit,

[0047] A connecting pipe body may be inserted into the mating end portion at the upper end of the ejection unit, and the connecting pipe body is used to mediate the transportation of the first material between the ejection unit and the extrusion device.

[0048] For example, the embedded block can surround the first heat source wrapped around the outer circumference of the heating funnel while surrounding the ejection unit, the ejection unit is separated from the first heat source wrapped around the outer circumference of the heating funnel and extends parallel to the outer circumference of the heating funnel.

[0049] For example, the ejection unit may include a second nozzle, which extends from the bend of the ejection unit toward the workbench and parallel to the first nozzle, so as to extend in parallel with the outer peripheral surface of the heating funnel while following the height direction and radial oblique direction of the heating funnel, and then extends parallel to the first nozzle extending from the bottleneck forming the minimum inner diameter of the heating funnel toward the workbench.

[0050] For example, the second temperature of the heating funnel and the first temperature of the ejection unit may satisfy the relationship of second temperature>first temperature.

[0051] For example, the temperature deviation between the first temperature and the second temperature may be induced by a thermal resistance formed by an insulating material of an embedding block filled between the heating funnel and the ejection unit extending parallel to each other.

[0052] For example, the second temperature of the heating funnel can be set to a sufficiently high temperature equal to or higher than the melting point of the metal block.

[0053] The first temperature of the ejection unit may be set to a sufficiently low temperature to suppress gasification or volatilization of the matrix mixed in the first material.

[0054] For example, the third temperature of the slow cooling space of the heating chamber, the second temperature of the heating funnel, and the first temperature of the ejection unit may satisfy the relationship of second temperature>third temperature>first temperature.

[0055] For example, the third temperature of the slow cooling space of the heating chamber may be set to a temperature high enough to induce gasification or volatilization of the matrix mixed in the first material in the slow cooling space.

[0056] For example, the embedding block and the heating chamber may be connected vertically via a spray hole, and the spray hole is used to allow the first material and the second material to flow from the first nozzle and the second nozzle embedded in the embedding block to the workbench accommodated in the slow cooling space of the heating chamber.

[0057] For example, the embedding block may include:

[0058] An upper block for embedding a spray unit including a first spray unit and a second spray unit at a lower end, respectively, and a heating funnel; and

[0059] The lower block is formed in a plate shape with an area expanded from the upper block and is used to cover the upper part of the slow cooling space.

[0060] For example, the heating chamber may include a plurality of partition walls which are in contact with the lower block through a stepped interface and cover the side surfaces of the slow cooling space.

[0061] For example, adjacent partition walls forming corners of the heating chamber may abut against each other via a stepped interface.

[0062] For example, the heating chamber may further include a bottom wall, the bottom wall providing an assembly position for the plurality of partitions and forming an opening for a connecting rod to pass through, the connecting rod being used to mediate a power connection between the workbench in the slow cooling space and the actuator outside the slow cooling space,

[0063] The 3D printing device may further include a bellows cover superimposed on the bottom wall to cover the opening through a connecting rod structure extending parallel to the connecting rod and extending and retracting according to the lifting and lowering of the actuator.

[0064] For example, the 3D printing device may further include:

[0065] A first heat source, which is wound along the outer peripheral surface of the heating funnel and is used to melt the metal block put into the heating funnel; and

[0066] A second heat source is formed in the heating chamber and is used to control a cooling rate of the first material and the second material accumulated on the worktable from the first nozzle and the second nozzle.

[0067] For example, during the takt time for forming a shape,

[0068] A first startup time from the start of startup to the end of startup of the first heat source and a second startup time from the start of startup to the end of startup of the second heat source may have a magnitude relationship of first startup time<second startup time.

[0069] For example, during the takt time for forming a shape,

[0070] The second heat source can continue to be activated even after the activation of the first heat source ends to control the cooling speed of the object.

[0071] For example, the 3D printing device may not be equipped with a sintering device for solidifying the object to complete the solid object.

[0072] For example, the first nozzle and the second nozzle may be activated together, and the ejection positions of the first material and the second material may be formed simultaneously on the workbench.

[0073] For example, a flow rate of the first material sprayed from the first nozzle toward the worktable may be less than a flow rate of the second material sprayed from the second nozzle toward the worktable.

[0074] For example, the volume of the outline of the object formed by the first material may be smaller than the volume of the object itself formed by the second material.

[0075] For example, the extrusion device may include: a first hopper and a second hopper, which are used to respectively input ceramic particles and a matrix; a conveying pipe, which is connected to the first hopper and the second hopper; and a rotating screw, which is driven to rotate inside the conveying pipe, on the one hand forming a first material by mixing the ceramic particles and the matrix input from the first hopper and the second hopper, and on the other hand forcing the first material to be transported along the direction of the conveying pipe.

[0076] For example, the flow rate of the first material sprayed from the first nozzle to the workbench can be controlled by the rotation speed of the rotating screw driven inside the delivery tube.

[0077] For example, the flow rate of the second material sprayed from the second nozzle to the workbench can be controlled by the pressure of the gas on the liquid surface of the second material of the metal flow filling the inside of the heating funnel, for example, can be controlled by the pressure of the inert gas.

[0078] In one embodiment of the present invention, the 3D printing device may include:

[0079] A workbench, which is used to provide a support base for the object to be shaped;

[0080] A first nozzle and a second nozzle are arranged on the workbench, the first nozzle is used to spray out a first material in a paste or slurry state to form the outline of the object to be shaped, and the second nozzle is used to spray out a second material in a liquid state to fill a filling space surrounded by the first material;

[0081] An extrusion device connected to the first nozzle and extruding a first material in a paste or slurry state toward the first nozzle, wherein the first material includes ceramic particles and a matrix in which the ceramic particles are dispersed;

[0082] a heating funnel connected to the second nozzle and used to take the metal block as input, melt the metal block to supply molten metal, that is, the second material in a liquid state; and

[0083] The heating chamber is used to accommodate the workbench and provide a slow cooling space for the molded object formed by the first material and the second material accumulated on the workbench.

[0084] A 3D printing method according to an embodiment of the present invention may include:

[0085] Extruding a first material in a paste or slurry state from an extrusion device to a first nozzle, wherein the first material comprises ceramic particles and a matrix in which the ceramic particles are dispersed;

[0086] Spraying a first material forming a contour of a modeling object to be modeled through a first nozzle;

[0087] Containing the metal block through a heated funnel;

[0088] melting the metal block and forming a flow of the molten metal block so that a second material of the molten metal is directed toward a second nozzle;

[0089] Spraying the second material through the second nozzle to fill the filling space surrounded by the outline of the modeling object formed by the first material with the second material; and

[0090] The first material and the second material are repeatedly sprayed out layer by layer to form a modeling object on the workbench. DETAILED DESCRIPTION

[0092] Hereinafter, a 3D printing device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

[0093] In one embodiment of the present invention, the 3D printing device can use the same material or two or more materials to form the object to be shaped. In this case, the two or more materials can have the same phase (solid, liquid, solid-liquid mixed state) or different phases.

[0094] In one embodiment of the present invention, the 3D printing device can use multi-phase materials, and the multi-phase materials can refer to at least two different materials (first material and second material) with two different phases. In one embodiment of the present invention, the two different phases can broadly refer to solid, liquid, gaseous, molten, mixed (solid-liquid mixed), etc. At least two materials can be used in different proportions or used separately from each other. In one embodiment of the present invention, the object to be shaped can be stacked layer by layer on the workbench of the 3D printing device.

[0095] Figure 1 4 is an overall stereoscopic view of a 3D printing device according to an embodiment of the present invention.

[0096] Figure 2 Is used to describe Figure 1 The figure of the molding of the object to be molded by the 3D printing device shown in FIG. Figure 1 A partial structural plan.

[0097] Figure 3 Is used to describe Figure 1 The 3D printing device shown in the figure is used to shape the object to be shaped, showing the Figure 2 Cross-sectional view along line III-III'.

[0098] Figure 4 Is used to describe Figure 1 The figure of the molding of the object to be molded by the 3D printing device shown is a figure used to describe the contour of the object and the molding of the object. The contour of the object is formed from the first ejection position P1 and the second ejection position P2 on the workbench S that ejects different first materials M1 and second materials M2, and the object fills the filling space FS surrounded by the contour of the object.

[0099] Figure 5 Is used to describe Figure 1 The extrusion device 80 shown in FIG. Figure 1 A schematic structural diagram of an extrusion device 80.

[0100] Figure 6 and Figure 7 It is a diagram for describing the contour of a modeling object and the molding of the modeling object. The contour of the modeling object is formed from a first ejection position P1 and a second ejection position P2 on a workbench S where a first material M1 and a second material M2 are ejected. The modeling object fills a filling space FS surrounded by the contour of the modeling object. Diagrams are respectively shown for describing a driving mode in which the first material M1 and the second material M2 are ejected in a chronological order and a driving mode in which the first material M1 and the second material M2 are ejected simultaneously.

[0101] Figure 8 yes Figure 1 A perspective view of a portion of a 3D printing device is shown.

[0102] Fig. 9 It is used to describe the embedded Figure 8 An exploded perspective view of the assembly between the heating funnel 10, the ejection unit 20 and the first heat source 15 within the embedded block 40 is shown.

[0103] Fig.10 4 is an exploded perspective view for describing the airtight assembly between the insert block 40 and the heating chamber 50 .

[0104] Fig.11 is used to describe the formation of Fig.10 An exploded perspective view of a spray hole 40" on an insert block 40 is shown.

[0105] Fig.12 It is a diagram for describing a sealing cover 1 provided on a heating funnel 10 and a structure for controlling a flow rate (volume passing through a cross-sectional area per unit time) or a discharge speed of a second material M2 in the heating funnel 10 according to the internal pressure of a gas RG filled in the sealing cover 1 .

[0106] Fig.13 (a) is a diagram exemplarily showing a temperature curve of a first temperature T1 in the heating hopper 10 and a temperature curve of a second temperature T2 of the ejection unit 20 that are followed as target temperatures during a takt time for producing one molded object.

[0107] Fig.13 (b) is a diagram exemplarily showing a temperature curve of the third temperature T3 in the heating chamber 50 followed as a target temperature during the takt-time for making a molded object, and exemplarily showing a slow curve of the third temperature T3 for slow cooling of the molded object.

[0108] Fig.14 (a) and Fig.14 (b) is a diagram for summarizing changes in the transport amount of the stage S required to move to the same target position according to different intervals g between the first nozzle 20a and the second nozzle 10a.

[0109] Fig.15 and Fig.16 Is used to describe Figure 1 Different views of the power connection between the workbench S providing the support base of the sculpted object and the actuator A, the bellows cover ZC for sealing the opening 50"' of the heating chamber 50 independently of the drive of the actuator A, and the connecting rod structure L connected to the bellows cover ZC.

[0110] Referring to the accompanying drawings, a 3D printing device according to an embodiment of the present invention may include: a workbench S, which is used to provide a support base for a modeling object to be modeled; a first nozzle 20a and a second nozzle 10a arranged on the workbench S, wherein the first nozzle 20a is used to spray out a first material M1 in a paste or slurry state to form the outline of the modeling object, and the second nozzle 10a is used to spray out a liquid second material M2 to fill a filling space FS surrounded by the modeling object outline formed by the first material M1; an extruder 80, which is connected to the first nozzle 20a and is used to eject a liquid second material M2 into the first nozzle 20a. 0a, extruding a first material M1 so as to eject the first material M1 in a paste or slurry form which is a mixture of ceramic particles and a matrix in which the ceramic particles are dispersed; a heating funnel 10, which is connected to a second nozzle 10a and is used to take a metal block as an input, melt the metal block, so as to eject the second material M2 in a liquid metal flow formed by the melted metal block through the second nozzle 10a; and a heating chamber 50, which accommodates a workbench S and provides a slow cooling space 50' for the first material M1 and the second material M2 accumulated on the workbench S from the first nozzle 20a and the second nozzle 10a.

[0111] The 3D printing apparatus according to an embodiment of the present invention can form a three-dimensional object by accumulating the first material M1 and the second material M2 supplied from the first nozzle 20 a and the second nozzle 10 a according to slice cross-sectional data of the three-dimensional object to be formed.

[0112] In one embodiment of the present invention, the first material M1 used to form the contour of the object to be shaped may be formed by mixing ceramic particles with a matrix in which the ceramic particles are dispersed in a paste or slurry. More specifically, the first material M1 may be formed by mixing ceramic particles with a matrix for providing fluidity to the ceramic particles in a paste or slurry. In one embodiment of the present invention, the matrix is ​​a base material that is mixed with a plurality of ceramic particles and accommodates the plurality of ceramic particles in a dispersed form to form a paste or slurry of the first material M1 in which a plurality of ceramic particles are dispersed. For example, it may have a material phase with fluidity such as a liquid or gel state, and may include water (H2O) for providing fluidity to the plurality of ceramic particles. In one embodiment of the present invention, the matrix may include water (H2O) as a carrier for imparting fluidity to the ceramic particles. In addition, for example, a binder for controlling the viscosity of the first material M1 may not be included. In a specific embodiment of the present invention, the first material M1 may include a plurality of ceramic particles and water (H2O) as a matrix in which a plurality of ceramic particles are dispersed. On the other hand, the second material M2 used to form the object itself within the contour of the object can be formed of liquid metal H2O, more specifically, can be formed of a liquid metal flow.

[0113] In one embodiment of the present invention, the first material M1 and the second material M2 can be prepared by different pretreatment processes using different first raw materials and second raw materials, respectively. For example, since the paste-like or slurry-like first material M1 and the liquid-like second material M2 have different material phases and different fluidities, the first material M1 and the second material M2 can be supplied to the workbench S, respectively, through different pretreatment processes.

[0114] For the first material M1, the first material M1 may be formed by a paste or slurry composite material formed by mixing solid ceramic particles with a liquid (or gel) carrier and / or adhesive, for example, the ceramic particles may have a particle size of micrometers (μm). Since the first material M1 is in a paste or slurry with ceramic particles dispersed therein, its fluidity may be lower than that of the second material M2 formed as a liquid metal or metal flow, and in order to form a uniform mixture (or uniform concentration dispersion) between ceramic particles (solid) having different material phases and the matrix (liquid or gel) contained by the ceramic particles, the first material M1 may be forcibly conveyed through the first nozzle 20a or the connecting tube body 70 connected to the first nozzle 20a by extrusion.

[0115] For example, the extrusion device 80 for extruding the first material M1 may include: a first hopper 81, which is used to input ceramic particles that form the solid component of the first material M1; and a second hopper 82, which is used to input a matrix containing the ceramic particles to form a paste or slurry. The ceramic particles and the matrix input from the first hopper 81 and the second hopper 82 are input together into the conveying pipe 83 of the extrusion device 80, and can be conveyed along the supply direction toward the workbench S while being mixed with each other through the rotating screw 85 formed inside the conveying pipe 83. For example, the conveying of the first material M1 can be mediated between the nozzle 80a of the extrusion device 80 and the first nozzle 20a formed on the workbench S or the ejection unit 20 including the first nozzle 20a at the lower end through the connecting tube body 70, and can be ejected onto the workbench S through the first nozzle 20a at the lower end of the ejection unit 20 along the ejection unit 20 embedded in the later-described embedded block 40. For example, in one embodiment of the present invention, the upstream end of the connecting tube body 70 can be connected to the ejection port 80a of the extrusion device 80, and the downstream end of the connecting tube body 70 can be connected to the ejection unit 20 including the first nozzle 20a at the lower end.

[0116] Although not shown in the drawings, throughout this specification, the extrusion device 80 is not limited to the structure based on the rotating screw 85 as described above, and can be broadly interpreted, for example, it can also broadly refer to a piston-based extrusion device, in which the pretreated ceramic paste contained in the piston container is pressurized toward the ejection unit 20 according to the piston drive.

[0117] For the second material M2, the second material M2 can be formed into a liquid metal or metal flow formed by a heating funnel 10 that takes a solid metal block as input and heats the input metal block to a melting point or a higher temperature. The molten metal or metal flow in the internal space of the heating funnel 10 can be sprayed onto the workbench S through a second nozzle 10a formed at the lower end of the heating funnel 10.

[0118] In other words, in one embodiment of the present invention, the raw material of the second material M2 (second raw material), that is, the metal block, can be put into the heating funnel 10 including the second nozzle 10a at the lower end for ejecting the second material M2, and the heating funnel 10 is heated to the melting point of the metal block or a higher temperature, thereby forming a liquid metal flow for forming the second material M2. For example, in one embodiment of the present invention, the low-melting-point metal block as the raw material of the second material M2 (second raw material) can be formed into a disc-shaped with a relatively low height and a slender size, wherein the longest dimension of the low-melting-point metal block can correspond to the diameter of the disc, and the diameter of the low-melting-point metal block can be about 50 mm. In one embodiment of the present invention, the heating funnel 10 that uses the low-melting-point metal block as an input and ejects the metal flow can be formed into a roughly Y-shaped funnel shape, and the inner diameter of the second nozzle 10a at the lower end for ejecting the metal flow can be smaller than the inner diameter of the feed port at the upper end for injecting the low-melting-point metal block. For example, the inner diameter of the feed port at the upper end where the low-melting-point metal block is fed may be larger than the longest dimension of the low-melting-point metal block, whereas the inner diameter of the second nozzle 10a at the lower end where the metal flow formed by the low-melting-point metal block melted in the heating funnel 10 is ejected may be smaller than the longest dimension of the low-melting-point metal block. More specifically, the longest dimension of the low-melting-point metal block may correspond to the diameter of the disc in the disc shape of the low-melting-point metal block. When the diameter of the disc is about 50 mm, in one embodiment of the present invention, the inner diameter of the second nozzle 10a may be smaller than the diameter of the solid disc of 50 mm, and may be about 0.1 mm to 4 mm, for example, and may be formed to be about 1 mm to 2 mm.

[0119] In the present specification, the up-down direction Z1 or the height direction Z1 may correspond to the direction in which the first material M1 and the second material M2 are sprayed from the first nozzle 20a and the second nozzle 10a onto the workbench S, and may refer to the direction in which the first nozzle 20a and the second nozzle 10a that respectively spray the first material M2 and the second material M2 are spaced apart from the workbench S. For example, the lower end and the upper end of the heating funnel 10 may refer to the proximal end relatively close to the workbench S and the distal end relatively far away from the workbench S of the two ends of the heating funnel 10 along the height direction Z1. Similarly, the lower end and the upper end of the ejection unit 20 may refer to the proximal end relatively close to the workbench S and the distal end relatively far away from the workbench S of the two ends of the ejection unit 20.

[0120] In one embodiment of the present invention, the heating funnel 10 may correspond to a configuration for ejecting the first material M1 onto the workbench S through a first nozzle 20a formed at the lower end, and the ejection unit 20 may correspond to a configuration for ejecting the second material M2 onto the workbench S through a second nozzle 10a formed at the lower end. As described below, the heating funnel 10 and the ejection unit 20 may be embedded together in an embedding block 40, and the embedding block 40 fixes its position by embedding the heating funnel 10 and the ejection unit 20 together, so that a gap g between the first nozzle 20a forming the lower end of the heating funnel 10 and the second nozzle 10a forming the lower end of the ejection unit 20 may be defined. In one embodiment of the present invention, the embedded block 40 may surround the first heat source 15 wound around the outer circumference of the heating funnel 10, and isolate the internal space of the heating funnel 10 from the surrounding environment, so as to maintain the temperature of the internal space of the heating funnel 10 controlled by the first heat source 15 at a second temperature T2 of the melting point of the metal block or higher, and maintain the temperature of the ejection unit 20 arranged on the opposite side of the heating funnel 10 across the first heat source 15 at a first temperature T1 higher than the ambient temperature or room temperature but lower than the melting point of the metal block. In one embodiment of the present invention, the embedded block 40 may be formed of an insulating material, interposed between the heating funnel 10 and the ejection unit 20 for ejecting the first material M1 and the second material M2, respectively, to form a thermal resistance therebetween to induce a temperature difference, for example, the second temperature T2 of the internal space of the heating funnel 10 may be formed to be the melting point of the metal block or higher, and the first temperature T1 of the ejection unit 20 may be maintained at a temperature lower than the melting point of the metal block but higher than the ambient temperature or room temperature.

[0121] In one embodiment of the present invention, the heating funnel 10 may be formed into a substantially Y-shaped funnel shape that gradually decreases from the inner diameter of the feed port at the upper end to the inner diameter of the second nozzle 10a at the lower end. At this time, the ejection unit 20 may extend along an inclined oblique direction to extend parallel to the heating funnel 10. The heating funnel 10 and the ejection unit 20 extending parallel to each other may maintain a constant interval from the second nozzle 10a and the first nozzle 20a at the upper end to the lower end along the height direction Z1. For example, in one embodiment of the present invention, the heating funnel 10 may extend in a funnel shape with an inner diameter gradually decreasing along the height direction Z1 to the radial directions Z2 and Z3, and then form the second nozzle 10a at the lower end that extends straightly along the height direction Z1 toward the workbench S. The ejection unit 20 extending parallel to the heating funnel 10 may extend along an oblique direction to simultaneously follow the height direction Z1 and the radial directions Z2 and Z3, and then form the first nozzle 20a that extends straightly along the height direction Z1 toward the workbench S. In one embodiment of the present invention, the heating funnel 10 and the ejection unit 20 may form deformation points at the positions of the second nozzle 10a and the first nozzle 20a, respectively, and simultaneously form a bottleneck of the minimum inner diameter of the heating funnel 10 or form a bend of the ejection unit 20. In one embodiment of the present invention, the bottleneck of the heating funnel and the bend of the ejection unit may be formed at the same level in the height direction.

[0122] In one embodiment of the present invention, the heating funnel 10 and the ejection unit 20 can extend in parallel at the same level and maintain the same interval along the height direction Z1, and the heating funnel 10 and the ejection unit 20 can maintain the same interval as the interval g between the second nozzle 10a and the first nozzle 20a forming their respective lower ends, and the second nozzle 10a and the first nozzle 20a extending from the upper end to the lower end.

[0123] In one embodiment of the present invention, the temperatures of the respective heating funnels 10 and the ejection units 20 can be maintained at different first temperatures T1 and second temperatures T2 by means of a first heat source 15 interposed between the heating funnels 10 and the ejection units 20 and an embedded block 40 filling the gap between the heating funnels 10 and the ejection units 20. For example, a thermal resistance can be formed by means of the insulating material of the embedded block 40 filling the gap between the heating funnels 10 and the ejection units 20, thereby maintaining the heating funnel 10 and the ejection unit 20 at different second temperatures T2 and first temperatures T1, respectively.

[0124] The first temperature T1 may correspond to a temperature lower than the melting point of the metal block but higher than the ambient temperature or room temperature, and the second temperature T2 may correspond to the melting point of the metal block or a higher temperature. In one embodiment of the present invention, the first temperature T1 of the ejection unit 20 may correspond to a sufficiently low temperature to suppress the gasification or volatilization of the matrix in which the ceramic particles are dispersed in the first material M1 ejected from the first nozzle 20a forming the lower end of the ejection unit 20, while maintaining the paste or slurry state of the first material M1, and may correspond to a sufficiently high temperature to suppress the rapid cooling of the liquid second material M2 that abuts against the first material M1 forming the contour of the object on the workbench S and forms the object itself and the resulting quenching heat treatment effect, in other words, to maintain the slow cooling of the second material M2 through the contact between the first material M1 and the second material M2, thereby inducing the annealing heat treatment effect on the second material M2 abutting against the first material M1 forming the contour of the object. On the other hand, the second temperature T2 of the heating funnel 10 or the second temperature T2 of the internal space of the heating funnel 10 may correspond to the melting point of the metal block or a higher temperature. In order to melt the metal block put into the internal space of the heating funnel 10 and eject the second material M2 in liquid form through the second nozzle 10a forming the lower end of the heating funnel 10, the second temperature T2 of the internal space of the heating funnel 10 may correspond to the melting point of the metal block or a higher temperature. For example, in one embodiment of the present invention, the first heat source 15 may be wound along the outer circumference of the heating funnel 10 and maintain the temperature of the internal space of the heating funnel 10 at the second temperature T2 of the melting point of the metal block or a higher temperature, the internal space of the heating funnel 10 may be insulated from the surrounding environment by the embedded block 40 surrounding the first heat source 15 wound on the outer circumference of the heating funnel 10, and the insulating material of the embedded block 40 filled in the gap between the outer circumference of the heating funnel 10 wound with the first heat source 15 and the ejection unit 20 may form a thermal resistance that can induce a temperature difference between the second temperature T2 of the internal space of the heating funnel 10 and the first temperature T1 of the ejection unit 20.For example, in one embodiment of the present invention, the first temperature T1 may correspond to a temperature lower than the melting point of the metal block but higher than the ambient temperature or room temperature, and the second temperature T2 may correspond to the melting point of the metal block or a higher temperature, accordingly, the relationship of the first temperature T1 of the ejection unit 20 < the second temperature T2 of the heating funnel 10 (or the second temperature T2 of the internal space of the heating funnel 10) may be satisfied, and the first heat source 15 involving the first temperature T1 of the ejection unit 20 and the second temperature T2 of the heating funnel 10 is interposed between the ejection unit 20 and the heating funnel 10 extending parallel to each other, and in order to form a relatively high second temperature T2, it may be arranged closer to the heating funnel 10 side, for example, the first heat source 15 may be wrapped around the outer peripheral surface of the heating funnel 10, and the ejection unit 20 may be arranged by interposing the insulating material of the embedded block 40 between it and the first heat source 15 wrapped around the outer peripheral surface of the heating funnel 10.

[0125] Throughout this specification, the embedding block 40 embeds the heating funnel 10 and the ejection unit 20 together, which does not mean that the embedding block 40 completely embeds the entirety of the heating funnel 10 and the ejection unit 20, but can broadly refer to completely embedding the first nozzle 20a and the second nozzle 10a forming the lower ends of the heating funnel 10 and the ejection unit 20, while the feed port forming the upper end of the heating funnel 10 can be confirmed in appearance, and the feed port forming the upper end of the heating funnel 10 is exposed, and the upper end of the ejection unit 20 inserted into the connecting pipe body 70 connected to the extruder 80 is exposed. For example, regarding the position of the heating funnel 10 embedded from the embedding block 40, the embedding block 40 can embed most of the heating funnel 10 wound with the first heat source 15, but can expose the upper part of the heating funnel 10 from the feed port forming the upper end of the heating funnel 10 to the winding start level where the first heat source 15 starts to be wound. In one embodiment of the present invention, in order to block the heat loss from the first heat source 15 wound on the outer peripheral surface of the heating funnel 10, the embedded block 40 can provide thermal insulation from the surrounding environment. To this end, in one embodiment of the present invention, the embedded block 40 can be embedded in the heating funnel 10 at least from the winding starting point to the winding end point of the first heat source 15, for example, the portion from the feed port formed at the upper end of the heating funnel 10 to before the winding starting point of the first heat source 15 can be exposed.

[0126] In one embodiment of the present invention, the embedding block 40 may embed most of the heating funnel 10 and the ejection unit 20, but expose the feed port forming the upper end of the heating funnel 10 and the mating end 20b forming the upper end of the ejection unit 20, and the upper part of the heating funnel 10 and the ejection unit 20 may be exposed to respectively have a certain space including the upper end of the heating funnel 10 for inserting the metal block and the upper end of the ejection unit 20 for connecting the connecting pipe body 70. On the other hand, in one embodiment of the present invention, in addition to the feed port forming the upper end of the heating funnel 10 and the mating end 20b forming the upper end of the ejection unit 20, the electrical contact 15a of the first heat source 15 surrounding the outer peripheral surface of the heating funnel 10 may be exposed at the upper part of the embedding block 40, and the electrical contact 15a of the first heat source 15 may protrude to the highest level to prevent electrical interference with other surrounding configurations, for example, it may protrude to a level higher than the feed port of the heating funnel 10 and the mating end 20b of the ejection unit 20 in the height direction Z1.

[0127] In one embodiment of the present invention, the embedding block 40 may be embedded in the heating funnel 10 and the ejection unit 20 together with the first heat source 15, and the embedding block 40 embedded in the heating funnel 10 and the ejection unit 20 together may be connected to a heating chamber 50, the heating chamber 50 accommodating a workbench S for accumulating the first material M1 and the second material M2 from the first nozzle 20a and the second nozzle 10a forming the lower ends of the heating funnel 10 and the ejection unit 20 respectively, and providing a slow cooling space 50' for a molded object formed with the workbench S as a supporting base. For example, in one embodiment of the present invention, the embedding block 40 and the heating chamber 50 may be connected up and down through an ejection hole 40", and the ejection hole 40" is used to allow the first material M1 and the second material M2 to flow from the first nozzle 20a and the second nozzle 10a to the slow cooling space 50' accommodating the workbench S.

[0128] In one embodiment of the present invention, the first material M1 and the second material M2 ejected from the heating funnel 10 and the ejection unit 20 embedded in the embedding block 40 can be accumulated on a workbench S provided in the slow cooling space 50' of the heating chamber 50, so that the embedding block 40 can be fluidly connected to the heating chamber 50 to allow the first material M1 and the second material M2 to flow. Throughout the present specification, the embedded block 40 and the heating chamber 50 are fluidly connected to each other, which means that the first material M1 and the second material M2 sprayed from the heating funnel 10 and the spray unit 20 embedded in the embedded block 40 can be accumulated on the workbench S set in the heating chamber 50. In this sense, the embedded block 40 and the heating chamber 50 are fluidly connected to each other, which means that the internal space of the heating funnel 10 embedded in the embedded block 40 (the internal space of the heating funnel 10 accommodating the second material M2) and the internal space of the spray unit 20 (the internal space of the spray unit 20 accommodating the first material M1) are connected to the slow cooling space 50' of the heating chamber 50 (the slow cooling space 50' accommodating the workbench S), thereby forming a space in which the internal space of the heating funnel 10, the internal space of the spray unit 20 and the slow cooling space 50' of the heating chamber 50 are all connected.

[0129] In one embodiment of the present invention, the slow cooling space 50' of the heating chamber 50 providing the support base of the molded object can be sealed by assembling the insert block 40 with the heating chamber 50. At this time, sealing the slow cooling space 50' of the heating chamber 50 by assembling the insert block 40 with the heating chamber 50 means that the insert block 40 and the heating chamber 50 can be fluidically connected to each other to form a space, and the space formed in this way, for example, the internal space of the heating funnel 10 containing the second material M2, the internal space of the ejection unit 20 containing the first material M1, and the slow cooling space 50' of the heating chamber 50 provided with the workbench S are fluidly connected to each other to form a space, and at the same time, along the up-down direction Z1, the space is sealed as the insert block 40 and the heating chamber 50 are assembled with each other. In one embodiment of the present invention, a sealing cover 1 for sealing the feed port of the heating funnel 10 may be provided on the feed port of the heating funnel 10 exposed at the upper end of the insert block 40. For example, the flow rate (volume passing through the cross-sectional area per unit time) or the ejection speed of the second material M2 ejected from the inner space of the heating funnel 10 to the second nozzle 10a forming the lower end of the heating funnel 10 may be controlled according to the pressure of the gas RG filled in the inner space of the heating funnel 10 sealed by the sealing cover 1 for sealing the inner space of the heating funnel 10. For example, in one embodiment of the present invention, a metal flow melted by a metal block and a gas RG exerting a predetermined pressure on the liquid surface of the metal flow, for example, a gas RG including air, may be filled in the inner space of the heating funnel 10. In one embodiment of the present invention, the flow rate (volume passing through the cross-sectional area per unit time) or the ejection speed of the second material M2 ejected from the second nozzle 10a forming the lower end of the heating funnel 10 may be controlled by increasing or decreasing the pressure of the gas RG. For example, the gas RG filled in the inner space of the heating funnel 10 may include an inert gas, which can control the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the metal flow while preventing the metal flow formed in the inner space of the heating funnel 10 from being oxidized. Thus, in one embodiment of the present invention, the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the liquid second material M2 can be controlled by the pressure of the gas RG filled in the inner space of the heating funnel 10, and the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the paste or slurry first material M1 can be controlled by the speed of the rotating screw 85 rotating inside the delivery pipe 83 of the extruder 80. Thus, in one embodiment of the present invention, the first material M1 and the second material M2 that form the contours of different objects and the objects themselves in different material phases can be controlled by different control mechanisms to control their flow rates (volume passing through a cross-sectional area per unit time) or ejection speeds.

[0130] In one embodiment of the present invention, the insert block 40 and the heating chamber 50 may form a space that is fluidly connected to each other, for example, a space may be sealed by assembling the insert block 40 and the heating chamber 50. In one embodiment of the present invention, the internal space of the heating funnel 10 whose temperature is set to the second temperature T2 of the melting point of the metal block or higher, the internal space of the ejection unit 20 whose temperature is set to the first temperature T1 lower than the melting point of the metal block but higher than the room temperature, and the slow cooling space 50' of the workbench S where the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a forming the lower end of the heating funnel 10 and the ejection unit 20 accumulate, may form a space that allows the first material M1 and the second material M2 to flow and be connected to each other, and the space connected to each other may be insulated from the outside by assembling the insert block 40 and the heating chamber 50. For example, the insert block 40 and the heating chamber 50 may be sealed and combined with each other through a stepped interface (stepped assembly portion ST1) to block the flow of internal hot air or external cold air. In one embodiment of the present invention, by respectively arranging different first heat sources 15 and second heat sources 55 in the embedded block 40 and the heating chamber 50 that form a sealed combination with each other, for example, the first heat source 15 and the second heat source 55 that are driven independently of each other, the second temperature T2 of the heating funnel 10 embedded in the embedded block 40 and the first temperature T1 of the ejection unit 20 and the slow cooling temperature of the shape formed on the workbench S or the third temperature T3 for slow cooling The temperature curve can be controlled independently of each other, and at the same time, a mutually sealed combination is formed through the stepped interface (assembly parts ST1, ST2) between the embedded block 40 and the heating chamber 50, so that a space formed by the embedded block 40 and the heating chamber 50 that are fluidly connected to each other for the ejection of the first material M1 and the second material M2 is tightly sealed and insulated from the surrounding environment. According to the present specification, a space formed by the embedded block 40 and the heating chamber 50 formed by assembling the embedded block 40 and the heating chamber 50, for example, a space formed by the internal space of the heating funnel 10 embedded in the embedded block 40, the internal space of the ejection unit 20 and the slow cooling space 50' inside the heating chamber 50 are fluidly connected to each other and is sealed, or insulated from the surrounding environment by blocking the flow of hot air and cold air in and out. This is based on the premise of sealing the feed port of the heating funnel 10 exposed at the upper end of the embedded block 40. In one embodiment of the present invention, a sealing cover 1 can be provided on the feed port of the heating funnel 10. On the other hand, since a connecting tube body 70 connected to the ejection port 80a of the extrusion device 80 is inserted into the mating end 20b of the ejection unit 20 exposed at the upper end of the embedded block 40, in order to block the flow of internal hot air or external cold air through the feed port of the heating funnel 10 exposed at the upper end of the embedded block 40 and the mating end 20b of the ejection unit 20, the feed port of the heating funnel 10 exposed at the upper end of the embedded block 40 and the mating end 20b of the ejection unit 20 can be insulated from the surrounding environment.

[0131] In one embodiment of the present invention, the assembly of the embedded block 40 and the heating chamber 50 may include a sealed combination between the embedded block 40 and the heating chamber 50. In one embodiment of the present invention, the embedded block 40 and the heating chamber 50 may form a sealed combination with each other through a stepped interface (assembly portion ST1, ST2). More specifically, the embedded block 40 may include an assembly portion ST1 with the heating chamber 50 formed on the bottom wall of the embedded block 40 (lower block 42) defining the upper part of the heating chamber 50, and the heating chamber 50 may include a partition wall 50a, and the partition wall 50a is arranged to abut against the stepped surface of the assembly portion ST1. For example, in one embodiment of the present invention, the embedded block 40 may include an upper block 41 formed to be relatively high to embed most of the heating funnel 10 and the ejection unit 20, and a lower block 42 formed by expanding the area from the upper block 41, and the bottom of the lower block 42 may be formed with an assembly portion ST1 for sealing and combining with the heating chamber 50. For example, in one embodiment of the present invention, the assembly part ST1 may include a stepped surface formed along the edge of the lower block 42, and the partition wall 50a of the heating chamber 50 may be vertically assembled to abut against the stepped surface of the assembly part ST1, thereby forming a slow cooling space 50' surrounded by the lower block 42 of the embedded block 40 and the partition wall 50a of the heating chamber 50. A second heat source 55 may be formed on the partition wall 50a of the heating chamber 50 forming the slow cooling space 50'. The second heat source 55 can be accommodated in the accommodating channel 50"' of the partition 50a forming the slow cooling space 50', forming a workbench S surrounding the support base for providing the modeling object, and can control the cooling rate of the first material M1 and the second material M2 accumulated on the workbench S from the first nozzle 20a and the second nozzle 10a. More specifically, in one embodiment of the present invention, a solid modeling object can be formed by cooling the liquid metal flow filled in the filling space FS surrounded by the outline of the modeling object formed by the first material M1. At this time, since the cooling rate deviation of the liquid metal flow forming the modeling object itself may cause local thermal stress accumulation, the temperature curve (the temperature curve of the third temperature T3) that decreases per unit time can be slowly controlled to induce uniform cooling. The second heat source 55 can control the temperature of the slow cooling space 50' (the third temperature T3) so that the temperature of the slow cooling space 50' of the workbench S accommodating the accumulation of the first material M1 and the second material M2 can achieve the annealing heat treatment effect.In one embodiment of the present invention, the second heat source 55 can control the cooling rate of the liquid second material M2 so that the cooling rate of the second material M2 that fills the filling space FS surrounded by the outline of the shape formed by the first material M1 follows a slow curve (a temperature curve of the third temperature T3) per unit time, and by controlling the temperature (third temperature T3) of the slow cooling space 50' of the workbench S that accommodates the first material M1 and the second material M2 sprayed together, the third temperature T3 of the slow cooling space 50' of the workbench S that accommodates the first material M1 and the second material M2 sprayed together can be controlled to avoid the second material M2 in contact with the relatively low temperature first material M1 due to the contact between the first material M1 and the second material M2. The heat treatment effect of quenching. In one embodiment of the present invention, the second material M2 ejected at a second temperature T2 of the melting point of the metal block or higher may be in a liquid state and have relatively sufficient fluidity, but the first material M1 in a paste or slurry state with ceramic particles dispersed therein may be relatively lacking in fluidity. For this reason, the temperature of the first material M1 or the ejection unit 20 containing the first material M1 may be set to a first temperature T1 lower than the second temperature T2, for example, it may be set to a sufficiently low temperature to prevent the matrix with ceramic particles dispersed therein (for example, water H2O as a carrier that gives the ceramic particles fluidity) from vaporizing or volatilizing. For example, in one embodiment of the present invention, the first temperature T1 of the first material M1 ejected onto the workbench S and the second temperature T2 of the second material M2 may satisfy the relationship of the second temperature T2> the first temperature T1, at which time, the first temperature T1 may correspond to a sufficiently low temperature that does not cause the matrix of the first material M1 to vaporize or volatilize, and the third temperature T3 of the slow cooling space 50' may be set to a temperature higher than the first temperature T1, so as to form the outline of a solid or nearly solid object by vaporizing or volatilizing the matrix H2O with ceramic particles dispersed therein. For example, in one embodiment of the present invention, the first temperature T1 of the first material M1 ejected onto the workbench S or the ejection unit 20 containing the first material M1, the second temperature T2 of the second material M2 ejected onto the workbench S or the heating funnel 10 containing the second material M2, and the third temperature T3 of the slow cooling space 50' containing the workbench S can satisfy the magnitude relationship of second temperature T2>third temperature T3>first temperature T1. In one embodiment of the present invention, the second temperature T2 can correspond to the highest temperature of the melting point of the metal block or higher in a 3D printing device including different spaces with different target temperatures (for example, the first temperature T1 to the third temperature T3), can be kept constant over time with the melting point of the metal block or higher target temperature as input, and can be kept constant according to the control of the first heat source 15.With the first heat source 15 as the heat source and embedded together with the first heat source 15, and by interposing a thermal resistance formed by the insulating material of the embedded block 40 filling the gap g between the first nozzle 20a and the second nozzle 10a, the first temperature T1 of the ejection unit 20 separated from the heating funnel 10 or the first heat source 15 surrounding the outer peripheral surface of the heating funnel 10 can also be kept constant over time similar to the second temperature T2. For example, the first temperature T1 of the ejection unit 20 can also be kept constant over time by the insulating material of the embedded block 40 filling the gap g between the first nozzle 20a and the second nozzle 10a to provide a constant second temperature T2 and a constant thermal resistance.

[0132] In this way, different from the first temperature T1 and the second temperature T2 of the respective heating funnel 10 and the ejection unit 20, the third temperature T3 of the slow cooling space 50' of the heating chamber 50 can be controlled to achieve a slow temperature curve over time, and the second heat source 55 can be set to a temperature that gradually decreases according to the temperature curve that changes over time by controlling it, so as to follow the preset slow temperature curve, that is, to follow the slow temperature curve and induce the annealing heat treatment effect, accordingly, the third temperature T3 of the slow cooling space 50' of the heating chamber 50 can be different from the first temperature T1 and the second temperature T2, corresponding to the temperature that changes over time. As mentioned above, the first temperature T1 to the third temperature T3 can satisfy the magnitude relationship of the second temperature T2> the third temperature T3> the first temperature T1, at this time, the third temperature T3 can correspond to the highest temperature in the temperature curve that slowly decreases over time. For example, in one embodiment of the present invention, the slow cooling space 50' of the heating chamber 50 can be maintained at a constant third temperature T3 during the continuous ejection of the first material M1, can be maintained at a relatively high temperature suitable for gasification or volatilization of the matrix in the first material M1 ejected onto the workbench S, and gradually decrease the third temperature T3 when entering the slow cooling interval of slowly decreasing the third temperature T3. At this time, the third temperature T3 can be maintained at the highest temperature suitable for gasification or volatilization of the matrix in the first material M1 during the interval of continuously ejecting the first material M1 onto the workbench S (or the interval of continuously ejecting at least one of the first material M1 and the second material M2), until the ejection of the first material M1 is completed and the ejection of the second material M2 that fills the filling space FS surrounded by the outline of the object of the first material M1 is completed, and the appearance of the object of the object is substantially formed, and then the slow cooling interval of slowly decreasing the third temperature T3 is entered. If, on the contrary, the third temperature T3 of the slow cooling space 50' of the heating chamber 50 accommodating the workbench S is lowered while the first material M1 and the second material M2 are continuously sprayed onto the workbench S, this is contrary to the purpose of the slow temperature curve of the slow cooling, namely, inducing uniform cooling inside the molded object and eliminating thermal stress or residual stress caused by cooling rate deviation. Instead, it may cause cooling rate deviation inside the molded object and cause thermal stress or residual stress according to the cumulative order of each layer (for example, each layer of the second material M2) sprayed onto the workbench S.

[0133] According to an embodiment of the present invention, a 3D printing device may include different spaces controlled by different first temperatures T1 to third temperatures T3. The first temperatures T1 to third temperatures T3 may have a magnitude relationship as described above. At this time, the first temperature T1 and the second temperature T2 may remain constant over time, and the third temperature T3 may follow a slow temperature curve for slow cooling of the object. At this time, the third temperature T3, which is a comparison object with the first temperature T1 and the second temperature T2 maintained constant, may correspond to the highest temperature in the slow temperature curve for slow cooling (for example, the highest temperature maintained in the interval of continuous spraying of the first material M1 and the second material M2).

[0134] As described above, the embedded block 40 and the heating chamber 50 assembled along the up-down direction Z1 can be fluidly connected to each other to allow the first material M1 and the second material M2 to be ejected. More specifically, the embedded block 40 and the heating chamber 50 can be fluidly connected to each other through a ejection hole 40" for ejecting the first material M1 and the second material M2. The ejection hole 40" can be formed in the lower block 42 connected to the upper block 41 embedded in most of the heating funnel 10 and the ejection unit 20, and can include two different ejection holes 40" connected to the first nozzle 20a and the second nozzle 10a that respectively form the lower ends of the heating funnel 10 and the ejection unit.

[0135] In one embodiment of the present invention, the embedding block 40 may include: an upper block 41 formed to be relatively high to embed the majority of the heating funnel 10 and the ejection unit 20; and a lower block 42 formed to have an extended area with a relatively low height at the lower part of the upper block 41 to cover the slow cooling space 50' of the heating chamber 50. For example, in one embodiment of the present invention, the upper block 41 and the lower block 42 may be generally formed in a hexahedral shape, and may include an upper block 41 formed to be relatively high and a lower block 42 formed in an extended plate shape from the upper block 41 to be relatively low in height.

[0136] For the first material M1, the first material M1 can be formed by a paste-like or slurry-like composite material formed by mixing solid ceramic particles and a liquid matrix in which ceramic particles are dispersed. For example, the ceramic particles can have a particle size of micrometers (μm). In one embodiment of the present invention, the ceramic particles may include a mixture of ceramic particles of different sizes. By mixing ceramic particles of different particle sizes, appropriate gaps can be ensured between ceramic particles of different particle sizes to provide a space for accommodating the matrix. The ceramic particles of different particle sizes accumulated on the workbench S fill the gaps. For example, ceramic particles of relatively small particle sizes fill the gaps between ceramic particles of relatively large particle sizes, so that the first material M1 mixed with ceramic particles of different particle sizes forms a contour of a modeling object with a firm shape stability (for example, a high degree of stability provided by a combination of particles of different sizes filling the gaps) through the gasification or volatilization of the matrix. On the other hand, in one embodiment of the present invention, the first material M1 may include solid ceramic particles and water (H2O) as a matrix for accommodating dispersed ceramic particles. In one embodiment of the present invention, the matrix may include dispersed ceramic particles to give the ceramic particles fluidity. Since the first material M1 is formed in a paste or slurry state with dispersed ceramic particles, its fluidity may be lower than that of the second material M2 formed as liquid metal or metal flow. In order to form a uniform mixture (or a uniform concentration dispersion) between ceramic particles (solid) having different material phases and the matrix (liquid or gel) contained in the ceramic particles, the first material M1 can be forcibly conveyed by extrusion through a spraying unit 20 including a first nozzle 20a at the lower end for spraying the first material M1 and a connecting tube body 70 connected to the mating end 20b of the spraying unit 20.

[0137] In one embodiment of the present invention, a metal block with a low melting point, which is a raw material of the second material M2 (second raw material), can be put into a heating funnel 10 connected to a second nozzle 10a that ejects the second material M2, and the heating funnel 10 is heated to the melting point of the metal block or a higher temperature, thereby forming a liquid metal flow for forming the second material M2. For example, in one embodiment of the present invention, the metal block with a low melting point, which is a raw material of the second material M2 (second raw material), can be formed into a disc-like shape with a relatively low height and an elongated size, wherein the longest dimension of the low melting point metal block can correspond to the diameter of the disc, and the diameter of the low melting point metal block can be about 50 mm. In one embodiment of the present invention, the heating funnel 10 that takes the low-melting-point metal block as input and ejects the metal flow can be formed into a substantially Y-shaped funnel shape, and the inner diameter of the second nozzle 10a that ejects the metal flow can be formed to be smaller than the inner diameter of the feed port into which the low-melting-point metal block is inserted. In other words, the inner diameter of the feed port into which the low-melting-point metal block is inserted can be formed to be larger than the longest dimension of the low-melting-point metal block. On the contrary, the inner diameter of the second nozzle 10a that ejects the metal flow formed by the low-melting-point metal block melted in the heating funnel 10 can be formed to be smaller than the longest dimension of the low-melting-point metal block. More specifically, the longest dimension of the low-melting-point metal block can correspond to the diameter of the disk in the disk shape of the low-melting-point metal block. When the diameter of the disk is about 50 mm, in one embodiment of the present invention, the inner diameter of the second nozzle 10a can be formed to be smaller than the diameter of the solid disk of 50 mm, and is 0.1 mm to 4 mm, for example, it can be formed to be about 1 mm to 2 mm.

[0138] In one embodiment of the present invention, the first nozzle 20a and the second nozzle 10a can be embedded and positioned in a single embedding block 40 by interposing a predetermined interval therebetween, and the first nozzle 20a and the second nozzle 10a are positioned adjacent to each other by the embedding block 40. For example, the heating funnel 10 and the ejection unit 20, which respectively include the first nozzle 20a and the second nozzle 10a at the lower end opposite to the workbench S, can be arranged in the embedding block 40 to maintain a constant interval with each other. For example, in order to maintain a constant interval at different levels along the height direction Z1, the heating funnel 10 can be formed into a Y-shaped funnel shape, and the ejection unit 20 can extend along an oblique direction that simultaneously follows the height direction Z1 and the radial directions Z2 and Z3 to be parallel to the outer peripheral surface of the heating funnel 10. For example, in one embodiment of the present invention, the outer peripheral surface of the heating funnel 10 and the ejection unit 20 can extend along an oblique direction that simultaneously follows the height direction Z1 and the radial directions Z2 and Z3, and then form the first nozzle 20a and the second nozzle 10a at the lower end that extend vertically toward the workbench S along the height direction Z1. For example, the heating funnel 10 may form a deformation point of a bottleneck connected to the second nozzle 10a, and the ejection unit 20 may form a bending deformation point connected to the first nozzle 20a.

[0139] In one embodiment of the present invention, the interval g between the first nozzle 20a and the second nozzle 10a ensured by the insert block 40 may be about 3 mm to 50 mm, for example, the interval g between the first nozzle 20a and the second nozzle 10a may be about 25 mm. As described below, in one embodiment of the present invention, the interval g between the first nozzle 20a and the second nozzle 10a ensured by the embedded block 40 can be based on the driving mode of the first nozzle 20a and the second nozzle 10a. For example, unlike the driving mode in which the first nozzle 20a and the second nozzle 10a are started in a chronological relationship, in the driving mode in which the first nozzle 20a and the second nozzle 10a are started simultaneously, the interval formed between the ejection positions P1 and P2 of the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a corresponding to the interval between the first nozzle 20a and the second nozzle 10a can be filled by the liquid metal flow of the second material M2 ejected from the second nozzle 10a. For example, the interval between the first ejection position P1 and the second ejection position P2 can be filled by the metal flow of the second material M2 flowing from the second ejection position P2 of the second material M2 to the first ejection position P1 of the first material M1. For example, in one embodiment of the present invention, the first material M1 and the second material M2 that respectively form the outline of the sculpted object and the sculpted object itself are ejected together onto the workbench S by simultaneously starting the first nozzle 20a and the second nozzle 10a. Unlike the first material M1 with insufficient fluidity, the second material M2 with relatively sufficient fluidity can flow from the ejection position P2 of the second material M2 to the ejection position P1 of the first material M1, and while filling the filling space FS surrounded by the outline of the sculpted object formed by the first material M1, no void is formed inside the sculpted object. Thus, in the driving mode in which the first nozzle 20a and the second nozzle 10a are simultaneously activated, the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a together can abut against each other to form contact, and accordingly, in one embodiment of the present invention, by embedding the heating funnel 10 and the ejection unit 20 including the first nozzle 20a and the second nozzle 10a at the lower end ejecting the first material M1 and the second material M2, and by embedding the first heat source 15 together with the heating funnel 10 and the ejection unit 20, the first temperature T1 and the second temperature T2 of the respective first material M1 and the second material M2 can be controlled. In other words, the first temperature T1 and the second temperature T2 that are higher than the room temperature but different can be controlled by the activation of the first heat source 15 and the insulating material of the embedment block 40 between the heating funnel 10 and the ejection nozzle (preventing the second material M2 from being rapidly cooled due to the contact between the first material M1 and the second material M2).

[0140] For example, in a driving mode in which the first nozzle 20a and the second nozzle 10a are started simultaneously, the gap g between the first nozzle 20a and the second nozzle 10a can be determined based on the flow characteristics of the second material M2, such as the fluidity of the second material M2 ejected from the second nozzle 10a (for example, the viscosity or viscosity of the second material M2 that determines the fluidity) and the flow rate of the second material M2 (for example, the inner diameter of the second nozzle 10a that determines the flow rate or the pressure of the second nozzle 10a, etc.). For example, as the fluidity of the second material M2 increases and the flow rate of the second material M2 increases, the gap g between the first nozzle 20a and the second nozzle 10a can be designed to increase. Even if the gap g between the first nozzle 20a and the second nozzle 10a increases slightly, the gap between the ejection positions P1 and P2 of the first material M1 and the second material M2 corresponding to the gap g between the first nozzle 20a and the second nozzle 10a can be fully filled based on the relatively high fluidity and flow rate. On the contrary, as the fluidity of the second material M2 decreases and the flow rate of the second material M2 decreases, the gap g between the first nozzle 20a and the second nozzle 10a can be designed to decrease, and the gap g between the first nozzle 20a and the second nozzle 10a can be formed to be narrow enough so that even when the fluidity and flow rate of the second material M2 are relatively low, the gap between the ejection positions P1 and P2 of the first material M1 and the second material M2 corresponding to the gap g between the first nozzle 20a and the second nozzle 10a can be fully filled.

[0141] In one embodiment of the present invention, the fluidity of the second material M2 can be controlled by a first heat source 15 for forming a liquid second material M2 with a metal block as input, and the flow rate of the second material M2 can be controlled according to the pressure of the gas RG injected into the feed port of the heating funnel 10 including the second nozzle 10a at the lower end from which the second material M2 is ejected, or the pressure of the gas RG applied to the liquid surface of the second material M2 at the feed port. For example, in one embodiment of the present invention, a sealing cover 1 can be placed on the feed port of the heating funnel 10, and a gas RG for blocking oxidation of the second material M2 can be injected between the sealing cover 1 and the liquid surface of the second material M2 filled in the feed port. In addition, by controlling the pressure of the gas RG that pressurizes the liquid surface of the second material M2 to the second nozzle 10a, the flow rate of the second material M2 ejected from the second nozzle 10a can be controlled.

[0142] In one embodiment of the present invention, in order to prevent voids from being generated in the object to be shaped, it may be necessary to fill the gap between the ejection positions P1 and P2 of the first material M1 and the second material M2 formed by the gap g between the first nozzle 20a and the second nozzle 10a. The gap g between the first nozzle 20a and the second nozzle 10a can be designed to be a sufficiently narrow gap to fill the gap between the ejection positions P1 and P2 of the first material M1 and the second material M2 by the fluidity and flow rate of the second material M2 ejected from the second nozzle 10a.

[0143] In one embodiment of the present invention, in order to reduce the maximum stroke for driving the workbench S to translate along a two-dimensional plane, the gap g between the first nozzle 20a and the second nozzle 10a can be designed to be narrow enough so that the slice cross-sectional data of the three-dimensional object to be molded is used as an input to control the first ejection position P1 and the second ejection position P2 of the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a onto the workbench S to the first target position and the second target position, respectively. In one embodiment of the present invention, in order to form the same molded object, the first ejection position P1 of the first material M1 for forming the outline of the molded object and the second ejection position P2 of the second material M2 for forming the molded object itself on the workbench S can be controlled to the same first target position and the second target position, respectively, and as the gap g between the first nozzle 20a and the second nozzle 10a increases, the stroke of the workbench S for controlling the first ejection position P1 and the second ejection position P2 to the same first target position and the second target position, respectively, can be increased. In other words, as the interval g between the first nozzle 20a and the second nozzle 10a increases, the stroke of the workbench S required for making the same object needs to be extended to a larger span. On the contrary, as the interval g between the first nozzle 20a and the second nozzle 10a decreases, the stroke of the workbench S required for making the same object can be reduced to a smaller span. Moreover, for the stroke of the workbench S with the same span, a larger volume of the object can be made. For example, the extension of the stroke of the workbench S to a larger span means that, for example, the driving width or span of the second actuator A2 and the third actuator A3 for driving the workbench S in translation on a two-dimensional plane needs to be extended, and because the size of the slow cooling space 50' accommodating the workbench S needs to be extended more widely, the cost of the printing device will increase even if the same manufacturing capacity of forming objects of the same size is provided. For example, when the gap g between the first nozzle 20a and the second nozzle 10a is designed to be different, the conveying amount of the workbench S required to move the second nozzle 10a to the target position where the first nozzle 20a is located or the second nozzle 10a to the target position on the workbench S opposite to the first nozzle 20a can be shortened accordingly as the gap between the first nozzle 20a and the second nozzle 10a is narrower (see Fig.14 ).

[0144] In one embodiment of the present invention, the thermal resistance formed by the insulating material of the insert block 40 filling the gap g between the first nozzle 20a and the second nozzle 10a can be changed according to the gap g between the first nozzle 20a and the second nozzle 10a, and accordingly, the temperature difference between the first temperature T1 and the second temperature T2 of the heating funnel 10 and the ejection unit 20 including the first nozzle 20a and the second nozzle 10a at the lower end for ejecting the first material M1 and the second material M2 can be affected. For example, the second temperature T2 of the heating funnel 10 can be directly controlled by the first heat source 15 surrounding the outer peripheral surface of the heating funnel 10, but the first temperature T1 of the ejection unit 20 can be indirectly controlled according to the distance from the heating funnel 10 or the distance from the first heat source 15 surrounding the outer peripheral surface of the heating funnel 10, and the first temperature T1 of the ejection unit 20 can be controlled according to the distance between the heating funnel 10 and the ejection unit 20 extending in parallel to each other or the distance between the first nozzle 20a and the second nozzle 10a forming the lower ends of the respective heating funnel 10 and the ejection unit 20. In one embodiment of the present invention, the first temperature T1 of the ejection unit 20 ejecting the first material M1 can be formed to be a sufficiently low temperature to suppress the vaporization or volatilization of the matrix included in the first material M1, and at the same time be formed to be a sufficiently high temperature to suppress the rapid cooling of the liquid second material M2 that abuts against the first material M1 that forms the contour of the object on the workbench S and forms the object itself. In order to control the first temperature T1 of the first material M1 at an appropriate level, the gap g between the first nozzle 20a and the second nozzle 10a can be appropriately designed. For example, the gap g between the first nozzle 20a and the second nozzle 10a can be designed according to the following different viewpoints, for example, 1) the gap g between the first nozzle 20a and the second nozzle 10a is designed to be narrow enough to shorten the stroke of the workbench S used to form the same object, and as a compromise, 2) the thermal resistance formed by the insulating material of the embedded block 40 filling the first nozzle 20a and the second nozzle 10a is appropriately designed, for example, the gap g between the first nozzle 20a and the second nozzle 10a can be formed to be wide enough to suppress the vaporization or volatilization of the matrix included in the first material M1 (suppress the vaporization or volatilization of the matrix caused by the excessively high first temperature T1).

[0145] In one embodiment of the present invention, the heating funnel 10 that takes a solid metal block as an input and ejects a liquid metal flow can be formed into a roughly Y-shaped funnel shape, wherein the inner diameter of the second nozzle 10a ejecting the liquid metal flow is smaller than the inner diameter of the feed port into which the solid metal block is inserted. In one embodiment of the present invention, the heating funnel 10 is formed into a Y-shaped funnel shape, which means that the cross-sectional area decreases in the process from the feed port at the upper end of the heating funnel 10 to the second nozzle 10a at the lower end of the heating funnel 10, and the second nozzle 10a from the upper end to the lower end has a funnel shape with a circular cross-section. For example, in one embodiment of the present invention, the second nozzle 10a can eject the second material M2 through a circular cross-sectional area with a definable inner diameter. For example, the heating funnel 10 can be formed so that the inner diameter gradually decreases from the feed port at the upper end to the second nozzle 10a at the lower end along the height direction Z1, and a bottleneck with a minimum inner diameter is formed in the second nozzle 10a, and the second nozzle 10a can be formed to have a constant inner diameter.

[0146] In one embodiment of the present invention, a first heat source 15 for heating a metal block put into the heating funnel 10 to a melting point or higher may be wound on the outer circumferential surface of the heating funnel 10. In one embodiment of the present invention, the first heat source 15 wound on the outer circumferential surface of the heating funnel 10 may form a maximum second temperature T2 of the melting point of the metal block or higher, and the second heat source 55 formed in the heating chamber 50 accommodating the workbench S ejecting the second material M2 through the heating funnel 10 may form a third temperature T3 lower than the second temperature T2. For example, in one embodiment of the present invention, the second temperature T2 may be set to the melting point of the metal block or higher, and the third temperature T3 may be set to a temperature lower than the second temperature T2 but high enough to vaporize or volatilize the matrix containing the dispersed plurality of ceramic particles of the first material M1 formed into a paste or slurry. Furthermore, the first temperature T1 of the ejection unit 20 containing the first material M1 can be set to a temperature lower than the second temperature T2 and the third temperature T3, that is, a temperature higher than room temperature but low enough to suppress the vaporization or volatilization of the matrix that provides fluidity to the first material M1. For example, the temperature can be maintained at a temperature lower than the third temperature T3 in the heating chamber 50 that can induce vaporization or volatilization of the matrix of the first material M1 accumulated on the workbench S.

[0147] In one embodiment of the present invention, the heating funnel 10 may be formed of a ceramic material having electrical insulation, thermal insulation and fire resistance. The first heat source 15 may be formed in a form wound along the outer circumference of the heating funnel 10, and may be formed in a form continuously wound along the outer circumference of the heating funnel 10 in a spiral shape. For example, the first heat source 15 may be a heating wire wound on the outer circumference of the heating funnel 10. In one embodiment of the present invention, a concave accommodating channel 40' for accommodating the heating wire forming the first heat source 15 may be formed in the outer circumference of the heating funnel 10 and / or in the embedded block 40 opposite to the outer circumference of the heating funnel 10, and the concave accommodating channel 40' may be formed along the outer circumference of the heating funnel 10 and extend continuously in a spiral shape. In one embodiment of the present invention, the first heat source 15 may be a heating wire wound on the outer circumference of the heating funnel 10. By winding on the outer circumference of the heating funnel 10 having electrical insulation, the current of the heating wire or the electromagnetic force induced by the current will not interfere with the flow of the metal flow contained in the heating funnel 10. For example, in one embodiment of the present invention, the heating funnel 10 forms electrical insulation between the internal space of the heating funnel 10 filled with the second material M2 and the outer peripheral surface of the heating funnel 10 wrapped with the first heat source 15, thereby providing insulation to eliminate electromagnetic influences between the flow of the metal flow filled in the internal space of the heating funnel 10 and the heating wire wrapped on the outer peripheral surface of the heating funnel 10, for example, electromagnetic influences that may hinder the flow of the metal flow.

[0148] The first heat source 15 may be connected to the first switch to control the temperature (second temperature T2) of the internal space of the heating funnel 10, and the activation of the heating wire may be turned on and off by the on-off control of the first switch, so that the temperature of the internal space of the heating funnel 10 may be set to the second temperature T2 of the melting point of the metal block or higher. For example, according to the on-off control of the switch, a DC current (constant current) of a constant magnitude may flow through the first heat source 15, and by the on-off control of the DC current of a constant magnitude, an intermittent flow of a DC current of a constant magnitude may be formed, and in order to generate electromagnetic force by the flow of AC current and induce intermittent flow of the second nozzle 10a at the lower end of the heating funnel 10, for example, in order to induce dripping in the form of droplets, there may be a difference in the configuration of the wire to which the AC current is applied.

[0149] Similar to the heating funnel 10, the embedding block 40 may be formed of a ceramic material having electrical insulation, thermal insulation and fire resistance. The embedding block 40 may be formed in a substantially hexahedral shape, and the hexahedral embedding block 40 may include: an upper block 41 formed to be relatively high to embed the heating funnel 10 and most of the ejection unit 20; and a lower block 42 formed in a plate shape with an area extended from the upper block 41. In addition, in the stepped area between the upper block 41 and the lower block 42 of the embedding block 40, that is, in the stepped area formed between the upper surface of the lower block 42 and the side surface of the upper block 41, an extrusion device 80 connected to the ejection unit 20 by interposing a connecting tube body 70 between the mating end 20b of the ejection unit 20 may be provided.

[0150] The lower block 42 can form a slow cooling space 50' together with the next door 50a of the heating chamber 50, and more specifically, the upper part of the slow cooling space 50' can be defined. For example, a stepped assembly part ST1 can be formed at the four edges of the lower block 42, and the stepped assembly part ST1 forms a stepped interface with the next door 50 of the heating chamber 50 and is combined. For example, the upper corners of the next door 50a of the heating chamber 50 can be abutted and assembled with the stepped assembly part ST1 of the lower block 42, and a sealed combination through the stepped interface is formed between the heating chamber 50 and the lower block 42. On the other hand, in one embodiment of the present invention, the heating chamber 50 can include a total of 4 next doors 50a that are relatively arranged along different second directions Z2 and third directions Z3, respectively, and the next doors 50a that are assembled to form corners and abut each other can also form a stepped interface with each other through the stepped assembly part ST2 to form a sealed combination.

[0151] The heating chamber 50 may be formed of a ceramic material having electrical insulation, thermal insulation and fire resistance. The heating chamber 50 may be formed in a substantially hexahedral shape, and a workbench S may be accommodated in the slow cooling space 50' of the heating chamber 50 formed in a hexahedral shape, and the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a are accumulated on the workbench S. The heating chamber 50 may include four partitions 50a surrounding the periphery of the slow cooling space 50', and the four partitions 50a forming the heating chamber 50 may be assembled in contact with the assembly part ST1 of the lower block 42 defining the upper part of the slow cooling space 50', thereby forming the heating chamber 50 providing the slow cooling space 50'. The heating chamber 50 may also include a bottom wall 50b, and the bottom wall 50b defines the lower part of the slow cooling space 50' while providing an assembly position for installing the four partitions 50a. An opening 50'' is formed on the bottom wall 50b of the heating chamber 50 to allow power connection between the workbench S and the actuator A (the first actuator A1 to the third actuator A3), and the connecting rod 100 can pass through the opening 50'' and realize power connection between the workbench S and the actuator A. The connecting rod 100 realizes mutual power connection between the workbench S and the actuator A that provides driving power to the workbench S through the opening 50''.

[0152] The connecting rod 100 that realizes the power connection between the workbench S and the actuator A (the first actuator A1 to the third actuator A3) can generate three-dimensional movement of the workbench S while following the lifting and lowering movement of the actuator A and the translational movement on the two-dimensional plane. At this time, the connecting rod structure L connected to the bellows cover ZC can adaptively expand and contract the distance between the guide block GB (for example, the guide block GB of the third actuator A3) and the bellows cover ZC, and always seal the opening 50" of the bottom wall 50b regardless of the drive of the actuator A (the first actuator A1 to the third actuator A3) to block the outflow and inflow of internal hot air and external cold air. The guide block GB rises and falls according to the drive of the actuator A (the first actuator A1 to the third actuator A3), and the bellows cover ZC is superimposed on the bottom wall 50b of the heating chamber 50 and seals the opening 50" of the bottom wall 50b.

[0153] The opening 50" formed on the bottom wall 50b of the heating chamber 50 can be sealed regardless of the lifting drive of the actuator A by a bellows cover ZC covering the opening 50". The bellows cover ZC connected to the connecting rod structure L extending parallel to the connecting rod 100 connecting the actuator A (for example, the guide block GB of the third actuator A3) and the workbench S and adaptively extending and retracting between the actuator A (for example, the guide block GB of the third actuator A3) and the bottom wall 50b of the heating chamber 50 can seal the opening 50" regardless of the lifting drive of the actuator A.

[0154] Although not shown in the figure, the ejection unit 20 embedded in the embedding block 40 together with the heating funnel 10 may be formed of different heterogeneous materials, for example, it may include a core of a metal material forming the appearance of the ejection unit 20 and a ceramic shell surrounding the core, which are formed of different heterogeneous materials. In one embodiment of the present invention, the core of the metal material forms the skeleton of the ejection unit 20, can form a smooth surface (or inner diameter) for discharging the first material M1, and can be formed of a metal material such as stainless steel having excellent formability, and the shell surrounding the core of the metal material can be formed of a ceramic material having electrical insulation, thermal insulation and fire resistance. In one embodiment of the present invention, since the core of the ejection unit 20 is formed of a metal material, the ejection unit 20 can form the temperature of the ejection unit 20 to a first temperature T1 higher than room temperature according to the heat transfer from the first heat source 15 surrounding the outer peripheral surface of the heating funnel 10, and at the same time, by forming a ceramic shell around the outside of the core, it can be formed of a ceramic material that is the same as or similar to the embedded block 40 in which the heating funnel 10 and the ejection unit 20 are embedded together, thereby forming a close contact between each other, fundamentally eliminating the problem of separation of dissimilar materials due to different material properties. For example, in one embodiment of the present invention, by forming the heating funnel 10 and the ejection unit 20 embedded together in the embedded block 40 with a ceramic material that is the same as or similar to the embedded block 40, the separation problem between dissimilar materials with different material properties can be prevented. Similarly, the embedded block 40 and the heating chamber 50, which together form the slow cooling space 50' of the heating chamber 50 through close contact, can also be formed of the same or similar ceramic material, thereby blocking the outflow and inflow of hot air and cold air between the inside and outside of the slow cooling space 50' through the close contact between them.

[0155] In one embodiment of the present invention, the embedding block 40 and the heating chamber 50 may be formed into a hexahedron shape to form a close connection with each other. In various embodiments of the present invention, the embedding block 40 and the heating chamber 50 may also be formed into various polygonal or circular shapes other than a hexahedron. In one embodiment of the present invention, the heating chamber 50 may accommodate a workbench S that provides a support base for the modeling object to provide a position for cooling the modeling object formed on the workbench S. In one embodiment of the present invention, a metal flow of a second material M2 used to form the modeling object itself may be formed by heating and melting a low-melting-point metal block, and the modeling object may be formed by allowing the metal flow thus formed to fill the filling space FS surrounded by the outline of the modeling object of the first material M1, and a solid modeling object may be formed by cooling, more specifically, by slowly cooling the liquid metal flow filled in the filling space FS surrounded by the outline of the first material M1. By cooling the liquid metal flow to form a solid object in this way, internal defects such as voids inside the object can be eliminated. For example, compared with the comparative example of using a paste or slurry second material M2 formed by a mixture of metal powder, a carrier for imparting fluidity and an adhesive for controlling viscosity as the second material M2 for forming the object itself, spraying it onto a workbench S to form the appearance of the object, and then sintering the paste or slurry second material M2 by laser irradiation to complete the solid object, an object with reduced internal defects such as voids can be formed.

[0156] In one embodiment of the present invention, a solid object is formed by filling a filling space FS surrounded by a first material M1 forming the outline of the object with a liquid metal flow and cooling the liquid metal flow, so that an object with reduced internal defects such as voids can be formed, and by cooling the object in a heating chamber 50 in which a third temperature T3 of a slow cooling space 50' can be controlled to control the cooling rate of the object formed by the liquid metal flow, slow cooling of the object can be induced, and in particular, the cooling rate of the object can be controlled by controlling the third temperature T3 of the slow cooling space 50' of the heating chamber 50 accommodating a workbench S providing a support base for the object, and by cooling the object at a relatively low cooling rate that can be used for annealing heat treatment, residual stress such as thermal stress that may be accumulated inside the object due to cooling deviation caused by the position of the object can be eliminated. For example, the cooling rate for annealing heat treatment may have a relatively slow slope in a temperature curve that decreases per unit time, while the cooling rate for quenching heat treatment may have a steep slope in a temperature curve that decreases per unit time. If the cooling rate of the object cannot be controlled unlike the present invention, for example, the object is not cooled slowly according to a slow temperature curve, for example, it is cooled rapidly as in the case of cooling the object at room temperature, or the object is cooled rapidly according to a sharp temperature curve, then a quenching heat treatment will be performed instead of an annealing heat treatment, so that thermal stress or residual stress may be induced by a local temperature deviation inside the object, and the object has brittleness that is very vulnerable to external impact due to the quenching heat treatment, and is easily broken or damaged by external impact. In one embodiment of the present invention, a solid object is formed by slowly cooling the object, and by controlling the cooling rate of the object to achieve a slow temperature curve that can achieve a degradation heat treatment, the object can be cooled at a relatively uniform temperature without causing a temperature deviation inside the object, thereby causing no residual stress such as thermal stress, and giving toughness to external impact, so that an object with excellent impact resistance can be formed.

[0157] In one embodiment of the present invention, the slow cooling is performed with a slow temperature curve for annealing heat treatment, and for this purpose, the temperature of the inner space of the heating chamber 50 accommodating the workbench S for cooling can be controlled (corresponding to the third temperature T3). In one embodiment of the present invention, a second heat source 55 can be installed in the heating chamber 50, and the molded object can be slowly cooled at a controlled cooling rate by starting the second heat source 55. For example, in one embodiment of the present invention, the first heat source 15 and the second heat source 55 can be started at the same time or almost at the same time, and accordingly, the temperature of the inner space of the heating funnel 10 (corresponding to the second temperature T2) can be heated and maintained at a high temperature of the melting point of the metal block or higher by the first heat source 15, and the liquid metal flow ejected from the heating funnel 10 can be slowly cooled according to the slow temperature curve by the second heat source 55. For example, in various embodiments of the present invention, the first heat source 15 and the second heat source 55 may also be started in a time sequence, but for example, in order not to delay the temperature control of the slow cooling space 50' containing the metal flow of the second material M2 melted by the first heat source 15 (temperature control of the third temperature T3), the first heat source 15 and the second heat source 55 may be started or operated at the same time or almost at the same time, and in order to prevent the rapid cooling of the second material M2 ejected onto the workbench S contained in the slow cooling space 50' and provide a temperature environment suitable for the gasification or volatilization of the matrix of the first material M1, the first heat source 15 and the second heat source 55 may be started at the same time. However, the target set temperatures of the first heat source 15 and the second heat source 55 are different. For example, the first heat source 15 may be controlled to a constant temperature of the second temperature T2 of the melting point of the metal block or higher, while the second heat source 55 may be controlled to a third temperature T3 that changes with a slow temperature curve per unit time to control the cooling speed of the molded object, so that in one embodiment of the present invention, the first heat source 15 and the second heat source 55 may be driven independently of each other.

[0158] The second heat source 55 can be started separately from the first heat source 15 to cool the internal temperature of the heating chamber 50 at a slow cooling rate suitable for the annealing heat treatment. For example, in one embodiment of the present invention, the first heat source 15 and the second heat source 55 can be connected to a separate first switch and a second switch for on-off control, and the first heat source 15 and the second heat source 55 can be controlled by proportional-integral-derivative (PID) with a respective set constant second temperature T2 or a temperature calculated from a set cooling rate (a third temperature T3 that varies with time) as a target temperature value.

[0159] In one embodiment of the present invention, a solid object can be formed by ejecting a second material M2 of a metal flow and slowly cooling the second material M2 accumulated on the workbench S. The first heat source 15 can be started to eject the second material M2 forming the object itself, that is, to melt the metal block as the second material M2, and the second heat source 55 can be started to slowly cool the second material M2 accumulated on the workbench S. In various embodiments of the present invention, the first heat source 15 and the second heat source 55 can be started simultaneously or sequentially. Moreover, after the second material M2 is filled into the filling space FS surrounded by the outline of the object formed by the first material M1 on the workbench S to complete the shape of the object, in other words, after the ejection of the second material M2 from the heating funnel 10 is completed, the activation of the first heat source 15 can be terminated, and thereafter, in order to control the cooling speed of the slow cooling space 50' of the object, the activation of the second heat source 55 can be continued. For example, in one embodiment of the present invention, the first heat source 15 and the second heat source 55 can be started at the same time, or the second heat source 55 can be started continuously when the start-up of the first heat source 15 is stopped. In other words, during the takt-time for completing a modeling object, the start-up time of the first heat source 15 (first start-up time) and the start-up time of the second heat source 55 (second start-up time) can have the following magnitude relationship (first start-up time < second start-up time). For example, the second heat source 55 can be started during the entire takt time of 3D printing, while the first heat source 15 can be started in a shorter time than the entire takt time of 3D printing. For example, in one embodiment of the present invention, the start-up time (second start-up time) of the second heat source 55 includes a slow cooling time for the modeling object to follow a slow temperature curve for slow cooling. Since the slow cooling time is included, which accounts for a considerable proportion of the entire takt time, it can be set to be longer than the start-up time (first start-up time) of the first heat source 15 that does not include the slow cooling time.

[0160] Similar to the first heat source 15, the second heat source 55 can be connected to a second switch to control the third temperature T3 of the internal space of the heating chamber 50, and the activation of the heating line can be turned on and off by the on-off control of the second switch, thereby controlling the third temperature T3 of the internal space of the heating chamber 50. For example, according to the on-off control of the switch, a DC current (constant current) of a constant magnitude can flow through the second heat source, and an intermittent flow of a DC current of a constant magnitude can be formed by the on-off control of the DC current of a constant magnitude.

[0161] In one embodiment of the present invention, the second heat source 55 can provide a favorable environment for heating and maintaining the temperature of the internal space (corresponding to the second temperature T2) of the heating funnel 10 connected to the slow cooling space 50' as one space at the melting point of the metal block or higher by maintaining the third temperature T3 of the slow cooling space 50' of the heating chamber 50 at a temperature higher than room temperature. In this sense, by simultaneously starting the first heat source 15 and the second heat source 55, the power consumption for maintaining the temperature of the space formed in the embedded block 40 and the heating chamber 50 which are fluidically connected to each other at a temperature at least higher than room temperature can be reduced.

[0162] The first nozzle 20a and the second nozzle 10a for spraying the first material M1 and the second material M2 can be located at a height corresponding to the variable height of the workbench S according to the lifting and lowering drive of the workbench S. The first nozzle 20a and the second nozzle 10a are embedded in the embedded block 40 that together forms the slow cooling space 50' for accommodating the workbench S, more specifically, are embedded in the embedded block 40 that defines the upper part of the slow cooling space 50'. According to the relative assembly position between the embedded block 40 and the heating chamber 50, the heating chamber 50 can be used as the reference and fixed at a constant position. In one embodiment of the present invention, the positions of the first nozzle 20a and the second nozzle 10a can be fixed at a constant position based on the heating chamber 50, and according to the lifting drive and two-dimensional translation movement of the connecting rod 100 or the guide block GB connected to the connecting rod 100 (for example, the guide block GB of the third actuator A3 that reflects the lifting movement and translation movement on the two-dimensional plane generated by the first actuator A1 to the third actuator A3) that is powered by the opening 50" passing through the bottom wall 50b of the heating chamber 50, the first nozzle 20a and the second nozzle 10a that maintain a constant position in the heating chamber 50 can be transported to the ejection position P1 and the ejection position P2 of the targeted first material M1 and the second material M2 through the workbench S that is powered by the actuator A through the opening 50" passing through the heating chamber 50.

[0163] In various embodiments of the present invention, the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a can be accumulated at the first ejection position P1 and the second ejection position P2 on the workbench S through the relative transport between the first nozzle 20a and the second nozzle 10a and the workbench S. For example, the first ejection position P1 and the second ejection position P2 where the first material M1 and the second material M2 are accumulated on the workbench S can correspond to the contour position of the modeling object and the filling position of the modeling object itself surrounded by the contour, respectively. In one embodiment of the present invention, the first material M1 and the second material M2 accumulated from the first nozzle 20a and the second nozzle 10a onto the workbench S can have different material phases from the first raw material and the second raw material as raw materials of the first material M1 and the second material M2, respectively, and the first material M1 and the second material M2 can be formed by different pretreatment processes of the first raw material and the second raw material. Such pretreatment processes can be performed by an extrusion device 80 (mixing / extrusion pretreatment) and a heating funnel 10 (heating pretreatment) each including the first nozzle 20a and the second nozzle 10a or connected to the first nozzle 20a and the second nozzle 10a. At this time, in one embodiment of the present invention, considering the connectivity between the first nozzle 20a, the second nozzle 10a and the extrusion device 80 and the heating funnel 10, the positions of the first nozzle 20a and the second nozzle 10a can be fixed, and the workbench S on which the first material M1 and the second material M2 are accumulated from the first nozzle 20a and the second nozzle 10a can be transported. By transporting the workbench S on which the first material M1 and the second material M2 are sprayed from the fixed first nozzle 20a and the second nozzle 10a, the spraying position P1 and the spraying position P2 of the first material M1 and the second material M2 sprayed on the workbench S can be controlled, and a stack of the first material M1 and the second material M2 can be formed at the contour position of the object to be molded and the filling position surrounded by the contour of the object.

[0164] In various embodiments of the present invention, the first nozzle 20a and the second nozzle 10a can be started in a chronological order or simultaneously. For example, in the first nozzle 20a and the second nozzle 10a that are embedded together and fixed in position in the embedding block 40, the outline of the modeling object can be accumulated in advance by starting the first nozzle 20a, and the first nozzle 20a can be stopped and the second nozzle 10a can be started, so that the second material M2 can be subsequently filled into the filling space FS surrounded by the outline of the modeling object of the first material M1 to form the modeling object. For example, in the molding of such an object, the first nozzle 20a and the second nozzle 10a can be started and stopped alternately to form each layer of the object. During the start-up of the first nozzle 20a (during the stop of the second nozzle 10a), the workbench S can be transported based on the cross-sectional data about the contour of the object formed by the first material M1 ejected from the first nozzle 20a, and during the start-up of the second nozzle 10a (during the stop of the first nozzle 20a), the workbench S can be transported based on the cross-sectional data about the object itself formed by the second material M2 ejected from the second nozzle 10a or the filling space FS surrounded by the contour of the first material M1.

[0165] In one embodiment of the present invention, the first nozzle 20a and the second nozzle 10a may be started simultaneously without a time sequence relationship. For example, the first nozzle 20a and the second nozzle 10a may be embedded by an embedding block 40 and bound to each other in a manner of maintaining a constant interval therebetween, and the ejection positions P1 and P2 of the first material M1 and the second material M2 ejected from the first nozzle 20a and the second nozzle 10a may be spaced apart from each other by the interval between the first nozzle 20a and the second nozzle 10a at different positions on the workbench S. For example, the ejection position P1 and the ejection position P2 of the first material M1 and the second material M2 on the workbench S may be formed at an interval equivalent to the interval g between the first nozzle 20a and the second nozzle 10a that are embedded together and bound to each other by the embedding block 40, and the interval g between the ejection position P1 and the ejection position P2 of the first material M1 and the second material M2 on the workbench S may be filled by the metal flow of the second material M2 flowing from the second ejection position P2 of the second material M2 to the first ejection position P1 of the first material M1.

[0166] In one embodiment of the present invention, the gap g between the first nozzle 20a and the second nozzle 10a bound by the embedded block 40 can, for example, be formed to be narrow enough to fill the gap between the ejection position P1 and the ejection position P2 of the first material M1 and the second material M2 corresponding to the gap g between the first nozzle 20a and the second nozzle 10a based on the flow characteristics of the second material M2 such as the fluidity and flow rate of the second material M2.

[0167] In one embodiment of the present invention, the first nozzle 20a and the second nozzle 10a for spraying the first material M1 and the second material M2 having different material phases onto the workbench S can be formed to have different inner diameters according to the different material phases of the first material M1 and the second material M2, and can be sprayed onto the workbench S from the first nozzle 20a and the second nozzle 10a formed to have different inner diameters. In one embodiment of the present invention, the first nozzle 20a can spray the first material M1 in a paste or slurry state, and the second nozzle 10a can spray the second material M2 in a liquid state. At this time, in one embodiment of the present invention, by forming the inner diameter of the first nozzle 20a for ejecting the first material M1 in a paste or slurry state with relatively insufficient fluidity to be larger than the inner diameter of the second nozzle 10a for ejecting the second material M2 in a liquid state with relatively sufficient fluidity, the flow rates of the first material M1 and the second material M2 can be accumulated on the workbench S in a balanced manner. For example, even if the volume of the second material M2 that fills the filling space FS surrounded by the outline of the shape and forms the shape itself is larger than the volume of the first material M1 that forms the outline of the shape, the liquid second material M2 with sufficient fluidity can also accumulate a sufficient volume through the relatively narrow inner diameter of the second nozzle 10a to form the shape itself.

[0168] In one embodiment of the present invention, the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the first material M1 and the second material M2 having different material phases can be controlled in different ways. For example, the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the first material M1 can be controlled according to the rotation speed of the rotating screw 85 driven to rotate inside the delivery pipe 83 of the extruder 80, while the flow rate (volume passing through a cross-sectional area per unit time) or ejection speed of the second material M2 can be controlled according to the internal pressure of the heating funnel 10 filled with the second material M2 or the internal pressure acting on the liquid surface formed in the heating funnel 10 (the pressure of the gas RG filled between the sealing cover 1 covering the feed port and the liquid surface of the second material M2).

[0169] In one embodiment of the present invention, by using liquid metal or metal flow with sufficient fluidity to form a second material M2 for forming an object to be shaped, a shaped object with a smooth and beautiful appearance can be formed, compared with a comparative example of a 3D printing method in which a paste or slurry-like second material M2 including metal powder and a carrier and an adhesive mixed in the metal powder is used to form the object itself.

[0170] In one embodiment of the present invention, the first material M1 and the second material M2 in different material phases are used to have different fluidities to form the outline of the object and the object itself, respectively. For example, in order to limit the flow of the liquid second material M2 when forming the filling space FS filled with the liquid second material M2, the first material M1 forming the outline of the object can have a relatively low fluidity so that it will not collapse under the action of its own weight and has a high shape stability. Unlike the first material M1, the second material M2 can have a relatively high fluidity so as to quickly fill the inside of the outline of the object formed by the first material M1. Thus, in one embodiment of the present invention, since the object is formed by filling the filling space FS surrounded by the outline formed by the first material M1 with a liquid metal flow with sufficient fluidity, all or part of the object can be formed at one time by one filling within the height range in which the cross-sectional data remains the same, and the time required to manufacture the object can be reduced compared with the comparative example, in which the second material M2 in the form of a paste or slurry containing a binder and dispersed with metal powder is dropped onto the workbench S in the form of droplets to form layers of the second material M2 corresponding to the cross-section of the object, the layers of the second material M2 are accumulated to the overall height of the object, and then sintered by laser irradiation to form the object. For example, in the 3D printing of the comparative example described above, since the layers of the second material M2 are accumulated until the overall height of the object by dropping the second material M2 in the form of droplets onto the workbench S, the time required to manufacture the object is relatively delayed compared to the present invention in which the second material M2 in liquid or metal flow is filled into the filling space FS surrounded by the outline of the object made of the first material M1. In particular, since after the height of the object is formed on the workbench S by dropping the second material M2 in the form of droplets, it is also sintered using a separate laser irradiation. Therefore, compared to the present invention in which the object is completed by cooling the second material M2 after filling with the second material M2, not only is a separate laser device required, but there is also a disadvantage of delayed production time.

[0171] In one embodiment of the present invention, as the first material M1 for forming the contour of the sculpted object, even if a paste or slurry-like first material M1 mixed with ceramic particles and a matrix as a carrier for providing fluidity is used, more specifically, compared with applying a liquid metal flow with relatively sufficient fluidity to form the second material M2 of the sculpted object itself, even if the first material M1 in a paste or slurry-like state with relatively poor fluidity to form the contour of the sculpted object is superimposed on the workbench S to form a longer ejection time per unit volume (for example, when comparing the ejection times of the first material M1 and the second material M2 required to form a unit volume of the first material M1 and the second material M2, the ejection time of the first material M1>the ejection time of the second material M2), in one embodiment of the present invention, since the sculpted object is formed by filling the filling space FS surrounded by the sculpted object contour of the first material M1 with the second material M2 that forms the sculpted object itself, the total time required for making the sculpted object may not be changed according to the flow rate. The ejection time of the first material M1 with relatively insufficient fluidity is determined or delayed. Generally speaking, the volume occupied by the shape itself is larger than the volume occupied by the outline of the shape. Accordingly, the limiting factor of the total time required for the production of the shape can be understood as the ejection time of the second material M2 used to form the shape itself surrounded by the outline of the shape, rather than the ejection time of the first material M1 used to form the outline of the shape. Therefore, despite the relationship between the first ejection time and the second ejection time required to form a unit volume of the first material M1 and the second material M2 (first ejection time>second ejection time), the ejection time of the second material M2 occupying a relatively large volume can become a limiting factor in limiting the total time required for the production of the entire shape. In one embodiment of the present invention, by applying a liquid metal flow with relatively sufficient fluidity as the second material M2 that limits the total production time of the shape, the ejection time of the second material M2 can be shortened, thereby shortening the total time required for the production of the shape. Unlike the present invention, in the comparative example, since a paste or slurry material whose fluidity is relatively lower than that of a liquid is used as the material for forming the object itself, the ejection time of the second material M2, which is a limiting factor in the total time required to produce the object, is delayed, and thus the total time required to produce the object may be relatively delayed.

[0172] According to one embodiment of the present invention, the first material M1 can be extruded from the extrusion device 80. According to the rotation of the rotating screw 85 driven to rotate in the conveying pipe 83 of the extrusion device 80, different ceramic particles as the raw material (first raw material) of the first material M1 are respectively put in from the first hopper 81 and the second hopper 82 connected to the conveying pipe 83, and a matrix for giving fluidity to the ceramic particles can form a uniform mixture under the rotation of the rotating screw 85 in the conveying pipe 83, and the conveying speed of the first material M1 can be controlled according to the rotation speed of the rotating screw 85. For example, according to one embodiment of the present invention, the rotation speed of the rotating screw 85 driven to rotate in the conveying pipe 83 of the extruder 80 can be linked with the conveying speed of the first material M1 conveyed along the connecting tube body 70 between the outlet 80a of the extruder 80 and the mating end 20b of the ejection unit 20, and can be linked with the flow rate (flow rate, volume passing through the cross-sectional area per unit time) or ejection speed of the first nozzle 20a at the lower end of the ejection unit 20 formed by the ejection outlet 80a connected at one end of the connecting tube body 70 and the ejection unit 20 connected at the other end of the connecting tube body 70. According to one embodiment of the present invention, when forming a paste or slurry first material M1 mixed with ceramic particles and a matrix, for example, the mixing ratio of the matrix used to give the ceramic particles fluidity can be controlled, and the flow rate (flow rate, volume passing through the cross-sectional area per unit time) or ejection speed of the first material M1 can be controlled by forced extrusion.

[0173] According to one embodiment of the present invention, when forming a paste or slurry first material M1 formed by mixing ceramic particles with a matrix such as a carrier and an adhesive, for example, the first material M1 having relatively high viscosity or viscosity can be formed by adjusting the proportion of the adhesive or the composition of the adhesive for controlling the viscosity or viscosity, and the flow rate (flow rate, the volume passing through the cross-sectional area per unit time) or the ejection speed of the first material M1 can be controlled by forced extrusion. For example, according to one embodiment of the present invention, the height stability of the first material M1 accumulated on the workbench S can be improved by forming the first material M1 having relatively high viscosity or viscosity, and the first material M1 can be extruded onto the workbench S by forced extrusion, so that the flow rate (flow rate, the volume passing through the cross-sectional area per unit time) or the ejection speed of the first material M1 can be controlled independently of the viscosity or viscosity of the first material M1.

[0174] According to one embodiment of the present invention, during the forced extrusion of the first material M1, the flow rate (volume passing through the cross-sectional area per unit time) or ejection speed in the first nozzle 20a connected to the ejection port 80a of the extrusion device 80 can be controlled by increasing or decreasing the rotation speed of the rotating screw 85 driven inside the conveying pipe 83 of the extrusion device 80. In contrast, in the comparative example where a paste or slurry first material M1 is dripped in the form of droplets, when the height stability of the first material M1 accumulated on the workbench S is improved by controlling the proportion or composition of the adhesive included in the first material M1, since the flow rate (flow rate, volume passing through a cross-sectional area per unit time) or the ejection speed of the first material M1 is delayed in conjunction with the viscosity or viscosity of the first material M1, it is necessary to compromise between the height stability of the first material M1 and the flow rate (flow rate, volume passing through a cross-sectional area per unit time) or the ejection speed of the first material M1. For example, unlike one embodiment of the present invention, there may be limitations in improving the flow rate (flow rate, volume passing through a cross-sectional area per unit time) or the ejection speed of the first material M1 to shorten the cycle time while improving the height stability of the first material M1. For example, according to one embodiment of the present invention, by improving the height stability of the first material M1, the liquid metal flow fills the higher filling space FS surrounded by the relatively higher first material M1 contour at one time, thereby shortening the production time of the shaped object. At this time, by shortening the ejection time of the first material M1 itself, for example, by simultaneously increasing the rotation speed of the rotating screw 85 driven in the conveying pipe 83 of the extrusion device 80, the time for forming the first material M1 contour accumulated to a predetermined height is shortened, thereby doubly shortening the cycle time.

[0175] According to one embodiment of the present invention, the first material M1 forms the outline of the modeling object around the filling space FS filled with the liquid second material M2, the second material M2 fills the filling space FS surrounded by the outline of the first material M1, and through subsequent cooling, the modeling object is formed by the second material M2 instead of the first material M1, which may mean that the modeling object is completed by separating the first material M1 after the second material M2 is cooled.

[0176] According to various embodiments of the present invention, the second material M2 formed by the liquid metal flow fills the filling space FS surrounded by the outline of the first material M1, which does not limit the ejection order of the first material M1 and the second material M2. For example, this does not necessarily mean that the filling space FS surrounded by the outline of the first material M1 is filled with the second material M2 only after the outline of the object is formed by ejecting the first material M1. For example, according to various embodiments of the present invention, the ejection of the first material M1 and the second material M2 toward the workbench S providing the support base of the object can be performed simultaneously without any sequential relationship in time. For example, even if the first material M1 and the second material M2 are ejected toward the workbench S at the same time, Due to the difference in fluidity between the first material M1 and the second material M2, the first material M1 will not diffuse or spread widely from the first ejection position P1 of the first material M1 to the plane on the workbench S, but will be limited to the periphery of the first ejection position P1 of the first material M1. Accordingly, the contour of the modeling object formed by the first material M1 can have a high degree of stability and be clearly defined. For example, according to one embodiment of the present invention, the first material M1 is a paste or slurry formed by mixing ceramic particles with a matrix such as a carrier and an adhesive for viscosity control, and has a relatively low fluidity compared to the second material M2. Therefore, the first material M1 can have a high degree of stability based on the low fluidity. For example, according to one embodiment of the present invention, the high stability of the first material M1 can be ensured by controlling the fluidity of the first material M1. While forming a relatively high contour formed by the first material M1, the filling space FS surrounded by the contour of the first material M1 can be quickly filled with the second material M2 formed by the liquid metal flow, thereby shortening the production time of the modeling object by 3D printing according to one embodiment of the present invention. For example, according to one embodiment of the present invention, within the height range where the two-dimensional cross-sectional data of the three-dimensional object is the same, all or part of the object can be formed by ejecting the first material M1 and the second material M2 at one time.

[0177] The 3D printing device according to one embodiment of the present invention may include a control unit (not shown) for acquiring data on the shape of the object and controlling the driving of the workbench S. At this time, the control unit may convey the workbench S for accumulating the first material M1 and the second material M2 at a relatively slow speed within the same height range of the cross-sectional data of the object, so as to start accumulating from a single ejection (single layer) of the first material M1 and the second material M2. For example, in order to accumulate a relatively large volume or a relatively large flow of the first material M1 and the second material M2 at the first ejection position P1 and the second ejection position P2 where the first material M1 and the second material M2 are accumulated to form the height of the object, the workbench S may be conveyed at a relatively slow speed.

[0178] According to one embodiment of the present invention, the first raw material and the second raw material in a different form from the first material M1 and the second material M2 ejected onto the workbench S can be put into the 3D printing device. Since the first material M1 and the second material M2 need to be processed from different first raw materials and the second raw materials through a separate process, considering the connection with the heating funnel 10 and the extrusion device 80 that perform such a pretreatment process, the first ejection position P1 and the second ejection position P2 can be controlled by conveying the workbench S that accommodates the first material M1 and the second material M2 from the first nozzle 20a and the second nozzle 10a while keeping the first nozzle 20a and the second nozzle 10a in a fixed position without conveying the first nozzle 20a and the second nozzle 10a, thereby forming the outline of the modeling object and the shape of the modeling object surrounded by the outline of the modeling object.

[0179] A 3D printing device according to one embodiment of the present invention may include: a first actuator A1, which is used to drive the workbench S to rise and fall along the height direction Z1; and a second actuator A2 and a third actuator A3, which are used to drive the workbench S to translate along a two-dimensional plane in a second direction Z2 and a third direction Z3. These first actuator A1 to third actuator A3 can control the three-axis position of the workbench S independently of each other, for example, can be independently controlled to follow the target position of the workbench S in the first direction Z1 to the third direction Z3. According to one embodiment of the present invention, the second actuator A2 is installed on the guide block GB of the first actuator A1, so that it can also follow the position of the second actuator A2 in the second direction Z2 based on the position of the first actuator A1 in the first direction Z1, and the third actuator A3 is installed on the guide block GB of the second actuator A2, so that it can also follow the position of the third actuator A3 in the third direction Z3 based on the positions of the first actuator A1 and the second actuator A2 in the first direction Z1 and the second direction Z2. As a result, through the connecting rod 100 installed on the guide block GB of the third actuator A3, the workbench S connected to the guide block GB of the third actuator A3 can three-dimensionally follow the position of the first actuator A1 to the third actuator A3 from the first direction Z1 to the third direction Z3 followed by the third actuator A3.

[0180] According to one embodiment of the present invention, the embedded block 40, the heating chamber 50 and the actuator A can be aligned with each other by assembling guide rods R. For example, according to one embodiment of the present invention, the embedded block 40 and the heating chamber 50 can be formed into a substantially hexahedral shape, and the assembling guide rods R can achieve the position alignment between the embedded block 40 and the heating chamber 50 by a group of assembling guide rods R extending across the four corners of the embedded block 40 and the heating chamber 50, for example, the embedded block 40 defining the upper part of the slow cooling space 50' accommodating the workbench S and the four side walls of the heating chamber 50 defining the side of the slow cooling space 50' can be aligned with each other to form a mutually sealed combination. In addition, according to one embodiment of the present invention, the set of assembly guide rods R are aligned with the position of the actuator A disposed outside the heating chamber 50 through the heating chamber 50. Finally, the set of assembly guide rods R can align the actuator A disposed outside the heating chamber 50, the heating chamber 50, the embedded block 40 assembled with the heating chamber 50, and the first nozzle 20a and the second nozzle 10a embedded in the embedded block 40, so that the spraying positions P1 and P2 of the first material M1 and the second material M2 sprayed from the first nozzle 20a and the second nozzle 10a onto the workbench S can be accurately controlled.

[0181] According to one embodiment of the present invention, the shortest dimension of the object to be shaped may be at least 0.05 mm, 0.1 mm, 0.2 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm or any dimension therebetween. According to one embodiment of the present invention, the longest dimension of the object to be shaped may not exceed 100 mm, 50 mm, 10 mm, 5 m, 1000 mm, 900 mm, 800 mm, 700 mm, 600 mm, 500 mm, 400 mm, 300 mm, 250 mm or any dimension therebetween. According to one embodiment of the present invention, the object to be shaped may correspond to a functional object, for example, a medical device or a plastic surgery device or a part of a plastic surgery device, or according to various embodiments of the present invention, the object to be shaped may correspond to a decorative object.

[0182] In one embodiment of the present invention, the 3D printing device may include:

[0183] A workbench, which is used to provide a support base for the object to be shaped;

[0184] A first nozzle and a second nozzle are arranged on the workbench, the first nozzle is used to spray out a first material in a paste or slurry state to form the outline of the object to be shaped, and the second nozzle is used to spray out a second material in a liquid state to fill a filling space surrounded by the first material;

[0185] An extrusion device connected to the first nozzle and extruding a first material in a paste or slurry state toward the first nozzle, wherein the first material includes ceramic particles and a matrix in which the ceramic particles are dispersed;

[0186] a heating funnel connected to the second nozzle and used to take the metal block as input, melt the metal block to supply molten metal, that is, the second material in a liquid state; and

[0187] The heating chamber is used to accommodate the workbench and provide a slow cooling space for the molded object formed by the first material and the second material accumulated on the workbench.

[0188] A 3D printing method according to an embodiment of the present invention may include:

[0189] Extruding a first material in a paste or slurry state from an extrusion device to a first nozzle, wherein the first material comprises ceramic particles and a matrix in which the ceramic particles are dispersed;

[0190] Spraying a first material forming a contour of a modeling object to be modeled through a first nozzle;

[0191] Containing the metal block through a heated funnel;

[0192] melting the metal block and forming a flow of the molten metal block so that a second material of the molten metal is directed toward a second nozzle;

[0193] Spraying the second material through the second nozzle to fill the filling space surrounded by the outline of the modeling object formed by the first material with the second material; and

[0194] The first material and the second material are repeatedly sprayed out layer by layer to form a modeling object on the workbench.

[0195] The present invention has been described with reference to the embodiments shown in the accompanying drawings, but these embodiments are merely exemplary, and a person skilled in the art to which the present invention pertains will appreciate that the present invention is susceptible to various modifications and other equivalent embodiments.

[0196] Industrial Applicability

[0197] The present invention can be applied to a 3D printing device, which is used to form a modeling object with a specific shape.

Claims

1. A 3D printing device, comprising: A workbench, which is used to provide a support base for the object to be shaped; A first nozzle and a second nozzle are arranged on the workbench, the first nozzle is used to spray out a first material in a paste or slurry state to form the outline of the object, and the second nozzle is used to spray out a second material in a liquid state to fill a filling space surrounded by the outline of the object formed by the first material; an extrusion device connected to the first nozzle and used for extruding the first material toward the first nozzle so as to eject the first material in a paste or slurry state formed by mixing ceramic particles and a matrix in which the ceramic particles are dispersed; a heating funnel connected to the second nozzle and used to take a metal block as an input and melt the metal block so as to eject the second material in the form of a liquid metal flow formed by melting the metal block through the second nozzle; as well as A heating chamber accommodates the workbench and provides a slow cooling space for the first material and the second material accumulated on the workbench from the first nozzle and the second nozzle.

2. The 3D printing device according to claim 1, characterized in that: The inner diameter of the second nozzle is smaller than the longest dimension of the metal block introduced from the feed port at the upper end of the heating funnel connected to the lower end of the second nozzle.

3. The 3D printing device according to claim 1, characterized in that: A first heat source is wound along the outer peripheral surface of the heating funnel, and the first heat source is used to melt the metal block put into the heating funnel.

4. The 3D printing device according to claim 3, characterized in that: The first heat source is disposed between the heating funnel and the ejection unit. A second nozzle is formed at a lower end of the heating funnel opposite to the workbench. A first nozzle is formed at a lower end of the ejection unit opposite to the workbench.

5. The 3D printing device according to claim 1, characterized in that: Also includes: An embedding block is used to embed the first nozzle and the second nozzle together.

6. The 3D printing device according to claim 1, characterized in that: The third temperature of the slow cooling space of the heating chamber, the second temperature of the heating funnel having a second nozzle formed at the lower end opposite to the workbench, and the first temperature of the ejection unit having a first nozzle formed at the lower end opposite to the workbench satisfy the relationship of second temperature > third temperature > first temperature.

7. The 3D printing device according to claim 1, characterized in that: Also includes: A first heat source, which is wound along the outer peripheral surface of the heating funnel and is used to melt the metal block put into the heating funnel; as well as A second heat source is formed in the heating chamber and is used to control a cooling rate of the first material and the second material accumulated on the worktable from the first nozzle and the second nozzle.

8. The 3D printing device according to claim 7, characterized in that: During the cycle time for forming a shape, A first startup time from the start of startup to the end of startup of the first heat source and a second startup time from the start of startup to the end of startup of the second heat source have a magnitude relationship of first startup time<second startup time.

9. The 3D printing device according to claim 1, characterized in that: The flow rate of the first material ejected from the first nozzle to the worktable is controlled by the rotation speed of the rotating screw driven inside the delivery pipe of the extruder, The flow rate of the second material sprayed from the second nozzle to the worktable is controlled by the pressure of the gas above the liquid surface of the second material filling the metal flow inside the heating funnel.

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