KR20160017799A - 3D printer head assembly with a electrode grid and a system therewith and a 3D manufacturing method using it - Google Patents

Abstract

The present invention relates to a 3D printer which enables plane-printing using an electrode grid to improve printing speed, increases vertical and horizontal resolution of 3D printing, and simplifies a post-treatment process. Provided is a head assembly of a 3D printer, which includes: a printing material container (11) for supplying a printing material particle electrically charged with a predetermined charge to an electrode grid (12); the electrode grid (12) including a plurality of electrode cells (121) arranged in a predetermined pattern; a first electrically charging device (13) for applying a predetermined voltage to each of operation electrode cells (122) which the printing material particle is attached to or detached from; and a transfer module (14) having the electrode grid (12), the printing material container (11) and the printing stage (21) relatively move, for formation of a first relative position between the electrode grid (12) and the printing material container (11) in order for the electrode grid (12) to receive the printing material particle from the printing material container (11), and a second relative position between the electrode grid (12) and the printing stage (21) in order for the electrode grid (12) to mount the printing material particle on the printing stage (21), wherein the attachment and detachment of the printing material particle to or from the operation electrode cells (122) are based on electrical attraction and repulsion between the operation electrode cells (122) and the printing material particle generated by a predetermined voltage applied from the first electrically charging device (13). Also, provided is a 3D printer.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head assembly for a stereolithography apparatus using an electrode grid, a stereolithography apparatus using the same and a stereolithography method using the electrode assembly,

The present invention relates to a 3D forming apparatus, and more particularly, it relates to a 3D forming apparatus capable of surface-forming using an electrode grid, thereby increasing a molding speed, increasing vertical and horizontal resolution of a stereolithography, A head assembly and a stereolithography apparatus of a 3D stereolithography apparatus, and a stereolithography method using the same.

3D printing is one of the methods of manufacturing products. Since it uses a lamination method, the loss of material is smaller than that of conventional cutting, and relatively low manufacturing cost is required. In recent years, technology in this field has been recognized as a next generation production technology beyond prototype production. It is possible to increase the speed of production, increase the completeness of output (resolution), diversify usable materials, This is because accessibility has improved.

There are various schemes of 3D printing such as SLA (Stereo Lithography Apparatus), SLS (Selective Laser Sintering) and FDM (Fused Deposition Modeling).

In US Patent No. 7074029 entitled " Accumulation, control and accounting of fluid by-product from a solid deposition modeling process " (hereafter referred to as prior art 1), at least one molding material container carrying a molding material, Means for separating the molding material from the molding material container by an intermittent amount, means for moving the separated molding material to the dispenser, dispenser for dispensing the molding material layerwise onto the platform for molding, And a means for feeding the shaped material.

US 7074029 B2

Conventional technique 1 is based on line-shaping in which a molding material is scanned by a complicated path using a light source such as a laser, and then hardened or sintered after a shaping preparation step such as a planarization by adopting a stereolithography method of a typical SLS system , There is a problem that the molding time is prolonged. In addition, post-processing such as removal of the uncured part of the SLS-based stereolithography method is inevitable, which increases the total number of process steps and increases the total molding time.

In order to solve the above problems, the present invention provides a molding material container 11 for supplying molding material particles charged with a predetermined electric charge to an electrode grid 12, a plurality of electrode cells 121 arranged in a predetermined pattern A first charging device 13 for applying a predetermined voltage to each of the working electrode cells 122 to which the shaping material particles are adhered or desorbed and the electrode grid 12 to be connected to the molding material container 11 A first relative position between the electrode grid 12 and the molding material container 11 for receiving the molding material particles from the molding grid 21 and an electrode grid 12 for seating the molding material particles on the molding stage 21 And a transfer module 14 functioning to relatively move the electrode grid 12, the molding material container 11 and the molding stage 21 relative to each other to form a second relative position between the molding stage 21 and the molding stage 21, And for working electrode cell 122, The attachment and detachment of the type material particles depend on the electrical attraction and repulsion between the working electrode cell 122 and the molding material particles generated by the predetermined voltage applied from the first charging device 13. [ A head assembly for a device is provided.

Further, there is provided a stereolithography apparatus including a head assembly, a light source module 30, a molding stage module, and a control module 40 of the stereolithography apparatus.

Further, a method of molding a three-dimensional molding using the stereolithography apparatus is provided.

The first effect of the present invention is that the molding speed can be increased by using the molding method based on the surface-molding method. By selecting only the portion to be formed using the electrode grid 12, The third effect is that by using the electrode grid 12 that is finely manufactured, not only the horizontal resolution but also the vertical resolution can be increased. In addition, there is an additional advantage that it is advantageous for large area molding.

According to the first effect of the present invention, the materials constituting one forming layer are prepared at one time at the plane level, and the process of sintering and curing the same is performed all at once on a plane basis using a line laser, So that the entire molding time can be shortened considerably.

With regard to the second effect, according to the present invention, only the portion constituting the molding is selected and brought in each molding layer, and the molding layer is formed by sintering and melting the molding layer, unlike the conventional SLS or SLA stereolithography It is possible to shorten the process steps and shorten the total molding time by omitting the procedures such as the additional removal of uncured portions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing one embodiment of a head assembly of a stereolithography apparatus and a stereolithography apparatus of the present invention. FIG.
2 is an explanatory view for explaining an electrical mechanism of a stereolithography apparatus of the present invention;
3 is an explanatory view showing one embodiment of the shape of the particle attachment portion of the electrode grid 12 of the present invention and the arrangement pattern of the electrode cells 121 of the electrode grid 12. Fig.
4 is an explanatory view showing an embodiment of an electrode grid having a planar electrode cell of the present invention further including a septum grid.
5 is an explanatory view showing one embodiment of a three-dimensional electrode cell of the electrode grid 12 of the present invention.
6 is a block diagram showing the function of the control module 40 of the stereolithography device of the present invention.
Fig. 7 is an explanatory view showing an embodiment of the conveyance module 14 of the stereolithography apparatus of the present invention. Fig.
8 is an explanatory view showing an embodiment of a rotary transfer plate 141 of a stereolithography apparatus according to the present invention.

First, the meaning of terms used in the description of the present invention will be described. The shaping layer is an element that is laminated to form a stereolithography. The electrode cell 121 is a subcomponent forming the electrode grid 12. In the electrode cell 121, a voltage is applied to form a shaping layer so that shaping material particles are adhered to or detached from the surface of the electrode cell 121.

The head assembly of the stereolithography apparatus of the present invention has the purpose of forming molding layers for molding a three-dimensional molding, and more particularly, it relates to a head assembly for shifting and moving molding material particles supplied to form a molding layer, 21). A molding material container 11 for supplying molding material particles charged with a predetermined electric charge to an electrode grid 12 and an electrode grid 12 having a plurality of electrode cells 121 arranged in a predetermined pattern A first charging device 13 for applying a predetermined voltage to each of the working electrode cells 122 to which shaping material particles are adhered or desorbed and an electrode grid 12, a molding material container 11, and a molding stage 21 ) Relative to each other as a main component.

From the viewpoint of the shaping material particles, the shaping material particles charged with a predetermined charge are approached by the electrode grid 12 which is moved by the transporting module 14 while being loaded on the molding material container 11, When a voltage of polarity opposite to the charge polarity of the molding material particles is applied to the working electrode cell 122 of the electrode cell 121 constituting the electrode grid 12, do. Thereafter, the electrode grid 12, the molding material container 11 and the molding stage 21 move relative to each other by the transfer module 14, which causes the molding material particles to move from the inside of the molding material container 11 to the molding stage 21) causes spatial movement in the upward direction. Next, when a voltage having the same polarity as the charge polarity of the molding material particles is applied to the working electrode cell 122, the molding material particles are detached from the working electrode cell 122 by an electrical repulsive force, Or on the previous shaping layer.

The electrical mechanism used in the present invention will be described. First, the shaping material particles are supplied to the electrode grid 12 in a charged state with a predetermined charge. The polarity of such charge is positive or negative regardless of whether the charge amount per particle is different depending on the type of molding material used something to do. In addition, an electric field is not formed in the electrode cell-unactuated electrode cell 122 in which no voltage is applied among a plurality of electrode cells 121 forming the electrode grid 12, so that the molding material particles do not adhere thereto And from the viewpoint of the shaping layer configuration, this portion becomes a blank portion. When a voltage opposite in polarity to the negative polarity of the molding material particles is applied to the working electrode cell 122, an electrical attractive force acts between the working electrode cell 122 and the molding material particles, and this attracting force is applied until the applied voltage is released The shaping material particles remain attached to the particle attachment surface 123 of the working electrode cell 122 while the pressing is performed. Then, when a voltage having the same charge polarity as that of the molding material particles is applied to the working electrode cell 122, an electrical repulsive force acts between the working electrode cell 122 and the molding material particles, And acts as a cause of desorption from the particle attachment surface 123 of the cell 122. The voltage magnitude (absolute value) applied to the working electrode cell 122 is such that the shaping material particles attached to the particle attachment surface 123 of the working electrode cell 122 are subjected to vibrations So as to form an electrical attractive force so as to maintain a firm attachment without being desorbed from the particle attachment surface 123. However, it should be taken into account that an arc is generated at the corner of the working electrode cell 122, which may cause damage when forming the forming layer and may cause electric problems in the apparatus. Further, when the voltage applied to the working electrode cell is increased, it is possible to utilize that more molding material particles are moved by the electric field and transition to the surface (particle attachment surface) of the working electrode cell, it means. It should be noted, however, that the formation of a shaping layer by supporting such a large number of molding material particles lowers the vertical resolution of the three-dimensional object.

However, if the voltage is too large, the time required for detaching and attaching the particles to the electrode cell by using the electrical attractive force or the repulsive force is only a few milliseconds from the point of voltage application. An illustrative view of the present invention utilizing such an electrical mechanism is shown in Fig.

The molding material may be a polymer resin or a powder of a ceramic or a metal, and the crystal may be used as a light source for melting or sintering, particularly a laser- Shall be made in relation to the wavelength band of In addition, by using the shaping material particles charged with a predetermined charge, electrostatic force can be utilized for attaching / detaching shaping material particles to the working electrode cell 122 as described later.

Hereinafter, the head assembly of the stereolithography apparatus according to the present invention will be described in detail on a component basis.

The shaping material container 11 has a first function of supplying shaping material particles from the outside and storing them, a first function of forming electrode materials in the form of shaping material particles (hereinafter referred to as " shaping material particles " A second function of providing an external exposed surface, and a third function of enhancing the reliability of attachment of the molding material particles by planarizing the formed external interface surface. Particularly, in relation to the third function, after the electrode grid 12 adheres to the particle attaching surface 123 and moves the molding material particles, the externally exposed surface of the molding material particle has a concave-convex structure locally, However, since the molding material particles have a relatively low fluidity, the non-planar uneven structure may be increased as the number of times that the electrode grid 12 receives supply of the molding material particles increases. In this way, some of the working electrode cells 122 may be placed outside the critical distance to act on the nearest forming material particles for electrical attraction for attachment, which may degrade molding reliability. This problem can be solved by setting the voltage magnitude to be applied to the working electrode cell 122 to be large and increasing the range of electric attraction force, but it is also possible to selectively include a separate shaping material surface planarizing portion in the molding material container 11, Can respond. This shaping material surface planarizing section is constituted by a vibrating means of various constitutions functioning to indirectly planarize the exposed surface of the molding material by pulsating vibration of the molding material container 11 itself and a separate vibrating means for directly leveling the exposed surface of the molding material A roller or a blade, or an agitator functioning to flatten the exterior surface of the molding material indirectly by stirring the molding material under the molding material layer, or the like.

The shape of the molding material container 11 can be varied as long as it can perform the function of loading the molding material particles and providing an external exposed surface to which the electrode grid 12 can approach and be supplied with the molding material particles Can be set. 1, the molding material container 11 is mounted in a shape of a tray that is opened on the upper surface side so that the molding material particles are loaded at a constant height and the electrode grid 12 can be input / .

In supplying shaping material particles charged with a predetermined electric charge to the molding material container 11, it is also possible to supply the preformed charged particles from the outside or to supply the chargeable particles to the molding material container 11 And the second charging device provided in addition to the first charging device. Such a second charging device should have a charging function corresponding to whether the particles used are polymer resin, metal, or ceramic, and various known methods such as corona charger and the like may be used.

The electrode grid 12 performs a first function of receiving and receiving the molding material particles from the molding material container 11 and a second function of placing the supplied molding material particles on the molding stage 21. As described above, the electrical attraction or the repulsive force acting between the molding material particles and the working electrode cell 122 to perform the first function and the second function is used. The electrode grid 12 is basically formed so as to have a plurality of electrode cells adapted to apply voltage to each of them independently.

The electrode grid 12 should have a platform for collecting the electrode cells 121 as described later. In particular, when the electrode cell 121 is manufactured by a semiconductor process, the platform becomes a substrate. On the platform, the electrode cells 121 must be arranged in a predetermined pattern. As an example of such a pattern, if a matrix pattern having a predetermined number of rows and a predetermined number of rows is adopted, So that it is possible to achieve a single plane, and the control of each electrode cell 121 is facilitated. In the arrangement of the electrode cells 121, the size of the gap between the electrode cell 121 and the adjacent cell must be carefully determined. If the size of the gap is too large, When the electrode cell 121 is formed into a three-dimensional shape, it is necessary to treat the electrode cell 121 so that the molding material particles do not intrude into the gap. Conversely, if the size of the gap is too small, the electrode cell 121 and the electrode cell 121 are electrically connected to each other and short-circuited, so that individual control of the electrode cell 121 becomes impossible, It should be taken into account that fabrication costs can be increased.

The electrode cell 121 must have a particle attachment surface 123 on which the shaping material particles are adhered or desorbed. The shape of the particle attachment surface 123 is such that when the individual electrode cells 121 are arranged, Of the plane. However, considering that there is a phenomenon that the shaping material particles are slightly spread out in a plane in the process of melting or sintering at the time of forming the shaping layer, the shape of the electrode cell 121 may be allowed to have a circular shape. Furthermore, considering that the quality of the molding can be improved by setting the resolution in the horizontal and vertical directions to be the same in the molding plane, it is preferable to set the shape of the particle attachment surface 123 to be a square, a regular hexagon, or a circle Do. Since the size of the particle attachment surface 123 is the size of the electrode cell 121 and is directly connected to the horizontal resolution of the stereolithography, it is necessary to downsize the particle attachment surface 123, and ultimately, So that one of the molding material particles is adhered to and detached from one of the molding materials 121. An embodiment of the arrangement pattern of the electrode cell 121 and the electrode grid 12 is shown in Fig.

The electrode cell 121 having the above-described particle attachment surface 123 may be flat or three-dimensional in its shape. The planar electrode cell 121 is an electrode cell focusing platform-for example, only the particle attachment surface 123 is exposed in a form embedded in a substrate, so that the electrode cell 121 is formed into a kind of flat pad shape . One embodiment of such a planar electrode cell is shown in Fig.

The electrode grid having the flat pad-shaped electrode cells may further include a septum grid formed of non-conductive partition walls surrounding the respective electrode cells of the flat pad shape. One embodiment of such a configuration is shown in Fig. 4 (a) shows that a diaphragm grid is mounted on an electrode grid made of electrode cells having a flat pad shape, and Fig. 4 (b) shows the shape of the electrode grid on which the diaphragm grid thus manufactured is mounted. In the case of the shape of the electrode cell as in the embodiment shown in FIG. 3 (b), a septum grid having a shape as shown in FIG. 4 (c) may be adopted. When a voltage is applied to the working electrode cell, the shaping material particles are adhered to fill part or all of the space formed by the partition wall and the electrode pad-shaped electrode cell. As the voltage applied to the working electrode cell increases, more shaping material particles are moved by the generated electric field and transition to the surface (particle attachment surface) of the working electrode cell. The higher the height of the partition wall, the greater the number of the molding material particles can be carried. However, it should be taken into account that the formation of the molding layer by carrying many molding material particles lowers the vertical resolution of the three-dimensional object. In addition, it is also possible to fill only a part of the formed partition wall without filling the whole of the partition wall. In other words, the configuration in which such a septum grid is included in the electrode grid has the advantage that the deposition amount of the molding material particles can be more easily quantitatively controlled. Furthermore, the bulkhead grid must be formed of nonconductive material since only the interior thereof needs to be filled with the molding material particles.

On the other hand, the three-dimensional shape of the electrode cell 121 means that the particle attachment surface 123 protrudes from the platform so that the overall shape of the electrode cell 121 becomes a square pillar, a hexagonal pillar, and a cylinder. However, even in the case of such a three-dimensional electrode cell 121, since the fact that the molding material particles actually adhere is limited to the outermost particle attachment surface 123, there is no difference in function between the planar electrode and the three-dimensional electrode cell 121 can do. In the case of the three-dimensionally shaped electrode cell 121, the molding material particles may penetrate into the gap between the electrode cell 121 and the electrode cell 121. To prevent this, a non-conductive polymer or the like is applied to the gap To remove the gap or to form the gap smaller than the diameter of the molding material particles. One embodiment of the three-dimensional electrode is shown in Fig. 5, wherein the particle attachment surface 123 has a square shape, and the overall shape of the three-dimensional electrode is quadrangular.

Furthermore, concave depressions 123a may be formed at the tip of the three-dimensional electrode cell 121 so that the molding material particles can be embedded. In this case, a greater amount of molding material particles than the front end portion is attached to the front end portion, which means that the shortage of the molding material particles due to the existence of the gap between the electrode cells 121 may be compensated. An example of such a depression 123a of the tip portion is shown in Fig. 5 (b).

The electrode cell 121 can be formed by a conventional method of forming an electrode pad for a circuit on the above-described electrode-cell focusing platform-substrate, and a wiring pattern for applying a voltage to each electrode cell 121 To the platform. However, when the wiring pattern is formed on the surface on which the particle mounting surface 123 is formed, the proportion of the particle mounting surface 123 in the total area may decrease, so that the wiring pattern is preferably formed on the inside and the back surface of the substrate Do. As an example of manufacturing the three-dimensional electrode cell 121, there can be considered a method in which a metal is printed on an array pattern on a substrate surface, and then the metal is seeded and electroplated to grow .

The electrode cell 121 is made of a conductive member and has a good resistance to voltage, durability and durability in view of the use environment in which the voltage is constantly applied / released to the electrode cell 121 and attached / Surface strength and the like. Particularly, it is more preferable to use stainless steel (SUS) or invar steel.

The first charging device 13 has a function of applying or releasing a predetermined voltage to the working electrode cell 122 and can be constituted by a known charging device such as a corona type charger. The first charging device 13 must have an interface capable of precisely pressurizing each electrode cell 121 constituting the electrode grid 12. This interface is electrically connected to all of the wiring patterns of the electrode grid 12, and has a first function capable of selectively depressing and releasing only a specific working electrode cell 122 and a first function of attaching molding material particles to the working electrode cell 122 And a switching function (a second function) for switching between the voltage for the first voltage and the voltage for the second voltage.

The transfer module 14 functions to relatively move the electrode grid 12, the molding material container 11 and the molding stage 21 relative to each other. A first relative position between the electrode grid 12 and the molding material container 11 for receiving the molding material particles from the molding material container 11 from the electrode grid 12 and a first relative position between the electrode grid 12 and the molding stage 21 In order to repeatedly form a second relative position between the electrode grid 12 and the shaping stage 21 for seating the shaping material particles wherein the electrode grid 12 is placed in the shaping material container 11 When the predetermined voltage is applied to the working electrode cell 122 by the first charging device 13, the shaping material particles are effectively applied to the working electrode cell 122, Quot; means the mutual position between the electrode grid 12 and the molding material container 11 that can be attached to the mold 122. In determining the first relative position, the distance between the electrode grid 12 and the molding material particle surface loaded in the molding material container 11 should be determined by the magnitude of the electrical attraction generated in the electrode grid 12. That is, this optimum distance should be set to be smaller than the maximum distance that the generated electric field can have on the molding material particles. It is also possible to consider that the distance between the electrode cells and the surface of the molding material particles is made close to zero by setting the distance to zero. The second relative position is a state in which the electrode grid 12 is positioned in parallel to the upper surface of the molding stage 21 or the shaping layer surface already formed in the molding stage 21 at an appropriate distance, The shaping material particles are desorbed to be effective on the upper surface of the above-described shaping stage 21 or at a predetermined position of the immediately preceding shaping layer surface formed on the shaping stage 21 by a predetermined voltage And the position between the electrode grid 12 and the shaping stage 21 that can be accurately seated. In the determination of the second relative position, the distance between the electrode grid 12 and the shaping stage 21 or the surface of the immediately preceding shaping layer should be determined by the magnitude of the electrical repulsion generated in the electrode grid 12. It is also possible to consider that the distance between the electrode cell and the shaping stage 21 or the surface of the immediately preceding fabricated layer is made to be close to zero. In short, the first relative position and the second relative position are arranged in both the horizontal and vertical directions to attach the molding material particles to the electrode grid 12 and to place the molding material particles in the correct position on the molding stage 21 Location.

First, the electrode grid 12 can be relatively moved with respect to the molding material container 11 and the molding stage 21, and this can be performed by the molding material container 11 And the external shaping stage 21 are fixed on the absolute coordinate system, and the electrode grid 12 is moved to repeatedly form the first relative position and the second relative position (electrode grid transfer formula). The transfer module 14 firstly causes the electrode grid 12 to enter downward from the top of the molding material container 11 so that the surface of the molding material particles loaded on the molding material container 11 and the predetermined (The implementation of the first relative position). The distance may be such that the electrical attraction generated in the working electrode cell 122 can reach the molding material particles. After attaching the shaping material particles, the electrode grid 12 is moved in space and transferred to a predetermined position of the shaping stage 21 (the implementation of the second relative position), so that the shaping material particles are placed at predetermined positions of the immediately preceding shaping layer More precise alignment requires more accurate alignment in the implementation of the first relative position. Second, the molding material container 11 and the molding stage 21 can be moved relative to the electrode grid 12, which fixes the electrode grid 12 on the absolute coordinate system, And the shaping stage 21 is moved to repeatedly form the first relative position and the second relative position (the molding material container 11 and the molding stage transfer formula). The transfer module 14 first causes the shaping material container 11 to enter upward from the bottom of the electrode grid 12 so that the surface of the molding material particles loaded on the shaping material container 11 and the surface of the electrode The shaping material container 11 is positioned so that the grid 12 is parallel to a predetermined distance (implementation of the first relative position). After attaching the molding material particles, the molding material container 11 is moved to the designated place. Thereafter, the molding stage 21 is moved in space and transferred to a predetermined relative position with respect to the electrode grid 12 (implementation of the second relative position), unlike in the implementation of the first relative position, It is the same as in the case of the electrode grid transfer type transfer module 14 described above that more accurate alignment is required in order to accurately mount the substrate in a predetermined position of the layer. Third, a combination of the above-described methods can be considered. In other words, for example, the horizontal movement to implement the first relative position and the second relative position is performed by moving the molding material container 11 and the molding stage 21, and the movement in the vertical direction is performed by the electrode grid 12 ) Can be moved. As another embodiment, a hybrid method of adopting the electrode grid transfer formula for implementing the first relative position and adopting the shaping stage transfer formula for realizing the second relative position may be applied. The above-mentioned three implementations are preferred embodiments of the transport module 14 implementation, but are not limited thereto. In the concrete implementation of the conveying module 14, it is preferable to implement a three-axis conveying device capable of three-axis position control so as to enable precise three-dimensional movement and alignment, but the present invention is not limited thereto. It is essential to implement the feed module 14 by applying a high-performance servomotor and a high-precision feed gear to each of the three axes to precisely follow the drive signal.

Next, the stereolithography apparatus of the present invention will be described. One embodiment of a stereolithography apparatus is shown in FIG. The stereolithography apparatus includes a molding stage module 20 and a light source module 30 and a control module 40 in the head assembly of the stereolithography apparatus.

The shaping stage module 20 includes a shaping stage 21 that is attached to the working electrode cell 122 and is placed on the upper surface of the shaping material particle after the shaping material particle is detached from the working electrode cell 122 . The molding stage 21 is an element in which a stereoscopic molding starts to be molded thereon, and a stereoscopic molding is stuck on the molding stage and after the molding is finished. Thus, the upper surface of the molding stage 21 should be treated with a material capable of maintaining a certain degree of adhesion before and after the molding material placed thereon is melted or sintered by molding light. Further, it should be noted that the quality of the stereoscopic molding is ensured without separating the molding from the molding stage 21 despite the vibration and shock generated when the molding stage 21 moves during the molding process. The shaping stage 21 may be formed with a coupling structure capable of coupling the conveying module 14 described above. In this case, the transfer module 14 can move the molding stage 21 to form the second relative position described above. Alternatively, the shaping stage module 20 may include a separate shaping stage driving section for driving the shaping stage 21. The shaping stage driving unit is constituted by elements capable of transmitting the power to the shaping stage 21 because the shaping stage 21 has a function of allowing the shaping stage 21 to move up and down as the stacking progresses. An external power source such as a servo motor and a bar-type power transmission member causing up and down displacement of the molding stage 21 can be applied. However, the present invention is not limited to this embodiment, Mechanical configuration can be considered. However, when a high-resolution molding operation is scheduled, for example, the thickness of one molding layer is set to several tens to several hundreds of micrometers, the scale of the upper and lower displacements of the molding stage 21 must also be determined in such a range. The precision of the element should also be chosen to be high.

The light source module 30 functions to mold the molding layer by melting or sintering the molding material particles seated on the molding stage 21, and the molding layers are laminated, resulting in the molding of the resulting stereoscopic molding. The light source to be used should be selected according to the molding material. The light source may be an LED, which can irradiate light of a wavelength range capable of melting or sintering them depending on whether the molding material is a polymer resin particle, a ceramic or a metal particle. Or bulb. However, the energy density of the laser should be carefully controlled so that the shaping beam does not affect the already formed finished layer of the sintered lower layer. Further, in consideration of the fact that the particle shaping apparatus of the present invention enables the surface shaping in the shape of the shaping light beam, the shaping light beam is converted into a line laser so as to cause melting or sintering at the surface dimension ), It is preferable from the viewpoint that the molding speed can be increased. The line laser can be implemented by mounting a special lens on the front surface of a general laser emitting portion.

The control module 40 interlocks and controls each component of the stereolithography device and determines which electrode cell 121 is to be used as the working electrode cell 122 based on the shape information of the input shaping layer, Vibrating operation or stopping of the molding material container 11, operation of the conveying module 14, on / off of the light source module 30, operation of the shaping stage 13, It is needless to say that each of these functions must be performed in conjunction with each other based on the shaping layer forming cycle. A specific implementation of such a control module 40 may be performed by a circuit or a combination of software and circuitry.

The stereolithography apparatus of the present invention may have two or more electrode grids 12. For example, when two electrode grids 12 are provided, while one electrode grid 12 is supplied with shaping material particles at the above-described first relative position, another electrode grid 12 is positioned at the above- The shaping material particles can be placed on the shaping stage 21 in the next cycle and the two electrode grids 12 can perform their functions in the next cycle. The idle molding time can be minimized, and the total molding time can be shortened.

The transfer module 14 of the stereolithography apparatus can be configured to include a rotation transfer plate 141. The rotation transfer plate 141 has a molding material container 11 and a molding stage 21 on the upper surface thereof The first function is to perform the second function of transporting the molding material container 11 and the molding stage module 20 so as to be aligned below the electrode grid 12 while being rotated by the rotation transfer plate driving part 142. 7, the shaping stage 21 and the molding material container 11 are mounted on the upper surface of the disk-shaped rotary transfer plate 141 at positions facing each other, The molding material container 11 and the molding stage 21 are repeatedly positioned below the rotary transfer plate 141 by rotating the rotary die plate driving part 142 by 180 degrees. However, the first mutual position and the second mutual position are not formed only by the fact that the rotary grid 81 is located below the rotary table 81, and the electrode grid 12 is moved upward and downward, So that it has a proper clearance with the molding stage 21. In this embodiment, the up and down movement is performed by the electrode grid transfer section 143, in other words, the transfer module 14 in the embodiment of FIG. 7 includes the rotary transfer plate 141, the rotary transfer plate driver 142 And an electrode grid transfer unit 143.

It is also conceivable to form the molding material container 11 and the molding stage 21 directly on the upper surface of the rotary transfer plate 141, as in the case of the present invention shown in Fig. 8, The upper surface of the rotary transfer plate 141 is used as the molding stage 21 or the upper surface of the rotary transfer plate 141 is engraved to form the molding material container 11. A concrete molding method using this will be described later. In this embodiment, the molding material container may have a depth equal to the diameter of the molding material particles. In this case, the molding material particles to be filled may form a so-called mono layer, The maximum stereoscopic resolution can be realized.

Next, a method of forming a three-dimensional object using the stereolithography apparatus of the present invention will be described. First, the transport module 14 transports the electrode grid 12 and the molding material container 11 to have a first relative position with respect to each other. At this time, no voltage may be applied to the electrode grid 12. This situation is shown in Fig. 2 (a). Second, a predetermined voltage is applied to at least one working electrode cell 122 selected by the control module 40 to attach the shaping material particles to the working electrode cell 122. The predetermined voltage at this time should be a voltage of a polarity opposite to the charge polarity of the molding material particle. This situation is shown in Fig. 2 (b). In this embodiment, negative voltage is applied by the first charging device in order to use positively charged molding material particles. Third, the transfer module 14 transfers the electrode grid 12 and the molding stage 21 to have a second relative position with respect to each other. During the transfer, the voltage in the second step should be maintained while the attached molding material particles are not desorbed. This situation is shown in Fig. 2 (c). Fourth, a predetermined voltage is applied to the working electrode cell 122 so that the shaping material particles desorbed from the working electrode cell 122 are placed on the shaping stage 21 or the surface of the immediately preceding shaping layer. The voltage at this time should be the same polarity as the charge polarity of the molding material particles. This situation is shown in Fig. 2 (d). Fifth, the light source module 30 irradiates shaping light rays to the shaping material particles placed on the shaping stage 21 or the surface of the immediately preceding shaping layer to form molding layers by melting or sintering the shaping material particles. Sixth, the above first to fifth steps are repeatedly performed until the shape of the three-dimensional object is completed.

Next, a method of forming a three-dimensional object using the stereolithography apparatus including the rotation plate 81 as described above will be described. One embodiment of this is shown in Fig. First, the molding material container 11 is filled with molding material particles. 8 (a), when the shaping material supply unit 112 fills the molding material container 11 and projects the positive shaping material particles to a predetermined position of the molding material container 11, the filling blade 111 While moving, the molding material container 11 is filled with the molding material particles, and the remaining molding material particles are removed. Second, the spinning transfer plate 141 rotates and the shaping material container 11 is positioned below the electrode grid 12. Third, the electrode grid 12 moves downward, and the electrode grid 12 and the molding material container 11 form a first relative position with respect to each other. Fourth, a predetermined voltage is applied to at least one working electrode cell 122 selected by the control module 40 to attach the molding material particles to the working electrode cell 122. When the steps up to this point are performed, the state shown in Fig. 8 (b) is achieved. Fifth, the molding stage 21 is positioned below the electrode grid 12 by the rotation (180 degrees) of the rotary transfer board 141. Sixth, the electrode grid 12 moves downward, and the electrode grid 12 and the molding stage 21 form a second relative position with respect to each other. Seventh, by applying a predetermined voltage to the working electrode cell 122, the shaping material particles desorbed from the working electrode cell 122 are placed on the shaping stage 21 or the surface of the immediately preceding shaping layer. When the steps up to this point are performed, the state shown in Fig. 8 (c) is achieved. Eighth, the light source module 30 irradiates shaping light to the shaping material particles placed on the shaping stage 21 or the immediately preceding shaping layer surface to melt or sinter the shaping material particles. Ninthly, the first to eighth steps are repeatedly performed until the shape of the three-dimensional sculpture is completed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it should be understood that various changes and modifications will be apparent to those skilled in the art. Obviously, the invention is not limited to the embodiments described above. Accordingly, the scope of protection of the present invention should be construed according to the following claims, and all technical ideas which fall within the scope of equivalence by alteration, substitution, substitution, Range. In addition, it should be clarified that some configurations of the drawings are intended to explain the configuration more clearly and are provided in an exaggerated or reduced size than the actual configuration.

1: molding material particle
2: Immediate shaping layer
10: Head assembly of the stereolithography device
11: Molding material container
111: Filling blade
112: molding material supplier
12: electrode grid
121: Electrode cell
122: working electrode cell
123: particle attachment surface
123a: depression
124: substrate
125: Bulkhead grid
13: First charging device
14: Feed module

20: Molding stage module
21: Molding stage
30: Light source module
31: line laser light
40: Control module

Claims (17)

A head assembly of a stereolithography apparatus for transitioning and moving shaping material particles to form a shaping layer to be placed on a shaping stage,
A molding material container 11 for supplying molding material particles charged with a predetermined electric charge to an electrode grid;
An electrode grid (12) comprising a plurality of electrode cells (121) arranged in a predetermined pattern;
A first charging device (13) for applying a predetermined voltage to each of the working electrode cells (122) to which the shaping material particles are attached or detached from the electrode cells (121) constituting the electrode grid (12);
Wherein the electrode grid (12) has a first relative position between the electrode grid (12) for receiving the molding material particles from the molding material container (11) and the molding material container (11) The electrode grid 12 and the molding material container 11 to form a second relative position between the electrode grid 12 and the molding stage 21 for seating the molding material particles on the molding stage 21, ) And a transfer module (14) functioning to relatively move the shaping stages (21) relative to each other;
, ≪ / RTI >
The attaching and detachment of the shaping material particles to the working electrode cell 122 can be carried out between the working electrode cell 122 generated by the predetermined voltage applied from the first charging device 13 and the shaping material particles Characterized in that it is based on the electrical attraction and repulsion. The method according to claim 1,
Wherein the electrode grid (12) comprises a substrate on which the electrode cells (121) are formed, and the electrode cells (121) are formed in a flat pad shape on the substrate Of the head assembly. The method of claim 2,
Wherein the electrode grid further comprises a diaphragm grid formed of non-conductive partition walls surrounding each of the electrode pads of the flat pad shape, and when voltage is applied to the working electrode cell, Wherein the space is filled with a part or all of a space defined by the partition wall and the electrode pad of the flat pad shape. The method according to claim 1,
The electrode grid (12) includes a substrate on which the electrode cell (121) is formed, and the electrode cell (121) is formed in a three-dimensional shape protruding from the substrate surface Head assembly of a stereolithography device.

The method of claim 4,
And a concave depression (123a) is formed in the tip of the protruding three-dimensional shape so that the molding material particles can be embedded. The method according to claim 1,
Wherein the transfer module (14) relatively moves the molding material container (11) and the molding stage (21) relative to the electrode grid (12). The method according to claim 1,
Wherein the transfer module (14) relatively moves the electrode grid (12) relative to the molding material container (11) and the molding stage (21). The method according to claim 1,
Characterized in that the molding material container (11) has a shape in which the molding material particles are stacked and the upper surface side thereof is opened so that the electrode grid (12) can be input and output. The method according to claim 1,
Characterized in that the molding material container (11) further comprises a molding material surface planarizing section having a function of flattening the surface of the loaded molding material particles. The method according to claim 1,
Characterized in that the molding material container (11) further comprises a second charging device for supplying chargeable formable material particles and charging them with a predetermined charge. A head assembly of a stereolithography apparatus according to any one of claims 1 to 10;
A shaping stage module (20) comprising a shaping stage (21) which is attached to the working electrode cell (122) and the shaping material particles transferred thereon are detached from the working electrode cell (122) and then mounted on the upper surface thereof;
A light source module (30) for molding the molding layer by melting or sintering the molding material particles seated on the molding stage (21);
The working electrode cell 122 to which the shaping material particles adhere is selected every time the shaping layers are formed and the shaping material container 11, the first charging device 13, the shaping stage module 20, A control module (40) for driving and controlling the module (14) and the light source module (30) in cooperation with each other;
And a control unit for controlling the operation of the stereolithography device. The method of claim 11,
Wherein the light source module (30) is a line laser. The method of claim 11,
Wherein the stereolithography apparatus comprises at least two electrode grids (12). The method of claim 11,
The transfer module (14)
The shaping material container 11 and the shaping stage module 20 are transported so as to be aligned below the electrode grid 12 while the shaping material container 11 and the shaping material container 11 And a rotary transfer plate (141) having the molding stage (21). 15. The method of claim 14,
Wherein the molding material container (11) and the molding stage (21) are formed on the upper surface of the rotary transfer plate (141). A method of molding a three-dimensional object using the stereolithography apparatus according to claim 11,
(i) transferring (s10) the transfer module (14) such that the electrode grid (12) and the molding material container (11) have the first relative position with each other;
(ii) attaching the shaping material particles to the working electrode cell (122) by applying a predetermined voltage to at least one working electrode cell (122) selected by the control module (40);
(iii) transferring (s30) the transfer module (14) so that the electrode grid (12) and the shaping stage (21) have the second relative position with each other;
(iv) a predetermined voltage is applied to the working electrode cell 122 in the step (ii) to deposit the shaping material particles desorbed from the working electrode cell 122 on the shaping stage 21 or the surface of the immediately preceding shaping layer Step s40;
(v) a step of melting or sintering the molding material particles by irradiating molding light to the molding material particles placed on the molding stage (21) or the immediately preceding molding layer face in the step (iv) s50);
(vi) repeating the steps (i) to (v) until the shape of the stereolithography is completed (s60);
And a second step of forming a three-dimensional shape using the three-dimensional molding apparatus. A method for molding a three-dimensional object using the stereolithography apparatus according to claim 15,
(a) filling the molding material container 11 with molding material particles (s100);
(b) positioning (s200) the molding material container (11) below the electrode grid (12) by rotation of the rotary transfer plate (141);
(c) the electrode grid (12) moves downward to form the first relative position with the electrode grid (12) and the molding material container (11) (s300);
(d) applying a predetermined voltage to at least one working electrode cell (122) selected by the control module (40) to attach the shaping material particles to the working electrode cell (s400);
(e) placing (s500) the shaping stage (21) below the electrode grid (12) by rotation of the rotary transfer board (141);
(f) step (s600) wherein the electrode grid (12) moves downward to form the second relative position with respect to the electrode grid (12) and the shaping stage (21);
(g) applying a predetermined voltage to the working electrode cell 122 in the step (d) so that the shaping material particles desorbed from the working electrode cell 122 are placed on the shaping stage 21 or the surface of the immediately preceding shaping layer Step s700;
(h) a step of irradiating molding light to the shaping material particles placed on the shaping stage (21) or the pre-shaping layer surface in step (g) to melt or sinter the shaping material particles (s800);
(i) repeating the steps (a) to (h) (s900) until the shape of the three-dimensional object is completed;
And a second step of forming a three-dimensional shape using the three-dimensional molding apparatus.

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