WO2020071626A1

WO2020071626A1 - 3d printer

Info

Publication number: WO2020071626A1
Application number: PCT/KR2019/009522
Authority: WO
Inventors: 김병서; 박영민; 노정환; 송명근
Original assignee: 홍익대학교세종캠퍼스산학협력단
Priority date: 2018-10-02
Filing date: 2019-07-31
Publication date: 2020-04-09
Also published as: KR20200039048A; KR102165808B1

Abstract

The present invention relates to a 3D printer. A 3D printer according to an embodiment of the present invention comprises: a nozzle part (10) for melting and discharging a solid-phase thermoplastic material (M); a workbench (20) disposed below the nozzle part (10); a nozzle moving part (30) which cures and laminates the thermoplastic material (M) upward on the upper surface of the workbench (20) while moving the nozzle part (10) in X-axis and Y-axis directions to form a first molded product (P1); an elevating part (40) for elevating the workbench 20 in a Z-axis direction; a water reservoir (50) disposed below the workbench (20) to accommodate a liquid-phase photocurable resin (R), and being open at the top; a molding table (60) which is connected to the elevating part (40) to be disposed between the workbench (20) and the water reservoir (50), the lower surface of which is immersed in the photocurable resin (R) through the upper portion of the water reservoir (50) and then raised; and a light irradiation part (70) which projects light onto the water reservoir (50) while changing a projection direction, and cures and laminates the photocurable resin (R) downward on the lower surface of the molding table (60) to form a second molded product (P2).

Description

3D printer

The present invention relates to a 3D printer.

3D printer is a machine that photographs a three-dimensional three-dimensional shape according to the input design, and was originally developed to produce a prototype in a company, but recently, the material range such as nylon and metal has been extended beyond the initial plastic material, and industrial prototype In addition to manufacturing, it has entered the commercialization stage in various fields.

The principle of 3D printer is similar to that of inkjet printer. The inkjet printer, which is a 2D printer, receives a digitized file and prints a 2D image such as a letter or picture by spraying ink on paper while moving the ink jet nozzle in the X and Y axes. Adding motion to create a three-dimensional shape.

Conventional 3D printers are composed of an extruder that supplies filament, a hot end nozzle that melts and sprays the filament. The filament supplied through the extruder is melted by the heater of the hot end nozzle and sprayed through the nozzle. At this time, the hot end nozzle moves in a three-axis direction to produce a three-dimensional article by laminating the filament thin film.

The conventional 3D printer adopting the above method has a simple structure, which is very easy to manufacture, can reduce manufacturing cost, and has the advantage of being able to rapidly perform molding, but has a problem that the surface is rough and cannot be precisely formed. To solve this problem, various 3D printers have been developed, but since the use of materials according to the printing method is limited, it is necessary to selectively use the printer to achieve the desired precision. Accordingly, the user is forced to purchase several 3D printers with different printing materials and methods, and a method for solving such a problem is urgently required.

The present invention is to solve the above-mentioned problems of the prior art, one aspect of the present invention is to combine the elevating and descending worktable and the molding table to melt the thermoplastic material through the nozzle at the top to mold the molded product on the worktable. In the lower part, it is intended to provide a 3D printer capable of molding other molded products on a molding table by irradiating light to a photocurable resin.

In addition, another aspect of the present invention is to provide a 3D printer capable of reducing vibrations generated when the worktable and the molding table move up and down during the 3D printing process and prevent heat transfer generated during molding by the thermoplastic material at the top. .

The 3D printer according to the present invention includes a nozzle unit that melts and discharges a solid thermoplastic material; A worktable disposed under the nozzle unit; A nozzle moving unit for forming the first molded product by hardening and stacking the thermoplastic material upward on the upper surface of the work table while moving the nozzle unit in the X-axis and Y-axis directions; An elevating and descending unit for elevating and descending the work table in the Z-axis direction; A water tank disposed under the worktable, accommodating a liquid photocurable resin, and having an open top; A molding table connected to the elevating part so as to be disposed between the work table and the water tank, the lower surface being immersed in the photocurable resin through the upper part of the water tank and then rising; And a light irradiating unit that projects light to the water tank while changing the projection direction, and cures and stacks the photocurable resin downward on the lower surface of the molding table to form a second molded product.

In addition, in the 3D printer according to the present invention, the elevating unit is a binding bundle for coupling the lower surface of the worktable and the upper surface of the molding table; A rod having a rod shape, disposed along the Z-axis direction while passing through the coupling bundle, and having a thread formed on an outer surface to rotate and elevate the coupling bundle while rotating; And a rod-shaped, a pair of guide rods arranged along the Z-axis direction so as to face each other with the screw rods interposed therebetween, and guiding the lifting and lowering of the coupling bundle.

In addition, in the 3D printer according to the present invention, the lower end of the worktable is detachably attached to the upper surface of the front end of the coupling bundle, and both side ends are bent downward so as to face each other, and the perforation through which the threaded rod passes at the rear end. A coupling piece provided; It is formed in the form of a block with an opening formed at the rear end, the upper surface of the molding table is coupled to the molding table assembly; A front end inserted into and fastened by the opening of the forming table coupling body, and a fastening part disposed to be surrounded by a lower surface and inner surfaces of both ends of the coupling piece; And a sliding mount disposed on outer surfaces of both ends of the coupling piece and having a through hole through which the guide rod passes.

In addition, in the 3D printer according to the present invention, the coupling bundle further includes a coupling screw whose end protrudes into the opening through the front surface of the modeling assembly and is screwed to the front end of the fastening portion.

In addition, in the 3D printer according to the present invention, the coupling bundle at least one or more shaft portions protruding from the outer surfaces of both ends of the coupling piece, respectively; And a counterweight attached to the shaft to adjust the balance of the coupling piece.

In addition, the 3D printer according to the present invention, disposed on the upper surface of the rear end of the engaging piece, the nut housing having a nut hole penetrated to communicate with the perforation; And at least one ball disposed between the screw rod and the nut hole.

In addition, in the 3D printer according to the present invention, the sliding mounts are respectively disposed on the upper and lower surfaces of the outer surfaces of both ends of the coupling piece, and rolling bearings disposed between the inner surface of the through hole and the outer surface of the guide rod. do.

In addition, in the 3D printer according to the present invention, in the form of a plate, disposed between the lower surface of the worktable and the coupling bundle, a heat insulating plate that blocks the transfer of heat generated when the first molded article is formed; It includes more.

In addition, in the 3D printer according to the present invention, at least two or more stoppers projecting downward to face each other from both edges of the insulating plate; And a bracket connecting the stopper and the coupling bundle.

In addition, in the 3D printer according to the present invention, the first molded article and the second molded article is provided with an inner space to be molded, the inner and lower inner chambers are partitioned by the insulating plate; A circulation fan disposed in each of the upper and lower parts of the chamber to circulate the internal air; And an exhaust portion disposed on each of the inner and lower portions of the chamber to discharge internal air to the outside of the chamber.

Features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, the terms or words used in the specification and claims should not be interpreted in a conventional and lexical sense, and the inventor can properly define the concept of terms in order to explain his or her invention in the best way. Based on the principle that it should be interpreted as meanings and concepts consistent with the technical spirit of the present invention.

According to the present invention, the worktable and the molding table are combined with each other to move up and down, and in the upper region, a thermoplastic material can be melted and discharged through the nozzle to the working table, and in the lower region, the photocurable resin is irradiated with light to be molded in the molding table. Therefore, by using different materials with one 3D printer but molding in a manner suitable for the material, an optimized molded product can be manufactured according to a 3D molding process desired by the user.

In addition, by selecting a thermoplastic material or a photo-curable resin and performing a molding process, by reducing the vibration generated while the worktable and the molding table move up and down, and prevent heat transfer generated during molding by the thermoplastic material, any one process Stable and precise 3D molding can be performed by excluding effects on other processes.

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

2 is a front view of a 3D printer according to an embodiment of the present invention.

3 to 4 are exploded perspective views of the coupling bundle shown in FIG. 2.

5 is a front view of a 3D printer according to another embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments that are associated with the accompanying drawings. It should be noted that in this specification, when adding reference numerals to components of each drawing, the same components have the same number as possible, even if they are displayed on different drawings. Further, terms such as “first” and “second” are used to distinguish one component from other components, and the component is not limited by the terms. Hereinafter, in describing the present invention, detailed descriptions of related well-known technologies that may unnecessarily obscure the subject matter of the present invention are omitted.

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

1 is a perspective view of a 3D printer according to an embodiment of the present invention, FIG. 2 is a front view of a 3D printer according to an embodiment of the present invention, and FIGS. 3 to 4 are exploded perspective views of the coupling bundle shown in FIG. 2.

1 to 2, a 3D printer according to an embodiment of the present invention includes a nozzle unit 10 for melting and discharging a solid thermoplastic material (M); A work table 20 disposed under the nozzle unit 10; While moving the nozzle unit 10 in the X-axis and Y-axis direction, the nozzle moving unit 30 to mold the first molded product P1 by hardening and stacking the thermoplastic material M upward on the upper surface of the work table 20; An elevation unit 40 for elevating and descending the work table 20 in the Z-axis direction; A water tank 50 disposed under the work table 20, accommodating a liquid photocurable resin R, and having an open top; A molding table 60 which is connected to the elevating part 40 so as to be disposed between the work table 20 and the water tank 50, so that the lower surface is immersed in the photocurable resin R through the upper part of the water tank 50 and then rises; And a light irradiating unit 70 that projects light to the water tank 50 while changing the projection direction, and cures and stacks the photocurable resin R downward on the lower surface of the molding table 60 to form the second molded product P2. Includes.

The present invention relates to a 3D printer that molds a three-dimensional three-dimensional shape, and the material is limited to a filament made of a thermoplastic material (M) in a 3D printer that adopts a conventional Fused Deposition Molding (FDM) method. There is a problem in that the surface roughness and precision of the molded article are poor, and it has been devised as a solution to this.

Specifically, the 3D printer according to the present invention includes a nozzle unit 10, a workbench 20, a nozzle moving unit 30, an elevating unit 40, a water tank 50, a molding stand 60, and a light irradiation unit 70 It includes.

The nozzle unit 10 is implemented to melt and discharge the solid thermoplastic material (M). The solid thermoplastic material (M) is a material having a property of being melted and cured when heat is applied, and is not limited if it is a three-dimensional printing material such as, for example, plastic filament made of ABS or PLA. You can choose.

The nozzle unit 10 may be embodied as a heater for melting a solid thermosetting material and a nozzle for discharging the molten material to the outside. Further, in order to mix a plurality of thermoplastic materials (M) having different colors and properties, a material mixing part capable of mixing the molten material and supplying it to the nozzle may be additionally formed. Such a means, for example, is provided with a plurality of supply pipes so that a plurality of materials are supplied, and a heater heats a point where the supply pipes converge to melt and mix the material, and a discharge pipe communicating the convergence point and the nozzle It may be provided and implemented. However, the scope of the right should not be limited by the above configuration, as long as the nozzle unit 10 is a means capable of melting and discharging the thermoplastic material M to the outside.

The work table 20 is disposed under the nozzle unit 10 to provide a region where the discharged thermoplastic material M is stacked, thereby supporting the molded first molded article P1. In order to perform this function, the work table 20 may be formed in a plate shape, for example.

The nozzle moving part 30 is a moving means for moving the nozzle part 10 in the X-axis and Y-axis directions, discharging and stacking the thermoplastic material (M) on the upper surface of the worktable (20) in the left-right direction and stacking the first molded product. (P1) is molded. Here, the nozzle moving unit 30 may move only the nozzles of the entire configuration of the nozzle unit 10, or a configuration thereof. The nozzle moving unit 30 may be implemented by a known means for moving a nozzle of a conventional 3D printer, and detailed description is omitted.

The elevating and descending portion 40 is a means for elevating and descending the work table 20 in the Z-axis direction, that is, in the vertical direction, and the distance between the nozzle part 10 and the work table 20 while forming the first molded product P1. Adjust. The elevating portion 40 may be implemented with a coupling bundle 41, a screw rod 43, and a pair of guide rods 45.

Here, the coupling bundle 41 combines the lower surface of the worktable 20 and the upper surface of the molding table 60 to be described later. Details of the coupling bundle 41 will be described later. The screw rod 43 is a member formed in a rod shape, and is disposed along the Z-axis direction while passing through the coupling bundle 41, and a thread is formed on its outer surface. Therefore, when the screw rod 43 rotates with the Z axis as the rotational axis, the engagement bundle 41 can be moved up and down according to the rotational direction. On the other hand, the pair of guide rods 45 are each formed in a rod shape, and are arranged along the Z-axis direction so as to face each other with the screw rods 43 interposed therebetween to penetrate the left and right sides of the coupling bundle 41, thereby engaging The bundle 41 is guided to slide in the vertical direction while maintaining the right and left parallel.

The water tank 50 is provided with an interior space capable of accommodating the liquid photocurable resin R, and is an open container at the top, which is disposed under the work table 20. The photocurable resin (R) is a polymer material that exists in the liquid phase and cures when exposed to light such as laser and UV, and is a material for manufacturing the second molded product (P2).

The molding table 60 attaches the second molded product P2 to the lower surface. Therefore, the lower surface of the molding table 60 is formed in a plane having a certain area. The molding table 60 is disposed between the work table 20 and the water tank 50, and is connected to the lifting part 40, so as to move up and down, is immersed in the photocurable resin R through the open upper part of the water tank 50. The upper part of the second molded product P2 is attached to the lower surface thereof, and as it rises, the photocurable resin R is cured and stacked downward to mold the lower part of the second molded product P2.

The light irradiation unit 70 is a device that projects light to the water tank 50 so that the second molded article P2 is made. At this time, in order to mold the second molded article P2, since the projection direction of light needs to be changed, it can be implemented, for example, as a light source generating light and a galvanometer for switching the projection direction. Here, the light source may be a laser oscillator, a UV lamp, or the like, depending on the light to be irradiated.

Comprehensively, according to the present invention, the work table 20 and the molding table 60 are configured to be combined with each other by the elevating part 40 to move up and down, and the nozzle part 10 in the upper region uses the thermoplastic material (M) Since the first molded product P1 can be molded by melt-discharging to (20), and the second molded product P2 can be molded on the molding table 60 by irradiating light to the photocurable resin R in the lower region, By using different materials with one 3D printer and molding each molded product in a manner suitable for the material, an optimized molded product can be manufactured according to a user's desired 3D molding process. At this time, since the work table 20 and the molding table 60 move up and down together, it is a principle that the first molded product P1 and the second molded product P2 are molded separately, but depending on the shape of the molded product, two molded products are molded at the same time. It may be.

Hereinafter, the coupling bundle 41 will be described in detail.

3 to 4, the coupling bundle 41 may include a coupling piece 41a, a molding stand coupling body 41b, a fastening portion 41c, and a sliding mount 41d.

The coupling piece 41a is detachably attached to the lower surface of the worktable 20 on the upper surface of the front end, and both side ends s are bent downward and formed to face each other. In addition, the rear end is provided with a perforation so that the screw rod 43 can pass, the screw rod 43 and the coupling piece 41a are connected to each other.

The molding table assembly (41b) is a member for joining the molding table 60 to the engaging piece (41a), is formed in a block shape as a whole, provided with an opening (b) at the rear end, the lower portion is combined with the upper surface of the molding table (60) .

The fastening portion 41c is a member that fastens the forming table engaging body 41b and the engaging piece 41a. The upper surface and both side surfaces of the fastening part 41c are inserted and arranged in the bonding piece 41a so as to be surrounded by the lower surface of the bonding piece 41a and the inner surface of both side ends s, but the outer surface and the bonding piece of the front end of the fastening part 41c A gap is formed between the inner surfaces of (41a). In addition, the front end of the fastening portion 41c is inserted into and fastened to the opening portion b of the molding stand assembly 41b, and is formed in a shape corresponding to the shape of the opening portion b. On the other hand, the clearance is filled by the outer surface forming the opening (b) of the molding table assembly (41b) with the front end of the fastening portion (41c) inserted. Here, since the rear end of the fastening portion 41c is formed to have a wider width than its front end, both side surfaces of the rear end can be fixed in close contact with the inner surfaces of both side ends s of the coupling piece 41a (see FIG. 4). At this time, both side surfaces of the rear end of the fastening portion 41c and both side ends s of the coupling piece 41a may be securely fixed through a fastener such as a bolt.

Sliding mount (41d) is a member connecting the guide rod 45 and the engaging piece (41a), is formed in a block shape having a through hole (d) penetrating in the vertical direction, both ends of the engaging piece (41a) (s) are respectively coupled to the outer surface, the guide rod 45 connects the coupling piece 41a and the guide rod 45 while passing through the through hole (d).

On the other hand, while the engaging bundle 41 is elevating and descending according to the rotation of the threaded rod 43, the gap between the forming body engaging body 41b and the fastening portion 41c, the perforation of the engaging piece 41a and the threaded rod 43 Vibration may occur due to the clearance and friction between, and the clearance and friction between the through hole (d) of the sliding mount (41d) and the guide rod (45), and the present invention can provide vibration reduction means as follows. .

First, the coupling bundle 41 may further include a coupling screw 41e. The coupling screw 41e is composed of a head and a screw portion protruding in one direction from the center of the head, and the end of the screw portion penetrates through the front surface of the molding stand coupling body 41b and protrudes into the opening portion b, and the front end portion of the fastening portion 41c And screw. Due to this, even if there is a gap between the forming table coupling body 41b and the fastening portion 41c, both of the 41b and 41c can be firmly coupled, thereby minimizing vibration. At this time, the head of the coupling screw 41e can be exposed by protruding from the front surface of the forming stand coupling body 41b, and the non-slip processing is performed on the outer circumferential surface in an uneven shape so that the user can easily fasten or release the coupling screw 41e. , A driver groove may be provided on the upper surface of the head to enable fastening through a driver or the like.

In addition, the coupling bundle 41 may further include a shaft portion (41f), and a counterweight (41g). Due to the clearance between the coupling piece 41a and the screw rod 43 and between the sliding mount 41d and the guide bar 45, the horizontal of the left and right sides of the coupling piece 41a may not fit. Thus, in the present invention, at least one or more shaft portions 41f protruding from the outer surfaces of both side ends s of the engaging piece 41a to the left and right are formed, and the counterweight 41g is attached to the left and right shaft portions 41f. , Adjust the left and right balance of the engaging piece (41a). In one example, the shaft portion 41f is formed in the form of a nut with a thread formed on the outer surface, and the counterweight 41g can be formed in the form of a butterfly nut, in which case the user adjusts the position by tightening or loosening the butterfly nut to adjust the position. Can be adjusted.

In order to compensate for clearance and friction between the threaded rod 43 and the engaging piece 41a, the present invention may further include a nut housing 80 and a ball (not shown). The nut housing 80 is a member that is disposed on the upper surface of the rear end of the engaging piece 41a, and has a nut hole 81 penetrated to communicate with the perforation of the engaging piece 41a. Therefore, the threaded rod 43 passes through the perforation and the nut hole 81 of the engaging piece 41a. The steel ball is a ball formed in a spherical shape, is disposed between the screw rod 43 and the nut hole 81, and is in close contact between the screw rod 43 and the nut hole 81 to solve the clearance, and the screw rod The friction generated when (43) rotates is reduced to suppress vibration.

In addition, the sliding mount (41d) is spaced apart from the upper and lower sides of the outer side (s) of both sides of the coupling piece (41a) are disposed one by one, the through hole (d) of the sliding mount (41d) inner surface and guide rod (45) A rolling bearing (not shown) may be disposed between the outer surfaces of the. In this case, the two sliding mounts 41d are vertically arranged, and one guide rod 45 is the two sliding mounts based on one side end which is one of both side ends s of the coupling piece 41a ( Since it passes through the through hole (d) of 41d), each sliding mount (41d) and the rolling bearing are fixed to different upper and lower regions of the guide rod (45). Accordingly, any one of the guide rods 45 is supported by a double bearing structure to reduce vibration.

On the other hand, the 3D printer according to the present invention performs 3D molding with different materials and methods in the upper and lower regions. Since the process conditions of the upper and lower portions must be different, the upper and lower regions are not affected by the following. The same means can be added.

5 is a front view of a 3D printer according to another embodiment of the present invention, as shown in FIG. 5, the 3D printer according to another embodiment of the present invention may further include a heat insulating plate 90.

The insulating plate 90 is a member formed in a plate shape using an insulating material. The heat insulating plate 90 is arranged and fixed between the lower surface of the work table 20 and the coupling bundle 41. When the first molded article (P1, see FIG. 1) is molded, the thermoplastic material absorbs heat, melts, and then cures while dissipating heat, so that the heat moves downward to affect the photocurable resin in the water tank 50. As it can, the heat transmitted from the upper portion to the lower portion of the insulating plate 90 is blocked.

On the other hand, the 3D printer according to the present invention, while lifting and descending the work table 20 and the molding table 60, the material is stacked upward or downward to form, so if the height of the molding table 60 is too low, it collides with the water tank 50 can do. Accordingly, the present invention may further include a stopper 100 and a bracket 110.

The stopper 100 may protrude downwardly so as to face each other from both edges of the heat insulating plate 90, and may be formed of at least two or more. Since the stopper 100 has a height such that the molding table 60 and the water tank 50 do not collide with each other, when the molding table 60 descends, the stopper 100 comes into contact with the pedestal supporting the water tank 50 , Prevents the collision of the molding table 60 and the water tank 50. Here, when it comes into contact with the pedestal, since the shock can be transmitted to the work table 20 and the molding table 60 through the heat insulating plate 90, the stopper 100 is made of a material that can absorb the shock, or separately, such as a spring or a damper Shock absorbing device may be mounted on the stopper (100).

The bracket 110 is fixed to the stopper 100 by connecting the stopper 100 and the coupling bundle 41 in order to prevent deformation and damage due to the impact that the stopper 100 hits the pedestal.

In addition, the 3D printer according to the present invention further includes a chamber 120, a circulation fan 130, and an exhaust unit 140 to circulate and discharge air in the upper and lower regions based on the insulating plate 90 can do.

The chamber 120 is a member having an internal space in which the first molded article (P1, see FIG. 1) and the second molded article (P2, see FIG. 2) can be molded, and the nozzle unit 10 and the work table 20 are described above. ), The nozzle moving part 30, the elevating part 40, the water tank 50, the molding table 60, the insulating plate 90, etc. are mounted or disposed therein. Here, the interior space of the chamber 120 is divided into an inner upper portion and an inner lower portion by the insulating plate 90. At this time, the edge of the heat insulating plate 90 is in close contact with the inner surface of the chamber 120, and all or part of the boundary may be sealed.

The circulation fan 130 and the exhaust unit 140 may be disposed in each of the inner upper portion and the inner lower portion of the chamber 120 partitioned as described above. The circulation fan 130 is a device provided to circulate the internal air, and the exhaust unit 140 is a device that discharges the internal air to the outside of the chamber 120 and may be implemented through a duct, an exhaust fan, an exhaust pump, and the like.

Although the present invention has been described in detail through specific embodiments, the present invention is specifically for describing the present invention, and the present invention is not limited to this, and by those skilled in the art within the technical spirit of the present invention. It is clear that the modification and improvement are possible.

All simple modifications or changes of the present invention belong to the scope of the present invention, and the specific protection scope of the present invention will be clarified by the appended claims.

10: nozzle unit 20: worktable

30: nozzle moving portion 40: elevating portion

41: coupling bundle 43: screw rod

45: guide rod 41a: connecting piece

41b: molding stand assembly 41c: fastening

41d: Sliding mount 41e: Coupling screw

41f: shaft 41g: counterweight

50: tank 60: molding table

70: light irradiation unit 80: nut housing

81: nut hole 90: insulation plate

100: stopper 110: bracket

120: chamber 130: circulation fan

140: exhaust portion P1: first molded article

P2: Second molded article M: Thermoplastic material

R: photocurable resin

According to the present invention, the molded article can be molded on a worktable by melt-discharging a thermoplastic material through a nozzle at the top centering on a worktable and a molding table that are combined and elevated, and at the bottom, other molded products are molded on the mold. As for a 3D printer that can be used, industrial applicability can be recognized.

Claims

A nozzle unit that melts and discharges the solid thermoplastic material;

A worktable disposed under the nozzle unit;

A nozzle moving unit for forming the first molded product by hardening and stacking the thermoplastic material upward on the upper surface of the work table while moving the nozzle unit in the X-axis and Y-axis directions;

An elevating and descending unit for elevating and descending the work table in the Z-axis direction;

A water tank disposed under the worktable, accommodating a liquid photocurable resin, and having an open top;

A molding table connected to the elevating part so as to be disposed between the work table and the water tank, the lower surface being immersed in the photocurable resin through the upper part of the water tank and then rising; And

A 3D printer comprising; a light irradiating unit that projects light to the water tank while changing a projection direction, and cures and stacks the photocurable resin downward on the bottom of the molding table to form a second molded product.
The method according to claim 1,

The elevating part

A coupling bundle for joining the lower surface of the worktable and the upper surface of the molding table;

A rod having a rod shape, disposed along the Z-axis direction while passing through the coupling bundle, and having a thread formed on an outer surface to rotate and elevate the coupling bundle while rotating; And

3D printer comprising a; rod-shaped, a pair of guide rods disposed along the Z-axis direction so as to face each other with the screw rod therebetween, to guide the lifting and lowering of the coupling bundle.
The method according to claim 2,

The binding bundle

A coupling piece having a lower surface of the worktable detachably attached to an upper surface of the front end, and both side ends bent downward to face each other, and having a perforation through which the screw rod passes at the rear end;

It is formed in the form of a block with an opening formed at the rear end, the upper surface of the molding table is coupled to the molding table assembly;

A front end inserted into and fastened by the opening of the forming table coupling body, and a fastening part disposed to be surrounded by a lower surface and inner surfaces of both ends of the coupling piece; And

A 3D printer comprising; a sliding mount disposed on outer surfaces of both ends of the coupling piece and having a through hole through which the guide rod passes.
The method according to claim 3,

The binding bundle

A 3D printer further comprising: a coupling screw whose end protrudes into the opening through the front surface of the modeling assembly and is screwed to the front end of the fastening portion.
The method according to claim 3,

The binding bundle

At least one or more shaft portions protruding from outer surfaces of both side ends of the coupling piece; And

A 3D printer further comprising a counterweight attached to the shaft to adjust the balance of the coupling piece.
The method according to claim 3,

A nut housing disposed on an upper surface of the rear end of the coupling piece and having a nut hole penetrated to communicate with the hole; And

3D printer further comprising; at least one ball (ball) disposed between the screw rod and the nut hole.
The method according to claim 3,

The sliding mounts are disposed one on each of the upper and lower sides of the outer surfaces of both ends of the coupling piece,

A 3D printer further comprising; a rolling bearing disposed between the inner surface of the through hole and the outer surface of the guide rod.
The method according to claim 2,

A 3D printer further comprising a plate-shaped, heat-insulating plate disposed between the lower surface of the worktable and the coupling bundle to block the transfer of heat generated when the first molded article is molded.
The method according to claim 8,

At least two or more stoppers projecting downward to face each other from both edges of the heat insulating plate; And

3D printer further comprising; a bracket connecting the stopper and the coupling bundle.
The method according to claim 8,

A chamber having an inner space in which the first molded article and the second molded article can be molded, and the inner upper portion and the inner lower portion being partitioned by the insulating plate;

A circulation fan disposed in each of the upper and lower parts of the chamber to circulate the internal air; And

3D printer further comprising; an exhaust portion disposed on each of the inner and lower portions of the chamber to discharge internal air to the outside of the chamber.