Molding device

Abstract

To provide a molding device capable of suitably performing production of a molding.SOLUTION: A molding device includes a barrel 82 for supplying molding material, a heater 84 for heating the material supplied into the barrel 82, a nozzle 85 for discharging the heated and melted material, and a cooling and relaxation blower 71 that sends air warmed by the heater 84 to the tip of the nozzle 85.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a molding apparatus. [Background technology]

[0002] In recent years, modeling devices have been used to create three-dimensional objects. One modeling device method is the fused deposition modeling method. In the fused deposition modeling method, pellets or filaments of thermoplastic resin, which are the modeling material, are supplied to a print head together with a colorant, so that the pellets or filaments ejected from the print head are colored. For example, Patent Document 1 discloses that when the filament is supplied to the print head, the filament is coated with a colorant before being supplied to the print head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2014-516829 Summary of the Invention [Problem to be solved by the invention]

[0004] In the fused deposition modeling method, the material ejected from the nozzle cools and shrinks rapidly, which causes thermal stress in the object, and if the thermal stress is large, the object will warp or crack. In particular, materials with high viscosity or low melt flow rate have a large shrinkage rate and large thermal stress, making these materials unable to be used for practical manufacturing of objects.

[0005] In order to reduce the effects of material shrinkage, attempts have been made to prevent the object from shrinking suddenly during printing by using a high-temperature printing table or furnace. However, this can lead to deformation of the object during printing (e.g., sagging) because additional material is layered on top of the object before it has fully solidified.

[0006] In view of the above, an object of the present invention is to provide a modeling apparatus that can suitably manufacture a modeled object, for example, that can suppress the influence of shrinkage of a material dispensed during the manufacture of a modeled object or deformation of the modeled object. [Means for solving the problem]

[0007] A modeling apparatus according to a first aspect of the present invention comprises: a barrel into which material for molding is supplied; a heater that heats the material supplied into the barrel; a nozzle for discharging the heated and melted material; and a blower that sends the air heated by the heater to the tip of the nozzle.

[0008] According to the above configuration, the cooling rate of the material discharged from the nozzle tip is slowed down, which reduces the effect of shrinkage of the discharged material during the production of a model, allowing the use of a material with a high viscosity or a low melt flow rate as the modeling material.

[0009] The air conditioner may further include a deflector that deflects the air blown by the blower.

[0010] According to the above configuration, the hot air can be more reliably directed at the tip of the nozzle.

[0011] a heat source other than the heater, The heating device may further include an additional blower that sends air heated by the heat source to the tip of the nozzle.

[0012] According to the above configuration, the cooling rate of the material discharged from the nozzle tip can be made slower.

[0013] An air passage for suppressing diffusion of air heated by the heater may be provided in at least a part of the path from the heater to the tip of the nozzle.

[0014] According to the above configuration, the cooling rate of the material discharged from the nozzle tip can be made slower.

[0015] A modeling apparatus according to a second aspect of the present invention comprises: The machine is equipped with a blower that blows air at a temperature lower than the melting temperature of the material being used for modeling to the object being modeled on the modeling table.

[0016] According to the above configuration, deformation (for example, sagging) of the object during modeling can be suppressed. [Effects of the Invention]

[0017] According to the present invention, it is possible to provide a modeling apparatus that can suitably manufacture a modeled object, for example, that can suppress the influence of shrinkage of a material dispensed during the manufacture of a modeled object or the deformation of the modeled object. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of a molding apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a print head of the modeling apparatus according to the present embodiment. [Figure 3] FIG. 2 is a front view of the print head of the modeling apparatus according to the present embodiment, with three colorant injection mechanisms located in front of the barrels omitted. [Figure 4] FIG. 10 is a perspective view of a molding table and a molded object cooling unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0019] A modeling apparatus 100 according to an embodiment of the present invention will be described with reference to the drawings. The modeling apparatus 100 is an apparatus (3D printer) that models a three-dimensional object using an additive manufacturing method. The modeling apparatus used in this embodiment is, for example, a fused deposition modeling (FDM) apparatus that melts and layers pellets made of thermoplastic resin.

[0020] 1, the X direction is defined as the "left-right direction," the Y direction is defined as the "front-rear direction," and the Z direction perpendicular to the X and Y directions is defined as the "up-down direction."

[0021] (Overview of the modeling apparatus 100) As shown in FIG. 1 , the modeling apparatus 100 is formed by assembling a plurality of housing units. The modeling apparatus 100 includes a bottom housing unit 10, a pair of side housing units 20, a pair of upper beam units 30 connecting the pair of side housing units 20, an upper housing unit 40 mounting a first print head 1A and a second print head 1B as working heads, a modeling table 50 on which a modeled object is placed, and a control unit 300. The first print head 1A and the second print head 1B melt pellets made of thermoplastic resin and eject them toward the modeling table 50. The bottom housing unit 10, the side housing unit 20, the upper beam unit 30, the upper housing unit 40, and the modeling table 50 are housing units that form the housing of the modeling apparatus 100.

[0022] A pair of side housing units 20, aligned left and right, are installed on the edges of the top surface of the bottom housing unit 10 and form the sides of the modeling apparatus 100. Each of the pair of side housing units 20 has an elevating mechanism 200 in the center. The pair of elevating mechanisms 200 move the modeling table 50 up and down.

[0023] The pair of upper beam units 30 extend in the left-right direction and are arranged facing each other in the front-rear direction. The pair of upper beam units 30 connect the upper parts of the pair of side housing units 20.

[0024] The upper housing unit 40 includes a frame portion 41 and a print head drive mechanism 400 disposed on the upper surface of the frame portion 41. The frame portion 41 is a frame-shaped member formed in a rectangular shape.

[0025] The print head drive mechanism 400 includes a first print head drive mechanism 410 that drives the first print head 1A and a second print head drive mechanism 420 that drives the second print head 1B. The first print head 1A is moved in the front-to-back and left-to-right directions by the first print head drive mechanism 410 under the control of the control unit 300, as indicated by the solid arrows. The second print head 1B is moved in the front-to-back and left-to-right directions by the second print head drive mechanism 420 under the control of the control unit 300, as indicated by the dashed arrows. In this embodiment, the modeling apparatus 100 is a dual-head modeling apparatus equipped with two print heads, but a single print head is also acceptable.

[0026] The modeling table 50 is a platform on which a model is placed, and both opposing edges of the platform 50 are attached to the lifting mechanism 200 .

[0027] The molding apparatus 100 includes a plate-shaped reinforcing member 51 on the outside of the molding apparatus 100 to reinforce the joint between the bottom case unit 10 and the side case unit 20. Furthermore, the molding apparatus 100 includes a plate-shaped reinforcing member 52 on the outside of the molding apparatus 100 to reinforce the joint between the side case unit 20 and the upper beam unit 30.

[0028] The control unit 300 controls the operation of each unit of the modeling apparatus 100. The control unit 300 is composed of a CPU (Central Processing Unit), a memory, etc. The control unit 300 executes a modeling process in accordance with a preset program.

[0029] (About the configuration of print heads 1A and 1B) Next, we will explain the print heads 1A and 1B, which are components of the modeling apparatus 100. Note that the print heads 1A and 1B basically have the same configuration, and to avoid redundant description, only the print head 1A will be explained below.

[0030] As shown in Figures 2 and 3, the print head 1A has a mixing and discharging unit 80 that mixes the material and discharges it onto the modeling table 50, a support unit 90 that supports the mixing and discharging unit 80 and attaches it to the first print head drive mechanism 410, and a discharged material heating unit 70 that heats the discharged material.

[0031] The support unit 90 has a first support plate 91 attached to the first print head drive mechanism 410, a second support plate 92 arranged parallel to the first support plate 91 and spaced apart in the vertical direction, and four connecting pillars 93 connecting the first support plate 91 and the second support plate 92.

[0032] The kneading and discharging unit 80 heats and melts natural pellets supplied as a modeling material while transporting the pellets, and kneads the pellets with a colorant near the discharge port to discharge the material colored to a desired color onto the modeling table 50. As shown in Figures 2 and 3, the kneading and discharging unit 80 has a material input section 81 into which the material is input, a barrel 82 to which the material input from the material input section 81 is supplied, a screw (not shown) that rotates within the barrel 82 and transports the molten material as it rotates, a motor 83 that drives the screw, a heater 84 that heats the material in the barrel 82, a nozzle 85 that discharges the material transported by the screw, a heat dissipation section 86 that dissipates heat between the heater 84 and the motor 83, a cooling fan 87, and a colorant injection mechanism 60 that injects a colorant fluid into the lower part of the barrel 82.

[0033] The material feeding section 81 is a cylindrical member having a passage 81a through which the natural pellets pass. The passage 81a is connected to the hollow portion of the barrel .

[0034] The barrel 82 is a cylindrical member with a circular hollow portion carved out of a cylindrical body. The barrel 82 is arranged with its axis aligned vertically. The barrel 82 has an opening (not shown) that connects the passage 81a of the material feeding section 81 with the hollow portion. The barrel 82 also has a lower portion formed with multiple injection holes 82a through which the colorant is injected. These injection holes 82a are holes that penetrate from the outer peripheral surface of the barrel 82 to the hollow portion, and are formed in the same number as the number of colorant injection mechanisms 60 that can be installed.

[0035] The screw has an upper end connected to a motor 83 and has a spiral groove that can extrude and knead the material.

[0036] The motor 83 is, for example, a servo motor, a stepping motor, or the like, and can rotate an output shaft (not shown) at different rotational speeds under the control of the control unit 300.

[0037] 2 and 3, the heater 84 is provided on the outer periphery of the barrel 82 and heats the supplied material and colorant inside the barrel 82. The heating temperature of the heater, particularly the nozzle temperature, depends on the material, but is, for example, 180°C or higher, particularly 200°C or higher. For example, when polylactic acid (PLA) is used as the material, the heating temperature of the heater is 180°C to 230°C, for example, 190°C to 220°C; when polypropylene (PP) is used, the heating temperature is 210°C to 250°C, for example, 220°C to 240°C; when acrylonitrile-butadiene-styrene (ABS) resin is used, the heating temperature is 210°C to 260°C, for example, 220°C to 250°C; and when polycarbonate (PC) is used, the heating temperature is 250°C to 320°C, for example, 260°C to 310°C. Four heaters 84 are arranged in the longitudinal direction of the barrel 82.

[0038] 3, the nozzle 85 is connected to the lower end of the barrel 82. The material transported by the screw is discharged from the nozzle 85 onto the molding table 50.

[0039] 3, the heat dissipation unit 86 is connected to the upper end of the barrel 82. The heat dissipation unit 86 dissipates some or all of the heat transferred from the heater 84 through the barrel 82 and the screw to the motor 83 and the connecting parts between the motor 83 and the screw. This prevents the motor 83 and the connecting parts between the motor 83 and the screw from being damaged by heat.

[0040] The cooling fan 87 sends relatively cool air (for example, air at room temperature (20° C.) or room temperature) around the modeling apparatus 100 to the heat dissipation section 86 to cool the heat dissipation section 86 .

[0041] As shown in FIGS. 2 and 3 , the colorant injection mechanisms 60 are attached to the outer edge of the second support plate 92. In this embodiment, five colorant injection mechanisms 60 having the same configuration are attached. Each colorant injection mechanism 60 contains colored pellets of a different color. The colorant injection mechanism 60 includes a colorant input section 61, a coloring barrel 62 to which colorant is supplied from the colorant input section 61, a screw (not shown) that rotates within the coloring barrel 62, a motor 63 that rotates the screw, a heater 64 for heating the colored pellets, and a cooling fan 65 for cooling the motor 63. The heater 64 is provided in the colorant input section 61 and the coloring barrel 62.

[0042] Colorant pellets are stored in the colorant supply unit 61. The colorant pellets are heated by a heater 64 to become liquid, and are then supplied to the colorant barrel 62. Under the control of the control unit 300, a motor 63 drives and rotates a screw, and the colorant is injected into the barrel 82 through an injection hole 82a shown in FIG. 3.

[0043] Two discharge material heating units 70 are arranged on the second support plate 92 surrounding the barrel 82, and each unit has a cooling mitigation blower 71 and a deflection device 72.

[0044] The cooling-relief blower 71 is disposed on the upper surface of the second support plate 92. A vent is provided on the upper surface of the second support plate 92 to which the cooling-relief blower 71 is attached. When a shaped object is manufactured, particularly when the kneading and discharging unit 80 is operating and material is being discharged from the nozzle 85, the cooling-relief blower 71 draws in air heated by a heater 84 provided on the outer periphery of the barrel 82 and sends it downward through the vent. For example, the temperature of the air sent in this manner is room temperature (20°C) or higher, for example, 30°C to 60°C when the heating temperature of the heater 84 is 200°C or higher.

[0045] The deflector 72 is disposed on the underside of the second support plate 92 so as to face the cooling mitigation blower 71 across the ventilation hole. The deflector 72 is a passage or deflector plate that deflects the air sent from the ventilation hole toward the tip of the nozzle 85.

[0046] (Effects of this embodiment) According to the present embodiment, when manufacturing a model, the cooling mitigation blower 71 sends air heated by the heater 84 provided on the outer periphery of the barrel 82 through the vent to the deflection device 72, and the deflection device 72 then applies this warm air to the material being discharged from the nozzle 85. This slows down the cooling rate of the material being discharged from the tip of the nozzle 85, thereby suppressing the effects of shrinkage of the discharged material. Therefore, according to the present invention, materials with high viscosity or low melt flow rate that could not be used as modeling materials in the past can be used as modeling materials.

[0047] Conventionally, the cooling rate of the discharged material has been reduced by controlling the temperature (bed temperature) of the modeling table 50 to a temperature higher than the ambient temperature of the modeling apparatus 100 (e.g., normal temperature (20°C) or room temperature), for example, 60°C to 120°C, depending on the material. However, since resin materials generally have poor thermal conductivity and little heat transfer in the Z direction, this method has not been able to sufficiently suppress the effects of material shrinkage, such as thermal stress, at the upper part of the object when manufacturing a tall model. According to the present invention, hot air is applied to the material discharged from the nozzle 85, so the effects of material shrinkage at the upper part of the object can be suppressed even when manufacturing a tall object.

[0048] In addition, conventionally, attempts have been made to suppress shrinkage of the discharged material by raising the environmental temperature, for example, room temperature itself, but this method requires a large amount of heat to maintain the environmental temperature, resulting in high energy costs. According to the present invention, hot air utilizing exhaust heat is applied locally to the material discharged from the nozzle 85, so additional energy costs can be kept low.

[0049] This invention is not limited to the above embodiment, and various modifications and applications are possible. In the above embodiment, two discharge material heating units 70 are provided, but one, three or more may be provided. Furthermore, if the direction of the cooling mitigation blower 71 can be appropriately adjusted so that the cooling mitigation blower 71 can directly blow hot air onto the tip of the nozzle 85, the deflection device 72 may be omitted.

[0050] In the above embodiment, the heat source of the material heating unit 70 is air heated by the heater 84 provided on the outer periphery of the barrel 82. However, other heat sources, such as the heater 64 of the colorant injection mechanism 60, the motor 83 of the kneading and discharging unit 80, and / or the motor 63 of the colorant injection mechanism 60, may be used in addition to or instead of this. In this case, an additional cooling-relief blower 71 and / or a deflector 72 may be provided along the path from the heat source to the nozzle 85 to transport the warm air from the heat source to the nozzle 85. In addition, to suppress diffusion of the heated air between the heat source and the nozzle 85, a closed, e.g., airtight, ventilation path, such as a ventilation pipe, for transporting the warm air may be provided along all or part of the path from the heat source to the nozzle 85.

[0051] Furthermore, in the above embodiment, the fused deposition modeling method in which pellets are melted has been described as a modeling apparatus, but the present invention can also be applied to a filament-type modeling apparatus.

[0052] Furthermore, in the above embodiment, the modeling apparatus 100, particularly the first print head 1A, the second print head 1B, and the modeling table 50, are arranged in an open environment, but they may also be arranged in a furnace at a high temperature, for example, 60°C to 120°C. Even in this case, the temperature of the hot air sent from the discharged material heating unit 70 is lower than the melting temperature of the material, but higher than the ambient temperature (for example, 60°C to 120°C), so it is possible to suppress the effects of shrinkage of the discharged material.

[0053] In addition, in the above embodiment, in order to suppress the effects of shrinkage of the ejected material, the first print head 1A and the second print head 1B are provided with an ejected material heating unit 70 that heats the material immediately after ejection. In addition to this, or instead of this, the modeling table 50 may be provided with an object cooling unit 75 that cools the material immediately after stacking.

[0054] The object cooling units 75 are arranged one on each end of the forming table 50, and each includes a cooling fan 76 and an air outlet 77.

[0055] The cooling fan 76 is disposed on the upper surface of the air outlet 77. When manufacturing a molded object, particularly when material is being stacked on the molding table 50, the cooling fan 76 draws in ambient air and sends it onto the molding table 50 via the air outlet 77. For example, the temperature of the air sent in this manner is ambient temperature (for example, room temperature (20°C) or room temperature when the molding table 50 is placed in an open area, or 60 to 120°C when the molding table 50 is placed inside a furnace), which is lower than the melting temperature of the material.

[0056] The air outlets 77 are arranged on both ends of the modeling table 50 so that the openings for blowing out air face each other. The width of the air outlets 77 is approximately the same as the width of the modeling table 50. For example, air blown out from the air outlets 77 in the direction indicated by the white arrows in Figure 4 collides on the modeling table 50, forming an ascending air current above the modeling table 50.

[0057] In the past, particularly when the forming table 50 was placed in a furnace, there was a risk that the object M being formed would be deformed (for example, sagging) because additional material was layered on top of the object M before it had completely solidified. According to this modified example, when manufacturing a molded object, the cooling blower 76 sends air at a temperature lower than the melting temperature of the material to the object M being formed on the forming table 50 via the air outlet 77. This promotes cooling of the object M being formed, so that the object M being formed is in a harder state when additional material is layered on top of it, making the object M being formed less likely to deform (for example, less likely to sag).

[0058] Furthermore, in this modified example, the air sent out from the air outlet 77 collides on the modeling table 50 and forms an ascending air current, so even if the height of the model M being modeled is higher than the air outlet 77, the air sent out from the air outlet 77 reaches the top surface of the model being modeled, thereby promoting cooling there.

[0059] The number of object cooling units 75 is arbitrary, and may be one, three, or more. As long as air can be sent to the object M being modeled on the modeling table 50, the object cooling units 75 may be arranged arbitrarily on the modeling table 50, and the object cooling units 75 do not have to be arranged on the modeling table 50. For example, the air outlets 77 do not have to be arranged so that the openings from which the air is sent face each other in order to form an ascending air current. As long as air can be sent to the object M being modeled on the modeling table 50, the width of the air outlets 77 is arbitrary. Furthermore, as long as air can be sent to the object M being modeled on the modeling table 50 by the cooling fan 76 by appropriately adjusting the orientation of the object cooling units 75, the air outlets 77 may be omitted.

[0060] Any means may be used to form an updraft above the modeling table 50. For example, instead of arranging the two air outlets 77 so that the openings from which the air is discharged face each other, two or more air outlets 77 may be arranged so that the air discharged from the openings collides with each other on the modeling table 50. Furthermore, instead of or in addition to forming an updraft above the modeling table 50, the model cooling unit 75 may be moved up and down by a height adjustment mechanism such as a robot arm or an electric slide mechanism depending on the height of the model being modeled.

[0061] In particular, by using the discharged material heating unit 70 and the model cooling unit 75 in combination, it is possible to suitably control the cooling rate of the material as it is discharged from the nozzle 85 and layered on the modeling table 50. This makes it possible to suppress both the effects of material shrinkage and deformation of the model.

[0062] The features described in the above-described embodiments and modifications can be combined in any manner unless they are inconsistent. [Explanation of symbols]

[0063] 1A First print head 1B Second print head 10 Bottom housing unit 20 Side housing unit 30 Upper beam unit 40 Upper housing unit 41 Frame section 50 Modeling stand 51,52 Reinforcement member 60 Colorant injection mechanism 61 Colorant input section 62 Coloring Barrel 63,83 motor 64,84 heater 65,87 Cooling blower 70 Discharge material heating unit 71 Cooling relief blower 72 Deflector 75 Model cooling unit 76 Cooling blower 77 Ventilation vent 80 Mixing and discharging unit 81 Material input section 82 barrels 82a injection hole 85 nozzles 86 Heat radiation part 90 Support Unit 91 First support plate 92 Second support plate 93 Connecting column 96 nozzles 100 Modeling equipment 200 Lifting mechanism 300 control section 400 Printhead drive mechanism 410 First Print Head Drive Mechanism 420 Second print head drive mechanism M Modeled object

Claims

1. a barrel into which material for molding is supplied; a heater that heats the material supplied into the barrel; a nozzle for discharging the heated and melted material; a blower that sends the air heated by the heater to the tip of the nozzle, Modeling equipment.

2. A deflector is provided to deflect the airflow sent from the blower.

10. The apparatus of claim 1.

3. a heat source other than the heater, further comprising an additional blower that sends the air heated by the heat source to the tip of the nozzle; 10. The apparatus of claim 1.

4. an air passage for suppressing diffusion of the air heated by the heater is provided in at least a part of the path from the heater to the tip of the nozzle; 10. The apparatus of claim 1.

5. a blower that blows air at a temperature lower than the melting temperature of the material for modeling to the object being modeled on the modeling table; Modeling equipment.

Images