Three-dimensional modeling device

Abstract

Provided is a technique capable of suppressing waste material adhering to a cleaning member from adhering to a nozzle again. The three-dimensional molding apparatus includes: a nozzle having a discharge port for discharging a molding material toward a stage; a discharge control mechanism that is provided in a flow path through which the molding material flows, and that controls the amount of the molding material supplied to the nozzle by changing the opening degree of the flow path; a suction / discharge unit that performs a suction operation for sucking the molding material in the flow path into a branch flow path connected to the flow path between the discharge control mechanism and the discharge port, and a discharge operation for discharging the molding material sucked into the branch flow path to the flow path; and a control unit that, after controlling the discharge control mechanism to stop supplying the molding material to the nozzle in a state in which the molding material is discharged from the nozzle, performs a cleaning process in which the control unit performs a suction operation by controlling the suction / discharge unit to discharge the molding material from the nozzle. At least a portion of the molding material in the nozzle is discharged to a non-molding region where the three-dimensional molding object is not molded.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a three-dimensional modeling apparatus. BACKGROUND

[0002] Patent Document 1 discloses a three-dimensional modeling apparatus provided with an end portion cleaning assembly having a wobble plate and a brush. In the three-dimensional modeling apparatus, cleaning of an extrusion head is performed by bringing the extrusion head into contact with the wobble plate and the brush.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-530326

[0004] In the case where the front end of a nozzle provided in a three-dimensional modeling apparatus is cleaned using a cleaning member such as a wobble plate or a brush, waste material adhering to the cleaning member can be reattached to the nozzle. SUMMARY

[0005] According to a first aspect of the present disclosure, a three-dimensional modeling apparatus is provided. The three-dimensional modeling apparatus is provided with: a nozzle having a discharge port that discharges a modeling material toward a stage that models a three-dimensional modeled object; a discharge control mechanism that is provided in a flow path through which the modeling material flows, and that controls the amount of supply of the modeling material to the nozzle by changing the opening degree of the flow path; a suction and delivery portion that performs a suction operation of suctioning the modeling material in the flow path into a branch flow path connected to the flow path between the discharge control mechanism and the discharge port, and a delivery operation of delivering the modeling material suctioned into the branch flow path to the flow path; and a control portion that, after the discharge control mechanism is controlled to stop the supply of the modeling material to the nozzle in a state where the modeling material is discharged from the nozzle, performs a cleaning process in which the control portion controls the suction and delivery portion to perform the suction operation, thereby discharging at least a part of the modeling material in the nozzle to a non-modeling region where the three-dimensional modeled object is not modeled. BRIEF DESCRIPTION OF DRAWINGS

[0006] Figure 1 is an explanatory diagram showing the schematic structure of a three-dimensional modeling apparatus.

[0007] Figure 2 is an explanatory diagram showing the schematic structure of a three-dimensional modeling apparatus.

[0008] Figure 3 is a perspective view showing the schematic structure of a screw.

[0009] Figure 4 is a schematic plan view of a cylinder.

[0010] Figure 5 is a perspective view of a cleaning mechanism.

[0011] Figure 6 is a side view of the cleaning mechanism.

[0012] Figure 7 is a perspective view of the cleaning section.

[0013] Figure 8 is a perspective view of the cleaning section.

[0014] Figure 9 is an explanatory view showing a case where the bottom surface of the housing section becomes an open state.

[0015] Figure 10 is an explanatory view showing a case where the waste material falls to the recovery section.

[0016] Figure 11 is a flowchart of the material discharge processing performed by the control section.

[0017] Figure 12 is a first explanatory view showing the action state of the ejection section.

[0018] Figure 13 is a perspective view of the ejection control mechanism.

[0019] Figure 14 is an image taken of the state where the modeling material is ejected.

[0020] Figure 15 is a second explanatory view showing the action state of the ejection section.

[0021] Figure 16 is an image taken of the state where the modeling material is ejected.

[0022] Figure 17 is an image taken of the ejection state of the modeling material.

[0023] Figure 18 is a third explanatory view showing the action state of the ejection section.

[0024] Figure 19 is an image taken of the state where the modeling material is sucked.

[0025] Figure 20 is an image taken of the state where the modeling material is sucked.

[0026] Figure 21 is an explanatory view showing the state inside the nozzle.

[0027] Figure 22 is a view showing an example of the modeling material.

[0028] BRIEF DESCRIPTION OF THE DRAWINGS

[0029] 10: head; 10a: first head; 10b: second head; 11: material supply section; 11a: first material supply section; 11b: second material supply section; 12: plasticizing section; 12a: first plasticizing section; 12b: second plasticizing section; 13: ejection section; 13a: first ejection section; 13b: second ejection section; 15: communication path; 20: stage; 21: molding surface; 25: position changing section; 30: stage moving section; 31: first electric actuator; 32: second electric actuator; 33: third electric actuator; 40: heating section; 41: movable section; 42: opening; 50: head lifting mechanism; 57: cross hole; 60: cleaning mechanism; 60a: first cleaning mechanism; 60b: second cleaning mechanism; 70: control section; 71: CPU; 72: storage device; 73: drive shaft; 75: recess; 77: coupling section; 80: arm section; 81: suspension member; 100: three-dimensional molding apparatus; 101: first drive section; 102: second drive section; 110: screw; 111: groove forming surface; 112: central section; 113: groove; 114: material inlet; 115: ridge section; 120: screw housing; 130: drive motor; 140: barrel; 141: opposite surface; 142: communication hole; 143: guide groove; 144: plasticizing heater; 151: nozzle; 151a: first nozzle; 151b: second nozzle; 152: ejection outlet; 152a: first ejection outlet; 152b: second ejection outlet; 153: flow passage; 154: ejection control mechanism; 156: suction and delivery section; 157: branch flow passage; 158: plunger; 210: cleaning moving section; 210a: first cleaning moving section; 210b: second cleaning moving section; 211: guide rail; 212: drive belt; 213: first pulley; 214: second pulley; 215: belt drive section; 220: cleaning section; 220a: first cleaning section; 220b: second cleaning section; 222: housing section; 224: slide rail; 225: linking section; 226: main body; 227: bottom surface; 228: sliding member; 229: spring; 230: recovery section; 230a: first recovery section; 230b: second recovery section; 241: contact member; 242: fixing member; 243: guide section; 244: guide support section. DETAILED DESCRIPTION

[0030] A. First Embodiment

[0031] Figure 1 and Figure 2 is an explanatory view showing the outline structure of the three-dimensional molding apparatus 100 in the first embodiment. Figure 1 and Figure 2The arrows indicating the X, Y, and Z directions that are orthogonal to each other are shown in FIG. 1. The X and Y directions are directions parallel to a horizontal plane, and the Z direction is a direction along a vertical upward direction. In other drawings, the directions of the illustrations of the arrows indicating the X, Y, and Z directions are also the same as Figure 1 and Figure 2 are appropriately illustrated. In the following description, in the case of determining the orientation of the direction, the direction indicated by the arrow in each drawing is set to "+" and the opposite direction thereof is set to "-" on the direction mark with the plus and minus signs. Hereinafter, the +Z direction is referred to as "up" and the -Z direction is also referred to as "down".

[0032] The three-dimensional modeling apparatus 100 of the present embodiment is an apparatus that models a modeled object by a material extrusion method. The three-dimensional modeling apparatus 100 is provided with a head 10 having a nozzle 151, a stage 20, a position changing section 25, a heating section 40, a head lifting mechanism 50, a cleaning mechanism 60 having a cleaning section 220, and a control section 70. Note that, in Figure 2 , the head lifting mechanism 50 and the cleaning mechanism 60 are omitted.

[0033] The control section 70 is a control apparatus that controls the operation of the entire three-dimensional modeling apparatus 100. As shown in Figure 2 , the control section 70 is composed of a computer provided with a CPU 71, a storage device 72, and an input / output interface that performs input and output of signals with the outside. The control section 70 functions to execute a modeling process for modeling a three-dimensional modeled object and a material discharge process described later by the CPU 71 executing a program read into a main storage device. Note that, in other embodiments, instead of being composed of a computer, the control section 70 can be realized by a configuration in which a plurality of circuits for realizing at least a part of each function are combined.

[0034] In the modeling process, the control section 70 models a three-dimensional modeled object in accordance with modeling data for modeling the three-dimensional modeled object. The modeling data includes: path information indicating a movement path of the nozzle 151 for each layer in which the shape of the modeled object is cut into a plurality of layers; and discharge amount information indicating a discharge amount of a plasticized material in each movement path.

[0035] Figure 1 and Figure 2 The head 10 shown in

[0036] The three-dimensional modeling device 100 has the first head 10a and the second head 10b as the head 10. The first head 10a has the first material supply part 11a as the material supply part 11, has the first plasticizing part 12a as the plasticizing part 12, and has the first ejection part 13a as the ejection part 13. The second head 10b has the second material supply part 11b as the material supply part 11, has the second plasticizing part 12b as the plasticizing part 12, and has the second ejection part 13b as the ejection part 13. The first head 10a and the second head 10b are arranged in the X direction in a manner that the positions in the Y direction coincide with each other. The second head 10b is arranged on the +X direction side of the first head 10a. The structure of the first head 10a and the structure of the second head 10b are the same, and therefore, hereinafter, in the case where the two are not particularly distinguished, the two are sometimes simply referred to as the head 10. In addition, in the case where the structural components of the two are distinguished, the structural components of the first head 10a are denoted with the reference sign "a", and the structural components of the second head 10b are denoted with the reference sign "b".

[0037] The material supply part 11 supplies a material for generating a modeling material to the plasticizing part 12. The material supply part 11 is constituted by, for example, a hopper. The material supply part 11 accommodates a granular or powdered material therein. As the material, for example, a thermoplastic resin such as a polypropylene resin (PP), a polylactic acid (PLA), a polyethylene resin (PE), a polyacetal resin (POM), or the like is used. The material accommodated in the first material supply part 11a and the material accommodated in the second material supply part 11b can be respectively the same kind of material, or can be respectively different kinds of material.

[0038] A communication path 15 that connects the material supply part 11 and the plasticizing part 12 is provided below the material supply part 11. The material supply part 11 supplies the material to the plasticizing part 12 via the communication path 15.

[0039] The plasticizing part 12 plasticizes at least a part of the material supplied from the material supply part 11, generates a paste-like modeling material having fluidity, and guides the modeling material to the ejection part 13. "Plasticizing" is a concept including melting, and refers to a change from a solid to a state having fluidity. Specifically, in the case of a material that undergoes a glass transition, plasticizing refers to bringing the temperature of the material to be equal to or higher than the glass transition temperature. In the case of a material that does not undergo a glass transition, plasticizing refers to bringing the temperature of the material to be equal to or higher than the melting point.

[0040] The plasticizing part 12 has a screw 110, a screw case 120, a drive motor 130, and a cylinder 140.

[0041] The screw 110 is housed in a screw case 120. The upper surface side of the screw 110 is coupled to a drive motor 130. The screw 110 is rotated in the screw case 120 by a rotational drive force generated by the drive motor 130. The axial direction of a screw rotation axis Rx, which is the rotational axis of the screw 110, is the Z direction. The rotational speed of the screw 110 is controlled by the control section 70 controlling the rotational speed of the drive motor 130. Note that the screw 110 can also be driven by the drive motor 130 via a speed reducer. The screw 110 is also referred to as a rotor or a flat screw.

[0042] A cylinder 140 is provided on the -Z direction side of the screw 110. An opposing surface 141, which is the upper surface of the cylinder 140, opposes the groove formation surface 111, which is the lower surface of the screw 110. A communication hole 142, which communicates with the flow passage 153 of the discharge section 13, is formed in the center of the cylinder 140. A plasticizing heater 144 is provided inside the cylinder 140. The temperature of the plasticizing heater 144 is controlled by the control section 70.

[0043] Figure 3 is a perspective view showing the general structure of the screw 110. The screw 110 has a substantially cylindrical shape in which the length in the direction of the screw rotation axis Rx is smaller than the length in the direction perpendicular to the screw rotation axis Rx. A spiral groove 113 is formed on the groove formation surface 111 with the center portion 112 as the center. The groove 113 communicates with a material feed port 114 formed in the side surface of the screw 110. The material fed from the material supply section 11 is fed to the groove 113 through the material feed port 114. The groove 113 is formed by being partitioned by a ridge portion 115. Figure 3 An example in which three grooves 113 are formed is shown in FIG. 12B, but the number of grooves 113 can be one or more than two. Note that the groove 113 is not limited to a spiral shape, and can be a helical shape or an involute curve shape, or a shape that extends in a manner that traces an arc from the center portion 112 toward the outer periphery.

[0044] Figure 4 is a general plan view of the cylinder 140. A plurality of guide grooves 143 are formed around the communication hole 142 on the opposing surface 141. Each guide groove 143 has one end connected to the communication hole 142 and extends in a spiral shape from the communication hole 142 toward the outer periphery of the opposing surface 141. Note that one end of the guide groove 143 can not be connected to the communication hole 142. Also, the guide groove 143 can not be formed on the cylinder 140.

[0045] The material supplied to the groove 113 of the screw 110 is plasticized while flowing in the groove 113 by the rotation of the screw 110 and the heat of the plasticizing heater 144, and is guided toward the central portion 112 of the screw 110 as a modeling material. The paste-like modeling material exhibiting fluidity that flows into the central portion 112 is supplied to the ejection portion 13 via the communication hole 142. Note that in the plasticizing portion 12, all kinds of substances constituting the modeling material can also not be plasticized. The modeling material only needs to be converted into a state having fluidity as a whole by plasticizing at least one kind of substance among the substances constituting the modeling material.

[0046] The ejection portion 13 ejects the modeling material. The ejection portion 13 includes a nozzle 151, a flow path 153, an ejection control mechanism 154, and a suction delivery portion 156.

[0047] The nozzle 151 is connected to the communication hole 142 of the barrel 140 through the flow path 153. The nozzle 151 ejects the modeling material generated in the plasticizing portion 12 toward the object table 20 from a ejection port 152 formed in a tip portion tp of the nozzle 151. More specifically, the first nozzle 151a ejects the modeling material from a first ejection port 152a formed in a first tip portion tpi. The second nozzle 151b ejects the modeling material from a second ejection port 152b formed in a second tip portion tp2.

[0048] The ejection control mechanism 154 is provided to the flow path 153, and controls the supply amount of the modeling material to the nozzle 151 by changing the opening degree of the flow path 153. In the present embodiment, the ejection control mechanism 154 is constituted by a valve, and changes the opening area of the flow path 153 by rotating in the flow path 153. The ejection control mechanism 154 is driven by a drive portion not shown under the control of the control portion 70. The drive portion that drives the ejection control mechanism 154 is constituted by, for example, a stepping motor. The control portion 70 can adjust the flow rate of the modeling material flowing from the plasticizing portion 12 to the nozzle 151, that is, the ejection amount of the modeling material ejected from the nozzle 151, by controlling the rotation angle of the valve. The ejection control mechanism 154 can adjust the ejection amount of the modeling material, and can control the on / off of the flow of the modeling material. Note that the shape of the valve can be a shape that adjusts the opening degree of the flow path 153 by rotating in the flow path 153, and can be, for example, a plate shape or a semispherical shape. In addition, in other embodiments, the ejection control mechanism 154 can be constituted by, for example, a piston mechanism that adjusts the opening degree of the flow path 153 by the action of a piston, or a shutter mechanism that adjusts the opening degree of the flow path 153 by the opening / closing of a shutter.

[0049] The suction and delivery section 156 is connected between the ejection control mechanism 154 and the ejection port 152 on the flow channel 153. The detailed structure of the suction and delivery section 156 will be described later. The control section 70 performs a suction operation of sucking the modeling material in the flow channel 153 and a delivery operation of delivering the sucked modeling material to the flow channel 153 by controlling the suction and delivery section 156. The control section 70 performs the suction operation when the moving speed of the nozzle 151 is decelerated, for example, and performs the delivery operation when the decelerated nozzle 151 is re-accelerated, at the time of performing the modeling process of modeling the three-dimensional model. By so doing, the control section 70 can suppress the line width variation of the modeling material at the acceleration and deceleration of the nozzle 151.

[0050] The stage 20 is disposed at a position opposite to the ejection port 152 of the nozzle 151. The three-dimensional modeler 100 models the three-dimensional model by ejecting the modeling material from the nozzle 151 to the modeling surface 21 which is the upper surface of the stage 20 and layering the modeling material. The region on the modeling surface 21 where the three-dimensional model is modeled is also referred to as a modeling region. In addition, the direction in which the modeling material is layered on the modeling surface 21 is also referred to as a layering direction.

[0051] The position changing section 25 changes the relative positions of the ejection section 13, the stage 20, and the cleaning section 220. As shown in FIG. 1, the position changing section 25 in the present embodiment has a stage moving section 30 and a head lifting mechanism 50. Figure 1

[0052] The stage moving section 30 changes the relative positions of the ejection section 13 and the stage 20. The stage moving section 30 is constituted by a first electric actuator 31 which moves the stage 20 in the X direction, a second electric actuator 32 which moves the stage 20 and the first electric actuator 31 in the Y direction, and a third electric actuator 33 which moves the head 10 in the Z direction. The third electric actuator 33 moves the first head 10a, the second head 10b, and the cleaning section 220 in the Z direction by moving a plate-shaped movable section 41 on which the first head 10a, the second head 10b, and the cleaning section 220 are fixed in the Z direction. The first electric actuator 31, the second electric actuator 32, and the third electric actuator 33 are driven under the control of the control section 70. Note that in the present embodiment, the third electric actuator 33 and the movable section 41 are omitted. Figure 2

[0053] ​​In other embodiments, the stage moving unit 30 may, for example, move the stage 20 in the Z direction and move the first head 10a and the second head 10b in the X and Y directions. Alternatively, the stage moving unit 30 may move the stage 20 in the X, Y, and Z directions without moving the first head 10a and the second head 10b. Alternatively, the stage moving unit 30 may move the first head 10a and the second head 10b in the X, Y, and Z directions without moving the stage 20.

[0054] The head lifting mechanism 50 moves the head 10 in the Z direction relative to the cleaning section 220. It should be noted that the head 10 is moved by the head lifting mechanism 50, so that in addition to the relative position of the ejection section 13 and the cleaning section 220 in the Z direction, the relative position of the ejection section 13 and the stage 20 in the Z direction is also changed. In the three-dimensional modeling device 100, two head lifting mechanisms 50 are provided corresponding to the first head 10a and the second head 10b. In the present embodiment, one head lifting mechanism 50 moves the first head 10a in the Z direction, and the other head lifting mechanism 50 moves the second head 10b in the Z direction. Each head lifting mechanism 50 is fixed to the movable part 41, and moves in the Z direction together with the head 10 and the cleaning mechanism 60 through the third electric actuator 33. Each head lifting mechanism 50 is configured as an electric actuator, for example, and is driven individually under the control of the control section 70. It should be noted that in Figure 2 In the figure, the head lifting mechanism 50 is omitted.

[0055] The heating unit 40 heats the modeling material stacked on the stage 20. The heating unit 40 is sheet-shaped and includes a heater. Two arms 80 extending in the Y direction are fixed to the movable unit 41. The heating unit 40 is supported opposite the modeling surface 21 by being suspended from the two arms 80. In other words, the heating unit 40 is fixed to the movable unit 41 via the two arms 80. The heating unit 40, together with the head 10 fixed to the movable unit 41, moves in the Z direction via the third electric actuator 33. Therefore, the heating unit 40, together with the first head 10a and the second head 10b, changes its relative position to the stage 20.

[0056] like Figure 2 As shown, the heating portion 40 is provided with an opening 42 that passes through the heating portion 40 along the Z direction. More specifically, the heating portion 40 is provided with two openings 42 corresponding to the first nozzle 151a and the second nozzle 151b.

[0057] In the present embodiment, the first nozzle 151a and the second nozzle 151b are each configured to be switchable between a modeling state and a retreat state by the head lifting mechanism 50. The modeling state refers to a state in which the nozzle outlet 152 is disposed between the heating section 40 and the stage 20 in the Z direction. In the modeling state, at least a portion of the nozzle 151 is disposed within the opening 42. The nozzle 151 assumes the modeling state at least at the time of modeling. The time of modeling refers to a timing at which the modeling material is ejected toward the modeling region in order to model the modeling layer. In Figure 1 and Figure 2 In the present embodiment, the first nozzle 151a and the second nozzle 151b are each configured to be switchable between a modeling state and a retreat state by the head lifting mechanism 50. The modeling state refers to a state in which the nozzle outlet 152 is disposed between the heating section 40 and the stage 20 in the Z direction. In the modeling state, at least a portion of the nozzle 151 is disposed within the opening 42. The nozzle 151 assumes the modeling state at least at the time of modeling. The time of modeling refers to a timing at which the modeling material is ejected toward the modeling region in order to model the modeling layer. In

[0058] Figure 5 is a perspective view of the cleaning mechanism 60. Figure 6 is a side view of the cleaning mechanism 60. In the present embodiment, the cleaning mechanism 60 is mounted to the arm section 80. The heating section 40 is suspended from the arm section 80 by a suspension member 81. Therefore, as shown in Figure 6 , the movable section 41 to which the arm section 80 is fixed is driven by the third electric actuator 33, so that the cleaning mechanism 60 and the heating section 40 are moved in the Z direction.

[0059] The cleaning mechanism 60 is a mechanism for cleaning the nozzle 151. As Figure 5As shown, the cleaning mechanism 60 has a cleaning moving section 210 and a cleaning section 220. In the present embodiment, the cleaning mechanism 60 has a first cleaning mechanism 60a and a second cleaning mechanism 60b. The first cleaning mechanism 60a has the first cleaning moving section 210a as the cleaning moving section 210 and has the first cleaning section 220a as the cleaning section 220. The second cleaning mechanism 60b has the second cleaning moving section 210b as the cleaning moving section 210 and has the second cleaning section 220b as the cleaning section 220. The first cleaning mechanism 60a performs cleaning of the first nozzle 151a, and the second cleaning mechanism 60b performs cleaning of the second nozzle 151b. A recovery section 230 for recovering waste discharged from the nozzles 151 by the cleaning mechanism 60 is arranged below the cleaning section 220. The recovery section 230 has a first recovery section 230a and a second recovery section 230b. The first recovery section 230a is arranged below the first cleaning section 220a, and the second recovery section 230b is arranged below the second cleaning section 220b. The first cleaning mechanism 60a and the second cleaning mechanism 60b are identical in structure. In the case of distinguishing the structural components of the two, the structural components of the first cleaning mechanism 60a are denoted with the reference numeral "a", and the structural components of the second cleaning mechanism 60b are denoted with the reference numeral "b".

[0060] The cleaning moving section 210 relatively moves the cleaning section 220 with respect to the nozzles 151. The cleaning moving section 210 is also part of the position changing section 25. The cleaning moving section 210 is fixed to the arm section 80. The cleaning moving section 210 has a drive belt 212, a first pulley 213, a second pulley 214, and a belt drive section 215. The first pulley 213 is arranged at the end of the arm section 80 on the -Y direction side. The second pulley 214 is arranged at the end of the arm section 80 on the +Y direction side. The drive belt 212 is wound between the first pulley 213 and the second pulley 214. The belt drive section 215 drives the drive belt 212 by rotating the second pulley 214. The belt drive section 215 is constituted, for example, by an electric motor and is controlled by the control section 70.

[0061] The cleaning section 220 is linked to the drive belt 212 via a linking section 225. The linking section 225 is configured to be movable in the Y direction along a guide rail 211 mounted to the arm section 80. Therefore, by the drive belt 212 being driven by the belt drive section 215, the cleaning section 220 moves in the Y direction along the guide rail 211. By being thus configured, the cleaning section 220 is relatively moved with respect to the nozzles 151 by the cleaning moving section 210.

[0062] Figure 7 and Figure 8 is a perspective view of the cleaning section 220. Figure 7 and Figure 8The second cleaning section 220b in the cleaning section 220 is shown in FIG. 12. The second cleaning section 220b and the first cleaning section 220a are symmetrical configurations with respect to the Y axis. The cleaning section 220 is provided with a housing section 222.

[0063] The housing section 222 has a cylindrical main body 226 and a bottom surface 227 disposed at the bottom of the main body 226. The main body 226 is attached to the connecting section 225. The housing section 222 houses the waste material discharged from the nozzle 151 by the material discharge processing described later.

[0064] The bottom surface 227 of the housing section 222 is configured to be openable and closable. The main body 226 and the bottom surface 227 constituting the housing section 222 are relatively slidable in the Y direction. The bottom surface 227 is opened and closed by a sliding member 228 attached to the main body 226 moving in the Y direction along a slide rail 224 attached to the bottom surface 227. A spring 229 is disposed between the end portion of the main body 226 in the -Y direction and the end portion of the bottom surface 227 in the +Y direction. The main body 226 and the bottom surface 227 are generally pulled to each other by the spring 229, so that the bottom surface 227 is located at the bottom of the main body 226 as shown in FIG. 12, and the bottom surface 227 becomes a closed state. In contrast, when the main body 226 and the bottom surface 227 are moved apart from each other, the spring 229 is stretched, and the bottom surface 227 is relatively moved in the +Y direction with respect to the main body 226, so that the bottom surface 227 does not exist at the bottom of the main body 226 as shown in FIG. 13, and the bottom surface 227 becomes an open state. Figure 7 Figure 8

[0065] Figure 9 FIG. 14 is an explanatory view showing the case where the bottom surface 227 of the housing section 222 becomes an open state. The control section 70 performs a moving operation of moving the cleaning section 220 in the horizontal direction from the position corresponding to the nozzle 151 toward the discharge position corresponding to the recovery section 230 by controlling the cleaning moving section 210 after the waste material is housed in the cleaning section 220. Figure 9 The upper portion of FIG. 15 shows a state where the cleaning section 220 is located at the position corresponding to the nozzle 151, Figure 9 The lower portion of FIG. 15 shows a state where the cleaning section 220 is located at the discharge position corresponding to the recovery section 230.

[0066] ​​When the cleaning section 220 moves toward the discharge position, the contact member 241 attached to the bottom surface 227 comes into contact with the fixing member 242 attached to the arm section 80. After the contact member 241 attached to the bottom surface 227 comes into contact with the fixing member 242 attached to the arm section 80, when the cleaning moving section 210 moves the cleaning section 220 in the -Y direction, the contact member 241 interferes with the fixing member 242, and therefore, the bottom surface 227 provided with the contact member 241 stops on the spot, and only the main body 226 of the accommodation section 222 slides toward the discharge position while pulling the spring 229. In this way, by the main body 226 sliding with respect to the bottom surface 227, the bottom surface 227 becomes in the open state, and at the discharge position, the waste falls from the accommodation section 222 to the recovery section 230.

[0067] Figure 10 is an explanatory view showing the situation in which the waste falls to the recovery section 230. As shown in Figure 5 , Figure 9 and Figure 10 , a guide section 243 for orienting the falling direction of the waste to the recovery section 230 is provided below the accommodation section 222 positioned at the discharge position. The guide section 243 is fixed to the arm section 80 via a guide support section 244. The waste falls to the recovery section 230 by sliding in the guide section 243. In the present embodiment, two guide sections 243 are fixed to the arm section 80 in correspondence with the first cleaning section 220a and the second cleaning section 220b. Therefore, it is possible to appropriately discharge the waste recovered by the first cleaning section 220a to the first recovery section 230a and to appropriately discharge the waste recovered by the second cleaning section 220b to the second recovery section 230b. Therefore, in the case where different modeling materials are respectively ejected from the first head 10a and the second head 10b, it is possible to appropriately recover the waste for each modeling material, and therefore, the recycling of the modeling materials becomes easy. Note that the recovery section 230 can also be only one.

[0068] Figure 9 The fixing member 242 shown in the drawing is installed to the guide section 243 supported in the arm section 80. That is, the guide section 243 and the fixing member 242 are fixed to the movable section 41 via the arm section 80, and not to the heating section 40. Therefore, the vibration generated when the contact member 241 provided to the bottom surface 227 of the accommodation section 222 comes into contact with the fixing member 242 installed to the guide section 243 does not directly reach the heating section 40. Thereby, it is possible to suppress the decrease in the parallelism of the heating section 40 with respect to the modeling surface 21 due to the vibration.

[0069] In the present embodiment, the fixing member 242 is constituted by a bolt. Therefore, by adjusting the mounting position of the fixing member 242 with respect to the guide portion 243 according to the tightening degree of the bolt, it is possible to adjust the contact position of the fixing member 242 with the contact member 241. Thereby, it is possible to finely adjust the position at which the waste is dropped by the cleaning portion 220.

[0070] Figure 11 is a flowchart of the material discharge processing performed by the control section 70. The material discharge processing is performed at a prescribed timing in the middle of the modeling of the three-dimensional shaped object. The timing at which the material discharge processing is performed is determined, for example, based on the elapsed time in the modeling, the number of modeled layers after the modeling, the amount of modeling material ejected from the nozzle 151. The timing at which the material discharge processing is performed can also be determined for each nozzle 151.

[0071] In step S10, the control section 70 performs position adjustment processing of adjusting the height of the nozzle 151 which is the cleaning target and the initial position of the cleaning portion 220. In the following description relating to the material discharge processing, the nozzle 151 means "the nozzle 151 which is the cleaning target" unless otherwise specified. In the position adjustment processing, the control section 70 causes the nozzle 151 to be in a retracted state by controlling the head lifting mechanism 50. The control section 70 adjusts the height of the nozzle 151 to a position at which the distance from the bottom surface 227 of the cleaning portion 220 to the nozzle 151 becomes a distance which is set in advance, in the retracted state of the nozzle 151. Hereinafter, this distance is referred to as a discharge length. The discharge length is, for example, 30 mm. The bottom surface 227 of the cleaning portion 220 corresponds to a non-modeling region in which the three-dimensional shaped object is not modeled.

[0072] In step S20, the control section 70 controls the ejection control mechanism 154 so that the modeling material is ejected from the nozzle 151. The control section 70 controls the ejection control mechanism 154 so that the modeling material is ejected until the modeling material ejected from the nozzle 151 adheres to the bottom surface 227 of the cleaning portion 220. That is, the modeling material is ejected from the nozzle 151 by the discharge length. The control section 70 preferably makes the rotation speed of the screw 110 lower than the rotation speed in the modeling processing of modeling the three-dimensional shaped object at the time of the ejection of the modeling material in step S20. By so doing, it is easy to cause the modeling material to be ejected straight downward from the nozzle 151, and it is easy to discharge the modeling material from the nozzle 151 in the cleaning processing described later.

[0073] Figure 12 is a first explanatory view showing the operation state of the ejection portion 13. Figure 13This is a perspective view of the discharge control mechanism 154. The discharge control mechanism 154 includes a cylindrical drive shaft 73 disposed within the intersecting hole 57 intersecting the flow channel 153. The drive shaft 73 is rotatable about the central axis AX1. A recess 75 is formed as a portion of the drive shaft 73, specifically, a valve. The recess 75 is mounted in a rotatable position within the flow channel 153. A coupling 77 is provided at the base end of the drive shaft 73. The coupling 77 is connected to the first drive unit 101, which rotationally drives the drive shaft 73.

[0074] The suction and delivery section 156 is composed of a branch channel 157 and a plunger 158 arranged in the branch channel 157. The branch channel 157 is connected to the channel 153 between the ejection control mechanism 154 and the ejection port 152. The branch channel 157 is also called a cylinder or a sleeve. The plunger 158 is driven by the control unit 70 controlling the second drive unit 102. The control unit 70 controls the second drive unit 102 to move the plunger 158 in the direction toward the channel 153 and the direction away from the channel 153 along the translation axis AX2. The second drive unit 102 is composed of, for example, a stepping motor, a gear rack mechanism that converts the rotational force of the stepping motor into the translational motion of the plunger 158, and the like.

[0075] In the above step S20, Figure 12 As shown, the control unit 70 controls the rotation of the drive shaft 73 so that a perpendicular line to the bottom surface of the recessed portion 75 of the ejection control mechanism 154 intersects the direction in which the flow channel 153 extends, thereby causing the molding material to flow into the flow channel 153 and be ejected from the nozzle 151. Furthermore, the control unit 70 controls the position of the plunger 158 so that the tip of the plunger 158 is slightly away from the flow channel 153. In this embodiment, in step S20, the control unit 70 sets the tip of the plunger 158 to a state where it is retracted 2 to 3 mm from the flow channel 153 into the branch flow channel.

[0076] Figure 14 This image captures the modeling material being ejected from nozzle 151 in step S20. The modeling material ejected from nozzle 151 has a diameter larger than the diameter of nozzle 151 due to the Balas effect. The Balas effect is a phenomenon in which, when a viscoelastic fluid flows through a capillary, the diameter of the flowing fluid becomes larger than the inner diameter of the capillary near the capillary outlet as the fluid attempts to exit the capillary.

[0077] When the molding material is ejected from the nozzle 151, the control unit 70 Figure 11 In step S30, the ejection control mechanism 154 is controlled to stop supplying the molding material to the nozzle 151. Then, after stopping supplying the molding material to the nozzle 151, the control unit 70 performs a cleaning process. The cleaning process includes a feeding operation in step S40 and a suction operation in step S50.

[0078] Figure 15 is a second explanatory view showing the state of operation of the ejection section 13. In the above step S30, as shown in Figure 15 , the control section 70 stops the supply of the modeling material to the nozzle 151 by controlling the rotation of the drive shaft 73 in such a manner that the perpendicular line of the bottom surface of the recess 75 of the ejection control mechanism 154 coincides with the direction in which the flow passage 153 extends. Then, the control section 70 moves the plunger 158 in the direction toward the flow passage 153 by performing the feeding operation in step S40. In the present embodiment, the control section 70 moves the plunger 158 in the direction toward the flow passage 153 until the front end of the plunger 158 protrudes into the flow passage 153. In the present embodiment, in step S40, the control section 70 protrudes the front end of the plunger 158 by 0.5 to 1.5 mm into the flow passage 153. In the present embodiment, the modeling material is extruded from the nozzle 151 at a speed faster than that at the time of ejection in step S20, and the control section 70 controls the moving speed of the plunger 158 in such a manner.

[0079] Figure 16 is an image taken of the state in which the modeling material is ejected from the nozzle 151 in step S40. In step S40, the modeling material is extruded from the nozzle 151 at a speed faster than that at the time of ejection in step S20. Therefore, the diameter of the ejected modeling material becomes larger than that of the modeling material shown in Figure 14 .

[0080] Figure 17 is an image taken of the state of ejection of the modeling material immediately after step S40 is performed. In step S40, if the plunger 158 is protruded into the flow passage 153, then immediately thereafter, the diameter of the modeling material ejected from the nozzle 151 becomes larger as shown in Figure 16 . However, thereafter, the supply of the modeling material to the nozzle 151 is interrupted, and therefore, as shown in Figure 17 , the modeling material extends downward from the nozzle 151 by the acceleration imparted thereto by its own weight and the feeding operation of step S40, and the diameter thereof becomes thin.

[0081] Figure 18 is a third explanatory view showing the state of operation of the ejection section 13. After the feeding operation is performed in step S40 of Figure 11 , the control section 70 moves the plunger 158 in the direction away from the flow passage 153 by performing the suction operation in step S50 as shown in Figure 18 . In the present embodiment, in step S50, the control section 70 introduces the plunger 158 into the branch flow passage 157 so that the front end of the plunger 158 is separated from the flow passage 153 by 5 to 6 mm.

[0082] Figure 19and Figure 20 is an image that captures a state in which the modeling material is attracted in step S50. When the plunger 158 is moved in the direction away from the flow passage 153 by step S50, the modeling material is sucked back from the discharge port 152 into the flow passage 153. Thus, as shown in Figure 19 , an acceleration is applied to the modeling material in the vertical upward direction, and the modeling material near the nozzle 151 becomes thin. Then, finally as shown in Figure 20 , the modeling material becomes more thin, and the modeling material that is ejected from the nozzle 151 is cut off from the nozzle 151. The cut-off modeling material falls to the bottom surface 227 of the cleaning section 220, and is accommodated in the accommodation section 222 as waste. The acceleration of the plunger 158 in the ejection operation and the attraction operation is determined, for example, in such a manner that an inertial force based on the weight of the modeling material located between the nozzle 151 and the cleaning section 220 and the acceleration acting on the modeling material by the ejection operation and the attraction operation exceeds the elastic force of the modeling material.

[0083] Figure 21 is an explanatory view showing a state in the nozzle 151 after the modeling material is cut off from the nozzle 151. When the modeling material is cut off from the nozzle 151 by the attraction operation performed by the above-described step S50, a hollow portion HP in which the modeling material does not exist is generated near the front end of the nozzle 151. Therefore, according to the above-described cleaning process, the modeling material of at least a part of the nozzle 151 is discharged to the outside.

[0084] The control section 70 preferably moves the plunger 158 at a higher moving speed than the moving speed of the plunger 158 in the three-dimensional modeling process in the ejection operation in step S40 and the attraction operation in step S50. More specifically, the control section 70 preferably moves the plunger 158 at the maximum moving speed among the speeds that can be controlled. If the plunger 158 is moved at a high speed in the ejection operation, a fast acceleration can be applied to the modeling material in the vertical downward direction, and if the plunger 158 is moved at a high speed in the attraction operation, the modeling material can be more strongly introduced into the nozzle 151. Therefore, the nozzle 151 can be well cut off.

[0085] In step S60 of Figure 11 , the control section 70 moves the cleaning section 220 in which the waste is accommodated toward the discharge position as shown in Figure 9 , and discharges the waste to the recovery section 230. Note that the control section 70 can also move the cleaning section 220 reciprocally in the Y-axis direction by a prescribed distance and a prescribed number of times in place before moving the cleaning section 220 toward the discharge position. By so doing, the modeling material can be torn off from the nozzle 151 in a case where the modeling material is not completely cut off from the nozzle 151.

[0086] Figure 221 is a diagram showing examples of modeling materials used in the three-dimensional modeling apparatus 100 . Figure 22 : Shown are eight molding materials, the specific heat of each molding material, the heat capacity per unit volume of each molding material, the temperature of the nozzle 151 during the cleaning process, and the viscosity of each molding material when ejected. The temperature of the nozzle 151 during the cleaning process is equal to the temperature of the molding material during the cleaning process. Among the eight molding materials, PP and PLA were used, and the above-mentioned material discharge process was performed using a nozzle 151 with a nozzle 152 having a diameter of 0.2 mm. PP and PLA do not adhere to the vicinity of the front end of the nozzle 151 and can be well cut off from the nozzle 151. In addition, with regard to PP, even when the above-mentioned material discharge process was performed using a nozzle 151 with a nozzle 152 having a diameter of 1.0 mm, it can be well cut off from the nozzle 151. Generally, the larger the diameter of the nozzle 151, the easier it is to cut the molding material from the nozzle 151. Therefore, in order to easily cut the molding material from the nozzle 151, the diameter of the nozzle 151 is preferably 0.2 mm or larger, and the molding material preferably includes a resin having a viscosity of 229 [Pa·s] or more and 1316 [Pa·s] or less at the temperature during the cleaning process.

[0087] According to the three-dimensional modeling apparatus 100 of the first embodiment described above, by performing a feed operation and a suction operation during the cleaning process, at least a portion of the modeling material within the nozzle 151 can be discharged. Therefore, it is no longer necessary to use cleaning components such as a vibrating plate or a brush to clean the nozzle 151. As a result, waste material adhering to the cleaning components can be prevented from reattaching to the nozzle 151, thereby suppressing a decrease in the modeling accuracy of the three-dimensional object caused by waste material adhering to the nozzle 151.

[0088] Furthermore, in this embodiment, during the discharge operation of the cleaning process, the plunger 158 is moved toward the flow channel 153 until the plunger 158 protrudes into the flow channel 153. Therefore, acceleration can be effectively applied to the molding material ejected from the nozzle 151, and the molding material can be effectively cut off from the nozzle 151 during the subsequent suction operation.

[0089] In this embodiment, the cleaning process is performed after the modeling material is ejected from the ejection port 152 until it adheres to the bottom surface 227 of the cleaning portion 220. Therefore, the weight of the modeling material increases, making it easier for the modeling material to be cut from the nozzle 151.

[0090] B. Other implementation methods:

[0091] (B1) In the above embodiment, Figure 11 In the cleaning process shown, the control unit 70 performs both the delivery operation and the suction operation. However, the control unit 70 may perform only the suction operation without performing the delivery operation.

[0092] (B2) In the above-described embodiments, in the material discharge processing, the modeling material is discharged to the bottom surface 227 of the cleaning section 220. In contrast, the modeling material may, for example, also be discharged to a region on the stage 20 other than a region in which the three-dimensional modeled object is modeled. Figure 11

[0093] (B3) In the above-described embodiments, in the material discharge processing, the control section 70 ejects the modeling material until the modeling material ejected from the nozzle 151 adheres to the bottom surface 227 of the cleaning section 220. In contrast, in the material discharge processing, the control section 70 may, for example, eject the modeling material in such a manner that the modeling material ejected from the nozzle 151 does not adhere to the bottom surface 227 of the cleaning section 220.

[0094] (B4) In the above-described embodiments, in the feeding operation in step S40 of the material discharge processing, the control section 70 moves the plunger 158 until the front end of the plunger 158 protrudes into the flow channel 153. In contrast, the control section 70 may, for example, displace the range of movement of the plunger 158 in the feeding operation in step S40 so that the front end of the plunger 158 does not protrude into the flow channel 153.

[0095] (B5) In the above-described embodiments, for example, in a case where the material discharge processing is performed on a deteriorated modeling material such as a modeling material left in the flow channel 153 for a certain period in a high-temperature state, the control section 70 may, for example, eject the modeling material in a length longer than a normal discharge length in step S20 of the material discharge processing. Figure 11 The control section 70, for example, calculates the degree of deterioration of the modeling material on the basis of the temperature of the heating section 40, the left time of the modeling material, and the number of times of turning on and off of the heating section 40, and ejects the modeling material in a length longer than a normal discharge length in a case where the degree of deterioration exceeds a threshold value set in advance.

[0096] (B6) In the above-described embodiments, the nozzle 151 is cleaned without using a cleaning member such as a wobble plate or a brush. In contrast, for example, in a case where the viscosity of the modeling material is greater than a threshold value set in advance, the cleaning processing can be performed by bringing the cleaning member into contact with the nozzle 151, and in a case where the viscosity is equal to or less than the threshold value, the cleaning processing can also be performed without using the cleaning member as in the above-described embodiments.

[0097] ​(B7) The material discharge processing in the above-described embodiments can be performed not only during the molding of the three-dimensional molded article but also instead of during the molding of the three-dimensional molded article, before the start of the ejection of the initial molding material for molding the three-dimensional molded article, or after the completion of the molding of the three-dimensional molded article. In addition, the material discharge processing can be performed when the user performs a prescribed start operation on the control unit 70.

[0098] (B8) In the above-described embodiments, the three-dimensional molding apparatus 100 is provided with two heads 10. In contrast, the three-dimensional molding apparatus 100 can be provided with only one head 10 or three or more heads.

[0099] C. Other Modes

[0100] The present disclosure is not limited to the above-described embodiments and can be realized by various structures without departing from the gist thereof. For example, in order to solve part or all of the above-described technical problems or in order to achieve part or all of the above-described effects, the technical features of the embodiments corresponding to the technical features described in each of the modes below can be appropriately replaced, combined. In addition, if the technical features are not described as essential features in the present specification, they can be appropriately deleted.

[0101] (1) According to a first mode of the present disclosure, a three-dimensional molding apparatus is provided. The three-dimensional molding apparatus includes: a nozzle having a nozzle opening that ejects a molding material toward a stage that molds a three-dimensional molded article; an ejection control mechanism that is provided in a flow path through which the molding material flows, and controls the supply amount of the molding material to the nozzle by changing the opening degree of the flow path; a suction and delivery unit that performs a suction operation of suctioning the molding material in the flow path into a branch flow path connected to the flow path between the ejection control mechanism and the nozzle opening, and a delivery operation of delivering the molding material suctioned into the branch flow path to the flow path; and a control unit that, after controlling the ejection control mechanism to stop supplying the molding material to the nozzle in a state where the molding material is being ejected from the nozzle, performs a cleaning process in which the control unit controls the suction and delivery unit to perform the suction operation, thereby discharging at least part of the molding material in the nozzle to a non-molding region that does not mold the three-dimensional molded article.

[0102] According to such a mode, at least part of the molding material in the nozzle can be discharged by the suction operation of suctioning the molding material in the flow path into the branch flow path, and thus cleaning does not need to be performed using a cleaning member such as a wobble plate or a brush. Therefore, waste material attached to the cleaning member does not reattach to the nozzle.

[0103] (2) In the three-dimensional modeling apparatus of the above-described aspect, the suction and delivery section can include a plunger that moves in the branch flow path, and in the cleaning process, the control section can move the plunger in a direction away from the flow path after moving the plunger in a direction toward the flow path by the delivery operation.

[0104] (3) In the three-dimensional modeling apparatus of the above-described aspect, in the delivery operation in the cleaning process, the control section can move the plunger in a direction toward the flow path until the plunger protrudes in the flow path. According to this aspect, acceleration can be effectively applied to the modeling material ejected from the nozzle, and in the subsequent suction operation, the modeling material can be favorably cut off from the nozzle.

[0105] (4) In the three-dimensional modeling apparatus of the above-described aspect, the control section can control a moving speed of the plunger in the suction operation and the delivery operation in each of a modeling process in which the three-dimensional modeled object is modeled and the cleaning process, and the control section can make the moving speed of the plunger in the cleaning process faster than the moving speed of the plunger in the modeling process. According to this aspect, the modeling material can be favorably cut off from the nozzle.

[0106] (5) In the three-dimensional modeling apparatus of the above-described aspect, the control section can perform the cleaning process after causing the modeling material to be ejected from the nozzle until the modeling material adheres to the non-modeling region. According to this aspect, the weight of the modeling material ejected from the nozzle increases, and the modeling material becomes easier to be cut off from the nozzle.

[0107] (6) In the three-dimensional modeling apparatus of the above-described aspect, a diameter of the nozzle can be 0.2 mm or more, and the modeling material can include a resin having a viscosity of 229 [Pa·s] or more and 1316 [Pa·s] or less at a temperature at which the cleaning process is performed.

[0108] The present disclosure is not limited to the above-described aspects of the three-dimensional modeling apparatus, and can be implemented by various aspects such as a cleaning method of a nozzle, a manufacturing method of a three-dimensional modeled object, and the like.

Claims

1. A three-dimensional modeling apparatus characterized by comprising: Possessing: a nozzle having a discharge port that discharges a modeling material toward a stage that forms a three-dimensional object; a discharge control mechanism that is provided in a flow path through which the modeling material flows, and controls the amount of supply of the modeling material to the nozzle by changing the opening degree of the flow path; a suction and delivery section that performs a suction operation that suctions the modeling material in the flow path into a branch flow path that is connected to the flow path between the discharge control mechanism and the discharge port, and a delivery operation that delivers the modeling material suctioned into the branch flow path to the flow path; and a control section that, after controlling the discharge control mechanism to stop supplying the modeling material to the nozzle in a state in which the modeling material is discharged from the nozzle, performs a cleaning process, in the cleaning process, the control section discharges at least a part of the modeling material in the nozzle to a non-modeling region in which the three-dimensional object is not formed, by controlling the suction and delivery section to perform the suction operation.

2. The three-dimensional modeling apparatus according to claim 1, wherein the suction and delivery section has a plunger that moves in the branch flow path, in the cleaning process, the control section moves the plunger in a direction away from the flow path by the suction operation after moving the plunger in a direction toward the flow path by the delivery operation.

3. The three-dimensional modeling apparatus according to claim 2, wherein in the delivery operation in the cleaning process, the control section moves the plunger in the direction toward the flow path until the plunger protrudes in the flow path.

4. The three-dimensional modeling apparatus according to claim 2, wherein the control section controls the moving speed of the plunger in the suction operation and the delivery operation in each of a modeling process in which the three-dimensional object is formed and the cleaning process, the control section makes the moving speed of the plunger in the cleaning process faster than the moving speed of the plunger in the modeling process.

5. The three-dimensional modeling apparatus according to claim 1, wherein the control section performs the cleaning process after discharging the modeling material from the discharge port until the modeling material adheres to the non-modeling region.

6. The three-dimensional modeling apparatus according to claim 1, wherein the diameter of the discharge port is 0.2 mm or more, the modeling material includes a resin whose viscosity at the temperature at which the cleaning process is performed is 229 [Pa·s] or more and 1316 [Pa·s] or less.

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