Three-dimensional modeling device

Abstract

To prevent damage to respective parts of an apparatus or damage to a three-dimensional molded product previously molded on a molding face caused by a contact between a molding material remaining on the molding face and the respective parts of the apparatus.SOLUTION: A three-dimensional molding apparatus comprises: a discharging section that has a nozzle opening, and discharges a molding material from the nozzle opening; a stage that has a molding face for supporting the molding material discharged from the discharging section; a sensor section that detects the molding material supported on the molding face; and a control section that controls the discharging section to stack the molding material on the molding face and mold a three-dimensional product. The control section, prior to the start of molding of the three-dimensional molded product, executes, by controlling the sensor section, a remainder detecting step of detecting the molding material remaining on the molding face.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a three-dimensional printing apparatus. [Background technology]

[0002] Regarding a three-dimensional modeling apparatus, Patent Document 1 discloses a technology for detecting the temperature of a modeling layer during modeling and modeling an object while monitoring the modeling status. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-151933 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a three-dimensional printing device such as that described above, after the printing of a previous object is completed, printing of the next object may begin while the previous object remains on the stage, and there is a risk of damage to the previous object or the device due to contact between the previous object and the device. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided a three-dimensional modeling apparatus. The three-dimensional modeling apparatus includes a discharge unit having a nozzle opening and discharging a modeling material from the nozzle opening, a stage having a modeling surface that supports the modeling material discharged from the discharge unit, a sensor unit that detects the modeling material supported on the modeling surface, and a control unit that controls the discharge unit to stack the modeling material on the modeling surface to form a three-dimensional object. Prior to starting modeling of the three-dimensional object, the control unit controls the sensor unit to execute a remaining detection step of detecting the modeling material remaining on the modeling surface. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a first diagram showing a schematic configuration of a three-dimensional printing apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a second diagram showing a schematic configuration of the three-dimensional printing apparatus according to the first embodiment. [Diagram 3] FIG. 4 is a schematic perspective view showing the configuration of a groove forming surface side of a screw. [Figure 4] FIG. 2 is a top view showing the configuration of the side of the barrel facing the screw. [Diagram 5] FIG. 2 is a diagram illustrating a process of forming a three-dimensional object. [Figure 6] 4 is a flowchart of a three-dimensional modeling process. [Figure 7] FIG. 13 is a top view showing the sensor unit located at the start position. [Figure 8] FIG. 13 is a top view showing the sensor unit in the final position. [Figure 9] 13A and 13B are diagrams for explaining a trajectory of a detection light in the Y direction in a remaining detection process. [Figure 10] 13 is a flowchart of a remaining detection process. [Figure 11] FIG. 13 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a second embodiment. [Figure 12] FIG. 13 is a diagram showing an example of how a dimension of a three-dimensional object in the Y direction is measured. [Figure 13] FIG. 11 is a diagram showing an example of how a dimension of a three-dimensional object in the Z direction is measured. [Figure 14] FIG. 13 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] A. First embodiment: FIG. 1 is a first diagram showing a schematic configuration of a three-dimensional modeling apparatus 100 in the first embodiment. FIG. 2 is a second diagram showing a schematic configuration of a three-dimensional modeling apparatus 100 in the first embodiment. In FIG. 1 and FIG. 2, arrows along the X, Y, and Z directions perpendicular to each other are shown. The X, Y, and Z directions are directions along the X, Y, and Z axes, which are three spatial axes perpendicular to each other, and each direction includes both a direction on one side along the X, Y, and Z axes and an opposite direction. The X and Y axes are axes along a horizontal plane, and the Z axis is an axis along a vertical line. The -Z direction is a vertical direction, and the +Z direction is a direction opposite to the vertical direction. The -Z direction is also called "down" and the +Z direction is also called "up". In other figures, arrows along the X, Y, and Z directions are appropriately shown. The X, Y, and Z directions in FIG. 1 and FIG. 2 and the X, Y, and Z directions in other figures represent the same directions. In this specification, the term "orthogonal" includes the range of 90°±10°.

[0008] As shown in FIGS. 1 and 2, the three-dimensional modeling apparatus 100 includes a discharge unit 200, a stage 300, a position change unit 400, a control unit 500, a sensor unit 600, a heating unit 700, and a notification unit 800.

[0009] The discharge unit 200, under the control of the control unit 500, discharges the modeling material, which is made by melting a solid material to make it into a paste, onto the modeling stage 300, which serves as the base for a three-dimensional object. As shown in Fig. 2, the discharge unit 200 includes a material supply unit 20, which is a supply source of the material before it is converted into the modeling material, a plasticizing unit 30, which plasticizes the material to generate the modeling material, and a nozzle 61, which discharges the generated modeling material. The discharge unit 200 is sometimes called a head.

[0010] The material supply unit 20 contains materials in the form of pellets, powder, etc. In this embodiment, ABS resin formed into pellets is used as the material. The material supply unit 20 in this embodiment is configured by a hopper. A supply path 22 that connects the material supply unit 20 and the plasticizing unit 30 is provided below the material supply unit 20. The material supply unit 20 supplies the material to the plasticizing unit 30 via the supply path 22.

[0011] The plasticizing unit 30 includes a screw case 31, a drive motor 32, a screw 40, and a barrel 50. The plasticizing unit 30 plasticizes at least a part of the material supplied from the material supply unit 20, generates a pasty modeling material having fluidity, and supplies it to the nozzle 61. "Plasticization" means that heat is applied to a material having thermoplasticity to melt it. "Melting" means not only that a material having thermoplasticity is heated to a temperature above its melting point to become liquid, but also that a material having thermoplasticity is heated to a temperature above its glass transition point to soften it and develop fluidity. The screw 40 of this embodiment is a so-called flat screw, and is sometimes called a "scroll".

[0012] The screw case 31 is a housing for housing the screw 40. A barrel 50 is fixed to the lower surface of the screw case 31, and the screw 40 is housed in a space surrounded by the screw case 31 and the barrel 50. The screw 40 has a groove forming surface 42 on which a groove 45 is formed, on a surface facing the barrel 50. A drive motor 32 is fixed to the upper surface of the screw case 31. The rotating shaft of the drive motor 32 is connected to the upper surface 41 side of the screw 40. Note that the drive motor 32 does not have to be directly connected to the screw 40, and for example, the screw 40 and the drive motor 32 may be connected via a reducer. The drive motor 32 is driven under the control of the control unit 500.

[0013] The barrel 50 is disposed below the screw 40. The barrel 50 has a screw-facing surface 52 facing the groove forming surface 42 of the screw 40. The barrel 50 is provided with a communication hole 56 on the central axis RX of the screw 40, the communication hole 56 communicating with a nozzle flow path 65 of a nozzle 61 described below. The barrel 50 has a heater 58 built in at a position facing the groove 45 of the screw 40. The temperature of the heater 58 is controlled by a control unit 500.

[0014] 3 is a schematic perspective view showing the configuration of the groove forming surface 42 side of the screw 40. A central portion 47 of the groove forming surface 42 of the screw 40 is configured as a recess to which one end of the groove 45 is connected. The central portion 47 faces the communication hole 56 of the barrel 50 shown in FIG. 2. The central portion 47 intersects with the central axis RX.

[0015] The groove 45 constitutes a so-called scroll groove. The groove 45 extends from the central portion 47 in a spiral shape so as to draw an arc toward the outer periphery of the screw 40. The groove forming surface 42 is provided with a convex rib portion 46 which constitutes the side wall portion of the groove 45 and extends along each groove 45. The groove 45 continues to a material inlet 44 formed on the side surface 43 of the screw 40. This material inlet 44 is a portion which receives the material supplied through the supply path 22 of the material supply section 20. As shown in FIG. 2, in this embodiment, three grooves 45 are formed, separated by the convex rib portion 46. The number of grooves 45 is not limited to three, and may be one, or may be two or more. The groove 45 is not limited to a spiral shape, but may be a spiral shape or an involute curve shape, or may be a shape which extends from the central portion 47 to the outer periphery so as to draw an arc.

[0016] FIG. 4 is a top view showing the configuration of the screw-opposing surface 52 side of the barrel 50. As described above, a communication hole 56 is formed in the center of the screw-opposing surface 52. A plurality of guide grooves 54 are formed around the communication hole 56 in the screw-opposing surface 52. One end of each guide groove 54 is connected to the communication hole 56, and extends in a spiral shape from the communication hole 56 toward the outer periphery of the screw-opposing surface 52. Each guide groove 54 has a function of guiding the molding material to the communication hole 56. Note that one end of the guide groove 54 does not have to be connected to the communication hole 56. Also, the guide groove 54 does not have to be formed in the barrel 50.

[0017] As shown in FIG. 2, the nozzle 61 includes a nozzle flow path 65 and a tip surface 63 in which a nozzle opening 62 is provided. The nozzle flow path 65 is a flow path of the modeling material formed in the nozzle 61, and is connected to the communication hole 56 of the barrel 50 described above. The tip surface 63 is a surface constituting the tip portion of the nozzle 61 protruding in the -Z direction toward the modeling surface 311. The nozzle opening 62 is a portion in which the flow path cross section of the nozzle flow path 65 is reduced, provided at the end of the nozzle flow path 65 on the side communicating with the atmosphere. The modeling material generated by the plasticizing unit 30 is supplied to the nozzle 61 through the communication hole 56, and is discharged from the nozzle opening 62 through the nozzle flow path 65.

[0018] The stage 300 is disposed at a position facing the tip surface 63 of the nozzle 61. The stage 300 has a modeling surface 311 on which the modeling material discharged from the nozzle opening 62 of the nozzle 61 is laminated, at least in a part of the upper surface of the stage 300. The modeling surface 311 in this embodiment is configured as a rectangular surface parallel to the X direction and the Y direction. The three-dimensional modeling device 100 discharges the modeling material from the nozzle 61 toward the modeling surface 311 of the stage 300, and forms a three-dimensional object by stacking layers of the modeling material. Hereinafter, the direction in which the modeling material is laminated on the modeling surface 311 may be referred to as the stacking direction. The direction along the modeling surface 311 may be referred to as the first direction, and the direction along the modeling surface 311 and intersecting with the first direction may be referred to as the second direction. The direction perpendicular to the modeling surface 311 may be referred to as the third direction. The stacking direction, the first direction, the second direction, and the third direction each include both a direction on one side along the same axis and the opposite direction. In this embodiment, the stacking direction and the third direction are the Z direction, the first direction is the X direction, and the second direction is the Y direction.

[0019] The position changer 400 changes the relative position between the discharger 200 and the stage 300. In this embodiment, the position changer 400 changes the relative positions between the discharger 200 and the stage 300 in the X and Y directions by moving the stage 300 in the X and Y directions, and changes the relative positions between the discharger 200 and the stage 300 in the Z direction by moving the discharger 200 along the Z direction. As shown in FIG. 1, in this embodiment, the position changer 400 is composed of a first electric actuator 410 that moves the stage 300 along the X direction, a second electric actuator 420 that moves the stage 300 and the first electric actuator 410 along the Y direction, and a third electric actuator 430 that moves the discharger 200 along the Z direction. Each of the electric actuators 410 to 430 is driven under the control of the control unit 500. In other embodiments, the position change unit 400 may, for example, move the stage 300 in the Z direction and move the discharge unit 200 along the X and Y directions, or may move the stage 300 in the X, Y and Z directions without moving the discharge unit 200, or may move the discharge unit 200 in the X, Y and Z directions without moving the stage 300.

[0020] In the following, a change in the position of the discharge unit 200 relative to the stage 300 may simply be referred to as movement of the discharge unit 200. In this embodiment, for example, moving the stage 300 in the +X direction relative to the discharge unit 200 may be rephrased as moving the discharge unit 200 in the -X direction. Similarly, a change in the position of the nozzle 61, the sensor unit 600 described below, and the heating unit 700 relative to the stage 300 may simply be referred to as movement of the nozzle 61, the sensor unit 600, and the heating unit 700.

[0021] 1 and 2 detects the modeling material supported on the modeling surface 311. In this embodiment, the sensor unit 600 is configured by an optical sensor that optically detects the modeling material supported on the modeling surface 311. The sensor unit 600 has a light-emitting unit 610 that emits detection light DR and a light-receiving unit 620 that receives the detection light DR emitted from the light-emitting unit 610. The light-emitting unit 610 and the light-receiving unit 620 are electrically connected to the control unit 500 via wiring (not shown).

[0022] In this embodiment, the light emitting unit 610 is configured by a laser oscillator that emits laser light as the detection light DR. As shown in FIG. 1, the light emitting unit 610 is supported by a first support unit 601. The first support unit 601 has a first holder 602 that supports the light emitting unit 610 and a first support column 603 to which the first holder 602 is fixed. The first support column 603 is disposed in a position in the +X direction of the stage 300 so that its longitudinal direction is along the Z direction. The first holder 602 is fixed to the first support column 603 so that its position in the Z direction relative to the first support column 603 and its angle relative to the first support column 603 are adjustable. In this embodiment, the light emitting unit 610 is supported by the first support unit 601 so that the detection light DR emitted from the light emitting unit 610 travels on the modeling surface 311 along the first direction, more specifically, in the -X direction. Note that "on the printing surface 311" refers to the upper surface of the printing surface 311 and the area above the upper surface of the printing surface 311.

[0023] In this embodiment, the light receiving unit 620 is configured by a laser diode, and receives the detection light DR and converts it into an electrical signal. The light receiving unit 620 is supported by the second support unit 604 so as to face the light emitting unit 610 in the first direction, that is, the X direction. The second support unit 604 has a second holder 605 that supports the light receiving unit 620 and a second support column 606 to which the second holder 605 is fixed. The second support unit 604 is configured similarly to the first support unit 601, except that it supports the light receiving unit 620 instead of the light emitting unit 610. The second support column 606 is disposed in a position in the -X direction of the stage 300 so that its longitudinal direction is along the Z direction and so that the position of the second support column 606 in the Y direction coincides with the position of the first support column 603 in the Y direction. Therefore, in this embodiment, the light receiving unit 620 faces the light emitting unit 610 in the X direction, with the modeling surface 311 in between.

[0024] In this embodiment, the position changing unit 400 described above functions as a first moving unit that moves the sensor unit 600 along the Y direction relative to the stage 300. More specifically, the second electric actuator 420 of the position changing unit 400 moves the stage 300 along the Y direction relative to the fixed light-emitting unit 610 and light-receiving unit 620, whereby the sensor unit 600 moves along the Y direction relative to the stage 300.

[0025] 1 and 2 is a member for heating the modeling material layered on the modeling surface 311. The heating unit 700 in this embodiment is disposed on the outer periphery of the nozzle 61, and is fixed to the discharge unit 200 via the support unit 205. The support unit 205 has a rectangular plate-like outer shape, and a through-hole through which the nozzle 61 is inserted is provided in the center of the support unit 205. The heating unit 700 is disposed parallel to the modeling surface 311. The heating unit 700 moves in accordance with the discharge unit 200, which is moved by the position change unit 400.

[0026] The heating unit 700 of this embodiment is configured by a heater and is configured to be able to uniformly heat the entire area of ​​the modeling surface 311. More specifically, the area of ​​the heating unit 700 is larger than the area of ​​the modeling surface 311, and the outer periphery of the heating unit 700 is disposed outside the area in which the stage 300 moves relative to the discharge unit 200 when viewed along the Z direction. In other words, no matter how the relative positions of the heating unit 700 and the stage 300 are changed by the position change unit 400, the stage 300 is disposed inside the outer periphery of the heating unit 700 when viewed along the Z direction. The heater constituting the heating unit 700 may be, for example, a halogen heater, a nichrome wire heater, a carbon heater, or a heater that blows out hot air.

[0027] In this embodiment, the heating unit 700 and the sensor unit 600 are disposed at positions where they do not overlap each other when viewed along the Z direction. More specifically, the light emitting unit 610 is disposed at a position in the +X direction farther than the end of the heating unit 700 in the +X direction. The light receiving unit 620 is disposed at a position in the -X direction farther than the end of the heating unit 700 in the -X direction.

[0028] The notification unit 800 notifies the user of information. In this embodiment, the notification unit 800 is configured with a liquid crystal monitor connected to the control unit 500, and notifies the user of information by displaying visual information on the liquid crystal monitor. The notification unit 800 notifies, for example, the control state of the three-dimensional printing apparatus 100 as information. For example, when the discharge unit 200 and the stage 300 are installed inside a housing, the notification unit 800 may be disposed on an outer wall surface of the housing as a monitor that is visible from outside the housing.

[0029] The control unit 500 is a control device that controls the overall operation of the three-dimensional modeling apparatus 100. The control unit 500 is configured by a computer having one or more processors, a memory, and an input / output interface that inputs and outputs signals from and to the outside. The control unit 500 performs a function of, for example, executing a three-dimensional modeling process for modeling a three-dimensional object by the processor executing a program or command loaded onto the main storage device. Note that the control unit 500 may be realized by a configuration combining a plurality of circuits for realizing at least a part of each function, instead of being configured by a computer.

[0030] The control unit 500 includes a detection unit 510. The detection unit 510 in this embodiment is a functional unit that is realized by the control unit 500 executing a program. The control unit 500, which functions as the detection unit 510, executes a remaining detection process before the start of the formation of a three-dimensional object. The remaining detection process refers to a process of controlling the above-mentioned sensor unit 600 to detect the remaining modeling material that is the modeling material remaining on the modeling surface 311. The remaining modeling material detected in the remaining detection process is the modeling material that is already supported on the modeling surface 311 before the start of the formation of a three-dimensional object, and is, for example, a three-dimensional object previously modeled on the modeling surface 311, its fragments, or residual modeling material that has fallen from the discharge unit 200 or the like onto the modeling surface 311 when the previous three-dimensional object is modeled. The remaining detection process will be described in detail later. Note that in other embodiments, the detection unit 510 may be configured, for example, by a computer or the like separate from the control unit 500.

[0031] The three-dimensional modeling process refers to a process for modeling a three-dimensional object. The three-dimensional modeling process is executed by the control unit 500 when a predetermined start operation is performed by a user on an operation panel provided in the three-dimensional modeling device 100 or on a computer connected to the three-dimensional modeling device 100. The three-dimensional modeling process is sometimes simply called a modeling process. The control unit 500 starts the three-dimensional modeling process, for example, when a start command is received from a user via an input unit (not shown) or the like.

[0032] 5 is a diagram showing a schematic diagram of a three-dimensional object OB being formed by the three-dimensional modeling process. In the modeling process, the control unit 500 appropriately controls the discharge unit 200 and the position change unit 400 shown in FIG. 1 according to modeling data described later to discharge the modeling material from the nozzle opening 62 of the nozzle 61 toward the stage 300, and forms a three-dimensional object OB by stacking layers of the modeling material in the Z direction while solidifying the modeling material on the modeling surface 311. The solidification of the material refers to the loss of fluidity of the discharged plasticized material. In this embodiment, the modeling material is thermally contracted by cooling and loses plasticity, thereby solidifying.

[0033] More specifically, in the modeling process, the control unit 500 ejects the modeling material from the nozzle 61 while moving the nozzle 61 in the X direction and the Y direction as shown in FIG. 5. The modeling material ejected from the nozzle 61 is continuously deposited in the moving direction of the nozzle 61. As a result, a linear portion LP that extends linearly along the moving path of the nozzle 61 is formed. The control unit 500 repeats the above-mentioned scanning by the nozzle 61 to form a layer ML. After forming one layer ML, the control unit 500 moves the position of the nozzle 61 relative to the stage 300 in the Z direction, and further stacks layers ML on the layers ML formed so far, thereby forming a modeled object. Therefore, in the modeling process, the ejection unit 200 and the nozzle 61 are located closest to the modeling surface 311 when the first layer L1 of the three-dimensional object OB is being modeled, and then move away from the modeling surface 311 as the upper layers are modeled.

[0034] In the modeling process, the control unit 500 discharges the modeling material from the nozzle 61 while maintaining the distance between the nozzle 61 and the discharge target. The discharge target is the modeling surface 311 when the modeling material is discharged onto the modeling surface 311, and is the upper surface of the modeling material that has already been discharged when the modeling material is discharged onto the modeling material that has already been discharged. The distance between the nozzle 61 and the discharge target is sometimes called the gap Gp.

[0035] The width of the linear portion LP described above is sometimes called the line width, and the height is sometimes called the layer pitch. In the example of FIG. 5, the line width corresponds to the dimension of the linear portion LP in the Y direction, and the layer pitch corresponds to the dimension of the linear portion LP in the Z direction. The line width and layer pitch are determined by the size of the gap Gp described above and the amount of the modeling material discharged from the nozzle 61 per unit movement amount. For example, when the gap Gp is ​​small, the modeling material discharged from the nozzle 61 is pressed more against the discharge target by the nozzle 61 than when the gap Gp is ​​large, so that the layer pitch is small and the line width is large. The amount of the modeling material discharged from the nozzle 61 per unit movement amount is determined, for example, by the movement speed of the nozzle 61 and the amount of the modeling material discharged from the nozzle 61 per unit time. The amount of the modeling material discharged from the nozzle 61 per unit time is determined, for example, by the diameter of the nozzle opening 62, the flow rate of the modeling material flowing through the nozzle flow path 65, etc.

[0036] 6 is a flowchart of the three-dimensional printing process in this embodiment. In step S110, the control unit 500 acquires printing data from an external computer, a recording medium, or the like. The printing data includes printing path data representing the movement path of the nozzle 61 for each layer forming the three-dimensional object. The printing path data is associated with ejection amount data representing the ejection amount of material ejected from the nozzle 61.

[0037] In step S120, the control unit 500 executes a remaining detection process. In this embodiment, in the remaining detection process, the control unit 500 detects the remaining modeling material by moving the sensor unit 600 relatively to the stage 300 along the second direction, i.e., the Y direction, while emitting the detection light DR from the light-emitting unit 610. More specifically, in the remaining detection process, the control unit 500 executes a remaining detection process described later and detects the remaining modeling material by moving the sensor unit 600 in the -Y direction relatively to the stage 300 from the start position to the end position.

[0038] FIG. 7 is a top view showing the sensor unit 600 positioned at the start position. FIG. 8 is a top view showing the sensor unit 600 positioned at the end position. FIG. 7 and FIG. 8 show the state when the stage 300 and the sensor unit 600 are viewed from above. FIG. 7 and FIG. 8 show a remaining object RB, which is a three-dimensional object previously formed, as an example of the remaining forming material supported on the forming surface 311. As shown in FIG. 7, the start position in this embodiment is a position where the detection light DR emitted from the light-emitting unit 610 positioned at the start position overlaps with one end Eg1 in the Y direction of the forming surface 311 when viewed along the Z direction. As shown in FIG. 8, the end position in this embodiment is a position where the detection light DR emitted from the light-emitting unit 610 positioned at the end position overlaps with the other end Eg2 in the Y direction of the forming surface 311 when viewed along the Z direction. As shown in FIG. 7 and FIG. 8, the one end Eg1 is located in the -Y direction of the other end Eg2.

[0039] Fig. 9 is a diagram illustrating a trajectory Lc in the Y direction of the detection light DR in the remaining detection process. Fig. 9 shows the state of the stage 300 and the above-mentioned remaining object RB when viewed along the X direction. The trajectory Lc is traced by the light-emitting unit 610, which emits the detection light DR traveling in the -X direction, moving in the +Y direction from the start position to the end position by the position change unit 400 in the remaining detection process.

[0040] FIG. 10 is a flowchart of the remaining detection process executed in step S120 of FIG. 7 described above. In step S121, the control unit 500 controls the position change unit 400 functioning as the first moving unit to move the sensor unit 600 to the start position as shown in FIG. 7. Then, in step S122, the control unit 500 starts emitting the detection light DR from the light emitting unit 610. Next, in step S123, the control unit 500 controls the position change unit 400 to move the sensor unit 600 in the +Y direction, thereby moving the sensor unit 600 to the end position with the detection light DR emitted from the light emitting unit 610 as shown in FIG. 8 and FIG. 9. Then, in step S124, the control unit 500 stops emitting the detection light DR.

[0041] In step S125, the control unit 500 determines whether or not the remaining modeling material supported on the modeling surface 311 has been detected. In the remaining detection process, as shown in FIG. 9, during a period in which the sensor unit 600 moves from the start position to the end position while tracing a trajectory Lc with the detection light DR, the intensity of the detection light DR received by the light receiving unit 620 is smaller during a period in which the detection light DR is irradiated onto the remaining object RB than during a period in which the detection light DR is not irradiated onto the remaining object RB. On the other hand, for example, when no remaining modeling material such as the remaining object RB is located anywhere on the modeling surface 311, the intensity of the detection light DR received by the light receiving unit 620 is approximately constant during a period in which the sensor unit 600 moves from the start position to the end position. Therefore, in step S125 of FIG. 9, the control unit 500 can detect the remaining modeling material based on the detection value of the detection light DR detected by the light receiving unit 620.

[0042] More specifically, in this embodiment, in step S125, the control unit 500 determines that the remaining modeling material has been detected when the detection value of the detection light DR by the light receiving unit 620 is smaller than a predetermined reference value over a predetermined determination period. The reference value of the detection light DR may be determined based on the detection value when the detection light DR is directly received by the light receiving unit 620 without being irradiated to the remaining modeling material, or may be determined as a value small enough to suppress erroneous detection of the remaining modeling material.

[0043] The determination period is determined based on, for example, the dimensions of the forming material to be detected in the remaining detection process. The period during which the detection light DR is irradiated to the remaining object RB is determined by the dimension W in the Y direction of the remaining object RB and the moving speed of the sensor unit 600 along the Y direction, as shown in Figs. 7 to 9. Therefore, if the moving speed of the sensor unit 600 is the same, a forming material having a smaller dimension in the Y direction may be detected as the remaining forming material when the determination period is shorter. Therefore, by determining the determination period as a period during which a forming material that is small enough not to interfere with the operation of the discharge unit 200 or the like when forming a three-dimensional object OB is not detected, such a forming material can be ignored in the remaining detection process.

[0044] In addition, by changing the positions of the light-emitting unit 610 and the light-receiving unit 620 in the Z direction and changing the distance between the detection light DR and the stage 300, the lower limit of the dimension in the Z direction of the modeling material that can be detected by the remaining detection process can be changed. For example, by making the distance between the detection light DR and the stage 300 closer, a modeling material with a smaller dimension in the Z direction can be detected as the remaining modeling material. Therefore, for example, by determining the positions of the light-emitting unit 610 and the light-receiving unit 620 so that the distance between the detection light DR and the stage 300 is smaller than the gap Gp, a modeling material that may come into contact with the discharge unit 200 when forming a three-dimensional object OB can be detected as the remaining modeling material. Also, similar to the case of determining the judgment period, the distance between the detection light DR and the stage 300 may be determined so that a modeling material that is small enough not to interfere with the operation of the discharge unit 200 and the like when forming a three-dimensional object OB can be ignored.

[0045] 10, when the remaining modeling material is detected, the control unit 500 notifies the user that the remaining modeling material has been detected by the notification unit 800 in step S126. Next, in step S127, the control unit 500 causes the three-dimensional modeling apparatus 100 to wait. For example, while the three-dimensional modeling apparatus 100 is waiting in step S127, the user can remove the remaining modeling material remaining on the modeling surface 311 from the modeling surface 311. In step S127, the control unit 500 may cause the three-dimensional modeling apparatus 100 to wait for a predetermined period of time, or may cause the three-dimensional modeling apparatus 100 to wait until a predetermined resume operation is input by the user. After step S127, the control unit 500 returns the process to step S121.

[0046] If no remaining modeling material is detected in step S125, the control unit 500 ends the remaining detection process. After that, in step S130 in Fig. 6, the control unit 500 controls the discharge unit 200 and the position change unit 400 to start stacking the modeling material on the modeling surface 311, thereby starting modeling of a three-dimensional object. That is, in this embodiment, the remaining detection process is executed prior to modeling of a three-dimensional object, and the processes from step S121 to S124 in the remaining modeling process in Fig. 10 are repeatedly executed until no remaining modeling material is detected in step S125. Therefore, modeling of a three-dimensional object is not started until no remaining modeling material is detected on the modeling surface 311.

[0047] According to the three-dimensional printing apparatus 100 of the present embodiment described above, the control unit 500 controls the sensor unit 600, which detects the printing material supported on the printing surface 311, to execute a remaining detection process of detecting the remaining printing material prior to printing of a three-dimensional object. In this way, when the control unit 500 detects the remaining printing material, the remaining printing material can be removed from the printing surface 311 before starting printing of a three-dimensional object. This makes it possible to prevent damage to the discharge unit 200 and the like of the three-dimensional printing apparatus 100 due to contact between the discharge unit 200 and the remaining printing material. In addition, it is possible to prevent damage to a three-dimensional object previously printed on the printing surface 311 due to contact between the discharge unit 200 and the like.

[0048] In the present embodiment, the sensor unit 600 includes a light-emitting unit 610 and a light-receiving unit 620 that faces the light-emitting unit 610 across the modeling surface 311 in the X direction. In the remaining detection process, the control unit 500 moves the sensor unit 600 relative to the stage 300 along the Y direction while emitting the detection light DR from the light-emitting unit 610 in the X direction. Therefore, the remaining modeling material can be detected more easily without contacting the sensor unit 600 with the remaining modeling material. In particular, in the present embodiment, the start position is a position where the detection light DR emitted from the light-emitting unit 610 located at the start position overlaps with one end Eg1 in the Y direction of the modeling surface 311 when viewed along the Z direction, and the end position is a position where the detection light DR emitted from the light-emitting unit 610 located at the end position overlaps with the other end Eg2 in the Y direction of the modeling surface 311 when viewed along the Z direction. Therefore, the remaining modeling material can be detected more efficiently, regardless of its position on the modeling surface 311 in the X and Y directions.

[0049] In the present embodiment, the control unit 500 determines that the remaining modeling material has been detected in the remaining detection process when the detection value of the detection light DR by the light receiving unit 620 is smaller than a reference value over a predetermined determination period. In this manner, by setting the determination period to a period during which modeling material that is small enough not to interfere with the operation of the discharging unit 200 and the like when forming a three-dimensional object is not detected, such small modeling material can be ignored without being detected in the remaining detection process. Therefore, a three-dimensional object can be more efficiently formed while suppressing damage to a previously formed three-dimensional object, the discharging unit 200, and the like.

[0050] In the present embodiment, the control unit 500 starts forming a three-dimensional object when no remaining modeling material is detected in the remaining detection process. This makes it possible to form a three-dimensional object while suppressing damage to a previously formed three-dimensional object, the discharging unit 200, etc.

[0051] In addition, in this embodiment, the three-dimensional printing apparatus 100 includes a heating unit 700 that moves according to the movement of the discharge unit 200, and the nozzle opening 62 is located between the heating unit 700 and the printing surface 311 in the Z direction. As a result, compared to a configuration in which the heating unit 700 is located between the nozzle opening 62 and the printing surface 311 in the Z direction, the possibility of the printing material layered on the printing surface 311 coming into contact with the heating unit 700 during printing of the three-dimensional object is low, and the possibility of printing the three-dimensional object with high accuracy is increased. In addition, since the control unit 500 executes the remaining detection process before printing of the three-dimensional object is started, damage to the heating unit 700 due to contact between the heating unit 700 and the printing material remaining on the printing surface 311 can be suppressed. In addition, damage to the previously printed three-dimensional object due to contact between the heating unit 700 and the three-dimensional object previously printed on the printing surface 311 can be suppressed.

[0052] In addition, in this embodiment, the sensor unit 600 is disposed at a position where it does not overlap with the heating unit 700 when viewed along the Z direction. Therefore, the influence of the heat of the heating unit 700 on the sensor unit 600 is suppressed. Note that, for example, even in a case where the positional relationship between the sensor unit 600 and the heating unit 700 can be changed in the X direction and the Y direction in another embodiment, the sensor unit 600 is disposed at a position where it does not overlap with the heating unit 700 when viewed along the Z direction, regardless of how the relative position of the sensor unit 600 with respect to the heating unit 700 is changed by the position change unit 400, so that the influence of the heat of the heating unit 700 on the sensor unit 600 can be suppressed.

[0053] In addition, in this embodiment, the position changer 400 moves the discharger 200 along the Z direction relative to the stage 300, and moves the stage 300 in the X and Y directions relative to the discharger 200. This allows the relative position between the discharger 200 and the stage 300 to be changed without moving the heating unit 700, which moves according to the discharger 200, in the X and Y directions relative to the stage 300. Therefore, compared to the case where the discharger 200 is moved in the X and Y directions relative to the stage 300, the position changer 400 can change the relative position between the discharger 200 and the stage 300 more stably. In particular, for example, even if the heating unit 700 is enlarged in the X and Y directions to cover the modeling surface 311 and the weight of the heating unit 700 increases, the relative position between the discharger 200 and the stage 300 can be changed more stably. Furthermore, in the case where the position changing unit 400 functions as the first moving unit as in this embodiment, the position changing unit 400 moves the discharge unit 200 along the Z direction relative to the stage 300, and moves the stage 300 in the Y direction relative to the discharge unit 200, thereby making it possible to move the sensor unit 600 relatively along the Y direction relative to the stage 300 while keeping the position of the sensor unit 600 fixed. Therefore, deviations in the position and angle of the sensor unit 600 are suppressed, and the detection accuracy of the remaining modeling material in the remaining detection step is improved.

[0054] B. Second embodiment: FIG. 11 is a diagram showing a schematic configuration of a three-dimensional modeling apparatus 100b in the second embodiment. In this embodiment, unlike the first embodiment, the position changer 400b moves the stage 300 in the X-direction, Y-direction, and Z-direction with respect to the discharger 200, thereby moving the discharger 200 relative to the stage 300. In addition to functioning as a first moving unit, the position changer 400b also functions as a second moving unit that moves the sensor unit 600 along the stacking direction, i.e., along the Z-direction, relative to the stage 300. In this embodiment, the control unit 500 measures the dimensions of a three-dimensional modeled object. Parts of the configuration of the three-dimensional modeling apparatus 100b that are not particularly described are similar to those of the first embodiment.

[0055] In this embodiment, the control unit 500 measures the dimensions in the Y direction and the Z direction of the three-dimensional object after it has been formed in the forming process shown in Fig. 6, that is, the completed three-dimensional object. More specifically, in this embodiment, the control unit 500 forms a three-dimensional object corresponding to the linear portion LP described in Fig. 5 in the forming process. Then, after the forming process is completed, the control unit 500 measures the dimensions of the three-dimensional object.

[0056] The control unit 500 measures the dimension in the Y direction of the three-dimensional object after modeling by controlling the sensor unit 600 and the position change unit 400b functioning as a first moving unit. More specifically, the control unit 500 measures the dimension in the Y direction of the three-dimensional object after modeling by moving the sensor unit 600 relatively to the stage 300 along the Y direction while emitting the detection light DR from the light-emitting unit 610. The control unit 500 also measures the dimension in the Z direction of the three-dimensional object after modeling by controlling the sensor unit 600 and the position change unit 400b functioning as a second moving unit. More specifically, the control unit 500 measures the dimension in the Z direction of the three-dimensional object after modeling by moving the sensor unit 600 relatively to the stage 300 along the Z direction while emitting the detection light DR from the light-emitting unit 610.

[0057] FIG. 12 is a diagram showing an example of how the dimension W2 of the three-dimensional object OB2 in the Y direction is measured by the dimension measurement. FIG. 12 shows a trajectory Lc2 of the detection light DR in the Y direction. The trajectory Lc2 is drawn by moving the light-emitting unit 610, which emits the detection light DR proceeding in the -X direction, in the +Y direction by the position change unit 400, similar to the trajectory Lc described in FIG. 9. The dimension W2 shown in FIG. 12 corresponds to the line width of the modeling material in the three-dimensional object OB2. In the example of FIG. 12, the intensity of the detection light DR received by the light-receiving unit 620 decreases during the period during which the detection light DR is irradiated to the three-dimensional object OB2 during the period during which the sensor unit 600 moves in the +Y direction, similar to the case in which the detection light DR is irradiated to the remaining modeling material. Therefore, the control unit 500 can measure the dimension of the three-dimensional object OB2 in the Y direction by calculating the difference between the coordinate where the intensity of the detection light DR received by the light-receiving unit 620 decreases and the coordinate where the intensity increases again. In addition, in other embodiments, the control unit 500 may measure the dimension W2 based on, for example, the period during which the intensity of the detection light DR received by the light receiving unit 620 is small and the moving speed of the sensor unit 600 along the Y direction during that period.

[0058] FIG. 13 is a diagram showing an example of how the dimension H of the three-dimensional object OB2 in the Z direction is measured by the dimension measurement. FIG. 13 shows a trajectory Lc3 of the detection light DR in the Z direction in the dimension measurement. The trajectory Lc3 is drawn by moving the light emitting unit 610, which emits the detection light DR proceeding in the -X direction, in the +Z direction by the position changing unit 400. The dimension H shown in FIG. 13 corresponds to the layer pitch of the modeling material in the three-dimensional object OB2. As shown in FIG. 13, in this embodiment, when the measurement of the dimension H of the three-dimensional object OB2 in the Z direction is started, the detection light DR advances in the +Y direction from the modeling surface 311 by a distance D. Therefore, when measuring the dimension H, the control unit 500 measures the dimension H by adding the distance D to the difference between the coordinate where the intensity of the received detection light DR decreases and the coordinate where the intensity increases again. The distance D is measured in advance using, for example, a feeler gauge or the like. In another embodiment, for example, the three-dimensional object OB2 may be shaped so as to bridge two bases having approximately the same height and spaced apart in the X direction or Y direction. In this case, since a space is formed between the three-dimensional object OB2 and the printing surface 311, the dimension H can be measured simply based on the difference between the coordinate where the intensity of the received detection light DR decreases and the coordinate where the intensity increases again. Note that in another embodiment, the control unit 500 may measure the dimension H based on, for example, the period during which the intensity of the detection light DR received by the light receiving unit 620 decreases and the moving speed of the sensor unit 600 along the Z direction during that period.

[0059] The control unit 500 may, for example, control the notification unit 800 to notify the user of each measured dimension. This allows the user to grasp, for example, the difference between the predicted value and the measured value of the dimension of the three-dimensional object OB2. The control unit 500 may also compare the measured value of each dimension of the three-dimensional object OB2 with the predicted value of the dimension of the three-dimensional object OB2 predicted from the control values ​​of the plasticizing unit 30 and the position changing unit 400, and change the control values ​​of the plasticizing unit 30 and the position changing unit 400 in the modeling process to be executed next based on the comparison result. For example, when the measured dimension H is smaller than the predicted value of the dimension in the Z direction of the three-dimensional object OB2, the control unit 500 may change the control value of the position changing unit 400b so as to increase the gap Gp described in FIG. 5. Furthermore, when the measured dimension W2 is larger than a predicted value of the dimension of the three-dimensional object OB2 in the Y direction, the control unit 500 may reduce the amount of the modeling material discharged from the nozzle opening 62 by lowering the rotation speed of the drive motor 32. This increases the possibility of forming a three-dimensional object having the desired dimensions. Note that in another embodiment, for example, when a valve, plunger, or the like that adjusts the amount of modeling material discharged from the nozzle opening 62 is provided in the nozzle flow path 65 of the discharge unit 200, the control unit 500 may change the control value of the valve, plunger, or the like based on the result of the comparison of the dimensions.

[0060] In another embodiment, the control unit 500 may measure the dimensions of the three-dimensional object being modeled during the modeling process. For example, after one linear portion constituting the three-dimensional object is modeled, the control values ​​of the plasticizing unit 30 and the position changing unit 400 can be changed when modeling a portion to be modeled after the linear portion based on a comparison result between the predicted value and the measured value of the dimension of the linear portion, as described in FIG. 12 and FIG. 13. This increases the possibility of modeling a three-dimensional object having the desired dimensions, as in the present embodiment. In addition, the control unit 500 may measure the dimensions of the entire three-dimensional object after modeling, for example. In this case, the difference between the predicted value and the measured value of the dimension of the entire three-dimensional object can be grasped.

[0061] The 3D printing apparatus 100b of this embodiment described above can also suppress damage to a previously printed three-dimensional object, the discharging unit 200, etc. In particular, in this embodiment, the sensor unit 600 and the position change unit 400b functioning as the first moving unit are controlled to measure the dimension in the Y direction of the three-dimensional object being printed or after printing. Therefore, the dimension in the Y direction of the three-dimensional object being printed or after printing can be easily measured.

[0062] In this embodiment, the control unit 500 measures the dimension in the Z direction of the three-dimensional object after modeling by controlling the sensor unit 600 and the position change unit 400b functioning as the second moving unit. Therefore, it is possible to easily measure the dimension in the Z direction of the three-dimensional object during or after modeling.

[0063] In other embodiments, the control unit 500 may, for example, measure only the dimension of the three-dimensional object in the Z direction during or after formation, and not measure the dimension in the Y direction, or similarly, may measure only the dimension of the three-dimensional object in the Y direction, and not measure the dimension in the Z direction.

[0064] C. Third embodiment: 14 is a diagram showing a schematic configuration of a three-dimensional printing apparatus 100c according to the third embodiment. In this embodiment, the control unit 500 executes an inspection process, which will be described later, prior to executing a remaining detection process. Parts of the configuration of the three-dimensional printing apparatus 100c that are not particularly described are similar to those of the first embodiment.

[0065] As shown in Fig. 14, a reference object 320 having a predetermined height Hs is placed on the stage 300 of this embodiment. More specifically, in this embodiment, a first reference object 321 and a second reference object 322 are placed and fixed on the upper surface of the stage 300 as the reference object 320. The first reference object 321 is placed on the upper surface of the stage 300 at a position in the -Y direction from the printing surface 311. The second reference object 322 is placed on the upper surface of the stage 300 at a position on the opposite side of the first reference object 321 in the Y direction across the printing surface 311. In other words, the printing surface 311 is located between the first reference object 321 and the second reference object 322 in the Y direction.

[0066] The inspection step described above refers to a step in which the control unit 500 detects the levelness of the stage 300 by emitting the detection light DR from the light emitting unit 610 and detecting the reference object 320 placed on the stage 300. In this embodiment, the control unit 500 detects the reference object 320 placed on the stage 300 by moving the sensor unit 600 relative to the stage 300 along the Y direction while emitting the detection light DR from the light emitting unit 610 in the inspection step. More specifically, in the inspection step, the control unit 500 moves the sensor unit 600 relative to the stage 300 from a position where the detection light DR overlaps with an end Eg3 in the -Y direction of the stage 300 to a position where the detection light DR overlaps with an end Eg4 in the +Y direction of the stage 300 when viewed along the Z direction.

[0067] As described above, the control unit 500 detects the horizontality of the stage 300 in the inspection process. For example, if only one of the reference objects 320 is detected and the other reference object 320 is not detected in the inspection process, the control unit 500 detects that the stage 300 is tilted with respect to the Y axis. Note that, if both of the reference objects 320 are not detected in the inspection process, the control unit 500 can also detect that the distance between the detection light DR and the upper surface of the stage 300 is greater than the height Hs.

[0068] The control unit 500 may, for example, control the notification unit 800 to notify the user of the detection result of the horizontality of the stage 300. Furthermore, the inspection process may be repeatedly executed until it is determined that the stage 300 is not tilted with respect to the Y-axis.

[0069] The three-dimensional modeling apparatus 100c of the present embodiment described above can also suppress damage to a previously modeled three-dimensional object, the discharge unit 200, and the like. In particular, in the present embodiment, the control unit 500 executes an inspection step of detecting the levelness of the stage 300 by emitting the detection light DR from the light-emitting unit 610 and detecting the reference object 320 placed on the stage 300 prior to executing the remaining detection step. This allows the sensor unit 600 to detect the levelness of the stage 300 prior to the start of the remaining detection step or the start of modeling of a three-dimensional object. In particular, in the present embodiment, the possibility of executing the remaining detection step in a state where the inclination of the stage 300 with respect to the Y direction is smaller is increased, and therefore the possibility of improving the detection accuracy of the remaining modeling material in the remaining detection step is increased.

[0070] In other embodiments, the reference object 320 does not need to be fixed to the stage 300, and may be placed on the stage 300 by a robot operating under the control of the control unit 500 or manually, for example, immediately before the inspection process is performed. In this case, for example, the inspection process may be performed multiple times, and the position in the X direction of the stage 300 on which the reference object 320 is placed may be changed each time the inspection process is performed, thereby detecting the tilt of the stage 300 in the X direction. More specifically, for example, the inspection process may be performed by the control unit 500 with the reference object 320 placed on the upper surface of the stage 300 at a position in the -X direction from the modeling surface 311, and then the inspection process may be performed by the control unit 500 with the reference object 320 placed on the upper surface of the stage 300 at a position on the opposite side of the modeling surface 311 in the X direction. At this time, if the reference object 320 is detected in one inspection process and the reference object 320 is not detected in the other inspection process, the stage 300 is inclined with respect to the X direction, which is the traveling direction of the detection light DR. In this way, the control unit 500 can detect the inclination of the stage 300 with respect to the X direction. In addition, for example, it is also possible to estimate the distance between the detection light DR and the upper surface of the stage 300 by performing the inspection process multiple times and placing a reference object 320 having a different height on the stage 300 each time the inspection process is performed. For example, if the reference object 320 having the height Hs1 is not detected in the first reference object detection, and the reference object 320 having the height Hs2 higher than the height Hs1 and placed at the same position as the first reference object detection is detected in the second reference object detection, the control unit 500 can estimate that the distance between the detection light DR and the upper surface of the stage 300 is greater than the height Hs1 and is equal to or less than the height Hs2.

[0071] D. Other embodiments: (D-1) In the above embodiment, the sensor unit 600 detects the modeling material supported on the modeling surface 311. In contrast, the sensor unit 600 may detect other residues supported on the modeling surface 311. For example, the sensor unit 600 may detect tools left behind on the modeling surface 311 by a user, or parts such as screws that have fallen from the discharge unit 200 onto the modeling surface 311, as the residues. The control unit 500 may control the sensor unit 600 to detect the residues remaining on the modeling surface 311 prior to the start of modeling of a three-dimensional object. In this way, when the residues are detected, the residues can be removed from the modeling surface 311 before the start of modeling of a three-dimensional object. This makes it possible to prevent damage to the residues or the discharge unit 200, etc., caused by contact between the residues and each part of the three-dimensional modeling device 100, such as the discharge unit 200.

[0072] (D-2) In the above embodiment, the sensor unit 600 is configured with an optical sensor. However, the sensor unit 600 may be another sensor. For example, the sensor unit 600 may be a temperature sensor that detects the temperature of the object supported on the printing surface 311, a non-contact type temperature sensor configured with an infrared radiation thermometer or a thermal camera, or a contact type temperature sensor that is provided on the printing surface 311 and detects the temperature of the object supported on the printing surface 311. In this case, the detection unit 510 may perform the remaining detection process before the printing of the object is started and while the remaining printing material has a temperature that can be detected by the temperature sensor. In addition, the sensor unit 600 may be configured with a weight sensor such as a load cell type or an electromagnetic force balance type that measures the weight of the object stacked on the stage 300.

[0073] (D-3) In the above embodiment, the light-emitting unit 610 and the light-receiving unit 620 are arranged to be oriented relative to each other in the X direction. In contrast, the light-emitting unit 610 and the light-receiving unit 620 do not have to be arranged opposite each other. For example, a reflector that reflects the detection light DR emitted from the light-emitting unit 610 may be arranged at a position opposite the light-emitting unit 610 across the modeling surface 311 in the X direction, and the light-receiving unit 620 may be arranged opposite the reflector.

[0074] (D-4) In the above embodiment, the start position is a position where the detection light DR emitted from the light-emitting unit 610 located at the start position overlaps with one end Eg1 in the Y direction of the printing surface 311 when viewed along the Z direction, and the end position is a position where the detection light DR emitted from the light-emitting unit 610 located at the end position overlaps with the other end Eg2 in the Y direction of the printing surface 311 when viewed along the Z direction. In contrast, the start position and the end position may be positions different from the above-mentioned positions. For example, the start position and the end position may be positions outside the printing surface 311 in the Y direction. Even in this case, the remaining printing material can be detected more efficiently regardless of the position in the X direction and the Y direction on the printing surface 311. In addition, the start position may be, for example, the center position in the Y direction of the printing surface 311. In this case, in the remaining detection process, the control unit 500 may, for example, move the sensor unit 600 in the -Y direction or +Y direction, and then move the sensor unit 600 in the opposite direction, and may then return the sensor unit 600 to the center position in the Y direction to end the movement of the sensor unit 600. In addition, in the remaining detection process, the control unit 500 may stop the movement of the sensor unit 600 at the time point when the control unit 500 detects remaining modeling material while moving the sensor unit 600 from the start position to the end position. In this case, the remaining modeling material can be detected more efficiently by setting the start position to a position where there is a higher possibility that the remaining modeling material remains, for example, the center position in the Y direction of the above-mentioned modeling surface 311.

[0075] (D-5) In the above embodiment, the position changer 400 functions as the first movement unit and the second movement unit. In contrast, the position changer 400 does not have to function as the first movement unit and the second movement unit. For example, a movement unit that simultaneously moves the light emitter 610 and the light receiver 620 in the X direction, Y direction, and Z direction relative to the stage 300 may be provided separately from the position changer 400.

[0076] (D-6) In the above embodiment, the detection unit 510 determines that the remaining modeling material has been detected when the detection value of the detection light DR by the light receiving unit 620 becomes smaller than a reference value over a predetermined determination period in the remaining detection process. In contrast, the determination period does not need to be determined, and for example, the control unit 500 may determine that the remaining modeling material has been detected when the intensity of the detection light DR received by the light receiving unit 620 becomes smaller than a reference value in the remaining detection process. In addition, the detection unit 510 may determine that the remaining modeling material has been detected when the detection value of the detection light DR by the light receiving unit 620 becomes 0, for example.

[0077] (D-7) In the above embodiment, there is provided a heating unit 700. However, the heating unit 700 does not necessarily have to be provided.

[0078] (D-8) In the above embodiment, the heating unit 700 and the sensor unit 600 are disposed in positions where they do not overlap each other when viewed along the Z direction. In contrast, the heating unit 700 and the sensor unit 600 may be disposed in positions where they overlap each other when viewed along the Z direction.

[0079] (D-9) In the above embodiment, the plasticizing unit 30 of the discharge unit 200 plasticizes the material by a flat screw to generate the modeling material. In contrast, the plasticizing unit 30 may generate the modeling material by, for example, rotating an in-line screw. In addition, the discharge unit 200 may be configured as a head that plasticizes and discharges a filament-shaped material.

[0080] (D-10) In the above embodiment, a pellet-shaped ABS resin material is used as the raw material supplied to the material supply unit 20. In contrast, the three-dimensional modeling device 100 can model a three-dimensional object using various materials, such as a thermoplastic material, a metal material, or a ceramic material, as the main material. Here, the "main material" refers to a material that is the core material forming the shape of the three-dimensional object, and a material that occupies 50% by weight or more in the three-dimensional object. The modeling materials mentioned above include those main materials that are melted alone, and those that are made into a paste by melting some components contained together with the main material.

[0081] When a material having thermoplastic properties is used as the main material, the modeling material is generated by plasticizing the material in the plasticizing unit 30. "Plasticizing" means that heat is applied to the material having thermoplastic properties to melt it.

[0082] As the material having thermoplasticity, for example, the following thermoplastic resin materials can be used. <Examples of thermoplastic resin materials> General-purpose engineering plastics such as polypropylene resin (PP), polyethylene resin (PE), polyacetal resin (POM), polyvinyl chloride resin (PVC), polyamide resin (PA), acrylonitrile butadiene styrene resin (ABS), polylactic acid resin (PLA), polyphenylene sulfide resin (PPS), polyether ether ketone (PEEK), polycarbonate (PC), modified polyphenylene ether, polybutylene terephthalate, and polyethylene terephthalate, as well as engineering plastics such as polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, polyimide, polyamideimide, polyetherimide, and polyether ether ketone.

[0083] The thermoplastic material may contain additives such as pigments, metals, ceramics, wax, flame retardants, antioxidants, and heat stabilizers. The thermoplastic material is plasticized in the plasticizing section 30 by the rotation of the screw 40 and the heat of the heater 58, and is converted into a molten state. The modeling material produced by melting the thermoplastic material is discharged from the nozzle 61, and then hardens as the temperature drops.

[0084] It is desirable that the thermoplastic material be heated to or above its glass transition point and in a completely molten state before being injected from the nozzle 61. For example, ABS resin has a glass transition point of about 120° C., and it is desirable that the temperature of ABS resin is about 200° C. when it is injected from the nozzle 61.

[0085] In the three-dimensional modeling apparatus 100, for example, the following metal materials may be used as the main materials instead of the above-mentioned thermoplastic materials. In this case, it is preferable that the powder material made by powdering the following metal materials is mixed with a component that melts when the modeling material is generated, and then the powder material is introduced into the plasticization unit 30 as a raw material. <Examples of metal materials> A single metal, or an alloy containing one or more of the following metals: magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr), aluminum (Al), titanium (Ti), copper (Cu), or nickel (Ni). <Examples of the alloy> Maraging steel, stainless steel, cobalt chrome molybdenum, titanium alloy, nickel alloy, aluminum alloy, cobalt alloy, cobalt chrome alloy.

[0086] In the three-dimensional modeling apparatus 100, a ceramic material can be used as the main material instead of the above-mentioned metal materials. As the ceramic material, for example, oxide ceramics such as silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, and non-oxide ceramics such as aluminum nitride can be used. When the above-mentioned metal materials or ceramic materials are used as the main material, the modeling material placed on the stage 300 may be hardened by sintering using laser irradiation, hot air, or the like.

[0087] The powder material of the metallic material or the ceramic material fed as a raw material to the material supply unit 20 may be a mixed material in which a single metal powder, an alloy powder, or a ceramic material powder is mixed with a plurality of types of powder. The powder material of the metallic material or the ceramic material may be coated with, for example, the thermoplastic resin exemplified above or a thermoplastic resin other than the above. In this case, the thermoplastic resin may be melted in the plasticizing unit 30 to exhibit fluidity.

[0088] For example, the following solvents can be added to the powdered metal or ceramic material fed as raw material to the material supply unit 20. The solvent can be one or a combination of two or more selected from the following: <Examples of solvents> water; (poly)alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; acetate esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, and iso-butyl acetate; aromatic hydrocarbons such as benzene, toluene, and xylene; ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, ethyl-n-butyl ketone, diisopropyl ketone, and acetylacetone; alcohols such as ethanol, propanol, and butanol; tetraalkylammonium acetates; sulfoxide-based solvents such as dimethyl sulfoxide and diethyl sulfoxide; pyridine-based solvents such as pyridine, γ-picoline, and 2,6-lutidine; tetraalkylammonium acetates (for example, tetrabutylammonium acetate, etc.); and ionic liquids such as butyl carbitol acetate.

[0089] In addition, the powdered metal or ceramic material fed to the material supply unit 20 as a raw material may also contain a binder, for example, as described below. <Example of binder> Acrylic resin, epoxy resin, silicone resin, cellulose resin or other synthetic resin, or PLA (polylactic acid), PA (polyamide), PPS (polyphenylene sulfide), PEEK (polyether ether ketone) or other thermoplastic resin.

[0090] E. Other forms: The present disclosure is not limited to the above-mentioned embodiment, and can be realized in various forms without departing from the spirit of the present disclosure. For example, the present disclosure can be realized in the following forms. The technical features in the above-mentioned embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined in order to solve some or all of the problems of the present disclosure, or to achieve some or all of the effects of the present disclosure. Furthermore, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0091] (1) According to one aspect of the present disclosure, there is provided a three-dimensional modeling apparatus. The three-dimensional modeling apparatus includes a discharge unit having a nozzle opening and discharging a modeling material from the nozzle opening, a stage having a modeling surface that supports the modeling material discharged from the discharge unit, a sensor unit that detects the modeling material supported on the modeling surface, and a control unit that controls the discharge unit to stack the modeling material on the modeling surface to form a three-dimensional object. Prior to starting modeling of the three-dimensional object, the control unit controls the sensor unit to execute a remaining detection step of detecting the modeling material remaining on the modeling surface. According to this embodiment, when the remaining modeling material on the modeling surface is detected, the modeling material can be removed from the modeling surface before starting modeling of a three-dimensional object. This makes it possible to prevent damage to the discharge unit, etc., of the three-dimensional modeling device due to contact between the remaining modeling material on the modeling surface and each part of the three-dimensional modeling device, such as the discharge unit. It is also possible to prevent damage to a previously modeled three-dimensional object due to contact between the previously modeled three-dimensional object on the modeling surface and the discharge unit, etc.

[0092] (2) In the above embodiment, the sensor unit includes a light-emitting unit that emits detection light in a first direction along the modeling surface, and a light-receiving unit that faces the light-emitting unit across the modeling surface in the first direction and receives the detection light, and further includes a first moving unit that moves the sensor unit relative to the stage along a second direction that is along the modeling surface and intersects with the first direction, and the control unit may move the sensor unit relative to the stage along the second direction while emitting the detection light from the light-emitting unit in the remaining detection step. According to this embodiment, the remaining modeling material on the modeling surface can be detected more easily without contact between the sensor unit and the modeling material remaining on the modeling surface.

[0093] (3) In the above embodiment, the detection unit may determine that the remaining modeling material on the modeling surface has been detected when the detection value of the detection light by the light receiving unit becomes smaller than a predetermined value over a predetermined period in the remaining detection process. According to this embodiment, the determination period may be set to a period in which modeling material that is small enough not to interfere with the operation of a discharge unit or the like when forming a three-dimensional object is not detected, so that such small modeling material can be ignored without being detected in the remaining detection process. Therefore, a three-dimensional object can be more efficiently formed while suppressing damage to a previously formed three-dimensional object, the discharge unit, etc.

[0094] (4) In the above embodiment, the control unit may execute an inspection step of detecting a levelness of the stage by emitting the detection light from the light-emitting unit and detecting a reference object placed on the stage prior to executing the remaining detection step. According to this embodiment, the levelness of the stage can be detected by the sensor unit prior to the start of the remaining detection step or the start of modeling of a three-dimensional object.

[0095] (5) In the above embodiment, the control unit may measure a dimension of the three-dimensional object in the second direction during or after modeling by controlling the sensor unit and the first movement unit. According to this embodiment, it is possible to easily measure the dimension of the three-dimensional object in the second direction during or after modeling.

[0096] (6) In the above embodiment, the sensor unit may further include a second moving unit that moves the sensor unit relative to the stage along a stacking direction of the modeling material, and the detection unit may measure a dimension of the three-dimensional object in the stacking direction during or after modeling by controlling the sensor unit and the second moving unit. According to this embodiment, it is possible to easily measure the dimension of the three-dimensional object in the stacking direction during or after modeling.

[0097] (7) In the above aspect, the control unit may start modeling of the three-dimensional object when no remaining modeling material is detected on the modeling surface in the remaining detection step. According to this aspect, it is possible to model a three-dimensional object while suppressing damage to a previously modeled three-dimensional object, a discharge unit, etc.

[0098] (8) In the above embodiment, the position changer may move the discharger relative to the stage, and the heater may move according to the movement of the discharger to heat the modeling material layered on the modeling surface, and the nozzle opening may be located between the heater and the modeling surface in a third direction perpendicular to the modeling surface. According to this embodiment, the possibility of the modeling material layered on the modeling surface coming into contact with the heater during modeling of the three-dimensional object is low compared to the embodiment in which the heater is located between the nozzle opening and the modeling surface in the third direction, so that the possibility of the three-dimensional object being modeled with high accuracy is increased. In addition, the remaining detection step is performed before modeling of the three-dimensional object is started, so that damage to the heater due to contact between the heater and the modeling material remaining on the modeling surface can be suppressed. In addition, damage to the previously modeled three-dimensional object due to contact between the heater and the three-dimensional object previously modeled on the modeling surface can be suppressed.

[0099] (9) In the above embodiment, the sensor unit may be disposed at a position not overlapping with the heating unit when viewed in the third direction. According to this embodiment, the sensor unit is prevented from being affected by heat from the heating unit.

[0100] (10) In the above embodiment, the position changer may move the discharger relative to the stage along the third direction, and move the stage relative to the discharger along a direction perpendicular to the third direction. According to this embodiment, the relative position between the discharger and the stage can be changed without moving the heating unit, which moves following the discharger, along a direction perpendicular to the third direction relative to the stage. Therefore, the relative position between the discharger and the stage can be changed more stably by the position changer, compared to the case where the discharger is moved along a direction perpendicular to the third direction relative to the stage. [Explanation of symbols]

[0101] 20...material supply section, 22...supply path, 30...plasticization section, 31...screw case, 32...driving motor, 40...screw, 41...upper surface, 42...groove forming surface, 43...side surface, 44...material inlet, 45...groove, 46...ridge portion, 47...center portion, 50...barrel, 52...screw facing surface, 54...guide groove, 56...communicating hole, 58...heater, 61...nozzle, 62...nozzle opening, 63...tip surface, 65...nozzle flow path, 100, 100b, 100c...three-dimensional modeling device, 200...discharge section, 205...support section, 300...stay 311...printing surface, 320...reference object, 321...first reference object, 322...second reference object, 400, 400b...position changing unit, 410...first electric actuator, 420...second electric actuator, 430...third electric actuator, 500...control unit, 510...detection unit, 600...sensor unit, 601...first support unit, 602...first holder, 603...first support column, 604...second support unit, 605...second holder, 606...second support column, 610...light emitting unit, 620...light receiving unit, 700...heating unit, 800...notification unit

Claims

1. A discharge unit having a nozzle opening and discharging a modeling material from the nozzle opening; a stage having a modeling surface for supporting the modeling material discharged from the discharge portion; a sensor unit that detects the modeling material supported on the modeling surface, the sensor unit having a light-emitting unit that emits detection light in a first direction along the modeling surface, and a light-receiving unit that faces the light-emitting unit across the modeling surface in the first direction and receives the detection light; a first moving unit that moves the sensor unit relatively to the stage along a second direction that is a direction along the modeling surface and intersects with the first direction; a control unit that controls the discharge unit to deposit the modeling material on the modeling surface to model a three-dimensional object, the control unit controls the sensor unit to execute a remaining detection step of detecting the modeling material remaining on the modeling surface prior to starting modeling of the three-dimensional object; In the remaining detection process, the sensor unit is moved relative to the stage along the second direction while emitting the detection light from the light-emitting unit, and when the detection value of the detection light by the light-receiving unit becomes smaller than a predetermined value over a predetermined period of time, it is determined that the modeling material remaining on the modeling surface has been detected.

2. The three-dimensional printing apparatus according to claim 1, The control unit controls the light emitting unit to emit the detection light prior to the remaining detection step. and detecting a reference object placed on the stage, A three-dimensional printing device that performs an inspection process to detect the levelness of the part.

3. A three-dimensional printing apparatus according to claim 1 or 2, The control unit controls the sensor unit and the first moving unit to measure a dimension of the three-dimensional object in the second direction during or after printing.

4. A three-dimensional printing apparatus according to any one of claims 1 to 3, a second moving unit that moves the sensor unit relative to the stage along a stacking direction of the modeling material, The control unit controls the sensor unit and the second moving unit to measure a dimension of the three-dimensional object in the stacking direction during or after modeling.

5. The three-dimensional modeling apparatus according to claim 1 , The control unit starts printing of the three-dimensional object when the remaining printing material on the printing surface is not detected in the remaining detection step.

6. The three-dimensional modeling apparatus according to claim 1 , a position changing unit that moves the discharge unit relatively to the stage; a heating unit that moves in accordance with the movement of the discharge unit and heats the modeling material that is layered on the modeling surface, A three-dimensional printing device, wherein the nozzle opening is located between the heating unit and the printing surface in a third direction perpendicular to the printing surface.

7. The three-dimensional modeling apparatus according to claim 6, A three-dimensional printing apparatus, wherein the sensor unit is disposed at a position not overlapping with the heating unit when viewed along the third direction.

8. A three-dimensional printing apparatus according to claim 6 or 7, the position change unit moves the discharge unit relative to the stage along the third direction, and moves the stage relative to the discharge unit along a direction perpendicular to the third direction; Three-dimensional printing equipment.

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