Patent Publication Number: US-2022234294-A1

Title: Three-Dimensional Shaping Device And Method For Manufacturing Three-Dimensional Shaped Object

Description:
The present application is based on, and claims priority from JP Application Serial Number 2021-009951, filed Jan. 26, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a three-dimensional shaping device and a method for manufacturing a three-dimensional shaped object. 
     2. Related Art 
     JP-T-2010-530326 discloses a three-dimensional shaping device including an end cleaning assembly which includes a flicker plate and a brush. In the three-dimensional shaping device, cleaning of an extrusion head is performed by bringing the extrusion head into contact with the flicker plate and the brush. 
     When the cleaning of the extrusion head is performed, the flicker plate and the brush are worn, so that the flicker plate and the brush may need to be replaced. Therefore, in the three-dimensional shaping device, there is a demand for a technique capable of preventing wear of a cleaning mechanism such as a flicker plate or a brush and reducing a frequency of replacement. 
     SUMMARY 
     According to a first aspect of the present disclosure, a three-dimensional shaping device is provided. The three-dimensional shaping device includes: an injection unit including a plasticizing mechanism configured to plasticize a plasticizing material to generate a shaping material and a nozzle, and configured to inject the shaping material from the nozzle; a stage on which the shaping material is to be stacked; a drive unit configured to change a relative position between the injection unit and the stage; a cleaning mechanism including a brush and a blade; and a control unit configured to execute a cleaning processing for cleaning the nozzle, in which the brush and the blade are disposed at a height at which the brush and the blade are able to come into contact with the nozzle, the brush and the blade have a melting point higher than a plasticizing temperature of the plasticizing material, and have hardness lower than hardness of the nozzle, in the cleaning processing, the control unit is configured to execute a cleaning operation of bringing at least one of the brush and the blade into contact with the nozzle by reciprocally moving the nozzle such that the nozzle cuts across the cleaning mechanism a plurality of times, and the control unit is configured to reciprocally move the nozzle such that the nozzle comes into contact with the brush or the blade at different positions in the cleaning operation. 
     According to a second aspect of the present disclosure, there is provided a method for manufacturing a three-dimensional shaped object in a three-dimensional shaping device, the three-dimensional shaping device including: an injection unit including a plasticizing mechanism configured to plasticize a plasticizing material to generate a shaping material and a nozzle, and configured to inject the shaping material from the nozzle; a stage on which the shaping material is to be stacked; a drive unit configured to change a relative position between the injection unit and the stage; and a cleaning mechanism including a brush and a blade, in which the brush and the blade are disposed at a height at which the brush and the blade are able to come into contact with the nozzle, and the brush and the blade have a melting point higher than a plasticizing temperature of the plasticizing material, and have hardness lower than hardness of the nozzle. This manufacturing method includes a shaping step of shaping a three-dimensional shaped object by injecting a shaping material from the injection unit to the stage; and a cleaning step of executing a cleaning operation of bringing at least one of the brush and the blade into contact with the nozzle by reciprocally moving the nozzle such that the nozzle cuts across the cleaning mechanism a plurality of times at any one timing of before the shaping step, during the shaping step and after the shaping step, in which in the cleaning step, the nozzle is reciprocally moved such that the nozzle comes into contact with the brush or the blade at different positions in the cleaning operation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a schematic configuration of a three-dimensional shaping device according to a first embodiment. 
         FIG. 2  is a diagram illustrating a schematic configuration of an injection unit. 
         FIG. 3  is a schematic perspective view illustrating a configuration of a screw. 
         FIG. 4  is a top view illustrating a configuration of a barrel. 
         FIG. 5  is a view illustrating a schematic configuration of a cleaning mechanism. 
         FIG. 6  is a flowchart of a three-dimensional shaping processing. 
         FIG. 7  is a flowchart of a cleaning processing. 
         FIG. 8  is a diagram illustrating a cleaning operation. 
         FIG. 9  is a diagram illustrating another example of the cleaning operation. 
         FIG. 10  is a diagram illustrating another example of the cleaning operation. 
         FIG. 11  is a diagram illustrating another example of the cleaning operation. 
         FIG. 12  is a diagram illustrating another example of the cleaning operation. 
         FIG. 13  is a diagram illustrating a schematic configuration of a three-dimensional shaping device according to a second embodiment. 
         FIG. 14  is a diagram illustrating a schematic configuration of a three-dimensional shaping device according to a third embodiment. 
         FIG. 15  is a diagram illustrating a schematic configuration of an injection unit according to the third embodiment. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     A. First Embodiment 
       FIG. 1  is a diagram illustrating a schematic configuration of a three-dimensional shaping device  10  according to a first embodiment. In  FIG. 1 , arrows along X, Y and Z directions orthogonal to one another are shown. The X, Y, and Z directions are directions along three spatial axes that are orthogonal to one another, that is, an X axis, a Y axis, and a Z axis, and include both one-side direction along the X axis, the Y axis, and the Z axis and an opposite direction. The X axis and the Y axis are axes along a horizontal plane, and the Z axis is an axis along a vertical line. A −Z direction is a vertical direction, and a +Z direction is a direction opposite to the vertical direction. The −Z direction is also referred to as “lower” side, and the +Z direction is also referred to as “upper” side. The X, Y and Z directions in  FIG. 1  and the X, Y and Z directions in other figures indicate the same directions. 
     The three-dimensional shaping device  10  of the present embodiment includes an injection unit  100 , a material accommodation unit  20 , a housing  110 , a drive unit  210 , a stage  220 , a cleaning mechanism  250 , a control unit  300 , and a display device  400  as a notification unit. 
     The injection unit  100  includes a plasticizing mechanism  30  that plasticizes at least a part of a plasticizing material supplied from the material accommodation unit  20  to generate a shaping material, and a nozzle  60 . The injection unit  100  emits the shaping material plasticized by the plasticizing mechanism  30  from the nozzle  60  toward the stage  220 . The injection unit  100  is also called an injection head, a discharge unit, a discharge head, an extrusion unit, an extrusion head, or simply a head. In the present specification, “injection” includes a meaning of “discharge” or “extrusion”. 
     The housing  110  has a shaping space  111  inside. The stage  220  on which the shaping material is stacked is disposed in the shaping space  111 . The housing  110  may be provided with, for example, an opening portion that allows communication between the shaping space  111  and the outside, a door that opens and closes the opening portion, and the like. By opening the door to make the opening portion at an opening state, a user can take out a shaped object shaped on the stage  220  from the opening portion. 
     The drive unit  210  changes a relative position between the injection unit  100  and the stage  220 . In the present embodiment, the drive unit  210  includes a first drive unit  211  that moves the stage  220  along the Z direction, and a second drive unit  212  that moves the injection unit  100  along the X direction and the Y direction. The first drive unit  211  is configured as an elevating device, and includes a motor for moving the stage  220  in the Z direction. The second drive unit  212  is configured as a horizontal conveyance device, and includes a motor for sliding the injection unit  100  along the X direction and a motor for sliding the injection unit  100  along the Y direction. Each motor is driven under control of the control unit  300 . In another embodiment, the drive unit  210  may be configured to move the stage  220  or the injection unit  100  in three directions of X, Y, and Z, or may be configured to move the stage  220  along the X direction and the Y direction to move the injection unit  100  in the Z direction. 
     The cleaning mechanism  250  includes a brush  251  and a blade  252  for cleaning the nozzle  60 . The cleaning mechanism  250  is disposed in a region different from the stage  220  in a horizontal direction. The cleaning mechanism  250  is disposed at a height at which the brush  251  and the blade  252  can come into contact with the nozzle  60  in the vertical direction. In the present embodiment, the cleaning mechanism  250  is coupled to a height adjustment device  280  provided in the housing  110 . The height adjustment device  280  includes a motor for moving the cleaning mechanism  250  along the Z direction under the control of the control unit  300 . Below the cleaning mechanism  250 , a purge waste material container  260  is provided. A resin dust removed by the cleaning mechanism  250  falls and is collected in the purge waste material container  260 . The blade  252  is also called a flicker plate. The cleaning mechanism  250  is also referred to as a tip wipe assembly. The height adjustment device  280  may be coupled to each of the brush  251  and the blade  252  of the cleaning mechanism  250 , and may be configured to individually adjust a height of each of the brush  251  and the blade  252 . 
     The control unit  300  is configured with a computer including one or more processors, a memory, and an input and output interface through which signals are input from or output to the outside. In the present embodiment, the control unit  300  controls the injection unit  100  and the drive unit  210  based on shaping data for shaping a three-dimensional shaped object by the processor executing a program or instruction read into the memory to execute a three-dimensional shaping processing and a cleaning processing for cleaning the nozzle to be described later. The control unit  300  may not be configured with the computer but with a combination of a plurality of circuits. 
     The display device  400  is coupled to the control unit  300 . The display device  400  is configured with, for example, a liquid crystal display or an organic EL display. In the present embodiment, the display device  400  is provided in the housing  110 , but the display device  400  may be disposed separately from the housing  110 . 
       FIG. 2  is a diagram illustrating a schematic configuration of the injection unit  100  according to the present embodiment. The injection unit  100  includes the plasticizing mechanism  30  and the nozzle  60 . The plasticizing mechanism  30  includes a material transport mechanism  40  and a heating block  90 . A material accommodated in the material accommodation unit  20  is supplied to the injection unit  100 . Under the control of the control unit  300 , the injection unit  100  plasticizes at least a part of the material supplied from the material accommodation unit  20  by the plasticizing mechanism  30  to generate the shaping material, and injects and stacks the generated shaping material from the nozzle  60  onto the stage  220 . The material stacked on the stage  220  may also be referred to as a stacked material. In a three-dimensional shaping method in which the material is injected from the nozzle and the injected material is stacked to shape a three-dimensional shaped object may be referred to as a material extrusion (ME) method. 
     In the present embodiment, a term “plasticization” means that heat is applied to a material having thermoplasticity to melt the material. A term “melt” means not only that a material having thermoplasticity is heated to a temperature equal to or higher than a melting point to become a liquid, but also that a material having thermoplasticity is heated to a temperature equal to or higher than a glass transition point to be softened, thereby exhibiting fluidity. 
     A material in a state of pellets, powder, or the like is accommodated in the material accommodation unit  20  of the present embodiment. In the present embodiment, the material accommodated in the material accommodation unit  20  is a pellet-shaped resin. The material accommodation unit  20  of the present embodiment is configured by a hopper. The material accommodated in the material accommodation unit  20  is supplied to the material transport mechanism  40  of the plasticizing mechanism  30  via a supply path  22  provided below the material accommodation unit  20  so as to couple the material accommodation unit  20  and the injection unit  100 . 
     The heating block  90  includes a heater  58 . The heater  58  is controlled by the control unit  300 , and is heated to a plasticizing temperature for plasticizing the material. The plasticizing temperature varies depending on a type of the material to be used, and is, for example, a glass transition point or a melting point of a material. When the material is an ABS resin, the plasticizing temperature is set to, for example, about 110° C., which is a glass transition point of the ABS resin. The heating block  90  is provided with a through hole  80 . The through hole  80  is configured to allow the nozzle  60  to be attached and detached. The material transport mechanism  40  transports the shaping material toward a nozzle flow path  61  of the nozzle  60  attached to the through hole  80  of the heating block  90 . The plasticizing mechanism  30  transports the material supplied from the material accommodation unit  20  to the material transport mechanism  40  toward the nozzle flow path  61  of the nozzle  60  by the material transport mechanism  40 , and heats and plasticizes the material by the heat of the heating block  90 . 
     The material transport mechanism  40  of the present embodiment includes a screw case  31 , a screw  41  accommodated in the screw case  31 , and a drive motor  32  for driving the screw  41 . The heating block  90  of the present embodiment includes a case  91  having an opening portion  94 , and a barrel  50  disposed in the case  91 . The barrel  50  is provided with a communication hole  56 . The through hole  80  of the present embodiment is formed by communication between the opening portion  94  and the communication hole  56 . The heater  58  is incorporated in the barrel  50 . The screw  41  of the present embodiment is a so-called flat screw and may be referred to as “scroll”. 
     The screw  41  has a substantially cylindrical shape in which a height in a direction along a central axis RX is smaller than a diameter. The screw  41  has a groove forming surface  42 , in which screw grooves  45  are formed, in a surface facing the barrel  50 . The groove forming surface  42  faces a screw facing surface  52  of the barrel  50 , which will be described later. The central axis RX of the present embodiment coincides with a rotation axis of the screw  41 . Details of a configuration of the screw  41  on a groove forming surface  42  side will be described later. 
     The drive motor  32  is coupled to an opposite-side surface of the screw  41  from the groove forming surface  42 . The drive motor  32  is driven under the control of the control unit  300 . The screw  41  rotates about the central axis RX by a torque generated by the rotation of the drive motor  32 . The drive motor  32  may not be directly coupled to the screw  41 , and may be coupled to the screw  41  via, for example, a speed reducer. 
     The barrel  50  has the screw facing surface  52  facing the groove forming surface  42  of the screw  41 . The case  91  is disposed so as to cover an opposite-side surface of the barrel  50  from the screw facing surface  52 , that is, a lower surface of the barrel  50 . The communication hole  56  and the opening portion  94  described above are provided at positions overlapping the central axis RX of the screw  41 . That is, the through hole  80  is located at a position overlapping the central axis RX. 
     As described above, the nozzle  60  is detachably attached to the through hole  80  of the heating block  90 . The nozzle  60  is also called a nozzle tip. The nozzle  60  is provided with the above nozzle flow path  61 . The nozzle flow path  61  has a nozzle opening  63  at a tip end of the nozzle  60 , and has an inflow port  65  at a rear end of the nozzle  60 . The nozzle opening  63  is located at a position in the −Z direction of the inflow port  65 . The material which flows into the nozzle flow path  61  through the through hole  80  and the inflow port  65  are discharged via the nozzle  60  of the present embodiment from the nozzle opening  63  toward the stage  220 . The nozzle  60  includes a shield  68  above the tip end of the nozzle  60 . More specifically, the shield  68  is disposed between the nozzle opening  63  and the heating block  90  on an outer periphery of the nozzle  60 . The shield  68  has a disc shape along the horizontal direction. The shield  68  prevents the heat of the heating block  90  from being transferred to the stacked material. 
       FIG. 3  is a schematic perspective view illustrating the configuration of the screw  41  on the groove forming surface  42  side. In  FIG. 3 , a position of the central axis RX of the screw  41  is indicated by an alternate long and short dash line. As described above, the groove forming surface  42  is provided with the screw grooves  45 . A screw central portion  47 , which is a central portion of the groove forming surface  42  of the screw  41 , is configured as a recess to which one ends of the screw grooves  45  are coupled. The screw central portion  47  faces the communication hole  56  of the barrel  50 . The screw central portion  47  intersects the central axis RX. 
     The screw groove  45  of the screw  41  configures a so-called scroll groove. The screw groove  45  extends in a spiral shape from the screw central portion  47  toward an outer periphery of the screw  41  so as to draw an arc. The screw groove  45  may be configured to extend in an involute curve shape or a spiral shape. The groove forming surface  42  is provided with ridge portions  46  each configuring a side wall portion of the screw groove  45  and extending along the screw groove  45 . The screw groove  45  is continuous to a material introduction port  44  formed on a side surface  43  of the screw  41 . The material introduction port  44  is a portion that receives the material supplied via the supply path  22  of the material accommodation unit  20 . 
       FIG. 3  illustrates an example of the screw  41  including three screw grooves  45  and three ridge portions  46 . The number of the screw grooves  45  and the ridge portions  46  provided in the screw  41  is not limited to three, and only one screw groove  45  may be provided, or two or more screw grooves  45  may be provided. In addition,  FIG. 3  illustrates an example of the screw  41  in which the material introduction ports  44  are formed at three portions. The number of the material introduction ports  44  provided in the screw  41  is not limited to three. The material introduction port  44  may be provided only at one position or may be provided at two or more positions. 
       FIG. 4  is a top view illustrating a configuration of the barrel  50  on a screw facing surface  52  side. As described above, the communication hole  56  is formed in a center of the screw facing surface  52 . A plurality of guide grooves  54  are formed around the communication hole  56  in the screw facing surface  52 . Each of the guide grooves  54  has one end coupled to the communication hole  56 , and the guide grooves  54  extend in a spiral shape from the communication hole  56  toward the outer periphery of the screw facing surface  52 . Each of the guide grooves  54  has a function of guiding the shaping material to the communication hole  56 . One end of the guide groove  54  may not be coupled to the communication hole  56 . The barrel  50  may not be provided with the guide grooves. 
       FIG. 5  is a view illustrating a schematic configuration of the cleaning mechanism  250 . As described above, the cleaning mechanism  250  includes the brush  251  and the blade  252 . The brush  251  is configured by arranging a plurality of hair bundles along the Y direction. The blade  252  is a plate-shaped member along the Z direction and the Y direction. A tip end of the brush  251  and a tip end of the blade  252  are directed in the +Z direction. The tip end of the blade  252  is disposed to be lower than the tip end of the brush  251 . As described above, the brush  251  and the blade  252  are disposed at the height at which the brush  251  and the blade  252  can come into contact with the nozzle  60 . The tip end of the brush  251  is disposed at a height at which the tip end of the brush  251  can come into contact with the shield  68  provided in the nozzle  60 , and the tip end of the blade  252  is disposed at a height at which the tip end of the blade  252  does not come into contact with the shield  68 . In the present embodiment, the brush  251  and the blade  252  are integrated by a fixture  258 , and can be replaced simultaneously at a time of consumption. The brush  251  and the blade  252  may be replaced individually. 
     The brush  251  and the blade  252  have a melting point higher than a plasticizing temperature of a plasticizing material to be plasticized in the injection unit  100 . The brush  251  and the blade  252  have hardness lower than hardness of the nozzle  60 . In the present embodiment, the hardness refers to Vickers hardness. Further, in the present embodiment, an elastic modulus of the blade  252  is higher than an elastic modulus of the brush  251 . In the present embodiment, the elastic modulus refers to a Young&#39;s modulus. The nozzle  60  is formed of, for example, a metal such as a cemented carbide, a tool steel, or SUS, and the brush  251  and the blade  252  are formed of, for example, a metal such as SUS, an iron, or a brass. Each of the brush  251  and the blade  252  may be formed of a resin. Alternatively, the brush  251  may be formed of a natural fiber or a chemical fiber, and the blade  252  may be formed of a ceramic. In another embodiment, the elastic modulus of the blade  252  and the elastic modulus of the brush  251  may be the same, or the elastic modulus of the brush  251  may be higher than the elastic modulus of the blade  252 . 
     The cleaning mechanism  250  further includes a purge portion  253 . The purge portion  253  is also referred to as a purge ledge. In the present embodiment, the purge portion  253 , the blade  252 , and the brush  251  are arranged in this order along a +X direction. That is, the blade  252  is disposed between the purge portion  253  and the brush  251 . A tip end of the purge portion  253  in the +Z direction is lower than the tip end of the blade  252 . On the purge portion  253 , in the cleaning processing to be described later, a waste material injected from the nozzle  60  falls and is collected into a spherical shape on the purge portion  253 , and falls into the purge waste material container  260 . An upper surface of the purge portion  253  is configured as an inclined surface in order to promote the fall of the waste material. More specifically, the purge portion  253  includes a first inclined surface  254 , a second inclined surface  255 , and a third inclined surface  256  in an order of being away from the blade  252  and in an order of descending in position in the vertical direction. The first inclined surface  254 , the second inclined surface  255 , and the third inclined surface  256  are each inclined such that a position of an end portion thereof in the +X direction is higher than a position of an end portion in the −X direction. In the present embodiment, inclination angles of the second inclined surface  255  and the third inclined surface  256  with respect to the horizontal plane are larger than an inclination angle of the first inclined surface  254  with respect to the horizontal plane. 
       FIG. 6  is a flowchart of the three-dimensional shaping processing representing a method for manufacturing a three-dimensional shaped object. The three-dimensional shaping processing is executed when the control unit  300  of the three-dimensional shaping device  10  receives a predetermined operation from the user. 
     In step S 100 , the control unit  300  acquires shaping data from an external computer, a recording medium, or the like. The shaping data includes shaping path data representing a movement path of the nozzle  60  for each layer forming the three-dimensional shaped object. The shaping path data is associated with injection amount data indicating an injection amount of the material to be injected from the nozzle  60 . 
     In step S 110 , the control unit  300  executes the cleaning processing. The cleaning processing is a processing for cleaning the nozzle  60 . Step S 110  in which the cleaning processing is performed and steps S 140  and S 160 , which will be described later, are also referred to as a cleaning step. 
       FIG. 7  is a flowchart of the cleaning processing. When the cleaning processing is performed, in step S 300 , the control unit  300  controls the drive unit  210  to move the nozzle  60  above the purge portion  253 , and then controls the plasticizing mechanism  30  to inject a predetermined amount of material from the nozzle  60  toward the purge portion  253 . The material to be injected toward the purge portion  253  is also referred to as a waste material. The waste material injected onto the purge portion  253  falls into the purge waste material container  260  along the inclined surface of the purge portion  253 . The amount of the material to be injected is, for example, an amount corresponding to a volume of the nozzle flow path  61 . 
     After the waste material is injected on the purge portion  253 , the control unit  300  moves the nozzle  60  toward the brush  251  and the blade  252 , and executes a cleaning operation in step S 310 . The cleaning operation is an operation of bringing at least one of the brush  251  and the blade  252  into contact with the nozzle  60  by reciprocally moving the nozzle  60  such that the nozzle  60  cuts across the cleaning mechanism  250  a plurality of times. 
       FIG. 8  is a diagram illustrating the cleaning operation in the present embodiment.  FIG. 8  illustrates a state in which the tip end of the nozzle  60  and the brush  251  and the blade  252  of the cleaning mechanism  250  are viewed from above, and a path along which the nozzle  60  moves is indicated by a broken line arrow. As illustrated in  FIG. 8 , the cleaning mechanism  250  has a longitudinal direction, and in the present embodiment, the longitudinal direction is the Y direction. In the present embodiment, in the cleaning operation, the control unit  300  brings the tip end of the nozzle  60  into contact with the blade  252 , and then brings the tip end of the nozzle  60  into contact with the brush  251 . Thereafter, the control unit  300  reciprocally moves the nozzle  60  so as to cut across the brush  251  and the blade  252  a plurality of times. Specifically, in the present embodiment, the control unit  300  causes the nozzle  60  to reciprocally move in the longitudinal direction of the cleaning mechanism  250 , along a path having an M shape or a W shape, in other words, a path having a triangular wave shape. In this way, the control unit  300  can reciprocally move the nozzle  60  such that the nozzle  60  comes into contact with the brush  251  or the blade  252  at different positions in the cleaning operation. The control unit  300  may move the nozzle  60  so as to cut across different positions on the cleaning mechanism  250  during all movements in a reciprocating movement, and may move the nozzle  60  so as to cut cross the same position on the cleaning mechanism  250  during a part of the movements in the reciprocating movement. 
     The description will be made with reference to  FIG. 7  again. When the cleaning operation is completed, the control unit  300  counts the number of times of executing the cleaning processing in step S 320 . Hereinafter, the number of times of executing the cleaning processing is also referred to as the number of times of cleaning. The counted number of times of cleaning is stored in a nonvolatile manner in a memory provided in the control unit  300 . In the present embodiment, each time the control unit  300  executes the processing of step S 310  once, the control unit  300  adds the number of times of cleaning once. The number of times of cleaning is continuously added until the cleaning mechanism  250  is replaced, and is reset when the cleaning mechanism  250  is replaced. The control unit  300  may detect the replacement of the cleaning mechanism  250  with a sensor or the like, or may detect the replacement of the cleaning mechanism  250  by receiving a predetermined operation from the user. 
     The description will be made with reference to FIG. again. When the cleaning processing is executed as described above, the control unit  300  subsequently starts executing a stacking processing in step S 120 . This stacking processing is a processing of shaping the three-dimensional shaped object including a plurality of layers by controlling the drive unit  210  and the injection unit  100  in accordance with the shaping data and injecting the shaping material from the injection unit  100  onto the stage  220  for each layer. The processing from step S 120  to step S 150  to be described later is also referred to as a shaping step. 
     During execution of the stacking processing, in step S 130 , the control unit  300  determines whether to execute the cleaning processing. For example, when injection abnormality of the shaping material is detected in the plasticizing mechanism  30 , when a predetermined number of layers are formed, or when a type of the shaping material is to be changed, the control unit  300  determines to execute the cleaning processing. When it is determined to execute the cleaning processing, in step S 140 , the control unit  300  executes the cleaning processing the same as the cleaning processing described with reference to  FIGS. 7 and 8 . When it is determined not to execute the cleaning processing, the control unit  300  skips the cleaning processing in step S 140 . 
     In step S 150 , the control unit  300  determines whether the stacking processing is completed, that is, whether the shaping of the three-dimensional shaped object is completed. If the stacking processing is not completed, the control unit  300  returns the processing to step S 120  and continues the stacking processing. If the stacking processing is completed, in step S 160 , the control unit  300  executes the cleaning processing the same as the cleaning processing described with reference to  FIGS. 7 and 8 . 
     After the cleaning processing in step S 160  is completed, the control unit  300  confirms a wear state of the cleaning mechanism  250  in step S 170 . In the present embodiment, the control unit  300  specifies the wear state of the cleaning mechanism  250  by acquiring the number of times of cleaning counted in step S 320  illustrated in  FIG. 7  from an own memory. In the present embodiment, the number of times of cleaning represents the wear state of the cleaning mechanism  250 . More specifically, the larger the number of times of cleaning is, the larger a wear amount of the cleaning mechanism  250  is. In another embodiment, a wear amount in the cleaning processing of each time may be obtained in advance, and the control unit  300  may calculate the wear amount based on the value and the number of times of cleaning. 
     In step S 180 , the control unit  300  determines whether the wear amount is greater than or equal to a prescribed value based on the wear state of the cleaning mechanism  250 . For example, when the number of times of cleaning exceeds a predetermined threshold value, the control unit  300  determines that the wear amount is equal to or greater than the prescribed value. When it is determined that the wear amount is equal to or greater than the prescribed value, the control unit  300  proposes the replacement of the cleaning mechanism  250  in step S 190 . Specifically, for example, the control unit  300  controls the display device  400  to notify information prompting the replacement of the cleaning mechanism  250 , thereby proposing the replacement of the cleaning mechanism  250 . The control unit  300  may perform notification of the replacement of the cleaning mechanism  250  by outputting sound using a sound output device as the notification unit, or may perform the notification by turning on a light source such as an LED as the notification unit. 
     When it is determined in step S 180  that the wear amount of the cleaning mechanism  250  is not equal to or greater than the prescribed value, the control unit  300  adjusts the height of the cleaning mechanism  250  in step S 200 . Specifically, the control unit  300  controls the height adjustment device  280  to increase the height of the cleaning mechanism  250  as the number of times of cleaning increases, and adjusts an interval between the cleaning mechanism  250  and the nozzle  60 . In the present embodiment, in the height adjustment, the control unit  300  adjusts the interval between the cleaning mechanism  250  and the nozzle  60  such that the brush  251  and the blade  252  have a height that can come into contact with the nozzle  60 , and during the cleaning processing, the tip end of the blade  252  does not come into contact with the shield  68 , and the tip end of the brush  251  can come into contact with the shield  68 . The height adjustment processing of the cleaning mechanism  250  may be executed at a timing at which the execution of a next three-dimensional shaping processing is started. When a series of processings described above is completed, the three-dimensional shaping processing ends. 
     According to the three-dimensional shaping device  10  of the present embodiment described above, the cleaning operation of bringing at least one of the brush  251  and the blade  252  into contact with the nozzle  60  is executed by reciprocally moving the nozzle  60  such that the nozzle  60  cuts across the cleaning mechanism  250  a plurality of times, and in the cleaning operation, the nozzle  60  reciprocally moves such that the nozzle  60  comes into contact with the brush  251  or the blade  252  at the different positions. Therefore, the nozzle  60  can be prevented from intensively cutting across and contacting a specific location of the cleaning mechanism  250 , and thereby the cleaning mechanism  250  can be prevented from being worn at an early stage. As a result, a frequency of the replacement of the cleaning mechanism  250  can be reduced. 
     In the present embodiment, the elastic modulus of the blade  252  provided in the cleaning mechanism  250  is higher than the elastic modulus of the brush  251 . Therefore, it is easy to remove the material adhered to the nozzle  60  by the blade  252 . 
     In the present embodiment, in the cleaning operation, the control unit  300  moves the nozzle  60  in the longitudinal direction of the cleaning mechanism  250 , along the path having a triangular wave shape. Therefore, the nozzle  60  can efficiently cut across the cleaning mechanism  250  at different positions. 
     Further, in the present embodiment, since the tip end of the blade  252  is disposed to be lower than the tip end of the brush  251  in the cleaning mechanism  250 , the material adhered to the tip end of the nozzle  60  can be efficiently removed by the blade  252 . 
     Further, in the present embodiment, since the tip end of the brush  251  is disposed at the height at which the tip end of the brush  251  can come into contact with the shield  68  and the tip end of the blade  252  is disposed at the height at which the tip end of the blade  252  does not come into contact with the shield  68 , the material adhered to the shield  68  can be removed by the brush  251 . 
     Further, in the present embodiment, in the cleaning operation, after bringing the tip end of the nozzle  60  into contact with the blade  252  to remove the shaping material adhered to the tip end of the nozzle  60 , the control unit  300  brings the tip end of the nozzle  60  into contact with the brush  251 , so that the nozzle  60  can be cleaned efficiently. 
     Further, in the present embodiment, in the cleaning processing, the control unit  300  causes the nozzle  60  to move toward the brush  251  and the blade  252  after the waste material is injected from the nozzle  60  on the purge portion  253 , so that the nozzle  60  can be cleaned after removing the shaping material remaining in the nozzle flow path  61 . 
     Further, in the present embodiment, since the control unit  300  specifies the wear state of the cleaning mechanism  250  based on the number of times of executing the cleaning processing, the wear state can be grasped by a simple processing. 
     Further, in the present embodiment, since the control unit  300  proposes the replacement of the cleaning mechanism  250  in accordance with the wear state of the cleaning mechanism  250 , it is possible to improve convenience. 
     Further, in the present embodiment, since the control unit  300  adjusts the interval between the cleaning mechanism  250  and the nozzle  60  in accordance with the wear state of the cleaning mechanism  250 , the nozzle  60  can be cleaned more reliably. 
     In addition, in the present embodiment, since the cleaning processing is executed in three stages of before shaping, during shaping, and after shaping, shaping of the three-dimensional shaped object can be prevented from being performed while the material is adhered to the nozzle  60 . As a result, the resin dust can be prevented from falling from the nozzle  60  onto the three-dimensional shaped object being shaped, and thus a shaping accuracy of the three-dimensional shaped object can be improved. In another embodiment, the cleaning processing may be executed at any one or two timings among three timings of before shaping, during shaping, and after shaping. Further, the control unit  300  may execute the cleaning processing when a predetermined operation from the user is received regardless of these timings. 
       FIGS. 9 to 12  are diagrams each illustrating another example of the cleaning operation.  FIG. 9  illustrates an example in which the nozzle  60  is moved in the longitudinal direction of the cleaning mechanism  250  along a path having a rectangular wave shape.  FIG. 10  illustrates an example in which the nozzle  60  is moved in the longitudinal direction of the cleaning mechanism  250  along a path having a sine wave shape.  FIG. 11  illustrates an example in which the nozzle  60  is moved in the longitudinal direction of the cleaning mechanism  250  along a path having a sawtooth wave shape. As shown in these figures, the control unit  300  can reciprocally move the nozzle  60  along various paths in the cleaning operation. As illustrated in  FIG. 12 , in the cleaning operation, the control unit  300  may set the number of times the nozzle  60  cuts across the brush  251  to be larger than the number of times the nozzle  60  cuts across the blade  252 . In this way, the wear of the blade  252  can be reduced. 
     B. Second Embodiment 
       FIG. 13  is a diagram illustrating a schematic configuration of a three-dimensional shaping device  11  according to a second embodiment. In the present embodiment, the three-dimensional shaping device  11  includes two injection units and two cleaning mechanisms. Specifically, the injection unit in the present embodiment includes a first injection unit  101  provided with a first nozzle  71  through which a first shaping material is to be injected, and a second injection unit  102  provided with a second nozzle  72  through which a second shaping material is to be injected. The first shaping material and the second shaping material can be, for example, a combination of a shaping material and a supporting material, and can also be, for example, a combination of materials of different colors or different materials. Configurations of the first injection unit  101  and the second injection unit  102  are the same as the configuration of the injection unit  100  in the first embodiment. 
     The cleaning mechanism in the present embodiment includes a first cleaning mechanism  261  including a brush and a blade for cleaning the first nozzle  71 , and a second cleaning mechanism  262  including a brush and a blade for cleaning the second nozzle  72 . Configurations of the first cleaning mechanism  261  and the second cleaning mechanism  262  are the same as the configuration of the cleaning mechanism  250  in the first embodiment. In the present embodiment, it is assumed that the two cleaning mechanisms  261  and  262  are disposed at a predetermined interval in the X direction, and the purge portion, the blade, and the brush provided in each of the cleaning mechanisms  261  and  262  are arranged in this order toward the +Y direction. 
     In the present embodiment, the control unit  300  executes the three-dimensional shaping processing illustrated in  FIG. 6  using the two injection units  101  and  102  and the two cleaning mechanisms  261  and  262 . In the three-dimensional shaping processing according to the present embodiment, the two injection units  101  and  102  are selectively used to execute the stacking processing. Then, in the cleaning processing shown in  FIG. 7 , the control unit  300  simultaneously cleans the first nozzle  71  and the second nozzle  72  by using the first cleaning mechanism  261  and the second cleaning mechanism  262  by performing the cleaning operation as shown in  FIG. 8  for the first nozzle  71  provided in the first injection unit  101  and the second nozzle  72  provided in the second injection unit  102 , respectively. 
     According to the second embodiment described above, since the two nozzles  71  and  72  provided in the two injection units  101  and  102  can be simultaneously cleaned, a time required for the cleaning processing can be shortened. As a result, the three-dimensional shaping processing can be efficiently executed. In the present embodiment, an example in which the three-dimensional shaping device  11  is provided with the two injection units and the two cleaning mechanisms is shown, but three or more injection units and three or more cleaning mechanisms may be provided. 
     C. Third Embodiment 
       FIG. 14  is a diagram illustrating a schematic configuration of a three-dimensional shaping device  12  according to a third embodiment. The three-dimensional shaping device  12  of the third embodiment is different from that of the first embodiment mainly in the configuration of the injection unit, and other configurations and processing contents of the three-dimensional shaping processing are the same as those of the first embodiment. Therefore, the configuration of the injection unit will be mainly described below. 
     The three-dimensional shaping device  12  of the present embodiment includes an injection unit  103 , a material accommodation unit  23 , the housing  110 , the drive unit  210 , the stage  220 , and the control unit  300 . The three-dimensional shaping device  12  further includes a blower  16 . The blower  16  is configured as an air blowing device that blows air toward the injection unit  103  via a manifold  17 . In the present embodiment, a part of the manifold  17 , the injection unit  103 , the drive unit  210 , and the stage  220  are accommodated in the shaping space  111  in the housing  110 . 
     The material accommodation unit  23  of the present embodiment is configured as a holder that accommodates a filamentous material. The material accommodation unit  23  is configured to be capable of winding the material accommodated inside to an outside of the material accommodation unit  23 . 
       FIG. 15  is a diagram illustrating a schematic configuration of the injection unit  103  according to the present embodiment. The injection unit  103  includes a heating block  190  including a heater and serving as a plasticizing mechanism provided with a through hole  180 , a nozzle  73  detachably attached to the through hole  180 , and a material transport mechanism  140  that transports a material MF toward a nozzle flow path  74  of the nozzle  73  attached to the heating block  190 . The injection unit  103  is disposed between the material transport mechanism  140  and the heating block  190  in the Z direction, and further includes a shield  92  that prevents heat transfer from the heating block  190  to the material transport mechanism  140 . Different from the first embodiment, the material transport mechanism  140  of the present embodiment includes two wheels  49  instead of including the screw case  31  and the screw  41 . Different from the first embodiment, the heating block  190  does not include the barrel  50  and the case  91 . 
     The nozzle  73  of the present embodiment is attached to the heating block  190  by being inserted, from the −Z direction, into the through hole  180  and a shield opening  93  provided in the shield  92 . That is, in the present embodiment, a dimension of the nozzle  73  along the Z direction and a dimension of the nozzle flow path  74  along the Z direction are larger than a dimension of the through hole  180  along the Z direction. Therefore, in the present embodiment, an inflow port  165  provided at a rear end of the nozzle  73  is located in a +Z direction of the heating block  190 , more specifically, in a +Z direction side of the shield  92 . 
     By the rotation of the two wheels  49  configuring the material transport mechanism  140 , the material MF in the material accommodation unit  23  is drawn to the outside and guided between the two wheels  49 , and is transported toward the nozzle flow path  74  of the nozzle  73  attached to the through hole  180  of the heating block  190 . The heating block  190  plasticizes the material MF transported into the nozzle flow path  74  of the nozzle  73  by heat of a heater (not shown) incorporated in the heating block  190 . 
     In the vicinity of the inflow port  165  of the nozzle  73 , the material MF of the present embodiment is cooled by air sent from the above blower  16  via the manifold  17 . Accordingly, the plasticization of the material MF in the vicinity of the inflow port  165  is prevented, and the material MF is efficiently transported into the inflow port  165 . An outlet end  18  of the manifold  17  is located on the +Z direction side of the shield  92 . Accordingly, the air sent out from the manifold  17  is easily guided to the vicinity of the inflow port  165  by the shield  92 , so that the material MF in the vicinity of the inflow port  165  is efficiently cooled. 
     Although the configuration of the cleaning mechanism  250  in the present embodiment is the same as that of the first embodiment, the tip end of the brush  251  does not come into contact with the shield  92  during the cleaning processing. A reason is that in the present embodiment, the shield  92  is located to be higher than the heating block  190 . 
     In the three-dimensional shaping device  12  of the present embodiment described above, the nozzle  73  can also be cleaned by using the cleaning mechanism  250 . 
     D. Other Embodiments 
     D1. In the above embodiment, the cleaning mechanism  250  includes the purge portion  253 . On the other hand, the cleaning mechanism  250  may not include the purge portion  253 . 
     D2. In the above embodiment, the nozzles  60  and  73  include the shields  68  and  92 . On the other hand, the nozzles  60  and  73  may not include the shields  68  and  92 . 
     D3. In the above embodiment, the control unit  300  may separately confirm the wear states of the blade  252  and the brush  251 , and may individually propose the replacement. More specifically, the control unit  300  separately counts the number of times the nozzle  60  passes through the blade  252  and the brush  251 , and stores the number of times of cleaning in the memory, respectively. Then, the control unit  300  compares the threshold values, which are respectively set for the blade  252  and the brush  251 , with the respective numbers of times of cleaning. In this way, the control unit  300  can separately propose the replacement for the blade  252  and the brush  251 . 
     D4. In the above embodiment, the counting of the number of times of cleaning, the detecting of the wear amount and the proposal of replacement of the cleaning mechanism may not be executed. That is, the processings of steps S 170  to S 190  in  FIG. 6  may be omitted. 
     D5. In the above embodiment, the interval between the nozzle  60  and the cleaning mechanism  250  is adjusted by using the height adjustment device  280 . On the other hand, for example, if the drive unit  210  is capable of moving the injection unit  100  along the Z direction, the control unit  300  may adjust the interval between the nozzle  60  and the cleaning mechanism  250  during the cleaning processing by adjusting the height of the injection unit  100 . 
     D6. In the above embodiment, height adjustment of the cleaning mechanism  250  based on the height adjustment device  280  may be omitted. That is, the processing of step S 200  in  FIG. 6  may be omitted. In this case, the cleaning mechanism  250  may be directly fixed to the housing  110  instead of the height adjustment device  280 . 
     D7. In the above embodiment, the wear state of the cleaning mechanism  250  is determined based on the number of times of cleaning. On the other hand, for example, a distance measuring sensor capable of detecting the height of the blade  252  or the brush  251  may be provided in the housing  110 , and the wear state of the cleaning mechanism may be determined based on a measurement result of the height of the blade  252  or the brush  251  based on the sensor. In this case, the lower the height of the blade  252  or the brush  251  is, the greater the wear amount is. 
     D8. In the above embodiment, the cleaning mechanism  250  is fixed to the housing  110  via the height adjustment device  280 . On the other hand, the cleaning mechanism  250  may be fixed to the stage  220 . If the cleaning mechanism  250  is fixed to the stage  220 , the control unit  300  can adjust the interval between the cleaning mechanism  250  and the nozzle  60  during the cleaning processing using the second drive unit  212 . 
     D9. In the above embodiment, the cleaning mechanism  250  is disposed in a region different from the stage  220  in the horizontal direction. On the other hand, the cleaning mechanism  250  may be disposed in a region which overlaps the stage  220  in the horizontal direction and which is different from a shaping region of the stage  220  on which the three-dimensional shaped object is to be shaped. Accordingly, a compact three-dimensional shaping device can be obtained. 
     E. Other Embodiments 
     The present disclosure is not limited to the above embodiments, and can be implemented by various configurations without departing from the gist of the present disclosure. For example, in order to solve a part or all of problems described above, or to achieve a part or all of effects described above, technical characteristics in the embodiments corresponding to technical characteristics in aspects to be described below can be replaced or combined as appropriate. Further, when the technical features are not described as essential in the present description, the technical features can be appropriately deleted. 
     1. According to a first aspect of the present disclosure, a three-dimensional shaping device is provided. The three-dimensional shaping device includes: an injection unit including a plasticizing mechanism configured to plasticize a plasticizing material to generate a shaping material and a nozzle, and configured to inject the shaping material from the nozzle; a stage on which the shaping material is to be stacked; a drive unit configured to change a relative position between the injection unit and the stage; a cleaning mechanism including a brush and a blade; and a control unit configured to execute a cleaning processing for cleaning the nozzle, in which the brush and the blade are disposed at a height at which the brush and the blade are able to come into contact with the nozzle, the brush and the blade have a melting point higher than a plasticizing temperature of the plasticizing material, and have hardness lower than hardness of the nozzle, in the cleaning processing, the control unit is configured to execute a cleaning operation of bringing at least one of the brush and the blade into contact with the nozzle by reciprocally moving the nozzle such that the nozzle cuts across the cleaning mechanism a plurality of times, and the control unit is configured to reciprocally move the nozzle such that the nozzle comes into contact with the brush or the blade at different positions in the cleaning operation. 
     In such an aspect, the cleaning operation of bringing at least one of the brush and the blade into contact with the nozzle is executed by reciprocally moving the nozzle such that the nozzle cuts across the cleaning mechanism a plurality of times, and in the cleaning operation, the nozzle is reciprocally moved such that the nozzle comes into contact with the brush or the blade at the different positions. Therefore, the nozzle can be prevented from intensively cutting across a specific location of the cleaning mechanism, and thereby the cleaning mechanism can be prevented from being worn at an early stage. As a result, a frequency of the replacement of the cleaning mechanism can be reduced. 
     2. In the above aspect, an elastic modulus of the blade may be higher than an elastic modulus of the brush. In such an aspect, the material adhered to the nozzle can be easily removed by the blade. 
     3. In the above aspect, in the cleaning operation, the control unit may be configured to reciprocally move the nozzle in a longitudinal direction of the cleaning mechanism along a path having a triangular wave shape, a rectangular wave shape, a sine wave shape, or a sawtooth wave shape. In such an aspect, the nozzle can efficiently cut across the cleaning mechanism at different positions. 
     4. In the above aspect, a tip end of the blade may be disposed to be lower than a tip end of the brush. In such an aspect, the material adhered to the tip end of the nozzle can be efficiently removed by the blade. 
     5. In the above aspect, the nozzle may include a shield above a tip end of the nozzle, the tip end of the brush may be disposed at a height at which the tip end of the brush is able to come into contact with the shield, and the tip end of the blade may be disposed at a height at which the tip end of the blade does not come into contact with the shield. In such an aspect, the material adhered to the shield can be removed. 
     6. In the above aspect, in the cleaning operation, the control unit may be configured to bring the tip end of the nozzle into contact with the blade, and then bring the tip end of the nozzle into contact with the brush. In such an aspect, an entire nozzle can be cleaned by the brush after the material adhered to the tip end of the nozzle is removed by the blade. Therefore, the nozzle can be cleaned efficiently. 
     7. In the above aspect, in the cleaning operation, the control unit may be configured to set the number of times the nozzle cuts across the brush to be larger than the number of times the nozzle cuts across the blade. In such an aspect, the wear of the blade can be reduced. 
     8. In the above aspect, the cleaning mechanism may include a purge portion, the blade may be disposed between the purge portion and the brush, and the purge portion may include a first inclined surface, a second inclined surface, and a third inclined surface in an order of being away from the blade and in an order of descending in position in a vertical direction, and inclination angles of the second inclined surface and the third inclined surface with respect to a horizontal plane may both be larger than an inclination angle of the first inclined surface with respect to the horizontal plane. 
     9. In the above aspect, in the cleaning processing, the nozzle may be moved toward the brush and the blade after the shaping material is injected from the nozzle on the purge portion. In such an aspect, the nozzle can be cleaned after the material remaining in the nozzle is removed. 
     10. In the above aspect, the injection unit may include a first injection unit provided with a first nozzle through which a first shaping material is to be injected, and a second injection unit provided with a second nozzle through which a second shaping material is to be injected, the cleaning mechanism may include a first cleaning mechanism including a brush and a blade for cleaning the first nozzle, and a second cleaning mechanism including a brush and a blade for cleaning the second nozzle, and the control unit may be configured to simultaneously execute the cleaning processing on the first nozzle and the second nozzle using the first cleaning mechanism and the second cleaning mechanism. In such an aspect, since the nozzles provided in the two injection units can be simultaneously cleaned, a time required for the cleaning processing can be shortened. 
     11. In the above aspect, the control unit may be configured to specify a wear state of the cleaning mechanism based on the number of times of executing the cleaning processing. In such an aspect, the wear state can be grasped by a simple processing. 
     12. In the above aspect, the three-dimensional shaping device may further include: a notification unit, and the control unit may be configured to control the notification unit in accordance with the wear state to notify information of prompting replacement of the cleaning mechanism. In such an aspect, convenience of the three-dimensional shaping device can be improved. 
     13. In the above aspect, the control unit may be configured to adjust an interval between the cleaning mechanism and the nozzle in accordance with the wear state. In such an aspect, the nozzle can be cleaned more reliably. 
     14. According to a second aspect of the present disclosure, there is provided a method for manufacturing a three-dimensional shaped object in a three-dimensional shaping device, the three-dimensional shaping device including: an injection unit including a plasticizing mechanism configured to plasticize a plasticizing material to generate a shaping material and a nozzle, and configured to inject the shaping material from the nozzle; a stage on which the shaping material is to be stacked; a drive unit configured to change a relative position between the injection unit and the stage; and a cleaning mechanism including a brush and a blade, in which the brush and the blade are disposed at a height at which the brush and the blade are able to come into contact with the nozzle, and the brush and the blade have a melting point higher than a plasticizing temperature of the plasticizing material, and have hardness lower than hardness of the nozzle. This manufacturing method includes a shaping step of shaping a three-dimensional shaped object by injecting a shaping material from the injection unit to the stage; and a cleaning step of executing a cleaning operation of bringing at least one of the brush and the blade into contact with the nozzle by reciprocally moving the nozzle such that the nozzle cuts across the cleaning mechanism a plurality of times at any one timing of before the shaping step, during the shaping step and after the shaping step, in which in the cleaning step, the nozzle is reciprocally moved such that the nozzle comes into contact with the brush or the blade at different positions in the cleaning operation.