JP7058141B2 - Modeling equipment, modeling method and modeling system - Google Patents

Description

The present invention relates to a modeling device, a modeling method, and a modeling system.

3D printers are becoming widespread as a device capable of producing a wide variety of small quantities of shaped objects without using a mold or the like. 3D printers that use the fused deposition modeling method (hereinafter abbreviated as FFF (Fused Filament Fabrication)) have been becoming cheaper in recent years, and have become widespread for consumers.

In such a 3D printer, a technique for preventing a decrease in strength in the stacking direction of a three-dimensional model has been studied. For example, Patent Document 1 discloses a technique for providing a technique for extruding and laminating a molten resin, which can sufficiently secure the welding strength between layers. In Patent Document 1, the molten resin extrusion laminating device is a device for laminating in multiple stages while extruding the molten resin, and includes a discharge unit that extrudes the molten resin, a heating unit that heats the resin material that has already been extruded, and the like. A device having a controller for controlling the operation of the discharge unit and the heating unit is disclosed. The controller controls the heating unit to heat the resin material forming the layer of the previous stage when extruding the molten resin from the discharge unit to form the layer of one stage.

However, in the prior art, remelting in order to increase the adhesiveness between the layers of the modeling material is not sufficient in that it takes a long time for modeling.

The modeling apparatus according to the present disclosure includes a heating means for heating a first modeling material layer formed of a modeling material, a temperature detecting means for detecting the temperature of the first modeling material layer, and a heated first modeling. It has a discharge means for discharging the molten modeling material to the material layer and laminating a second modeling material layer. The modeling apparatus further has a changing means for changing the modeling parameters based on the temperature detected by the temperature detecting means when modeling the second modeling material layer.

According to the above configuration, it is possible to perform modeling by adjusting the modeling parameter so that the modeling time is shortened while improving the adhesiveness between the layers of the modeling material.

It is a schematic diagram which shows the structure of the 3D modeling apparatus which concerns on one Embodiment. It is a schematic diagram which shows the cross section of the discharge module in the 3D modeling apparatus of FIG. It is a hardware block diagram of the 3D modeling apparatus which concerns on one Embodiment. It is a schematic diagram which shows an example of the operation of heating the lower layer. It is a top view which looked at the heating module in one Embodiment from the modeling table side. It is a schematic diagram which shows the state of a modeled object at the time of forming an upper layer. It is a schematic diagram which shows the state of a modeled object at the time of forming an upper layer. It is a schematic diagram which shows the state of a modeled object at the time of forming an upper layer. It is a schematic diagram which shows the state of a modeled object at the time of forming an upper layer. It is a schematic diagram which shows an example of the reheating range in this embodiment. It is a schematic diagram which shows the other example of the reheating range in this embodiment. It is a functional block diagram related to the change of the modeling parameter at the time of remelting of the three-dimensional modeling apparatus according to one embodiment. It is a schematic diagram explaining the preferable temperature condition of reheating. It is a schematic diagram explaining the method for adjusting the heating amount when the laser apparatus is used as a heating means. It is a flow chart which shows the modeling process which concerns on one Embodiment. It is a flow chart which shows the lower layer remelting and the upper layer modeling process which concerns on one Embodiment. It is a flow chart which shows the lower layer remelting and the upper layer modeling which concerns on other embodiment. It is a schematic diagram which shows the operation of the lower layer heating in one Embodiment. It is a schematic diagram which shows the operation of the lower layer heating in one Embodiment. It is a schematic diagram which shows the operation of the lower layer heating in one Embodiment. It is a schematic diagram which shows the operation of the lower layer heating in one Embodiment. It is sectional drawing which shows an example of the filament which made the material composition unevenly distributed. FIG. 22 is a cross-sectional view of the ejected material of the filament of FIG. 22. It is sectional drawing of the modeled object which is modeled using the filament of FIG. It is a schematic diagram which shows an example of the 3D modeling apparatus which has a regulation means. It is a flow figure which shows an example of the process which regulates the direction of a filament. It is a schematic diagram which shows the modeling and surface treatment operation in one Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<<< Overall configuration >>>
As an embodiment of the present invention, a three-dimensional modeling apparatus for modeling a three-dimensional model by the Fused Deposition Modeling Method (FFF) will be described. The three-dimensional modeling apparatus in the present embodiment is not limited to the one using the Fused Deposition Modeling Method (FFF), and the three-dimensional model is laminated on the mounting surface of the mounting table by a modeling means. Any modeling method may be used for modeling.

FIG. 1 is a schematic diagram showing a configuration of a three-dimensional modeling apparatus according to an embodiment. FIG. 2 is a schematic view showing a cross section of a discharge module in the three-dimensional modeling apparatus of FIG. The three-dimensional modeling apparatus 1 can form a three-dimensional modeled object whose mold becomes complicated or cannot be molded by injection molding.

The inside of the housing 2 in the three-dimensional modeling apparatus 1 is a processing space for modeling the three-dimensional model M. A modeling table 3 as a mounting table is provided inside the housing 2, and a three-dimensional modeled object M is modeled on the modeling table 3.

For modeling, a long filament F made of a resin composition using a thermoplastic resin as a matrix is used. The filament F is an elongated wire-shaped solid material, and is set on a reel 4 outside the housing 2 in the three-dimensional modeling apparatus 1 in a wound state. The reel 4 rotates by being pulled by the rotation of the extruder 11, which is the driving means of the filament F, without exerting a large resistance force.

A discharge module 10 (modeling head) as a modeling material discharge member is provided above the modeling table 3 inside the housing 2. The discharge module 10 is modularized by an extruder 11, a cooling block 12, a filament guide 14, a heating block 15, a discharge nozzle 18, an image pickup module 101, a torsion rotation mechanism 102, and other components. The filament F is pulled in by the extruder 11 and is supplied to the discharge module 10 of the three-dimensional modeling apparatus 1.

The image pickup module 101 captures a 360 ° image of the filament F drawn into the ejection module 10, that is, an omnidirectional image of a portion of the filament F. Although the ejection module of FIG. 2 is provided with two image pickup modules, for example, a 360 ° image of the filament F may be imaged by one image pickup module 101 by using a reflector or the like. As the image pickup module 101, a camera including an image pickup optical system such as a lens and an image pickup element such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor is exemplified.

The torsional rotation mechanism 102 is constructed by a roller, and regulates the direction of the filament F by rotating the filament F drawn into the discharge module 10 in the width direction. When the diameter measuring unit 103 measures the width between the edges of the filaments in the two directions of the X-axis and the Y-axis as the diameter from the image of the filament imaged by the imaging module 101, and detects a nonstandard diameter, the diameter measuring unit 103 measures the diameter. Output error information. The output destination of the error information may be a display, a speaker, or another device. The diameter measuring unit 103 may be a circuit or a function realized by processing by a CPU.

The heating block 15 has a heat source 16 such as a heater and a thermocouple 17 for controlling the temperature of the heater, and the filament F supplied to the discharge module 10 is heated and melted via a transfer path. It is supplied to the discharge nozzle 18.

The cooling block 12 is provided on the upper part of the heating block 15. The cooling block 12 has a cooling source 13 to cool the filament. As a result, the cooling block 12 prevents the molten filament FM from flowing back to the upper part in the discharge module 10, increasing the resistance to push out the filament, or preventing clogging in the transfer path due to the solidification of the filament. A filament guide 14 is provided between the heating block 15 and the cooling block 12.

As shown in FIGS. 1 and 2, a discharge nozzle 18 for discharging the filament F, which is a modeling material, is provided at the lower end of the discharge module 10. The discharge nozzle 18 discharges the molten or semi-melted filament FM supplied from the heating block 15 so as to be linearly extruded onto the modeling table 3. The discharged filament FM is cooled and solidified to form a layer having a predetermined shape. Further, the discharge nozzle 18 stacks and stacks new layers by repeating the operation of ejecting the molten or semi-melted filament FM into the formed layer in a linear manner. As a result, a three-dimensional model can be obtained.

In this embodiment, the discharge module 10 is provided with two discharge nozzles. The first discharge nozzle melts and discharges the filament of the model material constituting the three-dimensional model, and the second discharge nozzle melts and discharges the filament of the support material. In FIG. 1, the second discharge nozzle is arranged behind the first discharge nozzle. The number of discharge nozzles is not limited to two and is arbitrary.

The support material discharged from the second discharge nozzle is usually a material different from the model material constituting the three-dimensional model. The support portion formed by the support material is finally removed from the model portion formed by the model material. The filament of the support material and the filament of the model material are each melted in the heating block 15, discharged so as to be extruded from the respective ejection nozzles 18, and sequentially laminated in layers.

Further, the three-dimensional modeling apparatus 1 is provided with a heating module 20 that heats the lower layer of the layer being formed by the discharge module 10. The heating module is provided with a laser light source 21 for irradiating a laser. The laser light source 21 irradiates the laser at a position in the lower layer immediately before the filament FM is ejected. The laser light source is not particularly limited, but a semiconductor laser is exemplified, and the irradiation wavelength of the laser is exemplified by 445 nm.

The discharge module 10 and the heating module 20 are held so as to be slidable with respect to the X-axis drive shaft 31 (X-axis direction) extending in the left-right direction of the device (left-right direction = X-axis direction in FIG. 1) via a connecting member. Has been done. The discharge module 10 can be moved in the left-right direction (X-axis direction) of the device by the driving force of the X-axis drive motor 32.

The X-axis drive motor 32 is held so as to be slidable along a Y-axis drive axis (Y-axis direction) extending in the front-rear direction of the device (depth direction = Y-axis direction in FIG. 1). When the X-axis drive shaft 31 moves along the Y-axis direction by the driving force of the Y-axis drive motor 33 together with the X-axis drive motor 32, the discharge module 10 and the heating module 20 move in the Y-axis direction.

On the other hand, the modeling table 3 is passed through the Z-axis drive shaft 34 and the guide shaft 35, and can move along the Z-axis drive shaft 34 extending in the vertical direction of the device (vertical direction in FIG. 1 = Z-axis direction). It is being held. The modeling table 3 moves in the vertical direction (Z-axis direction) of the device by the driving force of the Z-axis drive motor 36. The modeling table 3 may be provided with a heating unit for heating the loaded model.

If the melt discharge of the filament is continued over time, the peripheral portion of the discharge nozzle 18 may be contaminated with the melted resin. On the other hand, the cleaning brush 37 provided in the three-dimensional modeling apparatus 1 periodically performs a cleaning operation on the peripheral portion of the discharge nozzle 18 to prevent the resin from sticking to the tip of the discharge nozzle 18. Can be done. Preferably, the cleaning operation is performed before the temperature of the resin is completely lowered from the viewpoint of preventing sticking. In this case, the cleaning brush 37 is preferably made of a heat-resistant member. The polishing powder generated during the cleaning operation may be accumulated in the dust box 38 provided in the three-dimensional modeling apparatus 1 and discarded periodically, or may be provided with a suction path and discharged to the outside.

FIG. 3 is a hardware configuration diagram of the three-dimensional modeling apparatus according to the embodiment. The three-dimensional modeling device 1 has a control unit 100. The control unit 100 is constructed by a CPU (Central Processing Unit), a circuit, or the like, and is electrically connected to each unit as shown in FIG.

The three-dimensional modeling device 1 is provided with an X-axis coordinate detection mechanism that detects the position of the discharge module 10 in the X-axis direction. The detection result of the X-axis coordinate detection mechanism is sent to the control unit 100. The control unit 100 controls the drive of the X-axis drive motor 32 based on the detection result, and moves the discharge module 10 to the target X-axis direction position.

The three-dimensional modeling device 1 is provided with a Y-axis coordinate detection mechanism that detects the position of the discharge module 10 in the Y-axis direction. The detection result of the Y-axis coordinate detection mechanism is sent to the control unit 100. The control unit 100 controls the drive of the Y-axis drive motor 33 based on the detection result, and moves the discharge module 10 to the target Y-axis direction position.

The three-dimensional modeling apparatus 1 is provided with a Z-axis coordinate detection mechanism that detects the position of the modeling table 3 in the Z-axis direction. The detection result of the Z-axis coordinate detection mechanism is sent to the control unit 100. The control unit 100 controls the drive of the Z-axis drive motor 36 based on the detection result, and moves the modeling table 3 to the target Z-axis direction position.

In this way, the control unit 100 moves the relative three-dimensional positions of the discharge module 10 and the modeling table 3 to the target three-dimensional positions by controlling the movement of the discharge module 10 and the modeling table 3.

Further, the control unit 100 includes an extruder 11, a cooling block 12, a discharge nozzle 18, a laser light source 21, a cleaning brush 37, a rotation stage RS, an image pickup module 101, a torsion rotation mechanism 102, a diameter measurement unit 103, and a temperature sensor 104. These drives are controlled by transmitting control signals to the drive unit. The rotation stage RS, the side cooling unit 39, the image pickup module 101, the torsion rotation mechanism 102, the diameter measurement unit 103, and the temperature sensor 104 will be described later.

<< Heating method >>
FIG. 4 is a schematic diagram showing an example of an operation of heating the lower layer. Hereinafter, as one embodiment, a method of heating using a laser will be described.

During the modeling of the upper layer by the ejection module 10, the laser light source 21 irradiates the position of the lower layer immediately before the filament FM is ejected with the laser to reheat. Reheating means that the molten filament FM is cooled and solidified, and then heated again. The temperature of the reheating is not particularly limited, but is preferably higher than the temperature at which the filament FM of the lower layer melts.

The lower layer temperature before heating is sensed by the temperature sensor 104. The position of the temperature sensor 104 is arranged at an arbitrary position where the lower surface before heating can be sensed. In this embodiment, in FIG. 4, the temperature sensor 104 is arranged behind the laser light source 21. By sensing the temperature of the lower layer before heating with the temperature sensor 104 and adjusting the output of the laser based on the sensing result, the lower layer can be reheated to a predetermined temperature or higher. Alternatively, the temperature of the lower layer during reheating may be sensed by the temperature sensor 104, and energy may be input from the laser to the lower layer until the sensing result becomes an arbitrary temperature or higher. In that case, the position of the temperature sensor 104 is arranged at an arbitrary position where the heating surface can be sensed. As the temperature sensor 104, any known device may be used, and it may be a contact type or a non-contact type.

By reheating the surface of the lower layer, the temperature difference between the lower layer and the filament FM discharged to the surface of the lower layer becomes smaller, and the lower layer and the discharged filament are mixed to improve the adhesiveness in the stacking direction. ..

FIG. 5 is a plan view of the heating module in one embodiment as viewed from the modeling table 3 side. In FIG. 5, the heating module 20 is attached to the rotary stage RS. The rotary stage RS rotates around the discharge nozzle 18. The laser light source 21 rotates and moves with the rotation of the rotation stage RS. As a result, the laser light source 21 can irradiate the laser beam ahead of the ejection position by the ejection nozzle 18 even if the moving direction of the ejection nozzle 18 changes.

FIG. 6 is a schematic view showing the state of the modeled object at the time of forming the upper layer. Hereinafter, the layer being modeled by the discharge module 10 is referred to as an upper layer Ln, the layer immediately below the layer being modeled is referred to as a lower layer Ln-1, and the layer immediately below the lower layer Ln-1 is referred to as a lower layer Ln-2. The arrow in FIG. 6 indicates the movement path (tool path) of the discharge module. In FIGS. 6 and 6 and subsequent sections, the ejected filaments are represented by elliptical columns so that the tool path of the ejection module can be understood. For this reason, voids are formed between the filaments, but in reality, it is preferable to form the filament so that the voids are not formed in terms of strength.

FIG. 6A is a schematic view showing a modeled object when the upper layer is formed without reheating the lower layer. When the upper layer Ln is formed without reheating the lower layer Ln-1, the upper layer Ln can be formed in a state where the lower layer Ln-1 is solidified, so that the deformation of the outer surface OS does not occur. However, in this case, sufficient adhesive strength cannot be obtained between the upper layer Ln and the lower layer Ln-1.

FIG. 6B is a schematic view showing a modeled object when forming an upper layer while reheating the lower layer. When the upper layer Ln is formed while reheating the lower layer Ln-1, the outer surface OS is deformed because the upper layer Ln can be formed in the state where the lower layer Ln-1 is melted.

FIG. 6C is a schematic view showing a modeled object when forming an upper layer while reheating the lower layer. In the example of FIG. 6C, even if the upper layer Ln is formed while reheating the lower layer Ln-1 of the model portion M, the model portion M is supported by the support portion S, so that the outer surface of the model portion M is formed. The OS does not deform.

In the present embodiment, the upper Ln layer is formed in a state where the lower Ln-1 is partially remelted. As a result, the entanglement of the polymer between the upper layer Ln and the lower layer Ln-1 is promoted, and the strength of the modeled object is improved. Further, by appropriately setting the conditions for remelting, it is possible to achieve both shape accuracy and strength in the stacking direction of the model portion. Hereinafter, an example of setting the remelting region and its effect in the present embodiment will be described.

The model material and the support material may be the same material or may be different. For example, even when the model portion M and the support portion S are made of the same material, they can be separated after modeling by controlling the strength of these interfaces.

FIG. 7 is a schematic view showing the state of the modeled object at the time of forming the upper layer. In the modeling method of FIG. 7A, the three-dimensional modeling apparatus 1 reheats the surface of the model portion M in the lower layer Ln-1 and the surface of the support portion S excluding the outer peripheral portion to form the remelted portion RM. Then, the upper layer Ln is formed. According to this method, since the region on the outer surface OS side of the model portion M is remelted for modeling, the adhesiveness between the layers is improved and the strength in the stacking direction is improved. Further, by melting the outer surface OS side, peeling of the support portion S and the model portion M during modeling is less likely to occur, and the modeling accuracy is improved. However, if the adhesiveness between the support portion S and the model portion M becomes too high, the releasability of the support portion S after modeling deteriorates. Further, depending on the heating temperature, the strength of the model unit M may be reduced by mixing the support unit S with the model unit M. Mixing of materials can be prevented by using a method of heating the laminated surface by non-contact, or by devising the movement of the contact member or cleaning the contact member when heating by contact. be able to. Further, the releasability of the support portion S is improved by using a material different from the model material as the support material and having a melting point lower than that of the model material.

In the modeling method of FIG. 7B, the three-dimensional modeling apparatus 1 forms the support portion S by using the model material and the support material. In this case, the three-dimensional modeling apparatus 1 arranges the support material in the region Ss on the model unit M side in the support unit S, and arranges the model material in the region Sm on the outer peripheral side. In this case, the three-dimensional modeling apparatus 1 may be modeled by forming a region Sm in the model unit M and the support unit S from the model material, and then pouring the support material into the gap of the model material. Subsequently, the three-dimensional modeling apparatus 1 forms the upper layer Ln while reheating the surface of the model portion M in the lower layer Ln-1 and the surface excluding the outer peripheral portion of the support portion S.

The modeling method of FIG. 7B is suitable when the support portion S is excellent in releasability. Further, the modeling method of FIG. 7B is in that even when the shape accuracy of the region Ss and the strength as a structure are low, the region Sm supports the region Ss to supplement the shape accuracy and strength of the region Ss. preferable.

In the modeling method (C) of FIG. 7, the three-dimensional modeling apparatus 1 forms the upper layer Ln while reheating the surface of the model unit M except for the vicinity of the outer surface OS. According to this method, the heat of the model portion M is not easily transferred to the support portion S at the time of remelting, so that the shape of the support portion S is stable. The modeling method (C) of FIG. 7 is effective in that the shape of the model portion M can be easily maintained and the releasability between the model portion M and the support portion S can be easily ensured. Compared with the molding method in which the whole is remelted, the strength in the stacking direction is weakened. Therefore, the modeling method (C) of FIG. 7 is effective when modeling a modeled object having a strong internal structure or when focusing on modeling accuracy and releasability.

FIG. 8 is a schematic view showing the state of the modeled object at the time of forming the upper layer. In the modeling method of FIG. 8A, the non-remelting region on the surface of the model portion M is expanded to a position farther from the outer surface OS, and the remelting portion RM is made smaller. It is different from the modeling method of. According to the modeling method of FIG. 8A, the shape of the support portion S is more stable than that of the modeling method of FIG. 7C, so that it is more effective in that the shape of the model portion M can be maintained. On the other hand, the strength in the stacking direction in the model portion M becomes smaller.

The modeling method of FIG. 8B is different from the modeling method of FIG. 7C in that the surface of the lower layer Ln-1 is reheated to the vicinity of the outer surface OS in the model portion M. The modeling method (B) of FIG. 8 is effective when the melting point of the support material is higher than that of the model material. According to the modeling method of FIG. 8B, the strength in the stacking direction in the model portion M is higher than that of the modeling method of FIG. 7C.

In the modeling method of FIG. 8C, the three-dimensional modeling apparatus 1 first discharges the support material of the upper layer Ln to form the support portion S, and then remelts the model portion M of the lower layer Ln-1. Therefore, the model portion M of the upper layer Ln is formed. Since the support portion S is finally removed after modeling, it is sufficient that the support portion S has a strength that does not peel off during modeling, and is not required to have the strength of the model material. Therefore, as the support material, it is preferable to select a model material that can be laminated with higher accuracy. By forming the support portion S of the upper layer Ln in a state where the lower layer Ln-1 is solidified, the modeling accuracy of the support portion S is improved. According to the modeling method of FIG. 8C, the support portion S and the model portion M are formed independently. Therefore, in the three-dimensional modeling apparatus 1, the stacking pitch of the support portion S can be made finer than the stacking pitch of the model portion M. For example, in the configuration of FIG. 8C, the stacking pitch of the support portion is 1/2 of the stacking pitch of the model portion M. Since the melted model material follows the shape of the support portion S, the outer surface OS of the model portion M becomes smoother by making the stacking pitch of the support portion S finer. When the support unit S can be modeled more accurately than the model unit M, the method (C) in FIG. 8 is suitable.

FIG. 9 is a schematic view showing the state of the modeled object at the time of forming the upper layer. The modeling method of FIG. 9A is different from that of FIG. 8B in that the support portion S in the upper layer Ln is first formed and then the model portion M in the upper layer Ln is formed. When the melting point of the support material is higher than that of the model material, the support portion S does not melt even when heated to the vicinity of the outer surface OS in the model portion M. According to the modeling method (A) of FIG. 9, a modeled product having excellent releasability and high strength in the stacking direction can be obtained, and the modeling accuracy is improved.

The modeling method of FIG. 9B differs from the method of FIG. 7 in that the support portion S in the upper layer Ln is first formed and then the model portion M in the upper layer Ln is formed. According to the method (B) of FIG. 9, even when the shape accuracy of the region Ss and the strength as a structure are low, the region Sm supports the region Ss to improve the shape accuracy of the region Ss and the strength as a structure. I can make up for it. However, according to the modeling method of FIG. 9B, if the region Ss melts during remelting, the releasability of the support portion S may decrease.

The modeling method of FIG. 9 (C) is different from that of FIG. 8 (A) in that the outer peripheral side of the model portion M in the upper layer Ln is first formed and then the remaining portion of the model portion M in the upper layer is formed. .. According to the modeling method (C) of FIG. 9, since modeling is performed only by the model portion M, the shape is stable and the modeling accuracy is improved. Further, since the modeling is performed while remelting a part of the side surface of the model portion M in the upper layer Ln, the strength of the model portion M is also improved.

FIG. 10 is a schematic diagram showing an example of the reheating range in the present embodiment. The three-dimensional modeling apparatus 1 is laminated while maintaining the shape of the modeled object by intentionally narrowing the remelted portion RM without reheating the outer peripheral portion of the three-dimensional modeled object M for the purpose of maintaining the outer shape. Improves adhesion between. Note that FIG. 10 does not show the shape of the filament, but only the shape of the modeled object. Further, the modeled object shown in FIG. 10 is typically a model material. As shown in FIG. 10, by intentionally narrowing the remelted portion RM, the adhesion between the laminates can be improved inside, but the outer shape of the three-dimensional model M is not disturbed, so that the modeling quality is not disturbed. Can be maintained.

On the other hand, if the remelted portion RM is intentionally narrowed as shown in FIG. 10, the shape of the three-dimensional model M can be maintained, but the outer peripheral portion is not remelted, so that the adhesion between the laminates in the outer peripheral portion is adhered. There is a possibility that the improvement of sex cannot be achieved sufficiently.

FIG. 11 is a schematic diagram showing another example of the reheating range in the present embodiment. Note that also in FIG. 11, as in FIG. 10, the shape of the filament is not shown, only the shape of the modeled object is shown, and the modeled object shown in FIG. 11 is typically a model material. Please note. The three-dimensional modeling apparatus 1 reheats the three-dimensional model M including the outer peripheral portion of the three-dimensional model M for the purpose of improving the strength of the outer peripheral portion of the shape of the three-dimensional model M, and expands the remelted portion RM as much as possible. Can be done. This makes it possible to improve the adhesion between the laminates including the outer peripheral portion. In this case, there is a possibility that the molding disorder may occur due to the remelting of the outer peripheral portion. However, since the strength of the outer peripheral portion is improved, even if the shape is disturbed, it is possible to deal with it by secondary processing.

As described above, by setting an appropriate reheating range and performing remelting, it is possible to improve the laminated strength of the modeled object and the modeling quality. However, in such a configuration, in order to remelt the lower layer, it is necessary to raise the temperature to the temperature at which the lower layer is remelted by a heating means such as a laser device. For this reason, it is necessary to wait for modeling until the temperature rises, or to change the speed to perform ejection while irradiating the laser, which may increase the time required for modeling.

<< Functional block >>
Hereinafter, with reference to FIG. 12, the configuration of the three-dimensional modeling apparatus 1 for achieving both improvement of the laminated strength of the modeled object and reduction of the modeling time will be described in more detail.

FIG. 12 is a diagram illustrating a functional block of the control unit 100 together with peripheral components. In addition, in FIG. 12, as peripheral components of the control unit 100, a discharge module 10 including a discharge nozzle 18, a heating module 20 including a rotary stage RS and a laser light source 21, an X-axis drive motor 32, and a Y-axis drive motor are shown. 33 and the temperature sensor 104 are shown.

The control unit 100 according to the present embodiment is for the heating control unit 110 that controls reheating by the heating module 20, the modeling control unit 120 that controls the modeling operation by the discharge module 10, the heating control unit 110, and the modeling control unit 120. , A modeling parameter changing unit 130 for setting while appropriately changing the modeling parameters.

The modeling control unit 120 models the three-dimensional model for each layer based on the input three-dimensional model data. Here, the data of the three-dimensional model includes image data for each layer when the three-dimensional model is sliced at predetermined intervals, and the image data for each layer is referred to as modeling data D. The modeling control unit 120 ejects the molten filament FM from the ejection nozzle 18 at the target position based on the modeling data D while moving the ejection module 10 in the XY plane. By ejecting the filament FM along the tool path, one layer of modeling is performed. More specifically, the modeling control unit 120 includes a head drive control unit 122 and a discharge amount control unit 124.

The head drive control unit 122 drives the drive motors 32 and 33 based on the set value of the moving speed of the head in the XY plane set as the modeling parameter, thereby driving the XY plane of the head on which the discharge module 10 is mounted. Move the relative position within to the target position. As described above, the detection results from the X-axis and Y-axis coordinate detection mechanisms are used to control the drive of the drive motors 32 and 33. The discharge amount control unit 124 controls the discharge amount of the modeling material from the discharge nozzle 18 based on the set value of the discharge amount of the modeling material set as the modeling parameter.

The heating control unit 110 controls reheating by the heating module 20 of the lower layer Ln-1 under the upper layer Ln during modeling for each layer based on the set value of the heating amount set as the modeling parameter. By irradiating the laser light from the laser light source 21 of the heating module 20 with a predetermined output value, the lower layer is reheated within a predetermined temperature range.

The discharge module 10 is mounted on the head and moves in the XY plane based on the modeling data D, but the heating module 20 is also typically mounted on the head having the discharge module 10. Then, as described with reference to FIG. 5, the laser light source 21 is placed in a predetermined position immediately before the filament FM in the lower layer is ejected by the rotary stage RS prior to the ejection position by the ejection nozzle 18 of the ejection module 10. Is configured to be heated by irradiating it with a laser beam. Further, at the time of reheating, an appropriate reheating range as shown in FIG. 10 or 11 is set, and based on the detection result from the coordinate detection mechanism, the laser light source 21 is used only in the region set as the reheating range. It is configured so that the irradiation of the laser beam of the above is performed. The reheating range is based on the modeling data of the uppermost layer (lower layer Ln-1) for which modeling is completed and the modeling data of the lowest layer (upper layer Ln) among the layers for which modeling is not completed. A region in which the upper layer Ln is formed in the lower layer Ln-1 is determined not including the outer peripheral portion or including the outer peripheral portion.

The temperature sensor 104 is a temperature detecting means for measuring the temperature of the modeling material at the portion to be reheated in the lower layer Ln-1. In the embodiment described, the temperature sensor 104 measures the surface temperature of the lower layer during reheating or immediately after reheating (before the filament FM is discharged onto the filament FM). The temperature sensor 104 is typically mounted on a head having a heating module 20 and follows the movement of the head to detect the surface temperature of the lower layer Ln-1 heated by the heating module 20. In another embodiment, the temperature sensor 104 may be fixed to the main body of the apparatus and movably controlled according to the movement of the head on which the heating module is mounted.

The modeling parameter changing unit 130 changes the modeling parameter as necessary according to the measured value of the temperature sensor 104 during the remelting and modeling operation. More specifically, when the measured value of the temperature sensor 104 is within a predetermined temperature range, the modeling parameter changing unit 130 continues modeling without changing the modeling parameter. On the other hand, the modeling parameter changing unit 130 changes the modeling parameter when the measured value of the temperature sensor 104 deviates from the predetermined temperature range. The modeling parameters to be changed include the moving speed of the head in the XY plane, the discharge amount of the modeling material, and the heating amount. In addition to the above, the build plate temperature and the like may be further changed as modeling parameters. Depending on the detection temperature, one or more modeling parameters to be changed are selected. Preferably, at least the moving speed of the head is optimized according to the measured value of the temperature sensor 104.

Here, the predetermined temperature range is set from the temperature at which the modeling material melts to the temperature at which the modeling material is carbonized.

FIG. 13 is a schematic diagram illustrating preferable temperature conditions for reheating. As shown in FIG. 13, the filament molding material generally has a melting temperature as a characteristic peculiar to the material, and further has a carbonization temperature at a place higher than that.

When the laser device is used as the heating means, if the moving speed is the same, the temperature of the material tends to rise as the output of the laser is stronger and the heating amount is larger. Even if the amount of heating is the same, if the heating is continued, the temperature of the material rises with the passage of time. That is, since the net time for irradiating the heated portion with the laser differs depending on the moving speed of the head, the way the temperature rises changes according to the moving speed. If the temperature continues to rise due to continuous laser irradiation, the carbonization temperature of the modeling material will be reached, making it difficult to continue high-quality modeling. On the other hand, if the melting temperature is sufficiently higher, it can be said that there is room for increasing the moving speed.

The preferred temperature conditions for reheating are as shown by the red arrows in FIG. Normally, the material temperature discharged from the discharge nozzle 18 is set between the melting temperature and the carbonization temperature. If the lower layer modeling material can be melted by reheating, the lower layer material and the discharged material can be mixed and the adhesiveness can be improved. On the other hand, as described above, since the material has a carbonization temperature, it is preferable that the heating is controlled so that the temperature of the modeling material by heating is equal to or higher than the melting temperature and lower than the carbonization temperature peculiar to the modeling material. ..

The temperature due to reheating does not necessarily have to be equal to or higher than the melting temperature, as shown by the red arrow in FIG. 13 including the region below the melting temperature. Since the temperature of the discharged molding material is usually set higher than the melting temperature, even if the temperature of the reheated lower layer is lower than the temperature of the molten material, the lower layer is brought into contact with the molten filament FM. The temperature may rise to the extent that it can be sufficiently remelted. That is, the reheating may be controlled so that at least the temperature of the region of the lower layer in contact with the melted modeling material becomes equal to or higher than the temperature at which the modeling material melts. Since the temperature of the molten material to be discharged is set lower than the temperature at which carbonization is carried out, there is no concern that the temperature will rise above the temperature at which the lower layer is carbonized even when the molten material is discharged to the heated lower layer.

When the filament material is a material such as crystalline plastic in which a clear melting point can be observed, the above-mentioned melting temperature coincides with the melting point. However, some materials, such as amorphous plastics, do not have a clear melting point, and in the case of such materials, the temperature is such that a predetermined fluidity that can be mixed with the discharged filament can be obtained. Often, the above-mentioned "melting temperature" includes such a temperature depending on the molding material used. In addition, although the resin turns black due to thermal decomposition, it may change color due to oxidation even before the decomposition start temperature. Therefore, the above-mentioned "carbonization temperature" is a temperature at which unacceptable discoloration or changes in physical properties may occur in terms of quality. Can be defined.

FIG. 14 is a schematic diagram illustrating a method for adjusting the output (heating amount) of the laser light source 21 when the laser device is used as the heating means. In a particular embodiment in which the modeling material layer is heated by light energy using a laser device, the heating control unit 110 either or both of the drive time of the laser light source 21 per unit time and the drive current of the laser light source 21. The amount of heating by the laser light source 21 can be controlled by changing the above.

In the drive time control that controls the drive time per unit time, as shown schematically in Chart 300, by controlling the light emission timing T _ON and the extinguishing timing T _OFF of the laser, the laser light is applied to the lower layer per unit time. The ratio of the net time of irradiation (T _ON / T; T = T _ON + T _OFF ) is adjusted. Increasing the ratio of irradiation time per unit time (duty ratio) increases the amount of heating. Such drive time control is generally called PWM (Pulse Width Modulation). In the drive time control, even if the drive current for driving the laser is the same, the heating amount can be controlled by changing the irradiation time per unit time.

In the drive current control for controlling the drive current of the laser light source 21, the amount of laser light is adjusted by adjusting the current value for driving the laser, as schematically shown in the chart 302. Increasing the drive current increases the amount of heating. In the drive current control, even if the duty ratio is the same, the heating amount can be controlled by controlling the drive current, but the drive current control and the drive time control may be used in combination.

The three-dimensional modeling apparatus 1 according to the embodiment described will measure the temperature of the lower layer surface when the lower layer surface is remelted by heating, and will include the above-mentioned head moving speed, heating amount, and ejection amount according to the measured temperature. By changing the parameters, it is possible to shorten the molding time while increasing the adhesive strength with the molding material layer that is discharged and laminated.

<< Processing and operation >>
Subsequently, the processing and operation of the three-dimensional modeling apparatus 1 in one embodiment will be described. FIG. 15 is a flow chart showing a modeling process according to an embodiment.

The control unit 100 of the three-dimensional modeling apparatus 1 accepts the input of the data of the three-dimensional model. The 3D model data is constructed from image data for each layer when the 3D model is sliced at predetermined intervals.

The control unit 100 of the three-dimensional modeling apparatus 1 drives the X-axis drive motor 32 or the Y-axis drive motor 33 to move the discharge module 10 in the X-axis or Y-axis direction. While the discharge module 10 is moving, the control unit 100 is in a molten state or a semi-melted state from the discharge nozzle 18 to the modeling table 3 based on the image data of the lowermost layer among the input three-dimensional model data. The filament FM is discharged. As a result, the three-dimensional modeling apparatus 1 forms a layer having a shape based on the image data on the modeling table 3 (step S11).

While the ejection module 10 is moving, the control unit 100 receives the input stereo model data from the laser light source 21 based on the image data of the lowest layer among the layers for which modeling has not been completed. Irradiate the laser. As a result, the laser irradiation position in the lower layer is remelted (step S12). The control unit 100 irradiates the inside of the range indicated by the image data with a laser as in the modeling method of FIG. 7 (C), FIG. 8 (A), (C), and FIG. 9 (C). You may. Alternatively, the control unit 100 may irradiate the laser beyond the range indicated by the image data, as in the modeling method of FIGS. 7A, 7B, and 9B, for example. The heating temperature of the lower layer in step S12 is controlled to be equal to or higher than the melting temperature of the filament.

While the ejection module 10 is moving, the control unit 100 receives the input solid model data from the ejection nozzle 18 based on the image data of the lowest layer among the layers for which modeling has not been completed. The filament FM is discharged to the lower layer on the modeling table 3. As a result, a layer having a shape corresponding to the image data is formed on the lower layer (step S13). At this time, since the lower layer is remelted, the adhesiveness at the interface between the layer to be modeled and the lower layer is improved.

The process of remelting the lower layer in step S12 and the process of forming the layer in step S13 may overlap. In this case, the three-dimensional modeling apparatus 1 starts discharging the filament FM after starting the process of irradiating the lower layer with the laser and before the irradiation of the laser to the entire irradiation range is completed.

The control unit 100 of the three-dimensional modeling apparatus 1 determines whether the layer formed in step S13 is the outermost layer (step S14). The outermost layer is a layer formed based on the image data having the largest coordinate in the stacking direction (Z axis) among the data of the three-dimensional model. If NO is determined in step S14, the control unit 100 of the three-dimensional modeling apparatus 1 performs a remelting process (step S12) and a layer forming process (step S13) until the outermost layer is formed. repeat.

When the formation of the outermost layer is completed (YES in step S14), the three-dimensional modeling apparatus 1 ends the modeling process.

<< Details of modeling parameter control based on measured values of temperature sensor >>
FIG. 16 is a flow chart showing the lower layer remelting and the upper layer modeling process according to the embodiment. The process shown in FIG. 16 overlaps the process of remelting the lower layer in step S12 shown in FIG. 15 and the process of forming the upper layer on the lower layer to be remelted in step S13, and the portion of the lower layer. Corresponds to the case where the filament FM is ejected to the portion of the lower layer to form the upper layer while irradiating the laser beam.

In step S21, the control unit 100 moves the head (which has the discharge module 10 and the heating module 20) to the start point of the tool path, and the parameter change unit 130 moves the head in the XY plane and discharges the modeling material. Set the initial value of each set value of the amount and the output value of the laser. The initial values of the head movement speed, the amount of molding material discharged, and the output value of the laser are set to default values, set to user-specified values, or measured by the temperature sensor 104 or other temperature sensors, respectively. It is assumed that an appropriate initial value is set based on.

In step S22, the control unit 100 starts scanning along the tool path of the head, reheating by the heating module 20, and ejection of the filament by the ejection module 10. Here, it is assumed that the tool path for forming the entire upper layer to be modeled is calculated.

When the scanning, reheating and ejection operations are initiated, the lower layer formed of the modeling material is reheated and the molten modeling material is ejected to the heated lower layer. During the reheating and discharging operation, in the loop of steps S23 to S30, the parameter changing unit 130 prevents the lower layer molding material from melting and carbonizing based on the measured value of the lower layer temperature by the temperature sensor 104. The modeling parameters are optimized under the conditions.

In step S23, the modeling parameter changing unit 130 acquires the measured value of the lower layer temperature from the temperature sensor 104. In step S24, the modeling parameter changing unit 130 determines whether or not the measured value of the lower layer temperature by the temperature sensor 104 is lower than the lower limit temperature (melting temperature). If it is determined in step S24 that the lower layer temperature is lower than the lower limit temperature (YES), the process is branched to step S29.

In step S29, the modeling parameter changing unit 130 selects the heating amount as the modeling parameter to be changed, and changes the laser output value (heating amount) by the heating control unit 110 in the direction of increasing. By increasing the amount of heating, it is possible to improve the stacking strength without increasing the molding time. At this time, the laser output value (so that the temperature of the lower layer modeling material in contact with the molten modeling material is at least the temperature at which the temperature is equal to or higher than the melting temperature and lower than the temperature at which the modeling material is carbonized). The amount of heating) is preferably determined.

On the other hand, if it is determined in step S24 that the lower layer temperature by the temperature sensor 104 exceeds the lower limit temperature (NO), the process proceeds to step S25. In step S25, the modeling parameter changing unit 130 further determines whether or not the lower layer temperature by the temperature sensor 104 is sufficiently higher than the lower limit temperature (melting temperature). Whether or not it is sufficiently higher than the lower limit temperature (melting temperature) can be determined, for example, by whether or not the lower layer temperature by the temperature sensor 104 exceeds the lower limit temperature plus a predetermined temperature α.

If it is determined in step S25 that the lower layer temperature is sufficiently higher than the lower limit temperature (higher than the lower layer temperature + α) (YES), the process proceeds to step S26. In step S26, the modeling parameter changing unit 130 selects the moving speed as the modeling parameter to be changed, and changes the head moving speed in the direction of increasing the head moving speed by the head drive control unit 122. By changing the carriage movement speed and controlling the drive faster, the modeling time can be shortened. The head movement speed is changed within a range in which the lower layer temperature is predicted to be within a predetermined temperature range (so as not to be lower than the melting temperature). If the moving speed is increased, the temperature rise becomes smaller and the measured value of the lower layer temperature decreases, but from the viewpoint of energy saving, the head moving speed is such that the measured temperature does not fall below the melting temperature even if the heating amount is not changed. It is desirable to control.

In step S27, the modeling parameter changing unit 130 determines whether or not the moving speed has reached the upper limit. If it is determined in step S27 that the movement speed has reached the upper limit (YES), the process proceeds to step S28. In step S28, the modeling parameter changing unit 130 reselects the moving speed as the modeling parameter to be changed, and changes the head moving speed by the head drive control unit 122 so as to be less than a predetermined upper limit moving speed. This is because even if the lower layer temperature is within a predetermined temperature range, if the head moving speed is made too fast, the discharge amount with respect to the head unit moving amount (distance) decreases, and there is a possibility that the desired modeling cannot be obtained. As described above, even when the moving speed is increased, it is preferable to limit the head moving speed to less than the upper limit moving speed, with the moving speed at which deterioration such as thinning of the discharged molding material is not observed as the upper limit moving speed.

If it is determined in step S27 that the movement speed has not reached the upper limit (NO), the process directly proceeds to step S30. Further, if it is determined in step S25 that the lower layer temperature is not sufficiently higher than the lower limit temperature (the difference is less than the predetermined value α) (NO), the process directly proceeds to step S30. This is because there is little need to change the modeling parameters.

In step S30, the control unit 100 determines whether or not the end point of the tool path has been reached. If it is determined in step S30 that the end point of the tool path has not been reached, the measured value of the temperature sensor is acquired (step S23), the head movement speed is changed (steps S24 to S28), and the laser output is reached until the end point is reached. The change of the value (step S29) is repeated. When the end point of the tool path is reached (YES in step S30), in step S31, the control unit 110 ends the scanning along the tool path of the head, the reheating by the heating module 20, and the filament ejection operation by the ejection module 10. The three-dimensional modeling apparatus 1 completes the remelting process of the lower layer and the modeling process of the upper layer.

Although one embodiment of the lower layer remelting and the upper layer modeling process has been described above with reference to FIG. 16, the process shown in FIG. 16 limits the moving speed in case of a defect when the head moving speed is made too fast. Met. FIG. 17 is a flow chart showing a lower layer remelting and an upper layer modeling process according to another embodiment. Hereinafter, other cases of the lower layer remelting and the upper layer modeling process in S12 and S13 of FIG. 14 will be described with reference to FIG.

In step S41, the control unit 100 moves the head to the start point of the tool path, and the parameter change unit 130 sets the initial values of each item of the head movement speed, the amount of molding material discharged, and the output value of the laser. In step S42, the control unit 100 starts scanning, reheating, and ejection operations of the head. When the scanning, reheating and ejection operations of the head are started, the lower layer formed of the modeling material is reheated and the molten modeling material is ejected to the heated lower layer. During the reheating and discharging operation, in the loop of steps S43 to S51, the parameter changing unit 130 is used under the condition that the lower layer molding material is not melted and carbonized based on the measured value of the lower layer temperature by the temperature sensor 104. The modeling parameters are optimized.

In step S43, the modeling parameter changing unit 130 acquires the measured value of the lower layer temperature from the temperature sensor 104. In step S44, the modeling parameter changing unit 130 determines whether or not the measured value of the lower layer temperature by the temperature sensor 104 is lower than the lower limit temperature (melting temperature). If it is determined in step S44 that the lower layer temperature is lower than the lower limit temperature (YES), the process is branched to step S50.

In step S50, the modeling parameter changing unit 130 selects the heating amount as the modeling parameter to be changed, and changes the laser output value (heating amount) by the heating control unit 110 in the direction of increasing. On the other hand, if it is determined in step S44 that the lower layer temperature by the temperature sensor 104 exceeds the lower limit temperature (NO), the process proceeds to step S45. In step S45, the modeling parameter changing unit 130 determines whether or not the lower layer temperature by the temperature sensor 104 is sufficiently higher than the lower limit temperature (material melting temperature).

If it is determined in step S45 that the lower layer temperature is not sufficiently higher than the lower limit temperature (NO), the process directly proceeds to step S51. If it is determined in step S45 that the lower layer temperature is sufficiently higher than the lower limit temperature (YES), the process proceeds to step S46. In step S46, the modeling parameter changing unit 130 selects the moving speed as the modeling parameter to be changed, and changes the head moving speed by the head drive control unit 122 in a direction of increasing so that the lower layer temperature is within a predetermined temperature range. do.

In step S47, the modeling parameter changing unit 130 determines whether or not the moving speed exceeds the reference. If it is determined in step S47 that the moving speed exceeds the reference (YES), the process proceeds to step S48. In step S48, the modeling parameter changing unit 130 selects the discharge amount as the modeling parameter to be changed, and changes the discharge amount of the discharge module 10 to be larger than usual so as to compensate for the deterioration of the discharge molding material. On the other hand, if it is determined in step S47 that the moving speed does not exceed the reference (NO), the process proceeds to step S49. In step S48, the modeling parameter changing unit 130 selects the discharge amount as the modeling parameter to be changed, and keeps the discharge amount of the discharge module 10 as a normal value.

In step S51, the control unit 100 determines whether or not the end point of the tool path has been reached. If it is determined in step S51 that the end point of the tool path has not been reached, the measured value of the temperature sensor is acquired (step S43), the head movement speed is changed (steps S44 to S49), and the laser output is reached until the end point is reached. The change of the value (step S50) is repeated. When the end point of the tool path is reached (YES in step S51), in step S52, the control unit 110 ends the scanning, reheating and modeling operations, and the three-dimensional modeling apparatus 1 remelts the lower layer and the upper layer. Complete the modeling process of.

The case where the heating means is a laser device has been described above, but the heating means is not particularly limited, and as described below, in addition to the non-contact laser beam, ultrasonic waves, high-temperature warm air, and the like are used. Either a contact type heating plate or a heating tap may be used.

<<< Modification A of the embodiment >>>
Subsequently, the points different from the above-described embodiment will be described with respect to the modified example A of the embodiment. FIG. 18 is a schematic view showing the operation of lower layer heating in one embodiment.

In the modification A of the embodiment, the heating module 20 has a warm air source 21'. Examples of the warm air source 21'are a heater and a fan. In the modification A of the embodiment, the warm air source 21'heats the lower layer by blowing hot air at a high temperature and remelts it. Also in the modified example A of the embodiment, by ejecting the filament FM to the remelted lower layer to form the upper layer, the materials of the lower layer and the upper layer are mixed, and the adhesiveness between the upper layer and the lower layer is improved.

<<< Modification B of the embodiment >>>
Subsequently, the modified example B of the embodiment will be described which is different from the above-described embodiment. FIG. 19 is a schematic view showing the operation of lower layer heating in one embodiment.

In the modification B of the embodiment, the heating module 20 of the three-dimensional modeling apparatus 1 is replaced with the heating module 20'. The heating module 20' includes a heating plate 28 that heats and pressurizes the lower layer of the three-dimensional model M, a heating block 25 that heats the heating plate 28, and a cooling block 22 for preventing heat conduction from the heating block 25. To prepare for. The heating block 25 includes a heat source 26 such as a heater and a thermocouple 27 for controlling the temperature of the heating plate 28. The cooling block 22 includes a cooling source 23. A guide 24 is provided between the heating block 25 and the cooling block 22.

The heating module 20'is held so as to be slidable with respect to the X-axis drive shaft 31 (X-axis direction) extending in the left-right direction of the device (left-right direction = X-axis direction in FIG. 1) via a connecting member. .. The heating module 20'is heated by the heating block 25 to a high temperature. In order to reduce the transfer of the heat to the X-axis drive motor 32, it is preferable that the transfer path or the guide 24 including the filament guide 14 and the like has low thermal conductivity.

In the heating module 20', the lower end of the heating plate 28 is arranged so as to be one layer lower than the lower end of the discharge nozzle 18. While scanning the discharge module 10 and the heating module 20 in the direction of the white arrow shown in FIG. 19, the filament is discharged, and at the same time, the heating plate 28 reheats the layer immediately below the layer being modeled. As a result, the temperature difference between the layer being modeled and the layer below it becomes small, and the materials are mixed between the layers, so that the interlayer strength of the modeled object is improved. Examples of the method for cooling the heated layer include a method of setting the atmospheric temperature, a method of leaving the heated layer for a predetermined time, a method of using a fan, and the like.

According to the modification B of the embodiment, the adhesion of the interface between the layers can be improved by physically mixing the materials between the layers. Further, according to the modification B of the embodiment, the lower layer is selectively heated without destroying the outer shape of the modeled object, and the next ejection is performed while the lower layer is remelted, whereby the adhesion of the interface is increased. improves.

<<< Modification C of the embodiment >>>
Subsequently, the difference between the modified example C of the embodiment and the modified example B of the above-described embodiment will be described. FIG. 20 is a schematic view showing the operation of lower layer heating in one embodiment.

In the modification C of the embodiment, the heating plate 28 in the heating module 20'is replaced with the tap nozzle 28'. The tap nozzle 28'is heated by the heating block 25. The tap nozzle 28'heats and pressurizes the lower layer of the three-dimensional model M by the tap operation of repeatedly tapping the three-dimensional model M from vertically above by the power of a motor or the like. As a result, the temperature difference between the layer being modeled and the layer below it becomes small, and the materials are mixed between the layers, so that the strength between the layers of the modeled object is improved. After the tap operation, the filament FM is discharged from the discharge nozzle 18 so as to fill the surface of the lower layer recessed by the tap operation. By filling the recessed portion of the lower layer with the filament FM, the shape of the outermost surface is finished smoothly.

<<< Modification D of the embodiment >>>
Subsequently, the modification D of the embodiment will be described with respect to the differences from the above-described embodiment. FIG. 21 is a schematic view showing the operation of lower layer heating in one embodiment.

In the modification D of the embodiment, the heating module 20 is provided with a side surface cooling unit 39 for cooling the side surface of the three-dimensional model M, that is, the surface parallel to the Z axis. The side surface cooling unit 39 is not particularly limited as long as it is a cooling source capable of cooling the side surface of the three-dimensional model M, but a fan is exemplified.

If the outer peripheral portion of the three-dimensional model M is reheated without performing the process of maintaining the outer shape, the outer shape collapses and the modeling accuracy deteriorates. Therefore, in the modified example D of the embodiment, the material is obtained while maintaining the shape of the modeled portion by reheating the outer peripheral portion of the three-dimensional modeled object M while applying cooling air to the side surface of the three-dimensional modeled object M. Can be laminated.

<<< Modification E of the embodiment >>>
Subsequently, the modified example E of the embodiment will be described as different from the above-described embodiment.

When modeling is performed while heating the lower layer or the modeling space, the viscosity of the heated portion in the three-dimensional modeled object M decreases, so that the outer shape collapses and the modeling accuracy may be lost. On the other hand, if the lower layer or the modeling space is modeled without heating, the viscosity of the three-dimensional model M becomes high, but it becomes difficult to maintain the strength in the stacking direction. Therefore, in the modified example E of the embodiment, the filament is used for modeling with the material composition unevenly distributed.

FIG. 22 is a cross-sectional view showing an example of a filament in which the material composition is unevenly distributed. In the example of FIG. 22A, the highly viscous resin Rh is arranged on both sides of the filament F, and the low viscosity resin Rl is arranged in the central portion.

The highly viscous resin Rh arranged on both sides of the filament F is not particularly limited, and examples thereof include a resin made highly viscous by blending fillers such as alumina, carbon black, carbon fiber, and glass fiber. When the filler inhibits a desired function, a resin having a controlled molecular weight may be used as the highly viscous resin Rh.

The low-viscosity resin Rl arranged at the center of the filament F is not particularly limited, and examples thereof include a resin having a low molecular weight grade.

FIG. 23 is a cross-sectional view of the ejected product of the filament of FIG. 22. FIG. 24 is a cross-sectional view of a modeled object formed by using the filament of FIG. 22. By ejecting the filament of FIG. 22 (A), the ejected product having the shape of FIG. 23 (A) is obtained, and the modeled product of FIG. 24 is obtained. In the modeled object of FIG. 24, since the highly viscous resin is arranged on the outer peripheral portion, the modeled object is inevitably less likely to collapse.

FIG. 22B shows another example of a filament in which the material composition is unevenly distributed. By ejecting the filament of FIG. 22 (B), the ejected product having the shape of FIG. 23 (B) can be obtained. As described above, even if the filament of FIG. 22 (B) is used, a modeled product in which a highly viscous resin is arranged on the outer peripheral portion can be obtained. In addition, from the viewpoint of the manufacturing method, this configuration that wraps the low-viscosity resin has an advantage that it is easier to form a filament than the configuration of FIG. 23 (A).

However, when the filament of FIG. 23 (B) is used, the lower part of the layer is also in a highly viscous state. Highly viscous resins often have a higher melting point than less viscous resins. When the lower layer is remelted at a high temperature, it is preferable to avoid heating the outer peripheral portion of the modeled object in order to prevent the molten resin from moving in the horizontal direction. Therefore, as the heating means, a laser or the like capable of heating in a small spot is preferable.

In order to improve the adhesion of the outer peripheral portion in the stacking direction, when heating the outer peripheral portion, it is preferable to heat the outer peripheral portion by directly hitting a plate or the like from the side of the modeled object. This restricts the horizontal movement of the resin due to the decrease in viscosity. FIG. 25 is a schematic diagram showing an example of a three-dimensional modeling apparatus having regulatory means.

In the example of FIG. 25, the three-dimensional modeling apparatus 1 is provided with an assist mechanism 41 as an example of the regulating means. In the FFF method, the thickness of one layer is about 0.10 to 0.30 mm. Therefore, the plate in the assist mechanism 41 is a thin plate such as a thickness gauge. The assist mechanism 41 is fixed to the discharge module 10 or a bracket indirectly fixed to the discharge module 10.

The plate in the assist mechanism 41 is preferably heated to a temperature higher than normal temperature. Although it depends on the resin used, in the case of a crystalline resin, when it is hit by a plate at room temperature, it is rapidly cooled, so that amorphization progresses and the desired strength may not be obtained.

Viscosity is generally expressed as a function of temperature and shear rate. Engineering plastics, super engineering plastics, etc. used in Fused Deposition Modeling (FFF) show non-linear behavior with respect to variables such as temperature and shear rate, so even if the melting point of the resin is not Tm or higher, FFF The shear resistance required by the method, that is, the viscosity of the resin, may be obtained. On the other hand, if the viscosity at the desired shear rate (S. Rate) is too low in the region above Tm, dripping from the nozzle, insufficient drawing during filament drawing (retract operation), and the accompanying short shot at the initial stage of ejection. Problems such as collapse of the modeled object occur.

In a resin having a predetermined temperature of Tm or more, generally, S. Rate = 0, that is, the highest viscosity at the temperature is obtained during non-discharge operation. If the liquid drips even in this state, compositing the resin with a filler can be an effective means for preventing the dripping. By adding a filler to the resin and controlling the compounding ratio or the particle size / fiber length distribution of the compounded material, thixotropy during melting is imparted, it is difficult to drip during non-discharge operation, and the viscosity is low during discharge operation. Will be.

The method of adding a filler to the filament is also suitable for the collapse of the modeled object that tends to occur with an increase in the temperature of the lower layer. If the modeling accuracy cannot be maintained even by adding the filler, it is preferable to regulate the side surface of the modeled object.

<<< Modification F of the embodiment >>>
Subsequently, the modified example F of the embodiment will be described as different from the modified example E of the above embodiment.

When a filament having an unevenly distributed material structure is used, it is preferable to regulate the direction of the filament introduced into the discharge module 10 so that the highly viscous resin Rh is arranged on the outer peripheral portion of the modeled object.

FIG. 26 is a flow chart showing an example of a process for restricting the direction of the filament. The image pickup module 101 of the three-dimensional modeling apparatus 1 takes an image of the filament introduced into the ejection module 10, and transmits the obtained image data to the control unit 100.

The control unit 100 receives the image data of the filament transmitted by the image pickup module 101 (step S21). The control unit 100 analyzes the received image data of the filament and calculates the rotation amount (step S22). The method for calculating the amount of rotation is not particularly limited, and an example thereof is a method for determining the amount of rotation so that the boundary between the high-viscosity resin Rh and the low-viscosity resin Rl in the filament F is at a predetermined position. For example, when the filament is discharged while moving the discharge module 10 in the X-axis direction, the high-viscosity resin Rh in the filament is unevenly distributed in the positive and negative directions of the Y-axis, so that the outermost shell of the modeled object has high viscosity. The resin is placed. Therefore, the control unit 100 determines the amount of rotation of the filament so that the resin Rh is arranged unevenly in the positive and negative directions of the Y axis.

The control unit 100 transmits a signal for rotating the filament to the torsion rotation mechanism 102 based on the determined rotation amount. The torsional rotation mechanism 102 rotates the filament based on the signal (step S23). This regulates the filament in the desired direction.

When the highly viscous resin is arranged on the outside of the filament, the flow velocity on the wall side of the filament becomes extremely slow in the transfer path, and the highly viscous resin stays, so that the filament is discharged in a desired arrangement. There are times when it cannot be done. Therefore, in the region downstream of the heating block 25, that is, in the region where a temperature equal to or higher than the melting point is applied, it is preferable that the inner wall of the transfer path is processed with fluorine or the like having high heat resistance. By forming the release layer in the transfer path, the frictional resistance between the molten resin and the inner wall of the transfer path is reduced, and the highly viscous resin is less likely to stay.

Further, it is preferable that the control unit 100 performs feedforward control in order to prevent a delay in control in consideration of a time lag in transport in the section from the torsion rotation mechanism 102 to the discharge nozzle 18. For example, the control unit 100 controls the drive of the torsional rotation mechanism 102 so that the direction of the filament is switched at the timing when the traveling direction of the discharge module 10 bends. Further, even when the discharge module 10 is advanced in a curved line, the control unit 100 controls the drive of the torsion rotation mechanism 102 step by step in consideration of the time lag.

If the filament is extremely twisted, it may get entangled in the path from the reel 4 to the introduction portion of the discharge module 10. Untangling this entanglement is very cumbersome for the user. Therefore, it is preferable that a guide tube is introduced from the reel 4 to the introduction portion. However, if the filament is extremely twisted, the frictional resistance between the guide tube and the filament increases, and the filament may not be introduced normally. In addition, the filament may be scraped at an orifice having a narrow inner diameter such as a joint of a guide tube. Further, in the reinforced filament or the like containing a filler, the flexibility peculiar to the resin is often lost. When a torsional load is applied to such a filament, the filament may break and normal modeling may not be possible.

Therefore, it is preferable that the control unit 100 regulates the cumulative twist amount of the filament to, for example, ± 180 ° from the reference angle.

Further, for example, as shown in FIG. 23, a mechanism capable of rotating the entire discharge module 10 may be used instead of the mechanism for rotating the filament so that the resin is arranged in a desired state in the discharged material. In this case, the thermocouple 17 that controls the heat source 16, the wiring of the heat source 16 itself, the wiring of the cooling source 13, and a plurality of wiring systems such as the overheat protector also rotate at the same time. However, it becomes complicated from the viewpoint of wiring.

<<< Modification G of the embodiment >>>
Subsequently, the modified example G of the embodiment will be described with respect to the differences from the above-described embodiment. FIG. 27 is a schematic diagram showing a modeling and surface treatment operation in one embodiment.

In the modification G of the embodiment, the three-dimensional modeling apparatus 1 includes a heating module 20 ″. The heating module 20 ″ has a horn 30 that heats and pressurizes the three-dimensional model M. The three-dimensional modeling device 1 is provided with an ultrasonic vibration device. The horn 30 is moved from above to below the laminated surface of the three-dimensional model M by a Z-axis drive motor, and applies pressure to the laminated surface. As a result, the ultrasonic vibration generated by the ultrasonic vibration device is transmitted to the three-dimensional model M. When the vibration of ultrasonic waves is transmitted to the three-dimensional model M, the upper layer Ln and the lower layer Ln-1 in the three-dimensional model M are welded and joined. In the three-dimensional modeling apparatus 1, the number of horns 30 is not limited to one, and is appropriately selected. When a plurality of horns 30 are provided, the shapes of the horns may not be unified, and horns having different shapes may be mounted.

<< Main effects of the embodiment >>
The discharge module 10 (an example of a discharge means) of the three-dimensional modeling device 1 (an example of a modeling device) of the above embodiment discharges a molten filament (an example of a modeling material) to form a modeling material layer. The heating module 20 (an example of the heating means) of the three-dimensional modeling apparatus 1 heats the formed modeling material layer. The discharge module 10 is formed by laminating the modeling material layer on the heated modeling material layer by discharging the molten filament. According to the above embodiment, by remelting and ejecting filaments to the modeling material layer (lower layer) and laminating the modeling material layer (upper layer), the materials in the layers are mixed, so that the strength in the stacking direction in the modeled object is improved. Can be made to. In addition, by laminating the upper layers, it is possible to form the model without affecting the visibility of the outer shape.

The heating module 20 of the three-dimensional modeling apparatus 1 selectively heats a predetermined area of the modeling material layer. This makes it possible to model while maintaining the shape of the modeled object.

In particular, by removing the peripheral portion of the shape from the reheating range, the occurrence of external disturbance is prevented.

Further, according to the above-described embodiment, the conditions under which the lower layer modeling material is not melted and carbonized based on the measured value of the lower layer temperature detected by the temperature sensor 104 during the reheating of the lower layer and the modeling operation of the upper layer. The modeling parameters are optimized at. Therefore, by remelting the material layer by the heating means, it is possible to increase the strength in the stacking direction and shorten the modeling time by optimizing the modeling parameters.

Further, in a specific embodiment, a variable range of the head moving speed is set, and if necessary, the discharge amount of the discharge module is changed according to the changed head moving speed, so that the modeled object by changing the head moving speed is used. Quality deterioration can be prevented.

The rotary stage RS (an example of transport means) of the three-dimensional modeling apparatus 1 transports the heating module 20 so that it can be heated from different directions with respect to a predetermined position. As a result, the heating module 20 can heat the modeling material layer following the movement of the discharge module 10.

The three-dimensional modeling apparatus 1 includes a temperature sensor 104 (an example of measuring means) for measuring the temperature of the modeling material layer heated by the heating module 20. The heating module 20 heats the modeling material layer based on the temperature measured by the temperature sensor 104. Thereby, the three-dimensional modeling apparatus 1 can appropriately reheat the modeling material layer according to desired characteristics such as the adhesive strength between the layers and the modeling accuracy.

The heating module 20 may be a laser light source 21 (an example of a source irradiation device) that irradiates a laser beam. As a result, the heating module 20 can selectively heat the modeled object without coming into contact with the modeled object.

The heating module 20 may be a warm air source (an example of the blowing means) for blowing the heated air. As a result, the heating module 20 can selectively heat the modeled object without coming into contact with the modeled object.

The heating module 20'may be a heating plate 28 or a tap nozzle 28'(an example of a member) that contacts and heats the modeling material layer. Thereby, the heating module 20'can selectively heat the modeled object.

The three-dimensional modeling apparatus 1 may include a plurality of heating modules 20. As a result, even if the scanning direction of the discharge module 10 changes, the modeled object can be heated by any of the heating modules 20, so that the modeling time is shortened.

The side cooling unit 39 (an example of the cooling means) of the three-dimensional modeling apparatus 1 cools the outer peripheral portion of the modeled object formed of the modeling material. As a result, the three-dimensional modeling device 1 can perform modeling while maintaining the shape of the modeled object.

A plurality of materials having different viscosities are arranged on the filament. As a result, the discharge module 10 can discharge the filament so that the material having a lower viscosity is arranged on the outer peripheral portion based on the control by the control unit 100.

The assist mechanism 41 (an example of a support member) of the three-dimensional modeling apparatus 1 supports the formed modeling material layer. This makes it possible to perform modeling while maintaining the shape of the formed modeling material layer.

1 Three-dimensional modeling device 3 Modeling table 10 Discharge module 18 Discharge nozzle 20, 20', 20'" Heating module 21 Laser light source 28 Heating plate 28'Tap nozzle 37 Cleaning brush 38 Dust box 39 Side cooling unit 41 Assist mechanism 100 Control unit 110 Heating control unit 120 Modeling control unit 122 Head drive control unit 124 Discharge amount control unit 130 Modeling parameter change unit RS Rotation stage

Japanese Unexamined Patent Publication No. 2005-335380

Claims (12)

A heating means for heating the first modeling material layer formed of the modeling material, and
A temperature detecting means for detecting the temperature of the first modeling material layer, and
A discharge means for discharging the melted modeling material to the heated first modeling material layer and laminating the second modeling material layer.
A modeling apparatus having a changing means for changing a modeling parameter including an in-plane movement speed of the discharging means based on the temperature detected by the temperature detecting means when modeling the second modeling material layer. The modeling apparatus according to claim 1 , wherein the changing means changes the moving speed of the discharging means in the plane so that the temperature detected by the temperature detecting means falls within a predetermined temperature range. The predetermined temperature range has a lower limit of a temperature such that the temperature of the modeling material of the first modeling material layer in contact with the molten modeling material is equal to or higher than the temperature at which the modeling material melts, and the modeling material The modeling apparatus according to claim 2 , wherein the temperature range is up to the temperature at which the material is carbonized. The modeling apparatus according to any one of claims 1 to 3 , wherein the changing means limits the moving speed of the discharging means in the plane to less than a predetermined upper limit moving speed. The modeling device according to any one of claims 1 to 4 , wherein the modeling parameter further includes a discharge amount of the discharge means, and the discharge amount of the discharge means is changed according to the moving speed. .. The modeling device according to claim 5 , wherein the changing means changes the discharging amount when the moving speed in the plane of the discharging means exceeds a predetermined threshold moving speed. The modeling apparatus according to any one of claims 1 to 6 , wherein the changing means changes the heating amount by the heating means when the temperature detected by the temperature detecting means is lower than a predetermined lower limit. The modeling apparatus according to any one of claims 1 to 7, wherein the temperature detecting means detects the temperature of the surface of the first modeling material layer. The temperature detecting means includes a portion heated by the heating means on the surface of the first modeling material layer, following the movement of the portion heated by the heating means accompanying the movement of the discharging means. The modeling apparatus according to any one of claims 1 to 8 , which is configured to detect the temperature of the region. The modeling device according to claim 9 , wherein the heating means is an irradiation device that irradiates a laser beam. It is a modeling method performed by a modeling device.
The step of preparing the first modeling material layer formed of the modeling material,
The step of heating the first modeling material layer and
The step of detecting the temperature of the first modeling material layer and
The step of ejecting the melted modeling material to the first modeling material layer heated in the heating step and laminating the second modeling material layer is included, and the laminating step includes the step of laminating the second modeling material layer. A modeling method comprising the step of changing the modeling parameters including the in-plane movement speed of the ejection means in the stacking step based on the temperature detected in the detecting step. A heating means for heating the first modeling material layer formed of the modeling material, and
A temperature detecting means for detecting the temperature of the first modeling material layer, and
A discharge means for discharging the melted modeling material to the heated first modeling material layer and laminating the second modeling material layer.
A modeling system comprising a changing means for changing modeling parameters including the in-plane movement speed of the discharging means based on the temperature detected by the temperature detecting means in modeling the second modeling material layer.

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