JP2016135579A - Three-dimensional object molding device, production method of three-dimensional object, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for preventing a phenomenon in which powder body density unevenness occurs, when a next powder body layer is formed, because a part of a molding layer formed on a powder body layer becomes a recess state, relative to height of an area other than the molding layer.SOLUTION: A three-dimensional molding method comprises: forming a molding layer 30 by discharging a droplet of a molding liquid from a head, while moving a discharge unit according to molding data of a first layer; detecting height of a surface of the molding layer 30, and height of a surface of an area on which, the molding layer 30 is not formed, out of a powder body layer 31, by a height sensor 561; calculating a difference Δt between both heights, and storing; raising a molding stage 24 by the stored and held difference Δt; removing a surplus powder body 20 of a height part of the difference Δt by a flatness roller 12; and performing an operation for making heights of the surface of the molding layer 30, and the surface of the area where the molding layer 30 is not formed on the powder body layer 31, uniform.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a three-dimensional modeling apparatus, a three-dimensional model production method, and a program.

  As a three-dimensional modeling apparatus (three-dimensional modeling apparatus) for modeling a three-dimensional modeled object (three-dimensional modeled object), for example, one that models by a layered modeling method is known. This is because, for example, a flat metal or non-metal powder layer is formed on a modeling stage, a modeling liquid is discharged from the head onto the powder layer, and a thin modeling layer in which the powder is bonded , Forming a powder layer on this modeling layer and repeating the process of forming the modeling layer again to form a three-dimensional model by laminating the modeling layers.

  Conventionally, pre-planarization is performed by setting a thickness determination distance, which is a distance between a flat surface on which the bottom surface of the powder layer to be formed, and the planarization roller are larger than the thickness of the powder layer, Thereafter, there is known a method in which the final flattening is performed by matching the thickness determination distance with the thickness of the powder layer to form the powder layer (Patent Document 1).

JP 2014-065179 A

  As described above, when the modeling liquid is landed on the powder layer to form the modeling layer, the surface of the modeling layer (modeling portion) formed by landing of the modeling liquid includes the modeling layer. It becomes a state dented with respect to the surface (surface of the area | region of the unshaped part in which the modeling layer is not formed).

  Therefore, when the next powder layer is formed, the thickness of the powder layer supplied differs between the region where the modeling layer is formed and the region where the modeling layer is not formed, resulting in density unevenness in the resulting modeled object. There are challenges.

  This invention is made | formed in view of said subject, and aims at improving the quality of a molded article.

In order to solve the above problems, the three-dimensional modeling apparatus according to the present invention is:
In the three-dimensional modeling apparatus for forming a three-dimensional model by sequentially laminating a modeling layer in which the powder of the powder layer is bonded to the powder layer by discharging droplets of the modeling liquid,
When forming the next powder layer on the powder layer on which the modeling layer is formed, before forming the next layer, the surface of the modeling layer and the powder on which the modeling layer is formed It was set as the structure provided with the means to perform the operation | movement which arranges the height with the surface of the area | region where the said modeling layer of the layer is not formed.

  According to the present invention, the quality of a model can be improved.

It is principal part perspective explanatory drawing of the 1st example of the three-dimensional model | molding apparatus which concerns on this invention. It is a schematic side surface explanatory drawing similarly. It is a section explanatory view of a modeling part. It is a perspective explanatory view of a modeling part. It is a block diagram of a control part. It is typical sectional explanatory drawing of the modeling part with which it uses for description of the flow of modeling. It is a flowchart with which it uses for description of control of modeling operation | movement by the control part in this embodiment. It is explanatory drawing with which it uses for description of the modeling operation. FIG. 9 is an explanatory diagram for explaining an operation following FIG. 8. FIG. 10 is an explanatory diagram for explaining an operation following FIG. 9. FIG. 11 is an explanatory diagram for explaining an operation following FIG. 10. FIG. 12 is an explanatory diagram for explaining an operation following FIG. 11. FIG. 13 is an explanatory diagram for explaining an operation following FIG. 12. It is principal part perspective explanatory drawing of the 2nd example of a three-dimensional modeling apparatus. It is sectional explanatory drawing of the modeling part similarly demonstrated with the flow of modeling.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. An example of the three-dimensional modeling apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is an explanatory perspective view of a main part of the three-dimensional modeling apparatus, FIG. 2 is an explanatory schematic side view, FIG. 3 is an explanatory sectional view of a modeling unit, and FIG. FIG. 3 shows a state during modeling.

  This three-dimensional modeling apparatus is a powder modeling apparatus (also referred to as a powder modeling apparatus), and a modeling part 1 in which a modeling layer 30 to which powder (powder) is bonded is formed, and a modeling liquid 10 is applied to the modeling part 1. And a modeling unit 5 for discharging and modeling a three-dimensional model.

  The modeling unit 1 includes a powder tank 11, a flattening roller (also referred to as a recoater roller) 12 that is a rotating body as a flattening unit, and the like.

  The powder tank 11 has a supply tank 21 for supplying the powder 20 and a modeling tank 22 in which a modeled object is modeled. The bottom of the supply tank 21 can be raised and lowered in the vertical direction (height direction) as a supply stage 23. Similarly, the bottom of the modeling tank 22 can be moved up and down in the vertical direction (height direction) as the modeling stage 24. A three-dimensional model is modeled on the modeling stage 24.

  The supply stage 23 is raised and lowered by a motor 27, and the modeling stage 24 is raised and lowered by a motor 28.

  The flattening roller 12 supplies the powder 20 supplied on the supply stage 23 of the supply tank 21 to the modeling tank 22, and flattens it by the flattening roller 12 which is a flattening means, thereby forming a powder layer 31 to be described later. Form.

  The flattening roller 12 can be reciprocated relative to the stage surface in the arrow Y direction, which is a direction along the stage surface of the modeling stage 24 (surface on which the powder 20 is loaded), by the reciprocating mechanism 25. And is rotationally driven by the motor 26.

  As illustrated in FIG. 3, the modeling unit 5 includes a discharge unit 51 having one or more liquid discharge heads (hereinafter referred to as “heads”) 50 that discharge the modeling liquid 10 onto the powder layer 31 on the modeling stage 24. It has.

  The discharge unit 51 includes a head for discharging a cyan modeling liquid, a head for discharging a magenta modeling liquid, a head for discharging a yellow modeling liquid, a head for discharging a black modeling liquid, and a head for discharging a clear modeling liquid. A plurality of tanks containing each of these cyan modeling liquid, magenta modeling liquid, yellow modeling liquid, black modeling liquid, and clear modeling liquid are mounted on the tank mounting portion 56.

  The modeling unit 5 also includes a head cleaning mechanism (cleaning device 555 in FIG. 5) that cleans the head 50 of the discharge unit 51.

  The head cleaning mechanism (device) is mainly composed of a cap and a wiper. The cap is brought into close contact with the nozzle surface below the head, and the modeling liquid is sucked from the nozzle. This is for discharging the powder clogged in the nozzle and discharging the modeling liquid having a high viscosity. Thereafter, the nozzle surface is wiped (wiped) for forming a meniscus of the nozzle (the inside of the nozzle is in a negative pressure state). Further, the head cleaning mechanism covers the nozzle surface of the head when the modeling liquid is not discharged, and prevents powder from being mixed into the nozzle and drying of the modeling liquid.

  As shown in FIG. 2, the modeling unit 5 includes a slider portion 53 that is movably held by a guide member 52, and the entire modeling unit 5 can reciprocate in the arrow Y direction (sub-scanning direction). The modeling unit 5 is reciprocally moved in the arrow Y direction by a scanning mechanism including a motor 552 described later.

  The discharge unit 51 is supported by guide members 54 and 55 so as to be reciprocally movable in the arrow X direction (main scanning direction), and is reciprocated in the X direction by a scanning mechanism including a motor 550 described later.

  The discharge unit 51 is supported so as to be movable up and down in the arrow Z direction together with the guide members 54 and 55, and is moved up and down in the Z direction by a lifting mechanism including a motor 551 described later.

  Here, the detail of the modeling part 1 is demonstrated with reference to FIG.3 and FIG.4 mentioned above.

  The powder tank 11 has a box shape and includes a tank in which two upper surfaces of a supply tank 21 and a modeling tank 22 are opened. A supply stage 23 is arranged inside the supply tank 21 and a modeling stage 24 is arranged inside the modeling tank 22 so as to be movable up and down.

  The side surface of the supply stage 23 is disposed in contact with the inner side surface of the supply tank 21. The side surface of the modeling stage 24 is disposed so as to contact the inner surface of the modeling tank 22. The upper surfaces of the supply stage 23 and the modeling stage 24 are kept horizontal.

  As shown in FIG. 4, a powder dropping port 29 having a concave shape with an open upper surface is provided around the powder tank 11 (not shown in FIG. 3). Excess powder 20 accumulated by the flattening roller 12 when the powder layer is formed falls on the powder dropping port 29. The surplus powder 20 that has fallen into the powder drop opening 29 is returned to the powder supply unit that supplies the powder to the supply tank 21.

  A powder supply device (powder supply means, powder supply device 554 in FIG. 5) (not shown in FIG. 1) has a tank shape and is disposed above the supply tank 21. The powder in the tank is supplied to the supply tank 21 during the initial operation of modeling or when the amount of powder in the supply tank 21 decreases. Examples of the powder conveying method for supplying powder include a screw conveyor method using a screw and an air transportation method using air.

  The flattening roller 12 has a function of transferring and supplying the powder 20 from the supply tank 21 to the modeling tank 22 to form a powder layer 31 having a predetermined thickness.

  The flattening roller 12 is a rod-shaped member that is longer than the inner dimensions of the modeling tank 22 and the supply tank 21 (that is, the width of the portion where powder is supplied or charged), and the reciprocating mechanism 25 described above. Is reciprocated in the direction along the stage surface (in the direction of arrow Y parallel to the stage surface).

  The flattening roller 12 moves horizontally from the outside of the supply tank 21 so as to pass over the supply tank 21 and the modeling tank 22 while being rotated by the motor 26, whereby the powder 20 moves onto the modeling tank 22. And transported.

  Further, as shown in FIG. 3, a powder removing plate 13 that is a powder removing member for removing the powder 20 attached to the flattening roller 12 is disposed in contact with the peripheral surface of the flattening roller 12. ing.

  The powder removing plate 13 moves together with the flattening roller 12 while in contact with the peripheral surface of the flattening roller 12. Further, the powder removing plate 13 is arranged in a counter direction when the flattening roller 12 rotates in the rotation direction when flattening.

  In the present embodiment, the powder tank 11 of the modeling unit 1 has two tanks, a supply tank 21 and a modeling tank 22, but only the modeling tank 22 is used to supply powder from the powder supply device to the modeling tank 22. It is also possible to adopt a configuration in which the material is supplied and flattened by a flattening means.

  Next, the outline | summary of the control part of the said three-dimensional modeling apparatus is demonstrated with reference to FIG. FIG. 5 is a block diagram of the control unit.

  The control unit 500 includes a CPU 501 that controls the entire three-dimensional modeling apparatus, a program that includes a program according to the present invention for causing the CPU 501 to execute processing according to the present invention, a ROM 502 that stores other fixed data, and image data A main control unit 500A including a RAM 503 for temporarily storing (print data) and the like is provided.

  The control unit 500 includes a non-volatile memory (NVRAM) 504 for holding data even when the apparatus is powered off. Further, the control unit 500 includes an ASIC 505 that processes image processing for performing various signal processing on image data and other input / output signals for controlling the entire apparatus.

  The control unit 500 includes an I / F 506 for transmitting and receiving data and signals used when receiving modeling data from the external modeling data creating apparatus 600. The modeling data creation device 600 is a device that creates modeling data obtained by slicing a final shaped model into each modeling layer, and is configured by an information processing device such as a personal computer.

  The control unit 500 includes an I / O 507 for taking in detection signals of various sensors.

  The control unit 500 includes a head drive control unit 508 that drives and controls each head 50 of the discharge unit 51.

  The control unit 500 includes a motor driving unit 510 that drives an X-direction scanning motor 550 that moves the discharge unit 51 in the arrow X direction, and a motor driving unit that drives a Y-direction scanning motor 552 that moves the modeling unit 5 in the arrow Y direction. 512.

  The control unit 500 includes a motor drive unit 511 that drives a Z-direction lift motor 551 that moves (lifts) the discharge unit 51 in the arrow Z direction. In addition, raising / lowering to the arrow Z direction can also be set as the structure which raises / lowers the modeling unit 5 whole.

  The control unit 500 includes a motor drive unit 513 that drives a motor 27 that raises and lowers the supply stage 23, and a motor drive unit 514 that drives a motor 28 that raises and lowers the modeling stage 24.

  The control unit 500 includes a motor drive unit 515 that drives the motor 553 of the reciprocating mechanism 25 that moves the flattening roller 12, and 516 that drives the motor 26 that rotationally drives the flattening roller 12.

  The control unit 500 performs a cleaning drive that drives a supply system drive unit 517 that drives the powder supply device 554 that supplies the powder 20 to the supply tank 21 and a cleaning device 555 that cleans (maintains and maintains) the discharge unit 51. Part 518.

  The I / O 507 of the control unit 500 includes detection signals such as a height sensor 561 for detecting the surface height of the powder layer 31 and the modeling layer 30, and a temperature / humidity sensor 560 for detecting temperature and humidity as environmental conditions. Detection signals from other sensors are input.

  An operation panel 522 for inputting and displaying information necessary for this apparatus is connected to the control unit 500.

  The modeling apparatus is configured by the modeling data creating apparatus 600 and the three-dimensional modeling apparatus (powder additive modeling apparatus) 601.

  Next, a general flow of modeling will be described with reference to FIG. FIG. 6 is a schematic cross-sectional explanatory view of a modeling part for explaining the modeling flow.

  A first modeling layer 30 is formed on the modeling stage 24 of the modeling tank 22.

  When the next modeling layer 30 is formed on the modeling layer 30, as shown in FIG. 6A, the supply stage 23 of the supply tank 21 is raised in the arrow Z1 direction, and the modeling stage 24 of the modeling tank 22 is moved to the arrow. Lower in the Z2 direction.

  At this time, the descending distance of the modeling stage 24 is set so that the distance between the powder layer surface of the modeling tank 22 and the lower portion (downward tangent portion) of the flattening roller 12 is Δt1. This interval Δt1 corresponds to the thickness of the powder layer 31 to be formed next. The interval Δt1 is preferably about several tens to 100 μm.

  Next, as shown in FIG. 6B, the powder 20 positioned above the upper surface level of the supply tank 21 is rotated in the Y2 direction (modeling tank 22) while rotating the flattening roller 12 in the forward direction (arrow direction). The powder 20 is transferred and supplied to the modeling tank 22 (powder supply).

  Further, as shown in FIG. 6C, the flattening roller 12 is moved in parallel with the stage surface of the modeling stage 24 of the modeling tank 22, and as shown in FIG. 6D, the modeling layer 30 of the modeling stage 24 is obtained. A powder layer 31 having a predetermined thickness Δt1 is formed (flattening). After the powder layer 31 is formed, the flattening roller 12 is moved in the arrow Y1 direction and returned to the initial position.

  Here, the flattening roller 12 can move while maintaining a constant distance from the upper surface level of the modeling tank 22 and the supply tank 21. Since the powder 20 is transported onto the modeling tank 22 by the flattening roller 12 while being kept constant, the powder having a uniform thickness Δt1 is formed on the modeling tank 22 or on the already formed modeling layer 30. Layer 31 can be formed.

  Thereafter, as shown in FIG. 6E, the droplet of the modeling liquid 10 is discharged from the head 50 of the discharge unit 51 to form the next modeling layer 30 in a stacked manner (modeling).

  The modeling layer 30 is formed by, for example, mixing the modeling liquid 10 discharged from the head 50 with the powder 20 so that the adhesive contained in the powder 20 is dissolved and the dissolved adhesives are bonded to each other. It is formed by combining the powder 20.

  Next, a new modeling layer is formed by repeating the above-described powder supply / planarization process and modeling liquid discharging process by the head. At this time, the new modeling layer and the lower modeling layer are integrated to form a part of the three-dimensional modeled object.

  Thereafter, a three-dimensional shaped object (three-dimensional object) is completed by repeating the powder supply / flattening process and the modeling liquid discharging process by the head as many times as necessary.

  Next, an example of the three-dimensional modeling powder material (powder) and the modeling liquid used in the three-dimensional modeling apparatus will be described. In addition, it is not limited to the powder and modeling liquid demonstrated below.

  The powder material for three-dimensional modeling has a base material, and a water-soluble organic material that covers the base material with an average thickness of 5 nm to 500 nm and can be dissolved and cross-linked by the action of a crosslinking agent-containing water as a modeling liquid. .

  In this three-dimensional modeling powder material, since the water-soluble organic material covering the base material can be dissolved and cross-linked by the action of the cross-linking agent-containing water, when the cross-linking agent-containing water is given to the water-soluble organic material, The water-soluble organic material dissolves and is crosslinked by the action of the crosslinking agent contained in the crosslinking agent-containing water.

  Thus, a thin layer (powder layer) is formed using the powder material for three-dimensional modeling, and a water-soluble solution is dissolved in the powder layer by discharging the crosslinking agent-containing water as the modeling liquid 10 to the powder layer. As a result of the crosslinking of the conductive organic material, the powder layer is bonded and cured, and the modeling layer 30 is formed.

  At this time, since the coating amount of the water-soluble organic material covering the substrate is 5 nm to 500 nm in average thickness, when the water-soluble organic material is dissolved, it exists in the necessary minimum amount around the substrate, and this is crosslinked. In order to form a three-dimensional network, the powder layer is cured with good dimensional accuracy and good strength.

  By repeating this operation, it is possible to easily and efficiently form a complicated three-dimensional object with high dimensional accuracy without causing deformation before sintering or the like.

-Base material-
The substrate is not particularly limited as long as it has a powder or particle form, and can be appropriately selected according to the purpose. Examples of the material include metals, ceramics, carbon, polymers, wood, biocompatible materials, etc., but from the viewpoint of obtaining a high-strength three-dimensional modeled object, a metal that can be finally sintered, Ceramics and the like are preferable.

  As a metal, stainless steel (SUS) steel, iron, copper, titanium, silver etc. are mentioned suitably, for example, As this stainless steel (SUS) steel, SUS316L etc. are mentioned, for example.

Examples of ceramics include metal oxides, and specific examples include silica (SiO ₂ ), alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), titania (TiO ₂ ), and the like.

  Examples of carbon include graphite, graphene, carbon nanotube, carbon nanohorn, and fullerene.

  Examples of the polymer include known resins that are insoluble in water.

  Examples of the wood include wood chips and cellulose.

  Examples of the biocompatible material include polylactic acid and calcium phosphate.

  These materials may be used alone or in combination of two or more.

As the substrate, commercially available particles or powders formed from these materials can be used. As a commercial item, for example, SUS316L (manufactured by Sanyo Special Steel, PSS316L), SiO ₂ (manufactured by Tokuyama, Excelica SE-15), AlO ₂ (manufactured by Daimei Chemical Co., Ltd., Tymicron TM-5D), ZrO ₂ (manufactured by Tosoh Corporation, TZ-B53).

  The substrate may be subjected to a known surface (modification) treatment for the purpose of increasing the affinity with the water-soluble organic material.

-Water-soluble organic materials-
The water-soluble organic material is not particularly limited as long as it is soluble in water and has a property capable of being crosslinked by the action of a crosslinking agent, in other words, as long as it is water-soluble and can be crosslinked by a crosslinking agent. Can be appropriately selected according to the purpose.

  Here, the water-solubility of the water-soluble organic material means that 90% by mass or more of the water-soluble organic material dissolves when 1 g of the water-soluble organic material is mixed with 100 g of water at 30 ° C. and stirred.

  Moreover, as a water-soluble organic material, the thing in which the viscosity in 20 degreeC of the 4 mass% (w / w%) aqueous solution is 40 mPa * s or less is preferable, and what is 1-35 Pa * s is more preferable, 5 Those having a viscosity of ˜30 mPa · s are particularly preferable.

  When the viscosity of the water-soluble organic material exceeds 40 mPa · s, a cured product (three-dimensional model, The strength of the cured product for sintering) may not be sufficient, and problems such as deformation of the shape may occur during subsequent processing such as sintering or handling. In addition, the dimensional accuracy of the cured product (stereolithic product, cured product for sintering) by the powder material (powder layer) for the three-dimensional model formed by adding the crosslinking agent-containing water to the three-dimensional model powder material is not sufficient. There is.

  The viscosity of the water-soluble organic material can be measured according to, for example, JISK7117.

-Crosslinker-containing water-
The crosslinking agent-containing water that is a modeling liquid is not particularly limited as long as it contains a crosslinking agent in an aqueous medium, and can be appropriately selected depending on the purpose. In addition, the crosslinking agent-containing water may contain other components appropriately selected as necessary in addition to the aqueous medium and the crosslinking agent.

  The other components can be appropriately selected in consideration of various conditions such as the type of means for applying the crosslinking agent-containing water, the usage frequency, and the amount. For example, when the crosslinking agent-containing water is applied by the liquid discharge method, the selection can be made in consideration of the influence of clogging on the nozzle of the liquid discharge head.

  Examples of the aqueous medium include water, alcohol such as ethanol, ether, ketone, and the like, and water is preferable. The aqueous medium may contain a small amount of components other than water such as alcohol.

  Compared with the configuration in which the binder for adhering the powder (base material) is discharged from the liquid discharge head by using the above-described powder material for a three-dimensional structure and water containing a crosslinking agent as a modeling liquid, the nozzle eye There is less clogging and the durability of the head is improved.

  Next, the control of the modeling operation by the control unit in the present embodiment will be described with reference to the flowchart of FIG.

  First, the modeling data of the first layer is read out, the powder 20 is supplied from the supply tank 21 to the modeling tank 22 and flattened by the flattening roller 12 to form the powder layer 31 (recoating). Then, the modeling layer 30 is formed by discharging the droplet 100 of the modeling liquid 10 from the head 50 while moving the ejection unit 51 according to the modeling data of the first layer.

  Thereafter, by the height sensor 561, the height of the surface (also referred to as a powder surface) of the modeling layer 30 and the height of the surface of the region other than the modeling layer of the powder layer 31 where the modeling layer 30 is not formed. Is detected. In addition, the area | region in which the modeling layer 30 is formed is also called a modeling part, and the part in which the modeling layer 30 is not formed is also called a non-modeling part. It is preferable to increase the detection accuracy by detecting the height by the height sensor 561 at at least two detection positions.

  Then, a difference (height difference) Δt between the height of the powder surface of the modeling layer 30 and the height of the powder surface in the region other than the modeling layer 30 is calculated and stored in the storage unit (for example, the RAM 503).

  Subsequently, the modeling stage 24 of the modeling tank 22 is raised in the Z1 direction by the stored difference Δt.

  Thereafter, the powder 20 at the height of the difference Δt is removed by the flattening roller 12, and the surface of the modeling layer 30 and the surface of the region of the powder layer 31 where the modeling layer 30 is not formed are aligned. Perform the operation (modeling surface out). At this time, the operating condition of the flattening roller 12 is preferably changed according to the height difference Δt.

  By this operation, the powder heights of the modeling part and the non-modeling part are aligned, the dent of the modeling part is eliminated, and the surface of the modeling part can be positioned on the outermost surface of the powder layer of the modeling tank.

  Thereafter, in the same manner as described in FIG. 6, the supply tank 21 side is raised, the modeling tank 22 side is lowered, the powder 20 is supplied to the modeling tank 22, and flattening is performed by the flattening roller 12. The powder layer 21 having a predetermined thickness (Δt1) on the modeling layer 30 is formed.

  And a modeling liquid is discharged according to the modeling data of the nth layer, and the modeling layer 30 of the nth layer is formed.

  Thereafter, it is determined whether or not there is data for the next modeling layer.

  Here, if there is data for the next modeling layer, the modeling tank 22 is raised in the Z1 direction by the stored difference Δt, the powder 20 of the difference Δt is removed, and the surface of the modeling layer 30 and the powder The process returns to the process of performing the operation (modeling surface forming) of aligning the height of the surface of the region of the layer 31 where the modeling layer 30 is not formed.

  If there is no data for the next modeling layer, the modeling operation is terminated.

  Next, this modeling operation will be specifically described with reference to FIGS. FIG. 8 thru | or FIG. 13 is explanatory drawing with which it uses for the description, (a) is a perspective explanatory drawing, (b) is a cross-sectional explanatory drawing.

  First, as shown in FIG. 8, the first modeling layer 30 is formed by discharging droplets from the head 50 to the powder layer 31 according to the modeling data of the first layer.

  At this time, when the powder density of the powder layer 31 is low, the surface of the modeling portion where the modeling layer 30 is formed is recessed compared to the surface of the non-modeling portion where the modeling layer 30 of the powder layer 31 is not formed. It will be.

  In this way, when the powder 20 is supplied while the modeling layer 30 is recessed to form the powder layer 31 of the next layer, the thickness of the powder supplied in the modeling part and the non-modeling part is different, and the resulting modeling is obtained. Density unevenness occurs in objects. Further, due to the dent formed at the boundary between the modeled part and the non-modeled part, the powder cannot be supplied to the end part of the modeled object, and the shape accuracy of the end part of the modeled object is lowered.

  Therefore, as shown in FIG. 9, after forming the first modeling layer 30 by the height sensor 561, before forming the next powder layer, the heights of the modeling part and the non-modeling part are adjusted. Detect. The height sensor 561 can be provided in the discharge unit 51 and can be moved together with the discharge unit, or can be arranged to be movable independently of the discharge unit 51.

  When performing this height detection, the positions of the modeling part and the non-modeling part are recognized from the image data of the first layer, and the respective powder surfaces (the surface of the modeling layer 30 and the modeling layer 30 are detected by the height sensor 561. The height of the other surface of the powder layer 31 is detected. At this time, in consideration of the unevenness of the powder surface, measurement is performed at at least two measurement points (detection positions).

  And the information (difference information) of the difference of the height of each powder surface calculated from the detection result is stored and held. Thus, by storing the difference information of the height obtained when the first modeling layer is formed, the modeling part and the non-modeling part in the second and subsequent layers that are the next and subsequent layers are stored. It can be used in an operation that aligns the height.

  Then, as shown in FIG. 10, the modeling stage 24 of the modeling tank 22 is raised by the difference.

  And as shown in FIG. 11, the powder 20 of the part higher than the modeling layer 30 (modeling part) is removed by the planarization roller 12, a dent is eliminated, and the height of the powder layer 31 and the height of the modeling layer 30 are removed. Align.

  Next, as shown in FIG. 12, in order to form the next powder layer, the supply stage 23 of the supply tank 21 is raised and the modeling stage 24 of the modeling tank 22 is lowered by a predetermined thickness, as shown in FIG. The powder 20 is supplied to the modeling tank 22 by the flattening roller 12 and flattened to form the next powder layer 31 having a predetermined thickness.

  Then, the operation | movement which forms the modeling layer 30 of the nth layer is performed, and modeling operation for a required layer is repeated, and a modeling part is modeled.

  By performing such a series of operations, it becomes possible to always form a powder layer with a constant layer thickness on the basis of the plane of the modeling part. Lamination thickness unevenness is suppressed.

  In addition, since the state in which the powder is placed in each stack is not different from the state of the first layer, the molding before performing the operation (leveling operation) of removing the powder corresponding to the height difference and aligning the height The detection amount of the first layer can be used as it is for the rising amount of the stage.

  Next, a second example of the three-dimensional modeling apparatus will be described with reference to FIGS. FIG. 14 is a perspective view of the main part of the apparatus, and FIG. 15 is a cross-sectional explanatory view of the modeling part, which is also described along with the modeling flow.

  This three-dimensional modeling apparatus is a powder layered modeling apparatus, and, similar to the three-dimensional modeling apparatus of the first example described above, a modeling part 1 in which a modeling layer to which powder is combined is formed, and a modeling liquid in the modeling part 1 And a modeling unit 5 as modeling means for modeling the three-dimensional model by discharging the liquid droplets.

  The modeling unit 1 includes only the modeling tank 22 and is configured to supply powder from the powder supply device to the modeling tank 22.

  The modeling unit 5 is supported so that the discharge unit 51 can reciprocate in the arrow X direction (this is referred to as “main scanning direction”) by guide members 54 and 55.

  Other configurations are the same as those of the three-dimensional modeling apparatus of the first example.

  In this three-dimensional modeling apparatus, as shown in FIG. 15A, modeling is performed by discharging droplets of the modeling liquid 10 from the head 50 of the discharge unit 51 to the powder 20 supplied on the modeling stage 24 of the modeling tank 22. Layer 30 is formed.

  At this time, the ejection unit 51 is moved in the main scanning direction to perform modeling for one scan (one scanning area), and then the modeling unit 5 is moved in the sub-scanning direction (Y1 direction) by one scan. By repeating the modeling for one scanning region, the modeling layer 30 for one layer is modeled. In addition, after modeling the modeling layer 30 for one layer, the modeling unit 5 is returned to the upstream side in the sub-scanning direction as shown in FIG.

  Then, in order to form the next modeling layer 30 on this modeling layer 30, the modeling stage 24 of the modeling tank 22 is moved down in the arrow Z2 direction by the thickness of one layer.

  Next, as shown in FIG. 15B, the powder 20 is supplied to the modeling tank 22 from the powder supply device. Then, while rotating the flattening roller 12, it is moved in the Y2 direction along the stage surface of the modeling stage 24 of the modeling tank 22 to form a powder layer 31 having a predetermined thickness on the modeling layer 30 of the modeling stage 24. (Flattening).

  Then, a droplet of the modeling liquid 10 is discharged from the head 50 of the discharge unit 51 to form the next modeling layer 30.

  As described above, the formation of the powder layer 31 and the solidification of the powder 20 by the discharge of the modeling liquid 10 are repeated to sequentially stack the modeling layers 30 to model a three-dimensional modeled object.

DESCRIPTION OF SYMBOLS 1 Modeling part 5 Modeling unit 10 Modeling liquid 12 Flattening roller (flattening means, rotating body)
20 Powder 21 Supply Tank 22 Modeling Tank 23 Supply Stage 24 Modeling Stage 30 Modeling Layer 31 Powder Layer 50 Liquid Discharge Head 51 Discharge Unit 561 Height Sensor (Height Detection Means)

Claims (9)

In the three-dimensional modeling apparatus for forming a three-dimensional model by sequentially laminating a modeling layer in which the powder of the powder layer is bonded to the powder layer by discharging droplets of the modeling liquid,
When forming the next powder layer on the powder layer on which the modeling layer is formed, before forming the next layer, the surface of the modeling layer and the powder on which the modeling layer is formed A three-dimensional modeling apparatus comprising means for performing an operation of aligning the height of the layer with the surface of the region where the modeling layer is not formed. Means for detecting the height of the area other than the modeling layer and the modeling layer;
The three-dimensional modeling apparatus according to claim 1, further comprising: means for calculating a difference in height between a surface of the modeling layer and a surface of a region other than the modeling layer of the powder layer. The three-dimensional modeling apparatus according to claim 2, wherein the height is detected by at least two detection positions by means of detecting the height. A modeling stage on which the modeling layer is laminated;
A flattening means that is relatively moved in a direction along the stage surface of the modeling stage, and planarizes the surface of the powder on the modeling stage to form the powder layer,
Means for performing the operation of aligning the height,
3. The apparatus according to claim 2, further comprising: raising the modeling stage by the difference in height, and performing an operation of removing the powder in a region where the modeling layer is not formed by the flattening unit. Or the three-dimensional modeling apparatus of 3. 5. The three-dimensional modeling apparatus according to claim 4, wherein the unit that performs the operation of aligning the height changes an operation condition of the flattening unit according to the difference in height. The means for performing the operation of aligning the height performs the operation of aligning the heights of the second and subsequent layers using the difference in height between the surface of the first powder layer and the surface of the modeling layer. The three-dimensional modeling apparatus according to claim 2, wherein the three-dimensional modeling apparatus is provided. The three-dimensional modeling apparatus according to any one of claims 2 to 6, wherein the means for detecting the height is movable together with the means for discharging the modeling liquid droplets. In the method for producing a three-dimensional structure, a three-dimensional structure is formed by sequentially laminating a modeling layer in which the powder of the powder layer is bonded to the powder layer by discharging droplets of the modeling liquid.
When forming the next powder layer on the powder layer on which the modeling layer is formed, before forming the next layer, the surface of the modeling layer and the powder on which the modeling layer is formed A method for producing a three-dimensional structure, characterized in that the height of the layer is uniform with the surface of a region where the modeling layer is not formed. A program for causing a computer to perform a modeling operation for discharging a droplet of a modeling liquid to a powder layer and sequentially stacking a modeling layer to which the powder of the powder layer is bonded to form a three-dimensional modeled object. There,
When forming the next powder layer on the powder layer on which the modeling layer is formed, before forming the next layer, the surface of the modeling layer and the powder on which the modeling layer is formed A program for causing a computer to perform a process of performing a control of aligning the height of the layer with the surface of a region where the modeling layer is not formed.

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