JP2020055235A - Lamination molding apparatus and method for manufacturing lamination molded article - Google Patents

Abstract

To provide a lamination molding apparatus capable of adjusting a preheating time on a powder.SOLUTION: A lamination molding apparatus 1 includes: a powder holding unit 5 capable of holding a powder bed A containing a powder 2; an energy imparting unit 8 imparting energy to the powder 2 held by the powder holding unit 5; a holding unit moving mechanism 14 moving the powder holding unit 5 in a direction X along the surface of the powder bed A; a preheating heater 15, 16 arranged in a front or rear side of the energy imparting unit 8 in the movement direction of the powder holding unit 5, and arranged to cover the powder bed A; and a control unit 31 controlling the movement of the powder holding unit 5 by use of the holding unit moving mechanism 14 so as to control a preheating time by the preheating heater 15, 16.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an additive manufacturing apparatus and a method for manufacturing an additive manufacturing object.

  The additive manufacturing apparatus can input a thermal energy to a powder, which is a material, and melt or sinter the powder to manufacture a shaped article. The additive manufacturing apparatus includes, for example, a molding table that holds powder and a molded object, and a heating element that inputs thermal energy to the powder (for example, see Patent Documents 1 and 2). For example, an additive manufacturing apparatus provided with a plurality of heating elements is known.

JP 2006-534903 A JP-T-2006-526098

  In the additive manufacturing apparatus, the powder may be preheated before applying energy to the powder. By maintaining the surface of the powder bed at a high temperature, thermal deformation of the modeled object can be suppressed. The present disclosure describes an additive manufacturing apparatus capable of suppressing a deterioration in quality by adjusting a preheating time for a powder, and a method for manufacturing an additive manufactured article.

  The additive manufacturing apparatus according to the present disclosure has a powder holding unit capable of holding a powder bed containing powder, an energy applying unit that applies energy to the powder held by the powder holding unit, and a powder along a surface of the powder bed. A holding unit moving mechanism for moving the holding unit, a preheater arranged at least one of the front side and the rear side of the energy applying unit in the moving direction of the powder holding unit, and arranged to cover the powder bed; A control unit that controls the movement of the powder holding unit using a mechanism to control the preheating time by the preheating heater.

  According to the additive manufacturing apparatus, it is possible to apply energy to the powder and sinter or melt the powder while moving the powder holding unit in a direction along the surface of the powder bed. According to the additive manufacturing apparatus, the powder holding unit can be moved to the position of the preheater to preheat the powder bed. The control unit can control the movement of the powder holding unit and adjust the preheating time by the preheating heater. As a result, the thermal deformation of the modeled object can be reduced, and a modeled object with improved quality can be manufactured. The powder bed includes a powder laminate.

  The control unit may control a stop time, which is a time for continuing the state in which the powder holding unit is stopped, at a position related to the preheater. Thus, the preheating time by the preheating heater can be adjusted by controlling the stop time of the powder holding unit. The control unit may extend the stopping time of the powder holding unit to increase the preheating time, or may shorten the stopping time of the powder holding unit and decrease the preheating time. The position related to the preheater includes, for example, a position where the powder bed can be preheated by the preheater.

  The control unit may control the moving speed of the powder holding unit during preheating by the preheating heater. The control unit may decrease the moving speed of the powder holding unit to increase the preheating time, or may increase the moving speed of the powder holding unit to decrease the preheating time.

  The additive manufacturing apparatus includes a powder supply unit disposed in front of the energy application unit in the moving direction and supplies powder to the powder holding unit, and the preheater is disposed in front of the powder supply unit in the movement direction. Is also good. According to the additive manufacturing apparatus, it is possible to supply the powder to the portion to which the energy is applied after the energy is applied to the powder by the energy applying unit while moving the powder holding unit. According to the additive manufacturing apparatus, the powder bed can be preheated after the energy is applied and the powder is supplied.

  In the additive manufacturing apparatus, in the movement direction, the powder supply unit may be disposed adjacent to the energy applying unit, and the preheater may be disposed adjacent to the powder supply unit. Thus, new powder can be supplied immediately after the energy is applied to the powder by the energy applying unit, and the powder can be preheated immediately after the powder is supplied.

  The preheating heater may include a first preheating heater and a second preheating heater arranged on both sides of the energy applying unit in the moving direction of the main body holding unit. The additive manufacturing apparatus can preheat the powder bed by moving the powder holding unit to the position of the first preheater after the energy is applied by the energy applying unit. After the preheating by the first preheater, the additive manufacturing apparatus can apply the energy by the energy applying unit by moving the powder holding unit in the opposite direction. In the additive manufacturing apparatus, after the energy is applied by the energy applying unit, the powder holding unit can be moved to the position of the second preheater to preheat the powder. In the additive manufacturing apparatus, after the preheating by the second preheater, the powder holding unit is further moved in the opposite direction, and the energy can be applied by the energy applying unit. According to the layered object, the application of energy and the preheating can be performed alternately by reciprocating the powder holding unit.

  The preheater may be disposed so as to cover the entire area of the surface of the powder bed in the moving direction, except for the energy application region by the energy application unit and the region below the supply port of the powder supply unit. Thus, the entire area of the surface of the powder bed except for the energy application area and the area below the supply port can be simultaneously preheated. As a result, a temperature difference on the surface of the powder bed can be suppressed.

  The method for manufacturing a layered object according to the present disclosure provides a preheating step of preheating a powder bed containing powder, and applying energy to the powder preheated in the preheating step while moving the powder bed in a direction along the surface of the powder bed. In the preheating step, the movement of the powder holding unit is controlled to control the preheating time.

  According to the method of manufacturing a layered product, the powder can be sintered or melted by applying energy to the powder while moving the powder holding unit in a direction along the surface of the powder bed. In the preheating step, the movement of the powder holding unit can be controlled to adjust the preheating time. As a result, the thermal deformation of the modeled object can be reduced, and a modeled object with improved quality can be manufactured.

  In the preheating step, at a position related to the preheating heater, a stop time that is a time for continuing the state in which the powder holding unit is stopped may be controlled. Thus, the preheating time by the preheating heater can be adjusted by controlling the stop time of the powder holding unit. In the preheating step, the preheating time may be increased by extending the stopping time of the powder holding unit, or the preheating time may be reduced by shortening the stopping time of the powder holding unit.

  In the preheating step, the moving speed of the powder holding unit may be controlled. In the preheating step, the moving speed of the powder holding unit may be decreased to increase the preheating time, or the moving speed of the powder holding unit may be increased to decrease the preheating time.

  A first energy applying step which is an energy applying step of applying energy to the powder while moving the powder bed in a first direction; and A first powder supply step of supplying new powder to the first step, a first preheating step of preheating the powder bed containing the powder supplied in the first powder supply step, and a first direction opposite to the first direction. While moving the powder bed in the second direction, the second energy applying step is an energy applying step of applying energy to the powder preheated in the first preheating step, and during the execution of the second energy applying step, A second powder supply step of supplying new powder on the powder to which energy has been applied, and a second preheating step of preheating a powder bed containing the powder supplied in the second powder supply step. May be included. In the method of manufacturing a laminate, energy can be applied to the powder by reciprocating the powder holding unit.

  In the preheating step, the entire area of the surface of the powder bed can be simultaneously preheated in the moving direction of the powder bed except for the energy application area in the energy application step and the area below the supply port of the powder supply unit. Thereby, the temperature difference on the surface of the powder bed can be suppressed. The energy application area is an area irradiated with the energy beam emitted from the energy application unit, and may include an area through which the energy beam passes.

  According to the present disclosure, since the movement of the powder holding unit can be controlled to adjust the preheating time for the powder, it is possible to suppress thermal deformation of the modeled object and suppress deterioration in the quality of the modeled object.

1 is a cross-sectional view illustrating an additive manufacturing apparatus according to an embodiment of the present disclosure. FIG. 2A is a sectional view when the additive manufacturing apparatus is viewed from above, and shows a state where the modeling tank is moving to the right. FIG. 2B is a cross-sectional view when the additive manufacturing apparatus is viewed from above, and shows a state where the modeling tank is moving to the left. FIG. 3A is a plan view showing a modeling tank arranged at a position corresponding to a preheater arranged on the right side. FIG. 3B is a plan view showing the modeling tank arranged at a position corresponding to the preheater arranged on the left side. 1 is a block diagram illustrating a controller according to the present disclosure. FIG. 5A is a cross-sectional view illustrating the additive manufacturing apparatus, and shows a state where the modeling tank is at the start position. FIG. 5B is a cross-sectional view illustrating the layered manufacturing apparatus, and shows a state where the modeling tank is present at the first stop position. FIG. 5C is a cross-sectional view showing the layered manufacturing apparatus, and shows a state in which the modeling tank exists near the center. FIG. 5D is a cross-sectional view illustrating the layered manufacturing apparatus, and shows a state in which the modeling tank exists at the second stop position. It is a flowchart which shows the procedure of the manufacturing method of a layered object, and shows from the preparation process to the process which stops a modeling tank at a 1st stop position. It is a flowchart which shows the procedure of the manufacturing method of a lamination model, and has shown from the process which preheats a powder bed with a 1st preheater to the process which stops a modeling tank at a 2nd stop position. It is a flowchart which shows the procedure of the manufacturing method of a lamination model, and has shown from the process which preheats a powder bed with a 2nd preheater to the process which stops a modeling tank at a 1st stop position. FIG. 9A is a diagram illustrating a state in which an electron beam is irradiated at the start position. FIG. 9B is a diagram illustrating a state in which powder is supplied by irradiating an electron beam while moving the modeling tank toward the first stop position. FIG. 9C is a diagram illustrating a state in which the first preheater is preheating. FIG. 9D is a diagram illustrating a state in which the movement of the modeling tank is restarted from the first stop position. FIG. 9E is a diagram showing a state in which powder is supplied by irradiating an electron beam while moving the modeling tank toward the second stop position. FIG. 9F is a diagram illustrating a state where the preheating is performed by the second preheating heater.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In each of the drawings, the same or corresponding portions have the same reference characters allotted, and overlapping description will be omitted.

  1 is a so-called 3D (three-dimensional) printer, which partially applies energy to the metal powders 2 arranged in a layered manner to form a metal powder 2. Can be sintered or melted. The shaping apparatus 1 can manufacture the three-dimensional shaped object 3 by repeating this.

  The modeled object 3 is, for example, a mechanical part or the like, and may be another structure. Examples of the metal powder 2 include titanium-based metal powder, Inconel (registered trademark) powder, aluminum powder, and stainless steel powder. The powder that is the material of the modeled object 3 is not limited to metal powder. The powder may be a powder containing carbon fibers and a resin, such as CFRP (Carbon Fiber Reinforced Plastics), or other powder. The powder may include a conductive powder having conductivity.

  The modeling apparatus 1 includes a vacuum chamber 4, a work table (powder holding unit) 5, a lifting device 6, a powder supply device (powder supply unit) 7, an electron beam irradiation device (energy applying unit) 8, and a controller 31. The vacuum chamber 4 is a container whose inside can be brought into a vacuum (low pressure) state, and is connected to a vacuum pump (not shown). The work table 5 is, for example, a powder holding unit that has a plate shape and on which the metal powder 2 as a material of the modeled object 3 is arranged. The metal powders 2 on the work table 5 are arranged, for example, in layers in a plurality of times. The work table 5 has, for example, a rectangular shape in plan view. The shape of the work table 5 is not limited to a rectangle, but may be a circle or another shape.

  The work table 5 is arranged in the modeling tank 10 in the vacuum chamber 4. In the modeling tank 10, the work table 5 is movable in the Z direction (vertical direction), and descends sequentially according to the number of layers of the metal powder 2. The side wall 10 a of the modeling tank 10 guides the movement of the work table 5. The side wall 10a has a rectangular tube shape (a cylindrical shape when the work table is circular) so as to correspond to the outer shape of the work table 5. The side wall 10 a of the modeling tank 10 and the work table 5 form a storage unit that stores the metal powder 2 and the modeled object 3. The work table 5 may constitute the bottom of the modeling tank 10.

  The elevating device 6 can elevate and lower the metal powder 2 on the work table 5 and the shaped object 3 in the course of manufacturing. The elevating device 6 includes, for example, a rack-and-pinion type driving mechanism, and moves the work table 5 in the Z direction. The elevating device 6 may include a bar-shaped vertical member (rack) 6a connected to the bottom surface of the work table 5 and extending downward, and a drive source 6b for driving the vertical member 6a. As the drive source 6b, for example, an electric motor can be used. A pinion may be provided on the output shaft of the electric motor, and a tooth profile that meshes with the pinion may be provided on a side surface of the vertical member 6a. The electric motor is driven, the pinion rotates, and power is transmitted, so that the vertical member 6a can move in the vertical direction. By stopping the rotation of the electric motor, the vertical member 6a is positioned, the position of the work table 5 in the Z direction is determined, and the position is maintained. The elevating device 6 is not limited to the rack and pinion type driving mechanism, but may be a device having another driving mechanism such as a ball screw and a cylinder.

  The powder supply device 7 may include a raw material tank 11 that is a storage unit that stores the metal powder 2 that is a raw material. The raw material tank 11 is disposed in the vacuum chamber 4. The raw material tank 11 is disposed above the work table 5 in the Z direction. The raw material tanks 11 are arranged, for example, on both sides of an irradiation area (energy applying area) D of an electron beam (electron beam) by the electron beam irradiation device 8 in the X direction crossing the Z direction. In FIG. 1, the irradiation area D of the electron beam is indicated by a two-dot chain line. The irradiation region D may include a region through which the electron beam emitted from the electron beam irradiation device 8 passes.

At the bottom of the raw material tank 11, a discharge port (supply port) 11a is provided. The discharge ports 11a are continuous, for example, in the Y direction as shown in FIGS. 2 (a) and 2 (b). The Y direction is a direction that intersects the X direction and the Z direction. The opening length of the discharge port 11a in the Y direction may be equal to the length of the work table 5 in the Y direction. In other words, the opening length of the discharge port 11a in the Y direction may be equal to the distance between the side walls 10a in the Y direction. The opening length of the discharge port 11a in the Y direction may be shorter than the length of the work table 5 in the Y direction, for example.

  Below the raw material tank 11, an overhang plate 12 extending laterally from the upper end of the side wall 10a of the modeling tank 10 may be provided. The overhang plate 12 forms a plane that intersects the Z direction around the work table 5.

  The powder supply device 7 may include a powder application mechanism (not shown) for leveling the metal powder 2. The powder application mechanism is relatively movable above the work table 5, and smoothes the surface (upper surface) 2 a of the uppermost layer of the laminate of the metal powder 2 on the work table 5. Hereinafter, the “laminate of the metal powder 2” is referred to as a powder bed A. The lower end of the powder application mechanism can contact the surface 2a of the powder bed A to make the height uniform. The powder application mechanism has, for example, a plate shape and a predetermined width in the Y direction. The length of the powder application mechanism in the Y direction corresponds to, for example, the total length of the work table 5 in the Y direction. The modeling device 1 may be configured to include a roller, a rod-shaped member, a brush portion, and the like, instead of the powder application mechanism.

  The electron beam irradiation device 8 includes an electron gun (not shown) that irradiates an electron beam as an energy beam. The electron beam emitted from the electron gun is irradiated into the vacuum chamber 4 to heat the metal powder 2. The electron beam irradiation device 8 can apply energy to heat and melt or sinter the metal powder 2. The electron beam irradiation device 8 is an energy applying unit that applies energy to the powder bed A.

  The electron beam irradiation device 8 may include a coil unit that controls irradiation of an electron beam. The coil unit can include, for example, an aberration coil, a focus coil, and a deflection coil. The aberration coil is installed around the electron beam emitted from the electron gun and converges the electron beam. The focus coil is provided around the electron beam emitted from the electron gun, and corrects a shift in the focus position of the electron beam. The deflection coil is installed around the electron beam emitted from the electron gun, and adjusts the irradiation position of the electron beam. Since the deflection coil performs electromagnetic beam deflection, the scanning speed at the time of electron beam irradiation can be higher than that of mechanical beam deflection. The electron gun and the coil unit are arranged on the upper part of the vacuum chamber 4. The electron beam emitted from the electron gun is converged by the coil unit, the focal position is corrected, the scanning speed is controlled, and reaches the irradiation position of the metal powder 2.

  The modeling apparatus 1 includes a modeling tank moving mechanism (holding unit moving mechanism) 14, a first preheater 15, a second preheater 16, and a controller 31. The modeling tank moving mechanism 14 can move the modeling tank 10 in the X direction. The modeling tank moving mechanism 14 can integrally move the modeling tank 10, the work table 5, and the elevating device 6. The modeling tank 10, the work table 5, and the elevating device 6 are connected by, for example, a frame 17. The frame 17 may include a first support member 17a and a second support member 17b.

  The first support member 17a may be disposed around the modeling tank 10 and extend in the Z direction. The upper end of the first support member 17a is connected to, for example, the overhang plate 12. The modeling tank 10 is supported by the first support member 17a via, for example, the overhang plate 12. The second support member 17b may form the bottom of the frame 17. The second support member 17b connects lower end portions of the first support member 17a to each other. The second support member 17b supports, for example, the lifting device 6. The work table 5 is supported, for example, by the vertical member 6a, and is supported by the second support member 17b via the lifting device 6.

  The modeling tank moving mechanism 14 may include, for example, a rack and pinion type driving mechanism. The modeling tank moving mechanism 14 may include a pair of guide rails 14a. As shown in FIGS. 2A and 2B, the pair of guide rails 14a are separated in the Y direction and extend in the X direction. The pair of guide rails 14a may be disposed on a bottom plate of the vacuum chamber 4, for example.

  The modeling tank moving mechanism 14 may include a driving source 14b. For example, an electric motor can be used as the drive source 14b. The output shaft of the electric motor is provided with a pinion, and one guide rail 14a is provided with a tooth profile (rack) that meshes with the pinion. The drive source 14b is attached to, for example, the bottom of the frame 17. Further, a driven roller that rotates and moves along the other guide rail 14a may be attached to the frame 17. When the electric motor is driven to rotate the pinion, the frame 17, the lifting device 6, the work table 5, and the modeling tank 10 can move in the X direction as a unit. The moving direction of the modeling tank moving mechanism 14 is not limited to the X direction, but may be the Y direction, or may be a direction inclined with respect to the X direction and the Y direction. The modeling tank moving mechanism 14 is not limited to a mechanism including a rack-and-pinion type driving mechanism, and may include, for example, other driving mechanisms such as a ball screw and a cylinder.

  The first preheater 15 and the second preheater 16 are arranged on both sides of the electron beam irradiation device 8 in the X direction. For example, when the modeling tank 10 moves from the side where the second preheater 16 is present to the side where the first preheater 15 is present, the side where the first preheater 15 is present is the front side, and the second preheater is present. The side where the heater 16 exists is the rear side. When the position of the electron beam irradiation device 8 is centered, the first preheating heater 15 and the second preheating heater 16 are arranged outside the electron beam irradiation device 8 in the X direction. The first preheater 15 and the second preheater 16 are arranged outside the discharge port 11 a of the raw material tank 11. In the X direction, the second preheater 16, the discharge port 11a, the electron beam irradiation device 8, the discharge port 11a, and the first preheater 15 are arranged in this order from right to left in the drawing.

  As shown in FIG. 1, the discharge port 11a is arranged adjacent to the electron beam irradiation area D in the X direction. The first preheater 15 may be arranged adjacent to the discharge port 11a in the X direction. The second preheater 16 may be arranged adjacent to the discharge port 11a in the X direction.

  As shown in FIGS. 3A and 3B, the first preheater 15 and the second preheater 16 may be arranged so as to cover the powder bed A. The size of the first preheater 15 may match the size of the powder bed A in plan view, or may be larger than the powder bed A. The first preheater 15 may coincide with a region surrounded by the side wall 10a of the modeling tank 10 in plan view, or may be larger than a region surrounded by the side wall 10a. The size of the second preheater 16 is the same as the size of the first preheater 15.

  The first preheater 15 and the second preheater 16 may be arranged so as to cover the entire area of the surface 2a of the powder bed A except for a predetermined area. The first preheater 15 and the second preheater 16 are arranged so as to cover the entire area of the surface 2a of the powder bed A in the X direction except for the electron beam irradiation area D and the area below the discharge port 11a. May be.

  The first preheater 15 and the second preheater 16 have, for example, a plate shape. The first preheater 15 and the second preheater 16 may include, for example, a heating element based on electric resistance. The first preheating heater 15 and the second preheating heater 16 may include a lamp heater. The first preheater 15 and the second preheater 16 can pre-sinter the surface 2 a of the powder bed A by preheating the metal powder 2.

  The controller 31 illustrated in FIG. 4 is a control unit that controls the entire apparatus of the modeling apparatus 1. The controller 31 is a computer including hardware such as a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), and software such as a program stored in the ROM. The controller 31 includes an input signal circuit, an output signal circuit, a power supply circuit, and the like. The controller 31 includes a calculation unit 32 and a memory 33. The controller 31 is electrically connected to the electron beam irradiation device 8, the powder supply device 7, the elevating device 6, the modeling tank moving mechanism 14, the first preheater 15, and the second preheater 16. The controller 31 can generate various command signals. The memory 33 can store data necessary for various controls.

  The arithmetic unit 32 transmits a command signal to the electron beam irradiation device 8 to control the irradiation timing and irradiation position of the electron beam (irradiation control). The calculation unit 32 controls the irradiation of the electron beam when the metal powder 2 is melted. The arithmetic unit 32 can transmit a command signal to the powder supply device 7 to control the supply timing and supply amount of the metal powder 2. The calculation unit 32 may transmit a command signal to the powder coating mechanism to control the operation timing of the powder coating mechanism.

  The arithmetic unit 32 can control the modeling tank moving mechanism 14 by transmitting a command signal to the modeling tank moving mechanism 14. The calculation unit 32 can control the movement start timing of the modeling tank 10. The calculation unit 32 can control the moving time and the moving speed of the modeling tank 10. The calculation unit 32 may control the stop position of the modeling tank 10. The calculation unit 32 can control the stop time of the modeling tank 10. The stop time is the time during which the molding tank 10 is stopped at the position of the first preheater 15, and the time during which the molding tank 10 is stopped at the position of the second preheater 16. Including time spent. The controller 31 can control the stop time of the modeling tank 10 and adjust the preheat time of the first preheater 15 and the second preheater 16.

  The calculation unit 32 may transmit a command signal to the first preheater 15 to control the temperature, operation start, operation stop, and the like of the first preheater 15. The calculation unit 32 may transmit a command signal to the second preheater 16 to control the temperature, operation start, operation stop, and the like of the second preheater 16.

  In FIG. 5A, the modeling tank 10 is arranged, for example, at a start position. For example, a position where the position on the inner surface side of the left side wall 10a exists directly below the electron beam irradiation device 8 can be set as the start position. In the start position, for example, a position on the inner surface side of the right side wall 10a may be present immediately below the electron beam irradiation device 8. Another position may be the start position.

  In FIG. 5B, the modeling tank 10 is disposed at the first stop position. For example, a position where the modeling tank 10 exists immediately below the first preheater 15 can be set as a first stop position. At the first stop position, the surface 2 a of the powder bed A is covered by the first preheater 15. At this time, the entire area of the surface 2 a of the powder bed A may be covered by the first preheater 15.

  The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to move the modeling tank 10 from the start position to the first stop position. The controller 31 can transmit a command signal to the electron beam irradiation device 8 while moving the modeling tank 10 to irradiate the powder bed A with an electron beam. The controller 31 can preheat the powder bed A by the first preheater 15 while moving the modeling tank 10. The controller 31 may transmit a command signal to the first preheater 15 to control ON / OFF of the first preheater 15. The controller 31 can lower the work table 5 by transmitting a command signal to the elevating device 6 when the modeling tank 10 is stopped at the first stop position. The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to restart the movement of the modeling tank 10. Here, the direction of movement of the modeling tank 10 may be a direction (for example, rightward) opposite to a direction (for example, leftward) from the start position to the first stop position.

  In FIG. 5C, in the X direction, the central portion of the modeling tank 10 is disposed immediately below the electron beam irradiation device 8. In FIG. 5D, the modeling tank 10 is located at the second stop position. For example, the position where the modeling tank 10 exists immediately below the second preheater 16 can be set as the second stop position. At the second stop position, the surface 2 a of the powder bed A is covered by the second preheater 16. At this time, the entire area of the surface 2 a of the powder bed A may be covered by the second preheater 16.

  The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to move the modeling tank 10 from the start position to the second stop position. The controller 31 can transmit a command signal to the electron beam irradiation device 8 while moving the modeling tank 10 to irradiate the powder bed A with an electron beam. The controller 31 can preheat the powder bed A by the second preheater 16 while moving the modeling tank 10. The controller 31 may transmit a command signal to the second preheater 16 to control ON / OFF of the second preheater 16. When the modeling tank 10 is stopped at the second stop position, the controller 31 can send a command signal to the elevating device 6 to lower the work table 5. The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to restart the movement of the modeling tank 10. The direction of movement of the modeling tank 10 here can be a direction (for example, leftward) opposite to a direction (for example, rightward) from the first stop position to the second stop position.

  The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to move the modeling tank 10 from the second stop position to the first stop position. The controller 31 can transmit a command signal to the electron beam irradiation device 8 while moving the modeling tank 10 to irradiate the powder bed with an electron beam.

  Next, a method of manufacturing a layered product will be described. 6 to 8 are flowcharts showing the procedure of the method for manufacturing a layered object. FIG. 6 shows a process from the preparation process to the process of stopping the modeling tank at the first stop position. FIG. 7 shows the steps from the step of preheating the powder bed A by the first preheater to the step of stopping the modeling tank at the second stop position. FIG. 8 shows the steps from the step of preheating the powder bed A by the second preheater to the step of stopping the modeling tank at the first stop position.

  First, a preparation process is performed (Step S1). Here, the metal powder 2 is supplied onto the work table 5 to form a powder bed A on the work table 5. The controller 31 transmits a command signal to the modeling tank moving mechanism 14 and the powder supply device 7 to supply the metal powder 2 onto the work table 5 while moving the modeling tank 10 (powder supply step). For example, the first-layer metal powder 2 can be formed.

  Next, the powder bed A is preheated (step S2, preheating step). The controller 31 can transmit a command signal to the second preheater 16 to operate the second preheater and preheat the powder bed A. Here, the controller 31 can transmit a command signal to the modeling tank moving mechanism 14 and preheat the powder bed A while moving the modeling tank 10. For example, the powder bed A can be preheated by the second preheater 16 while moving the modeling tank 10 directly below the second preheater 16. The controller 31 may stop the modeling tank 10 immediately below the second preheater 16 and adjust the preheating time. The controller 31 may lower the work table 5 when the modeling tank 10 is stopped immediately below the second preheater 16. Thereby, a space in which the second-layer metal powder 2 is arranged can be secured. The controller 31 may adjust the amount of heat transmitted to the powder bed A by changing the distance between the work table 5 and the second preheater 16 in the Z direction, for example.

  Next, the modeling tank 10 is arranged at a start position (step S3). The controller 31 can transmit a command signal to the modeling tank moving mechanism 14 to move the modeling tank 10 and arrange it at the start position shown in FIG. 9A.

  Next, electron beam irradiation is started (step S4, energy applying step). The controller 31 can transmit a command signal to the electron beam irradiation device 8 and irradiate the electron beam to melt the metal powder 2. The position where the electron beam is irradiated is set in advance according to the shape of the modeled object 3. Data relating to the position where the electron beam is irradiated is stored in the memory 33, for example. The controller 31 can irradiate the electron beam while moving the modeling tank 10.

  Next, the metal powder 2 is supplied while moving the modeling tank 10 (Step S5). Here, the controller 31 transmits a command signal to the modeling tank moving mechanism 14, and moves the modeling tank 10 toward the first stop position (in the first direction) as shown in FIG. 9B. Let it. During the movement of the modeling tank 10, the irradiation of the electron beam by the electron beam irradiation device 8 is continued (first energy applying step). The controller 31 transmits a command signal to the powder supply device 7, supplies new metal powder 2 onto the surface 2a of the powder bed A irradiated with the electron beam, and forms a new surface 2a (No. 1 powder supply step). For example, the metal powder 2 can be supplied from a raw material tank 11 disposed in front of the electron beam irradiation device 8 in the traveling direction of the modeling tank 10. In FIG. 9B, the traveling direction of the modeling tank 10 is leftward, and the metal powder 2 can be supplied from the left raw material tank 11 disposed in front of the electron beam irradiation device 8. Thereby, new metal powder 2 can be supplied onto the portion of the powder bed A irradiated with the electron beam. For example, in a state in which the first layer of metal powder 2 is irradiated with the electron beam, the metal powder 2 is supplied onto the portion of the first layer of metal powder 2 irradiated with the electron beam and the two layers Eyes are formed.

  During the movement of the modeling tank 10, the powder bed A is preheated by the first preheater 15 (step S6, first preheating step). The controller 31 can transmit a command signal to the first preheater 15 to operate the first preheater and preheat the powder bed A. The molding tank 10 moves, and the powder bed A existing immediately below the first preheater 15 is preheated by the first preheater 15.

  After moving the modeling tank 10 and irradiating the electron beam at a predetermined position, the irradiation of the electron beam is stopped. When the modeling tank 10 moves to a predetermined position, the supply of the metal powder 2 is stopped. (Step S7). When the irradiation of the electron beam at the scheduled position is completed, the controller 31 stops the irradiation of the electron beam. After supplying the metal powder 2 to all the regions of the modeling tank 10, the controller 31 stops supplying the metal powder 2. The movement of the modeling tank 10 and the preheating by the first preheating heater 15 are continued.

  Next, the modeling tank 10 is stopped at the first stop position (Step S8). The movement of the modeling tank 10 is continued, and as shown in FIG. 9C, when the modeling tank 10 reaches the first stop position, the movement of the modeling tank 10 is stopped. The controller 31 can stop the modeling tank 10 by transmitting a command signal to the modeling tank moving mechanism 14. The controller 31 can stop driving of the electric motor in the modeling tank moving mechanism 14.

  Next, the process proceeds to step S11 shown in FIG. In step S11, the powder bed A is preheated by the first preheater 15 while the modeling tank 10 is stopped at the first stop position (first preheating step). The controller 31 can adjust the time during which the modeling tank 10 is stopped at the first stop position. Thereby, the preheating time by the first preheating heater 15 can be adjusted. The preheating time by the first preheater 15 is the time during which the modeling tank 10 is moving to the first stop position, the time during which the modeling tank 10 is stopped at the first stop position, and the time when the modeling tank 10 is moving from the first stop position. And the time until the powder bed no longer exists immediately below the first preheater 15 may be included. The modeling tank 10 can adjust the preheating time by controlling the stop time of the modeling tank 10. The controller 31 may increase the preheating time by extending the stop time of the modeling tank 10 at the first stop position. The controller 31 may reduce the preheating time by shortening the stop time of the modeling tank 10 at the first stop position.

  Next, as shown in FIG. 9D, the work table 5 is lowered at the first stop position (step S12). The controller 31 can send a command signal to the lifting device 6 to lower the work table 5. Thereby, a space for disposing the third-layer metal powder 2 can be secured. The controller 31 may adjust the amount of heat transferred to the powder bed A by changing the distance between the work table 5 and the first preheater 15 in the Z direction, for example.

  Next, the movement of the modeling tank 10 is restarted (step S13). The controller 31 transmits a command signal to the modeling tank moving mechanism 14 to restart the movement of the modeling tank 10. After the elapse of the stop time at the first stop position, the controller 31 moves the modeling tank 10 in the opposite direction (in the second direction). The modeling tank moving mechanism 14 moves the modeling tank 10 from the first stop position to the second stop position.

  Next, electron beam irradiation is restarted (step S14, energy applying step). The controller 31 transmits a command signal to the electron beam irradiation device 8 and irradiates the electron beam to melt the metal powder 2. As shown in FIG. 9E, the controller 31 irradiates the preset position with the electron beam while moving the modeling tank 10 toward the second stop position (second energy applying step). The electron beam irradiator 8 irradiates the position of the powder bed A located immediately below the electron beam irradiator 8 with an electron beam.

  Next, the metal powder 2 is supplied while moving the modeling tank 10 toward the second stop position (Step S15, second powder supply step). Here, the controller 31 transmits a command signal to the powder supply device 7 to supply the metal powder 2 onto the powder bed A, and forms a new powder bed A. For example, the metal powder 2 can be supplied from a raw material tank 11 disposed in front of the electron beam irradiation device 8 in the traveling direction of the modeling tank 10. In FIG. 9 (e), the direction of movement of the modeling tank 10 is rightward, and the metal powder 2 can be supplied from the right material tank 11 disposed in front of the electron beam irradiation device 8. Thereby, the metal powder 2 can be supplied onto the portion of the powder bed A irradiated with the electron beam. For example, in a state where the second layer of metal powder 2 is irradiated with the electron beam, the metal powder 2 is supplied onto the portion of the second layer of metal powder 2 that has been irradiated with the electron beam and the three layers of metal powder 2 are supplied. Eyes are formed.

  During the movement of the modeling tank 10, the powder bed A is preheated by the second preheater 16 (step S16, second preheating step). The controller 31 can transmit a command signal to the second preheater 16 to operate the second preheater 16 to preheat the powder bed A. The molding tank 10 moves, and the powder bed A existing immediately below the second preheater 16 is preheated by the second preheater 16.

  After moving the modeling tank 10 and irradiating the electron beam at a predetermined position, the irradiation of the electron beam is stopped. When the modeling tank 10 moves to a predetermined position, the supply of the metal powder 2 is stopped. (Step S17). When the irradiation of the electron beam at the scheduled position is completed, the controller 31 stops the irradiation of the electron beam. After supplying the metal powder 2 to all the regions of the modeling tank 10, the controller 31 stops supplying the metal powder 2. The movement of the modeling tank 10 and the preheating by the second preheater 16 are continued.

  Next, the modeling tank 10 is stopped at the second stop position (Step S18). Movement of the modeling tank 10 is continued, and when the modeling tank 10 reaches the second stop position as shown in FIG. 9F, the movement of the modeling tank 10 is stopped. The controller 31 transmits a command signal to the modeling tank moving mechanism 14 to stop the modeling tank 10.

  Next, the process proceeds to step S21 shown in FIG. In step S21, the powder bed A is preheated by the second preheater 16 while the modeling tank 10 is stopped at the second stop position (second preheating step). The controller 31 can adjust the time during which the modeling tank 10 is stopped at the second stop position. Thereby, the preheating time by the second preheating heater 16 can be adjusted. The preheating time by the second preheater 16 is the time during which the modeling tank 10 is moving to the second stop position, the time during which the modeling tank 10 is stopped at the second stop position, and the time when the modeling tank 10 is moving from the second stop position. And the time until the powder bed no longer exists immediately below the second preheater 16. The modeling tank 10 can adjust the preheating time by controlling the stop time of the modeling tank 10. The controller 31 may increase the preheating time by extending the stop time of the modeling tank 10 at the second stop position. The controller 31 may reduce the preheating time by shortening the stop time of the modeling tank 10 at the first stop position.

  Next, the work table 5 is lowered at the first stop position (step S22). The controller 31 can send a command signal to the lifting device 6 to lower the work table 5. Thereby, a space in which the fourth-layer metal powder 2 is arranged can be secured.

  Next, the movement of the modeling tank 10 is restarted (step S23). The controller 31 transmits a command signal to the modeling tank moving mechanism 14 to restart the movement of the modeling tank 10. After the elapse of the stop time at the second stop position, the controller 31 moves the modeling tank 10 from the second stop position toward the first stop position.

  Next, electron beam irradiation is restarted (step S24, energy applying step). The controller 31 transmits a command signal to the electron beam irradiation device 8 and irradiates the electron beam to melt the metal powder 2. As shown in FIG. 9B, the controller 31 irradiates the predetermined position with the electron beam while moving the modeling tank 10 toward the first stop position (first energy applying step). The electron beam irradiator 8 irradiates the position of the powder bed A located immediately below the electron beam irradiator 8 with an electron beam.

  Next, the metal powder 2 is supplied while moving the modeling tank 10 toward the first stop position (Step S25, first powder supply step). Here, the same procedure as in step S5 is performed. For example, in a state where the third layer of metal powder 2 is irradiated with an electron beam, the metal powder 2 is supplied onto the portion of the third layer of metal powder 2 irradiated with the electron beam and the four layers of metal powder are supplied. Eyes are formed.

  During the movement of the modeling tank 10, the powder bed A is preheated by the first preheater 15 (step S26, first preheating step). Here, the same procedure as in step S6 is performed.

  After moving the modeling tank 10 and irradiating the electron beam at a predetermined position, the irradiation of the electron beam is stopped. When the modeling tank 10 moves to a predetermined position, the supply of the metal powder 2 is stopped. (Step S27). Here, the same procedure as in step S7 is performed.

  Next, the modeling tank 10 is stopped at the first stop position (Step S28). Here, the same procedure as in step S8 is performed.

  Then, the steps from step S11 to step S18 shown in FIG. 7 and the steps from step S21 to step S28 shown in FIG. 8 are executed alternately. Modeling is performed for all layers of the modeled object 3, and the modeling of the modeled object 3 is completed.

  According to the shaping apparatus 1, the powder can be melted by applying energy to the powder while moving the shaping tank 10 in the X direction. According to the molding apparatus 1, the molding tank 10 can be moved to the positions of the first preheater 15 and the second preheater 16 to preheat the powder bed. The controller 31 can control the movement of the modeling tank 10 to adjust the preheating time.

  According to the modeling apparatus 1, the preheating time of the first preheating heater 15 and the second preheating heater 16 can be adjusted by controlling the stop time of the modeling tank 10. The controller 31 can extend the stop time of the modeling tank 10 to increase the preheating time, and can shorten the stop time of the modeling tank 10 to reduce the preheating time.

  In the molding apparatus 1, since the electron beam irradiation device 8, the raw material tank 11, and the first preheater 15 are arranged adjacent to each other in the moving direction of the molding tank 10, the electron beam is emitted while moving the molding tank 10. The metal powder 2 can be supplied to the portion irradiated with the electron beam. Thereby, the heat of the portion of the metal powder 2 heated by the electron beam can be transmitted to the metal powder 2 supplied thereon. Since new metal powder 2 is supplied on the portion heated by the electron beam, heat loss due to radiant heat from the portion heated by the electron beam can be suppressed. Further, in the molding apparatus 1, the metal powder 2 can be preheated by the first preheater 15 immediately after the metal powder 2 is newly supplied. At this time, in the modeling apparatus 1, in the moving direction of the modeling tank 10, the powder bed A is preheated by the first preheater 15 disposed in front of the electron beam irradiation position, and is disposed behind the electron beam irradiation position. The powder bed A can be preheated and kept warm by the second preheater 16 thus set.

  In the shaping apparatus 1, since the electron beam irradiation device 8, the raw material tank 11, and the second preheater 16 are arranged adjacent to each other in the moving direction of the shaping tank 10, the electron beam is emitted while moving the shaping tank 10. The metal powder 2 can be supplied to the portion irradiated with the electron beam. Thereby, the heat of the portion of the metal powder 2 heated by the electron beam can be transmitted to the metal powder 2 supplied thereon. Since new metal powder 2 is supplied on the portion heated by the electron beam, heat loss due to radiant heat from the portion heated by the electron beam can be suppressed. Further, in the molding apparatus 1, the metal powder 2 can be preheated by the first preheater 15 immediately after the metal powder 2 is newly supplied. At this time, in the shaping apparatus 1, in the moving direction of the shaping tank 10, the powder bed A is preheated by the second preheater 16 arranged in front of the irradiation position of the electron beam, and is arranged behind the irradiation position of the electron beam. The powder bed A can be preheated and kept warm by the first preheater 15 thus set.

  In the modeling apparatus 1, the discharge port 11a is arranged adjacent to the electron beam irradiation region D in the X direction. In the shaping apparatus 1, a first preheater 15 and a second preheater 16 are arranged adjacent to the discharge port 11a in the X direction. Accordingly, the electron beam irradiation device 8, the raw material tank 11, the first preheater 15 and the second preheater 16 are compactly arranged in the moving direction of the modeling tank 10, and the enlargement of the vacuum chamber 4 can be suppressed.

  According to the modeling apparatus 1, irradiation of the electron beam, supply of the metal powder 2, and preheating of the metal powder 2 can be repeatedly performed by reciprocating the modeling tank 10.

  In the modeling apparatus 1, a first preheater 15 and a second preheater 16 are arranged on both sides of the electron beam irradiation area D in the moving direction of the modeling tank 10. The surface 2 a of the powder bed A is covered by the first preheater 15 or the second preheater 16 in almost all areas in the movement range of the modeling tank 10. Thereby, the powder bed A can always be preheated regardless of the position of the modeling tank 10 in the movement range of the modeling tank 10.

  In the modeling apparatus 1, the surface 2a of the powder bed A can be preheated by using the first preheater 15 and the second preheater 16, and the powder bed A heated to a predetermined temperature can be kept warm. In the modeling apparatus 1, the temperature of the modeling surface can be maintained at a high temperature, so that the thermal deformation of the modeled object 3 can be reduced. The “modeling surface” includes a surface that becomes an object 3 when energy is applied to the surface 2 a of the powder bed A to be melted or sintered. In the modeling apparatus 1, since the temperature of the modeling surface can be maintained at a high temperature, generation of smoke from the powder bed A can be suppressed. In the modeling apparatus 1, the quality of the modeled object 3 can be improved by alleviating the thermal deformation of the modeled object 3 and suppressing the generation of smoke from the powder bed A.

  In the modeling apparatus 1, the powder bed A can be irradiated with the electron beam, supplied with the metal powder 2, and preheated in parallel while moving the modeling tank 10. In the modeling apparatus 1, the manufacturing time of the modeled object 3 can be reduced as a whole.

  The present disclosure is not limited to the embodiments described above, and various modifications as described below are possible without departing from the gist of the present disclosure.

  In the above-described modeling apparatus, the modeling tank 10 is moved in the X direction. However, for example, a modeling apparatus having a modeling tank moving mechanism that moves the modeling tank 10 in the X direction and the Y direction may be used. For example, in a modeling apparatus provided with one electron gun, an area that can be irradiated with an electron beam can be enlarged. The modeling device may include a plurality of electron guns. For example, a plurality of electron guns may be arranged in a direction crossing the movement direction of the modeling tank 10.

  In the above-described modeling apparatus, a configuration is provided in which a plurality of raw material tanks 11 are provided.

  The modeling device 1 may include another heating unit that heats the molding tank 10 from the side or below. For example, an induction heating type or resistance heating type heater may be provided on the outside of the side wall of the modeling tank 10 or on the work table 5, and the heater may be used to preheat and keep the powder warm.

  In the above embodiment, the powder is melted by irradiating the electron beam. However, the beam irradiated to the powder is not limited to the electron beam, and may be another energy beam (for example, a laser). The shaping apparatus 1 may be provided with, for example, a laser transmitter (heat source irradiation device) and irradiate a laser beam to melt the powder. The modeling device that irradiates the laser beam may include a chamber for holding an inert gas atmosphere instead of the vacuum chamber 4. Further, the heat source irradiation device that irradiates the laser beam functions as a heating unit for melting when the powder is melted. In this case, the heat source irradiation device may be configured to include, for example, a mirror that polarizes the laser beam, and an optical component such as a driving unit for moving the mirror and a condenser lens.

  In the above embodiment, the powder bed A is preheated by using the first preheater 15 and the second preheater 16, but in addition to the preheat by the first preheater 15 and the second preheater 16, an electron beam is also supplied. Irradiation may be used to preheat powder bed A, laser beam irradiation may be used to preheat powder bed A, or another method may be used to preheat powder bed A.

1 Molding equipment (Lamination molding equipment)
2 Metal powder 2a Surface of metal powder (surface of powder bed)
3 Molded object 5 Work table (powder holding unit)
7 Powder supply unit (powder supply unit)
8. Electron beam irradiation device (energy applying unit)
10 Molding tank (powder holding part)
11 Raw material tank (powder supply section)
11a Discharge port (supply port of powder supply section)
14 Molding tank moving mechanism (holding part moving mechanism)
15 First preheater 16 Second preheater 31 Controller (control unit)
A Powder bed D Irradiation area (energy application area)
XX direction (direction along the surface of the powder bed, moving direction)
Y Y direction Z Z direction

Claims (12)

A powder holding unit capable of holding a powder bed containing powder,
An energy applying unit that applies energy to the powder held by the powder holding unit;
A holder moving mechanism that moves the powder holder in a direction along the surface of the powder bed,
In the moving direction of the powder holding unit, a preheater disposed on at least one of the front side and the rear side of the energy applying unit, and disposed to cover the powder bed,
A controller configured to control the movement of the powder holding unit using the holding unit moving mechanism to control a preheating time by the preheating heater.   2. The additive manufacturing apparatus according to claim 1, wherein the control unit controls a stop time at a position related to the preheater, the stop time being a time during which the powder holding unit is stopped. 3.   3. The additive manufacturing apparatus according to claim 1, wherein the control unit controls a moving speed of the powder holding unit during preheating by the preheating heater. 4. In the moving direction, a powder supply unit that is disposed on a front side of the energy applying unit and supplies the powder to the powder holding unit,
The additive manufacturing apparatus according to any one of claims 1 to 3, wherein the preheater is disposed forward of the powder supply unit in the moving direction.   5. The additive manufacturing apparatus according to claim 4, wherein, in the moving direction, the powder supply unit is disposed adjacent to the energy applying unit, and the preheater is disposed adjacent to the powder supply unit. 6.   The additive manufacturing apparatus according to any one of claims 1 to 5, wherein the preheater includes a first preheater and a second preheater arranged on both sides of the energy applying unit in the moving direction.   The preheater is disposed so as to cover the entire area of the surface of the powder bed in the moving direction, except for an energy application region by the energy application unit and a region below a supply port of the powder supply unit. An additive manufacturing apparatus according to any one of claims 1 to 6. A preheating step of preheating a powder bed containing the powder,
An energy applying step of applying energy to the powder preheated in the preheating step while moving the powder bed in a direction along a surface of the powder bed,
In the preheating step, a method of manufacturing a layered object, wherein a movement of the powder bed is controlled to control a preheating time.   9. The method for manufacturing a layered object according to claim 8, wherein in the preheating step, at a position related to a preheater, a stop time that is a time during which the powder bed is stopped is controlled.   The method for manufacturing a layered object according to claim 8, wherein in the preheating step, a moving speed of the powder bed is controlled. A first energy applying step which is the energy applying step of applying energy to the powder while moving the powder bed in a first direction;
A first powder supply step of supplying new powder onto the energy-applied powder during the execution of the first energy supply step;
A first preheating step, which is the preheating step of preheating the powder bed containing the powder supplied in the first powder supply step,
A second energy applying step for applying energy to the powder preheated in the first preheating step while moving the powder bed in a second direction opposite to the first direction; Process and
A second powder supply step of supplying a new powder on the energy-applied powder during the execution of the second energy supply step;
A second preheating step, which is the preheating step of preheating the powder bed containing the powder supplied in the second powder supply step, and a method of manufacturing the laminate molded article according to any one of claims 8 to 10. Production method.   In the preheating step, the entire area of the surface of the powder bed is simultaneously preheated in a moving direction of the powder bed, except for an energy applying area in the energy applying step and an area below a supply port of a powder supply unit. The method for producing a layered product according to any one of 8 to 11.

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