JP2020055234A - Lamination molding apparatus - Google Patents

Abstract

To provide a lamination molding apparatus capable of suppressing a heat loss upon manufacturing a molded article.SOLUTION: A lamination molding apparatus 1 includes: a powder holding unit 5 holding a powder bed A containing a powder 2; an energy imparting unit 8 imparting energy to the powder 2; and a reflector 22 reflecting thermal energy emitted from the powder bed A held by the powder holding unit 5 back to the powder bed A.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to an additive manufacturing apparatus.

  There is an additive manufacturing apparatus that manufactures a three-dimensional additive manufacturing object by irradiating, for example, an electron beam to powder as a material to melt the powder (for example, see Patent Document 1).

Japanese Patent No. 6154544

  For example, when the powder is heated to a high temperature by irradiation with an electron beam, the powder is radiated by radiative heat transfer (radiation) in proportion to the difference between the fourth power of the absolute temperature of the powder and the fourth power of the surrounding absolute temperature. The present disclosure describes a layered modeling apparatus that can suppress heat loss when modeling a modeled object.

  The additive manufacturing apparatus according to the present disclosure includes a powder holding unit that holds a powder bed including powder, an energy applying unit that applies energy to the powder, and heat energy radiated from the powder bed held by the powder holding unit. A reflector that reflects off the floor.

  In the additive manufacturing apparatus, heat energy radiated from the powder bed is reflected by the reflector and transferred to the powder bed. Thereby, heat loss from the powder bed can be suppressed.

  The reflector may be arranged outside the irradiation area of the energy beam irradiated from the energy applying unit. This prevents the energy beam irradiation area from being narrowed.

  The reflecting surface of the reflector may include a curved surface. The curved surface may be curved so as to be recessed on the opposite side of the powder bed. Thereby, a curved surface can be formed and the position where heat energy is reflected can be set.

  The additive manufacturing apparatus may include a rear reflector disposed on the opposite side of the reflector from the powder bed and apart from the reflector. Thereby, the heat energy radiated from the reflector to the opposite side to the powder bed can be reflected to the reflector by the rear reflector. A decrease in the temperature of the reflector can be suppressed, and a decrease in heat energy reflected from the reflector to the powder bed can be suppressed.

  The additive manufacturing apparatus may include a recoater that moves in a direction along the surface of the powder bed to level the surface of the powder bed. The reflector may be located above the recoater. Thus, the reflector can be arranged above the range in which the recoater moves.

  The additive manufacturing apparatus may include an auxiliary reflector disposed between the surface of the powder bed and the reflector. The additive manufacturing apparatus may include an auxiliary reflector moving mechanism for displacing the auxiliary reflector with respect to the reflector. Thereby, the heat energy radiated from the powder bed can be reflected on the powder bed by the auxiliary reflector. The additive manufacturing apparatus may change the direction of the auxiliary reflector to change the position where the heat energy is reflected. The additive manufacturing apparatus may secure the range in which the recoater moves by displacing the auxiliary reflector. The additive manufacturing apparatus can displace the auxiliary reflector so as not to hinder the movement of the recoater.

  The layered modeling apparatus of the present disclosure can suppress heat loss at the time of modeling a molded article.

It is sectional drawing which shows the additive manufacturing apparatus which concerns on one Embodiment. It is sectional drawing which expands and shows the inside of the vacuum chamber of an additive manufacturing apparatus. It is a perspective view which shows a thermal energy recovery unit. It is sectional drawing which expands and shows a thermal energy recovery unit. It is a block diagram of an additive manufacturing apparatus. It is a flowchart which shows the procedure of the manufacturing method of a layered object. It is sectional drawing which shows the reflection plate which concerns on a modification.

  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 electron beam irradiation region D of the electron beam irradiation device 8 in the X direction crossing the Z direction. A discharge port is provided at the bottom of the raw material tank 11. The discharge ports are continuous, for example, in the Y direction. The Y direction is a direction that intersects the X direction and the Z direction.

  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 13 for leveling the metal powder 2. The powder application mechanism 13 includes a recoater 13a. The recoater 13 a is movable in the X direction above the work table 5 and the overhang plate 12, scrapes the metal powder 2 deposited on the overhang plate 12 onto the work table 5, and The surface (upper surface) 2a of the uppermost layer of the laminate of the metal powder 2 can be leveled. Hereinafter, the “laminate of the metal powder 2” is referred to as a powder bed A. The recoater 13a can make the height uniform by contacting the surface 2a of the powder bed A. The recoater 13a 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 powder applying mechanism 13 may be configured to include a roller, a bar-shaped member, a brush portion, and the like, instead of the plate-shaped recoater 13a.

  The powder applying mechanism 13 may include, for example, a rack and pinion type driving mechanism as a mechanism for moving the recoater 13a. The powder application mechanism 13 may include a guide rail, an endless belt, a ball screw, an electric motor, a cylinder, and the like.

  The electron beam irradiation device 8 includes an electron gun (not shown) that irradiates an electron beam (electron beam) as an energy beam. In FIG. 1, the irradiation area D through which the emitted electron beam passes is indicated by a two-dot chain line. 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.

  Here, as shown in FIGS. 1 to 4, the modeling apparatus 1 includes a thermal energy recovery unit 20. The thermal energy recovery unit 20 includes a reflector support 21 and a reflector 22. The reflection plate support portion 21 includes a plurality of support plates 23, and has, for example, a cylindrical shape as shown in FIG. The cylindrical portion of the reflection plate support 21 is constituted by a plurality of support plates 23. The plurality of support plates 23 have, for example, a trapezoidal shape, and the oblique sides may be joined. The support plate 23 is arranged to be inclined with respect to the axis L1 extending in the Z direction. The support plate 23 is inclined so as to approach the axis L1 as it goes upward. The support plate 23 is arranged so as to avoid the irradiation area D, as shown in FIG. The support plate 23 is arranged outside the irradiation area D. In other words, the irradiation area D is formed inside the cylindrical portion.

  As the support plate 23, a non-magnetic material such as stainless steel can be used. The support plate 23 is fixed to the vacuum chamber 4. The reflection plate support 21 may include a fixing plate 24, as shown in FIG. An opening 24a penetrating in the thickness direction is provided at the center of the fixing plate 24. The opening 24a is an opening through which an electron beam can pass. The thickness direction of the fixed plate 24 is along the Z direction. The upper ends of the plurality of support plates 23 are joined to the fixed plate 24. The plurality of support plates 23 are arranged so as to extend downward from the fixed plate 24. As shown in FIGS. 1 and 2, the fixing plate 24 can be fixed to, for example, a top plate 4 a of the vacuum chamber 4.

  The reflection plate 22 is a reflector that reflects the heat radiated from the powder bed A to the powder bed A. The reflector 22 is supported by the reflector support 21. The reflection plate 22 is joined to, for example, a lower end of the support plate 23. The thermal energy recovery unit 20 may include a plurality of reflectors 22. The plurality of reflectors 22 include, for example, a pair of reflectors 22 facing in the X direction and a pair of reflectors 22 facing in the Y direction. As the reflection plate 22, a non-magnetic material such as stainless steel can be used.

  The plurality of reflection plates 22 may have a trapezoidal shape, for example, and the oblique sides may be joined. The reflection plate 22 is arranged to be inclined with respect to the axis L1. The reflection plate 22 is inclined so as to approach the axis L1 as it goes upward. The inclination angle of the reflection plate 22 with respect to the XY plane may be, for example, 45 degrees. The reflection plate 22 is arranged so as to avoid the irradiation area D, as shown in FIG. The reflection plate 22 is arranged outside the irradiation area D. The plurality of reflectors 22 are arranged around the powder bed A when viewed from the Z direction.

  The reflection plate 22 is disposed to the outside of the side wall 10a of the modeling tank 10 when viewed from the Z direction. The lower end 22b of the reflector 22 facing the X direction is arranged outside the side wall 10a in the X direction. Similarly, the lower end portion 22b of the reflection plate 22 facing the Y direction is disposed outside the side wall 10a in the Y direction.

  The reflection plate 22 includes a reflection surface 22c. The reflection surface 22c is a surface closer to the surface 2a of the powder bed A. The normal L2 of the reflection surface 22c is arranged, for example, so as to pass through the surface 2a of the powder bed A. The normal L2 is, for example, a virtual straight line passing through the center of the reflection surface 22c and orthogonal to the reflection surface 22c. The normal line L2 extends in the thickness direction of the reflection plate 22. The reflection plate 22 includes a back surface 22d which is a surface opposite to the reflection surface 22c in the thickness direction.

  The thermal energy recovery unit 20 may include a plurality of back side reflectors (back side reflectors) 25, as shown in FIG. In FIG. 1 to FIG. 3, the illustration of the rear-side reflector 25 is omitted. The rear-side reflector 25 is arranged on the opposite side of the powder plate A with respect to the reflector 22. The thickness direction of the back side reflection plate 25 is the same as the thickness direction of the reflection plate 22, and may be the direction in which the normal L2 extends. The rear-side reflector 25 is arranged apart from the reflector 22 in the direction in which the normal line L2 extends. A non-magnetic material such as stainless steel can be used as the back-side reflector 25, for example.

  The rear side reflection plate 25 includes a reflection surface 25a. The reflection surface 25a faces the back surface 22d of the reflection plate 22 in the direction in which the normal line L2 extends. A predetermined gap is formed between the reflection surface 25a and the back surface 22d. The size and shape of the rear-side reflector 25 are, for example, substantially the same as those of the reflector 22. The rear-side reflector 25 may be supported by, for example, the reflector 22. The back side reflection plate 25 may be supported by the support plate 23. The rear side reflection plate 25 may be supported by being connected to, for example, a side plate of the raw material tank 11, or may be supported by another member.

  The reflection plate 22 and the rear-side reflection plate 25 may be arranged above the recoater 13a in the Z direction. The lower end 22b of the reflection plate 22 may be disposed above the upper end of the recoater 13a. Similarly, the lower end of the rear-side reflector 25 may be arranged higher than the upper end of the recoater 13a. Thereby, a region through which the recoater 13a can pass is secured below the reflection plate 22 and the rear-side reflection plate 25. For example, when the recoater 13a moves in the X direction, the reflection plate 22 and the rear-side reflection plate 25 that face each other in the Y direction need not be disposed above the recoater 13a. For example, the lower end 22b of the reflection plate 22 may be arranged to a position below the upper end of the recoater 13a.

  The thermal energy recovery unit 20 may include a plurality of auxiliary reflectors (auxiliary reflectors) 26. As the reflection plate 26, for example, a nonmagnetic material such as stainless steel can be used. The auxiliary reflector 26 is arranged between the surface 2 a of the powder bed A and the reflector 22 in the Z direction. The plurality of auxiliary reflectors 26 are arranged corresponding to the plurality of reflectors 22 in a plan view. The plurality of auxiliary reflectors 26 may include a pair of auxiliary reflectors 26 facing in the X direction and a pair of auxiliary reflectors 26 facing in the Y direction. The plate thickness direction of the pair of auxiliary reflection plates 26 facing in the X direction is along the X direction. The thickness direction of the pair of auxiliary reflection plates 26 facing the Y direction is along the Y direction. The auxiliary reflector 26 is connected to the reflector 22. The auxiliary reflection plate 26 may extend to the vicinity of the overhang plate 12 in the Z direction. The surface of the overhang plate 12 coincides with the surface 2a of the powder bed A in the Z direction.

  The auxiliary reflection plate 26 includes a reflection surface 26a. The reflecting surface 26a is a surface on the powder bed A side, and is a surface capable of reflecting the heat energy radiated from the powder bed A. The reflection surface 26a may be a surface parallel to the axis L1, or may be arranged to be inclined with respect to the axis L1.

  The thermal energy recovery unit 20 may include an auxiliary reflector moving mechanism 27. The auxiliary reflector moving mechanism 27 may include, for example, a hinge, a driving source, a power transmission mechanism, and the like. For example, the upper end of the auxiliary reflector 26 is connected to the lower end 22 b of the reflector 22. The auxiliary reflector 26 is supported by the reflector 22 via a hinge, for example, and is swingable. The drive source is, for example, an electric motor. The power transmission mechanism includes, for example, a gear, a rotating shaft, a belt, and the like. The driving force from the driving source is transmitted to the auxiliary reflection plate 26 via the power transmission mechanism. Thus, the auxiliary reflecting plate 26 can be displaced by swinging. For example, a space through which the recoater 13a can pass can be secured between the auxiliary reflector 26 and the overhang plate 12 by displacing the lower end of the auxiliary reflector 26 upward.

  The controller 31 illustrated in FIG. 5 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, and the auxiliary reflector moving mechanism 27. 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 arithmetic unit 32 may transmit a command signal to the powder coating mechanism 13 to control the operation timing of the recoater 13a.

  Next, a method of manufacturing a layered object will be described. FIG. 6 is a flowchart illustrating a procedure of a method of manufacturing a layered object. First, as a preparation step, the auxiliary reflection plate 26 is displaced (step S1). The controller 31 transmits a command signal to the auxiliary reflector moving mechanism 27 to displace the auxiliary reflector 26. The auxiliary reflector moving mechanism 27 displaces the lower end of the auxiliary reflector 26 upward to form a space through which the recoater 13a can pass.

  Next, the work table 5 is lowered (step S2). The controller 31 sends a command signal to the lifting device 6 to lower the work table 5. The work table 5 is lowered to secure a space for supplying, for example, one layer of the metal powder 2. In addition, the auxiliary reflection plate 26 may be displaced while the work table 5 is lowered, or the auxiliary reflection plate 26 may be displaced after the work table 5 is lowered.

  Next, the metal powder 2 is supplied and leveled (step S3). Here, the metal powder 2 on the overhang plate 12 is scraped onto the work table 5 to supply the metal powder 2 and level the surface 2a of the powder bed A. The controller 31 transmits a command signal to the powder coating mechanism 13 to move the recoater 13a in the X direction. The recoater 13a moves from the outside of the modeling tank 10 in the X direction, and scrapes the metal powder 2 on the overhang plate 12 to the work table 5 side. The recoater 13a supplies the metal powder 2 onto the work table 5 while moving the work table 5 in the X direction above the work table 5 and levels the surface 2a of the powder bed A. Thereby, the surface 2a of the powder bed A can be made flat.

  Next, the auxiliary reflection plate 26 is displaced (step S4). The controller 31 transmits a command signal to the auxiliary reflector moving mechanism 27 to displace the auxiliary reflector 26. The auxiliary reflecting plate moving mechanism 27 displaces the lower end of the auxiliary reflecting plate 26 downward so that the reflecting surface 26a of the auxiliary reflecting plate 26 faces the surface 2a of the powder bed A.

  Next, an electron beam is irradiated (Step S5). 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 on the position where the electron beam is irradiated is stored in the memory 33, for example. The powder bed A may be preheated before the irradiation of the electron beam in step S5. For example, the powder bed A may be preheated using a preheating heater, or the powder bed A may be preheated by irradiating an electron beam. In the method of manufacturing a layered object, the steps S1 to S5 are repeated to complete the object 3.

  In the modeling apparatus 1, when the powder bed A is irradiated with an electron beam, the powder bed A is heated to a high temperature. Thermal energy is radiated from the hot powder bed A. The temperature of the surface 2a of the powder bed A may be, for example, about 1000 ° C. The temperature of the surface 2a of the powder bed A may be another temperature. Since the modeling apparatus 1 includes the reflector 22, the heat energy radiated from the powder bed A is reflected by the reflector 22 and is transferred to the powder bed A. Thereby, the thermal energy radiated from the powder bed A can be recovered, so that the heat loss from the powder bed A can be suppressed. As a result, an increase in energy supplied from the electron beam irradiation device 8 can be suppressed.

  Then, when the temperature of the reflection plate 22 becomes high, heat energy is radiated from the reflection plate 22. Since the modeling device 1 includes the rear-side reflector 25, the heat energy radiated from the rear surface 22 d of the reflector 22 is reflected by the rear-side reflector 25 and transferred to the reflector 22. Thereby, since the heat energy radiated from the back surface 22d of the reflection plate 22 can be recovered, a decrease in the temperature of the reflection plate 22 can be suppressed. As a result, it is possible to suppress a decrease in heat energy reflected from the reflection plate 22 to the powder bed A.

  In addition, since the modeling apparatus 1 includes the auxiliary reflector 26 disposed between the surface 2a of the powder bed A and the reflector 22 in the Z direction, the thermal energy radiated from the powder bed A is auxiliary reflected. It can be reflected off the powder bed A by the plate 26.

  Further, since the modeling apparatus 1 includes the auxiliary reflector moving mechanism 27 for displacing the auxiliary reflector 26 with respect to the reflector 22, the auxiliary reflector 26 is displaced to secure a space in which the recoater 13a moves. be able to. The modeling device 1 can displace the auxiliary reflection plate 26 so as not to hinder the movement of the recoater 13a. The auxiliary reflector moving mechanism 27 may change the direction of the auxiliary reflector 26 to change the position at which the heat energy is reflected.

  Further, in the modeling apparatus 1, since the reflection plate 22 is arranged outside the electron beam irradiation region D, the electron beam irradiation region is prevented from being narrowed. In the modeling apparatus 1, the reflection plate 22 is disposed above the recoater 13a in the Z direction. Thus, a region through which the recoater 13a can pass can be secured below the reflection plate 22.

  Next, a thermal energy recovery unit 28 according to a modification will be described with reference to FIG. The modeling device 1 may include a thermal energy recovery unit 28 including a reflection plate 29. The reflection plate 29 has a reflection surface 29c that is a curved surface. The reflection surface 29c is curved so as to be depressed on the opposite side to the powder bed A. The normal L3 of the reflection surface 29c is arranged, for example, so as to pass through the surface 2a of the powder bed A. The normal L3 is, for example, an imaginary straight line passing through the center between the upper end 29a and the lower end 29b on the reflection surface 29c and orthogonal to the reflection surface 29c.

  The upper end 29a of the reflection plate 29 is continuous with the support plate 23, for example. The support plate 23 is disposed so as to form a conical shape around the axis L1. The reflection plate 29 is continuous around the axis L1, and is annularly arranged outside the support plate 23 in plan view.

  Thus, the reflection surface 29c may be a curved surface. The reflection surface 29c may have, for example, a shape along a parabolic curved surface. By making the reflecting surface 29c a curved surface, the position where the heat energy is reflected can be set. The shaping device including the reflection plate 29 according to such a modified example also has the same operation and effect as the shaping device 1 described above.

  The thermal energy recovery unit 28 according to the modified example may include a back side reflector. The thermal energy recovery unit 28 may include an auxiliary reflector and an auxiliary reflector moving mechanism.

  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 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, and irradiates 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. In this case, the irradiation device that irradiates the laser may include, for example, a mirror that polarizes the laser beam, and a driving unit for moving the mirror and optical components such as a condenser lens.

  In the above-described embodiment, the configuration is provided with the rear-side reflector 25, but the modeling apparatus 1 does not have to include the rear-side reflector 25. Further, the modeling apparatus 1 may include two or more back-side reflectors 25.

1 Molding equipment (Lamination molding equipment)
2 Metal powder 2a Surface of powder bed 5 Work table (powder holder)
8. Electron beam irradiation device (energy applying unit)
13a Recoater 22 Reflector (Reflector)
22c Reflective surface 25 Back side reflector (back side reflector)
26 Auxiliary reflector (auxiliary reflector)
27 Auxiliary reflector moving mechanism (Auxiliary reflector moving mechanism)
29 Reflector (reflector)
29c Reflective surface (curved surface)
A Powder bed D Irradiation area

Claims (7)

A powder holding unit that holds a powder bed containing powder,
An energy applying unit for applying energy to the powder,
A reflector that reflects heat energy radiated from the powder bed held by the powder holding unit to the powder bed.   2. The additive manufacturing apparatus according to claim 1, wherein the reflector is arranged outside an irradiation area of the energy beam emitted from the energy applying unit. 3.   3. The additive manufacturing apparatus according to claim 1, wherein a reflecting surface of the reflector is arranged to be inclined with respect to a normal to a surface of the powder bed. 4. The reflecting surface of the reflector includes a curved surface,
The additive manufacturing apparatus according to any one of claims 1 to 3, wherein the curved surface is curved so as to be depressed on a side opposite to the powder bed.   The additive manufacturing apparatus according to any one of claims 1 to 4, further comprising a back-side reflector disposed on the opposite side of the reflector from the powder bed and apart from the reflector. A recoater that moves in a direction along the surface of the powder bed and leveles the surface of the powder bed,
The additive manufacturing apparatus according to claim 1, wherein the reflector is disposed above the recoater. A surface of the powder bed, an auxiliary reflector disposed between the reflector,
The additive manufacturing apparatus according to any one of claims 1 to 6, further comprising: an auxiliary reflector moving mechanism that displaces the auxiliary reflector with respect to the reflector.

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