JP7408919B2 - Additive manufacturing equipment - Google Patents

Description

The present invention relates to an additive manufacturing apparatus.

2. Description of the Related Art Laminated manufacturing apparatuses are known that manufacture molded objects by solidifying powder, which is a material. For example, Patent Document 1 describes a powder bed containing powder, a modeling table capable of holding a modeled object, a laser beam emitting unit that solidifies the powder held on the modeling table with a laser, and a modeling table that sandwiches the modeling table. A pair of powder supply tables are provided adjacent to the molding table to deposit the powder supplied to the modeling table, and by reciprocating between the pair of powder supply tables, the powder deposited on each of the powder supply tables is modeled. An additive manufacturing apparatus is disclosed that includes a recoater that scrapes onto a table.

In the additive manufacturing apparatus of Patent Document 1, the recoater includes a scraper that scrapes powder and a holder that supports the scraper and moves back and forth between a pair of powder supply tables. The holder includes a first support plate attached horizontally to the upper end of the scraper, a second support plate attached vertically to the end of the first support plate, and a horizontal support plate attached to the lower end of the second support plate. and an attached sensing plate.

Japanese Patent Application Publication No. 2007-307742

By the way, in the above-mentioned additive manufacturing apparatus, when the scraper scrapes up the powder with poor fluidity, the powder may come into contact with the holder, and the powder may be compacted by the lower surface of the holder. When the powder is compacted by the holder, the powder will not fall off from the holder while the scraper is scraping the powder in that direction, and when the scraper is scraping the powder in the opposite direction, the scraper will not fall off in that direction. When the powder is scraped together, the compacted lumps of powder may fall off from the holder. When such solidified lumpy powder flakes off on the modeling table, the powdery lump is solidified by the laser, which may adversely affect the operation of the recoater and the quality of the printing.

Therefore, an object of the present invention is to provide a layered manufacturing apparatus in which compaction of powder by a holder is reduced.

The present invention provides a powder holding section that can hold a powder bed containing powder and a shaped object, a powder solidifying section that solidifies the powder held in the powder holding section, and a powder holding section that is adjacent to the powder holding section so as to sandwich the powder holding section. A pair of powder depositing parts are provided to deposit the powder supplied to the powder holding part, and by reciprocating between the pair of powder depositing parts, the powder deposited in each of the powder depositing parts can be transferred to The recoater includes a scraper that scrapes up powder, and a holder that reciprocates between a pair of powder accumulation sections while removably supporting the scraper. The holder includes a first scraping surface facing the recoater and a second scraping surface facing the recoater return direction, and the holder includes a first side surface facing the recoater forward travel direction and a second side surface facing the recoater return travel direction. The laminated manufacturing apparatus includes: the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface decrease as the vertical direction increases.

According to this configuration, the powder holding part that can hold the powder bed containing powder and the shaped object, the powder solidifying part that solidifies the powder held in the powder holding part, and the powder holding part that sandwich the powder holding part. A pair of powder depositing parts are provided adjacent to each other and deposit powder supplied to the powder holding part. In an additive manufacturing apparatus equipped with a recoater that scrapes powder onto a holding part, the recoater has a scraper that scrapes powder and a holder that reciprocates between a pair of powder accumulation parts while removably supporting the scraper. The holder includes a first scraping surface facing in the forward direction of the recoater and a second scraping surface facing in the backward direction of the recoater, and the holder includes a first side surface facing in the forward direction of the recoater and a second scraping surface facing in the backward direction of the recoater. The distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface decrease in the vertical direction, and the scraper scrapes the powder. Even if the powder comes into contact with the first and second side surfaces of the holder, there is a space for the powder to flow diagonally above the first and second side surfaces, so the powder will not be compacted by the holder. Reduced.

In this case, it is preferable that the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface decrease continuously in the vertical direction.

According to this configuration, since the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface continuously decrease in the vertical direction, when the scraper scrapes the powder Even if the powder comes into contact with the first and second side surfaces of the holder, there is always a space for the powder to flow diagonally above the first and second sides, so the powder will not be compacted by the holder. further reduced.

When the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface continuously decrease in the vertical direction, the first side surface and the second side surface become smaller in the vertical direction. It may be a curved surface that reduces the rate of decrease in the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface.

According to this configuration, in the first side surface and the second side surface, the decreasing rate of the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface decreases as the vertical direction increases. Because of the curved surface, even if the powder comes into contact with the first and second side surfaces of the holder when the scraper scrapes up the powder, the powder will not leave the holder above the first and second sides, which are at an angle close to horizontal. It becomes easy to peel off. Therefore, for example, when the scraper scrapes powder in the backward direction, it is possible to reduce the possibility that the compacted powder will peel off from the holder when the scraper scrapes the powder in the forward direction.

Further, when the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface continuously decrease as the vertical direction increases, the distance between the first side surface and the second side surface decreases as the distance increases in the vertical direction. The curved surface may be a curved surface in which the decreasing rate of the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface increases.

According to this configuration, in the first side surface and the second side surface, the decreasing rate of the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface increases as the vertical direction increases. Because of the curved surface, even if the powder comes into contact with the first and second side surfaces of the holder when the scraper scrapes the powder, the powder is likely to fall off from the outwardly swollen first and second side surfaces. Therefore, for example, when the scraper scrapes powder in the backward direction, it is possible to reduce the possibility that the compacted powder will peel off from the holder when the scraper scrapes the powder in the forward direction.

Further, the first side surface does not touch the plane forming the angle of repose of the powder upward from the horizontal at the lower end of the first scraping surface, and the second side surface does not touch the plane that forms the angle of repose of the powder upward from the horizontal at the lower end of the second scraping surface. Preferably, it does not touch the plane that forms the angle of repose of the powder.

According to this configuration, the first side surface does not touch the plane forming the angle of repose of the powder upward from the horizontal at the lower end of the first scraping surface, and the second side surface does not touch the plane forming the repose angle of the powder upward from the horizontal at the lower end of the second scraping surface. It does not touch the plane that forms the angle of repose of the powder upward from the horizontal. Therefore, even if the powder comes into contact with the first and second side surfaces of the holder when the scraper scrapes up the powder, for example, when the holder stops at the powder accumulation area at the end of the forward and backward directions, it will not be horizontal. Powder that flows until it forms an angle of repose is likely to fall off from the holder. Therefore, for example, when the scraper scrapes powder in the backward direction, it is possible to reduce the possibility that the compacted powder will peel off from the holder when the scraper scrapes the powder in the forward direction.

According to the additive manufacturing apparatus of the present invention, compaction of powder by the holder is reduced.

FIG. 1 is a longitudinal cross-sectional view showing the layered manufacturing apparatus according to the first embodiment. FIG. 2 is a longitudinal cross-sectional view showing the function of the holder of the recoater of FIG. 1; (A), (B), and (C) are vertical cross-sectional views showing the operation of a conventional recoater. (A) is a longitudinal sectional view showing the action of the holder of the recoater according to the second embodiment, (B) is a longitudinal sectional view showing the action of the holder of the recoater according to the third embodiment, and (C) is a longitudinal sectional view showing the action of the holder of the recoater according to the third embodiment. FIG. 7 is a longitudinal cross-sectional view showing the action of the holder of the recoater according to the fourth embodiment.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In each figure, the same parts or equivalent parts are given the same reference numerals, and redundant explanations will be omitted.

The additive manufacturing apparatus 1 according to the first embodiment shown in FIG. Can be sintered or melted. The additive manufacturing apparatus 1 can manufacture the three-dimensional object 3 by repeating this process.

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

The additive manufacturing apparatus 1 includes a vacuum chamber 4 , a powder holding section 5 , a lifting mechanism 6 , a powder supply section 7 , and a powder solidification section 8 . The vacuum chamber 4 is a container whose interior can be kept in a vacuum (low pressure) state, and a vacuum pump (not shown) is connected thereto. The inside of the vacuum chamber 4 is filled with, for example, argon gas. The powder holding section 5 is capable of holding the powder bed A containing the powder 2 and the shaped object 3. Powder bed A is a stack of powders 2. The powder holding section 5 is, for example, a plate-shaped work table on which the powder 2, which is the material for the shaped object 3, is placed. The powder 2 on the powder holding part 5 is arranged, for example, in layers in multiple stages. The powder holding section 5 has, for example, a rectangular shape in plan view. The shape of the powder holding part 5 is not limited to a rectangle, but may be circular or other shapes.

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

The elevating mechanism 6 is capable of elevating the powder 2 on the powder holding section 5 and the object 3 that is being manufactured. The elevating mechanism 6 includes, for example, a rack and pinion drive mechanism, and moves the powder holding section 5 in the Z direction. The elevating mechanism 6 may include a rod-shaped vertical member 6a connected to the bottom surface of the powder holding section 5 and extending downward, and a drive source 6b for driving the vertical member 6a. For example, an electric motor can be used as the drive source 6b. 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 the side surface of the vertical member 6a. The electric motor is driven, the pinion rotates, power is transmitted, and 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 powder holding part 5 in the Z direction is determined, and this position is maintained. The elevating mechanism 6 is not limited to a rack-and-pinion drive mechanism, and may include other drive mechanisms such as a ball screw or a cylinder.

The powder supply section 7 may include a raw material tank 11 that is a storage section that stores the powder 2 that is the raw material. Raw material tank 11 is placed inside vacuum chamber 4 . The raw material tanks 11 are arranged on both sides of the powder holding section 5, for example, in the X direction intersecting the Z direction. In other words, the raw material tank 11 is arranged on both sides of the modeling tank 10 in the X direction. The powder supply section 7 includes a recoater 9 for leveling the powder 2. A description of the recoater 9 will be given later.

The powder supply section 7 includes a pair of powder deposition sections 12 and a lifting mechanism 13. The pair of powder depositing parts 12 are provided adjacent to the powder holding part 5 so as to sandwich the powder holding part 5 in the X direction, and deposit the powder 2 supplied to the powder holding part 5. The powder depositing section 12 is a powder supply table that deposits the powder 2 supplied to the powder holding section 5. The powder accumulation section 12 is provided adjacent to the powder holding section 5 with the side wall 10a in between in the X direction. The powder deposition section 12 has, for example, a rectangular shape in plan view. The shape of the powder holding part 5 is not limited to a rectangle, but may be circular or other shapes.

The powder deposition section 12 is arranged within the raw material tank 11 within the vacuum chamber 4 . Inside the raw material tank 11, the powder depositing section 12 is movable in the Z direction (vertical direction), and rises sequentially as the powder 2 is supplied. The side wall 11a of the raw material tank 11 guides the movement of the powder deposition section 12. The side wall 11a has a rectangular cylindrical shape (cylindrical shape when the powder holding part 5 is circular) so as to correspond to the outer shape of the powder depositing part 12. The powder accumulation section 12 may constitute the bottom of the raw material tank 11. The side wall 11a of the raw material tank 11 on the powder holding section 5 side may be the same side wall as the side wall 10a of the modeling tank 10.

The elevating mechanism 13 is capable of elevating the powder depositing section 12 and the powder 2 deposited thereon. The elevating mechanism 13 includes, for example, a rack-and-pinion drive mechanism, and moves the powder depositing section 12 in the Z direction. The elevating mechanism 13 includes a vertical member 13a and a drive source 13b, and can have the same configuration as the elevating mechanism 6. A description of the elevating mechanism 13 will be omitted. The elevating mechanism 13 may have a different configuration from the elevating mechanism 6. The elevating mechanism 13 is not limited to a rack-and-pinion drive mechanism, and may include other drive mechanisms such as a ball screw or a cylinder.

The powder solidification unit 8 is a laser irradiation device that melts and solidifies the powder 2 held in the powder holding unit 5. The laser beam emitted from the powder solidification section 8 is irradiated into the vacuum chamber 4 to heat the powder 2. The powder solidification unit 8 can apply energy to the powder 2 to heat and melt the powder 2. The powder solidification section 8 is an energy imparting section that imparts energy to the powder bed A. The powder solidification unit 8 may include optical components such as a mirror that polarizes the laser beam, a drive source that moves the mirror, and a condensing lens that focuses the laser beam.

The additive manufacturing apparatus 1 may include a powder solidification section 8 that is an electron beam irradiation device instead of the powder solidification section 8 that is a laser irradiation device. The electron beam irradiation device may include an electron gun that irradiates an electron beam (electron beam) as an energy beam. The electron beam emitted from the electron gun is irradiated into the vacuum chamber 4 to heat the powder 2. The electron beam irradiation device can apply energy to the powder 2, heat the powder 2, and melt or sinter the powder 2. The electron beam irradiation device is an energy application unit that applies energy to the powder bed A. The electron beam irradiation device may include a coil section that controls electron beam irradiation. The coil section can include, for example, an aberration coil, a focus coil, and a deflection coil.

The recoater 9 reciprocates between the pair of powder depositing parts 12 to scrape up the powder 2 deposited in each of the powder depositing parts 12 toward the powder holding part 5. The recoater 9 includes a scraper 20 that scrapes up the powder 2, and a holder 21A that reciprocates between the pair of powder depositing sections 12 while detachably supporting the scraper 20. The scraper 20 is disposed above the powder holder 5 in the vacuum chamber 4 and can level the surface 2a of the top layer of the powder bed A placed on the powder holder 5.

The scraper 20 is movable together with the holder 21A in the direction opposite to the X direction, that is, the forward direction D2, and in the X direction, that is, the backward direction D3, and smoothes the surface 2a of the powder bed A. The scraper 20 has, for example, a plate shape extending in the Y direction. The scraper 20 may be made of metal or resin, for example. The scraper 20 has a predetermined length in the Y direction. For example, the length of the scraper 20 in the Y direction may match the length of the powder holding section 5 in the Y direction.

The holder 21A is reciprocated between the pair of powder depositing sections 12 by a recoater moving mechanism (not shown). The recoater moving mechanism can drive the electric motor to move the holder 21A to a predetermined position in the X-axis direction and then stop it. As shown in FIG. 1, the recoater 9 can move to the outside of the raw material tank 11, for example, in the forward direction D2 and the backward direction D3. The recoater 9 can reciprocate above the powder holding section 5 and the powder depositing section 12 in the outward direction D2 and the backward direction D3. The recoater 9 can move in the outward direction D2 and the backward direction D3 to scrape up the powder 2 on the powder accumulation section 12 and supply it onto the powder holding section 5. The recoater 9 can supply the powder 2 onto the powder holding section 5 and level the surface 2a of the powder bed A while moving in the outward direction D2 and the backward direction D3.

The additive manufacturing apparatus 1 may include a powder recovery section 19 that can recover excess powder 2. The powder collection unit 19 may include a container that can accommodate the powder 2, for example. The powder recovery section 19 may be disposed outside the raw material tank 11, for example, in the forward direction D2 and return direction D3 of the recoater 9. The outside in the outward direction D2 and the backward direction D3 of the recoater 9 is defined as, for example, with the powder holding section 5 at the center, the side near the powder holding section 5 is the inside, and the side far from the powder holding section 5 is the outside. The powder recovery section 19 may be a space between the side wall 11a of the raw material tank 11 and the side wall of the vacuum chamber 4, for example in the X direction. The powder collecting section 19 may be a bucket capable of storing the powder 2.

As shown in FIG. 2, the scraper 20 includes a first scraping surface 20m facing the outward direction D2 of the recoater 9 and a second scraping surface 20n facing the backward direction D3 of the recoater 9. The holder 21A includes a first side surface 21m facing the forward direction D2 of the recoater 9 and a second side surface 21n facing the backward direction D3 of the recoater 9. The first side surface 21m and the second side surface 21n are flat. The distance d1 between the first scraping surface 20m and the first side surface 21m and the distance d2 between the second scraping surface 20n and the second side surface 21n decrease continuously in the vertical direction D1. The distance d1 between the first scraping surface 20m and the first side surface 21m is, for example, the length of a perpendicular line drawn from an arbitrary position in the vertical direction D1 of the first side surface 21m to a plane including the first scraping surface 20m. means. The distance d2 between the second scraping surface 20n and the second side surface 21n is, for example, the length of a perpendicular line drawn from an arbitrary position in the vertical direction D1 of the second side surface 21n to a plane including the second scraping surface 20n. means.

The first side surface 21m of the holder 21A does not touch the plane P that forms the angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m. Similarly, the second side surface 21n of the holder 21A does not touch the plane P that forms the angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the second scraping surface 20n. The angle of repose θr means the maximum angle of the slope that maintains stability without spontaneously collapsing when the powder 2 is piled up.

In such an additive manufacturing apparatus 1, the powder holding section 5 is lowered to secure a space in which, for example, one layer of powder 2 is supplied. The recoater 9 scrapes the powder 2 on one of the powder depositing sections 12 onto the powder holding section 5, supplies the powder 2, and smoothes the surface 2a of the powder bed A. The powder solidification unit 8 irradiates the powder bed A with a laser beam. The portion of the powder 2 irradiated with the laser beam is melted. The molten powder 2 hardens and becomes part of the shaped object 3. The above steps are then repeated until the object 3 is completed. For example, after the recoater 9 is moved in the forward direction D2, the recoater 9 is moved in the backward direction D3, and the same process is repeated. All layers of the object 3 are formed, and the object 3 is completely formed.

As shown in FIG. 3(A), the holder 22 of the conventional recoater 9 includes a first side surface 22m and a second side surface 22n that are vertical, and can be attached to the first scraping surface 20m and the first scraping surface 20m at any position in the vertical direction. The distance d1 from the first side surface 22m and the distance d2 between the second scraping surface 20n and the second side surface 22n are constant. Therefore, when the scraper 20 scrapes up the powder 2 with poor fluidity, the powder 2 comes into contact with the holder 22, and the powder 2 is compacted by the lower surface of the holder 22. When the powder 2 is compacted by the holder 22, the powder 2 does not come off from the holder 22 while the scraper 20 is scraping the powder 2 in one direction of the forward direction D2.

In the holder 22, the first side surface 22m contacts a plane P forming an angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m. Similarly, the second side surface 22n contacts a plane P forming an angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the second scraping surface 20n. Therefore, even if the powder 2 comes into contact with the first side surface 22m and the second side surface 22n of the holder 22 when the scraper 20 scrapes up the powder 2, for example, the powder accumulation section 12 at the end of the forward direction D2 and the backward direction D3 Even if the powder 2 flows until it forms an angle of repose θr with the horizontal when the holder 22 stops, the powder 2 is difficult to peel off from the holder 22.

On the other hand, as shown in FIG. 3(B), for example, when the scraper 20 scrapes up the powder 2 in the backward direction D3, when the scraper 20 scrapes up the powder 2 in the forward direction D2, a compacted lump is formed. Powder 2 flakes off from holder 22. When such solidified lumpy powder flakes off on the modeling table, as shown in FIG. 3(C), the lumpy powder 2 is solidified by the laser, which may adversely affect the operation of the recoater 9 and the printing quality. be.

On the other hand, in the present embodiment, a powder bed A containing powder 2 and a powder holding section 5 that can hold a shaped object 3, a powder solidifying section 8 that solidifies the powder 2 held in the powder holding section 5, and a powder holding section By reciprocating between a pair of powder depositing parts 12, which are provided adjacent to the powder holding part 5 so as to sandwich the powder 2 therebetween, and depositing the powder 2 supplied to the powder holding part 5, , a recoater 9 that scrapes the powder 2 deposited in each of the powder depositing parts 12 to the powder holding part 5, the recoater 9 includes a scraper 20 that scrapes the powder 2, The scraper 20 has a first scraping surface 20m facing the forward direction D2 of the recoater 9 and a first scraping surface 20m facing the forward direction D2 of the recoater 9, and a holder 21A that reciprocates between the pair of powder depositing sections 12 while being supported in a detachable manner. The holder 21A includes a second scraping surface 20n facing D3, a first side surface 21m facing the forward direction D2 of the recoater 9, and a second side surface 21n facing the backward direction D3 of the recoater 9, In the vertical direction D1, the distance d1 between the first scraping surface 20m and the first side surface 21m and the distance d2 between the second scraping surface 20n and the second side surface 21n decrease, and when the scraper 20 scrapes the powder 2, Even if the powder 2 comes into contact with the first side surface 21m and the second side surface 21n of the holder 21A, a space is secured for the powder 2 to flow obliquely above the first side surface 21m and the second side surface 21n, so that the powder 2 is removed by the holder 21A. 2 is reduced from being compacted.

Furthermore, in the present embodiment, the distance d1 between the first scraping surface 20m and the first side surface 21m and the distance d2 between the second scraping surface 20n and the second side surface 21n continuously decrease as the vertical direction D1 increases. Even if the powder 2 comes into contact with the first side surface 21m and the second side surface 21n of the holder 21A when the scraper 20 scrapes the powder 2, the powder 2 flows diagonally above the first side surface 21m and the second side surface 21n. Since the space is always secured, the powder 2 is further reduced from being compacted by the holder 21A.

Further, in this embodiment, the first side surface 21m does not touch the plane P that forms the repose angle θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m, and the second side surface 21n The lower end 20b of the second scraping surface 20n does not touch the plane P that forms the angle of repose θr of the powder 2 upward from the horizontal. Therefore, even if the powder 2 comes into contact with the first side surface 21m and the second side surface 21n of the holder 21A when the scraper 20 scrapes up the powder 2, for example, the powder accumulation portion 12 at the end of the forward direction D2 and the backward direction D3 When the holder 21A stops at this point, the powder 2 that flows until it forms an angle of repose θr with the horizontal becomes likely to fall off from the holder 21A. Therefore, for example, when the scraper 20 scrapes up the powder 2 in the return direction D3, and when the scraper 20 scrapes up the powder 2 in the forward direction D2, the compacted powder 2 is prevented from peeling off from the holder 21A. .

Other embodiments will be described below. For example, as shown in FIG. 4A, in the holder 21B according to the second embodiment, the distance d1 between the first scraping surface 20m and the first side surface 21m and the second scraping surface 20n increase as the vertical direction D1 increases. The distance d2 between the first side surface 20m and the second side surface 21n decreases continuously, and the distance d2 between the first side surface 20m and the first side surface 21m decreases as the distance d2 between the first side surface 20m and the first side surface 21m increases in the vertical direction D1. This is a curved surface that reduces the rate of decrease in the distance d2 between the scraping surface 20n and the second side surface 21n. The first side surface 21m does not touch the plane P forming the angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m, and the second side surface 21n does not touch the lower end of the second scraping surface 20n. The portion 20b does not touch the plane P forming the angle of repose θr of the powder 2 upward from the horizontal.

In the present embodiment, the first side surface 21m and the second side surface 21n are arranged such that the distance d1 between the first scraping surface 20m and the first side surface 21m and the distance between the second scraping surface 20n and the second side surface 21n are approximately the same in the vertical direction D1. Since the curved surface reduces the rate of decrease in the distance d1, even if the powder 2 contacts the first side surface 21m and second side surface 21n of the holder 21B when the scraper 20 scrapes the powder 2, the angle will be close to horizontal. The powder 2 tends to peel off from the holder 21B above the first side surface 21m and the second side surface 21n. Therefore, for example, when the scraper 20 scrapes the powder 2 in the return direction D3, and when the scraper 20 scrapes the powder 2 in the outward direction D2, the compacted powder 2 is prevented from peeling off from the holder 21B. .

For example, as shown in FIG. 4(B), in the holder 21C according to the third embodiment, the distance d1 between the first scraping surface 20m and the first side surface 21m and the second scraping surface increase as the vertical direction D1 increases. The distance d2 between the surface 20n and the second side surface 21n decreases continuously, and the distance d1 and the distance between the first side surface 20m and the first side surface 21m decrease in the vertical direction D1. This is a curved surface in which the rate of decrease in the distance d2 between the second scraping surface 20n and the second side surface 21n increases. The first side surface 21m does not touch the plane P forming the angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m, and the second side surface 21n does not touch the lower end of the second scraping surface 20n. The portion 20b does not touch the plane P forming the angle of repose θr of the powder 2 upward from the horizontal.

In the present embodiment, the first side surface 21m and the second side surface 21n are arranged such that the distance d1 between the first scraping surface 20m and the first side surface 21m and the distance between the second scraping surface 20n and the second side surface 21n are approximately the same in the vertical direction D1. Since the curved surface increases the rate of decrease in the distance d2, even if the powder 2 comes into contact with the first side surface 21m and second side surface 21n of the holder 21C when the scraper 20 scrapes the powder 2, the outwardly swollen first The powder 2 is likely to peel off from the side surface 21m and the second side surface 21n. Therefore, for example, when the scraper 20 scrapes the powder 2 in the return direction D3, and when the scraper 20 scrapes the powder 2 in the forward direction D2, the compacted powder 2 is prevented from peeling off from the holder 21C. .

For example, like the holder 21D according to the fourth embodiment shown in FIG. 4(C), the distance d1 between the first scraping surface 20m and the first side surface 21m and the second scraping surface The distance d2 between 20n and the second side surface 21n may be decreased in stages. In the holder 21D of this embodiment, the first side surface 21m does not touch the plane P that forms the angle of repose θr of the powder 2 upward from the horizontal at the lower end 20b of the first scraping surface 20m, and the second side surface 21n The lower end 20b of the second scraping surface 20n does not touch the plane P that forms the angle of repose θr of the powder 2 upward from the horizontal.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments.

1 Additive manufacturing apparatus 2 Powder 2a Surface 3 Modeled object 4 Vacuum chamber 5 Powder holding section 6 Elevating mechanism 6a Vertical member 6b Drive source 7 Powder supply section 8 Powder solidification section 9 Recoater 10 Modeling tank 10a Side wall 11 Raw material tank 11a Side wall 12 Powder Deposition section 13 Lifting mechanism 13a Vertical member 13b Drive source 19 Powder collection section 20 Scraper 20m First scraping surface 20n Second scraping surface 20b Lower end portions 21A, 21B, 21C, 21D Holder 21m First side surface 21n Second side surface 22 Holder 22m First side 22n Second side A Powder bed D1 Vertical direction D2 Outward direction D3 Return direction d1 Distance d2 Distance θr Angle of repose P Plane

Claims (5)

a powder holder capable of holding a powder bed containing powder and a shaped object;
a powder solidifying section that solidifies the powder held in the powder holding section;
a pair of powder depositing parts that are provided adjacent to the powder holding part so as to sandwich the powder holding part, and depositing the powder supplied to the powder holding part;
a recoater that scrapes the powder deposited in each of the powder depositing parts to the powder holding part by reciprocating between the pair of powder depositing parts;
Equipped with
The recoater is
a scraper that scrapes up the powder;
a holder that reciprocates between the pair of powder depositing sections while removably supporting the scraper;
has
The scraper includes a first scraping surface facing the forward direction of the recoater and a second scraping surface facing the backward direction of the recoater,
The holder includes a first side surface facing the forward direction of the recoater and a second side surface facing the backward direction of the recoater,
The distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface decrease toward the lower side in the vertical direction,
A space in which the powder flows is formed in the stretching direction of the first side surface and the second side surface on the vertically upper side ,
The first side surface and the second side surface are formed symmetrically with respect to the scraper . Laminated manufacturing according to claim 1, wherein the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface continuously decrease toward the lower side in the vertical direction. Device. The first side surface and the second side surface have a decreasing rate of the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface as they move downward in the vertical direction. The additive manufacturing apparatus according to claim 2, which has a curved surface that reduces. The first side surface and the second side surface have a decreasing rate of the distance between the first scraping surface and the first side surface and the distance between the second scraping surface and the second side surface as they move downward in the vertical direction. 3. The additive manufacturing apparatus according to claim 2, which has an increasing curved surface. The first side surface does not touch a plane forming an angle of repose of the powder upward from the horizontal at the lower end of the first scraping surface,
The second side surface does not touch a plane forming an angle of repose of the powder upward from the horizontal at the lower end of the second scraping surface.
The additive manufacturing apparatus according to any one of claims 1 to 4.

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