JP2021042451A - Additional manufacturing apparatus and additional manufacturing method - Google Patents

Abstract

To provide an additional manufacturing apparatus capable of adjusting input energy of a light beam irradiated on material powder in a chamber to a predetermined amount, by controlling irradiation output of the light beam according to a contamination degree of a light beam transmission member due to fume, and an additional manufacturing method.SOLUTION: An additional manufacturing apparatus 1 includes: a chamber 10; a light beam transmission member 12 capable of transmitting a light beam 40a; a powder feeder 30; a light beam irradiation device 40; and a controller 100. The controller 100 includes a storage part 105 for storing data base expressing relationship between a plurality of input factors and a contamination degree of the light beam transmission member 12; a contamination degree estimation part 107 for estimating the contamination degree based on a plurality of the input factors and the data base; and an output controller 108 for adjusting output of the light beam according to estimated contamination degree, in which a plurality of the input factors contains an irradiation condition of the light beam, and an irradiation time of the light beam.SELECTED DRAWING: Figure 1

Description

The present invention relates to an additional manufacturing apparatus and an additional manufacturing method.

In recent years, metal material powder is irradiated with a light beam (laser beam, etc.), and the irradiated material powder is sintered or melted to be solidified and laminated in layers to produce a three-dimensional metal addition product W (additional manufacturing). AM; Additive Manufacturing) is being actively developed (see, for example, Patent Documents 1 and 2).

When the metal addition product W is manufactured by such an addition manufacturing apparatus, the atmosphere is changed from air to, for example, an inert gas so that the metal addition product W is not oxidized by irradiation with a light beam and the quality is not deteriorated. There is a method of irradiating the material powder with a light beam in the replaced chamber. At this time, in the additional manufacturing apparatus shown in Patent Document 1, the light beam is emitted outside the chamber and then transmitted through a transparent light beam transmitting member (for example, glass) forming a part of the wall of the chamber. Irradiate the material powder in the chamber. As a result, the material powder can be irradiated with a light beam while the atmosphere in the chamber is filled with the inert gas, and oxidation of the metal addition product can be satisfactorily prevented.

JP-A-2017-122265 Japanese Unexamined Patent Publication No. 2018-176213

However, in the additional manufacturing apparatus of Patent Document 1, from the material powder melted by irradiating the material powder with a light beam, evaporative metal generally called fume is generated in an amount corresponding to the continuous irradiation time of the light beam. To do. Then, a part of the fume adheres to the lower surface of the light beam transmitting member facing the inside of the chamber. As a result, the transmittance of the light beam in the light beam transmitting member decreases according to the irradiation time of the light beam, and the amount of energy input of the light beam irradiated to the material powder decreases, so that the metal produced is produced. It may affect, for example, the relative density of the additional product.

The present invention has been made to solve the above problems, and adjusts the irradiation output of the light beam according to the degree of contamination of the light beam transmitting member by the fume, and irradiates the material powder in the chamber with the light beam. It is an object of the present invention to provide an additional manufacturing apparatus and an additional manufacturing method capable of adjusting the input energy of the above to a predetermined amount.

(1. Additional manufacturing equipment)
The additional manufacturing apparatus according to the present invention manufactures an additional product by melting the material powder by irradiation with a light beam and then solidifying or sintering the material powder. The additional manufacturing apparatus constitutes a part of a partition wall of the chamber that divides the manufacturing space and the external space of the chamber into a chamber provided with a manufacturing space for manufacturing the additional product, and the light beam. A light beam transmitting member capable of transmitting the light beam, a powder supply device arranged in the manufacturing space and supplying the material powder to a molding position for molding the additional product, and the light beam in the external space of the chamber. The light beam irradiating device that transmits the light beam transmitting member from the light beam to irradiate the material powder supplied to the modeling position, the powder supply control unit that controls the operation of the powder supply device, and the operation of the light beam irradiating device. It is provided with a control device including a light beam irradiation control unit for controlling the above.

The control device further includes a database showing the relationship between the plurality of input elements and the degree of contamination due to the metal vapor generated by the irradiation of the light beam adhering to the surface of the light beam transmitting member, or the plurality of. A storage unit that stores a trained model generated by machine learning using the input element and the degree of contamination as a training data set, and the database or the trained model stored in the plurality of input elements and the storage unit. Based on this, a dirt degree estimation unit that estimates the dirt degree and an output adjustment unit that adjusts the output of the light beam according to the estimated dirt degree are provided. The plurality of input elements are formed by at least the irradiation conditions of the light beam and the start of the first irradiation of the light beam in a state where the surface of the light beam transmitting member is free of dirt. Including irradiation time.

According to this additional manufacturing apparatus, a database showing the relationship between at least the irradiation conditions of the light beam and the irradiation time of the light beam and the degree of contamination of the surface of the light beam transmitting member, which are a plurality of input elements, or the above-mentioned plurality of. Using a trained model generated by machine learning using the input elements and the degree of contamination as the training data set, the degree of contamination of the light beam transmitting member is estimated, and the output of the light beam is adjusted according to the estimated degree of contamination. .. In other words, without actually measuring the amount of input energy that the light beam that is difficult and time-consuming to measure irradiates the surface of the material powder, the light beam that is insufficient according to the amount of input energy that is insufficient based on the dirt on the light beam transmitting member. Increase the output of. As a result, even if the light beam transmitting member becomes dirty, the amount of energy input of the light beam to be applied to the material powder in the chamber is simply adjusted by adjusting the irradiation output of the insufficient light beam according to the estimated degree of dirt. Can be adjusted to a predetermined amount. Therefore, the additional product can be manufactured easily and at low cost.

(2. Addition manufacturing method)
The additional manufacturing method according to the present invention is the additional manufacturing method described above, wherein the material powder supplied to the molding position is melted by irradiation with the light beam and then solidified or sintered to manufacture the additional product. This is an additional manufacturing method using an apparatus. The additional manufacturing method corresponds to the stain degree estimation step of estimating the stain degree based on the plurality of input elements and the database or the trained model stored in the storage unit, and the estimated stain degree. The output adjusting step for adjusting the output of the light beam is provided. The plurality of input elements include at least the irradiation conditions of the light beam and the light starting from the first irradiation of the light beam in a state where the surface of the light beam transmitting member is not adhered with the dirt. Includes beam irradiation time. According to this additional manufacturing method, similarly to the additional manufacturing apparatus described above, even if the light beam transmitting member is contaminated, only the irradiation output of the insufficient light beam is adjusted according to the estimated degree of contamination. The amount of energy input of the light beam irradiated to the material powder in the chamber can be adjusted to a predetermined amount. Therefore, the additional product can be produced with high quality.

It is a schematic diagram of the additional manufacturing apparatus which concerns on 1st Embodiment. It is a graph explaining the relationship between the degree of contamination in a light beam transmitting member, and the transmittance of a light beam. It is a figure explaining the structure of the light beam irradiation apparatus. It is a figure for demonstrating the input energy of a light beam. It is a block diagram of the control part which concerns on the 1st Embodiment which applied the database to the output adjustment. It is a flowchart of operation of output adjustment which concerns on 1st Embodiment. It is a schematic diagram of the additional manufacturing apparatus which concerns on modification 1. FIG. It is a schematic diagram of the additional manufacturing apparatus which concerns on modification 2. It is a block diagram of the control part which concerns on the modification 3 which applied the trained model generated by the machine learning to the output adjustment.

<1. First Embodiment>
(1-1. Configuration of additional manufacturing apparatus 1)
The configuration of the additional manufacturing apparatus 1 according to the first embodiment will be described with reference to the drawings. The additional manufacturing apparatus 1 performs additional manufacturing by irradiating the metal powder Pm (corresponding to the material powder) spread flat with a light beam 40a (laser beam or the like). In this embodiment, the additional manufacturing apparatus 1 employs an SLM (Selective Laser Melting) method in a powder bed fusion method.

That is, as shown in FIG. 1, the additional manufacturing apparatus 1 irradiates the metal powder Pm arranged layer by layer with the light beam 40a in the manufacturing space PAr described later. As a result, the addition manufacturing apparatus 1 melts the metal powder Pm and then solidifies it to manufacture one layer of the addition product W. After that, the same treatment is repeated for each of the plurality of layers of the metal powder Pm, and the layers are laminated to produce the additional product W.

Here, the light beam 40a includes, for example, a laser beam, and also includes various beams capable of melting the metal powder Pm. Further, various lasers such as a near-infrared wavelength laser, a CO ₂ laser (far infrared laser), and a semiconductor laser can be applied to the laser beam, and the target metal powder Pm (for example, SKD61 (JIS G 4404)) can be applied. ), Aluminum, stainless steel, titanium, maraging steel, etc.).

In this embodiment, SKD61, which is a medium carbon steel and an alloy tool steel, is used as the metal powder Pm. Further, SKD61 is a material equivalent to H13 (AISI / SAE standard). Further, in the present embodiment, the first layer of the metal powder Pm is supplied to the upper surface of the flat base 23 constituting the lowermost layer portion (base portion) of the modeled object.

As shown in FIG. 1, the additional manufacturing device 1 comprehensively operates the chamber 10, the modeled object support device 20, the powder supply device 30, the light beam irradiation device 40, the gas flow generation device 50, and the additional manufacturing device 1. A control device 100 for controlling is provided.

The chamber 10 is formed in a rectangular parallelepiped shape surrounded by partition walls forming each surface. Further, as described above, the chamber 10 is provided with a manufacturing space PAr for manufacturing the additional product W inside each partition wall. That is, each partition wall partitions the manufacturing space PAr in the chamber 10 and the external space OAr outside the chamber 10. Further, the chamber 10 is provided with a transparent light beam transmitting member 12 that forms a part of the partition wall on the upper partition wall.

The light beam transmitting member 12 is, for example, a member that is formed in a disk shape and enables transmission of the light beam 40a. In the present embodiment, the light beam transmitting member 12 is formed of a transparent flat glass. The light beam transmitting member 12 is a member usually referred to as a "protective glass". Although it has been described above that the light beam transmitting member 12 is formed in a disk shape, the light beam transmitting member 12 is not limited to this, and the light beam transmitting member 12 may have any shape.

Further, the light beam transmitting member 12 may be formed of, for example, resin or the like as long as it is transparent. However, it is preferable that the transmittance α of the light beam 40a is higher when the surface of the light beam transmitting member 12 is not contaminated. As shown in the following formula (1), the transmittance α referred to here is the input energy E1 of the light beam 40a before the light beam transmitting member 12 is transmitted and after the light beam transmitting member 12 is transmitted. The ratio of the light beam 40a to the input energy E2 of the light beam 40a at a predetermined position on the surface of the metal powder Pm irradiated by the light beam 40a.

Transmittance α = E2 / E1 ... (1)
E1; Input energy (J) of the light beam 40a before being transmitted by the light beam transmitting member 12.
E2; The input energy (J) of the light beam 40a at the irradiated portion on the surface of the metal powder Pm after being transmitted by the light beam transmitting member 12.
Note that FIG. 2 is a graph showing an outline of the relationship between the “transmittance α” and the “dirt degree D” of the light beam transmitting member 12.

The chamber 10 is configured so that the air inside _{can be replaced with an inert gas such as He (helium), N 2} (nitrogen), Ar (argon), or the like. Any method may be used for the method of substitution with the inert gas. Not limited to the above embodiment, the chamber 10 may be configured so that the inside can be depressurized instead of replacing the air inside with an inert gas.

As shown in FIG. 1, the modeled object support device 20 is composed of a support member for modeling (additional manufacturing) the additional product W, and the upper surface portion for modeling (additional manufacturing) the additional product W is formed. It is provided so as to be exposed in the manufacturing space PAr inside the chamber 10. The modeled object support device 20 includes a modeling container 21, an elevating table 22, and a base 23. The modeling container 21 has an opening that opens into the manufacturing space PAr on the upper side, and has an inner wall surface that is parallel to the vertical axis. The elevating table 22 is provided inside the modeling container 21 so as to be able to move up and down in the vertical direction along the inner wall surface.

The base 23 is detachably placed on the upper surface of the elevating table 22, and the upper surface of the base 23 serves as a support surface for modeling the additional product W. That is, the base 23 can support the additional product W at the time of additional production while arranging the metal powder Pm one layer at a time above the upper surface as the elevating table 22 descends.

The powder supply device 30 is provided adjacent to the modeled object support device 20. The powder supply device 30 includes a powder storage container 31, a supply table 32, and a recorder 33. The powder storage container 31 has an opening that opens into the manufacturing space PAr on the upper side, and the height of the opening of the powder storage container 31 is the same as the height of the opening of the modeling container 21.

The powder storage container 31 has an inner wall surface parallel to the vertical axis. The supply table 32 is provided inside the powder storage container 31 so as to be movable in the vertical direction along the inner wall surface. Then, in the powder storage container 31, the metal powder Pm is stored in the upper region of the supply table 32.

The recorder 33 is provided so as to be reciprocally movable along the upper surfaces of both openings over the entire area of the opening of the modeling container 21 and the opening of the powder storage container 31 in the manufacturing space PAr. The powder storage container 33 is, for example, when moving from the right side to the left side in the left-right direction of FIG. 1, that is, when moving from the opening of the powder storage container 31 toward the opening of the modeling container 21. The metal powder Pm protruding from the opening of 31 is transported to the modeling container 21.

Further, the recorder 33 smoothes the metal powder Pm carried above the lowered base 23 together with the lowered elevating table 22 as described later, and arranges the same type of metal powder Pm in a layer on the upper surface of the base 23. That is, recoat. Here, "the same kind" means that the material of the metal powder Pm, which is the material powder, is the same, and the average particle size and the like of the metal powder Pm are included in a predetermined range.

The light beam irradiator 40 is arranged outside the chamber 10 as shown in FIG. Then, the light beam irradiation device 40 is a light beam transmitting member from the external space OAr of the chamber 10 on the layer surface of the metal powder Pm (material powder) supplied and arranged in a layer shape above the base 23 at the modeling position K. 12 is transmitted and the light beam 40a is irradiated.

As described above, the light beam 40a is a laser beam or the like. The light beam irradiator 40 heats the metal powder Pm to a temperature equal to or higher than the melting point of the metal powder Pm by irradiating the irradiated portion of the recoated metal powder Pm with the light beam 40a. As a result, the metal powder Pm is melted and then solidified (or sintered) to form (manufacture) an additional product W composed of an integrated layer. That is, the adjacent metal powders Pm are integrated by melt joining.

The light beam irradiation device 40 can move the irradiation position of the light beam 40a and change the beam output P according to a preset program under the control of the light beam irradiation control unit 104 included in the control device 100. By moving the irradiation position of the light beam 40a in this way, the additional product W having a three-dimensional shape can be formed.

Further, by changing the beam output P of the light beam 40a, the input energy E2 (the amount of heat input flowing into the irradiated portion) in the irradiated portion of the recoated metal powder Pm changes, and the molten state of the metal powder Pm is changed. Can be changed.

At this time, evaporative metal generally called "fume" is generated from the molten metal in the molten state. The evaporated fume floats in the chamber 10 and adheres as "dirt" to the inner surface of the partition wall of the chamber 10 and the inner surface of the light beam transmitting member 12. In particular, when the fume adheres to the surface of the light beam transmitting member 12 on the manufacturing space PAr side, the transmittance α of the light beam 40a transmitted through the light beam transmitting member 12 decreases. At this time, the degree of decrease in the transmittance α of the light beam 40a is determined according to the “dirt degree D” of the light beam transmitting member 12 due to the fume as described above (see FIG. 2).

Therefore, in the present invention, the light beam transmitting member 12 at a desired time point is based on the correlation between various conditions (input elements) correlated with the "dirt degree D" of the light beam transmitting member 12 and the "dirt degree D". Estimate the "dirt degree D". Then, based on the estimated "dirt degree D", the reduced energy input of the light beam 40a is corrected (adjusted) by increasing the output of the light beam 40a (in the graph of FIG. 2). See dashed line). Details will be described later.

As shown in FIGS. 1 and 3, the light beam irradiation device 40 includes a laser oscillator 41 and a laser head 42. Further, the light beam irradiating device 40 includes an optical fiber 43 that transmits the near-infrared laser light (light beam 40a) oscillated from the laser oscillator 41 to the laser head 42.

The laser oscillator 41 oscillates at an arbitrary beam output P so that the wavelength becomes a predetermined infrared wavelength set in advance, and generates continuous wave near-infrared laser light as the light beam 40a. The laser head 42 is arranged in the chamber 10 at a predetermined distance from the surface of the metal powder Pm arranged in layers. As shown in FIG. 3, the laser head 42 includes an optical system including a collimating lens 42a, a mirror 42b, a galvano scanner 42c, and an fθ lens 42d.

In the laser head 42, the near-infrared laser (light beam 40a) incident on the optical fiber 43 is collimated by the collimating lens 42a and converted into parallel light. As shown in FIG. 3, the collimated near-infrared laser (light beam 40a) is changed in the traveling direction by the mirror 42b so as to be incident on the galvano scanner 42c.

In the laser head 42, the galvano scanner 42c freely changes the traveling direction of the near-infrared laser (light beam 40a), that is, the irradiation angle. As a result, the light beam 40a focused by the fθ lens 42d is irradiated to a predetermined position on the layer surface of the recoated metal powder Pm. That is, the laser head 42 can freely move the light beam 40a in the left-right direction and the direction orthogonal to the left-right direction, in other words, in the horizontal direction including these directions on the layer surface of the recoated metal powder Pm. it can.

The layer surface of the metal powder Pm is a surface that is laminated on the upper surface of the base 23 in a layered manner and is exposed upward in the recoated metal powder Pm. Further, the light beam 40a is made of glass (or resin) and is irradiated to the manufacturing space PAr in the chamber 10 through a transparent light beam transmitting member 12 provided on the upper side of the chamber 10.

As shown in FIG. 1, the gas flow generator 50 is close to the light beam transmitting member 12 between the modeling position K where the light beam 40a is irradiated and the light beam transmitting member 12 in the manufacturing space PAr in the chamber 10. A gas flow F1 of an inert gas (Ar or the like) flowing across the upper space on the side is generated. Further, the gas flow generator 50 generates a gas flow F2 of an inert gas (Ar or the like) that flows across the lower space on the side close to the modeling position K in the manufacturing space PAr in the chamber 10. Details will be described later. In order to generate the gas flows F1 and F2, the gas flow generator 50 includes a gas suction device 51, a tubular first gas discharge nozzle 52, and a tubular second gas discharge nozzle 53.

The gas suction device 51 includes a tubular suction nozzle 51a and a vacuum pump 51b. The suction nozzle 51a is arranged at the lower left of the chamber 10 in FIG. The suction nozzle 51a is arranged so that the suction port 51c is opened in the manufacturing space PAr of the chamber 10. Further, in the suction nozzle 51a, the end opposite to the suction port 51c is connected to the suction port 51b1 of the vacuum pump 51b by a pipe.

The first gas discharge nozzle 52 is arranged at the upper right of the chamber 10 in FIG. At this time, the first gas discharge nozzle 52 is arranged so that the discharge port 52a opens in the manufacturing space PAr of the chamber 10. Further, the end of the first gas discharge nozzle 52 on the opposite side to the discharge port 52a is connected to the discharge port 51b2 of the vacuum pump 51b by a pipe.

The second gas discharge nozzle 53 is arranged at the lower right of the chamber 10 in FIG. The second gas discharge nozzle 53 is arranged so that the discharge port 53a opens in the manufacturing space PAr of the chamber 10. Further, the end of the second gas discharge nozzle 53 opposite to the discharge port 53a is connected to the discharge port 51b2 of the vacuum pump 51b by a pipe.

With the above configuration, when the vacuum pump 51b of the gas suction device 51 operates, the inert gas in the chamber 10 is sucked from the suction nozzle 51a, and the pressure in the chamber 10 decreases. Then, the inert gas sucked from the chamber 10 is discharged from the discharge port 51b2 of the vacuum pump 51b.

The discharge port 51b2 of the vacuum pump 51b is connected to each end of the first gas discharge nozzle 52 and the second gas discharge nozzle 53, respectively. Therefore, the inert gas discharged from the discharge port 51b2 of the vacuum pump 51b is discharged into the production space PAr of the decompressed chamber 10 via the first gas discharge nozzle 52 and the second gas discharge nozzle 53. ..

As a result, the above-mentioned gas flows F1 and F2, which are inert gases, are generated in the production space PAr. By generating the gas flows F1 and F2, when the above-mentioned fume is generated, the flow of the fume can be controlled, and the fume can be suppressed from adhering to the inner surface of the light beam transmitting member 12.

The control device 100 is a microcomputer whose main components are a CPU, a ROM, a RAM, an interface, and the like (not shown). As shown in the block diagrams of FIGS. 1 and 5, the control device 100 includes a data storage unit 101, a powder supply control unit 103, a light beam irradiation control unit 104, an input element acquisition unit 109, a storage unit 105, and a gas flow generation device. It includes a gas flow control unit 106 that controls 50, a pollution degree estimation unit 107, and an output adjustment unit 108. The powder supply control unit 103 includes an elevating table operation control unit 102.

The data storage unit 101 is connected to the light beam irradiation control unit 104. The data storage unit 101 is included in the data for each divided layer obtained by dividing the entire space including the additional product W with a predetermined thickness, and stores various data including the shape data representing the shape of the divided layer. ..

The elevating table operation control unit 102 (a part of the powder supply control unit 103) controls the operation of a drive device (not shown) that elevates and elevates the elevating table 22. When the powder supply device 30 supplies the metal powder Pm, the elevating table operation control unit 102 lowers the elevating table 22 so as to have a preset amount of descent.

The powder supply control unit 103 controls the operation of the powder supply device 30. Specifically, the powder supply control unit 103 moves the supply table 32 in the vertical direction. Then, the metal powder Pm contained in the powder storage container 31 is projected from the opening of the powder storage container 31 by a predetermined amount, and the recorder 33 is controlled to reciprocate. As a result, the layer of the metal powder Pm is supplied to the modeling position K.

The light beam irradiation control unit 104 controls the operation of the light beam irradiation device 40. Specifically, the light beam irradiation control unit 104 determines the irradiation position and beam locus (irradiation locus) of the light beam 40a irradiated by the light beam irradiation device 40 based on the shape data stored in the data storage unit 101. Control.

The input element acquisition unit 109 is connected to the dirt degree estimation unit 107 and each unit in the control device 100. The input element acquisition unit 109 acquires a plurality of current input elements from each unit in the control device 100. The plurality of input elements are generated by, for example, the material of the metal powder Pm (SKD61), various irradiation conditions of the light beam 40a, the irradiation time Tm of the light beam (cumulative irradiation time since the start of contamination), and the gas flow generator 50. These are the flow conditions of the above-mentioned inert gas flows F1 and F2.

The irradiation time Tm of the light beam is acquired from the connected timer. The irradiation time Tm can be defined as the (cumulative) irradiation time of the light beam 40a starting from the first irradiation of the light beam 40a in a state where the surface of the light beam transmitting member 12 is free of dirt. Therefore, the irradiation time Tm is reset when the surface of the light beam transmitting member 12 is cleaned and the surface is free of dirt.

In the storage unit 105 shown in FIGS. 1 and 5, a database DB showing the relationship between the plurality of input elements and the above-mentioned “dirt degree D” is created and stored in advance. As described above, the "dirt degree D" represents the degree of "dirt" generated when the metal vapor (fume) generated by the irradiation of the light beam 40a adheres to the inner surface of the light beam transmitting member 12. It is an index. Further, the plurality of input elements at this time have the same contents as those of the above-mentioned current plurality of input elements, and are the material of the metal powder Pm (SKD61), the irradiation conditions of the light beam 40a, and the irradiation time Tm of the light beam (dirt). Cumulative irradiation time from the beginning), and the flow conditions of the above-mentioned inert gases F1 and F2 generated by the gas flow generator 50.

Further, in the above, the contents of the irradiation conditions of the light beam 40a include the beam output P (not shown), the scanning speed v (see FIG. 4), the scanning interval (scanning pitch) s (not shown), and the modeling position K. The thickness t of the layer of the supplied metal powder Pm can be mentioned (see FIG. 4). ^{Under the above conditions, the energy density E (J / mm 3} ) of the light beam 40a injected into the outermost surface of the layer of the metal powder Pm on the assumption that the surface of the light beam transmitting member 12 is clean is as follows. It is represented by the formula (1). The energy density E corresponds to the input energy according to the present invention.

E = P / (v × s × t) ... (1)
E; Energy density E (J / mm ³ ),
P; beam output (W),
v; scanning speed (mm / s),
s; Scanning interval (scanning pitch) (mm),
t; Layer thickness (mm) of metal powder Pm.

The contents of the flow conditions of the gas flows F1 and F2 include the type of gas (for example, Ar), the flow velocity vf (mm / s), the method of supplying the inert gas, and the like. At this time, as a method of supplying the inert gas in the present embodiment, as shown in FIG. 1, the gas flow F1 is generated so as to cross between the modeling position K and the light beam transmitting member 12 in the horizontal direction. As a result, it is possible to effectively prevent the metal vapor (fume) from rising upward from the molten pool at the modeling position K and directly adhering to the surface of the light beam transmitting member 12.

Further, also in the gas flow F2, a flow from the right to the left in FIG. 1 is generated at a lower position (space) close to the modeling position K in the chamber 10. This also prevents the metal vapor (fume) from rising directly upward from the molten pool at the modeling position K and adhering to the surface of the light beam transmitting member 12.

Then, the material (SKD61) of the metal powder Pm described above, various irradiation conditions of the light beam 40a, the (cumulative) irradiation time Tm of the light beam 40a, and the flows of the gas flows F1 and F2 generated by the gas flow generator 50. The correlation between the conditions and the "dirt degree" of the light beam transmitting member 12 is obtained experimentally to create a database, and the created database (DB) is stored in the storage unit 105.

The dirt degree estimation unit 107 is connected to the input element acquisition unit 109, the storage unit 105, and the output adjustment unit 108. The dirt degree estimation unit 107 estimates the dirt degree based on the current plurality of input elements acquired by the input element acquisition unit 109 and the database stored in the storage unit 105. Then, the output adjusting unit 108 adjusts the output of the light beam 40a of the light beam 40a according to the estimated degree of contamination. That is, the output adjusting unit 108 controls the light beam irradiation control unit 104, and sets the beam output P of the light beam 40a generated by the laser oscillator 41 of the light beam irradiation device 40 as the output value commanded by the output adjusting unit 108.

As a result, as shown by the broken line in FIG. 2, the input energy (E1-E2) of the shortage of the light beam 40a in the irradiated portion of the modeling position K lowered by the “dirt” of the light beam transmitting member 12 is corrected (corrected). ), And when the light beam transmitting member 12 is clean, it can be irradiated with the same magnitude as the input energy E1 to be applied to the modeling position K.

(1-2. Operation)
Next, the output adjustment of the light beam 40a in the addition manufacturing method using the addition manufacturing apparatus 1 will be described with reference to the flowchart shown in FIG. As a premise, the control device 100 of the additional manufacturing device 1 includes a storage unit 105 as described above. Then, as shown in FIG. 5, the storage unit 105 includes a database DB showing the relationship between the above-mentioned plurality of input elements and the “dirt degree”. Further, it is assumed that the surface of the light beam transmitting member 12 is cleaned and is not contaminated when the additional manufacturing apparatus 1 is operated for the first time this time.

Under the above preconditions, the light beam irradiation control unit 104 operates the light beam irradiation device 40 based on the shape data of the additional product W included in the data storage unit 101, and starts the irradiation of the light beam 40a. The light beam irradiation control unit 104 sets the light beam 40a according to irradiation conditions that can be appropriately changed, such as the beam output P of the light beam 40a, the scanning speed v, the scanning interval s, the layer thickness t of the metal powder Pm, and the scanning pattern. Scan. By irradiating the light beam 40a in this way, the metal powder Pm is melted and then solidified.

The program for adjusting the output of the light beam 40a according to the present invention is started at the same time as the light beam 40a is irradiated. In step S10, the timer for measuring the (cumulative) irradiation time Tm of the light beam 40a is reset. At the same time, in step S20, the measurement by the timer is newly started. At this time, when the light beam 40a is irradiated, "dirt" due to the fume begins to gradually adhere to the surface of the light beam transmitting member 12 on the manufacturing space PAr side according to the irradiation time Tm of the light beam 40a.

Then, in step S30, the input element acquisition unit 109 acquires a plurality of input elements and the like in the current operation of the additional manufacturing apparatus 1. Here, the current plurality of input elements are the material of the metal powder Pm (SKD61), the irradiation conditions of the light beam 40a, and the irradiation time Tm of the light beam 40a being measured by the timer (cumulative irradiation after the start of contamination). Time), and the flow conditions of the gas flows F1 and F2 of the above-mentioned inert gas generated by the gas flow generator 50.

Next, in step S40, database data showing the relationship (correlation) between the plurality of input elements and the like acquired in advance based on experiments and the like and the degree of contamination of the light beam transmitting member 12 is acquired from the storage unit 105 ( refer. Then, in step S50 (dirt degree estimation step), the current light beam is based on the current plurality of input elements acquired by the stain degree estimation unit 107 in step S30 and the database DB acquired (referenced) in step S40. The degree of dirtiness of the transparent member 12 is estimated.

Next, in step S60 (output adjusting step), the output adjusting unit 108 adjusts the output of the light beam 40a according to the “dirt degree” estimated in step S50. At this time, the output of the light beam 40a to be adjusted by the output adjusting unit 108 corresponding to the "dirt degree" is also stored in a database in advance based on experiments. Therefore, the output adjusting unit 108 refers to the database, operates the light beam irradiating device 40, adjusts the output of the light beam 40a to the specified output value, and ends the program. As a result, the input energy for the shortage of the light beam 40a at the modeling position K lowered due to the "dirt" of the light beam transmitting member 12 is corrected (corrected), and when the light beam transmitting member 12 is not dirty, the modeling position K is set. It can be irradiated with the same magnitude as the input energy to be irradiated. Therefore, each layer can always be formed with a constant quality (vacancy ratio, relative specific gravity, strength, etc.), and the quality is improved.

In the above flowchart, only one adjustment has been described, but when the irradiation of the light beam 40a is continuously performed, the same processing as described above may be repeated. However, in that case, it goes without saying that a new flowchart may be required to accumulate the irradiation time Tm and apply the accumulated irradiation time Tm as the current input element each time the program ends. No.

Further, in the first embodiment, when producing the additional product W, an embodiment in which the metal powder Pm is melted by irradiation with the light beam 40a and then solidified to be produced has been described. However, the present invention is not limited to this embodiment, and when the additional product W is produced, the metal powder Pm may be sintered by irradiation with the light beam 40a to produce the additional product W. Also in this case, by using the present invention, sintering can always be performed with a predetermined (constant) amount of energy, so that the effect of stabilizing the quality of the additional product W can be obtained as in the above embodiment.

(1-3. Effect of the first embodiment)
According to the first embodiment, the additional manufacturing apparatus 1 is an apparatus for producing the additional manufacturing product W by melting the material powder (metal powder Pm) by irradiation with the light beam 40a and then solidifying or sintering the material powder (metal powder Pm). .. The additional manufacturing apparatus 1 constitutes a part of the partition wall of the chamber that partitions the manufacturing space PAr for manufacturing the additional product W and the external space OAr of the manufacturing space PAr and the light. The light beam transmitting member 12 capable of transmitting the beam 40a, the powder supply device 30 arranged in the manufacturing space PAr and supplying the metal powder Pm to the modeling position K for modeling the additional product W, and the light beam 40a in the chamber. The light beam irradiating device 40 that transmits the light beam transmitting member 12 from the external space OAr of 10 and irradiates the metal powder Pm supplied to the modeling position K, the powder supply control unit 103 that controls the operation of the powder supply device 30, and the powder supply control unit 103. A control device 100 including a light beam irradiation control unit 104 that controls the operation of the light beam irradiation device 40 is provided.

The control device 100 further provides a database DB showing the relationship between the plurality of input elements and the degree of contamination caused by the metal vapor (fume) generated by the irradiation of the light beam 40a adhering to the surface of the light beam transmitting member 12. A dirt degree estimation unit 107 that estimates the degree of contamination based on the storage unit 105 to be stored, a plurality of input elements, and a database stored in the storage unit 105, and the light beam 40a according to the estimated dirt degree. An output adjusting unit 108 for adjusting the output is provided. The plurality of input elements include at least the irradiation conditions of the light beam 40a and the irradiation time of the light beam 40a starting from the first irradiation of the light beam 40a in a state where the surface of the light beam transmitting member 12 is free of dirt. Includes Tm.

According to the additional manufacturing apparatus 1, a database showing the relationship between at least the irradiation conditions of the light beam 40a and the irradiation time Tm of the light beam 40a, which are a plurality of input elements, and the degree of contamination of the surface of the light beam transmitting member 12. The degree of contamination of the light beam transmitting member 12 is estimated using the DB, and the output of the light beam 40a is adjusted according to the estimated degree of contamination. That is, without actually measuring the amount of input energy that the light beam 40a irradiates the surface of the material powder, which is difficult and time-consuming to measure, the shortage of the light beam corresponding to the amount of input energy that is insufficient due to the contamination of the light beam transmitting member The output can be increased. As a result, when the light beam transmitting member 12 becomes dirty, the irradiation output of the insufficient light beam 40a is adjusted easily and at low cost, and the input energy of the light beam irradiated to the material powder in the chamber 10 is increased. It can be modified to always be constant.

Further, according to the first embodiment, the additional manufacturing apparatus 1 generates a gas flow of an inert gas that flows across between the molding position K and the light beam transmitting member 12 in the manufacturing space PAr in the chamber 10. A flow generator 50 is provided. The control device 100 includes a gas flow control unit 106 that controls the gas flow generation device 50, and the plurality of input elements include gas flow conditions of the gas flows F1 and F2 generated by the gas flow generation device 50. By generating the gas flows F1 and F2 as described above, it is possible to satisfactorily suppress the adhesion of the evaporative metal fume to the surface of the light beam transmitting member 12. Further, since the dirt degree estimation unit 107 estimates the dirt degree in consideration of the influences of the gas flows F1 and F2, the dirt degree can be estimated more accurately, and the output of the light beam 40a can be adjusted. It can be done with high accuracy.

Further, according to the first embodiment, the plurality of input elements include the material of the material powder. Also with this, since the degree of contamination can be estimated with higher accuracy, the output of the light beam 40a can be adjusted with higher accuracy.

Further, according to the first embodiment, the output (beam output) of the light beam 40a adjusted by the output adjusting unit 108 is the surface of the material powder supplied to the modeling position K through the light beam transmitting member 12. It is adjusted based on the estimated degree of contamination so that the input energy of the light beam 40a irradiated to the light beam 40a becomes a predetermined amount. In this way, the output is adjusted based on the energy input to the material powder supplied to the modeling position K. Since the amount of energy is one of the most suitable indexes for melting powdered metal, it is possible to manufacture a product with high accuracy by adjusting the output so that the amount of input energy becomes constant.

Further, according to the additional manufacturing method using the additional manufacturing apparatus 1 of the first embodiment, the dirt degree estimation for estimating the dirt degree D based on the plurality of input elements and the database DB stored in the storage unit 105. A step S50 and an output adjusting step S60 for adjusting the output (beam output P) of the light beam 40a according to the estimated degree of contamination D are provided. At this time, the plurality of input elements include at least the light beam 40a starting from the irradiation conditions of the light beam 40a and the initial irradiation of the light beam 40a in a state where the surface of the light beam transmitting member 12 is free of dirt. Irradiation time Tm and.

According to this additional manufacturing method, similarly to the additional manufacturing apparatus 1 described above, even if the light beam transmitting member 12 is contaminated, the beam output P of the insufficient light beam 40a according to the estimated degree of contamination. The input energy of the light beam 40a irradiated to the material powder in the chamber 10 can be adjusted to a predetermined amount simply by adjusting. Therefore, the additional product W can be manufactured with high quality.

Further, in the first embodiment, a database showing the relationship between the plurality of input elements and the degree of contamination D due to the metal vapor (fume) generated by the irradiation of the light beam 40a adhering to the surface of the light beam transmitting member 12. In the DB, the material of the material powder (metal powder Pm) was included as a plurality of input elements. However, the present invention is not limited to this embodiment, and the plurality of input elements may not include the material of the material powder (metal powder Pm). Even with this, a reasonable effect can be expected.

(1-4. Modification example of the embodiment)
(1-4-1. Modification 1)
As a modification 1 of the first embodiment, as shown in FIG. 7, the additional manufacturing apparatus 1 may include a display device 201 that displays the degree of contamination estimated by the contamination degree estimation unit 107. As a result, the operator can always visually confirm the degree of dirt, so that he / she can determine when the dirt needs to be removed and perform the removal work in a planned manner.

(1-4-2. Modification 2)
Further, as a modification 2 of the first embodiment, as shown in FIG. 8, in the additional manufacturing device 1, the storage unit 105 of the control device 100 stores a dirt limit threshold value (not shown) corresponding to the degree of dirt. At the same time, when the degree of dirt estimated by the determination unit 110 by the degree of dirt estimation unit 107 exceeds the limit threshold value, the dirt removal instruction device 301 instructing the user (operator) to remove the dirt on the light beam transmitting member 12. May be provided. As a result, dirt on the surface of the light beam transmitting member 12 can be removed at a constant timing, which is efficient.

(1-4-3. Modification 3)
Further, in the first embodiment, a database DB showing the relationship between the plurality of input elements and the "dirt degree D" is created and stored in the storage unit 105. Then, the dirt degree estimation unit 107 estimates the dirt degree based on the current plurality of input elements and the data of the database DB, and the output adjustment unit 108 outputs the light beam 40a according to the estimated dirt degree. Was adjusted.

However, the present invention is not limited to this embodiment, and as a modification 3, the estimation of the degree of contamination and the adjustment of the beam output P of the light beam 40a are performed on the trained model generated by machine learning as shown in the block diagram of FIG. It may be done based on. That is, in the modification 3, as shown in FIG. 9, the training data set learning unit 210 sets a plurality of input elements acquired and input by the input element acquisition unit 109 and a degree of contamination as teacher data. The acquired training data set is used for machine learning to generate a trained model and store it in the storage unit 105.

The dirt degree estimation unit 107 estimates the dirt degree based on the current plurality of input elements and the learned model stored in the storage unit 105. Then, the output adjusting unit 108 adjusts the output of the light beam according to the estimated degree of contamination, as in the first embodiment. This also has the same effect as that of the first embodiment.

1 additional manufacturing equipment, 10; chamber, 12; light beam transmitting member, 30; powder supply equipment, 40; light beam irradiation equipment, 40a; light beam, 50; gas flow generator, 100; control equipment, 103; powder supply Control unit, 104; Light beam irradiation control unit, 105; Storage unit, 106; Gas flow control unit, 107; Dirt degree estimation unit, 108; Output adjustment unit, 109; Input element acquisition unit, 210; Training data set learning unit , DB; database, F1; gas flow, F2; gas flow, OAr; external space, P; beam output, PAr; manufacturing space, Pm; metal powder (material powder), S50; dirt degree estimation process, S60; output adjustment Step, Tm; irradiation time, v; scanning speed, W; additional product.

Claims (7)

It is an additional manufacturing device that manufactures additional products by melting the material powder by irradiation with a light beam and then solidifying or sintering it.
A chamber provided with a manufacturing space for manufacturing the additional product,
A light beam transmitting member that constitutes a part of the partition wall of the chamber that partitions the manufacturing space and the external space of the chamber and is capable of transmitting the light beam.
A powder supply device that is arranged in the manufacturing space and supplies the material powder to a molding position for molding the additional product.
A light beam irradiating device that irradiates the material powder supplied to the modeling position by transmitting the light beam from the external space of the chamber through the light beam transmitting member.
A control device including a powder supply control unit that controls the operation of the powder supply device and a light beam irradiation control unit that controls the operation of the light beam irradiation device.
With
The control device further
A database showing the relationship between a plurality of input elements and the degree of contamination caused by the metal vapor generated by irradiation of the light beam adhering to the surface of the light beam transmitting member, or the plurality of input elements and the degree of contamination. A storage unit that stores the trained model generated by machine learning as a training data set,
A stain degree estimation unit that estimates the stain degree based on the plurality of input elements and the database or the trained model stored in the storage unit, and a stain degree estimation unit.
An output adjusting unit that adjusts the output of the light beam according to the estimated degree of contamination.
With
The plurality of input elements are at least
The irradiation conditions of the light beam and
The irradiation time of the light beam starting from the first irradiation of the light beam in a state where the surface of the light beam transmitting member is free of dirt, and the irradiation time of the light beam.
Including additional manufacturing equipment. The additional manufacturing apparatus
A gas flow generator for generating a gas flow of an inert gas flowing across between the modeling position and the light beam transmitting member in the manufacturing space in the chamber is provided.
The control device is
A gas flow control unit for controlling the gas flow generator is provided.
The additional manufacturing apparatus according to claim 1, wherein the plurality of input elements include gas flow conditions for the gas flow generated by the gas flow generator. The additional manufacturing apparatus according to claim 1 or 2, wherein the plurality of input elements include a material of the material powder. The output of the light beam adjusted by the output adjusting unit is
It is adjusted based on the estimated degree of contamination so that the input energy of the light beam that is transmitted to the surface of the material powder supplied to the modeling position through the light beam transmitting member is a predetermined amount. The additional manufacturing apparatus according to any one of claims 1-3. The additional manufacturing apparatus
The additional manufacturing apparatus according to any one of claims 1-4, comprising a display device for displaying the degree of stain estimated by the degree of contamination estimation unit. The control device is
The storage unit stores the limit threshold value of the dirt corresponding to the degree of dirt, and also
Claim 1-5 comprising a stain removal instruction device that instructs a user to remove the stain on the light beam transmitting member when the stain degree estimated by the stain degree estimation unit exceeds the limit threshold value. The additional manufacturing apparatus according to any one of the above items. The additional production according to any one of claims 1 to 6, wherein the material powder supplied to the modeling position is melted by irradiation with the light beam and then solidified or sintered to produce the additional product. It is an additional manufacturing method using an apparatus.
A stain degree estimation step for estimating the stain degree based on the plurality of input elements and the database or the trained model stored in the storage unit, and a stain degree estimation step.
An output adjustment step of adjusting the output of the light beam according to the estimated degree of contamination, and
With
The plurality of input elements are at least
The irradiation conditions of the light beam and
The irradiation time of the light beam starting from the first irradiation of the light beam in a state where the surface of the light beam transmitting member is not adhered with the dirt, and the irradiation time of the light beam.
Additional manufacturing methods, including.

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