JP7213220B2 - How to calibrate an additive manufacturing machine - Google Patents

Description

The present invention relates to a method for calibrating an additive manufacturing apparatus.

Various methods are known as a layered manufacturing method for a three-dimensional model. For example, a layered manufacturing apparatus that performs powder bed fusion bonding includes a material layer forming step of forming a material layer in a predetermined modeling region, and a solidification step of forming a solidified layer by irradiating a predetermined irradiation region of the material layer with a laser beam. The steps are repeated to laminate a predetermined number of solidified layers to form a desired three-dimensional structure. In order to prevent deterioration of the material and the solidified layer, the inside of the chamber covering the modeling area is filled with an inert gas of a predetermined concentration during modeling.

An unavoidable deviation may occur between the target position of the laser beam and the actual irradiation position. Therefore, as disclosed in Japanese Unexamined Patent Application Publication No. 2002-100000, it is desirable to measure the displacement amount and correct the irradiation position before forming a desired three-dimensional structure. For example, a laminate manufacturing apparatus that calibrate a laser coordinate system irradiates a calibration plate placed in a modeling area with a laser beam to form an irradiation mark, measures the actual position of the irradiation mark, and measures the target of the irradiation mark. A deviation amount between the position and the actual position is calculated, and correction is performed based on the deviation amount.

Japanese Patent No. 2979431

In order to calibrate the laser coordinate system more accurately, it is desirable to bring the environment inside the chamber closer to the environment during modeling during calibration. Specifically, it is desirable that the chamber be filled with an inert gas atmosphere when calibrating the laser coordinate system.

The environment inside the chamber filled with inert gas is different in temperature and humidity from outside the additive manufacturing apparatus. In particular, since moisture is removed from the inert gas supplied to the chamber, the inside of the chamber is usually drier than the outside of the laminate manufacturing apparatus. Therefore, the calibration plate may change in volume due to changes in temperature, humidity, etc. after it is installed in the chamber. If the volume of the calibration plate changes after the irradiation mark is formed, the position of the irradiation mark shifts, making it impossible to accurately detect the irradiation position.

The present invention has been made in view of such circumstances. It is an object of the present invention to provide a method for calibrating a layered manufacturing apparatus capable of calibrating the

According to the present invention, a material layer forming step of forming a material layer in a modeling region, which is a region for forming a desired three-dimensional model covered with a chamber filled with an inert gas of a predetermined concentration, and a laser beam as a material. A method for calibrating a layered manufacturing apparatus that performs modeling by repeating a solidification step of forming a solidified layer by irradiating a predetermined irradiation region of a layer, comprising: a calibration plate installation step of installing a calibration plate in the modeling region; an inert gas supply step of filling the inert gas, a temporary measurement point forming step of irradiating the calibration plate with a laser beam to form a temporary measurement point, and a temporary measurement point specifying step of specifying the position of the temporary measurement point; an adaptation determination step of determining that the calibration plate has adapted to the environment in the chamber when the amount of displacement of the temporary measurement points is equal to or less than a predetermined threshold after the step of identifying the temporary measurement points at least twice; After it is determined that the environment is suitable, a production measurement point formation step of forming production measurement points with a laser beam with respect to the target position of the calibration plate, and a production measurement point identification step of identifying the positions of the production measurement points. and a correction step of generating correction data specifying a deviation amount at each point of a laser coordinate system based on the irradiation position of the production measurement point specified in the production measurement point specification step. provided.

In the method for calibrating a layered manufacturing apparatus according to the present invention, a temporary measurement point, which is an irradiation mark, is formed on a calibration plate, the position of the temporary measurement point is measured, and the displacement of the position of the temporary measurement point is used to determine whether the calibration plate is within the chamber. determine whether it has adapted to its environment. Since the actual measurement points, which are irradiation traces for generating correction data, are formed after that, the actual measurement points can be formed on the calibration plate adapted to the environment inside the chamber. In this way, the laser coordinate system can be calibrated with high accuracy, and a high-accuracy three-dimensional modeled object can be formed by the appropriately calibrated layered modeling apparatus.

It is a schematic block diagram of the lamination-molding apparatus of this embodiment. It is a schematic block diagram of an irradiation apparatus. It is a block diagram of a control device. It is a flowchart which shows the calibration method of the laser coordinate system of a lamination-molding apparatus. FIG. 4 is an exploded view of the calibration plate; An example of arrangement of temporary measurement points and actual measurement points is shown.

Embodiments of the present invention will be described below with reference to the drawings. Various modifications described below can be implemented in arbitrary combinations.

As shown in FIG. 1 , the layered manufacturing apparatus 1 of this embodiment includes a chamber 11 , a material layer forming device 3 , an irradiation device 4 , a cutting device 5 and an imaging device 6 .

The chamber 11 is configured to be substantially closed and covers a modeling region R, which is a region in which a desired three-dimensional modeled object is to be formed. During modeling, the chamber 11 is filled with an inert gas of a predetermined concentration. Also, the inert gas containing fumes generated during the formation of the solidified layer 85 is discharged from the chamber 11 . Desirably, the inert gas discharged from the chamber 11 is returned into the chamber 11 after fumes are removed. The layered manufacturing apparatus 1 of this embodiment includes an inert gas supply device 21 and a fume collector 23 as an inert gas supply/discharge mechanism.

The inert gas supply device 21 supplies inert gas of a predetermined concentration to the chamber 11 . The inert gas supply device 21 is, for example, an inert gas generator that generates inert gas from air, or a gas cylinder that stores inert gas. In this embodiment, the inert gas supply device 21 is, for example, a PSA nitrogen generator or a membrane separation nitrogen generator.

In the present invention, the inert gas refers to a gas that does not substantially react with the material layer 83 and the solidified layer 85, and is selected from nitrogen gas, argon gas, helium gas, etc., according to the type of material. . In order to supply the inert gas of high purity, it is desirable that the inert gas supplied from the inert gas supply device 21 is sufficiently dry. Specifically, when the inert gas supply device 21 is an inert gas generator, it is desirable to have a dryer for drying the air that is the material of the inert gas. Moreover, when the inert gas supply device 21 is a gas cylinder, it is desirable to fill it with sufficiently dried inert gas.

The fume collector 23 removes fumes from the inert gas discharged from the chamber 11 and returns the fumes to the chamber 11 . Fume collector 23 is, for example, an electrostatic precipitator or a filter.

An inert gas supply port and an inert gas discharge port connected to the inert gas supply device 21 or the fume collector 23 are appropriately provided on the wall surface of the chamber 11, the device inside the chamber 11, or the like. Any number of supply ports and discharge ports may be provided at any position.

A material layer forming apparatus 3 is provided in the chamber 11 and forms a material layer 83 having a predetermined thickness. The material layer forming apparatus 3 includes a base 31 having a modeling area R and a recoater head 33 arranged on the base 31 . The recoater head 33 is horizontally movable by a recoater head driving device 35 having an arbitrary actuator. A modeling table 37 is arranged in the modeling area R. As shown in FIG. The modeling table 37 is configured to be vertically movable by a modeling table driving device 39 having an arbitrary actuator. During modeling, the base plate 81 may be placed on the modeling table 37 , and the first material layer 83 is formed on the base plate 81 .

The recoater head 33 includes a material container, a material supply port, and a material discharge port. The material storage part stores the material. In this embodiment, the material is, for example, metal powder. The material supply port is provided on the upper surface of the material container and serves as a port for receiving material supplied from a material supply device (not shown) to the material container. The material discharge port is provided on the bottom surface of the material container and discharges the material in the material container. The material discharge port has a slit shape extending in a horizontal direction perpendicular to the moving direction of the recoater head 33 . The sides of the recoater head 33 are provided with blades for leveling the material to form the material layer 83 . The recoater head 33 horizontally reciprocates over the modeling area R while ejecting the material accommodated in the material accommodating portion from the material ejection port. At this time, the blade planarizes the expelled material to form material layer 83 .

The irradiation device 4 is provided above the chamber 11 . The irradiation device 4 irradiates a predetermined irradiation area of the material layer 83 formed on the modeling area R with the laser beam L to melt or sinter the material layer 83 at the irradiation position to form the solidified layer 85 . The irradiation area exists within the modeling area R and roughly coincides with the area surrounded by the contour shape of the three-dimensional modeled object in the predetermined divided layer. As shown in FIG. 2, the irradiation device 4 includes a laser light source 41, a collimator 43, a focus control unit 45, and a scanning device 47.

A laser light source 41 generates a laser beam L. As shown in FIG. Here, the type of laser light L is not limited as long as it can sinter or melt the material layer 83, and is, for example, a fiber laser, a _CO2 laser, a YAG laser, a green laser, or a blue laser. The collimator 43 converts the laser light L output from the laser light source 41 into parallel light. The focus control unit 45 has a focus adjustment lens 451 and a lens actuator 453 that moves the focus adjustment lens 451 back and forth, and adjusts the laser light L output from the laser light source 41 to a desired spot diameter. The scanning device 47 is, for example, a galvanometer scanner. The scanning device 47 includes an X-axis galvanometer mirror 471 , an X-axis mirror actuator 473 that rotates the X-axis galvanometer mirror 471 , a Y-axis galvanometer mirror 475 , and a Y-axis mirror actuator 477 that rotates the Y-axis galvanometer mirror 475 . have. The X-axis galvanometer mirror 471 and the Y-axis galvanometer mirror 475 are controlled in rotation angle, and two-dimensionally scan the laser light L output from the laser light source 41 .

The laser light L that has passed through the X-axis galvanometer mirror 471 and the Y-axis galvanometer mirror 475 is transmitted through the window 13 provided on the upper surface of the chamber 11 and is irradiated onto the material layer 83 formed in the modeling area R. The window 13 is made of a material that allows the laser light L to pass therethrough. For example, if the laser light L is a fiber laser or YAG laser, the window 13 can be made of quartz glass.

A contamination prevention device 15 is provided on the upper surface of the chamber 11 so as to cover the window 13 . The pollution control device 15 includes a cylindrical housing and a cylindrical diffusion member disposed within the housing. An inert gas supply space is provided between the housing and the diffusion member. Further, an opening is provided in the bottom surface of the housing inside the diffusion member. The diffusion member is provided with a large number of pores, and the clean chamber is filled with the clean inert gas supplied to the inert gas supply space through the pores. Then, the clean inert gas filled in the clean room is jetted downward from the pollution control device 15 through the opening. In this manner, fume is prevented from adhering to the window 13 .

The cutting device 5 cuts the surface of the solidified layer 85 and unnecessary portions. The cutting device 5 includes a machining head 51 , a machining head driving device 53 , a spindle 55 , a spindle motor 57 and a cutting tool 59 . The machining head driving device 53 may have any actuator that moves the machining head 51 to a desired position within the chamber 11 . For example, the machining head driving device 53 includes an X-axis driving device that moves the machining head 51 in the X-axis direction, which is a predetermined horizontal direction, and a Y-axis driving device that moves the machining head 51 in the Y-axis direction, which is a horizontal direction orthogonal to the X-axis. It has a Y-axis driving device and a Z-axis driving device for moving the machining head 51 in the Z-axis direction, which is a predetermined vertical direction.

A spindle 55 is provided on the processing head 51 . The spindle 55 holds a cutting tool 59 such as an end mill and is configured to be rotated by a spindle motor 57 . A cutting tool 59 rotated by a spindle 55 cuts the surface of the solidified layer 85 and unnecessary portions.

Note that the layered manufacturing apparatus 1 may not include a cutting device, and the cutting device may have another configuration. For example, a cutting device includes a machining head provided with a turning mechanism that holds a cutting tool such as a cutting tool and rotates the cutting tool along a vertical rotation axis, and a machining head drive for horizontally driving the machining head. may include a device. The machining head driving device includes, for example, a pair of first horizontal movement mechanisms, a gantry provided in the pair of first horizontal movement mechanisms, and a second horizontal movement mechanism attached to the gantry and to which the machining head is fixed. , has

The imaging device 6 captures images of the temporary measurement point 63 and the actual measurement point 65 to acquire the position information of the temporary measurement point 63 and the actual measurement point 65 when calibrating the laser coordinate system, which will be described later. The temporary measurement point 63 and the actual measurement point 65 are markings formed on the calibration plate 61 by the irradiation of the laser beam L and recognizable by the imaging device 6. Hereinafter, the temporary measurement point 63 and the actual measurement point 65 are included. It's called radiation marks. The imaging device 6 may have any imaging element capable of imaging irradiation traces, and is a CCD camera in this embodiment.

In this embodiment, the imaging device 6 is configured to be movable to a desired position within the chamber 11 . More specifically, the imaging device 6 is provided on the processing head 51 and configured to be movable to a desired position within the chamber 11 by a processing head driving device 53 . However, a drive device for moving the imaging device 6 may be provided separately. In addition, if the area that can be imaged by the imaging device 6 includes all irradiation traces, the imaging device 6 may be fixed at a predetermined position within the chamber 11 .

Here, the control device 7 of the layered manufacturing apparatus 1 will be described. As shown in FIG. 3, the control device 7 of this embodiment includes a main control device 71, an irradiation control device 73, an imaging control device 75, drivers 771, 772, 773, 774, 775, 776, and 777. ,including. The main control device 71, the irradiation control device 73, and the imaging control device 75 may each be configured by arbitrarily combining hardware and software. ing. Further, in the present embodiment, the main controller 71, the irradiation control device 73, and the imaging control device 75 are configured separately. One or more may be integrally configured.

The main controller 71 controls the recoater head 33, the modeling table 37, the processing head 51 and the spindle 55 via drivers 771, 772, 773 and 774 according to a project file created by a CAM device (not shown). In addition, the main controller 71 sends a modeling program including commands such as the irradiation position of the laser beam L among the project files to the irradiation controller 73 .

Furthermore, in calibrating the laser coordinate system, the main controller 71 drives the processing head 51 to move the imaging device 6 to a position where irradiation traces can be imaged, and controls the irradiation control device 73 to control the laser beams related to the formation of the irradiation traces. A command for irradiation of L is sent, and a command for imaging an irradiation mark is sent to the imaging control device 75 . Based on the coordinate data of the actual irradiation position of the temporary measurement point 63 acquired from the imaging control device 75, it is determined whether the calibration plate 61 has adapted to the environment inside the chamber 11 or not. Note that the above control related to the main controller 71 may be performed by the irradiation control device 73 or the imaging control device 75 .

The irradiation control device 73 controls the irradiation device 4 based on the modeling program sent from the main control device 71 and the correction data of the laser coordinate system. Specifically, the irradiation control device 73 controls the rotation angles of the X-axis galvanometer mirror 471 and the Y-axis galvanometer mirror 475 via drivers 775 and 776, and controls the irradiation position of the laser beam L. FIG. The irradiation control device 73 also controls the position of the focusing lens 451 via the driver 777 to adjust the focus position. Further, the irradiation control device 73 controls the laser light source 41 to adjust the intensity of the laser light L and switch on/off.

Furthermore, in calibrating the laser coordinate system, the irradiation control device 73 controls the irradiation device 4 based on the irradiation command sent from the main control device 71 to form an irradiation trace at a desired position on the calibration plate 61 . Further, the irradiation control device 73 compares the coordinate data of the target position of the actual measurement point 65 with the coordinate data of the actual irradiation position of the actual measurement point 65 acquired from the imaging control device 75, and Generates correction data specifying the amount of deviation in . Note that the above control related to the irradiation control device 73 may be performed by the main control device 71 or the imaging control device 75 .

In calibrating the laser coordinate system, the imaging control device 75 images the temporary measurement point 63 and the actual measurement point 65, which are irradiation traces, based on the imaging command sent from the main controller 71. The position information of the measurement point 65 is acquired. The imaging control device 75 analyzes the acquired position information, digitizes it as coordinate data, and sends it to the main control device 71 and the irradiation control device 73 . Note that the above control related to the imaging control device 75 may be performed by the main control device 71 or the irradiation control device 73 .

In forming a desired three-dimensional modeled object with the layered manufacturing apparatus 1 described above, the laser coordinate system is calibrated in advance. Calibration of the laser coordinate system may be performed at arbitrary timing such as after machine adjustment or before starting modeling. Preferably, calibration of the laser coordinate system is performed each time a build is started. As shown in FIG. 4, the method for calibrating the layered manufacturing apparatus 1 of the present embodiment includes an electrostatic adsorption step (S11), a calibration plate installation step (S12), an inert gas supply step (S13), a temporary measurement A point formation step (S14), a temporary measurement point identification step (S15), an adaptation determination step (S16), an actual measurement point formation step (S17), an actual measurement point identification step (S18), and a correction step (S19). ) and

For calibration, a calibration plate 61 for forming irradiation traces is prepared. As the calibration plate 61, any one can be used as long as it can form an irradiation trace, but it is preferable to use a plate that has a flat surface and is relatively insusceptible to temperature, humidity, and the like. The calibration plate 61 may comprise an irradiation target 611 and a substrate 613 to which the irradiation target 611 is attached. The irradiation target 611 is a sheet-like member capable of forming an irradiation mark by irradiation with the laser beam L, and is, for example, black paper or thermal paper. The substrate 613 has a flat plate 613a which is a flat plate-like member. The flat plate 613a may have any desired flatness, but when performing the electrostatic attraction process, the flat plate 613a is desirably a dielectric material, for example, a glass plate. Further, when performing the electrostatic adsorption step, in order to perform electrostatic adsorption more preferably, a dielectric sheet 613b is attached to the upper surface of the flat plate 613a, that is, the surface on which the irradiation target 611 is adsorbed. is desirable. The dielectric sheet 613b is a sheet-like member made of a dielectric. More specifically, in this embodiment, the label layer of the electrostatic adsorption sheet is used as the dielectric sheet 613b. The electrostatic adsorption sheet is a laminate obtained by laminating a label layer including a resin film layer and a support layer to which the label layer is electrostatically adsorbed. Adsorption (registered trademark). In this embodiment, as shown in FIG. 5, a calibration plate 61 is constructed by electrostatically attracting an irradiation target 611 to a substrate 613 consisting of a flat plate 613a and a dielectric sheet 613b.

In this embodiment, an electrostatic chucking step is performed to obtain the calibration plate 61 . First, a charge is applied to the substrate 613 by a charging device such as a corona charging gun or a triboelectric charging gun to charge the substrate 613 . By placing the irradiation target 611 on the substrate 613 , the irradiation target 611 is electrostatically attracted to the substrate 613 . The amount of change in volume due to environmental changes is typically different between irradiation target 611 and substrate 613 . In this embodiment, since the irradiation target 611 is electrostatically attracted to the substrate 613, it can move horizontally to some extent. Therefore, since the irradiation target 611 is displaced according to the volume change of the irradiation target 611 or the substrate 613, the irradiation target 611 is less likely to wrinkle even if the environment changes. In this way, irradiation traces can be formed with higher accuracy.

Next, a step of installing a calibration plate is performed. A calibration plate 61 is placed on the modeling area R in the chamber 11 , that is, on the modeling table 37 . Preferably, the position of the modeling table 37 is adjusted so that the upper surface position of the calibration plate 61 coincides with the upper surface position of the material layer 83 during lamination manufacturing later.

After setting the calibration plate 61, an inert gas supply step is performed. The inert gas supply device 21 supplies inert gas to the chamber 11 so that the chamber 11 is filled with the inert gas. The type and concentration of the inert gas supplied to the chamber 11 are desirably the same as during the subsequent layered manufacturing. It is preferable that the inert gas supply step is continued at least until the actual measurement point identification step. The humidity inside the chamber 11 is, for example, about 8% when the humidity outside the laminate manufacturing apparatus is about 60%. The temperature inside the chamber 11 is, for example, about 25.0°C when the humidity outside the laminate manufacturing apparatus is about 24.5°C. Thus, there is a large difference in humidity between inside the chamber 11 and outside the laminate molding apparatus.

Then, a temporary measurement point forming step is performed. The irradiation device 4 irradiates the irradiation target 611 of the calibration plate 61 with the laser light L, and the temporary measurement point 63 is formed. At this time, the intensity of the laser light L is set sufficiently low so that the laser light L does not penetrate the calibration plate 61 and damage the modeling table 37 . Also, the target position of the temporary measurement point 63 is set to an arbitrary position within a range that does not affect the formation and imaging of the final measurement point 65 . In this embodiment, as shown in FIG. 6, four temporary measurement points 63 are arranged at the upper left, upper right, lower right, and lower left of the irradiation target 611, respectively. Note that the number of temporary measurement points 63 is not particularly limited. Moreover, the shape of the temporary measurement point 63 may be, for example, a circle or a cross shape composed of two line segments.

After forming the temporary measurement points 63, a temporary measurement point specifying step is performed. The imaging device 6 is moved directly above the temporary measurement point 63 and images the temporary measurement point 63 to obtain image data. The imaging control device 75 analyzes the image data and identifies the actual irradiation position of the temporary measurement point 63 . For example, when the shape of the temporary measurement point 63 is a circle, the imaging control device 75 calculates the position of the center of gravity of the circle and uses this position as the coordinates of the temporary measurement point 63 . For example, when the shape of the temporary measurement point 63 is cross-shaped, the imaging control device 75 calculates the position of the intersection of the line segments forming the temporary measurement point 63 and uses this position as the coordinates of the temporary measurement point 63 . After that, the temporary measurement point specifying step is performed again by the same procedure.

After performing the temporary measurement point identification step, a predetermined time wait may be performed to wait for the calibration plate 61 to adapt before performing the next temporary measurement identification step. The waiting time may be of any length, but for example, a value approximately equal to or longer than the time from the start of the production measurement point formation process to the end of the production measurement point identification process is set as the waiting time. preferably. By performing the adaptation judgment process after setting such a standby time, even if the time required for the actual measurement point formation process and the actual measurement point identification process has passed, displacement in an unacceptable range will not occur. It can be more suitably determined that the calibration plate 61 is conforming to a certain extent.

After completing the two temporary measurement point identification steps, the adaptation determination step is performed. The main controller 71 compares the coordinates of the actual irradiation position of the latest temporary measurement point 63 with the coordinates of the actual irradiation position of the previous temporary measurement point 63, and the displacement amount of the temporary measurement point 63, that is, It is determined whether the absolute value of the difference between the two coordinates is less than or equal to a predetermined threshold. When the amount of displacement of the temporary measurement point 63 exceeds a predetermined threshold, it is determined that the calibration plate 61 has not yet adapted to the environment inside the chamber 11 . In this case, the temporary measurement point identification step and the adaptation determination step are performed again after the predetermined time has elapsed. When the displacement amount of the temporary measurement point 63 is equal to or less than a predetermined threshold value, it is determined that the calibration plate 61 has sufficiently adapted to the environment inside the chamber 11 .

After conforming the calibration plate 61, the actual measurement point formation process is performed. Similar to the temporary measurement point forming step, the irradiation device 4 irradiates the irradiation target 611 of the calibration plate 61 with the laser light L, and the actual measurement point 65 is formed. At this time, the intensity of the laser light L is set sufficiently low so that the laser light L does not penetrate the calibration plate 61 and damage the modeling table 37 . Although the number of the final measurement points 65 is not particularly limited, it is desirable that the target positions of the final measurement points 65 be distributed over the entire modeling region R. In FIG. 6, a total of 25 actual measurement points 65 are displayed in consideration of visibility. They are arranged in a grid pattern on the irradiation target 611 . Also, the shape of the production measurement point 65 may be, for example, a circle or a cross shape composed of two line segments. When the shape of the actual measurement point 65 is circular, the target position of the actual measurement point 65 is the center of gravity of the circle. When the actual measurement point 65 has a cross shape, the target position of the actual measurement point 65 is the position of the intersection of the line segments.

After forming the production measurement points 65, the production measurement point identification step is performed. The imaging device 6 is moved directly above the actual measurement point 65 and images the actual measurement point 65 to obtain image data. The imaging control device 75 analyzes the image data and identifies the actual irradiation position of the actual measurement point 65 . For example, when the shape of the actual measurement point 65 is circular, the imaging control device 75 calculates the position of the center of gravity of the circle and uses this position as the coordinates of the actual measurement point 65 . For example, when the final measurement point 65 has a cross shape, the imaging control device 75 calculates the position of the intersection of the line segments forming the final measurement point 65 and uses this position as the coordinates of the final measurement point 65 .

After obtaining the coordinates of the actual irradiation position of the actual measurement point 65, a correction process is performed. The irradiation control device 73 compares the coordinates of the target position of the production measurement point 65 with the coordinates of the actual irradiation position of the production measurement point 65, and obtains the amount of deviation between the target position and the actual irradiation position. The irradiation control device 73 also estimates and obtains the amount of deviation at coordinates other than the coordinates at which the actual measurement point 65 is formed, based on the amount of deviation of the actual measurement point 65 . In this manner, the irradiation control device 73 generates correction data specifying the amount of deviation at each point in the laser coordinate system. This correction data is used in subsequent layered manufacturing.

In the calibration method of this embodiment, after confirming that the calibration plate 61 is adapted to the environment inside the chamber 11 based on the amount of displacement of the temporary measurement points 63, the actual measurement points 65 are formed and captured. Therefore, the actual measurement point 65 is less likely to be displaced during calibration, and more accurate correction data for the laser coordinate system can be obtained.

The lamination-molding apparatus 1 calibrated as described above performs lamination-molding to obtain a desired three-dimensional modeled object. The method for manufacturing a three-dimensional structure according to this embodiment includes a base plate installation process, an inert gas supply process, a material layer formation process, a solidification process, and a cutting process.

First, a base plate setting step of setting the base plate 81 on the modeling table 37 and an inert gas supply step of filling the chamber 11 with an inert gas of a predetermined concentration are performed.

Subsequently, a material layer forming step of forming the material layer 83 in the modeling region R is performed. The modeling table 37 is adjusted to an appropriate height for forming the material layer 83 having a predetermined thickness, and the recoater head 33 moves horizontally over the modeling area R. The material dispensed from recoater head 33 is leveled by the blade to form material layer 83 .

Then, a solidification step of forming a solidified layer 85 by irradiating a predetermined irradiation region of the material layer 83 with the laser light L from the irradiation device 4 is performed. At this time, the command for the irradiation position of the laser beam defined in the modeling program is corrected by the correction data of the laser coordinate system.

By repeating the material layer forming process and the solidifying process as described above, a plurality of solidified layers 85 are laminated to manufacture a desired three-dimensional structure.

A cutting step may be performed to cut the surface of the solidified layer 85 each time a predetermined number of solidified layers 85 are formed. By performing the cutting process, a three-dimensional modeled object with higher accuracy can be obtained.

As some examples have already been specifically shown, the present invention is not limited to the configurations of the embodiments shown in the drawings, and various modifications and applications are possible without departing from the technical idea of the present invention. is.

For example, in the present embodiment, the substrate 613 composed of the flat plate 613a and the dielectric sheet 613b is charged and the irradiation target 611 is electrostatically attracted. may be held at For example, an electrostatic chuck or a vacuum chuck may be used as the substrate, and the irradiation target 611 may be held on the substrate 613 by electrostatic adsorption or vacuum adsorption.

1 laminate molding apparatus 11 chamber 61 calibration plate 63 temporary measurement point 65 final measurement point 83 material layer 85 solidified layer 611 irradiation target 613 substrate 613a flat plate 613b dielectric sheet L laser beam R molding region

Claims (4)

A material layer forming step of forming a material layer in a modeling region, which is a region for forming a desired three-dimensional model covered with a chamber filled with an inert gas of a predetermined concentration, and irradiating the material layer with a laser beam in a predetermined manner. A method for calibrating a layered manufacturing apparatus that performs modeling by repeating a solidification step of irradiating a region to form a solidified layer,
a calibration plate installation step of installing a calibration plate in the modeling area;
an inert gas supply step of filling the chamber with the inert gas;
a temporary measurement point forming step of irradiating the calibration plate with the laser beam to form a temporary measurement point at an arbitrary target position ;
a temporary measurement point identifying step of identifying an actual position of the temporary measurement point at the target position ;
After performing the temporary measurement point specifying step again to re-identify the actual position of the temporary measurement point at the target position , the coordinates of the actual position of the temporary measurement point at the re-specified target position and one The coordinates of the actual position of the temporary measurement point at the same target position identified in the previous temporary measurement point identification step are compared with each other, and the amount of displacement, which is the absolute value of the difference between the two coordinates, is a predetermined threshold value. an adaptation determination step for determining that the calibration plate has adapted to the environment in the chamber when:
The adaptation determination step is repeated until it is determined that the calibration plate has adapted to the environment within the chamber, and after it is determined that the calibration plate has adapted to the environment within the chamber, the calibration plate is moved to a target position. On the other hand, a production measurement point forming step of forming a production measurement point with the laser beam;
a production measurement point identifying step of identifying the position of the production measurement point;
A method for calibrating a layered manufacturing apparatus, comprising: a correction step of generating correction data specifying a deviation amount at each point in a laser coordinate system based on the irradiation position of the production measurement point specified in the production measurement point specifying step. . The laminate manufacturing apparatus according to claim 1, wherein when there are a plurality of the temporary measurement points formed in the temporary measurement point forming step, the temporary measurement point specifying step and the adaptation determination step are performed at all the temporary measurement points. calibration method. The laminate manufacturing apparatus according to claim 1, wherein the calibration plate includes an irradiation target capable of forming the temporary measurement point and the final measurement point by irradiation with the laser beam, and a substrate to which the irradiation target is attached. Calibration method. 3. The laminate manufacturing apparatus according to claim 2, further comprising an electrostatic attraction step of charging the substrate and electrostatically attracting the irradiation target to the charged substrate to obtain the calibration plate before the step of installing the calibration plate. calibration method.

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