JP2025022204A - Powder material laying device, powder material laying method, and program - Google Patents

Abstract

To provide a powder material laying device, a powder material laying method, and a program that are capable of appropriately adjusting a stack height of powder material.SOLUTION: A powder material laying device for laying a powder material in an additive manufacturing process includes: a container of the powder material having an opening for dropping the powder material; a vibration part that applies vibration to the container; a moving part that moves the container; a sensor that measures a stacking height of molded layers formed by the powder material dropped from the container; and a control part that adjusts at least one of a moving speed and a vibration strength of the container based on a measured stack height and a target stack height.SELECTED DRAWING: Figure 1

Description

This disclosure relates to a powder material laying device, a powder material laying method, and a program.

Patent Document 1 shows an example of the configuration of a powder bed three-dimensional printer that distributes modeling powder through a sheet screen by vibrating the sheet screen having multiple through-holes with an ultrasonic vibrator. The powder bed three-dimensional printer described in Patent Document 1 is said to be able to reduce the tendency of a recoater to distribute modeling powder unevenly due to local variations in vibration in the absence of such changes by changing at least one of the size, shape, and distribution of the through-holes in the sheet screen.

Special Publication No. 2020-524095

It is noted that Patent Document 1 states that the ultrasonic transducer may include electronic circuitry incorporating temporary or periodic automatic tuning for adjusting at least one of the frequency and amplitude of the output vibration to achieve a desired level or consistency of the build powder flow rate through the sheet screen. However, Patent Document 1 does not specifically disclose how to perform automatic tuning, such as how to adjust the frequency or amplitude of the output vibration to adjust the build powder flow rate.

The present disclosure has been made in consideration of the above circumstances, and aims to provide a powder material laying device, a powder material laying method, and a program that can appropriately adjust the stack height of the powder material.

In order to achieve the above object, the powder material laying device according to the present disclosure is a device for laying powder material in an additive manufacturing process, and includes a container for the powder material having an opening for dropping the powder material, a vibration unit for applying vibration to the container, a moving unit for moving the container, a sensor for measuring the stack height of a modeling layer formed by the powder material dropped from the container, and a control unit for adjusting at least one of the moving speed or the vibration strength of the container based on a measured stack height, which is the measured stack height, and a target stack height.

The powder material laying method according to the present disclosure is a method for laying powder material in an additive manufacturing process, and includes the steps of measuring the stack height of a modeling layer formed by the powder material dropped from the container using a container for the powder material having an opening for dropping the powder material, a vibration unit for applying vibration to the container, and a moving unit for moving the container, and adjusting at least one of the moving speed of the container or the strength of the vibration based on a measured stack height, which is the measured stack height, and a target stack height.

The program disclosed herein is a program for laying powder material in an additive manufacturing process, and causes a computer to execute the steps of measuring the stack height of a modeling layer formed by the powder material dropped from a container using a container for the powder material having an opening for dropping the powder material, a vibration unit that imparts vibration to the container, and a movement unit that moves the container, and adjusting at least one of the movement speed or vibration strength of the container based on a measured stack height, which is the measured stack height, and a target stack height.

The powder material laying device, powder material laying method, and program disclosed herein allow the stack height of the powder material to be appropriately adjusted.

FIG. 1 is a schematic diagram showing a configuration example of a powder material laying device according to an embodiment of the present disclosure. FIG. 1 illustrates a front view of a powder container according to an embodiment of the present disclosure. FIG. 13 illustrates a side view of a powder container according to an embodiment of the present disclosure. FIG. 2 is a control block diagram of a powder material laying device according to an embodiment of the present disclosure. FIG. 2 is a schematic diagram illustrating an example of a sieve according to an embodiment of the present disclosure. 1 is a flowchart illustrating a procedure of a powder material laying method according to an embodiment of the present disclosure. FIG. 1 is a schematic block diagram illustrating a configuration of a computer according to an embodiment of the present disclosure.

The powder material laying device, the powder material laying method, and the program according to the embodiment of the present disclosure will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration example of the powder material laying device 10 according to the embodiment of the present disclosure. FIG. 2 is a front view of the powder container 11 according to the embodiment of the present disclosure. FIG. 3 is a side view of the powder container 11 according to the embodiment of the present disclosure. FIG. 4 is a control block diagram of the powder material laying device 10 according to the embodiment of the present disclosure. FIG. 5 is a schematic diagram showing an example of a sieve 11b according to the embodiment of the present disclosure. FIG. 6 is a flowchart showing the procedure of the powder material laying method according to the embodiment of the present disclosure. FIG. 7 is a schematic block diagram showing the configuration of a computer according to the embodiment of the present disclosure. Note that the same or corresponding configurations in each figure are designated by the same reference numerals and the description will be omitted as appropriate.

(Configuration of powder material laying device)
1 illustrates a schematic configuration example of a powder material laying device 10 according to an embodiment of the present disclosure, and an additive manufacturing device 1 including the powder material laying device 10. The additive manufacturing device 1 illustrated in FIG. 1 includes a three-dimensional modeling laser scanner 2 and the powder material laying device 10.

The additive manufacturing device 1 is a device that manufactures a model 20 by stacking modeling layers 20L made of, for example, powder material 17 using an additive manufacturing (AM) process. The additive manufacturing process is a processing method that combines materials based on three-dimensional model data to materialize a model. The modeling layers 20L are materials that are spread or applied in layers to form a surface. In this embodiment, the modeling layers 20L include a state in which the powder material 17 is laid (powder layer state) and a state in which the powder material is bonded by a modeling laser beam. Also, FIG. 1 shows an example in which the model 20 is integrally formed with the workpiece 21 so as to fill the recess 21a of the workpiece 21 using a powder bed bonding fusion process, which is one of the additive manufacturing processes. In this case, the modeling layer 20L is added as a modeling surface, for example, a curved modeling surface 21b and the modeling layer 20L that was deposited just before. Powder Bed Fusion (PBF) is an additive manufacturing process that uses thermal energy to selectively melt and solidify a powder bed. The build surface is the area where material is added.

The 3D laser scanner 2 for modeling uses one or more lasers to irradiate laser light (laser light for modeling) using laser sintering technology, repeatedly melting or dissolving particles on the surface of the modeling layer 20L, forming a model 20 from the powder material 17. The 3D laser scanner 2 for modeling controls the irradiation position of the laser light in three directions: X, Y, and Z.

The powder material laying device 10 is a device for laying powder material 17 in an additive manufacturing process. The powder material laying device 10 includes a powder container (hereinafter also simply referred to as a container) 11, a vibration unit 12, a moving unit 13, and a sensor 14.

The powder container 11 is a container for the powder material 17, having an opening 11a for dropping the powder material 17. The powder container 11 drops the powder material 17 while moving in the X direction by the moving part 13, and lays down a powder layer of a predetermined thickness (for example, 50 μm per layer). Figures 2 and 3 show an example of the configuration of the powder container 11. Note that the correspondence of the directions in Figures 1 to 3 is shown by the XYZ axes. As shown in Figures 1 to 3, the powder container 11 has an opening 11a and a supply port 11c for the powder material 17. A sieve 11b is provided in the opening 11a. In addition, a vibration part 12 and a vibration part 16 for vibrating the powder container 11 are attached to the outer wall surface 11d of the powder container 11.

The vibration unit 12 is, for example, a piston-type air vibrator, which applies vibrations to the powder container 11 due to reciprocating impact caused by the reciprocating motion of the piston, causing the powder material 17 in the powder container 11 to be ejected from the opening 11a through the sieve 11b, and causing the powder material 17 to fall so that it is sprayed onto the modeling surface. The vibration unit 16 is, for example, an ultrasonic vibrator, which generates vibrations to remove clogging from the sieve 11b, for example, when cleaning the sieve 11b. Note that the "vibration unit" according to the present disclosure includes at least one of the vibration unit 12 and the vibration unit 16.

The sieve 11b has a size of opening W that allows the powder material 17 to fall in a predetermined vibration state. Alternatively, the sieve 11b has a size of opening W that does not allow the powder material 17 to fall without vibration. Alternatively, the sieve 11b has a size of opening W that does not allow the powder material 17 to fall without vibration and allows the powder material 17 to fall in a predetermined vibration state. Figure 5 shows an example of the opening W of the sieve and the diameter d of the metal wire when the sieve 11b is a metal sieve net. For example, when the powder particle size of the powder material 17 is 10 to 45 μm, the opening W of the sieve 11b is set to a size equal to or several μm larger than the maximum size of the powder (for example, about 53 μm), so that multiple powders do not pass through the opening W at the same time and the powder does not pass through when vibration is not applied. In addition, in this embodiment, powder that has been passed through the sieve 11b in advance is used to prevent the sieve 11b from clogging with powder. That is, in this embodiment, when forming the model 20, the powder material 17 that has passed through the sieve 11b at least once is placed in the powder container 11.

The powder container 11 is supported by the moving part 13 via a jig 31 and moves in the direction indicated by the white arrow. The moving part 13 is a linear guide that uses, for example, a linear motor as a drive source.

The sensor 14 is a sensor that measures the stacking height of the modeling layer 20L formed by the powder material 17 dropped from the powder container 11. The sensor 14 is, for example, a thickness measurement sensor such as a laser displacement meter that uses laser light (measurement laser light) to measure the distance in the Z direction at multiple measurement points on the XY plane. The sensor 14 is supported by the moving unit 13 via the jig 31 and moves in the moving direction indicated by the white arrow. The sensor 14 measures the thickness, for example, after the powder is laid and after the laser light is irradiated, under the control of the control unit 15. The sensor 14 acquires a measurement value of, for example, the height (h1, h2, etc. in FIG. 1) (thickness) of one or multiple stacked modeling layers 20L (in this embodiment, the height of one or multiple modeling layers 20L is referred to as the stacking height of the modeling layers 20L) or the Z direction position of the surface of the modeling layer 20L and the height (h0 in FIG. 1) (thickness) or the Z direction position of the surface of the workpiece 21.

The control unit 15 adjusts at least one of the moving speed or the vibration strength of the powder container 11 as necessary based on the measured stacking height, which is the measured stacking height, and the target stacking height. The target stacking height is the stacking height that is the design target for the number of stacks. For example, when the measured stacking height is smaller than the target measurement height, the control unit 15 increases the laying amount by decreasing the moving speed or increasing the vibration strength. Also, when the measured stacking height is larger than the target measurement height, the control unit 15 decreases the laying amount by increasing the moving speed or decreasing the vibration strength. For example, the control unit 15 can adjust the moving speed and the vibration strength simultaneously, adjust only the moving speed, or adjust only the vibration strength, depending on the deviation between the measured stacking height and the target measurement height. Also, the control unit 15 may adjust for each laying operation, or may adjust for each predetermined number of times. Also, the control unit 15 may adjust for each laser light irradiation operation, or may adjust for each predetermined number of times. Note that "adjusting...if necessary" means, for example, that adjustment is made if the difference between the measured stacking height and the target stacking height is not within a predetermined range, or that adjustment is made if the adjustment is made after a predetermined number of laying operations or laser light irradiation operations. Also, for example, when adjustment is made after a plurality of laying operations or laser light irradiation operations, the control unit 15 may omit measuring the laying height or stacking height with the sensor 14 in the case of operations that do not require adjustment.

As shown in FIG. 4, the control unit 15 acquires the measurement results of the sensor 14 and controls the vibration strength (or even frequency) of the vibration excitation unit 12, the moving speed and moving position of the powder container 11 by the moving unit 13, and the moving position of the sensor 14 by the moving unit 13. The control unit 15 also controls the irradiation position of the laser light of the three-dimensional laser scanner for modeling by sending and receiving a predetermined control signal to and from the three-dimensional laser scanner for modeling. The control unit 15 also has a function of controlling the measurement of the stack height, etc. by the sensor 14 according to, for example, input instructions from an operator, and manually setting the moving speed and vibration strength.

(Example of operation of powder material laying device)
An operation example of the powder material laying device 10 will be described with reference to Fig. 6. In the example shown in Fig. 6, first, for example, the powder material 17 is manually sorted in advance by passing it through a sieve 11b, and only the powder material 17 that has passed through is selected (step S10). The sieve 11b may be provided in the powder container 11, or, for example, a separate powder container and sieve for sorting may be prepared and used. During sorting, the powder material 17 remaining in the powder container 11 is taken out of the powder container 11 and is regarded as unused material. It is assumed that this operation example is an operation example aimed at laying a modeling layer 20L having a thickness (for example, 50 μm) suitable for laser sintering processing in one laying operation.

Next, the powder material 17, which has been selected (picked) manually, is stored in the powder container 11 (step S11).

Next, the amount of powder applied is adjusted, for example manually (step S12). In step S12, the application status is first visually confirmed, and the amount of powder applied is adjusted by adjusting the vibration strength of the vibration unit 12. Furthermore, the powder container 11 is moved at a constant speed, the amount of powder applied is measured, and the vibration strength is readjusted.

Next, the control unit 15 uses the sensor 14 to measure the height of the workpiece 21 (step S13). This height of the workpiece 21 becomes the reference height before molding.

Next, the control unit 15 vibrates the vibration unit 12 at the set vibration intensity and moves the powder container 11 at the set moving speed to lay down the powder material 17 (step S14).

Next, the control unit 15 uses the sensor 14 to measure the powder application height (step S15).

Next, the control unit 15 transmits and receives a predetermined control signal to and from the 3D laser modeling scanner 2, thereby irradiating the laid powder material 17 with laser light to form the modeling layer 20L (step S16).

Next, the control unit 15 uses the sensor 14 to measure the stack height (measured stack height) of the modeling layer 20L (step S17).

Next, the control unit 15 compares the measured stack height with the target stack height, and adjusts, as necessary, either or both of the movement speed and vibration strength when laying the next layer (step S18).

Next, the control unit 15 determines whether a predetermined termination condition is met (step S19). The predetermined termination condition may be, for example, that all pre-set processes have been executed, that the operator has input an instruction to terminate, or that a predetermined malfunction has occurred. If the termination condition is met (step S19: YES), the control unit 15 terminates the process.

If the termination condition is not met (step S19: NO), the control unit 15 determines whether the number of stacks (after cleaning or replacement if cleaning or replacement was performed previously) has reached a predetermined number or the difference between the measured stack height and the target stack height has reached a predetermined threshold value or more (step S20). If the number of stacks has reached a predetermined number or the difference between the measured stack height and the target stack height has reached a predetermined threshold value or more (step S20: YES), the control unit 15 notifies, for example, that cleaning or replacement of the sieve 11b is necessary. Here, the operator cleans or replaces the sieve 11b, for example, manually (step S21). When cleaning or replacing, for example, the powder material 17 is temporarily removed from the powder container 11, and the sieve 11b is cleaned by airflow from above and below the storage container 11 using an air gun or the like, or the sieve 11b is replaced, or the powder material 17 is not removed from the powder container 11, and the powder container 11 is vibrated by the vibration unit 16 to drop a small amount of the powder material 17 through the sieve 11b to clean the sieve 11b. Note that, if the powder material 17 is removed from the powder container 11 in step S21, the powder material 17 is stored in the powder container 11 and the process proceeds to the next step. If the number of stacks has not reached the predetermined number and the difference between the measured stack height and the target stack height is not equal to or greater than the predetermined threshold value (step S20: NO), or if cleaning or replacement has been performed (step S21), the process returns to step S14 and the processes from step S14 onwards are executed again.

(Action and Effects)
In this embodiment, the powder supply amount can be made uniform by vibrating a powder container equipped with a sieve (mesh) using a vibration unit (oscillator), and a uniform powder layer can be formed along a curved surface, for example. In addition, there is no need to provide a separate blade or the like to flatten the surface of the powder layer. In addition, feedback control of the amount of powder applied allows for modeling according to the design model.

As described above, according to this embodiment, the stack height of the modeling layer 20L formed by the powder material 17 dropped from the powder container 11 is measured by the sensor 14, and at least one of the moving speed of the powder container 11 or the vibration strength of the vibration unit 12 is adjusted based on the measured stack height, which is the stack height measured by the control unit 15, and the target stack height, so that the stack height of the powder material can be appropriately adjusted.

(Modification)
Although an embodiment of the present invention has been described above with reference to the drawings, the specific configuration is not limited to the above embodiment, and also includes design modifications and the like within the scope of the gist of the present invention.

Computer Configuration
FIG. 7 is a schematic block diagram showing the configuration of a computer according to the embodiment.
The computer 90 comprises a processor 91 , a main memory 92 , a storage 93 , and an interface 94 .
The above-mentioned control unit 15 is implemented in a computer 90. The operations of each of the above-mentioned processing units are stored in the form of a program in a storage 93. The processor 91 reads the program from the storage 93, loads it in the main memory 92, and executes the above-mentioned processing in accordance with the program. The processor 91 also secures storage areas in the main memory 92 corresponding to each of the above-mentioned storage units in accordance with the program.

The program may be for realizing some of the functions to be performed by the computer 90. For example, the program may be for realizing the functions by combining with other programs already stored in the storage, or by combining with other programs implemented in other devices. In other embodiments, the computer may include a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device) in addition to or instead of the above configuration. Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array), etc. In this case, some or all of the functions realized by the processor may be realized by the integrated circuit.

Examples of storage 93 include HDD (Hard Disk Drive), SSD (Solid State Drive), magnetic disk, magneto-optical disk, CD-ROM (Compact Disc Read Only Memory), DVD-ROM (Digital Versatile Disc Read Only Memory), semiconductor memory, etc. Storage 93 may be an internal medium directly connected to the bus of computer 90, or an external medium connected to computer 90 via interface 94 or a communication line. In addition, when this program is distributed to computer 90 via a communication line, computer 90 that receives the program may expand the program in main memory 92 and execute the above-mentioned processing. In at least one embodiment, storage 93 is a non-transitory tangible storage medium.

<Additional Notes>
The powder material laying device 10 described in the above embodiment can be understood, for example, as follows.

(1) The powder material laying device 10 according to the first aspect is a device for laying powder material 17 in an additive manufacturing process, and includes a container (powder container 11) for the powder material 17 having an opening 11a for dropping the powder material 17, a vibration unit 12 for applying vibrations to the container, a moving unit 13 for moving the container, a sensor 14 for measuring the stacking height of the modeling layer 20L formed by the powder material 17 dropped from the container, and a control unit 15 for adjusting at least one of the moving speed of the container or the strength of the vibration based on the measured stacking height, which is the measured stacking height, and a target stacking height. According to this aspect and each of the following aspects, the stacking height of the powder material can be appropriately adjusted.

(2) The powder material laying device 10 according to the second aspect is the powder material laying device 10 according to (1), and the opening 11a is provided with a sieve 11b having a mesh size (W) that allows the powder material 17 to fall in a predetermined vibration state. According to this aspect, the powder material 17 can be caused to fall by being in a vibration state.

(3) The powder material laying device 10 according to the third aspect is the powder material laying device 10 according to (2), and the mesh size of the sieve is large enough not to allow the powder material 17 to fall without vibration. According to this aspect, the powder material can be prevented from falling by not applying vibration, so there is no need to provide a special mechanism to stop the falling.

(4) The powder material laying device 10 according to the fourth aspect is the powder material laying device 10 according to (2) or (3), in which the sieve 11b is cleaned or replaced every predetermined number of stacks or when the difference between the measured stack height and the target stack height is equal to or greater than a predetermined threshold value. According to this aspect, the effects of clogging of the sieve can be suppressed.

(5) The powder material laying device 10 according to the fifth aspect is the powder material laying device 10 according to (2) or (3), and when forming the modeling layer 20L, the powder material 17 that has passed through the sieve 11b at least once is placed in the container. According to this aspect, it is possible to reduce the influence of, for example, powder material with poor fluidity or foreign matter of a size that can be sorted out by a sieve.

1...Layered manufacturing device 2...3D laser scanner for manufacturing 10...Powder material laying device 11...Powder container (container)
11a: Opening 11b: Sieve
12, 16... Vibration unit 13... Moving unit 14... Sensor 15... Control unit 17... Powder material 20... Model 20L... Modeling layer W... Mesh openings h1, h2... Stacking height

Claims (7)

1. An apparatus for laying down a powder material in an additive manufacturing process, comprising:
a container for the powder material having an opening for dropping the powder material;
A vibration unit that applies vibration to the container;
A moving unit that moves the container;
a sensor for measuring a stacking height of a modeling layer formed by the powder material dropped from the container; and
A powder material laying device comprising: a control unit that adjusts at least one of the moving speed or vibration strength of the container based on a measured stacking height, which is the measured stacking height, and a target stacking height. The powder material laying device according to claim 1 , wherein the opening is provided with a sieve having an opening size that allows the powder material to fall under a predetermined vibration state. The powder material laying device according to claim 2 , wherein the sieve has an opening size that does not allow the powder material to fall without vibration. The powder material laying device of claim 2 or claim 3, wherein the sieve is cleaned or replaced after every predetermined number of stacks or when the difference between the measured stack height and the target stack height becomes equal to or exceeds a predetermined threshold value. The powder material laying device according to claim 2 or 3, wherein when forming the modeling layer, the powder material that has passed through the sieve at least once is placed in the container. 1. A method for laying down a powder material in an additive manufacturing process, comprising:
a container for the powder material having an opening for dropping the powder material;
A vibration unit that applies vibration to the container;
A moving unit that moves the container;
Using
measuring a stacking height of a modeling layer formed by the powder material dropped from the container;
A step of adjusting at least one of a moving speed or a vibration strength of the container based on a measured stack height, which is the measured stack height, and a target stack height;
A powder material laying method comprising: 1. A program for laying down a powder material in an additive manufacturing process, comprising:
a container for the powder material having an opening for dropping the powder material;
A vibration unit that applies vibration to the container;
A moving unit that moves the container;
Using
measuring a stacking height of a modeling layer formed by the powder material dropped from the container;
A step of adjusting at least one of a moving speed or a vibration strength of the container based on a measured stack height, which is the measured stack height, and a target stack height;
A program that causes a computer to execute the following.

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