KR102590754B1 - Real-time Quality Diagnosis and Remedy Method and Powder Bed Type 3D Printing Device Thereof - Google Patents

Abstract

The present invention relates to a powder bed type 3D printing quality real-time diagnosis and action method and a powder bed type 3D printing device that analyzes and diagnoses printing quality in real time, allowing immediate action when a problem occurs. You can identify quality problems, diagnose lamination quality, determine whether action can be taken in real time on the problem, and then automatically control the problem to be handled immediately if action is possible, thereby reducing the number of defective products and producing improved quality output. It relates to a real-time diagnosis and action method for powder bed type 3D printing quality and a powder bed type 3D printing device.

Description

Real-time diagnosis method and action method for powder bed type 3D printing quality, and corresponding 3D printing device {Real-time Quality Diagnosis and Remedy Method and Powder Bed Type 3D Printing Device Thereof}

The present invention provides a real-time diagnosis and action method for powder bed-type 3D printing quality, which analyzes and diagnoses printing quality in real time in powder bed-type 3D printing, allowing immediate action when a problem occurs; and This relates to a powder bed type 3D printing device.

In general, a powder bed type 3D printer means that electronic information about the 3D shape you want to print, converted into 3D printing language using a program, is input into the output device, and the powder of the material you want to laminate is transferred to the output device using a recoater. Thin layers are laminated in units of lamination thickness, and based on the sliced 2D image corresponding to the layer of the 3D shape to be output, the shape area is created through bonding operations such as spraying binder or irradiating a laser on the shape area. This is a device that produces the final 3D shape by combining powders together.

Powder bed type 3D printers produce output by stacking powder in layers of each thickness and repeating the process of combining the powder in the shape area where the output is formed. Accordingly, due to the nature of lamination equipment that prints in layers, it is appropriate to analyze and diagnose the printing quality in each layer for printing quality control. However, in the case of currently used powder bed type 3D printers, level sensors, etc. It consists of a device that can only perform simple diagnoses such as flatness diagnosis.

Conventional powder bed type 3D printers do not have a separate detection means even if a problem occurs in the process of stacking powder or combining powder in the shape area, so the operator is aware of the problem in the middle of the job and needs to If action is not taken, it will result in producing defective output containing defects within the completed output. Accordingly, problems with the lamination quality of the output due to device failure occur, and although time and resources are consumed to perform printing, the entire output is discarded due to an internal defect, resulting in a waste of time and resources. It's happening a lot.

The present invention was created to solve the above problems, and the purpose of the present invention is to use an image sensing means such as one or more cameras or image sensors in a 3D printing device to obtain an image of the state of the powder layered in a layer unit. , the device extracts images of the state of the bonded surface between powder particles by a bonding means such as a binder or a laser, performs printing quality diagnosis in real time through analysis of each image, and takes action in real time depending on the problem. The aim is to provide a real-time diagnosis and action method for powder bed type 3D printing quality and a powder bed type 3D printing device that can improve 3D output quality by automatically controlling real-time processing of problems.

The real-time diagnosis and action method of powder bed type 3D printing quality of the present invention divides the object into a plurality of layers in the height direction based on the three-dimensional shape information about the object to be stacked and transmits the generated work information to the control unit. A step a) of operating the recoater and the powder bonding device respectively by the control unit according to the work information, and applying and bonding the powder to the build plate for each layer; In one layer, a shape detection means located above the recoater and powder combining device extracts an image of the upper surface of the build plate and transmits it to the control unit, wherein the shape detection means detects the powder by the recoater. The applied recoating area (A) is extracted as a recoating image, and the shape area (B) where the applied powder is bonded by the bonding material and means is extracted together as a shape image, and then transmitted to the control unit. b) step; The control unit compares the image including the recoding image and the shape image received from the shape detection means in the corresponding layer with each included reference image, and determines whether a stacking quality problem of the corresponding layer is determined by the recoater. Step c) of diagnosing whether the problem is caused by or by the powder combining device; Step d) in which the control unit generates an action signal depending on whether a problem occurs, and in step d), when the control unit detects a problem and generates an action signal, the problem occurrence image is the recoding image. and performing a step e) of distinguishing which of the shape images is the problem and determining whether the problem image occurring in at least one image is a problem that can be self-processed. In step e), the control unit determines that the problem is a problem that can be self-processed. When determined, if the problem-generating image is a recoating image, an operation signal is generated and transmitted to the recoater cleaning device that cleans the recoater, and if the problem-generating image is a shape image, a print head cleaning device that cleans the powder combining device. It is characterized by performing step e-1) of generating and transmitting an operation signal to.

At this time, in step b), the shape detection means divides the build plate into a plurality of sections along the direction in which the recoater moves, and extracts images of the sections at predetermined time intervals. .

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At this time, in step c), when the control unit receives the recoding image, step c-1) is performed to compare and determine the recoding image with the reference image included in the control unit.

At this time, step c-1) is characterized by comparing and determining at least one of dents, lack of powder, scratches, insertion of foreign substances, poor flatness, and tilt in the recoating image with the reference image.

In addition, in step b), the control unit radiates light to the build plate, and the shape detection means extracts the illuminated image and transmits it to the control unit. Do it as

At this time, the lighting is characterized by a specific pattern.

In addition, in step c), when the control unit receives the shape image, the control unit transmits the layer 2D image of the object included in the work information as a reference image and compares it with the shape image to determine c- It is characterized by performing step 2).

In addition, if the control unit does not detect a problem in step c), step d) generates an action signal to operate the recoater and powder combining device according to the work information for the next layer. It is characterized by

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In addition, in step e), if the problem discovered is a problem that cannot be self-treated, the control unit generates and transmits an action signal that outputs a signal for the problem to the output means, and step e-2) is performed. do.

In addition, the step b) further includes a step b-0) where the control unit determines whether the received image is a distorted image and corrects the image.

In the powder bed type 3D printing device using the real-time diagnosis and action method of powder bed type 3D printing quality of the present invention, the recoater for applying powder; The powder bonding device for bonding the powder by providing a bonding material and means of at least one of a binder, a laser, and heating to the applied powder; The build plate is movable in an upward and downward direction and is provided below the recoater and powder combining device to place the powder applied by the recoater; The shape detection means located on the upper side of the build plate and extracting an image of the upper surface of the build plate; and a control unit that controls the recoater and powder combining device according to work information on the object to be laminated and receives the image extracted by the shape detection means.

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At this time, when receiving the shape image, the control unit compares the shape image with the layer 2D image of the object included in the work information to determine whether a problem has occurred in the powder combining device.

In addition, the powder bed type 3D printing device further includes lighting for irradiating a predetermined pattern to the build plate, and the control unit, when receiving the recoating image, uses the recoding image and the reference included in the control unit. It is characterized by comparing and judging images to determine whether or not a problem has occurred in the recoater.

The powder bed type 3D printing quality real-time diagnosis and action method and the powder bed type 3D printing device of the present invention having the above configuration are used to determine the quality of powder layer layer-by-layer 3D printing process in which layer-by-layer deposition is performed. By analyzing and diagnosing in real time, it is effective in identifying quality problems in output in real time during the 3D printing process. In addition, it is possible to reduce the number of defective products and manufacture prints of improved quality by diagnosing the lamination quality on a layer-by-layer basis, determining whether the problem can be addressed in real time, and then automatically controlling the problem to be handled immediately if action is possible. This can provide efficiency in product manufacturing.

1 is a perspective view of a 3D printing device according to an embodiment
Figure 2 is a perspective view of a 3D printing device according to another embodiment.
Figure 3 is a conceptual diagram of powder lamination according to a predetermined time
Figure 4 is a perspective view of a 3D printing device further including a lighting device.
5 is a plan view of a 3D printing device further including a lighting device.
Figure 6 is a conceptual diagram of a build plate illuminated by light with a lighting device
Figure 7 is a simplified flowchart of the real-time diagnosis and action method of the present invention
Figure 9 is a detailed flowchart 1 of the real-time diagnosis and action method of the present invention.
Figure 10 is a detailed flowchart 2 of the real-time diagnosis and action method of the present invention

Hereinafter, the technical idea of the present invention will be described in more detail using the attached drawings. Prior to this, the terms or words used in this specification and claims should not be construed as limited to their usual or dictionary meanings, and the inventor should appropriately define the concept of terms in order to explain his or her invention in the best way. It must be interpreted as meaning and concept consistent with the technical idea of the present invention based on the principle of definability.

Accordingly, the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent the entire technical idea of the present invention, so at the time of filing the present application, various alternatives may be used to replace them. It should be understood that variations may exist.

Hereinafter, the technical idea of the present invention will be described in more detail using the attached drawings. The attached drawings are merely examples to illustrate the technical idea of the present invention in more detail, so the technical idea of the present invention is not limited to the form of the attached drawings.

1 and 2, the powder bed type 3D printing device 100 (hereinafter referred to as '3D printing device') of the present invention includes a recoater 110 for applying powder, a binder on the applied powder, and a laser. , a powder combining device (120, 121a, 122b) that combines the powder by providing at least one powder combining material and means during heating, capable of moving in the up and down directions, the recoater 110 and the powder combining device 120 A build plate 130 is provided on the lower side and where the powder applied by the recoater 110 is located, and is located on the upper side of the build plate 130 to extract an image of the upper surface of the build plate 130. A control unit that controls the recoater 110 and the powder combining device 120 according to the sensing means 140 and work information about the object to be laminated, and receives the image extracted by the shape sensing means 140. It is characterized by

1 and 2, if the 3D printing device 100 of the present invention is described in more detail, the recoater 110 is attached to the build plate 130 located below the recoater 110. It is a device for spraying powder and applying the sprayed powder, and is preferably configured to spray powder of uniform thickness evenly on the build plate 130 in the stacking direction. For example, the recoater 110 may be formed with a spray hole through which powder is discharged toward the build plate 130, and the spray hole may have a structure where the powder falls through a gap between long slits. The recoater 100 may be formed to discharge an appropriate amount of powder through the injection hole, or may be formed to apply the powder at intervals of the desired thickness, and the recoater 110 pushes the applied powder. , it can be configured so that powders of uniform thickness are stacked evenly. As another example, the recoater 110 may be composed of a separate supply device and a roller, so that powder is applied on the build plate 130 through the supply device, and the roller is configured to flatten the applied powder.

The recoater 110 may be configured to reciprocate on the build plate 130, and may be configured to move in one direction and discharge powder, or to reciprocate in one direction and the other direction and discharge powder, depending on the user's settings. You can. In one embodiment of the present invention, the recoater 110 may be configured to reciprocate in the longitudinal direction of the build plate 130 and move in one direction to deposit powder on the build plate 130.

When described with reference to FIGS. 1 and 2, the 3D printing device 100 of the present invention may further include a recoater cleaning device 160 capable of cleaning the recoater 110. The recoater cleaning device 160 may be installed on either side of the reciprocating direction of the recoater 110, and cleans the spray port of the recoater 110. In addition, the recoater cleaning device can clean not only the nozzle of the recoater but also a contact surface in contact with the powder layer surface applied on the recoater 110 and the build plate 130, and by cleaning the recoater , it is possible to prevent the problem of foreign substances sticking to the recoater and deteriorating the quality of the laminated surface.

The powder bonding devices (120, 121a, 122b) provide powder bonding materials and means for bonding powder particles to the powder applied by the recoater 110, so that the output is stacked and fixed by bonding the powder particles to each other. The goal is to make it happen. The powder binding device 120 may be selected and used by the user depending on the material of the powder. For example, at least one powder binding material and means may be provided among a binder, a laser, or heating to a temperature above a certain level. It is desirable to configure it to do so. In one embodiment of the present invention, as shown in FIG. 1, the powder combining device 120 may be composed of a print head 121a that sprays a binder, and the print head 121a is used to print the object to be manufactured. By spraying the binder at a position according to the shape of, the powder particles at that position can be combined to form a printout. At this time, in order to deal with problems caused by the binder sprayed by the print head 121a, a print head cleaning device 121b may be further included. In another embodiment of the present invention, as shown in FIG. 2, the powder combining device 120 may be composed of a laser 122a and a scanning system 122b, and the scanning system 122b may provide work information. The angle may be rotated, and the light irradiated by the laser 122a may be configured to irradiate the powder so that the powder particles are combined.

The build plate 130 is preferably positioned below the recoater 110 and the powder combining device 120 and is movable in the vertical direction. The build plate 130 may be located inside the job box 170 that can accommodate the build plate 130, and the job box 170 is detachable from the 3D printing device 100. can be formed. Powder is applied to the upper surface of the build plate 130 by the recoater 110, and a binding material that binds the powder is sprayed onto the powder by the powder binding device 120, so that the object to be manufactured is solidified and laminated. It will happen. At this time, the build plate 130 is characterized in that it descends by the laminated thickness after the lamination of one layer is completed, that is, it is configured to move downward per layer unit. Accordingly, the result may be positioned on the upper surface of the build plate 130 and accommodated inside the job box 170.

The shape detection means 140 is located on the upper side of the build plate 130 and extracts the shape of the upper surface of the build plate 130 as an image and transmits it to the control unit. The shape detection means 140 may be any device capable of extracting an image of a shape. In one embodiment of the present invention, the shape detection means 140 may be a camera or an image sensor, and the recoater ( 110) and the powder combining device 120, it is preferably arranged to photograph the upper surface of the build plate 130. The shape detection means 140 may be provided in one or more pieces to increase the accuracy of image extraction. Depending on the user's settings, each shape detection means 140 may capture separate areas or be located at different locations. It may be configured to photograph the entire area of the build plate 130.

In one embodiment of the present invention, the shape detection means 140 is located above the recoater 110 and the powder combining device 120 and may be configured to photograph the upper surface of the build plate 130, in which case the shape The sensing means 140 may be set to divide the upper surface of the build plate 130 into a plurality of divisions and take pictures at regular time intervals according to each division.

If explained in more detail with reference to FIG. 3, the shape detection means 140 is composed of a plurality, and the build plate 130 is connected to a plurality of shapes along the movement or operation direction of the recoater 110 and the powder combining device 120. It can be divided into sections, and each shape detection means 140 can be set to photograph a designated section. At this time, since the shape detection means 140 is located above the recoater 110 and the powder combining device 120, a portion of a certain compartment may be detected by movement of the recoater 110 or the powder combining device 120. The image can be extracted in this masked state. Accordingly, the plurality of shape detection means 140 may be configured to capture separate sections multiple times at a predetermined time interval (△t), and images captured multiple times are transmitted to the control unit, and the images captured multiple times are transmitted to the control unit. It may be configured to extract unobstructed images of the recoater 110 and the powder combining device 120 through an image processing process in the control unit.

In addition, the shape detection means 140 performs a recoating state in which the powder is applied to the build plate 130 by recoating and bonding between particles of the powder by the powder bonding device 120, solidifies the powder, and stacks the powder. The feature is that the shape state can be extracted by distinguishing regions. If explained in more detail with reference to FIGS. 1 and 2, the shape detection means 140 detects the recoating area (A) where the powder is applied by the recoater 110, and the applied powder to the bonding material and means. The image can be extracted by distinguishing the solidified shape area (B), and is characterized in that it is divided into each recoding image and shape image and transmitted to the control unit. Accordingly, in the present invention, since the control unit can compare and determine each recoating image and shape image with different reference images, when a problem occurs, it is determined whether the problem is caused by the recoater 110 or the powder combining device 120. There is an advantage in being able to distinguish whether the problem is caused by

In addition, when described with reference to FIGS. 4 to 6, the 3D printing device 100 may further include a light 150 positioned to irradiate light to the build plate 130, and in the case of the light 150 It may have a specific pattern, and when the light 150 of the pattern is irradiated to the powder, the powder of the build plate 130 can solve at least one of the problems of dents, lack of powder, scratches, insertion of foreign substances, poor flatness, and tilt. It is characterized by being distinguishable. At this time, the lighting 150 may be provided on the upper side of the build plate 130, perpendicular to the build plate 130, but may be provided at a position biased to one side of the build plate 130. It may be configured to irradiate light to the build plate 130 in a diagonal direction. The illumination 150 may be a visible light illumination, or non-visible light such as infrared light may be used. When the illumination 150 is an invisible light illumination, the shape detection means 140 may receive the corresponding invisible light. It can be configured to easily extract the form of light emitted by the lighting by further providing a filter or sensor. The lighting 150 may be used as a mixture of visible light lighting and invisible light lighting. When explaining with reference to FIG. 6, when the shape detection means 140 extracts an image for the shape area B, the lighting 150 illuminates a specific pattern on the powder-coated build plate 130. The shape detection means 140 may be configured to transmit the extracted image to the control unit, determine that a specific pattern of lighting is broken or distorted, and send it to the recoater 110 device or the powder combining device ( It is possible to determine whether a problem has occurred in the powder combining device 120, and in the case of a problem with the powder combining device 120, it is possible to determine which nozzle from which the binder is sprayed has the problem.

The control unit translates the object to be laminated into 3D printing language, controls the recoater 110 and the powder combining device 120 according to the input work information, and receives the image extracted by the shape detection means 140. It is also characterized in that, among other parts provided in the 3D printing device 100, parts that are connected to transmit and receive signals are controlled. The control unit stores a reference image for comparison with the extracted image. The reference image is one that has been confirmed to be a normal image, and may have been created through an existing operation, or may have been obtained through a separate process before the operation and verified through a separate normal judgment process.

The control unit of the present invention compares and determines the image received from the shape detection means 140 and the reference image to diagnose whether a problem occurs in the quality of powder lamination. At this time, a difference occurs between the received image and the reference image. In this case, it is configured to recognize that a problem with printing quality has occurred.

In more detail, the control unit determines that the image extracted by the shape detection means 140 is a recoding image obtained by extracting the image of the shape area A, and that the image of the shape area B is extracted. Shape images can be distinguished and received. At this time, the control unit may receive a 2D image of the layer for the object from an external device, including the work information, and when the image received by the control unit is the shape image, the 2D image for the corresponding layer may be used as the reference image. It can be configured to diagnose whether a problem has occurred by comparing it with the received shape image. In addition, after the recoater 110 completes the powder application operation, the control unit can control the light 150 of a specific pattern to be irradiated on the applied powder, and the shape detection means 140 can capture an image of the light 150 on the applied powder. You can control image extraction. Accordingly, when the received image is the recoding image, the control unit may be configured to diagnose whether a problem has occurred by comparing and determining the recoding image and the reference image.

Referring to FIG. 7, in the real-time diagnosis and action method of powder bed type 3D printing quality of the present invention using the 3D printing device 100 having the above-mentioned characteristics, the method is based on three-dimensional shape information about the object to be laminated. In this way, the work information generated by dividing the object into a plurality of layers in the height direction is input to the control unit, and the recoater 110 and the powder combining device 120 are moved or operated by the control unit according to the work information. In step a) of applying and combining powder to the build plate 130 for each layer, in any one layer, a shape detection means located on the upper side of the recoater 110 and the powder combining device 120 ( Step b) in which 140) extracts the image of the upper surface of the build plate 130 and transmits it to the control unit, the control unit is in the corresponding layer, the image received from the shape detection means 140, and the image included in the control unit It is characterized in that step c) is performed by comparing and determining the reference image to diagnose whether a stacking quality problem of the corresponding layer occurs, and step d) in which the control unit generates an action signal depending on whether a problem occurs.

In step a), work information about the object to be laminated is input to the control unit, and the control unit operates the recoater 110 and the powder combining device 120 according to the work information to deposit powder on the build plate 130. This is the step of applying and providing a powder bonding material on the applied powder to form a printout by bonding between powder particles. At this time, the recoater 110 and the powder combining device 120 are preferably moved to apply and combine the powder while reciprocating in the longitudinal direction of the build plate 130. After the work for each layer unit is completed, After moving the build plate 130 downward by the stacking unit, the recoater 110 and the powder combining device 120 are operated again and can be controlled to apply and combine the powder. In step a), the recoater 110 and the powder combining device 120 can be controlled to work simultaneously at a predetermined time interval. In step a), in an embodiment of the present invention, The powder combining device 120 is controlled to operate after the work of the recoater 110 is completed.

Step b) is characterized in that the top image of the build plate 130 is extracted for one layer using the shape detection means 140 and transmitted to the control unit. At this time, the shape detection means 140 may be composed of a plurality of pieces and located on the upper side of the recoater 110 and the powder combining device 120, and the recoater 110 and the powder combining device ( 120) is divided into a plurality of sections in the longitudinal direction of the build plate 130 so that the complete shape can be extracted by distinguishing between the shapes of the upper surface of the build plate 130, and the time is varied according to each section. This can be controlled to extract the image. This can be divided into compartments according to the moving speed of the recoater 110 and the powder combining device 120, and according to the time interval when the recoater 110 and the powder combining device 120 are located in each compartment. It may be configured to extract a top image of the build plate 130 by extracting a plurality of images, transmitting them to the control unit, and extracting an image of the complete shape from the plurality of images received from the control unit. In addition, in step b), images can be extracted for each section according to the movement or operation of the recoater 110 and the powder combining device 120, and the images of the extracted portions are respectively transmitted to the control unit, It may be configured to extract the top image of the build plate 130 into images divided into each section.

In step b), the shape detection means 140 detects the recoated area (A) where the powder is applied by the recoater 110 and the shape area (B) where the applied powder is solidified by the binding material and means. Images can be extracted separately. In more detail, the control unit operates the recoater 110 and the powder combining device 120 according to the input work information, and when it recognizes that the operation of the recoater 110 is completed, the shape detection means 140 It can be controlled to extract an image for the recoating area (A), and when it recognizes that the operation of the powder combining device 120 is completed, the shape detection means 140 extracts an image for the shape area (B). Extraction can be controlled. Accordingly, the shape detection means 140 may transmit a recoater image and a shape image to the control unit for each area.

When explained with reference to FIG. 7, step b) may further include step b-0) in which the control unit corrects distortion of the received image. The control unit may include an image distortion correction program, and step b-0) may be configured to automatically correct the distorted image according to the processor of the program when an image is input to the program. Step b-0) may be automatically performed at the same time as step b) is performed by user selection, or may be set to optionally perform step b-0). In addition, step b-0) may be performed including determining whether the image itself is distorted, and the control unit determines whether the image is a distorted image, and if the image received by the control unit is not a distorted image, can be controlled to perform step c).

If explained with reference to FIG. 8, step b) is b-1 in which light with a predetermined pattern is radiated to the powder using the lighting 150 that irradiates light to the upper surface of the build plate 130 according to the user's needs. ) may further include steps. The step b-1) is characterized in that illumination 150 is irradiated to the build plate, and the shape detection means 140 extracts the image illuminated by the illumination 150 and transmits it to the control unit as a reference image. do. At this time, the lighting 150 may use a pattern such as a straight line repeated at regular intervals, which has the advantage of further improving the recognition rate of the quality of the recoated surface.

Step c) compares and determines whether there is a difference between the reference image stored in the control unit and the image received from the shape detection means 140 for the corresponding layer, and determines whether a stacking quality problem occurs in the corresponding layer. This is the diagnosis stage. In more detail, step c) is to diagnose lamination quality problems in the 3D printing device 100 that is laminated layer by layer, and includes a top image of the build plate 130 extracted by the shape detection means 140 and , It is characterized in that the reference image included in the control unit is compared and judged, and if there is a difference, it is recognized as a stacking quality problem.

In the present invention, in step b), the shape detection means 140 can distinguish each of the recoding images and shape images and transmit them to the control unit, and in step c), the images received from each of the shape detection means 140 can be processed separately. At this time, in step c), the control unit may receive input from another device regarding the reference image. For example, the control unit may include converting the object into a 2D image for each layer in the work information, and set this as the reference image. Alternatively, the image captured by the shape detection means 140 may be received as a reference image.

If described in more detail with reference to FIG. 9, in step c), when the control unit receives the recoding image, the control unit may perform step c-1) of comparing the reference image and the recoding image. , it is possible to detect whether a problem with the recoating has occurred through step c-1). The recoating image is an image extracted by a shape detection means for the powder applied to the build plate 130, and through the recoating image, the recoater's dents, lack, scratches, poor flatness, tilt, etc. of the powder are detected. Problems can be discovered, and the present invention is characterized in that the control unit compares and determines at least one of the above problems with a reference image. Additionally, the reference image may be received in a state where the light 140 is not irradiated, or may be received in step b-1). When the image is received with the light 140 illuminated, it is preferable that the image extracted from the upper surface of the build plate 130 is also an image received with the light irradiated. On the other hand, since the applied powder is not easy to distinguish with the naked eye, the present invention radiates light with a predetermined pattern to the powder using a light 150 that radiates light to the upper surface of the build plate 130, and By comparing the results with the coating image, it is easier to diagnose whether a lamination problem has occurred. At this time, the lighting 150 may use a pattern such as a straight line repeated at regular intervals, which has the advantage of further improving the recognition rate of the quality of the recoated surface. Accordingly, in step b-1), when the control unit irradiates light using the lighting 150, the control unit extracts the image as an image through a shape detection means and transmits it to the control unit, and the control unit uses the image as a reference. You can set it as an image. Accordingly, in step c-1), a comparison decision may be made between the reference image received in step b-1) and the recoding image.

In addition, referring to FIG. 9, in step c), when the control unit receives the shape image, the control unit may perform step c-2) in which the control unit compares the shape image with a reference image, Through step c-2), it is possible to detect whether a problem occurs in the powder combining device 120. The shape image is extracted by a shape detection means from the solidification between powder particles by the powder binding material and the resultant layering, and can be visually distinguished. Accordingly, in step c-2), the control unit may set a 2D image per layer of the object included in the work information as a reference image, and compare the reference image with the shape image to determine whether a stacking quality problem occurs. can be diagnosed.

Step d) is characterized in that the control unit generates an action signal according to the diagnosis of whether or not a stacking problem occurs in step c). In step d), if it is diagnosed that a lamination problem has not occurred in step c), the control unit sends an action signal to the recoater 110 and the powder combining device 120 according to the work information for the next layer. ) may be configured to generate and transmit an actuated signal.

As explained with reference to FIG. 10, when it is diagnosed that a stacking problem has occurred in step c), in step d), the control unit performs step e) to determine whether the discovered problem is a problem that can be self-treated. An action signal can be generated. In more detail, step e) determines whether the problem diagnosed in step c) is a self-problem caused by equipment operating in the 3D printing device 100, and the self-problem is a self-problem caused by the 3D printing device 100. It may be about a problem that can be self-managed by control of the control unit within (100). In one embodiment, the problem that can be self-managed is a problem with a defect in the surface of the powder caused by the recoater 110 or a problem with a defect in the surface combined by the powder combining device 120, and the recoater 110 And it may be a problem that can be handled by correcting the powder combining device 120 to a certain extent. At this time, the predetermined correction is to control the recoater 110 to be cleaned immediately using the recoater cleaning device 160 even if the time for the recoater cleaning operation has not arrived, or the powder combining device 120 cleans the binder. In the case of a spraying print head 121a, even if the time for cleaning the print head 121a has not yet arrived, it is controlled to be cleaned immediately using the print head cleaning device 121b, or the powder combining device 120 is controlled to be cleaned using a laser In the case of a device including, the surface temperature of the laser or the output and irradiation pattern of the laser may be corrected according to cause analysis.

When explained with reference to FIG. 10, in step e), the control unit receives at least one or more of the recoding image and the shape image, and at least one or more of the received recoding image and the shape image is Although there is a difference from the reference image included in the control unit, it may be configured to determine whether the problem found in the recoding image and the shape image is a problem that can be handled by control of the control unit and determine that it is a problem that can be self-processed. Additionally, if a problem found in at least one of the recoding image and the shape image is a problem that cannot be handled by control of the control unit, it may be determined that the problem cannot be self-processed. In more detail, there is a difference between the recoding image and the reference image compared and determined by the control unit, and the control unit determines whether the problem of the recoding image received is a problem that can be handled by correction of the recoater 110. It may be. In addition, there is a difference between the shape image compared and determined by the control unit and the reference image, and the control unit determines whether the problem of the shape image received is a problem that can be handled by correction of the powder combining device 120. .

In step e), if it is determined that the problem diagnosed in step c) is a problem that can be self-treated, the control unit performs correction for at least one of the recoater 110 and the powder combining device 120. Characterized in that step e-1) is performed to generate an action signal and transmit it to each recoater 110 and/or powder binding device 120. The action signal generated in step e-1) controls the recoater 110 to be cleaned immediately using the recoater cleaning device 160 even if the recoater cleaning operation time has not arrived, or the powder combination When the device 120 is a print head 121a that sprays a binder, even if the time for cleaning the print head 121a has not arrived, it is controlled to be cleaned immediately using the print head cleaning device 121b, or the powder If the coupling device 120 is a device including a laser, it may be a control signal capable of correcting the surface temperature of the laser or the output and irradiation pattern of the laser according to cause analysis. At this time, in step e-1), an action signal is generated through step e-1) by automatic control immediately after the operation of the recoater 110 and the powder combining device 120 of the corresponding layer is completed. It is desirable to configure it so that it can be processed.

In step e), if it is determined that the problem diagnosed in step c) is a problem that cannot be self-handled, the control unit can record the problem in the equipment log and provide information about the problem to the user in real time through an output means. It is characterized by performing step e-2) of generating a notifiable action signal. In step e-2), when notifying the user, the image received by the control unit may be included and output to the output means. At this time, in step e-2), since the step diagnosed in step c) is a problem that cannot be self-processed, for the quality of the output, the user is asked whether to stop automatically or to stop the printing job immediately. An additional step can be taken to have the control unit directly decide whether to ask or to record only the equipment log and continue, or to send an alarm to the user.

As described above, the present invention has been described with reference to specific details such as specific components and drawings of limited embodiments, but this is only provided to facilitate a more general understanding of the present invention, and the present invention is not limited to the above-mentioned embodiment. No, those skilled in the art can make various modifications and variations from this description.

Accordingly, the spirit of the present invention should not be limited to the described embodiments, and all matters that are equivalent or equivalent to the claims of this patent as well as the claims described below shall fall within the scope of the spirit of the present invention. .

100: 3D printing device
110: Recoater 120: Powder combining device
121a: Printer head 121b: Printer head cleaning device
122a: Laser 122b: Scanning system
130: build plate 140: shape detection means
140: Lighting 150: Recoater cleaning device
170: Job Box

Claims (19)

Based on the three-dimensional shape information about the object to be stacked, the object is divided into a plurality of layers in the height direction and the generated work information is transmitted to the control unit, and the recoater and powder combining device are operated by the control unit according to the work information. Each operates, step a) of applying and bonding powder to the build plate for each layer;
In one layer, a shape detection means located above the recoater and powder combining device extracts an image of the upper surface of the build plate and transmits it to the control unit, wherein the shape detection means detects the powder by the recoater. The applied recoating area (A) is extracted as a recoating image, and the shape area (B) where the applied powder is bonded by the bonding material and means is extracted together as a shape image, and then transmitted to the control unit. b) step;
The control unit compares the image including the recoding image and the shape image received from the shape detection means in the corresponding layer with each included reference image, and determines whether a stacking quality problem of the corresponding layer is determined by the recoater. Step c) of diagnosing whether the problem is caused by or by the powder combining device;
A step d) in which the control unit generates an action signal depending on whether a problem occurs,
In step d), when the control unit detects a problem and generates an action signal, it distinguishes whether the problem occurring image is the recoding image or the shape image, and determines whether the problem occurring image occurring in at least one image is self-generated. Perform step e) to determine whether the problem can be handled,
In step e), if the control unit determines that the problem can be self-processed, an operation signal is generated and transmitted to the recoater cleaning device that cleans the recoater if the problem image is a recoding image, and the problem image is If it is an image, step e-1) is performed to generate and transmit an operation signal to a print head cleaning device that cleans the powder binding device. A real-time diagnosis and action method for powder bed type 3D printing quality.
In paragraph 1:
In step b) above,
The shape detection means is,
Dividing the build plate into a plurality of sections along the direction in which the recoater moves, and extracting images of the sections at predetermined time intervals
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
delete According to clause 1,
In step c), when the control unit receives the recoding image,
Performing step c-1) of comparing and determining the reference image included in the control unit and the recoding image.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
According to clause 4,
In step c-1),
In the recoating image, at least one of dents, lack of powder, scratches, insertion of foreign substances, poor flatness, and tilt is judged by comparison with the reference image.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
According to clause 1,
In step b) above,
The control unit radiates light to the build plate, and the shape detection means extracts the illuminated image and transmits it to the control unit.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
According to clause 6,
The lighting is in a specific pattern
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
According to clause 1,
In step c), when the control unit receives the shape image,
The control unit transmits the layer 2D image of the object included in the work information as a reference image and performs step c-2) of comparing and determining the shape image.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
According to clause 1,
In step c), if the control unit does not detect a problem,
Step d) generates an action signal to operate the recoater and powder combining device according to the operation information for the next layer.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
delete delete According to clause 1,
In step e) above, if the problem discovered is a problem that cannot be handled by yourself,
Step e-2) is performed by the control unit to generate and transmit an action signal that outputs a signal for the problem to the output means.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
In paragraph 1:
In step b),
The control unit further includes a step b-0) of determining whether the received image is a distorted image and correcting the image.
A real-time diagnosis and action method for powder bed type 3D printing quality characterized by .
In the powder bed type 3D printing device using the real-time diagnosis and action method of powder bed type 3D printing quality of claim 1,
The recoater for applying powder;
The powder bonding device for bonding the powder by providing a bonding material and means of at least one of a binder, a laser, and heating to the applied powder;
The build plate is movable in an upward and downward direction and is provided below the recoater and powder combining device to place the powder applied by the recoater;
The shape detection means located on the upper side of the build plate and extracting an image of the upper surface of the build plate; and
The control unit controls the recoater and powder combining device according to work information about the object to be laminated and receives the image extracted by the shape detection means;
A powder bed type 3D printing device comprising a.
delete delete delete According to clause 14,
When the control unit receives the shape image,
Compare and determine the shape image and the layer 2D image of the object included in the work information to determine whether a problem has occurred in the powder combining device.
Powder bed type 3D printing device featuring.
According to clause 14,
The powder bed type 3D printing device further includes lighting that illuminates a predetermined pattern on the build plate,
When receiving the recoating image, the control unit compares the recoding image with a reference image included in the control unit to determine whether a problem has occurred in the recoaster.
Powder bed type 3D printing device featuring.

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