CN113102782A

CN113102782A - Double-camera-based metal 3D printing process monitoring method and printing device

Info

Publication number: CN113102782A
Application number: CN202110500652.1A
Authority: CN
Inventors: 史炜坚; 毛丽; 刘建业; ***
Original assignee: Shanghai Hanbang United 3d Tech Co ltd
Current assignee: Shanghai Hanbang United 3d Tech Co ltd
Priority date: 2021-05-08
Filing date: 2021-05-08
Publication date: 2021-07-13

Abstract

The invention provides a monitoring method and a printing device based on a double-camera metal 3D printing process, wherein the monitoring method comprises the following steps: monitoring the trend condition of the spark during printing by using a camera positioned at an air inlet; monitoring the layer section condition of the part after scanning by using a camera positioned at an air inlet; monitoring the condition of the powder bed after powder spreading is finished by using a camera positioned at an air inlet; and monitoring the smoke condition of the lower air opening by using a camera positioned at the lower air opening. The monitoring method based on the dual-camera metal 3D printing process can realize more comprehensive monitoring of the printing process, and the two cameras adopt the position distribution, so that the cameras positioned at the air inlet can be prevented from being interfered by smoke dust, and the cameras positioned at the air outlet can accurately monitor the related conditions of the smoke dust, thereby ensuring that the monitoring accuracy of the two cameras is higher, namely the monitoring method can more comprehensively and accurately monitor the related conditions in the printing process.

Description

Double-camera-based metal 3D printing process monitoring method and printing device

Technical Field

The invention relates to the technical field of metal 3D printing, in particular to a monitoring method and a printing device based on a dual-camera metal 3D printing process.

Background

With the development of science and technology, people can use 3D printing technology to print and manufacture metal parts. However, in the printing process, external defects caused by powder laying of each layer and laser melting cannot be recorded in real time manually, and the printing process is more difficult to trace after printing is completed, so that waste parts are not easy to find in time, and the printing process is not easy to improve according to the grasped related information in the printing process. In the process of printing and manufacturing metal parts by using a 3D printing technology, if the printing process can be monitored, unqualified products can be found early, the cost and powder consumption can be reduced, and the dependence on analysis after printing can be reduced. Due to technical limitation in the prior art, comprehensive and accurate monitoring of relevant conditions in the 3D printing process is not achieved.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a monitoring method based on dual-camera metal 3D printing process, which can monitor the printing process more comprehensively and more accurately.

In order to achieve the above object, the present invention provides a monitoring method based on dual-camera metal 3D printing process, comprising the steps of:

monitoring the trend condition of the spark during printing by using a camera positioned at an air inlet;

monitoring the layer section condition of the part after scanning by using a camera positioned at an air inlet;

monitoring the condition of the powder bed after powder spreading is finished by using a camera positioned at an air inlet;

and monitoring the smoke condition of the lower air opening by using a camera positioned at the lower air opening.

Further, when printing is performed, a camera located at the air inlet takes a picture for 1 time to monitor the trend condition of the spark.

Further, after the scanning is finished, a camera located at the air inlet shoots for 1 time to monitor the layer section condition of the part after the scanning is finished.

Further, after powder spreading is finished, a camera located at the air inlet shoots for 1 time to monitor the condition of the powder bed after powder spreading is finished.

Furthermore, a camera positioned at the lower air opening has a camera shooting function, and the camera positioned at the lower air opening can dynamically shoot the smoke condition of the lower air opening.

Further, the flow direction of the smoke dust at the downdraft opening is monitored by using a camera located at the downdraft opening.

Further, a camera located at the downdraft opening is used for monitoring the optical signal of the smoke dust at the downdraft opening.

Further, the printing area is illuminated by two illumination devices, and the camera located at the upper air inlet and the camera located at the lower air inlet are both located between the two illumination devices.

As described above, the monitoring method based on the dual-camera metal 3D printing process according to the present invention has the following beneficial effects:

the monitoring method based on the dual-camera metal 3D printing process utilizes the camera located at the upper air port to monitor the trend condition of the spark during printing, the layer section condition of the part after scanning and the condition of the powder bed after powder spreading are finished, and simultaneously utilizes the camera located at the lower air port to monitor the smoke condition of the lower air port, so that the monitoring method can realize more comprehensive monitoring on the printing process so as to obtain more comprehensive information, and the two cameras adopt the position distribution, so that the interference of the smoke on the camera located at the upper air port can be avoided, the related conditions of the smoke can be accurately monitored by the camera located at the lower air port, and the monitoring accuracy of the two cameras is further ensured to be higher, namely the monitoring method can more comprehensively and more accurately monitor the related conditions in the printing process.

Another object of the present invention is to provide a printing apparatus capable of monitoring a printing process more comprehensively and accurately.

In order to achieve the above object, the present invention provides a printing apparatus for implementing the monitoring method based on dual-camera metal 3D printing process, wherein the printing apparatus includes a laser printing assembly, a powder bed, a camera located at an upper air inlet, and a camera located at a lower air inlet.

Furthermore, the printing device also comprises two lighting devices, and the camera positioned at the upper air inlet and the camera positioned at the lower air inlet are both positioned between the two lighting devices.

As described above, the printing apparatus according to the present invention has the following advantageous effects:

the printing device is designed based on the structure and based on the steps of the monitoring method, so that the printing process executed by the laser printing assembly can be monitored more comprehensively and accurately.

Drawings

FIG. 1 is a bottom view of a molding hopper of a printing apparatus in an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a printing apparatus according to an embodiment of the present invention.

Description of the element reference numerals

11 Camera

12 camera

2 parts

3 powder bed

4 Lighting device

41 light tube

51 protective glasses

52 laser

53 reflecting mirror

54 focusing mirror

55 galvanometer

6-base platform

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.

It should be understood that the structures, ratios, sizes, and the like shown in the drawings are only used for matching the disclosure of the present disclosure, and are not used for limiting the conditions of the present disclosure, so that the present disclosure is not limited to the technical essence, and any modifications of the structures, changes of the ratios, or adjustments of the sizes, can still fall within the scope of the present disclosure without affecting the function and the achievable purpose of the present disclosure. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for convenience of description only, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention unless otherwise specified.

As shown in fig. 1 and fig. 2, the present embodiment provides a monitoring method based on dual-camera metal 3D printing process, including the following steps:

monitoring the trend condition of the spark 7 during printing by using a camera 11 positioned at an air inlet;

monitoring the layer section condition of the part 2 after scanning is finished by using a camera 11 positioned at an air inlet;

monitoring the condition of the powder bed 3 after powder spreading is finished by using a camera 11 positioned at an air inlet;

the dust conditions at the downdraft are monitored using a camera 12 located at the downdraft.

The monitoring method based on the dual-camera metal 3D printing process utilizes the camera 11 positioned at the upper air port to monitor the trend condition of the spark 7 during printing, the layer section condition of the part 2 after scanning and the condition of the powder bed 3 after powder spreading are finished, and utilizes the camera 12 positioned at the lower air port to monitor the smoke condition of the lower air port, so that the monitoring method can realize more comprehensive monitoring of the printing process to obtain more comprehensive information, and the two cameras adopt the position distribution to avoid the interference of the smoke on the camera 11 positioned at the upper air port and enable the camera 12 positioned at the lower air port to accurately monitor the related conditions of the smoke, thereby ensuring higher monitoring accuracy of the two cameras, namely the monitoring method can more comprehensively and more accurately monitor the related conditions in the printing process.

Meanwhile, as shown in fig. 1 and fig. 2, the present embodiment provides a printing apparatus for implementing a monitoring method based on a dual-camera metal 3D printing process, where the printing apparatus includes a laser printing assembly, a powder bed 3, a camera 11 located at an upper air inlet, and a camera 12 located at a lower air inlet. The printing device realizes more comprehensive and more accurate monitoring of the printing process executed by the laser printing assembly based on the steps of the monitoring method.

Specifically, when printing is performed, the camera 11 located at the air inlet takes a picture for 1 time to monitor the trend condition of the spark 7, so that whether the trend of the spark 7 is normal in printing can be effectively observed; after scanning is finished, photographing for 1 time by a camera 11 positioned at an air inlet so as to monitor the layer section condition of the part 2 after scanning is finished; after the powder spreading is finished, the camera 11 at the air inlet shoots for 1 time to monitor the condition of the powder bed 3 after the powder spreading is finished. According to the monitoring method, the pixels in the current layer of picture and the previous layer of picture are matched and compared, and the deviation value is a defect or difference existing point.

In this embodiment, the camera 12 located at the lower air inlet has a camera shooting function, and the camera 12 located at the lower air inlet can dynamically shoot the smoke condition at the lower air inlet, that is, the camera 12 located at the lower air inlet can monitor the smoke condition at the lower air inlet in real time. Meanwhile, the monitoring method utilizes the camera 12 positioned at the lower air inlet to monitor the flow direction and the optical signal of the smoke dust at the lower air inlet and record whether the trend of the spark 7 is consistent with the flow direction of the smoke dust. The smoke dust is also mixed with optical signals to be reflected to the plasma and the thermal signal source in the camera 12, and the change of the temperature field around the molten pool of the part 2 can be analyzed through an external computer. Because the smoke and dust is in the lower air duct, the smoke and dust cannot easily blow on the protective glasses 51, so that a clear picture is ensured to be seen by an observer, and the possibility of interference is very low.

In the embodiment, the two cameras are sequentially distributed at intervals along the wind field direction and the left and right direction; the camera 11 located at the upper air inlet is the camera located at the right side in fig. 1, and the camera 12 located at the lower air inlet is the camera located at the left side in fig. 1. And the upper air inlet and the lower air inlet are respectively positioned at two sides of the printing area. In addition, fig. 1 is a bottom view of the forming chamber of the printing apparatus in this embodiment. The monitoring method does not simply capture the two laser sources through the two cameras respectively, and better observes the influence caused by each tiny change in the whole 3D printing process through a 'dynamic and static combination' mode.

As shown in fig. 1, the printing apparatus of this embodiment further includes two lighting devices 4 spaced apart from each other in the front-back direction, and the camera 11 located at the upper air inlet and the camera 12 located at the lower air inlet are both located between the two lighting devices 4. The monitoring method illuminates the printing area with two illumination devices 4. The mode can better observe the shape of the powder bed 3 of the upper air channel and the lower air channel, and can effectively inhibit visual errors caused by light rays and placement angles. In this embodiment, the lighting device 4 specifically uses a lamp 41. The two lamp tubes 41 are respectively designed on the front side and the rear side of the equipment, so that the camera is not easily subjected to the interference of light rays in the same direction and the visual error caused by the surface reflection of the metal part 2.

As shown in fig. 2, the printing apparatus in this embodiment includes two sets of laser printing components to improve printing efficiency and the like. The monitoring method and the printing device based on the double-camera metal 3D printing process relate to the technical field of metal 3D printing, and are a method and a device for applying process control and quality tracking to a double-laser double-camera 3D printer in a combined manner. The laser printing assembly in this embodiment includes a laser 52, a mirror 53, a focusing mirror 54, and a galvanometer 55. In this embodiment, both the two cameras employ high-speed cameras. The laser 52 is a device for emitting laser, the reflecting mirror 53 is an optical element for totally reflecting incident light, the focusing mirror 54 is a device for focusing a plurality of divergent light sources into a specific spot size, the vibrating mirror 55 is a device for scanning and moving the laser according to a set path, and the camera is a device for photographing a focal plane process.

The specific working principle of the printing device in this embodiment is as follows:

laser light sources emitted by the lasers 52 on the two sides respectively pass through the reflecting mirror 53, the focusing mirror 54, the vibrating mirror 55, the protective mirror 51 and the base platform 6 in sequence and finally reach the plane of the powder bed 3; laser and the metal powder reaction shaping on the powder bed 3, two cameras are located wind gap and wind gap position down respectively according to the wind field direction, come 3 form of observation powder bed and characteristic defect constantly through high-speed camera, and the defect includes: powder spreading uniformity, workpiece warping deformation, holes, cracks and the like; the camera shoots in real time, three pictures are respectively shot after powder laying of each layer is finished, printing is carried out, scanning is finished, and the video file and the picture file are completely transmitted to the equipment server so as to be checked.

In conclusion, the present invention effectively overcomes various disadvantages of the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims

1. A monitoring method based on a dual-camera metal 3D printing process is characterized by comprising the following steps:

monitoring the trend condition of the spark (7) during printing by using a camera (11) positioned at an air inlet;

monitoring the layer section condition of the part (2) after scanning is finished by using a camera (11) positioned at an air inlet;

monitoring the condition of the powder bed (3) after powder spreading is finished by using a camera (11) positioned at an air inlet;

and monitoring the smoke condition of the lower air inlet by using a camera (12) positioned at the lower air inlet.

2. The monitoring method based on dual camera metal 3D printing process as claimed in claim 1, wherein the camera (11) located at the air inlet takes 1 picture to monitor the orientation of the spark (7) while the printing is in progress.

3. The monitoring method based on the dual-camera metal 3D printing process is characterized in that after the scanning is finished, the camera (11) positioned at the air inlet shoots for 1 time to monitor the layer section condition of the part (2) after the scanning is finished.

4. The monitoring method based on the dual-camera metal 3D printing process is characterized in that after the powder spreading is finished, a camera (11) positioned at an air inlet takes a picture for 1 time to monitor the condition of the powder bed (3) after the powder spreading is finished.

5. The monitoring method based on the dual-camera metal 3D printing process is characterized in that a camera (12) positioned at the lower air opening has a camera shooting function, and the camera (12) positioned at the lower air opening can dynamically shoot the smoke condition of the lower air opening.

6. The dual camera metal based 3D printing process monitoring method as claimed in claim 1, wherein the flow direction of the soot at the downdraft is monitored by a camera (12) located at the downdraft.

7. The dual camera metal based 3D printing process monitoring method as claimed in claim 1, wherein the optical signal of the smoke of the downdraft is monitored by a camera (12) located at the downdraft.

8. The dual camera metal based 3D printing process monitoring method as claimed in claim 1, characterized in that the printing area is illuminated by two illumination devices (4), and the camera (11) located at the uptake and the camera (12) located at the uptake are both located between the two illumination devices (4).

9. Printing device for implementing the dual camera based 3D printing process monitoring method according to claim 1, wherein the printing device comprises a laser printing assembly, a powder bed (3), a camera (11) located at the upper air inlet and a camera (12) located at the lower air inlet.

10. Printing device according to claim 9, further comprising two lighting devices (4), the camera (11) located at the uptake and the camera (12) located at the uptake being located between the two lighting devices (4).