RU2438939C2 - Device to fabricate 3d parts and structures in space - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to space engineering, particularly, to 3D printing by principle of layer-by-layer building-up of solid geometrical figure by electron beam. Proposed device may be used aboard the International space station (ISS). First, 3d objects are formed in vacuum chamber (container) aboard ISS. Then, said chamber is filled with air and dissembled. First platform 17 is secured on ISS outer surface to connected by frames 19 with second platform 16 supporting moving platform 5 with micro motors 3. Wire (powder) 4 feed system, electron beam generator 2 and video control device 12 are mounted on back side of top cover of container 11. All said components are connected with computer 6 to allow astronaut to platform control drives 3 and configuring the entire 3D object. Moving platform 5 allows producing both separate elements of ISS structure, e.g. bars 14, 15 and welding them together. Electron beam is focused on metal source (wire or powder) fed continuously to said beam to melt it above revolving surface and lay layer-by-layer in compliance with 3D object design. Light filters fitted in lens of video control device 12 allows controlling aforesaid process. Besides, data of fabrication process is entered into computer system to be compared with appropriate design, recorded and entered into data base.

EFFECT: expanded operating performances.

3 cl, 2 dwg

Description

The invention relates to means for the manufacture of volumetric parts and structures, in particular to a device for the manufacture of volumetric parts and structures in outer space.

The prior art methods and devices of volumetric (three-dimensional, 3D) printing are known, which are based on the principle of layer-by-layer creation (growing) of a solid geometric figure. These include:

- the method of sterolithography developed by Charles Hall in 1986 (see patent for invention US 575330);

- a laser sintering method patented by Karl Deckard in 1989 and developed in patents of the German company EOS (see publication WO 9629192, patent for inventions US 5908569, US 5876767, etc.) and the corresponding equipment with which plastic ( from polyamides, a metal mold) or a metal product (by technology of burning polystyrene models, direct manufacture, technology of casting using casting molds and cores);

- the inkjet method proposed by Scott Crump and developed in many countries, including Russia (see patents for inventions RU 2333102, RU 2333101, RU 2321603, RU 2306397, RU 295439, etc.);

- a type of inkjet method called PolyJet, developed by Objet Geometries, with about 40 inventions (see patent application US 2009145357, publications WO 2009013751, WO 2008142691, WO 2009125381, etc.).

In the field of space technology, NASA scientists from Langley Research Center, Hampton, have developed methods and devices for the Solid freeform fabrication apparatus and methods (see US patent for invention No. 7,168,935, application dated 08/01/2003 No. 10/637086, patent holder the US government represented by NASA Director) to create volumetric (three-dimensional, 3D) printing in outer space. The experimental device should go to the International Space Station (ISS) for testing.

The method (Electron Beam Freeform Fabrication, EBF3) makes it possible to fabricate ISS structural elements in space from raw materials using an electron beam. The EBF3 method is implemented in a container (vacuum chamber) in which an electron beam is focused on a metal source (wire or powder) continuously supplied to the beam. The latter melts the metal over a rotating surface, laying it in layers in accordance with the 3D model of the object. The process continues until the complete formation of the object.

Figure 1 shows the device according to US patent No. 7,168,935 that implements the EBF3 method, and containing:

1 - container (vacuum chamber) capable of maintaining a vacuum environment;

2 - device for the formation of an electron beam;

3 - microelectric motors for moving the platform in accordance with the 3D model of the object;

4 - wire feed system (powder);

5 - a movable platform on the surface of which a three-dimensional object is manufactured;

6 - a computer system that is part of a device that stores 3D models of objects (database).

Figure 1 also presents the following structural elements:

7 - low voltage lines connecting the computer system 6 with low voltage lines located inside the container 1;

8 - tap to create a vacuum in the container 1;

9 - high voltage power cable, designed to power the electron beam;

10 - three-dimensional object (3D object), structural element.

The container has a straight shape. In addition, the container may

have an ellipsoidal or any arbitrary shape.

A part of the column of the electron beam forming device is inserted into the container to focus the beam and to supply wire (powder) 4 for manufacturing a three-dimensional object 10.

Under the action of the signals coming from the computer system 6 to the electric motors 3, the free movement of the movable platform 5 within the container is ensured in accordance with a predetermined program for manufacturing the object. The design also provides mounting brackets (not shown) that ensure proper orientation of the electron beam and the wire (powder) feed system 4 relative to the zero coordinates of the electric motors 3. A three-dimensional object 10 is formed on the surface of the moving platform 5 by successively converting the feedstock (wire, powder) into a closed container in which a vacuum is created.

In addition to purely scientific tasks, technology has a commercial component.

Once created, a virtual model can be reproduced at any given time using a database of object models. Moreover, since the laying of layers is accompanied by a much smaller amount of waste than the processing of a solid block of material on machines, EBF3 technology is more economical than traditional production technologies.

The disadvantages of the prior art invention include the occurrence of x-rays and radiation at high powers of the electron beam. To reduce the level of harmful radiation, it is necessary to reduce the power of the electron beam, which leads to a decrease in the productivity of the installation. In addition, it is necessary to provide shielding of the installation in the ISS.

The technical result of the invention is to expand the functionality of the application of EBF3 technology in outer space both inside the ISS and on its outer surface.

The technical result is achieved by the fact that inside the ISS the method for producing bulk materials is implemented in a collapsible container, in a vacuum environment. Moreover, after increasing the pressure in the container and eliminating the vacuum medium from the container, some of the parts for working in outer space can be removed and additional equipment installed that ensures the implementation of EBF3 technology in open space. This allows you to increase the power of the electron beam in the manufacture of large parts or the use of the device as a welding machine for manufactured structural elements in space. EBF3 technology is implemented remotely by an astronaut aboard the ISS, and the equipment is located on the outer side of the ISS in outer space, and the electron beam should not be directed towards the ISS.

The block diagram of a device for the manufacture of volumetric parts and structures in outer space (see figure 2) contains the following elements.

2 - device for the formation of an electron beam;

3 - microelectric motors for moving the platform in accordance with the 3D model of the object;

4 - wire feed system (powder);

5 - movable platform, interconnected with microelectric motors 3.

On the platform 5 are placed volumetric parts and structures made in space;

6 - a computer system designed to control the operation of the nodes and mechanisms of the device based on the analysis of 3D models. The signals from the computer system are sent to command decoders located on microelectromotors, a wire feed system, a video control device, an electron beam forming device;

11 - the reverse side of the top cover of the container;

12 - video control device;

13 - wire (powder);

14 - the first bar, three-dimensional object (3D object);

15 - second bar, three-dimensional object (3D object);

16 - welded joint (volume connection of two rods) based on 3 D technology. Moreover, the first bar 14, the second bar 15 and the welded joint 16 form a three-dimensional part assembly;

17 - the first platform, the base of which is fixed on the outer side of the ISS;

18 - the second platform on which microelectromotors 3 are mounted, controlling the mobile platform 5;

19 is one of the elements of the connection, for example a truss connecting the first and second platforms, and providing a rigid structure of the device.

Figure 2 does not show the following elements, also used in the work:

7 - low voltage lines connecting the computer system 6 with low voltage lines located inside the container 1;

9 - high voltage power cable, designed to power the electron beam;

command decoders located on microelectromotors 3, a wire (powder) feed system 4, a video control device 12, an electron beam forming device 2, which decode control commands coming from a computer system 6.

In addition, vacuum equipment is not used, for example, pumps, outlet 8 for creating a vacuum in the container, and the bottom wall of the container 1, used for manufacturing 3D objects on the ISS.

Computer system 6 is located on the ISS to enable the astronaut to control the creation of a three-dimensional product. The computer system additionally contains models of volumetric connections (welding) of typical objects for creating structures in space.

The lower base of the micro-electric motors - 3 is connected to the surface of the second platform 18, connected by connecting elements, such as farms, with the first platform 17, the base of which is connected to the outer surface of the ISS. The upper microelectric motor 3 is connected to a movable platform 5.

The first platform 17 and the second platform 18 are interconnected by connecting elements, for example trusses, which provide a rigid structure of the device in space.

On the reverse side of the top cover of the container 11, connected to the connecting elements - farms 19, are placed: an electron beam forming device 2, a wire (powder) supply system 4 and a video monitoring device 12, which are connected to a computer 6 connected to the microelectromotors 3.

On the mobile platform 5 can be made as separate elements of the structure of the ISS, for example, a bar 14, 15, and also using a welded joint 16 can be connected to these rods.

A device for manufacturing volumetric parts and structures in outer space is assembled on the outer surface of the ISS after completion of the manufacturing of volumetric objects in a vacuum chamber (airtight container) 10 (see Figure 1) inside the ISS. Turn off the vacuum pumps and gradually fill the sealed chamber with air contained in the ISS. After equality of pressure inside and outside the chamber, it is disassembled: microelectromotors 3 are removed with a movable platform 5, and they are installed on the second platform 18.

The first platform 17 is installed and fixed on the outer surface of the ISS, connected to the trusses 19, to which the second platform 18 is mounted with microelectric motors 3 mounted on its surface with a movable platform 5.

The second platform 18 is connected to the first platform 17 using farms 19, providing a rigid connection of nodes and mechanisms. According to one of the farm options, the first platform 17, the second platform 18 and the top cover of the container 11 are connected parallel to each other, and the video monitoring device 12 is located inside the ISS. It is possible to use hardware products of various sizes and purposes. It is also possible to use additional microelectric motors, providing the movement of the second site along the farm. Additional microelectric motors must be equipped with decoders of the commands coming from the computer system 6.

The reverse side of the top cover of the container 11 is placed between the first platform 17 and the movable platform 5 at a distance that provides the optimal technological mode, and fixed on the farms 19. On the surface of the top cover of the container 11 there is a wire (powder) 4 feed system with wire (powder) 13, an electron beam forming device 2, as well as a video monitoring device 12.

The claimed invention is based on the principle of layer-by-layer creation (growing) of a solid geometric figure based on the use of an electron beam that focuses on a metal source (wire or powder) continuously supplied to the beam (electron beam) under vacuum. An electron beam melts metal over a rotating surface, laying it in layers in accordance with the 3D model of the object. The process continues until the complete formation of the object. The 3D printing process can be carried out not only in a vacuum environment of a sealed container installed inside the ISS, but also on its outer surface. An astronaut using a video monitoring device can remotely monitor the implementation of work, with the help of filters inserted into the lens of a video monitoring device, monitor the manufacturing process (connection) of the ISS design elements. In addition, information about the manufactured object is read into a computer system, compared with the corresponding model of the object, recorded and entered into the database. As a result, a decision is made about the possibility of using the fabricated object or structure in the ISS.

Some parts of aircraft, such as aircraft, weighing 130 kg are made from 2720 kg of titanium billets. The present invention will allow to produce similar parts using 160 kg of raw materials, providing significant cost savings.

Future crews of lunar or Martian missions will have the opportunity to create on-site the required spare parts for equipment and tools. The benefits are obvious. Of course, you will have to take metal raw materials with you, but it is likely that suitable material can be extracted from the soil of the planet.

Claims (3)

1. A device for the manufacture of volumetric parts and structures in outer space, containing a device for generating an electron beam, microelectromotors interconnected with a movable platform, on the surface of which a manufactured three-dimensional object is placed, a wire feed system, a computer system, the device for forming an electron beam and a feed system the wires are placed on the back of the upper container lid, characterized in that the first pad is inserted into it, fixed to the outer the surface of the space station, the second platform and trusses connecting the first platform with the second platform, with a video monitoring device additionally placed on the back of the top cover of the container, and the specified cover is placed between the first platform and the second platform at a distance that allows optimal operation of the wire feed device and video monitoring devices, as well as the safe operation of the device for forming an electron beam, while the lower base of the microelectromotors is connected on the surface of the second pad directed toward the space station, and the upper Microelectric attached to the movable platform, the apparatus forming an electron beam wire feed system, and a video control unit connected to the computer micromotors. 2. The device according to claim 1, characterized in that the trusses connect the first platform, the second platform and the top cover of the container parallel to each other. 3. The device according to claim 1, characterized in that the video monitoring device is located inside the international space station.

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