Additive manufacturing equipment for parts

Abstract

According to the invention, an apparatus for additive manufacturing of a part, preferably by selective melting or sintering, in particular by a powder bed based laser beam melting process, is provided, which apparatus comprises a control unit. Modules of the additive manufacturing apparatus for the part can be exchanged without further setup steps, so that the additive manufacturing apparatus for the part can be quickly reconfigured. The invention also provides a planning control unit for automatically generating a production process plan for manufacturing a specific part by said additive manufacturing apparatus.

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for additive or generative manufacturing of parts. [Background technology]

[0002] US Patent No. 5,399,633 describes an apparatus and method for generative part manufacturing using several spatially separated beam guides. A processing head has several light switching elements capable of directing several beams to a target location. The processing head can be moved along a linear axis. The linear axis is slidably mounted on a perpendicular linear axis. This allows for XY movement. A laser beam source is mounted on the linear axis.

[0003] Patent document 2 discloses an additive manufacturing device by selective laser sintering. One or more lasers are assigned to one or more laser heads. These lasers are distributed to the individual heads via beam splitters. The heads can be moved in the X and Y directions along rails. The heads can be moved independently of each other. The light supply to the heads is realized by mirrors.

[0004] US Patent No. 5,399,633 describes an additive manufacturing process in which an optical head is fed with a laser beam via an optical fiber, which allows several laser beams to be directed to the same head and emitted from it in parallel, which allows for parallel melting points on the surface of the powder bed.

[0005] A similar process is described in US Pat. No. 5,399,633.

[0006] US Patent Nos. 5, 6 and 7 disclose selective laser sintering devices with several optical heads that can direct a laser beam onto the powder bed. These heads themselves cannot be moved in the X and Y directions, but instead can direct the laser beam to the corresponding position via mirrors. The advantage of this is that the laser focus can be moved quickly. However, the heads must be relatively far away from the powder bed and can only illuminate a limited area.

[0007] Nos. 5,399,410, 5,443,502 and 5,596,623 show an apparatus for sintering with a cross-slide configuration, an additive manufacturing process with several heads for plastic printing, and an apparatus equipped with a head having both a 3D printer and a 3D cutting element.

[0008] US Patent No. 5,399,633 discloses an apparatus and method for selective laser melting, in which multiple laser heads are provided operating in parallel to melt material according to a powder bed based laser melting process. Each laser head is movable along a linear rail unit, and the laser heads are movable independently of each other. The array of laser heads and the powder bed surface can be rotated horizontally relative to each other.

[0009] US Patent No. 5,399,633 describes an apparatus and method for additive manufacturing of parts, the apparatus comprising several robot arms, on each of which a deposition head and a laser head are mounted adjacent to each other. Each of the robot arms comprises at least one pivot joint and is designed to move the deposition head and the laser head in all three spatial directions. In this way, material can be applied to the treatment surface by the deposition head and this area can be melted immediately afterwards by the laser.

[0010] US Pat. No. 5,399,433 discloses an apparatus including equipment for additive manufacturing and milling processes. The apparatus essentially comprises several robotic arms, which may be equipped with gripper elements for providing material on a work platform or for removing finished components, or with a laser head. The robotic arms each comprise two joints and are thus mounted so that they can be rotated and swiveled. The apparatus also comprises a central production arm, which may be equipped with a laser head or a milling head. The central production arm can move linearly along a rail unit.

[0011] Patent document 14 features an additive molding device in which two laser heads are provided that operate in parallel to melt the material according to the additive molding process. Both laser heads are coupled to a rail unit and can move linearly independently of each other. The rail unit can also move. This allows a complete coverage of the treatment area. The laser beam is directed to the treatment area by a focusing unit that uses two mirror elements.

[0012] US Patent No. 5,399,633 describes an apparatus and method for 3D printing, in which a laser for melting a starting material and a cutting laser for processing the manufactured structure are provided, the laser for melting the starting material and the cutting laser can move both horizontally and vertically independently of each other along several rail units. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] DE 102016222068 A1 [Patent Document 2] International Publication No. 2018 / 202643 [Patent Document 3] U.S. Pat. No. 10,399,183 [Patent Document 4] U.S. Patent No. 10,399,145 [Patent Document 5] US Patent Application Publication No. 2015 / 0283612 [Patent Document 6] US Patent Application Publication No. 2014 / 0198365 [Patent Document 7] JP 2009-6509 A [Patent Document 8] German Patent No. 10053742 [Patent Document 9] U.S. Pat. No. 9,011,136 [Patent Document 10] China Utility Model No. 206065685 [Patent Document 11] US Patent Application Publication No. 2019 / 0009333 [Patent Document 12] US Patent Application Publication No. 2017 / 0129012 [Patent Document 13] China Patent Application Publication No. 106312574 [Patent Document 14] DE 102018128543 [Patent Document 15] DE 102022107263 Summary of the Invention [Problem to be solved by the invention]

[0014] It is an object of the present invention to provide an apparatus and method for additive manufacturing of parts, preferably by selective melting or sintering, that can be flexibly adapted to parts of different dimensions.

[0015] It is a further object of the present invention to provide an apparatus and method for additive manufacturing of parts that is simple in design, allows for high production rates, and is capable of producing 3D parts with high accuracy.

[0016] One or more of these problems are solved by a device having the features of the independent claim 1 and by a method having the features of claim 15. Advantageous embodiments are given in the dependent claims. [Means for solving the problem]

[0017] According to the invention, an apparatus for additive manufacturing of parts, preferably by selective melting or sintering, is provided, which comprises at least one module having a processing head for directing a light beam to a processing area, a swivel arm on which the processing head is arranged and a carriage on which the swivel arm is rotatably mounted, the module being movable along a rail unit, the control unit being capable of storing module parameters defining predetermined properties of the module, the control unit being configured and designed to control different modules using the module parameters, so that modules can be exchanged in the apparatus for additive manufacturing of parts, which can be controlled by the control unit, preferably without further configuration steps.

[0018] The control unit is configured and designed to control different modules based on the module parameters so that modules can be replaced with other modules as needed, or modules can be removed or added to change the configuration of the additive manufacturing apparatus so that the apparatus can be converted and adapted accordingly, for example to produce a large number of parts, or to produce parts in the shortest possible time, or to produce parts of high quality.

[0019] Because the module parameters are stored or can be stored within the control unit, the control unit can control different modules and corresponding different configurations of an additive manufacturing device having different interchangeable modules such that despite these changes the device can control different modules or configurations of the additive manufacturing device.

[0020] Thus, the device according to the invention can be adapted as desired or nearly as desired to different numbers of parts to be produced as well as to different requirements regarding production times and quality such as porosity or surface quality, etc. In principle, the configuration should be optimized in such a way that a large number of treatment heads and / or very powerful treatment heads are provided in areas where a lot of material is applied.

[0021] The device according to the invention can therefore also be adapted to the geometry, in particular to the material accumulation and the corresponding size of the surface or treatment area of ​​the part to be additively manufactured.

[0022] In this way, the device according to the invention is extremely flexible and can be adapted, within certain limits, to almost any production requirement.

[0023] These different configurations allow significantly higher throughputs, since each individual configuration of the additive manufacturing machine can be optimized for throughput. Conventional additive manufacturing machines, especially those with a process head that is movable by several carriages, cannot be individually configured for the parts to be manufactured, and therefore have excess capacity in areas where little material is applied and insufficient capacity in areas where more material is applied.

[0024] This will be explained in more detail below with reference to the technical features of the device according to the invention.

[0025] The module is Processing head, A pivoting arm having a processing head; a carriage with one pivot arm and processing head or with several pivot arms and processing heads, or A rail with one or more carriages and one pivot arm and processing head or a rail with several pivot arms and processing heads It can be provided with:

[0026] Additionally, the following settings on your additive manufacturing machine: Rail units at different positions within the processing chamber, in particular at different distances from each other; Different rail units, Different types of carriages, Different types of swivel arms, especially with regard to the degrees of freedom and / or length of the arms, A different number of processing heads per rail unit, in particular a corresponding number of swivel arms and carriages, Different types of processing heads, One or more of the can be changed by replacing one or more modules; The control unit is configured and designed to control these components, so that the machine can be converted accordingly for producing different parts and / or different areas of the part.

[0027] Furthermore, the module may have an internal or external identifier. An external identifier is an identifier that is read by an external reader used when installing the module. An internal identifier is an identifier that is automatically read by a reader integrated into the additive manufacturing device. An internal identifier may be in the form of, for example, a barcode or an RFID chip or a type designation stored in a semiconductor memory. An external identifier may be in the form of, for example, a barcode or an RFID chip, etc. The identifier comprises either a module parameter or a code that can be automatically assigned to a module parameter, and the corresponding module parameter can be automatically loaded into the control unit or the module parameter can be automatically selected if the module parameter is already present.

[0028] Different module parameters for different modules may be stored in the device and the module parameters may be provided internally or externally, for example using an internal or external database, online or in association with the module itself, etc.

[0029] By providing identifiers corresponding to the modules, the machine knows which module is currently installed and what characteristics it has (e.g., the length of the pivot arm, or the transverse or linear acceleration of the carriage, or the rotational acceleration and / or rotational speed of the pivot arm) in order to convert the machine into different configurations or different arrangements and / or numbers of modules according to the processing requirements of the parts being manufactured.

[0030] The module parameters include, for example, information about the length of the pivot arm, information about the light intensity or temperature of the processing head, in particular the processing head for melt application, and / or information about the transverse speed or transverse acceleration of the carriage, as well as information about possible arrangements of the rail units at different heights perpendicular to the build platform in the Z direction, or about the distance between two rails parallel to the surface of the build platform in the X or Y direction.

[0031] The control unit may comprise two components: The control unit is a production control unit that controls the production process planning of the 3D printer or additive manufacturing device of the part.

[0032] Another component of the control unit is a planning control unit, which creates one or more production process plans and / or one or more configurations for the 3D printer.

[0033] According to a further aspect of the invention there is provided a planning control unit for automatically generating a production process plan for manufacturing a particular part by an additive manufacturing apparatus for a part, in particular by said additive manufacturing apparatus for a part.

[0034] The planning control unit is configured and designed to generate at least one manufacturing process on the basis of CAD data or a build plan of the part to be manufactured, said planning control unit being characterized by the fact that it is configured and designed in such a way that it is able to generate several production process plans for which different configurations of the additive manufacturing device for the part are used with different module parameters, whereby one of the production process plans can be selected with respect to the parameters production time and / or quality.

[0035] This means that the planning control unit is able to analyze the CAD data or the building plan (Bauplan) of the part to be manufactured. Based on this analysis, the configuration of the additive manufacturing machine can then be adapted by specifying certain modules.

[0036] Thus, the planning control unit can analyze the part to be manufactured and output an optimal configuration in order to automatically generate a production process plan for manufacturing the particular part using an additive manufacturing device for the part.

[0037] Additionally and / or alternatively, the planning control unit can also create several production processes with different configurations of modules based on the CAD data and then automatically select the production process. The configuration used here is preselected by validation, since a precise analysis is sometimes very time-consuming and different production processes with different configurations also show different advantages, so it is not possible to state generally which configuration and which production process is best. This depends on the specific application. The materials used can also be varied, which provides further freedom in the analysis and optimization. The production process plan can also be selected manually based on the created production process plan.

[0038] For automatic selection, the planning control unit can also be configured and designed to automatically select a production process plan according to predefined parameters.

[0039] For example, short production times can be advantageous for applications when there are large volumes or high machine utilization rates, especially if high demands are not placed on the quality of the parts produced. This means that modules with several or many processing heads and / or long or short pivoting arms can be provided. Furthermore, processing heads with different light intensities or powers or generating different temperatures in the powder bed can also be provided in order to melt larger or smaller processing areas.

[0040] In principle, a slow carriage movement speed and a short pivot arm allow in particular to produce a high product quality, whereas a long pivot arm and a fast movement speed allow a low product quality.

[0041] The planning control unit can also store which modules are available in the device to determine which module configurations are possible.

[0042] In this way it can be clearly determined which module and which number of modules or which module configuration is best suited for manufacturing the part.

[0043] The module parameters are: Different numbers, and / or Different types of pivot arms, especially with regard to length and / or pivot range, and Different types and positioning of rail units in the processing chamber, in particular with respect to the X-direction or Y-direction parallel to the build platform, preferably with respect to the Z-direction and therefore with respect to the height perpendicular to the build platform, and / or Different types of carriages, in particular with regard to structural design or geometric shape or movement speed, and / or different types of processing heads, in particular with regard to light intensity output or temperature, and / or Different number of processing heads per rail unit may include.

[0044] Furthermore, different control parameters, including different movement speeds or accelerations of the carriage and the swivel arm and / or different printing speeds of the processing head and / or different intensities or temperatures, can be stored in the control unit, in particular in the production control unit or planning control unit, which can be automatically and / or manually selected based on the components used, in particular the modules of the apparatus, and / or based on the building plan of the part and / or based on multiple production process plans or based on one production process plan.

[0045] In particular, modules with a greater number of carriages per rail unit may be provided with processing heads having shorter pivot arms and modules with a smaller number of carriages per rail unit with longer pivot arms.

[0046] Preferably, two or more rail units may be provided such that they can be moved together, in particular parallel to the build platform and / or perpendicular to the build platform.

[0047] This means, for example, that for areas or levels of parts with large processing areas, the rail units can be spaced further apart parallel to the build platform and then moved closer together in areas with a larger accumulation of material or a higher part density parallel to the build platform in order to position more processing heads in that particular area.

[0048] The rail units are also movable in height in the Z direction perpendicular to the build platform, so that corresponding pivot arms of adjacent modules are positioned one above the other in the Z direction and do not collide when moving. To avoid collisions between the pivot arms of adjacent carriages, the pivot arms can also be positioned on the carriages at different heights.

[0049] In a preferred embodiment, the length of the swivel arm of the module can be changed automatically by an adjustment unit, for example by a linear drive, which can be performed only during pauses, for example when the configuration of the additive manufacturing device is changed, or can also be changed during normal operation.

[0050] Such automatic changes can be made automatically for different layers, and individual configurations are also defined for each layer or group of layers when the production process plan is created, so long as this can be changed automatically.

[0051] The modules can also be exchanged automatically: for this purpose they can be stored in a module magazine and exchanged automatically using an exchange robot.

[0052] Automatic changeover can also be achieved in combination with automatic adjustment of the length of the pivot arm or automatic exchange of modules, or alternatively, by automatically moving the rail on which the carriage is mounted.

[0053] By adjusting the length of the swivel arm, for example, a long swivel arm can be changed to a short one during operation (dynamic), thus preventing the swivel arms of the processing heads or modules from touching each other when two rail units of adjacent modules are placed closer to each other. A short swivel arm can only cover a smaller area around the rail (coverage area). However, a shorter swivel arm allows more accurate positioning compared to a longer swivel arm. Furthermore, at least two or more rails to which a short swivel arm is attached can be placed very close to each other, providing a high density of processing heads.

[0054] According to the above embodiment, different numbers of modules can be arranged at given locations within the device.

[0055] The modules can be connected to a power and control unit, preferably to a light source, via a coupling unit. The apparatus can comprise a process chamber, one or more build platforms and at least one material supply unit.

[0056] The apparatus can have a processing chamber, one or more build platforms, and at least one material supply unit.

[0057] Furthermore, at least one distance sensor may be provided, preferably measuring electro-optical distance, to optically monitor the position of the processing head in the X and / or Y directions parallel to the build platform and / or in the Z direction perpendicular to the build platform.

[0058] This ensures that adjacent process heads do not come into contact with each other during processing, thus safely and reliably avoiding damage to components of the apparatus.

[0059] Furthermore, according to the present invention, there is provided a method for calculating an optimal configuration of an additive manufacturing device for a part, in particular the device disclosed above. Such a method comprises: Retrieving CAD data for a part to be manufactured; determining local work requirements for each layer; determining an optimal configuration according to the processing requirements of all layers of the part to be manufactured; Includes.

[0060] Thus, according to the present invention, a simple method is provided in which only the CAD data is read and an optimal module configuration is determined according to the processing requirements of all layers based on the CAD data.

[0061] In this way, the user only needs to retrieve the CAD plan, which automatically outputs the modules that must be equipped on the machine in order to manufacture parts with an optimal module configuration in terms of quality and / or processing time and / or quantity. The machine can then be easily converted accordingly.

[0062] The optimal configuration is: Allocating multiple processing heads to a print area having a large accumulation of material, and / or Allocating short pivot arms to printing areas with large accumulations of material, in particular to allow the arrangement of several processing heads in this area, and / or Allocating a small number of processing heads to a printing area having a small surface area, and / or Allocating a long pivot arm to a printing area with a small surface area This can be achieved by:

[0063] With the processing head located on a shorter pivot arm, parts of greater precision and therefore of higher quality can be produced in this area.

[0064] Additionally, processing heads having shorter pivot arms can be positioned more densely above a corresponding processing region or above corresponding processing regions.

[0065] On the other hand, a processing head with a longer pivot arm allows a larger range of movement relative to the build platform, which typically results in inferior product quality because the processing head with a long pivot arm cannot be controlled as precisely.

[0066] Thus, by providing a processing head with a longer pivot arm, a larger processing area of ​​the build platform can be covered, so that fewer processing heads are required to manufacture a part.

[0067] Furthermore, according to the invention, a method for additively manufacturing a part, preferably by selective melting or sintering, is provided, in particular using an apparatus as described above, said method comprising the steps of: storing module parameters defining predetermined characteristics of the module within the control unit; controlling different modules by the control unit based on the module parameters, without requiring any further configuration steps; Includes.

[0068] The advantages of this method are similar to those discussed above with reference to the additive manufacturing apparatus for the part.

[0069] Further according to the invention there is provided a method for generating a production process plan for manufacturing a particular part by a planning control unit of an additive manufacturing apparatus for the part, the method comprising: inputting CAD data of the part to be manufactured; generating at least one production process plan using an optimization system based on CAD data of the part to be manufactured; defining different configurations of modules of an additive manufacturing device for the part, and based on this creating one or more production process plans, the production process plans being based on different module parameters of the additive manufacturing device; selecting a production process plan based on production time or throughput and / or product quality, the production process plan and the appropriate or determined configuration being output; Includes.

[0070] The advantages of this method are similar to those described above with reference to the planning control unit according to the invention.

[0071] Additionally, different configurations can result in changes in modules and therefore coating speeds in particular areas based on changes in the placement or location of the processing heads and their assigned processing areas, and / or changes in the number of processing heads in different areas.

[0072] This may for example mean an arrangement of processing heads and the processing areas assigned thereto. This may also mean a different number or density of processing heads in different areas. Furthermore, completely different module configurations and thus different numbers and different arrangements and / or the provision of other modules may also be provided. Furthermore, according to the invention, an apparatus for additive or generative manufacturing of parts according to further embodiments is provided, preferably by selective melting or sintering, in particular by a powder bed based laser beam fusion process (LPBF: Laser Powder Bed Fusion) with a control unit. This apparatus also operates according to the principles of the invention described above.

[0073] The apparatus includes a plurality of processing heads for directing a light beam onto a processing area, the processing heads being each disposed on a pivoting arm, the pivoting arm being disposed on a carriage movable along a rail unit.

[0074] The invention is particularly characterized in that the control unit is arranged and designed to control the device, for which purpose: rail units at different locations within the processing chamber; and / or Different rail units, and / or Different types of carriages, and / or different types of swivel arms, in particular with regard to the degrees of freedom and / or length of the arms, and / or a different number of processing heads per rail unit, in particular with a corresponding number of pivot arms and carriages, and / or Different types of processing heads so that the device can be converted to produce different parts and / or different areas of a part. is used.

[0075] The fact that the control unit is configured and designed to be able to control different parts of the apparatus therefore provides an additive manufacturing apparatus that can be adapted depending on the geometry, in particular the material deposit and the corresponding size of the surface of the part to be additively manufactured.

[0076] In this way, the device according to the invention is extremely flexible and can be adapted, within certain limits, to components of almost any size and design.

[0077] In the context of the present invention, different types of pivot arms are understood to mean that the arms may have different degrees of freedom and / or different lengths, the degrees of freedom in particular relating to the pivot radius or the pivot angle range of the pivot arm.

[0078] Further, the apparatus may have a light source for generating a light beam, and one or more processing heads may be either coupled to the light source with a beam guide such that the light beam is guided to the processing head, or the light source may be located directly on the processing head such that the light beam may be directed from the processing head to the processing area, whereby the processing head may be movably mounted such that the light beam may be directed to different points within the processing area.

[0079] The processing head can be designed as a print head or a smoothing head.

[0080] In the context of the present invention, additive manufacturing methods are understood to mean the layer-by-layer construction of three-dimensional parts using powder beds, powder feeders or wire feeders that act as starting materials and are melted by a laser beam, an electron beam or a plasma or an electric arc. Thus, the generative manufacturing methods mentioned in the introduction of this specification (3D printing: melting and solidification (as laser engineered net shaping (LENS), direct metal deposition (DMD) or as laser additive manufacturing (LAM)), local sintering or melting (selective laser sintering (SLS)), metal laser sintering (DMLS), metal laser sintering (IMLS), electron beam melting (EBM), powder bed based laser beam fusion laser bed fusion (LPBF) or laser cladding) are used to carry out the method according to the invention.

[0081] According to a preferred embodiment of the invention, a rail unit having two or more carriages and one processing head per carriage forms a module, and different numbers of modules can be positioned at predetermined positions in corresponding module holders in the processing area.

[0082] By providing corresponding module holders, the density of modules can be increased or decreased depending on the size of the part and / or the material accumulation of the part in a particular area so that the corresponding parts can be additively manufactured quickly, efficiently, and with high quality.

[0083] The module holder may have holders for holding rail units, the rail units being preferably positioned on either diametrical side of the processing area.

[0084] The fact that a corresponding holder is provided for holding the rail unit means that the corresponding module can be easily inserted or coupled to the device and can be easily removed as well.

[0085] In principle, the modules of the device can be exchanged manually, the holders can have, for example, quick action clamping units for fixing the modules, etc. Alternatively, however, the modules can also be exchanged automatically using a robot arm or exchange robot, especially if the device is used in larger production lines and if parts of different dimensions are manufactured during ongoing production.

[0086] The rail units are preferably all of the same type or essentially the same type. This means that the rail units can be arranged in the module holders or corresponding holders respectively and flexibly exchanged. This can also be advantageous in series production, for example, if the modules or corresponding parts of the modules are only partially functional or no longer functional.

[0087] Preferably, two or four carriages can be arranged on the rail unit, however, it is also possible within the scope of the invention to arrange at least two, three or four, or even at most five, six, seven, eight, nine or ten processing heads on the rail unit.

[0088] The holders of the module holder can be arranged at the same distance from each other. Preferably, they are arranged at fixed positions in the device. According to an alternative embodiment, two or more module holders can also be arranged on the corresponding traversing unit in order to move two or more modules individually or together.

[0089] The distance between two adjacent module holders is about 5cm or at least 4cm or 5cm or 6cm and at most 7cm or 8cm or 9cm or 10cm or 15cm or 20cm or 25cm or 30cm.

[0090] Thus, the modules can be positioned in the module holder with equal and / or different spacing.

[0091] The rail units or modules are preferably spaced so that the cover areas overlap adjacent rail units.

[0092] Furthermore, the modules may be exchangeable, with different modules having different processing heads and / or different numbers of processing heads and carriages being held in a magazine, the modules may thus be held in a kind of tool exchange unit, which may preferably be exchanged manually as already mentioned above, but may also be exchanged automatically, for example by a robotic unit.

[0093] Modules with a higher number of carriages can be provided with processing heads having shorter pivot arms and modules with a lower number of carriages with longer pivot arms.

[0094] In this way, more carriages with corresponding processing heads can be provided in areas of the parts being manufactured having a larger accumulation of material and / or a larger part surface without the corresponding pivot arms interfering with each other or forming overlapping pivot areas.

[0095] A coupling unit may also be provided on the module, preferably on a corresponding module holder, via which the module is connected to a power supply and control unit and preferably to at least one light source.

[0096] One or more laser devices or light sources can be provided to generate laser beams for all the processing heads. The laser devices can then be connected to each individual processing head, for example, by means of light guides. In this case, possibly corresponding power lines with data lines can be arranged in the rail unit or the rail unit can be formed so that the rail unit can also be used for the transport of electricity.

[0097] Alternatively, a corresponding laser device may be located directly on each processing head.

[0098] Different movement speeds of the carriage and / or the swivel arm and / or different printing speeds and / or different temperatures of the processing head can be stored in the control unit and these can be automatically and / or manually selected based on the components used, in particular the modules of the apparatus, and / or based on the build plan of the parts to be manufactured.

[0099] In this way, the device according to the invention can be variably adapted to parts of different dimensions and is flexible in its application area.

[0100] Furthermore, the control unit can be configured and designed to use the building plans for the different parts to select which components, particularly modules of the device, are required for production and then display them accordingly.

[0101] In particular, at least one distance sensor may be provided, preferably for electro-optical distance measurement, to optically monitor the position of the carriage and / or the pivot arm and / or the processing head, as will be explained in more detail below.

[0102] The apparatus can have at least one processing chamber, at least one build platform, and at least one material supply unit.

[0103] The material supply unit is preferably a corresponding supply unit for a powder bed process, for example a supply cylinder with a coating device (scraper). Alternatively, a wire feeder can also be provided.

[0104] Further in accordance with the present invention, there is provided a method for calculating an optimal configuration for a printing device, the method comprising: A step of reading out part data; determining local work requirements at individual layers and determining an optimal configuration according to processing requirements for all layers or layers of the additively manufactured part; Includes.

[0105] An optimal configuration is understood to be a configuration for forming a part based on its geometry or material accumulation.

[0106] The method according to the invention makes it possible to determine the local work requirements in the individual layers using the part data. An optimal configuration can then be selected according to the processing requirements of all layers or corresponding structures, in particular with respect to the components of the device, in order to form the component as efficiently as possible. Appropriate modules are then selected in order to manufacture the component as quickly, safely, reliably and with high quality as possible.

[0107] The optimal configuration is: Allocating multiple processing heads to a print area having a large accumulation of material, and / or Placing a short pivot arm in a print area with a large buildup of material; and / or Allocating multiple processing heads to a printing area having a large surface area, and / or Allocating a short pivot arm to a printing area with a large surface area This can be achieved by:

[0108] The processing heads can be positioned on one of the carriages by means of pivot arms which are each pivotable about a vertical pivot axis.

[0109] By providing several processing heads, several light beams can be directed simultaneously at the processing area so that several points in the processing area can be melted or sintered in parallel. The processing heads are arranged on a carriage and can move along a traverse or rail unit. This allows a convenient and reliable positioning of the processing heads over the processing area.

[0110] Preferably, the processing heads are each arranged on one of the carriages by means of a pivotable pivot arm. By providing the processing heads arranged on the respective carriages with such a pivot arm, preferably pivoting about a vertical pivot axis, the processing heads can be rapidly positioned at any desired position on a wide section of the processing area. This section extends around the rail unit, along which the respective carriages with the respective processing heads can be moved in an area around the pivot axis of the pivot arm that extends on both sides by a width corresponding to the length of the pivot arm. This section is therefore strip-shaped around the rail unit with a width corresponding approximately to twice the length of the pivot arm. This strip-shaped section is referred to below as the covered area, since the processing heads arranged on the carriages of the rail units can be arranged at any position within the covered area, and therefore the processing area can be illuminated or covered with a light beam at any position within the covered area.

[0111] The pivoting arm can be designed to pivot only around a vertical axis. Such a design is very simple compared to multi-axis robot arms. Nevertheless, the processing heads can be positioned very quickly and precisely, and a high throughput can be achieved thanks to parallel processing.

[0112] The pivoting arm may for example have a length of at least 5 cm, preferably at least 10 cm or at least 15 cm, in particular at least 20 cm. The longer the pivoting arm, the greater the coverage area.

[0113] Since the more the processing head is pivoted away from the pivot arm, the less accurate the position of the processing head in a direction parallel to the rail unit becomes, it may be desirable to position the processing head only within a limited angular range of the pivot arm. The angular range may be limited, for example, to a maximum pivot angle of 60° or 45° relative to the rail unit. At a maximum pivot angle of 45°, the width of the coverage area is reduced to the length of the pivot arm.

[0114] Along the pivoting arms, the beam guides for the respective light beams can be designed using reflector elements, which allows for a very light pivoting arm with a low rotational moment of inertia and therefore can be quickly pivoted to any rotational position.

[0115] The pivot arm is preferably made of plastic, in particular fibre reinforced plastic.The pivot arm may be provided with a mirror at each end remote from the pivot axis for directing the respective light beam towards the treatment area.

[0116] The beam guides can be designed at least partially as light guides. The light guides can extend from the light source to the respective processing head. However, each light guide may be guided only from the light source to the pivot end of the respective pivot arm and arranged there with its end such that the light beam is coupled into the beam guide along the pivot arm formed by the reflector element. Such a design has the advantage that the pivot arm can be rotated 360° or more without the need to rotate the light guide. The end of the light guide, where the light is coupled from the light guide into the beam guide on the pivot arm, can be arranged in a fixed position relative to the carriage on which the pivot arm is mounted.

[0117] Alternatively, the ends of the light guides can be arranged at fixed positions on the pivoting arms such that the light beams are emitted towards, and preferably parallel to, the free ends of the pivoting arms, which can be provided with reflector elements, such as deflecting mirrors, to direct the respective light beams towards the treatment area.

[0118] The reflector element can be a parabolic mirror or a mirror with a freeform surface to focus the light, so that no optical lens is required in the beam path.

[0119] The rail unit, to which the carriage is movably mounted, can be arranged in a fixed position via the holder of the module holder. This is particularly advantageous in connection with a design with a processing head arranged on a swivel arm, since such a fixed arrangement is much easier to control to avoid collisions between the different swivel arms than in a device in which the swivel arm can be swiveled, the carriage can be moved along the rail unit, and the rail unit itself can be moved transversely to the longitudinal direction of the rail unit. Furthermore, the fixed arrangement of the rail unit and the swivel arm on the carriage allows a complete coverage of the machining area to be achieved with only a few rail units, as long as the swivel arm is not too short. The processing head, which is arranged at the free end of the swivel arm, can be very light, for example with only a small mirror, so that a low rotational moment of inertia can be realized even with longer swivel arms, for example with a length of at least 10 cm, preferably at least 15 cm, in particular at least 20 cm.

[0120] Preferably, at least two independently movable carriages are mounted on each rail unit, each carriage carrying a processing head, although there may be more than two carriages per rail unit, for example three or four.

[0121] Preferably, several light sources are provided, each assigned to one or more processing heads. The light sources are preferably lasers, in particular CO2 lasers or ND:YAG lasers. CO2 lasers are mainly used to melt or sinter plastic powders, and ND:YAG lasers to melt or sinter metal powders. CO2 lasers of this kind have an optical power of 30W to 70W, ND:YAG lasers 100W to 1000W or more. The light sources may be light-emitting diodes, in particular superluminescent light-emitting diodes, and / or semiconductor lasers.

[0122] By providing several light sources and several processing heads that can be positioned independently of each other in the processing area, it is possible to melt or sinter the powder at several points in the processing area simultaneously to produce a 3D part. This simultaneous melting or sintering of the powder significantly increases the production rate of production manufacturing with the present device compared to conventional devices. High production rates can be achieved even if the processing heads dwell slightly longer at each individual point. This allows the use of light sources with a relatively low light output. This allows the cost of the device to be significantly reduced.

[0123] A multiplexer can be provided to distribute the light beam of one of the light sources to the different beam guides. Such a multiplexer is preferably useful for very powerful light sources that can melt or sinter powders with short pulses. The apparatus preferably has a powder bed in the processing area, in which powder can be placed, and which is selectively melted by the light beam.

[0124] The powder may be a metal powder or a plastic powder.

[0125] The individual pivot arms may be positioned at different heights to avoid collisions when moving the pivot arms.

[0126] The individual light sources can be designed to emit light beams with different frequencies or ranges of frequencies and / or different intensities, which allows the selective melting or sintering process to be individually controlled, which also makes it possible, for example, to control the porosity of the product thus produced.

[0127] The light beam can also be focused to different degrees on the treatment area, the focusing being adjustable, for example, by adjusting the height of the lens and / or the treatment head.

[0128] In the device according to the invention, the powder can be melted or sintered simultaneously at several points in the powder bed.

[0129] An inert gas atmosphere, particularly a nitrogen and / or argon atmosphere, can be formed throughout the apparatus. The inert gas atmosphere can be used to prevent oxidation of the powder or parts during part manufacture. The formation and maintenance of the inert gas atmosphere can conveniently filter dust from the inside of the apparatus.

[0130] Preferably, an optical system, in particular a zoom optical system, is provided to change the focus of the emitted light beam, which can be easily adapted to different distances from the treatment area, and at the same time, the energy input and the irradiation area can be changed by adjusting the focus.

[0131] According to a further aspect of the invention, at least one distance sensor is provided, preferably for electro-optical distance measurement. The distance sensor can be arranged on or on the moving component to measure the distance to another object or between the sensor and another object. However, it is also possible to arrange the distance sensor on the other object to measure the distance to the moving component. In this way, the distance between the moving component and another object can be measured and determined at any time. The data recorded by the distance sensor is processed accordingly by the control unit according to the invention.

[0132] The distance sensor is preferably arranged at a fixed position to measure the distance between the sensor and the movable component. In this way, the distance between the fixed point and the movable component can be measured and determined at any time. The movable component can have a reference object, and the distance sensor detects the reference object and measures the distance to the reference object. For example, a reflector, in particular a prism reflector, can be used as the reference object. The distance sensor can be pivoted so that it can be aligned with the reference object.

[0133] Distance can be measured by triangulation and / or by measuring the phase position and / or by measuring the travel time. When measuring distance by measuring the phase position, a laser beam is emitted. The phase shift of the reflected laser beam or its modulation with respect to the emitted beam depends on the distance. This phase shift can be measured and used to determine the travel distance. Distance measurement by measuring the phase shift is very accurate. In laser triangulation, a light beam is focused on the measurement object and observed with a camera, a spatially resolved photodiode or a CCD line placed next to it in the sensor. If the measurement object changes its distance from the sensor, the angle at which the light spot is observed also changes and therefore the position of its image on the receiver. The distance of the object from the laser projector is calculated from the change in position using an angular function. Distance measurement using triangulation is simple, inexpensive and very accurate. When measuring the travel time, a light pulse or a modulated light beam is emitted. The travel time is the time it takes for the light beam to travel from the source to a reflector, usually a retroreflector, and back to the source again. By measuring this travel time, the distance between the light source and the object can be determined using the speed of light. Alternatively or additionally, sensors that can scan lines or surfaces or planes or perform spatial measurements, such as stereo cameras for three-dimensional localization of one or more objects, can also be used to measure distance. Such sensors do not need to swivel because their receiving area is large.

[0134] Instead of optical sensors, other sensors may also be used, such as ultrasonic sensors or sensors that use the time of flight of radio waves to determine distance.

[0135] The control and regulating device can thus be designed such that the movable component can be moved to a target position depending on the measured distance between the distance sensor and the movable component. The use of the distance sensor together with the control and regulating device allows the use of a cost-effective and particularly lightweight movement device for moving the movable component or carriage. A cost-effective and lightweight movement device has a lower positioning accuracy but can be moved particularly quickly. The position of the movable component can be controlled depending on the distance between the movable component and the distance sensor. The closer the movable component is to its target position, the slower the component can be moved. In this way, it can be ensured that the movable component can reach the target position accurately. The movement device is simple, particularly lightweight and can be designed advantageously, since the accuracy of the movement and positioning is guaranteed by the distance measurement and the closed-loop control. Proportional controllers, so-called P-controllers, proportional-integral controllers, so-called PI-controllers, and / or proportional-integral-derivative controllers, so-called PID-controllers, can be used as controllers in the control loop.

[0136] Two, preferably three, distance sensors may be provided to measure the distance between the distance sensors and the movable component to determine the spatial position of the movable component. If the movable component is moved only in one plane, i.e. in two dimensions, its position can be accurately determined by measuring the distance from two distance sensors. By measuring three distances between the movable component and three fixed distance sensors, the spatial position of the movable component can be accurately determined in three dimensions. If the movable component is moved only in one direction, one sensor may also be sufficient for distance measurement.

[0137] In a preferred embodiment, more than three distance sensors and at least two moving components are provided, so that each moving component can be detected at any position by at least three distance sensors for distance measurement. The distance sensors can be used to measure the distance between itself and both moving components. Depending on the position of the first moving component, the distance sensor may be hidden by this first moving component, making distance measurement to the second moving component impossible. In such a case, the distance measurement can be performed via another distance sensor that has direct optical access to the second moving component. This makes it possible to use different or even the same distance sensors for each position determination of the moving components by distance measurement.

[0138] The distance sensor can be located at a fixed position in the device or can be connected to the base of the device, for example, via a carrier. The distance sensor can use a distance measurement to determine the position of the surface of the powder bed and then use another distance measurement to determine the position of a movable component, such as a processing head. Depending on the position of the powder bed, i.e. the height of the powder bed, the processing head can be moved to a target position to set the required distance between the processing head and the surface of the powder bed. One or more processing heads can be moved to their target positions using the control and adjustment device described above. It is also possible that one or more distance sensors are connected to or located on the processing head to determine the distance between the processing head and the surface of the powder bed and then to move the processing head to a target distance from the surface of the powder bed.

[0139] Instead of the position of one or more processing heads, the position of another component in the direction of movement, such as a rail unit or a carriage, can also be determined and positioned relative to the surface of the powder bed. For this purpose, one or more distance sensors can be directly connected to the rail unit and measure the distance to the surface of the powder bed.

[0140] The scraper can also be positioned in the same way, for example relative to the powder bed surface. For this purpose, at least one distance sensor can be connected to the scraper or can be arranged at a fixed position in the device.

[0141] The three distance sensors can be permanently assigned to each moving component for distance measurements. The same three distance sensors can be assigned to the same moving component for each distance measurement. However, it is also possible to reassign the distance sensors to the components for each distance measurement. In this way, a different distance sensor can be partially or completely assigned to each moving component for each new distance measurement other than the previous one.

[0142] The above-described embodiments of the present invention may be combined with each other as necessary. The above-described aspects of the present invention are not limited to the combinations of the inventive features specified by the selected paragraph formats.

[0143] Further features of the invention will become apparent from the following description of the invention with reference to the drawings and figures, in which: All the features described and / or illustrated form the subject of the invention, either individually or in any combination, regardless of their summary in the claims or their relationship to one another. [Brief description of the drawings]

[0144] The invention is explained in more detail below with reference to exemplary embodiments shown in the drawings.

[0145] [Figure 1] FIG. 1 is a schematic side view of an additive manufacturing apparatus according to the present invention. [Diagram 2] FIG. 1 is a schematic top view of an additive manufacturing apparatus. [Diagram 3] 1 illustrates a schematic flow diagram of a process for creating a production process plan. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0146] According to an exemplary embodiment, an apparatus for additive manufacturing of a part is provided, referred to simply as a "3D printer" 1. The 3D printer 1 comprises an enclosed processing chamber 2.

[0147] Within the treatment chamber 2 a production unit 3 and a storage unit 4 are arranged adjacent to each other.

[0148] The storage unit 4 comprises a supply receptacle 5 in which the powder 6 is contained. A bottom wall 7 of the supply receptacle can be moved vertically by a supply piston-cylinder unit 8. In this way, the powder 6 contained in the supply receptacle can be transported vertically upwards.

[0149] The production unit 3 comprises a build platform 9. The build platform 9 can also be moved vertically by a production piston-cylinder unit 10.

[0150] Furthermore, the 3D printer 1 has a scraper 11 with which the powder 6 can be applied from the storage unit 4 in a horizontal direction 23 onto the build platform 9 of the production unit 3. In this way, a powder bed 12 can be formed on the build platform 9.

[0151] In the area of ​​the build platform 9, in this design example, three modules 13 are arranged parallel to one another in a top view.

[0152] Such a module 13 comprises a rail unit 14 and several carriages 15 with corresponding processing heads 16 which are connected to the carriages via pivot arms 17 .

[0153] The module 13 is fixed via a corresponding module holder 18. To fix the module 13 to the module holder 18, the module holder has a corresponding holder 19.

[0154] The carriage 15 has a drive unit (not shown) that allows the carriage 15, and thus the processing head 16, to be moved along the longitudinal direction 20 of the rail unit.

[0155] The carriage 15 and the processing head 16 are connected to a control unit 22 via a coupling unit 21 .

[0156] The control unit 22 can store different movement speeds of the carriage 15 and / or the swivel arm 16, and / or different printing speeds and / or different temperatures of the processing head 17, which can be automatically and / or manually selected based on the components used, in particular the modules 13 of the apparatus 1, and / or based on the build plan for the parts to be manufactured.

[0157] Furthermore, the control unit can be configured and designed to use the building plans for the different parts to select which components, particularly modules of the device, are required for production and then display them accordingly.

[0158] The control unit 22 comprises two components: a production control unit 24 that controls the production process planning by the 3D printer 1, and a planning control unit 25 that creates one or more production progress plans and / or one or more configurations of the 3D printer 1.

[0159] The planning control unit 25 executes the procedure for creating a production process plan (FIG. 3) starting from step S1.

[0160] In step S2, a construction plan of the shape of the CAD data is read out.

[0161] In step S3, the build plan is divided into layers corresponding to layers from which the part can be produced in the 3D printer 1.

[0162] In step S4, continuous material regions containing material from the part are determined in the individual layers. Closely adjacent material regions can be combined into a common material region. This combination of material regions within a layer is performed using a cluster method, which is why these combined material regions can also be called layer clusters.

[0163] In step S5, a sintering step by a specific processing head 16 is assigned to each point of the material area. This assignment is performed according to a predefined rule, preferably several adjacent processing points are processed in succession. These rules can be based on different processing principles, such as the one from the unpublished patent application 15, where the material is sintered line by line, the lines are initially made at a certain distance from each other, and after a certain time, the areas between the lines sintered at a certain distance are also sintered, if this corresponds to the build plan. When all material points of all layers have been assigned a sintering processing step, the production route plan is finished and the process ends in step S6.

[0164] The method described above can be modified according to the invention such that after step S4, step S4a is performed, whereby each continuous material region or layer cluster is assigned a value corresponding to the amount of material contained therein, which is proportional to the number of sintering steps required to create this region. The sintering step is the application of laser light for a certain or cycle time. The application can also be continuous, with each application duration relative to the cycle time representing a separate sintering step.

[0165] Thus, the individual regions can be assigned a requirement for a sintering process step, which is a type of optimization weight that indicates whether the respective region should be assigned more or less processing heads 16. These optimization weights are calculated for each layer and assigned to a particular material region or layer cluster.

[0166] In step S4b, the overlapped material regions or layer clusters are clustered in the vertical direction (=Z direction), and the individual overlapped material regions or layer clusters do not need to match exactly. The optimization weights are averaged for the individual clusters, so that the requirements for processing the head 16 can then be assigned to the respective cluster regions based on the averaged optimization weights.

[0167] In step S4c, an optimized configuration of the 3D printer is calculated based on the respective requirements assigned to the clusters, with the numbers of processing heads 16 being distributed as evenly as possible in proportion to the averaged optimization weights.

[0168] The following steps S5 and S6 are executed with this configuration.

[0169] Other optimization methods may also be used to determine the optimal configuration according to steps S4a to S4c.

[0170] In a further variant of the invention, several groups of layers are clustered separately and then within the groups of layers an individual optimal configuration of the 3D printer is determined. Such an optimization of several groups of layers is particularly useful if the configuration of the 3D printer 1 can be performed automatically, for example by the rail unit 14 being automatically movable and / or the length of the swivel arm 17 being automatically adjustable and / or the modules being automatically interchangeable. When executing a production run plan, this results in the 3D printer 1 printing groups of layers each in a specific configuration, and the printing process is briefly interrupted after each group of layers in order to change the configuration, for example by moving the rail unit according to the new configuration and / or by automatically adjusting the length of the swivel arm and / or by automatically or manually exchanging the modules.

[0171] In a further alternative embodiment, an individual configuration can be provided for each layer, i.e. the position of the rail unit 14 and / or the length of the pivot arm 17 can be changed for each layer. In this embodiment, the change in the position of the rail unit 14 and the change in the length of the pivot arm 17 can also be considered an integral part of the change in the position of the process head 16 in the process chamber 2 above the powder bed 12.

[0172] The production control unit 24 controls the production process according to a specified production process plan, where, as basically known from 3D printing, the component is built up layer by layer and one or more laser beams are directed by the process head 16 onto the powder bed 12 in order to melt the powder 6 contained therein. According to the production process plan, it controls the movement of the process head 16 and the switching on and off of the corresponding lasers as well as the application of the powder layers in the powder bed 12.

[0173] If the 3D printer 1 is configured automatically, this is also controlled by the production control unit 24. In this case, the rail unit 14 can be moved automatically and / or the length of the swivel arm 17 can be changed automatically and / or the modules 13, which are preferably stored in a module magazine (not shown), can be exchanged automatically.

[0174] For exchanging the modules 13 , a corresponding exchange robot can be provided, in which case the modules 13 preferably each comprise a carriage 15 with a swivel arm 17 and a processing head 16 .

[0175] The module 13 is designed so that it can be easily detached from the rail unit 14 by an exchange robot and replaced by another module 13 coupled to the rail unit 14. The position of the replaced module 13 is calibrated, for example, by moving the module 13 on the corresponding rail unit 14 to an end position where the module 13 abuts against a predetermined stop.

[0176] Furthermore, according to the invention, a method for additively manufacturing a part, preferably by selective melting or sintering, is provided, in particular using an apparatus as described above, said method comprising the steps of: storing module parameters defining predetermined characteristics of the module within the control unit; controlling different modules by the control unit based on the module parameters without further configuration procedures; Includes.

[0177] Additionally, in accordance with the present invention, there is provided a method for generating a production process plan for manufacturing a particular part by a planning control unit of an additive manufacturing apparatus for the part, the method comprising: inputting CAD data of the part to be manufactured; generating at least one production process plan using an optimization system based on CAD data of the part to be manufactured; defining different configurations of modules of an additive manufacturing device for the part, and based on this creating a plurality of production process plans, where production process plans for different module parameters of an additive manufacturing unit are defined; selecting a production process plan based on production time and / or product quality and / or quantity, where the production process plan and appropriate configuration are output; Includes.

[0178] Furthermore, different configurations may result in changes in components, particularly modules, changes in application speeds per region, which in turn may result in changes in the arrangement or position of the processing heads and their assigned processing regions, and / or changes in the number of processing heads in different regions.

[0179] This may mean, for example, the arrangement of the print buttons of the processing heads and the processing areas assigned to them. It may also mean that the number or density of print heads in different areas is different. In addition, completely different module configurations and thus different numbers and different arrangements and / or the provision of other modules may also be provided.

[0180] Further in accordance with the present invention, there is provided a method for calculating an optimal configuration for a printing device, the method comprising: A step of reading out part data; determining local work requirements at individual layers and determining an optimal configuration according to processing requirements for all layers or layers of the additively manufactured part; Includes.

[0181] An optimal configuration is understood to be a configuration based on its geometry or material accumulation to form a part.

[0182] The method according to the invention makes it possible to determine the local work requirements in the individual layers using the part data. An optimal configuration can then be selected according to the processing requirements of all layers or corresponding structures, in particular with regard to the components of the device, in order to form the part as efficiently as possible. Suitable modules are then selected in order to be able to manufacture the part as quickly, safely, reliably and with high quality as possible.

[0183] The optimal configuration is: Allocating multiple processing heads to a print area having a large accumulation of material, and / or Placing a short pivot arm in a print area with a large buildup of material; and / or Allocating multiple processing heads to a printing area having a large surface area, and / or Allocating short pivot arms to printing areas with large surface areas; This is achieved by:

[0184] Further advantageous embodiments of the invention are given below.

[0185] The rail units 14 are arranged parallel to each other. In this design example, three rail units 14 are provided (FIGS. 1 and 2). The central rail unit 14 is arranged slightly higher than the two outer rail units 14.

[0186] The carriages 15 are controlled by a control unit and can be moved automatically along the respective rail units 14 by means of a drive unit. The drive unit may comprise a drive belt driven by an external motor connected to the respective carriage 15. However, the carriages 15 themselves may also be provided with a drive mechanism, such as a drive wheel driven by a motor. In principle, it is also possible to drive the carriages by a linear motor.

[0187] The pivot arm 16 is arranged on the carriage 15 by a pivot joint. The pivot arm 16 is rotatably mounted on the pivot joint, preferably about a vertical pivot axis. The carriage 15 is provided with a stepper motor for rotating the pivot arm 16 about the pivot axis. A processing head 17 is provided at the end of the pivot arm 16 remote from the pivot axis.

[0188] This is formed by one end of a light guide and an optical lens arranged at that end of the light guide. The processing head 17 is arranged so that the light beam guided in the light guide is emitted vertically downward.

[0189] The light guide is made of a flexible optical fiber, which may be, for example, a glass fiber or an optical polymer fiber.

[0190] The light guide leads to a light source arranged at a distance from the pivot arm 18. The light source is preferably a laser, in particular a CO2 laser or a ND:YAG laser or a fiber laser. The light source may also be a semiconductor laser or a light emitting diode, in particular a superluminescent light emitting diode.

[0191] An array of light sources may also be provided, with one light source for each processing head.

[0192] Further embodiments of the pivot arm are described below and are designed in the same way as the above embodiments unless otherwise stated.

[0193] In an alternative embodiment of the pivot arm 16, the light source, together with an optical lens, is located directly at the end of the pivot arm 17, away from the pivot axis, so that the light beam can be emitted vertically downwards.

[0194] According to a further embodiment, the beam guide is formed from the light source by a light guide to the carriage 15 along the pivoting arm 16 by reflector elements. In this exemplary embodiment, the reflector elements are each designed as a mirror. However, the reflector elements can also be represented by other optical elements which deflect the light beam bundle, such as a prism.

[0195] The pivot joint has a through opening or through hole extending vertically. Adjacent to the upper end of the through hole, the end of the light guide 26 remote from the light source is arranged with a coupling lens, so that the light beam generated by the light source is transmitted through the light guide and is coupled from there into the through hole of the pivot joint. A first reflector element is arranged below the through hole and deflects the light beam so that it is directed towards the free end of the pivot arm. A second reflector element is arranged at the free end of the pivot arm away from the pivot axis and deflects the light beam vertically downwards. Optionally, an optical lens for focusing the light beam can be provided in the beam path between the end of the light guide arranged adjacent to the pivot joint and the second reflector element. Instead of the optical lens 30, an objective lens can also be provided, which allows the degree of focusing of the light beam to be changed.

[0196] The first and / or second reflector element can be shaped, for example as a parabolic or freeform mirror, to focus the reflected light, which means that no optical lens needs to be placed in the light path, or an optical lens with low refractive power can be provided in the light path.

[0197] When moving the processing head 17 by means of the pivoting arm 16, the light guide only moves along the rail unit 14 with its end located in the carriage 15. The pivoting arm 16 can perform rotational movements that do not affect the position of the light guide. This makes it possible for the pivoting arm 16 to perform one or more complete rotations without impairing the function of the light guide, since the pivoting arm is not entrained during such rotational movements of the pivoting arm.

[0198] Such an arrangement allows for a number of processing heads 17 to be provided by a pivoting arm on a carriage 15 movable along the rail unit 14, ensuring that the individual light guides do not intertwine with one another. This makes it easy to make a 3D printer 1 with at least 8, preferably at least 12, in particular at least 16 processing heads, all of which can be exposed to the light beam bundle simultaneously or substantially simultaneously.

[0199] The light source can generate a light beam bundle in continuous mode (cw) or in pulsed mode (pw). In the case of a pulsed light source 25 with high light intensity, it may also be expedient to assign the light source to several processing heads and then a multiplexer is arranged between the light source and the respective processing head, so that the light beam generated by the light source is fed unambiguously to one of several processing heads by the multiplexer. Since the change between the individual processing heads can occur very quickly, compared to melting or sintering processes, the change is so fast that the individual processing heads 13 coupled thereto can be considered to be exposed to the light beam substantially simultaneously.

[0200] A further embodiment of the pivoting arm has as light source an excitation laser with an optical pump and a resonator, which are connected to each other via a light guide 34. The resonator comprises an active medium, preferably made of a solid, which is excited or pumped by the pumping light emitted by the optical pump.

[0201] The resonator together with the optical lens is placed directly at the end of the pivoting arm 17 away from the pivot axis so that the light beam can be emitted vertically downwards. The optical pump is placed on a carriage so that it does not follow the pivoting movement of the pivoting arm. The optical pump usually comprises one or more semiconductor lasers and a heat sink with cooling fins. The optical pump is much heavier than the resonator and the optical lens. The rotational moment of inertia of the pivoting arm 16 is small, since only the resonator and the optical lens are moved, not the optical pump 3.

[0202] In this embodiment, the optical pump is located on the carriage 15. However, the optical pump can be located independent or remote from the carriage.

[0203] This embodiment can also be modified in that a beam guide with a reflector element is provided instead of the light guide, which can then be omitted entirely or can be guided only to the carriage if the optical pump is located remote from the carriage.

[0204] Preferably, an ND:YAG laser is used as the excitation laser and one or more laser diodes with a wavelength of 808 nm are used as the optical pump, however, other lasers such as a Yb:YAG laser can also be used.

[0205] According to a further embodiment, the beam guide from the light source to the pivot arm 16 is formed by a light guide. The light guide is guided from the light source to the pivot arm 16, the light guide being arranged with its end remote from the light source under the pivot arm 16 in the area of ​​the carriage 15. The light guide is connected to the pivot arm 16 in such a way that the light guide is guided along the pivot arm in the area of ​​the carriage 15 and its end remote from the light source point is guided towards the free end of the pivot arm 16. A reflector element designed as a mirror is arranged at the free end of the pivot arm 18. However, the reflector element can also be represented by other optical elements that deflect the light beam, such as a prism.

[0206] The light beam emitted by the light source is transmitted by the light guide and emitted at its end remote from the light source such that the light beam is deflected along the pivot arm 16 towards the reflector element, preferably parallel to the pivot arm 16. A second reflector element is arranged at the free end of the pivot arm 16 and deflects the light beam downwards towards the treatment area. Optionally, an optical lens for focusing the light beam can be provided in the beam path between the end of the light guide and the reflector element. Instead of an optical lens, an objective lens can also be provided so that the focusing of the light beam can be varied and / or the reflector element can be curved accordingly.

[0207] In such an arrangement, multiple processing heads 17 can therefore be provided on carriages 17 movable along the rail unit 14, each by means of a pivot arm 16, ensuring that the individual light guides do not intertwine with one another. This makes it easy to make a 3D printer 1 with at least 8, preferably at least 12, in particular at least 16, processing heads 17, all of which can be exposed to the light beam simultaneously or substantially simultaneously.

[0208] In this exemplary embodiment, the rail units 14, and thus the swivel arms 16 attached to them, are arranged at different levels, so that the swivel arms 16 arranged in the central rail unit 14 cannot collide with the swivel arms 16 arranged in the outer rail units 14. If all rail units are arranged at the same height, the heights of the swivel arms 16 can also be designed to be different. This can be achieved, for example, by mounting the swivel joints at different heights on the individual carriages 15. However, the rail units can also be arranged all in one plane.

[0209] In the exemplary embodiment described above, the pivot arm 16 is not vertically adjustable. However, within the scope of the invention, it is also possible to provide the carriage 15 with a device for adjusting the vertical position of the pivot arm 16 or to make the rail unit 14 adjustable in the vertical position. This can be particularly advantageous when the powder bed 12 is being scraped by the scraper 11 in order to leave enough space for the movement of the scraper between the powder bed 12 and the pivot arm 16, so that after the scraper 11 has again gone outside the area of ​​the powder bed 12, the pivot arm 16 can be lowered in order to position the treatment head 17 as close as possible to the surface of the powder 6 located in the powder bed 12.

[0210] The light sources for the individual processing heads 17 can be designed in the same way, each generating a light beam with the same intensity and the same frequency or the same frequency range. However, within the scope of the invention, it is also possible to provide different light sources for different processing heads, with light being emitted at different frequencies or frequency ranges and / or with different intensities. It is also possible to provide light sources whose wavelength of light can be tuned over a certain range. Such frequency tunable lasers are known and usually have semiconductor amplifiers.

[0211] One advantage of the present invention lies in the fact that different areas of powder 6 in powder bed 12 can be exposed to light, and therefore heat, simultaneously by multiple processing heads 17, and melted or sintered simultaneously. This parallelizes the manufacturing process, significantly speeding it up compared to conventional 3D printers.

[0212] According to a further embodiment, an optical distance sensor is used to measure the distance between the reference element and the distance sensor. Such distance sensors are inexpensive and have a very high resolution. They can determine the distance to the reference element by triangulation. In triangulation, a light beam, for example a laser beam, is focused on the measurement object and observed with a camera, a spatially resolved photodiode or a CCD line arranged next to it in the distance sensor. If the distance of the measurement object from the sensor changes, the angle at which the light spot is observed also changes and therefore the position of its image on the receiver. The distance of the object from the laser projector is calculated from the change in position using an angular function. Distance measurement using triangulation is very simple and inexpensive. If the accuracy requirements are low, radiation from a light-emitting diode can also be used as the light beam.

[0213] Distance can also be measured by measuring the phase position. When measuring the phase position, a light beam, for example a laser beam, is emitted. The phase shift of the reflected laser beam compared to the emitted beam depends on the distance. This phase shift can be measured and used to determine the distance traveled. Distance measurement by measuring the phase shift is very accurate.

[0214] When measuring distance using transit time, a short pulse of light, a constant beam of light or a light modulation is emitted. The pulse transit time is the time it takes for a light beam to travel from the source to the reflector and back again to the source. By measuring this transit time, the distance between the light source and the object can be determined by the speed of light. Sensors that scan lines, surfaces or planes can also be used to measure distance, for example stereo cameras for three-dimensional localization of one or more objects. Such sensors do not need to swivel because their receiving area is large.

[0215] Instead of optical sensors, other sensors may be used, such as ultrasonic sensors or sensors that use the time of flight of radio waves to determine distance.

[0216] Regardless of the type of sensor, the advantage is that the position of the processing head can be set very accurately thanks to a control loop, which can also be used to determine the position of the processing head, which according to the first exemplary embodiment can only move in one plane.

[0217] For precise positioning, the actual position of the moving components, e.g. the processing head 17, can be detected after the start. For this purpose, the distance between the processing head 17 and the respective distance sensor can be measured. The actual position is detected by measuring the distance with the distance sensor. The actual position of the processing head can be easily determined from the three distance measurements. If the actual position corresponds to the target position, no further actions are required and the production of the part can continue.

[0218] The position of a movable component, e.g. the processing head 17, can be determined absolutely in space. However, the position of a movable component can also be determined relative to another component. In the latter case, the distance between the two components is determined.

[0219] The actual position of the movable component can be controlled in each spatial direction or along each axis separately and sequentially until the target position is reached, however, it is also possible to control the position of the movable component in all three spatial directions or along all axes simultaneously.

[0220] The distance sensor can be arranged at a fixed position in the processing chamber 2 of the 3D printer 1. The distance sensor can determine the position of the surface of the powder bed 12 via distance measurements and then determine the position of the movable component, for example the processing head 17, with the help of further distance measurements. The processing head 17 can be moved to a target position depending on the position of the powder bed 12, i.e. the height of the powder bed 12, in order to set the required distance between the processing head 17 and the surface of the powder bed 12. The movement of one or more processing heads 17 to their target positions can thereby be performed with the help of the above-mentioned control and adjustment device. It is also possible to connect or arrange one or more distance sensors to the processing head 17 to directly determine the distance between the processing head 17 and the powder bed surface in order to subsequently move the processing head 17 from the surface of the powder bed 12 to the target distance.

[0221] If the actual position does not correspond to the target position, the position of the processing head 17 is corrected. For this, the drive can be started and the traverse speed of the processing head 17 can be set depending on the distance between the actual position and the target position. The smaller the distance between the actual position and the target position, the lower the traverse speed can be selected. After a set unit of time and / or a defined distance has been traveled, the actual position can be recorded again and then corrected if necessary. It is also possible to record the actual position continuously. In this way, a closed control loop can be created. This control makes it possible to move the processing head 17 exactly to the target position using a simple, cheap and in itself not very precise moving device. The accuracy of the positioning is determined exclusively by the distance measurement with the distance sensor. [Explanation of symbols]

[0222] 1 3D printer 2 Processing chamber 3 Production unit 4 Storage unit (Vorratseinrichtung) 5 Supply container 6 powder 7 Bottom wall 8 Supply piston cylinder unit 9. Building Platform 10 Production piston cylinder unit 11 Scraper 12 Powder bed 13 Modules 14 Rail unit (Schieneneinrichtung) 15 Carriage (Schlitten) 16 Processing Heads 17 Swivel Arm 18 Module holder 19 Halterung 20 Longitudinal 21 Bonding unit 22 Control unit 23 Horizontal 24 Production control unit 25 Planning and Control Unit (Planungssteuereinrichtung)

Claims

1. 1. An apparatus for additive manufacturing of a part, preferably by selective melting or sintering, comprising: at least one module having a processing head for directing a light beam to a processing area, a pivoting arm on which the processing head is disposed, and a carriage to which the pivoting arm is rotatably mounted, the at least one module being movable along a rail unit; a control unit in which module parameters defining predetermined properties of the modules can be stored or are stored, the control unit being configured and designed to control different modules based on the module parameters, so that modules can be exchanged in the additive manufacturing apparatus for parts, which can be controlled by the control unit, preferably without further configuration steps; 1. An additive manufacturing device comprising:

2. A module comprises at least one processing head, at least one pivot arm and at least one carriage, or said module comprises several processing heads with corresponding pivot arms, carriages and rails. The additive manufacturing device of claim 1 .

3. the modules have identifiers that include module parameters or automatic assignments to said module parameters, and in particular different module parameters can be stored in the additive manufacturing device for different modules; The additive manufacturing device of claim 2 .

4. A planning control unit for automatically generating a production process plan for manufacturing a specific part, in particular by an additive manufacturing apparatus for a part according to any one of claims 1 to 3, comprising: the planning control unit is configured and designed to generate at least one production process plan based on CAD data of the part to be manufactured; the planning control unit is configured and designed so that an optimized configuration is determined based on the CAD data of the part to be manufactured, and a production process plan is created based on the optimized configuration; In particular, a plurality of production process plans are generated for different configurations of the additive manufacturing machine, the different configurations being defined by different module parameters, such that one of the plurality of production process plans can be selected with respect to production time and / or product quality parameters; A planning control unit.

5. The planning control unit is configured and designed to automatically select a production process plan according to predetermined parameters.

5. The planning control unit according to claim 4, characterized in that:

6. The module parameters are: different numbers, and / or different types of pivoting arms, especially in terms of length and / or pivoting range, and different types and positioning of rail units within the processing chamber, in particular in the X or Y direction parallel to the build platform, and preferably in the Z direction, and therefore in height perpendicular to said build platform; and / or Different types of carriages, especially in terms of structural design, and / or different types of treatment heads, especially in terms of intensity or temperature, and / or Different number of processing heads per rail unit Contains The additive manufacturing device according to any one of claims 1 to 3, characterized in that

7. different control parameters, including different movement speeds or accelerations of the carriage and swivel arm and / or different printing speeds and / or different intensities or temperatures of the processing head, are stored in a production control unit and / or a planning control unit, which can be automatically and / or manually selected based on the part used, in particular the module of the additive manufacturing device, and / or based on the build plan for the part; The additive manufacturing device according to any one of claims 1 to 3, characterized in that

8. Modules with a larger number of carriages per rail unit have processing heads with shorter pivot arms, and modules with a smaller number of carriages per rail unit have longer pivot arms. The additive manufacturing device according to any one of claims 1 to 3, characterized in that

9. Two or more rail units are designed to be movable. The additive manufacturing device according to any one of claims 1 to 3, characterized in that

10. The control unit is a production control unit, which also comprises a planning control unit, thus forming the control unit. The additive manufacturing device according to any one of claims 1 to 3, characterized in that

11. providing at least one distance sensor, preferably electro-optical distance measuring, for optically monitoring the position of said processing head; The additive manufacturing device according to any one of claims 1 to 3, characterized in that

12. 10. A method for calculating an optimal configuration of an additive manufacturing device for a part, in particular for use with an additive manufacturing device according to any one of claims 1 to 3, comprising: Retrieving CAD data for the part to be manufactured (from the part data); determining local work requirements for each layer; determining an optimal configuration of modules according to the processing requirements of all layers; A method comprising:

13. The optimal configuration is: Allocating multiple processing heads to a print area with a large accumulation of material, and / or Placing a short pivot arm in a print area with a large buildup of material; and / or Allocating a small number of processing heads to a print area having a small surface area, and / or Allocating a long pivot arm to a printing area with a small surface area 13. The method of claim 12, wherein the method is achieved by:

14. 1. A method for additively manufacturing a part, preferably by selective melting or sintering, by a method for calculating an optimal configuration of an additive manufacturing device for a part, in particular using an additive manufacturing device according to any one of claims 1 to 3, comprising: storing module parameters defining predetermined characteristics of the module within the control unit; - after changing the configuration of the additive manufacturing apparatus, controlling different modules according to a production process plan by the control unit based on module parameters without further setup procedures; A method comprising:

15. A method for generating a production process plan for manufacturing a specific part, in particular by a planning control unit of an additive manufacturing apparatus according to any one of claims 1 to 3, comprising: Retrieving CAD data for the part to be manufactured; generating at least one production process plan using said planning control unit based on said CAD data of said part to be manufactured; generating different configurations of the modules of the additive manufacturing apparatus for a part; and based thereon, creating a plurality of production process plans, the production process plans defined by different module parameters of the additive manufacturing device for a part; selecting a production process plan based on production time and / or product quality and / or quantity, wherein the production process plan and the appropriate configuration are output; A method comprising:

16. Different configurations result in different components, in particular different modules, different application speeds per area, which in turn result in different arrangements or positions of the treatment heads and the treatment areas assigned to them, and / or different numbers of treatment heads in different areas. The method of claim 15, wherein:

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