DE102018127311A1 - Thermoelectric removal of support structures - Google Patents

Abstract

The invention relates to a method for detaching an additive manufacturing product (2) from a support structure (50, 50 ') and / or detaching the support structure (50, 50') from a construction platform (12) using an electrical current in at least one predetermined melting range (51, 51 ') of the support structure (50, 50'), so that the electric current leads to a melting of the support structure (50, 50 ') in at least a section of the predetermined melting area (51, 51'). Optionally, the method can comprise at least one separation step.

Description

The invention relates to a method and a device for detaching an additive manufacturing product from a support structure and / or for detaching the support structure from a construction platform. The invention further relates to a method and a system for providing an additive manufacturing product, the additive manufacturing product being built up from a building material in an additive manufacturing process with a support structure connected to the additive manufacturing product.

Additive manufacturing describes a process in which additive manufacturing products or components are manufactured directly or indirectly on the basis of digital 3D design data, for example (and in particular) from shapeless construction materials. The term “3D printing” is therefore often used as a synonym for additive manufacturing. Such components are usually produced, although not necessarily in layers, using both solid, but also pasty or liquid materials with different physical and chemical properties.

Additive manufacturing processes are becoming increasingly relevant in the production of prototypes and now also in series production. This applies in particular to the manufacture of such manufacturing products that are characterized by a high degree of geometric complexity. The production of models, samples and prototypes with additive manufacturing processes is often referred to as "rapid prototyping" and the production of tools and other end products as "rapid tooling" or "additive manufacturing".

A key feature of additive manufacturing is selective, i.e. H. spatially limited, in particular layer-by-layer, solidification of at least one building material. The mostly powdery building material is first introduced in the form of a thin layer into a process space or a process chamber of a device (manufacturing device) for additive manufacturing, for example onto a building platform of the device. In many processes, the structural material is selectively solidified by means of electromagnetic radiation, in particular light and / or thermal radiation. Alternatively, the build-up material can also be irradiated with particle radiation, such as electron radiation, for solidification.

• Die Bestrahlung der Schicht des Aufbaumaterials erfolgt auf Basis von vorgebbaren 3D-Konstruktionsdaten eines herzustellenden Bauteils so, dass nur solche Bereiche der Schicht, die Bestandteil des herzustellenden Bauteils werden sollen, bestrahlt werden. Durch die lokal eingebrachte Strahlungsenergie werden die Pulverpartikel des Aufbaumaterials teilweise oder vollständig aufgeschmolzen bzw. teilweise oder vollständig versintert und kühlen anschließend soweit ab, dass sie sich miteinander zu einem Festkörper verbinden. Der Bereich der Schicht, in dem sich die aktuelle Verfestigung des Aufbaumaterials vollzieht, wird auch als „Verfestigungsbereich“ bezeichnet.

Two commercially important processes in which the building material is solidified by irradiation with radiation energy are “selective laser sintering” (SLS) and “selective laser melting” (SLM):

• The layer of the build material is irradiated on the basis of predeterminable 3D construction data of a component to be manufactured in such a way that only those areas of the layer that are to become part of the component to be manufactured are irradiated. Due to the locally introduced radiation energy, the powder particles of the building material are partially or completely melted or partially or completely sintered and then cool down to such an extent that they combine to form a solid. The area of the layer in which the current consolidation of the building material takes place is also referred to as the "consolidation area".

The solid resulting from the selective irradiation of the layer of the building material corresponds to a layer of the component to be manufactured or a "component layer". The component layer is generally understood in the context of the present invention to mean a three-dimensional body which is defined by a “cross-sectional area of the component layer” and a corresponding depth or thickness of the component layer. In the following, the “cross-sectional area of the component layer” or “component cross-sectional area” is to be understood in the case of a plan view of the layer of the building material, the area of the layer which is solidified in this layer in order to produce the component. For further delimitation, it should be pointed out here that in the context of the invention, a “layer” is understood to mean the building material applied in the form of a layer in a coating and subsequent consolidation process in the process space or in a construction field of the production device.

In a layer of the building material, several separate, i.e. H. “Layer areas” to be consolidated that are not connected to one another can be arranged, wherein the layer regions to be consolidated can belong to a single component or to several separate components. In the former case, the entirety of the layer regions to be consolidated would correspond to the component layer of a component to be consolidated.

For the sake of clarity, it is assumed below that only a single component layer of a single component to be produced is arranged in each layer, the invention being not restricted to this.

To produce a complete component, thin layers of the build material are repeatedly introduced into the process space and selectively solidified, the individual consolidated component layers combining to form a common component.

In addition to various plastics and composite materials, metallic construction materials are preferably used as construction materials. Due to the high melting or sintering temperatures, a high degree of locally introduced radiation energy is required, particularly in the case of metallic building materials, for the selective solidification of the layer. As a result, especially the currently irradiated, ie the top layer in the process chamber, in particular in the consolidation area, is strongly heated, which can lead to high thermal stress or stress in the solidified but also in the currently solidifying building material. In principle, the occurrence of thermal loads during additive manufacturing can adversely affect the quality of the finished component.

In order to reduce the occurrence of thermal loads in a region of the component to be manufactured during additive manufacturing, a number of support structures, sometimes also referred to as support structures, are usually arranged in the process space of the production device, the support structures usually being produced together with the component in the additive manufacturing process will. Furthermore, the heat structures in the component to be produced can also be influenced by means of the support structures, in that part of the process heat is derived from the additive manufacturing into an area outside the component to be produced. The quality of the finished component can advantageously be increased in this way.

The support structures can be arranged in such a way that they connect different sub-areas or compartments of the component to be manufactured with one another, ie. H. the support structures are arranged in an area within the component.

In general and within the scope of the invention, however, a number of support structures are arranged in a region between the component to be manufactured and the construction platform of the production device such that the finished component, i. H. as soon as all component layers of the component have solidified, lie on the support structures or are "supported" by them. The component to be produced can therefore be built up on the support structures during additive production, the support structures and the component typically being produced together in the additive production process.

The arrangement of the support structures in the process space of the production device can take place according to a predeterminable pattern or can be specifically adapted to the respective configuration of the component to be manufactured. In general, the support structures are firmly connected to the construction platform of the production device in a lower or basal region and firmly to a region of the component to be produced in an opposite upper or apical region. The connection between the support structures and the building platform or the component is preferably made by means of material bonding. As an alternative to the construction platform, the support structures can also be constructed on a base plate of the production device, which then serves as a construction base.

Notwithstanding the advantages explained above, the removal or severing of the support structures, which is usually done mechanically, has turned out to be a complex process after the completion of the manufacturing process.

To facilitate the separation process, the describes DE 10 2015 207 306 a method for producing support structures with a weakened area, the weakened area being easier to cut through than the remaining area of the support structures. However, the support structures still have to be cut mechanically and essentially one after the other. With a large number of support structures, the separation process can therefore be a time-consuming and labor-intensive process, in particular if the support structures are not arranged parallel to one another due to the component geometry, or if the weakened regions are not arranged at the same height of the support structures.

In the WO 2017/029276 A1 a method is therefore described in which the support structures are severed by means of a chemical process. However, the chemicals used here also potentially attack the surface of the component or remove material from the finished component.

It is therefore an object of the present invention to provide an improved or alternative method for detaching (detachment method) and a corresponding method for providing (provisioning method) an additive manufacturing product on the one hand, and a device for detaching (detaching device) and a system for providing (providing system) one to provide additive manufacturing product, on the other hand, which avoid the disadvantages mentioned above and which preferably enable a more efficient and accelerated detachment of an additive manufacturing product from a support structure and / or the support structure from a construction platform.

This object is achieved by a detachment method according to claim 1 and a preparation method according to claim 10, and by a detachment device according to claim 12 and a delivery system according to claim 13 solved.

A method according to the invention relates to the detachment of an additive manufacturing product from a support structure and / or the detachment of the support structure from a construction platform of a device for additive manufacturing of a number of manufacturing products, which is why the method is also referred to below as the “detachment method”. The method according to the invention can preferably be used after the additive manufacturing, i. H. as soon as an additive component has been fully manufactured or an additive manufacturing process has ended.

As explained at the beginning, the support structure is preferably produced in an additive manufacturing process together with the additive manufacturing product in a process chamber of a device for additive manufacturing and is connected to it, preferably permanently connected. This preferably means that the additive manufacturing product and the support structure are built up in layers and essentially at the same time or in parallel, for example starting from a construction platform of the manufacturing device.

In addition to those areas of the layer which are to become part of at least one component to be produced, areas of the layer which should be part of one or more support structures to be produced are preferably solidified in a layer of the build material, the consolidation preferably by selective irradiation of the build material and / or another product substance is carried out by means of at least one high-energy beam, for example a laser beam.

For the additive manufacturing process, a large number of conductive construction materials in powder form can be used to select the one or those which are to be used, in particular from the field of metal-based construction materials. Alternatively, self-conducting, i.e. H. intrinsically conductive plastics such as polypyrrole or polythiophene can be used. Furthermore, electrically non-conductive plastics are also suitable as construction materials if they are replaced by electrically conductive substances, e.g. B. in the form of soot or metal, to maintain electrical conductivity. Such enrichment with electrically conductive substances can be achieved both by admixing (blending, admixing, and much more) as well as by producing a composite building material, in the powder grains of which the electrically conductive material is integrated. In this case, not every powder grain has to comprise the electrically conductive material; in the end, it is sufficient if there is sufficient electrically conductive material in the build material that the support structure produced with it is electrically conductive.

In general, as in the context of the invention, a support structure, as explained at the outset, is to be understood as a support structure or a supporting element made of solidified construction material, which is arranged in a region between a construction platform or base plate of the production device and a region of the finished component is not part of the resulting finished component itself. In other words, the finished component, in particular after removal of unconsolidated building material from the process space, lies at least in regions on the support structure or is at least partially supported and / or laterally supported by it. Therefore, for the sake of simplicity, it is assumed below, unless explicitly stated otherwise, that a building platform located at the bottom is connected at least in one area to a component located above or above by a centrally arranged support structure, so that the component forms the upper end of this arrangement . However, the invention should not be limited to such an arrangement of the support structure.

Different types of support structures are usually used in additive manufacturing. A support structure referred to below as a “one-piece” support structure can, for example, comprise a solid, uniform substructure or a base area, which is firmly connected on an underside, in particular by means of a material connection, to the construction platform or to the base plate of the production device, provided the latter is used as a construction base serves. On a top, i.e. H. On the side of the base region opposite the construction platform or base plate, a number of separate support struts can be arranged, which are connected directly, preferably cohesively, to an area of the component to be produced in an apical region of the support structure. A support structure can accordingly be connected to the construction platform by means of only one connection surface or a contact point, a plurality of separate connection surfaces being present with respect to the component, as will be explained in detail later. Under certain circumstances, this connection can only be realized when the component is completely manufactured, i. H. when all component layers are solidified. A finished component is assumed below, the additive manufacturing process having already been completed.

As an alternative or in addition, support structures designed in a “stand-alone” manner can also be arranged in the process space, each support structure comprising its own separate base area. Regardless of the precise design of the support structure, a fixed, direct and continuous connection between the building platform or the base plate and the finished component can be realized.

According to the invention, the component is detached from the support structure and / or the support structure is detached from the construction platform or the base plate using an electrical current in at least one predetermined melting area of the support structure, the electrical current at least melting the support structure in at least a section of the support structure Desired melting range leads, which is also referred to in the following as "local melting" of the support structure. Melting of the support structure is to be understood here to mean at least melting, but preferably melting or melting, of the support structure in the target melting area.

In order to melt the support structure or to melt it completely in at least a section of the target melting area, an electric current with a suitable strength can be introduced into an area of the building platform or base plate and / or of the component and / or the support structure or through such an area be conducted so that the solid material of the target melting area is heated to such an extent as a result of the electric current in the target melting area that it is at least partially liquefied (melted) and / or evaporated. This means that a phase change from the solid to the liquid or gaseous state takes place in the solidified building material of the target melting area, the amount, in particular the amount of substance, of the original solid material of the target melting area also being able to be reduced.

If the support structure is completely melted through in at least a section of the target melting area, a gap or a gap arises within the support structure as a result of this severing. In contrast, other areas of the support structure, in particular areas outside the predetermined melting area, are not melted or severed. As a result of the local melting in a section of the target melting area, the building platform or base plate and the component are no longer connected to one another in one piece. This means that the complete detachment of the component from the support structure and / or the support structure from the construction platform can only be achieved by means of an electric current in a predetermined melting area of the support structure.

The detachment method according to the invention can optionally also comprise one or more separation steps in order to detach the additive manufacturing product from the support structure and / or the support structure from the construction platform. This means that the detachment process according to the invention can include, in addition to an already explained “melting step” in parallel or downstream, at least one “separation step”. The detachment method according to the invention can then preferably comprise at least two steps, wherein in a first step at least a portion of the target melting area of the support structure is melted using an electric current (melting step). In this embodiment of the detachment process, the target melting area can only be “melted on locally”, ie not completely cut through. This means that there is still a direct connection between the construction platform and the component. The material in the target melting area can preferably be weakened to such an extent as a result of the electrical current, in particular as a result of heating in the target melting area, that the component can be separated from the building platform or base plate by a low mechanical load, the mechanical effort required for this is less than without a previous material weakening in the target melting range.

A second step of the detachment process according to the invention is the (detachment) separation of the support structure from the additive manufacturing product and / or the construction platform in the target melting range in accordance with a suitably selected separation process (detachment step). Depending on the specific design of the detachment process, the separation step can be (temporally) downstream of the melting step, i. H. the separation step and the melting step can be separate substeps of the stripping process.

However, it may also be the case that the melting step and the separating step coincide in time. This means that the two sub-steps can also be understood as sub-aspects of a single step, namely if a force is applied during the "local melting" using the electric current (according to step 1) that causes the separation of the support structure (according to step 2) causes. In general, the force for the separation described above does not necessarily have to be carried out by an independent device, for example a separation unit, but instead it can, for. B. gravity can also be used to effect the separation.

At this point, it should be pointed out that the detachment method according to the invention is not limited to a single support structure, but advantageously also for detaching an additive manufacturing product from a plurality of support structures and / or for detaching a plurality of support structures or components from a construction platform Manufacturing device is suitable, as will be explained later.

Depending on the specific embodiment of the method, the detachment method according to the invention can advantageously make it possible for the entirety of support structures, which is arranged between the component and the construction platform in the process space to produce an additive manufacturing product, to be completely and only by applying an electrical current once can be separated essentially at the same time. A time-consuming mechanical processing or severing of individual support structures can thus advantageously be dispensed with. Furthermore, the method according to the invention can also make the use of chemicals which are hazardous to health unnecessary in the context of additive manufacturing. The method according to the invention thus enables considerable time and resources to be saved in additive manufacturing and therefore provides an efficient solution for detaching an additive manufacturing product from the support structure and / or the support structure from a construction platform after an additive manufacturing process.

A device according to the invention for detaching an additive manufacturing product from a support structure and / or for detaching the support structure from a construction platform comprises at least one current application device with a coupling device for introducing an electrical current into at least one area of the support structure, preferably into a predetermined melting area of the support structure, so that the electric current leads to melting of the support structure in at least a portion of the predetermined melting area of the support structure. This means that the detachment device, in particular the current application device, is preferably designed and, in particular, powerful enough to provide or generate a sufficiently strong electrical current in the target melting area in order to melt at least one support structure in the target melting area, particularly preferably to melt completely. The detachment device can preferably be designed to melt a plurality of support structures, that is to say a plurality of predetermined melting areas, essentially in parallel or simultaneously, ie. H. to melt or melt depending on the chosen procedure, although this can also be different for different support structures.

Optionally, the detachment device can comprise at least one separating unit, which is designed to separate the support structure from the additive manufacturing product and / or the construction platform in the target melting area, in particular if the target melting area was previously “locally melted”. The optional separation unit is used to carry out the above-described separation step of the method according to the invention, that is to say to separate the support structure from the additive manufacturing product and / or the construction platform in the target melting range. Since the melting and the separating step coincide in time or these two steps can also be understood as partial aspects of a single step (see above), the separating unit can be implemented by means of a special design of a current application device: namely, the at least one target melting range is achieved by means of an electrical current completely melted, the connection between the additive manufacturing product and the support structure or the support structure and the construction platform is already completely separated. The separating unit can therefore support z. B. still include a mechanism that moves the manufacturing product and / or the construction platform, for example lifts it away, tilts or the like. B. gravity can be used to advantage to transfer the detached element (construction platform or manufacturing product) to a desired location and to maintain the separation effect from the detachment process permanently.

To melt the support structure, the electrical current can be introduced directly into an area of the component and the building platform by means of the detachment device, for example via a number of defined contact points of the component or the building platform, as will be explained in detail later. Alternatively or additionally, the electrical current can also be introduced directly into a region of the support structure via suitable contact points.

For this purpose, the coupling device of the detachment device, in particular the current application device, can comprise a number of modularly positionable contact elements, the contact elements for direct, contact-bound (galvanic) introduction of the electrical current into a region of the component, the construction platform and / or the support structure on the aforementioned Contact points are suitable.

Alternatively or additionally, the coupling device of the detachment device according to the invention can comprise at least one induction coil or the like for generating an alternating magnetic field in the support structure, eddy currents being generated at least in a region of the support structure, i. H. The electrical current can be introduced without contact or inductively. In addition, the detachment device according to the invention can comprise a large number of further components, as will be explained later.

In a method according to the invention for providing an additive manufacturing product, the additive manufacturing product is made from one in an additive manufacturing process with at least one (preferably fixed) support structure connected to the additive manufacturing product Construction material built up. The provision can include additive manufacturing (manufacture) of the component in a manufacturing device and / or delivery of the (finished) component to a detachment device. As already mentioned, the support structure can preferably be firmly connected to a construction platform or base plate of a device for additive manufacturing on a side of the support structure that is opposite the component. The method is equally suitable for producing a plurality of production products or components in only one additive production process, it being possible for each component to be connected to a number of support structures.

The provision method according to the invention, in particular the production of the component, preferably takes place in such a way that the detachment of the additive manufacturing product from the support structure and / or the detachment of the support structure from the construction platform can take place in the predetermined melting area of the support structure, in particular according to the detachment process explained above. Alternatively, the support structure can be designed such that, as mentioned, it can be locally melted or locally weakened by means of the detachment process.

• - eine Fertigungseinheit zum Aufbau eines additiven Fertigungsprodukts in einem additiven Fertigungsprozess mit einer an das additive Fertigungsprodukt angebundenen Stützstruktur aus einem Aufbaumaterial, und
• - eine erfindungsgemäße wie oben ausgeführte Vorrichtung zum Ablösen, insbesondere zum Ablösen des additiven Fertigungsprodukts von der Stützstruktur und/oder zum Ablösen der Stützstruktur von einer Bauplattform in einem Sollschmelzbereich gemäß dem erfindungsgemäßen Ablöseverfahren.

The invention is further implemented using a system for providing an additive manufacturing product, comprising

• a manufacturing unit for building an additive manufacturing product in an additive manufacturing process with a support structure made of a building material and connected to the additive manufacturing product, and
• a device according to the invention as described above for detaching, in particular for detaching the additive manufacturing product from the support structure and / or for detaching the support structure from a construction platform in a predetermined melting range according to the detachment method according to the invention.

The provision system according to the invention can be designed as a unit in which the manufacturing unit and the detaching device are integrated, for example as two stations of a machine or even as a single station in which both the additive manufacturing of the manufactured product and the detaching are carried out. Alternatively, the manufacturing unit and the detachment device are two separate or separable units, for example, each with its own housing. In the latter case, a transport unit could be provided in order to transport the production product as well as at least one support structure connected to it and possibly a construction platform from the production unit to the detachment device. A certain (advantageous) atmosphere surrounding the component or the other components could preferably be provided by the transport unit during the transport.

A production unit (or synonym: device) which can be used in the context of the invention for the additive production of a number of production products in a production process comprises a feed device for introducing a build material in layers into a process space, preferably a coating device for applying the build material in layers on a construction field and a consolidation device for the selective solidification of the building material at predeterminable points as well as a control device, to name just a few components.

The control device can preferably comprise a support structure data calculation module in order to control the device, in particular the solidification device of the device, in accordance with an irradiation strategy in such a way that the additive manufacturing product and at least one firmly connected support structure can be built up from the build material, the support structure by the device is formed in such a way that the support structure has at least one target melting area, the target melting area preferably having a higher electrical resistance, particularly preferably a smaller material cross section, than a base area of the support structure and / or a component and / or a construction platform. The material cross section of the target melting area is to be understood in particular as the sum of the line cross sections of the melting bodies of the target melting area, as will be explained later.

Further, particularly advantageous refinements and developments of the invention result from the dependent claims and the following description, the independent claims of one claim category also being able to be developed analogously to the dependent claims and exemplary embodiments of another claim category, and in particular also individual features of different exemplary embodiments or variants can be combined to new embodiments or variants.

It should first be pointed out that by means of the detachment method according to the invention, a plurality of support structures can be detached from at least one component or one construction platform simultaneously, ie essentially simultaneously. Likewise, the detachment method according to the invention can also be used to detach a plurality of additive components from one or more support structures in each case. In the following description of the invention, for the sake of clarity, of a single one Support structure, the support structure being connected to a single component, wherein, unless explicitly stated otherwise, the features of an individual support structure or a single component described below are also intended to apply equally to a plurality of support structures or components.

An electrical current can preferably be supplied to the additive manufacturing product and / or the support structure and / or the construction platform from the outside via at least one contact point. In other words: the electrical current is supplied to the support structure via at least one contact point on the additive manufacturing product and / or the support structure and / or the construction platform. The manufacturing product, the support structure and the construction platform are thus particularly preferably implemented as components of an electrical circuit.

The contact point can preferably be with the help of an exposed “contact flag” and / or a “socket” or “coupling”, ie. H. an inward-facing contact opening. In order to introduce an electrical current into the circuit mentioned above, the respective contact point can be connected directly, in particular by cable, to a (possibly) external power source of the separation device, in particular the current application device, by means of a number of contact elements which can be positioned modularly. Such contact elements can e.g. B. with the help of "crocodile clips" or "banana plugs", in particular so that a galvanic connection between the respective contact point and the contact element can be made. The contact elements can be seen as part of a coupling device of the current application device or form a coupling device.

A voltage is therefore preferably applied in a contact-bound manner by means of the current application device of the detachment device in at least one area of the building platform or the base plate and the component such that a current flows between the component, the centrally arranged support structure and the building platform.

Advantageously, the application of an electric current in a circuit designed in this way can result in the entirety of all of the predetermined melting areas of the support structures which were arranged between the component and the construction platform for the production of the component being melted completely and essentially simultaneously. This method step, namely the application of an electric current, advantageously has to be carried out only once for each component, so that the removal of the finished component from the detachment device or the preparation system can be accelerated after the preparation process has ended.

Depending on the configuration of the support structure, it is possible that the target melting area consists of a single element to be melted or only one melting body to be melted.

In a preferred embodiment, however, a predetermined melting area comprises a plurality of separate elements or melting bodies to be melted, preferably arranged parallel to one another. In the example of a one-piece support structure explained at the outset, the predetermined melting area could therefore be realized by a plurality of separate support struts. In other words, a target melting range is understood to mean both a single melting body to be melted through and a plurality of individual melting bodies. In the following, a target melting range with a plurality of melting bodies is assumed as an example.

At this point, it should be pointed out that a support structure can in principle also comprise more than just a predetermined melting range. Unless explicitly stated otherwise, the invention is described below as a preferred example with reference to a support structure with only one target melting range.

In one embodiment of the detachment process, the target melting area of the support structure can be melted completely, in particular in accordance with its entire length or width, so that the target melting area or the individual melting bodies largely dissolve or evaporate as a result of the electrical current, the length of the Desired melting area can also essentially correspond to the length of the entire support structure along its main direction of extension.

However, it is also conceivable that the target melting area is melted over its entire width, but not over its entire length. This means that all melting bodies of the target melting range are completely severed, i. H. a gap is created, but at least a partial area of the target melting area on the component or on the construction platform is retained.

The design of the target melting range is essentially determined by the number and design of the individual melting bodies. The length or longitudinal extent of the target melting area corresponds to the extent of the same along a main direction of extension of the respective support structure, the main direction of extension of the support structure being defined such that it runs the shortest route between the building platform or base plate and the component. The length of the target melting range is therefore defined by the smallest length of a melting body within the target melting range.

A width or a diameter of the individual melting bodies essentially corresponds to an extension perpendicular to the longitudinal extension of the respective melting body. The area of a melting body, which results from a cut transverse to the longitudinal extent of the melting body, is referred to below as the "cross-sectional area of the melting body". Accordingly, the sum of the individual cross-sectional areas of the melting bodies of a target melting area describes the “cross-sectional area of the target melting area”.

As explained above, at least one contact point of the component or of the construction platform or of the support structure itself can be connected to a number of contact elements of the detachment device according to the invention for the contact-bound introduction of the electric current into the support structure. If more than one component was produced in an additive manufacturing process, a further electrical circuit can be formed between the construction platform and the further component to detach at least one further component from the construction platform, again a number of support structures in an area between the construction platform and the further component can be arranged. In order to apply the electrical current, the contact element which has become free can be repositioned by the previously detached component at a contact point of the further component to be detached.

However, an electrical current can preferably also be supplied to the further component by means of a separate or “component-specific” contact element. The individual contact elements, ie. H. the respective component-specific contact elements are controlled separately by the detachment device, d. H. can be individually supplied with electrical current.

Particularly preferably, after the additive manufacturing process has ended, a single contact element can be positioned in a region of the construction platform, and a component-specific contact element can be positioned at the respective contact points of a number of components. Through the separate control of the individual contact elements, in particular the component-specific contact elements, by means of the detachment device according to the invention, an electrical circuit can then be set up between the construction platform and a specific, ie. H. component currently to be detached from the construction platform. Advantageously, the contact elements in question only have to be positioned once, the detachment of a number of components then being able to take place predominantly automatically, preferably sequentially.

Alternatively, the electrical current can also be supplied directly at a contact point of the support structure by means of the contact elements, so that the electrical circuit would only encompass a region of the support structure and the component. The contact point can preferably be arranged in the base region of the support structure.

Such a positioning of the contact elements or an electrical circuit designed in this way turns out to be particularly advantageous if the support structure has already been separated from the building platform or the base plate before the electrical current is applied, or is not connected to a building platform. So it can It may be necessary or advantageous that a component that is connected to the building platform with a massive extrusion is first mechanically detached from the building platform or base plate. In this context, it is possible that the support structures of the component are also mechanically separated from the construction platform. The detachment method is then advantageously suitable for also separating the remaining remains of the support structure from the finished component.

If a component comprises a plurality of support structures, wherein the support structures are not or no longer connected to a construction platform, a contact element can be arranged at a contact point of each support structure. The contact elements can preferably be controlled individually by the detachment device according to the invention.

This advantageously enables automated, preferably sequential, separation of all the support structures of a component, in particular if the support structures are not connected to a common construction platform.

The introduction of an electric current into a region of a support structure can alternatively or in addition to the direct, i.e. H. contact-based methods also take place by means of a contactless method, as will be explained below.

In an inductive method, an electrical current is preferably used in at least a partial area of a support structure by applying a limited magnetic one Alternating field induced. This means that no direct, galvanic contact between the support structure and an external power source is required to form the electrical current in a region of the support structure.

The alternating magnetic field is preferably built up by means of at least one induction coil through which alternating current flows.

The induction coil can preferably also be designed such that it encompasses a process space of the detaching device from the outside. In other words, an inner diameter of the induction coil can be larger than an outer dimension of the process space or the process chamber, in particular larger than the dimension of a construction field of a manufacturing unit of a provision system according to the invention. As mentioned at the beginning, the induction coil is an embodiment of the coupling device of the detaching device according to the invention.

The strength of the magnetic alternating field generated by the coil can be regulated by the current control unit of the detachment device according to the invention, in particular by a computer program product.

The strength of the alternating magnetic field generated by the coil can be determined in such a way that, as a result of the electrical current or eddy currents induced in the support structure, at least one support structure is completely melted locally, the additive manufacturing product of the support structure and / or Support structure can be detached from the construction platform. Alternatively, the support structure can also be locally melted or weakened by means of the alternating magnetic field, so that little mechanical work is required to detach the component from the support structure or the support structure from the construction platform.

The magnetic alternating field of the coil can preferably be limited in a suitable manner so that the eddy currents are induced essentially exclusively in a region of the support structure, with at least in the finished component, that is to say a production product (these terms are also used synonymously below, as in the preceding) no significant electrical current is induced. A significant electric current is in particular one that leads to heating of the finished component, which damages the component, for example due to melting or melting, modification of its structural structure or through the generation of heat stresses. A corresponding limitation of the alternating magnetic field can be implemented, for example, by a suitable arrangement or alignment of shielding devices for magnetic fields and / or the coil itself. The component can therefore preferably lie predominantly outside the heat-affected zone of the eddy current losses.

The coil can particularly preferably be vertically adjustable along the longitudinal extent of the support structure, in particular with respect to the process space.

In order to ensure that the local melting or melting only takes place in a target melting area of the support structure, in particular the target melting area of the support structure can be modeled or designed and arranged and aligned with respect to the coil such that a local maximization of the induced eddy currents can take place, so that, as a result of the resulting local heat development, local melting or melting of the support structure can take place in the respective target melting range. The support structures can be modeled using a support structure data calculation module, as will be explained at a later point in time.

Advantageously, the contactless method enables a number of components to be replaced predominantly simultaneously or simultaneously by means of an electrical current, with no direct contact between the component or building platform or support structure and current source being required for this. This is advantageous in that the separation of the component can also take place without pretreatment of the component in a process chamber, including the process chamber of an additive manufacturing device, that is, a manufacturing unit for building the additive manufacturing product within the scope of the invention. B. can be dispensed with the positioning of a number of contact elements. The time required for the separation process of one or more components from the construction platform can thus be further accelerated.

Regardless of whether the electrical current is introduced galvanically or inductively into the support structure, the general formula applies with regard to the relationship between the electrical voltage U, the electrical resistance R and the current intensity I: U = RI Um the current I at an applied voltage U. To keep as high as possible in the target melting area in order to achieve the targeted melting of the support structure in the target melting area of the supporting structure, the target melting area can therefore have a higher electrical resistance than the base area of the supporting structure adjacent to the target melting area. For this purpose, the material cross section of the target melting area of the support structure can particularly preferably be smaller than the material cross section of the base area of the support structure. The material cross-section, which is also synonymously referred to as the "pipe cross-section", corresponds to the cross-sectional area of the target melting area.

In the context of the invention, the line cross section of the target melting area is understood to mean a smallest line cross section of the target melting area, i. H. the smallest line cross-section that the target melting area comprises along its longitudinal extent. As will be explained later, the line cross section of the target melting area can be different along its longitudinal extent. This also applies analogously to the line cross section of the base region of the support structure.

If a target melting area comprises a number of individual melting bodies, the line cross section of the target melting area corresponds to the sum of the (smallest) line cross sections of all melting bodies of the target melting area. If a support structure comprises several separate partial base areas, the line cross section of the base area of the support structure corresponds to the sum of the (smallest) line cross sections of the separate partial base areas.

Regarding the electrical (total) resistance of the target melting range or the base range with several (current) paths running in parallel, the following generally applies: 1 / R _Ges = 1 / R ₁ + 1 / R ₂ + ... 1 / R _i (whereby "I" corresponds to a number of "connected" melting bodies or partial basic areas), ie the master values are added in the usual way.

By means of a suitable configuration of the target melting area, in particular with regard to the line cross section, it can advantageously be achieved that the electrical resistance and thus the current or the eddy current losses that occur are specifically maximized in a section of the target melting area, so that the support structure is primarily or even exclusively in this section of the target melting area is melted, or the strength in the solid material flowing through is greatly reduced. Thus, both the construction platform and the finished component can remain largely unaffected by the electrical current introduced. Advantageously, therefore, there are no adverse material changes in the construction platform and especially in the finished component, so that in particular the quality of the component can be maintained. This advantage arises regardless of whether the electrical current is supplied to the support structure in a contact-based or contactless manner.

Under certain circumstances, it may be advantageous to use the two previously described embodiments of the detachment method, i. H. to combine the direct and indirect introduction of an electric current to detach a component from at least one support structure or at least one support structure from the construction platform, in particular to carry it out sequentially. For example, in the case of a component with a massive extrusion, the base region of the support structure could initially be weakened locally to such an extent by means of the eddy currents induced by the coil that the mechanical separation of the support structure or the component from the construction platform is facilitated. The component quality is preferably not adversely affected. In a further step, an electrical current could be fed directly to the support structure separated from the building platform, preferably by means of a contact element, in order to melt or melt the target melting area of the support structure and thus separate the support structure from the component.

To optimize the detachment method according to the invention, the support structure to be produced can be modeled before and / or during the production of the component or the support structure in accordance with predefinable process-optimizing criteria, as will be explained below. Such modeling could e.g. B. with the help of a support structure data calculation module, such as a computer equipped with appropriate calculation software.

A first process-optimizing criterion could be the determination of a suitable minimum line cross section of the target melting range. On the one hand, the most efficient or fast melting or melting of the target melting range can be taken into account here. At the same time, however, it could also be taken into account that there is sufficient stability and functionality of the target melting area or of the support structure, the stresses occurring in the component to be manufactured during the manufacturing process in particular being counteracted as comprehensively as possible. As mentioned, the line cross section of the target melting area should preferably be smaller than the line cross section of the base area of the support structure.

Adequate heat dissipation from the component to be produced through the predetermined melting area or the support structure could play a role as a further criterion. In addition to the line cross-section, the configuration of the connection surfaces of the melting bodies in the area of the respective contact points can also be important, in particular with regard to the melting behavior, the heat dissipation and the resilience to mechanical loads. Likewise, the type of construction material and the geometry or design of the component to be produced could also be used when determining a minimum Line cross-section as well as when modeling the target melting range.

Typically, an average dimension (e.g. diameter or width) of a cross section of a melting body can be at least 0.05 mm, preferably at least 0.1 mm, particularly preferably at least 0.2 mm, but at most 1 mm, preferably at most 0.5 mm , particularly preferably at most 0.3 mm.

As a result of the modeling of the support structure, the predetermined melting area or the individual melting bodies can have a different type of line cross section along their longitudinal extent, as mentioned. The target melting area of a support structure preferably has a material cross section or line cross section at a contact point of the target melting area with the additive manufacturing product and / or at a contact point with the base area of the support structure, which cross-section is enlarged compared to a minimum material cross section or line cross section of the target melting area, preferably by at least the first , 5 times, particularly preferably twice, in particular three times.

The contact point or connection point corresponds to the area of the target melting area in which there is a direct, preferably material connection between the target melting area and the component or the base area of the support structure. The cross-sectional area of the contact point is also referred to as the connection area.

If the target melting area comprises a plurality of separate melting bodies, the material cross section of each melting body in the respective contact point can accordingly be larger than a minimum material cross section or line cross section of the melting body in question. In other words, the area of the largest line cross section of each melting body can preferably be realized at the respective contact points.

For this purpose, a “melt addition” can particularly preferably be formed in the area of the respective contact points of the melting body or of the target melting area during additive manufacturing. As previously mentioned, such modeling of the target melting range can preferably be carried out by means of a support structure data calculation module.

Analogous to an increase in the line cross section in the area of the melt addition, there can also be a defined partial area or a locally delimitable point of the smallest line cross section within the melt body or the target melting area. This means that the line cross section in this area of the target melting area is reduced compared to other areas of the same target melting area. This area or this point at which the melting of the target melting area preferably or initially takes place is referred to as the separation area or separation point of the target melting area.

The separating region can preferably be arranged in a central region of the target melting region. At least the separation area does not, however, directly or directly adjoin an area of the component, since, as explained above, the line cross section of the target melting area is preferably maximized by the addition of melt in the contact point itself.

Advantageously, after local melting of the target melting area, a small part of the target melting area remains as “melting residue” on the component or on the building platform. The melting residue thus corresponds to the rest of the original target melting range, which was not melted as a result of the electrical current or which has not dissolved.

The target melting range is therefore preferably not melted through in accordance with its entire length, the formation of “welding craters”, ie. H. holes caused by erosion can be prevented in an area of the component, which in turn has a positive effect on the component quality.

The positioning or arrangement of the target melting area and also of the separation area along the main direction of extent of the support structure can preferably be adapted to the specific component, for example with the aid of a support structure data calculation module.

The support structure can preferably be modeled in such a way that the target melting area is arranged in a region of the support structure which is closer to the construction platform than the additive manufacturing product. If the support structure is not connected to the construction platform itself, the target melting area can accordingly lie in an area of the support structure that is closer to the base area of the support structure than to the apical, ie. H. area of the support structure facing the component.

Alternatively, a predetermined melting area can be arranged in such an area of the support structure that is closer to the additive manufacturing product than to the construction platform. Accordingly, the target melting area would be closer to the apical area of the support structure than to the base area of the support structure.

In addition to the positioning of the target melting area, a configuration or geometry of the target melting area or the melting body can also be optimized with the aid of the support structure data calculation module, in particular in such a way that the most efficient and locally limited melting of the target melting area can be achieved. Especially with the inductive supply of the electric current, the spatial configuration, for. B. with regard to a surface contour of the support structure or the target melting area, may be important for maximizing eddy current losses. When designing such an optimized surface contour of the support structure, surface contours with many edges, for example, are advantageous, since eddy currents preferably form there, which lead to heating. This can be achieved, for example, by means of an essentially star-shaped cross section, which is only made up of lines, for example. Based on the model of a hexagon, you can run three lines through the center of the hexagon that connect the opposite corners. Particularly advantageous are those cross sections that deviate from round, approximately circular or elliptical shapes.

In this context, it is conceivable that the configuration of at least one melting body of a single target melting area is different from the other melting bodies of the same target melting area, for example with regard to the line cross section and the geometry. It can thereby be achieved that initially only a limited number of melting bodies are melted as a result of the electric current, other melting bodies of the same target melting range not (yet) being melted or melted on. Advantageously, a connection between the component and the construction platform can initially be loosened, the component still being fixed at a specific position in the construction space.

In a particularly preferred embodiment, the target melting range can have a number of, ie. H. comprise one or more, individual wire-like or cord-shaped melting bodies which are arranged essentially parallel to one another in a region between the base region of the support structure and the component. Such an arrangement of fusible bodies or fusible links is also known as a “forest of thin wires”.

Advantageously, the length of the individual fusible links can be used to determine a distance between the base part of the support structure and the component such that post-processing of the detached component following the additive manufacturing process is made possible, for example in the context of an electroerosive method, as will be explained below.

Depending on the precise design or modeling of the support structure, e.g. B. taking into account the above-mentioned optimization criteria, it can preferably be ensured that the support structure, preferably a predetermined melting area of the supporting structure, is at least partially designed and the melting of the supporting structure takes place in at least a section of the predetermined melting area such that as a result of the melting the support structure forms an eroding electrode in at least one area, preferably in the base area, of the support structure. For this purpose, the support structure can preferably be melted in the target melting area. Alternatively, the support structure can be melted locally in such a way that, in particular as a result of a mechanical severing of the locally weakened support structure, an eroding electrode is formed in a region of the support structure, preferably in the base region of the support structure. As previously explained, the base region of the support structure can preferably be connected to the construction platform or the base plate.

Advantageously, the eroding electrode which forms as a result of the severing of the support structure can be suitable for use in an electroerosive process. The eroding electrode can particularly preferably be used for the erosive removal of melt residues remaining on the component and / or on the construction platform.

The component with the eroding electrode could very particularly preferably be produced in the same manufacturing process in that the support structure is designed in such a way that an eroding electrode is automatically formed when the desired melting area is severed. The melt residues of the component and the base region of the support structure can preferably lie essentially opposite one another, the melt residues on the base region forming the eroding electrode in order to remove the melt residues on the component. For this purpose, the component can preferably be anodized and the tool, i. H. the eroding electrode can be contacted cathodically, for example in the area of the respective contact points.

Electrochemical finishing can thus improve the quality of the additive manufacturing product which has already been produced and has been detached from the building platform or base plate, in particular with regard to the surface quality.

Advantageously, by means of the length of the target melting area or the melting body, which can preferably be implemented in the form of the fusible links explained above, a distance between the eroding electrode which is formed and the fusible residues of the finished component which are to be eroded away are determined. The length of the fusible links can particularly preferably be determined such that the mutually facing surfaces of the component and the eroding electrode are arranged at a distance from one another which is suitable for the electrochemical finishing of the component, for example with an average distance of at least 3 μm, preferably at least 4 μm , but at most 6 µm, preferably at most 5 µm.

Advantageously, the distance between the base region of the support structure or the eroding electrode and the component can be kept constant even after the fusible links have been severed by means of a suitable holding device, in particular during the electrochemical processing of the component. Such a holder device can also be built by means of additive manufacturing, possibly supplemented by contact or insulation points made of an electrically non-conductive material. The base region of the support structure can preferably already be detached from the construction platform before the start of the electrical eroding.

Advantageously, the electrochemical processing of the component can take place in the process chamber in which the component was manufactured, with unconsolidated building material having preferably already been removed from the process chamber, and the component and the eroding electrode being in a dielectric suitable for electroerosion.

If, in an additive manufacturing process, more than just one component was manufactured on the construction platform at the same time, the respective base areas of the support structures can be separated from the construction platform along a separation plane before the start of the electroerosive process, for example by means of the mechanical component (i.e. the separation unit) of the detachment device according to the invention . The individual base areas, which then form the corresponding eroding electrodes with the melt residues remaining on them, can then be used for preferably sequential electrical eroding of the respective components.

Advantageously, such a development of the detachment method according to the invention enables an eroding electrode for electrochemical processing of a component in the course of additive manufacturing to be initially arranged as a support structure of the component to be produced, which is made possible in particular by means of the predefinable length of the target melting range. Thus, the support structure, i.e. H. the later eroding electrode, are already provided during the additive manufacturing process and contribute to increasing the component quality by means of an improvement in the separation and / or post-processing process.

In addition, the eroding electrode enables the surface quality of the component to be optimized as part of a post-treatment of the component following the manufacturing process. For example, the process steps of the preferred detachment method, in particular the detachment of the component from the support structure and the electrochemical processing of the component, can take place in direct succession within the same process chamber in which the additive manufacturing of the component has also taken place. A time-consuming repositioning of the component between different components, for example between the device for additive manufacturing and a device for surface processing, can thus be dispensed with. The time required for the aftertreatment of an additive component after the additive manufacturing can advantageously be shortened as a result.

Particularly preferably, the support structure can at least partially be designed such that after the additive manufacturing product has been detached from the support structure, in particular during or as a result of the melting of the support structure in accordance with the detachment method according to the invention, there is a formation in at least one area of the support structure, preferably in the base area Forms eroding electrode, wherein the eroding electrode can be used for electrical erosion or for eroding away melt residues of the severed desired melting area remaining on the component.

As mentioned above, the support structure can preferably be modeled or shaped in a suitable manner by means of a special calculation module before the additive manufacture, as will be explained below.

For this purpose, the manufacturing device, in particular a control device of the device, can have finished process control data, e.g. B. 3D design data, which can be realized with the help of CAD data, for the production of the component and a number of support structures. For this purpose, the control device can preferably have a memory for an irradiation control protocol with irradiation control data or irradiation control parameters, a control unit, for example a microprocessor or the like, in order to process the irradiation control protocol, as well as corresponding suitable interfaces to the components of the device, such as e.g. B. the radiation source, the mirror system or the scanner or other components, according to the To control the irradiation strategy or the irradiation control protocol, ie to apply suitable control signals to the components.

In addition to information or commands for additive manufacturing of the component, the irradiation control data can also include instructions for manufacturing a number of “standard” support structures, i. H. Support structures that were typically arranged to support the component in the process space in previous manufacturing processes.

The control device can therefore preferably comprise a support structure data calculation module, which is designed so that the support structure to be produced, preferably component-specific, can be recalculated or optimized on the basis of the irradiation control data. Advantageously, e.g. B. a predetermined melting area can be arranged in the support structure such that the support structure can be detached from the component or from the construction platform in accordance with the detachment method according to the invention. Furthermore, the support structure irradiation control data can be calculated in such a way that the production device forms a support structure with a target melting area, at least one area of the support structure having an eroding electrode after the target melting area has melted.

The optimized irradiation control data can then be forwarded to the control unit of the control device, the production device being controlled by the control unit in such a way that the component and the support structure are formed in accordance with the optimized irradiation control data.

In addition, such a control device can also have all known conventional components that have been present in such control devices for devices for additive manufacturing of manufacturing products.

The control device can preferably be implemented in the form of a computer unit with suitable software, in particular the support structure data calculation module can be implemented in the form of suitable software program parts in the computer unit of the control device. For this purpose, the computer unit can have, for example, one or more cooperating microprocessors or the like. A largely software-based implementation has the advantage that even previously used control devices can be easily upgraded by a software or firmware update in order to work in the manner according to the invention.

The control device, in particular the memory device of the control device, can preferably be designed such that a computer program product with a computer program can be loaded therein in order to carry out the individual process steps of a manufacturing method described above when the program is executed in the control device.

Such a computer program product can, in addition to the computer program, optionally additional components such as. B. a documentation and / or additional components, including hardware components such. B. hardware keys (dongles, etc.) for using the software. For transport to the control device and / or for storage on or in the control device or control device, a computer-readable medium, for example a memory stick, a hard disk or another portable or permanently installed data carrier, can be used, on which the program sections readable and executable by a computer unit of the control device can be used of the computer program are stored.

A detachment device according to the invention can, as mentioned at the beginning, be designed in different ways. In addition to the components already explained, the detachment device can comprise a data preparation unit for determining the line cross sections of the individual melting bodies of the relevant support structures. Corresponding 3D design data of the support structures, in particular after optimization by means of the support structure data calculation module, from the additive manufacturing process can be used to calculate the line cross sections, for example. The data processing unit can preferably be implemented in the form of a computing device with suitable software or software program parts.

The data processing unit is preferably designed to determine the electrical current required for complete melting or for local melting of one or more target melting areas and to pass it on as an input variable to a current control unit of the detachment device according to the invention, the calculation for each target melting area, in particular for each melting body, can be carried out separately.

The current control unit in turn can be designed to transmit the electrical current provided by a current source into a region of the component and / or the by means of the modularly positionable contact elements at the corresponding contact points or by means of at least one induction coil of the coupling device Building platform or the base plate and / or the support structure can be introduced to adjust or regulate according to the specified data of the data processing unit. The current source as well as the current control unit can be realized as part of a current application device.

The modularly positionable contact elements of the detachment device according to the invention can preferably be controlled separately, i. H. the contact elements can be individually supplied with electrical current. For this purpose, the detachment device can comprise a computer program product which enables various contact elements to be controlled automatically. Such a computer program product advantageously enables automated, for example sequential, melting or melting of certain support structures.

The detachment device according to the invention preferably comprises a mechanical separation unit for mechanically separating or releasing a connection between the component and the support structure or between the support structure and the construction platform along a predefinable separation plane.

As already explained, it may be necessary for a component with a massive extrusion to be connected to the building platform or the base plate of the production device, it being additionally possible for a number of support structures to be arranged between the component and the building platform.

To detach such a component from the support structure and / or a number of support structures from the construction platform, the mechanical separation unit of the detachment device according to the invention can comprise at least one band saw and a suitable drive device. The mechanical separation unit can preferably be controlled by the previously mentioned computer program product of the detachment device according to the invention, in particular in such a way that mechanical detachment and, on the other hand, electrical melting or melting of at least one target melting area are coordinated or coordinated with one another.

Advantageously, the detachment device according to the invention is suitable for completely and essentially automated, that is, the detachment method according to the invention for detaching an additive manufacturing product from a support structure and / or for detaching the support structure from a construction platform. H. with little manual intervention. Advantageously, a number of support structures of one or more components can be severed or melted locally, mainly simultaneously or sequentially, whereby the time required to remove one or more components from the process space of the device can be reduced.

• 1 eine schematische, teilweise im Schnitt dargestellte Ansicht eines Ausführungsbeispiels einer Vorrichtung zur additiven Fertigung von Fertigungsprodukten als Teil des erfindungsgemäßen Bereitstellungssystems,
• 2 eine schematische Darstellung des Ablösens eines Bauteils von einer Stützstruktur gemäß einer Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 3 ein Ersatzschaltbild zu der in 2 gezeigten Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 4 und 5 eine schematische Darstellung des Ablösens eines Bauteils von einer Stützstruktur gemäß einer weiteren Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 6 eine schematische Darstellung des Ablösens eines Bauteils von einer Stützstruktur gemäß einer dritten Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 7 eine schematische, teilweise im Schnitt dargestellte Ansicht eines Ausführungsbeispiels eines Sollschmelzbereichs gemäß einer Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 8 eine schematische Darstellung des Durchschmelzens des in 7 gezeigten Sollschmelzbereichs gemäß einer Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 9 eine schematische, teilweise im Schnitt dargestellte Ansicht des in 7 und 8 gezeigten und gemäß einer Ausführungsform des erfindungsgemäßen Ablöseverfahrens durchschmolzenen Sollschmelzbereichs,
• 10 eine schematische, teilweise im Schnitt dargestellte Ansicht des in 9 gezeigten durchschmolzenen Sollschmelzbereichs während einer Elektroerodierung gemäß einer Ausführungsform des erfindungsgemäßen Ablöseverfahrens,
• 11 bis 15 schematisch, teilweise im Schnitt dargestellt, verschieden ausgestaltete Sollschmelzbereiche gemäß mehrerer Ausführungsformen des erfindungsgemäßen Ablöseverfahrens,
• 16 eine schematische Darstellung des Durchschmelzens eines Sollschmelzbereichs gemäß einer weiteren Ausführungsform des erfindungsgemäßen Ablöseverfahrens.

The invention is explained in more detail below with reference to the accompanying figures using exemplary embodiments. In the various figures, identical components are provided with identical reference numbers. The figures are generally not to scale. Show it:

• 1 2 shows a schematic view, partially in section, of an exemplary embodiment of a device for additive manufacturing of manufacturing products as part of the provision system according to the invention,
• 2nd 1 shows a schematic illustration of the detachment of a component from a support structure according to an embodiment of the detachment method according to the invention,
• 3rd an equivalent circuit diagram to that in 2nd shown embodiment of the detachment method according to the invention,
• 4th and 5 1 shows a schematic illustration of the detachment of a component from a support structure according to a further embodiment of the detachment method according to the invention,
• 6 1 shows a schematic illustration of the detachment of a component from a support structure according to a third embodiment of the detachment method according to the invention,
• 7 2 shows a schematic view, partly in section, of an exemplary embodiment of a target melting area according to an embodiment of the detachment method according to the invention,
• 8th is a schematic representation of the melting of the in 7 shown melting range according to an embodiment of the detachment method according to the invention,
• 9 is a schematic, partly in section view of the in 7 and 8th shown and melted according to an embodiment of the detachment process according to the invention,
• 10th is a schematic, partly in section view of the in 9 shown melted target melting range during electrical discharge machining according to an embodiment of the stripping method according to the invention,
• 11 to 15 schematically, partially shown in section, differently designed target melting areas according to several embodiments of the detachment method according to the invention,
• 16 a schematic representation of the melting of a target melting area according to a further embodiment of the detachment method according to the invention.

The following embodiments are related to a device 1 for additive manufacturing of manufacturing products 2nd in the form of a laser sintering or laser melting device 1 Described explicitly that the invention is not limited to laser sintering or laser melting devices. The device is therefore briefly referred to below as a “laser sintering device” 1, without any restriction of generality.

Such a laser sintering device 1 is schematically in 1 shown. The device has a process space 3rd or a process chamber 3rd with a chamber wall 4th in which the manufacturing process essentially runs. In the process chamber 3rd there is a container open at the top 5 with a container wall 6 . The top opening of the container 5 forms the current working level 7 . The inside of the opening of the container 5 lying area of this working level 7 is used as construction site 8th referred to and can be used to build the object 2nd be used.

The container 5 points one in a vertical direction V movable base plate 11 on that on a support 10th is arranged. The base plate 11 closes the container 5 downwards and thus forms its bottom. The base plate 11 can be integral with the carrier 10th be formed, but it can also be separated from the carrier 10th be formed plate and on the carrier 10th attached or simply stored on top. On the base plate 11 can be a build platform 12th be attached as a construction document on which the object 2nd is built up. Basically, the object 2nd but also on the base plate 11 be built yourself, which then forms the construction document.

The basic structure of the object 2nd takes place in such a way that a layer of building material is first placed on the building platform 12th is applied, then - as explained later - with a laser at the points which are to form parts of the object to be manufactured, the building material is selectively solidified, then with the aid of the carrier 10th the base plate 11 and thus the construction platform 12th is lowered and a new layer of building material 13 is applied and then selectively solidified, etc. The in 1 on the build platform 12th built object 2nd is below the working level 7 shown in an intermediate state. It already has several solidified layers and is made of unconsolidated building material 13 surround. As construction material 13 Various electrically conductive materials, preferably powder, can be used. Metallic construction materials as well as self-conducting or intrinsically conductive plastics are preferably used, but also those plastics which obtain electrical conductivity by adding electrically conductive fillers.

In a storage container 14 the laser sintering device 1 there is fresh construction material 15 . Using one in a horizontal direction H movable coater 16 can the building material 15 at the working level 7 or within the construction area 8th be applied in the form of a thin layer.

In the process chamber 3rd there is optionally a radiant heater 17th . This can be used to heat the freshly applied building material 15 serve, essentially the building material 15 in the entire construction area 8th is heated. The one from the heater 17th The amount of basic energy introduced into the building material is below the necessary energy at which the building material sinters or even melts.

The laser sintering device has for selective solidification 1 a solidification device 20th on, which here in the form of an irradiation device 20th with a laser 21 is realized. The laser 21 generates a laser beam 22 , which has a deflection device 23 is deflected so as to selectively introduce energy into the respectively selectively solidified regions of the layer in accordance with a predetermined radiation strategy. This laser beam continues 22 through a focusing device 24th to the working level 7 appropriately focused. The radiation device 20th is preferably located outside the process chamber 3rd and the laser beam 22 is about one at the top of the process chamber 3rd in the chamber wall 4th attached coupling window 25th into the process chamber 3rd directed and meets the working level at a certain point 7 , ie the layer currently to be consolidated.

The radiation device 20th can include not just one but several lasers, for example. Preferably, this can be gas or solid-state lasers or any other type of laser such as. B. act laser diodes, in particular VCSEL (Vertical Cavity Surface Emitting Laser) or VECSEL (Vertical External Cavity Surface Emitting Laser) or a line of these lasers.

The laser sintering device 1 also contains (optionally, also below) a sensor arrangement 35 , which is suitable for one during the impingement of the laser beam 22 on the building material 15 at the working level 7 process radiation emitted. This sensor arrangement 35 works in a spatially resolved manner, ie it is able to record a kind of emission image of the respective layer. Preferably as a sensor arrangement 35 an image sensor or a camera is used which is sufficiently sensitive in the area of the emitted radiation. Alternatively or additionally, one or more sensors could also be used to detect optical and / or thermal process radiation, e.g. B. photodiodes, which from a molten bath under incident laser beam 22 Detect emitted electromagnetic radiation, or temperature sensors for detecting an emitted thermal radiation. The one from the sensor array 35 captured signals are used as a process space sensor data set SDS here to a control device 30th the laser sintering device 1 pass, which also serves the various components of the laser sintering device 1 to control the entire control of the additive manufacturing process.

The control device 30th includes a support structure data calculation module 34 , which calculates or optimizes an irradiation strategy for the layered manufacture of the additive component, including an irradiation strategy for the layered manufacture of a number of support structures. Alternatively, the support structure data calculation module can also be signaled with the control device 30th be permanently or temporarily connected. Process control data serve as input parameters PS (e.g. 3D design data), which include at least the corresponding control data for the selective solidification of the individual component layers. The process control data can preferably PS also include control data for additive manufacturing of the support structures, which is then optionally available from the support structure data calculation module 34 if necessary, can be modified or optimized with regard to the later removability with a method according to the invention. Alternatively, the support structure control data can also first be generated using the support structure data calculation module 34 be calculated.

To optimize the radiation strategy, the support structure control data can be calculated by the support structure data calculation module 34 modified and / or calculated, in particular model-specifically, so that according to the radiation strategy from the building material 15 the component 2nd and at least one firmly connected support structure (in 1 not shown, see 2nd ) is built, the support structure by the device 1 is formed in such a way that the support structure has at least one predetermined melting area, it being possible for the component to be detached from the support structure and / or the support structure from a construction platform in accordance with the detachment method according to the invention.

The control device 30th is constructed so that the laser sintering device 1 , in particular the radiation device 20th , by a control unit 29 according to that previously using the support structure data calculation module 34 calculated or optimized radiation strategy is controlled. The control unit controls this 29 in the usual way the components of the radiation device 20th , namely the laser here 21 , the deflection device 23 and the focusing device 24th and for this purpose transfers the radiation control data accordingly BS . The control unit 29 also controls using suitable heating control data HS the radiant heating 17th using coating control data ST the coater 16 and by means of carrier control data TS the movement of the wearer 10th .

Optionally, the control device 30th another control device 31 include which using process control data PS and the process space sensor data set SDS or other suitable process data quality data QD determined, for example in a variant to the control unit 29 can be transferred in order to be taken into account in the radiation strategy and thus to be able to intervene in the additive manufacturing process.

The control device 30th is here z. B. on a bus 36 or another data connection, with a terminal 40 coupled with a display or the like. Via this terminal 40 an operator can control the device 30th and thus the entire laser sintering device 1 Taxes. In particular, the display of the terminal 40 also during the ongoing manufacturing process to visualize the radiation strategy for manufacturing the component 2nd or the support structures and / or the process space sensor data record SDS and / or the quality data QD can be used.

In addition to the laser sintering device 1 is in 1 an exemplary embodiment of a detachment device according to the invention as a block diagram 37 shown. The detachment device 37 here comprises a mechanical separation unit 54 , a current application device 38 with an electrical power source 56 and a current control unit 57 and a data processing unit 71 . The detachment device 37 can also include other components, as will be explained in detail in the following description of the figures. In the embodiment shown here, the detachment device 37 over a bus 36 with the components of the laser sintering device explained above 1 connected to the detachment device 37 e.g. B. the data on the components, in particular the geometry of the support structures and the predetermined melting areas, the specific resistance of the Materials etc., receives and thus z. B. can determine the required voltages or currents.

At this point, it is again pointed out that the present invention does not apply to such a laser sintering device 1 is limited. It can be applied to any other method for the generative or additive production of a three-dimensional object by, in particular in layers, applying and selectively solidifying a building material, wherein an energy beam for solidifying is emitted onto the building material to be solidified. Accordingly, the radiation device can not only be a laser, as described here, but any device could be used with which energy as wave or particle radiation can be selectively applied to or into the building material. For example, instead of a laser, another light source, e.g. B. an electron beam, etc. can be used.

In 2nd a first embodiment of the detachment method according to the invention is shown. An additive component 2nd is by means of a one-piece support structure 50 to a construction platform 12th connected to the device for additive manufacturing. Alternatively, the support structure could be 50 also be connected to a base plate (not shown here) of the device. In this exemplary embodiment, the support structure comprises 50 a "block-like" base area 52 the support structure and in the direction of the component 2nd towards a "branched" target melting range 51 . The target melting range 51 here comprises a plurality of individual melting bodies formed essentially parallel to one another 65 .

The melting body 65 the support structure 50 are fixed, in particular by means of a material bond, to an area of the component 2nd tied up. In this embodiment, the target melting range 51 in such an area of the support structure 50 arranged, the additive component 2nd is closer than the build platform 12th or the base plate of the device. The construction platform 12th the device is fixed, again preferably by means of a material bond, to the base area 52 the support structure 50 tied up.

For detaching the additive component 2nd from the support structure 50 can be in an area of the component 2nd as well as the construction platform 12th a voltage is applied so that an electric current flows at least between these two areas. The voltage is preferably at defined contact points 59 , 59 ' namely by means of modularly positioned contact elements 66 , 66 ' the current application device according to the invention 38 created. To establish a direct, contact-based connection between the contact point 59 , 59 ' and contact element 66 , 66 ' , the contact point 59 (here on the component 2nd ) z. B. with the help of a "contact flag" 59 be realized, the corresponding contact element 66 using a crocodile clip 66 or the like can be realized. In the area of the construction platform 12th is the contact point 59 ' with the help of a socket 59 ' and the contact element 66 ' using a form-fitting connector 66 ' , e.g. B. a banana plug, realized. The contact elements 66 , 66 ' are directly wired to an external power source 56 connected.

In the exemplary embodiment shown here, the electrical circuit thus includes the additive component 2nd , the support structure 50 as well as the build platform 12th . An electrical resistor is preferred R2 of the target melting range 51 greater than an electrical resistance R1 of the additive component 2nd and also as an electrical resistor R3 of the base area 52 the support structure (see also the equivalent circuit diagram in 3rd , where R2 »R1 and R2» R3). In other words, the greatest electrical resistance R2 of the electrical circuit in the area of the target melting range 51 the support structure realized. Maximizing the electrical resistance may be preferred R2 can be achieved in that the material cross section or the line cross section of the target melting area 51 compared to a material cross section of the additive component 2nd or the base area 52 the support structure is reduced.

Preferably the power source 56 with a control unit 57 , preferably a current control unit 57 , coupled ( 2nd ). The electricity control unit 57 can also be part of the power source 56 be trained, or be integrated into it. The current control unit is preferred 57 trained the power source 56 to control so that the current in the target melting range 51 as described is so large that the target melting range 51 is completely melted or severed as a result of the electric current. Alternatively, the supplied electrical current can only lead to local melting, so that the component is detached 2nd from the support structure 50 mechanical work is still necessary. As previously explained, the power source 56 who have favourited Electricity Control Unit 57 as well as the corresponding coupling devices ( 66 , 66 ' ) as part of the power application device 38 (please refer 2nd ) be realized.

After melting or cutting through the target melting range 51 can the additive component 2nd can be removed from the process space of the device for further post-processing (not shown here). Preferably, the current control unit 57 with a data processing unit 71 be coupled (see 1 ), the data processing unit 71 is designed for this purpose, the electrical current required for complete melting or for melting the target melting range 51 the support structure 50 is required to determine and as an input variable to the current control unit 57 pass on. The determination of the required current strength by the data processing unit 71 can in turn take place on the basis of corresponding 3D construction data of the support structures, for example from the support structure data calculation module 34 can be provided (see 1 ). It is of particular importance here, as previously in conjunction with 3rd explained, a minimum line cross-section or material cross-section of the individual fuses 65 , or the sum of the wire cross-sections of the melting body 65 resulting line cross section of the target melting range 51 .

The data processing unit 71 as well as the current control unit 57 , the power source 56 and the modularly positioned contact elements 66 , 66 ' are here as part of the detachment device according to the invention 37 realized (see 1 ).

4th shows a further embodiment of the detachment method according to the invention, wherein the additive component 2nd here using a component 2nd self-owned massive vertical extrusion 9 directly to the construction platform 12th is connected. In addition, the additive component 2nd by means of two separate support structures 50 , 50 ' directly to the construction platform 12th tied up. The support structures 50 , 50 ' each include a base area 52 , 52 ' as well as a target melting range 51 , 51 ' , with the respective target melting range 51 , 51 ' a number of individual melting bodies 65 , 65 ' includes.

Due to the direct connection of the additive component 2nd to the construction platform 12th in the field of extrusion 9 the component here 2nd initially mechanically from the build platform 12th be separated. The separation can preferably be carried out by means of a mechanical separation unit 54 done, for example, one or more band saw blades 55 and may include a motion mechanism and a motor (not shown here). The basic areas can also be used for mechanical separation 52 , 52 ' of the support structures 50 , 50 ' be separated from the construction platform. The one on the component 2nd remaining areas of the support structures 50 , 50 ' can be removed from the component in a further step 2nd be replaced as in 5 will be shown.

5 shows the component 2nd with a massive extrusion 9 according to 4th , the component 2nd has already been separated from the construction platform here by means of a mechanical separation unit. To the on the component 2nd remaining areas of the two support structures 50 , 50 ' from the component 2nd can replace the basic areas 52 , 52 ' of the two support structures 50 , 50 ' in the area of contact points 59 ' , 59 " each with a separate contact element 66 ' , 66 " get connected. A region of the additive component can also be used in the same way 2nd , preferably the contact point 59 , with a contact element 66 get connected.

Preferably, the individual modularly positioned contact elements 66 , 66 ' , 66 " can be controlled separately by the detachment device according to the invention, ie they can be individually supplied with electric current.

For this purpose, the removal device according to the invention can be a control program 70 include, for example, with the help of a computer program 70 in the power control unit 57 Could be realized and which is an essentially automated control of the individual contact elements 66 , 66 ' , 66 " enables. It can advantageously be achieved that an electrical voltage initially only at one contact point 59 ' a first support structure 50 (shown on the left in this figure) and on the additive component 2nd is created, with only the two corresponding contact elements 66 , 66 ' be supplied with electrical current. As a result of the electrical current, the target melting range can thus be targeted 51 the support structure shown on the left in this figure 50 melted or weakened locally. In a further step, a contact element can accordingly 66 " in the area of the support structure shown here on the right 50 ' as well as the contact element 66 on the component 2nd be supplied with electrical current to the target melting range 51 ' the support structure 50 ' to melt or weaken locally.

Alternatively, the two contact elements 66 ' , 66 " of the two support structures 50 , 50 ' also be supplied with an electric current at the same time, so that the two predetermined melting areas 51 , 51 ' be melted substantially simultaneously. To the current flow in the area of the contact point 59 on the component 2nd to keep it as low as possible and thus the quality of the finished component 2nd u. To increase the separation of the two support structures 50 , 50 ' from the component 2nd preferably sequential.

6 shows a further embodiment of the detachment method according to the invention. The additive component 2nd is by means of two separate support structures 50 , 50 ' to the construction platform 12th connected, whereby here an electric current in an area of the support structures 50 , 50 ' in the form of eddy currents from the outside and without direct contact between the component 2nd or the construction platform 12th and a current source is induced.

To induce the electrical current in an area of the support structures 50 , 50 ' the points in question are from a single induction coil 58 surround. To regulate the strength of the magnetic field in the Support structures 50 , 50 ' induced electrical current or the induced eddy currents, the induction coil 58 with a current control unit 57 and a power source 56 be coupled. The current control unit preferably controls 57 about the strength of the current flow through the induction coil 58 the strength of the electromagnetic field and thus the current flow through the support structures 50 , 50 ' according to the input data of the aforementioned data processing unit 71 (please refer 1 ), in particular such that at least one area of the support structures 50 , 50 ' completely melted or weakened locally. It should be noted that the induction coil 58 can also completely enclose the process chamber of the device (not shown here) from the outside.

Here too, preference can be given to a special configuration of the support structures 50 , 50 ' the eddy current losses in an area of the support structures 50 , 50 ' , especially in the target melting areas (here from the induction coil 58 covered) of the support structures 50 , 50 ' are maximized in such a way that the target melting areas are completely melted or locally melted due to the corresponding heat development. Such a design or modeling of the support structures 50 can preferably by means of in 1 support structure data calculation module shown 37 respectively.

In this exemplary embodiment of the detachment method according to the invention, the entirety of the support structures is advantageous 50 , 50 ' between the component 2nd and the build platform 12th are arranged, equally comprised of only one alternating electromagnetic field. This means that the formation of separate electrical circuits between a first support structure 50 (shown here on the left) and the component 2nd or between a second support structure 50 ' (shown here on the right) and the additive component 2nd can be dispensed with. This can advantageously reduce the complexity of the detachment process of the additive component 2nd of a number of support structures 50 , 50 ' be further simplified.

The induction coil 58 is here as part of the detachment device according to the invention 37 realized (see 1 ). This can preferably be done by the induction coil 58 generated alternating magnetic field to be spatially limited locally, for example by means of a suitable limiting device. The induction coil is preferred 58 designed and arranged so that at least the component 2nd essentially lies completely outside the heat-affected zone of the alternating magnetic field. That means that within the component 2nd preferably no eddy currents through the coil 58 be generated.

The induction coil can advantageously 58 be vertically adjustable, ie the induction coil 58 can along the length of the support structures 50 , 50 ' be moved vertically. Subsequently, the effective range of the alternating magnetic field or a range of the maximum eddy currents is vertical along the longitudinal extension of the support structures 50 , 50 ' slidable. It is advantageously by means of only one induction coil 58 so possible either the basic areas 52 , 52 ' of the support structures 50 , 50 ' or the predetermined melting areas of the support structures 50 , 50 ' selectively melt or melt locally. Alternatively, a detachment device according to the invention could 37 also a plurality of vertically adjustable induction coils 58 include.

7 is a detailed view of a support structure 50 , in particular a target melting range 51 , according to an embodiment of the detachment method according to the invention, the target melting range 51 here using a number of predominantly parallel fusible links 60 is realized. The melting bridges 60 , which alternatively also as melting struts 60 can be referred to, in this embodiment form the individual melting bodies of the target melting range 51 (please refer 2nd ).

Such a configuration of the target melting area 51 with a number of wire or tube-like fusible links arranged essentially parallel to one another 60 , can also be described as a “forest of thin wires”. In particular, a middle area of the fusible links 60 can have a substantially cylindrical shape. The individual fusible links 60 are in a top apical area at a contact point 61 directly with the additive component 2nd connected. At a lower, basal area opposite the apical area are the fusible links 60 at a contact point 69 firmly with the base area 52 a one-piece support structure 50 connected.

The material cross section or the line cross section of each individual fusible link 60 is at the respective contact points 61 , 69 compared to a minimal line cross-section of the relevant fusible link 60 enlarged. As a result of this material addition at the contact points 61 , 69 Which material addition is also referred to as “melt addition” is the range of the minimum line cross section or the minimum material cross section of the fusible links 60 , which likewise corresponds to the area of the highest electrical resistance, preferably in a central area of the fusible links 60 arranged. This area of greatest electrical resistance, in which the support structure 50 is melted or cut as a result of the electric current, can also be used as a separation area of the support structure 50 or the Target melting range 51 be referred to (see 16 ).

To damage the component 2nd during separation from the support structure 50 to avoid the dividing area 68 not directly to the component 2nd where the contact point between the target melting range 51 and component 2nd with the help of a melt addition 64 is realized. This is particularly in 16 clear. As a result of the electric current, the target melting range melts 51 preferably in the area of the separation area 68 completely on or is weakened locally. After cutting through the target melting range 51 remains - as in 16 shown on the right - a melt residue in the melt addition area 63 on the detached component 2nd , with a "melting crater" 67 , ie a hole or a cavity in the component 2nd is avoided.

In 8th is the target melting range 51 out 7 shown, the target melting range 51 is melted or melted here according to an embodiment of the detachment method according to the invention. This is the additive component 2nd as well as the base area 52 by means of contact elements 66 , 66 ' an electrical current is supplied directly, the contact elements 66 , 66 ' with a power source 56 or a current control unit 57 are connected.

The individual fusible links heat up as a result of the electrical current 60 , in particular in a region of the minimum line cross section, particularly strong, so that the target melting range 51 is melted completely or melted locally similar to a fuse.

9 shows the target melting range 51 according to the 7 and 8th , with the target melting range 51 has already been completely melted here by means of an embodiment of the detachment method according to the invention. The originally in the target melting range 51 arranged fusible links were completely melted due to the electric current, ie essentially according to their entire length, with no direct or fixed connection between the component 2nd and the base area 52 the support structure 50 more exists, so the component 2nd can be removed from the process space of the device.

After melting through the target melting range 51 only in one area of the melt addition, ie for each individual melted melt web, does a melt residue remain 63 on the additive component 2nd or at the base area 52 the support structure 50 . The base-like melting residues 63 represent the remains of those originally in the target melting range 51 arranged fusible links. This melt residue 63 on the component 2nd can now advantageously be removed by means of an electroerosive process, the melt residues being preferred 63 at the base area 52 the support structure 50 can be used. This is shown schematically in 10th shown.

For EDM machining of the component 2nd the support structure 50 , especially the base area 52 the support structure 50 , are formed in a manufacturing process in such a way that, as a result of the previously explained melting of the target melting range according to the invention 51 an eroding electrode 62 in the base area 52 the support structure 50 trains.

For electrical eroding on the component 2nd remaining enamel residues 63 can the additive component 2nd and the base area 52 the support structure by means of contact elements 66 , 66 ' with an external power source 56 or a current control unit 57 get connected. The eroding electrode is preferably used 62 , ie the base area 52 , cathodically contacted while the additive component 2nd is anodically contacted. For erosion of enamel residues 63 from the additive component 2nd can the two electrodes, ie the component 2nd and the base area 52 , be arranged in a suitable non-conductive medium or a dielectric (not shown here).

A vertical distance between the component 2nd and the base area 52 or the eroding electrode 62 can by the longitudinal extent of the target melting range 51 , especially by the length of the fusible links (see 7 ) can be determined. According to a manufacturing method according to the invention, the component 2nd and the eroding electrode 62 are already formed during the additive manufacturing with a distance from one another that is suitable for electrical eroding. At this preferred distance between the component 2nd and the eroding electrode 62 also during electrical discharge machining, ie after the target melting range has melted 51 can maintain the component 2nd and / or the eroding electrode 62 be connected to a suitable holding device (not shown here).

In the 11 to 15 different configurations of support structures or target melting areas are shown schematically, which can be melted or locally melted by means of the detachment method according to the invention.

11 shows in detail an embodiment of a one-piece support structure 50 . The support structure 50 comprises a “grid-like” or “grid-like” base area 52 , the individual inner walls according to a predetermined constant grid size are arranged. The outer walls as well as some of the inner walls of the base area 52 are extended, at least in sections, vertically in the direction of the component (not shown here) and thus form the target melting area 51 . The target melting range 51 is here by means of a number of wall-like melting bodies formed from relatively thin surfaces 65 realized with a tapering, pyramid-shaped contour, the melting body 65 simply as part of the walls of the grate-like base area 52 are extended upwards. The individual melting bodies 65 are thus in a basal area to the common base area 52 tied up. The base area 52 the support structure 50 opposite upper or apical part of the enamel body 65 , which is the connection surface of the support structure 50 realized on the component, is designed here in the form of a narrow support or bar. For the sake of clarity, the melting bodies are 65 here only on some of the inner walls of the base area 52 , which could alternatively be formed by means of support or cross bars. However, basically everyone can be inside the base area 52 lying inner walls or support rods at the formation of the target melting area 51 be involved.

As an alternative to this, the connection surface could also have a different geometry, as in FIGS 12th to 15 will be shown. As previously explained, the melting bodies described in more detail below could be connected in a basal region to the base region of a support structure and in an apical region to the component.

The in 12th shown melting body 65 is characterized by an almost cylindrical geometry. Accordingly, the connection surface of the target melting area to the component would be essentially circular.

In the 13 is a melting body 65 shown, which has an approximately cruciform cross-section. The connecting surface of the melting body would be corresponding 65 realized on the component here by means of two crossed beams or four "spokes".

The melting body 65 in 14 comprises six essentially "spokes" arranged in a star shape. Deviating from the embodiments shown here, the connection surface could also, for. B. include only a single "spoke".

Other possible forms are in 15 shown. So can the melting body 65 also have a cylindrical, conical or a hollow conical configuration. It is also conceivable that a melting body 65 is formed in the form of a hemisphere between the component and the base region of the support structure. As previously explained, the configuration of the target melting range, in particular with regard to the number and configuration of the individual melting bodies, can be determined on a component-specific basis. The detachment method according to the invention is therefore not limited to a specific configuration of the melting body or the support structure.

Finally, it is pointed out once again that the figures described in detail above are merely exemplary embodiments which can be modified in various ways by a person skilled in the art without departing from the scope of the invention. Furthermore, the use of the indefinite articles "a" or "an" does not rule out that the relevant features can also be present more than once. Likewise, the term “unit” does not rule out the fact that it consists of several interacting sub-components, which may also be spatially distributed.

Reference list

1

Additive manufacturing device / laser sintering device

2nd

Additive manufacturing product

3rd

Process room / process chamber

4th

Chamber wall

5

container

6

Container wall

7

Working level

8th

Construction site

9

Extrusion

10th

carrier

11

Base plate

12th

Construction platform

13

Construction material (in the container 5 )

14

Storage container

15

Building material (in the storage container 14 )

16

Coater

17th

Radiant heating

20th

Irradiation device / exposure device

21

laser

22

laser beam

23

Deflection device

24th

Focusing device

25th

Coupling window

29

Control unit

30th

Control device

31

Control device

34

Support structure data calculation module

35

Sensor arrangement / camera

36

bus

37

Detachment device

38

Current application device

40

terminal

50, 50 '

Support structure

51, 51 '

Target melting area support structure

52, 52 '

Base area support structure

53

Dividing plane

54

(Mechanical) separation unit

55

Band saw blade

56

Power source

57

Electricity control unit

58

Kitchen sink

59, 59 ', 59 "

Contact point

60

Smelting bridge

61

Contact point

62

EDM electrode

63

Melting residues

64

Melt addition

65, 65 '

Melting body

66, 66 ', 66 "

Contact element

67

Melting crater

68

Separation area / separation point

69

Contact point

70

Control program

71

Data processing unit

V

vertical direction

H

horizontal direction

BS

Irradiation control data

HS

Heating control data

PS

Process control data

ST

Coating control data

TS

Vehicle tax data

SDS

Process space sensor data

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102015207306 [0016]
• WO 2017/029276 A1 [0017]

Claims (13)

Method for detaching an additive manufacturing product (2) from a support structure (50, 50 ') and / or for detaching the support structure (50, 50') from a construction platform (12) using an electrical current in at least one target melting area (51, 51 ') of the support structure (50, 50'), so that the electric current leads to a melting of the support structure (50, 50 ') in at least a section of the target melting area (51, 51'), and optionally further separation steps. Procedure according to Claim 1 , wherein an electrical current of the support structure (50, 50 ') via at least one contact point (59, 59', 59 ") on the additive manufacturing product (2) and / or the support structure (50, 50 ') and / or the construction platform ( 12) is supplied. Procedure according to Claim 1 or 2nd , wherein an electrical current is induced in at least a portion of the support structure (50, 50 ') by the application of an alternating magnetic field. Method according to one of the preceding claims, wherein the target melting area (51, 51 ') of the support structure (50, 50') has a higher electrical resistance, preferably a smaller material cross section, than a base area (52, 52) adjacent to the target melting area (51, 51 ') ') of the support structure (50, 50'), the base region (52, 52 ') preferably comprising at least one contact point (59', 59 ") for supplying an electrical current. Method according to one of the preceding claims, wherein the predetermined melting area (51) has a material cross section at a contact point (61) with the additive manufacturing product (2) and / or at a contact point (69) with the base area (52) of the support structure (50), which is enlarged compared to a minimal material cross section of the target melting area (51). Method according to one of the preceding claims, wherein at least one predetermined melting area (51, 51 ') lies in an area of the support structure (50, 50') which is closer to the construction platform (12) than the additive manufacturing product (2). Method according to one of the preceding claims, wherein at least one predetermined melting area (51, 51 ') lies in an area of the support structure (50, 50') which is closer to the additive manufacturing product (2) than the construction platform (12). Method according to one of the preceding claims, wherein the predetermined melting area (51) comprises a number of melting webs (60), preferably arranged in parallel. Method according to one of the preceding claims, wherein the support structure (50), preferably a predetermined melting area (51) of the supporting structure (50), is at least partially designed in this way and the melting of the supporting structure (50) is carried out in at least a section of the predetermined melting area (51) in this way becomes that when the support structure (50) melts, an eroding electrode (62) is formed in at least one area of the support structure (50). Method for providing an additive manufacturing product (2), the additive manufacturing product (2) being built up from a building material (13, 15) in an additive manufacturing process with a support structure (50, 50 ') connected to the additive manufacturing product (2), whereby the detachment of the additive manufacturing product (2) from the support structure (50, 50 ') and / or the detachment of the support structure (50, 50') from a construction platform (12) in a predetermined melting area (51, 51 ') according to a method of Claims 1 to 9 he follows. Procedure according to Claim 10 , After detaching the additive manufacturing product (2) from the support structure (50), an eroding electrode (62), which has formed in at least one area of the support structure (50) when the support structure (50) melts, for the electrical erosion of the manufactured product ( 2) remaining residues (63) of a melted-down melting area (51) is used. Device (37) for detaching an additive manufacturing product (2) from a support structure (50, 50 ') and / or for detaching the support structure (50, 50') from a construction platform (12) with at least one current application device (38) with a coupling device (56, 57, 58, 66, 66 ', 66 ", 70) for introducing an electrical current into at least a region of the support structure (50, 50') so that the electrical current melts the support structure (50, 50 ' ) in at least a section of a predetermined melting area (51, 51 ') of the support structure (50, 50'), and optionally at least one separation unit (54). System for providing an additive manufacturing product (2), comprising - a manufacturing unit (1) for building an additive manufacturing product (2) in an additive manufacturing process with a support structure (50, 50 ') connected to the additive manufacturing product (2) from a building material ( 13, 15), and - a device (37) according to Claim 12 , in particular for detaching the additive manufacturing product (2) from the support structure (50, 50 ') and / or for detaching the support structure (50, 50') from a construction platform (12) in a predetermined melting range (51, 51 ') according to a method of Claims 1 to 9 .

Images