Patent Application
20220343035
The present invention relates to a method, in particular a computer-implemented method, for dividing a virtual three-dimensional overall model of a body into at least two virtual partial models.
Devices and methods for producing a three-dimensional object are widely known in the prior art. WO 2006/122645 A, for example, discloses a device and a method for producing a three-dimensional object by solidifying layers of a powdery material. The layers are applied to the surface of a working panel by means of a coater.
Such methods generally have the disadvantage that the working panel is limited and therefore only bodies with a limited size can be produced. In order to avoid this disadvantage, it is known to subdivide larger bodies into smaller partial bodies that are printed individually and joined together later. This division weakens the lattice structures. This can adversely affect the mechanical properties of the body to be printed. Furthermore, inaccuracies can arise in the partial bodies during the subsequent joining, so that they cannot be joined together in the best possible manner. In addition, the joining process is usually time-consuming and/or cost-intensive.
The object of the present invention is to eliminate the disadvantages known from the prior art.
The object on which the invention is based is achieved by the features of the independent claims. Further advantageous configurations result from the dependent claims and the drawings.
A method, in particular a computer-implemented method, is proposed for dividing a virtual three-dimensional overall model of a body into at least two virtual partial models. In the process, a virtual three-dimensional separating surface is created for the overall model of the body, which has a three-dimensional cell-conforming shape. The term “cell-conforming” refers to a shape that follows the geometry, shape, exterior surface, and/or contour of unit cells. In the method, the overall model of the body is created with a lattice structure made up of a large number of cells. In this case, the unit cells are preferably replaced by the lattice structure. The overall model is then divided into two partial models along the cell-conforming cut surface. The division takes place in such a way that common struts of the lattice structure, which are both part of at least one cell of one partial model and part of at least one adjacent cell of the other partial model, are divided by means of the cell-conforming separating surface in such a way that the corresponding cells remain whole and/or closed. The cells are therefore not broken up. Instead, all of their struts remain. The partial models thus each have self-contained lattice structures. A very high degree of stability of the partial models and of the overall model can advantageously be achieved in this way. The partial models as well as the overall model can also be formed very easily by this cell-conforming division, since no increased accumulation of material is necessary in the joining area between the two partial models. In addition, surfaces that correspond to one another are created so that the partial models can be precisely positioned and guided with respect to one another.
It is advantageous if the common struts are divided in their respective longitudinal direction. This can ensure that the cells are not broken up, but instead remain whole and/or closed. Advantageously, however, a very high level of stability can be achieved.
It is also advantageous if the common struts are divided in such a way that the parts of the respective common strut each extend without gaps and/or continuously between two nodes of the respective corresponding cell. However, the respective adjacent cells remain whole and/or closed.
Furthermore, it is advantageous if at least one of the common struts is divided in such a way that the respective parts are symmetrical or asymmetrical to one another.
In an advantageous development of the invention, it is advantageous if a three-dimensional virtual base body is provided before the creation of the separating surface. Said body reflects the geometric dimensions of the overall model to be created. In this regard, it is also advantageous if at least one cut surface, in particular a flat, curved and/or kinked surface, is then defined, which divides the base body. It is also advantageous if, in particular, a volume of the base body is subsequently filled with a plurality of whole unit cells. The unit cells essentially include a surface, edges, and a center point.
It is advantageous if the three-dimensional cell-conforming shape of the separating surface is created by an algorithm and/or by means of a cell surface of at least some of the whole unit cells located in the region of the cut surface. As a result, the shape of the separating surface is essentially modeled on the surface of the unit cells adjacent to the cut surface.
In an advantageous development of the invention, at least the whole unit cells located in the region of the cut surface are assigned to one of the two sides of the cut surface in order to create the three-dimensional cell-conforming shape of the separating surface. Each of the two sides of the cut surface is therefore advantageously assigned to a respective unit cell group which has a three-dimensional cell-conforming abutment surface in the region of the cut surface.
It is advantageous if the whole unit cells are assigned to one of the two sides of the cut surface via their center point. Accordingly, the whole unit cells are preferably assigned to the side of the cut surface on which their center point is located.
It is particularly advantageous if the shape of the separating surface is created correspondingly and/or based on the three-dimensional cell-conforming, abutting surface of one of the two unit cell groups, so that the separating surface preferably has a shape that corresponds to the cell surface of the unit cells forming the abutting surface.
When creating the lattice structure, it is advantageous if the unit cells are intersected with an exterior surface of the base body, in particular to form a surface lattice structure.
To create the lattice structure of the overall model, it is advantageous if the unit cells are replaced with struts that extend along the edges of the unit cells. The struts represent bodies with a volume in this regard. These struts can now be divided in a cell-conforming manner, so that the corresponding cells remain whole and/or closed. All struts of a cell thus continue to extend continuously and/or uninterruptedly between the nodal points of the cell.
In an advantageous development of the invention, the method has at least one of the following steps:
It is advantageous if at least one of the above method steps is carried out by a user with a computing unit, in particular a computer program stored thereon and/or artificial intelligence, and/or is carried out by such a computing unit.
Also proposed is a computing unit for dividing a virtual three-dimensional overall model of a body into at least two virtual partial models, in particular by means of a computer program stored thereon and/or artificial intelligence. The arithmetic unit is designed to carry out at least some of the method steps of a method according to the preceding description. It is possible for the features mentioned to be present individually or in any combination.
Also proposed is a computer program and/or artificial intelligence which, when executed by a computing unit, causes said computing unit to carry out at least some of the method steps of a method for dividing a virtual three-dimensional overall model of a body into at least two virtual partial models in accordance with the preceding description. The features mentioned can be present individually or in any combination.
Also proposed is a computer-readable storage medium with an at least partially stored virtual three-dimensional overall model of a body, which is divided into at least two virtual partial models, which was produced by using a method, a computing unit, a computer program and/or artificial intelligence as described above. The features mentioned can be present individually or in any combination.
What is proposed is a production method for producing a body in which a virtual three-dimensional overall model of the body, which is divided into at least two virtual partial models, and/or a virtual three-dimensional production model in the production position of the partial models is produced by using a method according to the preceding description. The features mentioned can be present individually or in any combination. Production data for an additive production device is then created by using the divided, virtual, three-dimensional overall model and/or production model. Finally, using the additive production device, the body is produced on the basis of the production data. The additive production device is preferably a 3D printer.
It is advantageous if partial bodies are produced on the basis of the partial models, wherein at least one of the partial bodies is produced in an additive production process, wherein the at least two partial bodies are exposed to a solvent atmosphere in a chamber, so that a surface of the partial bodies is smoothed, and that the at least two partial bodies are placed into the chamber in such a way that they touch at least one joining surface and the solvent atmosphere thus forms a material connection between the at least two partial bodies on the at least one joining surface.
A body is proposed which is produced by using a production method in accordance with the preceding description. It is possible for the features mentioned to be present individually or in any combination.
Furthermore, a device with a computing unit is proposed for creating a virtual three-dimensional overall model of a body, and/or using an additive production device to produce the body. The computing unit is designed to carry out at least some of the method steps of a method for creating a virtual three-dimensional overall model of the body according to the preceding description. It is possible for the features mentioned to be present individually or in any combination.
In addition or as an alternative to the above devices and methods, the following methods and devices are proposed, which can be combined with the above devices and/or methods as desired. A method, in particular a computer-implemented method, is proposed for creating a virtual three-dimensional production model of a body. A virtual three-dimensional production model is to be understood as a model that is used for the creation and/or production of the body, in particular by a device with an additive production device.
In the method, at least one external dimension of a virtual three-dimensional overall model of the body is compared to at least one corresponding internal dimension of a limited production area of an additive production device in at least one spatial direction. The virtual three-dimensional overall model can be a CAD model, for example. The overall model represents the virtual image of the body to be produced. The overall model of the body can be created manually by a user and/or determined automatically by a computing unit.
The production area is the region in which the body can then be at least partially produced. The respective internal dimension of the production area in each spatial direction limits the maximum external dimension of the overall model that can be produced in this spatial direction. Each of the external dimensions of the virtual three-dimensional overall model of the body is preferably compared with each of the corresponding internal dimensions of the limited production area of the additive production device in the respective spatial directions, i.e., in the longitudinal, transverse and vertical directions. This ensures that the body can be produced in the limited production area.
If the external dimensions of the overall model exceed the corresponding internal dimensions of the production area, the overall model is divided into at least two virtual three-dimensional partial models. This division can take place according to a method and/or a device according to the preceding description. It is possible for the features mentioned to be present individually or in any combination. At least one connecting element is then formed, which connects the at least two partial models with one another in such a movable manner that they can be moved relative to one another from a production position in which corresponding joining surfaces of the partial models are spaced apart from one another or a joining position in which the corresponding joining surfaces of the partial models abut one another.
The production position is to be understood as the position in which the at least two partial models can, together with their connecting connection element, be placed within the production area and be produced with the aid of the production device. The partial models are virtual three-dimensional models of parts of the body. On the other hand, the joining position is to be understood as the position in which the at least two partial models abut one another by means of the joining surfaces in such a way that they form the at least one external dimension of the overall model. In this case, the joining surfaces are the surfaces that produce the connection between the at least two partial models in the joining position.
The virtual three-dimensional production model is then created in the production position of the partial models. The virtual three-dimensional production model of the partial models can be used for subsequent additive production within the limited production area of the additive production device. The production model of the body advantageously comprises the overall model and the connecting element in the joining position.
The method has the advantage that the overall model can be produced within the limited production area, although at least one of the external dimensions protrudes beyond the corresponding internal dimension of the limited production area. The overall model is therefore too large for the production area in at least one of the spatial directions. The connecting element connects the at least two partial models so that they can be printed independently of one another in the production position and moved into the joining position after production. This means that overall models or bodies that exceed the limited production area can be produced as well.
The at least one connecting element can also ensure that the joining surfaces of the respective partial models abut one another in the joining position. The respective partial models are produced together, in particular one after the other and/or one above the other, in the production area. The partial models are connected to one another by means of the at least one connecting element in such a way that even if the production parameters change, for example if there are temperature fluctuations, they can be produced to correspond to one another or be dimensionally stable.
It is advantageous if the connecting element is designed in such a way that it connects the at least two partial models to one another in such a way that they are rotatably or translationally movable, in particular that they can be folded and/or displaced relative to one another, wherein the connecting element is preferably designed as a connecting joint, in particular a rotary joint and/or sliding joint. The at least two partial models can be folded and/or displaced from the production position to the joining position and/or vice versa. The connecting joint thus creates a simple and functional connection between the at least two partial models. The connecting element can be designed as a joint, for example as a separable and/or as an inseparable hinge. If the hinge is designed to be separable, then each of the partial models comprises a hinge section which are separably connected to one another. If the hinge is designed to be inseparable, it can be arranged, for example, as a film hinge as a thin region between the at least two partial models. If the connecting element is produced together with the partial models, it can be made of the same and/or a different material than the partial models.
Furthermore, it is advantageous if at least one locking element is formed, by means of which two corresponding partial models can be locked in relation to one another in their joining position. The at least one locking element can thus prevent the at least two corresponding partial models from being moved from the joining position back to the production position. In addition, with the aid of the locking element and the associated holding of the partial models in the joining position of the at least two corresponding partial models, the joining of parts of the body to form the body subsequent to the production can be facilitated.
It is also advantageous if at least one external dimension of at least one of the partial models and/or the production model in the production position is compared with the at least one corresponding internal dimension of the limited production area in at least one of the spatial directions. It can thereby be ensured that the at least one partial model in the production position and/or the production model is arranged in particular exclusively within the delimited production area and can therefore be produced.
The at least one partial model is then advantageously divided into at least two partial models or sub-partial models if the external dimensions of the adjusted partial model and/or the production model exceed the corresponding internal dimensions of the production area. At least one connecting element and/or locking element can then be formed between the at least two sub-partial models and/or the virtual production model can be created in the production position of the partial models and sub-partial models. Thus, if the external dimension is exceeded, at least one of the partial models can be further divided by the at least one corresponding internal dimension of the limited production area. The at least one connecting element arranged on the sub-partial models ensures that the at least two sub-partial models are moved from the production position to the joining position and/or vice versa.
In an advantageous development, the overall model, the partial model and/or the sub-partial model is divided in such a way that its external dimensions are smaller than the corresponding internal dimensions of the production area. This ensures that the production model can be produced within the limited production area. In addition, an unnecessary further division of the overall model, the partial model and/or the sub-partial model can be avoided if its external dimensions are already smaller than the corresponding internal dimensions of the production area.
Furthermore, it is advantageous if the at least one external dimension of the virtual three-dimensional overall model of the body, the at least one partial model and/or the production model is recorded in at least one spatial direction. In addition, it is advantageous if the at least one internal dimension of the delimited production area of the additive production device is entered and/or determined in at least one spatial direction. At least one of the aforementioned steps of detecting the external dimensions, entering and/or determining the internal dimensions can be performed manually by a user and/or determined automatically by a computing unit. This ensures that the at least one external dimension and/or internal dimension is available for carrying out the method.
In addition, it is advantageous if at least some of the method steps, in particular the adjustment and the division, are carried out iteratively until the production model fits completely into the production area. It can thus be ensured that the production model can be produced with the production device following the iterative method. The iterative method represents a very simple way of making the production model manufacturable.
Advantageously, after the at least one external dimension has been compared with the at least one internal dimension and/or before the division into at least two partial models and/or sub-partial models, at least two of the external dimensions of the overall model and/or the partial model are exchanged with at least two of the internal dimensions of the production area. By exchanging at least two of the external dimensions with at least two of the internal dimensions, the overall model and/or the partial model is rotated in the production area. If at least one additional external dimension of the overall model exceeds a corresponding additional internal dimension of the production area in one of the spatial directions, at least one method step, in particular the comparison and the division, can be eliminated due to the exchange. Additionally or alternatively, the exchange, in particular together with the adjustment and/or the division, can be carried out iteratively until the production model fits completely into the production area.
Furthermore, it is advantageous if, after the at least one external dimension has been compared to the at least one internal dimension and before the division into at least two partial models and/or sub-partial models, at least one external dimension of the production model resulting from the division is compared to the internal dimension of the production area. When the connecting element is divided and then formed, at least one of the external dimensions is reduced in one of the spatial directions, as a result of which another external dimension is increased in another spatial direction. By comparing the resulting external dimensions of the production model to the internal dimensions of the production area, it can thus be estimated before the division whether all external dimensions fit into the internal dimensions and whether the production model can therefore be produced in the production device. As a resuit, unnecessary process steps can be avoided.
Furthermore, it is advantageous if at least one of the method steps is carried out by a user with a computing unit, in particular a computer program stored thereon and/or an artificial intelligence, and/or by such a computing unit. In addition or as an alternative to the iterative process described above, the production model can be designed to be manufacturable quickly and/or with as few method steps as possible with the aid of artificial intelligence. Artificial intelligence can intervene in the course of the method in such a way that as few method steps as possible are used and/or the method steps are carried out with the least effort. In addition, an unnecessary division of the overall model, the partial model and/or the sub-part model can be avoided.
What is also proposed is a computing unit for creating a virtual three-dimensional production model of a body, in particular with a computer program and/or artificial intelligence stored thereon. The computing unit is designed to carry out at least some of the method steps of a method for creating a virtual three-dimensional production model of a body according to the preceding description. It is possible for the features mentioned to be present individually or in any combination. The computing unit can comprise an input interface for detecting, inputting and/or determining the at least one external dimension and/or internal dimension. Thus, data, in particular geometrical data of the body and/or the production device, can be entered into the computing unit from external input devices and/or by a user. Additionally or alternatively, the processing unit can have an output interface for outputting the production data to a production device and/or to a computer-readable storage medium.
What is also proposed is a computer program and/or artificial intelligence which, when executed by a computing unit, causes said program or artificial intelligence to carry out at least some of the method steps of a method for creating a virtual three-dimensional production model of a body according to the preceding description. The features mentioned can be present individually or in any combination.
What is also proposed is a computer-readable storage medium, in particular a data memory with a virtual three-dimensional production model stored on it, which was produced by using a method, a computing unit, a computer program and/or artificial intelligence according to the preceding description. The features mentioned can be present individually or in any combination. A computer-readable storage medium is to be understood in this regard as a medium that stores the production model and/or can be read in a device described below. The computer-readable storage medium can be a flash memory, a hard disk, a cloud and/or an optical memory, for example.
A production method for producing a body is proposed as well. In the production method, a virtual three-dimensional production model of the body is created by using a method according to the preceding description. It is possible for the features mentioned to be present individually or in any combination.
Subsequently, production data for an additive production device, in particular a 3D printing device, is created by using the virtual three-dimensional production model. The production data is formed from the production model and can contain additional information about the production. The body is then produced in a limited production area of the additive production device using the production data, wherein the body is produced in multiple parts in the form of a plurality of parts which are movably connected to one another via at least one connecting element and which are in a production position in which the corresponding joining surfaces of the parts are spaced apart from one another. The connected parts of the body reproduce the virtual three-dimensional partial models in finished form. The at least two parts of the body are connected to one another in a positive and/or non-positive manner by means of the connecting element in such a way that they can move relative to one another. The connecting element is advantageously designed as a connecting joint.
It is advantageous if parts of the body are moved from the production position into a joining position in which the corresponding joining surfaces of the parts abut one another.
Furthermore, it is advantageous if parts of the body are locked in the joining position, in particular via at least one locking element that is also produced by the additive production device. The locking element can thus prevent the at least two parts of the body from being moved from the joining position back to the production position. The at least one locking element can be a clip and/or a latching element, for example.
In addition, with the aid of the locking element and the associated holding of the partial models in the joining position of the at least two corresponding partial models, the joining of parts of the body to form the body subsequent to the production can be facilitated.
Furthermore, it is advantageous if the body is exposed to a solvent atmosphere in the joining position, so that a surface of the body is smoothed and/or the at least two parts of the body are positively connected to one another in the region of their abutting joining surfaces.
In addition, it is advantageous if, in particular after the parts of the body have been connected to one another, the connecting element and/or the locking element is at least partially removed. As a result, the body can be brought into its originally intended shape, which is depicted in the overall model.
It is also advantageous if the body is produced by using a powder-based 3D printing process. Powder-based 3D printing processes often comprise the limited production area. In addition or as an alternative, a powder application unit and/or an irradiation unit can also be limited to this production area with regard to their effective area. The method can thus also be used to produce large bodies in such printing methods large bodies in a simplified manner. With such a powder-based 3D printing method, powder materials made of plastic, metal, glass, ceramic and/or composite materials can be used. If plastic is used as the powder material, the 3D printing process is referred to as SLS. It is advantageous if the body is made from an elastomer, in particular TPU.
In an advantageous embodiment, at least one of the parts is produced with a lattice structure. If at least one of the parts of the body comprises lattice bars of the lattice structure on at least one of the joining surfaces, the connecting element and/or the locking element can be arranged on these lattice bars. Likewise, the parts of the body in the region of the lattice bars can be joined together at their joining surfaces.
Furthermore, a body, in particular a component, is proposed. The body is produced by using a production method as described above. It is possible for the features mentioned to be present individually or in any combination.
A device is proposed as well. The device advantageously comprises a computing unit for creating a virtual three-dimensional production model of a body. Additionally or alternatively, the device comprises an additive production device for the production of the body. In addition or as an alternative, the device comprises a chamber for smoothing a surface of the body and/or for positively connecting two parts of the body by means of a solvent atmosphere.
The computing unit is preferably designed to carry out at least some of the method steps of a method for creating a virtual three-dimensional production model of a body according to the preceding description. It is possible for the features mentioned to be present individually or in any combination. Additionally or alternatively, the additive production device and/or the chamber is designed to carry out at least some of the method steps of a production method for the production of a body according to the preceding description. It is possible for the features mentioned to be present individually or in any combination.
In the method for producing a composite body from at least two partial bodies produced in an additive production process, it is additionally or alternatively to the methods and/or devices above, it is advantageous if the at least two partial bodies are exposed to a solvent atmosphere in a chamber, so that one surface of the partial bodies is smoothed. It is advantageous, if the at least two partial bodies are placed in the chamber in such a way that they touch at least one joining surface and that the solvent atmosphere creates a material connection between the at least two partial bodies on the at least one joining surface. According to the above description, the at least two partial bodies can have been produced by using an overall model of the body, which was divided into at least two virtual partial models in a cell-conforming manner. Additionally or alternatively, these can have been produced by using a production model of a production position according to the preceding description. The features mentioned above can be present individually or in any combination.
The solvent atmosphere at least partially dissolves chemical bonds on the surface of the partial bodies. As a result, the molecules on the surface can rearrange themselves or are removed, which reduces the roughness of the surface. Furthermore, a material connection is thus created between the partial bodies at the joining surface. A separate step of joining the partial bodies thus becomes unnecessary. A partial body produced in an additive production process can be joined in this way, for example, to at least one partial body produced in an injection molding process and/or to at least one other partial body produced in an additive production process.
It is conceivable that the partial bodies are first placed in the chamber and then the solvent atmosphere is introduced into the chamber. On the other hand, it is conceivable that the partial bodies are introduced into a chamber provided with a solvent atmosphere. The solvent atmosphere is, for example, an aerosol, in particular a mist, i.e., a mixture of an atomized solvent and air, for example. On the other hand, it is conceivable to use solvent vapor in pure form or mixed with air, for example, as a gas mixture.
To accelerate the reaction, the chamber can be heated to a temperature of 25 to 100° C., for example. The method does, however, preferably takes place at room temperature. The solvent atmosphere can be produced, for example, by spraying a solvent or by atomizing the solvent, for example by means of an ultrasonic atomizer. A targeted evaporation of the solvent is conceivable as well.
Because of the health hazard and potential explosion hazard, the chamber is preferably hermetically sealed during the presence of the solvent atmosphere. It is conceivable that the solvent atmosphere is evacuated before the chamber is opened at the end of the process.
It is advantageous if the at least two partial bodies are joined together on the at least one joining surface in a positive-fitting manner. This improves the subsequent cohesion of the at least two partial bodies. In addition, it is easier to produce a homogeneous composite body in this way. The positive fit can result, for example, from the fact that the joining surface between the partial bodies is formed by boundary surfaces of unit cells of a lattice structure of the partial bodies.
If the partial bodies each have a lattice structure, the partial bodies touch one another, for example, along lattice bars of the lattice structure. These lattice bars can, for example, form the edges of the unit cells of the lattice structure. The positive fit described here can relate to the parallel alignment of the lattice bars. A plurality of joining surfaces can consist of a plurality of lattice bars aligned in parallel and in pairs.
It is particularly advantageous if at least one of the partial bodies is produced with a powder-based 3D printing process. In contrast to other 3D printing methods, this method makes it possible to print the partial bodies without an additional support structure. A subsequent removal of a support structure is therefore not necessary.
In powder-based 3D printing processes, the bodies to be printed are built up layer by layer from a powder. This usually starts with the bottom layer with a binder being applied to a layer of powder, for example, which hardens and binds the powder in a targeted manner. The next layer of powder is then applied and treated with the binder as well. It is also conceivable to harden and bind the powder in a selective heating process.
In this context, the printed body is always in a loose powder environment that protects and supports the body. After this process, the body generally has a rough surface which, however, is smoothed in the solvent atmosphere within the context of the method. Naturally, both or all of the at least two partial bodies can be produced in the powder-based 3D printing process.
It is also advantageous if at least one of the two partial bodies is produced with a lattice structure. Due to the lattice structure, a large volume can be filled with little material. The elasticity of the partial body can also be precisely controlled by the lattice structure. This is particularly advantageous for padding. Ideally, the joining surface of the partial bodies is no longer recognizable in the composite body, at least on the basis of an inhomogeneous elasticity. Both or all of the at least two partial bodies can be produced with a lattice structure. In this case, the lattice structure of the partial bodies is preferably the same.
It is advantageous if the at least two partial bodies are placed in the solvent atmosphere in such a way that they touch at a plurality of joining surfaces, the plurality of joining surfaces corresponding to a plurality of boundary surfaces of the unit cells of the structure of the partial bodies. This ensures that the structures of the partial bodies complement each other to form a structure of the composite body that is as uniform as possible. This improves the homogeneity, particularly with regard to the elasticity of the body. The structure described can be any structure that is made up of a large number of identical unit cells, i.e., the smallest space-filling components. In particular, the structure is a lattice structure. The boundary surfaces separate the individual unit cells from one another. They do not necessarily have to be filled with material. The lattice bars joined to one another may form the edges of a boundary surface as well, for example.
Preferably, this aspect is already taken into account in the design or in the subdivision of the body into partial bodies before the production of the partial bodies. The lattice structure of the body is separated, for example, into the partial bodies along the boundary surfaces of the unit cells of the structure (so-called “cell-conforming cutting”).
It is also advantageous if the partial bodies are joined together in such a way that a uniform lattice structure of the composite body is formed. As already described, this can improve the homogeneity, in particular with regard to the elasticity of the body.
Especially when the body is padding or part of a padding element with which a subsequent user has direct contact, inhomogeneities in the elasticity can be uncomfortable for the user and thus disadvantageous for the economic success of the body. This is to be avoided.
It is advantageous if the at least two partial bodies are produced with at least one connecting element, in particular a connecting joint. In addition or as an alternative, it is advantageous if the at least two partial bodies are folded together via the connecting element so that the two partial bodies rest against one another with their corresponding joining surfaces. This ensures an error-free assembly of the partial bodies along the at least one joining surface. In particular, the freedom of movement of the partial bodies relative to one another can be restricted by one or more joints in such a way that the partial bodies can only be assembled in one way to form the body. It is conceivable to “collapse” the partial bodies to form the body. The connecting joint or the connecting joints can also be produced by the additive production process. If necessary, the joint or joints can be removed again after the partial bodies have been joined to form the body.
In the case of a particularly wide body that exceeds the width of the printing device, it is conceivable to subdivide the body into at least two partial bodies that can be printed one above the other and that are possibly joined to the described connecting joint or joints. In particular, two connecting joints can be provided.
Furthermore, it is advantageous if the at least two partial bodies are produced from a thermoplastic, in particular polyamide 12 (PA12) and/or an elastomer, in particular TPU. On the one hand, this makes it easier to produce the partial bodies. On the other hand, after the parts have been joined together, this results in an elastically deformable but dimensionally stable body, for example, which can be used in particular as padding.
Examples of elastomers are vulcanizates of natural or silicone rubber. The abbreviation TPU stands for thermoplastic polyurethane. Polyurethanes are plastics or synthetic resins that result from a polyaddition reaction of dialcohols or polyols with polyisocyanates. Padding or thermal insulation materials in particular can advantageously be produced from foamed TPU. The thermoplastic properties are particularly advantageous during the production of products from these materials.
There are particular advantages when the solvent atmosphere contains chloroform, tetrahydrofuran, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, hexafluoroisopropanol, pyridine and/or benzyl alcohol. These solvents are capable of dissolving TPU in particular and are therefore suitable for smoothing the surface of the partial bodies in an atmosphere and for establishing a positive connection between the partial bodies. It is conceivable to use a mixture of different solvents in the solvent atmosphere. As already described, an aerosol and/or a vapor can be produced from these solvents to create the solvent atmosphere.
The composite body is composed of at least two partial bodies with at least one of the partial bodies being produced in an additive production process. It is characterized in that it is produced according to a method as described above. As already described, the body has the advantage that the partial bodies are already joined together while the surface of the partial bodies is being smoothed and thus eliminating an additional work step of joining them together during the production of the body. In addition, the body may have a size that exceeds the printing range of a printing device for an additive production process. It is conceivable that the body is composed of a large number of partial bodies.
The body has a lattice structure, for example, with the lattice structure preferably being homogeneous across the entire extent of the body. Motifs of the lattice structure are repeated at regular intervals, for example. The body is made, for example, from an elastomer and in particular from TPU. The body is designed in particular as padding or part of a padding element with a homogeneous elasticity.
Further advantages of the invention are described in the following embodiments. In the drawings:
In the following description of the figures, the same reference signs are used for features that are identical and/or at least comparable in the various figures. The individual features, their design and/or mode of action are generally explained in detail when they are mentioned the first time. If individual features are not explained in detail again, their design and/or mode of action corresponds to the design or mode of action of the features already described that have the same effect or the same name.
The computing unit 2 can comprise at least one input interface 7 for detecting, inputting and/or determining the at least one external dimension AM and/or internal dimension IM. Using the input interface 7, geometrical data 8 of the body 4 to be produced and/or the production device 3 can be recorded, entered and/or determined automatically and/or with the help of a user. The overall model 5 can be created on the basis of this geometrical data 8. Additionally or alternatively, a digital image of the production device 3 and/or the internal dimension IM can be entered and/or stored in the computing unit 2. Additionally or alternatively, the computing unit 2, as shown in the embodiment, can have an output interface 9 for outputting production data 10 to the production device 3 and/or to a computer-readable storage medium 11. This production data 10 can be created with the aid of the computing unit 2.
A method, in particular a computer-implemented method, for dividing the virtual three-dimensional overall model 5 is illustrated in
For this purpose, according to
Subsequently, in a following step according to
An essential step of the method consists in the creation of a virtual separating surface 28 for the overall model, as shown in
The three-dimensional cell-conforming shape of the separating surface 28 is preferably created by an algorithm that is stored on the computing unit 2. The three-dimensional cell-conforming shape of the separating surface 28 is created by using the cell surface 26 and/or the edges 25 of the unit cells 24 adjacent to the respective cut surface 23. For this purpose, according to
As can be seen from
According to
The separating surface 28 shown in
Before, during or after the creation of the virtual three-dimensional separating surface 28, the overall model 5 of the body 4 shown in
The overall model 5 shown in
The lattice structure 35 of the overall model 5 shown in
In addition to the two partial models 13, two sub-partial models 16 are shown in
In addition, at least one locking element 17 is advantageously arranged on at least one of the partial models 13 and/or sub-partial models 16. In the embodiment shown, a part of the locking element 17 is arranged on each of the two partial models 13. The locking element 17 is designed here as a detent and receptacle for the detent. The locking element 17 can lock the two corresponding partial models 13 in the joining position in which the two joining surfaces 14 abut one another. A body 4 in the joining position is shown in
In the embodiment shown in
The production model 12 is designed similarly to the embodiment in
Following the production, which is shown in
In the joining position, the body 4 can be exposed to a solvent atmosphere that can be formed in the chamber 21. As a result, the surface of the body 4 can be smoothed and/or the parts 18 of the body 4 can be positively connected to one another in the region of their abutting joining surfaces 14. If the two parts 18 are positively connected to one another in the region of the joining surfaces 14, the connecting element 15 and/or the locking element 17 can then optionally be removed. As a result, protruding elements can be removed from the body 4. Additionally or alternatively, the connecting element 15 can be designed as a film hinge. Such a connecting element 15 can be formed in such a way that it does not protrude from the body 4.
The two-dimensional representation serves to illustrate the principle. As a rule, the body 4 will have a three-dimensional shape according to the above description. As shown in
The partial bodies 44 are delimited in such a way that only whole and/or closed cells 34 are present in the lattice structure 35. In other words, the partial bodies 44 are delimited by boundary surfaces 45 of the cells 34. Likewise, a respective joining surface 14 of the partial bodies 44, where the partial bodies 44 touch during the process (see also
In particular, the composite body 4 has a continuous and homogeneous lattice structure 35. Ideally, the corresponding joining surfaces 14 are no longer recognizable after the completion of the method. The solvent atmosphere 47 can be produced in the manners already described. For safety purposes, the chamber 46 is hermetically sealed, for example, during the presence of the solvent atmosphere 47. The partial bodies 44 can, for example, be placed in the chamber 46 on supports (not shown) or hung up on hooks (not shown).
The present invention is not limited to the embodiments that are illustrated and described. Modifications within the scope of the claims are just as possible as a combination of features even if these are shown and described in different embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 110 650.8 | Apr 2021 | DE | national |
