DE102016210990A1 - Thermoforming mold and method for modeling and manufacturing the same - Google Patents

Abstract

The thermoforming mold (2) according to the invention for thermoforming a film comprises a thermoforming surface whose geometry is transferred to the film during thermoforming, and at least one vacuum channel which connects the thermoforming surface to a contact side of the thermoforming mold which is different from the thermoforming surface. In this case, the deep-drawing surface has a preferred partial region (21, 22, 23, 24, 27) whose geometry transmission to the film is subject to specific precision requirements compared to other regions. Furthermore, a geometric configuration and / or arrangement and / or physical nature of the at least one vacuum channel is adapted to the geometry of the preferred subregion (21, 22, 23, 24, 27) in such a way that the film is pressed close to the preferred subregion (21, 22 , 23, 24, 27). The deep-drawing mold (2) according to the invention is produced by a generative layer-building method.

Description

The present invention relates to a thermoforming mold for thermoforming a film and to methods of modeling and manufacturing such thermoforming mold. The thermoforming mold comprises a thermoforming surface, the geometry of which is transferred to the film during thermoforming, and at least one vacuum channel which connects the thermoforming surface to a contact side of the thermoforming mold which is different from the thermoforming surface. The invention is also directed to a modeling unit for modeling the thermoforming mold, a device which is designed and / or controlled for producing the thermoforming mold, and to a corresponding control unit.

During deep drawing, undesirable trapping of air bubbles between the film to be formed and the thermoforming surface of the thermoforming mold can occur, resulting in incomplete transfer of the geometry of the thermoforming surface to the film. This problem can especially occur in vacuum-assisted deep drawing, where the bringing together of the film with the thermoforming surface is assisted by the application of a gas negative pressure on a contact side of the thermoforming mold which is different from the thermoforming surface.

To avoid this problem, denture models made of air-permeable plaster are used, for example, in dental technology in the manufacture of plastic splints, so that air can better escape between the plastic splint and the denture model during deep-drawing.

Another example is out DE 10 2006 037 997 A1 It is known where a luminous three-dimensional decorative component is produced by attaching a flat electroluminescent film to a surface of a three-dimensional workpiece. It is necessary to heat the film or the workpiece and an associated activation of a melt or adhesive layer to produce an intact material composite between the workpiece and the film. In a specific embodiment, the attachment of the film to the workpiece is assisted by a vacuum built up from a flat underside of the workpiece. For uniform suction of the film on the workpiece surface, it is proposed to provide in the workpiece a plurality of regularly spaced air passage channels, which connect the surface of the workpiece with its underside. The workpiece is produced for example by injection molding.

However, conventional thermoforming methods reach their limits when the thermoforming surface has relatively pronounced unevenness or irregularities and at the same time it is required that precisely these unevenness or irregularities are transferred with high accuracy to the film to be formed.

The object of the present invention is therefore to provide an improved thermoforming mold of the type mentioned above and improved methods for their modeling and production, which preferably allow by deep drawing a film arbitrarily pronounced bumps or irregularities of the thermoforming surface almost arbitrarily precise to the film transfer. Among other things, this object of the invention is directed to the application mentioned at the beginning of the vacuum-assisted deep drawing.

The object of the invention is achieved by a thermoforming mold according to claim 1, a modeling method according to claim 11, a manufacturing method according to claim 11, a computer program according to claim 12, a modeling unit according to claim 13, a control unit according to claim 14 and a manufacturing apparatus according to claim 15. Further developments The invention are set forth in the dependent claims. In this case, the modeling method, the manufacturing method, the computer program, as well as the modeling unit, the control unit or the manufacturing device can be developed by the below-mentioned or in the claims executed features of the thermoforming mold and vice versa. Features of various aspects, advantageous developments and embodiments of the invention can furthermore be combined with one another.

The thermoforming mold according to the invention for thermoforming a film comprises a thermoforming surface, the geometry of which is transferred to the film during thermoforming, and at least one vacuum channel which connects the thermoforming surface to a contact side of the thermoforming mold which is different from the thermoforming surface. According to the invention, the deep-drawing surface has a preferred partial region whose geometry transmission to the film is subject to specific precision requirements compared to other regions of the deep-drawing surface. Furthermore, in accordance with the invention, a geometric configuration and / or arrangement and / or physical condition of the at least one vacuum channel is adapted to the geometry of the preferred subregion in such a way that the film rests close to the preferred subregion during deep drawing. In addition, the thermoforming mold according to the invention is produced by a generative layer construction process.

By virtue of said vacuum channels, the air (or generally a fluid, which may be a gas or a liquid) may merge the film with the thermoforming surface of the thermoforming mold escape to the contact side of the thermoforming mold. This allows a dense, ie substantially bubble-free (free of gas or liquid bubbles), concerns the film on the thermoforming surface. This effect can be particularly effective, for example, close to a vacuum channel opening in the deep-drawing surface. The individual adaptation of the vacuum channels according to the invention to the preferred partial region in the individual case makes it possible, during thermoforming, to reliably achieve a tight abutment of the film on the preferred partial region, preferably the entire.

The perforation of the thermoforming mold according to the invention (the provision of the at least one vacuum channel) is thus generally not regular or uniform as in the prior art, but depending on the specific geometry of the preferred sub-range strongly from a regular configuration and / or a uniform distribution within the Deviate thermoforming mold. The geometry of the preferred subregion and the achievable demands on the precision of their transfer to the film to be formed may therefore be in principle arbitrary with the thermoforming mold according to the invention; In particular, the irregularity or the fineness of unevenness in the thermoforming surface are in principle no limits. This opens up a wide range of possible applications in new fields or with new precision unachievable with traditional deep drawing techniques. Examples of this are given below.

The term "vacuum channel" in the context of the invention generally means a three-dimensional portion of the thermoforming mold, which has an increased permeability to gases or liquids compared to a surrounding region of the thermoforming mold. (In the following, for the sake of brevity, only gas permeability will be mentioned.) The term "vacuum" generally includes a negative pressure. A vacuum channel may, for example, constitute a passage opening in a substantially gas-impermeable region of the thermoforming mold.

However, a vacuum channel may also comprise a porous or latticed portion of the thermoforming mold, which has an increased gas permeability compared to a surrounding gas-permeable or gas-impermeable region of the thermoforming mold. In particular, the term "at least one vacuum channel" also includes cases of location-dependent differentiation of the gas permeability within a thermoforming mold which is partially or completely porous or lattice-like and has at least a portion ("vacuum channel") with an increased gas permeability, the thermoforming surface with the contact side the thermoforming mold connects.

In a porous or lattice-like vacuum channel in a porous or lattice-like deep drawing mold, increased gas permeability may be due to a physical nature of the vacuum channel, such as pore size, pore density, pore shape, lattice shape, grid spacing, or the like.

The required variety of possible embodiments of the at least one vacuum channel is realized by the inventive use of a generative layer construction method for producing the deep-drawing mold. Generative layer construction processes are also known by the term "additive manufacturing" or "additive manufacturing". Typically, an object is produced layer by layer by applying a build-up material and selectively solidifying the applied layer at locations corresponding to the respective cross section of the object to be produced. The respective cross sections are determined on the basis of a computer-based model, for example a CAD data set, of the object to be produced. An example of such a method is "selective laser sintering or laser melting," in which the selective solidification of the building material is effected by scanning the respective layer with a laser beam.

An adjustment of the geometry of a thermoforming mold to be produced, in particular an individual adaptation according to the invention of the at least one vacuum channel to the preferred subregion of the thermoforming surface, can therefore be carried out by a corresponding adjustment of the computer-based model of the thermoforming mold. In view of a change or choice of the geometry of the thermoforming mold to be produced, the generative layer construction is therefore extremely flexible and time-efficient, because in principle it does not require any apparatus adaptations.

The thermoforming mold according to the invention unfolds its effect according to the invention not only during thermoforming while applying a negative pressure to the contact side of the thermoforming mold (vacuum-assisted thermoforming). Rather, the effect according to the invention can also be used in all other deep-drawing processes, provided that during deep-drawing, a fluid can escape from it at the contact side of the thermoforming mold. (In the following, the suction of the film onto the thermoforming surface by the vacuum channels will often be the sole reason for reasons of clarity.) This should by no means be understood as a restriction to vacuum-assisted thermoforming.)

The film in the context of the invention is suitable for deep drawing. It may, for example, constitute or comprise a thin foil or a thin plate. It may also be configured, for example, flat, ie, in their overall dimensions have a greater length and a greater width than thickness. The latter is not absolutely necessary, in particular, the film may already have a curved contour before deep drawing. From the material are suitable, for example, metal or plastic films, which may be designed in particular thin, or thin plastic plates.

Preferably, in the case of the deep-drawing mold according to the invention, the geometric configuration and / or the geometric arrangement of the at least one vacuum channel deviate from a substantially regular configuration and / or a substantially uniform arrangement in the deep-drawing mold. On the one hand, vacuum channels known from the prior art have a regular design, such as rectilinear passage openings of constant cross-section or naturally formed pores in the gypsum. On the other hand, they have a uniform distribution within the thermoforming mold, in particular an arrangement of the same rectilinear vacuum channels at equal distances from one another or a statistical distribution of similar pores in the gypsum.

By a deviation from such, generalized as uniform, distribution of the vacuum channels in the thermoforming mold, in particular with respect to the thermoforming surface, the suction of the vacuum channels can be selectively distributed unevenly along the thermoforming surface on the film to be formed. Thus, for example, unevennesses of the preferred partial area (such as depressions, projections, trenches, edges, undercuts, etc.) with a relatively small surface area in the entire thermoforming surface due to a locally increased vacuum channel density or size can cause a stronger suction of the film than in others, flatter or more smoothly formed areas of the thermoforming surface. By this measure, it can be achieved, for example, that during thermoforming, the film closely follows an arbitrarily complex geometry of these unevennesses and, therefore, they are precisely transferred to the film. A similar effect can be achieved by an irregular configuration of the at least one vacuum channel, such as the shape and / or the location of its mouth (opening) in the thermoforming surface follows a bump and is thus adapted to their individual geometry. An irregular configuration of a vacuum channel may alternatively or additionally also consist of a cross-section that varies along the vacuum channel (i.e., in a direction transverse to the deep-drawing surface). For example, a cross-sectional area of the vacuum channel may become larger toward the contact side to achieve equal suction at a smaller opening area at the opening of the vacuum channel in the thermoforming surface.

In an advantageous embodiment of the thermoforming mold according to the invention, the preferred subregion comprises a depression and / or an elevation, and the geometric configuration and / or the geometric arrangement and / or the physical nature of the at least one vacuum channel is such to the geometry of the depression and / or the elevation adjusted so that the film migrates deep into the deepening and / or into a corner formed by the increase. This adaptation can be achieved, for example, as described above. Due to the dense intrusion of the film into such a depression or corner, its geometry is transferred particularly precisely to the film.

Preferably, in the thermoforming mold according to the invention, the preferred subregion comprises a depression and / or an increase of less than about 1 mm, preferably about 0.5 mm, particularly preferably about 0.2 mm, with respect to an area adjacent to the depression and / or elevation the thermoforming surface. Even with such small-dimensioned unevenness of the thermoforming surface can be reliably ensured with the thermoforming mold according to the invention during thermoforming a film every detail required. Such requirements may occur, for example, in products in dental technology or electronics and electrical industry.

Further, in the thermoforming mold of the present invention, the preferable size range is preferably less than about 70%, preferably about 50%, more preferably about 30%, of a total area of the thermoforming surface. In specific embodiments of this embodiment, the area of the preferred portion may even be less than about 20% or about 10% of the total area of the thermoforming surface. This embodiment ensures a required level of detail, especially in the case of large-area foils or plates to be formed, where emphasis is placed on special areas which in turn must be very accurate within the large area. Such products include, for example, large metal or plastic panels of various equipment housings in the automotive and supply industries, in the electrical industry, household appliances or medical equipment. Other examples are large plastic or metal products such as furniture and accessories (stand, etc.), toys, bathroom and interior equipment (shelf, table or sink, etc.) and advertising displays.

In an advantageous embodiment of the thermoforming mold according to the invention, the at least one vacuum channel opens at least partially into the preferred subregion. As a result, the escape of a gas or a liquid between the film and the thermoforming mold is possible directly in the region of the preferred sub-range during deep drawing. An undesirable bubble entrapment in this area can thus be particularly effectively prevented.

In a preferred further development of this embodiment, an overall opening area of the at least one vacuum channel in the preferred partial area follows at least in sections a contour of the preferred partial area. In other words, one or more openings of the at least one vacuum channel in the preferred subregion extend at least in sections along a contour of the preferred subregion. For example, a contour of the preferable portion may constitute an outer or inner edge of the preferential portion (or a part thereof) in the deep-drawing surface. Alternatively, however, a contour of the preferred partial region may also be an abstract line which runs only roughly along a more complicated edge of the preferred partial region.

By the extension of vacuum channel openings along a portion of a contour of the preferred sub-area a tight contact of the film is secured to this section during deep drawing. As a result, the corresponding edge section of the preferred section is precisely imaged onto the film to be formed. In many cases, a tight contact of the film at certain edge portions of the preferred portion already without further measures to a dense concern of the film on the entire preference section. In individual cases, this depends on the specific shape and surface structure of the preferred subsection.

If, in this further development, a single vacuum channel opens in the preferred partial region, its opening surface in the preferred partial region runs at least partially along a contour of the preferred partial region. If, in contrast, several vacuum channels open in the preferred partial region, then, for example, some of their openings can be distributed at least in sections along a contour of the preferred partial region, in particular evenly. Alternatively or additionally, at least one of the openings may extend at least partially along a contour of the preferred subregion. Considering purely by way of example a circular preferred subregion, for example, a vacuum channel could open therein with an opening which has the shape of a (partial) annulus with only a slightly smaller radius than the radius of the preferred subregion. Alternatively or additionally, in this example a plurality of vacuum channel openings can be distributed within the preferred subregion along its circumference.

In an advantageous embodiment of the thermoforming mold according to the invention, the preferred subregion comprises a depression and / or an elevation and / or an edge, which may be arranged, for example, in the interior of the preferred subregion or else at its edge. According to this embodiment, the at least one vacuum channel comprises an opening in the preferential partial region, which extends at least in sections along a contour of the depression and / or along a contour of the elevation and / or along the edge. Alternatively or additionally, the at least one vacuum channel comprises a plurality of openings in the preferred subregion, which are distributed at least in sections along a contour of the depression and / or along a contour of the elevation and / or along the edge. This distribution of the vacuum channel openings is particularly preferably uniform. For reasons similar to the above-described embodiment, in the present embodiment, the extension of the vacuum channel opening (s) along said unevenness of the preferred portion ensures that such unevenness is accurately imaged on the film to be formed.

Preferably, in the case of the deep-drawing mold according to the invention, the at least one vacuum channel comprises a plurality of openings distributed in the preferred partial region. As a result, the suction effect is distributed to the film to be formed during deep drawing over the preferential part region, which in turn makes it possible to reliably achieve a tight contact of the film with the entire preferred partial region. In addition, a plurality of smaller openings in the preferred partial area can have an advantage over a few larger openings in that more of the surface structure of the preferred partial area can be retained, which can be favorable, in particular, in the case of fine or filigree unevenness of the preferred partial area. Also, the mechanical integrity or stability of the thermoforming mold may be a matter of consideration in a choice between a plurality of separate or few contiguous vacuum channel openings and / or vacuum channels. Several openings in the thermoforming surface may belong to a common vacuum channel and vice versa. Particularly preferred may be a substantially uniform distribution of the openings in the preferred sub-region, in order to achieve a uniform suction of the film over the preferential portion.

In a specific embodiment of the invention, the thermoforming mold comprises a dental model representing at least a portion of a human or animal jaw. The thermoforming mold may for example represent a single dental model or several dental models include. A respective dental model can represent from a single tooth or a single tooth gap to a whole jaw. By means of such a patient-specific dental model, the geometry of the corresponding jaw region during the deep-drawing process can be transferred to a film to be formed. In particular, a patient-specific plastic splint (for example tooth or jaw splint) and / or an active substance film for tooth bleaching can thus be produced.

Especially in dental technical applications, a detail in a selected part of the dental model (preferred sub-range of the deep-drawing surface according to the invention) can be subject to stricter precision requirements than in other areas of the dental model. For example, it may be necessary for a tooth bleaching foil to be particularly close to the patient's teeth in the area of interdental spaces and / or tooth pits and / or close to the gums, where tooth discoloration is often most pronounced. Similarly, a plastic dental splint may, for example, be required to follow the denture more closely near the necks of the teeth than in other dental regions.

• • Automobil- und Zulieferindustrie (insb. Gehäuse und Verkleidungen von Geräten, Armaturen, Innenauskleidung diverser Räume in Fahrzeugen)
• • Elektroindustrie (insb. Gehäuse, Verkleidungen, Bauteile, Halterungen)
• • Elektronikindustrie (insb. Gehäuse, Verkleidungen, Halterungen)
• • Spielwarenindustrie
• • Arbeits-, Wohn- und Sanitärraumeinrichtung (insb. Verkleidung von Einbaugeräten wie Klimaaggregat, Beleuchtungsbauteile wie Lampenschirme, aus Metall oder Plastik gefertigte Möbel und Zubehör wie Standfüsse, aus Metall oder Plastik gefertigte Badeinrichtung wie Waschbecken etc.)
• • Supermarktketten (insb. Werbedisplays, Verpackung, Inneneinrichtung, Lagerungs- und Transporttrays)
• • Besteckindustrie (insb. Plastikbesteck, Verpackung und Lagerung von Besteck)
• • Münz- und Medaillenetuis (insb. bei Individualisierungsbedarf, Kleinserie etc.)
• • Unterhaltungsindustrie, Multimedia, Video, CD, DVD (insb. Gehäuse von Produkten und Geräten)
• • Kosmetikindustrie (insb. Halter, Ständer und Boxen für Kosmetikprodukte und -Gebrauchsgegenstände wie Bürsten, Pinsel etc.)
• • Blister, Klappblister
• • darüber hinaus Tiefziehteile (als Einweg- oder Mehrwegartikel) für:
• – Lagerung
• – Transport
• – Handling
• – Weiterverarbeitung
• – Werkstückträger und Transporttrays
• – Verkaufsverpackungen
• – Präsenter und Displays
• – Innenverpackungen
• – Einsätze.

Further fields of use and examples of application for the thermoforming mold according to the invention are inter alia

• • Automotive and supplier industry (especially housings and panels of equipment, fittings, interior lining of various rooms in vehicles)
• • Electrical industry (especially housings, panels, components, brackets)
• • Electronics industry (especially housings, panels, brackets)
• • toy industry
• • working, living and sanitary facilities (especially cladding of built-in appliances such as air conditioning unit, lighting components such as lampshades, furniture made of metal or plastic and accessories such as feet, metal or plastic bathroom equipment such as sinks etc.)
• • Supermarket chains (especially advertising displays, packaging, interior design, storage and transport trays)
• • cutlery industry (esp. Plastic cutlery, packaging and storage of cutlery)
• • Coin and medal cases (especially for customization, small series, etc.)
• • entertainment industry, multimedia, video, CD, DVD (especially case of products and devices)
• • Cosmetics industry (in particular holders, stands and boxes for cosmetic products and consumer items such as brushes, brushes, etc.)
• • blisters, folding blister
• • In addition, deep drawn parts (as disposable or reusable articles) for:
• - Storage
• - Transportation
• - Handling
• - Further processing
• - Workpiece carriers and transport trays
• - Sales packaging
• - presenter and displays
• - Inner packaging
• - Calls.

A further aspect of the invention is a modeling method for modeling a thermoforming mold according to the invention, preferably based on a three-dimensional computer-based model (for example a CAD model) of a predetermined thermoforming mold. According to the modeling method according to the invention, a thermoforming surface is defined in a, in particular predetermined, thermoforming mold whose geometry is to be transferred to the film during thermoforming. Furthermore, according to the invention, a preferred subregion of the deep-drawing surface is selected, whose geometry transfer to the film is subject to specific precision requirements compared to other regions. The modeling method further comprises modeling at least one vacuum channel that connects the thermoforming surface to a contact side of the thermoforming mold other than the thermoforming surface. In the modeling step according to the invention, a geometrical configuration and / or arrangement and / or physical condition of the at least one vacuum channel is adapted to the geometry of the preferred subregion in such a way that the film rests tight against the preferred subregion during deep drawing.

Thus, in the modeling method according to the invention, on the one hand, a preferred partial area of the deep-drawing surface is defined individually for each thermoforming mold, depending on the specific requirements for the precision of its transfer to the film to be formed in the individual case. On the other hand, the perforation of the thermoforming mold with vacuum channels is individually modeled in each application, depending on the specific geometry of this preferred subregion. Overall, therefore, with the modeling method according to the invention of the deep-drawing mold, any precision requirement for its transfer to the film to be formed can be reliably guaranteed even with any uneven and / or irregularities of the deep-drawing surface.

A further aspect of the invention is a method for producing a thermoforming mold by means of a generative layer construction method. The production method according to the invention comprises a step of receiving a modified computer-based model of a modeling method according to the invention predetermined deep-drawing mold and a step of producing the thermoforming mold by the generative layer construction method based on the modified computer-based model. The manufacturing process comprises the steps of applying a layer of building material within a construction field and selectively solidifying the applied layer at locations corresponding to a respective cross section of the deep drawing mold to be produced. The steps of application and selective solidification are repeated until the thermoforming mold is completed.

Furthermore, a computer program according to the invention is provided which can be loaded into a programmable modeling unit for modeling a thermoforming mold and / or into a programmable control unit for a device for the generative production of a three-dimensional object. The computer program according to the invention comprises a program code for carrying out all steps of a modeling method according to the invention and / or a production method according to the invention when the computer program is executed in the modeling unit and / or control unit.

Another aspect of the invention is a modeling unit for modeling a thermoforming mold according to the invention. The modeling unit according to the invention is designed to carry out a modeling method according to the invention. For example, for this purpose, a computer program according to the invention can be loaded into the modeling unit.

Furthermore, a control unit according to the invention for a device for generatively producing a three-dimensional object by layering and selectively solidifying a building material is provided. In this case, the device preferably comprises a coater movable over a building field for applying a layer of the building material within the construction field and a solidifying device for selectively solidifying the applied layer at locations which correspond to a respective cross section of the object to be produced. The control unit according to the invention is designed to control the device so that it carries out a production method according to the invention. For example, for this purpose, a computer program according to the invention can be loaded into the control unit.

Another aspect of the invention is an apparatus for generatively producing a three-dimensional object by layering and selectively consolidating a build material, preferably comprising a field movable coater for applying a layer of build material within the build field and solidification means for selectively strengthening the applied layer Positions that correspond to a respective cross-section of the object. The device according to the invention is designed and / or controlled to carry out a production method according to the invention. In particular, a control unit according to the invention can serve for the corresponding control.

The above-mentioned and other features and effects of the invention are described below with reference to embodiments with reference to the drawings. The representation of the manufacturing apparatus and the thermoforming mold in the drawings is purely schematic and is therefore not to be understood as true to scale. Identical or mutually corresponding elements of different examples are identified by the same reference numerals.

1 is a schematic sectional view of a device according to the invention for the generative production of a three-dimensional object,

2 is a schematic side view of a thermoforming mold according to the invention in the form of a dental model and

3 is a schematic plan view of another deep-drawing mold according to the invention in the form of a dental model.

Regarding 1 becomes an example of a device 1 for generatively producing a three-dimensional object, which is designed and / or controlled for carrying out a method according to the invention for producing a deep-drawing mold. In the 1 schematically illustrated layering device 1 is a laser sintering or laser melting device. To build a three-dimensional object 2 , in particular a thermoforming mold according to the invention, it contains a process chamber 3 with a chamber wall 4 ,

In the process chamber 3 is an open-topped container 5 with a container wall 6 arranged. In the container 5 is a movable in a vertical direction V carrier 7 arranged on which a base plate 8th attached to the container 5 closes down and thus forms its bottom. The base plate 8th Can one separate from the carrier 7 be formed plate, the carrier 7 is attached, or it can be integral with the carrier 7 be formed. Depending on the building material used (especially powder) and process may be on the base plate 8th another platform 9 be attached as a construction document on which the object 2 is built. The object 2 but also on the base plate 8th even be built, which then serves as a construction document. In 1 is that in the container 5 on the platform 9 object to be formed 2 below one through the top of the container wall 6 defined construction field 10 presented in an intermediate state with several already solidified layers, surrounded by the unresolved construction material 11 ,

The laser sintering device 1 also contains a reservoir 12 for a solidified by electromagnetic radiation powdery building material 13 and a coater drivable in a horizontal direction H. 14 for applying layer by layer the building material 13 on the construction substrate or a last applied layer within the construction field 10 , Optional is in the process chamber 3 a radiant heater 15 for heating the applied building material 13 arranged. As radiant heating 15 For example, can serve an infrared radiator.

The laser sintering device 1 also includes an exposure device 30 with a laser 31 , a laser beam 32 generated. The laser beam 32 is via a deflection device 33 deflected and by a focusing device 34 via a coupling window 35 Located at a top of the process chamber 3 in the chamber wall 4 is attached to the construction substrate or a last applied layer of the building material 13 focused.

Next contains the laser sintering device 1 a control unit 39 via which the individual components of the device are controlled in a coordinated manner for carrying out the construction process, in particular a method according to the invention (in 1 indicated by arrows). At the control unit 39 it is preferably a control unit according to the invention. Alternatively or additionally, a control unit may also be partially or completely outside the device 1 to be appropriate. The control unit may include a CPU whose operation is controlled by a computer program (software). The computer program can be stored separately from the device on a storage medium, from which it can be inserted into the device, in particular into the control unit 39 , can be loaded. Preferably, it is the computer program according to the invention with a program code for carrying out a method according to the invention in the laser sintering device 1 ,

For modeling a thermoforming mold according to the invention, the device comprises 1 further a modeling unit 40 , which is designed for carrying out a modeling method according to the invention. In the example shown, the modeling unit is 40 a separate electronic unit in the device 1 and is adapted to the control unit 39 to obtain a three-dimensional computer-based model, in particular a CAD model, a predetermined thermoforming mold and after performing a modeling method according to the invention a modified computer-based (CAD) model of the deep drawing mold according to the invention to be produced to the control unit 39 pass. A modeling unit 40 with this functionality may alternatively be a part of the control unit 39 be, or partially or completely outside the device 1 to be appropriate.

The modeling method according to the invention, that of the modeling unit 40 includes defining a thermoforming surface in the given thermoforming mold (the definition of the thermoforming surface may already be included in the given CAD data), and the steps of selecting a preferred subregion and modeling the at least one vacuum channel according to the invention. Preferably, in the modeling unit 40 For the automated implementation of the modeling method, a computer program according to the invention is loaded. Optionally, the modeling unit may be configured to perform the modeling process interactively with a user so that the user can at least partially co-determine the execution of the above steps of the modeling process as a designer. By involving a skilled thermoforming mold designer in selecting the preferred subregion and / or modeling the vacuum channels, it is possible, in particular, to use the modeling unit 40 on novel, possibly not included in the computer program areas of thermoforming technology with their specific requirements for the vacuum channel design.

In operation, there is the construction pad, which in this example is a surface of the platform 9 is, at the beginning of the manufacturing process at the height of the construction field 10 and is lowered for applying a powder layer in each case by a height corresponding to the desired layer thickness. By method of the coater 14 within the construction field 10 each becomes a layer of the powdered building material 13 applied to the construction substrate or an already existing upper powder layer. The application takes place at least over the entire respective cross-section of the object to be produced 2 , Optionally, the powdered building material 13 by means of radiant heating 15 heated to a working temperature. Subsequently, the cross section of the object to be produced 2 from the laser beam 32 scanned so that the powdered building material 13 is solidified at the points corresponding to the cross section of the object 2 correspond. These steps are repeated until the object 2 , for example, an in 2 and 3 shown thermoforming mold, is completed.

2 schematically shows a side view of a thermoforming mold according to the invention, in this example in the form of a patient-specific dental model 2 , The dental model 2 represents a section of a four tooth human mandible 16 . 17 . 18 and 19 It can be used for example for the production of a plastic dental splint or a drug film for tooth bleaching by vacuum-assisted deep drawing. In these applications, it is particularly important that the film to be formed in deep drawing, ie bubble-free, in between the teeth 16 - 19 and the adjacent gums 20 formed fine trenches 21 . 22 . 23 and 24 hineinmigriert. In other words, it is necessary that the finished plastic splint or drug sheet the trenches 21 - 24 Despite its small depth compared to other Gebißunebenheiten particularly closely replicates, because problems to be treated such as tartar, exposed necks or tooth discoloration are often most pronounced there.

In this example, for example, the entire outer contour of the teeth 16 - 19 and possibly a part of the gum 20 define a thermoforming surface according to the invention, the geometry of which is to be transferred to the film to be formed. The trenches 21 - 24 form because of the higher precision requirement at the geometry transfer a preferred sub-range within the thermoforming surface according to the invention.

A close concern of the film at the ditch 22 a smaller tooth 17 is ensured in this example that the geometric design of a vacuum channel, in particular its opening 25 in the ditch 22 , to the geometry of the trench 22 is adjusted. In 2 this is due to an extension of the elongated opening 25 along the dike 22 achieved. For a larger tooth 18 are some vacuum channels with circular openings 26 along the correspondingly longer trench 23 equally distributed. Preferably, the elongated vacuum channel opening 25 narrow compared to an entire side surface of the tooth 17 and the circular openings 26 small compared to an entire side surface of the tooth 18 designed to allow the vacuum channel openings 25 . 26 the smallest possible area proportion of the respective trench 22 . 23 taking. The openings 26 do not have to be circular, but can also have any other geometric shape.

3 shows a schematic plan view of another deep-drawing mold according to the invention in the form of a patient-specific dental model 2 , In contrast to the dental model 2 represents the dental model 2 in 3 a human jaw section with a single molar 19 and surrounding gums 20 represents.

Again, for example, an entire outer surface of the molar tooth 19 and possibly part of the surrounding gums 20 define a thermoforming surface according to the invention. In this example, it may be necessary for a very uneven occlusal surface 27 of the molar tooth 19 is transferred particularly precisely to a plastic film or rail by vacuum-assisted deep drawing. Therefore, here can the occlusal surface 27 are selected as a preferred partial area of the deep-drawing surface according to the invention.

A close concern of a film to be formed on the occlusal surface 27 is secured in this example by having an elongated vacuum channel opening 28 along an in 3 left edge of occlusal surface 27 extends and two circular vacuum channel openings 29 at both ends of an in 3 right edge of the occlusal surface 27 are arranged. The oblong opening 28 for example, to its two ends 28a and 28b towards, broadening to increase a suction effect on the film to be formed at these locations, or vice versa. Incidentally, the same applies in relation to 2 Said accordingly.

Although the present invention has been described with reference to a laser sintering or laser melting apparatus, it is not limited to laser sintering or laser melting. It can be applied to any methods of generatively producing a three-dimensional object by layering and selectively solidifying a building material (preferably in powder form), regardless of the manner in which the building material is solidified. The selective solidification of the applied build-up material may be accomplished by a power supply of any suitable type. Alternatively or additionally, for example, it can also be carried out by 3D printing, for example by applying an adhesive.

In selective solidification by energy supply, energy can be supplied to the building material in general, for example, by electromagnetic radiation or particle radiation. In this case, the radiation acts on the building material in the respective region of a layer to be solidified in such a way that it changes its state of aggregation, undergoes a phase transition or another structural change and is present in a solidified form after a subsequent cooling process. Preferably, the building material is a powder, wherein the radiation may be in particular a laser radiation. In this case, the radiation acts on a region of the respective layer to be solidified such that powder grains of the building material in this region are partially or completely melted by the energy introduced by the radiation be and connected together after cooling down as a solid.

An exposure device for selective solidification by energy supply, for example, one or more gas or solid state lasers or any other type of laser such. As laser diodes, in particular VCSEL (Vertical Cavity Surface Emitting Laser) or VECSEL (Vertical External Cavity Surface Emitting Laser), or include a row of these lasers. In general, any device can be used for the exposure, with the energy can be selectively applied as a wave or particle radiation on a layer of the building material. Instead of a laser, for example, another light source, an electron beam or any other energy or radiation source can be used, which is suitable to solidify the building material. Instead of deflecting a beam, it is also possible to use exposure with a movable line imagesetter. Also, selective mask sintering using an extended light source and a mask, or high-speed sintering (HSS), which selectively applies to the build material a material that increases the radiation absorption at the respective sites (absorption sintering) ) or decreased (inhibition sintering), and then exposed unselectively over a large area or with a movable line imagesetter, the invention can be applied.

In the present invention, basically all types of building material can be used, which are suitable for the generative production, in particular plastics, metals, ceramics, preferably in powder form, sand, filled or mixed powders.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely 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.

Cited patent literature

• DE 102006037997 A1 [0004]

Claims (15)

Thermoforming mold ( 2 ) for thermoforming a film, wherein the thermoforming mold ( 2 ) comprises: a deep-drawing surface, the geometry of which is transferred to the film during deep-drawing, and at least one vacuum channel which connects the deep-drawing surface to a contact side of the deep-drawing mold which is different from the deep-drawing surface, the deep-drawing surface having a preferential subregion ( 21 . 22 . 23 . 24 . 27 ), whose geometrical transmission to the film is subject to specific precision requirements compared to other regions, and a geometrical configuration and / or arrangement and / or physical condition of the at least one vacuum channel in such a way to the geometry of the preferred subregion ( 21 . 22 . 23 . 24 . 27 ) is adapted, that the film during deep drawing close to the preferred portion ( 21 . 22 . 23 . 24 . 27 ), and wherein the thermoforming mold ( 2 ) is produced by a generative layer construction method. Thermoforming mold ( 2 ) according to claim 1, wherein the geometric configuration and / or arrangement of the at least one vacuum channel of a substantially regular configuration and / or of a substantially uniform arrangement in the thermoforming mold ( 2 ) deviates. Thermoforming mold ( 2 ) according to claim 1 or 2, wherein the preferential portion ( 21 . 22 . 23 . 24 . 27 ) a recess ( 21 . 22 . 23 . 24 ) and / or an increase and the geometric configuration and / or arrangement and / or physical condition of the at least one vacuum channel in such a way to the geometry of the recess ( 21 . 22 . 23 . 24 ) and / or elevation is adapted, that the film during deep drawing tight in the depression ( 21 . 22 . 23 . 24 ) and / or into a corner formed by the elevation. Thermoforming mold ( 2 ) according to any one of the preceding claims, wherein the preferential portion ( 21 . 22 . 23 . 24 . 27 ) a recess ( 21 . 22 . 23 . 24 ) and / or an increase of less than about 1 mm, preferably about 0.5 mm, more preferably about 0.2 mm, with respect to one of the depression ( 21 . 22 . 23 . 24 ) and / or elevation of adjacent area of the thermoforming surface. Thermoforming mold ( 2 ) according to any one of the preceding claims, wherein the preferential portion ( 21 . 22 . 23 . 24 . 27 ) occupies less than about 70%, preferably about 50%, more preferably about 30%, of a total area of the thermoforming surface. Thermoforming mold ( 2 ) according to one of the preceding claims, wherein the at least one vacuum channel at least partially into the preferential portion ( 21 . 22 . 23 . 24 . 27 ), its total opening area ( 25 . 26 . 28 . 29 ) in the preferred subarea ( 21 . 22 . 23 . 24 . 27 ) preferably at least in sections a contour of the preferential subregion ( 21 . 22 . 23 . 24 . 27 ) follows. Thermoforming mold ( 2 ) according to any one of the preceding claims, wherein the preferential portion ( 21 . 22 . 23 . 24 . 27 ) a recess ( 21 . 22 . 23 . 24 ) and / or an elevation and / or an edge, and the at least one vacuum channel a) has an opening ( 25 . 28 ) in the preferred subarea ( 22 . 27 ), which at least partially along a contour of the recess ( 22 ) and / or along a contour of the elevation and / or along the edge, and / or b) a plurality of openings ( 26 . 29 ) in the preferred subarea ( 23 . 27 ) which at least partially along a contour of the recess ( 23 ) and / or along a contour of the elevation and / or along the edge, in each case preferably uniformly. Thermoforming mold ( 2 ) according to one of the preceding claims, wherein the at least one vacuum channel has a plurality in the preferential partial region ( 23 . 27 ), preferably substantially uniformly distributed openings ( 26 . 29 ). Thermoforming mold ( 2 ) according to one of the preceding claims, which comprises a dental model which reproduces at least a region of a human or animal jaw, in particular a dental model for producing a plastic splint and / or a tooth whitening active substance film. Modeling method for modeling a thermoforming mold ( 2 ) according to one of the preceding claims, preferably on the basis of a three-dimensional computer-based model of a predetermined deep-drawing mold, comprising the following steps: defining in a, in particular predetermined, deep-drawing form a thermoforming surface whose geometry is to be transferred to the film during thermoforming, selecting a preferred subregion ( 21 . 22 . 23 . 24 . 27 ) the thermoforming surface whose geometry transfer to the film is subject to specific precision requirements compared to other areas, modeling at least one vacuum channel connecting the thermoforming surface to a contact side of the thermoforming mold other than the thermoforming surface, wherein a geometric configuration and / or arrangement and / or physical nature of the at least one vacuum channel in such a way to the geometry of the preferential subregion ( 21 . 22 . 23 . 24 . 27 ), that during deep drawing the film is pressed close to the preferred portion ( 21 . 22 . 23 . 24 . 27 ) is present. Method for producing a thermoforming mold ( 2 by means of a generative layer construction method, comprising the steps of: receiving a computer-based model of a predetermined thermoforming mold modified using the modeling method according to claim 10, producing the thermoforming mold ( 2 ) by the generative layer building method based on the modified computer-based model, comprising the steps of: applying a layer of building material ( 13 ) within a construction field ( 10 ), selectively solidifying the applied layer at locations corresponding to a respective cross-section of the thermoforming mold ( 2 ) and repeating the steps of application and selective solidification until the thermoforming mold ( 2 ) is completed. Computer program that is stored in a programmable modeling unit ( 40 ) for modeling a thermoforming mold ( 2 ) and / or in a programmable control unit ( 39 ) for a device ( 1 ) for generatively producing a three-dimensional object ( 2 ) is loadable with a program code to perform all the steps of a modeling method according to claim 10 and / or a method according to claim 11, when the computer program in the modeling unit ( 40 ) and / or control unit ( 39 ) is performed. Modeling unit ( 40 ) for modeling a thermoforming mold ( 2 ) according to one of claims 1 to 9, designed for carrying out a modeling method according to claim 10. Control unit ( 39 ) for a device ( 1 ) for generatively producing a three-dimensional object ( 2 ) by layer-wise application and selective solidification of a building material ( 13 ), the device ( 1 ) one over a construction field ( 10 ) movable coater ( 14 ) for applying a layer of the building material ( 13 ) within the construction field ( 10 ) and a solidification device ( 30 ) for selectively solidifying the applied layer at locations corresponding to a respective cross-section of the object to be produced ( 2 ), and wherein the control unit ( 39 ), the device ( 1 ) so as to carry out the method according to claim 11. Contraption ( 1 ) for generatively producing a three-dimensional object ( 2 ) by layer-wise application and selective solidification of a building material ( 13 ), comprising: one about a construction field ( 10 ) movable coater ( 14 ) for applying a layer of the building material ( 13 ) within the construction field ( 10 ) and a solidification device ( 30 ) for selectively solidifying the applied layer at locations corresponding to a respective cross section of the object ( 2 ), the device ( 1 ) is designed and / or controlled to carry out the method according to claim 11.

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