Fiber molding manufacturing method and device

Abstract

The present invention relates to a method for producing a fibrous molded body (1), comprising the steps of: placing a suction mold (2) with porous walls (4) having a contour corresponding to the contour of the fibrous molded body (1) to be produced in a chamber (5); introducing a fibrous material-air mixture (6) into the chamber (5), where the fibrous material is dispersed in the air in the form of solid particles; sucking the fibrous material-air mixture (6) through the porous walls (4) of the suction mold (2) to compress the fibrous material and form a fibrous molded body (1) on the porous walls (4); and removing the fibrous material (1) from the suction mold (2) and the chamber (5). The present invention aims to provide a technically simple method and a technically simple apparatus that enable the rapid and energy-efficient production of biodegradable fibrous molded bodies, particularly with a low reject rate. To this end, the fibrous material, which mainly consists of cellulose fibers, is moistened and / or water is mixed into the fibrous material-air mixture in the form of droplets or steam.

Description

[Technical Field]

[0001] The present invention relates to a method and an apparatus for producing a fibrous molded article. [Background technology]

[0002] Fiber moldings are used in a variety of applications, particularly as packaging for transport and for protecting delicate cargo, for example, as replacements for plastic trays, as molded inserts in packaging, and as packaging for food.

[0003] It is known to produce fibrous bodies by the pulp molding process. In this process, a suction mold with porous walls is immersed in pulp, also known as a fiber slurry. The pulp usually contains at least water and fibers, which are sucked into the suction mold. The fibers are usually cellulose (Zellstoff). Suction is achieved through pores or openings in the porous walls of the suction mold that are smaller than the fibers. Thus, only the water in the pulp is sucked through the walls of the suction mold, while the fibers are deposited on the walls of the suction mold. The fiber content increases and compacts on the walls of the suction mold, resulting in the formation of a fibrous body there. After the fibrous body is demolded, subsequent drying further increases the dry matter content, thereby solidifying the fibrous body.

[0004] The pulp molding process can produce fiber moldings with complex contours in a suction mold. However, the fiber moldings deposited on the walls of the suction mold have a very high moisture content, so it takes a lot of time and energy to dry the wet fiber moldings. To make the formed fiber moldings usable, the water must be substantially completely evaporated. The pulp molding process consumes a considerable amount of water and energy.

[0005] Alternatives to the pulp molding process are known in the prior art. For example, Swedish Patent No. 541995 discloses a method for producing non-flat fibrous moldings, also known as cellulose products. This method involves dry-molding cellulose fibers into a flat cellulose web in a dry-molding unit. To dry-molde the cellulose web, the dry-molding unit includes a separation unit for separating the cellulose fibers, a molding sieve for forming a web from the cellulose fibers, and a compression unit for compressing the cellulose fibers. Water and one or more additives are added to the cellulose fibers and / or the cellulose blank. Molding of the cellulose product is carried out by heating the cellulose web to a molding temperature in the range of 140°C to 200°C and pressing the cellulose blank at a molding pressure of at least 4 MPa. In this case, the additive or additives are dispersed in solid form onto the cellulose fibers and / or the cellulose web. That is, in this method, the production of non-flat fibrous moldings is achieved via a circuitous route via a flat cellulose web.

[0006] EP 3889347 A1 also discloses a method for producing fibrous moldings, also referred to as molded articles. This method involves mixing fibers with a composite material to produce a mixture, which contains cellulose fibers and 30% to 50% starch at least partially fused to the cellulose fibers. The mixture is then moistened at least once and molded into a molded article by applying pressure and heat to the moist mixture. In particular, the moist mixture is deposited on a mesh conveyor belt, where it thickens. The conveyor belt transports the fibrous web to a molding device, where it is pressed. Thus, in this method too, the production of fibrous moldings takes a circuitous route via a flat fibrous web.

[0007] The production of a fiber web, which is then placed in the mold of the fiber molding to be produced, is time-consuming and energy-intensive, and furthermore, the pressing involves a large deformation of the fiber web, which can thin and / or tear during pressing into the defined shape.

[0008] US Pat. No. 5,376,327 and DE Pat. No. 10,201,520,0275 describe methods for producing fiber moldings using carbon fibers and plastic fibers. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Swedish Patent Invention No. 541995 [Patent Document 2] European Patent Application Publication No. 3889347 [Patent Document 3] US Patent Application Publication No. 5,376,327 [Patent Document 4] German Patent Application Publication No. 102015200275 Summary of the Invention [Problem to be solved by the invention]

[0010] The invention is based on the object of providing a technically simple method and a technically simple device which allows for the rapid and energy-efficient production of biodegradable fiber moldings, in particular with a low reject rate. [Means for solving the problem]

[0011] According to the invention, this problem is solved by a method having the features of claim 1 and by a device having the features of claim 10. Advantageous embodiments emerge from the dependent claims.

[0012] The method for producing a fiber molded article described herein comprises: The following steps: - placing in the chamber a suction mold with porous walls having a contour corresponding to the contour of the fiber molding to be produced; - introducing a fiber material-air mixture into the chamber, the fiber material being dispersed in the air in the form of solid particles; - sucking the fibrous material-air mixture through the porous wall of the suction mold and compressing the fibrous material to form a fibrous molding on the porous wall; - removing the fiber molding from the suction mold and the chamber; Including, The textile material consists mainly of cellulose fibers, the textile material is moistened and / or water is mixed into the textile-air mixture in the form of droplets or water vapor.

[0013] The invention is therefore based on the idea that the starting material (i.e. in particular the fiber material) for forming the fiber molding is deposited directly from the air onto a suction-type porous wall and compressed there, so that the fiber molding has the geometry (contour) to be created or at least substantially has the geometry (contour) to be created immediately after the deposition and compression of the starting material.

[0014] The fiber moldings are formed from biodegradable, preferably compostable, starting materials. In this case, the fiber materials are primarily formed from cellulose, other fiber materials, and / or refined fibers, each of which is biodegradable and preferably compostable, depending on the desired appearance characteristics of the fiber molding. This makes the fiber molding itself biodegradable and preferably compostable. As is known from the traditional production of fiber moldings by pulp molding, the fibers can be primarily cellulose fibers. However, other fibers, such as hemp fibers, can also be used. This allows for the production of fiber moldings with high strength and excellent mechanical properties. Depending on the application, fibers made from different starting materials can also be mixed.

[0015] To ensure that the fiber material solidifies when compressed and obtains the molding to be formed, the fiber material can be introduced into the fiber-air mixture in a slightly moist state. In this case, the moisture of the fiber material can cause problems when the fibers are swirled in the air. For this reason, water can be mixed into the swirled fiber-air mixture in the form of droplets (water droplets) or steam to achieve the optimum moisture content for the fibers to solidify when compressed. It is also possible to swirl completely dry fibers with air and to supply the entire amount of water required for solidification to the swirling fiber-air mixture.

[0016] In some embodiments, a first fibrous material-air mixture can be introduced into the chamber and aspirated, thereby forming a first layer of fibrous material on the porous walls of the suction mold, followed by aspirating at least one other fibrous material-air mixture into the chamber and aspirating at least one other layer of fibrous material on the porous walls of the suction mold. The multiple layers of fibrous material can be compressed to form a fibrous molding on the porous walls, and the fibrous molding can be removed from the suction mold. In other words, a first mixture can be introduced into the chamber to form a first layer on the porous walls, followed by a second mixture can be introduced to form a second layer on the first layer. This process can be repeated for third and fourth layers, etc., if necessary. In this case, the fibrous material-air mixtures for forming the various layers can be different. For example, the first fibrous material-air mixture can contain a different pigment than the second fibrous material-air mixture. In this case, the outer layer of the resulting molding will be a different color from the inner layer. Different additives can also be added to the layers. For example, if the fibrous molding is used for food packaging, the inner layer can be configured to be safe for direct contact with the food. A second layer can be deposited on top of this inner layer, which gives the fiber molding a specific density or strength but is not suitable for direct food contact. Multilayer moldings can also be created, with each layer having its own unique function, such as high density to prevent oxygen penetration, high moisture resistance, or high light resistance. By varying the composition of the fiber-air mixture, different properties can be achieved for the various layers to create layers with specific desired properties.

[0017] The suction mold can be, for example, a hollow body having a porous wall and suction openings for connecting a suction device, which are fluidly connected to the pores of the wall. Alternatively, the suction mold can be designed as an object formed from a porous structure having suction openings for connecting a suction device. In this case, the surface of the object or at least one surface portion forms the porous wall of the suction mold. The contour of the porous wall corresponds to the contour of the fiber molding to be produced. In other words, the surface geometry of the porous wall or a portion of the porous wall and the surface geometry of the fiber molding to be produced are complementary or substantially complementary. A suction device connectable to the suction mold can selectively generate negative or positive pressure in the suction mold, and air can be sucked or blown through the pores of the porous wall of the suction mold. The pores of the porous wall are preferably designed so that the fiber material accumulates on the wall when the fiber material-air mixture is sucked.

[0018] The porous wall of the suction mold can be formed, for example, by a wire mesh sieve. However, it can also be manufactured as a solid wall with air passages, for example by additive manufacturing (3D printing). In the second case, the suction mold is more stable.

[0019] The chamber is a predetermined space in which the fiber molding is formed on the porous wall of the suction mold. This space can have a peripheral wall with one or more openings through which the starting material for forming the fiber molding and / or the suction mold can be introduced into the space. The opening in the peripheral wall can be at least partially closed, for example, by a door, flap, or slider. The peripheral wall and the at least partially closable openings effectively prevent the fiber material-air mixture from escaping into the air outside the chamber.

[0020] The placement of the suction molds into the chamber can be performed manually or automatically. Automatic placement allows for automation of the method described herein. Automatic placement can be performed, for example, by a suction mold carrier moved by an electrically or pneumatically driven actuator. In this case, the drive of the actuator can be functionally connected to a control unit. The suction mold carrier can be designed, for example, as a conveyor belt on which the suction molds are placed and which moves the suction molds from the loading position into the chamber. Alternatively, the suction mold carrier can be, for example, a robot arm.

[0021] In the method described herein, multiple suction molds with the same or different porous wall designs can be placed in the chamber at the same time, thereby simultaneously forming multiple fiber moldings with the same or different contour designs. For small fiber moldings, each fiber molding can correspond to one of multiple sections of the porous wall of the suction mold. Simultaneous production of multiple fiber moldings allows for particularly rapid and energy-efficient production of multiple fiber moldings.

[0022] Before, during, or after the suction mold is placed in the chamber, a fiber material-air mixture is introduced into the chamber. For this purpose, the fiber material-air mixture can be premixed outside the chamber, so that the fiber material is already dispersed in the air in the form of solid particles when introduced. In this case, the fiber material-air mixture can be blown into the chamber, for example. Alternatively, the fiber material can be introduced into the chamber separately from the air. For example, during the molding process, the fiber material can be continuously dispersed into a chamber already filled with air, or injected in bulk into a chamber already filled with air.

[0023] Therefore, the method described herein allows the desired fiber molding to be formed directly in a single molding step without the need to previously form an intermediate product for further processing. This saves considerable time. In addition, the formed fiber molding contains almost no water and therefore does not need to be dried. Water, if any, is added only to the extent necessary to optimally solidify the components of the fiber molding wall.

[0024] Regardless of how the fibrous material is introduced, it may be advantageous to actively and precisely move the air, fibrous material, and / or fibrous material-air mixture in the chamber to achieve a uniform mixing of the air and the starting material for forming the fibrous molding. Active and precise movement of the air, fibrous material, and / or fibrous material-air mixture can be achieved by a device for mixing the fibrous material with the air, such as a propeller. The propeller creates a vortex in the air and / or fibrous material-air mixture, thereby uniformly dispersing the fibrous material in the air. The propeller can generate an upward flow, in particular, which can create a fluidized bed in the chamber. A fluidized bed is a bulk of solid particles that are lifted and fluidized by an upward flow of a fluid. The term "fluidized" means that the (former) bulk has fluid-like properties. Instead of or in addition to a propeller, the device for mixing the fibrous material with the air can have, for example, a vibrating membrane, which vibrates and lifts the air, fibrous material-air mixture, and / or particles of starting material deposited on the membrane.

[0025] To form the fiber molding, air is sucked through the porous walls of the suction mold, where the fiber material is deposited on the porous walls. After a certain suction time, the fiber material-air mixture is sucked out, compressing the fiber material on the porous walls and forming a fiber molding with the desired shape and thickness.

[0026] Once a predetermined suction time and / or the desired wall thickness of the fiber molding has been reached, the fiber molding is removed from the suction mold and chamber and either further processed or placed in intermediate storage.

[0027] In practice, the porous wall of the suction mold can have a three-dimensional contour comprising multiple wall sections. The wall sections of the suction mold define the various sections of the molded body to be produced. Individual wall sections can be designed to be flat, convex, and / or concave. This allows the porous wall to be formed with a three-dimensional fiber molding having multiple surface portions, such as a cup-shaped fiber molding having a flat bottom and a cylindrical cup wall. As mentioned above, multiple fiber moldings can also be formed on multiple surface portions of the suction mold.

[0028] Furthermore, the fibrous material may actually be mixed with air in the form of fiber dust or short fibers to produce a fibrous-air mixture, and / or the fibrous-air mixture may be an aerosol, in which case the fibrous material is dispersed as suspended particles in the air. Fiber materials with fibers smaller than 500 μm, preferably smaller than 200 μm, are called fiber dust. On the other hand, if the fibers of the fibrous material are smaller than 20 μm, preferably smaller than 10 μm, the fibrous-air mixture may be an aerosol. An aerosol is a mixture of suspended solid and / or liquid particles in a gas. That is, in this case, the fibrous material floats in the air and sinks very slowly, particularly not within a few seconds. In the case of an aerosol, the fibrous material is dispersed evenly and regularly in the air, which allows it to be deposited particularly evenly on the suction-type porous wall in the method described herein. To disperse the fibrous material in the air, in the case of an aerosol, all that is required is occasional active and precise movement of the fibrous-air mixture. The formation of fibrous moldings is therefore technically simple and particularly energy-efficient. Furthermore, the very small particles of fibrous material in the aerosol allow the resulting fibrous moldings to achieve excellent properties. For example, the fibrous moldings can have particularly high strength, high density, and / or high resistance to moisture or aggressive substances. However, it is also possible to process much longer fibers. This may require stronger swirling so that the fibers are evenly deposited on the porous surface of the suction mold. Longer fiber lengths are particularly desirable when processing hemp fibers.

[0029] In practice, the fiber material-air mixture may contain at least one of the following additives: sugars and / or starches, -wax, - lipids, -mineral can be further mixed.

[0030] The additives can also be starting materials for forming the fiber molding. When at least one additive is provided, the air and starting materials, i.e., the fiber material and at least one additive, are sucked into the suction mold, and the starting materials are deposited together on the porous walls of the suction mold. This produces a fiber molding in which the starting materials are evenly distributed. The additives can further improve the properties of the fiber molding, in particular, further increasing its strength, density, and / or moisture resistance.

[0031] If the spun fibrous material itself is not sufficiently wet, water can be mixed in as droplets or as steam. The water can adhere to the surface of the fibrous material and / or penetrate into the fibrous material. The adhesion of water increases the adhesion between the fibers deposited on the porous walls. Furthermore, water melts the fibrous material, thereby further increasing the adhesion of the fibers. This results in the formation of a stable fiber composite that allows the fibrous molding to be easily and reliably removed from the suction mold. This also increases the strength of the finished fibrous molding. However, the moisture content of this fibrous molding is significantly lower than when made from fiber pulp.

[0032] The starting material may further contain sugar, particularly glucose, sucrose, fructose, maltose, lactose, raffinose, or stachyose, as well as starch or a mixture of at least two of the above components. Furthermore, sugar or starch, particularly in the form of solid particles, may be mixed. Sugar or starch can also enhance adhesion between the fibers deposited on the porous walls, particularly if the sugar or starch is first heated, melted, and / or dissolved by moisture and then cooled or dried again within the fibrous molding. In this case, the sugar or starch acts as a natural adhesive that bonds the fibers of the fibrous molding. Furthermore, because the hardness of sugar crystals is typically harder than that of most fibrous materials, particularly cellulose fibers, sugar or starch can enhance the hardness and abrasion resistance of the fibrous molding.

[0033] Waxes can be mixed in the form of solid particles or droplets. In particular, carnauba wax and / or beeswax can be mixed. Carnauba wax is a very hard tropical wax with a high melting temperature (approximately 85-89°C). It has almost no odor or taste and is waterproof. In the dry state, it is very brittle and hardens within a few seconds. Its hardness makes it very stable against abrasion. It is approved for food packaging and has long been used as a coating to extend the shelf life of, for example, mangoes and sweets. Furthermore, waxes can include beeswax or other natural waxes. Biodegradable and possibly compostable wax combinations can be used, which impart high strength to the fiber molding and are particularly suitable for use with packaged foods. In addition to carnauba wax and beeswax, shellac and sugarcane wax are also suitable. Beeswax is a wax produced primarily in Europe and is not as hard as carnauba wax. Beeswax, when mixed with carnauba wax, contributes to reduced brittleness. It also has little odor or taste of its own and is approved for use with food. Its melting point is about 65°C.

[0034] Lipids can also be mixed in the form of solid particles or droplets. Lipids are hydrophobic. When lipids are included in the fibrous extrusion, they can reduce the wettability of the fibrous extrusion and / or increase the moisture-tightness (water impermeability) of the fibrous extrusion.

[0035] It should be noted that the list of additives is not exhaustive. Other additives, such as minerals or proteins, as well as pigments, can be mixed into the swirled fiber-air mixture. The additives to be mixed in are selected depending on the product to be produced and, in particular, the desired product characteristics.

[0036] The size of the additive added as solid particles or droplets is selected so that the additive is uniformly dispersed in the chamber together with the fiber material, so that the fiber material-air mixture contains the additive in an evenly dispersed state. Since the additive is deposited and compressed together with the fiber material as required, the additive added as solid particles or droplets is preferably larger than the pores in the suction-type porous wall. If the fiber material is mixed with the air as fiber dust, the particle size of the additive can preferably correspond to the particle size of the fiber material. If the fiber material-air mixture is an aerosol, the particle size of the additive can be selected to be particularly small so that the additive floats with the fibers in the chamber, thereby resulting in the fiber material-air mixture containing the additive as a whole becoming an aerosol. In this case, the particle size of the additive can be particularly less than 20 μm, preferably less than 10 μm. The water can be particularly in the form of vapor.

[0037] In practice, each additive can be stored in a separate storage container. In that case, the additive can be mixed with the fiber material before the starting material is introduced into the chamber. Alternatively, the fiber material and the additives stored in separate storage containers can be introduced into the chamber separately, which allows for particularly high flexibility. For example, the fiber material can be introduced as described above, and the additives can be mixed with air in separate storage containers to generate separate additive-air mixtures, which can be fluidized and then supplied to the chamber as separate streams through a pipeline. By swirling these streams in the chamber, the additives are uniformly mixed with the fibers and air in the chamber, generating the fiber-air mixture.

[0038] The fiber molding can be removed from the suction mold using a transfer mold. For this purpose, the transfer mold can have walls designed substantially complementary to the porous walls of the suction mold and can be pressed with a certain pressure against the fiber molding formed on the porous walls of the suction mold. This allows the fiber molding to be compressed. In particular, if the porous walls of the suction mold are formed to a large thickness by an additive manufacturing method, high strength of the formed fiber molding can already be achieved by pressing the suction mold and the transfer mold together.

[0039] In practice, the fiber molding is transferred to a press mold after being removed from the suction mold, and a counter mold can be pressed against the fiber molding placed in the press mold. The press mold has walls including a contour substantially corresponding to the contour of the porous walls of the suction mold. Preferably, the walls of the press mold are pore-free or have smaller and / or fewer pores than the porous walls of the suction mold. The walls of the press mold are preferably smooth. The counter mold is substantially complementary to the walls of the press mold and also preferably has smooth walls. The counter mold can have pores.

[0040] By pressing a counter mold against a fiber molding placed in a press mold, the fiber molding can be completely sandwiched between the walls of the press mold and the counter mold, and the fiber molding is compressed by mechanical pressure. Because the walls of the press mold and the counter mold are substantially complementary, the contour of the fiber molding can be easily varied. In particular, small steps and / or undercuts can be provided. Furthermore, by pressing the counter mold against the fiber molding, a uniform wall thickness of the fiber molding can be achieved. The surface of the fiber molding is particularly smooth by pressing, thereby enhancing the aesthetic value of the fiber molding. If water remains in the fiber molding, it can be squeezed out of the fiber molding. Unlike fiber moldings made from pulp, the fiber moldings produced according to the present invention have a very low moisture content and only require slight drying, if at all.

[0041] After the pressing of the press mold and the counter mold is complete, the press mold and the counter mold can be separated from each other, in which case the counter mold is no longer engaged with the press mold, and the fiber molding can be removed and further processed.

[0042] In practice, it is also possible to press the fiber molding in multiple stages. To this end, the fiber molding can be pressed in a first press mold with a first counter mold after pressing in the suction mold and transfer mold. If necessary, the fiber molding can be transferred to a second press mold and pressed using the second counter mold. Further pressing can also be carried out in this manner. By pressing several times in different press molds, the density can be gradually increased and / or the surface quality of the fiber molding can be gradually improved.

[0043] In practice, as already mentioned, the removal and / or transfer of the fiber molding from the suction mold to the press mold can be performed by a transfer mold. The transfer mold has walls substantially complementary to the porous walls of the suction mold. The transfer mold can be arranged on a transfer mold carrier that can be driven by an actuator and is operatively connected to a control unit. The transfer mold can be engaged with the suction mold so that the walls of the transfer mold abut against the fiber molding and remove the fiber molding from the suction mold. In this case, the transfer mold transfers the fiber molding to an intermediate storage location or a press mold. The transfer mold can also be used to transfer the fiber molding from a first press mold to another press mold. In practice, the transfer mold can be the aforementioned counterpart mold used to press the fiber molding against the porous walls of the suction mold and / or press mold.

[0044] The walls of the transfer mold can have pores, which are fluidly connected to a suction device to generate negative or positive pressure in the pores. The negative pressure sucks the fiber molding during removal from the suction mold, transfer to the press mold, and removal from the press mold. The positive pressure achieves easy release of the fiber molding from the transfer mold. At the same time, air can be blown through the porous walls of the suction mold to assist in the release of the fiber molding.

[0045] In practice, the suction mold, press mold, and / or mating mold can be heated. Heating the suction mold can serve to heat the starting materials to a predetermined temperature at which they are particularly well processed and the fibers are particularly well bonded to one another. In particular, the suction mold, press mold, and / or mating mold can be heated to a temperature of 130°C to 300°C, preferably 180°C to 240°C. These temperature ranges are higher than the melting temperatures of most waxes (especially carnauba wax and beeswax) and many sugars (especially glucose, sucrose, fructose, maltose, lactose, raffinose, stachyose) or starches, allowing the waxes and / or sugars / starch to become liquid within the fiber formed in the suction mold, press mold, and / or mating mold. If the fiber formed contains water, the water will evaporate from the fiber formed at temperatures in the above-mentioned temperature range, and the fiber formed will be dried.

[0046] In practice, the fiber preform can further be coated with a coating solution, which comprises at least one of the following components: -cellulose fibers, -casein, -whey, -Agar, -Psyllium husk may include:

[0047] If the fiber molding contains moisture, the coating can be carried out, in particular, after removing the moisture from the fiber molding. The coating of the fiber molding can be carried out, in particular, by spraying the coating solution onto the fiber molding in a suction mold, a press mold, a mating mold, and / or a coating station. Additionally or alternatively, the fiber molding can be immersed in the coating solution at the coating station or the coating solution can be poured onto it. The coating can also be applied as a partial coating to only a portion of the surface of the fiber molding.

[0048] Coatings can give the fiber molding advantageous properties. For example, they can be provided with a colored layer or a water-repellent functional layer. Coatings can also increase the density of the fiber molding and its resistance to moisture or aggressive substances. Finally, coatings can increase its strength. In this way, rigid articles such as knives or forks can be formed from the fiber molding.

[0049] The present invention also relates to an apparatus for producing fiber moldings, which comprises at least the following components: a chamber; at least one device for mixing the fiber material with air to generate a fiber material-air mixture in the chamber; - at least one suction mold with porous walls, which can be introduced into the chamber, for depositing and compressing the fiber material from the fiber material-air mixture, the contour of the porous walls corresponding to the contour of the fiber molding to be produced; - at least one suction device; It has.

[0050] At least one suction device is fluidly connected to the suction mold, thereby selectively generating negative or positive pressure in the porous wall. The device can also have multiple suction molds. In this case, the suction molds are fluidly connected to the suction device or separate suction devices. The porous wall of the suction mold can have a three-dimensional profile, particularly including multiple wall sections, and the wall sections can be formed flat, convex, and / or concave. The suction mold can have multiple wall regions, each of which forms a fiber molding. This device can be used to perform the above-mentioned method. Therefore, the description of this device includes the features and advantages thereof described above in connection with the method.

[0051] In practice, the device for mixing the fiber material with air to produce the fiber-air mixture can have a propeller and / or a vibrating membrane, the movement of which allows the starting material to be effectively and uniformly mixed with the air in the chamber as described above to produce the fiber-air mixture.

[0052] In practice, the device further comprises at least one of the following elements: at least one suction-type carrier drivable by an actuator; - separate storage containers for the fiber material, water, sugar, starch, wax and / or lipids, - at least one device for heating textile materials, water, sugar, starch, wax, at least one device for mixing water, sugar, starch and / or wax with air, - at least one transport type, at least one transport-type carrier drivable by an actuator; at least one press mold and at least one counter mold for pressing the fiber molding, at least one device for heating the suction mold, the press mold and / or the counter mold, at least one coating station for coating the fiber moldings, - at least one control unit and the above description provides a detailed explanation of these elements and their associated effects.

[0053] All elements of the apparatus may be functionally connected to at least one control unit, so that the apparatus is able to carry out the method automatically.

[0054] Further practical embodiments and advantages of the present invention will now be described in connection with the drawings. [Brief explanation of the drawings]

[0055] [Figure 1] 1 is a schematic view of an apparatus according to the invention for producing multiple fiber moldings; [Figure 2] FIG. 2 is a first partial view of the apparatus of FIG. 1 and illustrates the introduction of starting materials into the chamber. [Figure 3] FIG. 3 is a partial view of FIG. 2 and illustrates the suction of the starting material into a suction mold. [Figure 4] FIG. 3 is a partial view of FIG. 2 in which a fiber molding has been formed. [Figure 5] 3 is a partial view of FIG. 2 with a transfer device above the fiber molding. [Figure 6] 3 is a partial view of FIG. 2 and a diagram showing removal of a fiber molding from a suction mold. [Figure 7] 3 is a partial view of FIG. 2 and a diagram showing the transfer of a fiber molding in a transfer mold at a first point in time. [Figure 8] 2 is a second partial view of the device of FIG. 1 and shows the transfer of the fiber molding in the transfer form at a second point in time. [Figure 9] FIG. 10 is a third partial view of the apparatus and illustrates the pressing of the fiber molding in the press mold. [Figure 10] 10 is a partial view of FIG. 9 and shows the transfer of the pressed fiber molding to a conveyor belt. [Figure 11] FIG. 10 is a partial view of FIG. 9 and shows fiber moldings deposited on a conveyor belt. DETAILED DESCRIPTION OF THE INVENTION

[0056] 1 to 11 show the steps of the method described herein and an apparatus for carrying out the method. In the figures, an apparatus capable of simultaneously producing four fiber moldings can be seen. It should be noted that the method and apparatus according to the present invention are not limited to the simultaneous production of four fiber moldings. Rather, the number of fiber moldings produced simultaneously can be adjusted to suit the requirements. The following describes the production of one of the four fiber moldings shown in the figures, with a separate suction mold provided for each fiber molding. Suction molds with multiple surface areas can also be used, with each surface area producing one fiber molding. In the figures, identical components are designated by the same reference numerals.

[0057] To produce the fiber molding 1, a suction mold 2 is first provided. The suction mold 2 is designed as a hollow body with several walls surrounding a cavity, one of which is porous. The suction mold 2 is placed on a suction mold carrier 3 that supports several suction molds, with the porous wall 4 of the suction mold 2 facing upward. The contour of the porous wall 4 corresponds to the contour of the fiber molding 1 to be produced. The contour is designed three-dimensionally and includes several wall sections, some of which are flat and others are convex. In the example described here, the fiber molding 1 and the porous wall 4 together have the contour of an egg carton or a paper egg carton. The porous wall 4 of the suction mold 2 can be made of wire mesh or can be produced by additive manufacturing.

[0058] The suction mold 2 has suction openings (not shown) on the opposite side of the porous wall 4, which fluidly connect the pores of the porous wall 4 to a suction device (not shown). Here, the fluid connection is realized by the suction mold carrier 3 being hollow so that air can enter the suction mold carrier through openings (not shown) in the suction mold carrier 3 arranged below the suction mold 2 and flow into the suction device. The suction device is, for example, a pump.

[0059] The suction mold carrier 3 introduces the suction mold 2 into the chamber 5, which is filled with air and used to form the fiber preform 1. The suction mold 2 introduced into the chamber 5 is shown, for example, in FIG. 2. For introduction purposes, the chamber 5 has a first opening at the bottom through which the suction mold 2 is introduced, and this opening is completely closed by the suction mold carrier 3 when the suction mold 2 is introduced into the chamber. Alternatively, the suction mold carrier 3 can be positioned substantially completely within the chamber 5, with the opening being closed by a separate device.

[0060] As shown in FIG. 2 , after the suction mold 2 is introduced into the air-filled chamber 5, a fiber-air mixture 6 is introduced into the chamber 5. The fiber-air mixture 6 contains at least air and fiber material. If the fiber material does not have sufficient moisture, water can be added in the form of droplets or steam. The fiber-air mixture 6 can further contain additives such as sugar, starch, and wax. The sugar is preferably lactose, and the wax can be a mixture of carnauba wax and beeswax. The fiber material, water, sugar / starch, and wax are the starting materials for forming the fiber molded body 1. The fiber material is stored in a first storage container 7. The fiber material is dispersed into the chamber 5 in the form of solid particles through a first pipeline 8 and a second opening in the ceiling of the chamber 5. The dispersed fiber material mixes with the air already present in the chamber 5 to produce the fiber-air mixture 6. In that case, the particle size of the fibers can be 10 μm or less, so that the fiber material is suspended in the air in the chamber 5 in the form of suspended particles and the fiber material-air mixture 6 is an aerosol. Alternatively, it is also possible to use much longer fibers, for example about 200 μm in length, which settle towards the suction form after being dispersed.

[0061] Water is stored in the second storage container 9. It is heated by a first heating device (not shown) until it evaporates and then flows in the form of steam through the second pipeline 10 and into the chamber 5 through the second opening. Instead of introducing water into the chamber 5 in the form of steam, water can also be sprayed into the chamber 5 in the form of droplets. For this purpose, a pump (not shown) pumps water from the second storage container 9 through the second pipeline 10 to the second opening, where it can be sprayed into the chamber 5, for example, by a nozzle. The second pipeline 10 forms a water supply. In this case, the first heating device is not required, but can optionally be used to spray heated water droplets into the chamber 5. Sugar is stored in the third storage container 11 and is dispersed in the form of solid particles into the chamber 5 through the third pipeline 12 and the second opening. Wax is stored in the fourth storage container 13 and is dispersed in the form of solid particles into the chamber 5 through the fourth pipeline 14 and the second opening. The introduction of the different starting materials into chamber 5 can be simultaneous or sequential. If the fiber material is introduced in the form of suspended particles, the sugar and wax particles are also very small, so they remain suspended in the fiber-air mixture 6 for at least a short time. This allows the air, fiber material, steam, sugar particles, and wax particles to mix in chamber 5 and generate the fiber-air mixture 6 without significant active assistance. As they are mixed, the steam wets the fiber material and sugar, which melts the starch and sugar in the fiber.

[0062] Furthermore, it is also possible to blow the air or the fiber-air mixture 6 into the chamber 5 by means of a device in the form of a propeller or a vibrating membrane (not shown) for mixing the fiber material with the air. This allows for a more effective and uniform dispersion of the starting material in the air. In particular, the device for mixing the fiber material can be used to form a flow of the fiber-air mixture 6 in the chamber 5, directed in particular from the bottom towards the ceiling of the chamber 5, thus forming a fluidized bed. This also makes it possible to treat much larger particles that would otherwise settle in the air without a vortex means.

[0063] FIG. 3 shows the suction of the fiber-air mixture 6 through the porous wall 4 of the suction mold 2 and the compression of the fiber material and additives into the fiber preform 1 at the wall 4. To achieve this, the second opening in the ceiling of the chamber 5 is first closed. The air from the fiber-air mixture 6 is then sucked through the pores of the porous wall 4, as described above. Since the pores are smaller than the fibers, sugar particles, and wax particles, the wet fiber material, wet sugar, and wax are deposited on the porous wall 4. The fiber material, sugar, and wax are then deposited on the porous wall 4 and compressed. During the deposition of these particles, the porous wall 4 of the suction mold 2 is heated by a second heating device to a temperature in the range of 180°C to 240°C, e.g., 200°C. This causes water to rapidly evaporate from the wet starting material, resulting in the drying of the fiber preform. The evaporated water is partly sucked out by the suction mold 2 and partly supplied to the fiber-air mixture 6. At the same time, the sugar particles and wax particles deposited in the suction mold 2 melt, causing these additives to adhere to the fibers in liquid form. The fibrous body 1 shown in Figure 3 is not yet complete. After a certain suction time, the starting materials are evenly distributed, and the deposited fibrous body 1 shown in Figure 4 with the desired wall thickness is formed as described herein.

[0064] Optionally, the suction process can be carried out using a first fiber material-air mixture 6 during a first suction period, followed by a second suction period using the first fiber material-air mixture 6. The second mixture can have a different composition from the first mixture. In this way, two layers with different properties, such as color, density, water resistance, etc., are formed on the suction mold 2.

[0065] After the fiber molding 1 is formed on the porous wall 4, it is removed from the suction mold 2. For this purpose, a third opening in the side wall of the chamber 5 is first opened (FIG. 4). A transfer mold 15 mounted on a transfer mold carrier 16 is introduced into the chamber 5 through the third opening and positioned above the suction mold 2 and the fiber molding 1 (FIG. 5). The transfer mold carrier 16 is lowered, and the transfer mold 15 engages with the suction mold 2 so that its porous wall (not shown) faces the fiber molding 1 (FIG. 6). The fiber molding 1 is thus positioned between the porous wall 4 of the suction mold 2 and the porous wall of the transfer mold 15. The transfer mold 15 can be pressed against the suction mold 2 with axial pressure, thereby compressing the fiber molding 1 before removal. This is particularly true when the porous wall of the suction mold 2 is stable, for example, when it is manufactured from plastic or metal by additive manufacturing.

[0066] For removal, the fiber molded body 1 is sucked through the pores in the porous wall of the transfer mold 15 while air is blown through the pores in the porous wall 4 of the suction mold 2. In this way, the fiber molded body 1 can be easily lifted from the transfer mold 15. The fiber molded body 1 is then removed from the chamber 5 through the third opening by the transfer mold 15 (FIG. 7). The third opening is closed again, allowing the above-described method of forming a fiber molded body to be carried out again with the suction mold 2 placed in the chamber 5.

[0067] The fiber molded body 1 removed from the chamber 5 and held by the transfer mold 15 is transferred to the press mold 17 as shown in FIGS. 8 and 9. The fiber molded body 1 is pressed in the press mold 17. To apply pressure, the transfer mold 15 on which the fiber molded body 1 is placed is pressed against a porous wall (not shown) of the press mold 17 that is substantially complementary to the porous wall of the transfer mold 15. Thus, the transfer mold 15 also functions as a mating mold for the press mold 17 during pressing. The porous walls of the transfer mold 15 and the press mold 17 as a whole contain far fewer pores than the porous wall 4 of the suction mold 2. As a result, the surfaces of the porous walls of the transfer mold 15 and the press mold 17 are smoother than the surface of the porous wall 4 of the suction mold. By applying pressure, the fiber molded body 1 is compressed, moisture is squeezed out, and the fibers are tightly attached to each other, thereby improving the strength and density of the fiber molded body 1. Furthermore, the desired final geometry of the fiber molding 1 is achieved, for example by increasing the sharpness of any corners present, and the surface of the fiber molding 1 is smoothed.

[0068] After pressing the fiber shaped body 1, it is transferred by a transfer mold 15 to a conveyor belt 18 as shown in Fig. 10. When a transfer mold 17 is positioned above the conveyor belt 18, suction of the fiber shaped body 1 is terminated and air is blown through the porous walls of the transfer mold 17, causing the fiber shaped body 1 to be deposited on the conveyor belt 18 as shown in Fig. 11. The conveyor belt 18 transports the fiber shaped body 1 to a coating station (not shown), where a coating solution containing cellulose fiber, casein, whey, agar, and / or psyllium husk is sprayed onto the fiber shaped body 1. Alternatively, the conveyor belt 18 can transport the fiber shaped body 1 to an intermediate storage location.

[0069] The elements of the apparatus described above are functionally connected to a control unit that monitors and controls the parameters of the method. In particular, the control unit comprises: - opening and closing of the first, second and third openings; -Suction type carrier, - supply of starting materials to the chamber (e.g. time and amount); -Devices for heating water and suction moulds, -Devices for mixing the fibrous material with air (e.g. time and intensity) - suction of the fiber-air mixture by the suction type (e.g. time and intensity), - transport carriers (e.g., for moving and suctioning fiber moldings), -Pressure of the press mold, and -Conveyor belt movement Control.

[0070] By controlling these elements of the apparatus, the method can be carried out automatically.

[0071] The features of the invention disclosed in the specification, drawings and claims may be essential both alone and in any combination to realize the invention in its various embodiments. The invention is not limited to the above-described embodiments. The invention can be varied within the scope of the claims and in view of the knowledge of a person skilled in the art. [Explanation of symbols]

[0072] 1. Fiber molding 2 Suction type 3 Suction type carrier 4. Suction-type porous wall 5 Chambers 6. Fiber material air mixture 7. First storage container 8. First Pipeline 9 Secondary Storage Container 10 Second pipeline, supply device 11 Third storage container 12 The Third Pipeline 13 Fourth Storage Container 14 The Fourth Pipeline 15 Transfer type, counterpart type 16 Transport carrier 17 Press mold 18 Conveyor Belt

Claims

1. A method for manufacturing a fiber molded article (1), comprising the following steps, namely, - A step of placing a suction mold (2) having a porous wall (4) having a contour corresponding to the contour of the fiber molded body (1) to be manufactured inside a chamber (5), - A step of introducing a fiber material air mixture (6) into the chamber (5), wherein the fiber material is dispersed in the air in the form of solid particles, - A step of sucking the fiber material air mixture (6) through the porous wall (4) of the suction type (2), compressing the fiber material to form the fiber molded body (1) on the porous wall (4), - A step of removing the fiber molded body (1) from the suction mold (2) and the chamber (5) Includes, A method characterized in that the fibrous material mainly consists of cellulose fibers, the fibrous material is moistened, and / or water is mixed into the fibrous material-air mixture in the form of droplets or water vapor.

2. - A first fiber material air mixture (6) is introduced into and drawn into the chamber (5), thereby forming a first layer of fiber material on the porous wall (4) of the suction type (2). - At least one additional fibrous material air mixture (6) is introduced into and drawn into the chamber (5), thereby forming at least one additional layer of fibrous material on the porous wall (4) of the suction type (2), - The multiple layers of the fibrous material are compressed to form the fibrous molded body (1) on the porous wall (4), and the fibrous molded body (1) is removed from the suction mold. The method according to claim 1, characterized in that

3. The method according to claim 1 or 2, characterized in that the porous wall (4) of the suction type (2) has a three-dimensional contour including a plurality of wall sections.

4. The method according to claim 1 or 2, characterized in that the fibrous material is mixed with air in the form of fibrous dust to form the fibrous material-air mixture (6), and / or the fibrous material-air mixture (6) is an aerosol and the fibrous material is dispersed in the air as solid suspended particles.

5. The fiber material air mixture (6) contains at least one of the following additives, namely, - Sugars and / or starches, -wax, - Lipids, -mineral The method according to claim 1 or 2, characterized in that the following are further mixed.

6. The method according to claim 5, characterized in that the additives are stored in separate storage containers (9, 11, 13).

7. The method according to claim 1 or 2, characterized in that the fiber molded body (1) is removed from the suction mold (2), then transferred to a press mold (17), and a mating mold (15) is pressed against the fiber molded body (1) placed in the press mold (17).

8. The method according to claim 7, characterized in that the removal of the fiber molded body (1) and / or transfer from the suction mold (2) to the press mold (17) is performed by a transfer mold (15).

9. The method according to claim 1 or 2, characterized in that the suction mold (2), the press mold (17), and / or the mating mold (15) are heated.

10. The method according to claim 1 or 2, characterized in that the fiber molded body (1) is further coated with a coating solution.

11. Apparatus for manufacturing fiber molded articles, - Chamber (5), - To generate a fiber material-air mixture (6) in the chamber (5), at least one apparatus for mixing the fiber material with air, - At least one supply device (10) for water in the form of drops and / or water vapor, - At least one suction mold (2) having a porous wall (4) that can be introduced into the chamber (5) for depositing and compressing the fibrous material from the fibrous material-air mixture (6), wherein the contour of the porous wall (4) corresponds to the contour of the fibrous molded body being manufactured, - At least one suction device and A device equipped with the following features.

12. The apparatus according to claim 11, characterized in that the apparatus for mixing the fibrous material with air has a propeller and / or a vibrating membrane.

13. At least one of the following characteristics, namely, - At least one suction-type carrier (3) that can be driven by an actuator, - Separate storage containers for the fibrous material, water, sugar, wax, and / or lipids (7, 9, 11, 13), - At least one apparatus for heating the fiber material, the water, the sugar and / or the wax, - At least one apparatus for mixing water, sugar, and / or wax with air, - At least one transport type (15), - At least one transportable carrier (16) that can be driven by an actuator, - At least one press mold (17) and at least one mating mold (15) for pressurizing the fiber molded body, - At least one device for heating the suction mold, the press mold, and / or the mating mold, - At least one coating station for coating the fiber molded body, - At least one control unit The apparatus according to claim 11 or 12, characterized by having the following features.

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