Method and casting installation for casting components

Abstract

The invention relates to a method and a casting system for casting components with a casting compound, wherein an elastic film is arranged on a model by means of a vacuum, wherein the model is arranged in a molding box (25), wherein the molding box is filled with a molding material (27), wherein a mold (32) is formed by applying a vacuum to the molding material in the molding box, wherein the model is removed and a cavity (33) is formed in the mold, wherein a casting compound (11) is filled into the cavity and cured to form a component, wherein the component is demolded.

Description

[0001] The invention relates to a method and a casting system for casting components with a casting machine, wherein an elastic film is arranged on a model by means of a vacuum, wherein the model is arranged in a molding box, wherein the molding box is filled with a molding material, wherein a mold is formed by applying a vacuum to the molding material in the molding box, wherein the model is removed and a cavity is formed in the mold, wherein a casting compound is filled into the cavity and cured to form a component, wherein the component is demolded.

[0002] In the prior art processes and casting systems for casting components with casting compounds, a mold is typically used as a permanent mold. The permanent mold can be designed as a formwork or similar structure into which the casting compound is introduced. Such permanent molds with fresh concrete as the casting compound are used particularly for the production of prefabricated components in construction, for example, made of concrete. The production of such components with permanent molds in large quantities has proven to be cost-effective.

[0003] Nevertheless, even components manufactured in relatively small quantities are produced using such permanent molds. Due to the wide variety of different components, for example, a series of precast concrete components, it is necessary to manufacture and store a large number of permanent molds for the production of this series of components. Due to the high manufacturing costs of permanent molds, they are regularly stored for long periods of time in case the component in question needs to be produced again in the future. The production and storage of permanent molds therefore results in costs that significantly increase the price of components manufactured in small quantities.

[0004] It is therefore an object of the invention to propose a method and a casting system for casting components with a casting compound which enables cost-effective production of components.

[0005] This object is achieved by a method having the features of claim 1 and a casting plant having the features of claim 19.

[0006] In the method according to the invention for casting components with a casting compound, an elastic film is arranged on a model by means of a vacuum, the model being arranged in a molding box, the molding box being filled with a molding material, a mold being formed by applying a vacuum to the molding material in the molding box, the model being removed and a cavity being formed in the mold, a casting compound being filled into the cavity and cured to form a component, the component being demolded.

[0007] In the method according to the invention, a mold into which the casting compound is poured is formed using molding material placed in a molding box. First, a model of the component to be manufactured is made, with the elastic film being drawn onto the model using a vacuum. The model is then placed inside the molding box, and the molding box is filled with the molding material. A vacuum is then created in the molding box, with the molding material being stabilized by the vacuum so that the mold is formed. The model can now be removed, leaving a cavity in the mold corresponding to the model. The film remains in the mold and lines the cavity. The cavity can now continue to be filled with the casting compound, with the casting compound then hardening to form the component in the mold. Finally, the component can simply be removed from the mold.In the process, the form is destroyed again, so that this is a lost form.

[0008] The method according to the invention eliminates the need for formwork or permanent molds to produce components from casting compounds, thus eliminating the costly production and storage of permanent molds. It is merely intended that at least a single model of the component to be manufactured is produced, which is, however, considerably simpler than producing a multitude of permanent molds. The model can be made from a cost-effective, lightweight material, for example, using 3D printing from plastic, so that prolonged storage of the model is not worthwhile. This makes it possible to produce components from casting compounds cost-effectively, even in small quantities. Furthermore, the film in the mold makes it possible to produce the components with a high surface quality.In addition, geometries and free forms can be realized that would not be possible with a permanent mold or would only be possible with great effort, for example components with undercuts.

[0009] An elastic film can also be attached to a further model by means of a vacuum, wherein the further model can be arranged in a further molding box, wherein the further molding box can be filled with a molding material, wherein one mold half can be formed by applying a vacuum to the molding material in the further molding box, wherein the further model can be removed and a cavity can be formed in the mold half, wherein the mold can be formed by assembling the molding box with the further molding box. Consequently, it can be provided that the mold is formed from two mold halves, which in turn are formed by molding boxes with molding material. If the mold alone has a molding box, the cavity can be formed with an opening whose contour corresponds to a contour of the component and which forms a substantially flat surface of the component.If the mold has two mold boxes, the cavity can be formed between the two mold boxes so that the component is completely contained within the mold. The models then also represent model halves of the component. Furthermore, at least one sprue for filling the casting compound can be formed in one of the mold halves. This makes it possible to manufacture components from casting compounds with complex geometries.

[0010] At least one core can be inserted into the cavity. The core can, for example, also be made of molding material and have a film or a similar coating or layer suitable for separating the molding material from the casting compound. The use of one or more cores makes it possible to produce particularly complex components with casting compounds that, for example, have openings, cavities, or undercuts.

[0011] Reinforcement, preferably structural steel and / or fibers, can be inserted into the cavity. The reinforcement can make the component particularly strong, for example, capable of withstanding tensile loads. Furthermore, metal or plastic components, such as anchor plates or the like, can also be inserted into the mold.

[0012] Cement, concrete, mortar, gypsum, or polymer concrete can be used as the casting compound. It is essential that the casting compound can cure or set at a temperature typical for these materials. The process is not limited to the use of these materials; other suitable casting compounds can also be used.

[0013] Sand, gravel, fibers, and / or pigments can be used as aggregates. Suitable aggregates are those that ensure the flowability of the casting compound so that it can be poured into the mold and fill the cavity. The aggregates can increase the strength of the component. Furthermore, the component can be produced in a desired color, for example, by adding pigments. Aggregates that cause the casting compound to set quickly can also be used. The component can then be removed from the mold after a short time and dried or fully cured outside of the mold.

[0014] Sand with a binding agent, model sand or similar, can be used as the molding material. Model sands have a comparatively fine grain, although sand with a coarser grain can also be used. This is made possible by the film covering the sand and the casting compound being separated from the film by the sand or molding material during casting. Also, no special requirements are placed on the molding material with regard to high temperatures, so that a comparatively cost-effective molding material can be used. Because the molding material is not exposed to significant wear, for example from high temperatures, and essentially does not come into contact with the casting compound, i.e. is hardly contaminated, the molding material can be recycled without further processing.

[0015] The model can be arranged on a model carrier, wherein the model carrier and / or the model can have channels that can open into a surface of the model carrier and / or the model facing the molding material, wherein the channels can be subjected to the vacuum. The model carrier can, for example, be formed by a plate whose dimensions essentially correspond to the dimensions of a frame of the molding box. The plate can be double-walled such that a cavity is formed within the plate to which the vacuum can be applied. Alternatively, it can be provided that the plate is formed with channels that run through the plate and to which the vacuum can be applied. Channels can then be formed in the model carrier or the plate, which connect the cavity or the channels running in the model carrier with the surface facing the molding material.This makes it possible to apply a vacuum to the channels via at least one connection on a model carrier. The film can then be sucked in so far that it adheres completely to the model and the model carrier. The channels opening into the surface of the model carrier can be arranged or formed at suitable positions depending on the shape of the model. After the film has been applied, the vacuum can be maintained until the mold is formed.

[0016] The film can be attached to a support frame and drawn onto the model or the model carrier using a vacuum. The support frame can then have dimensions that essentially correspond to the dimensions of a frame of the molding box. The film can be attached to the support frame using an adhesive material. The film can then be heated so that the film becomes easily formable. The support frame with the film can then be placed on the molding box, with the film then being drawn onto the model and the model carrier using the vacuum. Finally, the support frame is separated from the film and removed.

[0017] After the molding box has been filled with the molding material, a further film can be attached to the support frame and pulled onto the molding box using the vacuum created in the molding material so that the molding material is dimensionally stable. The molding box can be designed with a frame or in the shape of a frame so that the molding box can be easily filled with the molding material. In this case, the molding material can be compacted by means of vibration, shaking or the like. The amount of molding material can be such that the molding material is essentially flush with an upper edge of the molding box. The further film can be attached to the support frame using an adhesive and the support frame can be placed on the molding box so that the further film rests against the molding box.A vacuum can then be created within the molding material, allowing the additional film to adhere to the molding box, and the vacuum created within the molding material stabilizes the molding material to ensure its dimensional stability. To ensure the dimensional stability of the molding material, the vacuum can be maintained at least until the casting compound sets.

[0018] The film can have a perforation at least in the area of ​​the cavity, whereby the cavity is vented by means of the vacuum via the perforation during casting. If the vacuum is continuously created in the molding material, i.e. if a vacuum pump is connected to the molding box, the vacuum can be maintained even in the event of minor leaks. The film can therefore also be designed with a perforation that allows the cavity to be vented by the vacuum in the molding material. This is particularly advantageous if, after the casting compound has been poured, there are still air pockets in it that could impair the strength of the component. A perforation is particularly easy to produce and allows effective venting of the cavity.

[0019] Furthermore, risers can be provided in the mold. These risers can be used to ensure and control that the cavity is completely filled with the casting compound.

[0020] Optionally, the film inside the cavity can be coated with a coating. The coating can be similar to the casting compound or consist of a base material of the casting compound. Coating the film with the coating enables the production of components with particularly high surface quality.

[0021] The vacuum can be created in the molding box using a pump and preferably subsequently shut off using a valve. The pump can be a vacuum pump, and a valve can be provided in a suction line between the pump and the molding box, which can be used to shut off the vacuum. It is then no longer necessary to permanently maintain the vacuum using the pump. Since the film is regularly pressed tightly against the molding box, there are few or no leakage losses, so the vacuum is permanently created even without the pump running, thus maintaining the stability of the mold.

[0022] After the mold has been formed, casting material can be filled into the cavity, whereby the casting material can be compacted by vibrating the mold, a vibration bottle in the casting material in a sprue of the mold and / or by applying a vacuum. By vibrating or shaking the mold, the casting material can be compacted so that any air pockets present in the casting material are also removed. Alternatively or additionally, a so-called vibration bottle can be immersed in the sprue of the mold or the casting material located there and the casting material can be set into vibration by means of the vibration bottle, so that the casting material can also be compacted in this way. Alternatively or additionally, it can also be provided to apply a vacuum to the casting material.This can be achieved, for example, by positioning a bell above a mold opening, for example, at the sprue, through which air contained in the casting compound is extracted. This can prevent air pockets in the component.

[0023] After the casting compound has hardened, the vacuum in the molding box can be switched off, breaking any bond in the molding material and allowing the component to be demolded. This demolding of the component can take place above a grate or similar, as the molding material can then fall through the grate and be easily collected for recycling. The film can then be separated from the molding material. The component can then be removed from the grate. Furthermore, the molding box can be shaken to facilitate the breaking of the bond in the molding material.

[0024] The mold material from the mold can be used to create another mold using a molding machine. The molding machine can then be set up so that after the component has been demolded, the mold material is collected, possibly homogenized, and cleaned of film, thus preparing it for further use. Further processing of the mold material is not mandatory, as the mold material does not necessarily come into contact with the casting compound. If this does happen, the casting compound, which has then hardened and binds the mold material, can be removed from a quantity of mold material by sieving. The mold material prepared in this way can be used to create further molds for the production of components. The molding machine then enables cyclical, recurring use of the mold material.

[0025] The component can be a precast concrete element, a semi-precast concrete element, a cast stone, or similar. Such concrete components can then be manufactured cost-effectively in small quantities, particularly since the production and storage of a large number of permanent molds is not required.

[0026] The casting system according to the invention for casting components from a casting compound comprises a molding machine and a casting machine, wherein the molding machine comprises at least one molding box and at least one manipulator for handling a model of the component and / or the at least one molding box, wherein an elastic film can be arranged on the model by means of a vacuum by means of the molding machine, wherein the model can be arranged in the molding box by means of the molding machine, wherein the molding box can be filled with a molding material by means of the molding machine, wherein a mold can be formed by applying a vacuum to the molding material in the molding box by means of the molding machine, wherein the model can be removed by means of the molding machine in such a way that a cavity is formed in the mold, wherein a casting compound can be filled into the cavity by means of the casting machine in such a way that the casting compound is cured to form a component, wherein the component can be demolded by means of the molding machine.For the advantages of the casting system according to the invention, reference is made to the description of the advantages of the method according to the invention. Further advantageous embodiments of the casting system emerge from the descriptions of the features of the subclaims referring back to method claim 1.

[0027] Preferred embodiments of the invention are explained in more detail below with reference to the accompanying drawings.

[0028] The Fig. 1a bis 1k show a possible sequential process for producing a component 10 by casting with a casting compound 11. The component 10 here consists of concrete, and the casting compound 11 consequently consists of fresh concrete. The process can also be carried out with other flowable, hardenable casting compounds.

[0029] The characters Fig. 1a bis 1k show simplified schematic diagrams and sectional views of the process, which is carried out with a molding machine not shown in detail here. Fig. 1a shows a model 12 arranged on a model carrier 13. A cone 14 is arranged on the model 12 and serves to form a sprue 15. The model carrier 13 is essentially formed by a plate 16 within which an interior space 17 is formed. A pump 18 for forming a vacuum and a valve 19 are connected to the interior space 17. The model 12 is firmly mounted on a flat surface 20 of the plate 16. Furthermore, channels 21 are formed in the plate 16 and in the model 12, which open into the surface 20 and a surface 22 of the model 12, respectively. When a vacuum is formed by means of the pump 18, air is sucked in through these channels 21.

[0030] First, an elastic film 23 is arranged on the surface 22 of the model 12 or the surface 20 of the plate 16. The film 23 is attached to a support frame 24 and is heated to improve the formability of the film 23. The support frame 24 is, as shown in the Fig. 1a shown, together with the film 12, is brought closer to the model carrier 13 and placed on the model carrier 13 in such a way that the film 23, as shown in the Fig. 1b shown, lies tightly against the surfaces 20 and 22. The vacuum is created by means of the pump 18, so that the film 23 is firmly fixed to the surfaces 20 and 22. The support frame 24 is removed again. By means of the valve 19, the vacuum can be maintained even without operation of the pump 18 when the valve 19 is closed. This facilitates handling of the model carrier 13.

[0031] Further, as in the Fig. 1c As can be seen, a molding box 25 is placed on the model carrier 13. The model 12 is now arranged within the molding box 25. The molding box 25 is essentially formed by a frame 26.

[0032] According to the Fig. 1d The molding box 25 is filled with molding material 27, which consists of model sand. Compaction of the molding material 27 is preferably carried out by means of vibration or shaking. The amount of molding material 27 is such that the molding box 25 is completely filled. By means of the support frame 24, a further film 28, which is attached to the support frame 24, is then arranged on the molding box 25, so that the further film 28 completely covers the molding material 27, as can be seen from Fig. 1e can be seen. During the application of the additional film 28, a vacuum is created within the molding material 27 within the molding box 25 by means of the pump 18. As a result, the additional film 28 adheres tightly to the molding material 27 and the frame 26. By creating the vacuum by means of the pump 18, the molding material 27 is further compressed and solidified. The molding box 25 has a valve 29, which can be shut off after the vacuum has been created, so that the pump 18 is no longer absolutely necessary to maintain the vacuum.

[0033] As from the Fig. 1f can be seen, the model carrier 13 can now be removed together with the model 12. The vacuum in the channels 21 is removed by opening the valve s19 on the model carrier 13, so that the film 23 remains on the mold box 25.

[0034] The mold or mold half 30 thus formed is now combined with a mold half 31 to form a mold 32. The mold halves 30 and 31 are pressed together with a force as shown in the Fig. 1g schematically shown, pressed together. Mold half 31 was designed here in the manner of mold half 30. However, it is also possible for mold half 30 or mold half 31 alone to form a mold if the geometry of a component does not absolutely require the use of two mold halves.

[0035] The Fig. 1h shows the finished mold 32 with a cavity 33 formed therein and the sprue 15. A surface 34 of the cavity 33 is completely covered by the film 23.

[0036] In the following, as can be seen from Fig. 1i As can be seen, the casting compound 11 is filled into the cavity 33 of the mold 32. A casting machine 35, which is only partially shown here, can be used for this purpose. A casting machine is understood here to mean a device that is at least suitable for providing and handling the casting compound 11.

[0037] After the casting compound 11 has been filled into the cavity 33, the casting compound 11 can be compacted by vibrating the mold 32, as shown schematically in Fig. 1j is shown. In this way, any air pockets present in the casting compound 11 can be removed. After the casting compound 11 has solidified, i.e. has set to such an extent that the casting compound 11 is dimensionally stable, the then formed component 10 is demolded. This is done by opening the valves 29 on the respective mold boxes 25 and thus dissolving the respective vacuum. The molding material 27 located in the mold boxes 25 is then no longer dimensionally stable and can fall out of the mold 32 simply by shaking it. In this case, the component 10 can be caught by means of a grate, for example, and then completely cured or dried, if necessary. A sprue 36 is also removed mechanically here, so that finally the Fig. 1k finished component 10 shown.

Claims

1. A method for casting components with a casting compound, wherein an elastic film (23) is arranged on a model (12) by means of a vacuum, wherein the model is arranged in a molding box, wherein the molding box is filled with a molding material (27), wherein a mold (32) is formed by applying a vacuum to the molding material in the molding box, wherein the model is removed and a cavity (33) is formed in the mold, wherein a casting compound (11) is filled into the cavity and cured to form a component (10), wherein the component is demolded.

2. Method according to claim 1, characterized by thatan elastic film (23) is arranged on a further model (12) by means of a vacuum, wherein the further model is arranged in a further molding box (25), wherein the further molding box is filled with a molding material (27), wherein a mold half (30, 31) is formed by applying a vacuum to the molding material in the further molding box, wherein the further model is removed and a cavity (33) is formed in the mold half, wherein the mold is formed by assembling the molding box with the further molding box.

3. Method according to claim 1 or 2, characterized by that at least one core is inserted into the cavity (33).

4. Method according to one of the preceding claims, characterized by that a reinforcement, preferably structural steel and / or fibers, is inserted into the cavity (33).

5. Method according to one of the preceding claims, characterized by thatcement, concrete, mortar, gypsum or polymer concrete is used as casting material (11).

6. Method according to one of the preceding claims, characterized by that sand, gravel, fibers and / or pigments are used as aggregate.

7. Method according to one of the preceding claims, characterized by that sand with a binding agent, model sand or the like is used as the molding material (27).

8. Method according to one of the preceding claims, characterized by that the model (12) is arranged on a model carrier (13), wherein the model carrier and / or the model has channels (21) which open into a surface (20, 22) of the model carrier and / or the model facing the molding material (27), wherein the channels are subjected to the vacuum.

9. Method according to one of the preceding claims, characterized by thatthe film (23) is attached to a support frame (24) and is pulled onto the model (12) and the model carrier (13) by means of the vacuum.

10. Method according to claim 9, characterized by that after filling the molding box (25) with the molding material (27), a further film (28) is attached to the support frame (24) and pulled onto the molding box by means of the vacuum formed in the molding material, such that the molding material is dimensionally stable.

11. Method according to one of the preceding claims, characterized by that the film (23) has a perforation at least in the region of the cavity (33), wherein the cavity is vented by means of the vacuum via the perforation during casting.

12. Method according to one of the preceding claims, characterized by that in the form (32) risers are formed.

13. Method according to one of the preceding claims, characterized by thatthe film (23) is coated with a size within the cavity (33).

14. Method according to one of the preceding claims, characterized by that the vacuum in the molding box (25) is formed by means of a pump (18) and is preferably subsequently shut off by means of a valve (29).

15. Method according to one of the preceding claims, characterized by that after the formation of the mold (32), the casting compound (11) is filled into the cavity (33), wherein the casting compound is compressed by means of vibration of the mold, a vibration bottle in the casting compound in a sprue (15) of the mold and / or application of a vacuum.

16. Method according to one of the preceding claims, characterized by that after the casting compound (11) has hardened, the vacuum in the molding box (25) is switched off, whereby a bond of the molding material (27) is dissolved and the component (10) is demolded.

17. Method according to one of the preceding claims, characterized by that the molding material (27) of the mold (32) is used by means of a molding machine to form a further mold (32).

18. Method according to one of the preceding claims, characterized by that the component (10) is a prefabricated concrete part, semi-prefabricated concrete part, concrete stone or the like.

19. A casting system for casting components from a casting compound, wherein the casting system comprises a molding machine and a casting machine (35), wherein the molding machine comprises at least one molding box (25) and at least one manipulator for handling a model (12) of the component and / or the at least one molding box, wherein an elastic film (23) can be arranged on the model by means of a vacuum by means of the molding machine, wherein the model can be arranged in the molding box by means of the molding machine, wherein the molding box can be filled with a molding material (27) by means of the molding machine, wherein a mold (32) can be formed by applying a vacuum to the molding material in the molding box by means of the molding machine, wherein the model can be removed by means of the molding machine such that a cavity (33) is formed in the mold, wherein a casting compound (11) can be filled into the cavity by means of the casting machine such that the casting compound is cured to form a component (10),whereby the component can be demolded using the molding machine.

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