Method for filling a cylindrical container with clay and packaging unit for the container filled with clay

Abstract

According to the invention, a method for filling a container of standardized geometry with clay comprises the following steps: d) extruding the clay using an extruder; e) pumping the clay plasticized using the extruder through a conduit from the outlet of the extruder using a pump and / or by the pressure created in the clay using the extruder into the opening of the container and into an outlet opening (18) provided on the underside of a piston member (20) adapted to fit into the opening of the container and into the internal space (8) of the container (2), the internal space (8) being substantially cylindrical and with a substantially constant cross section of the internal space (8) and the opening along a cylindrical axis (10); f) guiding the piston member in the direction of the cylindrical axis using a device with a drive configured to apply pressure towards the inside of the container to the clay introduced below the piston member.

Description

[Technical field]

[0001] The present invention relates to a method for filling a container, as well as to a container filled with clay. [Background technology]

[0002] A plastic material for plastic modelling is so-called clay.

[0003] Clay is a material used for model making, especially in car design, but also for example character designers for movies, cartoons and video games, industrial designers, artists and architects use it to model their three-dimensional shapes. This material is a special modification of the known Plastiline for this purpose.

[0004] Clays are generally wax-based substances that are plastically deformable at a certain temperature (usually above normal room temperature). As a filler, sulfur is used in many embodiments. Clays often have a brownish or gray color, which allows easy visibility for inspecting the modeled shape, especially during modeling by the designer.

[0005] Before a new car model is launched on the market, the process of shaping the new bodywork is time-consuming and laborious. Sketches, drawings and 3D-CAD models are created. Today, however, models of the vehicle are also produced at various scales, typically 1:10 and 1:4 to 1:1, since this allows the overall and detailed shape and proportions to be determined very well in practice. Furthermore, the shape and proportions of the model made of clay can be produced and finished with a precise and detailed imitation, since clay can be cut, sliced, carved or ground, for example, due to its high form stability at room temperature. However, it is also possible to apply material later, in which case the clay is heated (to a temperature not exceeding two digit Celsius range) for example by means of a hot air blower or a heat radiator in the area of ​​the intended material application. Within this upper temperature range, in particular at about 60-70°C, the clay is plastically deformable, but does not become liquid or merely pasty and flowable, but bonds substantially homogeneously with the additionally applied clay material of approximately the same temperature. The carefully processed and substantially homogeneous transition area is cooled and becomes shape-stable again, whereupon it can be processed again by removal. The clay can also be lacquered using known method steps. This means that models can be produced from the clay that are very close in shape and surface to the intended product, or even identical to it.

[0006] For such models, a wooden or metal frame is generally first produced, to which a plate (e.g. a foam plate), for example made of polyurethane, is attached, on which clay is applied - generally also in layers in order to produce the desired clay layer thickness - as the outer layer of the model to be modeled as described above, in such a way that a basic model can be formed everywhere possible with at least the size of the final model.

[0007] This application is still widely carried out by hand. Generally, heated clay (below 60° C.) is applied by hand kneading movements, worked with spatula-shaped tools or blades, and within the abovementioned temperature range of the clay, where the clay is plastically deformable and therefore adheres well to the frame plate. In order to achieve better adhesion there are various known means, such as for example applying a sealant (for example as a paint or spray, also for fixing dirt) and / or forming recesses and / or barb structures, for example by drilling or cutting grooves, in which the clay can be held in a shape-locking manner in addition to being applied. During and after this application, if it has not yet completely cooled, the desired surface shape of the clay can already be formed, even if only partially, by plastic shaping or at least prepared by corresponding preforming and contouring.

[0008] There is currently widespread development of equipment with which clay can be applied mechanically. For this purpose, it has proven advantageous to prepare the clay not exclusively in the form of bars or rods, as is conventional, but in larger (also transportable) packaged units, especially since the throughput of clay during this processing is significantly higher. In this sense, attempts have already been made to process clay from drums. However, for this experimental process, the drums were filled with clay by hand, since clay as a plastic material cannot be pumped in the same way as a liquid using known methods. Summary of the Invention [Problem to be solved by the invention]

[0009] The problem underlying the present invention is to provide clay in larger packaged units with reproducible quality and as far as possible without entrapped air. This problem is solved by a method having the features of claim 1 and a product having the features of claim 10. [Means for solving the problem]

[0010] According to the invention, a method for filling containers of standardized geometry (containers having substantially the same geometric shape) with clay is proposed, as well as containers filled with clay by such a method according to the invention.

[0011] According to the invention, the container in which the method according to the invention is provided has an opening and a substantially cylindrical interior space, the opening as well as the interior space having a constant cross section along the cylindrical axis.

[0012] The method according to the invention comprises the following steps: a) extruding clay using an extruder; b) pumping the clay plasticized by the extruder through a conduit by means of a pump and / or by means of an extrusion pressure created in the clay by means of the extruder into an outlet opening provided on the underside of a piston member adapted to fit into the opening of the container and into the interior space of the container; c) guiding the piston member in the direction of the cylindrical axis by means of a device having a drive adapted to apply pressure to the clay introduced below the piston member towards the interior of the container; Includes.

[0013] An extruder is a device consisting of a plastic processing means, which, as is known, conveys, compresses and extrudes plastically deformable substances by means of (at least) one screw. Extruders were initially developed for rubber processing and are widely used for thermoplastics and even now for pasty foods. In the case of screw extruders, the different thread cross-sectional geometries over the length of the extruder screw allow the conveying, compression, degassing, mixing and homogenization of the substances being processed in the extruder. However, in the present invention, the extruder is used to "knead" the clay, thereby heating it, plasticizing it, homogenizing it, degassing it if necessary - that is, making it pumpable, so to speak - and pumping it under pressure into a pump and through the lines by means of this pump (or even, in particular, without a pump, only by the pressure created in the clay by means of the extruder). The clay may optionally be in the extruder, especially in the last method step of its preparation, but it may also be introduced into the extruder (i.e. especially from an intermediate store, for example in the known rod or bar form), especially into a container for the filling according to the invention. For this purpose, a pretreatment step, for example grinding and / or heating, is highly advantageous.

[0014] According to the invention, the clay is then conveyed into an outlet opening provided on the underside of a "piston member" which is adapted according to the invention to fit into the opening and into the interior space of the vessel for which it is provided, i.e. a cylindrical vessel in the sense already described.

[0015] When removing highly viscous liquids from drums of cylindrical basic shape in plastics processing, so-called "drum follower plates" are used, in particular to avoid pumping of trapped air. Such drum follower plates are, for example, in the present invention "piston elements", components in the form of pistons, which, possibly with a circumferential piston seal, fit through a cylindrical opening into the drum, i.e. into the cylindrical inner space of the container, in which case a sealing ring can seal the component against the drum wall. The drum follower plate is inserted into the drum (after removal of the actual drum cover) and is possibly equipped with a sealing ring, which can seal the drum follower plate against the drum wall over its entire circumference. In this way, the drum follower plate forms an airtight and rigid cover over the liquid and, together with the drum or container, completely and tightly encloses the liquid. The drum follower plate is then actively (guided and driven) pressed against the material in plastics processing. In the known manner, the drum follower plate also slides downwards during material removal, either by its own weight or by negative pressure. For this purpose, the container used in this context is a drum, i.e. its internal space has a substantially tubular, in particular cylindrical, inner contour (possibly with, for example, reinforcing longitudinal or circumferential embossments or other deviations from the mathematical cylindrical shape that are not in contradiction with this technical principle according to the invention), in which case the inner contour also opens substantially outwardly, without tapering, into the external opening of the internal space, i.e. into the drum opening. However, in the present invention, a piston member is used in order to avoid the inclusion of air according to step c) according to the present invention when filling the container (but not when unloading). That is to say, preferably with a pneumatic cylinder as drive device, the piston member is guided in the direction of the cylindrical axis of the internal space of the container via a device with a linear drive device. These are configured to exert pressure on the clay introduced under the piston member towards the inside of the container.

[0016] In the present invention, the piston member may be adapted to the geometry of the container such that in step c) there is an annular gap between the piston member and the inner surface of the cylindrical circumferential wall of the container. The annular gap may then be sealed by a seal or the annular gap may be used for air evacuation without a seal. However, in particular (but not exclusively) a seal may be used to create a negative pressure in the container and / or under the piston member for air evacuation by means of a vacuum pump.

[0017] The transport of clay to the outlet opening on the underside of the piston member is possible according to the invention by means of a twin unit, i.e. a branch in the supply line to the piston member leads to a second such supply line and to a second such piston member as well as to the drive. That is to say, according to the invention, a first container can be filled by the first piston member through the first supply line, while the filled container is removed, closed and subsequently transported around the second piston member, on which the next container is also attached in preparation for the next filling. That is to say, in this case, after the end of filling of a container by the first supply conduit and the first piston member, the branch can be "switched" immediately and the filling of the container already prepared there can be started by the second piston member, without having to wait for the removal of the filled container and the attachment of the new container to be filled around the first piston member.

[0018] The duct between the pump and the piston member may comprise a (particularly rigid) duct section in which a static and / or dynamic mixer is arranged.

[0019] The mixing of flowing components, for example in the production of plastics, for example before the introduction of the plastics into the sprue of a mould or even before the application of the plastics to a fibre fabric or textile fabric for the production of GRP or CFRP, is widely carried out in its interior space by tubular guide means (mixers) with shaping elements (vortex elements) which in various ways deflect, deflect, locally stagnate, turbulent and / or vortex the flowing fluids and thus mix them. In this case, as is known, the number of feed lines leads into the mixer, in particular the number of flowing components which are to be mixed to form the plastic. In this case, it has proven and become established that for a particularly homogeneous and complete mixing of the components, the vortex elements are not only arranged stationary in the tubular guide means (static mixers), but are also arranged to rotate (dynamic mixers). In this case, the known device for mixing at least two flowable components by means of a dynamic mixer has at least two component supply lines and a rotary drive with a drive shaft, which is adapted to fluid-tightly connect a tubular passage guide to the component supply lines and to rotary drive connect the drive shaft with the mixer insert via a rotary drive connection structure of the mixer insert (having a support bar with at least one vortex member and adapted to be inserted into the passage guide) when the mixer insert is inserted into the passage guide and the passage guide is connected to the component supply lines. Such a rotary drive connection structure on the known mixer insert is usually an opening located substantially radially to the axis of rotation, into which a hook on the end of the drive shaft engages to form the drive connection. The mixer insert and the passage guide can (also in the present invention) be one-time or disposable items. However, in the present invention, these (static or dynamic) mixers are preferably not used for mixing the components, but are advantageously used for additionally shearing and / or homogenizing the flowably plasticized clay according to the present invention, which also prevents deterioration of the clay, for example by visual changes in the clay and by mixing separation, for example in the form of stripe formation.For example, the clay can be sheared using equipment equipped with a (static or dynamic) mixer, for example also between the extruder and the pump.

[0020] To adjust the plasticity and thus the flowability of the clay in the extruder, the pressure in the clay can be measured in the region of the extruder outlet and the pump inlet, the differential pressure can be calculated by means of an electronic data processing device, and the pressure in the extruder can be adjusted by means of a regulating device, which can adjust the pump speed via this differential pressure, i.e. with the differential pressure as regulating variable and the pump speed as manipulated variable.

[0021] In order to improve the flowability of the clay, a heating device may be used to at least partially temperature-condition the pump and / or the flanges and / or the piping and / or the pipe section between the extruder and the pump, and / or to at least partially temperature-condition the piston plate and / or the bottom of the vessel and / or the circumferential surface of the vessel.

[0022] In order to be able to check the state of the clay, i.e. downstream of the extruder, upstream and / or downstream of the pump, possibly upstream and / or downstream of the mixer and / or upstream of the piston element, a line branch can be provided there in each case (e.g. also with a bypass for this purpose), so that the clay can be taken off as a sample.

[0023] The pump is preferably a screw spindle pump, which has proven advantageous for pumping very viscous liquids (to which clays are not classified), but possibly also a gear or piston pump, for example.

[0024] These and other advantages and features of the present invention will be further illustrated with reference to the following drawings of one embodiment of the invention. [Brief description of the drawings]

[0025] [Figure 1]1 is a schematic diagram showing an apparatus for carrying out the method according to the invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The figure shows how clay 4 is filled into a container 2 (i.e. in particular a drum 2) of standardised cylindrical geometry.

[0027] It will be seen that the container 2 has an opening 6 and a cylindrical interior space 8, the opening 6 as well as the interior space 8 having a constant cross section along the (cylindrical) cylindrical axis 10.

[0028] The illustrated method comprises the following steps: a) extruding clay 4 using an extruder 12; b) pumping the plasticized and pressurized clay 4 using the extruder 12 through a line 16 using a pump 14 into an outlet opening 18 on the underside of a piston member 20 adapted to fit into the opening 6 of the vessel 2 and into the cylindrical interior space 8 of the vessel 2; c) guiding the piston member 20 in the direction of the cylindrical axis 10 using a device comprising a drive 24 configured to exert a pressure on the clay 4 introduced below the piston member 20 towards the inside of the container 2; Includes.

[0029] The extruder 12 is a device for conveying, compressing and extruding the clay 4 via the screw 25. The different cross-sectional geometry of the thread over the length of the extruder screw 25 allows for conveying, compressing, degassing, mixing and homogenizing the clay 4 being processed in the extruder 12. In the extruder 12, the clay 4 is in the last method step of its production, which includes, in particular, mixing, stirring and homogenizing the main components of the clay 4 (not shown) possibly in another device (not shown) in line upstream of the extruder 12. The extruder 12 is now further used to "knead" the clay 4, thereby heating, plasticizing, homogenizing and degassing it, so to speak, making it pumpable, pumping it under pressure into the pump 14, i.e. into the screw spindle pump 14 and pumping it through the line 16 by the screw spindle pump 14.

[0030] The clay 4 is then pumped into an outlet opening 18 provided in the underside of a "piston member" 20. This so-called drum follower plate 20 is adapted to fit into the opening 6 of the vessel 2 in which the piston member 20 is provided, and into the interior space 8 of the vessel 2.

[0031] The drum follower plate 20 is a component in the form of a piston, here with a circumferential piston seal 26, which fits through the cylindrical opening 6 into the drum 2, i.e. into the cylindrical inner space 8. The drum follower plate 20 is inserted into the drum 2 (after removal of the actual drum cover (not shown)). The seal 26 seals the drum follower plate 20 against the drum wall all around. In this way, the piston member 20 forms an airtight and rigid cover on the clay 4 in the drum and, together with the drum 2, completely and tightly surrounds it. The drum follower plate 20 is then actively (guided and driven) pressed against the material 4. In the present invention, the piston member 20 is used when filling the container 2 (but not when unloading) in order to avoid the inclusion of air according to step c) above. That is, by means of a pneumatic cylinder as the drive device 24, the piston member 20 is guided via a device 22 with linear bearings in the direction of the cylindrical axis 10 of the inner space 8 of the container. These are arranged to apply pressure to the clay 4 introduced below the piston member 20 towards the inside of the vessel 2. For the purpose of de-airing, a negative pressure is additionally created in the vessel 2 below the piston member 20 by means of a vacuum pump 28.

[0032] The line 16 between the pump 14 and the piston member 20 comprises a rigid pipe section 30 in which a (dynamic) mixer 34 is arranged, which is driven in rotation by a motor 32. In this case, the vortex member of the mixer 34 is not so much used for mixing the components, but for additionally shearing and / or homogenizing the clay 4, which has been advantageously plasticized according to the invention to be flowable. This also prevents deterioration of the clay 4, for example by visual changes in the clay 4 and by mixing separation, for example in the form of the formation of stripes.

[0033] In order to adjust the plasticity and therefore the flowability of the clay 4 in the extruder 12, the pressure in the clay is measured in the region of the extruder outlet 36 and the pump inlet 38, the differential pressure is calculated by means of an electronic data processing device 40 and the pressure in the extruder is adjusted using the adjusting device 40.

[0034] In order to further improve the flowability of the clay 4, a heating device 42 is used to partially temperature-condition the pump 14, the lines 16 and the pipe section 30, and also partially temperature-condition the piston plate 20 and the vessel 2. [Explanation of symbols]

[0035] 2 Containers, drums 4. Clay 6 Opening of container 8. Inner space of the container 10 Cylinder axis 12 Extruder 14 Pump 16 Conduit 18 Exit opening 20 Piston member 22 Linear guide device 24 Drive unit 25 Extruder screw 26 Piston seal 28 Vacuum Pump 30 Sections 32 Motor 34 Dynamic Mixer 36 Extruder outlet 38 Pump inlet 40 Electronic data processing devices, adjustment devices 42 Heating device

Claims

1. A method for filling a container (2) of standardized geometric shape with clay (4), comprising the following steps: a) extruding said clay (4) using an extruder (12); b) pumping the clay (4) plasticized by the extruder (12) from the outlet of the extruder (12) through a line (16) by means of a pump (14) and / or by means of the pressure created in the clay (4) by means of the extruder (12) into an outlet opening (18) provided on the underside of a piston member (20) adapted to fit into the opening (6) of the container (2) and into the internal space (8) of the container (2), the internal space (8) being substantially cylindrical and with a substantially constant cross section of the internal space (8) and of the opening along a cylindrical axis (10); c) guiding the piston member (20) in the direction of the cylindrical axis (10) using a device comprising a drive (24) configured to exert a pressure on the clay (4) introduced below the piston member (20) towards the inside of the container (2); The method includes:

2. 2. The method according to claim 1, wherein the piston member (20) is adapted to the geometry of the container (2) such that in step c) there is an annular gap between the piston member (20) and the inner surface of the cylindrical peripheral wall of the container (2).

3. 3. The method according to claim 2, wherein the annular gap between the piston member (20) and the inner surface of the cylindrical peripheral wall of the container (2) is sealed by a seal or is used for venting without a seal.

4. 3. The method according to claim 2, wherein the annular gap between the piston member (20) and the inner surface of the cylindrical circumferential wall of the container (2) is sealed by a seal, and a negative pressure is created in the container (2) and / or under the piston member (20) by means of a vacuum pump (28) for air evacuation.

5. 5. The method according to claim 1, wherein the pipeline (16) comprises a pipeline section (30) in which a static mixer and / or a dynamic mixer (34) is arranged.

6. 6. The method according to claim 1, further comprising measuring the pressure in the clay (4) at the extruder outlet (36) and at the pump inlet (38), calculating the differential pressure by means of an electronic data processing device, and regulating the pressure in the extruder (12) by means of a regulating device using the differential pressure as the regulating variable and the pump speed as the manipulated variable.

7. 7. The method according to claim 1, further comprising at least partially temperature-conditioning the pump (14) and / or the flange and / or the pipe line (16) and / or the pipe section (30) between the extruder (12) and the pump (14) and / or at least partially temperature-conditioning the piston plate and / or the bottom and / or the circumferential surface of the vessel (2) using a heating device (42).

8. The method according to any one of the preceding claims, wherein the pump (14) is a screw spindle pump.

9. 9. The method according to claim 1, wherein the linear drive is a pneumatic cylinder.

10. A cylindrical container (2) filled with clay (4) by the method according to any one of claims 1 to 9.

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