MELTING TRANSPORT DEVICE

Description

[0001] The invention relates to a melt transport device.

[0002] DE 10 2007 011 253 A1 discloses a casting device with a melting container for metallic materials. An injector is arranged on the underside of the melting container, which has an opening for dispensing the molten metal. A closing device is also provided, which serves to close the opening. JP 2000 042723 A describes a similar device.

[0003] The casting device known from DE 10 2007 011 253 A1 has the disadvantage that the sealing device can become contaminated, which means that its tightness can no longer be guaranteed after some use. Furthermore, the casting device and the casting process have the disadvantage that, due to the described design of the sealing device, the flow behavior and / or flow velocity of the molten metal during casting can only be inadequately controlled. The casting device and the casting process also have the disadvantage that, due to the positioning of the sealing device above the lance, the molten metal has a significant impact height on the mold, which can damage the mold. Additionally, the large drop height can cause turbulence and thus oxide inclusions in the casting. All of this leads to the production of inferior castings.

[0004] The object of the present invention was to overcome the disadvantages of the prior art and to provide a device by means of which improved cast workpieces can be produced.

[0005] This problem is solved by a device according to independent claim 1. Further embodiments are described in dependent claims 2-12.

[0006] The melting vessel has a gas-tight outer shell.

[0007] A melt receiving vessel could be arranged within the gas-tight outer shell. This receiving vessel could be made of a first material, while the outer shell, at least in sections, could be made of a second material. The first and second materials have different material properties. Separating the gas-tight outer shell from the melt receiving vessel offers the advantage that the outer shell and the receiving vessel can have different mechanical properties. Thus, the receiving vessel could be made of a material designed for high temperatures or for receiving a liquid melt. The receiving vessel would only need to withstand minimal mechanical forces. In particular, it could be provided that the mechanical forces are absorbed or transferred to the gas-tight outer shell.Additionally, the gas-tight outer shell can be made of a material that is easy to weld, thus enabling a gas-tight welding of the individual components.

[0008] In particular, it can be provided that the gas-tight outer shell serves to accommodate the melt receiving vessel, wherein the melt receiving vessel is placed in the gas-tight outer shell and the weight of the melt receiving vessel acts on the gas-tight outer shell in the form of a tensile force.

[0009] Furthermore, it may be provided that the second material of the outer shell comprises a metallic material, in particular a steel material, and / or that the first material of the molten metal receiving vessel comprises a fiber-reinforced material, in particular a glass fiber-reinforced material. This offers the advantage that a steel material exhibits good weldability. In addition, a steel material is well suited to withstanding tensile forces. A glass fiber-reinforced material, if sufficiently strong, can exhibit high temperature resistance and is therefore well suited for receiving molten metal.

[0010] Furthermore, the glass fiber-reinforced material of the melt receiving vessel may comprise a calcium silicate, a quartz glass, a silicon carbide, or a zirconium silicate. In particular, it may be provided that glass fibers are embedded in a base material made of calcium silicate, a quartz glass, a silicon carbide, or a zirconium silicate.

[0011] Furthermore, the outer shell is designed to comprise a shell and a base flange, with the shell being coupled to the base flange, in particular by welding. This offers the advantage that the base flange can serve as a connection point for additional components.

[0012] In particular, the casing may be formed from a sheet of steel. The sheet of steel may be wound into a thin-walled hollow cylinder. In particular, the hollow cylinder may have an axial weld seam by means of which a first longitudinal end and a second longitudinal end of the wound sheet of steel are welded together.

[0013] Furthermore, the outer casing includes a bottom cover, which is detachably connected to the base flange by means of fasteners. This allows easy access to the interior of the gas-tight outer casing by loosening and removing the bottom cover. This facilitates easy replacement of the melting vessel or provides easy access to the melting vessel when needed. Additionally, this design allows the melting vessel to rest against the bottom cover, or for the bottom cover to serve as a mounting and support for the melting vessel.

[0014] Furthermore, a seal may be provided between the bottom cover and the bottom flange. In particular, the seal may be in the form of a graphite gasket.

[0015] All seals of the outer shell can be designed in the form of a graphite seal.

[0016] The spout is designed as a lance, which is positively engaged in a central recess in the base cover. This offers the advantage that the lance can be easily replaced or coupled to the melting vessel.

[0017] Furthermore, it can be advantageous for the lance to have a connecting element and for the melt receiving vessel to have a contact surface, with the connecting element being pressed against this surface by means of the bottom cover. This measure allows for simple coupling or connection of the lance to the melt receiving vessel.

[0018] Furthermore, a seal may be provided between the connecting element and the contact surface. In particular, the seal may be designed in the form of a graphite seal.

[0019] Furthermore, the melt receiving vessel can be pre-tensioned towards the bottom cover by means of spring elements. This offers the advantage that the contact surface of the melt receiving vessel is pressed against the lance's connecting element with a specific pre-tension force, thus ensuring a tight connection between the lance's connecting element and the contact surface of the melt receiving vessel. This also ensures the secure retention of the melt receiving vessel within the outer casing. Additionally, the use of spring elements compensates for differing thermal expansion rates between the melt receiving vessel and the outer casing, preventing damage to the melting vessel during molten metal collection.

[0020] A spring element within the meaning of this document can be, for example, a steel spring or, more generally, a resilient material. A spring element within the meaning of this document can also be a pneumatic spring.

[0021] As an alternative to using a spring element, it is also conceivable that an actuator, such as a pneumatic cylinder, could be used to pre-tension the melt receiving vessel.

[0022] Furthermore, the outer shell may include a head unit, the head unit being coupled to the shell, in particular by welding. Specifically, the head unit may serve to accommodate essential components, such as a gas valve, etc. Furthermore, the head unit may serve to connect the melt vessel to a handling device, such as a handling robot.

[0023] According to a particular design, it is possible for the spring elements to be supported on the head unit.

[0024] According to an advantageous embodiment, a plug may be provided, wherein the plug is slidably arranged in a plug axial direction on the melt container and serves to close the spout. This offers the advantage that the spout can be closed by means of the plug or the flow rate of melt can be regulated. In particular, it may be provided that the plug is arranged in the receiving chamber of the melt receiving vessel and that the plug interacts with an opening of the melt receiving vessel.

[0025] In an alternative design variant, it can also be provided that the plug interacts with a constriction in the lance or with another component.

[0026] In particular, it can be advantageous if the plug is slidably attached to the head unit by means of an actuator. This has the advantage that the plug can remain on the head unit of the outer casing when the melt receiving vessel is replaced. This results in the simplest possible design and easy replacement of the melt receiving vessel.

[0027] Furthermore, the plug may be provided with a heating element arranged within it. This has the advantage of largely preventing the molten metal from freezing at the plug.

[0028] Furthermore, the plug can be provided with an outer wall containing an embedding powder, in particular a magnesium oxide powder, within which the heating element is embedded. This design offers the advantage that the heating element can be contained within the plug, preventing damage to the heating element caused by the high temperature fluctuations during the casting process.

[0029] Another advantageous design involves the heating element being coupled to a power supply cable, with the power supply cables being routed freely between the head unit and the plug, thus allowing relative movement of the plug to the head unit. This has the advantage of ensuring that the electrical power required for the operation of the heating elements can be transported to them.

[0030] In an alternative design variant, it can be provided that sliding contacts for current transmission are formed between the head unit and the plug.

[0031] Furthermore, it may be provided that the power supply cable is sheathed with heat-resistant electrical insulation, the insulation being designed for maximum temperatures between 900°C and 250°C.

[0032] A connection element as defined in this document is advantageously a flange, but can also be designed as a conical component. The connection element applies the sealing force required to ensure a tight seal between the lance and the melt receiving vessel. Furthermore, the connection element can define the geometric position, such as coaxiality and the position of the outlet opening relative to the melt transport device. This facilitates easy replacement of the melt transport device.

[0033] To better understand the invention, it is explained in more detail with reference to the following figures.

[0034] They each show, in a highly simplified, schematic representation: Fig. 1 a schematic representation of a first embodiment of a melt transport device; Fig. 2 a sectional view of an embodiment of a plug; Fig. 3 a cross-sectional view of the plug along section line II-II from Fig. 2 Fig. 4 a perspective view of a first embodiment of a bottom cover; Fig. 5 a further embodiment of a connection of a lance to the melt receiving vessel; Fig. 6 a further embodiment of a melt transport device with two lances; Fig. 7 a further embodiment of a melt transport device with two lances and two separate gas-tight chambers.

[0035] It should be noted at the outset that in the differently described embodiments, identical parts are provided with the same reference numerals or component designations, and the disclosures contained in the entire description can be applied analogously to identical parts with the same reference numerals or component designations. Furthermore, the positional designations chosen in the description, such as top, bottom, side, etc., refer to the figure directly described and illustrated, and these positional designations must be applied analogously to the new position if the position changes.

[0036] Fig. 1 shows a first embodiment of a melt transport device 1, which serves to transport melt 2.

[0037] The melt transport device 1 has a melt container 3 in which a melt receiving chamber 4 is formed, which serves to receive the melt 2.

[0038] Furthermore, the melt transport device 1 can include a spout 5 which is coupled to the melt container 3. The spout 5 can be designed as an integral part of the melt container 3. Alternatively, the spout 5 can also be designed as a separate component coupled to the melt container 3. The spout 5 has a pouring opening 6 through which the melt 2 received in the melt container 3 can flow from the melt transport device 1 into a mold.

[0039] Furthermore, a gas valve 7 can be provided, which is fluidically connected to the melt receiving chamber 4 and which is designed to regulate the gas input into the melt receiving chamber 4. The gas valve 7 is arranged above a maximum fill level 8, so that no melt 2 can flow into the gas valve 7. The maximum fill level is selected such that when the melting vessel 3 is filled with melt 2 up to the maximum fill level 8, a gas-filled space remains in the melt receiving chamber 4, in which a pressure can be set by means of the gas valve 7.

[0040] Furthermore, a pressure sensing device 9 can be provided, by means of which an internal pressure in the melt receiving chamber 4 can be detected. Thus, the gas pressure in the melt receiving chamber 4 can be specifically adjusted by the gas valve 7.

[0041] Furthermore, a suction line 10 may be provided, which can be coupled to a vacuum pump 11. The gas valve 7 can also be arranged in the area of ​​the suction line 10, or be designed to allow gas to flow into the melt receiving chamber 4 in a controlled manner via the suction line 10.

[0042] As from Fig. 1 It can further be seen that the melt transport device 1 may have a siphon 12.

[0043] The siphon 12 can be arranged between the melt receiving chamber 4 and the pouring opening 6.

[0044] As from Fig. 1 It can also be seen that the spout 5 is designed in the form of a lance 13. The siphon 12 can be arranged on the underside of the lance 13.

[0045] As from Fig. 1It is further shown that the melting vessel 3 has a gas-tight outer shell 14. A melt receiving vessel 15 can be arranged inside the gas-tight outer shell 14, which can serve to receive the melt 2.

[0046] In particular, the melt receiving vessel 15 may be designed in the form of a crucible, with the melt receiving chamber 4 being defined or limited by the melt receiving vessel 15. Furthermore, the melt receiving vessel 15 may have an outlet opening 16, which may be located in the lower region of the melt receiving vessel 15. In particular, the outlet opening 16 may be designed as a central opening in the melt receiving vessel 15.

[0047] In particular, it may be provided that a vacuum can be created within the outer shell 14 in order to allow the melt 2 to flow out of the melt receiving chamber 4 in a controlled manner or to allow the melt 2 to be drawn into the melt receiving chamber 4.

[0048] How particularly good looks Fig. 1 It can be seen that the outlet opening 16 is formed in a base 17 of the melt receiving vessel 15. The base 17 of the melt receiving vessel 15 can be conical, so that as the melt level falls, the melt 2 is directed towards the outlet opening 16.

[0049] As from Fig. 1 As further shown, the melt receiving vessel 15 may be designed to be open at the top. In an embodiment not shown, a splash guard may be provided on the upper side of the melt receiving vessel 15.

[0050] Furthermore, it is provided that the outer shell 14 has a jacket 18. The jacket 18 can be coupled to a head unit 19. In particular, it can be provided that the jacket 18 is welded to the head unit 19. In a first embodiment, it can be provided that the jacket 18 is rolled from a flat sheet into a hollow cylinder, wherein the opposing ends of the rolled sheet can be welded together by means of a weld seam.

[0051] Furthermore, a base flange 20 is provided, which is welded to the shell 18. In particular, the base flange 20 may be designed to receive a base cover 21. Specifically, the base cover 21 may be coupled to the base flange 20 by means of fasteners 22. Such fasteners 22 may, for example, be in the form of screws. Specifically, it may be provided that both the base flange 20 and the base cover 21 have a pattern of holes in the form of through holes 23, which serve to insert the fasteners 22.

[0052] Furthermore, it may be provided that a central recess 24 is formed in the base cover 21, which can serve as a passage for the melt 2. In particular, it may be provided that the lance 13 corresponds to the central recess 24. Furthermore, it may be provided that the lance 13 has a connecting element 25, which can be received in a recess 26 of the central recess 24. The connecting element 25 can bear against a contact surface 27 of the melt receiving vessel 15.

[0053] Furthermore, a spring element 29 may be arranged between the head unit 19 and a top surface 28 of the melt receiving vessel 15. In particular, several spring elements 29 may be arranged around the circumference between the head unit 19 and the melt receiving vessel 15. The spring elements 29 serve to press the melt receiving vessel 15 against the bottom cover 21.

[0054] As from Fig. 1As further shown, it may be provided that a plug 30 is formed which can serve to close the outlet opening 16. In particular, it may be provided that the plug 30 is designed to be displaceable in a plug axial direction 31 relative to the melt receiving vessel 15. The plug 30 can be displaceable in the plug axial direction 31 by means of an actuator 32.

[0055] Furthermore, a heating element 33 may be arranged in the plug 30, which is designed to heat the plug 30. In particular, the heating element 33 may be coupled to a power supply cable 34, which serves to transmit the electrical energy for heating the heating element 33. The power supply cable 34 may be arranged on the head unit 19.

[0056] As from Fig. 1As further shown, a vessel holder 47 may be arranged on the underside of the outer shell 14. The vessel holder 47 can serve to receive or hold the melt receiving vessel 15 when the bottom cover 21 is removed from the outer shell 14 to replace the lance 13. In particular, the vessel holder 47 may be designed to be parallel to the bottom cover 21.

[0057] Fig. 2 shows a sectional view of an embodiment of the plug 30. Fig. 3 shows the corresponding cross-sectional view according to section line III - III from Fig. 2 .

[0058] In the presentation of the Figures 2 and 3 The plug 30 is shown in its closed position, so that it protrudes into the outlet opening 16.

[0059] As from Fig. 3As can be seen, the plug 30 may have an outer wall 35, which may be hollow and cylindrical. A rod-shaped heating element 33 may be accommodated within the outer wall 35. Furthermore, an embedding powder 36 may be formed between the outer wall 35 and the rod-shaped heating element 33. The embedding powder 36 may serve to compensate for temperature-related thermal expansion between the outer wall 35 and the heating element 33.

[0060] How particularly good looks Fig. 3As can be seen, the plug 30 may have an outer diameter 37. The outlet opening 16 may have an inner diameter 38. In particular, the outer diameter 37 of the plug 30 may be smaller than the inner diameter 38 of the outlet opening 16. This allows an annular gap 39 to form between the plug 30 and the inner wall of the outlet opening 16. The provision of the annular gap 39 allows the plug 30 to be inserted into or close the outlet opening 16 without touching the melt receiving vessel 15.

[0061] Fig. 4 Figure 1 shows a first embodiment of the base cover 21. As shown from Fig. 4As can be seen, the bottom cover 21 may have a recess 40 in the area of ​​the central recess 24. The recess 40 may be designed such that the connecting element 25 of the lance 13 can be positively engaged in it. In particular, it may be designed that, in the installed state of the bottom cover 21, the recess 40 is formed on an upper side or facing the melt receiving chamber 4.

[0062] Furthermore, it may be provided that tabs 41 are formed in which the through holes 23 are arranged. The tabs 41 may project radially outwards.

[0063] As from Fig. 4As further shown, a step 42 may be provided which corresponds to the base flange 20. The step 42 allows the base cover 21 to be centered in the base flange 20. In particular, a first sealing groove 43 may be formed in the area of ​​the step 42. The first sealing groove 43 may be formed in an axial end face of the step 42 and serve to receive the axial seal.

[0064] Furthermore, a second sealing groove 44 may be formed in the step 42. The second sealing groove 44 may be arranged in a circumferential surface of the step 42 and serve to receive a radial seal.

[0065] As from Fig. 4As further shown, it may be provided that recesses 45 are formed in the base cover 21. The recesses 45 can serve to reduce the weight of the base cover 21. In particular, it may be provided that webs 46 are formed between the recesses 45.

[0066] Fig. 5 A sectional view shows a further embodiment of a detail for connecting the lance 13 to the melt receiving vessel 15, where again the same reference numerals or component designations are used for identical parts as in the preceding illustrations. Figures 1 to 4 to be used. To avoid unnecessary repetition, reference is made to the detailed description in the preceding sections. Figures 1 to 4 pointed out or referenced.

[0067] As from Fig. 5As can be seen, a mounting sleeve 48 of the melt receiving vessel 15 may protrude through the bottom cover 21. The melt receiving vessel 15 may have a shoulder that corresponds to the step 42 in the bottom cover 21. This shoulder, together with the step 42, can serve for the axial positioning of the melt receiving vessel 15. Furthermore, the mounting sleeve 48 may have an external thread for interaction with a union nut 49. The union nut 49 can then be used to hold the lance 13 to the melt receiving vessel 15.

[0068] In particular, the union nut 49 may have a retaining ring 50 which engages positively with the connecting element 25, thereby pressing the connecting element 25 against the contact surface 27 by means of the union nut 49. In particular, a first seal 51 may be arranged between the connecting element 25 and the contact surface 27. Furthermore, a second seal 52 may be arranged between the retaining ring 50 of the union nut 49 and the connecting element 25 of the lance 13. Furthermore, a third seal 53 may be arranged between the union nut 49 and the base cover 21.

[0069] In particular, it can be provided that, when the union nut 49 is screwed on or the lance 13 is fastened, a seal is achieved between the lance 13 and the melt receiving vessel 15, between the lance 13 and the union nut 49, and between the union nut 49 and the bottom cover 21. This ensures, on the one hand, a melt-tight connection between the lance 13 and the melt receiving vessel 15. On the other hand, this measure also creates a gas-tight connection of the outer casing 14. This allows a negative pressure to be generated in the melt receiving chamber 4.

[0070] Fig. 6 Figure 1 shows a further embodiment of the melt transport device 1, wherein again the same reference numerals or component designations are used for identical parts as in the preceding figures. Figures 1 to 5 to be used. To avoid unnecessary repetition, reference is made to the detailed description in the preceding sections. Figures 1 to 5pointed out or referenced.

[0071] As from Fig. 6 It can be provided that a first lance 13a and a second lance 13b are formed. Furthermore, it can be provided that a first melt receiving vessel 15a and a second melt receiving vessel 15b are formed. Both melt receiving vessels 15a and 15b can be arranged within the outer shell 14.

[0072] Furthermore, it can be provided that the lances 13a and 13b are each cranked and pivotable relative to the outer shell 14 about a vertical axis. This vertical axis can be located at the center of the connection between the 13a and 13b and the melt receiving vessel 15a and 15b. This measure allows the distance between the two pouring openings 6a and 6b of the two lances 13a and 13b to be adjusted relative to each other.

[0073] Fig. 7Figure 1 shows a further embodiment of the melt transport device 1, wherein again the same reference numerals or component designations are used for identical parts as in the preceding figures. Figures 1 to 6 to be used. To avoid unnecessary repetition, reference is made to the detailed description in the preceding sections. Figures 1 to 6 pointed out or referenced.

[0074] As from Fig. 7 As can be seen, it can be provided that the first lance 13a and the second lance 13b are formed. Furthermore, it can be provided that the first melt receiving vessel 15a and the second melt receiving vessel 15b are formed, and that the lances 13a and 13b are each assigned to their respective melt receiving vessels 15a and 15b. Both melt receiving vessels 15a and 15b can be arranged within the outer shell 14. As can be seen from Fig. 7As further shown, it can be provided that the first melt receiving vessel 15a and the second melt receiving vessel 15b are each housed in their own separate chamber. Thus, the first melt receiving vessel 15a and the second melt receiving vessel 15b can be subjected to different vacuum pressures in order to control the casting process independently. In particular, different melts can be received in the first melt receiving vessel 15a and the second melt receiving vessel 15b.

[0075] As from Fig. 7 It can be seen that the pouring openings 6a and 6b of the two lances 13a and 13b are arranged at different heights.

[0076] The exemplary embodiments show possible embodiment variants, whereby it should be noted at this point that the invention is not limited to the specifically illustrated embodiment variants, but rather various combinations of the individual embodiment variants are also possible and this possibility of variation lies within the skill of the person skilled in this technical field due to the teaching on technical action by the present invention.

[0077] The scope of protection is defined by the claims. However, the description and drawings must be consulted for the interpretation of the claims. Individual features or combinations of features from the different embodiments shown and described can, in themselves, represent independent inventive solutions. The problem underlying these independent inventive solutions can be found in the description.

[0078] All references to value ranges in this description are to be understood as encompassing any and all sub-ranges thereof, e.g., the reference 1 to 10 is to be understood as including all sub-ranges, starting from the lower limit 1 and the upper limit 10, i.e., all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g., 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0079] Finally, for the sake of clarity, it should be noted that, for a better understanding of the structure, some elements have been shown not to scale and / or enlarged and / or reduced in size. Reference numeral list 1 Melt transport device 30 Plug 2 melt 31 Plug axial direction 3 Melting container 32 actuator 4 Melt receiving chamber 33 heating element 5 spout 34 power supply cable 6 spout 35 exterior wall 7 Gas valve 36 embedding powder 8 Maximum fill level 37 Outer diameter plug 9 Pressure detection device 38 Inner diameter of outlet opening 10 Suction line 39 annular gap 11 vacuum pump 40 Reduction 12 siphon 41 tab 13 lance 42 gradation 14 outer shell 43 first sealing groove 15 Melt receiving vessel 44 second sealing groove 16 outlet opening 45 Exclusion 17 bottom melt receiving vessel 46 web 18 Coat 47 Container holder 19 Head unit 48 Mounting bracket 20 base flange 49 union nut 21 Bottom cover 50 retaining ring 22 Fasteners 51 first seal 23 Through hole 52 second seal 24 central recess 53 Third seal 25 Connection element 26 in-depth 27 Site area 28 Top of melt receiving vessel 29 spring element

Claims

1. A melt transport device (1) comprising a melt container (3), in which a melt receiving space (4) is formed, and a spout (5), which is coupled to the melt container (3), wherein the spout (5) comprises a spout orifice (6) which is flow-connected to the melt receiving space (4), wherein the spout (5) is formed as a lance (13), wherein a gas valve (7) is formed, which is flow-connected to the melt receiving space (4) and which is configured for regulating the introduction of gas into the melt receiving space (4), wherein the melt container (3) comprises a gas-tight outer shell (14), characterized in that the outer shell (14) comprises a jacket (18) and a base flange (20), wherein the jacket (18) is coupled to a base flange (20), wherein the outer shell (14) comprises a base cover (21) which is detachably coupled to the base flange (20) by means of fastening means (22), wherein the lance (13) is received in a positive-locking manner in a central recess (24) in the base cover (21).

2. The melt transport device (1) according to claim 1, characterized in that a melt receiving vessel (15) is arranged inside the gas-tight outer shell (14), wherein the melt receiving vessel (15) is formed from a first material and the outer shell (14) is formed at least in some sections from a second material, wherein the first material and the second material have different material properties to one another.

3. The melt transport device (1) according to claim 2, characterized in that the second material of the outer shell (14) comprises a metallic material, in particular a steel material, and / or that the first material of the melt receiving vessel (15) comprises a fiber-reinforced material, in particular a glass fiber-reinforced material.

4. The melt transport device (1) according to claim 1, characterized in that the lance (13) has a connecting element (25) and that the melt receiving vessel (15) has a contact surface (27), wherein the connecting element (25) is pressed against the contact surface (27) by means of the base cover (21).

5. The melt transport device (1) according to claim 4, characterized in that the melt receiving vessel (15) is pretensioned in the direction of the base cover (21) by means of spring elements (29).

6. The melt transport device (1) according to one of claims 1 to 5, characterized in that the outer shell (14) comprises a head unit (19), wherein the head unit (19) is coupled, in particular welded, to the jacket (18).

7. The melt transport device (1) according to claims 5 and 6, characterized in that the spring elements (29) are supported on the head unit (19).

8. The melt transport device (1) according to one of the preceding claims, characterized in that a stopper (30) is formed, wherein the stopper (30) is formed on the melt container (3) so as to be displaceable in an axial stopper direction (31) and serves to close the spout (5).

9. The melt transport device (1) according to claims 6 and 8, characterized in that the stopper (30) is displaceably attached to the head unit (19) by means of an actuator (32).

10. The melt transport device (1) according to claim 8, characterized in that the stopper (30) has a heating element (33) arranged in the stopper (30).

11. The melt transport device (1) according to claim 8 or 9, characterized in that the stopper (30) has an outer wall (35), wherein an embedding powder (36), in particular a magnesium oxide powder, is received inside the outer wall (35),wherein the heating element (33) is embedded in the embedding powder (36).

12. The melt transport device (1) according to claim 9 and one of claims 10 to 11, characterized in that the heating element (33) is coupled to current supply cables (34), wherein the current supply cables (34) are guided freely between the head unit (19) and the stopper (30) in such a way that a relative movement of the stopper (30) to the head unit (19) is made possible.