MELT TRANSPORTATION DEVICE

Description

The invention relates to a melt transport device.

DE 10 2007 011 253 A1 discloses a casting device having a melt container for metallic materials. On the bottom side of the melt container, an injector is arranged, which has an orifice for discharging the melt. Moreover, a closing device is formed, which serves to close the orifice.

The casting device known from DE 10 2007 011 253 A1 has the disadvantage that the closing device can become soiled, as a result of which its tightness can no longer be guaranteed after some use. The casting device and/or the casting method also has the disadvantage that the flow behavior and/or the flow rate of the melt during casting can only be inadequately controlled by the described structure of the closing device. The casting device and/or the casting method also has the disadvantage that due to the positioning of the closing device above the lance, the melt has a high impact height on the mold, which can damage the mold. In addition, the high drop height can cause turbulence and thus oxide inclusions in the casting. All this leads to the production of inferior castings.

The object of the present invention was to overcome the shortcomings of the prior art and to provide a device and a method by means of which improved castings can be produced.

This object is achieved by means of a device and a method according to the claims.

The invention relates to a melt transport device comprising a melt container, in which a melt receiving space is formed, and a spout, which is coupled to the melt container, wherein the spout comprises a spout orifice which is flow-connected to the melt receiving space. Moreover, a gas valve is formed, which is flow-connected to the melt receiving space and which is configured for regulating the introduction of gas into the melt receiving space.

Furthermore, it may be useful if the melt container has a gas-tight outer shell, wherein a melt receiving vessel is arranged inside the gas-tight outer shell, wherein the melt receiving vessel is formed from a first material and the outer shell 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. A structural separation of the gas-tight outer shell and the melt receiving vessel entails the advantage that the outer shell and the melt receiving vessel can have different mechanical properties. Thus, the melt receiving vessel can be made of a material that is configured for high temperatures and/or for receiving a liquid melt. The melt receiving vessel only needs to absorb low mechanical forces in this regard. In particular, it may be provided that the mechanical forces are absorbed in and/or transferred to the gas-tight outer shell. In addition, the gas-tight outer shell can be made of a material that is easy to weld, so that gas-tight welding of the individual components is possible.

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

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 melt receiving vessel comprises a fiber-reinforced material, in particular a glass fiber-reinforced material. This entails the advantage that a steel material has good weldability. Moreover, a steel material is well suited for absorbing tensile forces. A glass fiber-reinforced material can have a high temperature resistance with sufficient strength and can therefore be well suited for holding molten material.

Furthermore, it may be provided that the glass fiber-reinforced material of the melt receiving vessel comprises 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 of calcium silicate, a quartz glass, a silicon carbide or a zirconium silicate.

In addition, it may be provided that the outer shell comprises a jacket and a base flange, wherein the jacket is coupled, in particular welded, to a base flange. This entails the advantage that the base flange can be used to connect other components.

In particular, it may be provided that the jacket is formed from a steel sheet. The steel sheet can be wound into a thin-walled hollow cylinder. In particular, it may be provided that the hollow cylinder has an axial weld seam by means of which a first longitudinal end and a second longitudinal end of the coiled steel sheet are welded together.

Another advantageous embodiment is that the outer shell comprises a base cover which is detachably coupled to the base flange by means of fastening means. By this measure, it can be achieved that the interior space of the gas-tight outer shell is easily accessible by loosening and removing the base cover. As a result, the melt container can be easily replaced and/or the melt container can be easily accessible if required. In addition, by this measure, it can be achieved that the melt container can be supported on the base cover and/or that the base cover can be used to hold and support the melt container.

Furthermore, it may be provided that a seal is arranged between the base cover and the base flange. In particular, it may be provided that the seal is provided in the form of a graphite seal.

All seals of the outer shell can be provided in the form of a graphite seal.

According to an advancement, it is possible for the spout to be configured as a lance, wherein the lance is received in a positive-locking manner in a central recess in the base cover. This entails the advantage that the lance can be arranged on the melt container so that it can be easily replaced and/or can be coupled to the melt container.

Furthermore, it can be useful if the lance has a connecting element and that the melt receiving vessel has a contact surface, wherein the connecting element is pressed against the contact surface by means of the base cover. By this measure, a simple coupling and/or connection of the lance to the melt receiving vessel can be received.

Furthermore, it may be provided that a seal is arranged between the connecting element and the contact surface. In particular, it may be provided that the seal is provided in the form of a graphite seal.

In addition, it may be provided that the melt receiving vessel is pretensioned in the direction of the base cover by means of spring elements. This entails the advantage that by this measure, it can be achieved that the contact surface of the melt receiving vessel is pressed against the connecting element of the lance with a certain preload force, wherein a tight connection can be achieved between the connecting element of the lance and the contact surface of the melt receiving vessel. Furthermore, by this measure, it can be achieved that the melt receiving vessel is securely held within the outer shell. In addition, the use of spring elements can compensate for different thermal expansions of the melt receiving vessel and the outer shell in order to avoid damage to the melt container when melt is being received.

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

As an alternative to the use of a spring element, it is also conceivable that an actuator, such as a pneumatic cylinder, is used to pretension the melt receiving vessel.

Furthermore, it may be provided that the outer shell comprises a head unit, wherein the head unit is coupled, in particular welded, to the jacket. In particular, it may be provided that the head unit serves to receive essential components, such as a gas valve, etc. Furthermore, it may be provided that the head unit is used to connect the melt container to a manipulation device, such as a manipulation robot.

According to a particular embodiment, it is possible for the spring elements to be supported on the head unit.

According to an advantageous advancement, it may be provided that a stopper is formed, wherein the stopper is configured to be displaceable in an axial stopper direction on the melt container and serves to close the spout. This entails the advantage that the stopper can be used to close the spout and/or regulate the amount of melt flowing out. In particular, it may be provided that the stopper is arranged in the receiving space of the melt receiving vessel and that the stopper cooperates with an orifice of the melt receiving vessel.

In an alternative embodiment variant, it can also be provided that the stopper cooperates with a narrowing in the lance or with a further component.

In particular, it can be advantageous if the stopper is slidably attached to the head unit by means of an actuator. This entails the advantage that the stopper can remain on the head unit of the outer shell when the melt receiving vessel is replaced. This results in the simplest possible structure and/or easy interchangeability of the melt receiving vessel.

Furthermore, it may be provided that the stopper has a heating element arranged in the stopper. This entails the advantage that, by this measure, the melt can mostly be prevented from freezing on the stopper.

In addition to this, it may be provided that the stopper has an outer wall, wherein an embedding powder in particular a magnesium oxide powder, is received inside the outer wall, wherein the heating element is embedded in the embedding powder. Such an embodiment entails the advantage that the heating element can be received in the stopper by these measures, wherein the high temperature fluctuations during the casting process do not lead to damage to the heating element.

An embodiment, according to which it can be provided that the heating element is coupled with current supply cables, wherein the current supply cables are freely guided between the head unit and the stopper in such a way that a relative movement of the stopper to the head unit is possible, is also advantageous. This entails the advantage that, by this measure, the electrical power required to operate the heating elements can be transported to the heating elements.

In an alternative embodiment variant, it may be provided that sliding contacts are formed between the head unit and the stopper for current transmission.

Furthermore, it may be provided that the current supply cable is sheathed with a heat-resistant electrical insulation, wherein the insulation is configured for maximum temperatures between 900° C. and 250° C.

A connecting element within the meaning of this document is advantageously a flange, but can also be formed as a conical shaped element. The sealing force required for the tightness of the lance on the melt receiving vessel is applied via the connecting element. In addition, the geometric position, such as the coaxiality and position of the outlet opening relative to the receptacle of the melt transport device, can be defined by the connecting element. This ensures easy replacement of the melt transport device.

For the purpose of better understanding of the invention, it will be elucidated in more detail by means of the figures below.

These show in a respectively very simplified schematic representation:

FIG. 1 a schematic representation of a first exemplary embodiment of a melt transport device;

FIG. 2 a sectional view of an exemplary embodiment of a stopper;

FIG. 3 a cross-sectional view of the stopper according to section line II-II of FIG. 2;

FIG. 4 a perspective view of a first exemplary embodiment of a base cover;

FIG. 5 a further exemplary embodiment of a connection of a lance to the melt receiving vessel;

FIG. 6 a further exemplary embodiment of a melt transport device with two lances;

FIG. 7 a further exemplary embodiment of a melt transport device with two lances; and two separate gas-tight chambers.

First of all, it is to be noted that in the different embodiments described, equal parts are provided with equal reference numbers and/or equal component designations, where the disclosures contained in the entire description may be analogously transferred to equal parts with equal reference numbers and/or equal component designations. Moreover, the specifications of location, such as at the top, at the bottom, at the side, chosen in the description refer to the directly described and depicted figure and in case of a change of position, these specifications of location are to be analogously transferred to the new position.

FIG. 1 shows a first exemplary embodiment of a melt transport device 1 which serves for transporting melt 2.

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

Moreover, the melt transport device 1 may comprise a spout 5 comprising, which is coupled to the melt container 3. The spout 5 may be designed as an integral component of the melt container 3. Moreover, it is also conceivable that the spout 5 is formed as a separate component which is coupled to the melt container 3. The spout 5 has a spout orifice 6, via which the melt 2 received in the melt container 3 can flow out of the melt transport device 1 into a mold.

Moreover, a gas valve 7 may be 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. The gas valve 7 is arranged above a fill level maximum 8, so that no melt 2 can flow into the gas valve 7. The fill level maximum is selected such that when the melt container 3 is filled to the fill level maximum 8 with melt 2, a gas-filled space still remains in the melt receiving space 4, in which gas-filled space a pressure can be set by means of the gas valve 7. Moreover, a pressure determining means 9 may be provided, by means of which an internal pressure in the melt receiving space 4 can be determined. Thus, the gas pressure in the melt receiving space 4 can be adjusted in a targeted manner by the gas valve 7.

Furthermore, a suction line 10 can be formed, 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 and/or be configured to allow gas to flow into the melt receiving space 4 in a targeted manner by means of the suction line 10.

As can also be seen from FIG. 1, it may be provided that the melt transport device 1 has a siphon 12.

The siphon 12 can be arranged between the melt receiving space 4 and the spout orifice 6.

As can also be seen from FIG. 1, it may be provided that the spout 5 is configured in the form of a lance 13. The siphon 12 may be arranged on the underside of the lance 13.

As can also be seen from FIG. 1, it may be provided that the melt container 3 has a gas-tight outer shell 14. A melt receiving vessel 15, which can serve to hold the melt 2, may be arranged inside the gas-tight outer shell 14. In particular, it may be provided that the melt receiving vessel 15 is configured in the form of a crucible, wherein the melt receiving space 4 is defined and/or limited by the melt receiving vessel 15. Further, it may be provided that the melt receiving vessel 15 comprises an outlet opening 16, which may be arranged in a lower region of the melt receiving vessel 15. In particular, it may be provided that the outlet opening 16 is formed as a central opening in the melt receiving vessel 15.

In particular, it may be provided that a vacuum can be created inside the outer shell 14 in order to allow the melt 2 to flow out of the melt receiving space 4 in a controlled manner and/or to be able to draw the melt 2 into the melt receiving space 4.

As can be seen particularly well from FIG. 1, it may be provided that the outlet opening 16 is formed in a base 17 of the melt receiving vessel 15. In this regard, the base 17 of the melt receiving vessel 15 can be conical so that the melt 2 is guided towards the outlet opening 16 when the melt level drops.

As can also be seen from FIG. 1, it may be provided that the melt receiving vessel 15 is configured to be open at the top. In an embodiment variant not shown, it may be provided that a splash guard is formed on an upper side of the melt receiving vessel 15.

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

Furthermore, it may be provided that a base flange 20 is formed which is welded to the jacket 18. In particular, it may be provided that the base flange 20 is configured for receiving a base cover 21. In particular, it may be provided that the base cover 21 is coupled to the base flange 20 by means of fastening means 22. Such fastening means 22 may be configured, for example, in the form of screws. In particular, it may be provided in this regard that a hole pattern in the form of through-holes 23, which are used for inserting the fastening means 22, is formed in both the base flange 20 and the base cover 21.

Furthermore, a central recess 24, which can serve as a passage for the melt 2, can be formed in the base cover 21. 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 accommodated in an indentation 26 of the central recess 24. The connecting element 25 can rest against a contact surface 27 of the melt receiving vessel 15.

Furthermore, it may be provided that a spring element 29 is arranged between the head unit 19 and an upper side 28 of the melt receiving vessel 15. In particular, it may be provided that multiple ones of the spring elements 29 are arranged distributed around the circumference between the head unit 19 and the melt receiving vessel 15. The spring elements 29 serve for pressing the melt receiving vessel 15 against the base cover 21.

As can also be seen from FIG. 1, it may be provided that a stopper 30 is formed, which can serve to close the outlet opening 16. In particular, it may be provided that the stopper 30 is configured to be displaceable relative to the melt receiving vessel 15 in a axial stopper direction 31. In this regard, the stopper 30 can be displaced in the axial stopper direction 31 by means of an actuator 32.

Furthermore, it may be provided that a heating element 33, which is configured to heat the stopper 30, is arranged in the stopper 30. In particular, it may be provided that the heating element 33 is coupled to a current supply cable 34, which is used to transmit the electrical energy for heating the heating element 33. The current supply cable 34 can be arranged on the head unit 19.

As can also be seen from FIG. 1, it may be provided that a vessel holder 47 is arranged on a bottom side of the outer shell 14. The vessel holder 47 can serve to receive and/or hold the melt receiving vessel 15 when the base cover 21 is removed from the outer shell 14 to replace the lance 13. In particular, it may be provided that the vessel holder 47 is formed parallel to the base cover 21.

FIG. 2 shows a sectional view of an exemplary embodiment of the stopper 30. FIG. 3 shows the associated cross-sectional view along the sectional line III-III from FIG. 2.

In the representation in FIGS. 2 and 3, the stopper 30 is shown in its closed position, so that it protrudes into the outlet opening 16.

As can be seen from FIG. 3, it may be provided that the stopper 30 has an outer wall 35, which may be hollow cylindrical. A rod-shaped heating element 33 can be received inside the outer wall 35. Furthermore, it may be provided that an embedding powder 36 is formed between the outer wall 35 and the rod-shaped heating element 33. The embedding powder 36 can serve to compensate for temperature-related thermal expansion between the outer wall 35 and the heating element 33.

As can be seen particularly clearly from FIG. 3, it may be provided that the stopper 30 has an outer diameter 37. The outlet opening 16 may have an inner diameter 38. In particular, it may be provided that the outer diameter 37 of the stopper 30 is smaller than the inner diameter 38 of the outlet opening 16. This allows an annular gap 39 to form between the stopper 30 and the inner wall of the outlet opening 16. The purpose of providing the annular gap 39 is to allow the stopper 30 to be inserted into the outlet opening 16 and/or to close it without touching the melt receiving vessel 15.

FIG. 4 shows a first exemplary embodiment of the base cover 21. As can be seen from FIG. 4, it may be provided that the base cover 21 has a depression 40 in the area of the central recess 24. The depression 40 can be configured in such a way that the connecting element 25 of the lance 13 can be received therein in a positive-locking manner. In particular, it may be provided that in the installed state of the base cover 21, the depression 40 is formed on an upper side and/or facing the melt receiving space 4.

Furthermore, it may be provided that tabs 41 are formed in which the through-holes 23 are arranged. The tabs 41 can protrude radially outwards.

As can also be seen from FIG. 4, it may be provided that a stepping 42 is formed which corresponds to the base flange 20. The stepping 42 allows the base cover 21 to be received being centered in the base flange 20. In particular, it may be provided that a first sealing groove 43 is formed in the area of the stepping 42. The first sealing groove 43 can be formed in an axial end face of the stepping 42 and serve to receive the axial seal.

Furthermore, it may be provided that a second sealing groove 44 is formed in the stepping 42. The second sealing groove 44 can be arranged in a circumferential surface of the stepping 42 and serve to receive a radial seal.

As can also be seen from FIG. 4, 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.

FIG. 5 shows a sectional view of a further exemplary embodiment of a detail for connecting the lance 13 to the melt receiving vessel 15, wherein, again, equal reference numbers and/or component designations are used for equal parts as before in FIGS. 1 to 4. In order to avoid unnecessary repetitions, it is pointed to/reference is made to the detailed description in FIGS. 1 through 4 preceding it.

As can be seen from FIG. 5, it may be provided that a fastening piece 48 of the melt receiving vessel 15 protrudes through the base cover 21. In this case, it may be provided that a step is formed in the melt receiving vessel 15, which step corresponds to the stepping 42 in the base cover 21. This step together with the stepping 42 can be used for axial positioning of the melt receiving vessel 15. Furthermore, an external thread, which serves to interact with a union nut 49, can be formed on the fastening piece 48. In this regard, the union nut 49 can be used to hold the lance 13 on the melt receiving vessel 15.

In particular, it may be provided that the union nut 49 has a retaining ring 50 which is positively engaged with the connecting element 25, whereby the connecting element 25 is pressed against the contact surface 27 by means of the union nut 49. In particular, it may be provided that a first seal 51 is arranged between the connecting element 25 and the contact surface 27. Furthermore, it may be provided that a second seal 52 is arranged between the retaining ring 50 of the union nut 49 and the connecting element 25 of the lance 13. Furthermore, it may be provided that a third seal 53 is arranged between the union nut 49 and the base cover 21.

In particular, it may be provided that sealing 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 base cover 21 when the union nut 49 is screwed on and/or when the lance 13 is in its fastened state. Thus, on the one hand, a melt-tight connection can be achieved between the lance 13 and the melt receiving vessel 15. On the other hand, a gas-tight connection of the outer shell 14 can be achieved by this measure. As a result, a vacuum can be generated in the melt receiving space 4.

FIG. 6 shows a further exemplary embodiment of the melt transport device 1, wherein, again, equal reference numbers and/or component designations are used for equal parts as before in FIGS. 1 to 5. In order to avoid unnecessary repetitions, it is pointed to/reference is made to the detailed description in FIGS. 1 through 5 preceding it.

As can be seen from FIG. 6, it can be provided that a first lance 13a and a second lance 13b are provided. Furthermore, it may be provided that a first melt receiving vessel 15a and a second melt receiving vessel 15b are provided. The two melt receiving vessels 15a and 15b can both be arranged inside the outer shell 14.

Furthermore, it may be provided that the lances 13a and 13b are each cranked and can be pivoted relative to the outer shell 14 about a vertical axis. In this regard, the vertical axis can be located in the center of the connection of the lances 13a and 13b to the melt receiving vessel 15a and 15b. This measure makes it possible to adjust the distance between the two spout orifices 6a and 6b of the two lances 13a and 13b relative to each other.

FIG. 7 shows a further exemplary embodiment of the melt transport device 1, wherein, again, equal reference numbers and/or component designations are used for equal parts as before in FIGS. 1 to 6. In order to avoid unnecessary repetitions, it is pointed to/reference is made to the detailed description in FIGS. 1 through 6 preceding it.

As can be seen from FIG. 7, it can be provided that the first lance 13a and the second lance 13b are provided. Furthermore, it may be provided that the first melt receiving vessel 15a and the second melt receiving vessel 15b are provided and the lances 13a and 13b are respectively assigned to the associated melt receiving vessel 15a and 15b. The two melt receiving vessels 15a and 15b can both be arranged inside the outer shell 14. As can also be seen from FIG. 7, it can be provided that the first melt receiving vessel 15a and the second melt receiving vessel 15b are each accommodated in a separate chamber. Thus, the first melt receiving vessel 15a and the second melt receiving vessel 15b can be subjected to a different vacuum in order to be able to control the casting process differently. In particular, different melts can be accommodated in the first melt receiving vessel 15a and the second melt receiving vessel 15b.

As can be seen from FIG. 7, it may be provided that the spout orifices 6a and 6b of the two lances 13a and 13b are arranged at a different height.

The exemplary embodiments show possible embodiment variants, and it should be noted in this respect that the invention is not restricted to these particular illustrated embodiment variants of it, but that rather also various combinations of the individual embodiment variants are possible and that this possibility of variation owing to the technical teaching provided by the present invention lies within the ability of the person skilled in the art in this technical field.

The scope of protection is determined by the claims. Nevertheless, the description and drawings are to be used for construing the claims. Individual features or feature combinations from the different exemplary embodiments shown and described may represent independent inventive solutions. The object underlying the independent inventive solutions may be gathered from the description.

All indications regarding ranges of values in the present description are to be understood such that these also comprise random and all partial ranges from it, for example, the indication 1 to 10 is to be understood such that it comprises all partial ranges based on the lower limit 1and the upper limit 10, i.e. all partial ranges start with a lower limit of 1 or larger and end with an upper limit of 10 or less, for example 1 through 1.7, or 3.2 through 8.1, or 5.5 through 10.

Finally, as a matter of form, it should be noted that for ease of understanding of the structure, elements are partially not depicted to scale and/or are enlarged and/or are reduced in size.